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991.
In Brazil, the treatment of hepatitis C virus (HCV) infection is funded by the national public health system (SUS). To evaluate treatment results in the state of Mato Grosso, central Brazil, we have consulted the files of the office of the State Department of Health responsible for supplying such medications. We obtained information on 232 treatments of 201 patients who underwent treatment in or prior to 2008. The study was conducted by reviewing medical records, making telephone calls and interviewing the assistant physicians. Thirty-nine patients (19.4%) had cirrhosis and HCV genotype 1 predominated (64.3%). Excluding patients with comorbidities or treatment without ribavirin we analysed 175 treatments (sustained virologic response occurred in 32.6% of cases). Twenty-six of these 175 were retreatments and the sustained virological response (SVR) rate among them was 30.8%; the SVR rate was 32.9% among those receiving treatment for the first time. The SVR rate of genotype 1 patients was 27.8%, whereas it was 37.5% in non-1 genotype patients. The adjusted multivariate analysis showed association of SVR with the absence of cirrhosis [odds ratio (OR): 7.7; confidence interval (CI) 95%: 2.5, 33.3], the use of pegylated interferon (OR: 5.8; CI 95%: 1.5, 21.4), non-1 genotype (OR: 5.3; CI 95%: 1.7, 16.7) and uninterrupted treatment (OR: 9.0; CI 95%: 3.3, 45.4). The SVR rates were similar to those found in other Brazilian studies about HCV, but lower than those found in national and international clinical trials. These data suggest that the treatments of chronic hepatitis C that are made available by SUS does not, under normal conditions, work as well as the original controlled studies indicated. 相似文献
992.
Brain-Derived Neurotrophic Factor Levels in Women with Postpartum Affective Disorder and Suicidality
RT Pinheiro KA Pinheiro FM da Cunha Coelho L de Ávila Quevedo M Gazal RA da Silva M Giovenardi AB Lucion DO de Souza LV Portela JP Oses 《Neurochemical research》2012,37(10):2229-2234
Our aim was to investigate serum brain-derived neurotrophic factor (BDNF) levels in postpartum women, according to the presence of postpartum affective disorder (PPAD) and suicidality. A cross-sectional study was carried out with women between 45 and 90?days after delivery. PPAD (depression, manic and mixed episode) and suicide risk were assessed using the Mini International Neuropsychiatric Interview. BDNF was assessed using a commercial ELISA kit. Linear regression was used for multivariate analyses. A hundred ninety women participated in the study, 15.3?% had PPAD, 7.4?% showed PPAD with suicide risk. BDNF levels were lower in subjects with three or more Stressful Life Events (P?=?0.01). The serum BDNF levels of women with PPAD presenting suicide risk were significantly lower than those of women without suicide risk (1.50?±?1.38 and 2.33?±?1.28?ng/ml, P?=?0.02). Clinicians should enquire postpartum women about their history of stressful life events, PPAD, and suicidality. This study shows the potential role of BDNF in the neurobiology of the association of PPAD and suicidality. 相似文献
993.
994.
Fernanda L. S. Sebastianes Nuria Cabedo Noureddine El Aouad Angela M. M. P. Valente Paulo T. Lacava João L. Azevedo Aline A. Pizzirani-Kleiner Diego Cortes 《Current microbiology》2012,65(5):622-632
Endophytic fungi are considered a rich source of active compounds resulting from their secondary metabolism. Fungi from marine environment grow in a habitat with unique conditions that can contribute to the activation of metabolic pathways of synthesis of different unknown molecules. The production of these compounds may support the adaptation and survival of the fungi in the marine ecosystem. Mangroves are ecosystems situated between land and sea. They are frequently found in tropical and subtropical areas and enclose approximately 18.1 million hectares of the planet. The great biodiversity found in these ecosystems shows the importance of researching them, including studies regarding new compounds derived from the endophytic fungi that inhabit these ecosystems. 3-hydroxypropionic acid (3-HPA) has been isolated from the mangrove endophytic fungus Diaporthe phaseolorum, which was obtained from branches of Laguncularia racemosa. The structure of this compound was elucidated by spectroscopic methods, mainly 1D and 2D NMR. In bioassays, 3-HPA showed antimicrobial activities against both Staphylococcus aureus and Salmonella typhi. The structure of this antibiotic was modified by the chemical reaction of Fischer-Speier esterification to evaluate the biologic activity of its chemical analog. The esterified product, 3-hydroxypropanoic ethyl ester, did not exhibit antibiotic activity, suggesting that the free carboxylic acid group is important to the pharmacological activity. The antibiotic-producing strain was identified with internal transcribed spacer sequence data. To the best of our knowledge, this is the first report of antibacterial activity by 3-HPA against the growth of medically important pathogens. 相似文献
995.
Caceres RA Timmers LF Ducati RG da Silva DO Basso LA de Azevedo WF Santos DS 《Biochimie》2012,94(1):155-165
Consumption has been a scourge of mankind since ancient times. This illness has charged a high price to human lives. Many efforts have been made to defeat Mycobacterium tuberculosis (Mt). The M. tuberculosis purine nucleoside phosphorylase (MtPNP) is considered an interesting target to pursuit new potential inhibitors, inasmuch it belongs to the purine salvage pathway and its activity might be involved in the mycobacterial latency process. Here we present the MtPNP crystallographic structure associated with acyclovir and phosphate (MtPNP:ACY:PO4) at 2.10 Å resolution. Molecular dynamics simulations were carried out in order to dissect MtPNP:ACY:PO4 structural features, and the influence of the ligand in the binding pocket stability. Our results revealed that the ligand leads to active site lost of stability, in agreement with experimental results, which demonstrate a considerable inhibitory activity against MtPNP (Ki = 150 nM). Furthermore, we observed that some residues which are important in the proper ligand’s anchor into the human homologous enzyme do not present the same importance to MtPNP. Therewithal, these findings contribute to the search of new specific inhibitors for MtPNP, since peculiarities between the mycobacterial and human enzyme binding sites have been identified, making a structural-based drug design feasible. 相似文献
996.
Izaura M. V. Cayres-Vallinoto Antonio C. R. Vallinoto Vania N. Azevedo Luis Fernando Almeida Machado Marluísa de Oliveira Guimar?es Ishak Ricardo Ishak 《PloS one》2012,7(10)
JC polyomavirus (JCV) is a member of the Polyomaviridae family. It presents a tropism to kidney cells, and the infection occurs in a variety of human population groups of different ethnic background. The present study investigated the prevalence of JCV infection among human populations from the Brazilian Amazon region, and describes the molecular and phylogenetic features of the virus. Urine samples from two urban groups of Belém (healthy subjects), one Brazilian Afro-descendant “quilombo” from the Rio Trombetas region, and native Indians from the Wai-Wai, Urubu-Kaapor, Tembé, Assurini, Arara do Laranjal, Aukre, Parakanã, Surui and Munduruku villages were investigated for the presence of the virus by amplifying VP1 (230 bp) and IG (610 bp) regions using a polymerase chain reaction. Nucleotide sequences (440 nucleotides, nt) from 48 samples were submitted to phylogenetic analysis. The results confirmed the occurrence of types A (subtype EU), B (subtypes Af-2, African and MY, Asiatic) and C (subtype Af-1) among healthy subjects; type B, subtypes Af-2 and MY, among the Afro-Brazilians; and type B, subtype MY, within the Surui Indians. An unexpected result was the detection of another polyomavirus, the BKV, among Afro-descendants. The present study shows, for the first time, the occurrence of JC and BK polyomaviruses infecting humans from the Brazilian Amazon region. The results show a large genetic variability of strains circulating in the region, infecting a large group of individuals. The presence of European, Asiatic and African subtypes associated to the ethnic origin of the population samples investigated herein, highlights the idea that JCV is a fairly good marker for studying the early migration of human populations, reflecting their early and late history. Furthermore, the identification of the specific mutations associated to the virus subtypes, suggests that these mutations have occurred after the entrance of the virus in the Amazon region of Brazil. 相似文献
997.
998.
Three new species of Dahlstedtia, D. burkartii, D. dehiscens, and D. lewisiana, are described from South America, and their relationships with related species are discussed. Dahlstedtia burkartii, from Argentina, has pink flowers with standard straight, whereas D. dehiscens and D. lewisiana, both from Brazil, have purplish to lilac flowers with a reflexed standard petal. A new combination, Dahlstedtia peckoltii, is proposed based on Lonchocarpus peckoltii and a neotype is selected for the latter. Information about geographic distribution and phenology of the species is provided. 相似文献
999.
Azevedo JS Ramos I Araújo S Oliveira CS Correia A Henriques IS 《Antonie van Leeuwenhoek》2012,101(4):819-835
Bacterioneuston may play a key role in water–air exchange of gases and in processing organic matter and pollutants that accumulate
at the sea-surface microlayer (SML). However, the phylogenetic diversity of bacterioneuston has been poorly characterized.
We analyzed 24 samples each from the SML and underlying water (UW) at three sites in the Ria de Aveiro estuary, Portugal. Cultivation and culture-independent techniques were used to compare bacterioneuston and bacterioplankton.
Culturable heterotrophic bacteria were enriched in the SML. The culturable community was dominated by Psychrobacter and Acinetobacter. The presence of high numbers of Psychrobacter was a notable result. Differences were confined to a few genera overrepresented in UW samples (Kocuria, Agrococcus and Vibrio). 16S rDNA DGGE profiles were highly stable in terms of number and position of bands between sampling sites and dates but
cluster analysis revealed a slight tendency for grouping according to sampled layer. SML-specific DGGE bands affiliated with
Actinobacteria, Cyanobacteria, Gammaproteobacteria and Bacteroidetes. Low similarity between nucleotide sequences of DGGE-bands and previously reported sequences suggest the occurrence of SML-specific
populations. Enrichment of SML for Pseudomonas and Aeromonas was questioned and the diversity of both communities was analyzed. Consistent differences between SML and UW aeromonads communities
were not identified. In terms of Pseudomonas, a culturable operational taxonomic unit was consistently overrepresented within SML samples. Taken together, our results
indicate that the similarity between SML and UW communities depends on spatial and temporal factors. 相似文献
1000.
Metabotrophic glutamate receptors (mGluRs) modulate cellular activities involved in the processes of differentiation and degeneration.
In this study, we have analysed the expression pattern of group-I metabotropic glutamate receptor (mGlu-5) in cerebral cortex,
corpus striatum, brainstem and hippocampus of streptozotocin induced and insulin treated diabetic rats (D+I) as a function
of age. Also, the functional role of glutamate receptors in intra cellular calcium release from the pancreatic islets was
studied in vitro. The gene expression studies showed that mGlu-5 mRNA in the cerebral cortex increased siginficantly in 7 weeks old diabetic
rats whereas decreased expression was observed in brainstem, corpus striatum and hippocampus when compared to control. 90
weeks old diabetic rats showed decreased expression in cerebral cortex, corpus striatum and hippocampus whereas in brainstem
the expression increased significantly compared to their respective controls. In 7 weeks old D+I group, mGlu-5 mRNA expression
was significantly decreased in cerebral cortex and corpus striatum whereas the expression increased significantly in brainstem
and hippocampus. 90 weeks old D+I group showed an increased expression in cerebral cortex, while it was decreased significantly
in corpus striatum, brainstem and hippocampus compared to their respective controls. In vitro studies showed that glutamate at lower concentration (10-7 M) stimulated calcium release from the pancreatic islets. Our results suggest that mGlu-5 receptors have differential expression
in brain regions of diabetes and D+I groups as a function of age. This will have clinical significance in management of degeneration
in brain function and memory enhancement through glutamate receptors. Also, the regulatory role of glutamate receptors in
calcium release has immense therapeutic application in insulin secretion and function. 相似文献