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111.
Ribeiro RA Santos-Silva JC Vettorazzi JF Cotrim BB Mobiolli DD Boschero AC Carneiro EM 《Amino acids》2012,43(4):1791-1801
Taurine (Tau) is involved in beta (β)-cell function and insulin action regulation. Here, we verified the possible preventive effect of Tau in high-fat diet (HFD)-induced obesity and glucose intolerance and in the disruption of pancreatic β-cell morpho-physiology. Weaning Swiss mice were distributed into four groups: mice fed on HFD diet (36 % of saturated fat, HFD group); HTAU, mice fed on HFD diet and supplemented with 5 % Tau; control (CTL); and CTAU. After 19 weeks of diet and Tau treatments, glucose tolerance, insulin sensitivity and islet morpho-physiology were evaluated. HFD mice presented higher body weight and fat depots, and were hyperglycemic, hyperinsulinemic, glucose intolerant and insulin resistant. Their pancreatic islets secreted high levels of insulin in the presence of increasing glucose concentrations and 30 mM K+. Tau supplementation improved glucose tolerance and insulin sensitivity with a higher ratio of Akt phosphorylated (pAkt) related to Akt total protein content (pAkt/Akt) following insulin administration in the liver without altering body weight and fat deposition in HTAU mice. Isolated islets from HTAU mice released insulin similarly to CTL islets. HFD intake induced islet hypertrophy, increased β-cell/islet area and islet and β-cell mass content in the pancreas. Tau prevented islet and β-cell/islet area, and islet and β-cell mass alterations induced by HFD. The total insulin content in HFD islets was higher than that of CTL islets, and was not altered in HTAU islets. In conclusion, for the first time, we showed that Tau enhances liver Akt activation and prevents β-cell compensatory morpho-functional adaptations induced by HFD. 相似文献
112.
JS Gonçalves LM Ferracin ML Carneiro Vieira BT Iamanaka MH Taniwaki MH Pelegrinelli Fungaro 《World journal of microbiology & biotechnology》2012,28(4):1817-1825
Brazil nuts are an important export market in its main producing countries, including Brazil, Bolivia, and Peru. Approximately
30,000 tons of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs with subsequent production of aflatoxins. In our study, Aspergillus section Flavi were isolated from Brazil nuts (Bertholletia excelsa), and identified by morphological and molecular means. We obtained 241 isolates from nut samples, 41% positive for aflatoxin
production. Eighty-one isolates were selected for molecular investigation. Pairwise genetic distances among isolates and phylogenetic
relationships were assessed. The following Aspergillus species were identified: A. flavus, A. caelatus, A. nomius, A. tamarii,
A. bombycis, and A. arachidicola. Additionally, molecular profiles indicated a high level of nucleotide variation within β-tubulin and calmodulin gene sequences
associated with high genetic divergence from RAPD data. Among the 81 isolates analyzed by molecular means, three of them were
phylogenetically distinct from all other isolates representing the six species of section Flavi. A putative novel species was identified based on molecular profiles. 相似文献
113.
The genome from Neurospora crassa presented three open reading frames homologous to the genes coding for human AIF and AMID proteins, which are flavoproteins with oxidoreductase activities implicated in caspase-independent apoptosis. To investigate the role of these proteins, namely within the mitochondrial respiratory chain, we studied their cellular localization and characterized the respective null mutant strains. Efficiency of the respiratory chain was analyzed by oxygen consumption studies and supramolecular organization of the OXPHOS system was assessed through BN-PAGE analysis in the respective null mutant strains. The results demonstrate that, unlike in mammalian systems, disruption of AIF in Neurospora does not affect either complex I assembly or function. Furthermore, the mitochondrial respiratory chain complexes of the mutant strains display a similar supramolecular organization to that observed in the wild type strain. Further characterization revealed that N. crassa AIF appears localized to both the mitochondria and the cytoplasm, whereas AMID was found exclusively in the cytoplasm. AMID2 was detected in both mitochondria and cytoplasm of the amid mutant strain, but was barely discernible in wild type extracts, suggesting overlapping functions for the two proteins. 相似文献
114.
Rodrigues Queiróz AJ Nazareno LS Miranda JE de Azevedo AE Teixeira da Cruz CA Pirani Carneiro F Florêncio da Costa AC Lofrano-Porto A 《Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology》2012,28(8):633-636
Insulinomas are rare pancreatic β-cell tumors with an estimated incidence of 1:250.000 persons/year. We present a novel case of insulinoma manifesting immediately after childbirth. Eight days after delivery, a 21-year-old, previously healthy woman presented paresthesia in hands, upper and lower limbs muscle weakness with difficult walking, which worsened during breastfeeding sessions. Laboratory tests showed blood glucose levels between 37 and 55 mg/dL with inappropriately normal insulin levels (7.78 μUI/mL; normal range: 5-29). An abdominal computed tomography showed a nodular lesion measuring 2 cm at the head of the pancreas. Tumor enucleation resulted in complete resolution of hypoglycemia. Histopathological and immunohistochemical analysis were consistent with an insulinoma. About 27 cases of insulinoma associated with pregnancy have been reported to date, mostly diagnosed before the 16th week. The beginning of symptoms soon after delivery is less common. Understanding the interactions between pancreatic β-cell function and all the physiological metabolic and hormonal adaptations associated with gestation is essential for the adequate management of hypoglycemic disorders in pregnant women. 相似文献
115.
Manoela Kowalczuck E. Carneiro M. M. Casagrande O. H. H. Mielke 《Neotropical Entomology》2012,41(5):345-354
Despite the long history of forestry activity in Brazil and its importance to the national economy, there is still much disorder in the information regarding pests of forestry species. Considering the importance of the entomological knowledge for the viability of silvicultural management, this work aimed to gather information on the species of Lepidoptera associated with forestry crops within Brazil using a historical approach. Through a literature review, all registered species of Lepidoptera related to forestry crops in Brazil from 1896 to 2010 were identified. The historical evaluation was based on the comparison of the number of published articles, species richness, and community similarities of the Lepidoptera and their associated forest crops, grouped in 10-year samples. A total of 417 occurrences of Lepidoptera associated with forestry species were recorded, from which 84 species are related with 40 different forestry crops. The nocturnal Lepidoptera were dominant on the records, with Eacles imperialis magnifica Walker as the most frequent pest species cited. Myrtaceae was the most frequent plant family, with Cedrela fissilis as the most cited forestry crop species. A successional change in both Lepidoptera species and their host plants was observed over the decades. The richness of lepidopteran pest species increased over the years, unlike the richness of forestry crop species. This increase could be related to the inefficient enforcement of sanitary barriers, to the increase of monoculture areas, and to the adaptability of native pests to exotic forestry species used in monoculture stands. 相似文献
116.
Letícia Helena dos Santos Marques Luciana Inácia Gomes Iara Caixeta Marques da Rocha Thaís Almeida Marques da Silva Edward Oliveira Maria Helena Franco Morais Ana Rabello Mariangela Carneiro 《PLoS neglected tropical diseases》2012,6(12)
Background
An important issue associated with the control of visceral leishmaniasis is the need to identify and understand the relevance of asymptomatic infection caused by Leishmania infantum. The aim of this study was to follow the course of asymptomatic L. infantum infection in children in an area of Brazil where it is endemic. The children were assessed twice during a 12-month period.Methodology
In this population study, 1875 children, ranging from 6 months to 7 years of age, were assessed. Blood samples were collected on filter papers via finger prick and tested by ELISA (L. infantum soluble antigen and rk39). Seropositives samples (n = 317) and a number of seronegatives samples (n = 242) were subjected to qPCR. After 12 months, blood samples were collected from a subgroup of 199 children and tested for Leishmania spp. to follow the course of infection.Principal Findings
At baseline qPCR testing identified 82 positive samples. The prevalence rate, as estimated for 1875 children based on the qPCR results, was 13.9%. The qPCR testing of whole blood samples collected from a cohort of children after 12 months (n = 199) yielded the following results: of the 44 (22.1%) children with positive qPCR results at baseline, only 10 (5.0%) remained positive, and 34 (17.1%) became negative; and of the 155 (77.9%) children with negative qPCR results, 131 (65.8%) remained negative, and 24 (12.1%) became positive at the follow-up measurement. The samples with positive findings at baseline (n = 82) had a mean of 56.5 parasites/mL of blood; and at follow-up the mean positive result was 7.8 parasites/mL.Conclusions
The peripheral blood of asymptomatic children had a low and fluctuating quantity of Leishmania DNA and a significant decrease in parasitemia at 1-year follow-up. Quantitative PCR enables adequate monitoring of Leishmania infection. 相似文献117.
Zimberg IZ Dâmaso A Del Re M Carneiro AM de Sá Souza H de Lira FS Tufik S de Mello MT 《Cell biochemistry and function》2012,30(6):524-529
A reduction of sleep time has become common over the last century, and growing evidence from both epidemiological and laboratory-based studies suggests sleep curtailment is a new risk factor for the development of obesity. On this basis, the present review examines the role of sleep curtailment in the metabolic and endocrine alterations, including decreased glucose tolerance and insulin sensitivity, increased evening concentrations of cortisol, increased levels of ghrelin, decreased levels of leptin and increased hunger and appetite. It will be discussed how sleep restriction may lead to increase in food intake and result in greater fatigue, which may favour decreased energy expenditure. Altogether, evidences point to a possible role of decreased sleep duration in the current epidemic of obesity and therefore present literature highlights the importance of getting enough good sleep for metabolic health. Many aspects still need to be clarified and intervention studies also need to be conducted. Copyright ? 2012 John Wiley & Sons, Ltd. 相似文献
118.
Frank W. Albert Mehmet Somel Miguel Carneiro Ayinuer Aximu-Petri Michel Halbwax Olaf Thalmann Jose A. Blanco-Aguiar Irina Z. Plyusnina Lyudmila Trut Rafael Villafuerte Nuno Ferrand Sylvia Kaiser Per Jensen Svante P??bo 《PLoS genetics》2012,8(9)
Domestication has led to similar changes in morphology and behavior in several animal species, raising the question whether similarities between different domestication events also exist at the molecular level. We used mRNA sequencing to analyze genome-wide gene expression patterns in brain frontal cortex in three pairs of domesticated and wild species (dogs and wolves, pigs and wild boars, and domesticated and wild rabbits). We compared the expression differences with those between domesticated guinea pigs and a distant wild relative (Cavia aperea) as well as between two lines of rats selected for tameness or aggression towards humans. There were few gene expression differences between domesticated and wild dogs, pigs, and rabbits (30–75 genes (less than 1%) of expressed genes were differentially expressed), while guinea pigs and C. aperea differed more strongly. Almost no overlap was found between the genes with differential expression in the different domestication events. In addition, joint analyses of all domesticated and wild samples provided only suggestive evidence for the existence of a small group of genes that changed their expression in a similar fashion in different domesticated species. The most extreme of these shared expression changes include up-regulation in domesticates of SOX6 and PROM1, two modulators of brain development. There was almost no overlap between gene expression in domesticated animals and the tame and aggressive rats. However, two of the genes with the strongest expression differences between the rats (DLL3 and DHDH) were located in a genomic region associated with tameness and aggression, suggesting a role in influencing tameness. In summary, the majority of brain gene expression changes in domesticated animals are specific to the given domestication event, suggesting that the causative variants of behavioral domestication traits may likewise be different. 相似文献
119.
Rommel Thiago Jucá Ramos Adriana Ribeiro Carneiro Vasco Azevedo Maria Paula Schneider Debmalya Barh Artur Silva 《Bioinformation》2012,8(20):996-999
Modern genomic sequencing technologies produce a large amount of data with reduced cost per base; however, this data consists
of short reads. This reduction in the size of the reads, compared to those obtained with previous methodologies, presents new
challenges, including a need for efficient algorithms for the assembly of genomes from short reads and for resolving repetitions.
Additionally after abinitio assembly, curation of the hundreds or thousands of contigs generated by assemblers demands
considerable time and computational resources. We developed Simplifier, a stand-alone software that selectively eliminates
redundant sequences from the collection of contigs generated by ab initio assembly of genomes. Application of Simplifier to data
generated by assembly of the genome of Corynebacterium pseudotuberculosis strain 258 reduced the number of contigs generated by
ab initio methods from 8,004 to 5,272, a reduction of 34.14%; in addition, N50 increased from 1 kb to 1.5 kb. Processing the contigs of
Escherichia coli DH10B with Simplifier reduced the mate-paired library 17.47% and the fragment library 23.91%. Simplifier removed
redundant sequences from datasets produced by assemblers, thereby reducing the effort required for finalization of genome
assembly in tests with data from Prokaryotic organisms.
Availability
Simplifier is available at http://www.genoma.ufpa.br/rramos/softwares/simplifier.xhtmlIt requires Sun jdk 6 or higher. 相似文献120.
Microsatellite mutations in the offspring of irradiated parents 19 years after the Cesium-137 accident 总被引:1,自引:0,他引:1
da Cruz AD de Melo e Silva D da Silva CC Nelson RJ Ribeiro LM Pedrosa ER Jayme JC Curado MP 《Mutation research》2008,652(2):175-179
In September of 1987, a radiotherapy unit containing 50.9 TBq of Cs(137)Cl was removed from an abandoned radiotherapy clinic. This unit was subsequently disassembled leading to the most serious radiological accident yet to occur in the Western hemisphere. This event provides an opportunity to assess the genetic effects of ionizing radiation. We surveyed genetic variation of 12 microsatellite loci in 10 families of exposed individuals and their offspring and also in non-exposed families from the same area of Goias state. We found an increase in the number of new alleles in the offspring of the exposed individuals. The mutation rate was found to be higher in the exposed families compared to the control group. These results indicated that exposure to ionizing radiation can be detected in offspring of exposed individuals and also suggest that the elevated microsatellite mutation rate can be attributed to radioactive exposure. 相似文献