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41.
Kousuke Marutsuka Yoshihiro Hasui Yujiro Asada Seiji Naito Yukio Osada Akinobu Sumiyoshi 《Clinical & experimental metastasis》1995,13(2):116-122
Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID50 = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis. 相似文献
42.
H K Naito 《American journal of clinical pathology》1988,90(3):358-361
To help reduce the prevalence of elevated blood cholesterol levels in adult Americans, the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health (NIH) launched the National Cholesterol Education Program (NCEP) in 1985. The program aims to raise awareness and understanding about high blood cholesterol levels as a risk for coronary artery disease (CAD) and the benefits of lowering cholesterol levels as a means of preventing CAD. This national awareness program is aimed at three target groups: (1) health professions, (2) the public and patient, and (3) the community. This article summarizes the highlights of the NHLBI NCEP Laboratory Standardization Panel's (LSP) report and the Adult Treatment Panel's (ATP) report. The LSP report emphasized the need for accurate and precise cholesterol measurements and evaluated the current state of reliability of these measurements. It also described the degree to which accurate and precise cholesterol measurements are possible based on currently available instrumentation, reagents, and methods. The LSP report made a series of broad recommendations designed to improve laboratory performance that are discussed in this article. The ATP's report established criteria that define candidates with high blood cholesterol levels who should receive medical intervention and provided guidelines on how to detect, set goals, treat, and monitor these patients over time. For the first time in medical history there is a consensus by leading experts in the field on the measurement, detection, and treatment of patients with hypercholesterolemia. The detailed recommendations of the LSP and ATP should have a major impact on 40 million adults in the United States and may save approximately 300,000 lives annually. 相似文献
43.
Immunoglobulin G response to subgingival gram-negative bacteria in human subjects 总被引:6,自引:6,他引:6 下载免费PDF全文
Serum and gingival crevicular fluid from normal healthy adults and patients with periodontitis were screened for immunoglobulin G antibodies to antigens from Bacteroides gingivalis 381, Bacteroides intermedius 24, Bacteroides loescheii ATCC 15930, Fusobacterium nucleatum ATCC 25586, Eikenella corrodens 1073, Actinobacillus actinomycetemcomitans ATCC 29522, and Capnocytophaga sp. strain M-12. Immunoglobulin G antibody titers to the antigens were measured by an enzyme-linked immunosorbent assay. The antibody levels to B. gingivalis in serum and gingival crevicular fluid were significantly higher in the samples from patients with periodontitis than in samples from healthy individuals. Although there were individual differences within patient groups, a positive correlation (P less than 0.01) was found between the serum immunoglobulin G levels to B. gingivalis and the development of periodontitis. The antibodies to F. nucleatum (P less than 0.05), E. corrodens (P less than 0.05), and A. actinomycetemcomitans were slightly higher in patients with periodontitis than in normal subjects. There were no remarkable differences between the two groups in titers to B. intermedius, B. loescheii, and Capnocytophaga sp. 相似文献
44.
Hideo Sakuma Naoyoshi Mori Mizu Kojima Takeo Saito Fuminori Tachibana Makoto Naito 《Pathology international》1984,34(5):1157-1166
A case with lymphadenopathy of the left side of the neck in a 38-year-old male is described. He had a history of several relapses of about 10 years duration. Swollen lymph nodes were histologically similar to those of the hyaline-vascular type of Castleman's disease, but contained clear-cut lymph sinus and a sheet-like proliferation of plasma cells. Lymph follicles showed proliferation and atrophic germinal centers, in which cellular hypertrophy in the wall of ramifying small blood vessels, called angiosclerosis, was frequently encountered. During its progress, the patient developed plasmacytoma of the lymph nodes with varied clinical manifestations such as polyneuropathy, disturbance of gait, unusual perspiration, hirsuitism, gynecomastia, bilateral papilledema, and albumino-cytologic dissociation in cerebrospinal fluid. 相似文献
45.
46.
Watanabe T Hasegawa G Yamamoto T Hatakeyama K Suematsu M Naito M 《Archives of histology and cytology》2003,66(2):155-162
Heme oxygenase (HO), the heme-degrading enzyme, plays an important role in heme catabolism. Among three isozymes, HO-1 is an inducible form expressed mainly in macrophages. In rat ontogeny, HO-1 immunoreactivity was detected in mononuclear cells in the yolk sac at 10 days of gestation. HO-1-expressing cells were then detected in the fetal liver and their numbers increased during the gestational period. The numbers of HO-1-positive cells and HO-1 mRNA levels in the liver peaked at 18 days of gestation. Most of the macrophages expressed both HO-1 and a macrophage scavenger receptor. Macrophages in the fetal liver showed marked hemophagocytosis. Macrophages in the lung, spleen, bone marrow, and other tissues also expressed HO-1. HO-1 immunoreactivity was also observed in syncytial cells of the chorionic villi, the endodermal layer of the yolk sac, and renal tubules of the fetus. Intestinal mucosal epithelial cells expressed HO-1 after birth. These findings imply that HO-1 is crucial for macrophages in heme catabolism from an early stage of ontogeny. HO-1 expression in non-macrophagic cells may be required for other purposes such as protection from oxidative stress and various stimuli. 相似文献
47.
48.
Aoi W Naito Y Sakuma K Kuchide M Tokuda H Maoka T Toyokuni S Oka S Yasuhara M Yoshikawa T 《Antioxidants & redox signaling》2003,5(1):139-144
Dietary antioxidants may attenuate oxidative damage from strenuous exercise in various tissues. Beneficial effects of the antioxidant astaxanthin have been demonstrated in vitro, but not yet in vivo. We investigated the effect of dietary supplementation with astaxanthin on oxidative damage induced by strenuous exercise in mouse gastrocnemius and heart. C57BL/6 mice (7 weeks old) were divided into groups: rested control, intense exercise, and exercise with astaxanthin supplementation. After 3 weeks of exercise acclimation, both exercise groups ran on a treadmill at 28 m/min until exhaustion. Exercise-increased 4-hydroxy-2-nonenal-modified protein and 8-hydroxy-2'-deoxyguanosine in gastrocnemius and heart were blunted in the astaxanthin group. Increases in plasma creatine kinase activity, and in myeloperoxidase activity in gastrocnemius and heart, also were lessened by astaxanthin. Astaxanthin showed accumulation in gastrocnemius and heart from the 3 week supplementation. Astaxanthin can attenuate exercise-induced damage in mouse skeletal muscle and heart, including an associated neutrophil infiltration that induces further damage. 相似文献
49.
Shigeo Nagasaka Shigeki Taniguchi Yoshio Nakayama Hidehito Sakaguchi Kazuhiko Nishizaki Hiroshi Naito Hiroyuki Morioka 《Cardiovascular pathology》2005,14(2):70-79
BACKGROUND: Recent reports have suggested that cryopreservation reduces the immunogenicity of donor tissue. The immunomodulation by cryopreservation might influence on the tissue durability after xenotransplantation. We investigated the in vivo morphologic changes in cryopreserved xenograft (CXG) heart valves. MATERIAL AND METHOD: We transplanted a fresh (fresh xenograft; FXG) and a cryopreserved (CXG) porcine aortic root and a cryopreserved canine (cryopreserved allograft; CAG) aortic root into the abdominal aorta of a dog without any immunosuppressive agents. Explanted grafts on the 21st to 49th days after implantation were analyzed morphologically with light microscopy using some special stains, immunohistochemical analysis, and scanning electron microscopy (SEM). RESULT: Light microscopy showed the absence of smooth muscle cells in the media of the aorta in any group after transplantation. FXG valves did not maintain any cellularity after transplantation. CXG valves contained cellular infiltration in themselves. CAG valves contained numerous fibroblasts, which showed the maintenance of tissue integrity without allowing cellular infiltration. The structure of elastic fibers was well maintained, even in the part of CXG valve with cellular infiltration. Immunohistochemical studies documented the infiltration of T lymphocytes in CXG valves that were labeled by anti-CD3 antibodies. SEM demonstrated that no endothelia were seen on the surface of the valves in any group after transplantation. CONCLUSION: We concluded that the cryopreservation method might provide an immunomodulation of xenogeneic heart valves for transplantation. 相似文献
50.
This study analyzed the expression of anti-islet autoantibodies and HLA-DR and -DQ genotypes in Korean children with type 1 diabetes mellitus (T1DM). The positivity of the anti-ICA512, anti-GAD65, and anti-insulin autoantibodies in the newly onset T1DM patients (n = 15) was 66.7%, 86.7%, and 46.7%, respectively, and all of them had one or more of the autoantibodies. HLA analysis showed higher frequencies of HLA-DRB1*0301, *0405, *09012 and -DQB1*0201, *0401, *03032 alleles in T1DM patients compared to controls (P(c) < 0.05). Because HLA-DQB1*0401, *03032 alleles carry aspartic acid at position 57 of DQB, susceptibility to T1DM in Korean children was not related to the presence of aspartic acid at position 57 of DQB1 locus. We suggest this unique HLA-DR, -DQ allele distribution might be an important factor for the low incidence of T1DM in Korea, and the combined anti-islet autoantibody assays could be valuable screening markers for the early detection of T1DM in Korea. 相似文献