67 research outputs found

    Modelo digital de vulnerabilidad por incendios forestales en la provincia de Cajamarca - Perú

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    Universidad Nacional Agraria La Molina. Facultad de Ciencias Forestales. Departamento Académico de Manejo ForestalLos estudios de vulnerabilidad de la cobertura forestal son escasos en Perú por eso se llevó a cabo un análisis de la vulnerabilidad de la cobertura forestal de la provincia de Cajamarca que puede ser usado en diversas estrategias de protección y prevención de riesgos de incendios en la región. El estudio se localiza en esta región por tener registros de incendios forestales y la disposición de información para el estudio. Se evaluó la ponderación del método de análisis jerárquico, se elaboró un modelo para identificar las zonas vulnerables forestales por incendio forestal y se aplicó el modelo para identificar las zonas con vulnerabilidad forestal en la provincia de Cajamarca. Se identificaron seis factores de vulnerabilidad como son: tipo de cobertura vegetal, pendiente, centros poblados, accesibilidad, clima y combustible. Asimismo, se determinó que todos los distritos de la provincia de Cajamarca presentan zonas de vulnerabilidad alta, siendo la agricultura de la costa y sierra de la provincia, el principal contribuyente a este resultado (43,5% de la vulnerabilidad alta). Por su parte, los bosques de montaña, xéricos interandinos y montanos occidental de la provincia de Cajamarca se clasificaron con vulnerabilidad moderada.Vulnerability of forest cover studies are scarce in Peru, in order of that we carried out this approach to the analysis of forest vulnerability in the province of Cajamarca, which can be used in fire protection and prevention strategies in the region. The study is located in this region because it has forest fire records and the availability of information for the study. The weighting of the hierarchical analysis process method was evaluated, a model was constructed to identify forest vulnerable areas by forest fire and the model was applied to identify areas with forest vulnerability in the province of Cajamarca. In total, six vulnerability factors were identified, these being climate and combustibility factors (23% for both). Likewise, it was determined that all the districts of the province of Cajamarca present areas of high vulnerability, with agriculture on the coast and mountains of the province being the main contributor to this result (43.5% of high vulnerability). On the other hand, the mountain, interAndean xeric and western montane forests of the Cajamarca province were classified as moderately vulnerable

    Downregulation of SAV1 plays a role in pathogenesis of high-grade clear cell renal cell carcinoma

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    <p>Abstract</p> <p>Background</p> <p>Clinical outcome of patients with high-grade ccRCC (clear cell renal cell carcinoma) remains still poor despite recent advances in treatment strategies. Molecular mechanism of pathogenesis in developing high-grade ccRCC must be clarified. In the present study, we found that SAV1 was significantly downregulated with copy number loss in high-grade ccRCCs. Therefore, we investigated the SAV1 function on cell proliferation and apoptosis in vitro. Furthermore, we attempted to clarify the downstream signaling which is regulated by SAV1.</p> <p>Methods</p> <p>We performed array CGH and gene expression analysis of 8 RCC cell lines (786-O, 769-P, KMRC-1, KMRC-2, KMRC-3, KMRC-20, TUHR4TKB, and Caki-2), and expression level of mRNA was confirmed by quantitative RT-PCR (qRT-PCR) analysis. We next re-expressed SAV1 in 786-O cells, and analyzed its colony-forming activity. Then, we transfected siRNAs of SAV1 into the kidney epithelial cell line HK2 and renal proximal tubule epithelial cells (RPTECs), and analyzed their proliferation and apoptosis. Furthermore, the activity of YAP1, which is a downstream molecule of SAV1, was evaluated by western blot analysis, reporter assay and immunohistochemical analysis.</p> <p>Results</p> <p>We found that SAV1, a component of the Hippo pathway, is frequently downregulated in high-grade ccRCC. SAV1 is located on chromosome 14q22.1, where copy number loss had been observed in 7 of 12 high-grade ccRCCs in our previous study, suggesting that gene copy number loss is responsible for the downregulation of SAV1. Colony-forming activity by 786-O cells, which show homozygous loss of SAV1, was significantly reduced when SAV1 was re-introduced exogenously. Knockdown of SAV1 promoted proliferation of HK2 and RPTEC. Although the phosphorylation level of YAP1 was low in 786-O cells, it was elevated in SAV1-transduced 786-O cells. Furthermore, the transcriptional activity of the YAP1 and TEAD3 complex was inhibited in SAV1-transduced 786-O cells. Immunohistochemistry frequently demonstrated nuclear localization of YAP1 in ccRCC cases with SAV1 downregulation, and it was preferentially detected in high-grade ccRCC.</p> <p>Conclusions</p> <p>Taken together, downregulation of SAV1 and the consequent YAP1 activation are involved in the pathogenesis of high-grade ccRCC. It is an attractive hypothesis that Hippo signaling could be candidates for new therapeutic target.</p

    Cutoff Values of Serum IgG4 and Histopathological IgG4+ Plasma Cells for Diagnosis of Patients with IgG4-Related Disease

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    IgG4-related disease is a new disease classification established in Japan in the 21st century. Patients with IgG4-related disease display hyper-IgG4-gammaglobulinemia, massive infiltration of IgG4+ plasma cells into tissue, and good response to glucocorticoids. Since IgG4 overexpression is also observed in other disorders, it is necessary to diagnose IgG4-related disease carefully and correctly. We therefore sought to determine cutoff values for serum IgG4 and IgG4/IgG and for IgG4+/IgG+ plasma cells in tissue diagnostic of IgG4-related disease. Patients and Methods. We retrospectively analyzed serum IgG4 concentrations and IgG4/IgG ratio and IgG4+/IgG+ plasma cell ratio in tissues of 132 patients with IgG4-related disease and 48 patients with other disorders. Result. Serum IgG4 >135  mg/dl demonstrated a sensitivity of 97.0% and a specificity of 79.6% in diagnosing IgG4-related disease, and serum IgG4/IgG ratios >8% had a sensitivity and specificity of 95.5% and 87.5%, respectively. IgG4+cell/IgG+ cell ratio in tissues >40% had a sensitivity and specificity of 94.4% and 85.7%, respectively. However, the number of IgG4+ cells was reduced in severely fibrotic parts of tissues. Conclusion. Although a recent unanimous consensus of all relevant researchers in Japan recently established the diagnostic criteria for IgG4-related disease, findings such as ours indicate that further discussion is needed

    Genomic Profiling of Submucosal-Invasive Gastric Cancer by Array-Based Comparative Genomic Hybridization

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    Genomic copy number aberrations (CNAs) in gastric cancer have already been extensively characterized by array comparative genomic hybridization (array CGH) analysis. However, involvement of genomic CNAs in the process of submucosal invasion and lymph node metastasis in early gastric cancer is still poorly understood. In this study, to address this issue, we collected a total of 59 tumor samples from 27 patients with submucosal-invasive gastric cancers (SMGC), analyzed their genomic profiles by array CGH, and compared them between paired samples of mucosal (MU) and submucosal (SM) invasion (23 pairs), and SM invasion and lymph node (LN) metastasis (9 pairs). Initially, we hypothesized that acquisition of specific CNA(s) is important for these processes. However, we observed no significant difference in the number of genomic CNAs between paired MU and SM, and between paired SM and LN. Furthermore, we were unable to find any CNAs specifically associated with SM invasion or LN metastasis. Among the 23 cases analyzed, 15 had some similar pattern of genomic profiling between SM and MU. Interestingly, 13 of the 15 cases also showed some differences in genomic profiles. These results suggest that the majority of SMGCs are composed of heterogeneous subpopulations derived from the same clonal origin. Comparison of genomic CNAs between SMGCs with and without LN metastasis revealed that gain of 11q13, 11q14, 11q22, 14q32 and amplification of 17q21 were more frequent in metastatic SMGCs, suggesting that these CNAs are related to LN metastasis of early gastric cancer. In conclusion, our data suggest that generation of genetically distinct subclones, rather than acquisition of specific CNA at MU, is integral to the process of submucosal invasion, and that subclones that acquire gain of 11q13, 11q14, 11q22, 14q32 or amplification of 17q21 are likely to become metastatic
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