Infertilidade masculina associada ao uso de finasterida

Finasteride is a potent and specific inhibitor of the 5alpha-reductase enzyme in men. Clinical studies have shown that finasteride 1mg/day is effective for promoting hair growth in men with male pattern hair loss. However, there is a concern about the use of finasteride, especially in young fertile patients, because of its action on testosterone metabolism. This paper describes 3 cases of young patients who had very poor seminal quality during finasteride treatment (1 mg/day), and their seminal quality greatly improved after cessation of finasteride treatment. Two of them presented with a left varicocele and the other was obese. We hypothesize that finasteride may not dramatically change the spermatogenesis process in healthy men, but in patients with conditions related to infertility, an amplification of the negative influence of finasteride could occur. Future studies should be done to clarify the extent of the effect of finasteride in patients fertility problems.A finasterida é um potente e específico inibidor da enzima 5alfa-redutase em homens. Estudos clínicos demonstraram que finasterida 1mg/dia diminui a progressão da queda e aumenta o crescimento do cabelo em homens que sofrem de queda de cabelo hereditária. Por sua influência no metabolismo dos andrógenos existe uma preocupação a respeito do seu uso, principalmente em pacientes em idade fértil. Neste trabalho são descritos 3 casos de pacientes jovens, que apresentaram piora do espermograma durante o uso continuado de finasterida 1mg revertida após a suspensão do mesmo. Dois deles tinham varicocele unilateral e o terceiro era obeso. Aparentemente o tratamento com finasterida promoveu alteração significativa na qualidade seminal. Pode-se especular que talvez a finasterida por si só não traga alteração para a espermatogênese como reportado por Overstreet et al. (1999), mas que em pacientes de risco com possíveis causas de infertilidade associadas, possa ocorrer a amplificação da influência deletéria da finasterida. Estudos futuros devem ser realizados para esclarecer a influência da finasterida nestes pacientes

Thermodynamics of a class of non-asymptotically flat black holes in Einstein-Maxwell-Dilaton theory

We analyse in detail the thermodynamics in the canonical and grand canonical ensembles of a class of non-asymptotically flat black holes of the Einstein-(anti) Maxwell-(anti) Dilaton theory in 4D with spherical symmetry. We present the first law of thermodynamics, the thermodynamic analysis of the system through the geometrothermodynamics methods, Weinhold, Ruppeiner, Liu-Lu-Luo-Shao and the most common, that made by the specific heat. The geometric methods show a curvature scalar identically zero, which is incompatible with the results of the analysis made by the non null specific heat, which shows that the system is thermodynamically interacting, does not possess extreme case nor phase transition. We also analyse the local and global stability of the thermodynamic system, and obtain a local and global stability for the normal case for 0<\gamma<1 and for other values of \gamma, an unstable system. The solution where \gamma=0 separates the class of locally and globally stable solutions from the unstable ones.Comment: 18 pages, version accepted for publication in General Relativity and Gravitatio

IL-4-secreting CD4+ T cells are crucial to the development of CD8+ T-cell responses against malaria liver stages.

CD4+ T cells are crucial to the development of CD8+ T cell responses against hepatocytes infected with malaria parasites. In the absence of CD4+ T cells, CD8+ T cells initiate a seemingly normal differentiation and proliferation during the first few days after immunization. However, this response fails to develop further and is reduced by more than 90%, compared to that observed in the presence of CD4+ T cells. We report here that interleukin-4 (IL-4) secreted by CD4+ T cells is essential to the full development of this CD8+ T cell response. This is the first demonstration that IL-4 is a mediator of CD4/CD8 cross-talk leading to the development of immunity against an infectious pathogen

Automatic Network Fingerprinting through Single-Node Motifs

Complex networks have been characterised by their specific connectivity patterns (network motifs), but their building blocks can also be identified and described by node-motifs---a combination of local network features. One technique to identify single node-motifs has been presented by Costa et al. (L. D. F. Costa, F. A. Rodrigues, C. C. Hilgetag, and M. Kaiser, Europhys. Lett., 87, 1, 2009). Here, we first suggest improvements to the method including how its parameters can be determined automatically. Such automatic routines make high-throughput studies of many networks feasible. Second, the new routines are validated in different network-series. Third, we provide an example of how the method can be used to analyse network time-series. In conclusion, we provide a robust method for systematically discovering and classifying characteristic nodes of a network. In contrast to classical motif analysis, our approach can identify individual components (here: nodes) that are specific to a network. Such special nodes, as hubs before, might be found to play critical roles in real-world networks.Comment: 16 pages (4 figures) plus supporting information 8 pages (5 figures

Effects of collagen membranes enriched with in vitro-differentiated N1E-115 cells on rat sciatic nerve regeneration after end-to-end repair

Peripheral nerves possess the capacity of self-regeneration after traumatic injury but the extent of regeneration is often poor and may benefit from exogenous factors that enhance growth. The use of cellular systems is a rational approach for delivering neurotrophic factors at the nerve lesion site, and in the present study we investigated the effects of enwrapping the site of end-to-end rat sciatic nerve repair with an equine type III collagen membrane enriched or not with N1E-115 pre-differentiated neural cells. After neurotmesis, the sciatic nerve was repaired by end-to-end suture (End-to-End group), end-to-end suture enwrapped with an equine collagen type III membrane (End-to-EndMemb group); and end-to-end suture enwrapped with an equine collagen type III membrane previously covered with neural cells pre-differentiated in vitro from N1E-115 cells (End-to-EndMembCell group). Along the postoperative, motor and sensory functional recovery was evaluated using extensor postural thrust (EPT), withdrawal reflex latency (WRL) and ankle kinematics. After 20 weeks animals were sacrificed and the repaired sciatic nerves were processed for histological and stereological analysis. Results showed that enwrapment of the rapair site with a collagen membrane, with or without neural cell enrichment, did not lead to any significant improvement in most of functional and stereological predictors of nerve regeneration that we have assessed, with the exception of EPT which recovered significantly better after neural cell enriched membrane employment. It can thus be concluded that this particular type of nerve tissue engineering approach has very limited effects on nerve regeneration after sciatic end-to-end nerve reconstruction in the rat

Environmental Costs of Government-Sponsored Agrarian Settlements in Brazilian Amazonia

Brazil has presided over the most comprehensive agrarian reform frontier colonization program on Earth, in which ~1.2 million settlers have been translocated by successive governments since the 1970's, mostly into forested hinterlands of Brazilian Amazonia. These settlements encompass 5.3% of this ~5 million km2 region, but have contributed with 13.5% of all land conversion into agropastoral land uses. The Brazilian Federal Agrarian Agency (INCRA) has repeatedly claimed that deforestation in these areas largely predates the sanctioned arrival of new settlers. Here, we quantify rates of natural vegetation conversion across 1911 agrarian settlements allocated to 568 Amazonian counties and compare fire incidence and deforestation rates before and after the official occupation of settlements by migrant farmers. The timing and spatial distribution of deforestation and fires in our analysis provides irrefutable chronological and spatially explicit evidence of agropastoral conversion both inside and immediately outside agrarian settlements over the last decade. Deforestation rates are strongly related to local human population density and road access to regional markets. Agrarian settlements consistently accelerated rates of deforestation and fires, compared to neighboring areas outside settlements, but within the same counties. Relocated smallholders allocated to forest areas undoubtedly operate as pivotal agents of deforestation, and most of the forest clearance occurs in the aftermath of government-induced migration