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41.
Recently we have reported cases of demyelinating inflammatory neuropathy showing elevated titers of anti-GD3 antibodies, which occurs rarely in Guillain-Barré syndrome. To examine the correlation between the anti-GD3 antibody titer and Campylobacter jejuni infection, we sensitized female Lewis rats with lipopolysaccharides (LPSs) from serotype HS19 of C. jejuni and examined changes in nerve conduction velocity and nerve conduction block (P/D ratio). After 16 weeks of sensitization, animals revealed decreases of nerve conduction velocity and conduction block (P/D ratio) and high titer of anti-GD3 antibodies. These anti-GD3 antibodies also blocked transmission in neuromuscular junctions of spinal cord-muscle cells cocultures. The GD3 epitope was verified to be located on the Schwann cell surface and nodes of Ranvier in rat sciatic nerve. To determine the target epitope for GD3 antibodies in causing nerve dysfunction, the LPS fraction containing the GD3 epitope was purified from the total LPS by using an anti-GD3 monoclonal antibody-immobilized affinity column. Subsequently, chemical analysis of the oligosaccharide portion was performed and confirmed the presence of a GD3-like epitope as having the following tetrasaccharide structure: NeuAcalpha2-8NeuAc2-3Galbeta1-4Hep. Our data thus support the possibility of a contribution of GD3 mimicry as a potential pathogenic mechanism of peripheral nerve dysfunction.  相似文献   
42.
BACKGROUND: Propofol-anesthesia administerd using target-controlled infusion (TCI) has been proposed for cardiac surgery. But, moderate target concentration of propofol during induction using TCI has not been studied in detail. METHODS: Thirty patients scheduled for cardiac surgery under cardiopulmonary bypass (CPB) and TCI propofol anesthesia were randomly divided into two groups to receive a computer-controlled infusion of propofol with target concentrations of 1.5 or 2.0 micro/g x ml(-1) [1.5 microg x ml(-1) group (n=15) and 2.0 microg x ml(-1) group (n=15)]. Mean arterial pressure (MAP), heart rate (HR) and bispectral index scale (BIS) values were recorded at 5 time points during induction of anesthesia. RESULTS: MAP was significantly lower in 2.0 microg x ml(-1) group compared with 1.5 microg x ml(-1) group. In both groups, a rise of BIS value did not occur during tracheal intubation. CONCLUSIONS: We have demonstrated that propofol TCI at a target concentration of 1.5 microg x ml(-1) is effective for hemodynamic stability during induction of anesthesia in patients for cardiac surgery under CPB.  相似文献   
43.
An epidermoid cyst is a common occurrence in the skin. Such a cyst occurring in the retrorectal space, however, is extremely rare. We herein present a case of retrorectal epidermal cyst in a 67-year-old Japanese woman. She reported no symptoms and a perirectal mass behind the lower rectum was accidentally detected by computed tomography (CT). Contrast CT and magnetic resonance imaging revealed a cystic mass (76 x 70 x 63 mm) with a slightly enhanced thin wall which was attached to the lower rectum. The patient underwent surgery via a posterior approach. The mass was exposed after an excision of subcutaneous fat and was firmly adhered to the anal sphincter muscle. The cystic mass was completely removed without a proctectomy. Histologically, the cyst was diagnosed to be an epidermoid cyst. The postoperative course was uneventful, and the patient was discharged on postoperative day 9. A diagnosis of retrorectal cystic tumor is difficult, and a complete resection is necessary for the treatment of such tumors.  相似文献   
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Background

Secretory immunoglobulin A (s-IgA) plays an important role in both gut and systemic immunity. This study aimed to investigate the production of s-IgA resulting from a CO2 pneumoperitoneum compared with a laparotomy.

Methods

Using enzyme-linked immunosorbent assays, s-IgA in stool, malondialdehyde (MDA), and Toll-like receptor 4 (TLR4) in the ileal tissue were evaluated as markers for gut and systemic immune responses in an animal model. The rats were randomly divided into (i) anesthesia-only as the control group; (ii) laparotomy-only as the open group; and (iii) CO2 pneumoperitoneum-only as the pneumoperitoneum group. To evaluate the gut immune system in a time-dependent manner, each group was further divided into short- and long-time subgroups.

Results

s-IgA levels did not increase in the open group but significantly increased in the pneumoperitoneum group compared with the control group (p < 0.05). In addition, s-IgA levels in the long-time subgroup significantly increased compared with the short-time subgroup of the pneumoperitoneum group (p < 0.05). TLR4 levels steeply and gradually increased in the open and pneumoperitoneum groups, respectively. MDA levels in the pneumoperitoneum group increased during the early phase and were significantly higher than those in the open group at 24 h (p < 0.05).

Conclusions

This study demonstrated that s-IgA levels in stool increased in the pneumoperitoneum group compared with the open group, suggesting that CO2 pneumoperitoneum may cause transitory damage to the intestinal mucosa.  相似文献   
47.
To evaluate laparoscopy-assisted Billroth-I gastrectomy (LADG), we examined the outcome of its use over the last 10 years. From December 1991 to December 2001, 116 patients with early gastric cancer underwent LADG in the surgical department of Oita Medical University and Koga hospital by the same surgical staffs. An operation record and clinical sheets were reviewed to obtain the operative findings, clinical course, and pathologic findings of resected specimens to evaluate the usefulness of LADG in the management of early gastric cancer. In all LADG procedures, regional lymph nodes dissection (D1+alpha) was successfully performed using laparoscopy. The mean operative duration and blood loss were 234 minutes and 139 mL, respectively. There were only four major complications, including pneumonia, leakage of anastomosis, pancreatic injury, and anastomotic stenosis, but all these cases were successfully treated conservatively. The mean length of postoperative stay was 16.3 +/- 2.5 days. All patients except one, who died not of cancer but of cerebral bleeding, were alive without recurrence or port-site metastasis during mean follow-up period of 45 months. We successfully performed 116 LADG procedures over 10 years. This procedure is recommended for the treatment of patients with early gastric cancer because of the associated good prognosis and several benefits, including less invasiveness and early recovery.  相似文献   
48.
100 multivisceral transplants at a single center   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The objective of this study was to summarize the evolution of multivisceral transplantation over a decade of experience and evaluate its current status. SUMMARY BACKGROUND DATA: Multivisceral transplantation can be valuable for the treatment of patients with massive abdominal catastrophes. Its major limitations have been technical and rejection of the intestinal graft. METHODS: This study consisted of an outcome analysis of 98 consecutive patients who received multivisceral transplantation at our institution. This represents the largest single center experience to date. RESULTS: The most common diseases in our population before transplant were intestinal gastroschisis and intestinal dysmotility syndromes in children, and mesenteric thrombosis and trauma in adults. Kaplan Meier estimated patient and graft survivals for all cases were 65% and 63% at 1 year, 49% and 47% at 3 years, and 49% and 47% at 5 years. Factors that adversely influenced patient survival included transplant before 1998 (P = 0.01), being hospitalized at the time of transplant (P = 0.05), and being a child who received Campath-1H induction (P = 0.03). Among 37 patients who had none of these 3 factors (15 adults and 22 children), estimated 1- and 3-year survivals were 89% and 71%, respectively. Patients transplanted since 2001 had significantly less moderate and severe rejections (31.6% vs 67.6%, P = 0.0005) with almost half of these patients never developing rejection. CONCLUSIONS: Multivisceral transplantation is now an effective treatment of patients with complex abdominal pathology. The incidences of serious acute rejection and patient survival have improved in the most recent experience. Our results show that the multivisceral graft seems to facilitate engraftment of transplanted organs and raises the possibility that there is a degree of immunologic protection afforded by this procedure.  相似文献   
49.
BACKGROUND: An extended transsphenoidal approach allowed for direct midline exposure of the parasellar structures such as the hypothalamic-pituitary axis and the third ventricle. To evaluate the capability of this approach for removal of suprasellar craniopharyngiomas, surgical outcomes were retrospectively analyzed. METHODS: During a 9-year period, 20 consecutive patients with suprasellar craniopharyngioma underwent transsphenoidal tumor resection. The average follow-up period was 55 months. No patient had a purely intrasellar tumor, 9 had prechiasmatic tumors, 9 had retrochiasmatic tumors, and 2 had purely intraventricular tumors. RESULTS: Total resection was achieved in 86% of operations. Even in mostly intraventricular cases, a transsphenoidal trans-lamina terminalis approach afforded complete resection. Visual improvement and preservation of the pituitary stalk were achieved in 84% and 95% of cases, respectively. New postoperative deterioration of pituitary function occurred in about 65% of cases, and no patient resolved their preoperative hormonal disturbance after surgery. The overall percentage of patients with diabetes insipidus increased to 61% postoperatively from 11% preoperatively. Nonendocrinologic surgical complications were observed: worsening of vision in 3 patients, hyperphagia in 3 patients, short-term memory loss in 2 patients, and cerebrospinal fluid leakage in 3 patients. Recurrence after total resection occurred in 2 (11%) patients with retrochiasmatic tumors. CONCLUSIONS: Reasonable surgical results in this study suggest that the extended transsphenoidal approach is safe and effective for removal of craniopharyngiomas. Although preservation of the pituitary stalk can be achieved in a high percentage of patients, postoperative endocrinopathy still remains as a significant problem after radical removal of the craniopharyngioma.  相似文献   
50.
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.  相似文献   
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