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991.
Background The congenital anomaly pancreaticobiliary maljunction (PBM) is considered to be a precancerous disease. PBM carcinogenesis is believed to be an accumulation of gene abnormalities, but the early events causing PBM carcinogenesis are still unclear. In the present study, telomerase activity and Bcl-2 expression in the gallbladder mucosa of PBM and non-PBM gallbladders were investigated.Methods The operative gallbladder materials were from five control cases, two cases of non-PBM gallbladder cancer, three of PBM gallbladder cancer, and three of non-neoplastic PBMs. Multiple sampling was performed from each gallbladder. The studies performed were: (1) immunohistochemistry of p53, Ki-67, and Bcl-2; (2) survey of k-ras point mutations; and (3) measurement of telomerase activity in each sample.Results In the cases of non-PBM cancer, abnormalities from the above studies were detected only in the cancerous lesions. Normal-appearing mucosa did not show Bcl-2 expression or telomerase activity. However, in the cases of PBM cancer, normal-appearing mucosa showed telomerase activity and Bcl-2 expression, but did not show p53, Ki-67, or k-ras abnormalities. In the non-neoplastic PBM, all samples showed Bcl-2 expression, and many showed telomerase activity.Conclusions Bcl-2 expression and activation of telomerase are probably early events causing carcinogenesis of the PBM gallbladder mucosa. They might be important factors causing carcinogenesis associated with chronic inflammation.  相似文献   
992.
Background Mesangial matrix expansion is caused by the overproduction and/or the impaired proteolytic degradation of the extracellular matrix. However, the relative contribution of these changes to the development of prolonged mesangial matrix expansion is still poorly understood. We aimed to elucidate the relative role of the matrix metalloproteinase (MMP)/tissue inhibitors of metalloproteinases (TIMPs) system in the development of prolonged mesangial matrix expansion.Methods We prepared two rat models, showing reversible or prolonged mesangial matrix expansion, induced by a single injection or two consecutive injections of anti-Thy-1.1 monoclonal antibody 1-22-3, respectively. We analyzed the glomerular expression of type I and type IV collagens; MMP-2, -9, and -13; membrane type 1-MMP (MT1-MMP); TIMP-1; and urinary type I collagen-degrading activity in both models.Results There were no differences in glomerular mRNA levels of type I and type IV collagens between the reversible and the prolonged models. MMP-9 mRNA expression and protein level was lower in the prolonged model than in the reversible one, whereas there were no differences in mRNA levels of MMP-2, -13, MT1-MMP, or TIMP-1 between the two models. Urinary type I collagen-degrading activity in the prolonged model was lower than that in the reversible one. Furthermore, there was a significant correlation between the mesangial matrix expansion and urinary type I collagen-degrading activity.Conclusions Impaired expression of MMP-9 may contribute to the development of prolonged mesangial matrix expansion. Analysis of urinary type I collagen-degrading activity may provide additional diagnostic information in mesangial proliferative glomerulonephritis.  相似文献   
993.
OBJECTIVE: Ultrasound (US) has been used as a tool to determine the indication for surgery for neonatal ovarian cysts. The purpose of this study was to investigate whether magnetic resonance imaging (MRI) contributes to optimal management. METHODS: Between 1993 and 2001, US and MRI studies were simultaneously performed on 13 consecutive infants younger than 2 months of age with ovarian cysts. The US Patterns were classified as complex or simple. Signal intensity (SI) of the cysts on MRI was compared with that of the liver on T1-weighted images (T1WI) and with urine on T2-weighted images (T2WI). We assumed that high SI on T1WI and iso or low SI on T2WI indicated complications. RESULTS: There were 10 complex and three simple cysts on US. Of the 10 complex cysts, two had no complications at surgery or resolved spontaneously. These two cysts showed low SI on T1WI. Eight complex cysts showed high SI on T1WI and all were haemorrhagic. The US diagnosis corresponded to the MRI findings in three simple cysts. The sensitivity of US for haemorrhage was 80%, and that of MRI was 100%. CONCLUSIONS: We found that MRI was a more reliable diagnostic modality than US for diagnosing neonatal ovarian cysts.  相似文献   
994.
Owing to the severe shortage of cadaveric grafts in Japan, we have performed ABO-incompatible living donor kidney transplantation since 1989. This study assessed short- and long-term outcomes in 441 patients who received ABO-incompatible living donor kidney transplants between January 1989 and December 2001. We compared our results with historical data from 1055 recipients of living kidney transplantation. Overall patient survival rates 1, 3, 5, 7, and 9 years after ABO-incompatible transplantation were 93%, 89%, 87%, 85%, and 84%, respectively. Corresponding overall graft survival rates were 84%, 80%, 71%, 65%, and 59%. After ABO-incompatible transplantation, graft survival rates were significantly higher in patients 29 years or younger than in those 30 years or older and in patients who received anticoagulation therapy than in those who did not receive such therapy. There were no significant differences between A-incompatible and B-incompatible recipients with respect to clinical outcomes. The graft survival rate at 1 year in the historical controls was slightly but not significantly higher than that in our recipients of ABO-incompatible transplants. We conclude that long-term outcome in recipients of ABO-incompatible living kidneys is excellent. Transplantation of ABO-incompatible kidneys from living donors is a radical, but effective treatment for end-stage renal disease.  相似文献   
995.
A 41-year-old man presented with progressive worsening of postural headache. Computed tomography (CT) showed bilateral subdural hematomas without prior history of trauma. The diagnosis was spontaneous intracranial hypotension (SIH). Conservative treatment with oral steroids failed to prevent gradual deterioration of the patient's consciousness. CT myelography revealed massive cerebrospinal fluid (CSF) leakage between the C-1 and C-2 levels. The leak was repaired surgically via a laminectomy. A cyst, thought to be a meningeal cyst, was discovered adjacent to the right C-2 nerve root, and CSF was seen seeping out from around the cyst after a Valsalva maneuver. The presumed dural defect of the cyst was sealed by packing with muscle fragments and fibrin glue. The symptoms disappeared soon after surgery. He was discharged 1 month after surgery without deficits. Most SIH cases are benign and can be managed conservatively, or by the epidural blood patch method. Surgery is more invasive than the epidural blood patch method, but should be performed in patients with a high cervical lesion and massive CSF leakage.  相似文献   
996.
Hand-assisted laparoscopic splenectomy for splenic tumors   总被引:3,自引:0,他引:3  
BACKGROUND: The feasibility of hand-assisted laparoscopic splenectomy (HALS) for splenic tumors including benign or malignant neoplasms and the associated clinical outcome of the patients remain unclear. METHODS: A total of 10 patients with splenic tumors undergoing HALS were retrospectively analyzed in this study. The intraoperative course, postoperative course, and postoperative recovery were evaluated. RESULTS: Ten patients with splenic tumors consisted of 5 with benign tumors and 5 with malignant tumors. HALS was not converted to an open splenectomy in any of the patients. Mean operative time was 170 min (range 100-310 min). Mean estimated blood loss was 105 g (range 10-900 g). Mean splenic size and splenic weight was 13 cm and 478 g, respectively. Splenomegaly based on size or weight occurred in 50% of the patients. There were no intra- or postoperative complications. Postoperative chemotherapy was given to 4 patients with malignant tumors including metastatic carcinomas and malignant lymphomas. All the patients were alive at a mean follow-up of 26 months, ranging from 15 to 43 months after surgery. There was no port-site recurrence after surgery in our study. Mean time to first flatus, mean time to first walking, mean time to resumption of oral intake, mean length of hospital stay, and mean duration of epidural analgesia were 1.8, 1, 1.5, 10.8 and 3.1 days, respectively. The results were equal in terms of intra- and postoperative course to those seen with a standard laparoscopic splenectomy for 13 patients with idiopathic thrombocytopenic purpura. CONCLUSION: HALS may be a good indication for malignant tumors as well as benign tumors of the spleen.  相似文献   
997.
PURPOSE: We describe our experience of sling removal performed after either the Vesica sling procedure (due to vaginal erosion or at the time of reoperation for recurrent stress incontinence) or the tension-free vaginal tape (TVT) procedure (due to persistent urinary retention). MATERIALS AND METHODS: From May 1997 to December 2002, we performed 19 Vesica sling procedures and 66 TVT procedures for the treatment of urodynamic stress incontinence. In the former procedures, four patients (21%) developed vaginal erosion and underwent total or partial removal of sling material (Hemashield made from bovine-collagen-injected woven polyester). In another three patients, stress incontinence recurred 2-4 years after the Vesica sling procedure, and they underwent total sling removal and the TVT procedure. Before using the urethral pull-down process (UPDP) in TVT procedures, 2 out of 23 patients (8.7%) developed persistent urinary retention and underwent either sling release alone or partial sling removal concomitant with a second TVT procedure. After the introduction of the UPDP, no patient developed urinary retention. RESULTS: Three patients in whom total sling removal was performed due to vaginal erosion after a Vesica sling procedure developed recurrent stress incontinence. One patient who underwent partial sling removal remained continent, but vaginal erosion recurred 2 years later. Patients who had total sling removal and TVT procedures due to recurrent stress incontinence after Vesica sling procedure became continent with an uneventful postoperative course. One patient who underwent transvaginal release of TVT tape (polypropylene mesh) due to urinary retention after the TVT procedure developed recurrent stress incontinence, and the other who underwent partial removal of TVT tape and a second TVT procedure had resolution of urinary retention without recurrence of stress incontinence. CONCLUSION: Prompt and total sling removal should be recommended for vaginal erosion after the Vesica sling procedure. In patients with urinary retention after the TVT procedure, partial removal of TVT tape and a second TVT procedure using the UPDP to prevent overtightness may be a preferable choice to attain both continence and resolution of urinary retention.  相似文献   
998.
BACKGROUND: Both propofol and thiamylal inhibit adenosine triphosphate-sensitive potassium (KATP) channels. In the current study, the authors investigated the effects of these anesthetics on the activity of recombinant sarcolemmal KATP channels encoded by inwardly rectifying potassium channel (Kir6.1 or Kir6.2) genes and sulfonylurea receptor (SUR1, SUR2A, or SUR2B) genes. METHODS: The authors used inside-out patch clamp configurations to investigate the effects of propofol and thiamylal on the activity of recombinant KATP channels using COS-7 cells transfected with various types of KATP channel subunits. RESULTS: Propofol inhibited the activities of the SUR1/Kir6.2 (EC50 = 77 microm), SUR2A/Kir6.2 (EC50 = 72 microm), and SUR2B/Kir6.2 (EC50 = 71 microm) channels but had no significant effects on the SUR2B/Kir6.1 channels. Propofol inhibited the truncated isoform of Kir6.2 (Kir6.2DeltaC36) channels (EC50 = 78 microm) that can form functional KATP channels in the absence of SUR molecules. Furthermore, the authors identified two distinct mutations R31E (arginine residue at position 31 to glutamic acid) and K185Q (lysine residue at position 185 to glutamine) of the Kir6.2DeltaC36 channel that significantly reduce the inhibition of propofol. In contrast, thiamylal inhibited the SUR1/Kir6.2 (EC50 = 541 microm), SUR2A/Kir6.2 (EC50 = 248 microm), SUR2B/Kir6.2 (EC50 = 183 microm), SUR2B/Kir6.1 (EC50 = 170 microm), and Kir6.2DeltaC36 channels (EC50 = 719 microm). None of the mutants significantly affects the sensitivity of thiamylal. CONCLUSIONS: These results suggest that the major effects of both propofol and thiamylal on KATP channel activity are mediated via the Kir6.2 subunit. Site-directed mutagenesis study suggests that propofol and thiamylal may influence Kir6.2 activity by different molecular mechanisms; in thiamylal, the SUR subunit seems to modulate anesthetic sensitivity.  相似文献   
999.
BACKGROUND: Gitelman's syndrome (GS) is an autosomal recessive disorder resulting from inactivating mutations in the thiazide-sensitive Na-Cl co-transporter (NCCT) gene. To date, almost 90 mutations have been identified. It is possible that there is a population-specific distribution of mutations. In this study, we analysed mutations in the NCCT gene of seven Japanese patients with GS. METHODS: Peripheral blood mononuclear cells were isolated from patients with GS, their family members and healthy control subjects. A mutation analysis of the NCCT gene was performed completely by direct automated sequencing of polymerase chain reaction-amplified DNA products. In patients with a deletion or splice site mutation, we undertook cDNA sequence analysis. RESULTS: We identified nine mutations. Five of them [c.185C>T (Thr60Met), c.1712C>T (Ala569Val), c.1930C>T (Arg642Cys), c.2552T>A (Leu849His) and c.1932delC] have been reported in Japanese patients, but not in GS patients from other ethnic groups. The remaining four mutations [c.7A>T (Met1Leu), c.1181_1186+20del26, c.1811_1812delAT and IVS16+1G>A] were novel. In cDNA derived from a patient with c.1181_1186+20del26, a deletion of exon 9 and a frameshift at the start of exon 10 were observed. In cDNA derived from patients with IVS16+1G>A, an additional 96 bp insertion between exons 16 and 17 was observed. Six out of seven patients were compound heterozygotes, and the remaining one carried a single heterozygous mutation. CONCLUSIONS: We found four novel mutations in the NCCT gene in seven Japanese patients with GS. Moreover, our study suggests that the distribution of mutations in the NCCT gene in Japanese GS patients potentially differs from that in other populations.  相似文献   
1000.
OBJECTIVES: The purpose of this study was to determine the most suitable candidates for scalene lymph node biopsy to detect non-palpable scalene lymph node metastasis (N(3)-scalene) in non-small cell lung cancer patients. METHODS: Standard cervical mediastioscopies and ipsilateral scalene lymph node biopsies were performed preoperatively by a single surgeon on 121 consecutive patients with non-small cell lung cancer scheduled to have surgical resection between January 1997 and August 2002, who had neither evidence of distant metastasis on imaging diagnosis nor palpable supraclavicular lymph nodes. RESULTS: N(3)-scalene was detected in six patients (5.0%), who all had non-squamous cell carcinoma, including one (1.0%) out of 98 patients with negative standard cervical mediastinoscopy and five (21.7%) out of the remaining 23 patients with positive mediastinal lymph node involvement. There was a significant difference in the incidence of the N(3)-scalene between the two groups (P<0.01). Five patients with N(3)-scalene had metastatic lesions in the multilevel mediastinal lymph node station on the same side as the cancer (multilevel N(2)), and accounted for 31.3% of 16 patients with multilevel N(2) disease. The N(3)-scalene was detected in 5 (45.5%) of 11 patients with lung cancer classified as non-squamous cell carcinoma with multilevel N(2) disease. CONCLUSIONS: The results of the present study suggest that non-palpable scalene lymph node biopsy is indicated for lung cancer patients diagnosed as having non-squamous cell carcinoma with mediastinoscopic multilevel N(2) disease.  相似文献   
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