Effect of Angiotensin(1-7) on Heart Function in an Experimental Rat Model of Obesity

Aim: Obesity is a risk factor for the development of cardiovascular diseases. Recently it was shown that overexpression of the Mas-receptor antagonist angiotensin(1-7) could prevent from diet-induced obesity. However, it remained unclear whether diet-induced obesity and angiotensin(1-7) overexpression might also have effects on the cardiovascular system in these rats. Methods:Twenty three male Sprague Dawley rats were fed with standard chow (SD+chow, n = 5) or a cafeteria diet (SD+CD, n = 6) for 5 months. To investigate the effect of angiotensin(1-7) transgenic rats, expressing an angiotensin(1-7)-producing fusion protein in testis were used. These transgenic rats also received a 5 month's feeding period with either chow (TGR+chow, n = 6) or cafeteria diet (TGR+CD, n = 6), respectively. Hemodynamic measurements (pressure-volume loops) were carried out to assess cardiac function and blood pressure. Subsequently, hearts were explanted and investigated according to the Langendorff technique. Furthermore, cardiac remodeling in these animals was investigated histologically. Results:After 5 months cafeteria diet feeding rats showed a significantly increased body weight, which could be prevented in transgenic rats. However, there was no effect on cardiac performance after cafeteria diet in non-transgenic and transgenic rats. Moreover, overexpression of angiotensin(1-7) deteriorated cardiac contractility as indicated by impaired dp/dt. Furthermore, histological analysis revealed that cafeteria diet led to myocardial fibrosis in both, control and transgenic rats and this was not inhibited by an overproduction of angiotensin(1-7). Conclusion:These results indicate that an overexpression of circulating angiotensin(1-7) prevents a cafeteria diet-induced increase in body weight, but does not affect cardiac performance in this experimental rat model of obesity. Furthermore, overexpression of angiotensin(1-7) alone resulted in an impairment of cardiac function

Do health systems delay the treatment of poor children? A qualitative study of child deaths in rural Tanzania.

Child mortality remains one of the major public-health problems in Tanzania. Delays in receiving and accessing adequate care contribute to these high rates. The literature on public health often focuses on the role of mothers in delaying treatment, suggesting that they contact the health system too late and that they prefer to treat their children at home, a perspective often echoed by health workers. Using the three-delay methodology, this study focus on the third phase of the model, exploring the delays experienced in receiving adequate care when mothers with a sick child contact a health-care facility. The overall objective is to analyse specific structural factors embedded in everyday practices at health facilities in a district in Tanzania which cause delays in the treatment of poor children and to discuss possible changes to institutions and social technologies. The study is based on qualitative fieldwork, including in-depth interviews with sixteen mothers who have lost a child, case studies in which patients were followed through the health system, and observations of more than a hundred consultations at all three levels of the health-care system. Data analysis took the form of thematic analysis. Focusing on the third phase of the three-delay model, four main obstacles have been identified: confusions over payment, inadequate referral systems, the inefficient organization of health services and the culture of communication. These impediments strike the poorest segment of the mothers particularly hard. It is argued that these delaying factors function as 'technologies of social exclusion', as they are embedded in the everyday practices of the health facilities in systematic ways. The interviews, case studies and observations show that it is especially families with low social and cultural capital that experience delays after having contacted the health-care system. Reductions of the various types of uncertainty concerning payment, improved referral practices and improved communication between health staff and patients would reduce some of the delays within health facilities, which might feedback positively into the other two phases of delay

Evidence of multidecadal salinity variability in the eastern tropical North Atlantic

Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 21 (2006): PA3010, doi:10.1029/2005PA001257.Ocean circulation and global climate are strongly influenced by seawater density, which is itself controlled by salinity and temperature. Although adequate instrumental sea-surface temperature (SST) records exist for most of the surface oceans over the past 100-150 years, records of salinity really only exist for the last 40-50 years. Here we show that longer proxy records from corals (Siderastrea radians) in the eastern tropical North Atlantic are dominated by multi-decadal variations in salinity which are correlated with the relationship between SST and the North Atlantic Oscillation (NAO) over the course of the 20th century. The data reveal an increase in eastern tropical North Atlantic salinity of +0.5 psu between about 1950-1990. Rather than a monotonic secular increase, as indicated by some instrumental records, the pre-instrumental coral proxy records presented here suggest that salinity in the tropical North Atlantic is periodic on a decadal to multi-decadal scale

Effect of arbuscular mycorrhizal (AM) colonization on terpene emission and content of Artemisia annua L.

Plant roots interact with a wide variety of rhizospheric microorganisms, including bacteria and the symbiontic arbuscular mycorrhizal (AM) fungi. The mycorrhizal symbiosis represents a series of complex feedbacks between plant and fungus regulated by their physiology and nutrition. Despite the widespread distribution and ecological significance of AM symbiosis, little is known about the potential of AM fungi to affect plant VOC metabolism. The purpose of this study was to investigate whether colonization of plant roots by AM fungi and associated soil microorganisms affects VOC emission and content of Artemisia annua L. plants (Asteraceae). Two inoculum types were evaluated: one consisted of only an arbuscular mycorrhizal (AM) fungus species (Glomus spp.), and the other was a mixture of different Glomus species and associated soil bacteria. Inoculated plants were compared with non-inoculated plants and with plants supplemented with extra phosphorus (P) to obtain plants of the same size as mycorrhizal plants, thus excluding potentially-confounding mycorrhizal effects on shoot growth. VOC emissions of Artemisia annua plants were analyzed by leaf cuvette sampling followed by off-line measurements with pre-concentration and gas chromatography mass spectrometry (GC-MS). Measurements of CO2 and H2O exchanges were conducted simultaneously. Several volatile monoterpenes were identified and characterized from leaf emissions of Artemisia annua L. by GC-MS analysis. The main components identified belong to different monoterpene structures: alpha-pinene, beta-pinene, camphor, 1,8-cineole, limonene, and artemisia ketone. A good correlation between monoterpene leaf concentration and leaf emission was found. Leaf extracts included also several sesquiterpenes. Total terpene content and emission was not affected by AM inoculation with or without bacteria, while emission of limonene and artemisia ketone was stimulated by this treatment. No differences were found among treatments for single monoterpene content, while accumulation of specific sesquiterpenes in leaves was altered in mycorrhizal plants compared to control plants. Growth conditions seemed to have mainly contributed to the outcome of the symbiosis and influenced the magnitude of the plant response. These results highlight the importance of considering the below-ground interaction between plant and soil for estimating VOC emission rates and their ecological role at multitrophic level

A teoria da história como hermenêutica da historiografia: uma interpretação de Do Império à República, de Sérgio Buarque de Holanda

O presente texto oferece uma interpretação de Do Império à República, o livro de Sérgio Buarque de Holanda que reconta a história política brasileira da segunda metade do século XIX. Baseando-se em conceitos desenvolvidos pelo teórico da história Jörn Rüsen, o artigo detém-se particularmente em três aspectos do referido livro: os artefatos teóricos que presidem a interpretação da crise da Monarquia brasileira, os padrões narrativos que dão suporte à constituição de sentido sobre essa experiência do passado, bem como o contexto atual de orientação que serviu de parâmetro de significado/sentido à interpretação e à representação. Esta análise pretende ilustrar que a teoria da história é não só um meio para explorar abstratamente as complexas questões ligadas à produção do conhecimento histórico, mas também uma ferramenta para a obtenção de imagens concretas acerca da prática intelectual dos historiadores profissionais

In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs

Comment in Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016] Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016] In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016] US oncologists call for government regulation to curb drug price rises. [BMJ. 2015

Crowdsourcing hypothesis tests: Making transparent how design choices shape research results

To what extent are research results influenced by subjective decisions that scientists make as they design studies? Fifteen research teams independently designed studies to answer fiveoriginal research questions related to moral judgments, negotiations, and implicit cognition. Participants from two separate large samples (total N > 15,000) were then randomly assigned to complete one version of each study. Effect sizes varied dramatically across different sets of materials designed to test the same hypothesis: materials from different teams renderedstatistically significant effects in opposite directions for four out of five hypotheses, with the narrowest range in estimates being d = -0.37 to +0.26. Meta-analysis and a Bayesian perspective on the results revealed overall support for two hypotheses, and a lack of support for three hypotheses. Overall, practically none of the variability in effect sizes was attributable to the skill of the research team in designing materials, while considerable variability was attributable to the hypothesis being tested. In a forecasting survey, predictions of other scientists were significantly correlated with study results, both across and within hypotheses. Crowdsourced testing of research hypotheses helps reveal the true consistency of empirical support for a scientific claim.</div

Plasma lipid profiles discriminate bacterial from viral infection in febrile children

Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics

Plasma lipid profiles discriminate bacterial from viral infection in febrile children

Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection ar