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151.
BACKGROUND: The high proportions of lymphoid tissues are thought to be one of the underlying factors inducing severe allograft rejection following small bowel transplantation. Mesenteric lymph nodes (MLN) contained in the intestinal graft are not only a source of donor-derived professional antigen-presenting cells, but also offer a field for immune interaction between donor and host cells. We investigated immune responses in graft MLNs with or without FK506 to develop a novel strategy to control small bowel allograft rejection. MATERIALS AND METHODS: Heterotopic small bowel transplantations were performed from Brown Norway donors to Lewis recipients. Changes in population of lymphocytes, expressions of costimulatory molecules, apoptosis, and cytokine profiles in graft MLNs were evaluated. RESULTS: The increase in apoptotic cells and cytokine responses relating to rejection in the graft MLNs developed prior to those in graft jejunum. While donor lymphocytes in graft MLNs were rapidly replaced to host-derived lymphocytes independent of FK treatment, increase in CD8(+) T cells in host population was seen only in recipients without FK506 treatment. The expressions of B7 molecules on donor cells in graft MLNs were significantly lower in the recipients with FK treatment. CONCLUSIONS: Immune responses in graft MLNs have significant impact on the outcome of the small bowel allograft. Apoptosis of graft MLN cells was well correlated with and ahead of progression of acute rejection. Modulation of costimulatory molecules on donor-derived MLN cells in the allograft and specific suppression of host CD8(+) T cells are possible ways to control severe rejection after allogeneic small bowel transplantation.  相似文献   
152.
BACKGROUND: Concerning the relationship between morphology and clinical outcome, there have been many reports using computed tomography/myelography but not so many using axial magnetic resonance imaging (MRI) of the spinal cord. This is the first report to correlate axial cord image, intensity changes in MRI, and cord expansion pattern using intraoperative ultrasonography. OBJECTIVE: The objectives were to correlate MRI studies, axial cord images/expansion, and changes in MRI intensity to see if there is a direct prognostic significance to these changes and to determine whether preoperative axial MRI images of the spinal cord predict recovery from compressive myelopathy. METHODS: Posterior cervical decompressions with laminoplasty were performed in 44 patients with cervical myelopathy due to ossification of the posterior longitudinal ligament. On T2-weighted MR images, the cross-sectional shape of the cord at the level of maximal compression was categorized as boomerang, teardrop, or triangle. Additionally, with use of intraoperative ultrasonography, the expansion pattern of the cord that occurred intraoperatively was contrasted with that seen on postoperative MR images. RESULTS: Clinical recovery rates were the worst for those with triangular, intermediate for those with boomerang, and the best for those with teardrop shape. Preoperative low T1 and high T2 signals were found in most cases with triangular cord configurations. Triangular cord configurations showed the least expansion among the three categorized spinal cords. CONCLUSION: Patients with triangular deformity of the cord have atrophy as confirmed on MR studies where there is a low T1 and high T2 signal in the cord. Poor postoperative clinical recovery correlates with the lack of postoperative cord expansion on either MR or ultrasound evaluations. Those with either teardrop or boomerang deformities demonstrate a relatively good recovery rate.  相似文献   
153.
STUDY DESIGN: A prospective study was conducted on the surgical procedures for lumbar disc herniation. OBJECTIVE: The objective of this study is to investigate the surgical outcomes of different methods when performed by the same surgeon, using a prospective study. BACKGROUND: Macro discectomy is widely known as a common surgical procedure for lumbar disc herniation, while microdiscectomy in place of Caspar technique (the Caspar method) and microendoscopic discectomy by a posterior approach are reported as less invasive surgical methods for this condition. However, there have not been a significant number of prospective studies conducted to compare different surgical procedures for lumbar disc herniation. MATERIALS AND METHODS: The target of our study was a group of 62 patients (male: 43, female: 19) who underwent surgery by macro discectomy (A group) and 57 patients (male: 33, female: 24) who underwent surgery by microdiscectomy in place of Caspar technique (B group). The mean ages at surgery were 34 (14 to 62) years and 41 (18 to 65) years respectively, and the mean duration of follow-up was 2 years and 8 months (12 months to 4 years). For all patients, the surgery was performed by 1 of the authors. The items investigated were the operation time, amount of bleeding, duration of hospitalization, amount of analgesic agent used after surgery, pre- and postoperative scores based on judgment criteria for treatment of lumbar spine disorders established by the Japanese Orthopaedic Association score, visual analog scales (VAS, 0 to 10) for lumbago before surgery and at discharge, VAS for sciatica before surgery and at discharge, perioperative complications, and cases requiring further surgery. RESULTS: There were no significant differences between the 2 surgical procedures in the frequency of use of an analgesic agent after surgery, the pre- and postoperative Japanese Orthopaedic Association scores or postoperative VAS for sciatica. Statistically significant differences were observed in the operation time, amount of bleeding, duration of hospitalization, and postoperative VAS for lumbar pain, but the differences were not large, and may not have been clinically significant. CONCLUSIONS: For herniotomy for lumbar disc herniation, both macro discectomy and microdiscectomy are appropriate, as long as surgeons have mastery of the procedures.  相似文献   
154.
BACKGROUND: The prognosis for the hepatocellular carcinoma (HCC) patient is affected by invasion and metastases. The attenuated expression of adherens junction protein epithelial-cadherin (E-cad) correlates with a more malignant potential in HCC. However, the potential of the claudin (CL) family of tight junctional proteins for HCC prognosis has remained unrecognized. MATERIALS AND METHODS: We immunohistochemically examined the expression of CL-1 and E-cad in resected specimens from 55 HCC cases. The percentage of CL-1- or E-cad-positive cells was counted in HCC cells and the surrounding hepatocytes and scored as 0 (0%), 1 (1-33%), 2 (34-66%), and 3 (67-100%). The expression of CL-1 or E-cad was considered "preserved" if the score in HCC was equal to or more than that in the surrounding hepatocytes, and "attenuated" if not so. RESULTS: In nontumorous tissue, CL-1 and E-cad were observed at the lateral surface of hepatocytes and biliary epithelial cells. In well-differentiated HCCs, the expression of CL-1 and E-cad was preserved in 12 of 14 cases. In poorly differentiated HCCs, E-cad expression was preserved in 9 of 18 cases, while CL-1 expression was preserved in only 4 cases (P<0.01 versus well-differentiated HCCs). HCCs with portal invasion showed significantly attenuated CL-1 expression than those without portal invasion (P<0.05). The survival rate after hepatectomy for HCC with attenuated CL-1 expression was significantly lower than that for HCC with preserved CL-1 expression. CONCLUSIONS: Attenuated expression of CL-1 closely correlates with the dedifferentiation and portal invasion of HCC. Down-regulated CL-1 expression may serve as a potential marker for a poor prognosis in HCC.  相似文献   
155.
We present a 70-year-old man who was referred for surgery with uncontrollable hypoglycemia. Ultrasonography and abdominal contrast computed tomography revealed a hypervascular tumor of 1 cm in diameter in the pancreatic tail. With a diagnosis of insulinoma, we performed a distal pancreatectomy. The patient showed a good postoperative course without any complications. The patient’s early morning fasting hypoglycemia disappeared. The respective levels of C-peptide and insulin dropped from 14.9 ng/mL and 4860 μIU/mL preoperatively to 5.3 ng/mL and 553 μIU/mL after surgery. A histopathological examination demonstrated that the tumor was a pancreatic neuroendocrine tumor, grade 1. Immunostaining was negative for insulin and positive for CD56, chromogranin A, synaptophysin and glucagon. These findings suggested that the tumor was clinically an insulinoma but histopathologically a glucagonoma. Among all insulinoma cases reported between 1985 and 2010, only 5 cases were associated with independent glucagonoma. In this report, we characterize and discuss this rare type of insulinoma by describing the case we experienced in detail.  相似文献   
156.
157.
The distribution of α1–6 chains of type IV collagen (α1–6(IV)) in human fetal kidneys was examined by indirect immunofluorescence. By 11 weeks of gestation, α1, 2, 3, 4, and 6(IV) were already present, but α5(IV) appeared relatively late, at 21 weeks. α1(IV) and α2(IV) were present in all basement membranes, α3(IV) and α4(IV) were restricted to the glomerular basement membrane and parts of the tubular basement membrane. α5(IV) was distributed in the glomerular basement membrane, Bowman’s capsule, and parts of the tubular basement membrane. α6(IV) was present in the Bowman’s capsule, parts of the tubular basement membrane, and occurred in parts of the glomerular basement membrane at the early capillary loop stage, but disappeared during the later capillary loop stage. Received October 23, 1997; received in revised form and accepted February 6, 1998  相似文献   
158.
Intracerebroventricular microinfusion of recombinant human tumor necrosis factor (rhTNF) and recombinant human interleukin-1β (rhIL-1β) suppressed food intake in rats. Central infusion of heat-inactivated rhTNF and rhIL-1β, bovine serum albumin, heparin or transforming growth factor-β had no such effect. Central infusion of rhIL-1β did not affect the dipsogenic response to central administration of angiotensin II. Peripheral administration of rhTNF and rhIL-1β in doses equivalent to or higher than those administered centrally had no effect. Electrophoretically applied rhTNF and rhIL-1β specifically suppressed the activity of glucose-sensitive neurons in the lateral hypothalamic area. Glucose-insensitive neurons were little affected. The results suggest that TNF and IL-1β act directly in the central nervous system to suppress feeding, and this effect may be operative during acute and chronic disease.  相似文献   
159.
Summary Two cases with prolapse of all four cardiac valves are described and compared with two similar ones previously reported. The severity and progression of regurgitation of each of the valves differed by case, despite having similar echocardiographic findings consistent with the diagnosis of multiple floppy valves. Two of the four patients had their aortic valve replaced because of severe regurgitation: the excised valves revealed myxomatous degeneration. None of the patients had any stigmata of Marfan or Ehlers-Danlos syndrome, except for the presence of hyperextensive joints. There may be an unknown collagen disorder that caused floppiness in all the valves.  相似文献   
160.
A patient with Richter's syndrome developed rapid generalized lymph node enlargement with a decrease of peripheral blood lymphocytes after recombinant human granulocyte colony-stimulating factor (rhG-CSF) therapy for neutropenia induced by chemotherapy. The lymphadenopathy subsided spontaneously following discontinuation of rhG-CSF medication. Reinstitution of rhG-CSF therapy was followed by the same response as during initial therapy. Histopathologically, the lesions were characteristic of diffuse large cell lymphoma (DLL) with no evidence of myeloid cell involvement. No spontaneous contraction of enlarged lymph nodes followed withdrawal of the second course, but the enlargement subsided with chemotherapy. The patient died of myocardial infarction. All residual tumors examined post mortem presented microscopic features of small lymphocytic lymphoma (SLL), and G-CSF receptor was demonstrated on these neoplastic cells by Northern blot hybridization analysis. This observation indicates that some B cell malignancies may retain G-CSF receptor and respond to G-CSF.  相似文献   
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