911 resultados para tumor sampling


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Objective: We aimed to evaluate the inactivation of COX-2, HMLH1 and CDKN2A by promoter methylation and its relationship with the infection by different Helicobacter pylori strains in gastric cancer. Methods: DNA extracted from 76 H. pylori-positive gastric tumor samples was available for promoter methylation identification by methylation-specific PCR and H. pylori subtyping by PCR. Immunohistochemistry was used to determine COX-2, p16(INK4A) and HMLH1 expression. Results: A strong negative correlation was found between the expression of these markers and the presence of promoter methylation in their genes. Among cardia tumors, negativity of p16(INK4A) was a significant finding. on the other hand, in noncardia tumors, the histological subtypes had different gene expression patterns. In the intestinal subtype, a significant finding was HMLH1 inactivation by methylation, while in the diffuse subtype, CDKN2A inactivation by methylation was the significant finding. Tumors with methylated COX-2 and HMLH1 genes were associated with H. pylori vac A s1 (p = 0.025 and 0.047, respectively), and the nonmethylated tumors were associated with the presence of the gene flaA. Conclusions: These data suggest that the inactivation of these genes by methylation occurs by distinct pathways according to the histological subtype and tumor location and depends on the H. pylori genotype. Copyright (C) 2011 S. Karger AG, Basel

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Species richness is central to ecological theory, with practical applications in conservation, environmental management and monitoring. Several techniques are available for measuring species richness and composition of amphibians in breeding pools, but the relative efficacy of these methods for sampling high-diversity Neotropical amphibian fauna is poorly understood. I evaluated seven studies from south and south-eastern Brazil to compare the relative and combined effectiveness of two methods for measuring species richness at anuran breeding pools: acoustic surveys with visual encounter of adults and dipnet surveys of larvae. I also compared the relative efficacy of each survey method in detecting species with different reproductive modes. Results showed that both survey methods underestimated the number of species when used separately; however, a close approximation of the actual number of species in each breeding pool was obtained when the methods were combined. There was no difference between survey methods in detecting species with different reproductive modes. These results indicate that researchers should employ multiple survey methods that target both adult and larval life history stages in order to accurately assess anuran species richness at breeding pools in the Neotropics.

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To investigate the feasibility and validity of sampling blood from the carpal pad in hospitalised healthy and diabetic dogs. METHODS The carpal pad was compared to the ear as a sampling site in 60 dogs (30 healthy and 30 diabetic dogs). RESULTS Lancing the pads was very well tolerated. The average glucose concentrations in blood samples obtained from the ears and carpal pads exhibited a strong positive correlation (r = 0.938) and there were no significant differences between them (P = 0.914). In addition, 98.3% of the values obtained were clinically acceptable when assessed by the error grid analysis. CLINICAL SIGNIFICANCE The carpal pad is a good alternative sampling site for home monitoring, especially in animals with a soft and/or light-coloured pad.

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Chronic sclerosing sialadenitis is an uncommon cause of salivary gland enlargement mainly occurring in the fifth and seventh decade of life. In the Western population, chronic sclerosing sialadenitis has been characterized as an IgG4-related disease. Although rare, this lesion occurs in children. To increase awareness about this entity in the pediatric age group, we report the case of an 11-year-old boy with a hard, 4.0-cm circumscribed mass in the right submandibular gland. Histologically there was marked distortion of the gland architecture by a dense lymphocytic infiltrate and extensive fibrosis with septa that crossed and distorted the gland, leaving atrophic acini and dilated, irregular ducts. The lymphoid infiltrate formed multiple follicles with active germinal centers, numerous plasma cells, and areas with diffuse arrangement. Immunophenotyping showed abundant CD20- and CD3-positive lymphocytes; cytokeratin AE1/AE3 highlighted the distorted architectural pattern; IgG staining showed large numbers of positive cells infiltrating the interstitium and surrounding the atrophic acini and ducts. IgG4 staining revealed a large proportion of positive infiltrating elements. Kuttner tumor belongs to the group of IgG4-related sclerosing diseases. The differential diagnosis includes pleomorphic adenoma and other salivary gland neoplasms. Its recognition in children is important clinically because this entity is amenable to steroid treatment, and additional work up and follow up is warranted to stave off other IgG4-related diseases/complications.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Walker's 256 carcinoma changes its behaviour as a consequence of various factors. In this paper the authors compare the evolution of 2 lines of the tumor: WM 16 (muscular) and Christ Hospital (ascitic) both inoculated intramuscularly. Animals receiving line WM 16 had a severe rapidly progressive evolution dying around day 14 after inoculation with diffuse metastases to lymph nodes (65% of animals), kidneys (53%), spleen (50%), lungs (46.5%), liver (45%), bone marrow (44.8%), in 56% of the animals there were circulating tumoral cells. Animals receiving the Christ Hospital line survived up to 40 days, metastases were limited to lungs (48.7%) and lymph nodes (31.7%) and only in 2 of 45 animals circulating tumoral cells were observed.

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To study the histogenesis of spindle and epithelioid cell tumors of gastrointestinal tract we evaluated ten cases of gastrointestinal stromal tumors (GIST) previously classified as leiomyomas (6 cases) and leiomyosarcomas (4 cases). The cases were studied by morphological and immunohistochemistry procedures with search of three markers: muscle specific actin (HHF-35), vimentin and S-100 protein. All tumors showed vimentin positivity. Muscle differentiation was demonstrated in three cases (33.3%), all of them benign. One tumor, in small intestine, displayed S-100 protein positivity. The results showed that the GIST represent a heterogeneous group of tumors, most of which consist of primitive mesenchymal cells.

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Recent theoretical studies have shown that the X̄ chart with variable sampling intervals (VSI) and the X̄ chart with variable sample size (VSS) are quicker than the traditional X̄ chart in detecting shifts in the process. This article considers the X̄ chart with variable sample size and sampling intervals (VSSI). It is assumed that the amount of time the process remains in control has exponential distribution. The properties of the VSSI X̄ chart are obtained using Markov chains. The VSSI X̄ chart is even quicker than the VSI or VSS X̄ charts in detecting moderate shifts in the process.

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To evaluate the relationship between carotenoid concentrations in serum and breast tissue, we measured serum carotenoid concentrations and endogenous carotenoid levels in breast adipose tissue of women with benign breast tumor (n = 46) or breast cancer (n = 44). Before extraction, serum was digested with lipase and cholesterol esterase, and breast adipose tissue was saponified. Serum and tissue carotenoids were extracted with ether/hexane and measured by using HPLC with a C30 column. Serum retinoic acid was extracted with chloroform/methanol and measured using HPLC with a C18 column. There were no significant differences in serum carotenoids [lutein, zeaxanthin, cryptoxanthin (both α- and β-), α-carotene, all-trans β-carotene, 13-cis β-carotene and lycopene], retinoids (retinol, all-trans and 13-cis retinoic acids), and α- and -γ- tocopherol concentrations between benign breast tumor patients and breast cancer patients. A substantial amount of 9-cis β- carotene was present in adipose tissue and was the only carotenoid that had a significantly lower level in benign breast tumor patients than in breast cancer patients. Correlations between carotenoid concentrations in serum and in breast adipose tissue were determined by combining the data of the two groups. Concentrations of the major serum carotenoids except cryptoxanthin showed significant correlations with breast adipose tissue carotenoid levels. When the concentrations of serum carotenoids were adjusted for serum triglycerides or LDL, correlations between serum carotenoid concentrations and breast adipose tissue carotenoid levels markedly increased, including that of cryptoxanthin (P <0.001). The strong correlation between serum carotenoid concentrations and endogenous breast adipose tissue carotenoid levels indicate that dietary intake influences adipose tissue carotenoid levels as well as serum concentrations, and that adipose tissue is a dynamic reservoir of fat-soluble nutrients.

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A standard X̄ chart for controlling the process mean takes samples of size n0 at specified, equally-spaced, fixed-time points. This article proposes a modification of the standard X chart that allows one to take additional samples, bigger than n0, between these fixed times. The additional samples are taken from the process when there is evidence that the process mean moved from target. Following the notation proposed by Reynolds (1996a) and Costa (1997) we shortly call the proposed X chart as VSSIFT X chart where VSSIFT means variable sample size and sampling intervals with fixed times. The X chart with the VSSIFT feature is easier to be administered than a standard VSSI X chart that is not constrained to sample at the specified fixed times. The performances of the charts in detecting process mean shifts are comparable. Copyright © 1998 by Marcel Dekker, Inc.

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Objective and Design: To determine the alpha-2-macroglobulin (alpha2M) levels in mice during acute and chronic inflammatory responses. Materials and Methods: Inflammation was induced by one of the following stimuli: carrageenin, zymosan, lipopolysacharide, thioglycollate, bacilli Calmette Guerin, PPD (in pre-immunized and non-immunized animals) and tumor cells. The concentration of alpha2M was determined in plasma or peritoneal liquid by electroimmunoassay. Results: In all the treatments employed, the plasma levels of alpha2M were higher than in untreated animals. This increase varied from 9%, 24 h after injection up a maximum of 66% 72 h post-injection. When compared to animals injected only with saline, the increases were significant 48 h after treatment with either zymosan or LPS, and 72 h after treatment with either thioglycollate or carrageenin. Treatment with BCG triggers an increase in alpha2M levels after 24 h (18.60%) and 48 h (27.90%). Immunized mice presented higher levels of this protein than non-immunized animals after challenge with PPD. The growth of Ehrlich tumor cells in the peritoneal cavity was directly correlated with the local levels of alpha2M which increased 3.5 fold, 10 days after injection. Conclusions: These results strongly indicate that in mice, the concentration of alpha2M can increase during acute and chronic inflammatory reactions with kinetics dependent on the particular kind of inflammatory agent.

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Recent studies have shown that the X̄ chart with variable sampling intervals (VSI) and/or with variable sample sizes (VSS) detects process shifts faster than the traditional X̄ chart. This article extends these studies for processes that are monitored by both the X̄ and R charts. A Markov chain model is used to determine the properties of the joint X and R charts with variable sample sizes and sampling intervals (VSSI). The VSSI scheme improves the joint X̄ and R control chart performance in terms of the speed with which shifts in the process mean and/or variance are detected.