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71.
Generation of a transgenic animal model of hyperthyroid Graves' disease   总被引:6,自引:0,他引:6  
Graves' disease (GD) is an organ-specific autoimmune disease characterized by hyperthyroidism. Agonistic anti-thyrotropin receptor antibodies (thyroid-stimulating antibodies, TSAb), which mimic the thyrotropin (TSH) action, are thought to cause GD. The precise immunological mechanism of TSAb production, however, remains elusive. Previous immunization approaches using TSH receptor led to transient hyperthyroidism, but did not seem sufficient for comprehensive understanding of the development of autoimmune responses. To create GD-related autoimmunity in mice, we here generated TSAb-transgenic mice in which a patient-derived TSAb is expressed in B cells. Expression of the human TSAb in mice resulted in various manifestations of hyperthyroidism including increased free thyroxine levels with concomitantly decreased TSH levels, increased thyroid uptake of technetium pertechnetate, hyperthermia and thyroid hyperplasia. We found a correlation between the serum levels of human TSAb immunoglobulin and free thyroxine. In addition, conventional B cells expressing the TSAb were partially deleted in the periphery while B1 cells expressing the TSAb persisted and accumulated in the peritoneal cavity, a finding consistent with previous demonstrations that the maintenance of B1 cells plays an important role in the development of autoimmune diseases. Thus, our transgenic mouse may provide a novel and useful animal model for elucidating the pathogenesis and pathophysiology of GD.  相似文献   
72.
Long-term survivors of acquired aplastic anemia (AA) have an increased risk of developing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) after immunosuppressive therapy (IST). It is uncertain whether the increased survival time simply discloses the natural history of AA as a premalignant disease or whether secondary disease is related to the therapy itself. Between November 1992 and September 1997, 113 AA children with normal cytogenetics at diagnosis were treated with IST using antithymocyte globulin, cyclosporin, and danazol with or without granulocyte colony-stimulating factor (G-CSF). We assessed risk factors for developing MDS/AML by Cox proportional hazards models. Twelve of 113 patients developed MDS between 9 and 81 months following the time of diagnosis, giving a cumulative incidence of 13.7 +/- 3.9%. The following cytogenetic abnormalities were observed at the time of diagnosis of MDS: monosomy 7 (6 patients), monosomy7/trisomy21 (1 patient), trisomy 11 (1 patient), del (11) (9?:14) (1 patient), add (9q) (1 patient), add 7 (q 32) (1 patient), and trisomy 9 (1 patient). The number of days of G-CSF therapy and nonresponse to therapy at 6 months were statistically significant risk factors by multivariate analysis. The present study suggests a close relationship between long-term use of G-CSF and secondary MDS in nonresponders to IST.  相似文献   
73.
74.
BACKGROUND: Crush syndrome has been described as extensive muscle damage, leading to acute renal failure. The aim of this study was to evaluate the possible role of nitric oxide, tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) in crush syndrome. PATIENTS AND METHODS: A total of 17 patients suffering from crush syndrome, 7 patients without crush syndrome and 10 healthy controls were enrolled in the study. Plasma nitrate, TNF-alpha, IL-1 beta levels and biochemical parameters were measured. RESULTS: All patients with crush syndrome demonstrated acute renal failure. Plasma nitrate levels were elevated significantly in the crush syndrome patients compared with patients without crush syndrome (33.5 +/- 20.1 vs. 15.3 +/- 5 micromol/l, p=0.014). There was no significant difference in TNF-alpha and IL-1 beta levels between control and patient groups. CONCLUSION: Increased plasma nitrate levels in the crush syndrome may be related either to the elevated production of NO or the diminished excretion of nitrate or both.  相似文献   
75.
BACKGROUND: The present study aimed to clarify the predisposing factors for postoperative infectious complications after less invasive surgery. METHODS: A total 150 surgical patients were placed in either group H (operative blood loss > or = 500 mL) or group L (<500 mL). The patients' background factors and postoperative inflammatory responses were assessed. RESULTS: The operating time was an independent risk factor for infectious complication in group H. In contrast, allogenic blood transfusion was the only significant risk factor for infection in group L. In the patients who received blood transfusion, exaggerated postoperative interleukin-6 response was found in group H, whereas an increased consumption of interleukin-6 soluble receptor with resultant induction of immunosuppressive acidic protein (IAP) were found in group L. CONCLUSIONS: Perioperative blood transfusion may predominantly contribute to increased susceptibility to infection after less invasive surgery through increased affinity of interleukin-6 soluble receptor and enhanced IAP response.  相似文献   
76.
BACKGROUND: Interleukin (IL)-18 is a novel cytokine that has recently been characterized as an inducer of interferon-gamma (IFN-gamma). The aim of this study was to investigate the clinical significance of peritoneal IL-18 concentrations in patients with peritonitis. METHODS: We measured IL-18, IFN-gamma, and IL-10 concentrations in the peritoneal fluid of 28 patients undergoing laparotomy for peritonitis. Correlations between the peritoneal cytokine concentrations and the severity of illness determined by systemic inflammatory response syndrome (SIRS) criteria, Acute Physiological and Chronic Health Evaluation II (APACHE II) score, peritoneal fluid bacterial culture results, subsequent development of organ failure, and length of hospital stay were assessed. RESULTS: Interleukin-18 concentration was significantly increased in patients who developed SIRS, in those with culture-positive peritonitis, and in those who developed organ failure, as compared with the other patients. Interleukin-10 concentration, which was also significantly increased in patients with culture-positive peritonitis, showed a close correlation with IL-18 concentration. Although a weak correlation was observed between IL-18 and IFN-gamma concentrations, IFN-gamma concentrations did not show any association with patients' clinical parameters. However, the IFN-gamma/IL-18 ratio was significantly lower in patients with an APACHE II >/=10, and in those with culture-positive peritonitis, as compared with the other patients. BACKGROUND: Peritoneal IL-18 concentration increased in response to intraperitoneal bacterial infection and seemed to reflect the severity of peritonitis. However, the capacity of IL-18 to produce IFN-gamma may be altered depending on the severity of peritonitis.  相似文献   
77.
BACKGROUND: Satisfactory intermediate and long-term results of periacetabular rotational osteotomy for early osteoarthritis secondary to dysplasia of the hip have been reported for patients in the third and fourth decades of life. The purpose of the present study was to examine the usefulness of rotational acetabular osteotomy in patients older than forty-six years of age. METHODS: A retrospective review of two groups of patients who had been treated with a rotational acetabular osteotomy was conducted. The older group consisted of twenty-four patients (twenty-six hips) with early-stage osteoarthritis who had a mean age at the time of surgery of 50.9 years (range, forty-six to fifty-eight years) and a mean duration of follow-up of 8.2 years (range, five to thirteen years), and the younger group consisted of sixty patients (sixty-three hips) who had a mean age at the time of surgery of 34.4 years (range, thirteen to forty-five years) and a mean duration of follow-up of 8.3 years (range, five to fourteen years). Clinical follow-up was based on the system of Merle d'Aubigne and Postel. The center-edge angle, acetabular roof angle, and head lateralization index were measured on radiographs made preoperatively, postoperatively, and at the time of follow-up. Preoperative and postoperative joint congruencies were classified into four grades. RESULTS: Preoperatively, the mean Merle d'Aubigne clinical score was 13.9 points in the older group and 14.1 points in the younger group. In both groups, this score improved significantly to a mean postoperative follow-up score of 16.6 points (p < 0.0001), with no significant difference between the two groups. The mean center-edge angle improved from 3.2 degrees preoperatively to 34 degrees postoperatively (p < 0.0001) in the older group and from -2.1 degrees preoperatively to 34 degrees postoperatively (p < 0.0001) in the younger group. The mean acetabular roof angle improved from 29 degrees to 5.9 degrees (p < 0.0001) in the older group and from 31 degrees to 2.9 degrees (p < 0.0001) in the younger group. The mean head lateralization index improved from 0.67 to 0.64 (p < 0.01) in the older group and from 0.66 to 0.61 (p < 0.0001) in the younger group. Progression of osteoarthritis was observed radiographically at the time of follow-up in five hips in the older group and in four hips in the younger group. Kaplan-Meier survivorship analysis, with radiographic progression of osteoarthritis as the end point, predicted a ten-year survival rate of 70.0% in the older group and 93.7% in the younger group; this difference was not significant, with the numbers available (p = 0.062, log-rank test). CONCLUSIONS: Our results indicate that rotational acetabular osteotomy for elderly patients can prevent progression of osteoarthritis (as indicated by a survival rate of 70% at ten years) and that in selected cases it is worthwhile at least as a temporizing operation.  相似文献   
78.
We have previously shown that a novel hydrophobized polysaccharide/oncoprotein complex vaccine can induce immune responses against the HER2/neu/c-erbB2 (HER2) expressing tumors. Bone marrow-derived dendritic cells (DCs), as antigen presenting cells (APCs), are the first candidates for presentation of tumor antigens. The aim of this study was to see whether DCs are able to elicit antigen specific host immune responses by stimulating the proliferation of T cells after exposure to cholesteryl group bearing pullulan (CHP) and HER2 protein complex. Vaccination by CHP-HER2 complex was as effective as cholesteryl group bearing mannan (CHM) and HER2 complex on which we reported previously. Immunization of mice with HER2 expressing CMS17HE tumor cells generated both CD4+ T cells and CD8+ T cells reactive with CHP-HER2 complex pretreated DCs. In addition, immunization with either CHP-HER2 complex or HER2 protein alone could also generate both CD4+ T cells and CD8+ T cells specifically reactive with CHP-HER2 complex pretreated DCs. The complete rejection of tumors occurred when immunization with CHP-HER2 complex pretreated DCs was started 10 days after tumor inoculation. Therefore, bone marrow-derived DCs pretreated with hydrophobized polysaccharide/oncoprotein complex are a powerful tool for enhancing the effectiveness of oncoprotein for anti-tumor vaccination, opening new options for immune cell therapy.  相似文献   
79.
In an autopsy case of galactosialidosis, GM3, GM2, GM1, and GD1a were accumulated in sympathetic and spinal ganglia and grey matter of the spinal cord. Especially, the accumulations of GM3 and GM2 amounted to 41- and 86-fold increases in sympathetic ganglia, respectively, as compared to normal controls. In addition LacCer, GA2 and GA1 were accumulated in sympathetic and spinal ganglia. The accumulations of GM3 and GD1a are considered to be the result of defective lysosomal sialidase activity and the accumulation of GM1, LacCer and GA1 is also considered to be due to decreased beta-galactosidase activity in this disorder. To better understand the possible mechanism of GM2 accumulation, we determined the activity of GM2 synthesizing enzyme (GM3:UDP-GalNAc transferase), as well as hexosaminidase activity, in sympathetic ganglia, but they did not change. Abnormal ganglioside and neutral glycosphingolipid metabolism, as well as sialyloligosaccharide and sialylglycoprotein metabolism, may be involved in the pathogenesis of this disorder.  相似文献   
80.
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