Neoproterozoic glacial deposits from the Aracuai orogen, Brazil: Age, provenance and correlations with the Sao Francisco craton and West Congo belt

Glacigenic diamictite successions of the Macaubas Group are widespread in the western domain of the Aracuai orogen, east of the Sao Francisco craton (Brazil). Diamictites also occur on this craton and in the African counterpart of the Aracuai orogen, the West Congo belt. Detrital zircon grains from the matrix of diamictites and sandstones from the Macaubas Group were dated by the U-Pb SHRIMP technique. The geochronological study sets the maximum depositional age of the glacial diamictites at 900 Ma, and indicates multiple sources for the Macaubas basin with ages ranging from 900 to 2800 Ma. Sm-Nd T-DM model ages, determined on whole rock samples, range from 1.8 Ga to 2.5 Ga and get older up-section. Comparison of our data with those from the cratonic area suggest that these glacial deposits can be correlated to the Jequitai and Carrancas diamictites in the Sao Francisco craton, and to the Lower Mixtite Formation of the West Congolian Group, exposed in Africa. The 900-1000 Ma source is most probably represented by the Zadinian-Mayumbian volcanic rocks and related granites from the West Congo belt. However, one of the most voluminous sources, with ages in the 1.1-1.3 Ga interval, has not been detected in the Sao Francisco-Congo craton. Possible sources for these grains could occur elsewhere in Africa, or possibly from within the Brasilia Belt in western central Brazil. (C) 2011 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

Prevalence and risk factors of Hepatitis C virus infection in Brazil, 2005 through 2009: a cross-sectional study

Abstract Background Hepatitis C chronic liver disease is a major cause of liver transplant in developed countries. This article reports the first nationwide population-based survey conducted to estimate the seroprevalence of HCV antibodies and associated risk factors in the urban population of Brazil. Methods The cross sectional study was conducted in all Brazilian macro-regions from 2005 to 2009, as a stratified multistage cluster sample of 19,503 inhabitants aged between 10 and 69 years, representing individuals living in all 26 State capitals and the Federal District. Hepatitis C antibodies were detected by a third-generation enzyme immunoassay. Seropositive individuals were retested by Polymerase Chain Reaction and genotyped. Adjusted prevalence was estimated by macro-regions. Potential risk factors associated with HCV infection were assessed by calculating the crude and adjusted odds ratios, 95% confidence intervals (95% CI) and p values. Population attributable risk was estimated for multiple factors using a case–control approach. Results The overall weighted prevalence of hepatitis C antibodies was 1.38% (95% CI: 1.12%–1.64%). Prevalence of infection increased in older groups but was similar for both sexes. The multivariate model showed the following to be predictors of HCV infection: age, injected drug use (OR = 6.65), sniffed drug use (OR = 2.59), hospitalization (OR = 1.90), groups socially deprived by the lack of sewage disposal (OR = 2.53), and injection with glass syringe (OR = 1.52, with a borderline p value). The genotypes 1 (subtypes 1a, 1b), 2b and 3a were identified. The estimated population attributable risk for the ensemble of risk factors was 40%. Approximately 1.3 million individuals would be expected to be anti-HCV-positive in the country. Conclusions The large estimated absolute numbers of infected individuals reveals the burden of the disease in the near future, giving rise to costs for the health care system and society at large. The known risk factors explain less than 50% of the infected cases, limiting the prevention strategies. Our findings regarding risk behaviors associated with HCV infection showed that there is still room for improving strategies for reducing transmission among drug users and nosocomial infection, as well as a need for specific prevention and control strategies targeting individuals living in poverty.

Water transfer from São Francisco river to semiarid northeast of Brazil: technical data, environmental impacts, survey of opinion about the amount to be transferred

The transposition of the São Francisco River is considered one of the greatest engineering works in Brazil of all time since it will cross an extensive agricultural region of continental dimensions, involving environmental impacts, water, soil, irrigation, water payment and other multidisciplinary themes. Taking into account its importance, this subject was incorporated into a discipline of UFSCar (Federal University of São Carlos - Brazil) named "Pollution and Environmental Impacts". It was noted strong reaction against the project, even before the presentation. To allow a critical analysis, the first objective was to compile the main technical data and environmental impacts. The second objective was to detect the three most important aspects that cause reaction, concluding for the following reasons: assumption that the volume of water to be transferred was much greater than it actually is proposed in the project; lack of knowledge about similar project already done in Brazil; the idea that the artificial canal to be built was much broader than that proposed by the project. The participants' opinion about "volume to be transferred" was raised quantitatively four times: 2-undergraduate students; 1-graduate; 1-outside community. The average resulted 14 times larger than that proposed in the project, significant according to t-test. It was concluded that the reaction to water transfer project is due in part to the ignorance combined with a preconceived idea that tend to overestimate the magnitude of environmental impacts.

Oxidative Stress and Modification of Renal Vascular Permeability Are Associated with Acute Kidney Injury during P. berghei ANKA Infection

Malaria associated-acute kidney injury (AKI) is associated with 45% of mortality in adult patients hospitalized with severe form of the disease. However, the causes that lead to a framework of malaria-associated AKI are still poorly characterized. Some clinical studies speculate that oxidative stress products, a characteristic of Plasmodium infection, as well as proinflammatory response induced by the parasite are involved in its pathophysiology. Therefore, we aimed to investigate the development of malaria-associated AKI during infection by P. berghei ANKA, with special attention to the role played by the inflammatory response and the involvement of oxidative stress. For that, we took advantage of an experimental model of severe malaria that showed significant changes in the renal pathophysiology to investigate the role of malaria infection in the renal microvascular permeability and tissue injury. Therefore, BALB/c mice were infected with P. berghei ANKA. To assess renal function, creatinine, blood urea nitrogen, and ratio of proteinuria and creatininuria were evaluated. The products of oxidative stress, as well as cytokine profile were quantified in plasma and renal tissue. The change of renal microvascular permeability, tissue hypoxia and cellular apoptosis were also evaluated. Parasite infection resulted in renal dysfunction. Furthermore, we observed increased expression of adhesion molecule, proinflammatory cytokines and products of oxidative stress, associated with a decrease mRNA expression of HO-1 in kidney tissue of infected mice. The measurement of lipoprotein oxidizability also showed a significant increase in plasma of infected animals. Together, our findings support the idea that products of oxidative stress, as well as the immune response against the parasite are crucial to changes in kidney architecture and microvascular endothelial permeability of BALB/c mice infected with P. berghei ANKA.

The influence of "C-factor" and light activation technique on polymerization contraction forces of resin composite

Objectives: This study evaluated the influence of the cavity configuration factor ("C-Factor") and light activation technique on polymerization contraction forces of a Bis-GMA-based composite resin (Charisma, Heraeus Kulzer). Material and Methods: Three different pairs of steel moving bases were connected to a universal testing machine (Emic DL 500): groups A and B - 2x2 mm (CF=0.33), groups C and D - 3x2 mm (CF=0.66), groups E and F - 6x2 mm (CF=1.5). After adjustment of the height between the pair of bases so that the resin had a volume of 12 mm(3) in all groups, the material was inserted and polymerized by two different methods: pulse delay (100 mW/cm(2) for 5 s, 40 s interval, 600 mW/cm(2) for 20 s) and continuous pulse (600 mW/cm(2) for 20 s). Each configuration was light cured with both techniques. Tensions generated during polymerization were recorded by 120 s. The values were expressed in curves (Force(N) x Time(s)) and averages compared by statistical analysis (ANOVA and Tukey's test, p<0.05). Results: For the 2x2 and 3x2 bases, with a reduced C-Factor, significant differences were found between the light curing methods. For 6x2 base, with high C-Factor, the light curing method did not influence the contraction forces of the composite resin. Conclusions: Pulse delay technique can determine less stress on tooth/restoration interface of adhesive restorations only when a reduced C-Factor is present.

Voriconazole, Combined with Amphotericin B, in the Treatment for Pulmonary Cryptococcosis Caused by C. neoformans (Serotype A) in Mice with Severe Combined Immunodeficiency (SCID)

Cryptococcosis is a subacute or chronic systemic mycosis with a cosmopolitan nature, caused by yeast of the genus Cryptococcus neoformans. The model of systemic cryptococcosis in mice with severe combined immunodeficiency (SCID) is useful for immunological and therapeutic study of the disease in immunodeficient hosts. Amphotericin B, fluconazole and flucytosine are the drugs most commonly used to treat cryptococcosis. Voriconazole is a triazole with high bioavailability, large distribution volume, and excellent penetration of the central nervous system. The objective of this study was to evaluate treatment with amphotericin B (AMB), voriconazole (VRC), and AMB, used in combination with VRC, of experimental pulmonary cryptococcosis in a murine model (SCID). The animals were inoculated intravenously (iv) with a solution containing 3.0 x 10(5) viable cells of C. neoformans ATCC 90112, (serotype A). Treatments were performed with amphotericin B (1.5 mg/kg/day), voriconazole (40.0 mg/kg/day) and AMB (1.5 mg/kg/day) combined with VRC (40.0 mg/kg/day); began 1 day after the initial infection; were daily; and lasted 15 days. Evaluations were performed using analysis of the survival curve and isolation of yeast in the lung tissue. There was a significant increase in survival in groups treated with AMB combined with VRC, compared with the untreated group and groups receiving other treatments (P < 0.05). In the group treated only with VRC and AMB combined with VRC, there was a significant reduction (P < 0.05) in the isolation of C. neoformans in lung tissue. Amphotericin B combined with voriconazole may be an effective alternative to increasing survival and may reduce yeast in the lung tissue of mice with pulmonary cryptococcosis and SCID.

Phylogeographic Analysis of HIV-1 Subtype C Dissemination in Southern Brazil

The HIV-1 subtype C has spread efficiently in the southern states of Brazil (Rio Grande do Sul, Santa Catarina and Parana). Phylogeographic studies indicate that the subtype C epidemic in southern Brazil was initiated by the introduction of a single founder virus population at some time point between 1960 and 1980, but little is known about the spatial dynamics of viral spread. A total of 135 Brazilian HIV-1 subtype C pol sequences collected from 1992 to 2009 at the three southern state capitals (Porto Alegre, Florianopolis and Curitiba) were analyzed. Maximum-likelihood and Bayesian methods were used to explore the degree of phylogenetic mixing of subtype C sequences from different cities and to reconstruct the geographical pattern of viral spread in this country region. Phylogeographic analyses supported the monophyletic origin of the HIV-1 subtype C clade circulating in southern Brazil and placed the root of that clade in Curitiba (Parana state). This analysis further suggested that Florianopolis (Santa Catarina state) is an important staging post in the subtype C dissemination displaying high viral migration rates from and to the other cities, while viral flux between Curitiba and Porto Alegre (Rio Grande do Sul state) is very low. We found a positive correlation (r(2) = 0.64) between routine travel and viral migration rates among localities. Despite the intense viral movement, phylogenetic intermixing of subtype C sequences from different Brazilian cities is lower than expected by chance. Notably, a high proportion (67%) of subtype C sequences from Porto Alegre branched within a single local monophyletic sub-cluster. These results suggest that the HIV-1 subtype C epidemic in southern Brazil has been shaped by both frequent viral migration among states and in situ dissemination of local clades.

Sesquiterpene Lactones with Anti-Hepatitis C Virus Activity Using Molecular Descriptors

Hepatitis C is a worldwide public health problem. The available therapies are limited by their partial effectiveness and with meaningful side-effects. Sesquiterpene lactones (SLs) are a group of natural products with a wide variety of chemical structures and biological activities associated. There are few studies about the influence of the molecular structure of SLs for the anti-hepatitis C virus activity. In the present work, SLs are investigated in a subgenomic RNA replicon assay system and were analyzed using multiple linear regression along with self-organizing maps with DRAGON descriptors in order to identify the structural requirements for their biological activity and to predict the inhibitory potency of SLs. Characteristics such as stereochemistry and electronic effects demonstrated to be important for their anti-HCV activity, and the SOM produced a clear separation betwenn active and inactive compounds. Therefore, it is possible to use this map as a filter for virtual screening to predict the anti-HCV activity of SLs.

Brain Pathways Involved in the Modulatory Effects of Noradrenaline in Lateral Septal Area on Cardiovascular Responses

We have previously reported that stimulation of alpha-1 adrenoceptors by noradrenaline (NA) injected into the lateral septal area (LSA) of anaesthetized rats causes pressor and bradycardic responses that are mediated by acute vasopressin release into the circulation through activation of the paraventricular nucleus (PVN). Although the PVN is the final structure of this pathway, the LSA has no direct connections with the PVN, suggesting that other structures may connect these areas. To address this issue, the present study employed c-Fos immunohistochemistry to investigate changes caused by NA microinjection into the LSA in neuronal activation in brain structures related to systemic vasopressin release. NA microinjected in the LSA caused pressor and bradycardic responses, which were blocked by intraseptal administration of alpha-1 adrenoceptor antagonist (WB4101, 10 nmol/200 nL) or systemic V-1 receptor antagonist (dTyr(CH2)5(Me)AVP, 50 mu g/kg). NA also increased c-Fos immunoreactivity in the prelimbic cortex (PL), infralimbic cortex (IL), dorsomedial periaqueductal gray (dmPAG), bed nucleus of the stria terminalis (BNST), PVN, and medial amygdala (MeA). No differences in the diagonal band of Broca, cingulate cortex, and dorsolateral periaqueductal gray (dlPAG) were found. Systemic administration of the vasopressin receptor antagonist dTyr AVP (CH2)5(Me) did not change the increase in c-Fos expression induced by intra-septal NA. This latter effect, however, was prevented by local injection of the alpha-1 adrenoceptor antagonist WB4101. These results suggest that areas such as the PL, IL, dmPAG, BNST, MeA, and PVN could be part of a circuit responsible for vasopressin release after activation of alpha-1 adrenoceptors in the LSA.

Testosterone Induces Vascular Smooth Muscle Cell Migration by NADPH Oxidase and c-Src-Dependent Pathways

Testosterone has been implicated in vascular remodeling associated with hypertension. Molecular mechanisms underlying this are elusive, but oxidative stress may be important. We hypothesized that testosterone stimulates generation of reactive oxygen species (ROS) and migration of vascular smooth muscle cells (VSMCs), with enhanced effects in cells from spontaneously hypertensive rats (SHRs). The mechanisms (genomic and nongenomic) whereby testosterone induces ROS generation and the role of c-Src, a regulator of redox-sensitive migration, were determined. VSMCs from male Wistar-Kyoto rats and SHRs were stimulated with testosterone (10(-7) mol/L, 0-120 minutes). Testosterone increased ROS generation, assessed by dihydroethidium fluorescence and lucigenin-enhanced chemiluminescence (30 minutes [SHR] and 60 minutes [both strains]). Flutamide (androgen receptor antagonist) and actinomycin D (gene transcription inhibitor) diminished ROS production (60 minutes). Testosterone increased Nox1 and Nox4 mRNA levels and p47phox protein expression, determined by real-time PCR and immunoblotting, respectively. Flutamide, actinomycin D, and cycloheximide (protein synthesis inhibitor) diminished testosterone effects on p47phox. c-Src phosphorylation was observed at 30 minutes (SHR) and 120 minutes (Wistar-Kyoto rat). Testosterone-induced ROS generation was repressed by 3-(4-chlorophenyl) 1-(1,1-dimethylethyl)-1H-pyrazolo[3,4-day]pyrimidin-4-amine (c-Src inhibitor) in SHRs and reduced by apocynin (antioxidant/NADPH oxidase inhibitor) in both strains. Testosterone stimulated VSMCs migration, assessed by the wound healing technique, with greater effects in SHRs. Flutamide, apocynin, and 3-(4-chlorophenyl) 1-(1,1-dimethylethyl)-1H-pyrazolo[3,4-day] pyrimidin-4-amine blocked testosterone-induced VSMCs migration in both strains. Our study demonstrates that testosterone induces VSMCs migration via NADPH oxidase-derived ROS and c-Src-dependent pathways by genomic and nongenomic mechanisms, which are differentially regulated in VSMCs from Wistar-Kyoto rats and SHRs. (Hypertension. 2012; 59: 1263-1271.). Online Data Supplement

Upregulation of soluble and membrane-bound human leukocyte antigen G expression is primarily observed in the milder histopathological stages of chronic hepatitis C virus infection

Chronic hepatitis C virus (HCV) infection is a worldwide health problem that may evolve to cirrhosis and hepatocellular carcinoma. Incompletely understood immune system mechanisms have been associated with impaired viral clearance. The nonclassical class I human leukocyte antigen G (HLA-G) molecule may downregulate immune system cell functions exhibiting well-recognized tolerogenic properties. HCV genotype was analyzed in chronic HCV-infected patients. Because HLA-G expression may be induced by certain viruses, we evaluated the presence of HLA-G in the liver microenvironment obtained from 89 biopsies of patients harboring chronic HCV infection and stratified according to clinical and histopathological features. Overall, data indicated that HCV genotype 1 was predominant, especially subgenotype 1a, with a prevalence of 87%. HLA-G expression was observed in 45(51%) liver specimens, and it was more frequent in milder stages of chronic hepatitis (67.4%) than in moderate (27.8%; p = 0.009) and severe (36.0%; p = 0.021) stages of the disease. Altogether, these results suggest that the expression of HLA-G in the context of HCV is a complex process modulated by many factors, which may contribute to an immunologic environment favoring viral persistence. However, because the milder forms predominantly expressed HLA-G, a protective role of this molecule may not be excluded. (C) 2012 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

Risk factors for hepatitis C virus infection in Inland Brazil: An analysis of pooled epidemiological sectional studies

In order to assess the contribution of different parenteral routes as risk exposure to the hepatitis C virus (HCV), samples from nine surveys or cross-sectional studies conducted in two Brazilian inland regions were pooled, including a total of 3,910 subjects. Heterogeneity among the study results for different risk factors was tested and the results were shown to be homogeneous. Anti-HCV antibodies were observed in 241 individuals, of which 146 (3.7%, 95% CI?=?3.24.4) had HCV exposure confirmed by immunoblot analysis or PCR test. After adjustment for relevant variables, a correlation between confirmed HCV exposure and injection drug use, tattooing, and advance age was observed. In a second logistic model that included exposures not searched in all nine studies, a smaller sample was analyzed, revealing an independent HCV association with past history of surgery and males who have sex with other males, in addition to repeated injection drug use. Overall, these analyses corroborate the finding that injection drug use is the main risk factor for HCV exposure and spread, in addition to other parenteral routes. J. Med. Virol. 84:756762, 2012. (C) 2012 Wiley Periodicals, Inc.

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.

Management of diabetes mellitus and associated cardiovascular risk factors in Brazil – the Brazilian study on the practice of diabetes care

Abstract Background The Brazilian Study on the Practice of Diabetes Care main objective was to provide an epidemiological profile of individuals with type 1 and 2 diabetes mellitus (DM) in Brazil, concerning therapy and adherence to international guidelines in the medical practice. Methods This observational, cross-sectional, multicenter study collected and analyzed data from individuals with type 1 and 2 DM attending public or private clinics in Brazil. Each investigator included the first 10 patients with type 2 DM who visited his/her office, and the first 5 patients with type 1 DM. Results A total of 1,358 patients were analyzed; 375 (27.6%) had type 1 and 983 (72.4%) had type 2 DM. Most individuals were women, Caucasian, and private health care users. High prevalence rates of hypertension, dyslipidemia and central obesity were observed, particularly in type 2 DM. Only 7.3% and 5.1% of the individuals with types 1 and 2 DM, respectively, had optimal control of blood pressure, plasma glucose and lipids. The absence of hypertension and female sex were associated with better control of type 1 DM and other cardiovascular risk factors. In type 2 DM, older age was also associated with better control. Conclusions Female sex, older age, and absence of hypertension were associated with better metabolic control. An optimal control of plasma glucose and other cardiovascular risk factors are obtained only in a minority of individuals with diabetes. Local numbers, compared to those from other countries are worse.

Petrology of Gameleira potassic lamprophyres, São Francisco Craton

Gameleira lamprophyres are dykes and mafic microgranular enclaves associated with the shoshonitic Gameleira monzonite. This association belongs to the Paleoproterozoic alkaline magmatism from Serrinha nucleus, northeast Brazil. The liquidus paragenesis is diopside, pargasite, apatite and mica. Reverse zoning was identified in the groundmass alkali feldspar and was related to the undercooling of lamprophyric magma during the emplacement, with high growth rate of pargasite/edenite inducing disequilibrium between feldspars and liquid. Chemical data indicate that the lamprophyres are basic rocks (SiO2 < 48 wt%), with alkaline character (Na2O + K2O > 3 wt%) and potassic signature (K2O/Na2O ≈ 2). High contents of MgO and Cr are consistent with a signature of a primary liquid, and such concentrations, as well as Al, K, P, Ba, Ni- and light rare earth elements, are consistent with an olivine-free metasomatic mantle source enriched in amphibole, clinopyroxene and apatite. By contrast, the ultrapotassic lamprophyres from Morro do Afonso, contemporaneous alkaline ultrapotassic magmatism in Serrinha nucleus, were probably produced by melting of a clinopyroxene-phlogopite-apatite enriched-source. The identification of different mineral paragenesis in the source of potassic and ultrapotassic lamprophyres from Serrinha nucleus can contribute to the understanding of the mantle heterogeneities and tectonic evolution of this region.