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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Efeito da atividade física aeróbica programada sobre a pressão arterial, expressão da via NFkB e da HSP 70 em ratos espontaneamente hipertensos = Effect of physical activity program in aerobic blood pressure and expression in NFkB pathway and HSP 70 in spontaneously hypertensive rats / Effect of physical activity program in aerobic blood pressure and expression in NFkB pathway and HSP 70 in spontaneously hypertensive rats

Silva, Vinícius Rodrigues, 1982- 21 August 2018 (has links)
Orientador: José Antônio Rocha Gontijo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T14:33:21Z (GMT). No. of bitstreams: 1 Silva_ViniciusRodrigues_M.pdf: 1936844 bytes, checksum: f004702604f1152c92bafb324a7d141d (MD5) Previous issue date: 2012 / Resumo: O treinamento físico progressivo deve ser considerado uma escolha terapêutica valiosa em portadores de doenças cardiovasculares, incluindo hipertensão arterial. Assim sendo o objetivo deste trabalho foi averiguar os efeitos da atividade física programada, com diferentes intensidades e duração do treinamento, sobre a pressão arterial sistêmica, o manuseio tubular renal de sódio e filtração glomerular, a manipulação renal de sódio e a expressão de proteínas da via inflamatório: TNF-R1, p-I?B, NF?B e a proteína do choque térmico HSP-70 em tecido renal e ventricular esquerdo de ratos espontaneamente hipertensos (SHR) e Wistar Kyoto (WKY) Métodos: Os ratos de ambas as linhagens realizaram atividade física em meio aquoso termoneutro, sendo as duas primeiras semanas compostas por treinamento adaptivo à água e as 4 semanas seguinte compostas por treinamento incremental utilizando chumbo como peso extracorpóreo. Foram semanalmente mensurados o peso corporal e lactato sanguíneo (reação de colorimetria) em ambas as linhagens e em todos os grupos experimentais, após 4 e 6 semanas de treinamento foram analisadas a função renal (mensuração de creatinina, sódio, lítio e potássio), ensaio da atividade da citrato síntese (reação de colorimetrial), determinação da hipertrofia cardíaca (determinação do índice de hipertrofia cardíaca), análise dos valores de pressão arterial sistêmica (pletismografia) western blot de tecido renal e ventricular esquerdo e imunohistoquímica de tecido renal. Os dados foram analisados utilizando teste ANOVA para análise dos valores de massa corporal e teste t student para as demais variáveis. Resultados: Os dados de lactato sanguíneo não ultrapassaram 5,5 mmol/L em nenhuma semana de treinamento em ambas as linhagens caracterizando treinamento de predominância aeróbia, os valores de lactato sanguíneo comprovaram a eficiência do exercício físico propostos sendo maiores nos grupos treinados de ambas as linhas pós 6 semanas de treinamento, o estudo mostraram também que a pressão arterial foi reduzida significativamente em ratos SHRT vs. SHRS após 4 e 6 semanas de treinamento 180, 6 '+ ou -' 4,3 mmHg em SHRS para 126,2 '+ ou -' 2,2 mmHg em SHRT (P <0,05). Além disso, os dados da filtração glomerular bem como o manuseio tubular renal de sódio nos apontam um aumento da excreção de sódio urinário em ratos fracionada SHRT de 0,2 '+ ou -' 0,07-, 8 '+ ou -' 0,03% (P <0, 001) em comparação com SHRS, apesar de uma depuração da creatinina inalterada. Este FENa aumentou consistentemente em SHRT foi acompanhado por um aumento significativo da excreção de sódio proximal e pós-proximal (de 4,0 '+ ou -' 0,9-2,3 '+ ou -' 0,9%, respectivamente (P <0,01). Esta excreção de sódio melhorada fracionada no longo prazo SHR foi treinada seguida por um aumento significativo na FEK de 0,2 '+ ou -' 0,03-0,5 '+ ou -' 0,02%, quando comparado com animais de SHRs (P <0,009), com relação aos dados referentes à via inflamatória, observamos menor expressão de NF?B em ratos SHRT vs. SHRS após 4 semanas de treinamento e uma tendência à manutenção dessa menor expressão após 6 semanas, além de verificarmos uma expressão significativa maior em SHRT vs. SHRS de HSP 70 após a sexta semana de treinamento. Conclusão: O presente estudo pode indicar que, no rim, em longo prazo de exercício exerce um efeito modulador sobre tubular excreção de sódio. Na verdade, o estudo indica uma associação de natriurese aumentar com a queda nos níveis de pressão arterial, observadas em SHRT, em comparação com ratos de mesma faixa etária SHRS, além de promover aumento da expressão de HSP 70 e uma tendência a diminuição do processo inflamatório / Abstract: Aims: Progressive exercise training should be considered a valuable therapeutic choice in cardiovascular disease including arterial hypertension. Since the long-term changes in renal sodium tubule handling are associated with SHR hypertensive development, we hypothesize that aerobic exercise (plasma lactate levels smaller than 5.5 mmol/L/100 g body mass) and increased citrate synthase activity) training may cause an enhancement in urinary sodium excretion associated with blood pressure fall in conscious, trained Okamoto-Aoki rats (SHRT) compared with appropriate age-matched sedentary SHR (SHRS). To test this hypothesis, we study the tubular sodium handling, evaluated by lithium clearance, in conscious SHRT, compared with their appropriate controls (SHRS). Methods: To evaluate the influence of exercise training compared with sedentary rats on estimate renal function we used creatinine and lithium clearance methods. The exercise training was carried out according to a protocol consisting of graded swim-training exercises, with progressive increments of overload using weights attached to the animals' tails. Data obtained over time were analyzed using appropriate ANOVA and Student t test. Results: Regarding the effects of long-term aerobic, the current study demonstrated that increased blood pressure in SHR was blunted and significantly reduced by long-term swim training between the ages of 6-wks and 12-wks old from systolic blood pressure averaged 150,6'+ or -' 4,3 mmHg in SHRS to 126,2'+ or -'2,2 mmHg in SHRT (P<0,05). Additionally, the investigation observed an increased fractional urinary sodium excretion in SHRT rats from 0.2 '+ or -' 0.07 to 0.8 '+ or -' 0.03% (P<0.001) compared to SHRS, despite a unchanged creatinine clearance. This consistently increased FENa in SHRT was accompanied by a significant enhancement in proximal and post-proximal sodium excretion (from 4.0 '+ or -' 0.9 to 2.3 '+ or -' 0.9 %, respectively (P<0.01).This enhanced fractional sodium excretion in long-term trained SHR was followed by a significant increase in FEK from 0.2 '+ or -' 0.03 to 0.5 '+ or -' 0.02% when compared with SHRS animals (P<0.009). Conclusion: The present study may indicate that, in the kidney, long-term exercise exerts a modulating effect on tubular sodium excretion with unchanged glomerular filtration rate. In fact, the present study indicates an association of increasing natriuresis with the fall in blood pressure levels observed in SHRT, compared with age-matched SHRS rats / Mestrado / Fisiopatologia Médica / Mestre em Ciências
102

Avaliação da modulação autonômica cardiovascular de camundongos diabéticos não obesos

Moraes, Oscar Albuquerque de 10 December 2013 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2015-07-27T13:30:56Z No. of bitstreams: 1 Oscar Albuquerque de Moraes.pdf: 5700519 bytes, checksum: 9bc35ce1df2c3e4a35600d5a4b8579a6 (MD5) / Made available in DSpace on 2015-07-27T13:30:56Z (GMT). No. of bitstreams: 1 Oscar Albuquerque de Moraes.pdf: 5700519 bytes, checksum: 9bc35ce1df2c3e4a35600d5a4b8579a6 (MD5) Previous issue date: 2013-12-10 / Introduction: It is known that diabetes is associated with autonomic dysfunction and this is a severe complication that increases the risk of cardiovascular mortality. The non-obese diabetic mice (NOD) is an experimental model of type 1 diabetes which develops insulitis at the 4th week and diabetes between the 14th and the 20th week of life. However, data about autonomic function in these mice remain scarce. Objective: To investigate the cardiovascular autonomic profile of NOD mice. Methods: Female mice (24-28 week old) were divided in two groups: NOD (n=6) and control (n=6, swiss mice). NOD mice with glycemia ≥300 mg/dl were used in this study. Heart rate variability (HRV) was evaluated in time and frequency domains and also through symbolic analysis. Were also analyzed the variability of the blood pressure, and baroreflex sensitivity by means of the bradycardic and tachycardic responses induced by infusion of phenylephrine and sodium nitroprusside. Student t test for independent samples and Pearson's correlation coefficient were used for statistical analyses. The data were described as means and standard error. Results: The heart rate and arterial pressure were similar between the groups, however HRV (total variance of RR interval: NOD = 21.07 ± 3.75 vs. C = 42.02 ± 6.54 ms2) and RMSSD (NOD = 4.01 ± 0.32 vs. C = 8.28 ± 0.97 ms), a vagal modulation index, were lower in NOD group when compared to control group. Moreover, the low frequency component was higher in NOD group (normalized LF: NOD = 61.0 ± 4.0 vs. C = 20.0 ± 4.0%), while the high frequency of HR component was lower in NOD compared with the control group (normalized HF: NOD = 39.0 ± 4.0% vs. C = 80.0 ± 4.0%). Similarly, the 0V pattern of symbolic analysis, indicative of sympathetic activity, was increased in NOD group when compared to the control group (NOD = 11.9 ± 1.4 vs. C = 6.06 ± 0.90%) and the 2LV pattern, indicative of parasympathetic activity, was reduced in the NOD group (NOD = 7.98 ± 1.3 vs. C = 21.2 ± 3.36%). Both responses to arterial pressure changes, tachycardic (NOD = 3.01 ± 0.72 vs. C = 4.54 ± 0.36 bpm/mmHg) and bradycardic (NOD = 2.49 ± 0.31 vs. C = 3.43 ± 0.33 bpm/mmHg) were lower in NOD when compared to the control group. A negative correlation between the indices of vagal modulation (RMSSD, normalized high frequency component and 2LV pattern of symbolic analysis) and blood glucose levels was also observed. Conclusions: The NOD mice present cardiovascular autonomic dysfunction and that is probably associated with glycemic levels. / Introdução: O diabetes está associado com disfunção autonômica e esta é uma grave complicação que eleva o risco de mortalidade cardiovascular. O camundongo não obeso diabético (NOD) é um modelo experimental de diabetes tipo 1 que desenvolve insulinite na quarta semana de vida e diabetes entre a 14ª e 20ª semana de vida. Contudo, dados sobre a função autonômica cardiovascular em camundongos NOD permanecem escassos. Objetivos: Investigar a função autonômica cardiovascular do camundongo NOD. Métodos: Camundongos fêmeas (24-28 semanas de vida) foram divididas em dois grupos: NOD (n = 6) e controle (C, camundongo suiço, n=6). Foram incluídos no grupo NOD animais com glicemia igual ou superior a 300 mg/dl. Foi avaliada a variabilidade da frequência cardíaca no domínio do tempo e da frequência e também por meio de análise simbólica. Além disso, foram avaliados a variabilidade da pressão arterial, bem como a sensibilidade barorreflexa, por meio das respostas bradicárdicas e taquicárdicas induzidas pela infusão de fenilefrina e nitroprussiato de sódio. Para análise estatística foi utilizado o teste t de Student para amostras independentes e o coeficiente de correlação de Pearson. Os dados foram descritos como média e erro padrão. Resultados: A frequência cardíaca e a pressão arterial foram similares entre os grupos, no entanto a variabilidade da frequência cardíaca (variância do intervalo de pulso: NOD = 21,07 ± 3,75 vs. C = 42,02 ± 6,54 ms2) e o RMSSD (NOD = 4,01 ± 0,32 vs. C = 8,28 ± 0,97 ms), um índice de modulação vagal, foram menores no grupo NOD quando comparados ao grupo controle. Além disso, o componente de baixa frequência foi maior no grupo NOD (BF normalizado: NOD = 61,0 ± 4,0 vs. C = 20,0 ± 4,0%), enquanto que o componente de alta frequência foi menor no grupo NOD quando comparado com o grupo controle (AF normalizado: NOD = 39,0 ± 4,0% vs. C = 80,0 ± 4,0%). De forma semelhante, na análise simbólica o padrão 0V, indicativo da atividade simpática, estava aumentado no grupo NOD em comparação com o grupo controle (NOD= 11,9 ± 1,4 vs. C = 6,06 ± 0,90%) e o padrão 2LV, indicativo da atividade parassimpática, estava reduzido no grupo NOD (NOD = 7,98 ± 1,3 vs. C = 21,2 ± 3,36%). Ambas as respostas reflexas comandadas pelos barorreceptores, taquicárdica (NOD = 3,01 ± 0,72 vs. C = 4,54 ± 0,36 bpm/mmHg) e bradicárdica (NOD = 2,49 ± 0,31 vs. C = 3,43 ± 0,33 bpm/mmHg) foram menores no grupo NOD quando comparadas com o grupo controle. Ainda, observamos uma correlação negativa entre os índices de modulação vagal (RMSSD, componente de alta frequência normalizado e padrão 2LV da análise simbólica) e os níveis glicêmicos. Conclusão: Os camundongos NOD apresentam disfunção autonômica cardiovascular e essa disautonomia está associada com os níveis glicêmicos.
103

Analýza kognitivních funkcí u rekombinantních inbredních kmenů potkanů vzniklých křížením linií SHR a BN Lx / Analysis of cognitive functions in recombinant inbred strains of rats produced by crossbreeding of SHR and BN Lx. lines

Hatalová, Hana January 2011 (has links)
This MSc. thesis deals with dissecting the link between memory, genetics, and metabolic syndrome. Memory is a very complex behavioral trait, probably influenced by innumerable factors. For this experiment HXB/BXH rat recombinant inbred lines (n= 30) and their parental strains (n=2) were used to be trained in the hippocampus dependant spatial learning task called Allothetic Active Place Avoidance. Rats were to memorize sector of a rotating circular arena, which they were to avoid, being motivated by receiving an electric shock upon entering the forbidden sector (4 training sessions; shock sector on the North, 1 retrieval session (no shock), and 3 reversal sessions, to-be-avoided sector facing South; each session 20-min long, retrieval 10-min). Control experiments to exclude impact of motor or sensory abnormalities were run in a form of open-field test and beam-walking test. Correlation with metabolic phenotypes was conducted in an online database of known HXB/BXH phenotypes (GeneNetwork.org). The results showed that differences in learning were significant between the groups (p<0.05); correlation analysis indicated no putative link between selected traits related to metabolic syndrome and memory in rats. The genetic analysis showed a suggestive locus on chromosome 20 for a learning parameter, and...
104

Neuronal Nicotinic Acetylcholine Receptors: Molecular Targets for Alcoholism and Ethanol Reward: A Dissertation

Hendrickson, Linzy M 28 January 2011 (has links)
While it is clear that most drugs of abuse act to increase extracellular dopamine levels in the nucleus accumbens (NAc), the molecular mechanisms mediating this process vary depending on the molecular target each drug acts on. The rewarding properties of most drugs of abuse including cocaine, amphetamine, and heroin have been well established for some time; however, the molecular mechanisms by which ethanol acts to mediate reward have not been fully elucidated. In this thesis, I have examined the role of nicotinic acetylcholine receptors (nAChRs), known molecular targets for nicotine addiction, in mediating the initial rewarding properties of alcohol. Using a mouse model of voluntary ethanol consumption called Drinking in the Dark (DID), in combination with nAChR pharmacology and mouse genetics, we have provided further evidence for the role of nAChRs in mediating the initial rewardingproperties of ethanol. Because of the vast number of possible functional nAChR subtypes present in the brain, I sought to investigate which subtype of nAChR may be responsible for ethanol reinforcement. To accomplish this, I used twocomplementary nAChR mouse models. The first is a knock-out line that does not express the α4 subunit (α4 KO) and the second is a knock-in line that expresses α4* nAChRs that are hypersensitive to agonist (Leu9′Ala). We have also shown, for the first time, that a specific nAChR subtype, those that contain the α4 subunit (α4*), mediate voluntary ethanol consumption and reward. Next, I examined the role of α4* nAChRs in modulating voluntary ethanol consumption after systemic administration of the FDA approved smoking cessation drug varenicline, a partial agonist of α4* nAChRs. We showed that varenicline and nicotine both reduced acute ethanol consumption in an α4* nAChR dependent mechanism. Taken together, our data indicate that activation of α4* nAChRs is necessary and sufficient for reduction of ethanol consumption and further supports the hypothesis that α4* nAChRs are molecular targets for alcohol cessation therapies.
105

Chlorine-induced lung injury and the role of iNOS

Campbell, Holly R., 1976- January 2009 (has links)
No description available.
106

Effect of DNA methyltransferase 1 on transmission ratio distortion and epigenetic inheritance

Yang, Lanjian, 1976- January 2008 (has links)
No description available.
107

The role of retinoic acid receptor gamma in retinoid-induced limb dysmorphogenesis /

Galdones, Eugene. January 2009 (has links)
No description available.
108

Cellular and molecular characterization of inflammation in the injured spinal cord

Ghasemlou, Nader. January 2008 (has links)
No description available.
109

Etude des variations épigénétiques liées aux séquences répétées comme source de changements phénotypiques héritables chez Arabidopsis thaliana

Cortijo, Sandra 10 September 2012 (has links) (PDF)
Des changements de méthylation de l'ADN peuvent affecter l'expression des gènes et pour certains être transmis au travers des générations. De telles " épimutations " qui concernent des groupes de cytosines à proximité ou dans les gènes sont donc une source potentielle de variation phénotypique héritable en absence de changements de la séquence de l'ADN. Chez les plantes la méthylation de l'ADN est cependant principalement observée au niveau des séquences répétées. Il reste à déterminer dans quelle mesure les changements de méthylation au niveau de ce type de séquences peuvent être héritées et affecter les phénotypes. Afin de répondre à ces questions, plus de 500 épiRIL (epigenetic Recombinant Inbred Lines) quasi-isogéniques a été générée chez Arabidopsis thaliana. Cette population a été obtenue par le croisement d'un parent sauvage et d'un parent mutant pour le gène DDM1 présentant une très forte réduction du taux de méthylation de l'ADN. Après un rétrocroisement de la F1 avec une plante sauvage, les individus sauvages pour le gène DDM1 ont été sélectionnés et propagées sur 6 générations par autofécondation. Nous avons montré par l'analyse du méthylome de plus de 100 épiRIL que l'hypométhylation induite par ddm1 présente selon les séquences affectées différents degrés de transmission au travers des générations. La réversion de l'hypométhylation concerne des régions associées à une abondance élevée en sRNA de 24 nt. Nous avons utilisé l'hypométhylation stablement transmise dans les épiRIL induite par ddm1 afin de détecter des QTL (Quantitative Trait Loci) affectant le temps de floraison et la longueur de la racine primaire, deux caractères pour lesquels les variations observées dans les épiRIL présentent une héritabilité importante. En dernier lieu, nous avons recherché par différentes approches les variations causales de ces QTL.
110

Uso de linhagens parcialmente endogâmicas S3 para a produção de híbridos simples de milho. / Use of partly inbred s3 lines for the production of maize single-crosses.

Chavez Cabrera, Alexander 03 December 2001 (has links)
Linhagens endogâmicas (F@1,0) são usualmente utilizadas para a produção de híbridos de milho. Devido a elevada depressão por endogamia no milho, as linhagens endogâmicas apresentam baixa produtividade, encarecendo o custo das sementes de híbridos simples e tornando-os inacessíveis para grande parte dos agricultores dos países em desenvolvimento. Uma alternativa para contornar o problema seria utilizar linhagens parcialmente endogâmicas (0,0 < F < 1,0), selecionadas para capacidade de combinação e uniformidade. Relatos de literatura mostram que (a) híbridos simples de linhagens S3 (F=0,875) devem apresentar performances superiores as de híbridos triplos e duplos de linhagens endogâmicas; (b) a correlação genética entre híbridos simples de linhagens S3 e de linhagens endogâmicas (F@1,0) é elevada (r=0,94); e (c) a produtividade de linhagens S3 é em média 20% superior a de linhagens endogâmicas. Entretanto, a maior dificuldade em se produzir híbridos simples de linhagens parcialmente endogâmicas refere-se à manutenção destas, por apresentarem variabilidade genética. Devido a isto, o objetivo deste estudo foi avaliar a viabilidade de se produzir e utilizar híbridos simples de linhagens parcialmente endogâmicas S3. Para isso, oito linhagens S3 da população BR-105 e dez linhagens da população BR-106, as quais estão alocadas em grupos heteróticos distintos, selecionadas para capacidade de combinação e uniformidade, originais e mantidas por intercruzamentos e seleção moderada por cinco gerações, foram utilizadas. Durante as gerações de manutenção, pelo menos 50 plantas foram usadas. Estas linhagens e cruzamentos destas com dois testadores de grupos heteróticos diferentes, foram avaliados em quatro ambientes no ano agrícola de 1999/2000. Além disso, as linhagens originais e mantidas foram genotipadas utilizando o marcador molecular AFLP para estimar a similaridade genética entre elas. Os resultados obtidos mostraram que, excetuando-se uma linhagem da população BR-105 em que provavelmente ocorreu contaminação, apenas dois caracteres nas linhagens per se e apenas um caráter nos cruzamentos apresentaram alterações positivas e significativas, de treze caracteres avaliados. Entretanto estas alterações são muito pequenas para serem detectadas visualmente. Os resultados das similaridades genéticas entre as linhagens originais e mantidas, mostraram valores elevados, sendo que o limite superior do intervalo de confiança para a maioria das linhagens atingiu o valor 1,0, indicando que a manutenção das linhagens da forma como foi conduzida as suas integridades genéticas foram mantidas. Estes resultados permitiram concluir que seria viável a utilização de linhagens parcialmente endogâmicas S3 para a produção comercial de híbridos simples de milho. / Inbred lines (F@1.0) are usually used for the production of maize single-crosses. Because of the high inbreeding depression in maize, the inbred lines are lower yielding, which causes the seed prices to be costly and then inaccessible for most of the farmers in the developing countries. One way to circumvent the problem would be the use of partly inbred lines (0.0< F<1.0) selected for combining ability and for uniformity within the lines. Reported results have shown that: (a) theoretically, single-crosses from S3 lines (F=0.875) are expected to have superior performance than that of three-way and double-crosses; (b) the genetic correlation of single-crosses from S3 lines and from their inbred lines (F@1.0) counterparts is fairly high (r=0.94); and (c) S3 lines are on the average 20% higher yielding than highly inbred lines. However, the main difficulty in the production of single-cross from partly inbred lines is the maintenance of their genetic integrity because of the variability within them. Therefore, the ob-jective of this research was to study the feasibility of the development and the production of single-crosses from S3 lines. The genetic material included eight original S3 lines from the BR-105 population, and ten original S3 lines from the BR-106 population, selected for combining ability and for uniformity within them, and their counterparts maintained by sib-mating and mild selection for five generations. During the generations of maintenance at least 50 plants per line were used. The populations BR-105 and BR-106 have been assigned to distinct heterotic groups. The original, the maintained lines and their crosses with testers from different heterotic groups were evaluated in four environments in the growing season of 1999/2000. Also, the S3 lines were genotyped with the AFLP molecular marker in order to estimate the genetic similar-ity between the original and their maintained counterparts. The results showed that out of the 13 traits evaluated only two traits in the lines per se, and only one trait in the crosses changed significantly from the original lines to the maintained counterparts. However those changes are too low to be visually detected. The estimates of the genetic similarities between the original and their maintained counterparts S3 lines were high, and the upper bound of the confidence interval for most of the lines reach the limit value, i.e., 1.0. These results showed that the ap-proach uses for the maintenance of the S3 lines was effective and thus the genetic integrity of the lines were maintained. The results of this research could allow one to expect that would be feasible the use of partly inbred S3 lines for the commercial production of maize single-crosses.

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