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981.
Tissue engineering scaffolds capable of sustained plasmid release can promote gene transfer locally and stimulate new tissue formation. We have investigated the scaffold design parameters that influence the extent and duration of transgene expression and have characterized the distribution of transfected cells. Porous scaffolds with encapsulated plasmid were fabricated from poly(lactide-co-glycolide) with a gas foaming procedure, with wet granulation employed to mix the components homogeneously prior to foaming. Wet granulation enhanced plasmid incorporation relative to standard procedures and also enhanced in vivo transgene expression, possibly through the increased loading and maintenance of the scaffold pore structure. The plasmid loading regulated the quantity and duration of transgene expression, with expression for 105 days achieved at the highest dosage. Expression was localized to the implantation site, though the distribution of transfected cells varied with time. Transfected cells were initially observed at the scaffold periphery (day 3), then within the pores and adjacent to the polymer (day 17), and finally throughout the scaffold interior (day 126). Delivery of a plasmid encoding VEGF increased the blood vessel density relative to control. Correlating scaffold design with gene transfer efficiency and tissue formation will facilitate application of plasmid-releasing scaffolds to multiple tissues.  相似文献   
982.
983.

Background  

We evaluated the long-term effect of stereotactic body radiation therapy (SBRT) for primary small hepatocellular carcinoma (HCC) ineligible for local therapy or surgery.  相似文献   
984.
Development and applications of a BRAF oligonucleotide microarray   总被引:1,自引:0,他引:1       下载免费PDF全文
We herein describe the development of a sensitive microarray hybridization method called competitive DNA hybridization (CDH) and its use for analysis of BRAF somatic mutations. These mutations have been identified in many human cancers, and fast, reliable BRAF mutation detection may one day facilitate directed therapy of BRAF-mutated tumors. Our fast, reliable mutation detection by CDH is based on the principle that competition among multiple fluorescent-labeled samples for binding to shared wild-type sequences should reduce nonspecific results and increase the positive signals of unshared mutated sequences. The positive signals can then be discriminated based on the labeling of each sample (ie, with Cy3, Cy5, or Alexa-594). For testing of this method, we developed a BRAF oligonucleotide microarray containing 65 mutation types (more than 95% of the known BRAF mutations) and validated this microarray with 20 colorectal cancer tissues/cancer cell lines with BRAF mutations and 60 BRAF-negative samples. In sum, we were able to screen up to nine cancer samples on a single BRAF microarray (three per CDH on three regions per slide), indicating that this method may dramatically decrease the experimental time, cost, and effort of mutation detection in BRAF and other genes amenable to microarray analysis.  相似文献   
985.
Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.  相似文献   
986.
The distinction between benign and malignant thyroid tumors is critical for the management of patients with thyroid nodules. We applied immunohistochemical staining for galectin-3, HBME-1, cytokeratin 19 (CK19), high molecular weight cytokeratin (HMWCK), cyclin D1 and p27(kip1) in 295 thyroid lesions to determine their diagnostic accuracy. The expression of all markers was significantly associated with differentiated thyroid carcinoma (DTC).The sensitivity for the diagnosis of DTC was 94.7% with galectin-3, 91.3% with HBME-1, and 90.3% with CK19. The specificities of these markers were 95.5%, 69.7%, and 83.1%, respectively. Combining these markers, co-expression of galectin-3 and CK19 or galectin-3 and HBME-1 was seen in 93.2% of carcinomas but in none of the benign nodules. Comparing follicular variant of papillary carcinoma (FVPC) with follicular carcinoma (FC), the expression of galectin-3, CK19, and HMWCK was significantly higher in FVPC. When comparing FC with FA, the expression of galectin-3 and HBME-1 was significantly higher in FC. These results suggest that 1) galectin-3 is a useful marker in the distinction between benign and malignant thyroid tumors, 2) the combined use of HBME-1 and CK19 can increase the diagnostic accuracy, and 3) the use of CK19 and HMWCK can aid in the differential diagnosis between PC and FC.  相似文献   
987.
Complications after transcatheter closure of patent ductus arteriosus   总被引:1,自引:0,他引:1  
To evaluate the short- and mid-term results and complications ensuing the transcatheter closure of patent ductus arteriosus (PDA). Between October 1999 and December 2005, 117 patients (34 males and 83 females) underwent attempted percutaneous closure of PDA with a minimum diameter of more than 3 mm. Follow-up evaluations were conducted at 1 day and 1, 3, 6, 12 months after the performance of the transcatheter closure. The median age of patients at catheterization was 11 yr (range, 0.6 to 68 yr), median weight was 30 kg (range, 6 to 74 kg), and the median diameter of PDA was 4 mm (range, 3 to 8 mm). This procedure was conducted successfully in 114 patients (97.4%), using different devices. Major complications were detected in 4 patients (3.4%); significant hemolysis (2), infective endocarditis (1), failed procedure due to embolization (1). Minor complications occurred in 6 patients (5.1%); mild narrowing of the descending aorta (2) and mild encroachment on the origin of the left pulmonary artery (4). Although the transcatheter closure of PDA may be considered to be effective, several complications, including hemolysis, embolization, infective endocarditis, and the narrowing of adjacent vessels may occur in certain cases.  相似文献   
988.
Benign schwannomas arise in neural crest-derived Schwann cells. They can occur almost anywhere in the body, but their most common locations are the central nervous system, extremities, neck, mediastinum, and retroperitoneum. Schwannomas occurring in the biliary tract are extremely rare and mostly present with obstructive jaundice. We recently experienced a case of extrahepatic biliary schwannomas in a 64-yr-old female patient who presented with intra- and extrahepatic bile duct and gallbladder stones during a screening program. To the best of our knowledge, extrahepatic biliary schwannomas associated with bile duct stones have not been reported previously in the literature.  相似文献   
989.
We report a case of 61-yr-old man with stable psoriasis who progressively developed generalized pustular eruption, erythroderma, fever, and hepatic dysfunction following oral terbinafine. Skin biopsy was compatible with pustular psoriasis. After discontinuation of terbinafine and initiating topical corticosteroid and calcipotriol combination with narrow band ultraviolet B therapy, patient's condition slowly improved until complete remission was reached 2 weeks later. The diagnosis of generalized pustular psoriasis (GPP) induced by oral terbinafine was made. To our knowledge, this is the first report of GPP accompanied by hepatic dysfunction associated with oral terbinafine therapy.  相似文献   
990.
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