919 research outputs found
Functional characterization of 8-oxoguanine DNA glycosylase of Trypanosoma cruzi
The oxidative lesion 8-oxoguanine (8-oxoG) is removed during base excision repair by the 8-oxoguanine DNA glycosylase 1 (Ogg1). This lesion can erroneously pair with adenine, and the excision of this damaged base by Ogg1 enables the insertion of a guanine and prevents DNA mutation. In this report, we identified and characterized Ogg1 from the protozoan parasite Trypanosoma cruzi (TcOgg1), the causative agent of Chagas disease. Like most living organisms, T. cruzi is susceptible to oxidative stress, hence DNA repair is essential for its survival and improvement of infection. We verified that the TcOGG1 gene encodes an 8-oxoG DNA glycosylase by complementing an Ogg1-defective Saccharomyces cerevisiae strain. Heterologous expression of TcOGG1 reestablished the mutation frequency of the yeast mutant ogg1-/- (CD138) to wild type levels. We also demonstrate that the overexpression of TcOGG1 increases T. cruzi sensitivity to hydrogen peroxide (H2O2). Analysis of DNA lesions using quantitative PCR suggests that the increased susceptibility to H2O2 of TcOGG1-overexpressor could be a consequence of uncoupled BER in abasic sites and/or strand breaks generated after TcOgg1 removes 8-oxoG, which are not rapidly repaired by the subsequent BER enzymes. This hypothesis is supported by the observation that TcOGG1-overexpressors have reduced levels of 8-oxoG both in the nucleus and in the parasite mitochondrion. The localization of TcOgg1 was examined in parasite transfected with a TcOgg1-GFP fusion, which confirmed that this enzyme is in both organelles. Taken together, our data indicate that T. cruzi has a functional Ogg1 ortholog that participates in nuclear and mitochondrial BER. © 2012 Furtado et al
Variations of training load, monotony, and strain and dose-response relationships with maximal aerobic speed, maximal oxygen uptake, and isokinetic strength in professional soccer players
This study aimed to identify variations in weekly training load, training monotony, and training strain across a 10-week period (during both, pre- and in-season phases); and to analyze the dose-response relationships between training markers and maximal aerobic speed (MAS), maximal oxygen uptake, and isokinetic strength. Twenty-seven professional soccer players (24.9±3.5 years old) were monitored across the 10-week period using global positioning system units. Players were also tested for maximal aerobic speed, maximal oxygen uptake, and isokinetic strength before and after 10 weeks of training. Large positive correlations were found between sum of training load and extension peak torque in the right lower limb (r = 0.57, 90%CI[0.15;0.82]) and the ratio agonist/antagonist in the right lower limb (r = 0.51, [0.06;0.78]). It was observed that loading measures fluctuated across the period of the study and that the load was meaningfully associated with changes in the fitness status of players. However, those magnitudes of correlations were small-to-large, suggesting that variations in fitness level cannot be exclusively explained by the accumulated load and loading profile
Radiative contribution to neutrino masses and mixing in SSM
In an extension of the minimal supersymmetric standard model (popularly known
as the SSM), three right handed neutrino superfields are introduced to
solve the -problem and to accommodate the non-vanishing neutrino masses
and mixing. Neutrino masses at the tree level are generated through parity
violation and seesaw mechanism. We have analyzed the full effect of one-loop
contributions to the neutrino mass matrix. We show that the current three
flavour global neutrino data can be accommodated in the SSM, for both
the tree level and one-loop corrected analyses. We find that it is relatively
easier to accommodate the normal hierarchical mass pattern compared to the
inverted hierarchical or quasi-degenerate case, when one-loop corrections are
included.Comment: 51 pages, 14 figures (58 .eps files), expanded introduction, other
minor changes, references adde
TRY plant trait database - enhanced coverage and open access
Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
Classificação do atendimento pré-hospitalar pediátrico como instrumento para otimizar a alocação de recursos no atendimento do trauma na cidade de São Paulo, Brasil
PURPOSE: To evaluate the pediatric prehospital care in São Paulo, the databases from basic life support units (BLSU) and ALSU, and to propose a simple and effective method for evaluating trauma severity in children at the prehospital phase. METHODS: A single firemen headquarter coordinates all prehospital trauma care in São Paulo city. Two databases were analyzed for children from 0 to 18 years old between 1998 and 2001: one from the Basic Life Support Units (BLSU - firemen) and one from the Advanced Life Support Units (ALSU - doctor and firemen). During this period, advanced life support units provided medical reports from 604 victims, while firemen provided 12.761 reports (BLSU+ALSU). Pre-Hospital Pediatric Trauma Classification is based on physiological status, trauma mechanism and anatomic injuries suggesting high energy transfer. In order to evaluate the proposed classification, it was compared to the Glasgow Coma Score and to the Revised Trauma Score. RESULTS: There was a male predominance in both databases and the most common trauma mechanism was transport related, followed by falls. Mortality was 1.6% in basic life support units and 9.6% in ALSU. There was association among the proposed score, the Glasgow Coma Score and to the Revised Trauma Score (p<0.0001). CONCLUSION: Pre-Hospital Pediatric Trauma Classification is a simple and reliable method for assessment, triage and recruitment of pediatric trauma resources.OBJETIVO: Avaliar o atendimento pré-hospitalar de crianças e adolescentes em São Paulo, avaliar o banco de dados das Unidades de Suporte Básico (UR) e Avançado (USA) e propor um método simples e eficaz para a avaliação da gravidade do trauma pediátrico na fase pré-hospitalar. MÉTODOS: Uma única central do Corpo de Bombeiros (COBOM) coordena todo o atendimento pré-hospitalar em São Paulo. Dois bancos de dados foram analisados para crianças de 0 a 18 anos de idade, entre 1998 e 2001: um das Unidades de Suporte Básico de Vida (UR- bombeiros) e outra de Unidades de Suporte Avançado (USA - médico e bombeiros). Neste período, o Serviço de Atendimento Médico de Urgência do Estado de São Paulo (SAMU) forneceu relatórios médicos de 604 vítimas, enquanto os bombeiros forneceram relatórios de 12.761 vitimas (UR+USA). A classificação do trauma pré-hospitalar pediátrico é baseada na condição fisiológica, mecanismo de trauma e lesões anatômicas das vítimas. A classificação do trauma pré-hospitalar pediátrico foi comparada à Escala de Coma de Glasgow (GCS) e ao Escore de Trauma Revisado (RTS). RESULTADOS: Houve predominância do sexo masculino em ambos bancos de dados. O mecanismo de trauma mais freqüente foi relacionado a transporte, seguido de quedas. A mortalidade foi 1,6% nas Unidades Básicas e 9,6% no Suporte Avançado. Houve associação entre a classificação do trauma pré-hospitalar pediátrico, Escala de Coma de Glasgow (GCS) e ao Escore de Trauma Revisado (RTS) GCS e RTS (p<0,0001). CONCLUSÃO: A classificação do trauma pré-hospitalar pediátrico é um método simples e confiável para a avaliação, triagem e recrutamento de recursos para o atendimento pré-hospitalar do trauma pediátrico.Universidade Federal de São Paulo (UNIFESP) Department of SurgeryUNIFESP, Department of SurgerySciEL
BPI-fold (BPIF) containing/plunc protein expression in human fetal major and minor salivary glands.
The aim of this study was to determine expression, not previously described, of PLUNC (palate, lung, and nasal epithelium clone) (BPI-fold containing) proteins in major and minor salivary glands from very early fetal tissue to the end of the second trimester and thus gain further insight into the function of these proteins. Early fetal heads, and major and minor salivary glands were collected retrospectively and glands were classified according to morphodifferentiation stage. Expression of BPI-fold containing proteins was localized through immunohistochemistry. BPIFA2, the major BPI-fold containing protein in adult salivary glands, was detected only in the laryngeal pharynx; the lack of staining in salivary glands suggested salivary expression is either very late in development or is only in adult tissues. Early expression of BPIFA1 was seen in the trachea and nasal cavity with salivary gland expression only seen in late morphodifferentiation stages. BPIFB1 was seen in early neural tissue and at later stages in submandibular and sublingual glands. BPIFA1 is significantly expressed in early fetal oral tissue but BPIFB1 has extremely limited expression and the major salivary BPIF protein (BPIFA2) is not produced in fetal development. Further studies, with more sensitive techniques, will confirm the expression pattern and enable a better understanding of embryonic BPIF protein function
Coadministration of the Three Antigenic Leishmania infantum Poly (A) Binding Proteins as a DNA Vaccine Induces Protection against Leishmania major Infection in BALB/c Mice
Highly conserved intracellular proteins from Leishmania have been described as antigens in natural and experimental infected mammals. The present study aimed to evaluate the antigenicity and prophylactic properties of the Leishmania infantum Poly (A) binding proteins (LiPABPs). Three different members of the LiPABP family have been described. Recombinant tools based on these proteins were constructed: recombinant proteins and DNA vaccines. The three recombinant proteins were employed for coating ELISA plates. Sera from human and canine patients of visceral leishmaniasis and human patients of mucosal leishmaniasis recognized the three LiPABPs. In addition, the protective efficacy of a DNA vaccine based on the combination of the three Leishmania PABPs has been tested in a model of progressive murine leishmaniasis: BALB/c mice infected with Leishmania major. The induction of a Th1-like response against the LiPABP family by genetic vaccination was able to down-regulate the IL-10 predominant responses elicited by parasite LiPABPs after infection in this murine model. This modulation resulted in a partial protection against L. major infection. LiPABP vaccinated mice showed a reduction on the pathology that was accompanied by a decrease in parasite burdens, in antibody titers against Leishmania antigens and in the IL-4 and IL-10 parasite-specific mediated responses in comparison to control mice groups immunized with saline or with the non-recombinant plasmid. The results presented here demonstrate for the first time the prophylactic properties of a new family of Leishmania antigenic intracellular proteins, the LiPABPs. The redirection of the immune response elicited against the LiPABP family (from IL-10 towards IFN-γ mediated responses) by genetic vaccination was able to induce a partial protection against the development of the disease in a highly susceptible murine model of leishmaniasisThe study was supported in Spain by grants from Ministerio de Ciencia e Innovación FIS
PI11/00095 and FISPI14/00366 from the Instituto de Salud Carlos III within the Network of TropicalDiseases Research (VI P I+D+I 2008-2011, ISCIII -Subdirección General de Redes y Centros de Investigación Cooperativa (RD12/0018/0009)). This work was also supported in Brazil by a grant from CNPq (Ciencia sem Fronteiras-PVE 300174/2014-4). A CBMSO institutional grant from Fundación Ramón Areces is also acknowledged. EAFC is a grant recipient of CNPq. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip
Triggering of the 2014 M_w7.3 Papanoa earthquake by a slow slip event in Guerrero, Mexico
Since their discovery two decades ago, slow slip events have been shown to play an important role in accommodating strain in subduction zones. However, the physical mechanisms that generate slow slip and the relationships with earthquakes are unclear. Slow slip events have been recorded in the Guerrero segment of the Cocos–North America subduction zone. Here we use inversion of position time series recorded by a continuous GPS network to reconstruct the evolution of aseismic slip on the subduction interface of the Guerrero segment. We find that a slow slip event began in February 2014, two months before the magnitude (M_w) 7.3 Papanoa earthquake on 18 April. The slow slip event initiated in a region adjacent to the earthquake hypocentre and extended into the vicinity of the seismogenic zone. This spatio-temporal proximity strongly suggests that the Papanoa earthquake was triggered by the ongoing slow slip event. We demonstrate that the triggering mechanism could be either static stress increases in the hypocentral region, as revealed by Coulomb stress modelling, or enhanced weakening of the earthquake hypocentral area by the slow slip. We also show that the plate interface in the Guerrero area is highly coupled between slow slip events, and that most of the accumulated strain is released aseismically during the slow slip episodes
Application of Multi-SNP Approaches Bayesian LASSO and AUC-RF to Detect Main Effects of Inflammatory-Gene Variants Associated with Bladder Cancer Risk
The relationship between inflammation and cancer is well established in several tumor types, including bladder cancer. We
performed an association study between 886 inflammatory-gene variants and bladder cancer risk in 1,047 cases and 988
controls from the Spanish Bladder Cancer (SBC)/EPICURO Study. A preliminary exploration with the widely used univariate
logistic regression approach did not identify any significant SNP after correcting for multiple testing. We further applied two
more comprehensive methods to capture the complexity of bladder cancer genetic susceptibility: Bayesian Threshold
LASSO (BTL), a regularized regression method, and AUC-Random Forest, a machine-learning algorithm. Both approaches
explore the joint effect of markers. BTL analysis identified a signature of 37 SNPs in 34 genes showing an association with
bladder cancer. AUC-RF detected an optimal predictive subset of 56 SNPs. 13 SNPs were identified by both methods in the
total population. Using resources from the Texas Bladder Cancer study we were able to replicate 30% of the SNPs assessed.
The associations between inflammatory SNPs and bladder cancer were reexamined among non-smokers to eliminate the
effect of tobacco, one of the strongest and most prevalent environmental risk factor for this tumor. A 9 SNP-signature was
detected by BTL. Here we report, for the first time, a set of SNP in inflammatory genes jointly associated with bladder cancer
risk. These results highlight the importance of the complex structure of genetic susceptibility associated with cancer risk.The work was partially supported by the Fondo de Investigacion Sanitaria, Instituto de Salud Carlos III (G03/174, 00/0745, PI051436, PI061614, PI09-02102, G03/174 and Sara Borrell fellowship to ELM) and Ministry of Science and Innovation (MTM2008-06747-C02-02 and FPU fellowship award to VU), Spain; AGAUR-Generalitat de Catalunya (Grant 2009SGR-581); Fundaciola Maratode TV3; Red Tematica de Investigacion Cooperativa en Cancer (RTICC); Asociacion Espanola Contra el Cancer (AECC); EU-FP7-201663; and RO1-CA089715 and CA34627; the Spanish National Institute for Bioinformatics (www.inab.org); and by the Intramural Research Program of the Division of Cancer Epidemiology and Genetics, National Cancer Institute, USA. MD Anderson support for this project included U01 CA 127615 (XW); R01 CA 74880 (XW); P50 CA 91846 (XW, CPD); Betty B. Marcus Chair fund in Cancer Prevention (XW); UT Research Trust fund (XW) and R01 CA 131335 (JG)
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