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11.
Large cell neuroendocrine carcinoma (LCNEC) of the uterine cervix is a newly introduced category of the revised World Health Organization classification. We reported a case of cervical LCNEC with cytogenetic analysis by comparative genomic hybridization (CGH). The cervical tumor showed moderately increased mitotic activity (8-14 mitotic figures per 10 high-power fields) and focal necrosis, which made it problematic to differentiate from atypical carcinoid. CGH analysis failed to detect chromosome 11q loss that has been reported to be characteristic of pulmonary atypical carcinoids. Furthermore, chromosome 3q amplification, which has been detected frequently in pulmonary small cell carcinomas and LCNECs but not in pulmonary typical and atypical carcinoids, was the most remarkable chromosomal aberration. Although CGH reports are extremely rare in neuroendocrine tumors of the uterine cervix, specific chromosomal aberrations may be useful in their distinction.  相似文献   
12.
The dynamic characteristics of the baroreflex neural arc from pressure input to efferent sympathetic nerve activity (SNA) reveal derivative characteristics in the frequency range of 0.01 to 0.8 Hz (i.e., the baroreflex gain augments with increasing frequency) and high-cut characteristics in the frequency range above 0.8 Hz (i.e., the baroreflex gain decreases with increasing frequency) in rabbits. The derivative characteristics accelerate the arterial pressure regulation via the baroreflex. The high-cut characteristics preserve the baroreflex gain against pulsatile pressure by attenuating the high-frequency components less necessary for arterial pressure regulation. However, to what extent the carotid sinus baroreceptor transduction from pressure input to afferent baroreceptor nerve activity (BNA) contributes to these characteristics remains unanswered. To test the hypothesis that the carotid sinus pressure-BNA transduction partly explains the derivative characteristics but not the highcut characteristics, we examined the dynamic BNA response to pressure input in the frequency range from 0.01 to 3 Hz by using a white noise analysis in 7 anesthetized rabbits. The transfer function from pressure input to BNA showed slight derivative characteristics in the frequency range from 0.01 to 0.3 Hz with approximately a 1.7-fold increase in dynamic gain, but it showed no high-cut characteristics. In conclusion, the carotid sinus baroreceptor transduction partly explained the derivative characteristics but not the high-cut characteristics of the baroreflex neural arc. The present results suggest the importance of the central processing from BNA to efferent SNA to account for the overall dynamic characteristics of the baroreflex neural arc.  相似文献   
13.
Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
14.
Alterations of genomic DNAs in 9 papillary thyroid carcinomas and 3 follicular thyroid adenomas were examined by restriction landmark genomic scanning, a 2-dimensional gel analysis that allows detection of deletions, amplifications and other rearrangements of genomic DNA. DNAs from both thyroid tumors and associated non-tumorous glandular tissues were cleaved with the restriction enzyme NotI end-labeled with P-32 and size-fractionated by 2-dimensional electrophoresis using HinfI in a second digestion. The altered spots in carcinomas and adenomas were compared with those in nontumorous samples. Five and 4 spots were commonly amplified in carcinomas and adenomas, respectively. One amplified spot was apparently specific only for carcinoma and was not detected in any of adenomas examined. In contrast, 12 spots reduced in intensity were frequently observed in tumors, although a subset of 5 were more sporadically affected in adenomas. The results indicate both common and distinct genetic abnormalities occurring in thyroid tumors, which may relate to the different biological behaviors of malignant and benign neoplasms.  相似文献   
15.
To examine the potential role of pl6/CDKN2 gene mutations in prostate tumorigenesis, focal areas within individual tumors were investigated. Eleven cases of histologically heterogeneous prostate carcinomas obtained by radical prostatectomy were subjected to analysis of p16/CDKN2 gene mutations. DNA was extracted from 5 to 10 separate areas of each tumor with different growth or histological patterns. Exons 1 through 3 of the p16/CDKN2 gene were amplified using the polymerase chain reaction (PCR) and screened for homozygous deletions and mutations of this gene by single-strand conformation polymorphism (SSCP) analysis. No homozygous deletions were observed in any of the prostate carcinomas, but two of the eleven tumors demonstrated mutations in exon 2 of p16/CDKN2 gene. Missense mutations were detected in only one and two foci, respectively, out of six ana ten selected tumor areas. The present results suggest that p16/CDKN2 gene mutations, although they occur at a low incidence, are involved in prostate tumorigenesis, indicating a mutational heterogeneity in addition to morphological heterogeneity.  相似文献   
16.
Four cases of Stanford type A acute aortic dissection were treated by wrapping operation. After careful dissection between the dilated ascending aorta and right pulmonary artery, 8 mm woven Dacron vascular prosthesis was passed around the aorta and tightened. Further enforcement wrapping was carried out using several prostheses from aortic root to the innominate artery. We call this technique "wrapping operation". Emergent operations were performed on all patients because of cardiac tamponade, 6.8-33 hours after the onset of dissection. Three patients are doing well 17-39 months after the operation, but only 1 patient died early postoperative period because of DIC and multiple organ failure. And 2 patients was showed closure of entry of the ascending aorta by the postoperative aortography. We think that the wrapping operation is a useful technique for the patients of ruptured Stanford type A acute dissecting aneurysms.  相似文献   
17.
PURPOSE: Selection of appropriate protocols for treatment of superficial esophageal squamous cell carcinoma (SESCC) is dependent on lymph node metastasis status. Therefore, it is important to know whether lymph node metastasis is present before treatment. EXPERIMENTAL DESIGN: In this study, we examined the relation between DNA sequence copy number aberrations detected by comparative genomic hybridization and lymph node metastasis in 26 surgically resected SESCCs (training samples). We then assessed whether the genetic information is predictive for nodal status in biopsy specimens from eight newly enrolled patients with SESCC (blinded samples). RESULTS: Pathological examination revealed that 17 of 26 training samples (65.4%) did not have associated lymph node metastasis. Gains of 8q24 and/or 20q12-qter were observed in 12, including all (nine of nine) with nodal metastasis. Fourteen training samples did not have gain of either 8q24 or 20q12-qter. Of the blinded samples, two showed no gain of 8q24 or 20q12-qter, and as anticipated the postoperative pathological examination revealed no nodal metastasis. The remaining six blinded samples had gains of 8q24 and/or 20q12-qter, and lymph node metastasis was detected by postoperative examination in four of these tumors. CONCLUSIONS: Absence of gains of 8q24 and/or 20q12-qter appears to be associated with absence of lymph node metastasis in patients with SESCC; therefore, less invasive surgery can be chosen.  相似文献   
18.
Castleman's disease is a rare atypical lymphoproliferative disorder. Renal manifestations, such as proteinuria, hematuria, and renal dysfunction, are common in Castleman's disease; however, a nephrotic syndrome rarely occurs. We have encountered an unusual case of Castleman's disease of the plasma cell type characterized by nephrotic syndrome because of glomerulopathy mimicking membranoproliferative glomerulonephritis. Our patient showed higher levels of circulating cytokines (interleukin-6/vascular endothelial cell-derived growth factor), the glomerular lesions not associated with immunocomplex deposition, and the resolution of nephrotic syndrome after successful corticosteroids therapy resulting in a decline in cytokines levels, thereby implicating a cytokine-induced glomerular cell injury/activation as a possible cause of the glomerular pathological changes in this case.  相似文献   
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