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51.
An occupied nest of Epipona media Cooper was discovered and collected in a cabruca (cocoa plantation with native tree cover). This is the first record of E. media from Bahia State. We described the nest structure and compared the adults with the closely related species Epipona tatua Cuvier. 相似文献
52.
Andressa S. Freitas Anna L.R. Xavier Carla M. Furtado Cecilia Hedin‐Pereira Maira M. Fróes João R.L. Menezes 《Developmental neurobiology》2012,72(12):1482-1497
In this study, we have analyzed the specific contribution of the cortical radial glia (RG) for gap junctional communication (GJC) within the postnatal subventricular zone (SVZ). To specifically target RG as source of dye‐coupling in situ, we have developed a new technique that involves direct cell loading through the processes that reach the pial surface, with a mix of gap junction permeant (Lucifer yellow, LY) and nonpermeant (rhodamine‐conjugated dextran 3 KDa, RD) fluorochromes, the latter used as a marker for direct loaded cells. Tissue sections were analyzed for identification of directly loaded (LY+RD+) and coupled cells (LY+RD–) in the SVZ. Directly loaded cells were restricted to the region underlying the pial loading surface area. Coupled cells were distributed in a bistratified manner, along the outer dorsal surface of the SVZ and aligning the ventricle, leaving the SVZ core relatively free. Blocking GJC prior to pial loading greatly reduced dye coupling. Phenotypic analysis indicated that coupling by RG excludes neuroblasts and is mostly restricted to cells of glial lineage. Notwithstanding, no corresponding restriction to specific cell phenotype was found for two connexin isotypes, Cx43 and Cx45, in the postnatal SVZ. The extensive homocellular cell coupling by RG suggests an important role in the regulation of neurogenesis and functional compartmentalization of the postnatal SVZ. © 2012 Wiley Periodicals, Inc. Develop Neurobiol 2012 相似文献
53.
Caroline Tanski Bueno Cláudia Maria Dornelles da Silva Regina Bones Barcellos Juliana da Silva Carla Rossana dos Santos Jo?o Evangelista Sampaio Menezes Honório Sampaio Menezes Maria Lucia Rosa Rossetti 《Genetics and molecular biology》2014,37(3):496-499
The aim of this study was to evaluate the association between the frequency of micronuclei (MN) and the cellular changes detected in the conventional Papanicolaou test. One hundred and seventy-four Papanicolaou test smears with cellular changes were examined. MN screening was done in cytopathological smears by counting 1,000 cervical cells in a light microscope. MN frequencies were significantly higher in the group with cellular changes compared to the control group (p < 0.001). The mean MN frequencies were 0.95 ± 1.12 (mean ± SD) in the control group (n = 223), 2.98 ± 1.20 in individuals with atypical squamous cells of undetermined significance (ASC-US) (n = 50), 4.04 ± 1.45 in cervical intraepithelial neoplasia (CIN) I (n = 52), 5.97 ± 1.83 in CIN II (n = 30), 7.29 ± 1.55 in CIN III (n = 17) and 8.64 ± 1.55 in invasive cancer (n = 25). These findings suggest that MN monitoring should be included as an additional criterion for the early detection of cytogenetic damage in routine examinations. This monitoring should be done in the same smear as used for cytopathological examination. More specific and systematic studies are necessary to confirm this proposal. 相似文献
54.
55.
Rosemberg Fernandes Menezes Finn Borchsenius Jens-Christian Svenning Martin Søndergaard Torben L. Lauridsen Frank Landkildehus Erik Jeppesen 《Hydrobiologia》2013,700(1):47-59
Organisms inhabiting shallow near-shore waters are at risk of desiccation during water level fluctuations. Using laboratory experiments, we investigated the survival and behavioural defences of four freshwater amphipod species during substratum drying: three Ponto-Caspian invaders (Pontogammarus robustoides, Dikerogammarus haemobaphes and Dikerogammarus villosus) and the native Gammarus fossarum. We hypothesized that they would be able to survive air exposure events as well as to adjust their behaviour by following the decreasing water level and/or burying in the sediments. To test these hypotheses, we examined survival of each species on gradually drying sandy substratum as well as their horizontal and vertical migration behaviours. P. robustoides was most resistant to substratum drying and was the only species burying into the substratum. On the other hand, G. fossarum exhibited distinct horizontal migrations following the retreating waterline. These two species seem to be particularly well adapted to the drying environment. Defence mechanisms of D. haemobaphes and D. villosus were less efficient, though the former species also followed the retreating waterline to some extent. Our study demonstrates that exotic and native gammarids have several adaptations that enable them to invade and persist in habitats experiencing common water level fluctuations. 相似文献
56.
Charlene Cavalheiro de Menezes Aracélli Gnatta Dorneles Rita Leal Sperotto Marta Medeiros Frescura Duarte Maria Rosa Chitolina Schetinger Vania Lúcia Loro 《Neurochemical research》2009,34(7):1255-1260
This study aimed to determine whether patients with aseptic and bacterial meningitis presented alterations in oxidative stress
parameters of cerebrospinal fluid (CSF). A total of 30 patients were used in the research. The CSF oxidative stress status
has been evaluated through many parameters, such as lipid peroxidation through thiobarbituric acid reactive substances (TBARS)
and antioxidant defense systems such as superoxide dismutase (SOD), glutathione S-transferase (GST), reduced glutathione (GSH) and ascorbic acid. TBARS levels, SOD and GST activity increase in aseptic meningitis
and in bacterial meningitis. The ascorbic acid concentration increased significantly in patients with both meningitis types.
The reduced glutathione levels were reduced in CSF of patients with aseptic and bacterial meningitis. In present study we
may conclude that oxidative stress contributes at least in part to the severe neurological dysfunction found in meningitis. 相似文献
57.
Marcelo R. de Carvalho Flávio A. Bockmann Dalton S. Amorim Carlos Roberto F. Brandão Mário de Vivo José L. de Figueiredo Heraldo A. Britski Mário C. C. de Pinna Naércio A. Menezes Fernando P. L. Marques Nelson Papavero Eliana M. Cancello Jorge V. Crisci John D. McEachran Robert C. Schelly John G. Lundberg Anthony C. Gill Ralf Britz Quentin D. Wheeler Melanie L. J. Stiassny Lynne R. Parenti Larry M. Page Ward C. Wheeler Julián Faivovich Richard P. Vari Lance Grande Chris J. Humphries Rob DeSalle Malte C. Ebach Gareth J. Nelson 《Evolutionary biology》2007,34(3-4):140-143
58.
Martins-de-Souza D Martins D Astua-Monge G Coletta-Filho HD Winck FV Baldasso PA de Oliveira BM Marangoni S Machado MA Novello JC Smolka MB 《Current microbiology》2007,54(2):119-123
The fastidious bacterium Xylella fastidiosa is associated with important crop diseases worldwide. We have recently shown that X. fastidiosa is a peculiar organism having unusually low values of gene codon bias throughout its genome and, unexpectedly, in the group of the most abundant proteins. Here, we hypothesized that the lack of codon usage optimization in X. fastidiosa would incapacitate this organism to undergo quick and massive changes in protein expression as occurs in a classical stress response. Proteomic analysis of the response to heat stress in X. fastidiosa revealed that no changes in protein expression can be detected. Moreover, stress-inducible proteins identified in the closely related citrus pathogen Xanthomonas axonopodis pv citri were found to be constitutively expressed in X. fastidiosa. These proteins have extremely high codon bias values in the X. citri and other well-studied organisms, but low values in X. fastidiosa. Because biased codon usage is well known to correlate to the rate of protein synthesis, we speculate that the peculiar codon bias distribution in X. fastidiosa is related to the absence of a classical stress response, and, probably, alternative strategies for survival of X. fastidiosa under stressfull conditions. 相似文献
59.
Daniel Martins Bruno Menezes de Oliveira Alessandro dos Santos Farias Ricardo Shiniti Oka Horiuchi Cleyton Crepaldi Domingues Eneida de Paula Sérgio Marangoni Wagner Farid Gattaz Emmanuel Dias-Neto José Camillo Novello 《Briefings in Functional Genomics and Prot》2007,6(1):70-75
Protein extraction is the most important step to reveal a proteome by Two-Dimensional Gel Electrophoresis. Usually, the urea/thiourea based standard protein extraction buffer (SB) is combined with detergents with the aim of achieving better resolution and solubilization of different classes of proteins. In order to produce better gels and achieve the greatest spot resolution of Human Brain Proteins, comparisons using 2-DE of extracted proteins from Human Brain Frontal Cortex with SB constituents (7M Urea, 2M Thiourea and 100mM DTT) were made, using different detergent compositions in the buffer. SB preparations in combination with CHAPS and ASB-14 as well as with ASB-16 (reported for the first time in 2-DE experiments) have been tested. Our results confirm that the most efficient solubilizing solution for 2-DE analysis of cytosolic and membrane Human Brain Proteins is SB combined with 4% CHAPS and 2% ASB-14. 相似文献
60.
Reinaldo de Menezes Martins Cristina de Albuquerque Possas Akira Homma 《Memórias do Instituto Oswaldo Cruz》2015,110(1):114-124
This paper presents, from the perspective of technological development and
production, the results of an investigation examining 61 clinical studies with
vaccines conducted in Brazil between 1938-2013, with the participation of the Oswaldo
Cruz Institute (IOC) and the Oswaldo Cruz Foundation (Fiocruz). These studies have
been identified and reviewed according to criteria, such as the kind of vaccine
(viral, bacterial, parasitic), their rationale, design and methodological strategies.
The results indicate that IOC and Fiocruz have accumulated along this time
significant knowledge and experience for the performance of studies in all clinical
phases and are prepared for the development of new vaccines products and processes.
We recommend national policy strategies to overcome existing regulatory and financing
constraints. 相似文献