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41.
42.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献43.
Molecular phylogeny and divergence times of drosophilid species 总被引:17,自引:15,他引:17
The phylogenetic relationships and divergence times of 39 drosophilid
species were studied by using the coding region of the Adh gene. Four
genera--Scaptodrosophila, Zaprionus, Drosophila, and Scaptomyza (from
Hawaii)--and three Drosophila subgenera--Drosophila, Engiscaptomyza, and
Sophophora--were included. After conducting statistical analyses of the
nucleotide sequences of the Adh, Adhr (Adh-related gene), and nuclear rRNA
genes and a 905-bp segment of mitochondrial DNA, we used Scaptodrosophila
as the outgroup. The phylogenetic tree obtained showed that the first major
division of drosophilid species occurs between subgenus Sophophora (genus
Drosophila) and the group including subgenera Drosophila and Engiscaptomyza
plus the genera Zaprionus and Scaptomyza. Subgenus Sophophora is then
divided into D. willistoni and the clade of D. obscura and D. melanogaster
species groups. In the other major drosophilid group, Zaprionus first
separates from the other species, and then D. immigrans leaves the
remaining group of species. This remaining group then splits into the D.
repleta group and the Hawaiian drosophilid cluster (Hawaiian Drosophila,
Engiscaptomyza, and Scaptomyza). Engiscaptomyza and Scaptomyza are tightly
clustered. Each of the D. repleta, D. obscura, and D. melanogaster groups
is monophyletic. The splitting of subgenera Drosophila and Sophophora
apparently occurred about 40 Mya, whereas the D. repleta group and the
Hawaiian drosophilid cluster separated about 32 Mya. By contrast, the
splitting of Engiscaptomyza and Scaptomyza occurred only about 11 Mya,
suggesting that Scaptomyza experienced a rapid morphological evolution. The
D. obscura and D. melanogaster groups apparently diverged about 25 Mya.
Many of the D. repleta group species studied here have two functional Adh
genes (Adh-1 and Adh-2), and these duplicated genes can be explained by two
duplication events.
相似文献
44.
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
45.
CA Kalva-Filho EZ Campos VL Andrade ASR Silva AM Zagatto MCS Lima M Papoti 《Biology of sport / Institute of Sport》2015,32(4):333-337
The aims of the present study were to investigate the relationship of aerobic and anaerobic parameters with 400 m performance, and establish which variable better explains long distance performance in swimming. Twenty-two swimmers (19.1±1.5 years, height 173.9±10.0 cm, body mass 71.2±10.2 kg; 76.6±5.3% of 400 m world record) underwent a lactate minimum test to determine lactate minimum speed (LMS) (i.e., aerobic capacity index). Moreover, the swimmers performed a 400 m maximal effort to determine mean speed (S400m), peak oxygen uptake () and total anaerobic contribution (CANA). The CANA was assumed as the sum of alactic and lactic contributions. Physiological parameters of 400 m were determined using the backward extrapolation technique ( and alactic contributions of CANA) and blood lactate concentration analysis (lactic anaerobic contributions of CANA). The Pearson correlation test and backward multiple regression analysis were used to verify the possible correlations between the physiological indices (predictor factors) and S400m (independent variable) (p < 0.05). Values are presented as mean ± standard deviation. Significant correlations were observed between S400m (1.4±0.1 m·s-1) and LMS (1.3±0.1 m·s-1; r = 0.80), (4.5±3.9 L·min-1; r = 0.72) and CANA (4.7±1.5 L·O2; r= 0.44). The best model constructed using multiple regression analysis demonstrated that LMS and explained 85% of the 400 m performance variance. When backward multiple regression analysis was performed, CANA lost significance. Thus, the results demonstrated that both aerobic parameters (capacity and power) can be used to predict 400 m swimming performance. 相似文献
46.
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
47.
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
48.
Luciana Gomes Menezes Cláudia Sobreira Luciano Neder Antonio Luis Rodrigues-Júnior José A Baddini Martinez 《Journal of applied physiology》2007,102(2):698-703
The objective of the present study was to investigate whether creatine (Cr) could attenuate the deleterious effects of high doses of dexamethasone (Dexa) on body mass, exercise performance, and respiratory variables of rodents. Forty-four Wistar rats performed incremental maximal exercise tests. They were then assigned to four groups: G1: subcutaneous (s.c.) and intraperitoneal (i.p.) saline; G2: s.c. saline and i.p. Cr (250 mg x kg(-1) x day(-1)); G3: s.c. Dexa (7.5 mg x kg(-1) x day(-1)) and i.p. saline; G4: s.c. Dexa and i.p. Cr. New exercise tests and analysis of the respiratory pattern under resting conditions and after stimulation with doxapram (2 mg/kg i.p.) were performed after 18 days. Post- minus pretreatment differences were compared between groups. G3 and G4 showed a significant impairment in body mass gain compared with G1 and G2 (P < 0.05) (G1: 65.3 +/- 26.1, G2: 93.1 +/- 27.4, G3: -18.4 +/- 20.1, G4: 9.8 +/- 23.1 kg x 10(-3)). Similar results were observed for maximal oxygen consumption (G1: 9.5 +/- 8.5, G2: 25.8 +/- 14.5, G3: -25.5 +/- 6.0, G4: -4.8 +/- 9.5 ml x kg(-1) x min(-1)) and test duration (G1: 43.0 +/- 45.0, G2: 72.0 +/- 59.5, G3: -165.0 +/- 60.6, G4: -48.0 +/- 48.5 s). Simultaneous use of Cr significantly attenuated the Dexa-induced impairment of the last two variables. Cr attenuated Dexa-induced gastrocnemius and diaphragm muscle weight losses and the atrophy of gastrocnemius type IIb fibers. Cr supplementation had only small effects on Dexa-induced respiratory changes. These results suggest that Cr may play a role in the prophylaxis or treatment of steroid-induced myopathy. 相似文献
49.
Gregory CA Amos Emma Gozzard Charlotte E Carter Andrew Mead Mike J Bowes Peter M Hawkey Lihong Zhang Andrew C Singer William H Gaze Elizabeth M H Wellington 《The ISME journal》2015,9(6):1467-1476
Multi-drug-resistant bacteria pose a significant threat to public health. The role of the environment in the overall rise in antibiotic-resistant infections and risk to humans is largely unknown. This study aimed to evaluate drivers of antibiotic-resistance levels across the River Thames catchment, model key biotic, spatial and chemical variables and produce predictive models for future risk assessment. Sediment samples from 13 sites across the River Thames basin were taken at four time points across 2011 and 2012. Samples were analysed for class 1 integron prevalence and enumeration of third-generation cephalosporin-resistant bacteria. Class 1 integron prevalence was validated as a molecular marker of antibiotic resistance; levels of resistance showed significant geospatial and temporal variation. The main explanatory variables of resistance levels at each sample site were the number, proximity, size and type of surrounding wastewater-treatment plants. Model 1 revealed treatment plants accounted for 49.5% of the variance in resistance levels. Other contributing factors were extent of different surrounding land cover types (for example, Neutral Grassland), temporal patterns and prior rainfall; when modelling all variables the resulting model (Model 2) could explain 82.9% of variations in resistance levels in the whole catchment. Chemical analyses correlated with key indicators of treatment plant effluent and a model (Model 3) was generated based on water quality parameters (contaminant and macro- and micro-nutrient levels). Model 2 was beta tested on independent sites and explained over 78% of the variation in integron prevalence showing a significant predictive ability. We believe all models in this study are highly useful tools for informing and prioritising mitigation strategies to reduce the environmental resistome. 相似文献
50.
Rodolpho Santos Telles Menezes Seán Gary Brady Ant?nio Freire Carvalho Marco Antonio Del Lama Marco Ant?nio Costa 《PloS one》2015,10(3)
The Neotropical Region harbors high biodiversity and many studies on mammals, reptiles, amphibians and avifauna have investigated the causes for this pattern. However, there is a paucity of such studies that focus on Neotropical insect groups. Synoeca de Saussure, 1852 is a Neotropical swarm-founding social wasp genus with five described species that is broadly and conspicuously distributed throughout the Neotropics. Here, we infer the phylogenetic relationships, diversification times, and historical biogeography of Synoeca species. We also investigate samples of the disjoint populations of S. septentrionalis that occur in both northwestern parts of South America through Central American and the Brazilian Atlantic rainforests. Our results showed that the interspecific relationships for Synoeca could be described as follows: (S. chalibea + S. virginea) + (S. cyanea + (S. septentrionalis/S. surinama)). Notably, samples of S. septentrionalis and S. surinama collected in the Atlantic Forest were interrelated and may be the result of incomplete lineage sorting and/or mitochondrial introgression among them. Our Bayesian divergence dating analysis revealed recent Plio-Pleistocene diversification in Synoeca. Moreover, our biogeographical analysis suggested an Amazonian origin of Synoeca, with three main dispersal events subsequently occurring during the Plio-Pleistocene. 相似文献