184 research outputs found
Transmission of HIV drug resistance and the predicted effect on current first-line regimens in Europe
BACKGROUND: Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD-program systematically collects data to gain insight into TDR occurring in Europe since 2001.
METHODS: Demographic, clinical and virological data from 4,140 antiretroviral-naive HIV-infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002-2007. Baseline susceptibility to antiretroviral drugs was predicted using Stanford HIVdb v7.0.
RESULTS: The overall prevalence of TDR did not change significantly over time and was 8.3% (95%CI 7.2-9.5) in 2008-2010. The most frequent indicators of TDR were NRTI-mutations (4.5%), followed by NNRTI-mutations (2.9%) and PI-mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine respectively, independent of current NRTI backbones.
CONCLUSIONS: Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affecte
Exploring the relationship between macrofungi diversity, abundance, and vascular plant diversity in semi-naturaland managed forests in north-east Hungary
Bone turnover markers in sheep and goat: a review of the scientific literature
Bone turnover markers (BTMs) are product of bone cell activity and are generally divided in bone formation and bone resorption markers. The purpose of this review was to structure the available information on the use of BTMs in studies on small ruminants, especially for monitoring their variations related to diet, exercise, gestation and metabolic lactation state, circadian and seasonal variations, and also during skeletal growth. Pre-clinical and translational studies using BTMs with sheep and goats as animal models in orthopaedic research studies to help in the evaluation of the fracture healing process and osteoporosis research are also described in this review. The available information from the reviewed studies was systematically organized in order to highlight the most promising BTMs in small ruminant research, as well as provide a wide view of the use of sheep and goat as animal models in orthopaedic research, type of markers and commercial assay kits with cross-reactivity in sheep and goat, method of sample and storage of serum and urine for bone turnover markers determination and the usefulness and limitations of bone turnover markers in the different studies, therefore an effective tool for researchers that seek answers to different questions while using BTMs in small ruminants.José Arthur de A. Camassa acknowledges to the
Conselho Nacional de Desenvolvimento Científico
e Tecnológico (CNPq), Brazil, for his PhD
scholarship 202248/2015-1.info:eu-repo/semantics/publishedVersio
Surveillance programs for detection and characterization of emergent pathogens and antimicrobial resistance: results from the Division of Infectious Diseases, UNIFESP
Several epidemiological changes have occurred in the pattern of nosocomial and community acquired infectious diseases during the past 25 years. Social and demographic changes possibly related to this phenomenon include a rapid population growth, the increase in urban migration and movement across international borders by tourists and immigrants, alterations in the habitats of animals and arthropods that transmit disease, as well as the raise of patients with impaired host defense abilities. Continuous surveillance programs of emergent pathogens and antimicrobial resistance are warranted for detecting in real time new pathogens, as well as to characterize molecular mechanisms of resistance. In order to become more effective, surveillance programs of emergent pathogens should be organized as a multicenter laboratory network connected to the main public and private infection control centers. Microbiological data should be integrated to guide therapy, adapting therapy to local ecology and resistance patterns. This paper presents an overview of data generated by the Division of Infectious Diseases, Federal University of São Paulo, along with its participation in different surveillance programs of nosocomial and community acquired infectious diseases.Várias alterações epidemiológicas ocorreram no perfil das doenças infecciosas hospitalares e comunitárias nos últimos 25 anos. Mudanças sociais e demográficas possivelmente relacionadas com esse fenômeno incluem o rápido crescimento populacional, o aumento da migração urbana e deslocamento através de fronteiras internacionais por turistas e imigrantes, alterações nos habitats de animais e artrópodes que transmitem doença assim como o aumento no número de pacientes com deficiências nas respostas de defesa. Os programas contínuos de vigilância de patógenos emergentes e resistência antimicrobiana são necessários para a detecção em tempo real de novos patógenos assim como para caracterizar mecanismos moleculares de resistência. Para serem mais efetivos, os programasde vigilância dos patógenos emergentes devem ser organizados em uma rede de laboratórios multicêntricos ligados aos principais centros de controle de infecções, públicos e privados. Os dados microbiológicos devem ser integrados a guias terapêuticos adaptando práticas terapêuticas à ecologia local eaos padrões de resistência. O artigo apresenta uma revisão dos dados gerados pela Disciplina de Infectologia, Universidade Federal de São Paulo (UNIFESP), contemplando sua participação nos diferentes programas de vigilância de doenças infecciosas hospitalares e adquiridas na comunidade.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Divisão de Doenças InfecciosasUniversidade Federal de São Paulo (UNIFESP) Departamento de Microbiologia, Imunologia e ParasitologiaUNIFESP, Depto. de Medicina Divisão de Doenças InfecciosasUNIFESP, Depto. de Microbiologia, Imunologia e ParasitologiaSciEL
Vasodilator Phosphostimulated Protein (VASP) Protects Endothelial Barrier Function During Hypoxia
The endothelial barrier controls the passage of solutes from the vascular space. This is achieved through active reorganization of the actin cytoskeleton. A central cytoskeletal protein involved into this is vasodilator-stimulated phosphoprotein (VASP). However, the functional role of endothelial VASP during hypoxia has not been thoroughly elucidated. We determined endothelial VASP expression through real-time PCR (Rt-PCR), immunhistochemistry, and Western blot analysis during hypoxia. VASP promoter studies were performed using a PGL3 firefly luciferase containing plasmid. Following approval by the local authorities, VASP−/− mice and littermate controls were subjected to normobaric hypoxia (8% O2, 92% N2) after intravenous injection of Evans blue dye. In in vitro studies, we found significant VASP repression in human microvascular and human umbilical vein endothelial cells through Rt-PCR, immunhistochemistry, and Western blot analysis. The VASP promoter construct demonstrated significant repression in response to hypoxia, which was abolished when the binding of hypoxia-inducible factor 1 alpha was excluded. Exposure of wild-type (WT) and VASP−/− animals to normobaric hypoxia for 4 h resulted in an increase in Evans blue tissue extravasation that was significantly increased in VASP−/− animals compared to WT controls. In summary, we demonstrate here that endothelial VASP holds significant importance for endothelial barrier properties during hypoxia
Muscle and reflex changes with varying joint angle in hemiparetic stroke
<p>Abstract</p> <p>Background</p> <p>Despite intensive investigation, the origins of the neuromuscular abnormalities associated with spasticity are not well understood. In particular, the mechanical properties induced by stretch reflex activity have been especially difficult to study because of a lack of accurate tools separating reflex torque from torque generated by musculo-tendinous structures. The present study addresses this deficit by characterizing the contribution of neural and muscular components to the abnormally high stiffness of the spastic joint.</p> <p>Methods</p> <p>Using system identification techniques, we characterized the neuromuscular abnormalities associated with spasticity of ankle muscles in chronic hemiparetic stroke survivors. In particular, we systematically tracked changes in muscle mechanical properties and in stretch reflex activity during changes in ankle joint angle. Modulation of mechanical properties was assessed by applying perturbations at different initial angles, over the entire range of motion (ROM). Experiments were performed on both paretic and non-paretic sides of stroke survivors, and in healthy controls.</p> <p>Results</p> <p>Both reflex and intrinsic muscle stiffnesses were significantly greater in the spastic/paretic ankle than on the non-paretic side, and these changes were strongly position dependent. The major reflex contributions were observed over the central portion of the angular range, while the intrinsic contributions were most pronounced with the ankle in the dorsiflexed position.</p> <p>Conclusion</p> <p>In spastic ankle muscles, the abnormalities in intrinsic and reflex components of joint torque varied systematically with changing position over the full angular range of motion, indicating that clinical perceptions of increased tone may have quite different origins depending upon the angle where the tests are initiated.</p> <p>Furthermore, reflex stiffness was considerably larger in the non-paretic limb of stroke patients than in healthy control subjects, suggesting that the non-paretic limb may not be a suitable control for studying neuromuscular properties of the ankle joint.</p> <p>Our findings will help elucidate the origins of the neuromuscular abnormalities associated with stroke-induced spasticity.</p
Two genome-wide interaction loci modify the association of nonsteroidal anti-inflammatory drugs with colorectal cancer.
Regular, long-term aspirin use may act synergistically with genetic variants, particularly those in mechanistically relevant pathways, to confer a protective effect on colorectal cancer (CRC) risk. We leveraged pooled data from 52 clinical trial, cohort, and case-control studies that included 30,806 CRC cases and 41,861 controls of European ancestry to conduct a genome-wide interaction scan between regular aspirin/nonsteroidal anti-inflammatory drug (NSAID) use and imputed genetic variants. After adjusting for multiple comparisons, we identified statistically significant interactions between regular aspirin/NSAID use and variants in 6q24.1 (top hit rs72833769), which has evidence of influencing expression of TBC1D7 (a subunit of the TSC1-TSC2 complex, a key regulator of MTOR activity), and variants in 5p13.1 (top hit rs350047), which is associated with expression of PTGER4 (codes a cell surface receptor directly involved in the mode of action of aspirin). Genetic variants with functional impact may modulate the chemopreventive effect of regular aspirin use, and our study identifies putative previously unidentified targets for additional mechanistic interrogation.fals
Genome-wide interaction analysis of folate for colorectal cancer risk.
Background
Epidemiological and experimental evidence suggests that higher folate intake is associated with decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate’s role in CRC.
Objectives
Our aim was to perform a genome-wide interaction analysis to identify genetic variants that may modify the association of folate on CRC risk.
Methods
We applied traditional case-control logistic regression, joint 3-degree of freedom, and a 2-step weighted hypothesis approach to test the interactions of common variants (allele frequency >1%) across the genome and dietary folate, folic acid supplement use, and total folate in relation to risk of CRC in 30,550 cases and 42,336 controls from 51 studies from 3 genetic consortia (CCFR, CORECT, GECCO).
Results
Inverse associations of dietary, total folate, and folic acid supplement with CRC were found (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.90, 0.96; and 0.91; 95% CI: 0.89, 0.94 per quartile higher intake, and 0.82 (95% CI: 0.78, 0.88) for users compared with nonusers, respectively). Interactions (P-interaction < 5×10-8) of folic acid supplement and variants in the 3p25.2 locus (in the region of Synapsin II [SYN2]/tissue inhibitor of metalloproteinase 4 [TIMP4]) were found using traditional interaction analysis, with variant rs150924902 (located upstream to SYN2) showing the strongest interaction. In stratified analyses by rs150924902 genotypes, folate supplementation was associated with decreased CRC risk among those carrying the TT genotype (OR: 0.82; 95% CI: 0.79, 0.86) but increased CRC risk among those carrying the TA genotype (OR: 1.63; 95% CI: 1.29, 2.05), suggesting a qualitative interaction (P-interaction = 1.4×10-8). No interactions were observed for dietary and total folate.
Conclusions
Variation in 3p25.2 locus may modify the association of folate supplement with CRC risk. Experimental studies and studies incorporating other relevant omics data are warranted to validate this finding.fals
Light regulation of metabolic pathways in fungi
Light represents a major carrier of information in nature. The molecular machineries translating its electromagnetic energy (photons) into the chemical language of cells transmit vital signals for adjustment of virtually every living organism to its habitat. Fungi react to illumination in various ways, and we found that they initiate considerable adaptations in their metabolic pathways upon growth in light or after perception of a light pulse. Alterations in response to light have predominantly been observed in carotenoid metabolism, polysaccharide and carbohydrate metabolism, fatty acid metabolism, nucleotide and nucleoside metabolism, and in regulation of production of secondary metabolites. Transcription of genes is initiated within minutes, abundance and activity of metabolic enzymes are adjusted, and subsequently, levels of metabolites are altered to cope with the harmful effects of light or to prepare for reproduction, which is dependent on light in many cases. This review aims to give an overview on metabolic pathways impacted by light and to illustrate the physiological significance of light for fungi. We provide a basis for assessment whether a given metabolic pathway might be subject to regulation by light and how these properties can be exploited for improvement of biotechnological processes
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