996 resultados para Tumor maligno de la vaina nerviosa periférica


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OBJETIVO: Investigar em ratos obesos o efeito da prática de exercício resistido sobre a sensibilidade à insulina e sobre a expressão de citocinas pró-inflamatórias e de transportador de glicose em músculo solear. MATERIAIS E MÉTODOS: Ratos Wistar alimentados com dieta hiperlipídica (grupos obesos) foram submetidos ao protocolo de exercício tipo jump squat. A sensibilidade à insulina e a expressão gênica de Tnf-α, SOCS3 e GLUT4 foram comparadas entre os grupos obesos sedentários (OS) e exercitados (OE) e controles sedentários (CS) e exercitados (CE). RESULTADOS: A sensibilidade à insulina estava reduzida no grupo OS e elevada no OE. Os conteúdos de RNAm de Tnf-α e de SOCS3 estavam aumentados no músculo esquelético do grupo OS e reduzidos no OE. O conteúdo proteico e de RNAm de GLUT4 não diferiu entre os grupos. CONCLUSÃO: O exercício resistido reverte o quadro de resistência à insulina periférica e de inflamação no músculo esquelético de obesos induzidos por dieta.

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La comunidad científica que se ocupa de los problemas relacionados con el proceso de enseñanza-aprendizaje de la físicas, ha dedicado muchos esfuerzos en los ultimos años al perfeccionamiento del mismo, motivado en primera instancia, por las demandas de renovación que el impetuoso desarrollo científico-técnico le impone en la actualidad a la enseñanza de las ciencias. En los últimos años se ha producido un desarrollo vertiginoso en la fabricación de diodos láser que emiten en el espectro visible, esto ha permitido su utilización creciente en múltiples aplicaciones y hace factible su utilización en la enseñanza aprendizaje de la física universitaria y en particular de la holografía, por sus grandes ventajas frente a los láseres convencionales de gran costo y difícil manipulación. En el trabajo se describen la instalación experimental portátil diseñada para la obtención de hologramas en la escuela y en la casa con la utilización de diodos láser, la metodología de trabajo a seguir, los métodos de procesamiento utilizados para diferentes tipos de emulsiones holográficas y un análisis de los defectos que pueden presentar los hologramas producidos y la forma de detectarlos y erradicarlos

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Cyhalothrin, a pyrethroid insecticide, induces stress-like symptoms, increases c-fos immunoreactivity in the paraventricular nucleus of the hypothalamus, and decreases innate immune responses in laboratory animals. Macrophages are key elements in cellular immune responses and operate at the tumor-host interface. This study investigated the relationship among cyhalothrin effects on Ehrlich tumor growth, serum corticosterone levels and peritoneal macrophage activity in mice. Three experiments were done with 10 experimental (single gavage administration of 3.0 mg/kg cyhalothrin daily for 7 days) and 10 control (single gavage administration of 1.0 mL/kg vehicle of cyhalothrin preparation daily for 7 days) isogenic BALB/c mice in each experiment. Cyhalothrin i) increased Ehrlich ascitic tumor growth after ip administration of 5.0 x 106 tumor cells, i.e., ascitic fluid volume (control = 1.97 ± 0.39 mL and experimental = 2.71 ± 0.92 mL; P < 0.05), concentration of tumor cells/mL in the ascitic fluid (control = 111.95 ± 16.73 x 106 and experimental = 144.60 ± 33.18 x 106; P < 0.05), and total number of tumor cells in the ascitic fluid (control = 226.91 ± 43.22 x 106 and experimental = 349.40 ± 106.38 x 106; P < 0.05); ii) increased serum corticosterone levels (control = 200.0 ± 48.3 ng/mL and experimental = 420.0 ± 75.5 ng/mL; P < 0.05), and iii) decreased the intensity of macrophage phagocytosis (control = 132.3 ± 19.7 and experimental = 116.2 ± 4.6; P < 0.05) and oxidative burst (control = 173.7 ± 40.8 and experimental= 99.58 ± 41.7; P < 0.05) in vitro in the presence of Staphylococcus aureus. These data provide evidence that cyhalothrin simultaneously alters host resistance to Ehrlich tumor growth, hypothalamic-pituitary-adrenocortical (HPA) axis function, and peritoneal macrophage activity. The results are discussed in terms of data suggesting a link between stress, HPA axis activation and resistance to tumor growth.

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Variation among natural populations of Culex (Culex) quinquefasciatus Say is associated with different vectorial capacities. The species Cx. quinquefasciatus is present in the equatorial, tropical and subtropical zones in the Brazilian territory, with intermediate forms between Cx. quinquefasciatus and Culex pipiens occurring in regions of latitudes around 33°-35°S. Herein, we studied geographically distinct populations of Cx. quinquefasciatus by genetic characterization and analysis of intra-specific wing morphometrics. After morphological analysis, molecular characterization of Cx. quinquefasciatus and intermediate forms was performed by polymerase chain reaction of the polymorphic nuclear region of the second intron of the acetylcholinesterase locus. Additionally, the morphology of adult female wings collected from six locations was analyzed. Wing centroid sizes were significantly different between some geographical pairs. Mean values of R2/R2+3 differed significantly after pairwise comparisons. The overall wing shape represented by morphometric characters could be divided into two main groupings. Our data suggest that Brazilian samples are morphologically and genetically distinct from the Argentinean samples and also indicated a morphological distinction between northern and southern populations of Brazilian Cx. quinquefasciatus. We suggest that wing morphology may be used for preliminary assessment of population structure of Cx. quinquefasciatusin Brazil

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A new criterion has been recently proposed combining the topological instability (lambda criterion) and the average electronegativity difference (Delta e) among the elements of an alloy to predict and select new glass-forming compositions. In the present work, this criterion (lambda.Delta e) is applied to the Al-Ni-La and Al-Ni-Gd ternary systems and its predictability is validated using literature data for both systems and additionally, using own experimental data for the Al-La-Ni system. The compositions with a high lambda.Delta e value found in each ternary system exhibit a very good correlation with the glass-forming ability of different alloys as indicated by their supercooled liquid regions (Delta T(x)) and their critical casting thicknesses. In the case of the Al-La-Ni system, the alloy with the largest lambda.Delta e value, La(56)Al(26.5)Ni(17.5), exhibits the highest glass-forming ability verified for this system. Therefore, the combined lambda.Delta e criterion is a simple and efficient tool to select new glass-forming compositions in Al-Ni-RE systems. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3563099]

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Background: The prostate stroma is a key mediator of epithelial differentiation and development, and potentially plays a role in the initiation and progression of prostate cancer. The tumor-associated stroma is marked by increased expression of CD90/THYI. Isolation and characterization of these stromal cells could provide valuable insight into the biology of the tumor microenvironment. Methods: Prostate CD90(+) stromal fibromuscular cells from tumor specimens were isolated by cell-sorting and analyzed by DNA microarray. Dataset analysis was used to compare gene expression between histologically normal and tumor-associated stromal cells. For comparison, stromal cells were also isolated and analyzed from the urinary bladder. Results: The tumor-associated stromal cells were found to have decreased expression of genes involved in smooth muscle differentiation, and those detected in prostate but not bladder. Other differential expression between the stromal cell types included that of the CXC-chemokine genes. Conclusion: CD90(+) prostate tumor-associated stromal cells differed from their normal counterpart in expression of multiple genes, some of which are potentially involved in organ development.

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This article presents and analyses some aspects of Georges Perec's composition as shown in his book Life: a user's manual (1978). Starting with the image of a ""book-library"", composed by some of Perec's literary 'models', and discussing the theory of intextertuality and rewriting, we propose to analyse some possible approximations between Perec and Flaubert, especially in the latter's Bouvard and Pecuchet (1881).

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Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasia and currently well recognized as a distinct entity with characteristic morphological, immunohistochemical and molecular findings. We report a case of PEComa arising in the antrum of a 71-year-old female with melena. The tumor, located predominantly in the submucosa as a well delimited nodule, measured 3.0 cm in diameter and was completely resected, with no evidence of the disease elsewhere. Histologically, it was composed predominantly of eosinophilic epithelioid cells arranged in small nests commonly related to variably sized vessels, with abundant extracellular material, moderate nuclear variation and discrete mitotic activity. No necrosis, angiolymphatic invasion or perineural infiltration was seen. Tumor cells were uniformly positive for vimentin, smooth muscle actin, desmin and melan A. Although unusual, PEComa should be considered in the differential diagnosis of gastric neoplasia with characteristic epithelioid and oncocytic features and prominent vasculature: (C) 2010 Baishideng. All rights reserved.

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Purpose: To evaluate prospectively the actual bladder perforation incidence during transurethral resection of bladder tumor (TURB) performed by residents and to identify possible predisposing factors to such condition. Patients and Methods: Thirty-four patients with bladder tumor were submitted to TURB in our academic institution in April 2006, and were prospectively studied. Procedures were all done by senior residents under an attending direct supervision. All patients had a cystograms performed after the procedure by the injection of 400 mL of saline-diluted contrast solution with low-pressure infusion through the Foley catheter. The cystograms were evaluated blindly by a single radiologist. All patients were examined by cystoscopy and/or CT every 3 months for the first 2 years postoperatively. Results: The cystogram showed contrast leaking compatible with bladder perforation in 17 (50%) cases. None of the perforations were recognized intraoperatively by the surgeon. All perforations were extraperitoneal and managed conservatively. There was no significant correlation between the incidence of bladder perforation and the patient age (p = 0.508), the tumor stage (p = 0.998), the tumor grade (p = 0.833), the number of lesions (p = 0.394), and the tumor size (p = 0.651). The only factor that had impact on the development of bladder perforation was tumor localization at the bottom of the bladder (p = 0.035; OR, 6750; 95% CI, 1.14, 39.8). Conclusion: Asymptomatic perforations of the bladder wall occur very frequently after a TURB procedure performed by residents in training and, most of the time, are not noticed by the surgeon. Localization of the tumor at bladder dome was the only factor that negatively influenced perforation rates.

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Background: Theracyte is a polytetrafluoroethylene membrane macroencapsulation system designed to induce neovascularization at the tissue interface, protecting the cells from host's immune rejection, thereby circumventing the problem of limited half-life and variation in circulating levels. Endostatin is a potent inhibitor of angiogenesis and tumor growth. Continuous delivery of endostatin improves the efficacy and potency of the antitumoral therapy. The purpose of this study was to determine whether recombinant fibroblasts expressing endostatin encapsulated in Theracyte immunoisolation devices can be used for delivery of this therapeutic protein for treatment of mice bearing B16F10 melanoma and Ehrlich tumors. Results: Mice were inoculated subcutaneously with melanoma (B16F10 cells) or Ehrlich tumor cells at the foot pads. Treatment began when tumor thickness had reached 0.5 mm, by subcutaneous implantation of 10(7) recombinant encapsulated or non-encapsulated endostatin producer cells. Similar melanoma growth inhibition was obtained for mice treated with encapsulated or non-encapsulated endostatin-expressing cells. The treatment of mice bearing melanoma tumor with encapsulated endostatin-expressing cells was decreased by 50.0%, whereas a decrease of 56.7% in tumor thickness was obtained for mice treated with non-encapsulated cells. Treatment of Ehrlich tumor-bearing mice with non-encapsulated endostatin-expressing cells reduced tumor thickness by 52.4%, whereas lower tumor growth inhibition was obtained for mice treated with encapsulated endostatin-expressing cells: 24.2%. Encapsulated endostatin-secreting fibroblasts failed to survive until the end of the treatment. However, endostatin release from the devices to the surrounding tissues was confirmed by immunostaining. Decrease in vascular structures, functional vessels and extension of the vascular area were observed in melanoma microenvironments. Conclusions: This study indicates that immunoisolation devices containing endostatin-expressing cells are effective for the inhibition of the growth of melanoma and Ehrlich tumors. Macroencapsulation of engineered cells is therefore a reliable platform for the refinement of innovative therapeutic strategies against tumors.

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Clinical trials using dendritic cells (DCs) to treat cancer patients have generated promising results in recent years. However, even simple aspects of this therapy are still not well understood, including the storage and distribution of manufactured vaccines. These processes are essential and must be elucidated in order to reduce costs. We evaluated the effects of different storage conditions on vaccine functionality using mixed lymphocyte reaction (MLR). Vaccine storage at 4 degrees C for up to 72 h had no significant effect on vaccine activity. Shipping to distant places is possible, if vaccines are kept at 4 degrees C and used up to 3 days after manufacture date.

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Background: Human Papillomavirus, HPV, is the main etiological factor for cervical cancer. Different studies show that in women infected with HPV there is a positive correlation between lesion grade and number of infiltrating macrophages, as well as with IL-10 higher expression. Using a HPV16 associated tumor model in mice, TC-1, our laboratory has demonstrated that tumor infiltrating macrophages are M2-like, induce T cell regulatory phenotype and play an important role in tumor growth. M2 macrophages secrete several cytokines, among them IL-10, which has been shown to play a role in T cell suppression by tumor macrophages in other tumor models. In this work, we sought to establish if IL-10 is part of the mechanism by which HPV tumor associated macrophages induce T cell regulatory phenotype, inhibiting anti-tumor activity and facilitating tumor growth. Results: TC-1 tumor cells do not express or respond to IL-10, but recruit leukocytes which, within the tumor environment, produce this cytokine. Using IL-10 deficient mice or blocking IL-10 signaling with neutralizing antibodies, we observed a significant reduction in tumor growth, an increase in tumor infiltration by HPV16 E7 specific CD8 lymphocytes, including a population positive for Granzyme B and Perforin expression, and a decrease in the percentage of HPV specific regulatory T cells in the lymph nodes. Conclusions: Our data shows that in the HPV16 TC-1 tumor mouse model, IL-10 produced by tumor macrophages induce regulatory phenotype on T cells, an immune escape mechanism that facilitates tumor growth. Our results point to a possible mechanism behind the epidemiologic data that correlates higher IL-10 expression with risk of cervical cancer development in HPV infected women.

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Genetic instability is frequent in human cancer. Unscheduled tetraploidization can trigger cell transformation and tumorigenesis. We made a cytogenetic analysis by Giemsa-trypsin banding of a stage I, biphasic Wilms tumor diagnosed in a 10-month-old male. An evident karyotypic heterogeneity was found. Four different subclones of tumor cells were observed, with DNA content varying from diploid to near-tetraploid complements. The genetic events involved in the acquisition of aneuploidy in Wilms tumor remain unclear. We hypothesize that initial tetraploidization caused aberrant cell division, leading to abnormal chromosomal segregation, cell transformation and tumorigenesis.

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Background: In women with breast cancer submitted to neoadjuvant chemotherapy based in doxorubicin, tumor expression of groups of three genes (PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2) have classified them as responsive or resistant. We have investigated whether expression of these trios of genes could predict mammary carcinoma response in dogs and whether tumor slices, which maintain epithelial-mesenchymal interactions, could be used to evaluate drug response in vitro. Methods: Tumors from 38 dogs were sliced and cultured with or without doxorubicin 1 mu M for 24 h. Tumor cells were counted by two observers to establish a percentage variation in cell number, between slices. Based on these results, a reduction in cell number between treated and control samples >= 21.7%, arbitrarily classified samples, as drug responsive. Tumor expression of PRSS11, MTSS1, CLPTM1 and SMYD2, was evaluated by real time PCR. Relative expression results were then transformed to their natural logarithm values, which were spatially disposed according to the expression of trios of genes, comprising PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. Fisher linear discrimination test was used to generate a separation plane between responsive and non-responsive tumors. Results: Culture of tumor slices for 24 h was feasible. Nine samples were considered responsive and 29 non-responsive to doxorubicin, considering the pre-established cut-off value of cell number reduction = 21.7%, between doxorubicin treated and control samples. Relative gene expression was evaluated and tumor samples were then spatially distributed according to the expression of the trios of genes: PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2. A separation plane was generated. However, no clear separation between responsive and non-responsive samples could be observed. Conclusion: Three-dimensional distribution of samples according to the expression of the trios of genes PRSS11, MTSS1, CLPTM1 and PRSS11, MTSS1, SMYD2 could not predict doxorubicin in vitro responsiveness. Short term culture of mammary gland cancer slices may be an interesting model to evaluate chemotherapy activity.

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In this work, we investigated the temperature dependence of short and long-range ferroelectric ordering in Pb(0.55)La(0.30)TiO(3) relaxor composition. High-resolution x-ray powder diffraction measurements revealed a clear spontaneous macroscopic cubic-to-tetragonal phase transition in the PLT relaxor sample at similar to 60 K below the maximum of the dielectric constant peak (T(m)). Indeed, the x-ray diffraction (XRD) data showed that at 300 K (above T(m) but below the Burns temperature, T(B)) the long-range order structure corresponds to a macroscopic cubic symmetry, space group number 221 (Pm-3m), whereas the data collected at 20 K revealed a macroscopic tetragonal symmetry, space group number 99 (P4mm) with c/a=1.0078, that is comparable to that of a normal ferroelectric. These results show that for samples with tetragonal composition, the long-range ferroelectric order may be recovered spontaneously at cryogenics temperatures, in contrast to ferroelectric samples with rhombohedral symmetry. On the other hand, x-ray absorption spectroscopy investigations intriguingly revealed the existence of local tetragonal disorder around Ti atoms for temperatures far below T(m) and above T(B), for which the sample presents macroscopic tetragonal and cubic symmetries, respectively. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3431024]