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991.
Occupational exposure to polycyclic aromatic hydrocarbons (PAH) is associated with an increased risk of urothelial carcinoma (UC). FGFR3 is found mutated in about 70% of Ta tumors, which represent the major group at diagnosis. The influence of PAH on FGFR3 mutations and whether it is related to the emergence or shaping of these mutations is not yet known. We investigated the influence of occupational PAH on the frequency and spectrum of FGFR3 mutations. We included on 170 primary urothelial tumors from five hospitals from France. Patients (median age, 64 yr) were interviewed to gather data on occupational exposure to PAH, revealing 104 non‐ and possibly PAH exposed patients, 66 probably and definitely exposed patients. Tumors were classified as follows: 75 pTa, 52 pT1, and 43 ≥pT2. Tumor grades were as follows: 6 low malignant potential neoplasms (LMPN) and 41 low‐grade and 123 high‐grade carcinomas. The SnaPshot method was used to screen for the following FGFR3 mutations: R248C, S249C, G372C, Y375C, A393E, K652E, K652Q, K652M, and K652T. Occupational PAH exposure was not associated with a particular stage or grade of tumors. Thirty‐nine percent of the tumors harbored FGFR3 mutations. After adjustment for smoking, occupational exposure to PAH did not influence the frequency [OR, 1.10; 95% CI, 0.78–1.52], or spectrum of FGFR3 mutations. Occupational exposure to PAH influenced neither the frequency nor the spectrum of FGFR3 mutations and there was no direct relationship between these mutations and this occupational hazard. © 2009 Wiley‐Liss, Inc.  相似文献   
992.
Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP) is one of the most frequently applied initial treatments for indolent B-cell non-Hodgkin lymphoma (B-NHL); however, information on its long-term outcome is limited. Untreated patients in the concurrent arm (Arm C) received six R (375 mg/m(2) ) treatments, 2 days prior to each cycle of CHOP, and patients in the sequential arm (Arm S) received 6 weekly R (375 mg/m(2) ) treatments following six cycles of CHOP. Sixty-nine patients were randomized but two patients were withdrawn before receiving the protocol treatment. Sixty-five patients (94%) had follicular lymphoma, and 37 (55%) were at low risk, 23 (34%) at intermediate risk and seven (10%) at high risk according to the Follicular Lymphoma International Prognostic Index. We previously reported that the overall response rate (ORR) in Arm C and in Arm S was 94% and 97%, respectively. The median progression-free survival (PFS)/7-year PFS rate in Arm C, Arm S and all 67 assessable patients was 2.4 years/23% (95% confidence interval [CI], 9-40%), 3.8 years/41% (95% CI, 23-57%) and 2.8 years/32% (95% CI, 20-45%), respectively. There was no significant difference between the two arms (P = 0.107). The overall survival (OS) of the 67 patients was 95% at 7 years. In conclusion, R-CHOP is a highly effective initial treatment for untreated indolent B-NHL in terms of ORR and OS; however, its long-term PFS is not good enough either in concurrent or sequential combination, warranting further investigations on post-remission therapy.  相似文献   
993.
994.
AIM:To investigate insulin-like growth factor 2(IGF2)differentially methylated region(DMR)0 hypomethylation in relation to clinicopathological and molecular features in colorectal serrated lesions.METHODS:To accurately analyze the association between the histological types and molecular features of each type of serrated lesion,we consecutively collected1386 formalin-fixed paraffin-embedded tissue specimens that comprised all histological types[hyperplastic polyps(HPs,n=121),sessile serrated adenomas(SSAs,n=132),traditional serrated adenomas(TSAs,n=111),non-serrated adenomas(n=195),and colorectal cancers(n=827)].We evaluated the methylation levels of IGF2 DMR0 and long interspersed nucleotide element-1(LINE-1)in HPs(n=115),SSAs(n=120),SSAs with cytological dysplasia(n=10),TSAs(n=91),TSAs with high-grade dysplasia(HGD)(n=15),non-serrated adenomas(n=80),non-serrated adenomas with HGD(n=105),and CRCs(n=794).For the accurate quantification of the relative methylation levels(scale 0%-100%)of IGF2 DMR0 and LINE-1,we used bisulfite pyrosequencing method.Tumor specimens were analyzed for microsatellite instability,KRAS(codons 12 and 13),BRAF(V600E),and PIK3CA(exons 9and 20)mutations;MLH1 and MGMT methylation;and IGF2 expression by immunohistochemistry.RESULTS:The distribution of the IGF2 DMR0 methylation level in 351 serrated lesions and 185 non-serrated adenomas(with or without HGD)was as follows:mean61.7,median 62.5,SD 18.0,range 5.0-99.0,interquartile range 49.5-74.4.The IGF2 DMR0 methylation level was divided into quartiles(Q1≥74.5,Q2 62.6-74.4,Q3 49.6-62.5,Q4≤49.5)for further analysis.With regard to the histological type,the IGF2 DMR0 methylation levels of SSAs(mean±SD,73.1±12.3)were significantly higher than those of HPs(61.9±20.5),TSAs(61.6±19.6),and non-serrated adenomas(59.0±15.8)(P<0.0001).The IGF2 DMR0 methylation level was inversely correlated with the IGF2 expression level(r=-0.21,P=0.0051).IGF2 DMR0 hypomethylation was less frequently detected in SSAs compared with HPs,TSAs,and non-serrated adenomas(P<0.0001).Multivariate logistic regression analysis also showed that IGF2 DMR0 hypomethylation was inversely associated with SSAs(P<0.0001).The methylation levels of IGF2 DMR0 and LINE-1 in TSAs with HGD(50.2±18.7and 55.7±5.4,respectively)were significantly lower than those in TSAs(61.6±19.6 and 58.8±4.7,respectively)(IGF2 DMR0,P=0.038;LINE-1,P=0.024).CONCLUSION:IGF2 DMR0 hypomethylation may be an infrequent epigenetic alteration in the SSA pathway.Hypomethylation of IGF2 DMR0 and LINE-1 may play a role in TSA pathway progression.  相似文献   
995.
Retroperitoneal fibrosis is a rare disease characterized by the development of inflammation and fibrosis in the soft tissues of the retroperitoneum and other abdominal organs.Retroperitoneal fibrosis can be of 2 types:idiopathic and secondary.The recently advocated concept and diagnostic criteria of immunoglobulin G4(IgG4)-related disease,derived from research on autoimmune pancreatitis(AIP),has led to widespread recognition of retroperitoneal fibrosis as a condition caused by IgG4-related disease.We now know that previously diagnosed idiopathic retroperitoneal fibrosis includes IgG4-related disease;however,the actual prevalence is unclear.Conversely,some reports on AIP suggest that retroperitoneal fibrosis is concurrently found in about 10% of IgG4-related disease.Because retroperitoneal fibrosis has no specific symptoms,diagnosis is primarily based on diagnostic imaging(computed tomography and magnetic resonance imaging),which is also useful in evaluating the effect of therapy.Idiopathic retroperitoneal fibrosis can occur at different times with other lesions of IgG4-related disease including AIP.Thus,the IgG4 assay is recommended to diagnose idiopathic retroperitoneal fibrosis.High serum IgG4 levels should be treated and monitored as a symptom of IgG4-related disease.The first line of treatment for retroperitoneal fibrosis is steroid therapy regardless of its cause.For patients with concurrent AIP,i.e.,IgG4-related retroperitoneal fibrosis,the starting dose of steroid is usually 30-40 mg/d.The response to steroid therapy is generally favorable.In most cases,the pancreatic lesion and retroperitoneal fibrosis improve after the initial treatment.However,the epidemiology,treatment for recurring retroperitoneal fibrosis,and long-term prognosis are still largely unknown.Further analysis of such cases and research are necessary.  相似文献   
996.
AIM: To clarify the efficacy and safety of an endoscopic approach through the minor papilla for the management of pancreatic diseases.METHODS: This study included 44 endoscopic retrograde cholangiopancreatography (ERCP) procedures performed in 34 patients using a minor papilla approach between April 2007 and March 2012. We retrospectively evaluated the clinical profiles of the patients, the endoscopic interventions, short-term outcomes, and complications.RESULTS: Of 44 ERCPs, 26 were diagnostic ERCP, and 18 were therapeutic ERCP. The most common cause of difficult access to the main pancreatic duct through the major papilla was pancreas divisum followed by distortion of Wirsung’s duct. The overall success rate of minor papilla cannulation was 80% (35/44), which was significantly improved by wire-guided cannulation (P = 0.04). Endoscopic minor papillotomy (EMP) was performed in 17 of 34 patients (50%) using a needle-knife (13/17) or a pull-type papillotome (4/17). EMP with pancreatic stent placement, which was the main therapeutic option for patients with chronic pancreatitis, recurrent acute pancreatitis, and pancreatic pseudocyst, resulted in short-term clinical improvement in 83% of patients. Mild post-ERCP pancreatitis occurred as an early complication in 2 cases (4.5%).CONCLUSION: The endoscopic minor papilla approach is technically feasible, safe, and effective when the procedure is performed in a high-volume referral center by experienced endoscopists.  相似文献   
997.
998.
999.
17α-Hydroxylase deficiency is rare autosomal recessive disorder that manifested by hypertension, hypokalemia, delayed sexual development, primary amenorrhea and infertility. The information regarding infertility care and conception in women with this disorder are extremely limited. We report a 24-year-old Japanese woman with primary amenorrhea who was diagnosed as partial 17α-hydroxylase deficiency caused by homozygous 3?bp deletion in exon 1 of 17α-hydroxylase gene. In vitro fertilization with controlled ovarian stimulation was carried out and all viable embryo were frozen. During ovarian stimulation, serum progesterone levels were markedly elevated, and endometrial growth was impaired. Utilizing frozen-thaw embryo transfer under hormonal replacement (glucocorticoid, estradiol and progesterone), she had successfully given two consecutive live birth. Women with 17α-hydroxylase deficiency with residual ovarian reserve can afford reproductive success by appropriate diagnosis and treatment by assisted reproductive technology.  相似文献   
1000.
PURPOSE: To assess effects of antiglaucoma drugs on refractive outcomes in eyes with myopic regression after laser in situ keratomileusis (LASIK). DESIGN: Prospective, nonrandomized clinical trial. METHODS: We examined 27 eyes with mean myopic regression +/- standard deviation of -1.26 +/- 0.48 diopters (D; range, -0.50 to -2.25 D) after LASIK. Nipradilol 2.5% was administered topically twice daily to these regressive eyes. We obtained the refraction (spherical equivalent, astigmatism), intraocular pressure (IOP) measurements, pachymetry, geometry, and refractive power of the cornea before and three months after treatment. RESULTS: Mean manifest refraction was improved significantly from -1.02 +/- 0.52 D to -0.44 +/- 0.39 D (P < .001). However, mean manifest astigmatism was changed from -0.55 +/- 0.30 D to -0.49 +/- 0.22 D, but the difference was not significant (P = .23). The IOP was decreased significantly from 11.4 +/- 2.4 mm Hg to 9.4 +/- 1.3 mm Hg (P < .001). Central corneal thickness was not changed significantly from 505.2 +/- 39.3 microm to 503.6 +/- 38.7 microm (P = .61). The posterior corneal surface was shifted posteriorly by 9.1 +/- 8.2 microm, and the total refractive power of the cornea was decreased significantly, by 0.63 +/- 0.62 D (P < .001), at three months after application. CONCLUSIONS: The preliminary data show that antiglaucoma drugs are effective for the reduction of the refractive regression, especially of the spherical errors, after LASIK. It is suggested that backward movement of the cornea may occur, possibly flattening the corneal curvature by lowering the IOP. Reduction of the IOP may contribute to improving regression after keratorefractive surgery.  相似文献   
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