993 resultados para 840
Resumo:
O objetivo deste trabalho foi estimar a biomassa sustentável de juvenis de pirarucu Arapaima gigas (Cuvier, 1829) mantidos em tanquesrede de pequeno volume. Durante 200 dias os peixes foram estocados em quatro tanques-rede de 1 m³, cada um com biomassa inicial total de 0,84±0,14 kg (21 peixes/tanque-rede). Os tanquesrede foram colocados em um viveiro de 50 m² com renovação constante de água. Os índices do fator de condição, da conversão alimentar, do crescimento específico e do ganho de biomassa revelaram que a biomassa sustentável de juvenis de pirarucu para a criação intensiva em tanques-rede de 1 m³ foi de aproximadamente 29 kg. O comprimento alcançado pelo peixe, no espaço reduzido do tanque-rede, é um fator limitante para manter bons índices zootécnicos.
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OBJECTIVE: Standard cardiopulmonary bypass (CPB) circuits with their large surface area and volume contribute to postoperative systemic inflammatory reaction and hemodilution. In order to minimize these problems a new approach has been developed resulting in a single disposable, compact arterio-venous loop, which has integral kinetic-assist pumping, oxygenating, air removal, and gross filtration capabilities (CardioVention Inc., Santa Clara, CA, USA). The impact of this system on gas exchange capacity, blood elements and hemolysis is compared to that of a conventional circuit in a model of prolonged perfusion. METHODS: Twelve calves (mean body weight: 72.2+/-3.7 kg) were placed on cardiopulmonary bypass for 6 h with a flow of 5 l/min, and randomly assigned to the CardioVention system (n=6) or a standard CPB circuit (n=6). A standard battery of blood samples was taken before bypass and throughout bypass. Analysis of variance was used for comparison. RESULTS: The hematocrit remained stable throughout the experiment in the CardioVention group, whereas it dropped in the standard group in the early phase of perfusion. When normalized for prebypass values, both profiles differed significantly (P<0.01). Both O2 and CO2 transfers were significantly improved in the CardioVention group (P=0.04 and P<0.001, respectively). There was a slightly higher pressure drop in the CardioVention group but no single value exceeded 112 mmHg. No hemolysis could be detected in either group with all free plasma Hb values below 15 mg/l. Thrombocyte count, when corrected by hematocrit and normalized by prebypass values, exhibited an increased drop in the standard group (P=0.03). CONCLUSION: The CardioVention system with its concept of limited priming volume and exposed foreign surface area, improves gas exchange probably because of the absence of detectable hemodilution, and appears to limit the decrease in the thrombocyte count which may be ascribed to the reduced surface. Despite the volume and surface constraints, no hemolysis could be detected throughout the 6 h full-flow perfusion period.
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Several studies over the last few years have shown that newly arising (de novo) mutations contribute to the genetics of schizophrenia (SZ), autism (ASD) and other developmental disorders. The strongest evidence comes from studies of de novo Copy Number Variation (CNV), where the rate of new mutations is shown to be increased in cases when compared to controls [23, 24]. Research on de novo point mutations and small insertion-deletions (indels) has been more limited, but with the development of next-generation sequencing (NGS) technology, such studies are beginning to provide preliminary evidence that de novo single-nucleotide mutations (SNVs) might also increase risk of SZ and ASD [25, 26] Advanced paternal age is a major source of new mutations in human beings [27] and could thus be associated with increased risk for developing SZ, ASD or other developmental disorders. Indeed, advanced paternal age is found to be a risk factor for developing SZ and ASD in the offspring [28, 29] and new mutations related to advanced paternal age have been implicated as a cause of sporadic cases in several autosomal dominant diseases, some neurodevelopmental diseases, including SZ and ASD, and social functioning. New single-base substitutions occur at higher rates at males compared to females and this difference increases with paternal age. This is due to the fact that sperm cells go through a much higher number of cell divisions (~840 by the age of 50), which increases the risk for DNA copy errors in the male germ line [30] . By contrast, the female eggs (oocytes) undergo only 24 cell divisions and all but the last occur during foetal life. The aim of my project is to determine the parent-of-origin of de novo SNVs, using large samples of parent-offspring trios affected with schizophrenia (SZ). From whole exome sequencing of 618 Bulgarian proband-offspring trios affected, nearly 1000 de novo (SNVs or small indels) have been identified and from these, the parent-of-origin of at least 60% of the mutations (N=600) can be established. This project is contained in a main one that consists on the determination of the parental origin of different types of de novo mutations (SNVs, small indels and large CNVs).
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Research into the biomechanical manifestation of fatigue during exhaustive runs is increasingly popular but additional understanding of the adaptation of the spring-mass behaviour during the course of strenuous, self-paced exercises continues to be a challenge in order to develop optimized training and injury prevention programs. This study investigated continuous changes in running mechanics and spring-mass behaviour during a 5-km run. 12 competitive triathletes performed a 5-km running time trial (mean performance: ̴17 min 30 s) on a 200 m indoor track. Vertical and anterior-posterior ground reaction forces were measured every 200 m by a 5-m long force platform system, and used to determine spring-mass model characteristics. After a fast start, running velocity progressively decreased (- 11.6%; P<0.001) in the middle part of the race before an end spurt in the final 400-600 m. Stride length (- 7.4%; P<0.001) and frequency (- 4.1%; P=0.001) decreased over the 25 laps, while contact time (+ 8.9%; P<0.001) and total stride duration (+ 4.1%; P<0.001) progressively lengthened. Peak vertical forces (- 2.0%; P<0.01) and leg compression (- 4.3%; P<0.05), but not centre of mass vertical displacement (+ 3.2%; P>0.05), decreased with time. As a result, vertical stiffness decreased (- 6.0%; P<0.001) during the run, whereas leg stiffness changes were not significant (+ 1.3%; P>0.05). Spring-mass behaviour progressively changes during a 5-km time trial towards deteriorated vertical stiffness, which alters impact and force production characteristics.
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Little is known about the financial burden of individuals with depressive symptoms. This study explored that burden, using data from the Survey of Health, Ageing, and Retirement in Europe. To assess the association between depressive symptoms and the individuals' financial burden for medical care and whether they forwent medical care because of costs, logistic regressions were performed that adjusted for age, gender, marital status, education, and chronic diseases. A total of 16,696 noninstitutionalized individuals aged 50-79 years were included in the study. Individuals with depressive symptoms and those without such symptoms bore a similar financial burden. However, individuals with depressive symptoms were at increased risk of forgoing care because of costs, which may worsen their health and financial situation
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The cblC defect is the most common inborn error of vitamin B12 metabolism. Despite therapeutic measures, the long-term outcome is often unsatisfactory. This retrospective multicentre study evaluates clinical, biochemical and genetic findings in 88 cblC patients. The questionnaire designed for the study evaluates clinical and biochemical features at both initial presentation and during follow up. Also the development of severity scores allows investigation of individual disease load, statistical evaluation of parameters between the different age of presentation groups, as well as a search for correlations between clinical endpoints and potential modifying factors. RESULTS: No major differences were found between neonatal and early onset patients so that these groups were combined as an infantile-onset group representing 88 % of all cases. Hypotonia, lethargy, feeding problems and developmental delay were predominant in this group, while late-onset patients frequently presented with psychiatric/behaviour problems and myelopathy. Plasma total homocysteine was higher and methionine lower in infantile-onset patients. Plasma methionine levels correlated with "overall impression" as judged by treating physicians. Physician's impression of patient's well-being correlated with assessed disease load. We confirmed the association between homozygosity for the c.271dupA mutation and infantile-onset but not between homozygosity for c.394C>T and late-onset. Patients were treated with parenteral hydroxocobalamin, betaine, folate/folinic acid and carnitine resulting in improvement of biochemical abnormalities, non-neurological signs and mortality. However the long-term neurological and ophthalmological outcome is not significantly influenced. In summary the survey points to the need for prospective studies in a large cohort using agreed treatment modalities and monitoring criteria.
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BACKGROUND:: In 2007, leading international experts in the field of inflammatory bowel disease (IBD) recommended intravenous (IV) iron supplements over oral (PO) ones because of superior effectiveness and better tolerance. We aimed to determine the percentage of patients with IBD undergoing iron therapy and to assess the dynamics of iron prescription habits (IV versus PO). METHODS:: We analyzed anonymized data on patients with Crohn's disease and ulcerative colitis extracted from the Helsana database. Helsana is a Swiss health insurance company providing coverage for 18% of the Swiss population (1.2 million individuals). RESULTS:: In total, 629 patients with Crohn's disease (61% female) and 398 patients with ulcerative colitis (57% female) were identified; mean observation time was 31.8 months for Crohn's disease and 31.0 months for ulcerative colitis patients. Of all patients with IBD, 27.1% were prescribed iron (21.1% in males; 31.1% in females). Patients treated with steroids, immunomodulators, and/or anti-tumor necrosis factor drugs were more frequently treated with iron supplements when compared with those not treated with any medications (35.0% versus 20.9%, odds ratio, 1.94; P < 0.001). The frequency of IV iron prescriptions increased significantly from 2006 to 2009 for both genders (males: from 2.6% to 10.1%, odds ratio = 3.84, P < 0.001; females: from 5.3% to 12.1%, odds ratio = 2.26, P = 0.002), whereas the percentage of PO iron prescriptions did not change. CONCLUSIONS:: Twenty-seven percent of patients with IBD were treated with iron supplements. Iron supplements administered IV were prescribed more frequently over time. These prescription habits are consistent with the implementation of guidelines on the management of iron deficiency in IBD.
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The objective of this work was to develop, validate, and compare 190 artificial intelligence-based models for predicting the body mass of chicks from 2 to 21 days of age subjected to different duration and intensities of thermal challenge. The experiment was conducted inside four climate-controlled wind tunnels using 210 chicks. A database containing 840 datasets (from 2 to 21-day-old chicks) - with the variables dry-bulb air temperature, duration of thermal stress (days), chick age (days), and the daily body mass of chicks - was used for network training, validation, and tests of models based on artificial neural networks (ANNs) and neuro-fuzzy networks (NFNs). The ANNs were most accurate in predicting the body mass of chicks from 2 to 21 days of age after they were subjected to the input variables, and they showed an R² of 0.9993 and a standard error of 4.62 g. The ANNs enable the simulation of different scenarios, which can assist in managerial decision-making, and they can be embedded in the heating control systems.
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The central and peripheral nervous systems are involved in multiple age-dependent neurological deficits that are often attributed to alterations in function of myelinating glial cells. However, the molecular events that underlie the age-related decline of glial cell function are unknown. We used Schwann cells as a model to study biological processes affected in glial cells by aging. We comprehensively profiled gene expression of the Schwann cellrich mouse sciatic nerve throughout life, from day of birth until senescence (840 days of age). We combined the aging data with the microarray transcriptional data obtained using nerves isolated from Schwann cell-specific neuropathy-inducing mutants MPZCre/+/Lpin1fE2−3/fE2−3 , MPZCre/+/ScapfE1/fE1 and Pmp22-null mice. The majority of age related transcripts were also affected in the analyzed mouse models of neuropathy (54.4%) and in development (59.5%) indicating a high level of overlapping in implicated molecular pathways. We observed that compared to peripheral nerve development, dynamically changing expression profiles in aging have opposite (anticorrelated) orientation while they copy the orientation of transcriptional changes observed in analyzed neuropathy models. Subsequent clustering and biological annotation of dynamically changing transcripts revealed that the processes most significantly deregulated in aging include inflammatory/immune response and lipid biosynthesis/metabolism. Importantly, the changes in these pathways were also observed in myelinated oligodendrocyte-rich optic nerves of aged mice, albeit with lower magnitude. This observation suggests that similar biological processes are affected in aging glial cells in central and peripheral nervous systems, however with different dynamics. Our data, which provide the first comprehensive comparison of molecular changes in glial cells in three distinct biological conditions comprising development, aging and disease, provide not only a new inside into the molecular alterations underlying neural system aging but also identify target pathways for potential therapeutic approaches to prevent or delay complications associated with age-related and inherited forms of neuropathies. *Current address: Department of Physiology, UCSF, San Francisco, CA, USA.
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A monoclonal antibody, LAU-A1, which selectively reacts with all cells of the T-lineage, was derived from a fusion between spleen cells of a mouse immunized with paediatric thymocytes and mouse myeloma P X 63/Ag8 cells. As shown by an antibody-binding radioimmunoassay and analysis by flow microfluorometry of cells labelled by indirect immunofluorescence, the LAU-A1 antibody reacted with all six T-cell lines but not with any of the B-cell lines or myeloid cell lines tested from a panel of 17 human hematopoietic cell lines. The LAU-A1 antibody was also shown to react with the majority of thymocytes and E-rosette-enriched peripheral blood lymphocytes. Among the malignant cell populations tested, the blasts from all 20 patients with acute T-cell lymphoblastic leukemia (T-ALL) were found to react with the LAU-A1 antibody, whereas blasts from 85 patients with common ALL and 63 patients with acute myeloid leukemias were entirely negative. Examination of frozen tissue sections from fetal and adult thymuses stained by an indirect immunoperoxidase method revealed that cells expressing the LAU-A1 antigen were localized in both the cortex and the medulla. From the very broad reactivity spectrum of LAU-A1 antibody, we conclude that this antibody is directed against a T-cell antigen expressed throughout the T-cell differentiation lineage. SDS-PAGE analysis of immunoprecipitates formed by LAU-A1 antibody with detergent lysates of radiolabeled T-cells showed that the LAU-A1 antigen had an apparent mol. wt of 76,000 under non-reducing conditions. Under reducing conditions a single band with an apparent mol. wt of 40,000 was observed. Two-dimensional SDS-PAGE analysis confirmed that the 76,000 mol. wt component consisted of an S-S-linked dimeric complex. The surface membrane expression of LAU-A1 antigen on HSB-2 T-cells was modulated when these cells were cultured in the presence of LAU-A1 antibody. Re-expression of LAU-A1 antigen occurred within 24 hr after transfer of the modulated cells into antibody-free medium.
Resumo:
The central and peripheral nervous systems are involved in multiple agedependent neurological deficits that are often attributed to alterations in function of myelinating glial cells. However, the molecular events that underlie the age-related decline of glial cell function are unknown. We used Schwann cells as a model to study biological processes affected in glial cells by aging. We comprehensively profiled gene expression of the Schwann cell-rich mouse sciatic nerve throughout life, from day of birth until senescence (840 days of age). We combined the aging data with the microarray transcriptional data obtained using nerves isolated from Schwann cell-specific neuropathy-inducing mutants MPZCre/þ/Lpin1fE2-3/fE2-3, MPZCre/þ/ScapfE1/fE1 and Pmp22-null mice. A majority of age related transcripts were also affected in the analyzed mouse models of neuropathy (54.4%) and in development (59.5%) indicating a high level of overlapping in implicated molecular pathways. We observed that compared to peripheral nerve development, dynamically changing expression profiles in aging have opposite (anticorrelated) orientation while they copy the orientation of transcriptional changes observed in analyzed neuropathy models. Subsequent clustering and biological annotation of dynamically changing transcripts revealed that the processes most significantly deregulated in aging include inflammatory/ immune response and lipid biosynthesis/metabolism. Importantly, the changes in these pathways were also observed in myelinated oligodendrocyte- rich optic nerves of aged mice, albeit with lower magnitude. This observation suggests that similar biological processes are affected in aging glial cells in central and peripheral nervous systems, however with different dynamics. Our data, which provide the first comprehensive comparison of molecular changes in glial cells in three distinct biological conditions comprising development, aging and disease, provide not only a new inside into the molecular alterations underlying neural system aging but also identify target pathways for potential therapeutical approaches to prevent or delay complications associated with age-related and inherited forms of neuropathies.
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O objetivo deste trabalho foi realizar caracterização física e avaliar o efeito de substratos à base de serragem e dois recipientes no crescimento de mudas de cacaueiro. O delineamento experimental foi em blocos casualizados, em esquema fatorial 2 x 4 x 2. Os tratamentos foram obtidos da combinação de serragens originadas de dois locais: municípios de Una e Camacan, no Estado da Bahia, quatro proporções (v:v) de serragem e areia: 1:0; 8:1; 4:1 e 2:1 e dois recipientes de crescimento (tubetes de 288 cm³ e sacos de polietileno de 840 cm³). Antes do plantio, amostras dos substratos foram retiradas para análises físicas. Foram usadas miniestacas de 4 a 6 cm de comprimento do clone Trinidad Select Hybrid (TSH 1188). Inicialmente, as miniestacas foram tratadas na base com AIB 6.000 mg kg-1, em seguida foram inseridas em tubetes preenchidos com os substratos e mantidas em câmara de nebulização. Após quarenta dias, as miniestacas foram retiradas da câmara e transferidas para crescimento, em casa de vegetação, onde parte foi mantida nos respectivos tubetes e outra transplantada em sacos de polietileno de 840 cm³ preenchidos com os mesmos tratamentos. Após cinco meses, em casa de vegetação, as mudas foram avaliadas quanto à altura da planta, diâmetro do caule, massa da matéria seca da parte aérea e das raízes, número de folhas e área foliar das plantas. Na análise física dos substratos, verificou-se que a distribuição do tamanho de partículas foi diferenciada entre as serragens e a proporção de areia. As densidades seca, úmida e de partícula aumentaram, enquanto o teor de matéria orgânica e a porosidade total foram reduzidos pela adição de areia às serragens. O transplante de miniestacas enraizadas de cacaueiro, clone TSH 1188, para sacos com substrato preparado com serragem coletada no município de Una-BA, nas proporções serragem:areia 4:1 e 2:1, possibilitou maior crescimento das plantas, sendo,portanto, recomendados para produção de mudas.
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Clines in life history traits, presumably driven by spatially varying selection, are widespread. Major latitudinal clines have been observed, for example, in Drosophila melanogaster, an ancestrally tropical insect from Africa that has colonized temperate habitats on multiple continents. Yet, how geographic factors other than latitude, such as altitude or longitude, affect life history in this species remains poorly understood. Moreover, most previous work has been performed on derived European, American and Australian populations, but whether life history also varies predictably with geography in the ancestral Afro-tropical range has not been investigated systematically. Here, we have examined life history variation among populations of D. melanogaster from sub-Saharan Africa. Viability and reproductive diapause did not vary with geography, but body size increased with altitude, latitude and longitude. Early fecundity covaried positively with altitude and latitude, whereas lifespan showed the opposite trend. Examination of genetic variance-covariance matrices revealed geographic differentiation also in trade-off structure, and QST -FST analysis showed that life history differentiation among populations is likely shaped by selection. Together, our results suggest that geographic and/or climatic factors drive adaptive phenotypic differentiation among ancestral African populations and confirm the widely held notion that latitude and altitude represent parallel gradients.