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thiago gomes

    thiago gomes

    Double strand break lesions, the most toxic type of DNA damage, are repaired primarily through 2 distinct pathways: homology-directed recombination (HR) and non-homologous end-joining (NHEJ). BRCA1 and 53BP1, 2 proteins containing the... more
    Double strand break lesions, the most toxic type of DNA damage, are repaired primarily through 2 distinct pathways: homology-directed recombination (HR) and non-homologous end-joining (NHEJ). BRCA1 and 53BP1, 2 proteins containing the BRCT modular domain, play an important role in DNA damage response (DDR) by orchestrating the decision between HR and NHEJ, but the precise mechanisms regarding both pathways are not entirely understood. Previously, our group identified a putative interaction between BRCA1 and BARD1 (BRCA1-associated RING domain 1) and the cyclin-dependent kinase (CDK9). CDK9 is a component of the positive transcription elongation complex and has been implicated in genome integrity maintenance associated with the replication stress response. Here we show that CDK9 interacts with endogenous BRCA1 and BARD1 mediated by their RING finger and BRCT domains, and describe CDK9 ionizing radiation-induced foci (IRIF) formation and its co-localization with BRCA1 in DNA damage sites. Cells lacking CDK9 are characterized by an altered γ-H2AX foci dynamics after DNA damage, a reduced efficiency in HR but not in NHEJ repair, failure to form BRCA1 and RAD51 IRIF and increased sensitivity to genotoxic agents. These data indicate that CDK9 is a player in the DDR and is consistent with its participation in HR pathway by modulating BRCA1 response.
    To evaluate the destruction complex of beta-catenin by the expression of the proteins beta-catetenin, adenomatous polyposis coli, GSK3β, axin and ubiquitin in colorectal carcinoma and colonic adenoma. Tissue samples from 64 patients with... more
    To evaluate the destruction complex of beta-catenin by the expression of the proteins beta-catetenin, adenomatous polyposis coli, GSK3β, axin and ubiquitin in colorectal carcinoma and colonic adenoma. Tissue samples from 64 patients with colorectal carcinoma and 53 patients with colonic adenoma were analyzed. Tissue microarray blocks and slides were prepared and subjected to immunohistochemistry with polyclonal antibodies in carcinoma, adjacent non-neoplastic mucosa, and adenoma tissues. The immunoreactivity was evaluated by the percentage of positive stained cells and by the intensity assessed through of the stained grade of proteins in the cytoplasm and nucleus of cells. In the statistical analysis, the Spearman correlation coefficient, Student's t, χ2, Mann-Whitney, and McNemar tests, and univariate logistic regression analysis were used. In colorectal carcinoma, the expressions of beta-catenin and adenomatous polyposis coli proteins were significantly higher than in colonic ...
    The interaction between cellulose and xylan is important for the load-bearing secondary cell wall of flowering plants. Based on the precise even-spaced pattern of acetyl and glucuronosyl (MeGlcA) xylan substitutions in eudicots, we... more
    The interaction between cellulose and xylan is important for the load-bearing secondary cell wall of flowering plants. Based on the precise even-spaced pattern of acetyl and glucuronosyl (MeGlcA) xylan substitutions in eudicots, we recently proposed that an unsubstituted face of xylan in a two-fold helical screw can hydrogen bond to the hydrophilic surfaces of cellulose microfibrils. In gymnosperm cell walls, any role for xylan is unclear, and glucomannan is thought to be the important cellulose-binding polysaccharide. Here, we analysed xylan from the secondary cell walls of the four gymnosperm lineages (Conifer, Gingko, Cycad and Gnetophyta). Conifer, Gingko and Cycad xylan lacks acetylation, but is modified by arabinose and MeGlcA. Interestingly, the arabinosyl substitutions are located two xylosyl residues from MeGlcA, which is itself placed precisely on every sixth xylosyl residue. Notably, the Gnetophyta xylan is more akin to early-branching angiosperms and eudicot xylan, lacki...
    Improving the process of how physical performance is enhanced is one of the main topics evaluated by physiologists. This process often involves athletes and nonathletic populations. The purpose of this study was to assess the chronic... more
    Improving the process of how physical performance is enhanced is one of the main topics evaluated by physiologists. This process often involves athletes and nonathletic populations. The purpose of this study was to assess the chronic response to 10 weeks of static stretching exercises carried out before and during a strength training program for 8 exercises on an 8 repetition maximum (8RM) test performance, and basal serum insulinlike growth factor (IGF-1) levels. Thirty recreationally trained volunteers were randomly assigned to 1 of 3 training groups: (a) SBST (performed a warm-up with a static stretching protocol before each strength training session); (b) SDST (before each training set, a static stretching exercise was performed); and (c) OST (entire session was performed without any type of stretching exercise). Strength and IGF-1 levels were collected at the beginning (pretest) and end (posttest) of the entire experimental procedure. All the exercises showed a significant increase in muscle strength for the OST group. However, the results revealed a significant increase in the muscle strength for only a few exercises in the SBST (LP, LE) and SDST (LP) experimental conditions. Significant statistical differences were found between SBST and SDST for all the exercises in the OST experimental condition. Furthermore, the IGF-1 expression showed no significant differences in the intragroup analysis. However, the OST group showed higher values (p < 0.05) in the posttest when compared with those of the other groups (increased significantly only in the OST experimental condition). It has been concluded that, although all the groups showed an increase in muscular strength, the strength training performed without any type of stretching exercise, regardless of whether the stretching is performed before or during the lifting session, can more effectively increase muscle strength and basal serum IGF-1 levels. It was concluded that strength training, with or without the use of stretching exercises, increased muscular strength in the studied groups, and can induce an increase in IGF-1 levels.
    Page 1. Acute effect of passive rest intervals and stretching exercise on multiple set performance Antonio Claudio do Rosário Souza, Carmen Lúcia Borges Bastos, Maria de Nazaré Dias Portal, Belmiro Freitas de Salles, Thiago Matassoli... more
    Page 1. Acute effect of passive rest intervals and stretching exercise on multiple set performance Antonio Claudio do Rosário Souza, Carmen Lúcia Borges Bastos, Maria de Nazaré Dias Portal, Belmiro Freitas de Salles, Thiago Matassoli Gomes, Jefferson da Silva Novaes ...
    The objective of this paper was to study the morphology of the articular disc and analyze the immunohistochemical expression of the marker of type IV collagen in the articular disc of the temporomandibular joint (TMJ) of human fetuses of... more
    The objective of this paper was to study the morphology of the articular disc and analyze the immunohistochemical expression of the marker of type IV collagen in the articular disc of the temporomandibular joint (TMJ) of human fetuses of different gestational ages. Twenty TMJ from human fetuses aging from 21 to 24 weeks of intrauterine life were studied. The TMJ were supplied by the Federal University of Uberaba. The ages of the fetuses were determined by measuring the crown-rump length (CRL). Macroscopically, the fetuses were fixed in a formalin solution at 10% and dissected by removing the skin and the subcutaneous tissue, exposing the deep structures. An immunohistochemical marker of type IV collagen was used in order to characterize the presence of blood vessels in the central region of the temporomandibular joint disc. Analysis of the immunohistochemical marker of type IV collagen showed the presence of blood vessels in the central region of the temporomandibular disc in human fetuses.
    The aim of this study was to evaluate the expression of FASL, FAS and FADD and caspase-3 in oesophagus, stomach and colonic tissues of mice irradiated in vivo by immunohistochemistry. A total of 48 adult male C57BL mice were distributed... more
    The aim of this study was to evaluate the expression of FASL, FAS and FADD and caspase-3 in oesophagus, stomach and colonic tissues of mice irradiated in vivo by immunohistochemistry. A total of 48 adult male C57BL mice were distributed into four groups: Ami(-)/Rad(-): Mice received 0.5 ml of 0.9% physiological saline solution (PPS) intraperitioneally (i.p.); Ami(+)/Rad(-): mice received amifostine (400mg/kg i.p.) freshly dissolved in double-distilled water; Ami(-)/Rad(+): mice received 0.5 ml of PSS i.p. 30 min before a single whole-body radiation dose of 7 Gy; Ami(+)/Rad(+): mice received 0.5 ml of an aqueous solution of 400 mg/kg amifostine i.p.30 min prior to irradiation. All groups were assigned into subgroups sacrificed at 0.5 h, 1 h, 2 h and 4 h after irradiation. In oesophagus and stomach tissues, we did not observe any difference between Ami(-)/ad(-), Ami(+)/Rad(-), Ami(-)/Rad(+) and Ami(+)/Rad(+) groups in the expression of FASL, FAS and FADD. The colonic tissue was the on...
    ABSTRACT We present EMFlow, a very efficient algorithm and its implementation, to compute the drainage network (i.e. the flow direction and flow accumulation) on huge terrains stored in external memory. Its utility lies in processing the... more
    ABSTRACT We present EMFlow, a very efficient algorithm and its implementation, to compute the drainage network (i.e. the flow direction and flow accumulation) on huge terrains stored in external memory. Its utility lies in processing the large volume of high resolution terrestrial data newly available, which internal memory algorithms cannot handle efficiently. The flow direction is computed using an adaptation of our previous method RWFlood that uses a flooding process to quickly remove internal depressions or basins. Flooding, proceeding inward from the outside of the terrain, works oppositely to the common method of computing downhill flow from the peaks. To reduce the number of I/O operations, EMFlow adopts a new strategy to subdivide the terrain into islands that are processed separately. The terrain cells are grouped into blocks that are stored in a special data structure managed as a cache memory. EMFlow’s execution time was compared against the two most recent and most efficient published methods: TerraFlow and r.watershed.seg. It was, on average, 25 and 110 times faster than TerraFlow and r.watershed.seg respectively. Also, EMFlow could process larger datasets. Processing a 50000 × 50000 terrain on a machine with 2GB of internal memory took about 4500 seconds, compared to 87000 seconds for TerraFlow while r.watershed.seg failed on terrains larger than 15000 ×15000. On very small, say1000 ×1000 terrains, EMFlow takes under a second, compared to 6 and 20 seconds in r.watershed.seg and TerraFlow respectively. So EMFlow could be a component of a future interactive system where a user could modify terrain and immediately see the new hydrography.
    ... Celina Tizuko Fujiyama Oshima1 ... Acta Cytol. 1979;23(1):75-80. 9. Bandlish U, Kapoor K, Shukla S. Efficacy of a modified ultrafast Papanicolaou (UFP) stain for breast aspirates. J Indian Med Assoc. 2004;102(6):309;312;326. 10. ...
    ABSTRACT We present a very efficient algorithm, named EMFlow, and its implementation to compute the drainage network, that is, the flow direction and flow accumulation on huge terrains stored in external memory. It is about 20 times... more
    ABSTRACT We present a very efficient algorithm, named EMFlow, and its implementation to compute the drainage network, that is, the flow direction and flow accumulation on huge terrains stored in external memory. It is about 20 times faster than the two most recent and most efficient published methods: TerraFlow and r.watershed.seg. Since processing large datasets can take hours, this improvement is very significant. The EMFlow is based on our previous method RWFlood which uses a flooding process to compute the drainage network. And, to reduce the total number of I/O operations, EMFlow is based on grouping the terrain cells into blocks which are stored in a special data structure managed as a cache memory. Also, a new strategy is adopted to subdivide the terrains in islands which are processed separately. Because of the recent increase in the volume of high resolution terrestrial data, the internal memory algorithms do not run well on most computers and, thus, optimizing the massive data processing algorithm simultaneously for data movement and computation has been a challenge for GIS.
    ABSTRACT INTRODUCTION/OBJECTIVE: The tissue microarray (TMA) technique allows the evaluation of multiple tissue samples in a single block. One of the problems of TMA is the ungluing of tissue sections, thus commercial adhesive tape has... more
    ABSTRACT INTRODUCTION/OBJECTIVE: The tissue microarray (TMA) technique allows the evaluation of multiple tissue samples in a single block. One of the problems of TMA is the ungluing of tissue sections, thus commercial adhesive tape has been used to reduce this loss. There are no reports comparing the use of the commercial adhesive tape with the use of the modified silane-coated technique. The objective of this study was to compare section loss in slides using commercial adhesive tape, silane-coated microslides with the conventional technique or with the modified technique. MATERIAL AND METHOD: The TMA was constructed with hepatic tissue blocks embedded in paraffin, using a fixed base device, placing 32 cylinders of 2 mm in diameter in duplicate and 2.2 mm apart from each other. Fifteen 4-µm sections were placed on conventional silane-coated microslides at 4% (Group 1), 15 on silane-coated microslides with a modified technique (6% of silane and minimum use of acetone) (Group 2), and 15 on slides using commercial adhesive tape, according to the manufacturer's recommendations (Group 3). All microslides were processed by immunohistochemistry for cytokeratin 18, with antigen retrieval accomplished by incubation with citrate buffer pH 6.0 with microwave enhancement. Samples loss was quantified and expressed as: total (> 80%), almost complete (75% to 79%) or partial (50% to 74%). RESULTS: The loss of sections was similar in all three groups (4.9 vs. 3.1 vs. 8.1, respectively) (analysis of variance [ANOVA], p = 0.3654). One slide using commercial adhesive tape showed artifactual ungluing of all sections and another one showed loss of 20 samples on one side of the slide. None of the silane-coated microslides showed such artifact. CONCLUSIONS: Silane-coated microslides show adequate results, require less technical training and reduce the cost of TMA procedure, what justifies their use in research. Moreover, the use of the modified silane-coating technique, with the reduction of acetone volume, lowers the costs and reduces chemical residues.
    The aim of this study was to investigate the expressions of cell cycle regulatory proteins such as p53, p16, p21, and Rb in squamous cell carcinoma of the oropharynx and their relation to histological differentiation, staging of disease,... more
    The aim of this study was to investigate the expressions of cell cycle regulatory proteins such as p53, p16, p21, and Rb in squamous cell carcinoma of the oropharynx and their relation to histological differentiation, staging of disease, and prognosis. Paraffin blocks from 21 primary tumors were obtained from archives of the Department of Pathology, Paulista Medical School, Federal University of Sao Paulo, UNIFESP/EPM. Immunohistochemistry was used to detect the expression of p53, p16, p21, and Rb by means of tissue microarrays. Expression of p53, p21, p16 and Rb was not correlated with the stage of disease, histopathological grading or recurrence in squamous cell carcinoma of the oropharynx. Taken together, our results suggest that p53, p16, p21 and Rb are not reliable biomarkers for prognosis of the tumor severity or recurrence in squamous cell carcinoma of the oropharynx as depicted by tissue microarrays and immunohistochemistry.
    Adjuvant or neoadjuvant chemoradiotherapy (CRT) increases the survival rates significantly, but it also increases morbidity. Molecular markers may help on prognosis evaluation and treatment choice. The purpose of this study is to evaluate... more
    Adjuvant or neoadjuvant chemoradiotherapy (CRT) increases the survival rates significantly, but it also increases morbidity. Molecular markers may help on prognosis evaluation and treatment choice. The purpose of this study is to evaluate the imunoexpression of p53 and Ki-67 in rectal cancer tissue after CRT treatment. Stage II or III rectal cancer patients were evaluated and treated with RT and 5-FU preoperatively (neoadjuvant treatment, NG) or after surgical resection of the cancer (adjuvant treatment, AG). Thirty-one patients were enrolled in the NG and 30 in the AG; 63.95% were between 50 and 70 years, 50.8% were male, and 53% were in stage III. Of the tumors, 64.5% of the NG and 63.34% of the AG had not overexpressed p53 (p = 0.865) and 9.67% of NG and 33.33% of the AG tumors had a high proliferative index (HPI) of Ki67, p = 0.052. We have not found any difference among metastasis development in the groups (p = 0.708). After 5 years, patients with low proliferative index (LPI) ...
    This study was undertaken to investigate the immunoexpression of Bcl-2 family proteins (Bcl-2, Bcl-x, Bax, Bak and Bad) and to evaluate the correlation between the immunoexpression of these proteins and that of cleaved caspase 3, Ki-67... more
    This study was undertaken to investigate the immunoexpression of Bcl-2 family proteins (Bcl-2, Bcl-x, Bax, Bak and Bad) and to evaluate the correlation between the immunoexpression of these proteins and that of cleaved caspase 3, Ki-67 and p53. A tissue microarray (TMA) paraffin block was constructed using gastric carcinoma tissue (test group) and adjacent normal gastric mucosa (control group) from 87 patients who had not previously undergone radiotherapy or chemotherapy. Sections from the TMA block (4 µm) were subjected to immunohistochemistry for Bcl-2, Bcl-x, Bax, Bak, Bad, p53, Ki-67 and cleaved caspase-3. The slides were evaluated by the semi-quantitative method, and the scores obtained (intensity vs. percentage of staining) were correlated with one another and with the apoptotic index, cellular proliferation and data regarding patient survival. The studied proteins were present in the tumor tissue and in the normal gastric mucosa, but at different intensities and with differen...
    Heat shock proteins are molecular chaperones that may be constitutively present in cells protecting them from various stresses, such as extreme temperature, anoxia or chemical agents. Cervical cancer is the second most prevalent... more
    Heat shock proteins are molecular chaperones that may be constitutively present in cells protecting them from various stresses, such as extreme temperature, anoxia or chemical agents. Cervical cancer is the second most prevalent malignancy of women. In this study, we analyzed the expression of Hsp27 by immunohistochemistry in cervical intraepithelial lesions of Brazilian women, along with samples from non neoplasic lesions (NN). Cervical intraepithelial neoplasia I (CIN I), II (CIN II) and III (CIN III)/in situ carcinoma and squamous cell carcinoma (SCC) were included. Immunostaining was observed in 30 (100%) samples of NN, 46 (92%) in CIN I, 50 (100%) in CIN II, 52 (98.11%) in CIN III/CIS, and 46 (98.11%) in SCC. In group NN Hsp27 immunostaining was heterogeneous, more intense in basal and parabasal layers of the epithelium and less or absent in the intermediate and superficial layer. The majority of the samples of CIS and SCC presented strong staining in allepithelial layers. Meta...
    Page 1. “main” — 2009/6/10 — 16:46 — page 149 — #1 Journal of Computational Interdisciplinary Sciences (2009) 1(2): 149-157 © 2009 Pan-American Association of Computational Interdisciplinary Sciences ISSN 1983-8409 http://epacis.org ...
    The interaction between xylan and cellulose microfibrils is important for secondary cell wall properties in vascular plants; however, the molecular arrangement of xylan in the cell wall and the nature of the molecular bonding between the... more
    The interaction between xylan and cellulose microfibrils is important for secondary cell wall properties in vascular plants; however, the molecular arrangement of xylan in the cell wall and the nature of the molecular bonding between the polysaccharides are unknown. In dicots, the xylan backbone of β-(1,4)-linked xylosyl residues is decorated by occasional glucuronic acid, and approximately one-half of the xylosyl residues are O-acetylated at C-2 or C-3. We recently proposed that the even, periodic spacing of GlcA residues in the major domain of dicot xylan might allow the xylan backbone to fold as a twofold helical screw to facilitate alignment along, and stable interaction with, cellulose fibrils; however, such an interaction might be adversely impacted by random acetylation of the xylan backbone. Here, we investigated the arrangement of acetyl residues in Arabidopsis xylan using mass spectrometry and NMR. Alternate xylosyl residues along the backbone are acetylated. Using molecul...
    The aim of the present study was to detect the relative expressions of p53, p21(Waf1/Cip1), p27(Kip1) Bcl-2 and cleaved caspase-3 in cervical lesion samples from Brazilian women by immunohistochemistry. A total of 230 cervical biopsies in... more
    The aim of the present study was to detect the relative expressions of p53, p21(Waf1/Cip1), p27(Kip1) Bcl-2 and cleaved caspase-3 in cervical lesion samples from Brazilian women by immunohistochemistry. A total of 230 cervical biopsies in paraffin-embedded blocks were studied: 43 were invasive squamous cell carcinomas (SCC), 52 carcinomas in situ/cervical intraepithelial neoplasias III (CIN III), 54 cervical intraepithelial neoplasias II (CIN II), 51 cervical intraepithelial neoplasias I (CIN I) and 30 non-neoplastic lesions (NN) with benign cellular changes. Significant differences were observed in the p53 expression between the different groups: NN and CIN I (p=0.010); NN and CIN II (p<0.00001); CIN II and CIN III (p=0.02); CIN II and CIS (p=0.0220); CIN II and CEC (p=0.010). Regarding p21(WAF1/Cip1), significant differences were observed between NN and CEC (p=0.001); CIN I and CEC (p=0.001); CIN II and CIN III (p=0,001); CIN II and CIS (p=0.0004) and CIN II and CEC (p<0.000...
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    Legionnaires' disease is a severe form of pneumonia, with worldwide relevance, caused by Legionella spp. Approximately 90% of all cases of legionellosis are caused by Legionella pneumophila, but other species can also be responsible... more
    Legionnaires' disease is a severe form of pneumonia, with worldwide relevance, caused by Legionella spp. Approximately 90% of all cases of legionellosis are caused by Legionella pneumophila, but other species can also be responsible for this infection. These bacteria are transmitted by inhalation of aerosols or aspiration of contaminated water. In Spain, environmental studies have demonstrated the presence of Legionella non-pneumophila species in drinking water treatment plants and water distribution networks. Aware that this evidence indicates a risk factor and the lack of routine assays designed to detect simultaneously diverse Legionella species, we analyzed 210 urine samples from patients presenting clinical manifestations of pneumonia using a semi-nested PCR for partial amplification of the 16S rDNA gene of Legionella and a diagnostic method used in hospitals for Legionella antigen detection. In this study, we detected a total of 15 cases of legionellosis (7.1%) and the fir...

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