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131.
Rafael Piovezan Stéfany Larissa Rosa Matheus Luca Rocha Thiago Salomão de Azevedo Cláudio José Von Zuben 《Journal of vector ecology》2013,38(2):317-325
Because of the high adaptive capacity of mosquitoes, studies that focus on transitional environments become very important, such as those in rural areas, which are considered as bridges between wild diseases and human populations of urban areas. In this study, a survey of the existing species of mosquitoes was performed in an Atlantic Forest area of the city of Santa Bárbara d'Oeste, São Paulo state, Brazil, using traps for immatures and analyzing the frequency and distribution of these insects over the sampling months. Five mosquito species were found: Aedes albopictus (the most frequent species), Aedes aegypti, Aedes fluviatilis, Culex quinquefasciatus, and Toxorhynchites theobaldi. The 4,524 eggs collected in ovitraps showed the presence of the tribe Aedini. Aedes aegypti and Ae. albopictus were identified after larval hatching in the laboratory, with different spatial distributions: the first of which coincides with the area of greatest diversity calculated using the Simpson index, while the second does not. The association of ecological analysis of spatial diversity with simple methods of data collection enables the identification of possible epidemiological risk situations and is a strategy that may be implemented to monitor ecological processes resulting from the interaction among different species of mosquitoes. 相似文献
132.
A. Borzatti Von Loewenstern T. Giordani G. Astuti A. Andreucci 《Plant biosystems》2013,147(3):776-787
The seven Bellevalia species and subspecies known from Italy, representing about 10% of the genus and three out of six sections, were studied. An integrated morphological, karyological and molecular approach was used to infer phylogenetic and systematic relationships among them. B. romana (the generitype) is the most distinctive species on karyotype asymmetry grounds. B. boissieri and B.dubia, usually considered as subspecies of one species (the latter endemic to Sicily), deserve specific status based on biparental nrDNA markers (internal transcribed spacer, ITS), since they do not form a single clade. The allotetraploid endemic B. pelagica, morphologically similar to B. romana, is sister to the latter under parsimony, both in morphological and ITS trees; it is also related with B. dubia, based on karyotype asymmetry and a uniparental cpDNA marker (trnL(UAA)–trnF(GAA) IGS (intergenic spacer)). A second allotetraploid endemic, B. webbiana, is closely related, on morphological, karyological and molecular grounds, with B. boissieri and B. ciliata, and also with B. trifoliata, three species that might all involved in its origin. B. sect. Conicae Feinbr. and sect. Nutantes Feinbr. are here typified, the former (type: B. ciliata) is most likely a synonym of the latter (type: B. trifoliata). 相似文献
133.
Lorena Souza e Silva Aline Mayrink de Miranda Cíntia Lopes de Brito Magalhães Rinaldo Cardoso dos Santos Maria Lúcia Pedrosa Marcelo Eustáquio Silva 《Journal of physiology and biochemistry》2013,69(4):811-820
The present study investigated the underlying mechanism associated with the hypocholesterolemic activity of beta-carotene by examining its effects on the serum lipid profile, fecal cholesterol excretion, and gene expression of the major receptors, enzymes, and transporters involved in cholesterol metabolism. Female Fischer rats were divided into three groups and were fed either a control or a hypercholesterolemic diet supplemented or not supplemented with 0.2 % beta-carotene. After 6 weeks of feeding, blood, livers, and feces were collected for analysis, and quantitative real-time polymerase chain reaction (qRT-PCR) was performed. Dietary supplementation with 0.2 % beta-carotene decreased serum total cholesterol, non-HDL cholesterol, the atherogenic index, and hepatic total lipid and cholesterol contents. These changes were accompanied by an increase in the total lipid and cholesterol contents excreted in the feces. The qRT-PCR analyses demonstrated that the hypercholesterolemic diet promoted a decrease in the gene expression of sterol regulatory element-binding protein 2, 3-hydroxy-3-methylglutaryl CoA reductase, and low-density lipoprotein receptor and an increase in the gene expression of peroxisome proliferator-activated receptor α and cholesterol-7a-hydroxylase. The expression of these genes and gene expression of ATP-binding cassette subfamily G transporters 5and 8 were unaffected by beta-carotene supplementation. In conclusion, the decrease in serum cholesterol and the elevation of fecal cholesterol obtained following beta-carotene administration indicate that this substance may decrease cholesterol absorption in the intestine and increase cholesterol excretion into the feces without a direct effect on the expression of cholesterol metabolism genes. 相似文献
134.
135.
Sandra F. Moreira-Silva Eliana Zandonade Diana O. Frauches Elisa A. Machado Lays Ignacia A. Lopes Lívia L. Duque Polyana P. Querido Angélica E. Miranda 《PloS one》2013,8(12)
Background
Studying diseases associated with AIDS is essential for establishing intervention strategies because comorbidities can lead to death. The objectives were to describe the frequency of comorbidities and verify their distribution according to demographic, epidemiological and clinical data as well as to classify diseases in children and adolescents with AIDS in Vitória, Brazil.Methods
A retrospective cohort study was conducted among children with AIDS, as defined according to the criteria established by the Ministry of Health, who acquired HIV via vertical transmission, were aged 0 to 18 years, and were monitored at a referral hospital from January 2001 to December 2011.Results
A total of 177 patients were included, of whom 97 were female (55%). There were 60 patients (34%) <1 year old, 67 patients (38%) between the ages of 1 and 5, and 50 patients (28%) ≥6 years of age included at the time of admission to the Infectious Diseases Ward. Regarding clinical-immunological classification, 146 patients (82.5%) showed moderate/severe forms of the disease at the time of admission into the Ward, and 26 patients (14.7%) died during the study. The most common clinical signs were hepatomegaly (81.62%), splenomegaly (63.8%), lymphadenopathy (68.4%) and persistent fever (32.8%). The most common comorbidities were anaemia (67.2%), pneumonia/septicaemia/acute bacterial meningitis (ABM) (64.2%), acute otitis media (AOM)/recurrent sinusitis (55.4%), recurrent severe bacterial infections (47.4%) and dermatitis (43.1%). An association between severe clinical-immunological classification and admission to the Ward for children aged less than one year old was found for several comorbidities (p<0.001).Conclusion
Delayed diagnosis was observed because the majority of patients were admitted to the Infectious Diseases Ward at ≥1 year of age and were already presenting with serious diseases. The general paediatrician should be alert to this possibility to make an early diagnosis in children infected with HIV. 相似文献136.
R. Jeremy Woods Michael Hongwei Xie Thomas Spreter Von Kreudenstein Gordon Y. Ng Surjit B. Dixit 《MABS-AUSTIN》2013,5(5):711-722
Bispecific IgG asymmetric (heterodimeric) antibodies offer enhanced therapeutic efficacy, but present unique challenges for drug development. These challenges are related to the proper assembly of heavy and light chains. Impurities such as symmetric (homodimeric) antibodies can arise with improper assembly. A new method to assess heterodimer purity of such bispecific antibody products is needed because traditional separation-based purity assays are unable to separate or quantify homodimer impurities. This paper presents a liquid chromatography-mass spectrometry (LC-MS)-based method for evaluating heterodimeric purity of a prototype asymmetric antibody containing two different heavy chains and two identical light chains. The heterodimer and independently expressed homodimeric standards were characterized by two complementary LC-MS techniques: Intact protein mass measurement of deglycosylated antibody and peptide map analyses. Intact protein mass analysis was used to check molecular integrity and composition. LC-MSE peptide mapping of Lys-C digests was used to verify protein sequences and characterize post-translational modifications, including C-terminal truncation species. Guided by the characterization results, a heterodimer purity assay was demonstrated by intact protein mass analysis of pure deglycosylated heterodimer spiked with each deglycosylated homodimeric standard. The assay was capable of detecting low levels (2%) of spiked homodimers in conjunction with co-eluting half antibodies and multiple mass species present in the homodimer standards and providing relative purity differences between samples. Detection of minor homodimer and half-antibody C-terminal truncation species at levels as low as 0.6% demonstrates the sensitivity of the method. This method is suitable for purity assessment of heterodimer samples during process and purification development of bispecific antibodies, e.g., clone selection. 相似文献
137.
138.
Miranda de Graaf Sander Herfst Jamil Aarbiou Peter C. Burgers Fatiha Zaaraoui-Boutahar Maarten Bijl Wilfred van IJcken Eefje J. A. Schrauwen Albert D. M. E. Osterhaus Theo M. Luider Bob J. Scholte Ron A. M. Fouchier Arno C. Andeweg 《PloS one》2013,8(3)
Human metapneumovirus (HMPV) encodes a small hydrophobic (SH) protein of unknown function. HMPV from which the SH open reading frame was deleted (HMPVΔSH) was viable and displayed similar replication kinetics, cytopathic effect and plaque size compared with wild type HMPV in several cell-lines. In addition, no differences were observed in infection efficiency or cell-to-cell spreading in human primary bronchial epithelial cells (HPBEC) cultured at an air-liquid interphase. Host gene expression was analyzed in A549 cells infected with HMPV or HMPVΔSH using microarrays and mass spectrometry (MS) based techniques at multiple time points post infection. Only minor differences were observed in mRNA or protein expression levels. A possible function of HMPV SH as apoptosis blocker, as proposed for several members of the family Paramyxoviridae, was rejected based on this analysis. So far, a clear phenotype of HMPV SH deletion mutants in vitro at the virus and host levels is absent. 相似文献
139.
J. Jaime Miranda Victor M. Herrera Julio A. Chirinos Luis F. Gómez Pablo Perel Rafael Pichardo Angel González José R. Sánchez Catterina Ferreccio Ximena Aguilera Eglé Silva Myriam Oróstegui Josefina Medina-Lezama Cynthia M. Pérez Erick Suárez Ana P. Ortiz Luis Rosero Noberto Schapochnik Zulma Ortiz Daniel Ferrante Juan P. Casas Leonelo E. Bautista 《PloS one》2013,8(1)
Background
Limited knowledge on the prevalence and distribution of risk factors impairs the planning and implementation of cardiovascular prevention programs in the Latin American and Caribbean (LAC) region.Methods and Findings
Prevalence of hypertension, diabetes mellitus, abnormal lipoprotein levels, obesity, and smoking were estimated from individual-level patient data pooled from population-based surveys (1998–2007, n = 31,009) from eight LAC countries and from a national survey of the United States (US) population (1999–2004) Age and gender specific prevalence were estimated and age-gender adjusted comparisons between both populations were conducted. Prevalence of diabetes mellitus, hypertension, and low high-density lipoprotein (HDL)-cholesterol in LAC were 5% (95% confidence interval [95% CI]: 3.4, 7.9), 20.2% (95% CI: 12.5, 31), and 53.3% (95% CI: 47, 63.4), respectively. Compared to LAC region’s average, the prevalence of each risk factor tended to be lower in Peru and higher in Chile. LAC women had higher prevalence of obesity and low HDL-cholesterol than men. Obesity, hypercholesterolemia, and hypertriglyceridemia were more prevalent in the US population than in LAC population (31 vs. 16.1%, 16.8 vs. 8.9%, and 36.2 vs. 26.5%, respectively). However, the prevalence of low HDL-cholesterol was higher in LAC than in the US (53.3 vs. 33.7%).Conclusions
Major cardiovascular risk factors are highly prevalent in LAC region, in particular low HDL-cholesterol. In addition, marked differences do exist in this prevalence profile between LAC and the US. The observed patterns of obesity-related risk factors and their current and future impact on the burden of cardiovascular diseases remain to be explained. 相似文献140.
Jennifer L. Green Matthieu Bauer Kyu Won Yum Yao-Cheng Li Miranda L. Cox Karl Willert Geoffrey M. Wahl 《PloS one》2013,8(3)
Functional and mechanistic studies of Wnt signaling have been severely hindered by the inaccessibility of bioactive proteins. To overcome this long-standing barrier, we engineered and characterized a panel of Chinese hamster ovary (CHO) cell lines with inducible transgenes encoding tagged and un-tagged human WNT1, WNT3A, WNT5A, WNT7A, WNT11, WNT16 or the soluble Wnt antagonist Fzd8CRD, all integrated into an identical genomic locus. Using a quantitative real-time bioluminescence assay, we show that cells expressing WNT1, 3A and 7A stimulate Wnt/beta-catenin reporter activity, while the other WNT expressing cell lines interfere with this activation. Additionally, in contrast to WNT3A, WNT1 only exhibits activity when cell-associated, and thus only signals to neighboring cells. The reporter assay also revealed a rapid decline of Wnt activity at 37°C, indicating that Wnt activity is highly labile. These engineered cell lines will reduce the cost of making and purifying Wnt proteins and serve as a continuous, reliable and regulatable source of Wnts to research laboratories around the world. 相似文献