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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.
441

The individual and combined effects of exercise and collagenase on the rodent Achilles tendon

Dirks, Rachel Candace 11 July 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Tendinopathy is a common degenerative pathology that is characterized by activity related pain, focal tendon tenderness, intratendinous imaging changes, and typically results in changes in the histological, mechanical, and molecular properties of the tendon. Tendinopathy is difficult to study in humans, which has contributed to limited knowledge of the pathology, and thus a lack of appropriate treatment options. However, most believe that the pathology is degenerative as a result of a combination of both extrinsic and intrinsic factors. In order to gain understanding of this pathology, animal models are required. Because each tendon is naturally exposed to different conditions, a universal model is not feasible; therefore, an appropriate animal model must be established for each tendon susceptible to degenerative changes. While acceptable models have been developed for several tendons, a reliable model for the Achilles tendon remains elusive. The purpose of this dissertation was to develop an animal model of Achilles tendinopathy by investigating the individual and combined effects of an intrinsic and extrinsic factor on the rodent Achilles tendon. Rats selectively bred for high capacity running and Sprague Dawley rats underwent uphill treadmill running (an extrinsic factor) to mechanically overload the Achilles tendon or served as cage controls. Collagenase (intrinsic factor) was injected into one Achilles tendon in each animal to intrinsically break down the tendon. There were no interactions between uphill running and collagenase injection, indicating that the influence of the two factors was independent. Uphill treadmill running alone failed to produce any pathological changes in the histological or mechanical characteristics of the Achilles tendon, but did modify molecular activity. Intratendinous collagenase injection had negative effects on the histological, mechanical, and molecular properties of the tendon. The results of this dissertation demonstrated that the combined introduction of uphill treadmill running and collagenase injection did not lead to degenerative changes consistent with human Achilles tendinopathy. Intratendiouns collagenase injection negatively influenced the tendon; however, these changes were generally transient and not influenced by mechanical overload. Future studies should consider combinations of other intrinsic and extrinsic factors in an effort to develop an animal model that replicates human Achilles tendinopathy.
442

Does binge drinking induce PMDD-like dysfunction for female C57BL/6J mice? : implications for sex differences in addiction vulnerability

Melón, Laverne C. January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / It has traditionally been posited that women show a "telescoped" development of alcohol use disorders (Kuhn, 2011). In particular, a number of clinical studies support striking sex differences in the progression from initial use of alcohol to dependence on the compound; with women showing a faster progression through landmark events associated with the development of alcohol addiction (Randall et al., 1999). However, recent studies have challenged this tenet (Keyes et al., 2010). The work presented herein was designed to determine whether females are indeed more vulnerable to the development of behavioral maladaptations following binge drinking and whether sex differences in GABA(A) receptor regulation might underlie this vulnerability. Using a mouse model of binge drinking this dissertation established that, compared to males, females escalate their binge drinking at a faster rate and maintain altered responsivity to the locomotor effects of alcohol after extended abstinence from binge drinking. Female mice also displayed significant increases in ethanol preference and intake in a continuous, two-bottle choice protocol following a shorter history of binge drinking than males. The final goal was to determine if binge drinking results in unique patterns of anxiety- or depressive-like symptoms in males and females and whether these behaviors would be associated with the dimorphic regulation of GABAA receptor subunits across the prefrontal cortex and hippocampus. Male binge drinkers displayed anxiety-like behavior during early withdrawal that dissipated after 2 weeks of abstinence. There were no significant changes in the expression of delta or gamma2 GABAA receptor subunit mRNA at this time point in the regions analyzed. Females also showed temporary anxiety-like behavior during early withdrawal from binge drinking. Additionally, females displayed significant depressive-like behavior after 2 weeks of abstinence from binge drinking. In particular, diestrus-phase females displayed significantly greater immobility in the forced-swim test after ethanol exposure and no longer maintained the reduced swim-time behavior associated with this phase of the cycle at baseline (when compared to the estrus-phase). qPCR analysis of hippocampal tissues from diestrus females supported a significant reduction in expression of gamma2 GABA(A) subunit mRNA after binge drinking. This effect was not noted for RNA isolated from hippocampal tissues taken during the estrus phase of bingers. These final data suggest possible interaction of estrous-cycle and binge drinking history that may result in the unique expression of deficits following binge drinking for females. Taken together, this work supports sex and estrous dependent effects of binge drinking on behavior and gene regulation.
443

The impact of activation of the renin-angiotensin system in the development of insulin resistance in experimental models of obesity

Perel, Shireen J. C. 03 1900 (has links)
Thesis (MScMedSc (Biomedical Sciences. Medical Physiology))--University of Stellenbosch, 2009. / Insulin stimulates the production of nitric oxide (NO) in endothelial cells and cardiac myocytes by a signalling pathway that involves the insulin receptor substrate (IRS)-1, phosphatidylinositol-3-kinase and protein kinase B (PKB/Akt). Physiological concentrations of NO play an important part in maintaining normal vascular function. It has been suggested that nitric oxide synthase (NOS) activity and NO production are chronically impaired in diabetes mellitus by an unknown mechanism. The reninangiotensin system and subsequent production of angiotensin II (Ang II) are elevated in obesity and diabetes while antagonism of the AT1 receptor with Losartan has beneficial effects in patients with insulin resistance and type II diabetes. Aims: We therefore aimed to investigate (i) the effect of Ang II on myocardial insulin signalling with regards to key proteins (IRS-1, PKB/Akt, eNOS and p38 MAPK) in correlation with NO production, (ii) the effect of Losartan on these parameters. Methods: Hyperphagia-induced obese, insulin resistant rats (DIO=diet supplemented with sucrose and condensed milk) were compared to age-matched controls. Half the animals were treated with 10mg/kg Losartan per day for 1 week. Isolated hearts were perfused with or without 0.03 μIU/mL insulin for 15 min. Blood glucose, bodyweight, intraperitoneal fat and plasma insulin and Ang II were recorded. Proteins of interest and their phosphorylation were determined by Western blotting. NO production was flow cytometrically analyzed. ANOVA followed by the Bonferroni correction was used with a p< 0.05 considered significant. Results: DIO animals had significant elevated bodyweight, blood glucose, plasma insulin and Ang II levels. Our data showed that the hearts from the DIO animals are insulin resistant, ultimately reflected by the attenuated activation of the key proteins (IRS-1, PKB/Akt and eNOS) involved in insulin signalling as well as NO production. AT1 receptor antagonism improved NO production in isolated adult ventricular myocytes from DIO animals while concurrently enhancing expression of eNOS, PKB/Akt and p38 MAPK. In contrast, NO production as well as expression of eNOS and PKB/Akt was attenuated in control animals after Losartan treatment. Conclusion: These results suggested that Ang II via AT1 or AT2 receptors, modulates protein expression of both PKB/Akt and eNOS. This encouraged us to investigate the involvement of AT2 receptors in the observed changes. To investigate this we needed to establish a culture of neonatal rat cardiac myocytes treated with raised fatty acids and Ang II. If similar changes were induced as observed in the hearts of DIO animals, the involvement of the AT1 and AT2 receptors could be investigated using specific antagonists against these receptors. Primary cultured ventricular myocytes were isolated from 1-3 day old Wistar rat pups. They were cultured for 48 hours before the addition of palmitate and oleate at a concentration of 0.25 mM each and were treated with or without the fatty acids for a period of 4 days. After 18 hours of serum starvation, cells were stimulated with or without 10 nM insulin for 15 minutes. The effect of fatty acid treatment on cell viability and glucose uptake were assessed by trypan blue and propidium iodide staining and 2-deoxy-D-3[H] glucose uptake respectively. Protein levels and phosphorylation of key proteins (PKB/Akt, PTEN and p38 MAPK) in insulin signalling was determined by Western blotting. 0.25 mM Fatty acids did not result in the loss of cell viability. Contrary to expectation, fatty acid treatment led to enhanced basal glucose uptake but lower Glut 1 protein expression. Basal protein expression of PPARα was, however, upregulated as was the expression of the phosphatase, PTEN. The latter could explain the lower PKB/Akt phosphorylation also documented. From these results we conclude that neonatal cardiac myocytes, cultured in the presence of elevated fatty acids, did not respond in a similar manner as the intact hearts of our animals and further modifications of the system might be needed before it can be utilized as initially planned.
444

Natural animal model systems to study tuberculosis

Parsons, Sven David Charles 03 1900 (has links)
Thesis (PhD (Molecular Biology and Human Genetics))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The growing global epidemic of human tuberculosis (TB) results in 8 million new cases of this disease and 2 million deaths annually. Control thereof will require greater insight into the biology of the causative organism, Mycobacterium tuberculosis, and into the pathogenesis of the disease. This will benefit the design of new vaccines and diagnostic assays which may reduce the degree of both disease transmission and progression. Animal models have played a vital role in the understanding of the aetiology, pathogenesis, and treatment of TB. Much of such insight has been obtained from experimental infection models, and the development of new vaccines, for example, is dependant on these. Nonetheless, studies utilising naturally occurring TB in animals, such as those which have investigated the use of interferon-gamma release assays (IGRA) for its diagnosis, have contributed substantially to the body of knowledge in this field. However, there are few such examples, and this study sought to identify and investigate naturally occuring animal TB in South Africa as an opportunity to gain further insight into this disease. During the course of this study, the dassie bacillus, a distinctly less virulent variant of M. tuberculosis, was isolated from a rock hyrax from the Western Cape Province of South Africa. This has provided new insight into the widespread occurrence of this organism in rock hyrax populations, and has given impetus to further exploring the nature of the difference in virulence between these pathogens. Also investigated was M. tuberculosis infection in dogs in contact with human TB patients. In so doing, the first reported case of canine TB in South Africa was described, v a novel canine IGRA was developed, and a high level of M. tuberculosis infection in these animals was identified. This supports human data reflecting high levels of transmission of this pathogen during the course of human disease. Additionally, the fact that infected companion animals may progress to disease and potentially act as a source of human infection was highlighted. However, an attempt to adapt a flow cytometric assay to study cell-mediated immune responses during canine TB revealed the limitations of such studies in species in which the immune system remains poorly characterised. The use of IGRAs to diagnose TB was further explored by adapting a human assay, the QuantiFERON-TB Gold (In-Tube Method), for use in non-human primates. These studies have shown that such an adaption allows for the sensitive detection of TB in baboons (Papio ursinus) and rhesus macaques (Macaca mulatta) and may be suitable for adaption for use in other species. However, they have also evidenced the limitation of this assay to specifically detect infection by M. tuberculosis. Finally, to contextualise the occurrence of the mycobacterial infections described above, and other similar examples, these have been reviewed as an opinion piece. Together, these investigations confirm that animal models will continue to make important contributions to the study of TB. More specifically, they highlight the opportunities that naturally occuring animal TB provides for the discovery of novel insights into this disease. / AFRIKAANSE OPSOMMING: Wêreldwye tuberkulose (TB) epidemie veroorsaak agt miljoen nuwe gevalle en twee miljoen sterftes jaarliks. Ingryping by die beheer hiervan vereis begrip van die biologie van die mikroörganisme Mycobacterium tuberculosis, die oorsaak van TB, asook van die patogenese van die siekte self. Hierdie kennis kan lei tot ontwerp van nuwe entstowwe en diagnostiese toetse wat gevolglik beide die oordrag- en vordering van die siekte mag bekamp. Dieremodelle speel lankal 'n rol in ons begrip van die etiologie-, patogenese- en behandeling van TB. Insig is grotendeels verkry vanaf eksperimentele infeksiemodelle, en ontwikkeling van entstowwe, onder andere, is afhanklik van soortgelyke modelle. Desnieteenstaande, studies wat natuurlike TB voorkoms in diere ondersoek, byvoorbeeld dié wat op die ontwikkeling van interferon-gamma vrystellingstoetse (IGVT) fokus, het merkwaardige bydrae gemaak tot kennis en begrip in hierdie studieveld. Daar is slegs enkele soortgelyke voorbeelde. Om hierdie rede is die huidige studie uitgevoer waarbinne natuulike diere-TB geïdentifiseer en ondersoek is in Suid-Afrika om verdere kennis en insig te win aangaande TB. Die "dassie bacillus", bekend om beduidend minder virulent te wees as M. tuberculosis, is tydens hierdie studie geïsoleer vanuit 'n klipdassie (Procavia capensis) in die Wes-Kaapse provinsie, Suid-Afrika. Insig in die wydverspreide voorkoms van hierdie organisme in klipdassie bevolkings is gevolglik verkry en verskaf momentum om die aard van verskil in virulensie tussen dié patogene te bestudeer. vii Voorts is M. tuberculosis infeksie bestudeer in honde wat in kontak is met menslike TB pasiënte en word die eerste geval van honde TB dus in Suid-Afrika beskryf. In hierdie groep diere, is 'n hoë vlak van M. tuberculosis infeksie geïdentifiseer deur gebruik te maak van 'n nuut ontwikkelde IGVT vir die diagnose van honde TB. Gevolglik ondersteun dié studie bevindinge van menslike studies wat toon dat besondere hoë vlakke van M. tuberculosis oordrag voorkom gedurende die verloop van die siekte. Verder toon die studie dat geïnfekteerde troeteldiere 'n bron van menslike infeksie kan wees. 'n Poging om 'n vloeisitometriese toets te ontwikkel om die aard van selgefundeerde immuunreaksies te bestudeer in honde met TB toon die beperkings van dergelike studies in spesies waarin die immuunsisteem gebrekkig gekarakteriseer is. Die gebruik van IGVT'e in die diagnose van TB is verder ondersoek deur 'n menslike toets (QuantiFERON-TB Gold, In-Tube Method) aan te pas vir die gebruik van nie-menslike primaat gevalle. Hierdie studies toon gevolglik dat so 'n aanpassing toepaslik is vir hoogs sensitiewe deteksie van TB in chacma bobbejane (Papio ursinus) en rhesus ape (Macaca mulatta), en mag ook aangepas word vir gebruik in ander spesies. Tog word die beperkings van hierdie toets om infeksie wat spesifiek deur M. tuberculosis veroorsaak uitgelig. Ter afsluiting word hierdie studie in konteks geplaas deur 'n oorsig te gee van bogenoemde- en soortgelyke gevalle van dierlike infeksie deur mikobakterieë in Suid-Afrika. Hierdie studies bevestig dat dieremodelle steeds belangrike toevoegings maak tydens die bestudering van TB en lig veral die moontlikhede uit dat bestudering van natuulike TB in diere kan lei tot die ontdekking van nuwe insigte ten opsigte van die siekte self.
445

Forms of flexibility : associations between executive functions in the rat

Chase, E. Alexander January 2013 (has links)
Executive control is a vital cognitive function that facilitates the focussing and shifting of attention, planning and working towards a goal, ignoring distractions, and flexibly responding to novel situations. Disruptions to executive control are seen in many psychiatric and neurodegenerative disorders, as well as healthy ageing, which can be profoundly detrimental. Despite having many effective and well-validated methodologies for detecting and quantifying these deficits, there are very few treatments — pharmacological or otherwise — for ameliorating executive dysfunction. This lack of progress can partly be blamed on difficulties associated with identifying drugs that enhance cognition in preclinical research. The work in this thesis aimed to expand our understanding of executive dysfunction — as well as the tasks that measure it — in rats. In results presented in chapter three, middle-aged rats demonstrated impaired reversal learning on the standard attentional set-shifting task, but this was treatable with a novel drug targeting the N-methyl-D-aspartate receptor. The age impairments seen in this experiment were similar to those previously found in young rats with orbital prefrontal cortex (OFC) lesions. The results of chapter four expanded on this similarity to show that, along with reversal deficits, young OFC-lesioned rats are impaired at forming attentional sets when tested on a modified task. In chapter five, another modified set-shifting task revealed that middle-aged rats also suffer from impaired set-formation, but their reversal learning impairments only manifest before attentional set has been formed — not after. Finally, in chapter six, the putative cognitive enhancer modafinil was found to exacerbate middle-aged rats' reversal learning deficit, but it also enhanced their subsequent ability to form attentional set. These experiments reveal that modifying the rat attentional set-shifting task can sometimes make it a more effective tool for testing cognitive enhancers in preclinical settings.
446

Sensomotorische Phänotypisierung von Mausmodellen für zentralnervöse Bewegungsstörungen

Gerstenberger, Julia 29 May 2017 (has links) (PDF)
Einleitung: Tiermodelle spielen für die Aufklärung pathophysiologischer Mechanismen und die Entwicklung erfolgsversprechender Therapieoptionen zentralnervöser Bewegungsstörungen eine unverzichtbare Rolle. Die Identifizierung von Gendefekten für die Parkinson-Krankheit und Dystonien ermöglichte die Generierung von Tiermodellen mit einer hohen „construct validity“. Weibliche transgene Thy1-aSyn Mäuse sowie DYT1 Knock-in (KI) Mäuse zeigen jedoch keine motorischen Störungen. In der vorliegenden Arbeit sollten zur Aufdeckung sensomotorischer Beeinträchtigungen, die bei Parkinson- und Dystoniepatienten beobachtet werden, detaillierte Untersuchungen des Verhaltens an diesen beiden Mausmodellen durchgeführt werden. Zielstellung: Zunächst sollte ein sensitiver Verhaltenstest konstruiert und entwickelt werden, bei dem sich ändernde sensorische Stimuli während der Ausübung der motorischen Aufgabe impliziert werden. Bei der Etablierung dieses sogenannten „adaptiven rotierenden Balkentests“ (ARB-Test) sollte auch der Einfluss des genetischen Hintergrunds bei Wildtyp-Mäusen evaluiert werden. Daraufhin sollte überprüft werden, ob dieser Test den Endophänotyp der weiblichen Thy1-aSyn Mäuse aufdecken kann. In dem DYT1 KI Mausmodell sollte der Frage nachgegangen werden, ob die Tiere Verhaltensdefizite in spezifischen Tests zeigen, die sensomotorische Verschaltungen untersuchen. Material und Methoden: Die mRNA-Expression von α-Synuclein in der Substantia nigra bei männlichen und weiblichen Thy1-aSyn Mäusen wurde mithilfe der quantitativen Echtzeit-PCR (qPCR) ermittelt. Im Anschluss an die Entwicklung des neuen Verhaltensapparates für den ARB-Test wurden Thy1-aSyn Tiere beider Geschlechter in diesem Versuch getestet und ihre Leistung den Ergebnissen auf etablierten motorischen Verhaltenstests („challenging beam test“, „pole test“) gegenübergestellt. Um den Einfluss des Hintergrundstammes auf das Verhalten der Tiere auf dem ARB-Test zu untersuchen, wurden Wildtypen der reinen C57BL/6J-Linie sowie Hybrid-Tiere des Stammes C57Bl/6J × DBA2 (BDF1) allen drei o. g. Versuchen unterzogen. Bei den Mäusen des DYT1 KI Modells wurde der „adhesive removal test“ und der ARB-Test zur Analyse der Sensomotorik durchgeführt. Im Vergleich dazu wurden vielfältige Verhaltensparameter in einer Reihe vorwiegend motorischer (Offenfeld-Test, „challenging beam test“, „pole test“, Zylinder-Test, Block-Test, Nestbau-Test) und kognitiver („y-maze test“) Verhaltenstests ausgewertet. Ergebnisse: Bei den weiblichen Thy1-aSyn Mäusen wurde eine geringere Expression des Transgens im Vergleich zu den männlichen Tieren festgestellt. Der neue ARB-Test wurde erfolgreich etabliert und konnte signifikante Verhaltensdefizite der weiblichen und männlichen Mutanten des Parkinson-Modells im Vergleich zu den Kontrolltieren aufdecken. Der genetische Hintergrund beeinflusste die Leistung der Wildtypen auf diesem Balkentest. Während die DYT1 KI Tiere in den rein motorischen und kognitiven Versuchen keine Beeinträchtigungen des Verhaltens zeigten, konnten der „adhesive removal test“ sowie der neue ARB-Test signifikante sensomotorische Defizite der KI Mäuse im Unterschied zu den Wildtypen zum Vorschein bringen. Schlussfolgerung: Im Thy1-aSyn Mausmodell konnte die Bedeutung der sensomotorischen Integration für die Ausprägung motorischer Defizite sowie für eine mögliche Kompensation solcher motorischen Beeinträchtigungen demonstriert werden. Hierfür hat sich der neu entwickelte, sensitive ARB-Test als geeignet herausgestellt. Die Aufdeckung von Beeinträchtigungen der Sensomotorik spricht auch bei den DYT1 KI Tieren für den Einfluss einer gestörten sensomotorischen Integration bei der Ausprägung der Symptomatik. Damit eignet sich dieses Mausmodell für die Untersuchung weiterer Parameter, die Auswirkungen auf die Aufdeckung des Phänotyps und die Penetranz der Erkrankung haben sowie um die zugrunde liegenden pathophysiologischen Mechanismen zu erforschen.
447

Avaliação do estresse oxidativo e expressão de genes envolvidos com síntese e oxidação de ácidos graxos em modelo animal de síndrome dos ovários policísticos tratado com metformina e submetida ao exercício físico / Evaluation of oxidative stress and expression of genes involved with fatty acid synthesis and oxidation in animal model of polycystic ovary syndrome treated with metformin and physical exercise

Gonçalves, Thiago Hideki 04 December 2017 (has links)
Introdução: A síndrome dos ovários policísticos (SOP) é um distúrbio endócrino complexo com aspectos reprodutivos e metabólicos. Alterações do tecido adiposo participam da fisiopatologia da síndrome e anormalidades do metabolismo de ácidos graxos, bem como o estresse oxidativo, parecem ter papel importante nesse processo. Assim, tanto o exercício físico como a metformina são comumente recomendadas. O objetivo deste estudo foi avaliar a expressão de genes envolvidos com a síntese e oxidação dos ácidos graxos e com os níveis de estresse oxidativo no tecido adiposo de ratas com modelo experimental de SOP tratadas com metformina (Met), submetidas ou não a exercício físico em esteira (Ex). Métodos: Foram utilizadas 46 ratas, Wistar, que receberam no 2º dia de vida, uma única injeção subcutânea de propionato de testosterona (1,25 mg) para a indução de estado de estro permanente e óleo de sésamo (controles). Com 80 dias de idade iniciou-se o experimento e os animais foram divididos em 5 grupos: 1) Controle; 2) SOP ; 3) SOP+Met; 4) SOP+Ex; 5) SOP+Met+Ex.Os tratamentos tiveram duração de 6 semanas. Os animais foram sacrificados aos 120 dias de vida e foram retirados os depósitos das gorduras inguinal e mesentérica. Os depósitos de gordura inguinal e mesentérica foram utilizados para análise da expressão dos genes Acaca, Srebp1, Cpt1 e Cd36, por PCR quantitativo em tempo real, e dos níveis de estresse oxidativo pela dosagem das glutationas reduzida (GSH) e oxidada (GSSG). Adicionalmente, o tamanho dos adipócitos foi analisado por histomorfometria. Resultados: Na análise histomorfométrica dos adipócitos da gordura mesentérica, houve diminuição significativa no grupo SOP+Met+Ex em relação ao grupo SOP. O grupo SOP apresentou hipertrofia em relação ao grupo controle. A análise na gordura inguinal não apresentou nenhuma diferença entre os grupos.Não houve diferença estatística entre os grupos nas análises de expressão gênica das gorduras mesentérica e marrom. Não identificamos diferenças nas medidas de estresse oxidativo (razões GSH/GSSG ,GSH, GSH total, GSSG e razão GSH/GSSG) no tecido adiposo subcutâneo, mesentérico, perigonadal e marrom entre os depósitos de gordura dos animais em nenhum dos grupos avaliados / Introduction: Polycystic ovary syndrome (PCOS) is a complex endocrine disorder, affecting both reproductive and endocrine systems. Changes in adipose tissue are involved in the pathophysiology of the syndrome, and abnormalities of fatty acid metabolism, as well as oxidative stress, appear to play an important role in this process. Thus, both physical exercise and metformin are commonly recommended. The objective of this study was to evaluate the expression of genes involved in the synthesis and oxidation of fatty acids and oxidative stress levels in adipose tissue of in an experimental model of PCOS using Wistar rats. Methods: 46 rats, Wistar, treated with a single subcutaneous injection of testosterone propionate (1.25 mg) for the induction of permanent estrus status (PCOS model) or sesame oil (controls) on the 2nd day of life. Experimental phase of the study was started when animals completed 80 days of age. They were divided into 5 groups: 1) Control; 2) PCOS; 3) PCOS+ Met; 4) PCOS + Ex; 5) PCOS + Met + Ex. Intervention lasted 6 weeks. Animals were sacrificed at 120 days of age and the deposits of inguinal and mesenteric fat were removed. Inguinal and mesenteric fat deposits were used to analyze the expression of Acaca, Srebp1, Cpt1 and Cd36 genes by quantitative realtime PCR and oxidative stress levels by reduced (GSH) and oxidized glutathione (GSSG). In addition, adipocyte size was analyzed by histomorphometry. Results: In the histomorphometric analysis of mesenteric fat adipocytes, there was a significant decrease in the PCOS + Met + Ex group in relation to the PCOS group. PCOS group presented hypertrophy in relation to the control group. Inguinal fat analysis did not present any differences between the groups. There was no statistical difference between groups in analyzes of gene expression of mesenteric and brown fats. We did not identify differences in oxidative stress measurements (GSH / GSSG, GSH, total GSH, GSSG and GSH / GSSG ratio) in the subcutaneous, mesenteric, perigonadal and brown adipose tissue among the fat deposits of the animals in any of the evaluated groups
448

Indução de tolerância nasal com colágeno tipo V em modelo experimental de esclerodermia / Collagen V- induced nasal tolerance in scleroderma experimental model

Velosa, Ana Paula Pereira 08 May 2007 (has links)
Objetivo: Verificar o remodelamento da pele e produção de anticorpos em modelo experimental de esclerodermia em coelhos, após indução de tolerância nasal com colágeno tipo V. Métodos: Coelhas Nova Zelândia (N=12) foram imunizadas com 1mg/ml de colágeno V (Col V) em adjuvante completo de Freund e dois reforços com adjuvante incompleto de Freund. Seis coelhas imunizadas receberam uma dose diária de 25ug de Col V, iniciado via nasal (grupo tolerado) 150 dias do começo das imunizações e seis animais foram somente imunizadas (grupo imunizado). Um grupo imunizado com adjuvante de Freund serviu como controle. Biopsias de pele foram coletadas em 0, 75, 120, 150 e 210 dias e coradas pelo H&E, tricrômico de Masson e Sírius red para analise morfológica e morfométrica. Os colágenos I, III e V, além de TGFbeta e PDGF foram imunomarcados por imunofluorescência. Os soros dos animais foram coletados em 0, 150 e 210 dias para determinar anticorpos anti-colágenos I, III, IV e V e anti-nucleares. Resultados: Os animais imunizados mostraram progressivo decréscimo da derme papilar, atrofia de anexos, aumento no depósito dos colágenos I, III e V e aumento da expressão de TGFbeta e PDGF. Os tolerados apresentaram aumento dos anexos cutâneos e significante diminuição no depósito dos colágenos I, III e V, TGFbeta e PDGF. O grupo de imunizados e de tolerados apresentaram anticorpos anti-colágenos III e IV e antinucleares. Conclusões: A indução de tolerância nasal com Col V diminuiu o remodelamento da pele observado no modelo experimental de esclerodermia e inibiu a síntese de citocinas fibrogênicas. Portanto, a tolerância nasal com Col V pode ser uma opção terapêutica promissora para o controle do remodelamento cutâneo em pacientes com esclerodermia. / Objective: Our aim was to verify the skin remodeling and antibody production in experimental model of scleroderma in rabbits, after induction of tolerance by daily nasal administration of human type V collagen (Col V). Methods: Female New Zealand rabbits (N=12) were immunized with 1mg/ml of Col V in complete Freund\'s adjuvant, followed by more two boosters in incomplete Freund\'s adjuvant. Six immunized rabbits received daily nasal administrating of 25ug of Col V (tolerated group), started 150 days after the first immunization, and the others animals (N=6) were only immunized (immunized group). Finally a group of rabbits immunized with Freund\'s adjuvant served as control. Skin biopsies were collected at 0, 75, 120, 150 and 210 days, and stained with H&E, Masson\'s trichrome and Sirius red for morphological and morphometric analysis. Types I, III and V collagen, TGFbeta and PDGF were immunostained by immunofluorescence. The sera of animals were colleted at 0, 150 and 210 days to determine anti types I, III, IV and V collagen and antinuclear antibodies. Results: The immunized animals showed progressive decrease of papillary dermis, appendages atrophy, increase of types I, III and V collagen deposition and increased expression of TGF-beta and PDGF. The tolerated rabbits presented increase of cutaneous appendages and significant decrease of types I, III and V and TGF-beta and PDGF. Both immunized and tolerated rabbits presented anti types III and IV antibodies and antinuclear antibodies. Conclusions: Col V nasal tolerance reduced skin remodeling in experimental model of scleroderma and inhibited synthesis of fibrotic cytokines. Therefore, the nasal tolerance with type V collagen can be a promising therapeutic option to control the skin remodeling in patients with scleroderma.
449

Estudo comparativo entre a capsulorrafia com sutura simples e com âncora em quadris de coelhos / Comparative evaluation between capsulorrhaphy with simple suture and with anchor in rabbit hip joints

Garcia Filho, Fernando Cal 14 July 2010 (has links)
INTRODUÇÃO: A displasia do desenvolvimento do quadril (DDQ) é uma das patologias mais relevantes e polêmicas que acometem as crianças desde o nascimento. A anatomia tridimensional, a complexidade da articulação do quadril, o pouco conhecimento sobre o potencial de remodelação acetabular após luxação ou sub-luxação e as sequelas na marcha e na movimentação suscitam várias discussões sobre esse tema. A revisão bibliográfica a respeito dos diferentes tipos de capsulorrafia é muito pouco discutida entre os pesquisadores. Técnicas menos agressivas e que possibilitem maior resistência à recidiva da luxação após a redução cruenta devem ser pesquisadas. OBJETIVO: a presente pesquisa busca, por meio de ensaios biomecânicos, comparar as capsulorrafias com sutura simples e com âncoras, em quadris de coelhos. MATERIAL E MÉTODO: Foram utilizados 13 coelhos, 26 quadris, todos machos da raça Nova Zelândia albinos (Oryctolagus cuniculus). Inicialmente, realizamos um projeto piloto em três coelhos (06 quadris). Este experimento constou de 10 coelhos, divididos em 02 grupos: o grupo 1 submetido à capsulorrafia (quadris direito e esquerdo) com sutura simples utilizando fio absorvível de ácido poliglicólico e o grupo 2 submetido a capsulorrafia (quadris direito e esquerdo) com âncora de titânio. Após o período de quatro semanas de operados, todos animais foram submetidos à eutanásia e seus quadris congelados. Após um descongelamento prévio das peças no mesmo dia das análises biomecânicas, foram avaliados os parâmetros da rigidez (Rig), força máxima (Fmax), deformidade máxima (Dmax) e energia (E). RESULTADO: não houve diferença estatisticamente significante em relação à força no limite de proporcionalidade, rigidez e força máxima entre os grupos com sutura simples e com âncora. CONCLUSÃO: Por meio dos ensaios biomecânicos, tendo como parâmetro a rigidez (Rig), força máxima (Fmax), deformidade máxima (Dmax) e energia (E), ficou demonstrado que as capsulorrafias em quadris de coelhos com sutura simples e com âncora são semelhantes entre si. / INTRODUCTION:HDD (Hip Development Dysplasia) is one of the most important and controversial pathologies which affect children. The threedimensional anatomy and complexity of the hip joint, as well as the little understanding of the potential of acetabular reconstruction after luxation or sub-luxation and the later effects on the child\'s gait and movement, raise various points of discussion. Little literature exists about the different types of capsulorrhaphy. Techniques which are less aggressive or decrease risk of luxation after surgical reduction must be researched. OBJECTIVE: Using biomechanical studies, this research aims to compare hip capsulorrhaphy in rabbits, carried out with two different techniques: capsulorrhaphy with simple sutures and with anchors. MATERIAL AND METHOD: Thirteen New Zealand Albino (Oryctolagus cuniculus) male rabbits, twenty-six hip joints, were used. First, a pilot project was performed with three rabbits (six hip joints). The experimental group consisted of ten rabbits and was divided in two sub-groups: group 1 underwent capsulorrhaphy on both right and left hips with simple suture using polyglocolic acid absorbable thread, and group 2 underwent capsulorrhaphy with titanium anchors. After a four-week postoperation period, the animals were euthanized and the hip joints were frozen. On the same day the hip joints were unfrozen, a biomechanical study was carried out, evaluating the following parameters: rigidity, maximum force, maximum deformity and energy. RESULTS: There was no relevant statistical difference in rigidity, maximum force, maximum deformity and energy between the simple suture and anchor groups. CONCLUSION: Through biomechanical analyses, using parameters of rigidity, maximum force, maximum deformity and energy, it has been shown that a capsulorrhaphy with simple suture and with an anchor has similar results in rabbit hip joints.
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Efeitos do treinameno físico aeróbico sobre a lesão pulmonar induzida por exposição à fumaça de cigarro em camundongos C57BI6 / Aerobic exercise attenuates pulmonary alterations induced by exposure to cigarette smoke in mice

Tolêdo, Alessandra Choqueta de 06 August 2009 (has links)
O exercício aeróbio foi recentemente descrito como capaz de reduzir a função pulmonar e diminuir o risco de desenvolver DPOC entre fumantes ativos. A plausibilidade biológica da influência da atividade física sobre o declínio da função pulmonar está relacionada aos efeitos anti-inflamatórios efeitos da atividade física, que tem sido descritos em estudos experimentais. A hipótese é que haveria uma interação entre exercício aeróbio e o desenvolvimento da doença. A fim de explorar mais a fisiopatologia da DPOC induzida pela exposição à fumaça de cigarro e os efeitos do exercício no desenvolvimento do enfisema, utilizamos um modelo experimental de DPOC. C57Bl6 foram divididos em quatro grupos: Controle, Fumo, Exercício e Fumo/Exercício. Os animais dos grupos Fumo foram expostos à fumaça de cigarro por 30 minutos por dia, 5 dias por semana, durante 24 semanas. Os animais dos grupos Exercício foram treinados em intensidade moderada durante 60 minutos por dia, 5 dias por semana durante 24 semanas. Os resultados demonstraram que o treinamento físico aeróbio regular de intensidade moderada inibiu o desenvolvimento de enfisema, o aumento do total de células inflamatórias e a produção de espécies reativas de oxigênio no LBA, além do aumento na geração de óxido nítrico exalado, induzido pela exposição à fumaça do cigarro, e inibiu o aumento de 8-isoprostano e MCP1, além de aumentar a expressão da GPx, SODCuZn, TIMP1 e IL-10 por células inflamatórias na parede alveolar. O estudo também mostrou que o treinamento físico aeróbio foi capaz de inibir a diminuição da elastância pulmonar induzida pela exposição à fumaça de cigarro, mas não reduziu o aumento de colágeno no parênquima pulmonar. Estes resultados sugerem que o treinamento físico regular aeróbico de intensidade moderada pode desempenhar um papel importante durante a instalação da doença devido ao seu efeito antioxidante e antiinflamatório / Aerobic exercise was recently described as capable to reduce lung function decline and risk of developing COPD among active smokers. The biological plausibility of the influence of physical activity on the decline of lung function relies on the anti-inflammatory effects of physical activity, which have been described in experimental studies. We hypothesized there would be an interaction between aerobic exercise and development of disease. In order to further explore the physiopathology of COPD induced by exposure to cigarette smoke and the effects of exercise in development of emphysema, we used an experimental model of DPOC. C57Bl6 were divided in four groups: Control, Smoke, Exercise and Smoke/Exercise. Smoke groups were exposed to cigarette smoke for 30 minutes a day, 5 days a week, for 24 weeks. Exercise groups were trained at moderate intensity exercise for 60 minutes/day, 5 days/week for 24 weeks. The results demonstrated that regular aerobic physical training of moderate intensity inhibited alveolar distension, the increase of total inflammatory cells and production of reactive oxygen species in BAL and the increase in the generation of exhaled nitric oxide induced by exposure to cigarette smoke, and reduced the expression of 8-isoprostane and MCP1 and increased the expression of GPx, SODCuZn, TIMP1 and IL-10 by inflammatory cells in the alveolar wall. The study also showed that aerobic physical training was able to inhibit the decrease in lung elastance induced by exposure to cigarette smoke, but not the content in collagen fibers. These results suggest that regular aerobic physical training of moderate intensity may play an important role during the installation of disease due to its antioxidant and antiinflammatory effects

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