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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.
541

Modelling the G51D alpha-synuclein Parkinson’s mutation in the rat

Morley, Victoria Lee January 2018 (has links)
Parkinson’s disease (PD) is the second most common neurodegenerative condition to affect humans, and is characterised by the loss of dopaminergic neurons from the substantia nigra pars compacta (SNpc) in the midbrain along with the deposition of abnormal aggregates of alpha-synuclein protein in the brain which are in the form of Lewy bodies. Dopaminergic neurons from the SNpc project into a large subcortical structure known as the striatum, and positron emission tomography (PET) studies have demonstrated the dysfunction of the dopaminergic system in the striatum of patients with PD. Furthermore, immunohistochemistry studies of the striatum have identified the degeneration of dopaminergic nerve terminals and inclusions of alpha-synuclein. An aggressive and early onset form of familial PD is caused by the G51D point mutation in alpha-synuclein (G51D/+). Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) technology has been used to generate a novel and precise rat model of PD which has the G51D mutation in rat alpha-synuclein. Wild-type (WT) and G51D/+ rats were analysed over the course of ageing (5, 10/11 and 16/17 months of age) using histological experiments and L-3,4-dihydroxy-6-18F-fluorophenylalanine (18FDOPA) PET imaging in order to determine if G51D/+ rats have abnormalities of histological staining and dopaminergic function analogous to those identified in patients with PD. Histological experiments were optimised using WT rat tissue and then used immunohistochemistry for tyrosine hydroxylase (an enzyme involved in the synthesis of dopamine) to evaluate dopamine nerve terminal integrity in the striatum of WT and G51D/+ rats. In addition, immunohistochemistry for alpha-synuclein was used to evaluate staining for alpha-synuclein in cell bodies and the neuropil within the striatum of WT and G51D/+ rats. 18F-DOPA is a well validated PET radiotracer and has been used to investigate dopaminergic function in the striatum of rats. The enzyme aromatic L-amino acid decarboxylase converts 18F-DOPA to 6-18F-fluorodopamine, which is in turn incorporated into presynaptic vesicles, and then released into the synaptic cleft following neuronal activation. PET imaging experiments were first optimised using phantoms and WT rats, then the optimised protocols were applied to studies of WT and G51D/+ rats. Results from tyrosine hydroxylase immunohistochemistry at Bregma 0.00 mm identified a trend for decreased optical density of tyrosine hydroxylase staining in the striatum of 5 month G51D/+ rats compared with age-matched WT controls (p=0.15), and in 17 month G51D/+ rats compared with age-matched WT controls (p=0.10). Semi-quantitative analysis of alpha-synuclein immunohistochemistry indicated an increased abundance of alpha-synuclein positive cell somata in the striatum, and decreased punctate terminal staining in the neuropil of G51D/+ rats compared with age-matched WT rats. 18F-DOPA PET imaging experiments indicated a trend for decreased influx rate constant (Ki) of 18F-DOPA in the striatum of 5 month old G51D/+ rats compared with age-matched WT controls (p=0.08), and a trend for decreased distribution volume ratio (DVR) of 18F-DOPA in the striatum relative to the cerebellum of 16 month old G51D/+ rats when compared with age-matched WT controls (p=0.09). 18F-DOPA PET imaging experiments also identified a trend for a decreased effective distribution volume ratio (EDVR) of 18F-DOPA in the striatum relative to the cerebellum (p=0.09) and in turn indicated increased effective dopamine turnover (EDT) (p=0.13) in the striatum of 16 month old G51D/+ rats compared with age-matched WT rats. Therefore, the results indicated abnormalities of dopaminergic function, as well as tyrosine hydroxylase and alpha-synuclein staining in G51D/+ rats compared with age-matched WT controls, and this appeared to have some features of PD in humans. Indices of EDT indicated compensatory changes in dopaminergic function in the striatum of 16 month old G51D/+ rats compared with age-matched WT rats. Additional compensatory changes in dopaminergic terminal function and tyrosine hydroxylase protein expression may be evident in 11 and 10 month old G51D/+ rats respectively compared with age-matched WT rats. The G51D/+ rat model represents an interesting model for further studies such as the underlying pathophysiology of PD. However, the phenotype observed in G51D/+ rats appeared to be less severe than that which has been observed in humans with G51D type PD.
542

Cognitive Changes Across the Menopause Transition: A Longitudinal Evaluation of the Impact of Age and Ovarian Status on Spatial Memory

January 2015 (has links)
abstract: Aging and the menopause transition are both intricately linked to cognitive changes during mid-life and beyond. Clinical literature suggests the age at menopause onset can differentially impact cognitive status later in life. Yet, little is known about the relationship between behavioral and brain changes that occur during the transitional stage into the post-menopausal state. Much of the pre-clinical work evaluating an animal model of menopause involves ovariectomy in rodents; however, ovariectomy results in an abrupt loss of circulating hormones and ovarian tissue, limiting the ability to evaluate gradual follicular depletion. The 4-vinylcyclohexene diepoxide (VCD) model simulates transitional menopause in rodents by selectively depleting the immature ovarian follicle reserve and allowing animals to retain their follicle-deplete ovarian tissue, resulting in a profile similar to the majority of menopausal women. Here, Vehicle or VCD treatment was administered to ovary-intact adult and middle-aged Fischer-344 rats to assess the cognitive effects of transitional menopause via VCD-induced follicular depletion over time, as well as to understand potential interactions with age, with VCD treatment beginning at either six or twelve months of age. Results indicated that subjects that experience menopause onset at a younger age had impaired spatial working memory early in the transition to a follicle-deplete state. Moreover, in the mid- and post- menopause time points, VCD-induced follicular depletion amplified an age effect, whereby Middle-Aged VCD-treated animals had poorer spatial working and reference memory performance than Young VCD-treated animals. Correlations suggested that in middle age, animals with higher circulating estrogen levels tended to perform better on spatial memory tasks. Overall, these findings suggest that the age at menopause onset is a critical parameter to consider when evaluating learning and memory across the transition to reproductive senescence. From a translational perspective, this study informs the field with respect to how the age at menopause onset might impact cognition in menopausal women, as well as provides insight into time points to explore for the window of opportunity for hormone therapy during the menopause transition to attenuate age- and menopause- related cognitive decline, and produce healthy brain aging profiles in women who retain their ovaries throughout the lifespan. / Dissertation/Thesis / Masters Thesis Psychology 2015
543

Transplante de hepatócitos no modelo experimental de hepatotoxicidade aguda induzida por paracetamol em ratos

Rodrigues, Daniela January 2012 (has links)
O transplante de hepatócitos é uma modalidade terapêutica atrativa para as doenças hepáticas, assim como uma alternativa para o transplante hepático. O objetivo do presente estudo é investigar a efetividade do transplante de hepatócitos de ratos nos modelos de hepatotoxicidade aguda induzida por paracetamol (1g/kg e 1,5g/kg). Os hepatócitos foram isolados de ratos Wistar machos e transplantados 24 horas após em receptoras fêmeas com hepatotoxicidade de 1g/kg. Os ratos fêmeas receberam 1x107 hepatócitos (grupo 1, n=20) ou PBS (grupo 2, n=24) através da veia porta ou no baço. A análise de sobrevida em 3 dias demonstrou que todos os animais do grupo 1 sobreviveram, enquanto 5 animais do grupo 2 morreram (P=0,03), todas as mortes ocorreram nos ratos que receberam PBS através da veia porta (P=0,001). Os níveis de alanina aminotransferase e fator V que foram medidos no experimento não mostraram diferença entre o grupo 1 e o grupo 2 em nenhum momento. A análise molecular e a histologia mostraram a presença de hepatócitos no fígado de animais transplantados através da veia porta ou pelo baço. O modelo de hepatotoxicidade aguda induzida por paracetamol (1g/kg) demonstrou que o transplante de hepatócitos de ratos aumenta a sobrevida quando o local de injeção é na veia porta. No modelo de hepatotoxicidade aguda induzida por paracetamol (1,5g/kg), os hepatócitos foram isolados de ratos Wistar machos, e transplantados 6 horas após em receptoras fêmeas. Os ratos fêmeas receberam 1x107 hepatócitos (grupo 1, n=33) ou PBS (grupo 2, n=24) no baço. A análise de sobrevida em 3 dias demonstrou que 9 animais do grupo 1, e 9 animais do grupo 2 morreram no dia 2. Não houve diferença estatística significativa na análise de sobrevida entre o grupo 1 e o grupo 2. Nossos dados demonstram que o isolamento de hepatócitos é um procedimento factível. O transplante de hepatócitos é uma técnica que pode ser aplicada em modelos animais de IHA levando ao aumento da sobrevida. Entretanto, o modelo utilizado no presente estudo apresentou um alto grau de variabilidade, tornando necessária a avaliação do transplante de hepatócitos em um modelo mais reprodutível. / Hepatocyte transplantation is an attractive therapeutic modality for liver disease as an alternative for liver transplantation. The aim of the current study was to investigate the effectiveness of rat hepatocyte transplantation in the acetaminophen-induced acute hepatotoxicity models (1g/kg and 1,5g/kg). Hepatocytes were isolated from male Wistar rats and transplanted 24 hours later in female recipients with hepatotoxicity of 1g/kg of acetaminophen. Female rats received either 1x107 hepatocytes (group1, n=20) or PBS (group 2, n=24) through the portal vein or into the spleen. Survival analyses in 3 days showed that all animals from group 1 survived, whereas 5 rats from group 2 died (P=0.03), all deaths occurred in rats that received PBS into the portal vein (P=0.001). Alanine aminotransferase and factor V levels measured within the experiment did not differ between groups 1 and 2 at any time point. Molecular analysis and histology showed presence of hepatocytes in liver of transplanted animals injected either through portal vein or spleen. Our data in acetaminophen-induced hepatotoxicity model (1g/kg) demonstrate that rat hepatocyte transplantation increases survival when the site of injection is into portal vein in this hepatotoxicity model. In the acetaminophen-induced acute hepatotoxicity model (1,5g/kg), hepatocytes were isolated from male Wistar rats and transplanted 6 hours later in female recipients. Female rats received either 1x107 hepatocytes (group1, n=33) or PBS (group 2, n=24) into the spleen. Survival analyses in 3 days showed that 9 rats from group 1 and 9 rats from group 2 died at day 2. There was no statistical significance in survival between group 1 and group 2. Our data demonstrate that hepatocyte isolation is a feasible procedure. Hepatocyte transplantation can be used in animal models of acute liver failure increasing survival. The model of the present study show a higher variability, therefore it´s necessary to evaluate hepatocyte transplantation in a more reproducible model.
544

Transplante de hepatócitos no modelo experimental de hepatotoxicidade aguda induzida por paracetamol em ratos

Rodrigues, Daniela January 2012 (has links)
O transplante de hepatócitos é uma modalidade terapêutica atrativa para as doenças hepáticas, assim como uma alternativa para o transplante hepático. O objetivo do presente estudo é investigar a efetividade do transplante de hepatócitos de ratos nos modelos de hepatotoxicidade aguda induzida por paracetamol (1g/kg e 1,5g/kg). Os hepatócitos foram isolados de ratos Wistar machos e transplantados 24 horas após em receptoras fêmeas com hepatotoxicidade de 1g/kg. Os ratos fêmeas receberam 1x107 hepatócitos (grupo 1, n=20) ou PBS (grupo 2, n=24) através da veia porta ou no baço. A análise de sobrevida em 3 dias demonstrou que todos os animais do grupo 1 sobreviveram, enquanto 5 animais do grupo 2 morreram (P=0,03), todas as mortes ocorreram nos ratos que receberam PBS através da veia porta (P=0,001). Os níveis de alanina aminotransferase e fator V que foram medidos no experimento não mostraram diferença entre o grupo 1 e o grupo 2 em nenhum momento. A análise molecular e a histologia mostraram a presença de hepatócitos no fígado de animais transplantados através da veia porta ou pelo baço. O modelo de hepatotoxicidade aguda induzida por paracetamol (1g/kg) demonstrou que o transplante de hepatócitos de ratos aumenta a sobrevida quando o local de injeção é na veia porta. No modelo de hepatotoxicidade aguda induzida por paracetamol (1,5g/kg), os hepatócitos foram isolados de ratos Wistar machos, e transplantados 6 horas após em receptoras fêmeas. Os ratos fêmeas receberam 1x107 hepatócitos (grupo 1, n=33) ou PBS (grupo 2, n=24) no baço. A análise de sobrevida em 3 dias demonstrou que 9 animais do grupo 1, e 9 animais do grupo 2 morreram no dia 2. Não houve diferença estatística significativa na análise de sobrevida entre o grupo 1 e o grupo 2. Nossos dados demonstram que o isolamento de hepatócitos é um procedimento factível. O transplante de hepatócitos é uma técnica que pode ser aplicada em modelos animais de IHA levando ao aumento da sobrevida. Entretanto, o modelo utilizado no presente estudo apresentou um alto grau de variabilidade, tornando necessária a avaliação do transplante de hepatócitos em um modelo mais reprodutível. / Hepatocyte transplantation is an attractive therapeutic modality for liver disease as an alternative for liver transplantation. The aim of the current study was to investigate the effectiveness of rat hepatocyte transplantation in the acetaminophen-induced acute hepatotoxicity models (1g/kg and 1,5g/kg). Hepatocytes were isolated from male Wistar rats and transplanted 24 hours later in female recipients with hepatotoxicity of 1g/kg of acetaminophen. Female rats received either 1x107 hepatocytes (group1, n=20) or PBS (group 2, n=24) through the portal vein or into the spleen. Survival analyses in 3 days showed that all animals from group 1 survived, whereas 5 rats from group 2 died (P=0.03), all deaths occurred in rats that received PBS into the portal vein (P=0.001). Alanine aminotransferase and factor V levels measured within the experiment did not differ between groups 1 and 2 at any time point. Molecular analysis and histology showed presence of hepatocytes in liver of transplanted animals injected either through portal vein or spleen. Our data in acetaminophen-induced hepatotoxicity model (1g/kg) demonstrate that rat hepatocyte transplantation increases survival when the site of injection is into portal vein in this hepatotoxicity model. In the acetaminophen-induced acute hepatotoxicity model (1,5g/kg), hepatocytes were isolated from male Wistar rats and transplanted 6 hours later in female recipients. Female rats received either 1x107 hepatocytes (group1, n=33) or PBS (group 2, n=24) into the spleen. Survival analyses in 3 days showed that 9 rats from group 1 and 9 rats from group 2 died at day 2. There was no statistical significance in survival between group 1 and group 2. Our data demonstrate that hepatocyte isolation is a feasible procedure. Hepatocyte transplantation can be used in animal models of acute liver failure increasing survival. The model of the present study show a higher variability, therefore it´s necessary to evaluate hepatocyte transplantation in a more reproducible model.
545

Resposta do sistema imunológico e do metabolismo intermediário de ratos wistar machos tratados com nonilfenol etoxilado

Matos, Eduardo Pompeo de 16 April 2018 (has links)
O nonilfenol etoxilado (NPE) é um desregulador endócrino que está presente no meio ambiente devido ao seu uso como detergente nos processos de limpeza de efluentes industriais. O objetivo deste trabalho foi avaliar a influência do NPE sobre o sistema imune adaptativo em ratos Wistar machos. Nestes animais foram avaliados o efeito do NPE sobre as células linfocitárias periféricas através da realização de hemograma e do perfil linfocitário adaptativo, analisando os marcadores de superfície CD4, CD8, CD28 e CD45 RA. Foi também avaliado o efeito do tratamento sobre o fígado e baço, bem como sobre o metabolismo intermediário, através das análises de glicemia, triglicerídeos e colesterol. Os dados não demonstraram diferenças significativas em relação ao índice hepático e esplênico. O nível de triglicerídeos apresentou um aumento de 50% nos grupos tratados, na avaliação dos níveis de colesterol e glicose não foi demonstrado diferenças significativas entre os grupos. Os resultados indicaram que o número de linfócitos e monócitos dos grupos tratados tiveram uma queda significativa de aproximadamente 25% e 50% em relação ao grupo controle. Foi demonstrado que o número de células fortemente marcadas quanto à presença da proteína CD45RA High na superfície celular dos linfócitos é maior nas células dos ratos do grupo tratado e que o tratamento aumenta a relação entre as células CD45RA High/Dim. Esses resultados levantam a hipótese que as células aumentadas nos grupos tratados apresentam fenótipo de membrana compatível com células T terminalmente diferenciadas (TEMRA). Este estudo forneceu dados novos sobre a ação do NPE, até onde se tem conhecimento, é a primeira pesquisa a constatar a presença elevada de células TEMRA em animais tratados com NPE, contribuindo com um novo foco para futuras pesquisas dessa substância. / Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq / Ethoxylated nonylphenol (NPE) is an endocrine disruptor that is present in the environment because of its use as a detergent in the industrial effluent cleaning processes. The objective of this work was to evaluate the influence of ethoxylated nonylphenol (NPE) on the adaptive immune system in male Wistar rats. In these animals, the effect of NPE on peripheral lymphocyte cells was evaluate by performing hemogram and adaptive lymphocytic profile, analyzing CD4, CD8, CD28 and CD45 RA surface markers. The effect of treatment on the liver and spleen, as well as on the intermediate metabolism, was also evaluate through glycemic, triglyceride and cholesterol analyzes. The data did not show significant differences in relation to the hepatic and splenic index. The level of triglycerides presented a 50% increase in the treated groups; in the evaluation of cholesterol and glucose levels, no significant differences between the groups were demonstrate. The results indicated that both, the number of lymphocytes and monocytes of the treated groups had a significant decrease of approximately 25% and 50% relative to the control group. The number of strongly labeled cells for the presence of the CD45RA High protein on the cell surface of the lymphocytes showed to be higher in the cells of the mice in the treated group and that the treatment increases the ratio between the CD45RA High/Dim cells. These results raise the hypothesis that enlarged cells in the treated groups exhibit terminally differentiated T cell (TEMRA). This study provided new data on the action of NPE, to the best of our knowledge, is the first research to verify the elevated presence of TEMRA cells in animals treated with NPE. In addition, these findings contribute a new focus for future research on this substance.
546

Influencia do estrogeno e do anti-estrogeno tamoxifeno sobre a dinamica testicular de ratos / Influence of estrogen and anti-estrogen tamoxifen on the testicular dynamics of rats

Pinto-Fochi, Maria Etelvina 15 August 2005 (has links)
Orientador: Rejane Maira Goes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-05T20:48:06Z (GMT). No. of bitstreams: 1 Pinto_MariaEtelvina_M.pdf: 13780138 bytes, checksum: 687200b70b6f4ab0abe1ba1bd2d7243a (MD5) Previous issue date: 2005 / Resumo: Embora seja bem conhecido que o estrógeno é essencial para o adequado desenvolvimento embrionário e maturação pós-natal do testículo, seu papel específico para a fisiologia testicular e em especial para a espermatogênese ainda permanece pouco compreendido. O objetivo do presente estudo foi determinar o impacto da administração subcutânea de uma dose única (35 mg/kg de peso corporal) de benzoato de estradiol e do anti-estrógeno Tamoxifeno sobre o testículo de ratos jovens (5 semanas de idade). Os efeitos do desequilíbrio hormonal passageiro foram avaliados uma (curto prazo) e sete semanas (médio prazo) após os referidos tratamentos com o uso de análises de rotina em microscopia de luz e microscopia eletrônica de transmissão, associadas a análises morfométricas e estereológicas e também pelo método de TUNEL para a detecção de células apoptóticas. O estrógeno afetou mais drasticamente a estrutura testicular e a espermatogênese quando comparado com o Tamoxifeno. Em curto prazo, a exposição à alta dose de estrógeno reduziu em 50% o peso testicular, diminuiu o diâmetro dos túbulos seminíferos e a população de células de Sertoli, induziu um aumento na apoptose das espermátides alongadas acarretando seu desaparecimento. Embora o índice gônadosomático tenha se recuperado sete semanas após a injeção de estrógeno, a taxa de apoptose das células germinativas ainda permanece 5 vezes mais alta e o número de espermátides alongadas é muito inferior ao encontrado nos animais controle. Em curto prazo, a exposição ao Tamoxifeno foi menos prejudicial para o testículo de ratos jovens em comparação com o estrógeno, mas, em médio prazo, resultou em alguns efeitos semelhantes tais como redução do diâmetro dos túbulos seminíferos, incidência elevada de células germinativas apoptóticas, e atrofia de células de Leydig. A partir dos resultados obtidos concluímos, que tanto a exposição passageira ao estrógeno como ao Tamoxifeno interfere negativamente na dinâmica testicular de ratos jovens, levando a danos na espermatogênese que persistem nos animais adultos com uma provável redução da fertilidade / Abstract: Although it is a consensus that estrogen is essential for normal embryonic development and postnatal maturation of the testis, its specific role to the testicularphysiology and in particular to spermatogenesis, is still little understood The aim of the present research was to determine the impact of a single high dose (35mg1kg of body weight) of estrogen and anti-estrogen Tamoxifen, administered subcutaneously in 5-weekold rats, on the testis structure and spermatogenesis. The effects ofthese transient hormonal disruptions were evaluated one (short-term) and seven weeks (medium-term) after treatments by light and transmission electron microscopies, both associated to morphometric and stereological analysis. Moreover, TUNEL's method was employed in order to detect the apoptotic process on germ cells. The estrogen affected more drastically the testicular structure and the spermatogenesis when compared to Tamoxifen. In short term ana1ysis,the exposure to high doses of estrogen caused a 50% reduction in the testis weight, besides a reduction in the diameter of seminiferous tubules and population of Sertoli cells. This treatment also induced an increase in apoptosis and a total destruction of elongated spermatids. Even though the gonad-somatic-index had been recovered within seven weeks after the estrogen injection, apoptotic germ cell rate still remained tive times higher and the number of elongated spermatids was lower than that found in the control animal group. In short term, the exposure to Tamoxifen was less harrnful to the testis of young rats when compared to the estrogen, but in medium term it resulted in some similar effects such as the reduction of the seminiferous tubule diameter, high occurrence of germ apoptotic cells, and Leydig cell atrophy. Based on these results we conclude that transient exposure to estrogen and Tamoxifen induces aherations in testicular dynamics of young rats with a probable damage to the spermatogenesis of aduh animais / Mestrado / Biologia Celular / Mestre em Biologia Celular e Estrutural
547

Efeitos da suplementação de galactooligossacarideo e polidextrose sobre a absorção de calcio e ferro em ratos gastrectomizados / Effects of supplementation of the galactooligosaccharides and polydextrose on the calcium and iron absorption in gastrectomizad rats

Santos, Elisvânia Freitas dos, 1981- 08 February 2007 (has links)
Orientador: Celio Kenji Miyasaka / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T22:13:39Z (GMT). No. of bitstreams: 1 Santos_ElisvaniaFreitasdos_M.pdf: 2673339 bytes, checksum: 01f9989c4a79dc7f5bd8198db02dde80 (MD5) Previous issue date: 2007 / Resumo: O câncer gástrico é o crescimento desordenado de células malignas nos tecidos do estômago e a cirurgia de ressecção gástrica parcial ou total é a principal alternativa terapêutica. Em decorrência deste procedimento cirúrgico podem ocorrer deficiências na absorção de alguns minerais como o cálcio e o ferro, podendo levar a osteoporose e a anemia, respectivamente. Os galactooligossacarídeos (GOS) e a polidextrose (POLI) são componentes fermentáveis que diminuem o pH intestinal favorecendo a absorção de minerais, melhorando a biodisponibilidade. Sendo assim, o objetivo desse trabalho foi verificar o efeito da suplementação desses compostos na absorção do mineral cálcio e ferro em ratos gastrectomizados. Ratos adultos foram submetidos a um procedimento cirúrgico de gastrectomia associado à vagotomia troncular anterior sendo divididos em dois grupos: gastrectomizados (GXT) e falso gastrectomizados (SHAM). Após 15 dias de pós-operatório foram divididos em oito sub-grupos:(G1= GXT / C1=Sham: dieta sem prebiótico; G2=GXT / C2=Sham: GOS 5%; G3=GXT / C3=Sham: POLI 5%; G4=GXT /C4=Sham: GOS 2,5% + POLI 2,5%). Os animais gastrectomizados apresentaram menor consumo de dieta, porém sem diferença com relação ao peso. As dosagens de cálcio sérico e urinário foram menores nos animais gastrectomizados. A gastrectomia diminuiu a absorção aparente de cálcio, sendo que, a administração diária de GOS 5% e a POLI 5% aumentaram a absorção aparente de cálcio em C2 (48%) e C3 (52%) comparados ao C1. O procedimento cirúrgico diminuiu a absorção aparente de ferro em 60%. No entanto, em relação aos tratamentos a associação do GOS + POLI 2,5% aumentou em 52% a absorção de ferro no grupo C4 e 100% no G4. Além disso, o G4 apresentou a mesma absorção dos ratos que não sofreram nenhum tipo de tratamento e nem a cirurgia (C1). A POLI 5% também aumentou a absorção aparente de ferro em 73% em ratos GXT. Os animais do grupo Sham mantiveram os níveis de hematócrito e hemoglobina durante o período experimental. Já nos animais GXT, todos os tratamentos apresentaram redução de 14% nos níveis de hematócrito do tempo inicial à quarta semana. A partir da quarta semana, todos animais GXT apresentaram uma leve tendência de recuperação, contudo os animais do grupo Poli 5% (G3) apresentaram uma plena recuperação. As dosagens de VCM e HCM foram menores nos animais GXT vs CO durante as 8 semanas do experimento, caracterizando uma anemia por deficiência de ferro (microcítica e hipocrômica), respectivamente. A concentração de ferro sérico foi menor nos animais GXT. A suplementação dos dois prebióticos aumentou em 15% o ferro sérico dos animais C4 em relação ao C1. Nos animais GXT o G3 em 51% e G4 em 94% foram maiores do que o G1. A ressecção gástrica parcial não apresentou grandes alterações no metabolismo de cálcio, sugerindo que esse protocolo experimental não seja o melhor modelo para a depleção de cálcio. A ressecção gástrica parcial induziu à má absorção de ferro, comprovando a eficiência do nosso modelo experimental para estudos relacionados ao metabolismo do ferro e há fortes evidências que a junção dos dois prebióticos GOS e POLI atuem como sinergistas, potencializando o efeito prebiótico / Abstract: The gastric cancer is a uncontrolled growth of the cells of the stomach, where the total or parcial gastric surgical resection is the main therapeutic alternative. Due to this procedure, the deficiencies in the absorption of some minerals such as calcium and iron could lead to an osteoporosis and anemia, respectively. The galactooligossacharides (GOS) and the polidextrose (POLI) are fermentable compounds that reduce the intestinal pH increasing the mineral absorption. Thus the purpose of this study was to verify the effects of supplementation of this compound in the absorption of calcium and iron in gastrectomized rats. Adult male rats were submitted to a gastrectomized surgical procedure associated to an anterior troncular vagotomy, them shared in two groups: gastrectomized (GXT) and Sham operated (SHAM) rats. After 15 days of surgery, the rats were shared in 8 sub-groups with the following diets: G1= GTX /C1=Sham: diet without prebiotics; G2= GTX /C2=Sham: 5% GOS diet; G3= GTX /C3=Sham: 5% POLI diet and G4= GTX /C4=Sham: 2.5% GOS + 2.5 POLI diet. The gastrectomized animals ingested a minor amount of feed, however this tow groups not showed differences in the body weight. The calcium in the serum and in the urine in the gastrectomized animals were reduced. The gastrectomy reduced the calcium apparent absorption, the daily administration of 5% GOS and 5% POLI increased the calcium apparent absorption in C2 (48%) and C3 (52 %) as compared to C1 group. The surgical procedure reduced the iron apparent absorption in 60%. However, the associated treatment with GOS + POLI 2,5% increased (52%) the absorption of iron in the C4 group and in the G4 group in 100%, as compared to C1 and G1 group respectively. This group also shoed the same absorption of rats which did not suffer any kind of surgery nor treatment (C1). The 5% POLI also presented an increased iron apparent absorption (73%) in GXT rats. The animals of Sham group sustained the hematocrit and hemoglobin during the experimental period. The GXT animals of all of the different diets showed a reduced hematocrit in 14% from the surgery to the 4th week. From the 4th to the 8th week all of the GXT animals showed a slight trend of recuperation, but the animals of 5% POLI group (G3) presented a full replenishment. The mean corpuscular volume (MCV) and the mean hemoglobin volume (MHV) were reducer in the GXT vs Sham animals during the 8 weeks of experimental period, this is a characteristic of anemia by an iron deficiency (microcitic and hypocromic). The concentration of iron in the serum was lower in the GXT animals. The supplementation of these two prebiotics (C4) increased (15%) the iron in the serum, also the GXT animals the G3 (51%) and G4 (94%) higher than the G1 group. The partial gastric resection did not showed sensible alteration in the calcium metabolism, suggesting that this protocol may not be the best model to the calcium depletion, however, it induced to a poor iron absorption proving the efficiency of our experimental model to the studies related to the iron metabolism and there are strong evidences that the association of GOS and POLI could have a synergistic effect increasing the effects of the prebiotics / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição
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Estrutura do trato genital e função reprodutiva da prole masculina e feminina de ratos expostos ao propionato de testosterona in útero e durante a lactação / Structure of the genital tract and reproductive function of male and female rats exposed to testosterone propionate in utero and during lactation

Guerra, Marina Trevizan, 1985- 22 August 2018 (has links)
Orientador: Wilma De Grava Kempinas / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T22:18:22Z (GMT). No. of bitstreams: 1 Guerra_MarinaTrevizan_D.pdf: 6009222 bytes, checksum: 1ca90ae1ef82035a0e6930b277dac172 (MD5) Previous issue date: 2013 / Resumo: Os desreguladores endócrinos são substâncias químicas que podem mimetizar ou antagonizar os hormônios endógenos, alterando o equilíbrio hormonal necessário para o desenvolvimento correto. Sabe-se que a exposição de organismos a agentes hormonalmente ativos durante períodos críticos do desenvolvimento pode levar a alterações permanentes detectadas somente na vida adulta. Em várias espécies animais estes compostos podem atingir o feto via placenta ou a prole, pelo leite materno. Embora pesquisas iniciais tenham focado em estrógenos e antiandrógenos ambientais, a presença de compostos com atividade androgênica tem sido descrita como contaminante em rios e animais destinados a alimentação. Vários estudos demonstraram que a exposição de animais a altos níveis de andrógenos durante o período perinatal pode causar alterações morfológicas, bioquímicas e funcionais permanentes em vários órgãos e sistemas. A exposição perinatal a andrógenos exógenos pode causar masculinização fisiológica e comportamental em fêmeas e levar a alterações reprodutivas em machos. O objetivo deste trabalho foi avaliar os possíveis efeitos da exposição a um agente androgênico sobre o sistema genital e a função reprodutiva de animais expostos durante períodos críticos de desenvolvimento. Para tanto, ratas prenhes foram alocadas em quatro grupos experimentais: controle, que recebeu somente óleo de milho (veículo), e tratados com propionato de testosterona nas doses de 0,05mg/kg, 0,1mg/kg, ou 0,2mg/kg. Os tratamentos foram realizados por via subcutânea, do dia gestacional 12 ao final da lactação. A prole feminina foi avaliada quanto ao número de células germinativas fetais, peso corpóreo e distância anogenital no dia pós-natal 1, número de mamilos, idade de instalação da puberdade, histologia uterina e ovariana, dosagens hormonais, comportamento sexual, fertilidade, níveis de receptores esteroides uterinos através de imunohistoquímica, assim como taxa de proliferação/morte celular uterina e testes uterotróficos. Nos filhotes do sexo masculino foram avaliados, na idade adulta e meia idade, a histologia testicular e epididimária, contagens, morfologia e motilidade espermáticas, dosagens hormonais, comportamento sexual e fertilidade. Os resultados demonstraram que em fêmeas, a exposição perinatal ao propionato de testosterona ocasionou alteração na intensidade de marcação dos receptores esteroides uterinos em todas as doses testadas, diminuição nos índices de proliferação e morte celular no tecido uterino nas doses de 0,1 e 0,2mg/kg e aumentou a predisposição uterina a responder a estímulos estrogênicos na dose de 0,1mg/kg e 0,2mg/kg. Entretanto, estas alterações não foram capazes de prejudicar a diferenciação sexual feminina e a fisiologia normal do sistema genital feminino. Em relação aos filhotes do sexo masculino, a exposição perinatal a andrógenos provocou redução na produção e nas reservas espermáticas na idade adulta, sem, contudo, alterar a fertilidade destes animais após acasalamentos naturais. Podemos concluir que a exposição perinatal a andrógenos, nas doses utilizadas neste experimento, provocou o aparecimento de alterações tardias no sistema genital feminino como modificações nos receptores esteroides uterinos e anormalidade na resposta a estímulos estrogênicos e, no sistema genital masculino, alterações na produção espermática. Estas repercussões, entretanto, não foram capazes de alterar o desempenho geral de fertilidade em ambos os sexos / Abstract: Endocrine disruptors are chemicals that may mimic or antagonize endogenous hormones, altering the critical hormonal balance required for proper health and development. It is well known that exposure of organisms to some hormonally active agents during critical periods of development imprints permanent changes that can be detected later in adulthood. In many animal species these substances reach the fetus via placenta and/or the offspring via the mother's milk. Although first researches have focused on environmental estrogens and antiandrogens, androgenic activity has been described as contaminant in rivers and beef cattle. Previous studies demonstrated that exposure of experimental animals to high levels of androgens during perinatal age causes permanent morphological, biochemical, and functional alterations in several organs and systems. Perinatal exposure of female rodents to exogenous androgens results in both physiological and behavioral masculinization and causes reproductive disruption in male rodents. The aim of this study was to assess the possible effects of an androgenic compound on genital system and reproductive function of animals exposed during critical periods of development. Pregnant female rats were allocated into four experimental groups: control, which received corn oil (vehicle), and treated with testosterone propionate at doses of 0.05mg/kg, 0.1mg/kg and 0.2mg/kg. Treatments were performed subcutaneously, from gestational day 12 until the end of lactation. The female offspring was evaluated for fetal germ cell number, body weight and anogenital distance at post-natal day 1, number of nipples, puberty onset, histology of reproductive organs, hormonal levels, sexual behavior, fertility test, immunohistochemistry of steroid receptors, proliferation/apoptotic index, uterotrophic test and uterine stimulation with estrogens. On male offspring, at adult age and middle-age, histology of testis and epididymis, sperm counts, morphology and motility, hormonal levels, sexual behavior and fertility test were evaluated. Results demonstrated that, in females, the perinatal testosterone propionate exposure caused an alteration in the pattern of uterine steroidal receptors imunostaining in all tested doses, a decreased proliferation/apoptotic index in the uterine tissue at 0.1 and 0.2mg/kg and a greater predisposition from uterus in responding to estrogens stimulation at dose of 0.2mg/kg. However, these alterations were not capable of impairing female sexual differentiation and normal physiology of female genital tract. On male offspring, the perinatal androgenization provoked a reduction in sperm production and reserves at adult age, without altering fertility after natural mating. We can conclude that perinatal exposure to androgens, at doses used in this experiment, provoked the appearance of late alterations in the female genital system as modifications in the uterine steroidal receptors and abnormalities in uterine response to estrogenic stimulation, and in male genital system, as spermatic production impairment. These repercussions, however, were not capable to alter the general fertility performance in both sexes / Doutorado / Biologia Celular / Doutora em Biologia Celular e Estrutural
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Estudo dos efeitos do material particulado proveniente da biomassa de cana-de-açúcar sobre o aparelho respiratório e circulatório de ratos wistar combinados ou não com a infecção estafilocócica / Study of the effects of particulate matter from sugarcane biomass over wistar rats respiratory and circulatory systems combined or not with staphylococcal infection

Bittar, Telmo Oliveira 07 March 2013 (has links)
Orientador: Antonio Carlos Pereira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-23T16:01:28Z (GMT). No. of bitstreams: 1 Bittar_TelmoOliveira_D.pdf: 2703119 bytes, checksum: 534783a3c2c8593748bf07a81c8e04e3 (MD5) Previous issue date: 2013 / Resumo: Inúmeros relatos da literatura apontam para associações entre poluição atmosférica e patologias do aparelho respiratório e cardíaco. O objetivo deste estudo foi averiguar os efeitos do material particulado oriundo da queima da biomassa da cana-de-açúcar no aparelho respiratório e cardíaco de ratos machos wistar. Utilizou-se de um forno especialmente desenhado para coletar o material particulado proveniente da palha da cana de- açúcar e então isolá-lo. Sua análise química foi feita por cromatografia gasosa. Posteriormente foram alocados 4 grupos, de 7 ratos cada, dividindo-os na seguinte ordem: grupo I- recebeu instilação de material particulado em soro fisiológico; grupo II- recebeu instilação de material particulado e S. aureus; grupo III- controle, recebeu apenas instalação de soro fisiológico; grupo IV- recebeu apenas instilação de S. aureus. Após o período de uma semana, os animais foram eutanasiados, e foram coletadas amostras de pulmão, traquéia e coração para análise histológica, morfométrica e de imunoensaio. A metodologia utilizada para análise histológica e morfométrica foi a de comparação ao padrão de normalidade, e teste ELISA de captura no imunoensaio para as seguintes citocinas: GRO-?, IL-1?, IL-1?, IL-6, IFN-?, TNF-?. Os resultados analisados mostraram que o principal componente encontrado no material particulado de cana de açúcar foi o éster de ácido ftálico. Não houve nenhuma alteração estatística entre os grupos em relação ao tecido cardíaco. A análise histológica revelou alteração no padrão de normalidade apenas no grupo IV. Na análise morfométrica da traquéia, foi observada uma redução no espessamento do tecido conjuntivo no grupo II, e nas medidas de centro, todos os grupos apresentaram diferenças significativas em relação ao controle. Em relação ao imunoensaio, observou-se que os grupos I e II expressaram a liberação de IL-1? em relação ao controle. O grupo I apresentou expressão significativa de IL-6 em relação ao controle e grupo IV, e de IL-1 ? e IFN-? com relação aos demais grupos. Deste modo, o presente estudo mostrou que o material particulado, oriundo da queima da biomassa da cana-de-açúcar, é capaz de provocar alteração no aparelho respiratório de ratos wistar e motivar a produção de citocinas / Abstract: Several studies point out the association between atmospheric pollution and pathologies from respiratory and cardiac systems. The aim of this study was to analyze the effects of the particulate matter from sugar cane biomass in respiratory and cardiac systems of male wistar rats. It was used a special developed oven to collect the sugar cane particulate matter and so isolate it. Its chemical analysis was done by gas chromatography. Later it was allocated 4 groups each one with 7 rats been divided into: group I- received instillation of only particulate mater in physiological saline; group II- received particulate matter plus S. aureus; group III- control group with only physiological saline; group IV- received only S. aureus. After one week, the animals were euthanized and samples were gathered from lung, heart and trachea tissues to histological, morphometric and immunoassays analysis. The histological and morphometric employed methodology was the normality standard variation and ELISA capture test for immunoassays for the following cytokines: GRO-?, IL-1?, IL-1?, IL-6, IFN-?, TNF-?. Analyzed results shown the main substance found in sugar cane particulate matter was phthalic acid ester. None standard variation statically for heart tissue was found. Histological analysis revealed changes in the normal pattern only in group IV. In trachea morphometric analysis it was observed the decreasing in its conjunctive tissue width for group II, and in its center measurement all the groups presented significant difference when compared to control group. In the immunoassays it was noted that group I and II expressed the production of IL-1? when compared to control group. The group I presented a significant expression of IL-6 compared to control group and group IV; and IL-1 ? e IFN-? when compared to the other groups. Based on this achieves, the present study has shown the sugar cane particulate matter is capable to produce alteration in respiratory system of wistar rats and motivate cytokines production / Doutorado / Saude Coletiva / Doutor em Odontologia
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Attenuated Activity across Multiple Cell Types and Reduced Monosynaptic Connectivity in the Aged Perirhinal Cortex

Maurer, Andrew P., Burke, Sara N., Diba, Kamran, Barnes, Carol A. 13 September 2017 (has links)
The perirhinal cortex (PER), which is critical for associative memory and stimulus discrimination, has been described as a wall of inhibition between the neocortex and hippocampus. With advanced age, rats show deficits on PER-dependent behavioral tasks and fewer PER principal neurons are activated by stimuli, but the role of PER interneurons in these altered circuit properties in old age has not been characterized. In the present study, PER neurons were recorded while rats traversed a circular track bidirectionally in which the track was either empty or contained eight novel objects evenly spaced around the track. Putative interneurons were discriminated from principal cells based on the autocorrelogram, waveform parameters, and firing rate. While object modulation of interneuron firing was observed in both young and aged rats, PER interneurons recorded from old animals had lower firing rates compared with those from young animals. This difference could not be accounted for by differences in running speed, as the firing rates of PER interneurons did not show significant velocity modulation. Finally, in the aged rats, relative to young rats, there was a significant reduction in detected excitatory and inhibitory monosynaptic connections. Together these data suggest that with advanced age there may be reduced afferent drive from excitatory cells onto interneurons that may compromise the wall of inhibition between the hippocampus and cortex. This circuit dysfunction could erode the function of temporal lobe networks and ultimately contribute to cognitive aging.

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