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81.
BACKGROUND: We evaluated the importance and mechanism of graft and host accommodation in hamster-to-rat cardiac xenotransplantation models. METHODS: To evaluate graft accommodation, accommodated hamster grafts (Group 2) were transplanted to na?ve host rats treated with FK506, and compared with na?ve hamster grafts (Group 1). To evaluate host accommodation, three groups were evaluated: naive hamster hearts were transplanted to na?ve hosts treated with FK506 (Group 3: 0.5 mg/kg, Group 4: 1.0 mg/kg) and splenectomy, and compared with accommodating hosts (Group 5) with FK506 0.5 mg/kg and splenectomy. We examined graft survival, histopathology, antihamster antibodies and B-1 cells in blood. RESULTS: Graft survival in Group 2 (3.4+/-0.9 days) was not significantly different from that in Group 1 (2.8+/-0.4 days). Graft survival in Groups 4 and 5 (>30 days) was significantly prolonged compared with that in Group 3 (6.0+/-0.7 days). Histopathology of Groups 1-3 showed humoral rejection, whereas Groups 4 and 5 showed normal histology and expression of protective genes. In Groups 1-3, antihamster immunoglobulin (Ig) M and B-1 cells increased significantly compared to Groups 4 and 5, where IgM and B-1 cells remained low or were reduced. CONCLUSIONS: Host accommodation was more important than graft accommodation. Accommodating grafts expressing protective genes were rejected with an elevation of both IgM and B-1 cells. In accommodated hosts, both IgM and B-1 cells decreased, suggesting that B-1 cells may be responsible for the production of antihamster antibodies. These results suggest that sufficient suppression of B-1 cells, resulting in decreased titers of antihamster antibodies, may play an important role in host accommodation.  相似文献   
82.
A 65-year-old woman with a 48-year history of Behçet’s disease associated with nephrotic syndrome is described. Immunofluorescence study revealed IgA nephropathy. Following treatment with an angiotensin II type-I receptor-blocker, an anti-platelet drug, and an HMG-CoA reductase inhibitor, accompanied by dietary restrictions of protein and sodium, proteinuria was markedly decreased. This report describes our experience with a rare entity of Behçet’s disease complicated by nephrotic syndrome due to IgA nephropathy. Routine urine examination and renal biopsy are needed for the detection and diagnosis of renal problems with Behçet’s disease.  相似文献   
83.
Umehara Y  Hakamada K  Seino K  Aoki K  Toyoki Y  Sasaki M 《Surgery》2001,130(3):513-520
BACKGROUND: We evaluated the effects of intraperitoneal transplantation of microencapsulated hepatocytes in a 3-stage total hepatectomy rat model. METHODS: A new model of total hepatectomy was created as follows. First, the infrahepatic inferior vena cava was ligated just above the right renal vein. Seven days later, the portal vein was ligated and a portacaval shunt was established using a Teflon catheter over a venipuncture needle. Another 7 days later, total hepatectomy was completed by ligating and dividing the suprahepatic inferior vena cava, the hepatic artery, and the bile duct. Next, 4 x 10(7) hepatocytes (4% of the normal liver hepatocyte mass) isolated from male Wistar rats were microencapsulated within a collagen matrix enveloped by a 3-layer membrane of sodium alginate-poly-L-lysine-sodium alginate copolymer. Capsules containing hepatocytes (diameter, 500-800 microm) and empty capsules (control) were transplanted intraperitoneally 4 days before the total hepatectomy. Survival time and selected blood chemistry concentrations after the total hepatectomy were measured. The capsules were also examined histologically with hematoxylin and eosin staining and modified Gmelin's stain for bile pigments. RESULTS: The survival time was greater in the rats given the microencapsulated hepatocytes than in the control rats (17.3 +/- 3 vs 3.7 +/- 0.1 hours; P <.01). The blood ammonia concentrations increased soon after total hepatectomy but remained significantly lower in the rats with microencapsulated hepatocytes (P <.05). The microcapsules contained numerous viable hepatocytes with abundant bile pigments and no lymphocytic infiltration. CONCLUSIONS: Microencapsulated hepatocytes with an ultrathin polymer layer that protects them from inflammatory and lymphocytic reactions may facilitate their ability to function. In this study, 4 x 10(7) hepatocytes significantly prolonged the survival of rats that underwent hepatectomy and supported ammonia metabolism. Further development of this technique may permit its use in patients with hepatic failure.  相似文献   
84.
Because conventional methods of evaluating anorectal function do not necessarily provide good correlations between investigative results and symptoms in patients who have undergone surgery for an anorectal malformation (ARM), we recently introduced feco-flowmetry (FFM) to simulate natural anorectal evacuation. The purpose of this study was to embody significant parameters to elucidate the dynamics of anorectal activity on FFM. The parameters of FFM were compared with those of manometry and Kelly's clinical score (KCS) in 24 patients who underwent surgery for an ARM. There were three fecoflow patterns, namely, block (B) type, segmental (S) type, and flat (F) type. The B-type or S-type patterns were seen in patients classified as "clinically good." There were close relationships between the fecoflow pattern and both the operative procedure and the KCS (P = 0.01 and 0.001, respectively). Maximum fecal stream flow rate (Fmax) precisely reflected the tolerance rate of intended normal saline solution in the colorectum (TR), the evacuative rate (ER), and KCS. Fmax > 45 ml/s or TR > 70% or ER > 50% was statistically regarded as the borderline of fecal continence. Thus, the fecoflow pattern might reflect the motor activity of the pelvic floor muscle. FFM provided quantiative and qualitative evaluations concerning anorectal motor activity in patients who had undergone surgery for an ARM.  相似文献   
85.
Mesenchymal hamartoma of the liver (MHL) is an uncommon benign tumor found primarily in children younger than 2 years of age. We report a rare case of MHL with a daughter nodule and atypical histological findings in a 14-month-old girl. On admission, computed tomography, magnetic resonance imaging, and angiography showed a solid hypovascular mass with a central cystic area in the liver. Laparotomy revealed a tumor, 8 cm in size, occupying segment 5 and parts of segments 4 and 6 of the liver, and a small nodule, 10 mm in size, in segment 7. Thus, we performed a partial hepatic resection (S4–6) and tumor extirpation (S7). The histological findings of both tumors were the same, but atypical of MHL. Recent studies on the pathogenesis of this tumor have found neoplastic features such as genetic anomalies and malignant transformation. These findings suggest that the conventional approach of completely resecting the tumor whenever possible is the best treatment.  相似文献   
86.
A 57-year-old woman was hospitalized with a left renal artery aneurysm (RAA). The aneurysm measured 35 mm in diameter and was located at the renal artery bifurcation. We performed a laparoscopic nephrectomy using a retroperitoneal approach and performed an ex vivo repair of the renal artery. The reconstructed kidney was then autotransplanted at the left iliac fossa. The patient's postoperative course was uneventful. A laparoscopic nephrectomy and ex vivo repair are both considered to be effective for treating complex RAA.  相似文献   
87.
88.
We herein describe a 60-year-old Japanese man with a giant retroperitoneal liposarcoma undergoing leiomyosarcomatous differentiation. He was admitted to our hospital because of a 5-month history of dysphagia and abdominal distention. Abdominal computed tomography showed a giant tumor that occupied the entire retroperitoneal space. The majority of the mass was lipomatous and low density; both a heterogenous and solid mass were also present. A giant retroperitoneal liposarcoma was diagnosed, and tumor resection was performed. At surgery, the tumor was mostly isolated from the retroperitoneum and other organs. Histopathologically, the tumor comprised well-differentiated and dedifferentiated liposarcoma with heterologous differentiation of the leiomyosarcomatous components, which is a rare phenomenon in liposarcoma. The patient was alive 3 years after the first treatment, although he has had 3 local recurrences (approximately one recurrence yearly) and has been treated by repeated resection and radiotherapy.Key words: Retroperitoneum, Liposarcoma, Leiomyosarcomatous differentiationDedifferentiated liposarcoma (DL) is one of the most frequent sarcomas of the retroperitoneum. It is defined by the association of an atypical lipomatous tumor, namely, areas of well-differentiated liposarcoma (WDL), with a dedifferentiated component. WDL is composed of mature adipocytes and atypical stromal cells with an enlarged, hyperchromatic nucleus. Usually, the dedifferentiated part of the liposarcoma is composed of either a spindle/pleomorphic high-grade sarcoma or a mixoid/spindle cell low-grade sarcoma. The WDL component may be easily overlooked, and DL may thus be mistaken for another high-grade sarcoma. It has been reported in one study that approximately 5% of the dedifferentiated component showed heterologous differentiation, such as leiomyosarcoma, rhabdomyosarcoma, osteosarcoma, and angiosarcoma.1 A less common phenomenon is the occurrence of WDL with leiomyosarcomatous (LMS) differentiation.2 Limited to the retroperitoneum, only 8 cases of liposarcoma with LMS components have been reported.37 We herein report a case of retroperitoneal liposarcoma comprising WDL and DL, with LMS components, treated by surgical resection.  相似文献   
89.
The present case illustrates the unexpected occurrence of intradural chordomas that were simultaneously discovered in cranial and spinal locations. A 63-year-old female presented with weakness in the left upper extremity. The patient visited a local doctor and underwent brain computerized tomography (CT). CT revealed a brain tumor, and she was referred to our hospital. Brain magnetic resonance imaging (MRI) demonstrated a midline intradural retroclival tumor in addition to an intradural extramedullary mass lesion at the level of C1–C2. The patient developed a spastic gait disturbance that forced her to use a cane. She underwent laminectomy at C1–C2 along with total removal of the tumor and showed no remarkable symptoms after surgery. Histopathological examination confirmed the diagnosis of chordoma. One month after the cervical surgery, the intracranial tumor was subtotally removed in intracranial surgery via the right subtemporal approach. Histopathological data were identical to that of the cervical tumor. The patient consulted another hospital and underwent gamma-knife surgery. Her neurological examination is relatively unchanged 20 months after the cervical surgery. This case suggests that neuroradiological evaluation should also be performed for an intradural spinal chordoma when an intracranial chordoma is detected. Careful determination of the tumor responsible for the symptoms is necessary if an intradural spinal chordoma is simultaneously detected with an intracranial chordoma.  相似文献   
90.

Objective

The feasibility of multimodality therapy in patients with node-positive non-small cell lung cancer (NSCLC) requiring pneumonectomy and the role of pneumonectomy in N2 disease remain controversial. This study evaluated outcomes in patients with node-positive NSCLC undergoing pneumonectomy in a community hospital.

Methods

Perioperative and long-term outcomes of 37 patients with node-positive (pN1–2) NSCLC undergoing pneumonectomy from September 1994 to April 2010 as a clinical practice were retrospectively analyzed.

Results

Twenty patients received induction therapy, and 17 received preoperative chemoradiation (30–40 Gy). Fifteen patients and 22 patients underwent right and left pneumonectomy, respectively. A postoperative complication occurred in 8 patients. In-hospital mortality occurred in 1 patient. Induction therapy did not increase the operative risk including operative time, blood loss and postoperative complications. Nineteen patients were given a diagnosis of pN2. Although 7 bulky N2 patients and 10 multi-station N2 patients were included, 5-year overall survival was 34.3 % in pN1 and 28.0 % in pN2 (p = 0.998), respectively. Twenty-three patients received additional postoperative therapy. Five patients died within 3 months postoperatively due to distant metastases. Induction therapy and laterality did not influence survival. Extended resection, such as vagus nerve or chest wall resection, predicted an unfavorable outcome in multivariate analysis (Hazard ratio 2.81, p = 0.032).

Conclusions

The safety and acceptable long-term outcome of pneumonectomy as a general clinical practice were shown for both pN1 and pN2 patients with various preoperative or postoperative therapies. Extended resection due to the extrapleural or extranodal involvement of tumor was an unfavorable prognostic factor.  相似文献   
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