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991.
Kikuchi Y Koarada S Nakamura S Yonemitsu N Tada Y Haruta Y Morito F Ohta A Miyake K Horiuchi T Nagasawa K 《Clinical and experimental rheumatology》2008,26(1):5-12
OBJECTIVE: To quantify the activated B cells in the peripheral blood and salivary glands of patients with Sj?gren's syndrome (SS) by analyzing the expression of RP105 molecule on the B cells. METHODS: The expression of RP105 on the peripheral blood B cells of patients with SS (19 cases) was analyzed by flow cytometry. RP105-positive and negative B cells were sorted and cultured in vitro and the amount of immunoglobulins (IgG and IgM) produced in the supernatant was measured by enzyme-linked immunosorbent assay (ELISA). Salivary gland biopsy samples from 9 SS patients were histologically evaluated and the sequential frozen sections were separately immunostained by anti-RP105 and anti-CD20 monoclonal antibodies. RESULTS: A significantly higher proportion of peripheral blood RP105-negative B cells was found in SS patients than in healthy individuals. RP105-negative, but not positive, B cells from SS patients were capable of producing IgG and IgM spontaneously in vitro, which was enhanced by the addition of Staphylococcus aureus Cowan I strain (SAC) or IL-6. Salivary glands from 2 of 9 SS patients were found to have lymphoid follicles whose germinal centers consisted of RP105-negative B cells. Moreover, a larger proportion of B cells extensively infiltrating the area other than lymphoid follicles was also RP105-negative. CONCLUSION: RP105-negative B cells, a subset of highly activated and well differentiated B cells, which are increased in number in the peripheral blood and extensively infiltrate salivary glands, may be responsible for the production of class-switched immunoglobulin in SS. In addition, those cells might be associated with the inflammation and tissue damage of the salivary glands. 相似文献
992.
C Morita T Horiuchi H Tsukamoto N Hatta Y Kikuchi Y Arinobu T Otsuka T Sawabe S Harashima K Nagasawa Y Niho 《Arthritis and rheumatism》2001,44(12):2819-2827
OBJECTIVE: To investigate whether a polymorphism(s) or mutation(s) in the tumor necrosis factor receptor II (TNFRII) gene is involved in the pathogenesis of systemic lupus erythematosus (SLE). METHODS: All 10 exons of the TNFRII gene were analyzed by exon-specific polymerase chain reaction-single-strand conformation polymorphism, followed by nucleotide sequencing of exons that displayed aberrant bands. To analyze the function of the TNFRII polymorphisms, the full-length TNFRII complementary DNA of each allele was transfected in HeLa cells and then studied for specific binding of 125I-TNFalpha, as well as interleukin-6 (IL-6) production and cytotoxic activity after treatment with recombinant human TNFalpha. RESULTS: We identified 4 polymorphisms, at codons 56, 181, 196, and 232. The latter 2 had amino acid substitutions M196R and E232K, respectively. Only the 196R allele was significantly associated with SLE in our 105 Japanese SLE patients, with an allele frequency of 20.5%, compared with 12.6% in 99 healthy controls (P = 0.0335). More importantly, using TNFRII-transfected HeLa cells, we demonstrated significantly increased IL-6 production by 196R TNFRII compared with 196M TNFRII. The cytotoxic activity induced by 196R TNFRII was also increased compared with that of 196M TNFRII. This increase was achieved without affecting the binding affinity of TNFalpha to TNF-RII, as demonstrated by the finding that specific TNFalpha binding to the HeLa transfectants of 196R and 196M TNFRII was similar, with Kd values of 3.12 x 10(-10)M and 4.34 x 10(-10)M, respectively. CONCLUSION: These results suggest that 196R TNFRII, which transduces the signals of TNFalpha more effectively than does 196M TNFRII, is involved in the pathogenesis of SLE. 相似文献
993.
Takayuki Nakagomi Osamu Kitada Hitoshi Nakamura Shigeru Miyata Kazumi Aragane Taku Kodama Kouzou Kuribayashi Shoko Jin Noriko Takenaka Namiko Nagasawa Minoru Sugita 《Nihon Kokyūki Gakkai zasshi》2002,40(10):812-816
A 60-year-old man was admitted to our hospital complaining of progressive dyspnea. On admission, he had marked hypoxemia, and his chest radiography and computed tomography (CT) showed ground glass opacities and multiple emphysematous changes in both lung fields. On examining the patient's bronchoalveolar lavage fluid (BALF). Pneumocystis carinii pneumonia (PCP) was diagnosed. A serological test for human immunodeficiency virus (HIV)-1, 2 was positive, and acquired immunodeficiency syndrome (AIDS) was diagnosed. Since the chest CT performed a month before the patient's admission to our hospital revealed ground glass opacities in both lung fields we thought that he had already developed PCP at that time. In comparison with his previous CT, the chest CT on admission showed progressive ground glass opacities and emphysematous changes. Although PCP is known to display various findings on chest radiography and CT, emphysematous changes are rarely reported in Japan. In this case we were able to confirm these changes and observe its progression using chest CT. 相似文献
994.
Neuregulin-1 protects ventricular myocytes from anthracycline-induced apoptosis via erbB4-dependent activation of PI3-kinase/Akt 总被引:2,自引:0,他引:2
Fukazawa R Miller TA Kuramochi Y Frantz S Kim YD Marchionni MA Kelly RA Sawyer DB 《Journal of molecular and cellular cardiology》2003,35(12):1473-1479
We have found that neuregulin-1beta (NRG-1beta) is expressed in the cardiac microvascular endothelium, and promotes the growth and survival of cardiac myocytes in culture through the activation of erbB2 and erbB4 receptor tyrosine kinases. In this study, we examined the role of NRG-1/erbB signaling in protection of cardiac myocytes from anthracycline-induced apoptosis in vitro to determine the coupling between erbB receptor subtypes and cytoprotective signaling. Treatment of neonatal rat ventricular myocytes with NRG-1beta inhibited daunorubicin-induced apoptosis as shown by terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling staining for DNA fragmentation as well as flow cytometric quantification of apoptotic myocytes. Daunorubicin-induced activation of caspase-3 in cardiomyocytes was similarly inhibited by NRG-1beta. The phosphoinositol-3-kinase (PI3-kinase) inhibitor wortmannin prevented the effects of NRG-1beta on daunorubicin-induced apoptosis and activation of caspase-3. NRG-1beta treatment induced rapid activation of Akt/PKB that was inhibited by wortmannin, and adenoviral-mediated overexpression of a dominant-negative Akt prevented the protective effect of NRG-1beta. Akt activation by NRG-1beta was prevented by the tyrphostin AG1478, which we show inhibits erbB4 activation by NRG-1beta. In contrast, the erbB2-specific tyrphostin AG879 had no effect on NRG-1beta activation of Akt. Myocyte treatment with an activating antibody to erbB2 caused phosphorylation of erbB2, and led to activation of Erk but not Akt. Treatment with the erbB2 antibody had no effect on anthracycline-induced apoptosis. Thus, NRG-1beta protects against anthracycline-induced apoptosis via erbB4-dependent activation of the PI3-kinase/Akt pathway. 相似文献
995.
Minemura K Takeda T Minemura K Nagasawa T Zhang R Leopardi R DeGroot LJ 《Endocrinology》2000,141(5):1814-1822
Herpes simplex virus thymidine kinase (HSVtk) gene transfer followed by ganciclovir administration is a common strategy for experimental cancer therapy. To evaluate the feasibility of using the human calcitonin promoter to target medullary thyroid carcinoma (MTC), we developed adenovirus vectors containing Escherichia coli beta-galactosidase gene under the control of the CALC-I promoter (AdCTlacZ), or the human cytomegalovirus promoter (AdCMVlacZ). Beta-galactosidase activity driven by the CALC-I promoter was higher than by the CMV promoter in rat MTC cells after infection with adenovirus vectors. AdCTlacZ induced an equal or lower expression level of beta-galactosidase in TT (human MTC), T98G, Cos1, HepG2, and HeLa cells compared with AdCMVlacZ. To inhibit the growth of MTC cells, we developed two adenovirus vectors, AdCMVtk carrying HSVtk driven by the cytomegalovirus promoter and AdDCTtk containing a human CALC-I minigene under the control of the CALC-I promoter. HSVtk is fused to a portion of calcitonin coded in exon 4 to direct cell-specific regulation of splicing. All cell lines infected with AdCMVtk were rendered sensitive to ganciclovir, whereas T98G and Cos1 cells infected with AdDCTtk were not affected. Cell killing was also observed in HeLa, HepG2, rat MTC and TT cells infected with AdDCTtk. 相似文献
996.
Shigeaki Suenaga Kunihiro Nagayama Taisuke Nagasawa Yoshihiro Kawabata Hiroko Indo Hideyuki J. Majima 《Oral Radiology》2016,32(2):87-97
Objectives
To evaluate the correlations between temporomandibular joint (TMJ) pain and both conventional and gadolinium-enhanced magnetic resonance (MR) imaging characteristics in patients with temporomandibular disorders (TMDs).Methods
T1-weighted, T2-weighted, and fat-suppressed contrast-enhanced T1-weighted MR imaging were performed in 80 TMD patients with the main complaint of TMJ pain. A kappa statistical analysis was performed to calculate the interobserver agreement between two of three radiologists. The relationships between TMJ pain and various MR findings were analyzed by multiple comparison test, Spearman’s rank correlation test, Chi-square test, Student’s t test, and multivariate logistic regression analysis.Results
Significant correlations were observed between anterior disk displacement without reduction, joint effusion, and TMJ pain (p < 0.01). The degree of contrast enhancement of the posterior disk attachment was correlated with the severity of TMJ pain, especially spontaneous pain (r = 0.725, p < 0.01), while no correlation was observed in the masticatory muscle pain group. The correlation tended to be higher in the latero-central portions than in the medial portion of the mandibular condyle, although no significant difference was seen.Conclusions
It has been suggested that fat-suppressed contrast-enhanced MR imaging techniques facilitate better understanding of the sources of TMJ pain, but not masticatory muscle pain, and could reflect TMJ synovial inflammation. The severity of TMJ pain was closely correlated with the degree of contrast enhancement. The above-mentioned correlation had a tendency to be higher in the latero-central portions of the mandibular condyle.997.
Akihiro Ohmoto Michifumi Kohno Masahiro Ieko Ryuji Matsuyama 《Modern rheumatology / the Japan Rheumatism Association》1997,7(4):271-278
Our objective was to appraise bronchial hyperresponsiveness in Sjögren’s syndrome (SS) and to analyze the clinical aspects of those patients. Forty-five patients with primary and secondary SS underwent examination with chest X-ray, spirometry and directly writing of the dose-response curve of respiratory resistance (Rrs) during the continuous inhalation of methacholine in stepwise incremental concentrations (astograph). Thirty-one patients (68.9%) had bronchial hyperresponsiveness. Ten out of 12 (83.3%) patients with extraglandular involvement had bronchial hyperresponsiveness. The threshold of the increase of Rrs in SS patients was significantly higher than bronchial asthma. This paper shows that some patients with SS have bronchial hyperresponsiveness; especially in patients with extraglandular involvement, it occurs at a high incidence. In addition, the pattern of the dose-response curve with bronchial hyperresponsiveness in SS was similar to that of chronic bronchitis rather than bronchial asthma in the methacholine inhalation test. 相似文献
998.
Tomizawa D Aoki Y Nagasawa M Morio T Kajiwara M Sekine T Shimizu N Kato M Yachie A Mizutani S 《European journal of haematology》2005,75(5):441-444
Omenn syndrome is a variant form of severe combined immunodeficiency. It is fatal unless treated by allogeneic stem cell transplantation (SCT), which is the only curative approach. However, both treatment-related complications and graft rejection are major obstacles to treatment success. This report describes a case with Omenn syndrome who developed mixed chimerism after unrelated cord blood transplantation (UCBT). This case was successfully treated by altering the patient's immunosuppression and donor lymphocyte infusion (DLI) with donor cord blood-derived activated CD4+ T cells ex vivo expanded from the cord blood cell residues in an infused bag. This novel development to expand CD4+ T-lymphocytes from the donor cord blood unit for the use of DLI would serve as a useful method to overcome the risk of graft rejection in SCT for primary immunodeficiency disorders with residual cell-mediated immunity without compounding graft-vs.-host disease, especially in the UCBT setting. 相似文献
999.
Watanabe T Suzuya H Onishi T Kanai S Kaneko M Watanabe H Nakagawa R Kawano Y Takaue Y Kuroda Y Talmadge JE 《International journal of hematology》2003,77(1):75-81
Granulocyte colony-stimulating factor (G-CSF) has been shown to affect the biochemical markers of bone metabolism, including serum bone alkaline phosphatase (BALP), serum osteocalcin, and urine deoxypyridinoline. To determine the association between bone resorption and formation and the G-CSF-induced mobilization of peripheral blood stem cells (PBSC), we examined these markers during mobilization in 19 healthy donors. The average (+/- SEM) serum BALP level before treatment was 81.6 +/- 17.0 IU/dL, and the level increased significantly to 117.7 +/- 15.8 IU/dL on day 5 of G-CSF administration (P < .0001). The urine deoxypyridinoline level before treatment was 12.3 +/- 2.4 nmol/mmol creatinine, and this level also increased significantly to 19.4 +/- 3.0 nmol/mmol creatinine on day 5 of G-CSF administration (P < .0001). In contrast, the average level of serum osteocalcin significantly decreased from 8.07 +/- 2.88 ng/mL to 1.53 +/- 0.18 ng/mL on day 5 (P = .0353). During G-CSF administration, we also studied the serum levels of various cytokines (IL-1beta, osteoclastogenesis inhibitory factor [OCIF], IL-6, tumor necrosis factor alpha, transforming growth factor beta, interferon-gamma, macrophage colony-stimulating factor) related to bone metabolism. Only the kinetics of OCIF were significantly affected. The serum level of OCIF increased immediately after the start of G-CSF administration and remained high during G-CSF administration. These results demonstrate that high-dose G-CSF affects bone metabolism and that OCIF may play a role in bone metabolism. Consistent with the notion that G-CSF affects bone metabolism, a significant correlation was observed between CD34+ cell yield and the increase in urine deoxypyridinoline but not for the changes in serum BALP and osteocalcin levels. This result suggests that bone resorption is either directly or indirectly related to the mobilization of PBSC by G-CSF. 相似文献
1000.
Tomizawa D Imai K Ito S Kajiwara M Minegishi Y Nagasawa M Morio T Nonoyama S Mizutani S 《American journal of hematology》2004,76(1):33-39
X-linked hyper-IgM syndrome (XHIM), or hyper-IgM syndrome type 1 (HIGM1), is a rare primary immunodeficiency disorder susceptible to recurrent bacterial infection and opportunistic infection such as Pneumocystis carinii and Cryptosporidium parvum. The long-term outcome is quite poor, and allogeneic hematopoietic stem cell transplantation (HSCT) offers the only cure. Seven patients with XHIM, from age 3 to 19 years (mean 11.3 years), underwent allogeneic HSCT in our institution. Details of pre- and post-transplantation data and transplantation procedure were analyzed retrospectively. The donors were HLA-identical siblings for three patients and HLA-identical unrelated donors for four patients. All but one received conventional conditioning regimen consisting of busulfan and cyclophosphamide and prophylaxis for graft-versus-host disease (GVHD) consisting of cyclosporine and methotrexate. Five out of seven patients are alive and well with normal CD40L expression, and four of these five are free of intravenous immunoglobulin supplementation. The two patients who died had prolonged episodes of severe and recurrent infections and organ damage. We conclude that conventional allogeneic HSCT from HLA matched related or unrelated donors is curative and feasible for XHIM patients, if performed before significant infections and organ damage occur. For the high-risk patients, an alternative approach including nonmyeloablative HSCT may be more feasible. 相似文献