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Rodrigues, Marciene Amorim. "Estudos moleculares, anat?micos e express?o g?nica de gen?tipos de bananeira contrastantes quanto ao despencamento dos frutos." Universidade Estadual de Feira de Santana, 2015. http://localhost:8080/tede/handle/tede/236.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The finger drop of banana is closely related to the maturation process and involves the softening and weakening of the pedicel. The aim of this study was to evaluate the genetic diversity of banana genotypes with contrasting levels of fruit finger drop by means of molecular markers and evaluate the susceptibility and resistance to finger drop from anatomical studies and analysis of gene expression via real-time quantitative PCR.The genotyping data generated by microsatellites was carried out based on the number of base pairs of each fragment and dendrogram cluster calculated by UPGMA method. Of the 30 microsatellite primer evaluated, 139 alleles were obtained, with the average of 4.66 alleles per locus. No relationship was found between the polymorphism detected by microsatellite markers and the degree of finger drop fruit. For the anatomical characterization, genotypes in the maturation stages 4, 5 and 6, and from different ploidy levels and finger drop resistance patterns, were used. In genotype 017041-01, susceptible, the presence of air parenchyma, was observed, a feature which was not evidenced in the resistant genotypes genotypes BB France, Khai Nai and BRS On Preciosa. Higher values of variable AF and increased deposition of lignin in the vascular bundles, were related to finger drop resistance. The values of Ct (cycle threshold) were used to determine the gene expression difference on cell wall modifier genes (PEL1, EXP1 and XTH4) between different stages of maturation in the finger drop zone (ZD) and in the middle of the fruit (control zone-ZC). To perform the analysis of relative expression, the 2? ?? CT method, was used. RT-qPCR analysis showed that there was a differential expression between the stages of maturation. Ploidy levels and resistance patterns, did not show correlation with the results of the expression. Genes XTH4 and PEL1 showed expression profiles related to finger drop in fruits in different genotypes being good candidates for functional studies in bananas, and may be useful in strategies of genetic improvement aiming the production of banana fruits with resistance to finger drop.
O despencamento natural dos frutos da bananeira est? estreitamente relacionado com o processo de matura??o e envolve o amolecimento e enfraquecimento do pedicelo. O objetivo deste trabalho foi estudar a diversidade gen?tica de gen?tipos de bananeira com n?veis contrastantes ao despencamento dos frutos por meio de marcadores moleculares e avaliar a suscetibilidade e resist?ncia ao despencamento a partir de estudos anat?micos e an?lise de express?o g?nica via PCR quantitativo em tempo real. A genotipagem dos dados gerados pelos microssat?lites foi realizada com base no n?mero de pares de base de cada fragmento e para o agrupamento no dendrograma, utilizou-se o m?todo UPGMA. Dos 30 iniciadores microssat?lites avaliados, obteve-se 139 alelos, com m?dia de 4,66 alelos por loco. N?o foi observada rela??o entre o polimorfismo detectado pelos marcadores microssat?lites e o grau de despencamento dos frutos Para a caracteriza??o anat?mica, foram utilizados gen?tipos nos est?dios de matura??o 4, 5 e 6, de diferentes ploidias e padr?es de resist?ncia ao despencamento. No gen?tipo suscet?vel 017041-01 foi observada presen?a marcante de par?nquima aer?fero, caracter?stica que n?o foi evidenciada nos gen?tipos resistentes BB Fran?a, Khai Nai On e BRS Preciosa. As mudan?as anat?micas, observadas durante o amadurecimento nos est?dios de matura??o, foram mais evidentes no gen?tipo suscet?vel 017041-01. Maiores valores da vari?vel AF e maior deposi??o de lignina nos feixes vasculares mostraram-se relacionados ? resist?ncia ao despencamento. Os valores dos Ct (cycle threshold) foram utilizados para determinar a diferen?a da express?o g?nica relativa dos genes modificadores da parede celular (PEL1, EXP1 e XTH4) entre diferentes est?dios de matura??o na zona de despencamento (ZD) e na regi?o mediana da casca (zona controle - ZC). Para realizar a an?lise de express?o relativa, foi utilizado o m?todo 2? ?? CT. Os resultados finais da an?lise por RT-qPCR mostraram que houve uma express?o diferencial entre os est?dios de matura??o nos gen?tipos estudados. Os genes PEL1 e XTH4 demonstraram perfis de express?o relacionados com o despencamento dos frutos em diferentes gen?tipos sendo bons candidatos para estudos funcionais em bananeira, podendo ser utilizado para direcionar o programa de melhoramento da cultura visando ? produ??o de frutos com resist?ncia para essa caracter?stica.
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Cobeña, Ruiz Gloria Annabell. "Relação entre componentes da parede celular e atividade enzimática no pedicelo e a suscetibilidade de bananas ao despencamento natural." Universidade Federal de Viçosa, 2003. http://www.locus.ufv.br/handle/123456789/10309.
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Programa de Modernización del Sector Agropecuario
Um dos maiores problemas na comercialização de bananas é o destacamento individual dos frutos das pencas, fazendo que estes percam ou diminuam seus valores comercial e nutricional, além de contribuir para que as perdas pós-colheita atinjam cerca de 40% da produção brasileira. O presente trabalho teve como objetivos caracterizar o comportamento dos componentes da parede celular, de amido e açúcares solúveis; determinar a atividade enzimática de poligalacturonase (PG), pectinametilesterase (PME) e xilanase na região do pedicelo de duas variedades e um híbrido de banana resistente e suscetível ao despencamento natural durante o amadurecimento; e estabelecer a relação entre o comportamento dos componentes da parede celular e a atividade enzimática, bem como a suscetibilidade de bananas à queda natural. Foram utilizados os genótipos triplóides ‘Terra’ (AAB) e ‘Prata’ (AAB) e o híbrido tetraplóide SH-3640 (AAAB). Os resultados evidenciaram uma diferença de comportamento na consistência da polpa entre os genótipos estudados, com a ressalva de que ‘Terra’ apresentou a maior consistência em todos os seus estádios de amadurecimento, seguido de ‘Prata’ e ‘SH-3640’. Verificou-se também que o genótipo ‘Terra’ mostrou resistência ao despencamento, mesmo estando seus frutos maduros, ao contrário de ‘SH-3640’, que, já a partir do estádio 5 (fruto amarelo com pontas verdes), exibiu suscetibilidade à queda. Em todos os estádios de amadurecimento, o genótipo ‘Terra’ teve os maiores teores de matéria seca. Por sua vez, o genótipo ‘SH-3640’ sempre manteve os mais baixos teores. Quanto à taxa respiratória, embora se tenha elevado com o amadurecimento, em nenhum dos três genótipos estudados foi observado comportamento climatérico típico. Do total das frações dos carboidratos estruturais (celulose, hemicelulose e pectina) e não-estruturais (amido, açúcares solúveis redutores e não-redutores), os genótipos ‘SH-3640’ e ‘Prata’ tiveram por volta de 80 e 70% de carboidratos estruturais no fruto verde, mantendo-se relativamente constantes durante o amadurecimento. Nesses cultivares, houve redução na proporção de amido e aumento na de açúcares solúveis, principalmente dos redutores. Já o genótipo ‘Terra’ apresentou variações mais evidentes com relação aos outros dois. Nesse genótipo, diminuíram os teores de pectinas no decorrer do amadurecimento, enquanto os de amido se mantiveram altos mesmo no fruto maduro. Entre as enzimas estudadas, os resultados evidenciaram um papel mais importante de PME e PG na queda de fruto e confirmaram a maior resistência do genótipo ‘Terra’ ao despencamento, permitindo concluir que PG e PME são as enzimas-chave na solubilização da parede celular que acompanha o amadurecimento e, portanto, têm papel fundamental na indução do despencamento natural. A alta suscetibilidade ao genótipo SH-3640 ao despencamento está associada à elevada atividade de PG e PME e ao baixo teor de matéria seca; a maior resistência ao despencamento do genótipo ‘Terra’ está relacionada com o maior acúmulo de matéria seca e amido no pedicelo.
One of the greatest problems for banana commercialization is finger drop of ripe bananas from the bunch since the market as well as the nutritional value of such isolated fruits is reduced or lost. This contributes to post-harvest losses of about 40% of the Brazilian production. In this study, the behavior of the cell wall components, starch, and soluble sugars was characterized; the enzymatic activity of polygalacturonase (PG), pectinmetylesterase (PME), and xylanase in the pedicel region of two varieties and one hybrid determined; and the relation between the behavior of cell wall components, enzyme activities in the pedicel, and the susceptibility of bananas to natural fruit dropping established. The triploid genotypes ‘Terra’ (AAB) and ‘Prata’ (AAB), and the tetraploid hybrid SH- 3640 (AAAB) were used. Results showed a difference in the pulp consistence of the studied genotypes. ‘Terra’ presented the highest consistence throughout all ripening stages, followed by ‘Prata’ and then ‘SH-3640’. Even when the fruits were ripe, ‘Terra’ was most resistant against fruit dropping, while ‘SH-3640’ began to present a high susceptibility to fruit dropping from stage 5 on (yellow fruits with green tips). At all ripening stages, ‘Terra’ presented the highest dry matter content, while ‘SH-3640’ continuously maintained the lowest content. In none of the studied genotypes the respiration rate obeyed a typical climacteric behavior, in spite of increases during the ripening process. Of all carbohydrate structural (cellulose, hemicellulose, and pectin) and non-structural (starch, soluble reducing and non-reducing sugars) fractions, the genotypes ‘SH-3640’ and ‘Prata’ contained around 70 and 80%, respectively, of structural carbohydrates in the green fruits. This proportion remained relatively constant during the ripening process. In these cultivars, there was a reduction in the starch proportion and an increase of soluble sugars, mainly of reducing sugars. The genotype ‘Terra’, on the other hand, presented more evident variations than the other two: there was a reduction of pectin contents during the ripening process (from 2.1 to 0.47%), while the starch contents remained above 2% even in ripe fruit. The ’Terra’ genotype proved to be the most resistant against fruit dropping. Results evidenced the importance of PG and PME for the degradation, or simply, the solubilization of cell wall components during the ripening process, and, therefore, for natural fruit dropping. The high susceptibility of the SH-3640 genotype is related to the high PG and PME activity and the low dry matter content. In the case of ‘Terra’, the high resistance to finger drop is related to a greater accumulation of dry matter and starch in the pedicel.
Não foram localizados o cpf e o curriculo lattes do autor.
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Amanzougaghene, Nadia. "Résistance et évolution des poux humains, Pediculus Humanus." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0268.
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Dans ce travail, nous avons voulu apporter notre contribution dans le domaine de la recherche sur les poux humains, afin d’en savoir plus sur l’origine et la phylogéographie des clades, les pathogènes qui leurs sont associés et comprendre les mécanismes impliqués dans la résistance à l’ivermectine. Nous avons obtenu des résultats concrets dans chacune des thématiques abordées. En effet, nous avons (i) pour la première fois rapporté la présence de clade B au Moyen-Orient datant de plus de 2000 ans, supportant une origine asiatique pour ce clade, (ii) mis en évidence l'existence d'un nouveau clade mitochondrial (Clade F), (iii) mis en place une nouvelle technique de PCR en temps réel pour l’identification moléculaire rapide des clades de poux, (iv) mis en évidence chez des poux de tête la présence de l’ADN de plusieurs bactéries, dont plusieurs bactéries qui ne sont pas habituellement vectorisées par les poux telles que Coxiella burnetii, Rickettsia aeschlimannii et de potentielles nouvelles espèces de genre Anaplasma et Ehrlichia ont été détectées pour la première fois chez les poux. Enfin, nous rapportons des données nouvelles sur la résistance des poux à l’ivermectine : (v) en mettant en évidence la présence de trois mutations non-synonymes au niveau de GluCl des poux cliniquement résistants à l’ivermectine, (vi) et en démontrant, pour la première fois, chez une population de poux de laboratoire résistante à l’ivermectine qu’une répression significative de la complexine est à l’origine de la résistance. Cette découverte représente la première évidence liant la complexine à la résistance aux insecticidesIn this thesis, we are interested in studying human lice and we aimed to learn more about the origin and phylogeography of clades, lice-borne associated pathogens and to investigate potential mechanisms underlying resistance to ivermectin in lice. We obtained concrete results that have led to scientific publications. Indeed, (i) we reported for the first time the existence of the clade B in the Middle East, dating approximately to 2,000 years old, supporting an Asian origin for this clade, (ii) we highlighted the existence of a sixth mitochondrial clade (Clade F), (iii) we developed a new qPCR for a quick molecular identification of all the known clades of lice, (iv) we identified the presence of the DNA of several bacterial pathogens in head lice, among which several bacteria are not usually associated with lice, such as Coxiella burnetii, Rickettsia aeschlimannii, Borrelia theileri and potential new species from the Anaplasma and Ehrlichia. We finally, investigated mechanisms underlying resistance to ivermectin in lice: (v) we have identified, for the first time, the occurrence of three non-synonymous mutations in GluCl gene in clinically confirmed ivermectin resistant head lice, (vi) and we have identified the involvement of neuronal protein, a complexin, in laboratory ivermectin-selected resistant lice. This finding represents the first evidence linking complexin to insecticide resistance
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Nevière, Rémi. "Oxygenotherapie hyperbare et lambeaux pedicules : etude de la survie de 15 lambeaux pedicules : valeur predictive de la mesure des po2 transcutanees." Lille 2, 1989. http://www.theses.fr/1989LIL2M274.
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Boyadjis, Melanie. "Intraoperative neurophysiological monitoring through pedicle screw stimulation." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/672359.
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OBJECTIVES: Study the interdependence between stimulus duration and stimulus strength, to observe if by changing the stimulus duration, the current threshold levels will also change during pedicle screw stimulation. Then comparing the pedicle screw threshold data to 3-Dimensional imaging to confirm the effectiveness of pedicle screw stimulation.
BACKGROUND: This study examined the stimulus parameters of triggered electromyography in the operating room during posterior spinal fusions with pedicle screw fixation, and how changing stimulus duration would affect the threshold value of a pedicle screw. Triggered Electromyography (t-EMG) or pedicle screw stimulation has been used for years as Gold Standard to test whether pedicle screws are properly placed or well insulated by bone in the pedicle of the vertebrae. In a triggered EMG test, a stimulus is sent to the pedicle screw, when the electrical stimulus activates nervous tissue, a compound muscle action potential is elicited, at this point a current threshold value is recorded. This threshold is compared to normative values, which determine if the screw is located intrapedicular or has breached the pedicle wall. A breach in the pedicle wall by a pedicle screw would cause a post-operative neurological deficit, such as nerve irritation. To examine the effects duration has on threshold values, the same screw was stimulated three different times with three different durations. The threshold values were statistically evaluated to see if there was a significance between each stimulus duration and its corresponding threshold value. Duration was examined because it is often overlooked as a parameter that may change the threshold value of a triggered EMG test. Having discrepancies due to duration can produce inaccurate results which could potentially harm the patient or change the surgical protocol. It may harm the patient by leaving a screw in place that has breached the pedicle wall of a vertebrae, which will most likely cause post-operative nerve irritation. Pedicle screw stimulation is an additional modality used to verify screw placement along with radiographic imaging in the operating theatre when posterior spinal fusions are taking place.
METHODS: The current technique of pedicle screw stimulation using threshold numbers (in milliamperes) was evaluated against different stimulation parameters, and later the position of the screw was visually verified by a neurosurgeon with 3-dimensional imaging. Fundamentally, the imaging was used to validate the effectiveness that pedicle screw stimulation has on determining a well-positioned screw. Patients already scheduled to undergo spinal fusions with pedicle screw fixation were eligible for this study. A 3-Dimensional (3D) image of their spine was taken intraoperatively before insertion of spinal fixation instrumentation and one was taken after pedicle screws were inserted. These images were used to evaluate the position of the pedicle screw by a neurosurgeon. After screws were positioned, triggered EMG was utilized to check whether screws were properly placed. Screw measurements were taken from patients undergoing a posterior spinal fusion in either the thoracic, lumbar or sacral region. 213 screw measurements were taken in total from 40 patients. Factors like sex, age, height and weight were not considered for this study. The triggered EMG test threshold was then compared to the post screw insertion 3D image to verify the accuracy of the triggered EMG. In other words, the image was used to justify whether the triggered EMG test alone was an accurate indicator of a properly placed screw. In addition, the triggered EMG test itself was further evaluated, by stimulating the same screw three times, with three different stimulus durations, 300µsec, 200µsec, and 100µsec. The values produced by each stimulus duration were then compared to the corresponding stimulus threshold to see if there was a significant difference. Triggered EMG stimulus durations were assessed to see if stimulus parameter settings play a role in the threshold number. A change in stimulus duration, could change the triggered EMG threshold number, which when compared to normative data could possibly indicate a properly placed screw from a mal-positioned screw with a difference in threshold of as little as 1 milliampere. From all the stimulus parameters, a focus was put on the stimulus duration because this could directly affect the triggered EMG current threshold number, or the current value where a compound muscle action potential is elicited.
Which depending on where the threshold value fell against pre-determined normative values, could directly affect whether a screw is interpreted as well-placed or not. To summarize, each pedicle screw was tested three times, at three different stimulus durations, then the corresponding threshold numbers were compared to currently established normative data thresholds and evaluated to see if duration could affect the results of a pedicle screw’s position. Remember, thresholds have been established that deem a properly placed screw, these have been used throughout the years, but no emphasis has been given to the stimulus parameters set for these thresholds. This study evaluated the importance of setting the proper stimulus parameters, mainly the stimulus duration, when using certain normative thresholds tested at specific durations to deem a properly positioned screw in the pedicle of a vertebrae. After stimulation, 3D imaging was taken intraoperatively to compare the triggered electromyography data to the actual placement of the screws. The threshold values were compared to the 3 D image of the same screws tested, to verify if indeed these established threshold values determined well-positioned screws.
RESULTS: 213 screws were stimulated, out of the 213 screws, 2 screw measurements were excluded because stimulations were not obtained from all three durations. Thus 211 screws and 40 patients were included in this study. 211 screw measurements were taken in total from 40 patients with screws confirmed to be placed intrapedicular. The triggered EMG fell within normative data thresholds for 206 screws (98%), these screws were found to be intrapedicularly placed in the 3D imaging, which was confirmed by the neurosurgeon. Stimulation durations were found to be important in five of the screws, where there was a difference in the thresholds between the three stimulations, these were significant because the values were lying borderline on normative values, questioning if the screws were indeed well-placed or possibly causing a medial breach. These five screws were thoroughly examined by the neurosurgeon via 3-dimensional imaging and were found to be acceptable in placement, and not near nervous tissue.
CONCLUSION: Intraoperative 3D imaging has shown that triggered electromyography is a reliable indicator of properly placed pedicle screws. Statistical data has also shown that stimulus duration can affect the interpretation of a properly placed screw, and threshold values do vary with different durations. Threshold values were gathered from 211 screws at three different stimulus durations, the first at 300µsec, the second at 200µsec and the third at 100µsec. At 300µsec stimulus duration, the mean threshold value was at 27.25mA (p=0.0078). At 200µsec stimulus duration, the mean threshold value was at 35.46mA (p=0.0028). At 100µsec stimulus duration, the mean threshold value was at 50.90mA (p=0.0676). These mean values were found to be statistically significant when run by the Kruskal-Wallis test, a non-parametric statistical significance test. Since, three groups of data were being compared, and thus were not normally distributed, a non-parametric significance test was used. In conclusion, the stimulus duration should be considered when using certain thresholds to interpret data.
Different durations change the stimulus strength and thus, affect the results of the screw stimulation thresholds.
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BAPTISTA, LOUIS. "Lambeaux fascio-cutanes pedicules des membres : classification et repertoire." Toulouse 3, 1990. http://www.theses.fr/1990TOU31210.
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Peock, Susan. "The screening, action and use of repellents against Pediculus humanus." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624578.
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Pereira, Marlon Cristian Toledo. "Caracterização, anatomia do pedicelo, fisiologia e redução do despencamento natural de bananas após a colheita." Universidade Federal de Viçosa, 2002. http://www.locus.ufv.br/handle/123456789/10242.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
O despencamento natural de bananas maduras é indesejável comercialmente, pois reduz o valor de mercado da fruta, bem como a sua aceitação pelos consumidores, o que pode inviabilizar o lançamento de novos cultivares. O presente trabalho teve como objetivos quantificar a suscetibilidade ao despencamento natural dos frutos de bananeira de diversos genótipos, de grupos genômicos e ploidias diferentes; obter subsídios para o melhoramento da bananeira; determinar as causas anatômicas e fisiológicas associadas ao despencamento natural de frutos de bananeira; identificar uma possível região ou camada de abscisão em frutos de bananeira; e verificar o efeito de aplicações na pré-colheita de cálcio na redução do despencamento natural dos frutos de bananeira. Os resultados evidenciaram alta resistência ao despencamento dos genótipos pertencentes ao grupo genômico BB (Butuhan, Piraí e BB França), ‘Terra’ (AAB), ‘Poteau Nain’ (tipo figo) (ABB) e ‘Thap Maeo’ (AAB), enquanto ‘Prata Anã’ (AAB), ‘Grande Naine’ (AAA), Ambrosia (AAAA), ‘Ouro’ (AA) e FHIA -18 (AAAB) apresentaram valores intermediários de resistência ao despencamento. Com relação às bananeiras com baixa resistência, destacam-se os híbridos melhorados Pioneira (AAAB), YB42-21 (AAAB), Bucaneiro (AAAA) e Calypso (AAAA) e o cultivar Ouro da Mata (AAAB). Verificou-se grau de associação de 74% entre a firmeza do fruto e a resistência ao despencamento natural. Ao contrário da maioria das plantas, na região de despencamento do fruto maduro da bananeira não foi detectado camada de abscisão. Em genótipos como Pioneira (AAAB), ‘Prata Anã’ (AAB) e ‘Lidi’ (AA), o tecido parenquimático do pedicelo degenerou-se nos frutos maduros, formando grandes espaços vazios, que justificam a maior suscetibilidade dos frutos de tais genótipos ao despencamento. O cultivar Terra (AAB), considerado resistente ao despencamento, possui fibras difíceis de serem separadas ou individualizadas e relativamente finas em relação às dos demais genótipos. Observou-se que os genótipos Butuhan (BB), ‘Poteau Nain’ (ABB) e ‘Thap Maeo’ (AAB), também resistentes ao despencamento, apresentaram fibras com paredes celulares bastante espessas. Verificou-se redução linear da resistência ao despencamento e do tempo de maturação do fruto com o incremento das concentrações de CaCl2. A firmeza não se alterou em relação às concentrações, porém em três aplicações de CaCl2 os frutos apresentaram-se mais consistentes do que com apenas uma aplicação. Os teores de cálcio da casca e da polpa dos frutos não foram alterados significativamente com as concentrações e épocas de aplicações do CaCl2, indicando baixa absorção desse nutriente quando aplicado em pré-colheita diretamente no fruto.
Natural fruit dropping of ripe bananas is commercially unwelcome, as it reduces the market value of the fruit as well as its consumer acceptance and may thwart the launch of new cultivars. In this study, goals were set as follows: quantification of the susceptibility to natural fruit dropping in fruits from different genotypes and different genomic groups and ploidies, obtainment of subsidies for banana improvement; determination of anatomical and physiological causes linked to natural dropping in banana fruits, identification of a possible abscission region or layer in banana fruits, and the verification of the effect of pre-harvest calcium application on the reduction of natural banana fruit dropping. Results showed a high resistance against fruit dropping among genotypes that belong to the genomic group BB ('Butuhan', 'Piraí' and 'BB França'), ‘Terra’(AAB), ‘Poteau Nain’ (fig type) (ABB) and ‘Thap Maeo’(AAB), while ‘Prata Anã (AAB), 'Grande Naine' (AAA), 'Ambrosia' (AAAA), ‘Ouro’ (AA) and 'FHIA –18' (AAAB) presented intermediate values of resistance against dropping. Among banana plants with low resistance, the improved hybrids Pioneira (AAAB), YB42-21 (AAAB), Bucaneiro (AAAA) and Calypso (AAAA) and the cultivar Ouro da Mata (AAAB) were outstanding. An association degree of 74% between fruit firmness and resistance against fruit dropping was established. In contrast to the majority of plants, no abscission layer was found in the region of dropping of ripe banana fruits. In genotypes like 'Pioneira' (AAAB), ‘Prata Anã’ (AAB) and ‘Lidi’ (AA), the pedicel parenchyma tissue was degenerated in the ripe fruits, forming large empty spaces, which justifies the higher susceptibility of the fruits of these genotypes to dropping. The ‘Terra’ cultivar, considered dropping resistant, owns relatively fine fibers, difficult to separate or individualize in comparison to t e h other genotypes. The genotypes 'Butuhan', (BB), ‘Poteau Nain’ (ABB) and ‘Thap Maeo’ (AAB), also dropping resistant, presented fibers with particularly thin cell walls. A linear reduction of the fruit dropping resistance and maturation period was verified in response to increased CaCl2 concentrations. The firmness did not alter in relation to the concentrations, however after three CaCl2 applications, the fruits proved to be more consistent than after only one application. Calcium contents in fruit pericarp and pulp did not vary significantly in relation to concentrations and periods of CaCl2 applications, indicating low absorption of this nutrient when applied directly on the fruit in pre-harvest.
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TOLEDANO, ELIE. "Neovascularisation d'un lambeau cutane expanse a pedicule monovasculaire : etude experimentale preliminaire sur le porc." Clermont-Ferrand 1, 1993. http://www.theses.fr/1993CLF1MS26.
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Gouraud, Gisèle. "Chimioprévention et traitements actuels des pédiculoses phénomènes de résistance." Paris 5, 1993. http://www.theses.fr/1993PA05P020.
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Keifer, Dorion Amanda. "Last lumbar facet and pedicle orientation in orthograde primates." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0010491.
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Edsander-Nord, Åsa. "Pedicled and free TRAM flaps in breast reconstructions : a comparative study /." Stockholm, 2000. http://diss.kib.ki.se/2000/91-628-4360-5/.
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Sangaré, Abdoul Karim. "Modèles expérimentaux de traitement in vitro et épidémiologie moléculaire chez les poux humains." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM5054/document.
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Les poux humains (Pediculus humanus) sont des ectoparasites hématophages, ayant vécu avec leur hôte pendant des milliers d’années. Durant cette thèse, nous avons d’abord élaboré une large bibliographie nous permettant de rédiger une revue, puis d’apporter des réponses à certains nombres de questions restées en suspens à travers le traitement de certaines thématiques qui nous semblaient importantes. En effet, nous avons (i) démontré que les poux de tête et les poux de corps en Afrique peuvent être infectés par B. quintana quand les patients vivent dans des conditions économiques pauvres et sont aussi exposés aux poux de corps; identifié pour la première fois le clade mitochondrial des poux de tête du Mali, Kenya, Congo et Madagascar, et confirmé celui du Sénégal, Algérie, Ethiopie, Rwanda et Burundi, (ii) démontré que les poux de tête et les poux de corps chez les SDF doublement infestés appartiennent à la même population de poux de corps, et dans les conditions d’infestation massive, les poux de corps peuvent migrer et coloniser les cheveux et vice-versa, (iii) prouvé la nécessité de réaliser des enquêtes épidémiologiques nationales sur la pédiculose dans les régions du Mali, (iv) démontré par le modèle in vitro que la doxycycline a un effet direct sur la bactérie endosymbionte du pou Candidatus Riesia pediculicola via le mycetome. Ce dernier travail nous a permis de mettre en exergue l’efficacité synergique des antibiotiques + ivermectine permettant de lutter plus efficacement l’infestation des poux et éviter l’apparition de résistance. Ce travail a fait l’objet de dépôt d’un brevetHuman lice (Pediculus humanus) are bloodsucking ectoparasites, having lived with their host for thousands of years. During this thesis, we first developed an extensive bibliography allowing us to write a review and provide answers to certain number of questions remained pending through treating some thematic that seemed us significant. Indeed, we have (i) demonstrated that head and body lice in Africa can be infected with B. quintana when patients live in poor economic conditions and are also exposed to body lice; identified for the first time the mitochondrial clade of lice Mali, Kenya, Congo and Madagascar, and confirmed that of Senegal, Algeria, Ethiopia, Rwanda and Burundi, (ii) demonstrated that head and body lice in SDF doubly infected belong to the same population of body lice, and under conditions of massive infestation, body lice can migrate and colonize the hair and vice versa, (iii) proved the need to make national epidemiological surveys on pediculosis in areas of Mali, (iv) demonstrated by in vitro model that doxycycline has a direct effect on endosymbiont bacteria of louse Candidatus Riesia pediculicola via mycetoma. This last work allowed us to highlight the synergistic efficacy of ivermectin + antibiotics to fight more effectively the infestation of lice and avoid the appearance of resistance. This work was subject of a patent
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Murray, Rebecca Anne [Verfasser], and Michael M. [Akademischer Betreuer] Morlock. "Pedicle screw fixation / Rebecca Anne Murray. Betreuer: Michael M. Morlock." Hamburg-Harburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2014. http://d-nb.info/1058626175/34.
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Choi, Yi-king, and 蔡綺瓊. "Computer visualization techniques in surgical planning for pedicle screw insertion." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31224234.
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Choi, Yi-king. "Computer visualization techniques in surgical planning for pedicle screw insertion /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B22956475.
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Murray, Rebecca Anne [Verfasser], and Michael [Akademischer Betreuer] Morlock. "Pedicle screw fixation / Rebecca Anne Murray. Betreuer: Michael M. Morlock." Hamburg-Harburg : Universitätsbibliothek der Technischen Universität Hamburg-Harburg, 2014. http://nbn-resolving.de/urn:nbn:de:gbv:830-tubdok-12861.
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Lewis, Susan Elisabeth. "Studies on the developmental biology of the human louse Pediculus humanus linnaeus." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385444.
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Candy, Kerdalidec. "Etude des mécanismes d'action des huiles essentielles/minérales pédiculicides." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0287.
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L'émergence de la résistance des poux aux insecticides neurotoxiques ont favorisé le développement de nouveaux pédiculicides à action « mécanique » à base d’huile. Mais le mécanisme précis d’action de ces produits était mal connu. Dans ce travail, nous nous sommes intéressés aux modes d’action de 5 huiles essentielles pédiculicides et d’une huile minérale, la diméticone également pédiculicide. Dans une première étape, j’ai évalué l’efficacité pédiculicide des huiles essentielles. Seule Eugenia caryophyllata s’est révélée très efficace, Litsea cubeba, a montré une efficacité relative. Dans une deuxième étape, j’ai évalué la résistance des poux à la noyade et à l’anoxie, mécanismes d’action revendiqués pour les produits huileux. Alors que les poux résistent jusque 24 h dans l’eau sans se noyer, ils se noient rapidement et meurent dans la diméticone, en moins de 30 min. Les poux meurent également par noyade lorsqu’ils sont immergés dans les composants biochimiques des huiles étudiées. Les poux résistent à l’anoxie jusque 14 h. Dans une troisième étape, l’activité neurotoxique des principaux composants des huiles a été évaluée sur la blatte, Periplaneta americana, seul modèle disponible pour ce travail. Selon la technique du patch-clamp, aucune activité électrophysiologique n’est décelée aux concentrations habituellement utilisées. Enfin, nous avons étudié le génotypage des poux utilisés. Les poux de Bobigny appartiennent à 3 clades : A, B et E. Le clade E est noté pour la première fois en région parisienne. Les agents pathogènes hébergés par ces poux ont été recherchés et nous notons pour la première fois la présence de Bartonella quintana dans les poux de corps de BobignyThe emergence of resistance in Pediculus h. capitis, to chemical-based insecticides has result the development of "mechanical" oil-based pediculicides. Despite this interest, little is known on the precise mechanism of action of these products. In the current thesis, we have concentrated on the modes of action of 5 essential oils commonly used as pediculicides as well as one mineral oil, dimeticone. At the first step, the pediculicidal efficacy of essential oils was evaluated by in-vitro bioassay. Among oils examined, only E. caryophyllata has proved to be very effective followed by Litsea cubeba. In the second step, the resistance of head lice to drowning and anoxia was assessed. The lice were resistant up to 24 h in the water without drowning whereas they were quickly drown and died in the dimeticone, in less than 30 min. In addition, the lice were died by drowning during immersion in the pure biochemical components of essential oils. In the same way, the lice were resistant to anoxia up to 14 h in an enclosed box without oxygen. In the third step, the neurotoxic activity of the main components derived from mentioned essential oils were analyzed on the cockroach, Periplaneta americana as the sole model available. According to the patch-clamp technique, no electrophysiological activity was detected using habitual concentrations. Finally, the bacterial flora of mentioned specimens was studied using molecular analysis. Based on our results, Bartonella quintana was detected for the first time in the body lice collected in Bobigny. According to the genotyping results, the lice of Bobigny belong to three clades of A, B and E. The latter is newly reported in the current thesis
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Asadollahi, Mohammad Saeid. "Biomechanical Evaluation of Novel Expanding Pedicle Screws Suitable for OsteoporoticLumbar Spine." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449711700.
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KATTAN, VILLENEUVE MARIE-BERNADETTE. "A propos d'un hemangiome caverneux du foie, pedicule et volvule chez un adulte." Clermont-Ferrand 1, 1990. http://www.theses.fr/1990CLF11002.
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Seyed, Vosoughi Ardalan. "Mitigating the Biomechanical Complications Following Pedicle Subtraction Osteotomy: A Finite Element Analysis." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1503598742789914.
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Sakamoto, Takeshi. "Transpedicular screw placement evaluated by axial computed tomography of the cervical pedicle." Kyoto University, 2004. http://hdl.handle.net/2433/145277.
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Souffez, Marie-France. "Des insectes et des hommes : les représentations du pou dans la culture andine." Paris 10, 2001. http://www.theses.fr/2001PA100151.
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Cette thèse a pour objet l'étude des représentations du pou dans la culture andine aux XVIème, XVIIème et XXème siècle. En premier lieu (XVIème et XVIIème siècles) sont présentés et analysés des écrits de chroniqueurs et autres auteurs 1-sur des coutumes amérindiennes et surtout péruviennes à l'égard des poux: manger les poux et donner des poux en tribut; 2-sur des "divinités" pouilleuses. En second lieu (XXème siècle), divers récits mythiques contemporains sur l'origine des poux sont analysés: 1-un monstre femelle et cannibale est brûlé et de ses cendres naissent les différents parasites de l'homme et des animaux (poux, puces, tiques); 2-l'Esprit ou le Dieu céleste de tous les mondes et de tous les temps ainsi que du début du temps actuel donne de nombreux poux blancs de corps à des hommes ou femmes qui sont des paresseux incorrigibles mais qui alors doivent s'épouiller. Le premier mouvement commence dans un monde immobile mais cette activité est solitaire; 3-un pou noir de tête est donné à l'homme par l'Esprit ou le Dieu céleste du Monde et du temps actuel. En conséquence naît le premier dialogue entre l'homme et la femme, ce qui provoque l'émergence de la conscience de la distinction entre le masculin et le féminin, les humains et les animaux. Les êtres vivants se regroupent par espèces, s'unissent en couple masculin féminin à l'intérieur de chaque espèce et sont féconds. Le couple humain travaille de façon complémentaire ce qui apporte la prospérité à la famille. Mais un conflit cosmique oppose l'Esprit céleste (qui a donné à l'homme le pou noir de tête) et l'Esprit souterrain, envieux de la nouvelle capacité humaine (le dialogue). Les armées de cet Esprit jaloux sont des animaux opposés au pou noir de tête, ennemis du dialogue, de l'épouillage et de l'amour mutuel, du travail complémentaire dans le couple et surtout du fruit de l'union de ce couple:l'enfant, qui sont le fondement de l'équilibre fragile du cosmos. En troisième lieu vient un long développement sur les étoiles des crépuscules qui dans la pensée andine du XXème siècle semblent en partie liées à l'Esprit souterrain ennemi de la reproduction humaine, animale et végétaleThe purpose of this thesis is the study of the views of buse m deân culture in the XVI, XVII and XX centuries. First (XVI and XVII centuries), are exposed writings of chroniclers and others authors about amerindian and especially peruvian lice practices: eating lice and lice tributes. Then, are presented chronicles and idolatry proceedings writings about lousy "gods". Third (XX century), some contemporary mythical andean stories about the origin of lice reveals that the différent parasites of the men and the animals appear when one canibalistic female mounster is burned: her ashes turned into many lice, flea and ticks. In others stories, the celestial Spirit or God of all worlds and times and of the beginning of this world and time give numerous white body lice to incredibly lazy men or women who had to delouse themself. First activity and movement begin in the motionless world but it is a solitary work, a solitary human life. In anothers stories the analyses reveals that with the dark head louse (gived by the celestial Spirit or God of the actual world and time) appear suddenly the langage (dialogue) between first man and woman and, consequently, the conciousness of the distinction between man and woman, humans and animals, species. More consequently, occur the fruitfull union between man y woman and the masculine and feminine members of others species, the formation of human couple and masculine and feminine pairs in all species. More consequently, occur the interdependent and complementary work of the man and woman couple, that leads to prosperous family life. More and more consequently, an cosmic conflict begin between the celestial Spirit or God (who gave the dark head louse at man) and one subterranean Spirit or God envious of the new linguistic exchange quality of the human beings. The armies of this envions Spirit are animals opposites of dark head louse. They are the ennemies of linguistic exchanges, mutual delousing and love, complementary work and reproduction of human couple, that are the basement of this fragile actual cosmos. Twilight stars, tornados and others atmospheric plagues are the punitive armies of the subterranean Spirit for guilty men
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Honda, Goro. "Approach for systematic resection of the liver antero-superior area : exposing Glissonean pedicles by prior dissection of the major hepatic fissure." Kyoto University, 2009. http://hdl.handle.net/2433/126463.
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Sakai, Yoshihito, Yukihiro Matsuyama, Hisatake Yoshihara, Hiroshi Nakamura, Shojiro Nakashima, Naoki Ishiguro, 義人 酒井, et al. "Simultaneous registration with CT-fluoro matching for spinal navigation surgery." Nagoya University School of Medicine, 2006. http://hdl.handle.net/2237/6132.
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Eshghinejad, Ahmadreza. "Finite element study of a shape memory alloy bone implant." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1333726695.
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Bilhar, Romero Pinto de Oliveira. "Accuracy insert bolt pedicle: studyn comparing fluoroscopy and navigation in column chest of body." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17745.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorThe fixation with pedicle screw plays an important role in many spinal surgeries, providing excellent postoperative stability of the spine. It is currently the main form of instrumentation of thoracolumbar spine. The misplaced screws may cause not only a reduction in stability but, also, vascular, visceral or neurological lesions. Some methods adjuvant are used to increase the accuracy rate on the insertion of these, including intraoperative fluoroscopy and computer assisted navigation. In literature, we find studies evaluating the accuracy of these methods and comparing them, however among studies, the evaluation of the accuracy varies significantly, dificulting the interpretation and comparison.The main objective of this study was to compare the accuracy of pedicle screw insertion in the thoracic spine between the technique guided by fluoroscopy and by computer assisted navigation. In this study, 8 cadavers were used, divided into two groups: in group 1, 40 pedicle screws were inserteds with the aid of fluoroscopy, and in group 2, 40 screws with the aid of computerized navigation. There was one drilling error in each group, which resulted in an average of 2.5% of drilling error in each group. In group 1, it has been done 350 fluoroscopic images and in group 2 no image has been done. After statistical analysis, there was no statistically significant difference between the two techniques in this study, wich demonstrate the safe of the computer assisted navigation and the benefit of no exposition toradiation.
A fixaÃÃo com parafuso pedicular desempenha um papel importante em muitas cirurgias de coluna, proporcionando uma excelente estabilidade pÃs-operatÃria. Ã, atualmente, a principal forma de instrumentaÃÃo da coluna tÃraco-lombar. O mal posicionamento dos parafusos pode causar nÃo sà uma reduÃÃo da estabilidade, mas tambÃm lesÃes vasculares, viscerais ou neurolÃgicas. Alguns mÃtodos auxiliares sÃo utilizados para aumentar a taxa de acerto na inserÃÃo desses, entre elas a fluoroscopia intraoperatÃria e a navegaÃÃo computadorizada. Na literatura, encontramos estudos avaliando a acurÃcia desses mÃtodos e os comparando, porÃm entre os estudos, a avaliaÃÃo da acurÃcia varia significativamente o que dificulta a nterpretaÃÃo e comparaÃÃo entre eles. O objetivo do presente estudo foi comparar a acurÃcia da inserÃÃo de parafusos pediculares na coluna torÃcica entre a tÃcnica guiada por fluoroscopia e a guiada por navegaÃÃo computadorizada. No presente estudo, foram utilizados 8 cadÃveres, divididos em 2 grupos: no grupo 1, 40 parafusos pediculares foram inseridos com auxÃlio da fluoroscopia e, no grupo 2, 40 parafusos com o auxÃlio da navegaÃÃo computadorizada. Houve 1 erro de perfuraÃÃo em cada grupo, o que resultou em uma mÃdia de 2,5% de erro de perfuraÃÃo em cada grupo. No grupo 1 foram realizadas 350 imagens de fluoroscopia enquanto no grupo 2 nenhuma imagem foi feita. ApÃs anÃlise estatÃstica, nÃo houve diferenÃa estatisticamente significante entre as duas tÃcnicas no presente estudo, o que demonstra a seguranÃa da navegaÃÃo computadorizada com o benefÃcio de nesse Ãltimo mÃtodo nÃo ter havido exposiÃÃo do cirurgiÃo e sua equipe à radiaÃÃo.
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Shea, Thomas Michael. "Localized Expansion of Pedicle Screws for Increased Stability and Safety in the Osteoporotic Spine." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5308.
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When a patient is diagnosed with various spinal injuries, deformities, or advanced degeneration, it is commonly suggested that he/she undergoes surgery for spinal fusion. Most current procedures in spinal fusion restrict mobility in one or multiple levels of the spine so that, over time, new bone will grow between the levels creating a single motionless unit of bone. The bilateral pedicle screw system (BPSS) has long been considered to be the "gold standard" in spinal fusion. However, for patients with osteoporosis, adequate fixation within the bone-screw interface has continuously been difficult to achieve or has come with high risk of other forms of catastrophic damage. Reflecting this, a new pedicle screw design was developed and evaluated against current standard pedicle screws commonly used in spinal surgery. All screw designs were also tested with a common cement augmentation technique surrounding the circumference of the screw. All tests measured pullout strength, stiffness, energy to failure, toughness, and the amount of destruction to the surrounding synthetic bone. While the newly designed pedicle screw failed to produce significantly stronger pullout forces in comparison to the standard screws, it did show evidence of a longer lasting residual axial resistance and a safer mode of failure than the standard screw, hinting that the design may benefit individuals who experience screw pullout and are awaiting reinstrumentation.
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Wong, Corrine Jui Yin. "Three and four dimensional computed tomographic angiography of free and pedicled flaps : investigating the vascular territories." Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8387.
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In plastic surgery, flap reconstruction has been utilised to repair defects in every part of the body, in an effort to restore form and function to patients. The basis of every flap is its blood supply, therefore this series of studies investigates the vascular territory of named arteries, veins and even perforators, utilizing computer tomography (CT) and TeraRecon software. The latter two is technology which allows appreciation of vascular flow in 3D and 4D (dynamic studies), whereas previous studies of vascularity has only been static and in 2D. Vascular anatomy studies were performed using fresh cadavers. Perforator flaps on the anterior trunk studied were the internal mammary artery perforator (IMAP) flap, the transverse rectus abdominis musculocutaneous (TRAM) flap, the deep inferior epigastric artery perforator (DIEP) flap and the superficial inferior epigastric artery (SIEA) flap. Posterior trunk flaps included the posterior intercostal artery perforator flap, the lumbar artery perforator flap and the superior gluteal artery perforator (SGAP) flap. In the upper extremity, we studied the supraclavicular artery perforator flap. In the lower extremity, we studied the gracilis musculocutaneous flap. Trends and characteristics are noted in the vascular analyses, and four major principles drawn are discussed in the last chapter.
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Zhu, Yong. "An experimental approach to molecular typing of human lice (Pediculus humanus) and bacteria of the Rickettsia genus." Aix-Marseille 2, 2005. http://www.theses.fr/2005AIX20651.
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Semeria, Eric. "Le lambeau osteo-perioste de la region temporo-parietale : le lambeau pedicule de table externe de parietal." Aix-Marseille 2, 1988. http://www.theses.fr/1988AIX20195.
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Quillot, Marc. "Les lambeaux à pédicule sous-cutané dans la réparation des pertes de substance chirurgicales de la face." Montpellier 1, 1992. http://www.theses.fr/1992MON11112.
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Courtiade, Caroline. "La pédiculose du cuir chevelu : enquête épidémiologique dans quatre groupes scolaires de l'académie de Bordeaux en 1990-91." Bordeaux 2, 1992. http://www.theses.fr/1992BOR2M052.
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Doulgeris, James. "Biomechanical Comparison of Titanium and Cobalt Chromium Pedicle Screw Rods in an Unstable Cadaveric Lumbar Spine." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4812.
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Pedicle screw-rod instrumentation is considered a standard treatment for spinal instability, and titanium is the most common material for this application. Cobalt-chromium has several advantages over titanium and is generating interest in orthopedic practice. The aim of this study was to compare titanium versus cobalt-chromium rods in posterior fusion, with and without transverse connectors, through in vitro biomechanical testing and determine the optimal configuration.
Six cadaveric lumbar spines (L1-S1) were used. Posterior and middle column injuries were simulated at L3-L5 and different pedicle screw constructs were implanted. Specimens were subjected to flexibility tests and range of motion, intradiscal pressure and axial rotation energy loss were statistically compared among the following conditions: intact, titanium rods (without transverse connectors), titanium rods with transverse connectors, cobalt-chromium rods (without transverse connectors) and cobalt-chromium rods with transverse connectors. The novel measurement of energy loss was examined to determine its viability in fusion investigations.
All fusion constructs significantly (p0.05) were observed in axial rotation among all conditions. Intradiscal pressure significantly increased (p≤0.01) after fusion, except for the cobalt-chrome conditions in extension (p≥0.06), and no significant differences (p>0.99) were found among fixation constructs. Energy loss, differences became significant between the cobalt-chrome with transverse connector condition with respect to the cobalt-chrome (p=0.05) and titanium (p
There is not enough evidence to support that the cobalt-chrome rods performed biomechanically different than the titanium rods. The use of titanium rods may be more beneficial because there is a lower probability of corrosion. The inclusion of the transverse connector only increased stability for the cobalt-chromium construct in axial rotation, which suggests that it is beneficial in complete facetectomy procedures.
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Wettstein, Reto. "The effect of pedicle artery vasospasm on microhemodynamics in anatomically perfused and extended skin flap tissue /." [S.l.] : [s.n.], 2000. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Miyata, Masahiko. "Rheumatoid arthritis as a risk factor for an atlantoaxial transarticular screw and a C2 pedicle screw." Kyoto University, 2009. http://hdl.handle.net/2433/124336.
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Baaj, AliA, Kamran Sattarov, Jesse Skoch, Salman Abbasifard, AparS Patel, MauricioJ Avila, and ChristinaM Walter. "Posterior atlantoaxial fixation: A cadaveric and fluoroscopic step-by-step technical guide." MedKnow, 2015. http://hdl.handle.net/10150/621332.
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UA Open Access Publishing FundBackground: Atlantoaxial surgical fixation is widely employed treatment strategy for a myriad of pathologies affecting the stability of the atlantoaxial joint. The most common technique used in adults, and in certain cases in children, involves a posterior construct with C1 lateral mass screws, and C2 pars or pedicle screws. This technical note aims to provide a step‑by‑step guide to this procedure using cadaveric and fluoroscopic images. Methods: An embalmed, human, cadaveric, specimen was used for this study. The subject did not have obvious occipital‑cervical pathology. Dissections and techniques were performed to mimic actual surgical technique. Photographs were taken during each step, and the critical aspects of each step were highlighted. Fluoroscopic images from a real patient undergoing C1/C2 fixation were also utilized to further highlight the anatomic‑radiographic relationships. This study was performed without external or industry funding. Results: Photographic and radiographic pictures and drawings are presented to illustrate the pertinent anatomy and technical aspects of this technique. The nuances of each step, including complication avoidance strategies are also highlighted. Conclusions: Given the widespread utilization of this technique, described step‑by‑step guide is timely for surgeons and trainees alike.
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Abrahão, Fernando Alexandre. "Estudo da influência da técnica de preparação dos pedículos vertebrais na resistência ao arrancamento dos implantes." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-12022016-154421/.
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Foi realizado estudo experimental, utilizando-se vértebra de suínos, para o estudo da influência da técnica de perfuração do pedículo vertebral na resistência ao arrancamento dos implantes. A técnica de perfuração com broca seguida de macheamento do canal pedicular (técnica 1) foi individualmente comparada com as demais: perfuração com broca sem macheamento do canal pedicular (técnica 2), perfuração com fio de Kirschner com macheamento do canal pedicular (técnica 3), perfuração com sonda sem macheamento do canal pedicular (técnica 4). Três grupos experimentais foram utilizados de acordo com a preparação do orifício. O grupo I comparou a técnica 1 com a técnica 2, no qual foi estudado a influência do macheamento no canal do pedículo. O grupo II comparou a técnica 1 com a técnica 3, no qual foi estudado a influência no modo de preparo do orifício utilizando fio de Kirschner. O grupo III comparou a técnica 1 com a técnica 4, no qual foi estudado a influência da utilização da sonda no preparo do orifício. O resultados da comparação da técnica. de perfuração do orifício de acordo com os parâmetros estudados (carga máxima de arrancamento, rigidez, carga no limite de proporcionalidade, deslocamento máximo e deslocamento no limite de proporcionalidade), mostraram que não houve diferença estatisticamente significante entre as diferentes técnicas utilizadas para o preparo dos orifícios do pedículo vertebral na resistência ao arrancamento dos implantes.An experimental study was conducted on swme vertebrae to investigate the effect of the technique of vertebral pedicle perforation on the pullout resistance of the implants. The technique of perforation with a burr followed by tapping of the pedicular canal (technique 1) was individually compared to the remaining ones, i.e., perforation with a burr without tapping of the pedicular canal (technique 2), perforation with a Kirschner wire with tapping of the pedicular canal (technique 3), and perforation with a probe without tapping of the pedicular canal (technique 4). Three experimental groups were used according to orifice preparation. Group I was used to compare technique 1 to technique 2, with a study of the effect of tapping on the pedicular canal. Group II was used to compare technique 1 with technique 3, with a study of the effect of mode of orifice preparation using a Kirschner wire. Group III was used to compare technique 1 to technique 4, with a study of the effect of the use of a probe for orifice preparation. Comparison of the techniques of orifice preparation according to the parameters studied (maximum pullout load, stiffness, load in the proportionality limit, maximum dislocation, and dislocation in the proportionality limit) showed no statistically significant difference between the various techniques used for preparation of the orifices of the vertebral pedicle, in terms of their effect on the pullout resistance of the implants.
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Hasegawa, Yukiharu, Shuhei Torii, Seiki Iwasada, Shinji Kitamura, Toshikazu Kubo, and Hisashi Iwata. "Pedicle Bone Grafting versus Transtrochanteric Rotational Osteotomyfor Idiopathic Osteonecrosis of the Femoral Head : Four Patients withBoth Procedures." 名古屋大学医学部, 1999. http://hdl.handle.net/2237/6206.
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Schick, Joanne Louise. "Stress physiology of pedicel browning in sweet cherries." Thesis, 2001. http://hdl.handle.net/2429/11446.
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The overall objective of this research was to investigate the influence of some physiological
stress factors on postharvest pedicel browning in sweet cherry (Prunus avium L.). While the
research focused on examining the effects of stresses on stem quality; decay, pitting and soluble
solids content (SSC) in the fruit were also monitored. Because PPO is a major enzyme involved in
browning, PPO activity under the influence of some stress factors was also examined.
Recommendations aimed at improving commercial sweet cherry quality were made as a result of this
work.
The use of a reflective tarp was assessed for its potential to improve quality retention of sweet
cherries. The tarp was applied as cover to bins of harvested cherries in the orchard and also during
open-truck transport to the packing house. Controls were bins that were left uncovered in the
orchard and during transport. The results show that reflective tarps, applied with a white painted
side facing the sun and the shiny metallic surface next to the cherries, reduced pedicel browning,
fruit decay and pitting, when cherries were stored in modified atmosphere packages (MAP) for
several weeks.
Reflective tarps helped to retain cherry pedicel quality through modification of temperature
and relative humidity (RH). Fruit that was covered remained up to 5 °C cooler than fruit that was
uncovered and the RH in the immediate air space surrounding the fruit was increased by 15-20%.
Under these modified conditions the pedicels of covered fruit retained more water than those that
were uncovered. UV-absorbing substances leaking from pedicel tissue was measured. From this
inferences were made regarding damage to pedicel cellular membranes. RLR always negatively
correlated with pedicel browning (R = -0.92, P ≤ 0.01). This indicated that browning was related
to some structural damage to the plant tissue.
The effects of temperature, RH and light on pedicel browning were examined separately in
several laboratory experiments. RH had the single largest effect on pedicel browning. As RH
decreased, browning increased. Higher temperatures also resulted in more pedicel browning.
Radiation from metal halide lamps and fluorescent bulbs had no effect on pedicel browning.
The effect of postharvest handling at 0 °C, 10 °C, 20 °C and 30 °C on 'Van', 'Bing' and
'Lapins' cherry pedicels was investigated at two stages of maturity. 'Van'pedicels were more
resistant to browning than 'Bing' or 'Lapins' pedicels regardless of temperature or maturity.
'Lapins' pedicels showed the highest amount of bruising. Less browning occurred in more mature
'Lapins' and 'Bing'pedicels than in less mature 'Lapins' and 'Bing' pedicels. Cherries that are
harvested too early may be more susceptible to handling injury. Cherry pedicels were most
susceptible to bruising at 30 °C and least susceptible at 10 °C. These results suggest that optimum
harvest time for 'Lapins' and 'Bing' for pedicel quality was at the mahogany maturity stage and the
best handling temperature was 10 °C.
Preharvest water stress had no effect on pedicel browning. Cherry trees were stressed by
withholding water for four weeks and two weeks before harvest. Controls were cherries from trees
that were watered weekly. Overall soil moisture content and pressure bomb readings indicated that
the water stressed trees were without sufficient irrigation. Withholding water for up to four weeks
before harvest did not result in higher rates of pedicel browning.
Some properties of cherry pedicel polyphenol oxidase (PPO) were examined by kinetic
analysis and electrophoresis. PPO activity did not correlate with pedicel browning. The optimum
pH for PPO activity was 5.5. Two PPO isozymes were isolated from 'Lambert' and 'Lapins'
pedicels by SDS-PAGE on 4-15% gradient gels under partially denaturing conditions. A smaller,
more intense band with an apparent molecular weight of 43.5 kD and a less intense larger band with
apparent molecular weight of 37.5 kD, were isolated from both brown and green 'Lambert' and
'Lapins' pedicels. More PPO was expressed in the pedicels of 'Lapins' than those of 'Lambert'.
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Mokwatlo, Peter Noko. "Patient satisfaction in breast reduction using the medal pedicle technique versus the inferior pedicle technique." Thesis, 2018. https://hdl.handle.net/10539/29127.
Full textAbstract:
A dissertation submitted to the Faculty of Health Sciences, University of
the Witwatersrand, Johannesburg, in partial fulfillment of the
requirements for the degree of Master of Medicine in Plastic and
Reconstructive Surgery.
Johannesburg, 2018Background: Breast reduction surgery is an accepted and commonly performed procedure for addressing gigantomastia for cosmetic and functional purposes. It has been proven to have a high rate of patient satisfaction. It is a functional operation, improving quality of life in symptomatic patients. Aims: This study evaluated patients’ satisfaction in subjects who had undergone breast reduction surgery between June 2017 and June 2018 at Chris Hani Baragwanath Academic Hospital (CHBAH), Helen Joseph Academic Hospital (HJAH) and Netcare Rand Clinic, using the medial pedicle technique versus the inferior pedicle technique. Methods: Patient satisfaction was evaluated by assessing the following domains, satisfaction with breasts, satisfaction with nipples, satisfaction with outcome, psychosocial well-being, sexual well-being, physical well-being. The BREAST-Q questionnaire is a measuring tool employed to evaluate patient satisfaction secondary to breast reduction that meets international and federal standards. A total of 30 patients completed the BREAST-Q questionnaire in the clinics as they came for their follow-ups post-surgery. Fifteen participants had undergone breast reduction through the medial pedicle technique whilst the other 15 had had the procedure performed using the inferior pedicle technique. Results: The pedicles used were medial (n =15) and inferior (n =15). The findings were; breast satisfaction: medial pedicle technique 68.9 ± 17.6, inferior pedicle technique 69.6 ± 18.7 with a p-value of 0.926. Physical wellbeing: medial pedicle technique 62.7 ± 19.6, inferior pedicle technique 84.2 ± 14.2 with a p-value of 0.002. The two techniques performed equally on average and in all the domains except in the physical wellbeing domain where the inferior pedicle technique had a statistically significant superiority to the medial pedicle technique. Conclusions: The use of different techniques in breast reduction will continue. Through the use of tools like the BREAST-Q questionnaire in patient related outcome measurements, we will gain a window into the patients’ feeling about the different techniques and in the process learn or change to techniques that offer better patient satisfaction. The resected breast tissue should have been weighed at the time of operation. Symptom relief is based on the volume of tissue resected.
MT 2020
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Jun-XiangPeng and 彭俊翔. "Analysis of Anatomical Location of Lumbar Pedicle and Security of Pedicle Screw Insertion Using Medical Images." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/46852m.
Full textAbstract:
碩士國立成功大學
土木工程學系
104
Pedicle screw fixation is a difficult and dangerous surgery, because the pedicle is irregular in shape and narrow in its diameter. In order to insert the screw correctly, the doctor must be very experienced and skillful. At present, this surgery still be operated in traditional way in Taiwan, it means that the doctor insert the screw by their experience. There are central nervous system and vein close to the pedicle. Once pedicle screw is inserted inappropriate and penetrates the cortical bone, it may cause damage to the nerve or vein, and it should be treated as soon as possible to prevent the complication. Therefore, this is an important topic that how to judge the condition of pedicle screw insertion. In this study, we collect the sizes, angles and locations of pedicle and pedicle screw by use of the measurement in medical images and two formulas which is used to obtain the rotation angle of vertebrae (θ) and transverse screw angle (TSA). After that, we simply simulate the pedicle by elliptic cylinder and screw by cylinder in MATLAB, and place these two objects based on the information we collected, then we will get the three dimensional simulate result of pedicle screw insertion. The results from the analysis on real case show that mean absolute error of θ is 2.1 degrees and the mean absolute error of TSA is 3.5 degrees. And the trend of simulation is the same as real images. Therefore, we believe that it works for the postoperative inspection by this simulation method.
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Liu, Yo-ming, and 劉又銘. "Spine pedicle path locate error assessment and spine pedicle path planning in C-arm navigation system." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/47099665573579155103.
Full textAbstract:
碩士國立中央大學
生物醫學工程研究所
99
C-arm image assisted navigation system for orthopedic surgery has been applied clinically for several years. Pedicle screw implantation is one of the important applications. However, positioning accuracy is still lack of quantification analysis. Also, the implantation direction on the Anterior/Posterior-view image is difficult to plan. Therefore, in this research, we analyze and improve positioning errors of the C-arm assisted navigation system developed by our laboratory and establish a path planning reference on the AP image based on Digitally Reconstructed Radiographs of CT images. Three methods are applied to verify positioning errors. One is to calculate the position errors of calculated AP-View and LA-View images with the real image of the surgical instrument. Two is to calculate the errors of the inversely projected spatial position according to the AP-View image and LA-View image of the surgical instrument with its measured spatial position. Three is to define a safe zone and evaluate whether the instrument is within the zone. The experimental results show that the main factor of positioning error is due to respiration of the patient, which causes the asynchronous catch of C-arm images and the corresponding coordinates of the X-ray source. On the other hand, the new or used reflective balls only have minor effect in measuring the DRF coordinates. As to surgical path planning, the path is planned on the reconstructed 3D CT model. Then, it is projected onto so-called AP-view through Digitally Reconstructed Radiographs algorithm. The projected paths are defined according to the feature points of the spine. The average location of the paths is the reference to plan surgical path on the AP-view, which might reduce the uncertainty of path planning and promote success rate of operation.
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許珍禎. "Characterization of genes involving development of abscission zone in tomato flower pedicel." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/38694298489670105575.
Full textAbstract:
碩士國立嘉義大學
農業生物技術研究所
95
Abstract Abscission is a catabolic cell wall process that leads to the shedding of a plant organ. This process is regulated by biotic and abiotic cues. Manipulating occurrence of abscission is commercially important, for premature abscission is a major cause for low yield production for certain crops. For the majority of dicotyledon plants, abscission is initiated by the plant hormone ethylene. The hormone is perceived very specific cell within the abscission zone which has been proposed to be a class of target cells for ethylene. Hence understanding the regulatory network for abscission zone development is an important step toward effective control of plant abscission. Tomato JOINTLESS gene controls abscission zone formation in flower pedicel. This gene has been identified by map-based cloning to be a new member of MADS-box gene family. In an attempt to gain more understand in the transcriptional regulatory network for abscission zone development, we conducted cDNA-AFLP to compare the transcription profiling of wild-type and jointless mutant. We have analyzed about 16,053 transcript- derived fragments (TDFs). Among them, 1,258 cDNAs exhibit differential expression between LA3021 and LA3023 cDNA. DNA dot blot was used to confirm 239 cDNAs for differential expression. Sequence analysis of differential expressed cDNA reveal features of photosynthesis-related, DNA or RNA binding, cell structure, protein kinase, metabolism, transporters, hormone, protein degradation, protein trafficking, transcription factors and GTP-binding proteins. Northern blot analysis confirmed that genes of protein kinase, cell division, protein trafficking and transcription factor were differentially expressed in the wild-type and jointless mutant. Among them, differential expressed genes confirmed by northern blot are correlated to protein kinase, cell division, protein trafficking, transcription factors and GTP-binding proteins. This result demonstrates that a complex signal pathway is involved in the differentiation of abscission zoon in tomato flower pedicels.
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Su, Chung-wei, and 蘇崇瑋. "Optimization analysis of strenthening invasive pedicle screw." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/74164285715806385906.
Full textAbstract:
碩士國立中央大學
機械工程研究所
100
In this aging society, spinal disease becomes one of the common human civilization diseases. Pedicle screw is a fundamental part used in spinal surgery. We lock pedicle screw into the vertebrae to provide a fixed force to offer the stability of the human spine. With the development of the invasive spine surgery, traditional pedicle screw is replaced by cannular pedicle screw in order to be used in surgery with guide pin. In this study, firstly, we use the finite elements analysis method to compare the two models’ (tradional and cannular) difference in stress. Secondly, we put the same material (Ti6Al4V) of pin into the cannular pedicle screw to expect increasing pedicle screw’s intensity. And compare these three pedicle screws’ (traditional, cannular and cannular with pin) intensity in stress. In addition, we use Taguchi method to do the optimization aimed at cannular pedicle screw with pin. The four factors include five levels of pedicle screw diameter, three levels of cannular diameter, three levels of clearance between pin and cannular pedicle screw and three levels of pin length. Explore the contribution of each factor for pedicle screw’s stress and find out the best model. At last, making the best model, and comparing it with other models to check the Taguchi method we use is correct. At the last, consulting the reference to construct a mathematical model of bending strength of invasive pedicle screw, and compare its stress value with value of FEM. If it shows the positive correlation, we can use this model to calculate stress value before FEM to save analysis time in the fusture.
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Chen, Yi-Long, and 陳怡龍. "The biomechanical behaviors analysis of minimally invasive percutanuous cannulated pedicle screw and cannulated-fenestrated pedicle screws in osteoporotic vertebral body." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/15896502000667477117.
Full textAbstract:
博士國立陽明大學
生物醫學工程學系
104
Pedicle screws fixation has become one of the standard operations in lumbar spine fusion. It has been used in treatment of various diseases of lumbar spine to reestablish spinal stability. Pedicle screws fixation is considered the most stable one among posterior fixation devices. However, when it apply to patients with osteoporosis, the effect of pedicle screws fixation significantly decreased, and the risk of failure significantly increased. Many methods had been tried to resolve the problem, such as laminar hooks, sublaminar wiring and reinforce with bone cement. Recently, various kinds of cannulated-fenestrated pedicle screws were designed. After insertion of the screws, bone cement can be injected through the central canal and the side holes, filling between trabecular bone of vertebral body and the screw. Therefore, the screw bone interface can be reinforced. Although widely used, the problem of the structural weakness of the cannulated-fenestrated pedicle screws should be concerned. To overcome the pressure in vertebral body and the viscosity of bone cement, some products with larger central canal and side holes were designed. These products make it easier to inject bone cement at the cost of the structural strength of the screws. There were some cases with failure of the cannulated-fenestrated screws observed in clinical practice. To our knowledge, there is no study aiming to define the ideal central canal diameter and ideal number of side holes. Therefore, we designed a biomechanical experiment and finite element analysis, trying to find out the ideal central canal diameter and the ideal number of side holes to minimize the risk of screw failure. The result of the experiment showed that the risk of screw failure enlarged with the number of side holes. Besides, the stress increased with the enlargement of the central canal. We recommend limit the number of side hole to four and the diameter of the central canal between 1.5-2.0mm.
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Hsia, Shen, and 夏笙. "CT-based navigation system for pedicle screw insertion." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/02483292586551178644.
Full text
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Chetty, Vaneshri. "The safety of the superomedial pedicle for gigantomastia." Thesis, 2016. http://hdl.handle.net/10539/22464.
Full textAbstract:
A research submitted to the Faculty of Health Sciences, University of Witwatersrand,
Johannesburg, in partial fulfillment of the requirements for the degree of Master of
Medicine in Plastic and Reconstructive Surgery
18 July 2016
JohannesburgIntroduction Breast reduction surgery in women with gigantomastia and macromastia can present as a major challenge to the plastic and reconstructive surgeon. The superomedial pedicle (SMP) technique of breast reduction has been shown to be a safe and efficacious procedure to decrease a moderate size hypertrophy of the mammary glands. A myriad of techniques has been demonstrated to decrease the size of extremely large and hyperplastic breasts, they can, however, potentially result in complications, amongst the most dreaded being damage to the nipple-areola complex (NAC), especially necrosis and loss of sensibility. Excessive breast hypertrophy is termed macromastia or gigantomastia. Macromastia is defined as an excess or hypertrophy of breast tissue over 1.0 kg per breast but less than 2.0 kg. Gigantomastia is defined as hypertrophied breast tissue equal to and greater than 2.0 kg per breast. [1] McKissock recommended breast amputation mammoplasty and free nipple grafts for those reductions that required removal of more than one kilogram of parenchyma, or if the length of vertical distance is greater than 35 cm. [2] Numerous pedicled techniques of breast reduction exist and pedicles can be based in any of the four quadrants as well as centrally. While the 2 main skin excision patterns include the Wise pattern (inverted T-shape closure) and the Vertical pattern. (Diagram.1 & 2) Objective The objective of this study was to determine exactly how efficiently the superomedial pedicle (SMP) technique performs breast reduction surgery, particularly in candidates with extremely large breasts, viz. macromastia and gigantomastia. To evaluate the efficacy and complication rate of the SMP reduction mammoplasty technique, with wise pattern skin closure, for macromastia and gigantomastic breasts, at two different hospitals in Johannesburg, as performed by 2 surgeons, Chetty, V. and Ndobe, E. Methods Retrospective review of patient records with macromastia and gigantomastia who had undergone the SMP technique reduction mammoplasty, over a 4-year period. Complications were assessed at 1 week, 3 weeks, 6 months and a mean of one-year post operatively. Photo records were taken at each stage. Results There were a total of 31 patients, 62 breasts, with macromastia and gigantomastia that had an SMP pattern of reduction. The mean age was 30.1 years, mean BMI was 28.1 and average resection weight from each breast was 1835 g. The mean N-N was 44.13 cm. The majority, 90 % of patients had a good aesthetic outcome with less than 20% having any long-term complications, which were all relatively minor. Conclusion The SMP reduction mammoplasty efficiently reduces extremely large breasts while preserving the integrity of the NAC, sensation and simultaneously provides a wellshaped, projecting breast in macromastia and gigantomastia patients.
MT2017
50
Lin, Zheng-wei, and 林政瑋. "Improved Pedicle Screw Design for Osteoporotic Spine Fixation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/83830402310261625184.
Full textAbstract:
碩士國立成功大學
醫學工程研究所碩博士班
96
Spine support body axis and provide active function. For the patients who lost spinal stability because of pathologic disease treated by pedicle screw to reduction and correction in clinical. For the osteoporotic patients, it was difficult to treat in stable effect due to lack of enough strength between pedicle screw and cancellous bone. The purpose of this research was to improve the structure of the normal pedicle screw for osteoporotic spine to increase the stability of pedicle screw and prevent loosening . Finite element method was used to analyze the biomechanical behavior with normal pedicle screw and improved pedicle screw combined bone cement into osteoporotic spine. In addition, stresses distribution of stainless steel 316L and titanium Ti-6Al-4V after simulation was investigated by using material yielding strength and literatures to compare the results. The analytical results illustrate that (1) the strength of improved pedicle screw is the same as normal pedicle screw, (2)improved pedicle screw has few stress concentration at corner of seepage hole, it reduce after adding bone cement into screw and cover all of seepage hole. But stress raise at cancellous bone with contact region of cement, (3)pull-out testing discover no difference of screw’s deformation, because of applying pull-out force too high, it exceeds pull-out strength of osteoporotic vertebra, the pedicle screw is failure by flexion loading. Future works suggest that (1)take osteoporotic vertebra to build 3D model in clinical, it will has more accurate results, (2) to proceed experiment by osteoporotic vertebra to verify finite element simulate results.