Dissertations / Theses: 'Periodontal Disease,Genetic evaluation'

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BALDINI, ALBERTO. "Valutazione della suscettibilità genetica alla malattia parodontale con analisi dei polimorfismi in una popolazione italiana." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/28145.

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Hennig, Branwen Johanna Wanda. "Genetic polymorphisms and early-onset periodontal diseases." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311107.

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Yiu, Kar-yung Cynthia. "Evaluation of interdental cleaning in adolescents and young adults in Hong Kong." Hong Kong : University of Hong Kong, 1989. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12556518.

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Loo, Tjing Yung, and 魯慶榮. "Profiles of cytokines and inflammatory mediators: implications in periodontal assessment." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45893305.

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Puglisi, Rosario. "Evaluation of instrumentation systems for periodontal mechanical treatment." Doctoral thesis, Universitat Internacional de Catalunya, 2017. http://hdl.handle.net/10803/461097.

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A major objective in the treatment of periodontitis is to reduce supra-gingival and sub-gingival plaque, dental calculus, and prevent recolonization of periodontal pockets by pathogenic bacteria{{117 Braun,A. 2005; 118 Dragoo,M.R. 1992; 119 Kocher,T. 2000; 120 Loos,B. 1987;}}. It is important for the clinician to achieve a controlled surface free of calculus and an optimal oral hygiene control by patients{{88 Keogh,T.P. 1993; 90 Alves,R.V. 2004; 89 Alves,R.V. 2005;}}. Previous studies have reported beneficial results from scaling and root planning in both clinical and microbiological aspects.{{139 Caffesse,R.G. 1986; 140 Huerzeler,M.B. 1998; 141 Leknes,K.N. 1994; 120 Loos,B. 1987; 143 Quirynen,M. 1990;}} The aim of this study is to provide new and relevant data on scaling and root planing methods in order to value the effectiveness (different changes in plaque index, probing pocket depth, attachment level, and bleeding on probing) and the morbidity of four different instrumentation systems (sensitivity and pain). The main objective is to analyze individually each instrument to analyze the effectiveness and the morbidity; the secondary objective is to compare the various instrumentation systems with the "gold standard" for scaling and root planing (Curettes + Ultrasound). Objectives: The results of this study will provide new relevant data on scaling and root planing methods. Main Objective: The main objective is to analyze the clinical effectiveness of 4 different instrumentation systems and compare the results, in terms of clinical attachment level gain, to non surgical periodontal therapy (periodontal debridement). Secondary Objectives: 1. To analyze the post-treatment morbidity for each method. 2. To analyze the working-time for each method. Focus of the Thesis to achieve the objectives: This in vivo study compared the effectiveness and morbidity of four different instruments using a split mouth design. Patients were chosen at the first visit to the department of Periodontology of the Dental Clinic of the Universitat Internacional de Catalunya UIC. On the first visit patients underwent a comprehensive periodontal examination. The operator carried out an initial examination of the patient and filled out a questionnaire relevant to the patient’s general information. A Periodontal examination was performed with a periodontal probe (HU-Friedy® - Chicago.IL.USA - COD: PCPUNC15 30 - CP15) and a periodontal chart used in the University Dental Clinic . The following parameters were examined: - plaque index (PI) {{171 O'Leary,T.J. 1972;}} - probing pocket depth (PPD) - probing attachment level (PAL) - bleeding on probing (BOP) {{170 Benamghar,L. 1982;}} - gingival recession (REC): measurement from the cementum-enamel junction to the gingival marginal crest - mobility (MOB) (Miller 1950) - furcation involvement (FI) (Hamp et al. 1975) - sensitivity (tested by the operator) After completion of initial screening, each patient (that met the selection criteria) was informed about his/her periodontal status and the clinical study. Each patient agreed to participate by signing a consent form. No patient was admitted to the study until the Informed Consent Form is signed. Twenty (20) patients were selected to obtain the statistical significance of the results and the analyses was performed using a statistical program (Stratigrafics for Windows). A power calculation before the initiation of this study revealed that a sample size of 17 patients was necessary to detect a difference of 1 mm for each clinical parameter, assuming a maximal mean - standard deviation of 1 mm. Inclusion criteria: - Patients with generalized moderate to severe chronic periodontitis - PPD : at least two sites with probing depth ≥4mm per multi-rooted teeth, and at least three sites with probing depth ≥4mm for all remaining teeth, per quadrant. (like in other studies) (44). - Systemically healthy patient Exclusion criteria - Patients who had had antibiotic therapy in the last 2 month or during the study - Patient less of 18 years old - Smokers - Pregnant woman - Remaining dentition of less than 20 teeth - Recent periodontal treatment - Allergies to local anesthetics - Physically handicapped subject and/or with mental disorders, who cannot assume proper plaque control - Aggressive periodontitis - Acute periodontal or endodontic infection - Systemic disease: - Cardiovascular disease: uncontrolled hypertension, stable and unstable angina, recent heart attack (<1 month), heart attack (> 1 month without symptoms), arrhythmias, heart failure. - Lung disease: chronic obstructive pulmonary disease, tuberculosis - Gastrointestinal disease: chronic active hepatitis, cirrhosis, pseudomembranous colitis, renal disease. - Genitourinary disease: chronic renal failure, sexually transmitted diseases (gonorrhea, syphilis, genital herpes, papillomavirus infection). - Endocrine and metabolic disease: diabetes mellitus, renal failure, hypothyroidism and hyperthyroidism, uncontrolled tiroiditis, thyroid cancer, pregnancy and lactation. - Immune disease: HIV infection and related conditions, connective tissue disorders (lupus erythematosus, pemphigus vulgaris, penfogoide, Sjogren's syndrome), organ transplant (heart, liver, kidney, pancreas, bone marrow). - Hematological disorders: Anemia, agranulocytosis, cyclic neutropenia, leukemia, multiple myeloma, lymphomas, thrombocytopenia, vascular wall, hemophilia, von Willebrand disease, disseminated intravascular coagulation, thrombocytopenia, primary fibrinogenolisis. - Oncological disease: patients undergoing radiotherapy and chemotherapy. - Psychiatric illness, disease of the behavior, neurological disease: epilepsy, Parkinson's syndrome, anxiety, eating disorders, delirium, schizophrenia, depression and bipolar disorder untreated. This in vivo study compared four different instruments using a split mouth design. The split mouth design selected for this study is the division of the mouth into 4 parts, each part corresponded to a quadrant. Four groups were formed (one for each instrument) and each quadrant (of each patient) was assigned to one clinically randomized group. The realization of treatment for each patient was made randomly using an informatical function of randomization. Groups Group A: curettes (Hu-Friedy®) Specific curettes were used following this plan: Gracey curettes 5/6 --- anterior teeth Gracey curettes 11/12 --- mesial surface of premolar and molar Gracey curettes 13/14 --- distal surface of premolar and molar Group B: conventional piezoelectric ultrasound (Suprasson P-5 Booster - Satelec®) was applied at a power between 11 and 12 with the insert n.1 (Satelec®). The minute vibration frequency of this ultrasound is 28-36 KHz. Group C: diamond burs 40 µm (Intensiv Perioset®) at 3,000 rpm. Group D: piezoelectric ultrasound - Piezosurgery 3 - Mectron® was applied in On/Mode Periodontics (ROOT) mode with the insert PP1 at a power between 2 and 3. The minute vibration frequency of this ultrasound is 24-36 KHz. One reevaluation visit was performed 1 week after the treatment of each quadrant and a questionnaire was used to analyze the post-treatment morbidity. During this visit only the hypersensibility of each tooth was tested with an air-stimulation by the operator. At 8 weeks a data collection was performed by an expert periodontist (A.S.) who was blinded to the study. All important parameters for this study were recorded (as we mentioned for the Periodontal examination). The pooled data at baseline and two months after instrumentation were then used for the statistical analysis. Each clinical parameter (plaque index, probing pocket depth, probing attachment level, bleeding on probing, gingival recession, mobility, furcation involvement and sensitivity) was analyzed for each group and for a comparison between the groups. The comparison of the four instrumentation systems find out the method that shows better results. Results At 8-week re-evaluation, regarding attachment level gain and probing pocket reduction, Gracey’s curettes, conventional ultrasound, and ultrasound Piezosurgery resulted statistical more effective when compared with diamond burs. Regarding to chair side time, a statistical difference was shown (p<0.001) when suprasson ultrasound and ultrasound Piezosurgery were compared with the others instruments. The post-treatment morbidity after scaling and root planning was not statistical difference for all the analysed instrumentations. The statistical difference was shown between baseline and weeks 1 and 4, and between weeks 1 and 8, and between weeks 4 and 8, when all the results were evaluated together. Better results at 8-week re-evaluation were obtained from the use of conventional ultrasonic device: 3.04 ± 2.39 (SD) but no statistical significance difference was shown (p>0.05) when compared with other groups. Conclusions Conventional Gracey curettes (Hu-Friedy®), conventional ultrasound (P-5 Booster Suprasson Satelec®) and ultrasound Piezosurgery Mectron® are more effective clinically when compared with diamond burs 40 µm (Intensiv Perioset®). The ultrasound instrumentation showed better results in terms of chair side time. Clinical Relevance The use of conventional curettes, conventional ultrasound and ultrasonic piezoelectric Mectron device prove to be more effective than 40 µm diamond burs in the non-surgical periodontal treatment.

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Lou, Xuemei. "Methods Evaluation and Application in Complex Human Genetic Disease." NCSU, 2008. http://www.lib.ncsu.edu/theses/available/etd-06122008-114358/.

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One of the most important tasks in human genetics is to search for disease susceptibility genes. Linkage and association analyses are two major approaches for disease-gene mapping. Chapter 1 reviewed the development of disease-gene mapping methods in the past decades. Gene mapping of complex human diseases often results in the identification of multiple potential risk variants within a gene and/or in the identification of multiple genes within a linkage peak. Thus a question of interest is to test whether the linkage result can be explained in part or in full by the candidate SNP if it shows evidence of association, and then provide some guidance for the next time-consuming step of positional cloning of susceptibility genes. Two methods, GIST and LAMP, which access whether the SNP can partially or fully account for the linkage signal in the region identified by a linkage scan, are evaluated on Genetic Analysis Workshop 15 (GAW15) simulated rheumatoid arthritis (RA) data and discussed in Chapter 2. The simulation results showed that GIST is simple and works slightly better than LAMP-LE test when there is little linkage evidence, LAMP linkage test has limited power when there is not much linkage evidence, and LAMP association test is the best not only when the linkage evidence is extremely high, but also when there is some LD between the candidate SNP and the trait locus. The fact that complex traits are often determined by multiple genetic and environmental factors with small-to-moderate effects makes it important to investigate the behavior of current association methods under multiple risk variants model. In Chapter 3, we compared APL, FBAT, LAMP, APL-Haplotype, FBAT-LC and APL-OSA conditional test in five multiple risk variants models. The simulation results showed that the power of single marker association tests is closely correlated with the amount of LD between marker and disease loci, and these tests maintain good power to detect multiple risk variants in a small region with moderate degree of LD for fully genotyped families. Global tests, such as FBAT-LC are sensitive to the presence of at least one susceptibility variant, but are not helpful for selecting the most promising SNPs for further study. We reported that if multiple haplotypes are associated with different disease loci, the haplotype tests results can be misleading while APL-OSA conditional test has the greatest power to properly dissect the clustered associated markers for all models with an acceptable type I error rate ranging from 0.033 to 0.056. We applied APL-OSA conditional test on GENECARD samples, and got reasonable results. One linkage region of particular interest on chromosome 3 was identified by two independent genome linkage scan with Coronary Artery Disease (CAD). Multiple disease susceptibility genes have been reported from this region, and there are also linkage evidence that this region may harbors a gene or genes determining HDL-C levels. Within this region, a search for HDL-C QTL and analyses of the relationship between genetic variants, HDL-C level to CAD risk are discussed in Chapter 4. We performed CAD association and HDL-C QTL analysis on two independent datasets. We identified SNP rs2979307 in the OSBPL11 gene which survives a Bonferroni correction. We observed different HDL-C trends with HDL-C associated SNPs. Even with the evident heterogeneity presented in our CAD population, we detected several association signals with SNPs in KALRN, MYLK, CDGAP and PAK2 genes in both CAD datasets for HDL-C, where all these genes belong to a Rho pathway.

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Yap, Benjamin C. M. "Rational design, synthesis and biological evaluation of porphyrin-antibiotic adducts targeting porphyromonas gingivalis." Thesis, The University of Sydney, 2009. https://hdl.handle.net/2123/28209.

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The aim of the project was to rationally design, synthesise and evaluate porphyrin-based growth inhibitors for the anaerobic bacterium Porphyromonas gingivalis, a key etiological agent implicated in destructive periodontitis. Periodontal diseases are caused by harmful bacteria that are present on the tooth’s surface and adjacent epithelium in the form of a biofilm. The biofilm is a complex microflora of bacteria and the Gram—negative anaerobes that predominate in the epithelial biofilm are of particular interest with respect to periodontal disease. A goal of this research was to resolve the missing link in Koch’s postulates establishing P. gingivalis as a key causative bacterium implicated in destructive periodontitis, which has still not been answered due to the lack of a drug that selectively eliminates it from the complex microflora in the biofilm. In the process of developing a therapeutic agent to inhibit the growth of P. gingivalis, the acquisition pathway for haem 1 was investigated. This is because P. gingivalis has an absolute requirement for exogeneous haem 1 as a growth factor. Optimal haem 1 uptake by P. gingivalis utilises characteristic surface proteins, the gingipains, for haemolysis, haemoglobin proteolysis and haem 1 capture. The highly conserved HA2 domain embedded in the haemagglutinin domain of the gingipains, is reported to act as a haemophore to capture and bind haem 1 which allows the utilisation of this feature for targeted inhibition. Previous work has established that the HA2 receptor recognises the porphyrin macrocycle with the particular requirement for a free propionic acid side-chain rather than recognition of the coordinated metal ion through chelation, a process used by other organisms with the HasA porphyrin receptor. Current treatment of periodontal disease involves the use of antibiotics as an adjunct to physical debridement. Metronidazole 2 is a potent nitroimidazole antibiotic with excellent activity against anaerobes. However, its broad spectrum of activity results in unwanted side effects. Consequently, work was set out to design and synthesise a porphyrin— antibiotic adduct that would act as a “Trojan horse” to improve the delivery of 2 into P. gingivalis. In this work, various porphyrin-antibiotic adducts were designed as potential highly selective P. gingivalis inhibitors, a key point being that they are based on the use of free-base porphyrins to render them unpalatable to other organisms. In the process, a porphyrin— antibiotic adduct 25a and 25b in which metronidazole 2 was directly attached to DPIX 6 by an ester linkage was found to show much higher selectivity for P. gingivalis than to other bacteria. A porphyrin—antibiotic adduct 31/32 in which the amine derivative of metronidazole 33 was directly attached to 6 by an amide linkage was found to be two—fold more active than 2 in inhibiting growth of P. gingivalis and twenty-fold more potent than 37 indicating that adduct 31/32 acts as a single entity at the cell’s surface. The methyl ester version of this adduct 37/38, in contrast, is not recognised by HA2 and is ineffective in inhibiting P. gingivalis, leading to the conclusion that capture by HA2 may be necessary for activity of the adducts. The mixture of the two regioisomers of the amide linked mono—metronidazole adducts 31 and 32 were resolved by HPLC and were shown to have similar activities to each other and to the mixture itself, suggesting that separation of the isomers is not crucial. Adduct 40a and 40b whereby 33 was attached to DPIX 6 through a lysine was found to be as potent as 2. However, efforts to improve its water solubility and potency by modifying the lysine side—chain proved unsuccessful. This suggests limitations with respect to the amount of modifications that can be carried out on the porphyrin—antibiotic adducts. Through this, new insights were provided into the initially proposed HA2 binding site and a refinement of the binding site was established to aid the design of future drugs. An active lysine—linked porphyrin-antibiotic adduct 70a and 70b linked to a peptide-biotin compound through the lysine side-chain was synthesised and was shown to be specifically cleaved by the lysine—specific gingipains. When biotin 60 is replaced with an antibody to give the adduct 67a and 67b, the adduct 67a and 67b has the potential to localise at the surface of the diseased epithelium and provides the opportunity to create a depot of adducts localised at the disease site and offer a targeted delivery approach. Synthetic efforts using Se-S chemistry to link pophyrin—antibiotic adducts to proteins such as antibodies specific to an antigen expressed on the surface of diseased epithelium are also discussed.

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Lu, Qian. "Expression and regulation of human [beta]-defensins in gingival epithelia." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36613708.

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Pinheiro, Regina Márcia Serpa. "Evaluation of microbial and salivary parameters in disease periodontal associated with diagnosis of type II diabetes mellitus." Universidade de Taubaté, 2010. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=435.

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The present cross-sectional study aimed to validate different biological factors relate to periodontal and diabetes diseases. Objective: Our study compared microbiological and salivary parameters of diabetics and non diabetics subjects matched by periodontal profile. Method: A total of 29 diabetic and 32 non diabetic subjects were included in this survey. The study population, allocated in Porto Velho-RO, Brazil, was submitted to clinical periodontal examinations, such as: Periodontal pocket depth (PPD), Clinical attachment loss (CAL), Plaque index (PI) and Gingival index (GI) as well as salivary, fasting blood glucose and glycated hemoglobin tests. Additionally, the presence of Agregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forshythia and Campylobacter rectus was performed by Polimerase Chain Reaction. Results: We observed the following clinical results: at the TG, mean values of PPD, CAL, PI and GI were respectively (2.410.64); (2.761.66); (0.460.24; (0.280.15) while at the CG were (2.550.71); (2.381.72); (0.400.24); (0.340.20). According to microbiological data we observed that the most prevalent pathogens in both groups were P. gingivalis (TG: 86.2%; CG:90,6%) and T. forsythia (TG: 93,1%; CG: 96,8%). Took in consideration parameters such as: Weight, body mass index and saliva we also verified no statistically significant differences between groups, on the other hand, the mean rates of glucose in diabetic patients were higher (p<0.05) than non diabetic subjects. Conclusion: The results of this study showed that salivary and microbial factors did not differ between groups, so these factors were not represent an important tool to characterize differences between diabetic and non diabetic patients. Then, we also recommend a different approaches, such as, longitudinal studies to validate these biological factors in the relationship of periodontal disease and diabetes.
A fundamentação do presente estudo foi o de validar alguns fatores biológicos importantes na associação doença periodontal e diabetes em estudo do tipo transversal. Objetivo: Foi comparar o perfil microbiano e salivar de indivíduos diabéticos (GT) em relação a não diabéticos (GC) equilibrados sob características clínicas periodontais Método: Foram incluídos 29 indivíduos diabéticos e 32 não-diabéticos, de ambos os gêneros, alocados em Porto Velho/RO e submetidos a exames laboratoriais como glicemia de jejum e hemoglobina glicada. Foi realizada ainda avaliação clínica bucal incluindo mensurações de profundidade de bolsa (PS), perda de inserção clínica (PIC), índice de placa (IP) e gengival (IG) para estabelecimento do diagnóstico periodontal. Exames microbianos foram realizados para avaliar a presença de Agregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevoltella intermedia, Tannerella forshythia, e Campylobacter rectus por Reação em cadeia da polimerase (PCR). Os exames salivares avaliaram pH, fluxo salivar, capacidade tampão e concentração de glicose na saliva. Resultados: Os valores médios e desvio-padrão dos parâmetros clínicos de PS, PIC, IP e IG foram respectivamente: GT (2,410,64); (2,761,66); (0,460,24; (0,280,15) e GC (2,550,71); (2,381,72); (0,400,24); (0,340,20). Na análise microbiológica, os patógenos mais prevalentes em ambos os grupos foram P. gingivalis e T. forsythia (GT: 86,2%; GC: 90,6%) e (GT: 93,1%; GC: 96,8%). Peso, Indice de massa corporal (IMC) e análise salivar, apresentaram-se iguais em ambos os grupos. As taxas glicêmicas dos indivíduos diabéticos foram superiores (p<0,05) as dos indivíduos não diabéticos. Conclusão: Após avaliação dos resultados concluímos que os fatores microbianos e salivares não diferiram entre os grupos examinados, logo estes fatores não foram importantes na caracterização de diabéticos e não diabéticos neste modelo de estudo. A condução de estudos longitudinais poderá elucidar a validade destes fatores biológicos na relação doença periodontal e diabetes.

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Barbosa, Marcela Di Moura 1989. "Índices CPI e PSR na avaliação da doença periodontal em adultos e idosos = CPI and PSR index on evaluation of periodontal disease in adults and seniors." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289494.

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Orientadores: Karina Gonzales Silvério Ruiz, Cristiane Ribeiro Salmon
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-27T14:21:58Z (GMT). No. of bitstreams: 1 Barbosa_MarcelaDiMoura_M.pdf: 3074144 bytes, checksum: 106aa08cced6cc330bfb74a1eeb1a037 (MD5) Previous issue date: 2015
Resumo: As doenças periodontais são doenças inflamatórias crônicas que afetam os tecidos periodontais de suporte do dente podendo ser destrutivas ou não. A identificação dessas doenças em estudos epidemiológicos é feita com o uso de índices periodontais que visam simplificar a coleta dos dados e possibilitar a identificação da doença em grandes populações. O presente estudo teve como objetivos avaliar as condições de saúde bucal da população do Município de Jundiaí, SP, determinando a prevalência das condições periodontais em indivíduos adultos e idosos comparando o Índice Periodontal Comunitário (CPI) e o Periodontal Screening and Recording (PSR), descrever o perfil demográfico, socioeconômico, o acesso a serviços odontológicos e os hábitos de higiene bucal e verificar a associação entre condições socioeconômicas, demográficas, hábitos de higiene bucal, utilização de serviço odontológico e tabagismo com a doença periodontal. Este estudo transversal foi realizado no Município de Jundiaí, Estado de São Paulo, entre o período de abril a setembro/2014. Foram estudados 372 indivíduos adultos (35 a 44 anos de idade) e 162 idosos (65 a 74 anos de idade) residentes no Município de Jundiaí e visitados em suas residências. Participaram da coleta de dados 5 Cirurgiões-Dentistas que passaram por calibração, apresentando concordância para os índices CPI e PSR de 63 a 91%, com Kappa variando de 0,63 a 0,76. Para as características demográficas e socioeconômicas, hábitos de higiene bucal, informações sobre saúde bucal, utilização de serviço odontológico e condições periodontais, foi realizada a análise descritiva dos dados para a população adulta e idosa, apresentada como valores absolutos (n) e prevalência (%). A diferença entre a média de sextantes afetados com cada condição periodontal para os índices CPI e PSR foi avaliada pelo teste T pareado. Verificou-se que 68% dos adultos e 60,5% dos idosos examinados eram do sexo feminino, 46% e 37% têm renda familiar de 4 salários mínimos ou mais, respectivamente. 57,3% dos adultos e 64,2% dos idosos afirmaram desconhecer o que é a doença periodontal. 58,6% dos adultos com profundidade de bolsa ?4mm afirmaram ter vivido uma infância pobre ou muito pobre e 73,9% afirmaram que a situação econômica atual estava melhor que a da infância. Comparando-se os índices CPI e PSR, houve diferença estatística significativa para o diagnóstico de sextantes saudáveis, presença de bolsa rasa (código 3, bolsa periodontais de 4mm a 5mm) e bolsa profunda (código 4, bolsas com profundidade de sondagem ?6mm), sendo que o índice CPI subestimou a periodontite e superestimou os sextantes saudáveis quando comparado aos resultados de PSR. Escolaridade, situação econômica na infância, frequência de visita ao dentista, uso de fio dental e tabagismo, estiveram associados a maior prevalência de doença periodontal na população adulta. Por outro lado, somente o intervalo de tempo desde a última consulta odontológica e o fato do indivíduo ser ex-fumante estiveram associados a maior prevalência de doença periodontal nos indivíduos idosos
Abstract: Periodontal diseases are chronic inflammatory diseases that affect the periodontal tissues of tooth support and can be destructive or not. The identification of these diseases in epidemiological studies is made with the use of periodontal index to simplify data collection and enable the identification of disease in large populations. This study aimed to evaluate the oral health status of the population of the city of Jundiaí, SP. Determinate the prevalence of periodontal conditions in adults and elderly subjects by comparing the Community Periodontal Index (CPI) and the Periodontal Screening and Recording (PSR). Describe the demographic and socioeconomic profile, access to dental services and oral hygiene habits. Determinate the association between socioeconomic and demographic conditions, oral hygiene, dental service use and smoking habits with periodontal disease. This cross-sectional study was conducted in the city of Jundiaí, São Paulo, between the period April to September / 2014. 372 adults (35-44 years old) were studied and 162 elderly (65-74 years old) residing in the city of Jundiaí and visited in their homes. Participated in data collection 5 dentists who pass through calibration, with agreement for the CPI and PSR rates 63-91%, with kappa ranging from 0.63 to 0.76. For demographic and socioeconomic characteristics, oral hygiene habits, information on oral health, dental service utilization and periodontal conditions, the descriptive analysis of data was performed for adult and elderly population, presented as absolute (n) and prevalence (%). It was found that 68% of adults and 60.5% of elderly participants were female, 46% and 37% have household income of R$3000,00 or more, respectively. 57.3% of adults and 64.2% of the elderly said unaware of what is periodontal disease. 58.6% of adults with pocket probing depth ?4mm said they lived a poor or very poor children and 73.9% said that the current economic situation was better than that of childhood. Comparing the CPI and PSR levels, there was statistically significant difference for the diagnosis of healthy sextants, presence of shallow pocket (code 3, periodontal pocket 4mm to 5mm) and deep pocket (code 4, probing depth ?6mm), where CPI index underestimated periodontitis and overestimated healthy sextants when compared to the PSR results. Education, economic status in childhood, frequency of dental visits, use of dental wire and smoking were associated with a higher prevalence of periodontal disease in the adult population. On the other hand, only the time interval since the last dental visit and the fact that the former smokers were associated with higher prevalence of periodontal disease in the elderly
Mestrado
Periodontia
Mestra em Clínica Odontológica

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Boyd, Marie. "Evaluation of screening strategies for the detection of molecular pathologies." Thesis, University of Glasgow, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295318.

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Yiu, Kar-yung Cynthia, and 姚嘉榕. "Evaluation of interdental cleaning in adolescents and young adults in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1989. http://hub.hku.hk/bib/B31953918.

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Lu, Qian, and 陸茜. "Expression and regulation of human {221}-defensins in gingival epithelia." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B36613708.

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Oliveira, Luciano Santos. "Prevalência do polimorfismo -1031 T>C do gene TNFA em um grupo de diabéticos tipo I e sua relação com a periodontite severa." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=6756.

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Pontifícia Universidade Católica do Rio de Janeiro
Diabetes mellitus e doenças periodontais são altamente prevalentes na população mundial. Doenças periodontais (DPs) compreendem um grupo de condições crônicas inflamatórias induzidas por microorganismos que levam à inflamação gengival, à destruição tecidual periodontal e à perda óssea alveolar. Diabetes mellitus (DM) é o termo utilizado para descrever um grupo de desordens metabólicas associadas à intolerância à glicose e ao metabolismo inadequado de carboidratos. Uma vez que DPs poderiam agir de forma similar a outros estados infecciosos sistêmicos, aumentando a severidade do diabetes, uma possível relação entre ambas tem sido considerada em todo o mundo. Polimorfismos genéticos de um único nucleotídeo (SNPs) têm sido estudados em diversas doenças. Nas periodontites, acredita-se que possam estar envolvidos na exacerbação da resposta inflamatória frente ao desafio bacteriano, modificando a susceptibilidade do hospedeiro. Neste estudo, a prevalência de periodontite foi avaliada em portadores de diabetes mellitus tipo I. Posteriormente, o SNP localizado na região promotora do gene TNFA (-1031T>C) foi analisado e sua importância para a doença periodontal destrutiva foi avaliada. O grupo teste foi constituído por diabéticos tipo I (DGT, n=113) enquanto o grupo controle por indivíduos não diabéticos (ND, n=73). Para as análises dos polimorfismos genéticos, um subgrupo foi retirado do grupo teste (DG, n=58) e comparado ao grupo ND. Os seguintes parâmetros clínicos e demográficos foram avaliados: percentual de sítios com profundidade de bolsa  6,0 mm (%PBS6,0 mm); índice gengival (IG); perda óssea radiográfica (POR); fumo; duração do diabetes ; idade; índice de massa corpórea (IMC), n de internações e n de dentes presentes. Amostras de sangue e/ou esfregaço bucal foram colhidas de 58 pacientes do grupo teste e de 73 controles. Após a extração do DNA genômico e amplificação da região genômica de interesse por PCR (Polymerase Chain Reaction), o polimorfismo TNFA 1031T>C foi analisado por BbsI RFLP (Restriction Fragment Length Polymorphism). A análise dos produtos de digestão foi feita por eletroforese em gel de poliacrilamida 8%. A análise estatística das freqüências alélica e genotípica juntamente com os dados clínicos e epidemiológicos entre os 2 grupos foi feita através do teste do Mann-Whitney e do Qui-quadrado. Os grupos de estudo obedecem ao princípio de Hardy-Weinberg. No grupo ND, as seguintes freqüências genotípicas foram encontradas: 78,1% (T/T); 20,5% (T/C) e 1,4% (C/C) enquanto no grupo D foram: 42,4%(T/T); 37,3% (T/C) e 20,3% (C/C). A frequência do alelo T no grupo diabético (D) foi de 0,610 ao passo que no grupo ND foi de 0,883. Não foi possível encontrar uma relação entre o polimorfismo -1031 T>C do gene TNFA e a presença de periodontite em diabéticos tipo I. Entretanto, o polimorfismo estudado se mostrou significativamente relacionado (p<0,0001 e OR= 4.85 95%IC 2,271-10,338) à presença do diabetes tipo I.
Diabetes mellitus and periodontal diseases are highly prevalent worldwide. Periodontal disease (PD) combines a group of chronic inflammatory conditions induced by microorganisms that leads to gingival inflammation, periodontal tissue destruction and alveolar bone loss. Diabetes mellitus (DM) is a term used to describe a group of metabolic disorders associated to glucose intolerance and inappropriate carbohydrate metabolism. Once PDs could act in a similar way to other systemic infectious states increasing diabetes severity, a possible correlation between both has been considerate around the world. Single nucleotide polymorphisms (SNPs) have been studied in relation to several diseases. In periodontitis, it is believed to be involved in an exacerbated inflammatory response due to bacterial challenge, modifying the host susceptibility. In this study, the prevalence of periodontal disease was evaluated in type I diabetes patients (TIDM). Further on, the SNP in the promoter region of the TNFA gene (-1031T>C) was analyzed and its importance to destructive periodontal disease was considered. The test group was formed by type I diabetic patients (TDG, n=113) and the control group was composed by non-diabetic patients (ND, n=73). For the genetic polymorphism analysis a subgroup was taken from the test group (DG, n=58) and compared to the ND group. The following clinical and demographic parameters were assessed: percentage of sites with periodontal pocket depth (PPD)  6.0mm; gingival index (GI); radiographic bone loss (RBL); smoking habits; diabetes duration; age; bone mass index (BMI); number of admissions and number of teeth. Blood samples and oral epithelial cells were collected from 58 patients of the test group and 73 controls. After genomic DNA extraction and amplification of the genomic region of interest by PCR (Polymerase Chain Reaction), the TNFA 1031T>C polymorphism was analyzed by BbsI RFLP (Restriction Fragment Length Polymorphism). Analysis of the digestion products were performed by 8% polyacrylamide gel electrophoresis. The statistical analysis of the genotypes and allelic frequencies along with the clinical and epidemiological data between the two groups were done through the Mann-Whitney and Chi-square tests. The study groups are in Hardy-Weinberg equilibrium. In the ND group, the following genotypic frequencies were found: 78.1% (T/T); 20.5% (T/C) e 1.4% (C/C), while for the D group, they were: 42.4% (T/T); 37.3% (T/C) e 20.3% (C/C). The frequencies of T allele in the D and ND groups were 0.610 and 0.883, respectively. It was not possible to find any correlation between the -1031 T>C promoter polymorphism of the TNFA gene and the presence of periodontitis in type I diabetic patients. However the studied polymorphism showed to be significantly related (p<0.0001 and OR=4.85 95%CI 2.271-10.338) to the presence of type I diabetes mellitus.

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15

Schneider, Matthew John. "An evaluation of the genetic components of bovine respiratory disease and its influence on production traits." [Ames, Iowa : Iowa State University], 2008.

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16

Namukwaya, Betty. "Evaluation of transgenic bananas expressing anti-apoptotic genes for resistance against Fusarium wilt." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/91393/1/Betty_Namukwaya_Thesis.pdf.

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The banana industry worldwide is under threat from a fungal disease known as Fusarium wilt, a disease for which there is no chemical control. Conventional breeding approaches to generate resistant banana varieties are lengthy and very difficult. As such, genetic engineering for disease resistance is considered the most viable control option. In this PhD thesis, genetically modified banana plants were generated using several different stress tolerance genes. When challenged with Fusarium wilt in glasshouse trials, some lines showed increased resistance to the disease. The promising elite lines generated in this study will now require testing in field trials.

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17

Spaner, Dean Michael. "Agronomic evaluation of short season quality protein maize." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61042.

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The introduction of Quality Protein Maize (QPM), hard endosperm opaque-2 maize, into northern temperate maize growing areas is a desirable breeding objective. In topcrosses with opaque-2 testers, in diallel combination, as inbreds per se, and in inbred disease screening nurseries, some QPM lines performed better than or equal to the best local checks. In general, while agronomic potential is high for some lines and gains from selection are statistically possible, longer days to flowering intervals and higher levels of moisture at harvest than check hybrids indicated a need to improve adaptation for the locations studied. Methodology experiments indicated that detasselling of check hybrids is a suitable experimental method to facilitate the inclusion of normal endosperm local checks into QPM performance tests. The screening for Fusarium graminearum resistance in the seedling stage has not been proven to be a viable alternative to field scale ear inoculation screening procedures. (Abstract shortened by UMI.)

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18

Corbi, Sâmia Cruz Tfaile. "Avaliação clínica, imunológica e da resposta ao tratamento periodontal não-cirúrgico em indivíduos com e sem haplótipos de suscetibilidade genética à periodontite crônica no gene interleucina 8 /." Araraquara : [s.n.], 2010. http://hdl.handle.net/11449/95385.

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Orientador: Raquel Mantuaneli Scarel Caminaga
Banca: Silvana Regina Perez Orrico
Banca: Andréa Márcia Marcaccini
Resumo: A Doença Periodontal (DP) tem caráter multifatorial, com a influência de fatores como a presença de microrganismos periodontopatogênicos, suscetibilidade genética do hospedeiro, reação do sistema imune, hábito de fumar e presença de doenças sistêmicas. O tecido periodontal inflamado produz várias citocinas, dentre elas a interleucina 8 (IL-8). Estudos recentes realizados por este grupo investigaram polimorfismos no gene IL8 em indivíduos com e sem periodontite crônica, onde foram observados indivíduos com 2 vezes mais predisposição genética à DP. O objetivo do presente estudo foi testar a hipótese de que a maior suscetibilidade genética à periodontite crônica dada pelo haplótipo ATC/TTC no gene IL8 seria acompanhada por diferenças nos índices clínicos periodontais, nos níveis da citocina IL-8 no fluido sulcular (FS) e na resposta ao tratamento periodontal não-cirúrgico. Foram selecionados 79 indivíduos divididos quanto à presença ou não do referido haplótipo no gene IL8, de forma que os indivíduos "suscetíveis" e "não suscetíveis" foram subdivididos quanto à presença ou ausência da periodontite crônica. Os indivíduos selecionados foram submetidos a exame clínico periodontal e coletas de FS antes e após 45 dias de finalizado o tratamento periodontal não-cirúrgico. A citocina IL-8 foi quantificada por meio de teste imunoenzimático (ELISA). Como resultado verificou-se que, comparando indivíduos suscetíveis e não-suscetíveis à DP, não houve diferença estatisticamente significante tanto nos índices clínicos periodontais quanto na resposta ao tratamento periodontal realizado, sendo que apenas o volume do FS, no período baseline, apresentou diferença significativa. Assim, a suscetibilidade genética à DP previamente observada nesses indivíduos não... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Periodontal disease is a multifactorial disease which is influenced by factors such as the presence of periodontopathogenic microorganisms, the reaction of the immune system, smoking, genetic susceptibility and the occurrence of systemic diseases. The inflamed periodontal tissue produces several cytokines like Interleukin 8 (IL-8). Recent studies carried out by our research group investigated polymorphisms in the IL8 gene in patients with and without periodontitis, where it was found individuals with a genetic predisposition to periodontitis. The purpose of this study was to test the hypothesis that the genetic susceptibility to chronic periodontitis given by ATC/TTC haplotype in IL8 gene would be linked to differences in the clinical periodontal parameters, IL-8 cytokine levels in the gingival crevicular fluid (GCF) and the response to non-surgical periodontal therapy. Seventy-nine individuals were selected and grouped according to the presence or not of the haplotype given in the IL8 gene, so that the "susceptible" and "nonsusceptible" individuals were subdivided by the presence or absence of chronic periodontitis. The selected individuals were submitted to periodontal clinical exam and the collection of GCF was done before and 45 days after the non-surgical periodontal therapy. The IL-8 cytokine was quantified through an immunoenzymatic assay (ELISA). As a result, it was verified that, comparing susceptible and non-susceptible individuals to chronic periodontitis, there wasn't any statistically significant difference as in clinical periodontal parameters as in response to non-surgical periodontal therapy. However, the volume of GCF, at baseline, presented a significant difference. Thus, the genetic susceptibility to chronic periodontitis previously observed in these individuals influenced neither... (Complete abstract, click electronic access below)
Mestre

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19

Lau, Ko-chun Danny, and 劉高駿. "Evaluation of thyroid transcription factor-1 (TTF1) and homeobox B5 (HOXB5) as Hirschsprung disease (HSCR) susceptibility loci." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B38679851.

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20

Futter, Merle. "Predictive testing and clinical genetic counselling services for Huntington disease in the Western Cape : an evaluation over eleven years." Doctoral thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/3094.

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Corbi, Sâmia Cruz Tfaile [UNESP]. "Avaliação clínica, imunológica e da resposta ao tratamento periodontal não-cirúrgico em indivíduos com e sem haplótipos de suscetibilidade genética à periodontite crônica no gene interleucina 8." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/95385.

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Made available in DSpace on 2014-06-11T19:27:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-25Bitstream added on 2014-06-13T19:56:29Z : No. of bitstreams: 1 corbi_sct_me_arafo.pdf: 500522 bytes, checksum: acbb0ada52f0fc0619726c5c3c57e5c5 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A Doença Periodontal (DP) tem caráter multifatorial, com a influência de fatores como a presença de microrganismos periodontopatogênicos, suscetibilidade genética do hospedeiro, reação do sistema imune, hábito de fumar e presença de doenças sistêmicas. O tecido periodontal inflamado produz várias citocinas, dentre elas a interleucina 8 (IL-8). Estudos recentes realizados por este grupo investigaram polimorfismos no gene IL8 em indivíduos com e sem periodontite crônica, onde foram observados indivíduos com 2 vezes mais predisposição genética à DP. O objetivo do presente estudo foi testar a hipótese de que a maior suscetibilidade genética à periodontite crônica dada pelo haplótipo ATC/TTC no gene IL8 seria acompanhada por diferenças nos índices clínicos periodontais, nos níveis da citocina IL-8 no fluido sulcular (FS) e na resposta ao tratamento periodontal não-cirúrgico. Foram selecionados 79 indivíduos divididos quanto à presença ou não do referido haplótipo no gene IL8, de forma que os indivíduos “suscetíveis” e “não suscetíveis” foram subdivididos quanto à presença ou ausência da periodontite crônica. Os indivíduos selecionados foram submetidos a exame clínico periodontal e coletas de FS antes e após 45 dias de finalizado o tratamento periodontal não-cirúrgico. A citocina IL-8 foi quantificada por meio de teste imunoenzimático (ELISA). Como resultado verificou-se que, comparando indivíduos suscetíveis e não-suscetíveis à DP, não houve diferença estatisticamente significante tanto nos índices clínicos periodontais quanto na resposta ao tratamento periodontal realizado, sendo que apenas o volume do FS, no período baseline, apresentou diferença significativa. Assim, a suscetibilidade genética à DP previamente observada nesses indivíduos não...
Periodontal disease is a multifactorial disease which is influenced by factors such as the presence of periodontopathogenic microorganisms, the reaction of the immune system, smoking, genetic susceptibility and the occurrence of systemic diseases. The inflamed periodontal tissue produces several cytokines like Interleukin 8 (IL-8). Recent studies carried out by our research group investigated polymorphisms in the IL8 gene in patients with and without periodontitis, where it was found individuals with a genetic predisposition to periodontitis. The purpose of this study was to test the hypothesis that the genetic susceptibility to chronic periodontitis given by ATC/TTC haplotype in IL8 gene would be linked to differences in the clinical periodontal parameters, IL-8 cytokine levels in the gingival crevicular fluid (GCF) and the response to non-surgical periodontal therapy. Seventy-nine individuals were selected and grouped according to the presence or not of the haplotype given in the IL8 gene, so that the “susceptible” and “nonsusceptible” individuals were subdivided by the presence or absence of chronic periodontitis. The selected individuals were submitted to periodontal clinical exam and the collection of GCF was done before and 45 days after the non-surgical periodontal therapy. The IL-8 cytokine was quantified through an immunoenzymatic assay (ELISA). As a result, it was verified that, comparing susceptible and non-susceptible individuals to chronic periodontitis, there wasn’t any statistically significant difference as in clinical periodontal parameters as in response to non-surgical periodontal therapy. However, the volume of GCF, at baseline, presented a significant difference. Thus, the genetic susceptibility to chronic periodontitis previously observed in these individuals influenced neither... (Complete abstract, click electronic access below)

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22

Fisher, Leslie Reginald. "Evaluation of high-throughput methodology for multi-gene screening in patients with Non-Alcoholic Fatty Liver Disease (NAFLD)." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17896.

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Thesis (MScMedSc)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: Non-Alcoholic Fatty Liver Disease (NAFLD) is the most prevalent chronic liver disease in Western countries and is considered the hepatic manifestation of the Metabolic Syndrome (MetS). Its heterogeneous nature ranges from hepatic steatosis through steatohepatitis to advanced fibrosis and cirrhosis where the ingestion of significant amounts of alcohol has been excluded. The disease profile of NAFLD and its necro-inflammatory subset Nonalcoholic Steatohepatitis (NASH) were described in the parent study, which provided a clinically well-characterised patient cohort for the present investigation. South African patients with NASH had significantly higher mean serum cholesterol and triglyceride levels than those with fatty liver only. The objective of this study was to implement a high-throughput real-time polymerase chain reaction (PCR) method in our laboratory to enable the assessment of cardiovascular genetic risk factors in NAFLD patients. The specific aims were to determine the clinical utility and perform analytical validation of each mutation included in the multi-gene cardiovascular disease (CVD) screening assay. The Pathology Supported Genetic Testing (PSGT) concept developed at our department provides a practical approach to personalized medicine. The CVD multi-gene screen analyses key metabolic pathways relating to atherogenic dyslipidaemia, chronic inflammation, hypercoagulation and iron dysregulation implicated in insulin resistance, which is known to be a universal factor in the pathogenesis of NAFLD. Deleterious low-penetrance mutations in the APOE (APOE2 and E4 alleles), MTHFR (677C>T and 1298A>C), F2 (20210G>A), FV (1691G>A, Leiden) and HFE (C282Y and H63D) genes were included for analysis due to their important role as genetic contributors to these biological processes. A total of 178 patients diagnosed with NAFLD and 75 controls were studied using direct DNA sequencing and a RT-PCR system for mutation detection. In addition, two patients with high ferritin levels were included as case studies. A significant association was found between HFE mutations and elevated Alanine Transaminase (ALT) levels in the NAFLD population (p = 0.04). This discovery is interpreted as the identification of a subset of patients at greater risk of developing progressive liver damage who would benefit most from genetic testing to direct more aggressive therapy at an earlier stage. The necessity of an integrative, systems-based network approach was demonstrated to more accurately distinguish between Hereditary Haemochromatosis (HH) and Insulin Resistance-associated Hepatic Iron Overload (IR-HIO) syndrome in obese patients. The PSGT approach to personalized medicine facilitates diagnosis of CVD subtypes, prevention of cumulative risk and the formulation of gene-based intervention programs tailored to the needs of the patient. These findings support the clinical utility of the CVD multi-gene test to guide chronic disease risk management in patients with NAFLD. The HFE mutation detection component of this test is of particular relevance in directing an effective treatment strategy in patients with a medical history of CVD and/or high iron stores.
AFRIKAANSE OPSOMMING: Nie-Alkoholiese Vettige Lewer Siekte (NAFLD) is die mees algemene kroniese lewer siekte in Westerse lande en word bestempel as die hepatiese manifestasie van die Metaboliese Sindroom (MetS). Die heterogene natuur van NAFLD strek van hepatiese steatose deur steatohepatietis tot gevorderde fibrose en sirrose waar grootskaalse alkohol inname uitgesluit is. Die siekte-profiel van NAFLD en sy nekro-inflammatoriese subtipe Nie-Alkoholiese Steatohepatietis (NASH) is reeds beskryf in die ouer studie, wat ‗n klinies goed-gekarakteriseerde pasiënt groep vir die huidige ondersoek daar gestel het. Suid-Afrikaanse pasiënte met NASH het beduidend hoër gemiddelde serum cholesterol en trigliseried vlakke in vergelyking met slegs vettige lewer. Die doel van hierdie studie was om ‗n hoë deurvoer rieëltyd polimerase kettingreaksie (RT-PCR) metode in ons laboratorium te implimenteer om kardiovaskulêre genetiese risiko faktore in NAFLD pasiënte te ondersoek. Die spesifieke mikpunte was om die kliniese nut en analitiese geldigheid van elke mutasie wat ingesluit is in die multi-geen kardiovaskulêre siekte (KVS) siftings toets vas te stel. Die Patologie Ondersteunde Genetiese Toetsing (PSGT) konsep wat by ons departement ontwikkel is, verskaf ‗n praktiese benadering tot persoonlike medisyne. Die KVS multi-geen toets analiseer belangrike metaboliese weë verwant aan atherogene dyslipidemie, kroniese inflammasie, oormatige bloedstolling en yster disregulering wat betrokke is by insulien weerstand wat bekend is as ‗n universele factor in the patogenese van NAFLD. Nadelige lae-penetrasie mutasies in die APOE (APOE2 en E4 allele), MTHFR (677C>T en 1298A>C) F2 (20210G>A), FV (1691G>A, Leiden) en HFE (C282Y en H63D) gene was ingesluit vir analise as gevolg van hul belangrike rol as genetiese bydraers tot die bogenoemde biologiese prosesse. ‗n Totaal van 178 pasiënte gediagnoseer met NAFLD en 75 kontroles is bestudeer deur gebruik te maak van direkte DNA volgordebepaling en ‗n RT-PCR metode vir mutasie opsporing. Twee pasiënte met verhoogde ferritien vlakke is ook as gevalle studies ingesluit. ‗n Beduidende assosiasie is gevind tussen HFE mutasies en verhoogde Alanien Transaminase (ALT) vlakke in die NAFLD studiepopulasie (p = 0.04) wat aanduidend is van ‗n subgroup van pasiënte wat die meeste baat sal vind uit genetiese toetsing om meer aggressiewe behandeling te rig op' n vroeër stadium. Die noodsaaklikheid van 'n geïntegreerde, stelsels-gebaseerde netwerk benadering is gewys om meer akkuraat te onderskei tussen Oorerflike Hemochromatose (HH) en Insulien Weerstand-geassosieerde Hepatiese Yster Oorlading (IR-HIO) sindroom in vetsugtige pasiënte. Die PSGT benadering tot persoonlike medisyne formuleer geen-gebaseerde intervensie programme aangepas tot die behoeftes van die pasiënt ek maak diagnose van KVS-subtipes en voorkoming van kumulatiewe risiko moontlik. Hierdie bevindinge ondersteun die kliniese nut van die KVS multi-geen toets om riglyne vir die risikobestuur van kroniese siektes soos NAFLD daar te stel. Die HFE mutasie opsporings komponent van hierdie toets is van besondere belang om 'n effektiewe strategie vir die behandeling van pasiënte met 'n mediese geskiedenis van KVS en/of hoë yster vlakke daar te stel.

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23

Visser, Marike. "An evaluation of the efficacy of antimicrobial peptides against grapevine pathogens." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6729.

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Thesis (MSc (Genetics))--University of Stellenbosch, 2011.
Includes bibliography
ENGLISH ABSTRACT: This study investigated the use of antimicrobial peptides (AMPs) as possible source of resistance against a range of pathogens in grapevine. Whilst the ultimate aim would be to express AMPs in grapevine, the development of transgenic grapevine is time consuming and therefore pre-screening of potential AMPs is necessary. These small molecules, of less than 50 amino acids in length, are expressed by almost all organisms as part of their non-specific defence system. In vitro pre-screening of AMP activity is valuable but is limited since the activity on artificial media may differ from the AMP activity in planta. These tests are also restricted to pathogens which can be cultured in vitro. These limitations can be overcome by using transient expression systems to determine the in planta activity of AMPs against pathogens of interest. In this study transient systems were used to express AMPs in developed plant tissue to test their efficacy against grapevine pathogens such as Agrobacterium vitis, Xylophilus ampelinus and aster yellows phytoplasma. Aster yellows phytoplasma, which was recently discovered in local vineyards, is known to cause extensive damage and therefore pose a great threat to the South African grapevine industry. To study the in planta effect of AMPs against the abovementioned pathogens, transient expression vectors were constructed expressing either of the AMPs D4E1 or Vv-AMP1. D4E1 is a synthetically designed AMP known to be active against bacteria and fungi, while Vv-AMP1, isolated from grapevine berries, has already shown activity against fungi. In a transient approach in grapevine, the expression of foreign genes from viral and non-viral vectors was confirmed by expression of the marker genes β-glucuronidase and Green Fluorescent Protein, while tissue-printing immunoassays confirmed viral replication and systemic spread in Nicotiana benthamiana. The viral vectors were based on the phloem-limited virus grapevine virus A. Only Agrobacterium-mediated 35S transient expression vectors were used for AMP in planta activity screening since the viral-mediated expression in grapevine was insufficient for screening against A. vitis and X. ampelinus as it was restricted to phloem tissues after whole-leaf infiltration. No phytoplasma-infected material could be established and as a result AMP activity screening was only performed against the A. vitis and X. ampelinus. Quantification of the bacteria was performed by qPCR. Vv-AMP1 did not show activity against either of the two bacteria in planta while D4E1 was found to be active against both. The observed in planta activity of D4E1 correlated with the in vitro activity as measured in an AMP plate bioassay. In contrast to in vitro screenings, the in planta AMP activity screening might give a more accurate representation of the potential antimicrobial activity of the peptide in a transgenic plant environment. This study proved that transient expression systems can be used as a pre-screening method of AMP activity in planta against grapevine pathogens, allowing the screening of various AMPs in a relatively short period of time before committing to transgenic grapevine development.
AFRIKAANSE OPSOMMING: Hierdie studie het die gebruik van antimikrobiese peptiede (AMPe) as 'n moontlik bron van weerstand teen 'n reeks van patogene in wingerd ondersoek. Alhoewel die uiteindelike doel sal wees om AMPe uit te druk in wingerd, is transgeniese wingerd ontwikkeling tydrowend en daarom is vooraf evaluering van potensiële AMPe nodig. Hierdie klein molekules, van minder as 50 aminosure in lengte, word uitgedruk deur amper alle organismes as deel van hul nie-spesifieke verdedigingsisteem. In vitro vooraf evaluering van AMP aktiwiteit is van waarde, maar is beperk aangesien die aktiwiteit op kunsmatige media mag verskil van die AMP-aktiwiteit in planta. Hierdie toetse is ook beperk tot patogene wat in vitro gekweek kan word. Hierdie beperkinge kan oorkom word deur gebruik te maak van tydelike uitdrukkingsisteme om die in planta aktiwiteit van AMPe te bepaal teen patogene van belang. In hierdie studie is tydelike uitdrukkingsisteme gebruik om AMPe uit te druk in ontwikkelde plantweefsel om hul effektiwiteite te toets teen wingerdpatogene soos Agrobacterium vitis, Xylophilus ampelinus en aster yellows fitoplasma. Aster yellows fitoplasmas, wat onlangs in plaaslike wingerde ontdek is, is bekend vir die uitgebreide skade wat hul aanrig en hou daarom 'n groot bedreiging in vir die Suid-Afrikaanse wingerd industrie. Om die in planta effek van AMPe teen die bogenoemde patogene te bestudeer is tydelike uitdrukkingsvektore ontwikkel wat die AMPe D4E1 of Vv-AMP1 uitdruk. D4E1 is 'n sinteties-ontwerpte AMP wat aktief is teen bakterieë en fungi, terwyl Vv-AMP1, wat uit druiwekorrels geïsoleer is, alreeds aktiwiteit teen fungi getoon het. In 'n tydelike uitdrukkingsbenadering in wingerd is die uitdrukking van transgene, vanaf virus of nie-virus gebaseerde vektore, bevestig deur die uitdrukking van die merker gene β-glukuronidase en die Groen Fluoresserende Proteïen, terwyl weefsel afdrukkings-immunotoetse virus replisering en sistemiese beweging in Nicotiana benthamiana bevestig het. Die virusvektore was gebaseer op die floëem-beperkte virus, wingerdvirus A. Slegs Agrobacterium-bemiddelde 35S tydelike uitdrukkingsvektore is gebruik om die AMP in planta aktiwiteit te bepaal aangesien die virus-bemiddelde uitdrukking in wingerd onvoldoende was vir evaluering teen A. vitis en X. ampelinus weens die beperking tot die floëem weefsel na infiltrering van die totale blaar. Geen fitoplasma geïnfekteerde materiaal kon gevestig word nie, en daarom is AMP aktiwiteitsevaluering slegs teen A. vitis en X. ampelinus uitgevoer. Kwantifisering van die bakterieë is deur middel van qPCR uitgevoer. Vv-AMP1 het geen aktiwiteit getoon teen enige van die bakterieë in planta nie, terwyl D4E1 aktief was teen beide. Die waargenome in planta aktiwiteit van D4E1 het ooreengestem met die in vitro aktiwiteit soos bepaal deur 'n AMP plaat bio-toets. In kontras tot in vitro evaluering kan die in planta AMP-aktiwiteit evaluering 'n meer akkurate voorspelling bied van die potensiële antimikrobiese aktiwiteite van die peptied in 'n transgeniese plant omgewing. Hierdie studie het bewys dat tydelike uitdrukkingsisteme gebruik kan word as 'n voorafgaande evalueringsmetode vir AMP in planta aktiwiteit teen wingerdpatogene, wat die evaluering van 'n verskeidenheid AMPe in 'n relatiewe kort tydperk toelaat voor verbintenis tot die ontwikkeling van transgeniese wingerd.

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Suelves, Caballol Núria. "Evaluation of therapeutic targets for the treatment of behavioral alterations and neuropathology in Huntington’s disease. The role of histone deacetylase 3 and p75 neurotrophin receptor." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/663911.

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Huntington’s disease (HD) is a rare genetic disorder caused by an aberrant expansion of a CAG trinucleotide in the huntingtin gene (Htt). The neuropathology of the disease is characterized by progressive neuronal dysfunction and degeneration in specific regions within the central nervous system, which causes a triad of symptoms including motor, cognitive and psychiatric features. Current treatments only alleviate some of these symptoms without preventing the inevitable neuropathological progression and, therefore, there is great need for finding new therapies that act at the root of the illness. Transcriptional dysregulation, somatic CAG repeat instability and neurotrophic signaling alterations appear early in HD and have been considered important underlying pathogenic mechanisms. Additionally, it has been recently suggested that HDAC3 and p75NTR could participate in some of these processes. Accordingly, the main aim of this thesis was to evaluate the potential therapeutic benefits of the pharmacological inhibition of HDAC3 and the genetic reduction of p75NTR in a knock-in mouse model of HD, termed HdhQ7/Q111. Our results have demonstrated that the selective inhibition of HDAC3 ameliorates cognitive deficits (motor learning and long-term memory alterations) in HdhQ7/Q111 mice by restoring the neuronal activity- dependent transcription of important memory-related genes, such as Arc and Nr4a2. This effect could be due to an increase in histone acetylation, leading to a relaxed DNA configuration, as well as an increase in CBP acetylation, potentially promoting its transcriptional activity. Besides, we have observed that chronic HDAC3 inhibition suppresses somatic CAG repeat expansions in Htt gene. Results of this thesis have shown that HDAC3 inhibition increases Msh2 acetylation at lysine 73, probably altering its DNA repair activity, which has been involved in promoting somatic CAG repeat length increases. Finally, our results have shown that p75NTR levels are increased in HdhQ7/Q111 mice from symptomatic stages. Interestingly, p75NTR normalization delays the onset of motor coordination alterations, several neuropathological HD hallmarks and the overall neurotrophic signaling imbalance in HdhQ7/Q111 mice, which comprise a reduction of the neurotrophin BDNF, a reduction and disrupted activation of its specific receptor, TrkB, and an overactivation of the p75NTR-dependent JNK signaling pathway. However, normalization of p75NTR levels at late disease stages is not able to prevent the loss of striatal integrity and motor coordination in KI mice. This might be the result of the unstoppable advance of other pathological mechanisms that do not depend on p75NTR expression. Therefore, a pharmacological strategy aimed to reduce the expression or activity of p75NTR in HD could provide some benefits at early stages of the disease but, as the pathogenic process progresses, the benefits would be limited. Collectively, our results have provided further insight into the contribution of transcriptional dysregulation, somatic CAG instability and neurotrophin signaling disturbances to HD neuropathological progression and highlight HDAC3 and p75NTR as promising therapeutic targets to correct these pathogenic mechanisms and ameliorate cognitive and motor behavioral impairments in HD.
La malaltia de Huntington (MH) és un trastorn neurodegeneratiu i hereditari que es caracteritza per la presència d’alteracions motrius, cognitives i psiquiàtriques. Actualment no existeix cap tractament que aconsegueixi frenar la progressió d’aquesta patologia, de manera que l’avaluació de dianes terapèutiques esdevé de vital importància. La desregulació transcripcional, l’expansió somàtica del triplet CAG i l’alteració de la senyalització neurotròfica s’han descrit com importants mecanismes subjacents i s’ha determinat que les proteïnes HDAC3 i p75NTR podrien promoure alguns d’aquests processos. Per això, en aquesta tesi hem avaluat els possibles beneficis resultants de la inhibició farmacològica de la HDAC3 o de la reducció genètica del receptor p75NTR en un model de ratolí de la MH, anomenat HdhQ7/Q111. Els nostres resultats han demostrat que la inhibició de la HDAC3 en ratolins HdhQ7/Q111 aporta millores cognitives degut a la prevenció de les alteracions transcripcionals. Aquest efecte podria ser conseqüència d’un increment de l’acetilació d’histones, promovent una conformació més relaxada de l’ADN, i d’un increment de l’acetilació de la proteïna CBP, estimulant la seva activitat transcripcional. A més, hem demostrat que la inhibició de la HDAC3 suprimeix l’expansió somàtica del triplet CAG en el gen mutat de la proteïna huntingtina, possiblement degut a que s’incrementen els nivells d’acetilació de la proteïna Msh2 en un residu que podria alterar la seva activitat, la qual s’ha vist recentment implicada en l’allargament del tram CAG. Per últim, els nostres resultats han determinat que la normalització del receptor p75NTR en els ratolins HdhQ7/Q111 endarrereix l’aparició de les alteracions en coordinació motora, coincidint amb una millora de diferents característiques neuropatològiques de la MH i amb una recuperació de l’alterada senyalització neurotròfica. No obstant, en etapes avançades de la malaltia, l’efecte d’altres mecanismes patogènics que ocorren de forma progressiva en la MH acaben anul·lant els efectes positius de la reducció en els nivells de p75NTR. Les evidències experimentals recopilades permeten concloure que les proteïnes HDAC3 i p75NTR participen en l’aparició de mecanismes patològics clau per a la correcta funció neuronal en diferents regions cerebrals i, per tant, representen prometedores dianes terapèutiques per tractar la simptomatologia motora i cognitiva de la MH.

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Du, Min. "A greenhouse screening method for resistance to gray leaf spot in maize." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/42953.

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Fernandes, Patricia Garani. "Aplicação da microtomografia computadorizada para a análise morfométrica bi e tridimensional na avaliação da perda óssea experimental em ratos." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/58/58132/tde-15072014-165529/.

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Introdução: A histomorfometria do osso é um dos métodos padronizados que pode ser utilizado para quantificar a microestrutura do osso trabecular. Existem muitos meios de acesso para conseguir a visualização dos defeitos ósseos no caso de um acometimento de doença periodontal, por exemplo. A extensão e morfologia da perda óssea alveolar podem ser acessadas e examinadas após confecção de retalhos mucoperiosteais em cirurgias periodontais ou através de exames radiográficos. A partir de então, a tecnologia da micro- CT tornou-se padrão ouro para avaliação da arquitetura 3D do osso trabecular; exibindo como uma de suas principais vantagens sua habilidade em proporcionar resultados quantitativos com pouco ou nenhum preparo da amostra e sem a sua destruição. Metodologia: Foram utilizados 40 ratos machos: ratos normotensos (WK) e espontaneamente hipertensos (SHR) foram divididos em grupos com doença periodontal induzida por ligaduras (DP), e grupos controle, em que a DP não foi induzida (C). Cada um desses quatro grupos foram divididos em 2 subgrupos, de acordo com o período de eutanásia, que foi realizada no 10° e no 21° dia do experimento, desse modo cada grupo teve um n=5. Os animais do grupo DP receberam ligadura com fio de algodão ao redor do primeiro molar inferior. Após a eutanásia todas as hemimandíbulas dos animais tiveram seu tecido mole removido através de processos químico e biológico a fim de proporcionar uma peça histológica preparada adequadamente para ser escaneada no microtomógrafo. Para realização da análise microtomográfica foi utilizado um aparelho modelo 1172 da fabricante SkyScan®. As amostras foram verificadas nos três planos espaciais através dos softwares CTAN®, DATA VIEWER® e CTVOX® que também foram utilizados para a visualização tridimensional, análise qualitativa e quantitativa da anatomia externa e interna do osso alveolar. Resultados: Os resultados das medidas lineares foram aqueles extraídos de uma imagem bidimensional de uma fatia única escolhida por ser a mais representativa para detectar a perda óssea alveolar. Para a quantificação dos parâmetros volumétricos foi realizada a avaliação em dois pontos distintos: a área da região de furca do M1 mandibular e a área da região interproximal entre M1 e M2 da mandíbula. De todos os parâmetros avaliados e analisados os mais representativos para detectar a perda óssea alveolar neste modelo de estudo foram: Furca e JCE-COV (junção cemento-esmalte crista óssea vestibular) em 2D (medidas lineares) e a relação entre a superfície óssea e o volume ósseo; relação entre o volume ósseo e o volume total; porosidade e densidade mineral óssea nos parâmetros em 3D (medidas volumétricas). Conclusão: A metodologia empregada mostrou ser eficiente para a caracterização da perda óssea alveolar nos grupos controle e doença periodontal. A região escolhida e o método de análise tem influência no resultado. Assim medidas lineares e medidas volumétricas de uma mesma amostra podem apresentar porcentagens diferentes em relação à perda óssea.
Introduction: The histomorphometry of bone is one of the standard methods that can be used to quantify the microstructure of the trabecular bone. There are many ways to get access to the visualization of bone defects in the case of onset of periodontal disease, for example. The extent and morphology of alveolar bone loss may be accessed and examined after making mucoperiosteais flaps in periodontal or through radiographic examinations surgeries. Since then, the technology of micro - CT has become the gold standard for evaluation of the 3D architecture of trabecular bone; showing as one of its main advantages its ability to provide quantitative results without destruction and with little or no sample preparation. Methodos: Normotensive rats (WK) and spontaneously hypertensive (SHR) were divided into groups of ligature-induced periodontal disease (PD), and control groups (C), where PD is not induced. 40 rats were used and each of these four groups were divided into 2 subgroups according to the time of euthanasia , which was held on the 10th and 21st day of the experiment , thus each group had an n = 5 . The animals in the PD group received ligature with cotton thread around the first molar. After euthanasia, all animals had their mandibles soft tissue removed through chemical and biological processes to provide a suitably prepared for micro-ct analysis. In order to perform the micro-CT analysis, a model 1172 device manufacturer of SkyScan® was used. The samples were observed in the three spatial planes through the CTAN®, DATA VIEWER® and CTVOX® softwares which were also used for threedimensional visualization, qualitative and quantitative analysis of the external and internal anatomy of the alveolar bone. Results: The results of linear measurements were those extracted from a twodimensional image of a single slice chosen for being the most representative for detecting bone loss. For quantification of the volumetric parameters were assessed at two different points: the area of the furcation region of the mandibular M1 and interproximal area of the region between M1 and M2 of the jaw. Of all the most representative in detecting alveolar bone loss in this model of study parameters were evaluated and analyzed : Furcation and cementum-enamel junction to the buccal bone crest = 2D (linear measurements) and the relationship between the bone surface and bone volume ; ratio of bone volume to the total volume ; porosity and bone mineral density in 3D parameters ( volumetric measurements). Conclusion: The methodology was efficient for the characterization of alveolar bone loss in the periodontal disease groups. The region chosen and method of analysis have affected the outcome. Thus, linear and volumetric measurements of the same sample may have different percentages in relation to bone loss.

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Nieto, Medina Daniela. "Genetic and environmental factors involved in the development of periodontal disease." Master's thesis, 2019. http://hdl.handle.net/10284/7688.

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The goal of this work was to make a search on the genetic and environmental factors involved in the development of periodontal disease, in order to have a better understanding and therefore be able to give a better treatment to our patients. One of the most common immune/inflammatory disease of infectious origin is the periodontitis. This disease can have a negative impact in health and life quality, since patients can lose their teeth. Chronic and aggressive periodontal diseases are complex diseases with multifactorial etiology, that result in the destruction of the supporting structures of teeth. The immune system of the host plays an important role in this process. As environmental risk factors are smoking habits, nutrients and food diet, obesity and involved metabolic syndromes, stress and depression. Concerning genetic risk factors, several studies show the existence of familial aggregation and polymorphisms of diverse genes as well as epigenetic changes have been associated with increased susceptibility to periodontitis.
O objetivo deste trabalho foi fazer uma pesquisa bibliográfica sobre os fatores genéticos e ambientais envolvidos no desenvolvimento da doença periodontal, de modo a uma melhor compreensão e, portanto, poder dar um melhor tratamento aos pacientes. A periodontite é uma das doenças imuno/inflamatórias mais comuns com origem infeciosa. Esta doença pode ter um impacto negativo na saúde e qualidade de vida, uma vez que os pacientes podem perder os dentes. Doenças periodontais crónica e agressiva são doenças complexas com etiologia multifatorial, que leva à destruição das estruturas de suporte dos dentes. O sistema imune do hospedeiro desempenha um papel importante neste processo. Como fatores ambientais estão os hábitos tabágicos, nutrientes e dieta alimentar, obesidade e síndromes metabólicos relacionados, stress e depressão. No que diz respeito a fatores de risco genéticos, vários estudos demonstram a existência de agregação familiar e polimorfismos de vários genes assim como alterações epigenéticas têm disso associados com aumento da suscetibilidade para periodontite.

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LIU, MING-DE, and 劉明德. "An evaluation of the biosynthesis of mono-HETEs and leukotrienes of periodontal disease tissue." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/97182065611634645136.

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Kalia, Vrinda. "Metabolic evaluation of genetic and environmental contributors to Alzheimer’s disease." Thesis, 2021. https://doi.org/10.7916/d8-fj0m-bn64.

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Understanding the effect of the environment on human health has benefited from progress made in measuring the exposome. High resolution mass spectrometry (HRMS) has made it possible to measure small molecules across a large dynamic range, allowing researchers to study the role of low abundance environmental toxicants in causing human disease, including examining their effects on biochemistry. Alzheimer’s disease is the most prevalent neurodegenerative disease in the world. While aging is the largest risk factor of the disease, evidence of risk factors for dementias show that lifestyle choices and the environment may modify disease onset and alter the projected prevalence. Observational epidemiological studies have linked exposure to the persistent pesticide dichlorodiphenytrichloroethane (DDT) with increased risk of Alzheimer’s disease (AD). In Chapter 2, using an aging cohort based in Washington Heights and Inwood in Northern Manhattan, I investigated systemic biochemical changes associated with Alzheimer’s disease (AD). Small molecules in plasma were measured in 59 AD cases and 60 healthy participants of African American, Caribbean Hispanic, and non-Hispanic white ancestry using untargeted liquid-chromatography–based ultra-high-resolution mass spectrometry. Metabolite differences between AD and healthy, the different ethnic groups and apolipoprotein E gene (APOE) ε allele status were analyzed. Untargeted network analysis identified pathways enriched by AD-associated metabolites. Then, in Chapter 3, using the genetically tractable nematode model Caenorhabditis elegans, I investigated whether DDT can exacerbate AD-related pathology. DDT is a persistent organic pollutant which, despite its ban in 1972, can be detected in the blood of most people in the U.S. I investigated whether DDT can exacerbate AD-related pathology using a transgenic C. elegans strain that expresses a mutant tau protein fragment that is prone to aggregation, as well as a mutant strain expressing a non-aggregating form of tau protein. DDT restricted the growth in all strains; however, the restriction was more severe in the aggregating tau transgenic strain. Further, I found that DDT exacerbates the inhibitory effects of aggregating tau protein on basal mitochondrial respiration, and increases the amount of time the worms spent curled/coiled. High-resolution metabolomics in the whole worm suggests that DDT reduces levels of several amino acids but increases levels of uric acid and adenosylselenohomocysteine. Surprisingly, developmental exposure to DDT blunts the lifespan reduction caused by aggregating tau protein suggesting a mitohormetic effect of the “double-hit” from DDT and aggregating tau protein or an antagonistic effect which could ultimately turn on lifespan extension pathways. Our data suggest that exposure to DDT likely exacerbates the mitochondrial inhibitory effects of aggregating tau protein in C. elegans. DDT may mimic some of the mitochondrial inhibitory effects induced by increased tau protein aggregation, suggesting that the genetic and environmental insult converge on a common mitochondrial inhibitory pathway, which has been associated with AD in several other studies. Finally, in Chapter 4, I determined changes in global metabolism associated with aggregating tau protein in both C. elegans and humans. We performed high-resolution metabolomic analysis on cerebrospinal fluid (CSF) and plasma obtained from patients of AD and mild cognitive impairment, and cognitively normal controls. Using a transgenic strain of C. elegans which expresses aggregating tau protein in all neurons, I studied the effect of aggregating tau protein on metabolism using high-resolution metabolomic analysis in the whole worm. In the population study, I found >300 features associated (p < 0.05) with phosphorylated tau levels in CSF. Metabolic pathway enrichment identified alterations in fatty acid and amino acid metabolism. Worms expressing aggregating tau showed >900 features altered. Pathway enrichment suggested alterations in glycerophospholipid, fatty acid and amino acid metabolism pathways. To determine which metabolic features are altered in both species, I analyzed annotated features for overlap. Five metabolites were concordant between human plasma and C. elegans, and four concordant between human CSF and C. elegans. Thus, in this analysis I provide evidence in support of using C. elegans to study changes in global metabolism associated with Alzheimer’s disease. In conclusion, using liquid and gas-based chromatography coupled with high-resolution mass spectrometry, we can measure levels of endogenous and exogenously derived small molecules in different biological matrices. By using the appropriate study design, we can identify candidate molecules and biochemical pathways associated with environmental exposures or disease in human populations. These candidates can be followed up by exposing an appropriate C. elegans strain: transgenic strains, mutant strains, or strains that are susceptible to RNAi based knockdown. Given their short life cycle and being amenable to high-throughput behavioral assays, they can readily provide functional and molecular readouts of the perturbation. The findings can provide leads for relevant policy around environmental exposures, understanding mechanisms of toxicity and disease, and identifying potential therapeutic targets.

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Ong, Marianne M. A. "Clinical evaluation of bioactive glass particles in treating periodontal intrabony defects a report submitted in partial fulfillment ... for the degree of Master of Science in Periodontics ... /." 1997. http://catalog.hathitrust.org/api/volumes/oclc/68799707.html.

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Barber, Maria Rosa Watson. "Evaluation of the BANA assay as a screening test for the detection of periodontopathic organisms in children (Treponema denticola, Bacteroides gingivalis, Bacteroides forsythus) a thesis submitted in partial fulfillment ... in pediatric dentistry ... /." 1989. http://books.google.com/books?id=KEo_AAAAMAAJ.

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Alshihayb, Talal. "An evaluation of potential sources of systematic error in the estimation of periodontal disease associations." Thesis, 2019. https://hdl.handle.net/2144/37098.

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AIM: To investigate the effect of different definitions of periodontitis, using partial-mouth measurements instead of full-mouth ones, and unmeasured confounders on periodontitis’ associations with diabetes and cardiovascular disease (CVD). METHODS: Adults 30-79 years with ≥1 or ≥2 teeth in the 2009-2014 National Health and Nutrition Examination Survey for study 1 or 2, respectively. For study 1: periodontitis was defined using different thresholds while for study 2: it was defined using the CDC/AAP 2007 categorical definition and continuous measures were estimated using mean clinical attachment loss (CAL), Estimates of periodontitis were derived based on the full-mouth protocol and three partial-mouth protocols (PMPs), including the Ramfjörd teeth, the Community Periodontal Index for Treatment Needs teeth, and the random half-mouth. Effects of exposure and outcome misclassification of periodontitis were evaluated in relation to diabetes. Diabetes and CVD were ascertained using self-report. Percent relative bias (%RB) was calculated by comparing the odds ratios/beta estimates obtained from the full-mouth and PMPs. Study 3 used the dental longitudinal study to look at the effects of simulated unmeasured confounders on survival analysis in the periodontitis-diabetes/CVD and diabetes-periodontitis associations. RESULTS: For study 1: the effects of clinical severity on the odds ratios were association dependent. Clinical measures and extent did not depend on the association. For study 2: percent relative bias was generally less than 10% for the severe categories while it tended to exceed 10% for moderate categories. Mean clinical attachment loss resulted in minimal bias. For study 3: presence of one source of unmeasured confounding (one confounder) showed that the diabetes-periodontitis association was robust to it unlike the periodontitis-diabetes/CVD associations. CONCLUSION: These sources played a role in the periodontitis-diabetes, periodontitis-CVD, and diabetes-periodontitis associations. The associations were affected differently by each source. Some of these sources of systematic errors may change the conclusions of the associations.
2021-10-10

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Lu, Yi-Fan. "Functional Evaluation of Causal Mutations Identified in Human Genetic Studies." Diss., 2016. http://hdl.handle.net/10161/12106.

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Human genetics has been experiencing a wave of genetic discoveries thanks to the development of several technologies, such as genome-wide association studies (GWAS), whole-exome sequencing, and whole genome sequencing. Despite the massive genetic discoveries of new variants associated with human diseases, several key challenges emerge following the genetic discovery. GWAS is known to be good at identifying the locus associated with the patient phenotype. However, the actually causal variants responsible for the phenotype are often elusive. Another challenge in human genetics is that even the causal mutations are already known, the underlying biological effect might remain largely ambiguous. Functional evaluation plays a key role to solve these key challenges in human genetics both to identify causal variants responsible for the phenotype, and to further develop the biological insights from the disease-causing mutations.

We adopted various methods to characterize the effects of variants identified in human genetic studies, including patient genetic and phenotypic data, RNA chemistry, molecular biology, virology, and multi-electrode array and primary neuronal culture systems. Chapter 1 is a broader introduction for the motivation and challenges for functional evaluation in human genetic studies, and the background of several genetics discoveries, such as hepatitis C treatment response, in which we performed functional characterization.

Chapter 2 focuses on the characterization of causal variants following the GWAS study for hepatitis C treatment response. We characterized a non-coding SNP (rs4803217) of IL28B (IFNL3) in high linkage disequilibrium (LD) with the discovery SNP identified in the GWAS. In this chapter, we used inter-disciplinary approaches to characterize rs4803217 on RNA structure, disease association, and protein translation.

Chapter 3 describes another avenue of functional characterization following GWAS focusing on the novel transcripts and proteins identified near the IL28B (IFNL3) locus. It has been recently speculated that this novel protein, which was named IFNL4, may affect the HCV treatment response and clearance. In this chapter, we used molecular biology, virology, and patient genetic and phenotypic data to further characterize and understand the biology of IFNL4. The efforts in chapter 2 and 3 provided new insights to the candidate causal variant(s) responsible for the GWAS for HCV treatment response, however, more evidence is still required to make claims for the exact causal roles of these variants for the GWAS association.

Chapter 4 aims to characterize a mutation already known to cause a disease (seizure) in a mouse model. We demonstrate the potential use of multi-electrode array (MEA) system for the functional characterization and drug testing on mutations found in neurological diseases, such as seizure. Functional characterization in neurological diseases is relatively challenging and available systematic tools are relatively limited. This chapter shows an exploratory research and example to establish a system for the broader use for functional characterization and translational opportunities for mutations found in neurological diseases.

Overall, this dissertation spans a range of challenges of functional evaluations in human genetics. It is expected that the functional characterization to understand human mutations will become more central in human genetics, because there are still many biological questions remaining to be answered after the explosion of human genetic discoveries. The recent advance in several technologies, including genome editing and pluripotent stem cells, is also expected to make new tools available for functional studies in human diseases.

Dissertation

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"Non-invasive evaluation of non-alcoholic fatty liver disease using biochemical and genetic markers." 2013. http://library.cuhk.edu.hk/record=b5884459.

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Shen, Jiayun.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2013.
Includes bibliographical references (leaves 166-199).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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Pratap, Siddharth. "In silico evaluation of DNA-pooled allelotyping versus individual genotyping for genome-wide association studies of complex disease." Diss., 2007. http://etd.library.vanderbilt.edu/ETD-db/available/etd-07202007-124602/.

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Moosani, Anita. "Evaluation of Oral Neutrophil Levels as a Quantitative Measure of Periodontal Inflammatory Load in Patients with Special Needs." Thesis, 2012. http://hdl.handle.net/1807/33456.

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Purpose: To validate and assess the feasibility of using an assay of oral neutrophils to measure periodontal inflammation in uncooperative patients with special needs. Methods: Periodontal examination and neutrophil counts derived from oral swabs were performed on patients with special needs having comprehensive dental treatment under general anaesthesia (GA). The conventional periodontal measurements were compared to neutrophil levels while patients were under GA, and later at their recall examination. Results: Forty-nine patients were assessed under GA and 30 (61%) returned for recall examination. Spearman’s correlation allowed for comparisons between periodontal parameters and oral neutrophil counts. Despite limited cooperation, it was possible to acquire neutrophils (using swabs) for all patients that presented for recall examination in the ambulatory dental clinic. Conclusions: Oral neutrophil levels correlated significantly with conventional parameters of gingival inflammation and may serve as a standardized method for clinical assessment of periodontal diseases in the special needs population.

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"An evaluation of the genetic components of bovine respiratory disease and its influence on production traits." IOWA STATE UNIVERSITY, 2008. http://pqdtopen.proquest.com/#viewpdf?dispub=1450154.

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Wang, Shi-Heng, and 王世亨. "Applications of hierarchical modeling on the evaluation of contextual effect and genetic effect for complex disease." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/19787561254423790951.

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博士
國立臺灣大學
流行病學與預防醫學研究所
99
In association studies of complex diseases, data are usually collected in a hierarchical way. Examples are matched case-control or family-based studies. Such nesting data contain multiple sources of variability including similarity within clustered observed values and between subjects in the same category of certain variable. These sources of variation can be explained properly in a hierarchical model. In this thesis, three different types of nesting data are considered: (1) individuals from the same area share similar environmental effect, (2) the group-level environmental effect depends on the individual-level genetic factor, and (3) genetic covariates are measured repeatedly for a family-based study. The first focus of this thesis is the environmental influence measured at the individual level, such as by personal characteristics and lifestyle choices, and at the group-level (called contextual variables), such as by community factors and degree of local area development. The contextual influence on individual health status may be direct effect, or it can modify the influence of individual-level factors. The first aim of this thesis is to examine the relationship between contextual variable, the availability of public facilities for habitual physical activity in the community, and metabolic syndrome in northern Taiwan, one of the most densely populated countries in the world. Subjects consisted of 14658 participants aged 40 years or older from 10 districts of Taoyuan County in a health check-up program in 2004–2005. Public facility for habitual physical activity included school campuses and parks. Multilevel logistic regression models were created to examine the effect on metabolic syndrome at both the individual and the contextual level using MLwiN software version 2.0. The addition of the contextual variable to the model that included individual characteristics led to a further reduction of 7.2% in the variance. Using the facility density level I as the reference, the odds ratios (95% confidence interval) of metabolic syndrome for levels II, III, and IV were 0.87 (0.71-1.07), 0.87 (0.68-1.12), and 0.78 (0.61-0.99), respectively, with the trend test reaching significance. Greater availability of free facilities for habitual physical activity in a district was associated with a lower risk of metabolic syndrome among its residents. The second of the thesis is to explore the cross-level gene-environment interaction. To examine the interaction between genes and contextual factors, traditional approaches usually adopt asymptotic tests to assess whether the interaction exists. Such tests are limited as they cannot evaluate or quantify the strength of difference in genetic effects across different clusters or categories of the contextual variable. A Bayesian hierarchical mixed-effects model can examine whether the genetic effect is modified by residential environment in a matched case-control metabolic syndrome study. The group-level contextual covariate, availability of exercise facilities, contains four categories, from low to high. Based on posterior samples from Markov chain Monte Carlo (MCMC) methods, the interaction between this group-level environmental condition and the individual-level genetic effect is evaluated by differences in allelic effects under various contextual categories. The Bayesian analysis indicates that the effect of rs1801282 on metabolic syndrome development is modified by the contextual environmental factor such that, even with the same genotype, living in a residential area with low availability of exercise facility may result in higher risk. This Bayesian hierarchical mixed-effects model provides a quantitative assessment for the cross-level interaction between genes and contextual variables. The third part of this thesis focused on the association between copy number variation (CNV), which was measured repeatedly, and schizophrenia. The study sample consisted of 607 families of schizophrenia individuals and their first-degree relatives. Here the correlation arises not only between family members but also within repeated CNV measurements. This Bayesian hierarchical model assigns integers in the probabilistic sense to the repeated-measured quantitatively copy numbers, and is able to test the association simultaneously between all variants under study. When collapsing all three CNVs, the posterior probability of risk was 80%, indicating a higher risk of schizophrenia. This model is useful for scientists who consider CNV for novel target genes identification.

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Magalhães, Miguel Bernardo Pereira Barbosa de. "Evaluation of the strategies used in the prevention of periodontal diseases in school health in Portugal." Master's thesis, 2018. http://hdl.handle.net/10284/7451.

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Objective: To evaluate the technical and scientific knowledge of healthcare providers, responsible for the National School Health Programme, in order to prevent plaque-induced gingivitis and periodontal disease. Methods: A questionnaire with 16 multiple-choice questions was developed and sent to all professionals responsible for the school health in the Centre Region of Portugal. The bibliographic search was performed on Pubmed platform. Results: Among a total of 41 professionals responsible for the school health area of the Centre Region of Portugal, 36 responses were obtained (88%). In this region, it is seen that the promotion of oral health is mainly done by nurses. Additionally, this study discloses that there is a lack of preparation of some professionals, especially doctors and nurses, in the prevention of plaque-induced gingivitis and periodontal disease. This lack of preparation is justified by a misunderstanding about the main etiological factor of both diseases, as well as their correlation. There are still some flaws in the knowledge of brushing techniques, recommendation of mouthwash solutions and there is less recommendation of interdental brushes. The preparation of parents, educators and children for the detection of symptoms of gingival inflammation also represent an important gap. Conclusion: The study reports a need of a greater diversity and reinforcement of the healthcare professionals in school health teams and an improvement of the co-operation between the different professionals (doctors, nurses, dentists and oral hygienists). It is necessary to educate these multidisciplinary teams about the aetiology of the diseases, consequences of their progression, associated systemic diseases and appropriate oral hygiene techniques. It is fundamental to instil the culture of prevention in oral health, enabling these professionals to instruct teachers, parents and children to acquire knowledge on the prevention and detection of gingivitis and periodontitis.
Objetivo: Avaliar os conhecimentos técnico-científicos que profissionais de saúde, responsáveis pelo Programa Nacional de Saúde Escolar, possuem para prevenir a gengivite e a doença periodontal. Métodos: Foi criado e enviado um questionário com 16 perguntas de escolha múltipla para todos os profissionais responsáveis pela saúde escolar na Região Centro de Portugal. A pesquisa bibliográfica foi realizada na plataforma Pubmed. Resultados: De um total de 41 profissionais responsáveis pela área da Saúde Escolar da Região Centro de Portugal, obtiveram-se 36 respostas (88%). Nesta região, constatou-se que a promoção da saúde oral escolar é realizada maioritariamente por enfermeiros. Este estudo revelou também uma fraca preparação de alguns profissionais, principalmente médicos e enfermeiros, na prevenção da gengivite induzida por placa bacteriana e da doença periodontal. Esta má preparação deve-se, nomeadamente, ao desconhecimento do principal fator etiológico de ambas as doenças, bem como da sua correlação. Constatam-se ainda falhas ao nível das técnicas de escovagem, aconselhamento de soluções de bochecho e pouca recomendação de escovilhão interdentário. A preparação para a deteção dos sintomas de inflamação gengival dos pais, educadores e crianças é também uma lacuna existente. Conclusão: O estudo realizado demonstra a necessidade de uma maior diversificação e reforço de profissionais que compõem as equipas da saúde escolar e de uma melhoria da intercolaboração entre os diversos profissionais (médicos, enfermeiros, dentistas e higienistas orais). É necessário educar estas equipas multidisciplinares quanto à etiologia das doenças em estudo, consequências da sua progressão, doenças sistémicas associadas e técnicas de higiene oral apropriadas. É ainda fundamental incutir uma cultura de prevenção na área da saúde oral, capacitando estes profissionais para instruírem os professores, pais e crianças a adquirirem conhecimentos sobre prevenção de gengivite e periodontite.

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Torres, Alberto Rosmaninho Maçães. "Evaluation of the strategies and techniques used in the prevention and decrease of periodontal diseases by oral health care providers in schools." Master's thesis, 2017. http://hdl.handle.net/10284/6452.

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Objetivo: Perceber que conhecimentos possuem os profissionais responsáveis pela saúde escolar para prevenir e detetar gengivite induzida por placa bacteriana. Métodos: Foi elaborado um questionário com 16 perguntas de escolha múltipla, o qual foi enviado por email para todos os profissionais responsáveis pela saúde escolar da Região Norte de Portugal. Resultados: De um total de 66 profissionais responsáveis por a área de saúde escolar da região norte de Portugal, obteve-se 30 respostas (45,5%). Verificou-se que na região norte, a promoção de saúde oral escolar é realizada maioritariamente por enfermeiros. O estudo realizado demonstra um défice de preparação dos enfermeiros na prevenção de gengivite induzida por placa bacteriana. Verifica-se um possível desconhecimento quanto ao fator causal da doença bem como a sua possível progressão para periodontite. Constata-se falhas na preparação dos pais, educadores e crianças para detenção de sintomas de inflamação gengival e desconhecimento nas vantagens da utilização de escovilhão interdentário e em relação a soluções de bochecho à base de clorexidina. Conclusão: O estudo realizado demonstra a necessidade de uma maior comunicação entre dentista e enfermeiro. É necessário preparar estes profissionais em relação à etiologia da doença, consequências da sua progressão, doenças sistémicas associadas e técnicas de higiene oral apropriadas. É importante capacitar os enfermeiros para que possam instruir os professores, pais e crianças a adquirirem conhecimentos simples de prevenção e deteção de gengivite.
Objective: To understand what knowledge oral health care providers have to prevent and detect plaque-induced gingivitis. Methods: A questionnaire was developed with 16 multiple-choice questions and checkboxes answers, which was sent by email to all professionals responsible for school health in the Northern Region of Portugal. Results: Among 66 professionals responsible for the school health area of the northern region of Portugal, 30 answers (45.5%) were obtained. It was verified that, in the northern region, the promotion of oral health at school is carried out mainly by nurses. The study shows a lack of preparation from nurses relatively to the prevention of plaque-induced gingivitis. There is a possible lack of knowledge about the causal factor of the disease as well as its possible progression to periodontitis. Failure to prepare parents, educators and children for gingival inflammation symptoms and lack of knowledge of the advantages of using interdental brush and chlorhexidine-based mouthwash solutions are reported. Conclusion: The study shows the need for greater communication between dentists and nurses. It is necessary to prepare the latter in relation to the etiology of the disease, consequences of its progression, associated systemic diseases and appropriate oral hygiene techniques. It is important to train nurses so that they can instruct teachers, parents and children to acquire simple knowledge to prevent and detect gingivitis.

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Shieh, An-Tay. "Evaluation of a GTR-based root coverage procedure utilizing an absorbable collagen membrane thesis submitted in partial fulfillment ... for the degree of Master of Science in Periodontics ... /." 1996. http://catalog.hathitrust.org/api/volumes/oclc/68798517.html.

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Dugger, Sarah Anne. "Evaluation of a precision medicine approach for hnRNP U-related developmental epileptic encephalopathy using a mouse model of disease." Thesis, 2020. https://doi.org/10.7916/d8-qevc-mw16.

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Mutations in genes that cause transcriptional dysregulation, such as genes that encode DNA and RNA-binding proteins (RNABPs), are a well-described cause of neurodevelopmental syndromes such as autism and epilepsy. Heterozygous de novo mutations involving the gene HNRNPU, which encodes the heterogeneous nuclear ribonuclear protein U, have been implicated in a neurodevelopmental syndrome most commonly characterized by epileptic encephalopathy. Although hnRNP U is a highly-abundant and ubiquitously-expressed DNA- and RNA-binding protein involved in a variety of important nuclear processes—most notably gene expression regulation—the role it plays in neurological disease is unclear and has yet to be studied. The work presented here examines a precision medicine approach for epilepsies thought to have a transcriptomic basis, starting with a thorough neurophysiological characterization of a heterozygous loss-of-function Hnrnpu mouse model (Hnrnpu+/113DEL), followed by a comprehensive and region-specific single-cell transcriptomic study, and finally the validation of implicated brain regions. Characterization of the Hnrnpu+/113DEL mouse line revealed an increased susceptibility to seizures in Hnrnpu+/113DEL mice, along with an increased perinatal mortality, global developmental delay and gait abnormalities. Gene expression profiling, including bulk RNA-sequencing of neocortex and single cell RNA-sequencing of both neocortex and hippocampus, revealed widespread, yet modest, dysregulation of gene expression that was largely inversely correlated to gene-length, and involved important, neurodevelopmental disease genes. In particular, pyramidal neurons of the subiculum displayed greater transcriptional burden upon heterozygous loss of Hnrnpu, with the known epilepsy gene Mef2c as a clear outlier showing greater than 50% reduction in expression. Follow-up investigation into whether this region- and cell-type specific gene dysregulation correlated to differences in neuronal function using c-Fos immunostaining, revealed an overall decrease in neuronal activity within the ventral subiculum in Hnrnpu+/113DEL mice. In summary, our data validates the presence of neurodevelopmental defects upon heterozygous loss of Hnrnpu and supports the notion of transcriptional dysregulation as a likely contributing factor to hnRNP U-related disease, possibly through the dysfunction of subiculum-derived excitatory neurons. Future studies evaluating the relationship between reduced activity within the ventral subiculum and hnRNP U disease phenotypes are an important next step, and may serve as the basis for targeted therapeutic discovery.

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Stoddard, Sara L. "Evaluation and genetic analysis of wheat streak mosaic virus resistance in wheat germplasm by symptomatology, enzyme-linked immunosorbent assay, and slot-blot hybridization." 1986. http://hdl.handle.net/2097/22195.

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Sawatsky, W. M. "Evaluation of screening techniques for resistance to Leptosphaeria maculans and genetic studies of resistance to the disease in Brassica napus." 1989. http://hdl.handle.net/1993/17079.

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Bailey, Jason A. "EVALUATION OF GENE REGULATION AND THERAPEUTIC DRUGS RELATED TO ALZHEIMER’S DISEASE IN DEGENERATING PRIMARY CEREBROCORTICAL CULTURES." Thesis, 2012. http://hdl.handle.net/1805/2741.

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Indiana University-Purdue University Indianapolis (IUPUI)
Alzheimer’s disease (AD) is a neurological disorder defined by the presence of plaques comprised mostly of amyloid-β (Aβ), and neurofibrillary tangles consisting of hyperphosphorylated microtubule associated protein tau (MAPT). AD is also characterized by widespread synapse loss and degeneration followed by death of neurons in the brain. Inflammatory processes, such as glial activation, are also implicated. In order to study mechanisms of neurodegeneration and evaluate potential therapeutic agents that could slow or reverse this process, a tissue culture system was developed based on primary embryonic cerebrocortical neurons. This culture system was observed to exhibit time-dependent neurodegeneration, glial proliferation, and synaptic marker loss consistent with AD-affected brains. The regulatory promoter regions of several genes implicated in AD, including the Aβ precursor protein (APP), β-amyloid cleaving enzyme (BACE1), and MAPT, were studied in this culture model. The MAPT gene promoter activity followed the pattern of neuronal maturation and degeneration quite closely, increasing in the initial phase of the tissue culture, then reducing markedly during neurodegeneration while APP and BACE1 gene promoters remained active. Deletion series of these promoters were tested to give an initial indication of the active regions of the gene promoter regions. Furthermore, the effects of exogenous Aβ and overexpression of p25, which are two possible pathogenic mechanisms of gene regulation in AD, were studied. Response to Aβ varied between the promoters and by length of the Aβ fragment used. Overexpression of p25 increased MAPT, but not APP or BACE1, promoter activity. This neurodegeneration model was also used to study the putative neuroprotective action of the NMDA receptor antagonist memantine. Treatment with memantine prevented loss of synaptic markers and preserved neuronal morphology, while having no apparent effect on glial activation. The protective action on synaptic markers was also observed with two other structurally distinct NMDA receptor antagonists, suggesting that the effects of memantine are produced by its action on the NMDA receptor. It is concluded that this tissue culture model will be useful for the study of gene regulation and therapeutic agents for neurodegeneration, and that the efficacy of memantine may result from preservation of synaptic connections in the brain.

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Maritz, Inge. "Evaluation of polygalacturonase-inhibiting protein (PGIP)-mediated resistance against Verticillium dahliae, a fungal pathogen of potato." Diss., 2003. http://hdl.handle.net/2263/25887.

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Polygalacturonase-inhibiting proteins (PGIPs) are plant proteins believed to playa role in the defence against pathogenic fungi. In this study. it was hypothesized that apple PGIPI could be used to confer enhanced resistance against Verticillium-wilt. a major disease of potato caused by the fungus Verticillillm dahliae. Transgenic lines containing the apple pgip1 gene under control of the enhanced CaMV 35S (e35S) promoter had been generated previously. Stable integration of the transgene into the potato genome was shown by the polymerase chain reaction (PCR) and Southern blot with a DIG¬labelled apple pgip1 fragment as probe. Polygalacturonase (PG)-inhibiting assays (the agarose diffusion assay and reducing sugar assays) were employed to investigate the inhibiting activity of apple PGIP I extracts, prepared from the transgenic potato lines. on the PGs secreted by V. dahliae grown on pectin medium. Inhibition was successful for all but one of the transgenic lines. Active PGIPI was expressed in the leaves of in vitro- and glasshouse grown plants, as well as in roots of in vitro-grown plants. Due to the success of the in vitro inhibition results. it was anticipated that the apple pgip1 transgene would protect the transgenic lines against Verticillium-wilt in a subsequent glasshouse trial. The transgenic lines and untransformed BP I potato control were planted in soil inoculated with V. dahliae microsclerotia and control soil. Assessments of the visual symptoms of yellowing and wilt were made on a scale of 1-5. Colonisation of stem sections was determined by plating onto potato dextrose agar plates. Disease index values were calculated from the symptom and colonisation data. Analysis of variance indicated six lines to be significantly different from the rest when grown in the inoculated soil, but five of them also showed significantly slower senescence symptoms when grown in the control soil. It is proposed that the physiological effect of an extended juvenile phase resulted in the apparent increased disease resistance. This could be caused by transformation or tissue culture¬-induced somaclonal variation of the potato plants. The hypothesis that transformation of the apple pgip1 gene into potato would confer enhanced resistance against Verticillium-wilt was not supported by the data that was obtained. Expression of antifungal genes by pathogen-inducible promoters is a valuable strategy in the development of disease resistant crops of importance. A construct containing the apple pgipl gene under control of the pathogen-inducible gst1 promoter from Arabidopsis thaliana (L.) Heynh was generated. Agrobacterium tumefaciens GV31OI(pMP90RK) was transfonned with the plant transformation vector pCAMBIA2300 containing the gst1 and e35S promoter-pgip1 inserts. A. thaliana was transformed using the floral-dip method, and putative transgenic progeny were selected by kanamycin selection of the seeds. PCR verified the insertion of the transgene into the genomes of T2 and T3 lines. Gene expression from the two promoters was compared by performing PGIP extractions and the agarose diffusion assay. The gst1 promoter was active even without induction by methyl-salicylate. Both constructs led to the expression of active apple PGIP1 against V. dahliae PG in the heterologous plant A. thaliana.
Dissertation (MSc (Plant Biotechnology))--University of Pretoria, 2006.
Plant Science
unrestricted

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Guinan, Kimberly. "Economic evaluation of a new genetic risk score to prevent nephropathies in type-2 diabetic patients." Thesis, 2019. http://hdl.handle.net/1866/24690.

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Un score de risque polygénique (SRP) a été mis au point pour permettre une prédiction précoce du risque de néphropathie chez les patients atteints de diabète de type-2 (DT2). Le but de cette étude était d’évaluer l’impact économique de l’implantation du SRP pour la prévention de la néphropathie chez les patients atteints du DT2, par rapport aux méthodes de dépistage habituelles au Canada. Tout d’abord, une revue systématique de la littérature a été effectuée pour examiner les évaluations économiques publiées sur le DT2 et la néphropathie. Les principales techniques de modélisation observées dans cette revue ont été utilisées pour réaliser une analyse coût-utilité à l’aide d’un modèle de Markov. Les états de santé du modèle étaient la pré-insuffisance rénale (pré-IR), l’IR et le décès. Les paramètres d’efficacité du modèle ont été basés sur les résultats de l’étude ADVANCE. Les analyses ont été menées selon une perspective du système de soins et une perspective sociétale. Sur un horizon temporel de la vie entière du patient, le SRP était une stratégie dominante par rapport aux méthodes de dépistage habituelles, selon les deux perspectives choisies. En effet, le SRP était moins coûteux et plus efficace en termes d’années de vie ajustée en fonction de la qualité, par rapport aux techniques de dépistage usuelles. Les analyses de sensibilité déterministe et probabiliste ont démontré que les résultats demeurent dominants dans la majorité des simulations. Cette évaluation économique démontre que l’adoption du SRP permettrait de réduire les coûts et d’améliorer la qualité de vie des patients.
The current screening method for diabetic nephropathy (DN) is based upon the detection of urinary albumin and the decline of estimated glomerular filtration rate, which occurs relatively late in the course of the disease. A polygenic risk score (PRS) was developed for early prediction of the risk for type 2 diabetes (T2D) patients who experience DN. The aim of this study was to assess the economic impact of the implementation of the PRS for the prevention of DN in T2D patients, compared to usual screening methods in Canada. First, a systematic literature review was conducted to examine all published economic evaluations in T2D and DN. The main trends in modelling technics obtained from this review were used to conduct a cost-utility analysis using a Markov model. Health states include pre-end-stage renal disease (Pre-ESRD), ESRD and death. Model efficacy parameters were based on prediction of outcome data by polygenic-risk testing of the ADVANCE trial. Analyses were conducted from Canadian healthcare and societal perspectives. Over a lifetime horizon, the PRS was a dominant strategy compared to usual screening methods, from both a healthcare system and societal perspective. In other words, the PRS was less expensive and more effective in terms of quality-adjusted life years compared to usual screening technics. Deterministic and probabilistic sensitivity analyses showed that results remained dominant in the majority of simulations. This economic evaluation demonstrates that the adoption of the PRS would not only be cost saving but would also help prevent ESRD and improve patients’ quality of life.

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Meehan, Mitchell Elwin. "A comparison of techniques for screening for resistance to the chinch bug, Blissus leucopterus leucopterus (Say), in sorghum." 1985. http://hdl.handle.net/2097/27497.

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Khoo, Joleyn Yean Chern. "The role of the Borrelia oxidative stress regulator protein in virulence gene expression of the Lyme disease spirochete." Thesis, 2014. http://hdl.handle.net/1805/4037.

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Indiana University-Purdue University Indianapolis (IUPUI)
The Lyme disease agent, Borrelia burgdorferi, has a complex system that allows it to thrive in the harsh and distinct environments of its tick vector and mammalian host. Although it has been known for some time that the Borrelia oxidative stress regulator protein (BosR) plays a necessary role in mammalian infectivity and functions as a transcriptional regulator of alternative sigma factor RpoS, very little is known about its mechanism of action, other than the suggestion that BosR activates rpoS transcription by binding to certain upstream regions of the gene. In our studies, we performed protein degradation assays and luciferase reporter assays for further understanding of BosR function. Our preliminary findings suggest that BosR is post-transcriptionally regulated by an unknown protease and may not need to bind to any rpoS upstream regions in order to activate transcription. We also describe the construction of luciferase reporter systems that will shed light on BosR’s mechanism of action. We postulate the provocative possibility that unlike its homologs Fur and PerR in other bacterial systems, BosR may not utilize a DNA-binding mechanism in order to fulfill its role as a transcriptional regulator to modulate virulence gene expression.

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Trotta, Gianpaolo Francesco. "Intelligent Systems for Industry 4.0: Decision Support Systems and Immersive Human-Computer Interfaces." Doctoral thesis, 2019. http://hdl.handle.net/11589/161178.

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Lo scopo di questa tesi di dottorato è la progettazione, lo sviluppo e la valutazione di sistemi intelligenti per Industria 4.0. Dato l'interesse verso soluzioni innovative per servizi avanzati nei settori manifatturiero e bioingegneristico, l'obiettivo delle soluzioni proposte è la progettazione, lo sviluppo e la valutazione di sistemi intelligenti che seguono i quattro principi principali dell'Industria 4.0: interoperabilità, informazioni trasparenti, assistenza tecnica e decisioni decentrate. L'attenzione si concentra principalmente sul principio dell'assistenza tecnica, che descrive come i sistemi di assistenza potrebbero supportare gli esseri umani aggregando e visualizzando le informazioni attraverso interfacce uomo-computer coinvolgenti e innovative utilizzate per prendere decisioni informate, risolvere problemi urgenti e svolgere una serie di compiti spiacevoli. Nel settore manifatturiero, il tempo di addestramento di operatori su di una particolare mansione, piuttosto che il tempo per risolvere un problema di manutenzione, gioca un ruolo vitale nell'efficienza e nell'efficacia di un ambiente industriale. Pertanto, considerando i principi innovativi di Industria 4.0, la principale domanda di ricerca è la seguente: come dovremmo progettare e sviluppare un'interfaccia uomo-computer immersiva per consentire agli operatori, senza alcun dispositivo indossabile, di apprendere rapidamente i compiti richiesti durante il loro lavoro? È stato studiato un caso d'uso basato sull'applicazione di un sistema di realtà aumentata spaziale (o proiettata). Questo lavoro di dottorato presenta gli approcci utilizzati per progettare questo particolare tipo di sistemi e implementare gli algoritmi utilizzati per riconoscere e tracciare gli oggetti direttamente sul banco da lavoro. Inoltre, in un ambiente industriale, la valutazione delle posizioni eseguite dagli operatori durante il loro lavoro ha un impatto cruciale sulla salute degli operatori e, in questo caso, sull'efficienza e l'efficacia dei processi industriali. Pertanto, la domanda centrale di ricerca è la seguente: come dobbiamo implementare e convalidare un sistema che valuti in tempo reale posture a rischio? La tesi di dottorato presenta l'approccio adottato per progettare il sistema utilizzando un sensore di profondità della telecamera, come Kinect v2, e per convalidarlo utilizzando un sistema di visione standardizzato utilizzato per l'analisi del movimento in aminazioni cliniche, come la piattaforma BTS. Il campo della bioingegneria industriale è strettamente correlato all'area di produzione, riguardante sia le tecnologie che le tecniche utilizzate per progettare e implementare sistemi per supportare i medici durante gli esami clinici e diagnostici o le operazioni chirurgiche. Nel contesto di questo lavoro di dottorato, sono stati implementati algoritmi di visione artificiale e sistemi di supporto alle decisioni in grado di rilevare e riconoscere i tumori partendo da immagini mediche, noti anche come diagnosi assistita dal computer per supportare i medici nelle loro decisioni diagnostiche. Inoltre, i segnali acquisiti utilizzando i sensori durante l'esame clinico sono opportunamente elaborati per essere usati nell'addestramento di sistemi di supporto decisionale che riconosano la gravità di certe malattie neurologiche. In questo modo, i problemi creati dalla natura osservativa di questo tipo di esame sono presenti e i sistemi implementati aiutano i medici a prendere decisioni più precise sulla gravità della malattia. Infine, nel mondo reale sono state progettate e sviluppate interfacce immersive uomo-computer utilizzate per informazioni che si sovrappongono in modo compresivo (ad es. Ricostruzione 3D di un tumore) per aiutare i chirurghi durante le operazioni chirurgiche. Dopo un'introduzione di Industry 4.0, la dissertazione è organizzata in due parti principali, che trattano i due argomenti trattati durante la ricerca di dottorato. La tesi termina con le conclusioni e i lavori futuri. In dettaglio, il secondo capitolo, intitolato Design, sviluppo e valutazione di interfacce uomo computer intelligenti, immersive e innovative in uno scenario industriale per servizi di manutenzione, è relativo alla discussione di tecniche e tecnologie immersive e innovative utilizzate per migliorare la qualità del lavoro, riguardante le posture sul posto di lavoro e il tempo necessario per completare un compito di formazione. Il terzo capitolo, intitolato Intelligent Support in Industrial Bioingegnering: Decision Support Systems and Immersive Human-Computer Interface Application, è relativo alla discussione dei sistemi di supporto decisionale per supportare i clinici durante gli esami diagnostici o clinici e un sistema di realtà mista per supportare i chirurghi durante le operazioni chirurgiche.
The aim of this PhD thesis is the design, development and evaluation of intelligent systems for Industry 4.0. In particular, because of the interest in innovative solutions for advanced services in manufacturing and bioengineering fields, the goal of the pro-posed solutions is the design, development and evaluation of intelligent systems fol-lowing the four main principles of Industry 4.0: interoperability, information transpar-ency, technical assistance and decentralized decisions. The focus is mainly on the technical assistance principle, which describes how assistance systems could support humans by comprehensively aggregating and visualising information via immersive and innovative human-computer interfaces when making informed decisions, solving urgent problems and conducting a range of unpleasant tasks. In manufacturing, the time to train operators for a task, rather than the time to solve a maintenance problem for a component on a manual working station, plays a vital role in the efficiency and efficacy of an industrial environment. Therefore, considering the innovative principles of Industry 4.0, the leading research question is as follows: How should we design and develop an immersive human-computer interface to allow the operators, without any wearable device, to quickly learn the tasks required during their work? A use case based on the application of a spatial (or projected) augmented reality system was investigated. This PhD work presents the approaches used to design the manual working station and to implement the algorithms used to recognise and track the objects on the station and opportunely project the information about a specific task. Moreover, in an industrial environment, the evaluation of postures performed by operators during their work has a crucial impact on the operators’ health and, in this case, on the efficiency and efficacy of industrial processes. Therefore, the central re-search question is as follows: How should we implement and validate a real-time sys-tem to detect awkward postures? This PhD dissertation presents the approach em-ployed to design the system using a depth camera sensor, such as Kinect v2, and to validate it using a standardised vision system used for motion analysis in clinical ex-aminations, such as the BTS platform. The industrial bioengineering field is strictly correlated to the manufacturing area, concerning both technologies and techniques used to design and implement systems to support physicians during clinical and diagnostic examinations or surgical operations. In the context of this PhD work, computer vision algorithms and decision support sys-tems able to detect and recognise tumours starting from medical images, also known as computer-aided diagnosis frameworks, were implemented to support physicians in their diagnostic decisions. Moreover, signals acquired using sensors during the clinical examination are opportunely elaborated to use them for training decision support sys-tems that recognise the severity of the certain neurological diseases. In this way, the problems created by the observational nature of this kind of examination are fixed, and the systems implemented help the clinicians make more precise decisions about disease severity. Finally, immersive human-computer interfaces used for comprehen-sively overlapping information (e.g., 3D reconstruction of a tumour) in the real world were designed and developed to help surgeons during surgical operations. After an introduction of Industry 4.0, the dissertation is organised into two main parts, which discuss the two topics covered during the PhD research. The dissertation ends with the conclusions and future works . In detail, the second chapter, entitled Design, Development and Evaluation of Intelligent, Immersive and Innovation Hu-man-Computer interfaces in an Industrial Scenario for Maintenance Services, is relat-ed to the discussion of immersive and innovative techniques and technologies used to improve the work quality, concerning postures in the workplace and time to finish a training task. The third chapter, entitled Intelligent Support in Industrial Bioengineer-ing: Decision Support Systems and Immersive Human-Computer Interfaces Applica-tion, is related to the discussion of decision support systems to support clinicians dur-ing diagnostic or clinical examinations and a mixed reality system to support surgeons during surgical operations.

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