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Cadherin-17 (CDH17), also called liver–intestine cadherin, is a structurally unique member of the cadherin superfamily. Our serial analysis of gene expression demonstrated that CDH17 was one of the most up-regulated genes in advanced gastric carcinomas. CDH17 expression is known to be regulated by Cdx2. In the present study, we examined the expression of CDH17 in primary gastric carcinoma tissues by immunohistochemistry, and analyzed the correlation of CDH17 expression with clinicopathological characteristics and patients prognosis. CDH17 expression was detected in 63/94 (67%) of gastric adenocarcinomas in addition to intestinal metaplasia. The expression of CDH17 tended to be associated with intestinal type carcinoma, and carcinomas with CDH17 expression was significantly more frequent in advanced stage cases (80%) than in early stage (53%). The prognosis of patients with positive CDH17 expression was significantly poorer than that of the negative cases (P=0.0314). However, multivariate analysis revealed that CDH17 was not an independent prognostic factor. Six of seven cases that showed positive expression of Cdx2 simultaneously expressed CDH17 protein. These results suggested that the expression of CDH17 was characteristic of the advanced gastric carcinoma that is associated with poor prognosis.  相似文献   
3.
目的探讨钙粘蛋白23基因(CDH23)多态性与噪声性听力损失之间的关系。方法采用横断面流行病学研究方法,对194名噪声暴露作业工人进行调查和听力测试,按听力学评价的结果将其分为听力损失组和听力正常组;用多聚酶链反应-限制性片断长度多态性(PCRRFLP)方法检测其CDH23基因上4个单核苷酸位点的多态性。结果CDH23基因的rs1227049和rs1227051两个位点的基因型分布及其等位基因频率在93名噪声性听力损失与101名听力正常工人之间差异无显著性(P>0.05);而rs3802711位点和第七外显子的末位单核苷酸位点的基因型分布及其等位基因频率在两组之间差异均有极显著性(P<0.01)。用多元Logistic回归分析对两组间年龄、性别、吸烟状况、爆震史和累积噪声暴露量等因素进行校正后,发现rs1227049位点的CC基因型与GG基因型相比噪声性听力损失的危险度显著升高,调整OR值为3.865(95%可信区间为1.076~13.886);rs3802711位点的TT基因型与CT基因型相比噪声性听力损失的危险度有极显著性升高,调整OR值为6.088(95%可信区间为2.485~14.917);第七外显子的末位单核苷酸位点的GG基因型与AG基因型相比噪声性听力损失的危险度也有极显著性升高,调整OR值为5.769(95%可信区间为2.745~12.121)。结论钙粘蛋白23基因多态性可能在噪声性听力损失的发病过程中起重要作用,携带rs1227049CC基因型、rs3802721TT基因型和第七外显子末位单核苷酸位点GG基因型的个体对噪声性听力损失更为易感。  相似文献   
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Using exome sequencing we identify a heterozygous nonsense mutation in ZFPM2 as a cause of familial isolated congenital diaphragmatic hernia in 2 affected siblings. This mutation displays variable phenotypic expression being present in a third sibling with a mild diaphragmatic eventration and a cardiovascular malformation. The same variant is seen in 2 additional family members, both of whom are asymptomatic, thus highlighting that ZFPM2 haploinsufficiency is associated with reduced penetrance. Our finding adds further evidence for ZFPM2 having a role in diaphragm and cardiovascular development.  相似文献   
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Next-generation mate-pair sequencing (MPS) has revealed that many constitutional complex chromosomal rearrangements (CCRs) are associated with local shattering of chromosomal regions (chromothripsis). Although MPS promises to identify the molecular basis of the abnormal phenotypes associated with many CCRs, none of the reported mate-pair sequenced complex rearrangements have been simultaneously studied with state-of-the art molecular cytogenetic techniques. Here, we studied chromothripsis-associated CCR involving chromosomes 2, 5 and 7, associated with global developmental and psychomotor delay and severe speech disorder. We identified three truncated genes: CDH12, DGKB and FOXP2, confirming the role of FOXP2 in severe speech disorder, and suggestive roles of CDH12 and/or DGKB for the global developmental and psychomotor delay. Our study confirmes the power of MPS for detecting breakpoints and truncated genes at near nucleotide resolution in chromothripsis. However, only by combining MPS data with conventional G-banding and extensive fluorescence in situ hybridizations could we delineate the precise structure of the derivative chromosomes.  相似文献   
8.

Purpose

To determine developmental outcomes and associated factors in patients with congenital diaphragmatic hernia (CDH) at 2 years of age.

Methods

This is a multicenter prospective study of a CDH birth cohort. Clinical and socioeconomic data were collected. Bayley Scales of Infant Development (BSID-III) and Vineland Adaptive Behavior Scales (VABS-II) were performed at 2 years of age.

Results

BSID-III and VABS-II assessments were completed on 48 and 49 children, respectively. The BSID-III mean cognitive, language, and motor scores were significantly below the norm mean with average scores of 93 ± 15, 95 ± 16, and 95 ± 11. Ten percent (5/47) scored more than 2 standard deviations below the norm on one or more domains. VABS-II scores were similar to BSID-III scores with mean communication, daily living skills, social, motor, adaptive behavior scores of 97 ± 14, 94 ± 16, 93 ± 13, 97 ± 10, and 94 ± 14. For the BSID-III, supplemental oxygen at 28 days, a prenatal diagnosis, need for extracorporeal membrane oxygenation (ECMO) and exclusive tube feeds at time of discharge were associated with lower scores. At 2 years of age, history of hospital readmission and need for tube feeds were associated with lower scores. Lower socioeconomic status correlated with lower developmental scores when adjusted for significant health factors.

Conclusion

CDH patients on average have lower developmental scores at 2 years of age compared to the norm. A need for ECMO, oxygen at 28 days of life, ongoing health issues and lower socioeconomic status are factors associated with developmental delays.  相似文献   
9.
AIM: To explore germline hypermethylation of the tumor suppressor genes MLH1, CDH1 and P16INK4a in suspected cases of hereditary gastric cancer (GC).METHODS: A group of 140 Chinese GC patients in whom the primary cancer had developed before the age of 60 or who had a familial history of cancer were screened for germline hypermethylation of the MLH1, CDH1 and P16INK4a tumor suppressor genes. Genomic DNA was extracted from peripheral blood leukocytes and modified by sodium bisulfite. The treated DNA was then subjected to bisulfite DNA sequencing for a specific region of the MLH1 promoter. The methylation status of CDH1 or P16INK4a was assayed using methylation-specific PCR. Clonal bisulfite allelic sequencing in positive samples was performed to obtain a comprehensive analysis of the CpG island methylation status of these promoter regions.RESULTS: Methylation of the MLH1 gene promoter was detected in the peripheral blood DNA of only 1/140 (0.7%) of the GC patient group. However, this methylation pattern was mosaic rather than the allelic pattern which has previously been reported for MLH1 in hereditary non-polyposis colorectal cancer (HNPCC) patients. We found that 10% of the MLH1 alleles in the peripheral blood DNA of this patient were methylated, consistent with 20% of cells having one methylated allele. No germline promoter methylation of the CDH1 or P16INK4a genes was detected.CONCLUSION: Mosaic germline epimutation of the MLH1 gene is present in suspected hereditary GC patients in China but at a very low level. Germline epimutation of the CDH1 or P16INK4a gene is not a frequent event.  相似文献   
10.
Mutations in the CDH23 gene are known to be responsible for both Usher syndrome type ID (USH1D) and non-syndromic hearing loss (DFNB12), and the molecular confirmation of the CDH23 gene has become important in the diagnosis of these conditions. The present study was performed to find whether the CDH23 mutations are also responsible for non-syndromic hearing loss in patients in the Japanese population. A total of 51 sequence variants were found in 64 Japanese probands with non-syndromic sensorineural hearing impairment from autosomal recessive families. Among them, at least four missense mutations in six patients from five families were confirmed to be responsible for deafness by segregation study. All mutations detected were missense mutations, corroborating the previous reports regarding DFNB12. The present data confirmed that CDH23 mutations are frequently found and significantly responsible in Japanese. Interestingly, the CDH23 mutation spectrum in Japanese is very different from that found in Caucasians. This Japanese spectrum may be representative of those in Eastern Asian populations and its elucidation is expected to facilitate the molecular diagnosis of DFNB12 and USH1D.  相似文献   
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