Utilização da metodologia WGCNA na construção de redes gênicas e identificação de mecanismos envolvidos na resposta de vacas à mastite.

Tendo em vista a importância da predição das funções biológicas de genes ainda não caracterizados e da identificação de redes gênicas, esse trabalho teve por objetivo implantar uma metodologia baseada em co-expressão para análise dos dados gerados nos experimentos de microarranjos da Rede Genômica Animal. Nesse trabalho, dados de um experimento com microarranjos da Embrapa Gado de Leite, realizado para se identificar genes e mecanismos biológicos envolvidos na resposta de vacas leiteiras a infecção por microorganismos causadores da mastite foram utilizados

Electron localization and possible phase separation in the absence of a charge density wave in single-phase 1T-VS2_2

We report on a systematic study of the structural, magnetic and transport properties of high-purity 1T-VS$_2$ powder samples prepared under high pressure. The results differ notably from those previously obtained by de-intercalating Li from LiVS$_2$. First, no Charge Density Wave (CDW) is found by transmission electron microscopy down to 94 K. Though, \textit{ab initio} phonon calculations unveil a latent CDW instability driven by an acoustic phonon softening at the wave vector ${\bf q}_{CDW} \approx$ (0.21,0.21,0) previously reported in de-intercalated samples. A further indication of latent lattice instability is given by an anomalous expansion of the V-S bond distance at low temperature. Second, infrared optical absorption and electrical resistivity measurements give evidence of non metallic properties, consistent with the observation of no CDW phase. On the other hand, magnetic susceptibility and NMR data suggest the coexistence of localized moments with metallic carriers, in agreement with \textit{ab initio} band structure calculations. This discrepancy is reconciled by a picture of electron localization induced by disorder or electronic correlations leading to a phase separation of metallic and non-metallic domains in the nm scale. We conclude that 1T-VS$_2$ is at the verge of a CDW transition and suggest that residual electronic doping in Li de-intercalated samples stabilizes a uniform CDW phase with metallic properties.Comment: 22 pages, 10 Figures. Full resolution pictures available at http://journals.aps.org/prb/abstract/10.1103/PhysRevB.89.23512

Commensurate structural modulation in the charge- and orbitally-ordered phase of the quadruple perovskite (NaMn3_3)Mn4_4O12_{12}

By means of synchrotron x-ray and electron diffraction, we studied the structural changes at the charge order transition $T_{CO}$=176 K in the mixed-valence quadruple perovskite (NaMn$_3$)Mn$_4$O$_{12}$. Below $T_{CO}$ we find satellite peaks indicating a commensurate structural modulation with the same propagation vector q =(1/2,0,-1/2) of the CE magnetic order that appears at low temperature, similarly to the case of simple perovskites like La$_{0.5}$Ca$_{0.5}$MnO$_3$. In the present case, the modulated structure together with the observation of a large entropy change at $T_{CO}$ gives evidence of a rare case of full Mn$^{3+}$/Mn$^{4+}$ charge and orbital order consistent with the Goodenough-Kanamori model.Comment: Accepted for publication in Phys. Rev. B Rapid Communication

Identification of mechanisms involved in mastitis response by means of gene network building.

Mastitis, an inflammation of the mammary gland, is the most prevalent and costly production disease in dairy herds worldwide. It is caused generally by bacteria and accounts for a significant decrease in milk production and quality. One promising approach to reduce problems caused by mastitis, in addition to sanitary care, is the selection of animals resistant to disease and the incorporation of this trait into the herds. Therefore, studies to better understand the mechanisms involved in animal response to this disease are essential to the proposition of new advances in area. In this context, the aim of this study was to identify groups of genes involved in cow response to mastitis infection, through gene network building from microarray data. Gene expression data from the GeneChipâ Bovine Genome Array (Affymetrix) hybridization with milk somatic cells samples from Holstein-Zebu crossbreed dairy cows, obtained before (B) and 24 hrs after (A) artificial infection with Staphylococcus agalactiae, were analyzed using a network building methodology based on gene co-expression. We used WGCNA (Weighted Gene Co-expression Analysis), a systems biology method for describing the correlation patterns among genes across microarray samples, that can be used for finding clusters (modules) of highly correlated genes to identify modules of co-expressed genes, which may correspond to functionally related genes. By comparing two networks (between contrasting data sets), conserved and non-conserved modules can be identified. This strategy, named differential network analysis, aims to identify genes groups that are both differentially expressed and differentially connected, and changes in connectivity may correspond to large-scale rewiring, in response to environmental changes and/or physiologic perturbations. Two microarray data sets, B (n=5) and A (n=5), were preprocessed using affy and gcrma R/Bioconductor packages. A filter was applied, which resulted in the use of only those transcripts present in all samples. Gene co-expression networks were identified separately for each group (B and A), by the R/WGCNA package. Gene networks were compared between the two groups, and non-conserved modules were uncovered from a correlation test of the connectivity values. Our analysis identified a total of 17 modules of co-expressed genes, three of them, designed by the colors grey (n=35), blue (n=37) and turquoise (n=192), non-conserved between the groups. Using Blast2GO for enrichment analysis, we find the molecular function Protein Binding overrepresented in all three modules. However, in despite of the same molecular function, each one of the modules showed distinct characteristcs. Genes of grey module (BTG3, CD3E, MBD1, CHIC2, PLXNA3, MOCS3, NEIL1, VPS45, BCL2) were related to apoptosis and antigen recognition. Genes of turquoise module were enriched in inflammation mediators, including known mastitis marker genes (FGL1, GJA1, F2RL1, PTPRF, S100A2, TGFB2). The blue one uncovered genes involved in cell division and inflammatory response (CD97, MAD2L1, ZFP106, CDKN2C, LOC514364, NOP14, PCBD1, LOC100139798, AP1S1, EDN1, IL1B, ANXA11). Our study identified some mechanisms (represented by gene modules) that have changed in cows in early response to mastitis infection. Further analysis are being carried out, based on these results, to advance the understanding of animals response to the disease, which can lead to identify the candidate genes that could be used in breeding programs.X-MEETING 2011

Instrumental profile of MYTHEN detector in Debye-Scherrer geometry

The main aberrations affecting data collected with 1D position sensitive detectors in Debye-Scherrer capillary geometry are examined, and analytical corrections proposed. The equations are implemented in two of the most advanced software based on the Rietveld and Whole Powder Pattern Modelling methods, respectively, for structure and microstructure analysis. Application to MYTHEN, a fast single photon counting detector developed at the Swiss Light Source, is discussed in detai

Kidney Transplantation From Donors with Hepatitis B

The growing demand for organ donors to supply the increasing number of patients on kidney waiting lists has led most transplant centers to develop protocols that allow safe use of organs from donors with special clinical situations previously regarded as contraindications. Deceased donors with previous hepatitis B may be a safe resource to increase the donor pool even if there is still controversy among transplantation centers regarding the use of hepatitis B surface antigen-positive donors for renal transplantation. However, when allocated to serology-matched recipients, kidney transplantation from donors with hepatitis B may result in excellent short-term outcome. Many concerns may arise in the long-term outcome, and studies must address the evaluation of the progression of liver disease and the rate of reactivation of liver disease in the recipients. Accurate selection and matching of both donor and recipient and correct post-transplant management are needed to achieve satisfactory long-term outcomes

Antioxidant dietary deficiency induces caspase activation in chick skeletal muscle cells

Apoptosis and necrosis are two distinct forms of cell death that can occur in response to different agents and stress conditions. In order to verify if the oxidative stress induced by dietary selenium and vitamin E deficiencies can lead muscle cells to apoptosis, one-day-old chicks were reared using diets differing in their vitamin E (0 or 10 IU/kg) and selenium (0 or 0.15 ppm) supplementation. Chick skeletal muscle tissue was obtained from 28-day-old animals and used to verify apoptosis occurrence based on caspase activity detection and DNA fragmentation. Antioxidant deficiency significantly increased caspase-like activity assessed by the hydrolysis of fluorogenic peptide substrates (Abz-peptidyl-EDDnp) at lambdaexc = 320 nm and lambdaem = 420 nm. Proteolytic activation was not accompanied by typical internucleosomal DNA fragmentation detected by field inversion gel electrophoresis. Although the general caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp(O-Me) fluoromethyl ketone (Z-VAD-fmk) (0 to 80 muM) did not block caspase-like activity when preincubated for 30 min with muscle homogenates, the hydrolyzed substrates presented the same cleavage profile in HPLC (at the aspartic acid residue) when incubated with the purified recombinant enzyme caspase-3. These data indicate that oxidative stress causes caspase-like activation in muscle cells and suggest that cell death associated with exudative diathesis (dietary deficiency of selenium and vitamin E) can follow the apoptotic pathway.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de BioquímicaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de BiofísicaUniversidade de São Paulo Faculdade de Zootecnia e Engenharia de Alimentos Departamento de CiênciasUNIFESP, EPM, Depto. de BioquímicaUNIFESP, EPM, Depto. de BiofísicaSciEL

Toxicidad dermatológica en mujeres con cáncer de mama sometidas a quimioterapia

This study aimed to analyze the occurrence of skin toxicity caused by drugs used in the protocol of neoadjuvant and adjuvant chemotherapy among women with breast cancer. Patient records of 72 women who were subject to this therapy between 2003 and 2006 were assessed. Of the 558 cycles of chemotherapy, 152 adverse events were registered. There were 37 registrations of dermatological toxicity, of those, 20 were extravasations that affected 17 women. Nine reports of hardened local injury, local fibrosis, pain, and hyperemia were registered during neoadjuvancy. In adjuvancy, among the 11 extravasations registered there were reports of hardened local injury, fibrosis and local pain. Lack of follow-up records for both periods was observed. Registration of the events and reports by the nursing team are essential to monitor the sites of venous puncture during the chemotherapy treatment, besides measuring and making a photographic record of the site.O objetivo deste estudo foi analisar a ocorrência de toxicidade dermatológica, provocada por drogas utilizadas no protocolo de quimioterapia neoadjuvante e adjuvante, entre mulheres com câncer de mama. Foram avaliados 72 prontuários de mulheres submetidas a essa terapia, entre 2003 e 2006. De 558 ciclos de quimioterapia, foram registrados 152 eventos adversos, 37 de toxicidade dermatológica, e, desses, 20 eram ocorrências de extravasamento em um total de 17 mulheres. Observou-se nove ocorrências na neoadjuvância com registros nos prontuários de lesão endurecida no local, fibrose local, dor e hiperemia. Na adjuvância, dos 11 extravasamentos registrados, destacam-se lesão endurecida no local, fibrose e dor local. Houve falta de registro de seguimento e avaliação dos eventos adversos para os dois períodos. O registro das intercorrências pela equipe de enfermagem é essencial para o acompanhamento dos sítios de punções venosas, utilizados durante o tratamento quimioterápico, além da mensuração e registro fotográfico do local.El objetivo de este estudio fue analizar la ocurrencia de toxicidad dermatológica provocada por drogas utilizadas en el protocolo de quimioterapia neoadyuvante y adyuvante entre mujeres con cáncer de mama. Fueron evaluadas 72 fichas de mujeres sometidas a esta terapia de 2003 a 2006. De 558 ciclos de quimioterapia, fueron registrados 152 eventos adversos, 37 de toxicidad dermatológica; de estos, 20 fueron ocurrencias de extravasación de líquido ocurridos en un 17 mujeres. Se observó 9 ocurrencias en la quimioterapia neoadyuvante con registros en las fichas de lesión endurecida en el local, fibrosis local, dolor e hiperemia. En la quimioterapia adyuvante, de las 11 extravasaciones registradas, se destacan lesión endurecida en el local, fibrosis y dolor local. Hubo falta de registro de seguimiento y evaluación de los eventos adversos para los dos períodos. El registro de las interocurrencias por el equipo de enfermería es esencial para el acompañamiento de los sitios de punciones venosas utilizados durante el tratamiento de quimioterapia, además de mensuración y registro fotográfico del local

Structure and evolution of Subtropical Cyclone Anita as evaluated by heat and vorticity budgets

This paper explores the evolution of subtropical cyclone Anita, which occurred near the east coast of Brazil (~19.S-37.W) in March 2010. Thermodynamic and dynamic processes during Anita's lifecycle are investigated using the heat and vorticity budget equations. The cyclone developed with hybrid characteristics and moved anomalously to the southwest where it coupled with an upper level cut-off low during the mature phase. This coupling was the main dynamical mechanism for further cyclone deepening. Anita then remained quasi-stationary about 30.S -47.W for two days due to an upper level dipole pattern which prevented earlier displacement of the upper level low counterpart. When the dipole pattern dissipated, the cyclone moved southeast and underwent extratropical transition whilst merging with a mid-latitude frontal cyclone. Diabatic heating and horizontal temperature advection are found to be essential for the subtropical development. During extratropical transition, it is instead diabatic cooling together with adiabatic cooling and warm air advection that act as the main mechanisms to influence the local temperature tendencies at low levels. Low level cyclonic tendencies were mostly due to convergent flow, and the residual vorticity partially destroyed the vorticity tendencies produced by the divergence term. Moreover, in regions and levels where convection could explain some of the vorticity tendencies, it is found that apparent sinks of cyclonic vorticity were related to negative vorticity due to divergence (i.e., convergent flow), whilst apparent sources were related to positive vorticity due to divergence (i.e., divergent flow)