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931.
Conventional aortic valve replacement (AVR) is the gold standard surgical treatment for symptomatic aortic valve stenosis. However, some patients are not referred for open surgical procedure because of their high risk due to complicated co-morbidities. We describe the first case in Japan of successful transcatheter aortic valve implantation (TAVI). An 81-year-old woman with severe interstitial pneumonia was referred for significant aortic valve stenosis. Conventional AVR might have been risky, so TAVI was planned after informed consent was obtained. Under general anesthesia was established, a 23-mm Edwards SAPIEN transcatheter heart valve was implanted through the common iliac artery. Postoperative echocardiographic assessment showed satisfactory hemodynamic function with a stable valve position, and she was discharged on day 7 without complications. At the 6-month follow-up, there had been no untoward events, and there was marked improvement in her functional status. TAVI for symptomatic aortic valve stenosis is a less invasive, alternative approach for high-risk patients.  相似文献   
932.
933.
934.
Neuroglial heterotopias (NGH) are rare congenital head and neck lesions composed of differentiated neuroectodermal tissue and representing developmental heterotopias rather than true neoplasms. The case of a male neonate with respiratory distress and early feeding problems depicting a retropharyngeal space mass which in the intraoperative squash smears revealed glial cells with multiple cytoplasmic processes is reported here. Small clusters of cuboidal epithelial cells with rosette-like ependymal structures and cuboidal cells arranged in sheets or branching folds suggestive of choroid plexus cells were also identified. Through this cytological approach a cytologic diagnosis of a NGH or low-grade astrocytoma was suggested. Further evaluation and immunohistochemical studies were conducted on formalin-fixed, paraffin-embedded material. Glial cells, ependymal structures and choroid plexus were identified on H&E sections. Immunohistochemically, the glial cells showed diffuse and strong cytoplasmic staining for glial fibrillary acidic protein (GFAP) and S-100 protein and focal immunoreactivity for synaptophysin and neurofilament. The proliferative index with MIB-1 was around 4%. The diagnosis of NGH of the retropharyngeal space was confirmed based on the clinical, cytopathologic, histopathology, immunohistochemical results, and the location of the tumor. We demonstrated here for the first time the cytopathological features of NGH of the retropharyngeal space with emphasis on differential diagnostic considerations.  相似文献   
935.
We retrospectively analyzed 12 consecutive adult severe aplastic anemia patients who received unrelated umbilical cord blood transplantation after a reduced-intensity conditioning regimen (RI-UCBT). The conditioning regimen consisted of 125 mg/m2 fludarabine, 80 mg/m2 melphalan, and 4 Gy of total body irradiation. The median infused total nucleated cell number and CD34(+) cell number were 2.50 × 10?/kg and 0.76 × 10?/kg, respectively. Eleven of the 12 patients achieved primary neutrophil and platelet engraftment. All patients who achieved engraftment had complete hematologic recovery with complete donor chimerism, except for one patient who developed late graft failure 3 years after RI-UCBT. Two of the 12 patients died of idiopathic pneumonia syndrome, and the remaining 10 patients are alive, having survived for a median of 36 months. Our encouraging results indicate that RI-UCBT may become a viable therapeutic option for adult severe aplastic anemia patients who lack suitable human leukocyte antigen-matched donors and fail immunosuppressive therapy.  相似文献   
936.
Gangliocytic paraganglioma (GP) is generally considered to be a benign periampullary lesion, although it is unclear whether it should be classified as a hamartoma or as a neoplasm. Here, we present a GP case with lymph node metastasis. A 16-year-old boy complained of exertional dyspnea. Upper endoscopy and imaging studies revealed a polypoid ampullary tumor. Pancreaticoduodenectomy with lymph node dissection was performed due to swelling of peripancreatic lymph nodes. Histologically, the tumor consisted of three cell types: epithelioid; spindle; and ganglion cells. In addition to these typical components of GP, a distinct glandular component was also present. There was substantial invasion of tumor cells into the lymphovascular vessels, associated with lymph node metastases. These lymph node metastases were histologically similar to the primary tumor. To judge from these findings GP may be a true neoplasm with metastatic capacity. Pre- and intraoperative investigations for lymph node or distant metastases are required for adequate resection of this kind of tumor.  相似文献   
937.
Undifferentiated pleomorphic sarcoma of bone (UPSb) is a rare tumor often difficult to differentiate from fibrosarcoma of bone (FSb), diagnostically. We applied array comparative genomic hybridization (array CGH) to screen for genes with potential importance in the tumor and compared the results with alterations seen in FSb. Twenty-two fresh frozen tissue specimens from 20 patients (18 primary tumors and 4 local recurrences) with UPSb were studied. DNA was isolated and hybridized onto Agilent 244K CGH oligoarrays. The hybridization data were analyzed using Agilent DNA Analytics Software. The number of changes ranged from 2 to 168 (average = 66). Losses were most frequently seen at 8p, 9p, 10, 13q, and 18q, and gains at 4q, 5p, 6p, 7p, 8q, 12p, 14q, 17q, 19p, 20q, 22q, and X. Homozygous deletions of CDKN2A, RB1, TP53, and ING1 were seen in 8/20, 7/20, 3/20, and 2/20 cases, respectively. Hypermethylation of both p16(INK4a) and p14(ARF) was found in two cases with loss at CDKN2A. Inactivation either of CDKN2A, RB1, or TP53 was detected in 18/20 cases. One case showed high level gains of CDK4 and MDM2. Frequent gains were seen at MYC, PDGFRA, KIT, and KDR. Immunohistochemical positivity of KIT, PDGFRA, KDR, and PDGFRB was found in 8/14, 5/14, 4/14, and 4/14 cases, respectively. The regions most significantly discriminating between UPSb and FSb included RB1 and MYC. No homozygous deletions of RB1 were found in FSb. In conclusion, our analysis showed the disruption of G1/S checkpoint regulation to be crucial for the oncogenesis of UPSb.  相似文献   
938.
The brain has emerged as a target for the insulin-sensitizing effects of several hormonal and nutrient-related signals. The current studies were undertaken to investigate mechanisms whereby leptin lowers circulating blood glucose levels independently of insulin. After extending previous evidence that leptin infusion directly into the lateral cerebral ventricle ameliorates hyperglycemia in rats with streptozotocin-induced uncontrolled diabetes mellitus, we showed that the underlying mechanism is independent of changes of food intake, urinary glucose excretion, or recovery of pancreatic β-cells. Instead, leptin action in the brain potently suppresses hepatic glucose production while increasing tissue glucose uptake despite persistent, severe insulin deficiency. This leptin action is distinct from its previously reported effect to increase insulin sensitivity in the liver and offers compelling evidence that the brain has the capacity to normalize diabetic hyperglycemia in the presence of sufficient amounts of central nervous system leptin.  相似文献   
939.
We report a case of pulmonary infection caused by a rare Nocardia species, Nocardia beijingensis, in a 48-year-old man who received multiple immunosuppressive therapy after renal transplantation. This pathogen was isolated from a bronchoscopic protected specimen brush and was identified as N. beijingensis by 16S rRNA gene sequence analysis. The patient was initially treated with imipenem/cilastatin followed by ceftriaxone and oral minocycline. Traditionally, trimethoprim-sulfamethoxazole (SXT) has been one of the first-line antibiotics chosen as an initial therapy for pulmonary nocardiosis, but this case was successfully treated without SXT. Considering recent reports about failures of both prophylaxis and treatment for nocardial infections with SXT and its various side effects, treatment with beta-lactam antibiotics and minocycline for pulmonary nocardiosis can be chosen in mild to moderate cases with confirmed susceptibility to these antibiotics in vitro.  相似文献   
940.
Recent studies have demonstrated that the Ten-eleven translocation (Tet) family proteins can enzymatically convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). While 5mC has been studied extensively, little is known about the distribution and function of 5hmC. Here we present a genome-wide profile of 5hmC in mouse embryonic stem (ES) cells. A combined analysis of global 5hmC distribution and gene expression profile in wild-type and Tet1-depleted ES cells suggests that 5hmC is enriched at both gene bodies of actively transcribed genes and extended promoter regions of Polycomb-repressed developmental regulators. Thus, our study reveals the first genome-wide 5hmC distribution in pluripotent stem cells, and supports its dual function in regulating gene expression.  相似文献   
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