Complement system activation contributes to the ependymal damage induced by microbial neuraminidase

Background In the rat brain, a single intracerebroventricular injection of neuraminidase from Clostridium perfringens induces ependymal detachment and death. This injury occurs before the infiltration of inflammatory blood cells; some reports implicate the complement system as a cause of these injuries. Here, we set out to test the role of complement. Methods The assembly of the complement membrane attack complex on the ependymal epithelium of rats injected with neuraminidase was analyzed by immunohistochemistry. Complement activation, triggered by neuraminidase, and the participation of different activation pathways were analyzed by Western blot. In vitro studies used primary cultures of ependymal cells and explants of the septal ventricular wall. In these models, ependymal cells were exposed to neuraminidase in the presence or absence of complement, and their viability was assessed by observing beating of cilia or by trypan blue staining. The role of complement in ependymal damage induced by neuraminidase was analyzed in vivo in two rat models of complement blockade: systemic inhibition of C5 by using a function blocking antibody and testing in C6-deficient rats. Results The complement membrane attack complex immunolocalized on the ependymal surface in rats injected intracerebroventricularly with neuraminidase. C3 activation fragments were found in serum and cerebrospinal fluid of rats treated with neuraminidase, suggesting that neuraminidase itself activates complement. In ventricular wall explants and isolated ependymal cells, treatment with neuraminidase alone induced ependymal cell death; however, the addition of complement caused increased cell death and disorganization of the ependymal epithelium. In rats treated with anti-C5 and in C6-deficient rats, intracerebroventricular injection of neuraminidase provoked reduced ependymal alterations compared to non-treated or control rats. Immunohistochemistry confirmed the absence of membrane attack complex on the ependymal surfaces of neuraminidase-exposed rats treated with anti-C5 or deficient in C6. Conclusions These results demonstrate that the complement system contributes to ependymal damage and death caused by neuraminidase. However, neuraminidase alone can induce moderate ependymal damage without the aid of complement

Incidence and prevalence of patellofemoral pain: a systematic review and meta-analysis

Background: Patellofemoral pain is considered one of the most common forms of knee pain, affecting adults, adolescents, and physically active populations. Inconsistencies in reported incidence and prevalence exist and in relation to the allocation of healthcare and research funding, there is a clear need to accurately understand the epidemiology of patellofemoral pain. Methods: An electronic database search was conducted, as well as grey literature databases, from inception to June 2017. Two authors independently selected studies, extracted data and appraised methodological quality. If heterogeneous, data were analysed descriptively. Where studies were homogeneous, data were pooled through a meta-analysis. Results: 23 studies were included. Annual prevalence for patellofemoral pain in the general population was reported as 22.7%, and adolescents as 28.9%. Incidence rates in military recruits ranged from 9.7 – 571.4/1,000 person-years, amateur runners in the general population at 1080.5/1,000 person-years and adolescents amateur athletes 5.1% - 14.9% over 1 season. One study reported point prevalence within military populations as 13.5%. The pooled estimate for point prevalence in adolescents was 7.2% (95% Confidence Interval: 6.3% - 8.3%), and in female only adolescent athletes was 22.7% (95% Confidence Interval 17.4% - 28.0%). Conclusion: This review demonstrates high incidence and prevalence levels for patellofemoral pain. Within the context of this, and poor long term prognosis and high disability levels, PFP should be an urgent research priority

Avaliação dos padrões de uso de álcool em usuários de serviços de Atenção Primária à Saúde de Juiz de Fora e Rio Pomba (MG) Evaluation of the patterns of alcohol consumption at Primary Health Care services in Juiz de Fora and Rio Pomba (MG)

Uma parte significativa da população brasileira apresenta padrões de consumo de álcool associados a alto risco de desenvolvimento de problemas. Por tal razão, é fundamental avaliá-los na população para traçar estratégias de prevenção primária e secundária ao seu uso. O objetivo deste estudo foi avaliar esse padrão de consumo dos usuários de serviços da Atenção Primária à Saúde das cidades de Juiz de Fora e Rio Pomba, Minas Gerais. Foi aplicado um instrumento de rastreamento -o AUDIT- a 921 sujeitos recrutados durante as consultas de rotina. Considerando os dados em conjunto, 18,3% das pessoas avaliadas encontravam-se na faixa de uso de risco, 77,9% da amostra faziam uso de baixo risco ou eram abstêmios, e 3,8% pontuaram na faixa sugestiva de dependência. De modo geral, os homens apresentaram comportamento de risco em maior freqüência do que as mulheres, sendo mais prevalente na faixa etária dos 38 aos 47 anos de idade.<br>A significant part of the Brazilian population presents alcohol consumption patterns associated with high risk of development problems. Therefore, it is fundamental to verify the patterns of alcohol consumption among the population in order to outline primary and secondary prevention strategies. The aim of this study is to verify the patterns of alcohol consumption among the users of Primary Health Care in the cities of Juiz de Fora and Rio Pomba, in the state of Minas Gerais. We applied a screening test -the AUDIT- in a sample of 921 people selected during routine consultations. Considering data as a whole, 18.3% of the evaluated people were at the risk use zone; 77.9% had low hazardous alcohol use or were abstemious and 3.8% pointed toward the suggestive dependence zone. In general, men more frequently demonstrated hazardous behavior compared to women, which was also more prevalent in the 38 to 47 year-old-age group