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41.
Abe S Takizawa H Sugawara I Kudoh S 《American journal of respiratory cell and molecular biology》2000,22(3):296-303
We devised a new in vitro cell exposure system to freshly generated diesel exhaust (DE), different from conventional in vitro culture systems, to examine the effects of DE on human epithelial cells. Using this system, we investigated the effects of DE on cytokine gene expressions in BET-1A human bronchial epithelial cells. DE significantly decreased [(3)H]thymidine incorporation into BET-1A cells. DE had a significant stimulatory effect on interleukin (IL)-8 release to a marked degree. IL-8 and transforming growth factor (TGF)-beta1 messenger RNA (mRNA) expression were induced by DE in a time-dependent manner. The gas obtained by filtration of DE alone did not show a sustained increase in IL-8 protein levels and showed no induction of IL-8 mRNA, suggesting that DE particles (DEPs) play an important role in the induction of IL-8 at both mRNA and protein levels. Antioxidants, pyrrolidine dithiocarbamate, and N-acetyl-L-cysteine significantly inhibited IL-8 mRNA and protein levels by BET-1A cells. These results indicate that freshly generated DEPs may be important in the induction of cytokines such as IL-8 and TGF-beta1 relevant to allergic airway inflammation. 相似文献
42.
Clinical significance of a highly sensitive enzyme immunoassay of hepatitis B surface antigen using a novel electron spin resonance technique. 总被引:3,自引:0,他引:3
Masanori Aoki Takafumi Saito Hisayoshi Watanabe Taku Matsuo Koji Saito Hitoshi Togashi Sumio Kawata Kazuyoshi Ishikawa Masaaki Aoyama Hitoshi Kamada Haruhide Shinzawa 《Journal of medical virology》2002,66(2):166-170
We developed a highly sensitive enzyme immunoassay (EIA), the p-AP/HHTIO method, that detects serum hepatitis B surface antigen (HBsAg) by measuring stabilized nitroxide radicals using a novel electron spin resonance technique [Matsuo et al. (1998) Free Radic Biol Med 25:929-935]. To demonstrate the clinical significance of this method and to reveal occult hepatitis B virus (HBV) infection in patients, we used the method to analyze serum samples of 30 patients with acute or fulminant hepatitis who were negative for HBsAg by standard EIA, and those of seven chronic HBV carriers who became negative for HBsAg during a follow-up period by standard EIA. We also examined serum HBV DNA by amplification of the HBV S gene, using the polymerase chain reaction (PCR) technique. The p-AP/HHTIO method showed that 9 of 20 (45%) patients with acute hepatitis and 2 of 10 (20%) with fulminant hepatitis were positive for HBsAg; PCR detected HBV DNA in these HBsAg-positive patients. Antibody against hepatitis B core antigen was detected in one patient with fulminant hepatitis. The p-AP/HHTIO method demonstrated prolonged seropositivity of HBsAg even after standard EIA showed a loss of HBsAg in all seven HBV carriers. Our p-AP/HHTIO method is useful for screening and diagnosing HBV infection in patients with liver diseases who are negative for conventional HBV-related serological markers. 相似文献
43.
Kazuo Umetsu Isao Yuasa Takao Yamashita Susumu Saito Tomio Yamaguchi Srinama B. Ellepola Takafumi Ishida Tsuneo Suzuki 《Journal of human genetics》1989,34(3):195-202
The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1
*
15 in Thai,ORM1
*
16 in Paraguayan,ORM2
*
21 andORM2
*
22 in Sri Lankan. 相似文献
44.
A Masunaga T Oka H Nakamura K Kinoshita T Yamashita I Sugawara S Itoyama 《Acta pathologica japonica》1992,42(12):916-922
A case of intrauterine tumor in a 62-year-old Japanese woman is presented. It was thought initially that this was a case of uterine tumor resembling an ovarian sex cord tumor. To examine the cytological features of the tumor cells, electron microscopical and immunohistochemical studies were done, and a hormone assay of the tumor tissue was performed. The tumor cells were rich in rough endoplasmic reticulum (rER), mitochondria and microfilaments. Some tumor cells tended to form glandular patterns, but these epithelial elements were frequently scattered among fibrous stromal elements. Though many tumor cells with an epithelial appearance possessed a large quantity of cytokeratin and vimentin, they did not secrete estradiol, progesterone, testosterone or human chorionic gonadotropin. This case was finally diagnosed as an intramural uterine stromal tumor with epithelial differentiation after taking all the available data into consideration. This would be classified as an endometrial stromal tumor with epithelial elements, recently proposed and named by Clement and Scully. 相似文献
45.
Matsuzaki Y Sato K Sugawara K Takashita E Muraki Y Morishita T Kumagai N Suzuki S Hongo S 《Journal of clinical microbiology》2005,43(2):993-995
An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown. 相似文献
46.
Masai T Taniguchi K Kuki S Yokota T Yoshida K Yamamoto K Matsuda H 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2003,49(1):108-111
Although gastric mucosal tonometry has been reported as a useful method to assess splanchnic perfusion during cardiovascular surgery, the conventional discontinuous method of tonometry (saline tonometry) was cumbersome and prone to systematic errors. A new automated system of air tonometry (Tonocap; Datex Ohmeda, Helsinki, Finland) allows for frequent (every 10 minutes) measurement of gastric regional CO2 (PrCO2) and may be more suitable as a monitoring system in cardiac patients. We evaluated the usefulness of continuous air tonometry as a marker of splanchnic perfusion during cardiopulmonary bypass (CPB). In 19 patients (53-79 years, mean 63 years) who underwent cardiovascular surgery under standard CPB with mild hypothermia (32 degrees C) from January 2001 to May 2002, the PrCO2 and calculated intramucosal pH (pHi) of gastric tonometry was monitored using Tonocap, and their relation to postoperative visceral organ function was evaluated. The pHi significantly increased after initiation of CPB from 7.32 +/- 0.07 to 7.43 +/- 0.10 (p < 0.05) and then consistently decreased in all patients to 7.39 +/- 0.09 at the end of CPB. The value of PrCO2 significantly (p < 0.01) correlated with the value of pHi. The lowest value of pHi during CPB was significantly related to blood urea nitrogen (r = -0.75, p < 0.05), serum creatinine (r = -0.78, p < 0.05), creatinine clearance (r = 0.68, p < 0.05) on postoperative day 1, and blood urea nitrogen (r = -0.84, p < 0.01) on day 3. In contrast, arterial blood lactate level, venous oxygen saturation, and routinely measured hemodynamics (e.g., pump flow, arterial pressure) during CPB were unrelated to the postoperative visceral organ function. These results suggest that continuous monitoring of gastric regional CO2 and pHi by air tonometry system is useful for the evaluation of splanchnic perfusion during CPB and may contribute to improve CPB technique by allowing the early detection of visceral malperfusion. 相似文献
47.
Koyama C Matsumoto H Sakai T Wakabayashi K Ito A Couch EF Inoue K 《Endocrine pathology》1995,6(1):67-75
A new cell line (TtT/GF) established from a murine pituitary thyrotropic tumor having characteristics similar to those of
pituitary folliculo-stellate cell (FS cell) was implanted into nude mice together with cells from a rat pituitary somatotrophic
tumor cell line (MtT/S) to determine whether the former enhances pituitary tumor growth. For as long as 2-3 mo after implantation,
MtT/S cells implanted either alone or together with fibroblasts formed either no tumors or only very small tumors in the nude
mice. In contrast all of the nude mice that had received MtT/S cells implanted together with TtT/GF cells developed large
tumors. Furthermore, the mice bearing the MtT/S and TtT/GF implants showed a significantly higher body weight and serum growth
hormone level than those bearing only MtT/S cells or a combination of MtT/S cells and fibroblasts. The TtT/GF cell line itself
had no tumorigenicity during the experimental period. Therefore, the TtT/GF cell line as a model of FS cells enhanced pituitary
endocrine cell tumor formation. Additionally, immunocytochemistry showed that TtT/GF cells positive for glial fibrillary acidic
protein (GFAP) or S-100 protein were present in the parenchymatous tissue elements or connective tissue surrounding the tumor
nests. In the parenchymatous tissue, the TtT/GF cells exhibited a stellate appearance and surrounded neighboring tumor cells
with their long cell processes. These results suggest that TtT/GF cells can serve as a model for pituitary FS cells, and are
capable of stimulating pituitary tumor growth either by modifying the microenvironment or producing growth factors. 相似文献
48.
Hepatitis C virus down-regulates insulin receptor substrates 1 and 2 through up-regulation of suppressor of cytokine signaling 3 总被引:15,自引:0,他引:15 下载免费PDF全文
Kawaguchi T Yoshida T Harada M Hisamoto T Nagao Y Ide T Taniguchi E Kumemura H Hanada S Maeyama M Baba S Koga H Kumashiro R Ueno T Ogata H Yoshimura A Sata M 《The American journal of pathology》2004,165(5):1499-1508
The pathogenesis of hepatitis C virus (HCV)-associated insulin resistance remains unclear. Therefore, we investigated mechanisms for HCV-associated insulin resistance. Homeostasis model assessment for insulin resistance was increased in patients with HCV infection. An increase in fasting insulin levels was associated with the presence of serum HCV core, the severity of hepatic fibrosis and a decrease in expression of insulin receptor substrate (IRS) 1 and IRS2, central molecules of the insulin-signaling cascade, in patients with HCV infection. Down-regulation of IRS1 and IRS2 was also seen in HCV core-transgenic mice livers and HCV core-transfected human hepatoma cells. Carbobenzoxy-l-leucyl-l-leucyl-l-leucinal, a potent proteosomal proteolysis inhibitor, blocked down-regulation of IRS1 and IRS2 in HCV core-transfected hepatoma cells. In human hepatoma cells, HCV core up-regulated suppressor of cytokine signaling (SOCS) 3 and caused ubiquitination of IRS1 and IRS2. HCV core-induced down-regulation of IRS1 and IRS2 was not seen in SOCS3(-/-) mouse embryonic fibroblast cells. Furthermore, HCV core suppressed insulin-induced phosphorylation of p85 subunit of phosphatidylinositol 3-kinase and Akt, activation of 6-phosphofructo-2-kinase, and glucose uptake. In conclusion, HCV infection changes a subset of hepatic molecules regulating glucose metabolism. A possible mechanism is that HCV core-induced SOCS3 promotes proteosomal degradation of IRS1 and IRS2 through ubiquitination. 相似文献
49.
Constitutive Expression of a Bacterial Pattern Recognition Receptor, CD14, in Human Salivary Glands and Secretion as a Soluble Form in Saliva 下载免费PDF全文
Akiko Uehara Shunji Sugawara Kouichi Watanabe Seishi Echigo Mitsunobu Sato Takahiro Yamaguchi Haruhiko Takada 《Clinical and Vaccine Immunology : CVI》2003,10(2):286-292
Saliva contains a number of proteins and glycoproteins that protect oral tissues, but little is known about the role of human saliva in innate immunity. Here we showed that human major salivary gland cells constitutively expressed a bacterial pattern recognition receptor, CD14, by immunohistochemistry. Human salivary gland cells in culture express CD14 mRNA and a 55-kDa CD14 protein in, but not on the cells, and secrete a soluble form with the same molecular mass. Human whole saliva contains a 55-kDa CD14, and the concentration of parotid saliva was 10-fold higher than whole saliva, which is comparable to that of serum CD14. Levels of CD14 in unstimulated whole and parotid saliva were unchanged before and after a meal and between unstimulated and stimulated saliva, indicating that saliva CD14 is constitutively secreted into the oral cavity. In contrast, lipopolysaccharide (LPS)-binding protein was below the detectable level. The saliva CD14 is functionally active in that it mediated the activation of CD14-lacking intestinal epithelial cells by LPS in a Toll-like receptor 4-dependent manner. These results suggested that saliva CD14 is important for the maintenance of oral health and possibly intestinal homeostasis. 相似文献
50.
Role of interleukin-18 (IL-18) in mycobacterial infection in IL-18-gene-disrupted mice 总被引:13,自引:0,他引:13 下载免费PDF全文
Immunity to mycobacterial infection is closely linked to the emergence of T cells that secrete cytokines, gamma interferon (IFN-gamma), interleukin-12 (IL-12), and tumor necrosis factor alpha (TNF-alpha), resulting in macrophage activation and recruitment of circulating monocytes to initiate chronic granuloma formation. The cytokine that mediates macrophage activation is IFN-gamma, and, like IL-12, IL-18 was shown to activate Th1 cells and induce IFN-gamma production by these cells. In order to investigate the role of IL-18 in mycobacterial infection, IL-18-deficient mice were infected with Mycobacterium tuberculosis and Mycobacterium bovis BCG Pasteur, and their capacities to control bacterial growth, granuloma formation, cytokine secretion, and NO production were examined. These mice developed marked granulomatous, but not necrotic, lesions in their lungs and spleens. Compared with the levels in wild-type mice, the splenic IFN-gamma levels were low but the IL-12 levels were normal in IL-18-deficient mice. The reduced IFN-gamma production was not secondary to reduced induction of IL-12 production. The levels of NO production by peritoneal macrophages of IL-18-deficient and wild-type mice did not differ significantly. Granulomatous lesion development by IL-18-deficient mice was inhibited significantly by treatment with exogenous recombinant IL-18. Therefore, IL-18 is important for the generation of protective immunity to mycobacteria, and its main function is the induction of IFN-gamma expression. 相似文献