990 resultados para Malignant obstruction


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Bone marrow and peripheral blood leukocytes from 19 leukemia patients were found to contain telomerase activity detectable by a PCR-based assay. Telomerase was also detectable in nonmalignant bone marrow and peripheral blood leukocytes from normal donors, including fractions enriched for granulocytes, T lymphocytes, and monocytes/B cells. Semiquantitative comparison revealed considerable overlap between telomerase activities in samples from normal subjects and leukemia patients, confounding evaluation of the role of telomerase in this disease. These data indicate that human telomerase is not restricted to immortal cells and suggest that the somatic expression of this enzyme may be more widespread than was previously inferred from the decline of human telomeres.

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To assess the role of altered alpha 2 beta 1 integrin expression in breast cancer, we expressed the alpha 2 beta 1 integrin de novo in a poorly differentiated mammary carcinoma that expressed no detectable alpha 2-integrin subunit. Expression of the alpha 2 beta 1 integrin resulted in a dramatic phenotypic alteration from a fibroblastoid, spindle-shaped, non-contact-inhibited, motile, and invasive cell to an epithelioid, polygonal-shaped, contact-inhibited, less motile, and less invasive cell. Although expression of the alpha 2 subunit did not alter adhesion to collagen, it profoundly altered cell spreading. Re-expression of the alpha 2 beta 1 integrin restored the ability to differentiate into gland-like structures in three-dimensional matrices and markedly reduced the in vivo tumorigenicity of the cells. These results indicate that the consequences of diminished alpha 2 beta 1-integrin expression in the development of breast cancer and, presumably, of other epithelial malignancies are increased tumorigenicity and loss of the differentiated epithelial phenotype.

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The rapid progress in the cloning of proteoglycan genes has enabled investigators to examine in depth the functional roles these polyhedric molecules play in the control of cell proliferation. Decorin, a leucine-rich proteoglycan expressed by most connective tissues, is a prototype molecule that regulates cellular growth via two mechanisms: modulation of growth factor activity and matrix assembly. We now provide direct evidence that human colon cancer cells stably transfected with decorin cDNA exhibit a marked suppression of the transformed phenotype: the cells have a reduced growth rate in vitro, form small colonies in soft agar, and do not generate tumors in scid/scid mice. Several independent clones are arrested in the G1 phase of the cell cycle, and their growth suppression can be restored by treatment with decorin antisense oligodeoxynucleotides. These effects are independent of growth factors and are not due to either clonal selection or integration site of the decorin gene. These findings correlate well with the observation that decorin gene expression is markedly up-regulated during quiescence. Decorin thus appears to be one component of a negative loop that controls cell growth.

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The epithelial-specific integrin alpha 6 beta 4 is suprabasally expressed in benign skin tumors (papillomas) and is diffusely expressed in carcinomas associated with an increase in the proliferating compartment. Analysis of RNA samples by reverse transcriptase-PCR and DNA sequencing revealed that chemically or oncogenically induced papillomas (n = 8) expressed a single transcript of the alpha 6 subunit, identified as the alpha 6 A splice variant. In contrast, carcinomas (n = 13) expressed both alpha 6A and an alternatively spliced form, alpha 6B. Primary keratinocytes and a number of keratinocyte cell lines that vary in biological potential from normal skin, to benign papillomas, to well-differentiated slowly growing carcinomas exclusively expressed alpha 6A. However, I7, an oncogene-induced cell line that produces highly invasive carcinomas, expressed both alpha 6A and alpha 6B transcript and protein. The expression of alpha 6B in I7 cells was associated with increased attachment to a laminin matrix compared to cell lines exclusively expressing alpha 6A. Furthermore, introduction of an alpha 6B expression vector into a papilloma cell line expressing alpha 6A increased laminin attachment. When a papilloma cell line was converted to an invasive carcinoma by introduction of the v-fos oncogene, the malignant cells expressed both alpha 6A and alpha 6B, while the parent cell line and cells transduced with v-jun or c-myc, which retained the papilloma phenotype, expressed only alpha 6A. Comparative analysis of alpha 6B expression in cell lines and their derived tumors indicate that alpha 6B transcripts are more abundant in tumors than cell lines, and alpha 6B is expressed to a greater extent in poorly differentiated tumors. These results establish a link between malignant conversion and invasion of squamous tumor cells and the regulation of transcript processing of the alpha 6 beta 4 integrin.

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Several lines of evidence indicate that immunoglobulin-bound prolactin found in human serum is not a conventional complex between an anti-prolactin antibody and prolactin but a different type of association of prolactin with the Fab portion of IgG heavy chains. The complex of prolactin with IgG was purified from serum by anti-human prolactin affinity chromatography and was shown to contain close to 1 mole of N epsilon-(gamma-glutamyl)lysine crosslinks per mole of complex, a characteristic feature in structures crosslinked by transglutaminase. Interestingly, the complex caused a proliferation of cells from a subset of patients with chronic lymphocytic leukemia, while it was inactive in a cell proliferation prolactin bioassay. By contrast, human prolactin stimulated the proliferation of cells in the bioassay but had no effect on the complex-responsive cells from the patients. Competition studies with prolactin and free Fc fragment of IgG demonstrated a necessity for engaging both the prolactin and the immunoglobulin receptors for proliferation. More importantly, competition for the growth response by free prolactin and IgG suggests both possible reasons for the slow growth of this neoplasm as well as avenues for control of the disease.

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INTRODUÇÃO: A prótese biliar endoscópica é aceita em todo o mundo como a primeira escolha de tratamento paliativo na obstrução biliar maligna. Atualmente ainda persistem dois tipos de materiais utilizados em sua confecção: plástico e metal. Consequentemente, muitas dúvidas surgem quanto a qual deles é o mais benéfico para o paciente. Esta revisão reúne as informações disponíveis da mais alta qualidade sobre estes dois tipos de prótese, fornecendo informações em relação à disfunção, complicação, taxas de reintervenção, custos, sobrevida e tempo de permeabilidade; e pretende ajudar a lidar com a prática clínica nos dias de hoje. OBJETIVO: Analisar, através de metanálise, os benefícios de dois tipos de próteses na obstrução biliar maligna inoperável. MÉTODOS: Uma revisão sistemática de ensaios clínicos randomizados (RCT) foi conduzida, com a última atualização em março de 2015, utilizando EMBASE, CINAHL (EBSCO), Medline, Lilacs / Centro (BVS), Scopus, o CAPES (Brasil), e literatura cinzenta. As informações dos estudos selecionados foram extraídas tendo em vista seis desfechos: primariamente disfunção, taxas de reintervenção e complicações; e, secundariamente, custos, sobrevivência e tempo de permeabilidade. Os dados sobre as características dos participantes do RCT, critérios de inclusão e exclusão e tipos de próteses também foram extraídos. Os vieses foram avaliados principalmente através da escala de Jadad. Esta metanálise foi registrada no banco de dados PROSPERO pelo número CRD42014015078. A análise do risco absoluto dos resultados foi realizada utilizando o software RevMan 5, calculando as diferenças de risco (RD) de variáveis dicotômicas e média das diferenças (MD) de variáveis contínuas. Os dados sobre a RD e MD para cada desfecho primário foram calculados utilizando o teste de Mantel-Haenszel e a inconsistência foi avaliada com o teste Qui-quadrado (Chi2) e o método de Higgins (I2). A análise de sensibilidade foi realizada com a retirada de estudos discrepantes e a utilização do efeito aleatório. O teste t de Student foi utilizado para a comparação das médias aritméticas ponderadas, em relação aos desfechos secundários. RESULTADOS: Inicialmente foram identificados 3660 estudos; 3539 foram excluídos por título ou resumo, enquanto 121 estudos foram totalmente avaliados e foram excluídos, principalmente por não comparar próteses metálicas (SEMS) e próteses plásticas (PS), levando a treze RCT selecionados e 1133 indivíduos metanálise. A média de idade foi de 69,5 anos, e o câncer mais comum foi de via biliar (proximal) e pancreático (distal). O diâmetro de SEMS mais utilizado foi de 10 mm (30 Fr) e o diâmetro de PS mais utilizado foi de 10 Fr. Na metanálise, SEMS tiveram menor disfunção global em comparação com PS (21,6% versus 46,8% p < 0,00001) e menos reintervenções (21,6% versus 56,6% p < 0,00001), sem diferença nas complicações (13,7% versus 15,9% p = 0,16). Na análise secundária, a taxa média de sobrevida foi maior no grupo SEMS (182 contra 150 dias - p < 0,0001), com um período maior de permeabilidade (250 contra 124 dias - p < 0,0001) e um custo semelhante por paciente, embora menor no grupo SEMS (4.193,98 contra 4.728,65 Euros - p < 0,0985). CONCLUSÃO: SEMS estão associados com menor disfunção, menores taxas de reintervenção, melhor sobrevida e maior tempo de permeabilidade. Complicações e custos não apresentaram diferença

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PURPOSE: Malignant ascites is debilitating for patients with advanced cancer. As shown previously, tumour cell production of vascular endothelial growth factor might be a major cause of the formation of malignant ascites. Intraperitoneal bevacizumab could therefore be an option for symptom control in refractory ascites. PATIENTS AND METHODS: Patients with advanced gastrointestinal cancer and malignant ascites who had undergone paracentesis at least twice within the past 4 weeks were randomly assigned in a 2:1 ratio to intraperitoneal bevacizumab (400 mg absolute) or placebo after paracentesis. During the 8-week treatment period, a minimum interval of 14 d was kept between the applications of the study drug. Primary end-point was paracentesis-free survival (ParFS). RESULTS: Fifty-three patients (median age 63 years) were randomised. Forty-nine patients received at least one study drug application and qualified for the main analysis. The proportion of patients with at least one common toxicity criteria grade III-V event was similar with 20/33 (61%) on bevacizumab and 11/16 (69%) on placebo. Median ParFS was 14 d (95% confidence interval [CI]: 11-17) in the bevacizumab arm and 10.5 d (95% CI: 7-21) on placebo (hazard ratio 0.74, 95% CI: 0.40-1.37; P = 0.16). The longest paracentesis-free period was 19 d on bevacizumab (range 6-66 d) and 17.5 d in the placebo arm (range 4-42) (P = 0.85). Median overall survival was 64 d (95% CI: 45-103) on bevacizumab compared to 31.5 d (95% CI: 20-117) on placebo (P = 0.31). CONCLUSION: Intraperitoneal bevacizumab was well tolerated. Overall, treatment did not result in a significantly better symptom control of malignant ascites. However, patients defined by specific immune characteristics may benefit.

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Objective. To evaluate the association between nasal obstruction and (1) demographic factors, (2) medical history, (3) physical tests, and (4) nasal exam findings. Study Design. CASE SERIES: Methods. Chart review at a tertiary medical center. Results. Two hundred-forty consecutive patients (52.1 ± 17.5 years old, with a Nasal Obstruction Symptom Evaluation (NOSE) score of 32.0 ± 24.1) were included. Demographic factors and inferior turbinate sizes were not associated with NOSE score or Nasal Obstruction Visual Analog Scale (NO-VAS). A significant association was found between higher NOSE score on univariate analysis and positive history of nasal trauma (p = 0.0136), allergic rhinitis (p < 0.0001), use of nasal steroids (p = 0.0108), higher grade of external nasal deformity (p = 0.0149), higher internal nasal septal deviation grade (p = 0.0024), and narrow internal nasal valve angle (p < 0.0001). Multivariate analysis identified the following as independent predictors of high NOSE score: NO-VAS: ≥50 (Odds Ratio (OR) = 17.6 (95% CI 5.83-61.6), p < 0.0001), external nasal deformity: grades 2-4 (OR = 4.63 (95% CI 1.14-19.9), p = 0.0339), and allergic rhinitis: yes (OR = 5.5 (95% CI 1.77-18.7), p = 0.0041). Conclusion. Allergic rhinitis, NO-VAS score ≥ 50, and external nasal deformity (grades 2-4) were statistically significant independent predictors of high NOSE scores on multivariate analysis. Inferior turbinate size was not associated with NOSE scores or NO-VAS.

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Mode of access: Internet.

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Mode of access: Internet.

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"June 1, 1941."

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Chiefly tables.

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Between 1993 and 2001, 106 patients with esophageal cancer were reviewed at a multidisciplinary clinic and treated with palliative intent by chemoradiation therapy. This study assesses the palliative benefit on dysphagia and documents the toxicity of this treatment. The study population comprised 72 men and 34 women with a median age of 69 years. Patients were treated with a median radiation dose of 35 Gy in 15 fractions with a concurrent single course of 5 FU-based chemotherapy. Dysphagia was measured at the beginning and completion of treatment and at monthly intervals until death, using a modified DeMeester (4-point) score. Treatment was well tolerated, with only 5% of patients failing to complete therapy. The treatment-related mortality was 6%. The median survival for the study population was 7 months. The median baseline score at presentation was 2 (difficulty with soft food). Following treatment, 49% of patients were assessed as having a dysphagia score of 0 (no dysphagia). Seventy-eight per cent had an improvement of at least one grade in their dysphagia score after treatment. Only 14% of patients showed no improvement with treatment. Fifty-one per cent maintained improved swallowing until the time of last follow-up or death. This single-institution study shows that chemoradiation therapy administered for the palliation of malignant dysphagia is well tolerated and produces a sustainable normalization in swallowing for almost half of all patients.