747 research outputs found
The Effect of Fire Smoke Exposure on Firefighters' Lung Function: A Meta-Analysis
Firefighters are exposed to a range of harmful substances during firefighting. Exposure to fire smoke has been associated with a decrease in their lung function. However, the cause-effect relationship between those two factors is not yet demonstrated. This meta-analysis aimed to evaluate the potential associations between firefighters' occupational exposure and their lung function deterioration. Studies were identified from PubMed, Web of Science, Scopus and Science Direct databases (August 1990-March 2021). The studies were included when reporting the lung function values of Forced Expiratory Volume in 1 s (FEV1) or Forced Vital Capacity (FVC). The meta-analyses were performed using the generic inverse variance in R software with a random-effects model. Subgroup analysis was used to determine if the lung function was influenced by a potential study effect or by the participants' characteristics. A total of 5562 participants from 24 studies were included. No significant difference was found between firefighters' predicted FEV1 from wildland, 97.64% (95% CI: 91.45-103.82%; I-2 = 99%), and urban fires, 99.71% (95% CI: 96.75-102.67%; I-2 = 98%). Similar results were found for the predicted FVC. Nevertheless, the mean values of firefighters' predicted lung function varied significantly among studies, suggesting many confounders, such as trials' design, statistical methods, methodologies applied, firefighters' daily exposure and career length, hindering an appropriate comparison between the studies
Avaliação do potencial citotóxico de microplásticos em linhas celulares intestinais, hepáticas e neuronais
Os Microplásticos (MPs) são uma classe emergente de contaminantes, que resultam da libertação directa de pequenas partÃculas que constituem total ou parcialmente objetos de uso quotidiano ou da deterioração de plásticos que originalmente possuem maiores dimensões. O polietileno (PE), a poliamida (PA-nylon 12) e o policloreto de vinilo (PVC) são três polÃmeros muito comumente utilizados no fabrico de sacos de plástico, recipientes e utensÃlios domésticos, produtos de higiene pessoal, componentes automóveis e de eletrónica e materiais de construção. Devido à sua ubiquidade (resultante da extensa utilização), os seres vivos estão constantemente expostos a estes contaminantes. No caso humano, a ingestão diária de microplásticos é uma das formas mais frequentes de exposição, tornando assim fundamental avaliar a sua potencial toxicidade. Neste trabalho a citotoxicidade de PE, PA-nylon 12 e PVC foram avaliadas em três linhas celulares distintas: células do intestino (Caco-2), do fÃgado (HepG2) e neurónios (N27). De uma forma geral, os microplásticos testados apresentaram toxicidade para as linhas celulares N27 e HepG2, com exceção do PE nesta última. Por outro lado, para as células Caco-2 não foram registadas reduções significativas na viabilidade celular
Motivations and barriers to prosthesis users participation in physical activity, exercise and sport : a review of the literature
The UK will host the Paralympics in 2012 and the Commonwealth Games in 2014 showcasing the talents of elite athletes and aiming to inspire the population to become involved. However, low levels of physical activity (PA) are prevalent: only 40% of men and 28% of women meet the minimum UK recommendations. The limb absent population is no exception. To determine if people with limb amputations are participating in physical activity and sport; whether post-amputation activity levels match pre-amputation levels; and if there are motivations and barriers to participation. Study design: Literature review Five reviewers systematically search of peer reviewed and gray literature in seven bibliographic databases and the Cochrane Library. Results: Following rigorous elimination, 12 articles were finally included in the review and critically appraised. Four themes were identified: components, rehabilitation outcomes, body image and motivations and barriers to participation. People with limb absence are not participating in PA conducive to health benefits, and only a minority participate in exercise and sports. Participation following amputation does not mirror that of pre-amputation levels, and more barriers than motivations exist to adopting and maintaining a physically active lifestyle. This literature review aims to inform those involved in rehabilitation and ongoing care of those with limb absence about what motivates or precludes their participation in physical activity, exercise and sport. Such knowledge could be applied to improving health and well being in this population
Effects of bromopride on the healing of left colon anastomoses of rats
Objetivo: Avaliar os efeitos da bromoprida sobre a formação de aderências e a cicatrização de anastomoses de cólon esquerdo de
ratos. Métodos: Foram incluÃdos 40 ratos, divididos em dois grupos contendo 20 animais, para administração de bromoprida (grupo
de estudo- E) ou solução fisiológica (grupo controle- C). Cada grupo foi dividido em subgrupos contendo 10 animais cada, para
eutanásia no terceiro (E3 e C3) ou no sétimo dia (E7 e C7) de pós-operatório. Os ratos foram submetidos à secção do cólon esquerdo
e anastomose término-terminal. No dia da relaparotomia, foi avaliada a quantidade total de aderências e removido um segmento
colônico contendo a anastomose para análise histopatológica, da força de ruptura e da concentração de hidroxiprolina. Resultados:
Não houve diferença entre os grupos em relação à evolução clÃnica. Dois animais do grupo de estudo apresentaram deiscência
de anastomose bloqueada. Os animais que receberam bromoprida apresentaram número de aderências intracavitárias e aderências
à anastomose semelhantes ao grupo controle. As anastomoses dos animais do grupo E3 apresentaram menor resistência de ruptura
do que as do grupo C3 (p=0,04). Este efeito não ocorreu no sétimo dia de pós-operatório (p=0,37). Não houve diferença significativa
entre os grupos em relação à histopatologia ou concentração de hidroxiprolina das anastomoses. Conclusão: O uso da bromoprida
está associado à diminuição da resistência tênsil de anastomoses do cólon esquerdo de ratos no terceiro dia de pós-operatório.Objective: To evaluate the effects of bromopride on the formation of adhesions and anastomotic healing in the left colon of rats.
Methods: We divided 40 rats into two groups of 20 animals, administration of bromopride (study group-E) or saline (control group-
C). Each group was divided into subgroups containing 10 animals each for euthanasia in the third (C3 and E3) or the seventh (E7 and
C7) postoperative days. The rats were submitted to section of the left colon and end-to-end anastomosis. On the day of reoperation,
we evaluated the total amount of adhesions and removed a colonic segment containing the anastomosis for histopathological
analysis, assessment of rupture strength and hydroxyproline concentration. Results: There was no difference between groups in
relation to clinical outcome. Two animals in the study group had blocked anastomotic leakage. The animals that received bromopride
had the number of intracavitary adhesions and adhesions to the anastomosis similar to the control group. The anastomoses from the
group E3 animals showed lower resistance to rupture the one from the C3 group (p = 0.04). This effect did not occur on the seventh
postoperative day (p = 0.37). There was no significant difference between groups in relation to histopathology and hydroxyproline
concentration in the anastomoses. Conclusion: The use of bromopride was associated with decreased tensile strength of left colon
anastomosis in rats in the third postoperative day
Risk factors for incomplete vaccination and missed opportunity for immunization in rural Mozambique
<p>Abstract</p> <p>Background</p> <p>Inadequate levels of immunization against childhood diseases remain a significant public health problem in resource-poor areas of the globe. Nonetheless, the reasons for incomplete vaccination and non-uptake of immunization services are poorly understood. This study aimed at finding out the reasons for non-vaccination and the magnitude of missed opportunities for vaccination in children less than two years of age in a rural area in southern Mozambique.</p> <p>Methods</p> <p>Mothers of children under two years of age (N = 668) were interviewed in a cross-sectional study. The Road-to-Health card was utilized to check for completeness and correctness of vaccination schedule as well as for identifying the appropriate use of all available opportunities for vaccination. The chi-square test and the logistic regression were used for statistical analysis.</p> <p>Results</p> <p>We found that 28.2% of the children had not completed the vaccination program by two years of age, 25.7% had experienced a missed opportunity for vaccination and 14.9% were incorrectly vaccinated. Reasons for incomplete vaccination were associated with accessibility to the vaccination sites, no schooling of mothers and children born at home or outside Mozambique.</p> <p>Conclusion</p> <p>Efforts to increase vaccination coverage should take into account factors that contribute to the incomplete vaccination status of children. Missed opportunities for vaccination and incorrect vaccination need to be avoided in order to increase the vaccine coverage for those clients that reach the health facility, specially in those countries where health services do not have 100% of coverage.</p
The Endogenous Th17 Response in NO<inf>2</inf>-Promoted Allergic Airway Disease Is Dispensable for Airway Hyperresponsiveness and Distinct from Th17 Adoptive Transfer
Severe, glucocorticoid-resistant asthma comprises 5-7% of patients with asthma. IL-17 is a biomarker of severe asthma, and the adoptive transfer of Th17 cells in mice is sufficient to induce glucocorticoid-resistant allergic airway disease. Nitrogen dioxide (NO2) is an environmental toxin that correlates with asthma severity, exacerbation, and risk of adverse outcomes. Mice that are allergically sensitized to the antigen ovalbumin by exposure to NO2 exhibit a mixed Th2/Th17 adaptive immune response and eosinophil and neutrophil recruitment to the airway following antigen challenge, a phenotype reminiscent of severe clinical asthma. Because IL-1 receptor (IL-1R) signaling is critical in the generation of the Th17 response in vivo, we hypothesized that the IL-1R/Th17 axis contributes to pulmonary inflammation and airway hyperresponsiveness (AHR) in NO2-promoted allergic airway disease and manifests in glucocorticoid-resistant cytokine production. IL-17A neutralization at the time of antigen challenge or genetic deficiency in IL-1R resulted in decreased neutrophil recruitment to the airway following antigen challenge but did not protect against the development of AHR. Instead, IL-1R-/- mice developed exacerbated AHR compared to WT mice. Lung cells from NO2-allergically inflamed mice that were treated in vitro with dexamethasone (Dex) during antigen restimulation exhibited reduced Th17 cytokine production, whereas Th17 cytokine production by lung cells from recipient mice of in vitro Th17-polarized OTII T-cells was resistant to Dex. These results demonstrate that the IL-1R/Th17 axis does not contribute to AHR development in NO2-promoted allergic airway disease, that Th17 adoptive transfer does not necessarily reflect an endogenously-generated Th17 response, and that functions of Th17 responses are contingent on the experimental conditions in which they are generated. © 2013 Martin et al
Evaluation of the role of glutathione in the lead-induced toxicity in Saccharomyces cerevisiae
The effect of intracellular reduced glutathione (GSH) in the lead stress response of Saccharomyces cerevisiae was investigated. Yeast cells exposed to Pb, for 3 h, lost the cell proliferation capacity (viability) and decreased intracellular GSH level. The Pb-induced loss of cell viability was compared among yeast cells deficient in GSH1 (∆gsh1) or GSH2 (∆gsh2) genes and wild-type (WT) cells. When exposed to Pb, ∆gsh1 and ∆gsh2 cells did not display an increased loss of viability, compared with WT cells. However, the depletion of cellular thiols, including GSH, by treatment of WT cells with iodoacetamide (an alkylating agent, which binds covalently to thiol group), increased the loss of viability in Pb-treated cells. In contrast, GSH enrichment, due to the incubation of WT cells with amino acids mixture constituting GSH (l-glutamic acid, l-cysteine and glycine), reduced the Pb-induced loss of proliferation capacity. The obtained results suggest that intracellular GSH is involved in the defence against the Pb-induced toxicity; however, at physiological concentration, GSH seems not to be sufficient to prevent the Pb-induced loss of cell viability
Temporal variance of disturbance did not affect diversity and structure of a marine fouling community in north-eastern New Zealand
Natural heterogeneity in ecological parameters, like population abundance, is more widely recognized and investigated than variability in the processes that control these parameters. Experimental ecologists have focused mainly on the mean intensity of predictor variables and have largely ignored the potential to manipulate variances in processes, which can be considered explicitly in experimental designs to explore variation in causal mechanisms. In the present study, the effect of the temporal variance of disturbance on the diversity of marine assemblages was tested in a field experiment replicated at two sites on the northeast coast of New Zealand. Fouling communities grown on artificial settlement substrata experienced disturbance regimes that differed in their inherent levels of temporal variability and timing of disturbance events, while disturbance intensity was identical across all levels. Additionally, undisturbed assemblages were used as controls. After 150 days of experimental duration, the assemblages were then compared with regard to their species richness, abundance and structure. The disturbance effectively reduced the average total cover of the assemblages, but no consistent effect of variability in the disturbance regime on the assemblages was detected. The results of this study were corroborated by the outcomes from simultaneous replicate experiments carried out in each of eight different biogeographical regions around the world
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