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排序方式: 共有1638条查询结果,搜索用时 15 毫秒
61.
Nakano Y Morita S Kawamoto A Suda T Chida K Nakamura H 《The Journal of allergy and clinical immunology》2003,112(3):525-530
BACKGROUND: Complement component C3a, an anaphylatoxin, provokes acute inflammatory responses, including smooth muscle contraction, mucus hypersecretion, increase in vascular permeability, and recruitment of inflammatory cells. Thus C3a may be related to airway inflammation and bronchoconstriction in acute asthma exacerbation. OBJECTIVE: We sought to determine whether plasma C3a is elevated in patients presenting for emergency treatment of acute asthma exacerbations and to correlate C3a concentrations with response to therapy. METHODS: Plasma C3a and serum eosinophil cationic protein were measured in 52 patients with acute asthma with peak expiratory flow of < or =50% the predicted value. Control subjects were 42 patients with stable chronic asthma. Patients with severe acute asthma were classified into 2 groups (admitted and discharged), according to how effective inhaled bronchodilators and systemic corticosteroids were in the first 2 hours of treatment. RESULTS: Concentrations of C3a in plasma from subjects in the admitted group (median, 256 ng/mL; range, 94 to 454) were significantly higher than those in the discharged group (197 ng/mL; 72 to 300) or those in patients with stable chronic asthma (166 ng/mL; 89 to 254; P <.0001). Elevated plasma C3a concentrations in admitted asthmatic patients decreased significantly by 7 days after admission (P =.0005). No significant difference was evident in serum eosinophil cationic protein concentration between the admitted group (33.1 microg/L; 6.3 to 143) and the discharged group (32.7 microg/L; 14.6 to 160; P =.99). CONCLUSIONS: Concentrations of C3a, which can induce airway inflammation and bronchoconstriction, were associated with differences in response to emergency treatment of severe asthma exacerbation. 相似文献
62.
Matsushita M Tanaka A Kikuchi K Kitazawa E Kawaguchi N Kawashima Y Kato T Fujikawa H Quaranta S Rosina F Gershwind ME Miyakawa H 《Autoimmunity》2002,35(8):531-536
Several lines of data suggest that genetic factors play an important role in the onset and/or progression of primary biliary cirrhosis (PBC). Since PBC is an autoimmune disease, it is reasoned to assume that genes encoding cytokines may confer susceptibility to disease. Amongst these factors, interleukin-10 (IL-10) has received significant attention. The promoter region of IL-10 gene has three single nucleotide polymorphisms (SNPs) at positions -1082, -819 and -592. To elucidate the association of the three SNPs of IL-10 promoter region with susceptibility of PBC in two different genetic populations, 159 unrelated patients with PBC (94 Italian and 65 Japanese) and 143 local controls (72 Italian and 71 Japanese) were enrolled. SNPs were determined using allele-specific PCR/RFLP. In Italian PBC patients, the frequency of homozygosity for G/G at position -1082 was significantly higher than that of local controls (p < 0.041, OR = 2.44, 95% C.I.; 1.02-5.86). The frequencies of haplotype GCC in PBC patients, possibly linked to higher IL-10 production, were also significant higher than local controls (p < 0.033). However, in Japanese population, there were no significant differences in the three SNPs and haplotypes between PBC patients and controls. Excessive production of IL-10 may play an important role in some populations in modulating the onset of PBC. Further, immunogenetic studies of PBC should take into account ethnic and geographic variations; this makes such studies in heterogeneous population, like the USA, more difficult. 相似文献
63.
The detection of IRF-1 promoter polymorphisms and their possible contribution to T helper 1 response in chronic hepatitis C. 总被引:3,自引:0,他引:3
Hidetsugu Saito Shinichiro Tada Kanji Wakabayashi Nobuhiro Nakamoto Masahiko Takahashi Mitsuyasu Nakamura Hirotoshi Ebinuma Hiromasa Ishii 《Journal of interferon & cytokine research》2002,22(6):693-700
We described the interferon (IFN) regulatory factor-1 (IRF-1) promoter single nucleotide polymorphisms (SNPs), and the clinical and immunologic implications of these SNPs have been investigated. We successfully determined the mutation at -300 of the IRF-1 promoter by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and this mutation linked with other mutations in the promoter region. In our Japanese population, the frequency of the type -300*A/A was 11.9%, type A/G was 54.2%, and type G/G was 33.9%. We found no significant difference without IFN stimulation in the production levels of IFN-gamma and interleukin-10 (IL-10) from peripheral blood mononuclear cells (PBMC) between subjects with -300*A/A and those with other types. IFN-alpha stimulation, however, increased the levels of IFN-gamma significantly and decreased the IL-10 production level significantly only in the subject with -300*A/A type. Flow cytometric analysis showed that the Th1-type CD4(+) cell population was significantly increased by IFN-beta administration only in the patient with chronic hepatitis C with -300*A/A type. These results suggest that the IRF-1 promoter SNP types are positively involved in Th1-type response and, consequently, the -300*A/A type may be beneficial for viral elimination in chronic hepatitis C and IFN therapy. 相似文献
64.
Chondroinduction of mouse mesenchymal stem cells in three-dimensional highly porous matrix scaffolds 总被引:5,自引:0,他引:5
Porous polyvinyl formal (PVF) resin and poly(lactide-caprolactone) [P(LA/CL)] sponges were examined as three-dimensional matrices for chondroinduction of cultured bone marrow mesenchymal stem cells (MSCs). Approximately 5 x 10(5) mouse MSCs were seeded in porous PVF resin or P(LA/CL) sponges and were cultured for up to 1 month in serum-free high-glucose Dulbecco's modified Eagle's medium containing 10 ng/mL transforming growth factor-beta3 and 100 nM dexamethasone for chondroinduction. After the 1-month culture period, the PVF resin and P(LA/CL) sponges contained approximately twice the amount of glycosaminoglycans compared with the control pellet. Safranin-O staining of PVF and P(LA/CL) after 1 month of culture revealed a cartilage-like extracellular matrix containing glycosaminoglycans and collagen. When implanted into nude mice, PVF and P(LA/CL) seeded with MSCs were found to be both biocompatible and chondroinductive. These highly porous scaffolds can maintain a large number of cells in a three-dimensional structure. Both are potentially promising for the chondroinduction of bone marrow MSCs for research and clinical applications. 相似文献
65.
For the purpose of applying fetal liver cells (FLCs) as a cell source to tissue-engineered bioartificial livers, three-dimensional (3-D) cultures of FLCs using a porous polymer scaffold, as well as monolayer cultures as a control, were simultaneously performed. To achieve efficient growth and differentiation, the FLCs were cultured in the growth medium for the first 3 weeks and then cultured in the differentiation medium for 3 more weeks. In these cultures, stimulating factors (oncostatin M (OSM), epidermal growth factor (EGF), hepatocyte growth factor (HGF), or dimethyl sulfoxide (DMSO)) were added to the media, and their effects were examined. When the growth medium containing OSM and EGF was used, EGF stimulated the growth of FLCs synergistically with OSM. For the differentiation of FLCs into mature hepatocytes, DMSO added to the differentiation medium remarkably enhanced albumin secretion in the 3-D and monolayer cultures, although HGF was effective only in the monolayer culture. Microscopic observation proved that FLCs exhibited hepatocyte-like morphology only in the media containing DMSO. In conclusion, successive supply of the growth medium containing EGF and OSM and the differentiation medium containing DMSO efficiently induced the growth of the 3-D cultured FLCs and their differentiation into mature hepatocytes. 相似文献
66.
Takeshita M Nakamura S Kikuma K Nakayama Y Nimura S Yao T Urabe S Ogawara S Yonemasu H Matsushita Y Karube K Iwashita A 《Histopathology》2011,58(3):395-407
Takeshita M, Nakamura S, Kikuma K, Nakayama Y, Nimura S, Yao T, Urabe S, Ogawara S, Yonemasu H, Matsushita Y, Karube K & Iwashita A(2011) Histopathology 58 , 395–407 Pathological and immunohistological findings and genetic aberrations of intestinal enteropathy‐associated T cell lymphoma in Japan Aims: To elucidate the clinicopathological findings of primary intestinal enteropathy‐associated T cell lymphoma (EATL) in Japan, a non‐endemic area for coeliac disease. Methods and results: Of the 24 cases, four (17%) had large‐cell lymphoma (type I), and the remaining 20 (83%) had medium‐sized lymphoma (type II). Lymphoma cells of the three type I cases were CD56‐positive. Only one (4%) case showed typical CD56‐ and CD8‐negative and CD30‐positive type I EATL. In type II EATL, lymphoma cells of the 16 (80%) and 11 (55%) cases were positive for CD56 and CD8, respectively. Intramucosal tumour spreading and adjacent enteropathy‐like lesions were detected in 15 (71%) and 16 (76%) of 21 cases, with a severe increase of intraepithelial lymphocytes (IELs) in 12 (57%). IELs of enteropathy‐like lesions in five (24%) cases expressed T‐bet, with no cases of CD30‐positive IELs. Characteristic findings from comparative genomic hybridization of 15 cases indicated gains of 8q2 (47%), Xp (53%) and Xq (73%), but no gain of 9q3. Regarding, human leucocyte antigen (HLA) status, six cases examined did not express the DQB1*02 allele. Conclusions: Japanese EATL exhibited different histology, cytogenetic findings and HLA status from those of typical type I EATL. The rare incidence of coeliac disease may influence the tumour cell characteristics of EATL and IELs. 相似文献
67.
Yukari Okita Ling Zheng Kunio Kawanishi Hirotoshi Miyoshi Kazuyoshi Yanagihara Mitsuyasu Kato 《Genes to cells : devoted to molecular & cellular mechanisms》2021,26(5):336-343
Three-dimensional (3D) culturing mimics the heterogeneous cellular conditions of the in vivo tumor microenvironment compared to 2D monolayer-cultured cells and 3D cultures of established cancer cell lines (sphere culture) or patient-derived cancer cells (organoid culture) are frequently used for cancer research or drug screening and evaluation. To establish more cost and time-efficient 3D culture methods for cancer cell lines, we supplemented sphere culture medium with polyvinyl alcohol (PVA) and found that 3D sphere cultures of breast and pancreatic cancer cell lines were significantly increased. Mechanistically, we found that PVA prevented cell death and promoted cellular proliferation while maintaining levels of stemness-related gene expression. Furthermore, we showed that polyvinyl formal resin (PVF) 3D scaffolds made by cross-linked PVA can function in serum-free, long-term 3D cultures to support maintenance of sphere- or tumor-like cell masses for diverse cancer cell types. Taken together, we demonstrate the effectiveness of PVA and PVF in human cancer cell line culture protocols. 相似文献
68.
Fukuba Y Endo MY Ohe Y Hirotoshi Y Kitano A Shiragiku C Miura A Fukuda O Ueoka H Miyachi M 《European journal of applied physiology》2007,99(4):361-369
It has frequently been demonstrated that prior high-intensity exercise facilitates pulmonary oxygen uptake response at the onset of subsequent identical exercise. To clarify the roles of central O2 delivery and/or peripheral O2 extraction in determining this phenomenon, we investigated the relative contributions of cardiac output (CO) and arteriovenous
O2 content difference to the transient during repeated bouts of high-intensity knee extension (KE) exercise. Nine healthy subjects volunteered to participate
in this study. The protocol consisted of two consecutive 6-min KE exercise bouts in a supine position (work rate 70–75% of
peak power) separated by 6 min of rest. Throughout the protocol, continuous-wave Doppler ultrasound was used to measure beat-by-beat
CO (i.e., via simultaneous measurement of stroke volume and the diameter of the arterial aorta). The phase II response was significantly faster and the slow component (phase III) was significantly attenuated during the second KE bout
compared to the first. This was a result of increased CO during the first 30 s of exercise: CO contributing to 100 and 56%
of the speeding at 10 and 30 s, respectively. After this, the contribution of became increasingly more predominant: being responsible to an estimated 64% of the speeding at 90 s, which rose to 100% by 180 s. This suggests that, while both CO and clearly interact to determine the response, the speeding of kinetics by prior high-intensity KE exercise is predominantly attributable to increases in . 相似文献
69.
Combination tumor immunotherapy with radiotherapy and Th1 cell therapy against murine lung carcinoma
Yokouchi H Chamoto K Wakita D Yamazaki K Shirato H Takeshima T Dosaka-Akita H Nishimura M Yue Z Kitamura H Nishimura T 《Clinical & experimental metastasis》2007,24(7):533-540
Mice bearing established Lewis lung carcinoma (LLC) expressing model tumor antigen, ovalbumin (OVA) (LLC-OVA) marginally responded
to local radiotherapy, but none of the mice was cured. In contrast, treatment of the tumor-bearing mice with intratumoral
injection of tumor-specific T helper type 1 (Th1) cells and tumor antigen (OVA) after radiotherapy dramatically prolonged
the survival days and induced complete cure of the mice at high frequency (80%). Radiation therapy combined with Th1 cells
or OVA alone showed no significant therapeutic activity against LLC-OVA. Such a strong therapeutic activity was not induced
by intratumoral injection of Th1 cells plus OVA. Compared with other treatment, radiation therapy combined with Th1 cells
and OVA was superior to induce the generation of OVA/H-2b tetramer+ tumor-specific cytotoxic T lymphocyte (CTL) with a strong cytotoxicity against LLC-OVA in draining lymph node (DLN). Moreover,
the combined therapy is demonstrated to inhibit the growth of tumor mass, which grew at contralateral side. These results
indicated that radiotherapy combined with Th1 cell/vaccine therapy induced a systemic antitumor immunity. These findings suggested
that combination therapy with radiotherapy and Th1 cell/vaccine therapy may become a practical strategy for cancer treatment.
Hiroshi Yokouchi and Kenji Chamoto are equally contributed. 相似文献
70.
Ryo Nishio Toshiro ShinkeHiromasa Otake Masayuki NakagawaTakumi Inoue Hirotoshi HarikiTsuyoshi Osue Yu TaniguchiMasamichi Iwasaki Noritoshi HiranumaAkihide Konishi Hiroto KinutaniMasaru Kuroda Ken-ichi Hirata 《Thrombosis research》2013