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GuimarÃes, SÃrgio Botelho. "In vivo acute changes in ATP and glucose concentrations in the rat testicles following unilateral torsion: experimental study." Universidade Federal do CearÃ, 2002. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=21.
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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel SuperiorSpematic cord torsion is one of the more common surgical urological emergencies in childhood. An experimental study has been conducted to investigate acute changes in testicular concentrations of ATP and glucose following one-hour unilateral 720Â testicular torsion. Sixty prepubertal male Wistar rats were distributed into two groups: Group 2(Ischemia) and Group 1(Sham operated). Each group(n=30) was divided into 5 subgroups (n=6). All animals were subjected to right testicular torsion of 720Â. The testicular torsion of animals from Group 1 was immediately corrected. Group 2 animals had their testicular torsion lasting one hour followed by detorsion. Testicles were collected and arterial blood samples taken from abdominal aorta of each animal subgroup at the and of ischemic period or one hour after sham operation and 0.5, 1,6 and 24 hours later. ATP and glucose concentrations were significantly decreased (p<0,05) in ischemia group as compared to sham group at the end of ischemic period. There was no difference in glycemia when comparing ischemic versus sham-operated rats. Glucose concentrations were significantly increase (p<0,05) in ipsilateral testis of sham-operated rats No significant change in ATP and glucose concentrations were found in the left testicle in comparasion to the ones measured in the rigth testicle of the same animal. The decrease in ATP and glucose concentrations may be explained by the reduction in blood flow to the torted testis imposed by torsion. The absence of significant contralateral alterations in the concentrations of ATP and glucose could be related to the limited time of isquemia imposed to the right testis. It is concluded that unilateral one-hour testicular torsion causes a decrease in ipsilateral testicular perfusion resulting in decresead testicular concentrations of glucose and ATP in the ipstelial (right) testicles and no alterations in the concentrations of glucose and ATP in the contraleral testicles. Simple testicle manipulation (Sham Operation) causes a signficant increase in glucose concentrations in the ipsilateral(right)testis.
A torÃÃo do cordÃo espermÃtico à a emergÃncia geniturinÃria mais comum na idade pediÃtrica. Foram estudadas as alteraÃÃes metabÃlicas agudas nas concentraÃÃes testiculares de ATP e glicose apÃs uma hora de isquemia induzida por torÃÃo do cordÃo espermÃtico. Sessenta ratos wistar machos prÃ-pÃberes, foram distribuÃdos em 2 grupos de 30 animais cada e cada grupo em 5 subgrupos de 6 ratos. Os ratos do grupo 1 foram submetidos à torÃÃo seguida por distorÃÃo imediata (cirurgia simulada) do testÃculo direito. Os animais do grupo 2 foram submetidos à torÃÃo do testÃculo direito (720o) durante uma hora. Os animais dos diferentes subgrupos foram sacrificados 30 minutos, 1 hora, 6 horas e 24 horas apÃs a distorÃÃo ou realizaÃÃo da cirurgia simulada para a remoÃÃo dos testÃculos e coleta de amostra de sangue arterial. As alteraÃÃes das concentraÃÃes de glicose e ATP foram determinadas por mÃtodos enzimÃticos. Ocorreu queda significante (p<0,05) da concentraÃÃo de glicose e ATP no tempo 0 h, nos testiculos isquemiados. NÃo ocorreram alteraÃÃes na glicemia nem nas concentraÃÃes de glicose e ATP nos testÃculos contralaterais. Os animais submetidos à cirurgia simulada apresentaram aumento significante (p< 0,05) da concentraÃÃo de glicose no testÃculo ipsilateral quando comparada à concentraÃÃo de glicose no testÃculo esquerdo dos mesmos animais nos tempos 0 h e 24h. A diminuiÃÃo do fluxo sangÃÃneo em decorrÃncia da torÃÃo explica a reduÃÃo das concentraÃÃes de ATP e glicose nos testÃculos isquemiados. A ausÃncia de alteraÃÃes nas concentraÃÃes de ATP e glicose nos testÃculos contralaterais (esquerdos) poderia ser uma decorrÃncia do reduzido tempo de isquemia imposto ao testÃculo ipsilateral (direito). Concluiu-se que a torÃÃo testicular unilateral de 720o, por uma hora, induz uma reduÃÃo significante (p < 0,05) das concentraÃÃes testiculares de ATP e de glicose no testÃculo isquemiado sem alteraÃÃes correspondentes da glicemia. A simples manipulaÃÃo do testÃculo direito (cirurgia simulada) induz um aumento da concentraÃÃo de glicose testicular.
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Ohlson, Lena. "In vivo studies of cell cycle regulating proteins in rats during liver regeneration and during promotion of liver carcinogenesis /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-980-3/.
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Speranzini, Léa Beltrão de Medeiros. "A atividade mioelétrica colônica em ratas sob diferentes estados hormonais: influência de altos níveis de estrógeno, progesterona e da prenhez: estudo experimental in vivo." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/5/5147/tde-06022007-110719/.
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Sendo a constipação intestinal queixa freqüente em gestantes, procuramos verificar se o complexo hormonal da gestação, e em especial a progesterona, diminui a atividade muscular colônica. Para tanto, estudamos in vivo o registro do sinal mioelétrico, sob diferentes estados hormonais, em quatro pontos do cólon de ratas: ascendente proximal, ascendente distal, médio e cólon descendente por meio de implante de eletrodos na camada sero-muscular colônica. As ratas foram divididas em 5 grupos: controle, ooforectomizadas, ooforectomizadas tratadas com estrógeno, ooforectomizadas tratadas com progesterona e ratas prenhes. Os resultados mostraram uma maior atividade elétrica no cólon proximal em ratas prenhes e nas pré-tratadas com progesterona. Nas ratas prenhes a duração da atividade elétrica máxima foi, de modo significante, maior em todas as distâncias quando comparada com ratas controle. Os resultados sugerem que in vivo a progesterona e o complexo hormonal da prenhez aumentam a atividade mioelétrica do cólon proximal e que a prenhez aumenta a duração da atividade elétrica máxima no cólon em cada distância estudada, levando à formação de fezes mais desidratadas. Progesterona e prenhez não devem ser responsabilizadas por hipomotilidade do cólon, uma das hipóteses que poderia explicar a constipação intestinal em gestantesThe aim of this study was to find out if the hormonal complex of pregnancy, especially progesterone, could be responsible for decreasing colon myoelectric activity in female rats. We analyzed the records of colon myoelectric activity in vivo using the method of musculoserosal implantation of electrodes in four regions of the colon: proximal ascendent colon, distal ascendent colon, medial colon and descendent colon. The rats were divided in five groups: control, ovariectomized, ovariectomized and treated with estrogen, ovariectomized and treated with progesterone and pregnant rats. The results showed a greater electric activity in the proximal colon in pregnant and progesterone pretreated rats. In pregnant rats the duration of maximum electric activity was significantly greater in all distances studied. The results suggest that in vivo progesterone and the hormonal complex of pregnancy increase myoelectric activity of the proximal colon, and that pregnancy increases the duration of the maximum electric activity of the colon in every distance studied leading to more dehydrated fecal material. Progesterone and pregnancy should not be responsible for colon hypomotility, one of the hypothesis that could explain intestinal constipation in pregnant women
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Sinno, Hani. "Role of collagen, complement C3, and C5 on cutaneous wound healing: topical formulation, preparation, and «in-vivo» evaluation in experimental rats." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66713.
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The growing rates of problematic wounds in the population and the subsequent increase in morbidity and mortality warrant further understanding of wound healing and the development of therapeutic agents targeted to alleviate these devastating concerns. The complement system is composed of bactericidal and hemolytic proteins that increase capillary leakage and inflammatory cell migration. It allows for an anaphylactic reaction and the recruitment of inflammatory cells. Fibroblast recruitment and subsequent collagen deposition in wounds is responsible for wound healing and is regulated by inflammatory cells. However, little is known about role the complement system may have on wound healing strength. This work investigates the effects of the topical application of collagen, complements C3 and C5 in varied formulations on the paired surgical skin incision rat model. These potential findings may help further enhance the understanding of wound healing and allow for a novel therapeutic approach for the treatment of patients.Les plaies aigues et chroniques sont associées à des taux de morbidité et mortalité importantes, et c'est pourquoi il est important de réaliser des études approfondies qui permettraient de développer des agents thérapeutiques qui stimulent la guérison de plaie. Le lien entre le système de complément et la guérison de plaies est encore méconnu. Le système de complément est composé de protéines bactéricides et hémolytiques qui augmentent la fuite capillaire tout en stimulant la migration de cellules. Il permet une réaction anaphylactique en recrutant des cellules inflammatoires telles que les fibroblastes suivis par la déposition de collagène au site de la plaie; ensemble celles-ci participent activement à la guérison et sont par la suite modulées par d'autres cellules inflammatoires. Cette étude analyse les effets de l'application topique de collagène, de compléments C3 et C5 sous diverses formes, au site de la plaie. Le modèle expérimental sélectionné a été réalisé par l'application d'une incision chirurgicale sur la peau dorsale du rat. Ces futurs résultats amélioreront notre compréhension de la guérison de plaies tout en permettant le développement d'une approche thérapeutique originale pour le traitement des patients atteints de plaies aigues et chroniques.
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Silva, Paula Regina Pereira. "Avaliação do potencial genotóxico e cancerígeno do lodo de estação de tratamento de esgoto (LETE) em sistemas experimentais in vivo." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5144/tde-13012011-151628/.
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A rápida oxidação da matéria orgânica dos solos tropicais é mais uma evidência da grande vantagem do uso de biossólidos como condicionadores, capazes de melhorar as características físicas, químicas e biológicas do solo com grandes reflexos na produtividade agrícola. Portanto, o presente projeto objetivou averiguar o potencial genotóxico e cancerígeno dos lotes do Lodo de Estação de Tratamento de Esgoto (LETE) gerado em uma ETE prédefinida na região da bacia hidrográfica Piracicaba, Capivari e Jundiaí (PCJ1). Estes dados poderão fornecer subsídios para a avaliação do risco das populações humanas e o meio ambiente expostas ao LETE. Foram utilizados 140 ratos Wistar machos com 8 semanas de idade, expostos, via ração, a concentrações de 10.000 e 50.000ppm de LETE, durante 6 e 8 semanas, com os iniciadores DEN (N-dietilnitrosamina) e DMH (1,2- dimetilhidrazina), conforme citado nos respectivos protocolos (Figuras 4 e 5). A avaliação toxicológica do lodo de esgoto desenvolvida pelo Núcleo de Avaliação do Impacto Ambiental Sobre a Saúde Humana (TOXICAM), enfocou os parâmetros toxicológicos, como seu potencial genotóxico, pelos testes do cometa e micronúcleo em sangue periférico e medula óssea e carcinogenicidade pelos ensaios de FCA e FHA. Os dois ensaios foram divididos em 4 grupos (FCA- GI=Controle Negativo, GII=Controle Positivo/DMH III=10.000ppmLETE e GIV=50.000ppmLETE); (FHAGI= Controle Negativo, GII=Controle Positivo/DEN, GIII=10.000ppmLETE e GIV=50.000ppmLETE). Entretanto, na 3ª semana foi realizada hepatectomia parcial em todos os animais dos respectivos grupos do ensaio de FHA. No teste do cometa foram utilizados 10 animais como controle positivo (controle interno - MNU-N-metil-N-nitrosourea), e 10 animais como controle negativo nos respectivos ensaios (FCA e FHA). Os testes em questão indicaram que o LETE não promove aumento do número de criptas aberrantes no cólon, número e área de focos de hepatócitos alterados no fígado, lesões no DNA (cometa), e também, não houve aumento de forma significativa a frequência de micronúcleo nas células, conforme as tabelas a seguir: 2.1(G=III e IV); 3.1(G=IV); 4(G=,III e IV); 5(G=III,IV e V); 6(G=III,IV e V); 7(G=IV e V). Em relação ao controle positivo. Estes dados poderão fornecer suporte na avaliação de risco da população humana e o meio ambiente, quando expostos ao lodo de estação de tratamento de esgoto.Fast oxidation of organic matter on tropical soils is another evidence of the great advantage of using biosolids as conditioners once they are able to improve biological, chemical and physical characteristics of the soil with remarkable consequences on agricultural productivity. Therefore, the present project aimed at verifying genotoxic and carcinogenic potential plots of sludge from sewage treatment plants in a pre-defined watershed region at Piracicaba, Capivari and Jundiaí (PCJ1). These data may provide support to evaluate risks on human populations and the environment exposed to sludge from sewage treatment plants. In the study, 140 Wistar male rats, 8 weekold, were used. They were exposed, via chow, to a 10.000 and 50.000 ppm concentration of sludge from sewage treatment plants during 6 to 8 weeks with DEN initiators (diethylnitrosamine) and DMH (1,2-dimethylhydrazine) as mentioned in protocols (Figures 4 and 5). Toxicological evaluation of LETE developed by Center of Evaluation of Environmental Impact on Human Health (TOXICAM) focused toxicological parameters with its genotoxic potential by comet and micronucleus assays on peripheral blood and bone marrow in Wistar rats and carcinogenicity using ACF and AHF assays. Both assays were divided into 4 groups (ACF- GI=Negative Control, GII=Positive Control/DMH III=10.000ppmLETE and GIV=50.000ppmLETE); (AHF-GI=Negative Control, GII=Positive Positive/DEN, GIII=10.000ppmLETE and GIV=50.000ppmLETE). Therefore, on the 3rd week partial hepatectomy was performed in every animal from AHF assays respective groups. assays and to FCA comet test, using MNU (N-methyl-N-nitrosourea) as positive control. The tests in question indicated that the SS not promote increased number of aberrant crypts in the colon, number and area of foci of altered hepatocytes in the liver, lesions in DNA (comet), and also, significantly increased the frequency of micronucleus in cells, according to the following tables 2.1(G=III and IV); 3.1(G=IV); 4(G=,III and IV); 5(G=III,IV and V); 6(G=III,IV and V); 7(G=IV and V). For the positive control. These data may provide support to evaluate risks on human populations and the environment exposed to sludge from sewage treatment plants.
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Menezes, Arteiro Queiroz. "Estudo de pulmões de ratos reperfundidos em um modelo experimental ex-vivo: comparação entre duas soluções de preservação (Perfadex® e Celsior®)." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/5/5156/tde-09082013-120744/.
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INTRODUÇÃO: A lesão de isquemia-reperfusão continua sendo considerada a maior causa de mortalidade relacionada ao transplante de pulmão e sua gravidade é influenciada por diversos fatores, dentre eles, a preservação pulmonar. OBJETIVO: Comparar duas soluções de preservação pulmonar, Perfadex® e Celsior®, quanto a capacidade de preservação de tecido pulmonar isquêmico. MÉTODOS: Sessenta pulmões de ratos preservados com Perfadex®, Celsior® ou solução salina após períodos de isquemia hipotérmica de 6 ou 12 horas, foram reperfundidos com sangue homólogo em modelo experimental ex-vivo durante 60 minutos consecutivos. A cada 10 minutos os dados de gasometria, hematócrito, mecânica ventilatória, hemodinâmica e peso do bloco cardiopulmonar foram registrados. Ao final da reperfusão o pulmão esquerdo foi pesado e acondicionado por 48h a 70oC para obtenção da razão peso úmido/peso seco, bem como amostras de tecido pulmonar foram retiradas para histopatologia, microscopia eletrônica e TUNEL. A análise estatística incluiu a comparação entre as soluções e os tempos de isquemia, utilizando ANOVA e Kruskall-Wallis. O nível de significância foi de 5%. RESULTADOS: A comparação entre as complacências de pulmões preservados com Celsior® e Perfadex® nos tempos de isquemia de 6 e 12 horas não apresentou significância estatística (p=0,161 e p=0,316, respectivamente). Os pulmões submetidos a 6 horas de isquemia apresentaram complacência pulmonar superior aos de 12 horas (Perfadex® p=0,02; Celsior® p=0,019; Salina p=0,016). Os valores de pressão arterial pulmonar foram semelhantes entre as três soluções nos dois tempos de isquemia, bem como na comparação entre os tempos de 6 e 12 horas, independente da solução. A Capacidade Relativa de Oxigenação não demonstrou diferença estatística entre as três soluções, independentemente do tempo de isquemia. Na comparação entre os dois tempos de isquemia, o desempenho da oxigenação foi significativamente pior nos pulmões preservados com salina por 12 horas (p=0,001). A razão peso úmido/peso seco não apresentou diferença estatística significante entre as três soluções nos dois tempos de isquemia, porém na comparação entre os tempos de isquemia, os pulmões preservados com Perfadex® apresentaram uma relação peso úmido/peso seco maior no tempo de isquemia mais longo (p=0,001). À microscopia óptica, pulmões preservados com salina apresentaram mais edema que os demais, independentemente do tempo de isquemia. A avaliação da apoptose celular através do método de TUNEL não mostrou diferença estatisticamente significativa na comparação entre os grupos. CONCLUSÃO: Os pulmões preservados com Perfadex® e Celsior® apresentaram desempenho similar em relação às trocas gasosas e parâmetros hemodinâmicos e de mecânica ventilatória. Os pulmões preservados com Perfadex® por 12 horas apresentaram mais edema. Os achados histopatológicos não diferiram entre os grupos estudadosINTRODUCTION: Ischemia-reperfusion injury remaisn the leading cause of mortality related to lung transplantation. Its severity is influenced by several factors including lung preservation. OBJECTIVE: To compare two lung preservation solutions, Perfadex® and Celsior® and its ability to preserve ischemic lung tissue. METHODS: Sixty rat lungs were preserved with Perfadex®, Celsior® or saline after a cold ischemic period of 6 or 12 hours and were then reperfused with homologous blood in an ex vivo experimental model for 60 consecutive minutes. At 10-minute intervals during reperfusion of the heart-lung blocks, data were collected for blood gases, hematocrit, mechanical ventilation, hemodynamic and the heart-lung block weight was recorded. At the end of reperfusion, the left lung was weighed and packaged kept at 70oC for 48h to obtain the wet-to-dry weight ratio. Lung tissue samples were processed for histology, electron microscopy and TUNEL. Statistical analysis included a comparison of the solutions and ischemic times, using ANOVA and Kruskal-Wallis. The significance level was set at 5%. RESULTS: The comparison between the compliance of lungs preserved with Celsior® and Perfadex® in ischemic times of 6 and 12 hours was not statistically significant (p=0.161 and p=0.316, respectively). The lungs subjected to 6 hours of ischemia showed higher lung compliance compared to 12 hours (p=0.02 Perfadex®; Celsior® p=0.019; saline p=0.016). The pulmonary artery pressure values were similar between the three solutions in two stages of ischemia and comparing the times of 6 and 12 hours, regardless of the solution. The Relative Oxygenation Capacity showed no significant difference between the three solutions tested, regardless of the ischemic time. The comparison between the two ischemic times showed that oxygenation capacity was significantly worse in lungs preserved with saline for 12 hours (p=0.001). The wet-to-dry weight ratio showed no statistically significant difference between the three solutions in both ischemic times. However, when ischemic times were compared, Perfadex® showed greater wet-to-dry weight ratio in lungs submitted to 12 hours of ischemia (p=0.001). Light microscopy showed that lungs preserved with saline had more edema than the others, regardless of the ischemic time. Assessment of apoptosis by the TUNEL assay showed no statistically significant difference in the comparison between the groups. CONCLUSIONS: The lungs preserved with Celsior® and Perfadex® performed evenly in regards to gas exchange, hemodynamics and ventilatory mechanics. The lungs preserved with Perfadex® for 12 hours were more edematous. Histopathology findings did not differ between the groups
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Cayer, Christian. ""In vivo" Behavorial Characterization of Anxiolytic Botanicals." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20473.
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This thesis studied three plants traditionally used for treating a variety of anxiety related conditions. The three species were Roseroot, Rhodiola rosea from Nunavik, Cordonsillo, Piper amalago from Belize and “Sin Susto”, Souroubea sympetala from Costa Rica. The main objective of this research project was to investigate effects on behavior of these traditionally used native plants. It was found that the crude ethanol extracts derived from these plants administered intragastrically had measurable anxiolytic effects in male Sprague Dawley rats. Rats treated with extracts of these plants were then tested in several behavioral paradigms: elevated plus maze (EPM), social interaction (SI), conditioned emotional response (CER) and fear potentiated startle FPS. “Sin susto” produced significant anti-anxiety effects in several paradigms. Its active principle, betulinic acid, was significantly active in the EPM and FPS at a dose of 0.5mg/kg. Cordonsillo had strong activity in the SI paradigm and Roseroot in the CER paradigm. The results suggest that traditional use is based on pharmacological activity of the plants.
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Emmett, C. "Astroglial phenotype in vivo and in vitro." Thesis, University College London (University of London), 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380695.
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Ameho, Clement Kojo. "The effect of quercetin as an antioxidant in vivo in rats /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2004.
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Thesis (Ph.D.)--Tufts University, 2004.Adviser: Jeffrey Blumberg. Submitted to the School of Nutrition Science and Policy. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Lund, Jacobsen Bodil B. "In vivo investigations of genetically modified microorganisms using germ-free rats /." Roskilde : Roskilde universitet, Department of Life Sciences and Chemistry, 1996. http://hdl.handle.net/1800/460.
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Hirose, Fumitaka. "In vivo evaluation of retinal injury after transient ischemia in hypertensive rats." Kyoto University, 2006. http://hdl.handle.net/2433/143861.
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Öhrvik, Veronica. "Folate bioavailability in vitro experiments and human trials /." Uppsala : Dept. of Food Science, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200963.pdf.
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Phillipson, Mia. "Acid transport through gastric mucus : A study in vivo in rats and mice." Doctoral thesis, Uppsala University, Department of Medical Cell Biology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3368.
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The gastric mucosa is frequently exposed to endogenously secreted hydrochloric acid of high acidity. Gastric mucosal defense mechanisms are arranged at different levels of the gastric mucosa and must work in unison to maintain its integrity.
In this thesis, several mechanisms underlying gastric mucosal resistance to strong acid were investigated in anesthetized rats and mice. The main findings were as follows:
Only when acid secretion occurred did the pH gradient in the mucus gel withstand back-diffusion of luminal acid (100 mM or 155 mM HCl), and keep the juxtamucosal pH (pHjm) neutral. Thus, when no acid secretion occurred and the luminal pH was 0.8-1, the pH gradient was destroyed.
Bicarbonate ions, produced concomitant with hydrogen ions in the parietal cells during acid secretion and blood-borne to the surface epithelium, were carried transepithelially through a DIDS-sensitive transport.
Prostaglandin-dependent bicarbonate secretion seemed to be less important in maintaining a neutral pHjm.
Removal of the loosely adherent mucus layer did not influence the maintenance of the pHjm. Hence, only the firmly adherent mucus gel layer, approximately 80µm thick, seemed to be important for the pHjm.
Staining of the mucus gel with a pH-sensitive dye revealed that secreted acid penetrated the mucus gel from the crypt openings toward the gastric lumen only in restricted paths (channels). One crypt opening was attached to one channel, and the channel was irreversibly formed during acid secretion.
Gastric mucosal blood flow increased on application of strong luminal acid (155 mM HCl). This acid-induced hyperemia involved the inducible but not the neural isoform of nitric oxide synthase. These results suggest a novel role for iNOS in gastric mucosal protection and indicate that iNOS is constitutively expressed in the gastric mucosa.
It is concluded that a pH gradient in the gastric mucus gel can be maintained during ongoing acid secretion, since the acid penetrates the mucus only in restricted channels and bicarbonate is carried from the blood to the lumen via a DIDS-sensitive transporter.
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Di, Ciano Patricia. "Changes in in vivo dopamine efflux associated with drug-seeking behaviour by rats." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0031/NQ38877.pdf.
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Wilson, Lynn Allison 1953. "The effects of early experience on cognitive functioning in the rat." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277046.
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Forty-eight rat pups were handled and isolated from postnatal days 3 through 13 in order to determine whether this manipulation would alter the postnatal development of the hippocampus. Half of these animals were then reared in enriched environments from weaning until maturity to determine whether enrichment would ameliorate the expected deficits in learning ability. Beginning at 90 days of age, all animals were tested on a T-maze, rotating bar and both place and cued versions of a water maze task. The study failed to find gross deficits in learning as a result of the handling/isolation procedure, although emotional differences between groups was evident, as were sex differences. Apparently more questions have been raised than answered by this study, and possible directions for future research are discussed.
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Chen, Guoyan. "Dielectric characterizations, ex vivo experiments and multiphysics simulations of microwave hyperthermia of biological tissues." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066289/document.
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La recherche et développement de dispositifs médicaux avec diverses applications en diagnostiques et en thérapie ont été réalisés. Actuellement, tous les systèmes micro-ondes disponibles d'hyperthermie proposent uniquement des traitements avec une puissance élevée de micro-ondes. Dans cette thèse, un nouveau système d'hyperthermie micro-ondes est étudié pour le bénéfice des fonctions de diagnostic et de thérapie. L'utilisation d'un applicateur avec un niveau très faible et inoffensif de puissance micro-ondes permet de faire le premier diagnostic. Le traitement thérapeutique thermique sera effectué en utilisant le même applicateur avec une puissance micro-ondes élevée et adaptée sur la partie pathologique. Des caractérisations micro-ondes large bande de cinq tissus biologiques différents ont été effectuées à différentes températures avec une méthode de sonde coaxiale ouverte et le modèle de ligne virtuelle. Les expérimentations ex vivo d'hyperthermie micro-ondes avec des puissances de quelques watts à 2,45GHz ont été réalisées sur ces tissus d'épaisseurs variées. L'évolution de la température des tissus a été mesurée en utilisant un capteur infrarouge. Les simulations électromagnétiques et thermiques pour les expérimentations ex vivo d'hyperthermie micro-ondes ont été effectuées en utilisant COMSOL Multiphysics avec la méthode des éléments finis et la symétrie axiale 2D en considérant les tissus variés de différentes épaisseurs et puissances micro-onde incidente. Les simulations du modèle correspondent bien aux mesures. Cette recherche illustre la possibilité d'avoir un câble coaxial souple et adapté à la fois au diagnostic et au traitement pour une thérapie mini invasiveResearch and development of medical devices with various diagnostic and therapeutic applications have been carried out in different countries because of the great advances in electronic and electromagnetic devices during recent decades. However, at present, all of available existing microwave hyperthermia system can just offer treatment, by using high microwave power. In this thesis, a new microwave hyperemia system is researched which could have both diagnostic and therapeutic functions. One single applicator is used to measure dielectric properties of tissue with a very low harmless microwave power for diagnosis first. Then thermal therapeutic treatment will be carried out by using the same applicator with higher and adapted microwave power. Microwave broad band characterization of five different biological tissues at different temperatures with an open–ended coaxial probe method and the virtual line model has been carried out. Ex vivo microwave hyperthermia experiments using microwave power of a few Watts at 2.45GHz have been carried out on five tissues of various thicknesses. Temperature evolution of the biological tissues has been measured by using an infra-red senor. Electromagnetic and thermal simulations for ex vivo microwave hyperthermia experiment have also been achieved by using COMSOL Multiphysics software with 2D axisymmetrical finite–element method and considering different tissues of various thicknesses and incident microwave powers. Simulation results correlate well with the experimental ones. This research, illustrates the possibility to have a flexible and feasible coaxial cable for both diagnosis and treatment for a minimally invasive therapy
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Chirrey, Linda Alexandra. "A study of the in vivo metabolism of mitomycin C in tumour tissue." Thesis, University of Strathclyde, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319280.
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Bertolín, Gálvez Joan. "Terapia génica in vivo para la mucopolisacaridosis tipo iva: estudio de la eficacia en una nueva rata modelo de la enfermedad." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/669376.
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La Mucopolisacaridosis tipo IVA (MPS IVA) es una enfermedad de depósito lisosomal causada por la deficiencia de la enzima N-acetilgalactosamina 6-sulfatasa (GALNS). La ausencia de esta enzima conduce a la acumulación patológica de los glicosaminoglicanos (GAG) Queratán Sulfato (KS) y Condroitín-6-Sulfato.
Actualmente, no existe un modelo animal que mimetice todos los signos clínicos de la MPS IVA humana. Por ello, el objetivo inicial de la presente tesis doctoral fue generar una nueva rata modelo de la MPS IVA introduciendo la mutación missense más frecuente en humanos (c.1156C>T) mediante la tecnología CRISPR/Cas9. Posteriormente, se caracterizó este modelo, el cuál desarrolló los signos típicos de la enfermedad, como alteraciones en el tamaño corporal, pérdida temprana del cartílago articular, hipertrofia de condrocitos, hipoplasia de esmalte, acumulación de GAGs en diferentes órganos y tejidos y una reducción de la esperanza de vida.
Dado que no existe un tratamiento capaz de revertir todas las alteraciones que sufren los pacientes de Morquio A, el siguiente objetivo de la presente tesis doctoral fue el desarrollo de una nueva aproximación de terapia génica para el tratamiento de la MPS IVA. Para ello, se estudió la biodistribución del vector AAV9 tras una administración intravenosa (IV). Los resultados demostraron una alta eficiencia de transducción en huesos, cartílago articular, dientes, órganos y sistema nervioso central (SNC). Por ello, se desarrolló una estrategia de terapia génica basada en la administración IV del vector AAV9-Galns. Dicha administración permitió el incremento de actividad GALNS en suero y en múltiples órganos. El tratamiento permitió una recuperación del tamaño corporal y mejoró la tasa de supervivencia. También se detectó una mejora en el cartílago de crecimiento, con una normalización de los niveles de KS, que se tradujo en una normalización de la composición y estructura ósea. El tratamiento con AAV9-Galns llevó a una mejoría de las alteraciones en las articulaciones de las ratas MPS IVA, que resultaron en una normalización de la fuerza de agarre. El tratamiento también fue capaz de recuperar el esmalte y mejorar el fenotipo dentario de las ratas MPS IVA. A nivel periférico, se normalizaron las células vacuoladas del hígado, el sistema respiratorio y el corazón. En cuanto al SNC, se observó una normalización de los niveles de KS y de las alteraciones observadas en ratas MPS IVA no tratadas.
En conjunto, estos resultados mostraron que el nuevo modelo de rata MPS IVA era capaz de desarrollar los principales signos clínicos de la enfermedad de Morquio A y que una sola administración IV del vector AAV9-Galns era capaz de mejorar e incluso corregir las alteraciones observadas en dicho modelo. Por ello, la estrategia de terapia génica descrita en este trabajo podría constituir la base preclínica para la translación hacia la clínica de la administración de AAV9-Galns en pacientes de Morquio AMucopolysaccharidosis type IVA (MPS IVA) is a lysosomal storage disease caused by the deficiency of the enzyme N-acetylgalactosamine-6-sulfatase (GALNS). The absence of this enzyme leads to the pathological accumulation of glycosaminoglycans (GAG) Keratan Sulfate (KS) and Chondroitin-6-Sulfate. To date, there is no animal model that mimics all the clinical signs of human MPS IVA. Therefore, the main objective of this doctoral thesis was to generate a new MPS IVA rat model introducing the most frequent missense mutation in humans (c.1156C>T) using the CRISPR/Cas9 technology. Then, this model was characterized, which developed the typical signs of the disease, such as alterations in body size, early loss of articular cartilage, chondrocyte hypertrophy, enamel hypoplasia, accumulation of GAGs in multiple organs and a reduction of the survival rate. As there is no treatment capable of reversing all the skeletal alterations of Morquio A patients, the next objective of this doctoral thesis was the development of a new gene therapy approach for the treatment of MPS IVA. To this aim, the biodistribution of an AAV9 vector was studied after intravenous (IV) administration. The results demonstrated a high efficiency of transduction in bones, articular cartilage, teeth, peripheral organs and central nervous system (CNS). Therefore, a gene therapy strategy was developed based on the IV administration of the AAV9-Galns vector. The administration of the therapeutic vector allowed the increase of GALNS activity in serum and in multiple organs. The treatment allowed a recovery of body size and improved the survival rate. An amelioration of growth cartilage was also detected, with a normalization of KS levels, which resulted in a normalization of bone composition and structure. Treatment with AAV9-Galns led to an improvement of joint alterations of MPS IVA rats, which resulted in a normalization of grip strength. The treatment was also able to recover the enamel and improve the dental phenotype of MPS IVA rats. At the peripheral level, the vacuolated cells of the liver, respiratory system and heart were normalized. Regarding the CNS, a normalization of the KS levels and the alterations observed in not treated MPS IVA rats was also observed. Altogether, these results showed that the new MPS IVA rat model presented the main clinical signs of Morquio A. Therefore, the therapeutic efficacy of an IV administration of the AAV9-Galns vector on bone tissue, peripheral organs and the SNC was evaluated in this model. The gene therapy approach described in this work could constitute the preclinical basis for the translation to the clinic of the IV administration of AAV9-Galns in patients of Morquio A.
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Gagne, Christine Mona. "The effects of exercise on iron metabolism in adult female rats." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54291.
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The effects of exercise training and iron intake on iron metabolism in adult female rats were investigated. Adult female Sprague-Dawley rats were assigned to either an exercise (E) or sedentary (S) group and fed either a diet containing 9 ppm (9) of dietary iron (low iron level), or 40 ppm (40) of iron (a level slightly above the National Research Council recommendations). The exercise animals were subjected to a program of swimming, 5 days/week, over a 6- week period.
Total food intake and final body weight were similar between the E and S groups. In both 40-E and 9-E animals, concentration of serum iron was significantly (P<0.05) lower while total iron binding capacity was significantly elevated, when compared to sedentary counterparts. Saturation of transferrin was significantly reduced in the 9-E group. Liver and spleen weights did not differ but significant increases in cardiac weights were noted in both E groups. Gastrocnemius muscle weights were similar in both E groups and 9-S, but significantly lower in the 40-S group. In organ tissues, liver iron concentration was significantly reduced in the 9-E animals, while spleen iron level was highest in the 40-E group. Cardiac iron concentration was significantly reduced in both E and low iron diet groups while levels of iron in gastrocnemius muscle did not differ among experimental groups. In both groups of exercised rats, bone marrow iron was significantly lower when compared to sedentary animals. In response to exercise training, an increase in skeletal muscle citrate synthase activity was observed in both E groups.
This study suggests that exercise affects various parameters of iron metabolism. Regardless of iron intake, physical training appeared to alter distribution of iron stores, that may be associated with alterations of hematological iron transport and iron-containing proteins. The Combination of a low iron intake and intense exercise training appeared to enhance early characteristics of a latent iron deficiency.Ph. D.
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Shastri, Vineet. "Development of an apparatus to quantify the volitional muscle performance of rat plantar flexors in vivo." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1958.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains vii, 56 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 48-50).
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Fahy, Patricia A. "Ovarian inhibin : in vitro studies using bovine granulosa cells and in vivo studies in rats." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309518.
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Pitcher, Toni Leigh, and n/a. "In vivo electrophysiology of striatal spiny projection neurons in the spontaneously hypertensive rat (SHR)." University of Otago. Department of Anatomy & Structural Biology, 2007. http://adt.otago.ac.nz./public/adt-NZDU20070321.114819.
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The aim of this thesis was to investigate neuronal cellular mechanisms that may underlie the behavioural characteristics of the spontaneously hypertensive rat strain (SHR). The SHR was developed by selective breeding for elevated blood pressure and is also described as having increased levels of locomotor behaviour compared to its normotensive control strain, the Wistar-Kyoto. This hyperactivity and other behaviours, including altered sensitivity to reinforcement, have been used to model aspects of behaviour displayed in attention deficit hyperactivity disorder. In vivo intracellular recording of striatal spiny projection neuron activity in urethaneanaesthetised animals from three genetically related strains: the SHR, Wistar-Kyoto and standard Wistar, was employed to measure basic cellular properties and cellular mechanisms of reward-related learning. This population of neurons was chosen because alterations in their activity can influence behaviour and they are known to show cellular changes (synaptic plasticity) that are associated with learning.
Cellular properties were measured in 71 neurons. Comparison between strains revealed a significant difference in action potential amplitude and duration between the SHR and Wistar-Kyoto strains. Interestingly, when measured at a later time, in a different sample of rats, the SUR action potential amplitude and duration were significantly different from the earlier sample. A change in the membrane potential repolarisation rate following action potential firing also occurred over this time. Twenty-nine of these neurons were also used in a study investigating the neuronal responses to a low dose of amphetamine (0.5 mg/kg). Changes were observed in some cellular properties following intraperitoneal administration of amphetamine.
Synaptic plasticity at the corticostriatal synapses is sensitive to the timing of dopamine release in relation to cortical input. In anaesthetised preparations the spiny projection neuron membrane potential fluctuates between hyperpolarised (DOWN) and depolarised (UP) states, which reflect the level of cortical input. During the present study the responses of nine neurons to the induction of cortical spreading depression were observed to investigate the suitability of this method for use during synaptic plasticity experiments. Spiny projection neurons showed unpredictable responses to cortical spreading depression, therefore this method was not used further. Corticostriatal synaptic plasticity was induced in sixteen spiny projection neurons from two strains: SHR and Wistar. High frequency stimulation of the dopamine neurons in the substantia nigra, during the DOWN-state, did not induce any significant changes in corticostriatal synaptic efficacy. This was also true when high frequency stimulation of dopamine neurons was applied during the UP-state in neurons from the SHR strain.
This thesis represents the first in vivo intracellular study of neuronal physiology in the SHR and Wistar-Kyoto rat strains. Results revealed action potential differences between these two behaviourally distinct rat strains. Synaptic mechanisms thought to underlie reward-related learning were not different between the SHR and Wistar strains, although the observed levels of plasticity were inconsistent with previous literature.
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陳世安 and Sai-on Chan. "In vivo and in vitro studies on the regulation of C-KI-RAS expression in liver." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B30251813.
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Silva, Paulo Eduardo da. "Efeitos do protocolo de estressores em ratos submetidos a um regime contínuo de privação de água." Pontifícia Universidade Católica de São Paulo, 2015. https://tede2.pucsp.br/handle/handle/16753.
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The Chronic Mild Stress (CMS) has been described in the literature as an experimental model of anhedonia, central symptom of depression in humans. The anhedonia has been studied in this model looking for a decrease of water with sucrose consumption in rats. This result is usually observed after the animal had been subjected to a set of stressful stimuli in a moderated and chronical way, for six weeks in average. The present study aimed to investigate the effects of the Stressors Protocol in rats subjected to a continuous water deprivation regimen. Eleven male rats of Wistar lineage were studie,. All the rats were subjected to a water deprivation schedule until reaching 85% of their ad lib weights, and they were maintained at these weights for the whole study. Thirteen water and water with sucrose consumption tests were used for all the subjects, while S7 was exposed only to the liquids consumption tests. S3 subject was submitted only to the Stressors Protocol. S5 was exposed to the same conditions of S3, except that the Stressors Protocol involved only the grouping stressor. For the other eight subjects, first they had the bar press response to the two bars modeled, using water as reinforcement. Then these eight animals were subjected to a Conc VI 5 sec VI 5 sec reinforcement, each bar being associated to water or water with sucrose reinforcements (one for each bar). After four weeks in this reinforcement schedule these animals were subjected to the Stressors Protocol for six consecutive and uninterrupted weeks in their living cages. During the protocol, four subjects (S2, S6, S8 and S10) also had their bar press responses reinforced in a Conc VI 5 sec VI 5 sec schedule (group before, during and after). The other four rats (S1, S4, S9 and S11- group before and after) were not submitted to operant sessions as long as the Stressors Protocol was available. At the end of the phase when the Stressors Protocol was available, these eight subjects were again subjected to the base line condition. The main results were: (a) a weight stability for the animals subjected to the protocol, (b) a high alternation of water and water with sucrose consumption in the tests for the only subject submitted to the tests and to the protocol, not demonstrating anhedonia, (c) a reduction in the animal s food consumption and an increase of water consumption in the living cage during the protocol for seven subjects, (d) the stressors protocol was not followed by a modification of the distribution of water and water with sucrose reinforced responses by Conc VI 5sVI5s, neither during the protocol, nor after its cessation, and (e) it seems that the reinforcement value of the liquids alternated for some subjects over major of the sessions. The role of continuous water deprivation and the measures used as anhedonia indicators are discussed
O Chronic Mild Stress (CMS) tem sido descrito na literatura como um modelo experimental de anedonia, sintoma central na depressão em humanos. A anedonia tem sido estudada dentro desse modelo a partir do decréscimo no consumo de água com sacarose em ratos. Este resultado é geralmente observado após o animal ser submetido a um conjunto de estímulos estressores de forma moderada e crônica, durante seis semanas em média, O presente estudo teve como objetivo investigar os efeitos do Protocolo de Estressores em ratos submetidos a um regime contínuo de privação de água. Foram empregados 11 ratos machos, da linhagem Wistar. Todos os sujeitos foram submetidos a um esquema de privação de água até atingir 85% dos seus pesos ad lib. e foram mantidos nesses pesos durante todo o estudo. Foram empregados 13 testes de consumo de água e de água com sacarose, sendo que o Sujeito S7 só passou pelos testes de consumo dos líquidos. O Sujeito S3 foi submetido ao Protocolo de Estressores. O sujeito S5 passou pelas mesmas condições que o S3, exceto que o Protocolo de Estressores envolveu apenas o estressor agrupamento. Para os outros 8 sujeitos, primeiramente foram modeladas as respostas de pressão às duas barras, usando água como reforçador. Depois, esses 8 animais foram submetidos a um esquema Conc VI 5 seg VI 5 seg associado aos reforços água e água com sacarose (um para cada barra). Após quatro semanas nesse esquema de reforçamento esses animais foram submetidos ao Protocolo de Estressores por seis semanas consecutivas e ininterruptas nas suas gaiolas-viveiro. Durante o Protocolo, 4 sujeitos (S2, S6, S8, S10) também tiveram suas respostas de pressão à barra reforçadas num esquema Conc VI 5 seg VI 5 seg (grupo antes, durante e depois) e os outros 4 (S1, S4, S9, S11) não (grupo antes e depois). Ao término do Protocolo de estressores, esses 8 sujeitos foram submetidos novamente à condição de linha de base. Os principais resultados encontrados foram: (a) estabilidade nos pesos dos animais submetidos ao protocolo, (b) maior oscilação em relação ao consumo de água e de água com sacarose para o sujeito submetido apenas aos testes e ao protocolo, não demonstrando anedonia, (c) redução no consumo de ração e aumento no consumo de água na gaiola-viveiro durante o protocolo (d) o protocolo de estressores não foi acompanhada por uma alteração na distribuição de respostas reforçadas com água e água com sacarose, nem durante e nem após a suspensão do mesmo, e (e) o valor reforçador dos líquidos parece ter se alternado para alguns sujeitos ao longo da maioria das sessões. Discute-se o papel da privação contínua de água e as medidas utilizadas como indicativas a de anedonia
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Persson, Kirstin Gracia. "In vivo effects of crinum macowanii on the rat cardiovascular system." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_4721_1222073945.
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Crinum macowanii (C. macowanii) (Amaryllidacea) as authenticated by Mr. F. Weitz at the Herbarium, University of the Western cape, is widely used a traditional remedy and is thought to have therapeutic value (Fennell and van Staden 2001). The objective of this study was to determine the cardiovascular effects of the crude aqueous extract of Crinum macowanii on the rat and to determine the effect of pre-treatment drugs on Crinum macowanii in in vivo, anaesthetized normotensive, male Wistar rats (200-250 g.).
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Cournil-Henrionnet, Christel. "Potentialités chondroprotectrices d'Hsp70 vis à vis des phénomènes apoptotiques : Etudes in vitro et in vivo chez le rat." Nancy 1, 2003. http://www.theses.fr/2003NAN12504.
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L'arthrose se caractérise par une hypocellularité du cartilage, doublée d'anomalies de la matrice extracellulaire. La mort du chondrocyte concourt sans doute à la pathogénie de l'arthrose puisque plusieurs travaux récents révèlent qu'un excès d'apoptose est observé dans les chondrocytes, provenant de cartilage arthrosique. Nous avons développé au laboratoire un modèle expérimental d'arthrose chez le rat par injection intra-articulaire (ia) de mono-iodoacétate (MIA) dans le genou. Une première partie de ce travail de thèse a donc été d'étudier la chondrotoxicité du MIA sur des cultures de chondrocytes de rat et de confirmer la participation des phénomènes apoptotiques aussi bien in vitro qu'in vivo, dans le modèle d'arthrose induit par le MIA chez le rat. Après avoir identifié certains acteurs de ce processus de mort cellulaire (Bax, Bcl-2, caspases, importance de la mitochondrie ), nous avons dans un second temps essayé de moduler la sévérité des atteintes articulaires. Pour ce faire, nous nous sommes intéressés aux capacités protectrices de la protéine Hsp70 dont les effets bénéfiques tant vis-à-vis de l'apoptose que de la nécrose, sont déjà démontrés dans d'autres pathologies. Les résultats obtenus in vitro démontrent de réelles propriétés chondroprotectrices de cette protéine, vis-à-vis de la toxicité du MIA, que ce soit grâce à une surexpression par transfert de gène, ou par induction au moyen d'un inhibiteur du protéasome, le MG132. In vivo, un pré-traitement par le MG 132 a permis de diminuer significativement la sévérité des lésions cartilagineuses provoquées par l'injection ia de MIA, cette protection passant par une surexpression des protéines de stress. Afin de valider les propriétés bénéfiques d'Hsp70, nous avons développé une méthode originale de vectorisation non virale de transgènes dans le tissu articulaire. Cette technique repose sur l'utilisation d'impulsions électriques pour délivrer une information génétique dans un tissu cible. Les résultats préliminaires obtenus lors de notre travail ont démontré l'intérêt d'une telle approche dans le cartilage articulaire, tissu complexe et difficile à transfecter efficacement de part la présence d'une matrice extracellulaire dense. Après avoir validé cette méthode, nous avons pu démontré que la surexpression d'Hsp70 in vivo par cette technique d'électroporation permet de protéger efficacement le cartilage articulaire rotulien de la toxicité du MIA. Par ailleurs, la mise en évidence des propriétés protectrices d'Hsp70 nous a permis de comprendre et d'expliquer en partie l'effet bénéfique d'un exercice physique modéré sur le développement de lésions articulaires, lors d'un modèle expérimental d'arthrose par section du ligament croisé antérieur. Cet effort physique modéré entraîne une surexpression du taux d'expression des protéines de stress dans le tissu articulaire. Cette surexpression semble être corrélée avec la protection observée lors d'un exercice modéré et permet, dans une certaine mesure de s'opposer à l'aggravation de la dégradation contingente de la dysfonction articulaire lors de ce modèle.
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Petekkaya, Ali Tolga. "In Vivo Indenter Experiments On Soft Biological Tissues For Identification Of Material Models And Corresponding Parameters." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610071/index.pdf.
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Soft biological tissues, being live and due to their physiological structures,
display considerably complex mechanical behaviors. For a better understanding
and use in various applications, first study to be carried out is the tests made
particularly as in vivo. An indenter test device developed for this purpose in the
METU, Department of Mechanical Engineering, Biomechanics Laboratory is
operational.
In this study, in order to carry out precise and dependable tests, initially, various
tests and improvements were conducted on the device and the software
controlling the device. At the end of this study, displacement and load
measurement accuracies and precisions were improved. Better algorithms for
filtering the noisy data were prepared. Some test protocols within the software
were improved and new protocols were annexed. To be able to conduct more
dependable tests a new connection system was attached to the device. In order to
study the anisotropic behavior of soft tissues ellipsoid tips were designed and
produced.
In the second phase of the study, tests on medial forearm were carried out. In
these tests, hysteresis, relaxation and creep behaviors displaying the viscoelastic
v
properties of the soft biological tissues were observed. In addition to viscoelastic
behaviors, preconditioning (Mullin’
s) effect and anisotropic response were examined. By using the results of the relaxation and creep tests, parameters of the Prony series capable of modelling these data were determined. With this study, some important conclusions regarding the soft biological tissues were drawn and thus the behaviors of the soft biological tissues were better understood. Besides, the difficulties inherent to in-vivo tests were recognized and actions to reduce these difficulties were explained. Finally, clean experimental data, to be used in the computer simulations, were obtained.
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Ström, Jakob, Edvin Ingberg, Annette Theodorsson, and Elvar Theodorsson. "Method parameters’ impact on mortality and variability in rat stroke experiments : a meta-analysis." Linköpings universitet, Klinisk kemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93981.
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Background Even though more than 600 stroke treatments have been shown effective in preclinical studies, clinically proven treatment alternatives for cerebral infarction remain scarce. Amongst the reasons for the discrepancy may be methodological shortcomings, such as high mortality and outcome variability, in the preclinical studies. A common approach in animal stroke experiments is that A) focal cerebral ischemia is inflicted, B) some type of treatment is administered and C) the infarct sizes are assessed. However, within this paradigm, the researcher has to make numerous methodological decisions, including choosing rat strain and type of surgical procedure. Even though a few studies have attempted to address the questions experimentally, a lack of consensus regarding the optimal methodology remains. Methods We therefore meta-analyzed data from 502 control groups described in 346 articles to find out how rat strain, procedure for causing focal cerebral ischemia and the type of filament coating affected mortality and infarct size variability. Results The Wistar strain and intraluminal filament procedure using a silicone coated filament was found optimal in lowering infarct size variability. The direct and endothelin methods rendered lower mortality rate, whereas the embolus method increased it compared to the filament method. Conclusions The current article provides means for researchers to adjust their middle cerebral artery occlusion (MCAo) protocols to minimize infarct size variability and mortality.Funding Agencies|County Council of Ostergotland, Sweden||
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Lee, Chun-kei, and 李鎮基. "Development of an in vivo animal model for testing of endodontic medicaments on pulp tissue." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31954182.
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Lee, Chun-kei. "Development of an in vivo animal model for testing of endodontic medicaments on pulp tissue." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B23300462.
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Graves, S., C. Lewis, H. Valdovinos, B. Bednarz, W. Cai, T. Barnhart, and R. Nickles. "In vivo cell tracking with 52Mn PET: Targetry, Separation, and Applications." Helmholtz-Zentrum Dresden - Rossendorf, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-166432.
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Introduction
52Mn (t½ =5.59 d, β+ = 29.6%, Eβmax = 0.58 MeV) has great potential as a long lived PET isotope for use in cell tracking studies, observation of immunologic response to disease states, or as an alternative to manganese-based MRI contrast agents. Its favorable max positron energy leads to superb imaging resolution, comparable to that of 18F.[1]
Manganese is naturally taken up by cells via a multitude of pathways including the divalent metal transporter (DMT1), ZIP8, transferrin receptors (TfR), store-operated Ca2+ channels (SOC-Ca2+), and ionotropic glutamate receptor Ca2+ channels (GluR).[2] These natural transport mechanisms make 52Mn an attractive isotope for applications necessitating non-perturbative cell uptake. In particular, cell tracking is critical to the development and translation of stem cell therapies in regenerative medicine. Alternative-ly, 52Mn could be used in immunotherapy techniques such as adoptive cellular therapy (ACT) to evaluate the ability of external immune cells to reach their intended target.
Material and Methods
52Mn was produced by natCr(p,x)52Mn using 16 MeV protons. The average thick target production yield was 0.23 mCi/µA-h with less than 0.25% co-production of 54Mn. Small amounts of 51Cr were observed in the target, but were absent from the radiochemically separated product.
Target construction consisted of a water jet cooled chromium disc (3/4” diameter, 0.4” thick). Targets were purchased from Kamis Inc, and are 99.95% pure. Targets withstood beam currents of 30 µA with no visible aberration.
Chromium targets were etched by concentrated HCl following bombardment. Mn2+ ions were extracted from 9M HCl to 0.8M trioctylamine in cyclohexane leaving the bulk chromium in the aqueous phase. After isolating the organic phase, 0.001M NH4OH was used to back-extract the Mn2+ ions to aqueous phase. This purification cycle was conducted a total of three times for each 52Mn production.
Results and Conclusion
For a starting bulk chromium mass of 456 ± 1 mg, a post-separation chromium mass of 5.35 ± 0.04 ng was measured by microwave plasma atomic emission spectrometry (MP-AES). This mass reduction corresponds to an average separation factor of 440 for a single purification cycle. Each purification cycle had a 52Mn recovery efficiency of 73 ± 7 % (n = 6), resulting in an overall separation efficiency of approximately 35 %. These efficiencies and separation factors agree reasonably well with the work conducted by Lahiri et. al.[3] Prior to use, the product was passed through a C-18 Sep-Pak to remove any residual organic phase.
After four target irradiations and etchings, some pitting became noticeable on the target face. These have not yet compromised the o-ring seal with the target deplater, but it is possible that target replacement after every 6–9 52Mn productions will be necessary moving forward.
Following the successful separation of 52Mn from chromium, in vitro experiments were conducted to demonstrate the uptake of 52Mn by human stem cells and mouse tumor cells. A linear uptake response was observed as a function of the amount of activity exposed to the cells for both cell models. These experiments have shown great promise for 52Mn as a long-lived PET isotope in cell tracking studies. Details will be presented.
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Jeannin, Jean-François. "Modifications par les endotoxines de l'effet des macrophages sur les cellules cancéreuses intestinales de rat : Etude in vitro et in vivo." Dijon, 1985. http://www.theses.fr/1985DIJOS049.
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Zhou, Xin. "In silico investigations into human ventricular pro-arrhythmic mechanisms combined with in vivo and in vitro experiments." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:b36acc5e-d6d6-4369-b0a4-3a868b5fcf0f.
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Sudden cardiac death (SCD) is one of the largest causes of natural mortality throughout the world. SCD can be triggered through ventricular arrhythmias due to many pathological conditions, including coronary artery diseases, arrhythmogenic cardiomyopathies and genetic mutations of ionic channel proteins. Although considerable research has been conducted to study proarrhythmic mechanisms, most studies were in animal models due to ethical limitations in human cardiac research. Therefore, more research is needed to investigate the proarrhythmic ionic mechanisms in human. In this thesis, we use biophysically-detailed models of human cardiac electrophysiology to explore the ionic mechanisms underlying several proarrhythmic conditions. A first study is to use traditional modeling approach to explore the effect of ionic remodelling in human epicardial border zone (EBZ) cells post myocardial infarction by introducing the analogous remodelling observed in canine. Sensitivity analysis of the human EBZ models leads to our interest in developing new techniques to include general variability into human cardiac electrophysiology research. Therefore, a novel methodology to include the effect of in vivo cardiac variability in human electrophysiology is developed in this study by constructing a population of models calibrated using in vivo human data. The experimentally-calibrated population of human ventricular cell models is then applied to investigate the proarrhythmic ionic mechanisms underlying cardiac alternans, and to test the effects of potential anti-arrhythmic drug therapies on alternans. We then explore the interaction between cardiac variability and a mutation of slow delayed rectifier potassium channel. Our simulation results reveal the complex interactions between different ionic components in the integrated electrophysiological system, highlighting the importance of cardiac variability in the development of proarrhythmic conditions.
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Missy, Pascale Burnel Daniel. "Recherche de nouveaux chélateurs du manganèse, en vue de la détoxication de l'organisme Etude in vivo et in vitro chez le rat /." [S.l.] : [s.n.], 2001. ftp://ftp.scd.univ-metz.fr/pub/Theses/2001/Missy.Pascale.SMZ0123.pdf.
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Lee, Jennifer S. C. "The in vivo effects of BaP:DMBA and resveratrol on the bone and the ovary of young rats." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63100.pdf.
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Cherkaoui-Malki, Mustapha. "Contribution à l'étude du mécanisme d'action des proliférateurs de péroxysomes au niveau post-traductionnel et post-transcriptionnel dans les cellules hépatiques de rats traités in vivo." Besançon, 1991. http://www.theses.fr/1991BESA2047.
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Le but de ce travail est de caracteriser certains aspects de la proliferation des peroxysomes au niveau post-transcriptionnel et post-traductionnel dans les cellules hepatiques de rats traites par des proliferateurs de peroxysomes. Un protocole de la purification des peroxysomes de foie de rat a ete mis au point grace a l'ultracentrifugation de la fraction l dans un gradient discontinu de metrizamide. La purete de la fraction peroxysomale avoisine les 98% et elle represente 8% des peroxysomes de foie. Ceci nous a permis de caracteriser, en page-sds et par western blot, trois polypeptides membranaires dont les masses moleculaires sont de 7a, 41, et 22 kd. Ces proteines sont induites par les proliferateurs de peroxysomes. Les molecules de type fibrate augmente a la fois la masse de proteines peroxysomales et les activites de l'acyl-coa oxydase et de la catalase. On constate aussi l'activation des genes codant pour la catalase et les enzymes de la beta-oxydation comme le revlele le taux des arnm correspondants. Les images de microscopie montrent clairement une proliferation des peroxysomes. Au cours de ce travail, nous avons essaye de determiner la relation existant entre les proliferateurs de peroxysomes et l'hepatocarcinogenese via l'expression de certains proto-oncogenes. Les resultats que nous avons presentes dans cette etude montrent de facon indeniable qu'il existe une autre voie d'activation des proto-oncogenes, en tous cas pour: c-fos, c-myc, n-myc et c-ha-ras, par une nouvelle classe de carcinogenes, non-mutagenes, que sont les proliferateurs de peroxysomes
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Podwojewski, Florence. "Caractérisation biomécanique globale de la paroi abdominale saine, lésée et réparée : de l’ex vivo à l’in vivo." Thesis, Lyon 1, 2012. http://www.theses.fr/2012LYO10270.
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Les données sur le comportement biomécanique de la paroi abdominale restent limitées. Cette méconnaissance est un facteur limitant pour le développement de modèles numériques de cette région anatomique. L’objectif de cette thèse est d’apporter des données quantitatives sur le comportement biomécanique de la paroi abdominale, en adoptant une approche expérimentale globale allant de l’ex vivo à l’in vivo. Dans un premier temps, un protocole de caractérisation ex vivo est mis au point et validé sur des spécimens porcins, puis appliqué à des échantillons humains. Ce protocole permet de tester une même paroi abdominale sous deux types de sollicitation (pression et contact) dans le domaine élastique. Il permet également d’évaluer l’influence d’une lésion et d’une réparation avec un implant chirurgical, sur la réponse mécanique de la paroi. Des mesures par corrélation d’images 3D réalisées simultanément sur les surfaces internes et externes quantifient les différences de distribution des déformations de la paroi abdominale. Dans un second temps, des examens in vivo sur volontaires permettent de prendre en compte l’activité musculaire. Une raideur locale est ainsi évaluée pour diverses activités physiologiques, raideur qui augmente en fonction du niveau de contraction jusqu’à 6 fois la valeur au repos. En résumé, cette recherche propose une méthodologie pour mieux comprendre le comportement mécanique global de la paroi abdominale. Cette méthodologie peut être déclinée, afin d’étudier l’influence des différents composants de la paroi. Au-delà de cette thèse, ces données contribueront à la construction et la validation d’un modèle numérique de la paroi abdominaleData on the biomechanical behaviour of the abdominal wall are limited. This lack of knowledge is a limiting factor for the development of numerical models of this anatomical area. Therefore, the objective of this thesis is to provide quantitative data on the biomechanical behaviour of the abdominal wall, adopting a global experimental approach ranging from ex vivo to in vivo. As a first step, a protocol for ex vivo characterization is develop and validated on porcine specimens and then applied to human anatomical specimens. This protocol allows testing a same abdominal wall under two loading types (pressure and contact) in the elastic range. It also enables to assess the influence of an incision and of a repair with a surgical implant on the mechanical response. Measurements by 3D digital image correlation performed simultaneously on the internal and external surfaces quantify differences in strain distribution of the abdominal wall. As a second step, in vivo examinations on volunteers enable to take into account muscle activity. A local stiffness is thus assessed for various physiological activities. This stiffness increases with the level of muscle contraction and reaches on average six times the stiffness at rest. In conclusion, this research proposes a methodology to better understand the global mechanical behaviour of the abdominal wall. This methodology can now be used in order to study the influence of the different components of the abdominal wall. Beyond this thesis, these data will contribute to the construction and validation of a numerical model of the abdominal wall
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Broussolle, Emmanuel. "Effet d'un activateur noradénergique, dopaminergique, et cholinergique central, le RU 24722, sur la consommation cérébrale locale de glucose mesurée in vivo chez le rat." Lyon 1, 1985. http://www.theses.fr/1985LYO10279.
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Cunat, Lisiane Burnel Daniel. "BIODISPONIBILITE DE L'ALUMINIUM DANS L'INTESTIN. ETUDES IN VITRO ET IN VIVO CHEZ LE RAT /." [S.l.] : [s.n.], 1999. ftp://ftp.scd.univ-metz.fr/pub/Theses/1999/Cunat.Lisiane.SMZ9931.pdf.
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Merchant, S. J. "Experiments in anaesthetised rats to determine the role of acetylcholine in the release of noradrenaline from the cervical sympathetic nerve." Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381280.
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Santoro, Davide. "Optimisation of indirect detected ¹³C spectroscopy and micro-imaging experiments for in vivo applications in plants." Thesis, University of Nottingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407096.
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Leding, Albin. "Optimized design recommendation for first pharmacokinetic in vivo experiments for new tuberculosis drugs using pharmacometrics modelling and simulation." Thesis, Uppsala universitet, Institutionen för farmaci, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-447311.
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Tuberculosis, the leading cause of death by a single infection disease caused by bacteria, requires long treatments and the bacteria are prone to develop drug resistance. Therefore, new efficient treatment regiments needs developing, which requires new tools for drug development. A major reason for discontinuance of a drug under development is undesired pharmacokinetic properties. Therefore, it is important to have early information of this, preferably the first time the drug is tested in animals. The first in vivo pharmacokinetic experiment is often done in mice and the only information present at this stage are often in vitro values and physicochemical properties. Physiological-based pharmacokinetic modelling can be used to extrapolate from in vitro to in vivo values. From this, the first in vivo pharmacokinetic experiment can be designed, often with the goal of reducing the amount of mice. This goal is one of the three R.s and it is called Reduction. To explore the Reduction of an experiment population pharmacokinetic modelling can be utilized via exploration of the imprecision, bias and probability of an informative experiment to evaluate if a design meets the goal of Reduction. In this report a recommendation of the first in vivo pharmacokinetic experiment is presented. This is based on in vitro values and physicochemical properties that are common in anti-tuberculosis drugs. If the probability of an informative experiment is critical, a terminal sampling of 40 mice is recommended. If imprecision and bias are necessary, zipper sampling of 10 mice is recommended.
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唐國華 and Guohua Tang. "Growth modification of the rat's mandibular condyle by functional appliances: a cellular and molecular study." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31245997.
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Hussenet, Marie-Pierre. "Influence de la monensine sur l'absorption de l'acide oléique "In Vitro" et "In Vivo" chez le rat." Dijon, 1990. http://www.theses.fr/1990DIJOS046.
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L'ionophore monensine est un antibiotique produit par Streptomyces cinnamonensis. Il est utilisé en nutrition animale, soit chez les Ruminants en vue de favoriser le gain de poids, soit chez les Gallinacées comme anticoccidien. Selon la littérature, la monensine modifie la structure et la fonction du complexe golgien et perturbe l'exocytose. La glycosylation des lipoprotéines intestinales (forme de transport des acides gras à longue chaîne), ayant lieu au niveau du complexe golgien, l'action de la monensine, sur l'absorption des acides gras à longue chaîne, est etudiée chez un mammifère monogastrique, le rat. Les experiences sont conduites "In Vitro" et "In Vivo" avec deux doses de monensine (260 et 2600 ug) et deux doses différentes de lipides marqués à l'acide oléique 14C, en conservant les mêmes rapports molaires (ou en masse) monensine/lipides selon le protocole expérimental. "In Vitro", les intestins isolés sont perfusés pendant deux heures par un milieu de perfusion constitué d'une solution saline, additionnée de glucose et de l'émulsion lipidique radioactive étudiée. Les transudats lipidiques, termes de la translocation de l'acide oléique 14C, sont recueillis en fonction du temps. "In Vivo", les animaux porteurs d'une fistule du canal chylifère intestinal principal recoivent l'émulsion lipidique en une seule fois dans la lumière duodénale. La lymphe est recueillie par fractions au cours des six heures suivantes. Que ce soit "In Vitro" ou "In Viv", l'absorption de l'acide oléique n'est pas modifiée significativement par la faible dose en monensine (260 ug). En revanche, "In Vitro", la présence de 2600 ug en ionophore entraîne une diminution significative des phénomènes de sécrétion, révélés à travers la radioactivité retrouvée au niveau de la paroi musculaire et des transudats, ceci étant associé à un retard de l'estérification et à des perturbations morphologiques de l'appareil de Golgi. "InVivo", les résultats confirment et précisent ceux obtenus "In Vitro" avec une diminution significative des lipides radioactifs retrouvés au niveau de la lymphe mésentérique associée à une réduction du flux lymphatique et du pourcentage de chylomicrons. Les résultats précédemment obtenus sont corroborés et confortés par des expériences conduites avec fortes molarité en lipides. Une relation "lipides-monensine" est observée permettant de mettre en évidence l'influence de la dose de monensine sur l'absorption des lipides.
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Geronilla, Kenneth B. "The quantification of oscillatory force parameters that affect eccentric contraction induced injury in an in vivo rodent." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1851.
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Thesis (M.S.)--West Virginia University, 2001.Title from document title page. Document formatted into pages; contains vii, 65 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 59-62).
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Oliveira, Elizabeth Maria Costa de. "Avaliação funcional, in vitro e in vivo, de ilhotas pancreáticas humanas nuas e microencapsuladas." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-22012015-165806/.
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Diabetes mellitus tipo 1 resulta da produção insuficiente ou da ausência de insulina, decorrente da destruição de células β, por mecanismo auto-imune. O tratamento deste tipo de diabetes consiste na administração subcutânea de insulina exógena. Recentemente, foi demonstrado que o transplante de ilhotas pancreáticas é capaz de tornar o portador de diabetes tipo 1 independente de insulina exógena. Apesar do sucesso alcançado, a necessidade permanente de imunossupressão é uma das principais barreiras para que o transplante de ilhotas possa ser realizado em número maior de pacientes. Assim, o desenvolvimento de novas metodologias que evitem a rejeição do enxerto, como o macro e o microencapsulamento de ilhotas, continua sendo crucial para o estabelecimento definitivo do transplante de ilhotas como opção terapêutica no tratamento de diabetes tipo 1. Neste trabalho, foi padronizado um modelo animal para avaliar, in vivo, a funcionalidade das ilhotas pancreáticas humanas isoladas e purificadas na Unidade de Ilhotas Pancreáticas Humanas do IQUSP. Ratos NIH nude foram tornados diabéticos através de injeção de estreptozotocina para o implante de ilhotas pancreáticas humanas nuas e microencapsuladas. As ilhotas foram microencapsuladas em Biodritina, um novo heteropolissacarídeo patenteado e cedido ao nosso laboratório, tendo sido possível padronizar a produção de microcápsulas uniformes e homogêneas, com tamanho médio entre 400µm e 600 µm. A reversão do diabetes ocorreu em 24% dos ratos nude transplantados com ilhotas pancreáticas humanas nuas. Por outro lado, não observamos reversão do diabetes quando ilhotas encapsuladas foram implantadas, apesar do teste de atividade funcional realizado in vitro ter demonstrado que elas continuam a secretar insulina e a responder ao estímulo com glicose após o encapsulamento. Para elucidar este efeito, cápsulas vazias foram implantadas em ratos nude e em ratos imunocompetentes, os quais desenvolveram processo inflamatório acompanhado de processo fibrótico no local do implante. Estudo imuno-histoquímico está sendo realizado para esclarecer a natureza e a intensidade destes processos.Type 1 diabetes mellitus results from insufficient or absence of insulin production, as a consequence of destruction of pancreatic β cells, by an auto-imune mechanism. Treatment for this type of diabetes consists of subcutaneous administration of exogenous insulin. Recently, it has been demonstrated that pancreatic islet cell transplantation is capable of rendering type I diabetic patients independent of exogenous insulin. However, in spite of the success achieved, permanent immunosuppression is still required, being the main barrier to expand this treatment to a large number of patients. Therefore, development of new technologies, such as islet macro and microencapsulation to avoid rejection of the tissue implanted, is still crucial for definitive establishment of islet transplantation as a therapeutic alternative for type I diabetes. In the present work, an animal model was established for in vivo evaluation of the functional ability of human pancreatic islets, which were isolated and purified at the Human Pancreatic Islet Unit of the University of São Paulo Chemistry Institute. Diabetes was induced in NIH nude rats through streptozotocin injection followed by implantation of naked or microencapsulated human pancreatic islets. Biodritin, a new and patented heteropolyssaccaride was used to microencapsulate the islets. The production of uniform and homogeneous microcapsules with diameters in the range of 400µm e 600 µm was successfully established. Reversion of diabetes occurred in 24% of the nude rats transplanted with human pancreatic islets. On the other hand, no reversion of diabetes was observed when encapsulated islets were implanted, although their functional activity in vitro indicated that they secreted insulin and responded to glucose stimulation upon encapsulation. In order to elucidate this effect, empty capsules were implanted in nude rat and in immunocompetent rats, both of which developed an inflammatory process accompanied by a fibrotic process in the site of the implant. Immunohistochemical studies are underway to address the nature and the intensity of these inflammatory processes.
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Henriksnäs, Johanna. "Helicobacter pylori and Gastric Protection Mechanisms : An in vivo Study in Mice and Rats." Doctoral thesis, Uppsala universitet, Institutionen för medicinsk cellbiologi, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-5898.
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The stomach is frequently exposed to hazardous agents and to resist this harsh environment, several protective mechanisms exist. Of special interest is the gastric pathogen Helicobacter pylori which causes gastritis, ulcers and cancer but the mechanism leading to these diseases are still unclear. However it is very likely that H. pylori negatively influence the protection mechanisms that exist in the stomach. The aims of the present investigation were first to develop an in vivo mouse model in which different protection mechanisms could be studied, and second to investigate the influence of H. pylori on these mechanisms. An in vivo preparation of the gastric mucosa in mice was developed. This preparation allows studies of different gastric mucosal variables and can also be applied for studies in other gastro-intestinal organs. Mice chronically infected with H. pylori, were shown to have a reduced ability of the mucosa to maintain a neutral pH at the epithelial cell surface. This could be due to the thinner inner, firmly adherent mucus gel layer, and/or to defective bicarbonate transport across the epithelium. The Cl-/HCO3- exchanger SLC26A9 was inhibited by NH4+, which also is produced by H. pylori. The mRNA levels of SLC26A9 were upregulated in infected mice, suggesting a way to overcome the inhibition of the transporter. Furthermore, the hyperemic response to acid pH 2 and 1.5 was abolished in these mice. The mechanisms by which the bacteria could alter the blood flow response might involve inhibition of the epithelial iNOS. Water extracts of H. pylori (HPE) reduces the blood flow acutely through an iNOS and nerve-mediated pathway, possibly through the endogenous iNOS inhibitor ADMA. Furthermore, HPE alters the blood flow response to acid as the hyperemic response to acid pH 0.8 is accentuated in mice treated with HPE.
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Rajikan, Roslee. "Absorption and metabolism of [2-¹â´C]quercetin-4'-glucoside in rats ex vivo and in vitro." Thesis, University of Glasgow, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433111.
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Kallincos, Nicholas Campbell. "Growth hormone (GH) and insulin-like growth factor-I (IGF-I) in vivo: investigation via transgenesis in rats /." Adelaide : Thesis (Ph.D.) -- University of Adelaide, Department of Biochemistry, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phk143.pdf.
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Kallincos, Nicholas Campbell. "Growth hormone (GH) and insulin-like growth factor-I (IGF-I) in vivo: investigation via transgenesis in rats." Thesis, Adelaide, 1993. http://hdl.handle.net/2440/21602.
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