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1.
Congenital rubella syndrome (CRS) results from maternal rubella virus infection in early pregnancy. Abnormal neuroimaging findings have been analyzed in a small number of CRS patients in the past; however, their clinical significance has been poorly addressed. Therefore, we have investigated the neuroimaging findings of 31 patients with CRS from previous studies. The most common finding was parenchymal calcification, which was observed in 18 of 31 patients (58.1%). A multivariable logistic regression model showed that it was associated with psychomotor or mental retardation (p = 0.018), suggesting that parenchymal calcification in CRS could be a prognostic factor.  相似文献   
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Genetic and epigenetic alterations importantly contribute to the pathogenesis of lung cancer. In the study, we measured the frequency and distribution of molecular abnormalities of EGFR as well as the aberrant promoter methylations of BRCA1, MGMT, MLH1, and RASSF1A in Vietnamese lung adenocarcinomas. We investigated the association between genetic and epigenetic alteration, and between each abnormality with clinicopathologic parameters. Somatic EGFR mutation that was found in 49/139 (35.3%) lung adenocarcinomas showed a significant association with young age, female gender, and non-smokers. EGFR overexpression was identified in 82 tumors (59.0%) and statistical relationships with EGFR or BRCA1 methylation but not EGFR mutation. In addition, EGFR, BRCA1, MGMT, MLH1, and RASSF1A methylations were found in 33 (23.7%), 41 (29.5%), 46 (33.1%), 28 (20.1%), and 41 (29.5%) cases of a total of 139 lung adenocarcinomas, respectively. The RASSF1A methylation was found to be linked to the smoking habit. Methylations in MGMT and RASSF1A were also found to correlate with metastasis status. Furthermore, the distribution of EGFR mutation and that of BRCA1, MGMT or RASSF1A methylation were significantly exclusive in lung adenocarcinomas. The main finding of our study demonstrate that epigenetic abnormalities might play a critical role for the lung tumorigenesis in patients with smoking history and metastasis, and partly affect the predictive value of EGFR mutations through blocking expression due to promoter EGFR hypermethylation. Mutually exclusive distribution of genetic and epigenetic alterations reflects differently biological characteristics in the etiology of lung adenocarcinomas.  相似文献   
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Background: Identification of germline and somatic BRCA1/2 mutations in ovarian cancer is important for genetic counseling and treatment decision making with poly ADP ribose polymerase inhibitors. Unfortunately, data on the frequency of BRCA1/2 mutations in Vietnamese patients are scare. Methods: We aim to explore the occurrence of BRCA1/2 mutations in 101 Vietnamese patients with ovarian cancer including serous (n = 58), endometrioid (n = 14), mucinous (n = 24), and clear cell (n = 5) carcinomas. BRCA1/2 mutations were detected from formalin-fixed parafin-embedded tumor samples using the OncomineTM BRCA Research Assay on Personal Genome Machine Platform with Ion Reporter Software for sequencing data analysis. The presence of pathogenic mutations was confirmed by Sanger sequencing. Results: We found no BRCA2 mutation in the entire cohort. Four types of pathogenic mutations in BRCA1 (Ser454Ter, Gln541Ter, Arg1751Ter, and Gln1779AsnfsTer14) were detected in 8 unrelated patients (7.9%) belonging to serous and endometrioid carcinoma groups. Except for the c.1360_1361delAG (Ser454Ter) mutation in BRCA1 exon 11 that was somatic, the other mutations in exons 11, 20, and 22 were germline.  Interestingly, the recurrent Arg1751Ter mutation in BRCA1 exon 20 appeared in 4 patients, suggesting that this is a founder mutation in Vietnamese patients. Conclusion: Mutational analysis of tumor tissue using next generation sequencing allowed the detection of both germline and somatic BRCA1/2 mutations.  相似文献   
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Background

Cranioplasty is a surgical procedure used to treat a bone defect or deformity in the skull. To date, there is little consensus on the standard-of-care for graft materials used in such a procedure. Graft materials must have sufficient mechanical strength to protect the underlying brain as well as the ability to integrate and support new bone growth. Also, the ideal graft material should be individually customized to the contours of the defect to ensure a suitable aesthetic outcome for the patient.

Purpose

Customized 3D-printed scaffolds comprising of polycaprolactone-β-tricalcium phosphate (PCL-TCP) have been developed with mechanical properties suitable for cranioplasty. Osteostimulation of PCL-TCP was enhanced through the addition of a bone matrix-mimicking heparan sulphate glycosaminoglycan (HS3) with increased affinity for bone morphogenetic protein-2 (BMP-2). Efficacy of this PCL-TCP/HS3 combination device was assessed in a rat critical-sized calvarial defect model.

Method

Critical-sized defects (5 mm) were created in both parietal bones of 19 Sprague Dawley rats (Male, 450–550 g). Each cranial defect was randomly assigned to 1 of 4 treatment groups: (1) A control group consisting of PCL-TCP/Fibrin alone (n = 5); (2) PCL-TCP/Fibrin-HSft (30 μg) (n = 6) (HSft is the flow-through during HS3 isolation that has reduced affinity for BMP-2); (3) PCL-TCP/Fibrin-HS3 (5 μg) (n = 6); (4) PCL-TCP/Fibrin-HS3 (30 μg) (n = 6). Scaffold integration and bone formation was evaluated 12-weeks post implantation by μCT and histology.

Results

Treatment with PCL-TCP/Fibrin alone (control) resulted in 23.7% ± 1.55% (BV/TV) of the calvarial defect being filled with new bone, a result similar to treatment with PCL-TCP/Fibrin scaffolds containing either HSft or HS3 (5 μg). At increased amounts of HS3 (30 μg), enhanced bone formation was evident (BV/TV = 38.6% ± 9.38%), a result 1.6-fold higher than control. Further assessment by 2D μCT and histology confirmed the presence of enhanced bone formation and scaffold integration with surrounding host bone only when scaffolds contained sufficient bone matrix-mimicking HS3.

Conclusion

Enhancing the biomimicry of devices using a heparan sulphate with increased affinity to BMP-2 can serve to improve the performance of PCL-TCP scaffolds and provides a suitable treatment for cranioplasty.  相似文献   
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