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81.
Tokita H Murai S Kamitsukasa H Yagura M Harada H Takahashi M Okamoto H 《Journal of medical virology》2002,67(4):501-509
The TT virus (TTV) load was estimated in sera obtained from 237 patients with hepatitis C virus (HCV)-related chronic liver disease including 42 patients with hepatocellular carcinoma (HCC), by real-time detection PCR using primers and a probe derived from the well-conserved untranslated region of the TTV genome, which can detect all known TTV genotypes. Of the 237 patients studied, 18 (8%) were negative for TTV DNA, 87 (37%) had low TTV viremia (1.3 x 10(2)-9.9 x 10(3) copies/ml), and 132 (56%) had high TTV viremia (1.0 x 10(4)-2.1 x 10(6) copies/ml). Various features were compared between the patients with high TTV load (n = 132) and those with no TTV viremia or low viral load (n = 105). High TTV viremia (> or =10(4) copies/ml) was significantly associated with higher age (P < 0.05), past history of blood transfusion (P < 0.001), complication of cirrhosis (P < 0.05) or HCC (P < 0.0005), lower HCV RNA titer (P < 0.05), and lower platelet count (P < 0.01). On multivariate logistic regression analysis, high TTV viral load was a significant risk factor for HCC (P < 0.05), independent from known risk factors such as complication of liver cirrhosis (P < 0.0001) and high age (> or =65 years, P < 0.05), among all 237 patients. Furthermore, high TTV viral load was an independent risk factor for HCC among the 90 cirrhotic patients (P < 0.05). These results suggest that a high TTV viral load is associated independently with the complication of HCC and may have prognostic significance in patients with HCV-related chronic liver disease, although whether high TTV viremia mediates the progression of HCV-related chronic liver disease remains to be defined. 相似文献
82.
Takayasu H Motoi T Kanamori Y Kitano Y Nakanishi H Tange T Nakagawara A Hashizume K 《Human pathology》2002,33(8):852-855
The benign epithelial neoplasm liver cell adenoma is rare, especially in childhood. We report 2 such cases, 1 of which was associated with Prader-Willi syndrome. Differential diagnosis of the liver cell adenomas on the basis of histopathologic findings proved difficult and was based on the absence of cellular and nuclear atypia, mitotic activity, and invasive growth. In both cases, immunohistochemical staining demonstrated the nuclear accumulation of beta-catenin, and in 1 case, the tumor cells carried a mutation of the beta-catenin gene. Recently, disregulation of the Wnt/beta-catenin pathway, attributable to abnormalities of the beta-catenin gene, has been reported to be a major event in the development of hepatocellular carcinomas and hepatoblastomas. Our report may be the first to describe the beta-catenin abnormalities in childhood liver cell adenoma. These findings imply that abnormalities of beta-catenin can be an early initiating event in human liver tumorigenesis. 相似文献
83.
Uchibori E Kitano E Tsuji T Kitamura H 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(8):815-819
It is generally accepted that levels of serum whole complement activity (CH50) reflect the activities of complement (C) components of the classical C pathway (CP), since CH50 is assayed by use of sensitized sheep erythrocytes (EA). However, the alternative C pathway (AP) is considered to be also activated simultaneously in the process of activation of serum CP by EA. Thus, serum CH50 levels may possibly reflect not only CP but also AP activation in CH50 assay. We studied on the influence of AP activation during CH50 assay on CH50 levels, by comparison of CH50 levels in serum samples before and after treatment of factor D depletion. Polystyrene beads carrying polyanion, poly (2-acrylamide 2-methylpropane sulfonate) (PAMPS-beads), on the surface were prepared and used for preparation for factor D-depleted serum. After treatment of pooled normal human serum (NHS) with PAMPS-beads (2.5 mg/ml of serum), serum ACH50 level decreased to be undetectable, indicating that AP activation is prohibited in PAMPS-beads-treated serum. When isolated factor D was added to this PAMPS-beads-treated serum, ACH50 level recovered to that of before treatment. Immunoblot analysis revealed that factor D band observed in NHS disappeared completely after PAMPS-beads treatment. From these results, it is clear that factor-D deficient serum is prepared by PAMPS-beads treatment. Besides, since serum CH50 level was not decreased by PAMPS-beads treatment, it may be concluded that CH50 level is not affected by AP activation during CH50 assay. 相似文献
84.
Tomoko Matsumura Hiroto Narimatsu Masahiro Kami Koichiro Yuji Eiji Kusumi Akiko Hori Naoko Murashige Yuji Tanaka Kazuhiro Masuoka Atsushi Wake Shigesaburo Miyakoshi Yoshinobu Kanda Shuichi Taniguchi 《Biology of blood and marrow transplantation》2007,13(5):577-583
Cytomegalovirus (CMV) infection is a major complication after allogeneic hematopoietic stem cell transplantation (Allo-HSCT); however, we have little information on the clinical features of CMV reactivation after cord blood transplantation using reduced-intensity regimens (RI-CBT) for adults. We reviewed medical records of 140 patients who underwent RI-CBT at Toranomon Hospital between January 2002 and March 2005. All the patients were monitored for CMV-antigenemia weekly, and, if turned positive, received preemptive foscarnet or ganciclovir. Seventy-seven patients developed positive antigenemia at a median onset of day 35 (range, 4-92) after transplant. Median of the maximal number of CMV pp65-positive cells per 50,000 cells was 22 (range, 1-1806). CMV disease developed in 22 patients on a median of day 35 (range, 15-106); 21 had enterocolitis and 1 had adrenalitis. CMV antigenemia had not been detected in 2 patients, when CMV disease was diagnosed. CMV disease was successfully treated using ganciclovir or foscarnet in 14 patients. The other 8 patients died without improvement of CMV disease. In multivariate analysis, grade II-IV acute graft-versus-host disease was a risk factor of CMV disease (relative risk 3.48, 95% confidential interval 1.47-8.23). CMV reactivation and disease develop early after RI-CBT. CMV enterocolitis may be a common complication after RI-CBT. 相似文献
85.
Murakami Y Iwata H Kitano E Kitamura H Ikada Y 《Journal of biomaterials science. Polymer edition》2005,16(3):381-395
Bioartificial pancreas, in which the islets of Langerhans are enclosed in artificial membrane to be protected from the host immune system, is expected to be a promising medical device to treat patients who suffer from insulin-dependent diabetes. Our strategy for preparation of a bioartificial pancreas involves utilizing a membrane including polymeric materials that can inhibit the complement reaction. In this study, we examined the effects of poly(styrene sulfonic acid) (PSSa) on the alternative pathway of the serum complement system to identify the mechanism(s) involved. PSSa was dissolved in pooled normal human serum (NHS), and the mixtures were incubated at 37 degrees C for 30 min. Complement activities in sera were determined by hemolytic assays. Amounts of complement activation products released were determined by ELISA. Interactions of PSSa with complement components and fragments were examined with electrophoresis and immunoblotting. From these examinations, it appeared that the manner of PSSa effects on the alternative pathway (AP) highly depends on its concentration. PSSa seemingly acted as an activator when its concentration was 0.005 g/dl to 0.05 g/dl, while it acted as an inhibitor when its concentration was more than 0.1 g/dl. In terms of activation or inhibition of the AP, forming complex of PSSa with factor H induced activation, and that with factor D induced inhibition. 相似文献
86.
87.
88.
Yoshimura R Matsuyama M Hase T Tsuchida K Kuratsukuri K Kawahito Y Sano H Segawa Y Nakatani T 《International journal of molecular medicine》2003,12(6):861-865
Peroxisome proliferator activator-receptor (PPAR)-gamma ligand induces growth arrest of cancer cells through apoptosis. In this study, we examined the effects of PPAR-gamma inhibitors on cell proliferation in renal cell carcinoma (RCC), bladder tumor (BT), and prostatic carcinoma (PC) cell lines. We investigated the inhibitory effect of PPAR-gamma ligands, troglitazone and 15-deoxy-Delta12,14-prostaglandin J2 (15dPGJ2) on RCC, BT and PC-derived cell lines using MTT assay and Hoechst staining. PPAR-gamma ligands (troglitazone and 15dPGJ2) induced the reduction of cell viability with the half-maximal concentration of growth inhibition of RCC, BT, and PC cell lines. Furthermore, counting cells at days 1, 2 and 3, clearly showed marked inhibition of cell proliferation using troglitazone and 15dPGJ2. All PPAR-gamma inhibitors stopped the growth of all RCC, BT and PC cells. Cells treated with PPAR-gamma inhibitors showed chromatin condensation, cellular shrinkage, small membrane-bound bodies (apoptotic bodies), and cytoplasmic condensation. These cellular changes were typically redundant characteristics of apoptosis. PPAR-gamma ligands may mediate potent antiproliferative effects against RCC, BT and PC cells through differentiation. Thus, PPAR-gamma may become a new target in treatment of urological tumors. 相似文献
89.
Hirata I Hioki Y Toda M Kitazawa T Murakami Y Kitano E Kitamura H Ikada Y Iwata H 《Journal of biomedical materials research. Part A》2003,66(3):669-676
Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials. 相似文献
90.
Relationship between lipoxygenase and human testicular cancer 总被引:7,自引:0,他引:7
Yoshimura R Matsuyama M Mitsuhashi M Takemoto Y Tsuchida K Kawahito Y Sano H Nakatani T 《International journal of molecular medicine》2004,13(3):389-393
The metabolism of arachidonic acid by either the cyclooxygenase (COX) or lipoxygenase (LOX) pathway generates eicosanoids, which have been implicated in the pathogenesis of a variety of human diseases, including cancer. They are now believed to play important roles in tumor promotion, progression, and metastasis, and the involvement of LOX expression and function in tumor growth and metastasis has been reported in human tumor cell lines. Expressions of 5-LOX and 12-LOX in human testicular cancer (TC), and normal testis (NT) tissues were examined, as well as effects of their inhibitors on cell proliferation in TC cell line. Expressions of 5-LOX and 12-LOX were detected by immunohistochemistry. Effects of LOX inhibitors on TC cell growth were examined by MTT assay. While 5-LOX and 12-LOX expressions were slightly detected in NT tissues, expressions of 5-LOX and 12-LOX were significant detected in TC tissues by immunohistochemistry. The LOX inhibitors inhibited the growth of TC cells. LOX is induced in TC, and results may suggest that LOXs are essential for cell growth of TC cells. 相似文献