411 resultados para INACTIVITY
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Ao longo dos últimos anos a reforma dos sistemas prisionais e a eficácia da reinserção social têm vindo a integrar as agendas políticas dos governos dos países europeus. Esta reforma deriva de vários problemas e carências com que se debatem os diversos sistemas prisionais, nomeadamente a sobrelotação, o ambiente propício à violência, o consumo de drogas, a inactividade do recluso e o elevado índice de reincidência criminal. Porém, qualquer reforma que se venha a delinear compreende matérias muito complexas que vão desde os direitos humanos aos recursos humanos e financeiros, imperativos legais, bem como a conciliação entre a punição e a ressocialização. Estas matérias não dependem apenas da vontade política, mas igualmente da sociedade, a qual ainda ergue barreiras à reinserção, tratando o ex-recluso como um excluído da sociedade. Neste sentido, os estudos universitários constituem um elemento chave na procura de soluções para esta problemática, na medida em que se servem das várias áreas do saber para de alguma forma contribuir com possíveis soluções, tendo em vista a melhoria de todo o sistema prisional e a eficácia da reinserção social. Esta dissertação tem assim como objectivo apresentar os principais modelos de sistemas prisionais adoptados em países europeus e efectuar uma comparação entre estes. Pretende-se retirar os aspectos mais relevantes de cada sistema e que têm contribuído para a melhoria das condições dos reclusos e do aumento da reinserção destes na sociedade, bem como na diminuição da taxa de reincidência criminal.
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RESUMO: Na sociedade contemporânea a diabetes tipo 2 e a obesidade estão a aumentar exponencialmente, representando um grave problema de saúde pública. De acordo com a IDF “A diabetes e a obesidade são o principal problema de saúde pública do século XXI’. Para além destas duas patologias, a prevalência de esteatose hepática não-alcoólica (NAFLD), entre a população obesa e diabética, é de cerca de 90%. O aumento da obesidade, diabetes e NAFLD tem uma forte correlação com o aumento do consumo de gorduras e açúcares, acompanhado de um decréscimo acentuado da actividade física. A obesidade, diabetes e NAFLD tem sido escrupolosamente investigada mas as terapêuticas disponíveis continuam a ser muito limitadas. Tendo em conta o número crescente e alarmante de obesos e diabéticos o conhecimento detalhado da patofisiologia da obesidade, diabetes e NAFLD, tendo em vista a necessidade extrema de desenvolvimento de novas estratégias terapêuticas, é da mais elevada urgência. O fígado é reconhecido como um orgão primordial no controlo da homeostase. No estado pós-prandial, o fígado converte a glucose em glicogénio e lípidos. Em contraste, no estado de jejum, o fígado promove a produção de glucose. Sistemas neuronais e hormonais, bem como o estado metabólico do fígado, controlam de forma muito precisa a alternância entre os diferentes substratos metabólicos, dependente do estado prandial. A insulina tem um papel central no controlo do metabolismo energético no fígado; se, por um lado, inibe a produção hepática de glucose e corpos cetónicos, por outro, promove a glicólise e a lipogénese. O metabolismo energético no fígado é também regulado por vários factores de transcrição e co-reguladores que, por sua vez, são regulados pela insulina, glucagina e outras hormonas metabólicas. Em conjunto, todos estes factores e reguladores vão controlar de forma muito estreita a gluconeogénese, a β-oxidação e a lipogénese, no fígado. Para além dos já conhecidos reguladores do metabolismo hepático, novas moléculas têm sido estudadas como tendo um papel fundamental na regulação do metabolismo energético no fígado. Qualquer desequilíbrio no metabolismo hepático vai contribuir para a insulino-resistência, NAFLD e diabetes tipo 2. O principal objectivo do trabalho de investigação aqui apresentado é o contributo para o estudo detalhado da patogénese da diabetes e obesidade, num contexto de dietas ricas em açúcares e gorduras, e com a perspectiva de explorar novas estratégias terapêuticas. Os objectivos específicos deste trabalho eram: primeiro, determinar se o tratamento com glutationo (GSH) e óxido nítrico (NO) era suficiente para melhorar a insulino-resistência associada ao elevado consumo de sacarose; segundo, determinar o papel da Rho-kinase 1 (ROCK1) na regulação do metabolismo hepático da glucose e dos lípidos; e terceiro, estudar o efeito do metilsulfonilmetano (MSM) em doenças metabólicas associadas à obesidade. Na primeira parte deste trabalho de investigação foram utilizados ratos Wistar machos sujeitos a uma dieta rica em sacarose (HS). Tal como esperado, estes animais apresentavam insulino-resistência e hiperinsulinémia. A dieta HS levou ao aumento dos níveis hepáticos de NO e ao decréscimo dos níveis de GSH no fígado. Em jejum, a administração intraportal de GSH e NO, a animais saudáveis promoveu um aumento significativo da sensibilidade à insulina. Também nestes animais, a administração intravenosa de S-nitrosotióis, compostos orgânicos que contém um grupo nitroso acoplado a um átomo de enxofre de um tiol, promoveu o aumento significativo da sensibilidade à insulina. Pelo contrário, em animais sujeitos à dieta HS, as doses padrão de GSH + NO e de S-nitrosotióis não conseguiram promover o aumento da sensibilidade à insulina. No entanto, ao aumentar a dose de S-nitrosotióis administrados por via intravenosa, foi possível observar o aumento da sensibilidade à insulina dependente da dose, indicando um possível papel dos S-nitrosotióis como sensibilizadores de insulina. O estudo detalhado do papel dos S-nitrosotióis na via de sinalização da insulina revelou que há um aumento da fosforilação do receptor da insulina (IR) e da proteína cinase B (Akt), sugerindo um efeito dos S-nitrosotióis nesta via de sinalização. Os resultados apresentados nesta primeira parte sugerem que os S-nitrosotióis promovem a correcta acção da insulina, podendo vir a ser importantes alvos terapêuticos. Na segunda parte deste trabalho de investigação utilizámos murganhos, com uma delecção específica da ROCK1 no fígado, e sujeitos a uma dieta rica em lípidos (HFD). Foi possível concluir que a ausência da ROCK1 no fígado previne a obesidade, melhora a sensibilidade à insulina e protege contra a esteatose hepática. A ausência de ROCK1 no fígado levou a um decréscimo significativo da expressão génica de genes associados à lipogénese, com uma diminuição acentuada do fluxo metabólico associado a esta via. Pelo contrário, a sobreexpressão de ROCK1, exclusivamente no fígado, promove a insulino-resistência e a esteatose hepática no contexto de obesidade induzida pela dieta. Para além disto, a delecção da ROCK1 no fígado de animais obesos e diabéticos, os murganhos deficientes em leptina, corroborou os dados obtidos no primeiro modelo animal, com a franca melhoria da hiperglicémia, hiperinsulinémia e esteatose hepática. Os dados que compõem esta parte do trabalho de investigação sugerem que a ROCK1 tem um papel crucial na regulação do metabolismo lipídico. Na terceira e última parte deste trabalho de investigação foi investigado o efeito do composto metilsulfunilmetano (MSM), um composto organosulfúrico naturalmente presente em plantas e utilizado também como suplemento dietético, em murganhos obesos e insulino-resistentes, por exposição a uma dieta rica em lípidos (DIO). O tratamento com MSM melhorou a insulino-resistência e protegeu contra a esteatose hepática. O conteúdo hepático em triglicéridos e colesterol também diminuíu de forma significativa nos animais DIO sujeitos ao tratamento com MSM, bem como a expressão génica associada à lipogénese. Para além disto, o tratamento com MSM levou a uma diminuição da expressão génica associada à inflamação. De realçar que o tratamento com MSM levou a uma melhoria do perfil hematopoiético destes animais, tanto na medula óssea como no sangue. Para comprovar o efeito benéfico do MSM na obesidade e insulino-resistência utilizámos murganhos deficientes no receptor da leptina, e por isso obesos e diabéticos, tendo observado um perfil semelhante ao obtido para murganhos sujeitos a uma dieta rica em lípidos e tratados com MSM. Concluímos, através dos dados recolhidos, que o MSM como suplemento pode ter efeitos benéficos na hiperinsulinémia, insulino-resistência e inflamação que caracterizam a diabetes tipo 2. Em resumo, os dados obtidos neste trabalho de investigação mostram que os S-nitrosotióis podem ter um papel importante como sensibilizadores da insulina, promovendo um aumento da sensibilidade à insulina num contexto de dietas ricas em sacarose. Para além disto, estudos in vitro, sugerem que os S-nitrosotióis regulam, especificamente, a via de sinalização da insulina. Este trabalho teve também como objectivo o estudo da ROCK1 como regulador do metabolismo da glucose e dos lípidos no fígado. Através do estudo de animais com uma delecção ou uma sobreexpressão da ROCK1 no fígado mostrou-se que esta tem um papel crucial na patogénese da obesidade e diabetes tipo 2, especificamente através do controlo da lipogénese de novo. Finalmente, foi também objectivo deste trabalho, explorar o efeito do MSM em animais DIO e deficientes em leptina. O tratamento com MSM protege de forma evidente contra a obesidade e insulino-resistência, com especial enfâse para a capacidade que esta molécula demonstrou ter na protecção contra a inflamação. Em conjunto os vários estudos aqui apresentados mostram que tanto os S-nitrosotióis como a ROCK1 têm um papel na patogénese da obesidade e diabetes tipo 2 e que a utilização de MSM como suplemento às terapêuticas convencionais pode ter um papel no tratamentos de doenças metabólicas.-------------------------------ABSTRACT: In modern western societies type 2 diabetes and obesity are increasing exponentially, representing a somber public concern. According to the International Diabetes Federation (IDF) ‘Diabetes and Obesity are the biggest public health challenges of the 21st century’. Aside from these the prevalence of nonalcoholic fatty liver disease (NAFLD), among the diabetic and obese population, is as high as 90%. It is now well established that the increase in obesity, diabetes and NAFLD strongly correlates with an increase in fat and sugar intake in our diet, alongside physical inactivity. The pathogenesis of obesity, diabetes and NAFLD has been thoroughly studied but the treatment options available are still narrow. Considering the alarming number in the obese and diabetic population the complete understanding of the pathogenesis, keeping in mind that new therapeutic strategies need to be attained, is of the highest urgency. The liver has been well established as a fundamental organ in regulating whole-body homeostasis. In the fed state the liver converts the glucose into glycogen and lipids. Conversely, in the fasted state, glucose will be produced in the liver. Neuronal and hormonal systems, as well as the hepatic metabolic states, tightly control the fast to fed switch in metabolic fuels. Insulin has a central role in controlling hepatic energy metabolism, by suppressing glucose production and ketogenesis, while stimulating glycolysis and lipogenesis. Liver energy metabolism is also regulated by various transcription factors and coregulators that are, in turn, regulated by insulin, glucagon and other metabolic hormones. Together, these regulators will act to control gluconeogenesis, β-oxidation and lipogenesis in the liver. Aside from the well-established regulators of liver energy metabolism new molecules are being studied has having a role in regulating hepatic metabolism. Any imbalance in the liver energy metabolism is a major contributor to insulin resistance, NAFLD and type 2 diabetes. The overall goal of this research work was to contribute to the understanding of the pathogenesis of diabetes and obesity, on a setting of high-sucrose and high-fat diets, and to explore potential therapeutic options. The specific aims were: first, to determine if treatment with glutathione (GSH) and nitric oxide (NO) was sufficient to ameliorate insulin resistance induced by high-sucrose feeding; second, to determine the physiological role of rho-kinase 1 (ROCK1) in regulating hepatic and lipid metabolism; and third, to study the effect of methylsulfonylmethane (MSM) on obesity-linked metabolic disorders. In the first part of this research work we used male Wistar rats fed a high-sucrose (HS) diet. As expected, rats fed a HS diet were insulin resistant and hyperinsulinemic. HS feeding increased hepatic levels of NO, while decreasing GSH. In fasted healthy animals administration of both GSH and NO, to the liver, was able to increase insulin sensitivity. Intravenous administration of S-nitrosothiols, organic compounds containing a nitroso group attached to the sulfur atom of a thiol, in fasted control animals also increased insulin sensitivity. Under HS feeding the standard doses of GSH + NO and S-nitrosothiols were unable to promote an increase in insulin sensitivity. However, the intravenous administration of increasing concentrations of S-nitrosothiols was able to restore insulin sensitivity, suggesting that S-nitrosothiols have an insulin sensitizing effect. Investigation of the effect of S-nitrosothiols on the insulin signaling pathway showed increased phosphorylation of the insulin receptor (IR) and protein kinase B (Akt), suggesting that S-nitrosothiols may have an effect on the insulin signaling pathway. Together, these data showed that S-nitrosothiols promote normal insulin action, suggesting that they may act as potential pharmacological tools. In the second part of this research work we used liver-specific ROCK1 knockout mice fed a high-fat (HF) diet. Liver-specific deletion of ROCK1 prevented obesity, improved insulin sensitivity and protected against hepatic steatosis. Deficiency of ROCK1 in the liver caused a significant decrease in the gene expression of lipogenesis associated gene, ultimately leading to decreased lipogenesis. Contrariwise, ROCK1 overexpression in the liver promoted insulin resistance and hepatic steatosis in diet-induced obesity. Furthermore, liver-specific deletion of ROCK1 in obese and diabetic mice, the leptin-deficient mice, improved the typical hyperglycemia, hyperinsulinemia and liver steatosis. Together, these data identify ROCK1 as a crucial regulator of lipid metabolism. In the third and final part of this research work we investigated the effect of MSM, an organosulfur compound naturally found in plants and used as a dietary supplement, on diet-induced obese (DIO) and insulin resistant mice. MSM treatment ameliorated insulin resistance and protected against hepatosteatosis. Hepatic content in triglycerides and cholesterol was significantly decreased by MSM treatment, as well as lipogenesis associated gene expression. Furthermore, MSM treated mice had decreased inflammation associated gene expression in the liver. Importantly, FACS analysis showed that MSM treatment rescued the inflammatory hematopoietic phenotype of DIO mice in the bone marrow and the peripheral blood. Moreover, MSM treatment of the obese and diabetic mice, the leptin-deficient mice, resulted in similar effects as the ones observed for DIO mice. Collectively, these data suggest that MSM supplementation has a beneficial effect on hyperinsulinemia, insulin resistance and inflammation, which are often found in type 2 diabetes. In conclusion, this research work showed that S-nitrosothiols may play a role as insulin sensitizers, restoring insulin sensitivity in a setting of high-sucrose induced insulin resistance. Furthermore, in vitro studies suggest that S-nitrosothiols specifically regulate the insulin signaling pathway. This research work also investigated the role of hepatic ROCK1 in regulation of glucose and lipid metabolism. Using liver-specific ROCK 1 knockout and ROCK1 overexpressing mice it was shown that ROCK1 plays a role in the pathogenesis of obesity and type 2 diabetes, specifically through regulation of the de novo lipogenesis pathway. Finally, this research work aimed to explore the effect of MSM in DIO and leptin receptor-deficient mice. MSM strongly protects against obesity and insulin resistance, moreover showed a robust ability to decrease inflammation. Together, the individual studies that compose this dissertation showed that S-nitrosothiols and ROCK1 play a role in the pathogenesis of obesity and type 2 diabetes and that MSM supplementation may have a role in the treatment of metabolic disorders.
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ABSTRACT - Background: From a public health perspective, the study of socio-demographic factors related to physical activity is important in order to identify subgroups for intervention programs. Purpose: This study also aimed to identify the prevalence and the socio-demographic correlates related with the achievement of recommended physical activity levels. Methods: Using data from the European Social Survey round 6, physical activity and socio-demographic characteristics were collected from 39278 European adults (18271 men, 21006 women), aged 18-64 years, from 28 countries in 2012. Meeting physical activity guidelines was assessed using World Health Organization criteria. Results: 64.50% (63.36% men, 66.49% women) attained physical activity recommended levels. The likelihood of attaining physical activity recommendations was higher in age group of 55-64 years (men: OR=1.22, p<0.05; women: OR=1.66, p<0.001), among those who had completed high school (men: OR=1.28, p<0.01; women: OR=1.26, p<0.05), among those who lived in rural areas (men: OR=1.20, p<0.001; women: OR=1.10, p<0.05), and among those who had 3 or more people living at home (men: OR=1.40, p<0.001; women: OR=1.43, p<0.001). On the other hand, attaining physical activity recommendations was negatively associated with being unemployed (men: OR=0.70, p<0.001; women: OR=0.87, p<0.05), being a student (men: OR=0.56, p<0.001; women: OR=0.64, p<0.01), being a retired person (men: OR=0.86, p<0.05) and with having a higher household income (OR=0.80, p<0.001; women: OR=0.81, p<0.01). Conclusion: This research helped clarify that, as the promotion of physical activity is critical to sustain health and prevent disease, socio-demographic factors are important to consider when planning the increase of physical activity.
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Tese de doutoramento em Estudos da Criança (área de especialização em Formação de Professores).
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OBJECTIVE - A population-based prospective study was analysed to: a) determine the prevalence of hypertension; b) investigate the clustering of other cardiovascular risk factors and c) verify whether older differed from younger adults in the pattern of clustering. METHODS - The data comprised a representative sample of the population of Bambuí, Brazil. Multiple logistic regression was used to investigate the independent association between hypertension and selected factors. RESULTS - A total of 820 younger adults (82.5%) and 1494 older adults (85.9%) participated in this study. The overall prevalence of hypertension was 24.8% (SE=1.4 %), being higher in women (26.9±1.5%) than in men (22.0± 1.7%) (p=0.033). Hypertension was positively and significantly associated with physical inactivity, overweight, hypercholesterolemia hyperglycemia and hypertriglyceridemia. The coexistence of hypertension with 4 or more of these risk factors occurred 6 times more than expected by chance, after adjusting for age and sex (OR=6.3; 95%CI: 3.4-11.9). The pattern of risk factor clustering in hypertensive individuals differed with age. CONCLUSION - Our results reinforce the need to increase detection and treatment of hypertension and to approach patients' global risk profiles.
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Background: Hypertension is a public health problem, considering its high prevalence, low control rate and cardiovascular complications. Objective: Evaluate the control of blood pressure (BP) and cardiovascular outcomes in patients enrolled at the Reference Center for Hypertension and Diabetes, located in a medium-sized city in the Midwest Region of Brazil. Methods: Population-based study comparing patients enrolled in the service at the time of their admission and after an average follow-up of five years. Participants were aged ≥18 years and were regularly monitored at the Center up to 6 months before data collection. We assessed demographic variables, BP, body mass index, risk factors, and cardiovascular outcomes. Results: We studied 1,298 individuals, predominantly women (60.9%), and with mean age of 56.7±13.1 years. Over time, there was a significant increase in physical inactivity, alcohol consumption, diabetes, dyslipidemia, and excessive weight. As for cardiovascular outcomes, we observed an increase in stroke and myocardial revascularization, and a lower frequency of chronic renal failure. During follow-up, there was significant improvement in the rate of BP control (from 29.6% to 39.6%; p = 0.001) and 72 deaths, 91.7% of which were due to cardiovascular diseases. Conclusion: Despite considerable improvements in the rate of BP control during follow-up, risk factors worsened and cardiovascular outcomes increased.
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Background: Physical stress echocardiography is an established methodology for diagnosis and risk stratification of coronary artery disease in patients with physical capacity. In obese (body mass index ≥ 30 kg/m2) the usefulness of pharmacological stress echocardiography has been demonstrated; however, has not been reported the use of physical stress echocardiography in this growing population group. Objective: To assess the frequency of myocardial ischemia in obese and non-obese patients undergoing physical stress echocardiography and compare their clinical and echocardiographic differences. Methods: 4,050 patients who underwent treadmill physical stress echocardiography were studied according to the Bruce protocol, divided into two groups: obese (n = 945; 23.3%) and non-obese (n = 3,105; 76.6%). Results: There was no difference regarding gender. Obese patients were younger (55.4 ± 10.9 vs. 57.56 ± 11.67) and had a higher frequency of hypertension (75.2% vs. 57, 2%; p < 0.0001), diabetis mellitus (15.2% vs. 10.9%; p < 0.0001), dyslipidemia (59.5% vs 51.9%; p < 0.0001), family history of coronary artery disease (59.3% vs. 55.1%; p = 0.023) and physical inactivity (71.4% vs. 52.9%, p < 0.0001). The obese had greater aortic dimensions (3.27 vs. 3.14 cm; p < 0.0001), left atrium (3.97 vs. 3.72 cm; p < 0.0001) and the relative thickness of the ventricule (33.7 vs. 32.8 cm; p < 0.0001). Regarding the presence of myocardial ischemia, there was no difference between groups (19% vs. 17.9%; p = 0.41). In adjusted logistic regression, the presence of myocardial ischemia remained independently associated with age, female gender, diabetes and hypertension. Conclusion: Obesity did not behave as a predictor of the presence of ischemia and the physical stress echocardiography. The application of this assessment tool in large scale sample demonstrates the feasibility of the methodology, also in obese.
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Abstract Background: Due to the importance of coronary artery disease (CAD), continuous investigation of the risk factors (RFs) is needed. Objective: To evaluate the prevalence of RFs for CAD in cities in Rio Grande do Sul State, and compare it with that reported in a similar study conducted in the same cities in 2002. Methods: Cross-sectional study on 1,056 healthy adults, investigating the prevalence and absolute and relative frequencies of the following RFs for CAD: obesity, systemic arterial hypertension (SAH), dyslipidemias, smoking, sedentary lifestyle, diabetes mellitus, and family history, as well as age and sex. Data was collected in 19 cities, host of the Offices of the Regional Coordinators of Health, as in the 2002 study. Results: Twenty-six percent of the sample consisted of older adults and 57% were women. The prevalence of sedentary lifestyle was 44%, history family 50%, smoking 23%, overweight/obesity 68%, dyslipidemia (high cholesterol levels) 43%, SAH 40%, and diabetes 11%. When compared to the 2002 study, the prevalence of active smoking and sedentary behavior decreased, whereas the prevalence of hypertension, dyslipidemia and obesity increased. Obesity is the most prevalent RF in women, and SAH the most prevalent in men. Conclusions: The prevalence of RFs for CAD in Rio Grande do Sul State remains high. Hypertension, obesity and dyslipidemia are still prevalent and require major prevention programs. Smoking and physical inactivity have decreased in the state, suggesting the efficacy of related campaigns.
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Abstract Background: Acute coronary syndrome (ACS) is one of the main causes of morbidity and mortality in the modern world. A sedentary lifestyle, present in 85% of the Brazilian population, is considered a risk factor for the development of coronary artery disease. However, the correlation of a sedentary lifestyle with cardiovascular events (CVE) during hospitalization for ACS is not well established. Objective: To evaluate the association between physical activity level, assessed with the International Physical Activity Questionnaire (IPAQ), with in-hospital prognosis in patients with ACS. Methods: Observational, cross-sectional, and analytical study with 215 subjects with a diagnosis of ACS consecutively admitted to a referral hospital for cardiac patients between July 2009 and February 2011. All volunteers answered the short version of the IPAQ and were observed for the occurrence of CVE during hospitalization with a standardized assessment conducted by the researcher and corroborated by data from medical records. Results: The patients were admitted with diagnoses of unstable angina (34.4%), acute myocardial infarction (AMI) without ST elevation (41.4%), and AMI with ST elevation (24.2%). According to the level of physical activity, the patients were classified as non-active (56.3%) and active (43.7%). A CVE occurred in 35.3% of the cohort. The occurrence of in-hospital complications was associated with the length of hospital stay (odds ratio [OR] = 1.15) and physical inactivity (OR = 2.54), and was independent of age, systolic blood pressure, and prior congestive heart failure. Conclusion: A physically active lifestyle reduces the risk of CVE during hospitalization in patients with ACS.
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In this paper the author describes a very interesting case of union of two homologous chromosomes of the scorpion Tityus bahiensis just by the opposite extremities. The two normal pairs of chromosomes behave as ordinarily, the members of each pair showing at times a slight disturbance in their regular parallelism. The complex chromosome, on the contrary, behaves itself as if it were devoid of kinetochores, that is, it does not orient like normal chromosomes nor reveal any kind of active movement. The fusion of the chromosomes has resulted from terminal breakage at the opposite ends, the correspondig fragments having been found unpaired in a cell in which two pairs of chromosomes were present. Consequently, the compound chromosome, like the normal ones, is provided with a kinetochore at each one of the free ends. Being thus a centric chromosome its behavior, or more exactly, its kinetic inactivity may be compared with that of the monovalents found elsewhere in meioses. It is due o the failure of a partner. The fusion of two homologous chromosomes has transformed them into a new chromosomal unit in whose corresponding parts the ability of pairing was entirely abolished. This result is in full contradiction with the theory of a point-to point attraction between homologous chromosomes attributed to particular power of the genes, since, if genes really exist, being placed in their original loci, they would promote the union side by side of the members of the compound chromosome. If an attraction loci-to-loci should prevail the compound chromosome would be bent as in Fig. 8, C or form a ring similar to the loops observed in the inverted segment of sailvary chromosomes of Drosophila, as represented in the Fig. 8, D and this, in accordance with the order of the loci resulting from an union of corresponding or opposite ends of the fused chromosomes, as indicated in the Fig, 8 A and B. The evidence in hand points to a fusion by non homologous extremities. The expected rings, however, have never been found in metaphase plates. From this fact the author concludes that there is no point-to-point attraction between chromosomes, a conclusion in full agreement with the behavior of Hemipteran chromosomes which, in spite of geing composed of two equivalent halves do not bend in order to adjust the corresponding loci. (Cf. the papers on Hemiptera published by the author in this volume).
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Particular aspects of the meiosis of two species of Hemiptera, namely Megalotomus pallescens (Stal) (Coriscidae) and Jadera sanguinolenta (Fabr.); (Corizidae) are described and discussed in this paper. Megalotomus pallescens This species has primary spermatocytes provided with 7 autosomal tetrads plus a single sex chromosome. The X is smaller than the autosomes and may be found either in the periphery of the circle formed by the autosomal tetrads or in the center together with the m-tetrad which always occupies this position. The X chromosome - In the primary spermatocytes this element, which is tetradiform, orients itself parallelly to the spindle axis and divides transversely by its median constriction. In the secondary spermatocytes it passes undivided to one pole. The m-chromosomes - These chromosomes have been frequently found in close association with the sex chromosome in nuclei wich have passed the diffuse stage, a fact which was considered as affording some evidence in support of the idea /developed by the present writer in another paper with regard to the origin of the m-chromosomes from the sex chromosome. Formation of tetrads - Tetrads appear at first as irregular areas of reticular structure, becoming later more and more distinct. Then, two chromosomal strands very loose and irregular in outline, connected whit each other by several transverse filaments, begin to develop in each area. Growing progressively shorter, thicker and denser, these strands soon give origin to typical Hemiptera tetrads. Jadera sanguinolenta Spermatogonia of this species have 13 chromosomes, that is, 10 autosomes, 2 m-chromosomes and one sex chromosome, one pair of autosomes being much larger than the rest. Chromosomes move toward the poles with both ends looking to them. Primary spermatocytes show 6 tetrads and a single X. The sex chromossome in the first division of the spermatocytes divides as if it was a tetrad, passing undivided to one pole in the second division. In the latter it does not orient, being found anywhere in the cells. Its most common situation in anaphase corresponds therefore to precession. Tetrads are formed here in an entirely different way : the bivalents as they become distinct in the nuclei which came out. of the diffuse stage they appear in form of two thin threads united only at the extremities, an aspect which may better be analized in the larger bivalent. Up from this stage the formation of the tetrads is a mere process of shortening and thickening of both members of the pair. Due to the fact that the paired chromosomes are well separated from each other throughout their entire lenght, the author concluded that chiasmata, if present, are accumulated at the very ends of the bivalents. If no chiasmata have been at all formed, then, what holds together the corresponding extremities must be a strong attraction developed by the kinetochores. If one interprets the bivalents represented in the figures 17-21 as formed by four chromatids paired by one of the ends and united by the opposite one, then the question of the diffuse attachment becomes entirely disproved since it is exactly by the distal extremities that the tetrads later will be connected with the poles. In the opinion of the present writer the facts referred to above are one of the best demonstration at hand of the continuity of the paired threads and at the same time of the dicentricity of Hemiptera chromosomes. In view of the data hitherto collected by the author the behavior of the sex chromosome of the Hemiptera whose males are of the XO type may be summarized as follows: a) The sex chromosome in the primary metaphase appears longitudinally divided, without transverse constriction. It is oriented with the extremities in the plane of the equator and its chromatids separate by the plane of division. (Euryophthalmus, Protenor). In the second division the sex chromosome, provided as it is with an active kinetochore at each end, orients itself with its lenght parallelly to the spindle axis and passes undivided to one pole (Protenor?), or loses to the other pole a centric end (Euryophthalmus) In the latter case it has to become dicentric by means of a longitudinal spliting beginning at the kinetochore. b) The sex chromosome in the primary metaphase is tetradiform, that is, it is provided with a longitudinal split and a median transverse constriction. Orients with its length paral lelly to the spindle axis (what is probably due to the kinetochores being not yet divided) and divides transversely. (Corizas hyalinus, Megalotomus pallescens). in the secondary metaphase the sex chromosome which turned to be dicentric in consequence of a longitudinal spliting initiated in the kineto chore, orients perpendicularly to the equatorial plane and without losing anyone of its extremities passes undivided to one pole (Megalotomus). Or, distending between both poles passes to one side, in which case it loses one of its ends to the other side. (Corizas hyalinus). c) The very short sex chromosome in the first division of the spermatocytes orients in the same manner aa the tetrads and divides transversely. In the second division, due to the inactivity o the inetochore, it remains monocentric and motionless anywhere in the cell, finishing by being enclosed in the nearer nucleus. In the secondary telophase it recuperates its dicentricity at the same time as the autosomal chromatids. (Jadera sanguinolenta, Diactor bilineatus). d) The sex chromosome in the first division orients in the equador with its longitudinal axis parallelly to the spindle axis passing integrally to one pole or, distending itself between the anaphase plates, loses one of its ends to the opposite pole. In this case it becomes dicentric in the prometaphase of the second division, behaving in this division as the autossomes. It thus divides longitudnally. (Pachylis laticomis, Pachylis pharaonis).
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The present paper colligates the notions acquired in previous investigations, already published, and new observations upon diseases of the psittacidae, liable to be confused with psittacosis of parrots. The author calls attention to the indifference with regard to this question shown by investigators, even by those who dealt with the study of this disease on the occasion of the latest outbreak of psittacosis, in flagrant contrast with the researches upon the alterations induced by pathogenic agents of other diseases transmissible to man, when these agents pass through animals or when the latter are depositaries of the virus. This remark considerably enhances the importance of the presence paper from a hygienic and epidemiologic point of view, representing moreover a contribution to general knowledge and to veterinary medicine. The researches carried out since the appearance of the latest outbreak of psittacosis,-which occurred simultaneously with an epizooty in parrots lodged in aviary of the park of Agua Branca (Directory of Animal Industry of the State São Paulo)-led to the verification of the frequent existence in these animals of various diseases liable to be confused with psittacosis. These diseases are due to two kinds of pathogenic agents: virus and bacteria. In the first group there are to be found the diseases occasioned by the virus of human psittacosis, discovered by Western, Bedson and Simpson, and the disease me with in parrots coming from traders in S. Paulo. The infections by bacteria of the genus Salmonella and by those of other genera belong to the second group. As differential characters of the two infections due to virus, delineated on the strength of notions drawn from a detailed experimental study and from the literature on this subject, the following are given: ¹ Samples of our virus were sent, for comparison, to various investigators of psittacosis. Amongst them, Prof. M. Rivers acceded to our request; he found its nature to be different from that of the virus of psittacosis studiedby him. We are very much obliged to him for the attention he paid to this verification. Virus of psittacosis - Infectiousness: man, monkey, rabbit, mouse, hen, canary. Neurotropic affinity. Inclusions: small, protoplasmic. Exsiccation: the virus has good power of preservation. Symptoms: inactivity, drowsiness, frequent diarrhoea, oculo-nasal discharge and cough, coma. Duration: 4 to 5 days. Bodily lesions: congestion of intestines, splenomegaly. Virus of S. Paulo - Infects only psittacidae, particularly those of the genus Amazona. No localization in the nervous system. Large, nuclear. Is rapidly destroyed. Inactivity, inappetency, adynamia (drooping of the wings, indifference, leaning its beak against the bars of the cage in order not to fall down); profuse diarrhoea, of whitish stools, at times enterorrhagia; prolonged coma. 2 to 8 days. Foci of yellowish necrosis in liver, spleen and lung. At times, congestion of intestines. Characteristic features common to the two viruses.-They act in great dilutions, filter through tight candles though being partly retained, are preserved under glycerine or Bedson's solution, are stable at 55°C. heat and are destroyed by physical and chemical agents. Both virus diseases are very seldom met with in psittacidae: only once, amongst numberless sick parrots, the author met with a disease of the virus differring from that of psittacosis. This disease, greatly transmissible to man, ought to be more frequent, if it were common in parrots. On the contrary, bacteria cause diseases in these animals with great frequency, presenting variable characters, from a severe epizootic form, rapidly mortal, to ambulatory or silent forms, for the most part developing towards a cure or assuming a chronic character. Amongst the bacteria which cause the infection of this group the salmonellae predominate and amongst them the bacterium discovered by Nocard, as well as a species which in the course of this study is characterized under the name of Salmonella nocardi. The author believes that in the epizooty from which Nocard isolated his bacterium there was association of the virus-disease inducing the epizooty of that epoch in Paris with the bacterial disease, as must have happened in Argentina, where the disease was transmitted to man, and Santillan, according to Barros, isolated from the sick parrots bacteria of the genus Salmonella. The diseases of the two groups, that due to virus and that due to bacteria, are differentiated: Virus-diseases - Evolution: rapid, nearly always followed by death. Symptoms: sadness, profuse diarrhoea, of whitish stools, at times enterorrhagia, complete inappetency, adynamia, indifference, prolonged coma. Clinical forms: acute and subacute. Lesions: Foci of necrosis in liver and spleen without cellular reaction around the focus, yellow liver, multiple serositis. Presence of protoplasmic or nuclear granulations. Bacteriology: Complete lack or inconstant presence of bacteria in the organs and blood. Infectiousness of the organs and blood after filtration: positive. Bacterial diseases - Varies from one week to a month or more, not always fatal. Sadness, partial inappetency, tremblings, intensive thirst, mucous or mucosanguineous diarrhoea, lack of adynamia (reacts to stimulations and moves well at any time of the disease, though showing little disposition to locomotion), soiling of feathers. Frustrate, acute, subacute and chronic. Hepatic and intestinal cogestion, foci of necrosis in liver, spleen and lung with cellular reaction around the focus. Lack of granulations. Constant presence of bacteria in the organs and blood. Negative. The analysis of the litterature shows that the characteristic features of the diseases in parrots referred to parrot psittacosis, more frequently approach the bacterial diseases here described of these animals, a hypothesis which is reinforced by the observation of the greater frequency of infections...
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A selective and differencial medium was developed for the isolation of Acinetobacter genus bacteria. This Acinobacter Agar Medium (p.H + 7.4) contains in grams per litre: thiotone, 10; yeast extract, 3; naC1, 5; saccharose, 10; mannitol, 10; sodium citrate, 0.5; sodium desoxycholate, 0.1; crystal violet, 0.00025; phenol red, 0.04 and agar-agar 15. This medium has the advantage of inhibiting the growth of cocci and Gram-positive bacilli, by the use of sodium citrate and sodium desoxycholate associated with the crystal violet; and of differentiating the Gram-negative bacilli from the Enterobacteriaceae, through the fermentative activity upon the saccharose and/or mannitol, contrasting with the complete inactivity of the Acinetobacter genus bacteria over those substances.
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[Contents] Introduction. Objectives. Methodology. Results. Characteristics of the sample. Substance use (Psychoactive substances, Performance-enhancing substances). Profile of sportive adolescents using substances. Mixed substance use. Other factors related to substance use. Inactivity. Conclusions. References. Annexes. Annex 1. Questionnaire. Annex 2. Sample weighting procedure. Annex 3. Sports type.
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COPD is associated with some skeletal muscle dysfunction which contributes to a poor exercise tolerance. This dysfunction results from multiple factors: physical inactivity, corticosteroids, smoking, malnutrition, anabolic deficiency, systemic inflammation, hypoxia, oxidative stress. Respiratory rehabilitation is based on exercise training and allows patients with COPD to experience less dyspnoea, and to improve their exercise tolerance and quality of life. Not all patients, however, benefit from rehabilitation. Acknowledging the different factors leading to muscular dysfunction allows one to foresee new avenues to improve efficacy of exercise training in COPD.