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91.
Despite evidence of a substantial genetic component, the genetic factors that underlie longevity in humans remain to be identified. Previous genome-wide linkage and association studies have not found strong evidence for the contribution of common variants besides the APOE gene, suggesting the role of rare variants in human longevity. To discover rare variants that might contribute to longevity, we selected 988 candidate genes and performed a pilot study to identify novel non-synonymous variants in 6 Ashkenazi Jewish centenarians older than 105. Our candidate genes act in pathways implicated in aging and longevity, including neurodegeneration, cognitive function, lipid metabolism, DNA repair, and genome maintenance. By implementing custom-designed Agilent SureSelect target capture and next-generation sequencing, we discovered a total of 89 novel non-synonymous SNPs (nsSNPs) and validated 51 nsSNPs by iPLEX MassArray assays. Genotyping analysis of these novel SNPs in 410 Ashkenazi Jewish controls and 390 centenarians showed significant enrichment (5.3 fold, = 0.02) of the p.Y318C variant in PMS2 and significant depletion (7.5 fold, = 0.04) of the p.V465A variant in GABRR3 in centenarians compared to controls. Our study presents the potential of targeted next-generation sequencing for discovery of rare but functional genetic variation which may lead to exceptional longevity in humans.  相似文献   
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93.

Purpose

To investigate the ultrasonographic (US) features of anaplastic thyroid cancer (ATC) and the diagnostic performance of US-guided fine needle aspiration biopsy (FNAB) therein.

Materials and Methods

Eighteen cases of ATC diagnosed between January 2001 and May 2011 were included. FNAB was performed in all cases. Initial FNAB results were divided into three groups: 1) the cytological ATC group, cytological diagnosis of ATC; 2) the underestimated group, cytological diagnoses of malignancy other than ATC; and 3) the false negative group, cytological diagnoses of atypical, benign and non-diagnostic lesions. We retrospectively reviewed US findings and compared treatment modalities between each group.

Results

Among the 18 patients, there were nine in the initially cytological ATC group, four in the underestimated group and five in the false negative group. The most common US features of ATC were a solid (64.7%) and irregular shaped (88.2%) mass with lymph node involvement (76.4%). However, except for lymph node involvement (p=0.003), US findings for each group were not statistically different. The initial cytological diagnostic accuracy of ATC was 50% (9/18). Surgery was performed less in the ATC group (11%) and the false negative group (20%) than the underestimated group (75%).

Conclusion

The US features of ATC were not especially different from other types of aggressive thyroid cancer. A correct diagnosis of ATC by initial US-FNAB was made in 50% of the patients, which is significant in that therapeutic surgery can be undertaken in lower numbers if correctly diagnosed.  相似文献   
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CardioVascular and Interventional Radiology - Purpose Bronchopleural fistula is a rare but serious complication of lung ablation, as it is difficult to treat and is associated with a high mortality...  相似文献   
96.
Longitudinal standards for height and height velocity are essential to monitor for appropriate linear growth. We aimed to construct standards in Korean children and adolescents through the population-based longitudinal Kangwha study. Our study was a part of a community-based prospective cohort study from 1986 to 1999 with 800 school children. Height and height velocity were recorded annually from age 6 until final height. Results were compared with cross-sectional data from the 2007 Korean National Growth Charts. Final height was 173.5 cm in boys and 160.5 cm in girls. Although final height was similar between longitudinal and cross-sectional standards, the mean height for age was higher in the longitudinal standard by 1-4 cm from age 6 until the completion of puberty. Using the longitudinal standard, age at peak height velocity (PHV) was 12 in boys and 10 in girls; height velocity at PHV was 8.62 cm/yr in boys and 7.07 cm/yr in girls. The mean height velocity was less than 1 cm/yr at age 17 in boys and 15 in girls. Thus, we have presented the first report of longitudinal standards for height and height velocity in Korean children and adolescents by analyzing longitudinal data from the Kangwha cohort.  相似文献   
97.
To adopt the model for end-stage liver disease (MELD) score-based system in Korea, the feasibility should be evaluated by analysis of Korean database. The aim of this study was to investigate the feasibility of the MELD score-based system compared with the current Child-Turcotte-Pugh (CTP) based-system and to suggest adequate cut-off to stratify waiting list mortality among Korean population. We included 788 adult patients listed in waiting list in Seoul National University Hospital from January 2008 to May 2011. The short-term survival until 6 months after registration was evaluated. Two hundred forty six (31.2%) patients underwent live donor liver transplantation and 353 (44.8%) patients were still waiting and 121 (15.4%) patients were dropped out due to death. Significant difference was observed when MELD score 24 and 31 were used as cut-off. Three-months survival of Status 2A was 70.2%. However, in Status 2A patients whose MELD score less than 24 (n=82), 86.6% of patients survived until 6 month. Furthermore, patients with high MELD score (≥31) among Status 2B group showed poorer survival rate (45.8%, 3-month) than Status 2A group. In conclusion, MELD score-based system can predict short term mortality better and select more number of high risk patients in Korean population.  相似文献   
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99.
Medulloblastoma (MB) is a clinically and biologically heterogeneous group of tumors, and currently classified into four molecular subgroups (Wnt, Shh, Group 3 and Group 4). Intracellular signaling of the Wnt pathway has been divided into two classes: the “canonical” and the “non‐canonical” signaling pathway. The canonical signaling pathway is a well‐established, β‐catenin‐dependent signaling pathway in MB. In contrast, very little research about the non‐canonical WNT signaling pathway in MB exists. In order to identify the roles of Wnt‐5a and Ror2, two non‐canonical WNT pathway‐related genes, we studied 76 cases of MB with immunohistochemistry and quantitative real‐time PCR and correlated the results with clinicopathological and other molecular parameters and prognosis. Wnt5a and Ror2 were immunopositive in 20 (29.4%) and 35 (51.5%) of 68 cases, respectively. There were positive associations among protein expressions of Wnt5a, Ror2 and β‐catenin. Ror2 mRNA levels were well correlated with immunoexpression. Ror2 mRNA expression was significantly associated with CTNNB1 mutation. High Ror2 mRNA expression was an independent favorable prognostic factor. In conclusion, our study demonstrates the first attempt to identify Wnt5a and Ror2 as additional mechanisms contributing to dysregulation of the non‐canonical WNT signaling pathway in MB. Ror2 may play a role as an oncosuppressor in MB.  相似文献   
100.
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