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61.
62.
María Elvira Balcells Patricia García Paulina Meza Carlos Pe?a Marcela Cifuentes David Couvin Nalin Rastogi 《PloS one》2015,10(2)
Tuberculosis (TB) remains a significant public health problem worldwide, but the ecology of the prevalent mycobacterial strains, and their transmission, can vary depending on country and region. Chile is a country with low incidence of TB, that has a geographically isolated location in relation to the rest of South American countries due to the Andes Mountains, but recent migration from neighboring countries has changed this situation. We aimed to assess the genotypic diversity of Mycobacterium tuberculosis complex (MTBC) strains in Santiago, Chile, and compare with reports from other Latin-American countries. We analyzed MTBC isolates from pulmonary tuberculosis cases collected between years 2008 and 2013 in Central Santiago, using two genotyping methods: spoligotyping and 12-loci mycobacterial interspersed repetitive unit-variable number of tandem repeats (MIRU-VNTRs). Data obtained were analyzed and compared to the SITVIT2 database. Mean age of the patients was 47.5 years and 61% were male; 11.6% were migrants. Of 103 strains (1 isolate/patient) included, there were 56 distinct spoligotype patterns. Of these, 16 strains (15.5%) corresponded to orphan strains in the SITVIT2 database, not previously reported. Latin American and Mediterranean (LAM) (34%) and T (33%) lineages were the most prevalent strains, followed by Haarlem lineage (16.5%). Beijing family was scarcely represented with only two cases (1.9%), one of them isolated from a Peruvian migrant. The most frequent clustered spoligotypes were SIT33/LAM3 (10.7%), SIT53/T1 (8.7%), SIT50/H3 (7.8%), and SIT37/T3 (6.8%). We conclude that LAM and T genotypes are the most prevalent genotypes of MTBC in Santiago, Chile, and together correspond to almost two thirds of analyzed strains, which is similar to strain distribution reported from other countries of Latin America. Nevertheless, the high proportion of SIT37/T3, which was rarely found in other Latin American countries, may underline a specific history or demographics of Chile related to probable human migrations and evolutions. 相似文献
63.
Blunted suppression of acyl‐ghrelin in response to fructose ingestion in obese adolescents: The role of insulin resistance 下载免费PDF全文
64.
Laura Holzmeyer Marco Duretto Darren Crayn Elvira H?randl Margaret Heslewood Janani Jayanthan Marc S. Appelhans 《PloS one》2015,10(8)
Background
The genus Acronychia (Citrus family, Rutaceae) contains 49 species of trees and shrubs that are found mainly in rain forest. The genus has a large distributional range from mainland southern Asia to Australia and New Caledonia, but most species are endemic to either New Guinea or Australia. This study aimed to provide the first detailed molecular phylogeny of Acronychia and use it to test the taxonomic value of fruit morphological characters, and infer the historical biogeography of the genus.Methodology
Phylogenetic analyses (Bayesian Inference, Maximum Likelihood) were undertaken on nucleotide sequence data from two plastid (psbA-trnH, trnL-trnF) and three nuclear markers (ETS, ITS, NIAi3) from 29 Acronychia species (59% of the genus) and representatives of related genera.Results and Conclusions
The results indicate that the South-East Asian genus Maclurodendron is nested phylogenetically within Acronychia and must be synonymized to render Acronychia monophyletic. Fruit morphological characters have been used previously to infer relationships within Acronychia and our analyses show that these characters are informative for some subclades but are homoplasious for the group as a whole. Apocarpous fruits are the ancestral state in Acronychia and subapocarpous and fully syncarpous fruits are derived. The unisexual flowers of Maclurodendron are derived from bisexual flowers, which are found in all species of Acronychia as well as its relatives. Acronychia probably first evolved on Australia with range expansion to New Guinea via stepping-stone dispersal or direct land connections within the Sahul Shelf, followed by two independent dispersals to areas west of New Guinea. Most species of Acronychia occur in either Australia or New Guinea, but no species occurs in both regions. This is surprising given the close proximity of the landmasses, but might be explained by ecological factors. 相似文献65.
Fernando Abad-Franch Elvira Zamora-Perea Gon?alo Ferraz Samael D. Padilla-Torres Sérgio L. B. Luz 《PLoS neglected tropical diseases》2015,9(4)
Background
Mosquito-borne pathogens pose major public health challenges worldwide. With vaccines or effective drugs still unavailable for most such pathogens, disease prevention heavily relies on vector control. To date, however, mosquito control has proven difficult, with low breeding-site coverage during control campaigns identified as a major drawback. A novel tactic exploits the egg-laying behavior of mosquitoes to have them disseminate tiny particles of a potent larvicide, pyriproxyfen (PPF), from resting to breeding sites, thus improving coverage. This approach has yielded promising results at small spatial scales, but its wider applicability remains unclear.Methodology/Principal Findings
We conducted a four-month trial within a 20-month study to investigate mosquito-driven dissemination of PPF dust-particles from 100 ‘dissemination stations’ (DSs) deployed in a 7-ha sub-area to surveillance dwellings and sentinel breeding sites (SBSs) distributed over an urban neighborhood of about 50 ha. We assessed the impact of the trial by measuring juvenile mosquito mortality and adult mosquito emergence in each SBS-month. Using data from 1,075 dwelling-months, 2,988 SBS-months, and 29,922 individual mosquitoes, we show that mosquito-disseminated PPF yielded high coverage of dwellings (up to 100%) and SBSs (up to 94.3%). Juvenile mosquito mortality in SBSs (about 4% at baseline) increased by over one order of magnitude during PPF dissemination (about 75%). This led to a >10-fold decrease of adult mosquito emergence from SBSs, from approximately 1,000–3,000 adults/month before to about 100 adults/month during PPF dissemination.Conclusions/Significance
By expanding breeding-site coverage and boosting juvenile mosquito mortality, a strategy based on mosquito-disseminated PPF has potential to substantially enhance mosquito control. Sharp declines in adult mosquito emergence can lower vector/host ratios, reducing the risk of disease outbreaks. This approach is a very promising complement to current and novel mosquito control strategies; it will probably be especially relevant for the control of urban disease vectors, such as Aedes and Culex species, that often cause large epidemics. 相似文献66.
67.
Caterina Longo Simonetta Piana Aimilios Lallas Elvira Moscarella Mara Lombardi Margherita Raucci Giovanni Pellacani Giuseppe Argenziano 《PloS one》2015,10(9)
Background
Several studies have demonstrated the benefit of integrating clinical with pathologic information, to obtain a confident diagnosis for melanocytic tumors. However, all those studies were conducted retrospectively and no data are currently available about the role of a clinical-pathologic correlation approach on a daily basis in clinical practice.Aim of the Study
In our study, we evaluated the impact of a routine clinical-pathologic correlation approach for difficult skin tumors seen over 3 years in a tertiary referral center.Results
Interestingly, a re-appraisal was requested for 158 out of 2015 (7.7%) excised lesions because clinical-pathologic correlation was missing. Of note, in 0.6% of them (13 out of 2045) the first histologic diagnosis was revised in the light of clinical information that assisted the Pathologist to re-evaluate the histopathologic findings that might be bland or inconspicuous per se.Conclusion
In conclusion, our study demonstrated that an integrated approach involving clinicians and pathologists allows improving management of selected patients by shifting from a simply disease-focused management (melanoma versus nevus) to a patient-centered approach. 相似文献68.
Background and Aims
Asexual organisms are more widespread in previously glaciated areas than their sexual relatives (‘geographical parthenogenesis’). In plants, this pattern is probably dependent on reproductive isolation and stability of cytotypes within their respective distribution areas. Both partial apomixis and introgressive hybridization potentially destabilize the spatial separation of sexual and apomictic populations. The wide distribution of apomicts may be further enhanced by uniparental reproduction which is advantageous for colonization. These factors are studied in the alpine species Ranunculus kuepferi.Methods
Geographical distribution, diversity and mode of reproduction of cytotypes were assessed using flow cytometry and flow cytometric seed screening on samples from 59 natural populations of Ranunculus kuepferi. Seed set of cytotypes was compared in the wild.Key Results
Diploid sexuals are confined to the south-western parts of the Alps, while tetraploid apomicts dominate in previously glaciated and in geographically isolated areas despite a significantly lower fertility. Other cytotypes (3x, 5x and 6x) occur mainly in the sympatric zone, but without establishing populations. The tetraploids are predominantly apomictic, but also show a partial apomixis via an uncoupling of apomeiosis and parthenogenesis in the seed material. Both pseudogamy and autonomous endosperm formation are observed which may enhance uniparental reproduction.Conclusions
Diploids occupy a glacial relic area and resist introgression of apomixis, probably because of a significantly higher seed set. Among the polyploids, only apomictic tetraploids form stable populations; the other cytotypes arising from partial apomixis fail to establish, probably because of minority cytotype disadvantages. Tetraploid apomicts colonize previously devastated and also distant areas via long-distance dispersal, confirming Baker''s law of an advantage of uniparental reproduction. It is concluded that stability of cytotypes and of modes of reproduction are important factors for establishing a pattern of geographical parthenogenesis. 相似文献69.
María Isabel Burgos Alves Francisco Avilés Plaza Rebeca Martínez-Tomás María Sánchez-Campillo Elvira Larqué Francisca Pérez-Llamas Pedro Martínez Hernández Soledad Parra Pallarés 《Journal of physiology and biochemistry》2010,66(3):221-227
The biological effects of oxidized LDL (oxLDL) may contribute to initiation and progression of the atherosclerotic process,
and the association between cardiovascular disease and oxidation of LDL has been largely demonstrated. The objectives of this
study were to establish the reference values of oxidative stress biomarkers in a young healthy Spanish population to determine
the concentration of oxLDL and its relationship with lipid profile and with these biomarkers. oxLDL, F2-isoprostanes, protein carbonyls (PC), and 8-hydroxy-2′-deoxyguanosine (8-OHdG) were determinate by ELISA in 72 healthy subjects.
Antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione reductase (GR) were carried
out on a Hitachi 912 analyzer; lipid profile were assayed using automated systems (Cobas 711, Roche Diagnostics). All statistics
were analyzed by using SPSS for Windows 15.0. SPSS Inc, Chicago, IL, USA. (Normal mean reference values): oxLDL (63.23 ± 16.23
U/L), (Male/Female 68.06 ± 17.69/58.39 ± 13.6 U/L), F2-isoprostanes (2.26 ± 0.9 μg/g creatinine), PC (0.34 ± 0.15 nmol/mg), 8-OHdG (23.27 ± 10.58 ng/ml), SOD (931.97 ± 271.09 U/g
Hb), GR (46.56 ± 11.68 U/L), GPx (27.58 ± 6.89 U/gHb (Male/Female 25.91 ± 5.03/29.2 ± 8.07 U/L)). OxLDL (63.23 U/L) was significantly
(p < 0.05) positively correlated with BMI (22.53 Kg/m2), total cholesterol (175.79 mg/dl), triglycerides (87.58 mg/dl), LDL cholesterol (96.25 mg/dl), and uric acid (4.78 mg/dl),
while negatively correlated with HDL-cholesterol (62.25 mg/dl). We have found different correlation between oxLDL and isoprostanes
by gender with the rest of parameters. Normal reference values have been found significantly different for oxLDL and GPx by
gender. Oxidized LDL is correlated with lipid profile but not with the oxidative stress biomarkers. Urinary isoprostanes are
positively correlated with triglycerides and negatively with GR and GPx. 相似文献
70.
Nimrod Heldman Ohad Vonshak Carolyn S Sevier Elvira Vitu Tevie Mehlman Deborah Fass 《Protein science : a publication of the Protein Society》2010,19(10):1863-1876
Ero1p is the primary catalyst of disulfide bond formation in the yeast endoplasmic reticulum (ER). Ero1p contains a pair of essential disulfide bonds that participate directly in the electron transfer pathway from substrate thiol groups to oxygen. Remarkably, elimination of certain other Ero1p disulfides by mutation enhances enzyme activity. In particular, the C150A/C295A Ero1p mutant exhibits increased thiol oxidation in vitro and in vivo and interferes with redox homeostasis in yeast cells by hyperoxidizing the ER. Inhibitory disulfides of Ero1p are thus important for enzyme regulation. To visualize the differences between de-regulated and wild-type Ero1p, we determined the crystal structure of Ero1p C150A/C295A. The structure revealed local changes compared to the wild-type enzyme around the sites of mutation, but no conformational transitions within 25 Å of the active site were observed. To determine how the C150—C295 disulfide nonetheless participates in redox regulation of Ero1p, we analyzed using mass spectrometry the changes in Ero1p disulfide connectivity as a function of time after encounter with reducing substrates. We found that the C150—C295 disulfide sets a physiologically appropriate threshold for enzyme activation by guarding a key neighboring disulfide from reduction. This study illustrates the diverse and interconnected roles that disulfides can play in redox regulation of protein activity. 相似文献