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61.
B-type natriuretic peptide (BNP) is a diagnostic and prognostic tool in heart failure and also in Chagas disease, which is caused by the protozoan Trypanosoma cruzi and has cardiomyopathy as a main feature. BNP lipolytic actions and T. cruzi infection in the adipose tissue have been recently described. We aim to investigate the relationship between BNP and anthropometric measures and whether it is influenced by T. cruzi infection. We measured BNP, body mass index (BMI), waist circumference (WC), triceps skin-fold thickness (TSF) and performed serological, biochemical and electrocardiographic exams in 1398 subjects (37.5% infected with T. cruzi) in a community-dwelling elderly population in Bambui city, Brazil. Linear multivariate regression analysis was performed to investigate determinants of BNP levels. BNP levels were significantly (p < 0.05) higher in T. cruzi-infected subjects than in the non-infected group (median = 121 and 64 pg/mL, respectively). BMI, WC and TSF in infected subjects were significantly lower than those in non-infected subjects (24.3 vs. 25.5 kg/m2; 89.2 vs. 92.4 cm; and 14.5 vs. 16.0 mm, respectively). There was an inverse relationship between BNP levels and BMI (b = −0.018), WC (b = −0.005) and TSF (b = −0.193) levels. Infected and non-infected groups showed similar inverse relationships between BNP and BMI (b = −0.021 and b = −0.015, respectively). In conclusion, there was an inverse relationship between BNP levels and the anthropometric measures. Despite the actions in the adipose tissue, T. cruzi infection did not modify the associations between BNP and BMI, suggesting that body mass does not modify the accuracy of BNP in Chagas disease. 相似文献
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63.
María Isabel Gómez Jiménez Carlos E. Sarmiento María Fernanda Díaz Alexander Chautá Andrés Peraza Augusto Ramírez Katja Poveda 《Entomologia Experimentalis et Applicata》2014,153(1):24-33
It is expected that females preferentially oviposit on plant hosts that allow for optimal larval performance. However, this expectation contradicts empirical evidence where adults do not always choose the best host for their descendants. Recent evidence suggests that females’ host selection depends on the number of potential hosts. Females from oligophagous species seem to be able to choose an appropriate host in terms of larval performance, whereas in polyphagous species, adult oviposition preference is not related with larval performance. This suggests that larvae in polyphagous species could be taking a more active role in host selection than their mothers. Here, we evaluated the oviposition preference and the larval preference and performance of two polyphagous species of economic importance, Copitarsia decolora (Guenée) (Lepidoptera: Noctuidae: Cuculliinae) and Peridroma saucia (Hübner) (Lepidoptera: Noctuidae: Noctuinae), on eight species of cultivated plants. In laboratory and greenhouse choice assays, we tested adult preference for oviposition and larval preference at 1 and 24 h. Larval performance was measured in terms of survival to adulthood, length of larval period, and pupal weight. We found that both adult females and larvae actively choose their hosts and that the larval preference toward the hosts is related to the females’ preference in both herbivore species. However, the females and larvae did not preferentially select the host with the best larval performance, indicating that larval performance is not related to female or larval preference and that other selective pressures are influencing the choice of the host plant in these two species. 相似文献
64.
Fernanda Genre Raquel López-Mejías Mercedes García-Bermúdez Santos Casta?eda Carlos González-Juanatey Javier Llorca Alfonso Corrales Bego?a Ubilla José A. Miranda-Filloy Trinitario Pina Carmen Gómez-Vaquero Luis Rodríguez-Rodríguez Benjamín Fernández-Gutiérrez Alejandro Balsa Dora Pascual-Salcedo Francisco J. López-Longo Patricia Carreira Ricardo Blanco Isidoro González-álvaro Javier Martín Miguel A. González-Gay 《PloS one》2014,9(9)
Introduction
Rheumatoid arthritis is an inflammatory disease with high incidence of cardiovascular disease due to accelerated atherosclerosis. Osteoprotegerin (OPG) has been associated with increased risk of atherosclerotic disease in the general population. Several polymorphisms in the OPG gene with functional effects on cardiovascular disease in non-rheumatic individuals have been described. Therefore, we aimed to analyze the effect of three of these functional OPG polymorphisms on the risk of cardiovascular disease in a large and well-characterized cohort of Spanish patients with rheumatoid arthritis.Methods
Three OPG gene variants (rs3134063, rs2073618 and rs3134069) were genotyped by TaqMan assays in 2027 Spanish patients with rheumatoid arthritis. Anti-cyclic citrullinated peptide (anti-CCP) antibody testing was positive in 997 of 1714 tested. Also, 18.3% of the whole series had experienced cardiovascular events, including 5.4% with cerebrovascular accidents. The relationship between OPG variants and cardiovascular events was assessed using Cox regression.Results
No association between OPG gene variants and cardiovascular disease was observed in the whole group of rheumatoid arthritis patients or in anti-CCP positive patients. Nevertheless, a protective effect of CGA haplotype on the risk of cardiovascular disease in general, and specifically in the risk of cerebrovascular complications after adjusting for sex, age at disease diagnosis and traditional cardiovascular risk factors was disclosed in anti-CCP negative patients (HR = 0.54; 95%CI: 0.31–0.95; p = 0.032 and HR = 0.17; 95%CI: 0.04–0.78; p = 0.022, respectively).Conclusion
Our results indicate a protective effect of the OPG CGA haplotype on cardiovascular risk, mainly due to a protective effect against cerebrovascular events in anti-CCP negative rheumatoid arthritis patients. 相似文献65.
Letícia B. Rocha Anna R. R. Santos Danielle D. Munhoz Lucas T. A. Cardoso Daniela E. Luz Fernanda B. Andrade Denise S. P. Q. Horton Waldir P. Elias Roxane M. F. Piazza 《PLoS neglected tropical diseases》2014,8(9)
Background
Enteropathogenic and enterohemorrhagic Escherichia coli (EPEC/EHEC) are human intestinal pathogens responsible for diarrhea in both developing and industrialized countries. In research laboratories, EPEC and EHEC are defined on the basis of their pathogenic features; nevertheless, their identification in routine laboratories is expensive and laborious. Therefore, the aim of the present work was to develop a rapid and simple assay for EPEC/EHEC detection. Accordingly, the EPEC/EHEC-secreted proteins EspA and EspB were chosen as target antigens.Methodology
First, we investigated the ideal conditions for EspA/EspB production/secretion by ELISA in a collection of EPEC/EHEC strains after cultivating bacterial isolates in Dulbecco’s modified Eagle’s medium (DMEM) or DMEM containing 1% tryptone or HEp-2 cells-preconditioned DMEM, employing either anti-EspA/anti-EspB polyclonal or monoclonal antibodies developed and characterized herein. Subsequently, a rapid agglutination latex test (RALT) was developed and tested with the same collection of bacterial isolates.Principal findings
EspB was defined as a biomarker and its corresponding monoclonal antibody as the tool for EPEC/EHEC diagnosis; the production of EspB was better in DMEM medium. RALT assay has the sensitivity and specificity required for high-impact diagnosis of neglected diseases in the developing world.Conclusion
RALT assay described herein can be considered an alternative assay for diarrhea diagnosis in low-income countries since it achieved 97% sensitivity, 98% specificity and 97% efficiency. 相似文献66.
67.
Nucleotide sequence differentiation of argentine isolates of the mosquito parasitic nematode Strelkovimermis spiculatus (Nematoda: Mermithidae) 下载免费PDF全文
68.
Sally Hamour Poh-Yi Gan Ruth Pepper Fernanda Florez Barros Hsu-Han Wang Kim O’Sullivan Yoichiro Iwakura Terence Cook Charles Pusey Stephen Holdsworth Alan Salama 《PloS one》2015,10(8)
IL-17 is a pro-inflammatory cytokine implicated in the pathogenesis of glomerulonephritis and IL-17 deficient mice are protected from nephrotoxic nephritis. However, a regulatory role for IL-17 has recently emerged. We describe a novel protective function for IL-17 in the kidney. Bone marrow chimeras were created using wild-type and IL-17 deficient mice and nephrotoxic nephritis was induced. IL-17 deficient hosts transplanted with wild-type bone marrow had worse disease by all indices compared to wild-type to wild-type bone marrow transplants (serum urea p<0.05; glomerular thrombosis p<0.05; tubular damage p<0.01), suggesting that in wild-type mice, IL-17 production by renal cells resistant to radiation is protective. IL-17 deficient mice transplanted with wild-type bone marrow also had a comparatively altered renal phenotype, with significant differences in renal cytokines (IL-10 p<0.01; IL-1β p<0.001; IL-23 p<0.01), and macrophage phenotype (expression of mannose receptor p<0.05; inducible nitric oxide synthase p<0.001). Finally we show that renal mast cells are resistant to radiation and produce IL-17, suggesting they are potential local mediators of disease protection. This is a novel role for intrinsic cells in the kidney that are radio-resistant and produce IL-17 to mediate protection in nephrotoxic nephritis. This has clinical significance as IL-17 blockade is being trialled as a therapeutic strategy in some autoimmune diseases. 相似文献
69.
Fernanda Ana-Sosa-Batiz Hillary Vanderven Sinthujan Jegaskanda Angus Johnston Steven Rockman Karen Laurie Ian Barr Patrick Reading Marit Lichtfuss Stephen J. Kent 《PloS one》2016,11(4)
BackgroundImmunity to human influenza A virus (IAV) infection is only partially understood. Broadly non-neutralizing antibodies may assist in reducing disease but have not been well characterized.MethodsWe measured internalization of opsonized, influenza protein-coated fluorescent beads and live IAV into a monocytic cell line to study antibody-dependent phagocytosis (ADP) against multiple influenza hemagglutinin (HA) subtypes. We analyzed influenza HA-specific ADP in healthy human donors, in preparations of intravenous immunoglobulin (IVIG), and following IAV infection of humans and macaques.ResultsWe found that both sera from healthy adults and IVIG preparations had broad ADP to multiple seasonal HA proteins and weak cross-reactive ADP to non-circulating HA proteins. The ADP in experimentally influenza-infected macaque plasma and naturally influenza-infected human sera mediated phagocytosis of both homologous and heterologous IAVs. Further, the IAV phagocytosed in an antibody-mediated manner had reduced infectivity in vitro.ConclusionWe conclude that IAV infections in humans and macaques leads to the development of influenza-specific ADP that can clear IAV infection in vitro. Repeated exposure of humans to multiple IAV infections likely leads to the development of ADP that is cross-reactive to strains not previously encountered. Further analyses of the protective capacity of broadly reactive influenza-specific ADP is warranted. 相似文献
70.
Eulália Silva dos Santos Pinheiro Fernanda Costa de Queirós Pedro Montoya Cleber Luz Santos Marion Alves do Nascimento Clara Hikari Ito Manuela Silva David Barros Nunes Santos Silvia Benevides José Garcia Vivas Miranda Katia Nunes Sá Abrah?o Fontes Baptista 《PloS one》2016,11(2)
The main objective of this study is to review and summarize recent findings on electroencephalographic patterns in individuals with chronic pain. We also discuss recent advances in the use of quantitative Electroencephalography (qEEG) for the assessment of pathophysiology and biopsychosocial factors involved in its maintenance over time. Data collection took place from February 2014 to July 2015 in PubMed, SciELO and PEDro databases. Data from cross-sectional studies and longitudinal studies, as well as clinical trials involving chronic pain participants were incorporated into the final analysis. Our primary findings related to chronic pain were an increase of theta and alpha EEG power at rest, and a decrease in the amplitude of evoked potentials after sensory stimulation and cognitive tasks. This review suggests that qEEG could be considered as a simple and objective tool for the study of brain mechanisms involved in chronic pain, as well as for identifying the specific characteristics of chronic pain condition. In addition, results show that qEEG probably is a relevant outcome measure for assessing changes in therapeutic studies. 相似文献