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121.
Alterations in antioxidant defense in obese people with metabolic syndrome can contribute to oxidative stress. This study assessed the relationship between the parameters of metabolic syndrome and the zincemia, activity of superoxide dismutase, and glutathione peroxidase enzymes in obese women. Seventy-three premenopausal women, aged between 20 and 50 years, were divided into two groups: case group, composed of obese (n = 37), and control group, composed of no obese (n = 36). Analyses of zinc intake, parameters of metabolic syndrome, plasma, and erythrocyte zinc, and activities of superoxide dismutase and glutathione peroxidase were carried out. The mean values of body mass index of obese women and control group were 34.5 ± 3.4 and 21.7 ± 1.9 kg/m2, respectively (p < 0.05). In the study, body mass index, waist circumference, and zinc intake were higher in obese women than control group (p < 0.05). The plasma zinc and activity of superoxide dismutase did not show significant differences between obese and controls (p > 0.05). The values of erythrocyte zinc was 36.4 ± 15.0 μg/gHb and 45.4 ± 14.3 μg/gHb and of glutathione peroxidase was 46.4 ± 19.4 U/gHb and 36.7 ± 13.6 U/gHb in obese women and controls, respectively (p < 0.05). The study shows that there are alterations in biochemical parameters of zinc in obese women, with low zinc concentrations in erythrocytes. Regression analysis demonstrates that the erythrocyte zinc and activity of superoxide dismutase enzyme is influenced by components of the metabolic syndrome, and the plasmatic glucose, body mass index, and waist circumference have a negative correlation with this enzyme.  相似文献   
122.
The synthesis of six 3-aryl-5-(n-propyl)-4,5dihydro-1,2,4-oxadiazoles 3a-f has been achieved in a facile manner by the reaction of an appropriate arylamidoxime 1a-f with butyraldehyde 2. Oxidation of 3a-f individually using MnO(2) in CH(2)Cl(2) or sodium hypochlorite in THF/H(2)O furnished 1,2,4-oxadiazoles 4a-f in good to excellent yields. Compounds 4a-f were also evaluated against inflammation. Except 4e, all of them reduced inflammation, however, 4c presented better antiinflammatory activity. A preliminary antimicrobial activity tests of 3a-f showed that these compounds possess activity against some microorganisms. In fact, 3c and 3f have been found to be more effective against Staphylococcus aureus, Mycobacterium smegmatis, and Candida albicans.  相似文献   
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Ronald C. Kessler  Sherri Rose  Karestan C. Koenen  Elie G. Karam  Paul E. Stang  Dan J. Stein  Steven G. Heeringa  Eric D. Hill  Israel Liberzon  Katie A. McLaughlin  Samuel A. McLean  Beth E. Pennell  Maria Petukhova  Anthony J. Rosellini  Ayelet M. Ruscio  Victoria Shahly  Arieh Y. Shalev  Derrick Silove  Alan M. Zaslavsky  Matthias C. Angermeyer  Evelyn J. Bromet  José Miguel Caldas de Almeida  Giovanni de Girolamo  Peter de Jonge  Koen Demyttenaere  Silvia E. Florescu  Oye Gureje  Josep Maria Haro  Hristo Hinkov  Norito Kawakami  Viviane Kovess‐Masfety  Sing Lee  Maria Elena Medina‐Mora  Samuel D. Murphy  Fernando Navarro‐Mateu  Marina Piazza  Jose Posada‐Villa  Kate Scott  Yolanda Torres  Maria Carmen Viana 《World psychiatry》2014,13(3):265-274
Post‐traumatic stress disorder (PTSD) should be one of the most preventable mental disorders, since many people exposed to traumatic experiences (TEs) could be targeted in first response settings in the immediate aftermath of exposure for preventive intervention. However, these interventions are costly and the proportion of TE‐exposed people who develop PTSD is small. To be cost‐effective, risk prediction rules are needed to target high‐risk people in the immediate aftermath of a TE. Although a number of studies have been carried out to examine prospective predictors of PTSD among people recently exposed to TEs, most were either small or focused on a narrow sample, making it unclear how well PTSD can be predicted in the total population of people exposed to TEs. The current report investigates this issue in a large sample based on the World Health Organization (WHO)'s World Mental Health Surveys. Retrospective reports were obtained on the predictors of PTSD associated with 47,466 TE exposures in representative community surveys carried out in 24 countries. Machine learning methods (random forests, penalized regression, super learner) were used to develop a model predicting PTSD from information about TE type, socio‐demographics, and prior histories of cumulative TE exposure and DSM‐IV disorders. DSM‐IV PTSD prevalence was 4.0% across the 47,466 TE exposures. 95.6% of these PTSD cases were associated with the 10.0% of exposures (i.e., 4,747) classified by machine learning algorithm as having highest predicted PTSD risk. The 47,466 exposures were divided into 20 ventiles (20 groups of equal size) ranked by predicted PTSD risk. PTSD occurred after 56.3% of the TEs in the highest‐risk ventile, 20.0% of the TEs in the second highest ventile, and 0.0‐1.3% of the TEs in the 18 remaining ventiles. These patterns of differential risk were quite stable across demographic‐geographic sub‐samples. These results demonstrate that a sensitive risk algorithm can be created using data collected in the immediate aftermath of TE exposure to target people at highest risk of PTSD. However, validation of the algorithm is needed in prospective samples, and additional work is warranted to refine the algorithm both in terms of determining a minimum required predictor set and developing a practical administration and scoring protocol that can be used in routine clinical practice.  相似文献   
126.
This is second part from an experiment where the nitrogen retention of poultry by-product meal (PBM) compared to fishmeal (FM) was evaluated using traditional indices. Here a quantitative method using stable isotope ratios of nitrogen (δ15N values) as natural tracers of nitrogen incorporation into fish biomass is assessed. Juvenile rainbow trout (Oncorhynchus mykiss) were fed for 80 days on isotopically distinct diets in which 0, 33, 66 and 100% of FM as main protein source was replaced by PBM. The diets were isonitrogenous, isolipidic and similar in gross energy content. Fish in all treatments reached isotopic equilibrium by the end of the experiment. Two-source isotope mixing models that incorporated the isotopic composition of FM and PBM as well as that of formulated feeds, empirically derived trophic discrimination factors and the isotopic composition of fish that had reached isotopic equilibrium to the diets were used to obtain a quantitative estimate of the retention of each source of nitrogen. Fish fed the diets with 33 and 66% replacement of FM by PBM retained poultry by-product meal roughly in proportion to its level of inclusion in the diets, whereas no differences were detected in the protein efficiency ratio. Coupled with the similar biomass gain of fishes fed the different diets, our results support the inclusion of PBM as replacement for fishmeal in aquaculture feeds. A re-feeding experiment in which all fish were fed a diet of 100% FM for 28 days indicated isotopic turnover occurred very fast, providing further support for the potential of isotopic ratios as tracers of the retention of specific protein sources into fish tissues. Stable isotope analysis is a useful tool for studies that seek to obtain quantitative estimates of the retention of different protein sources.  相似文献   
127.
The canga of the Serra dos Carajás, in Eastern Amazon, is home to a unique open plant community, harboring several endemic and rare species. Although a complete flora survey has been recently published, scarce to no genetic information is available for most plant species of the ironstone outcrops of the Serra dos Carajás. In this scenario, DNA barcoding appears as a fast and effective approach to assess the genetic diversity of the Serra dos Carajás flora, considering the growing need for robust biodiversity conservation planning in such an area with industrial mining activities. Thus, after testing eight different DNA barcode markers (matK, rbcL, rpoB, rpoC1, atpF‐atpH, psbK‐psbI, trnH‐psbA, and ITS2), we chose rbcL and ITS2 as the most suitable markers for a broad application in the regional flora. Here we describe DNA barcodes for 1,130 specimens of 538 species, 323 genera, and 115 families of vascular plants from a highly diverse flora in the Amazon basin, with a total of 344 species being barcoded for the first time. In addition, we assessed the potential of using DNA metabarcoding of bulk samples for surveying plant diversity in the canga. Upon achieving the first comprehensive DNA barcoding effort directed to a complete flora in the Brazilian Amazon, we discuss the relevance of our results to guide future conservation measures in the Serra dos Carajás.  相似文献   
128.
Visceral leishmaniasis (VL) is caused by protozoa belonging to the Leishmania donovani complex and is considered the most serious and fatal form among the different types of leishmaniasis, if not early diagnosed and treated. Among the measures of disease control stand out the management of infected dogs and the early diagnosis and appropriate treatment of human cases. Several antigens have been characterized for use in the VL diagnosis, among them are the recombinant kinesin-derived antigens from L. infantum, as rK39 and rKDDR. The main difference between these antigens is the size of the non-repetitive kinesin region and the number of repetitions of the 39 amino acid degenerate motif (6.5 and 8.5 repeats in rK39 and rKDDR, respectively). This repetitive region has a high antigenicity score. To evaluate the effect of increasing the number of repeats on diagnostic performance, we designed the rKDDR-plus antigen, containing 15.3 repeats of the 39 amino acid degenerate motif, besides the absence of the non-repetitive portion from L. infantum kinesin. Its performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and rapid immunochromatographic test (ICT), and compared with the kinesin-derived antigens (rKDDR and rK39). In ELISA with human sera, all recombinant antigens had a sensitivity of 98%, whereas the specificity for rKDDR-plus, rKDDR and rK39 was 100%, 96% and 71%, respectively. When evaluated canine sera, the ELISA sensitivity was 97% for all antigens, and the specificity for rKDDR-plus, rKDDR and rK39 was 98%, 91% and 83%, respectively. Evaluation of the ICT/rKDDR-plus, using human sera, showed greater diagnostic sensitivity (90%) and specificity (100%), when compared to the IT LEISH (79% and 98%, respectively), which is based on the rK39 antigen. These results suggest that the increased presence of repetitive motifs in the rKDDR-plus protein improves the diagnostic performance of serological tests by increasing the specificity and accuracy of the diagnosis.  相似文献   
129.
For decades there have been anecdotal claims of synergistic interactions between plant-parasitic nematodes and soil-borne fungi causing decline of productivity of passion fruit (Passiflora edulis) orchards. An empirical confirmation of these disease complexes would impact disease management and plant breeding for resistance. To test those claims, we subjected passion fruit plants to single or concomitant parasitism by Meloidogyne javanica or M. incognita and Fusarium nirenbergiae or Neocosmospora sp. under controlled conditions. Non-inoculated plants served as control for the assays. The severity of shoot symptoms and variables related to plant growth, the extent of fungal lesions, and nematode reproduction were assessed to characterize the interactions. The shoot symptoms and effect on plant growth induced by the pathogens varied, but no synergy between the pathogens was observed. Moreover, the volume of tissue lesioned by the fungi was not affected by co-parasitism of the nematodes. Conversely, plant resistance to the nematodes was not affected by co-parasitism of the fungi. The interactions M. incognita-F. nirenbergiae, M. incognita-Neocosmospora sp., M. javanica-F. nirenbergiae, and M. javanica-Neocosmospora sp. were not synergistic as previously claimed, but instead neutral.  相似文献   
130.
Different variants of hepatitis C virus core protein (HCcAg) have proved to self-assemble in vitro into virus-like particles (VLPs). However, difficulties in obtaining purified mature HCcAg have limited these studies. In this study, a high degree of monomeric HCcAg purification was accomplished using chromatographic procedures under denaturing conditions. Size exclusion chromatography and sucrose density gradient centrifugation of renatured HCcAg (in the absence of structured RNA) under reducing conditions suggested that it assembled into empty capsids. The electron microscopy analysis of renatured HCcAg showed the presence of spherical VLPs with irregular shapes and an average diameter of 35nm. Data indicated that HCcAg monomers assembled in vitro into VLPs in the absence of structured RNA, suggesting that recombinant HCcAg used in this work contains all the information necessary for the assembly process. However, they also suggest that some cellular factors might be required for the proper in vitro assembly of capsids.  相似文献   
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