Protective effects of exogenous and endogenous hydrogen sulfide in mast cell-mediated pruritus and cutaneous acute inflammation in mice.

Published onlineJournal ArticleThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The recently described 'gasomediator' hydrogen sulfide (H2S) has been involved in pain mechanisms, but its effect on pruritus, a sensory modality that similarly to pain acts as a protective mechanism, is poorly known and controversial. The effects of the slow-releasing (GYY4137) and spontaneous H2S donors (Na2S and Lawesson's reagent, LR) were evaluated in histamine and compound 48/80 (C48/80)-dependent dorsal skin pruritus and inflammation in male BALB/c mice. Animals were intradermally (i.d.) injected with C48/80 (3μg/site) or histamine (1μmol/site) alone or co-injected with Na2S, LR or GYY4137 (within the 0.3-100nmol range). The involvement of endogenous H2S and KATP channel-dependent mechanism were also evaluated. Pruritus was assessed by the number of scratching bouts, whilst skin inflammation was evaluated by the extravascular accumulation of intravenously injected (125)I-albumin (plasma extravasation) and myeloperoxidase (MPO) activity (neutrophil recruitment). Histamine or C48/80 significantly evoked itching behavior paralleled by plasma extravasation and increased MPO activity. Na2S and LR significantly ameliorated histamine or C48/80-induced pruritus and inflammation, although these effects were less pronounced or absent with GYY4137. Inhibition of endogenous H2S synthesis exacerbated C48/80-induced responses, whereas the blockade of KATP channels by glibenclamide did not. High-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) revealed that Na2S and LR, but not GYY4137, significantly attenuated C48/80-induced histamine release from rat peritoneal mast cell in vitro. We provide first evidences that H2S exerted protective effect against acute pruritus mediated via histaminergic pathways in murine skin, thus making of H2S donors a potential alternative/complementary therapy for treatment of acute pruritus.Sao Paulo Research Foundation (Fapesp grant numbers: 2013/04.151-3, 2014/15.576-8, 2014/24.518-1) and CNPq (grant number: 163278/2012-1). GDN, MNM and SKPC are recipients of fellowships from the National Council for Scientific and Technological Development (CNPq). We thank Irene M Gouvea, Flávia B de Lira and Mauro Sucupira for their techinical support

Genetic diversity of Brazilian isolates of feline immunodeficiency virus

We isolated Feline immunodeficiency virus (FIV) from three adult domestic cats, originating from two open shelters in Brazil. Viruses were isolated from PBMC following co-cultivation with the feline T-lymphoblastoid cell line MYA-1. All amplified env gene products were cloned directly into pGL8MYA. The nucleic acid sequences of seven clones were determined and then compared with those of previously described isolates. The sequences of all of the Brazilian virus clones were distinct and phylogenetic analysis revealed that all belong to subtype B. Three variants isolated from one cat and two variants were isolated from each of the two other cats, indicating that intrahost diversity has the potential to pose problems for the treatment and diagnosis of FIV infection

A linkage map for the B-genome of Arachis (Fabaceae) and its synteny to the A-genome

<p>Abstract</p> <p>Background</p> <p><it>Arachis hypogaea </it>(peanut) is an important crop worldwide, being mostly used for edible oil production, direct consumption and animal feed. Cultivated peanut is an allotetraploid species with two different genome components, A and B. Genetic linkage maps can greatly assist molecular breeding and genomic studies. However, the development of linkage maps for <it>A. hypogaea </it>is difficult because it has very low levels of polymorphism. This can be overcome by the utilization of wild species of <it>Arachis</it>, which present the A- and B-genomes in the diploid state, and show high levels of genetic variability.</p> <p>Results</p> <p>In this work, we constructed a B-genome linkage map, which will complement the previously published map for the A-genome of <it>Arachis</it>, and produced an entire framework for the tetraploid genome. This map is based on an F₂population of 93 individuals obtained from the cross between the diploid <it>A. ipaënsis </it>(K30076) and the closely related <it>A. magna </it>(K30097), the former species being the most probable B genome donor to cultivated peanut. In spite of being classified as different species, the parents showed high crossability and relatively low polymorphism (22.3%), compared to other interspecific crosses. The map has 10 linkage groups, with 149 loci spanning a total map distance of 1,294 cM. The microsatellite markers utilized, developed for other <it>Arachis </it>species, showed high transferability (81.7%). Segregation distortion was 21.5%. This B-genome map was compared to the A-genome map using 51 common markers, revealing a high degree of synteny between both genomes.</p> <p>Conclusion</p> <p>The development of genetic maps for <it>Arachis </it>diploid wild species with A- and B-genomes effectively provides a genetic map for the tetraploid cultivated peanut in two separate diploid components and is a significant advance towards the construction of a transferable reference map for <it>Arachis</it>. Additionally, we were able to identify affinities of some <it>Arachis </it>linkage groups with <it>Medicago truncatula</it>, which will allow the transfer of information from the nearly-complete genome sequences of this model legume to the peanut crop.</p

Inequities in access to mammographic screening in Brazil

Our objectives with this study were to describe the spatial distribution of mammographic screening coverage across small geographical areas (micro-regions) in Brazil, and to analyze whether the observed differences were associated with spatial inequities in socioeconomic conditions, provision of health care, and healthcare services utilization. We performed an area-based ecological study on mammographic screening coverage in the period of 2010-2011 regarding socioeconomic and healthcare variables. The units of analysis were the 438 health micro-regions in Brazil. Spatial regression models were used to study these relationships. There was marked variability in mammographic coverage across micro-regions (median = 21.6%; interquartile range: 8.1%-37.9%). Multivariable analyses identified high household income inequality, low number of radiologists/100,000 inhabitants, low number of mammography machines/10,000 inhabitants, and low number of mammograms performed by each machine as independent correlates of poor mammographic coverage at the micro-region level. There was evidence of strong spatial dependence of these associations, with changes in one micro-region affecting neighboring micro-regions, and also of geographical heterogeneities. There were substantial inequities in access to mammographic screening across micro-regions in Brazil, in 2010-2011, with coverage being higher in those with smaller wealth inequities and better access to health care

Mammographic over-screening: Evaluation based on probabilistic linkage of records databases from the breast cancer information system (SISMAMA)

The Brazilian Ministry of Health recommends biennial mammographic screening for women aged between 50 and 69 years. Since screening is opportunistic in the country, the actual periodicity varies. This study sought to test a methodology for estimating over-screening due to excessive periodicity, defined as a smaller than recommended interval between exams, and its association with socio-demographic characteristics. A cohort of women who underwent mammography in 2010, and whose result was normal, was assembled through probabilistic linkage SISMAMA records based on a set of personal identifiers. We used data from women living in the micro health region of Juiz de Fora/Lima Duarte/Bom Jardim, Minas Gerais State, Brazil, who were followed in the System until the end of 2012. The rate of over-screening was 150/1,000 women/year (95%CI: 144.9-155.9), affecting 21% of women. Over-screening increased by 24% during Pink October campaigns (adjusted HR = 1.24; 95%CI: 1.15-1.35). The shorter the time passed since the last mammogram, the greater the odds of over-screening. Compared with women who had never had a mammogram prior to 2010, women who had had one in the previous 2 years were two times more likely to be over-screened (adjusted HR = 2.01; 95%CI: 1.74-2.31) whilst those who had had a mammogram ≤ 1 year previously were three times more likely to be over-screened (adjusted HR = 3.27; 95%CI: 2.87-3.73). Over-screening was substantial in this population, excessively exposing women to the risks of screening with no additional benefits and overestimating mammogram coverage. The methodology proved to be successful and should be applied to representative populations in order to guide breast cancer control policies