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31.
Heritable somatic methylation and inactivation of MSH2 in families with Lynch syndrome due to deletion of the 3' exons of TACSTD1
Ligtenberg et al. (2009)
Nature Genetics 41: 112–117  相似文献   
32.
PURPOSE: To evaluate daily physical-rest activities in cancer patients losing weight in relation to disease progression. EXPERIMENTAL DESIGN: Physical activity-rest rhythms were measured (ActiGraph, armband sensor from BodyMedia) in relation to body composition (dual-energy X-ray absorptiometry), energy metabolism, exercise capacity (walking test), and self-scored quality of life (SF-36, Hospital Anxiety and Depression Scale) in weight-losing outpatients with systemic cancer (71 +/- 2 years, n = 53). Well-nourished, age-matched, and previously hospitalized non-cancer patients served as controls (74 +/- 4 years, n = 8). Middle-aged healthy individuals were used as reference subjects (49 +/- 5 years, n = 23). RESULTS: Quality of life was globally reduced in patients with cancer (P < 0.01), accompanied by significantly reduced spontaneous physical activity during both weekdays and weekends compared with reference subjects (P < 0.01). Spontaneous physical activity declined over time during follow-up in patients with cancer (P < 0.05). However, overall physical activity and the extent of sleep and bed-rest activities did not differ between patients with cancer and age-matched non-cancer patients. Spontaneous physical activity correlated weakly with maximum exercise capacity in univariate analysis (r = 0.41, P < 0.01). Multivariate analysis showed that spontaneous physical activity was related to weight loss, blood hemoglobin concentration, C-reactive protein, and to subjectively scored items of physical functioning and bodily pain (SF-36; P < 0.05-0.004). Anxiety and depression were not related to spontaneous physical activity. Patient survival was predicted only by weight loss and serum albumin levels (P < 0.01), although there was no such prediction for spontaneous physical activity. CONCLUSIONS: Daily physical-rest activities represent variables which probably reflect complex mental physiologic and metabolic interactions. Thus, activity-rest monitoring provides a new dimension in the evaluation of medical and drug interventions during palliative treatment of patients with cancer.  相似文献   
33.
2002年5月1日颁布实施的《中华人民共和国职业病防治法》是规范职业卫生技术服务行为的法律依据。这是职业卫生技术服务工作走上规范化、标准化、法制化的根本保障,是职业卫生技术服务机构参与市场竞争、提高服务质量、促进自身发展的必由之路,也是企业自主选择职业卫生技术服务机构、提高职业危害防治水平、促进经济发展的关键所在。4年多来,我市各级各类职业卫生技术服务机构的发展极不平衡,仪器设备配备水平、人员能力素质与我省同类地区相比也有较大差距。为了解我市职业卫生技术服务机构现状,我们进行了此项调查。  相似文献   
34.
We investigated if orally administered bifidobacteria and/or lactobacilli could be cultured from faeces of infants after antibiotic treatment, when these bacterial species are usually absent. Lyophilized Bifidobacterium longum, strain BB-536, B. breve, strain BB-576, or Lactobacillus acidophilus, strain LAC-343, were used. Doses of 3 x 10(9) cells of one strain, or a mixture of all three strains 3 x 10(9) cells each were fed three times daily at mealtimes to 11 infants aged 0-8 weeks. Treatment was started the first day after antibiotic treatment and was continued for 5 days. The bacterial species were isolated in 9 of 11, 7 of 10 and 2 of 9 specimens obtained on the last day of bifidobacteria or lactobacilli administration, 5 and 15 days thereafter, respectively. No side effects were noted.  相似文献   
35.
We present a patient with surgical stage I endometrial cancer who experienced laparotomy wound recurrence 4 years after primary treatment. She was treated successfully by complete surgical resection of recurrent tumors and chemotherapy. A 62-year-old white female with laparotomy wound recurrence of endometrial carcinoma with small-bowel involvement and concomitant subcutaneous metastasis in the abdominal wall underwent complete surgical resection of metastatic tumors followed by six cycles of chemotherapy consisting of paclitaxel (175 mg/m2) and carboplatin (area under the curve 5). Since 24 months after resection of recurrence, she has no evidence of disease recurrence. Endometrial carcinoma with laparotomy wound recurrences, especially those with concomitant metastases, can be successfully treated by complete surgical resection followed by chemotherapy consisting of paclitaxel and carboplatin.  相似文献   
36.
The sialyl-Lex determinant (NeuAc alpha 2-->3Gal beta 1-->4[Fuc alpha- 1-->3]GlcNAc) has been identified as a major ligand in the selectin- mediated adhesion of neutrophils and monocytes to activated endothelium or platelets. This carbohydrate epitope is formed by the sequential action of alpha 3-sialyltransferase and alpha 3-fucosyltransferase on N- acetyllactosamine (Gal beta 1-->4GlcNAc) disaccharide termini of glycoconjugates. We have addressed the role of the human myeloid alpha 3-fucosyltransferase in the expression of this epitope at the leucocyte surface by determining its activity in human-mouse leukemic cell hybrids (WEGLI), normal human granulocytes and chronic myeloid leukemia (CML) cells using sialylated and desialylated glycoproteins and oligosaccharides as acceptor substrates. In contrast to what has been reported for the myeloid-type enzyme, we found that the alpha 3- fucosyltransferase of the cells studied can use sialylated acceptors be it that the activity is several times lower than with asialo- substrates. Characterization of the product obtained with a sialylated oligosaccharide indicated that the enzyme can catalyze the formation of the sialyl-Le(x) structure. Flow cytometry of the WEGLI cells using a sialyl-Le(x)-specific monoclonal antibody (MoAb) showed that these cells indeed express sialyl-Lex at their surface, provided that they contain human chromosome 11. Earlier the presence of this chromosome had been correlated with the expression of alpha 3-fucosyltransferase activity. In addition to sialyl-Le(x), WEGLI cells containing chromosome 11 showed high-expression levels of related structures recognized by antibodies VIM-2 and VIM-8, suggesting that fucose addition can occur at both distal and proximal GlcNAc residues in poly- N-acetyl-lactosaminoglycan sequences. Based on the human chromosome contents it could be ruled out that the alpha 3-fucosyltransferase of WEGLI cells is a Lewis-type alpha 3/4- or plasma-type alpha 3- fucosyltransferase, the genes of which have been mapped to chromosome 19. It is concluded that the enzyme studied is of the myeloid-type and indeed is involved in the synthesis of sialyl-Le(x) (and also VIM-2 and VIM-8 structures) in leukocytes provided that its expression is at a sufficiently high level.  相似文献   
37.
38.
The role of p53 mutations in disease progression and survival of colorectal cancer is unclear, since numerous studies have reported different conclusions. However, few reports, if any, have evaluated disease progression and survival in relationship to 'functional' and 'non-functional' p53 status defined by genetic and molecular indications. Malignant colorectal tumors, from 72 unselected patients who underwent primary and potentially curative elective tumor resections, were either classified as p53 functional (p53+/+, p53+/-) or non-functional (p53-/-) based on DNA sequence analysis of all p53 exons, including determination of allelic imbalance of p53 (LOH), according to four DNA markers; 2 within the coding gene and two markers in the immediate flanking regions of p53. Tumor frequency of microsatellite instability was also analyzed according to Dukes' A-D stages. Dukes' staging predicted survival as expected, while the conceptual p53 status, functional p53 vs non-functional p53, did not clear-cut predict disease specific survival. p53 mutations alone or allelic imbalance inside the reading frame of the gene were unpredictive of survival, while allelic imbalance downstream of p53 predicted reduced survival (p < 0.05). The present study demonstrates that base mutations in combination with allelic imbalance within the reading frame of p53 do not predict survival or progression of colorectal cancer, while allelic imbalance upstream coding parts of the gene predicted disease-specific survival in univariate analysis. Thus, structural alterations within the gene seem less important than alterations in regions with potential control elements.  相似文献   
39.
Earlier observations on cyclo-oxygenase inhibitors (NSAIDs) restricting tumor growth were re-evaluated by comparing the effects of non-selective, preferential selective and selective derivatives of COX-inhibitors on tumor growth in mouse models with either prostaglandin-sensitive (MCG-101, human tumors) and -insensitive transplants (K1735-M2). Tumor growth, with and without provision of a classical cyclo-oxygenase inhibitor (indomethacin), was related to tumor content of COX-1/COX-2 protein as well as to EP1-EP4 and prostacyclin receptor expression. Mouse serum amyloid protein (SAP) was measured as an indicator of systemic inflammation, which relates to pro-inflammatory cytokines. Indomethacin inhibited tumor growth and prolonged the survival of mice bearing MCG-101 tumors, which display a high production of PGE2, while K1735-M2 tumors with insignificant amounts of PGE2 did not respond to indomethacin at all. However, the effects of various NSAIDs on tumor growth were highly variable in combination with the fact that most preferential selective and selective COX-2 inhibitors attenuated poorly systemic inflammation evaluated by plasma concentrations of mouse SAP. The ability of NSAIDs to attenuate tumor growth was not related to the tumor content of COX-2 protein as expected. Multivariate analysis suggests that significant COX-inhibition of tumor growth may be related to tumor expression of subtype EP2, EP3 (p<0.005) and perhaps EP4 (p<0.09) in complex interplay. The extent of tumor growth inhibition by COX-inhibitors is not simply related to drug specificity on COX-1 or COX-2 pathways. Such effects may instead be related to tumor expression of prostanoid receptors in tumor tissue.  相似文献   
40.
It is well established that prostanoids are essential for local inflammation including cell proliferation and apoptosis. Accordingly, prostaglandin E2 (PGE(2)) is a critical factor in wound healing, tumor invasiveness and progression. Therefore, the aim of the present work was to evaluate effects by PGE(2) on tumor vascular density at early onset of tumor growth where hypoxia is limited. Wild-type mice (C57Bl, C3H/HeN) bearing either MCG-101 tumors or a malignant melanoma (K1735-M2) with either high or insignificant PGE(2) production and subsequently different in sensitivity to cyclooxygenase (COX) inhibition were used. Tumor angiogenesis was estimated by intravital microscopy and immune histochemical analysis in wild type and EP(1) or EP(3) subtype receptor knockout mice (C57Bl). Both MCG-101 and K1735-M2 tumor cells stimulated early outgrowth of tumor vessels in proportion to intrinsic growth rate of tumor cells. Indomethacin had no effects on tumor growth or tumor related vascular area in K1735-M2 bearing mice. By contrast, indomethacin decreased tumor cell proliferation and increased apoptosis in MCG-101 tumors with subsequent adaptation in tumor vascular density. Effects of indomethacin on early growth of MCG-101 tumors were not related to tumor content of bFGF protein, while our earlier studies on long-term tumor growth have shown decreased mRNA levels of bFGF during indomethacin treatment. Early onset of tumor growth was significantly promoted in EP(3)- but not in EP(1)-knockouts, although long-term tumor growth is attenuated in EP(1)-knockouts as reported elsewhere. Our results demonstrate that tumor production of PGE(2) promotes primarily net growth of tumor cells with subsequent adaptations in development of the tumor vasculature. Therefore, it is likely that angiogenesis is not a limiting step at the early onset of tumor growth.  相似文献   
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