79 research outputs found

    Kerteszia subgenus of Anopheles associated with the Brazilian Atlantic rainforest:current knowledge and future challenges

    Get PDF
    Background: The Atlantic rainforest ecosystem, where bromeliads are abundant, provides an excellent environment for Kerteszia species, because these anophelines use the axils of those plants as larval habitat. Anopheles (K.) cruzii and Anopheles (K.) bellator are considered the primary vectors of malaria in the Atlantic forest. Although the incidence of malaria has declined in some areas of the Atlantic forest, autochthonous cases are still registered every year, with Anopheles cruzii being considered to be a primary vector of both human and simian Plasmodium. Methods: Recent publications that addressed ecological aspects that are important for understanding the involvement of Kerteszia species in the epidemiology of malaria in the Atlantic rainforest in the Neotropical Region were analysed. Conclusion: The current state of knowledge about Kerteszia species in relation to the Atlantic rainforest ecosystem was discussed. Emphasis was placed on ecological characteristics related to epidemiological aspects of this group of mosquitoes. The main objective was to investigate biological aspects of the species that should be given priority in future studie

    Influence of the Stability of a Fused Protein and Its Distance to the Amyloidogenic Segment on Fibril Formation

    Get PDF
    Conversion of native proteins into amyloid fibrils is irreversible and therefore it is difficult to study the interdependence of conformational stability and fibrillation by thermodynamic analyses. Here we approached this problem by fusing amyloidogenic poly-alanine segments derived from the N-terminal domain of the nuclear poly (A) binding protein PABPN1 with a well studied, reversibly unfolding protein, CspB from Bacillus subtilis. Earlier studies had indicated that CspB could maintain its folded structure in fibrils, when it was separated from the amyloidogenic segment by a long linker. When CspB is directly fused with the amyloidogenic segment, it unfolds because its N-terminal chain region becomes integrated into the fibrillar core, as shown by protease mapping experiments. Spacers of either 3 or 16 residues between CspB and the amyloidogenic segment were not sufficient to prevent this loss of CspB structure. Since the low thermodynamic stability of CspB (ΔGD = 12.4 kJ/mol) might be responsible for unfolding and integration of CspB into fibrils, fusions with a CspB mutant with enhanced thermodynamic stability (ΔGD = 26.9 kJ/mol) were studied. This strongly stabilized CspB remained folded and prevented fibril formation in all fusions. Our data show that the conformational stability of a linked, independently structured protein domain can control fibril formation

    Inhibition of ER stress-mediated apoptosis in macrophages by nuclear-cytoplasmic relocalization of eEF1A by the HIV-1 Nef protein

    Get PDF
    HIV-1 Nef protein has key roles at almost all stages of the viral life cycle. We assessed the role of the Nef/eEF1A (eukaryotic translation elongation factor 1-alpha) complex in nucleocytoplasmic shuttling in primary human macrophages. Nuclear retention experiments and inhibition of the exportin-t (Exp-t) pathway suggested that cytoplasmic relocalization of eEF1A, mediated by Exp-t, occurs in Nef-treated monocyte-derived macrophages (MDMs). We observed the presence of tRNA in the Nef/eEF1A complexes. Nucleocytoplasmic relocalization of the Nef/eEF1A complexes prevented stress-induced apoptosis of MDMs treated with brefeldin-A. Blockade of stress-induced apoptosis of MDMs treated with HIV-1 Nef resulted from enhanced nucleocytoplasmic transport of eEF1A with decreased release of mitochondrial cytochrome c, and from increased tRNA binding to cytochrome c, ultimately leading to an inhibition of caspase activation. Our results indicate that HIV-1 Nef, through the nucleocytoplasmic relocalization of eEF1A and tRNAs, enhances resistance to stress-induced apoptosis in primary human macrophages

    The multiple meanings of "wheezing": a questionnaire survey in Portuguese for parents and health professionals

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Most epidemiological studies on pediatric asthma rely on the report of "wheezing" in questionnaires. Our aim was to investigate the understanding of this term by parents and health professionals.</p> <p>Methods</p> <p>A cross-sectional survey was carried out in hospital and community settings within the south of Portugal. Parents or caregivers self-completed a written questionnaire with information on social characteristics and respiratory history. Multiple choice questions assessed their understanding of "wheezing". Health professionals (physicians, nurses and physiotherapists) were given an adapted version. We used bivariate analysis and multivariate models to study associations between definitions of "wheezing" and participants' characteristics.</p> <p>Results</p> <p>Questionnaires from 425 parents and 299 health professionals were included. The term "wheezing" was not recognized by 34% of parents, more frequently those who were younger (OR 0.4 per 10-year increment, 95% CI 0.3-0.7), had lower education (OR 3.3, 95% CI 1.5-7.4), and whose children had no history of respiratory disease (OR 4.6, 95% CI 2.5-8.7) (all ORs adjusted). 31% of parents familiar with "wheezing" either did not identify it as a sound, or did not locate it to the chest, while tactile (40%) and visual (34%) cues to identify "wheezing" were frequently used. Nurses reported using visual stimuli and overall assessments more often than physicians (p < 0.01). The geographical location was independently associated with how parents recognized and described "wheezing".</p> <p>Conclusions</p> <p>Different meanings for "wheezing" are recognized in Portuguese language and may be influenced by education, respiratory history and regional terminology. These findings are likely applicable to other non-English languages, and suggest the need for more accurate questionnaires and additional objective measurement instruments to study the epidemiology of wheezing disorders.</p

    The importance of perceptual experience in the esthetic appreciation of the body.

    Get PDF
    Several studies suggest that sociocultural models conveying extreme thinness as the widespread ideal of beauty exert an important influence on the perceptual and emotional representation of body image. The psychological mechanisms underlying such environmental influences, however, are unclear. Here, we utilized a perceptual adaptation paradigm to investigate how perceptual experience modulates body esthetic appreciation. We found that the liking judgments of round bodies increased or decreased after brief exposure to round or thin bodies, respectively. No change occurred in the liking judgments of thin bodies. The results suggest that perceptual experience may shape our esthetic appreciation to favor more familiar round body figures. Importantly, individuals with more deficits in interoceptive awareness were less prone to increase their liking ratings of round bodies after exposure, suggesting a specific risk factor for the susceptibility to the influence of the extreme thin vs. round body ideals of beauty portrayed by the media

    Acesso a Tratamento Endovascular para Acidente Vascular Cerebral Isquémico em Portugal

    Get PDF
    Introduction: Since the publication of endovascular treatment trials and European Stroke Guidelines, Portugal has re-organized stroke healthcare. The nine centers performing endovascular treatment are not equally distributed within the country, which may lead to differential access to endovascular treatment. Our main aim was to perform a descriptive analysis of the main treatment metrics regarding endovascular treatment in mainland Portugal and its administrative districts. Material and methods: A retrospective national multicentric cohort study was conducted, including all ischemic stroke patients treated with endovascular treatment in mainland Portugal over two years (July 2015 to June 2017). All endovascular treatment centers contributed to an anonymized database. Demographic, stroke-related and procedure-related variables were collected. Crude endovascular treatment rates were calculated per 100 000 inhabitants for mainland Portugal, and each district and endovascular treatment standardized ratios (indirect age-sex standardization) were also calculated. Patient time metrics were computed as the median time between stroke onset, first-door, and puncture. Results: A total of 1625 endovascular treatment procedures were registered. The endovascular treatment rate was 8.27/100 000 inhabitants/year. We found regional heterogeneity in endovascular treatment rates (1.58 to 16.53/100 000/year), with higher rates in districts closer to endovascular treatment centers. When analyzed by district, the median time from stroke onset to puncture ranged from 212 to 432 minutes, reflecting regional heterogeneity. Discussion: Overall endovascular treatment rates and procedural times in Portugal are comparable to other international registries. We found geographic heterogeneity, with lower endovascular treatment rates and longer onset-to-puncture time in southern and inner regions. Conclusion: The overall national rate of EVT in the first two years after the organization of EVT-capable centers is one of the highest among European countries, however, significant regional disparities were documented. Moreover, stroke-onset-to-first-door times and in-hospital procedural times in the EVT centers were comparable to those reported in the randomized controlled trials performed in high-volume tertiary hospitals.info:eu-repo/semantics/publishedVersio

    Integrated sensory motor system in prematurely born children

    Get PDF
    Objetivo: Investigar a existência de sistema sensório motor integrado em recém-nascidos (RNs) prematuros submetidos à estimulação gustativa. Métodos: Estudo experimental analítico e duplo-cego. Participaram 90 RNs prematuros, divididos em dois grupos (água e sacarose para análise (PA) 12%), filmados durante 15 minutos (primeiro e último momentos, sem estimulação; e segundo momento com estimulação gustativa). Três juízes independentes analisaram os comportamentos mão na boca direita e esquerda e sucção da mão direita e esquerda durante os diversos estados comportamentais, inseridos no banco de dados do Statistical Package for Social Science, sendo considerados em concordância os eventos observados por pelo menos dois deles. Empregou-se teste de correlação de Spearman com nível de significância valor de p<0,05. Resultados: Tanto ao serem considerados os grupos separadamente quanto juntos, mão na boca direita e esquerda tiveram inicialmente correlação moderada, sendo que mão na boca direita manteve-se forte no final e mão na boca esquerda finalizou com correlação moderada e forte, de acordo com cada estado comportamental. Sucção de mão direita na totalidade e em sacarose apresentou-se inicialmente com correlação forte no estado sonolento, passando para moderada ao final. No estado alerta houve inicialmente correlação fraca em ambos os estímulos, finalizando com correlação moderada em sacarose e forte em água. Sucção de mão esquerda apresentou-se inicialmente correlação moderada em alerta, finalizando com correlação fraca no grupo sacarose, o que não ocorreu na água, que iniciou e finalizou forte. Conclusão: A estimulação oral influenciou na coordenação mão-boca, independente do estímulo, evidenciando integração sensório motora precoce, mas não inferindo sobre capacidade de discriminação gustativa nos prematuros. _________________________________________________________________________________________ ABSTRACT: Purpose: To investigate about an integrated sensory motor system existence in premature newborns, submitted to gustatory stimulation. Methods: Analytical and experimental study of contents, double-blind. Being participants 90 premature newborns, divided into two groups (water or sucrose analysis 12%). Recorded by 15 minutes (first and last moments, without stimulation; and second time with gustatory stimulation). Three independent judges analyzed the behaviors in the right hand and left hand in the mouth and suction in the left and right and hand during the various behavioral states, those being inserted in the database of Statistical Package for Social Science, being then considered that the events observed by at least two of them. It was made use of Spearman’s rank correlation test on a significance level by p<0.05. Results: Considering the groups both separately and together, right and left had initially moderate correlation, being right hand in the mouth remained strong at the end and left hand in the mouth finished on moderate and strong correlation, according to each behavioral state. Right hand suction in its total and sucrose showed a strong correlation initially in drowsy state, becoming moderate at the end. In alertness state there was initially a weak correlation in both stimuli ending in moderate correlation in sucrose and strong in water. Left hand suction presented initially moderate correlation on the alert state, ending in weak correlation in sucrose stimuli, which did not occur in the water that started and finished strong. Conclusion: The oral stimulation influenced the hand-mouth coordination, showing early motor sensory integration. However, there was no discrimination about the gustatory capacity on the newborns

    The Werner Syndrome Protein Suppresses Telomeric Instability Caused by Chromium (VI) Induced DNA Replication Stress

    Get PDF
    Telomeres protect the chromosome ends and consist of guanine-rich repeats coated by specialized proteins. Critically short telomeres are associated with disease, aging and cancer. Defects in telomere replication can lead to telomere loss, which can be prevented by telomerase-mediated telomere elongation or activities of the Werner syndrome helicase/exonuclease protein (WRN). Both telomerase and WRN attenuate cytotoxicity induced by the environmental carcinogen hexavalent chromium (Cr(VI)), which promotes replication stress and DNA polymerase arrest. However, it is not known whether Cr(VI)-induced replication stress impacts telomere integrity. Here we report that Cr(VI) exposure of human fibroblasts induced telomeric damage as indicated by phosphorylated H2AX (γH2AX) at telomeric foci. The induced γH2AX foci occurred in S-phase cells, which is indicative of replication fork stalling or collapse. Telomere fluorescence in situ hybridization (FISH) of metaphase chromosomes revealed that Cr(VI) exposure induced an increase in telomere loss and sister chromatid fusions that were rescued by telomerase activity. Human cells depleted for WRN protein exhibited a delayed reduction in telomeric and non-telomeric damage, indicated by γH2AX foci, during recovery from Cr(VI) exposure, consistent with WRN roles in repairing damaged replication forks. Telomere FISH of chromosome spreads revealed that WRN protects against Cr(VI)-induced telomere loss and downstream chromosome fusions, but does not prevent chromosome fusions that retain telomere sequence at the fusion point. Our studies indicate that environmentally induced replication stress leads to telomere loss and aberrations that are suppressed by telomerase-mediated telomere elongation or WRN functions in replication fork restoration
    • …
    corecore