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71.
72.
Risk of malignancy in patients with celiac disease   总被引:15,自引:0,他引:15  
PURPOSE: Studies from Europe have demonstrated an increased risk of malignancy, especially non-Hodgkin's lymphoma, in patients with celiac disease. However, there are no data on the risk for similar patients in the United States. Our aim was to estimate the risk of malignancy in a cohort of patients with celiac disease compared with the general U.S. population and to determine if a gluten-free diet is protective. METHODS: Patients with celiac disease seen between July 1981 and January 2000 at a referral center were included. Standardized morbidity ratios (SMRs) (ratio of observed to expected) and corresponding 95% confidence intervals (CI) were calculated, using data from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program. RESULTS: Forty-three (11%) of 381 celiac disease patients had a diagnosis of cancer; 9 were after the diagnosis of celiac disease, 7 were simultaneous (during same month or admission), and 27 were before the diagnosis. The standardized morbidity ratio for all cancers combined was 1.5 (95% CI: 0.3 to 7.5), with significantly increased values for small bowel cancer (SMR = 34; 95% CI: 24 to 42), esophageal cancer (SMR = 12; 95% CI: 6.5 to 21), non-Hodgkin's lymphoma (SMR = 9.1; 95% CI: 4.7 to 13), and melanoma (SMR = 5.0; 95% CI: 2.1 to 12). Following the diagnosis of celiac disease, patients were at increased risk of non-Hodgkin's lymphoma only (SMR = 6.2; 95% CI: 2.9 to 14), despite adherence to a gluten-free diet. The non-Hodgkin's lymphoma included both T-cell and B-cell types and occurred in both gastrointestinal (n = 5) and extraintestinal sites (n = 4). CONCLUSION: In this cohort of patients with celiac disease, we observed increased risks of small intestinal adenocarcinoma, esophageal cancer, melanoma, and non-Hodgkin's lymphoma. The risk of non-Hodgkin's lymphoma persisted despite a gluten-free diet.  相似文献   
73.
Current data overwhelmingly document the existence of a worldwide asthma epidemic, although individual studies remain controversial. The epidemic is thought to involve primarily persons with allergic asthma, and many diverse theories, based on an immunopathologic understanding of disease, have recently emerged to explain this involvement. In the context of recent insights into the immune basis of experimental asthma, we discuss in this review the leading asthma epidemic theories, including a new theory based on inhaled environmental proteases. Although no single theory may yet be fully embraced, there exists substantial hope that a unifying mechanism for the epidemic will be revealed through additional research.  相似文献   
74.
E2F-1 and cyclin B are important regulators of the cell cycle, and their expressionand degradation are tightly regulated. Proteolysis of both molecules is mediated by the ubiquitin degradation pathway involving the activation of specific E3 ubiquitin ligases. Treatment of prostate carcinoma cells with the novel retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437/AHPN) results in the enhanced expression of E2F-1 and rapid degradation of cyclin B in the absence of the modulation of mRNA levels; this is accompanied by the S phase arrest of the cells and subsequent apoptosis. The elevated level of E2F-1 is because of the enhanced stability of the molecule, as indicated by pulse-labeling studies, demonstrating a prolonged half-life. The enhanced E2F-1 stability is associated with the concomitant acetylation of E2F-1, the disassociation of E2F-1 from the E2F-1 E3 ligase p45(SKP2), and decreased E2F-1 ubiquitination, suggesting CD437 inhibition of E-3 E2F-1 ligase activity. Exposure of the cells to CD437 also results in the enhanced association of the cyclin B E3 ligase APC with cyclin B and the rapid proteolysis of cyclin B. The CD437-enhanced proteolysis of cyclin B is blocked in the presence of the ubiquitin proteolysis inhibitor N-acetyl-leu-leu-norleu-al. Thus, CD437 modulates the expression of E2F-1 and cyclin B through the simultaneous stimulation and inhibition of the cyclin B and E2F-1 E3 ligases, respectively.  相似文献   
75.
BRAF and RAS mutations in human lung cancer and melanoma   总被引:22,自引:0,他引:22  
BRAF encodes a RAS-regulated kinase that mediates cell growth and malignant transformation kinase pathway activation. Recently, we have identified activating BRAF mutations in 66% of melanomas and a smaller percentage of many other human cancers. To determine whether BRAF mutations account for the MAP kinase pathway activation common in non-small cell lung carcinomas (NSCLCs) and to extend the initial findings in melanoma, we screened DNA from 179 NSCLCs and 35 melanomas for BRAF mutations (exons 11 and 15). We identified BRAF mutations in 5 NSCLCs (3%; one V599 and four non-V599) and 22 melanomas (63%; 21 V599 and 1 non-V599). Three BRAF mutations identified in this study are novel, altering residues important in AKT-mediated BRAF phosphorylation and suggesting that disruption of AKT-induced BRAF inhibition can play a role in malignant transformation. To our knowledge, this is the first report of mutations documenting this interaction in human cancers. Although >90% of BRAF mutations in melanoma involve codon 599 (57 of 60), 8 of 9 BRAF mutations reported to date in NSCLC are non-V599 (89%; P < 10(-7)), strongly suggesting that BRAF mutations in NSCLC are qualitatively different from those in melanoma; thus, there may be therapeutic differences between lung cancer and melanoma in response to RAF inhibitors. Although uncommon, BRAF mutations in human lung cancers may identify a subset of tumors sensitive to targeted therapy.  相似文献   
76.
77.
We present the results of a modified minimally invasive surgical technique in the management of ganglia of the wrist. Twenty six ganglia have been treated by this method. The patient satisfaction for the procedure was 92.3%. An average of 2 days were lost off work consequent to the procedure. The use of this technique has resulted in a 77.9% mean resolution in size with 50% of the patients showing complete resolution. There were no recurrences noted in the 2 year follow-up.  相似文献   
78.
OBJECTIVE: To determine if reducing missed therapy sessions by patients requiring hemodialysis will reduce the length of stay (LOS) and improve the efficiency of care in an inpatient rehabilitation unit. DESIGN: Retrospective study. SETTING: Inpatient rehabilitation unit at a university medical center. PARTICIPANTS: All patients discharged from the Albany Medical Center rehabilitation unit between January 1, 2003, and June 30, 2004. The total number of patients was 955, 40 of whom required hemodialysis. INTERVENTION: On January 1, 2003, Albany Medical Center began providing hemodialysis in the late afternoon, allowing patients to complete a full 3-hour program without missing therapy sessions to attend dialysis. We compared the outcomes of 915 patients who did not require hemodialysis with the outcomes of 40 patients who required hemodialysis. We also compared the outcomes of patients treated on the rehabilitation unit in 2003-2004 to the outcomes of patients treated on the rehabilitation unit before dialysis was available at times that did not conflict with therapy (calendar year 2001). MAIN OUTCOME MEASURES: LOS, improvement on the FIM instrument, and FIM efficiency score. RESULTS: The LOS of the hemodialysis patients changed from 16.0 in 2001 to 12.1 in 2003-2004 (P<.05), and the FIM efficiency score of the hemodialysis patients improved from 1.8 in 2001 to 2.9 in 2003-2004 (P<.05). The FIM efficiency score of the nondialysis group in 2003-2004 was 4.0. This was significantly greater (P<.05) than that of dialysis patients in 2003-2004. CONCLUSIONS: A program to reduce conflicts between medical treatments such as hemodialysis and therapy sessions may result in reduced LOS and improved efficiency on an inpatient rehabilitation unit.  相似文献   
79.
Bhanot A  Kaushal R  Bhan R  Gupta PN  Gupta RK  Bahadur R 《Injury》2004,35(12):219-1344
Fracture of posterior process of talus is quite rare, but is associated with significant morbidity as it involves two articular surfaces. We report two such cases in which open reduction and internal fixation were done with good functional results. One of the cases had a concomitant medial malleolus fracture which to the best of our knowledge has not been reported so far.  相似文献   
80.
To determine whether cancer risk is related to histopathological features of preneoplastic aberrant crypt foci (ACF), gene expression analysis was performed on ACF from two mouse strains with differing tumor sensitivity to the colonotropic carcinogen, azoxymethane. ACF from sensitive A/J mice were considered at high risk, whereas ACF from resistant AKR/J mice were considered at low risk for tumorigenesis. A/J and AKR/J mice received weekly injections of azoxymethane (10 mg/kg body weight), and frozen colon sections were prepared 6 weeks later. Immunohistochemistry was performed using biomarkers associated with colon cancer, including adenomatous polyposis coli, beta-catenin, p53, c-myc, cyclin D1, and proliferating cell nuclear antigen. Hyperplastic ACF, dysplastic ACF, microadenomas, adjacent normal-appearing epithelium, and vehicle-treated colons were laser captured, and RNA was linearly amplified (LCM-LA) and subjected to cDNA microarray-based expression analysis. Patterns of gene expression were identified using adaptive centroid algorithm. ACF from low- and high-risk colons were not discriminated by immunohistochemistry, with the exception of membrane staining of beta-catenin. To develop genetic signatures that predict cancer risk, LCM-LA RNA from ACF was hybridized to cDNA arrays. Of 4896 interrogated genes, 220 clustered into six broad clusters. A total of 226 and 202 genes was consistently altered in lesions from A/J and AKR/J mice, respectively. Although many alterations were common to both strains, expression profiles stratified high- and low- risk lesions. These data demonstrate that ACF with distinct tumorigenic potential have distinguishing molecular features. In addition to providing insight into colon cancer promotion, our data identify potential biomarkers for determining colon cancer risk in humans.  相似文献   
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