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41.
Partial tolerance in rat renal allograft recipients following multiple blood transfusions and concomitant cyclosporine 总被引:1,自引:0,他引:1
C W Hewitt K S Black J C Harman K R Beko H S Lee A P Patel D C Martin 《Transplantation》1990,49(1):194-198
Multiple prior administrations of donor-strain blood while under limited cyclosporine cover, consistently induce extensive rat renal allograft survival and transplantation tolerance. Yet it was hypothesized that some chronic rejection mechanisms were nevertheless operative since consistent but nonprogressive minor renal dysfunction was observed long-term. A histopathologic study on these putative tolerant rats was undertaken to test this hypothesis. Twenty long-term LEW recipients of BN renal allografts receiving the blood-CsA regimen were examined histopathologically at day 100 post-transplant. Sixteen control LEW recipients receiving only a BN renal allograft were studied acutely at day 7 posttransplant. The control recipients demonstrated a range of lesions consistent with previous studies on acute renal allograft rejection in the rat. However, tolerant recipients demonstrated mild-to-moderate lesions consistent with chronic mechanisms of rejection including the following: moderate focal interstitial mononuclear inflammatory cellular infiltration, with periglomerular and perivascular accumulation; occasional arteriolar luminal obliteration and glomerular atrophy; focal areas of moderate interstitial fibrosis; mild interstitial hemorrhage; mild-to-moderate tubular atrophy; and focal tubular necrosis. Previously our laboratory has documented that tissue-specific renal basement membrane antigens may be responsible for inciting this pattern of focal chronic interstitial inflammation. However, from the present histopathologic studies, it would appear likely that chronic rejection mechanisms in these recipients, which were defined as tolerant by immunologic criteria, involve both tissue-specific and MHC determinants. Therefore, induction of transplantation tolerance in these indefinite survivors is partial or incomplete. 相似文献
42.
43.
Ken Igawa Ryuji Maruyama Ichiro Katayama Kiyoshi Nishioka 《The Journal of dermatology》1997,24(5):328-331
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease. 相似文献
44.
Short-term hyperglycemia depresses immunity through nonenzymatic glycosylation of circulating immunoglobulin 总被引:7,自引:0,他引:7
Hyperglycemia accompanies a myriad of clinical conditions and causes an acceleration in the nonenzymatic glycosylation (NEG) of proteins. Since many proteins lose function when glycosylated, we assessed the effect of hyperglycemia on the function of immunoglobulin G. Twenty newborn Sprague-Dawley rats underwent splenectomy and 20, splenic mobilization alone. After 3 weeks, all animals received an intraperitoneal injection of Streptococcus pneumoniae. Twelve hours later, ten animals from each group received either control (CIG) or glycosylated (GIG) human immunoglobulin (0.3 gm/kg) intraperitoneally. Asplenic animals receiving GIG lived 28.5 hours vs. 49.6 hours for those receiving CIG (p less than 0.0001). Animals with spleens receiving GIG lived 48.2 hours vs. 51.7 hours for those receiving CIG (p = 0.03). Short-term glycosylation of immunoglobulin causes its inactivation. This may contribute to the increased risk of infection noted in hyperglycemic animals. 相似文献
45.
46.
Perioperative cardiac events in patients undergoing noncardiac surgery: a review of the magnitude of the problem, the pathophysiology of the events and methods to estimate and communicate risk 总被引:5,自引:0,他引:5
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P.J. Devereaux Lee Goldman Deborah J. Cook Ken Gilbert Kate Leslie Gordon H. Guyatt 《Canadian Medical Association journal》2005,173(6):627-634
THIS IS THE FIRST OF 2 ARTICLES EVALUATING cardiac events in patients undergoing noncardiac surgery. In this article, we review the magnitude of the problem, the pathophysiology of these events, approaches to risk assessment and communication of risk. The number of patients undergoing noncardiac surgery worldwide is growing, and annually 500 000 to 900 000 of these patients experience perioperative cardiac death, nonfatal myocardial infarction (MI) or nonfatal cardiac arrest. Although the evidence is limited, a substantial proportion of fatal perioperative MIs may not share the same pathophysiology as nonoperative MIs. A clearer understanding of the pathophysiology is needed to direct future research evaluating prophylactic, acute and long-term interventions. Researchers have developed tools to facilitate the estimation of perioperative cardiac risk. Studies suggest that the Lee index is the most accurate generic perioperative cardiac risk index. The limitations of the studies evaluating the ability of noninvasive cardiac tests to predict perioperative cardiac risk reveals considerable uncertainty as to the role of these popular tests. Similarly, there is uncertainty as to the predictive accuracy of the American College of Cardiology / American Heart Association algorithm for cardiac risk assessment. Patients are likely to benefit from improved estimation and communication of cardiac risk because the majority of noncardiac surgeries are elective and accurate risk estimation is important to allow informed patient and physician decision-making. 相似文献
47.
Kazumasa Miyake Atsushi Tatsuguchi Mikiko Tachibana Masanobu Kusunoki Yoko Shinji Kei Shinoki Tetsuro Hiratsuka Kazuhiro Nagata Hitoshi Nishigaki Seiji Futagami Ken Wada Taku Tsukui Toshiro Yoshiyuki Akira Tokunaga Takashi Tajiri Choitsu Sakamoto 《Digestive endoscopy》2004,16(2):172-175
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia. 相似文献
48.
Yoshito Tomimaru Ken Kodama Jiro Okami Kazuyuki Oda Koji Takami Masahiko Higashiyama 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(5):193-198
Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary
resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with
pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had
never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients
were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with
left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right
thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic
patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three
of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial
effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial
effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198) 相似文献
49.
HMG-CoA reductase inhibitor cerivastatin prolonged rat cardiac allograft survival by blocking intercellular signals. 总被引:11,自引:0,他引:11
Hitoshi Horimoto Yasunari Nakai Ken ich Nakahara Yukiya Nomura Shigetoshi Mieno Shinjiro Sasaki 《The Journal of heart and lung transplantation》2002,21(4):440-445
BACKGROUND: The development of atherosclerotic cardiovascular complications caused by hyperlipidemia is a common and serious problem for long-term survivors of organ transplantation. However, adhesion molecules such as intercellular adhesion molecule (ICAM)-1 and lymphocyte function-associated antigen (LFA)-1 are involved in allograft rejection, possibly by providing costimulatory signals. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor cerivastatin has been shown to suppress ICAM-1 expression in acute inflammatory responses. METHODS: In this study, we evaluated the immunosuppressive effects of cerivastatin in rat cardiac allografts. The hearts of Fischer rats were transplanted heterotopically into Lewis rats. Cerivastatin (2 mg/kg) was administrated intraperitoneally to recipients for 7 consecutive days from the day before transplantation. RESULTS: Graft survival in the cerivastatin-treated group (n = 8) was significantly longer than in controls (n = 10) (24.6 +/- 2.2 days vs 10.2 +/- 1.3 days, p < 0.05). Mixed lymphocyte reaction (MLR) showed that on Day 8 after grafting, the proliferative response of alloreactive T cells against F344 alloantigen in cerivastatin-treated rats was significantly more suppressed than in Lewis rats. The Interleukin-2 concentration of supernatant in MLR cultures in the cerivastatin-treated group was lower than in the control group. Immunohistochemical analysis showed that the percentage of CD4-positive cells to infiltrating mononuclear cells was less prominent in the cerivastatin-treated group (9.8% +/- 2.2%) than in the control group (20.9% +/- 3.2%). CONCLUSIONS: The HMG-CoA reductase inhibitor cerivastatin effectively suppressed acute graft rejection, possibly by blocking intercellular signals via ICAM/LFA-1, and cerivastatin may be a candidate for treating patients with hyperlipidemia who undergo organ transplantation. 相似文献
50.
CT appearance of cervical lipoblastoma 总被引:1,自引:0,他引:1
W C Black J W Burke P S Feldman C M Johnson S Swanson 《Journal of computer assisted tomography》1986,10(4):696-698
We describe a case of lipoblastoma causing respiratory symptoms in an infant, where CT was useful in establishing the diagnosis and demonstrating the extent of involvement so that complete surgical resection could be planned. 相似文献