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211.
DR Feikin MK Njenga G Bigogo B Aura G Aol A Audi G Jagero PO Muluare S Gikunju L Nderitu A Balish J Winchell E Schneider D Erdman MS Oberste MA Katz RF Breiman 《PloS one》2012,7(8):e43656
BACKGROUND: Few comprehensive data exist on disease incidence for specific etiologies of acute respiratory illness (ARI) in older children and adults in Africa. METHODOLOGY/PRINCIPAL FINDINGS: From March 1, 2007, to February 28, 2010, among a surveillance population of 21,420 persons >5 years old in rural western Kenya, we collected blood for culture and malaria smears, nasopharyngeal and oropharyngeal swabs for quantitative real-time PCR for ten viruses and three atypical bacteria, and urine for pneumococcal antigen testing on outpatients and inpatients meeting a ARI case definition (cough or difficulty breathing or chest pain and temperature >38.0°C or oxygen saturation <90% or hospitalization). We also collected swabs from asymptomatic controls, from which we calculated pathogen-attributable fractions, adjusting for age, season, and HIV-status, in logistic regression. We calculated incidence by pathogen, adjusting for health-seeking for ARI and pathogen-attributable fractions. Among 3,406 ARI patients >5 years old (adjusted annual incidence 12.0 per 100 person-years), influenza A virus was the most common virus (22% overall; 11% inpatients, 27% outpatients) and Streptococcus pneumoniae was the most common bacteria (16% overall; 23% inpatients, 14% outpatients), yielding annual incidences of 2.6 and 1.7 episodes per 100 person-years, respectively. Influenza A virus, influenza B virus, respiratory syncytial virus (RSV) and human metapneumovirus were more prevalent in swabs among cases (22%, 6%, 8% and 5%, respectively) than controls. Adenovirus, parainfluenza viruses, rhinovirus/enterovirus, parechovirus, and Mycoplasma pneumoniae were not more prevalent among cases than controls. Pneumococcus and non-typhi Salmonella were more prevalent among HIV-infected adults, but prevalence of viruses was similar among HIV-infected and HIV-negative individuals. ARI incidence was highest during peak malaria season. CONCLUSIONS/SIGNFICANCE: Vaccination against influenza and pneumococcus (by potential herd immunity from childhood vaccination or of HIV-infected adults) might prevent much of the substantial ARI incidence among persons >5 years old in similar rural African settings. 相似文献
212.
Vinet Coetzee Stella J. Faerber Jaco M. Greeff Carmen E. Lefevre Daniel E. Re David I. Perrett 《PloS one》2012,7(10)
Little is known about mate choice preferences outside Western, educated, industrialised, rich and democratic societies, even though these Western populations may be particularly unrepresentative of human populations. To our knowledge, this is the first study to test which facial cues contribute to African perceptions of African female attractiveness and also the first study to test the combined role of facial adiposity, skin colour (lightness, yellowness and redness), skin homogeneity and youthfulness in the facial attractiveness preferences of any population. Results show that youthfulness, skin colour, skin homogeneity and facial adiposity significantly and independently predict attractiveness in female African faces. Younger, thinner women with a lighter, yellower skin colour and a more homogenous skin tone are considered more attractive. These findings provide a more global perspective on human mate choice and point to a universal role for these four facial cues in female facial attractiveness. 相似文献
213.
Robinson PW Costa DP Crocker DE Gallo-Reynoso JP Champagne CD Fowler MA Goetsch C Goetz KT Hassrick JL Hückstädt LA Kuhn CE Maresh JL Maxwell SM McDonald BI Peterson SH Simmons SE Teutschel NM Villegas-Amtmann S Yoda K 《PloS one》2012,7(5):e36728
The mesopelagic zone of the northeast Pacific Ocean is an important foraging habitat for many predators, yet few studies have addressed the factors driving basin-scale predator distributions or inter-annual variability in foraging and breeding success. Understanding these processes is critical to reveal how conditions at sea cascade to population-level effects. To begin addressing these challenging questions, we collected diving, tracking, foraging success, and natality data for 297 adult female northern elephant seal migrations from 2004 to 2010. During the longer post-molting migration, individual energy gain rates were significant predictors of pregnancy. At sea, seals focused their foraging effort along a narrow band corresponding to the boundary between the sub-arctic and sub-tropical gyres. In contrast to shallow-diving predators, elephant seals target the gyre-gyre boundary throughout the year rather than follow the southward winter migration of surface features, such as the Transition Zone Chlorophyll Front. We also assessed the impact of added transit costs by studying seals at a colony near the southern extent of the species' range, 1,150 km to the south. A much larger proportion of seals foraged locally, implying plasticity in foraging strategies and possibly prey type. While these findings are derived from a single species, the results may provide insight to the foraging patterns of many other meso-pelagic predators in the northeast Pacific Ocean. 相似文献
214.
In this study, the effects of cadmium (Cd) on cell morphology and antioxidant enzyme activities as well as the distribution
of the metal in different cell compartments in Bradyrhizobium sp. strains were investigated. These strains were previously classified as sensitive (Bradyrhizobium sp. SEMIA 6144) and tolerant (Bradyrhizobium sp. NLH25) to Cd. Transmission electron micrographs showed large electron-translucent inclusions in the sensitive strain
and electron-dense bodies in the tolerant strain, when exposed to Cd. Analysis of Cd distribution revealed that it was mainly
bounded to cell wall in both strains. Antioxidant enzyme activities were significantly different in each strain. Only the
tolerant strain was able to maintain a glutathione/oxidized glutathione (GSH/GSSG) ratio by an increase of GSH reductase (GR)
and GSH peroxidase (GPX) enzyme activities. GSH S-transferase (GST) and catalase (CAT) activities were drastically inhibited
in both strains while superoxide dismutase (SOD) showed a significant decrease only in the sensitive strain. In conclusion,
our findings suggest that GSH content and its related enzymes are involved in the Bradyrhizobium sp. tolerance to Cd contributing to the cellular redox balance. 相似文献
215.
Salmaso M Malacarne G Troggio M Faes G Stefanini M Grando MS Velasco R 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2008,116(8):1129-1143
Grapevine molecular maps based on microsatellites, AFLP and RAPD markers are now available. SSRs are essential to allow cross-talks
between maps, thus upgrading any growing grapevine maps. In this work, single nucleotide polymorphisms (SNPs) were developed
from coding sequences and from unique BAC-end sequences, and nested in a SSR framework map of grapevine. Genes participating
to flavonoids metabolism and defence, and signal transduction pathways related genes were also considered. Primer pairs for
351 loci were developed from ESTs present on public databases and screened for polymorphism in the “Merzling” (a complex genotype
Freiburg 993–60 derived from multiple crosses also involving wild Vitis species) × Vitis vinifera (cv. Teroldego) cross population. In total 138 SNPs, 108 SSR markers and a phenotypic trait (berry colour) were mapped in
19 major linkage groups of the consensus map. In specific cases, ESTs with putatively related functions mapped near QTLs previously
identified for resistance and berry ripening. Genes related to anthocyanin metabolism mapped in different linkage groups.
A myb gene, which has been correlated with anthocyanin biosynthesis, cosegregated with berry colour on linkage group 2. The possibility
of associating candidate genes to known position of QTL is discussed for this plant.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Marzia Salmaso and Giulia Malacarne contributed equally to the present work. 相似文献
216.
Nogueira MB Stella V Bordignon J Batista WC Borba Ld Silva LH Hoffmann FG Probst CM Santos CN 《Memórias do Instituto Oswaldo Cruz》2008,103(5):483-488
The reintroduction of dengue virus type 3 (DENV-3) in Brazil in 2000 and its subsequent spread throughout the country was associated with genotype III viruses, the only DENV-3 genotype isolated in Brazil prior to 2002. We report here the co-circulation of two different DENV-3 genotypes in patients living in the Northern region of Brazil during the 2002-2004 epidemics. Complete genomic sequences of viral RNA were determined from these epidemics, and viruses belonging to genotypes V (Southeast Asia/South Pacific) and III were identified. This recent co-circulation of different DENV-3 genotypes in South America may have implications for pathological and epidemiological dynamics. 相似文献
217.
218.
Salvioli S Capri M Santoro A Raule N Sevini F Lukas S Lanzarini C Monti D Passarino G Rose G De Benedictis G Franceschi C 《Biotechnology journal》2008,3(6):740-749
The role of inherited and somatic mutations of mitochondrial DNA (mtDNA) in aging and longevity is complex and highly controversial, owing to its peculiar genetics, including the phenomenon of heteroplasmy. Most of the data on mtDNA and longevity have been obtained on humans and particularly on centenarians, i. e., people who escaped or delayed the major age-related pathologies and reached the extreme limit of human lifespan. In this review we summarize the most recent advances in this field that suggest a consistent role in human longevity of both germ-line inherited and somatically acquired mutations. The particular case of the association with longevity of the somatic C150T mutation is extensively discussed, challenging the tenet that mtDNA mutations are basically detrimental. We also stress several limitations of our present knowledge, regarding the difficulty in extrapolating to humans the results obtained in animal models, owing to a variety of biological differences, including the very limited genetic variability of mtDNA in the strains used in laboratory experiments. The use of high-throughput technologies and the extensive analysis, possibly at the single cell level, of different tissues and cell types derived from the same individual will help in disentangling the complexity of mtDNA in aging and longevity. 相似文献
219.
Obesity is characterized by chronic, low-grade, systemic inflammation, which, in turn, has been associated with anemia of chronic disease. We hypothesized that obesity may be associated with the features of anemia of chronic disease, including low hemoglobin concentration, low serum iron and transferrin saturation (TS), and elevated serum ferritin. We compared normal-weight to overweight and obese adult participants of the third National Health and Nutrition Examination Survey with respect to hemoglobin concentration and levels of serum iron, TS, and ferritin. Measured BMI was used to categorize participants into normal weight (BMI < 25 kg/m(2), n = 6,059), overweight (BMI 25 to <30 kg/m(2), n = 5,108), mildly obese (BMI 30 to <35 kg/m(2), n = 2,366), moderately obese (BMI 35 to <40 kg/m(2), n = 850), and severely obese (BMI > or = 40 kg/m(2), n = 465). After adjustment for age, gender, menstruation, race/ethnicity, education, alcohol consumption, smoking, blood donation, and dietary iron intake, serum ferritin was progressively higher with increasing BMI category, whereas serum iron and TS were progressively lower. However, compared to normal-weight persons, those in all other higher BMI categories did not have a significant change in hemoglobin concentration after adjustment for the above-mentioned confounders. Overweight and obesity were associated with changes in serum iron, TS, and ferritin that would be expected to occur in the setting of chronic, systemic inflammation. However, overweight and obese persons were not more likely to be anemic compared with normal-weight persons. 相似文献
220.
Stella Mokiou 《Biocontrol Science and Technology》2008,18(10):1063-1073
The major hurdle in the production of commercial biocontrol agents (BCAs) has been the lack of production of appropriate formulations. Of particular importance is the conservation of viability and ecological competence after application. With this in mind studies were conducted to develop formulations of P. anomala which would have these attributes. Cells were grown in molasses-based medium modified with proline to different water availability levels (0.98 and 0.96) which significantly increased (up to 50%) the content of trehalose and arabitol in the yeast cells during liquid broth fermentation. The use of isotonic solutions for harvesting the yeast cells further increased the endogenous content of these compatible solutes as well as glycerol. Fluidised bed drying of cells at 30–80°C was carried out for 10 and 20 min and showed that viability was significantly decreased at 70–80°C. A temperature of 50°C for 20 min was found to be best for viability (70%) and moisture content of <10%. Several additives for conservation of viability showed that cotton seed flour+skimmed milk was the best treatment when dried at 50°C. The biocontrol efficacy of formulated P. anomala cells was tested in laboratory scale studies and this showed that they inhibited growth of Penicillium verrucosum and reduce ochratoxin A production in moist wheat grain under some combinations of water availability. Physiologically modified formulated yeast cells with increased levels of trehalose and arabitol gave similar efficacy as fresh cells. This suggests that ecophysiological manipulation of such BCAs can result in improved ecological competence of such formulations and effective biocontrol. 相似文献