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31.
Hiroto Egawa Shingi Uemoto Yasutugu Takada Kazue Ozawa Satoshi Teramukai Hironori Haga Mureo Kasahara Kouhei Ogawa Hiroshi Sato Masako Ono Kenji Takai Masanori Fukushima Kayo Inaba Koichi Tanaka 《Liver transplantation》2007,13(9):1262-1271
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance. 相似文献
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Differentiation of blast cells from a Down's syndrome patient with transient myeloproliferative disorder 总被引:2,自引:0,他引:2
Suda J; Eguchi M; Akiyama Y; Iwama Y; Furukawa T; Sato Y; Miura Y; Suda T; Saito M 《Blood》1987,69(2):508-512
A male neonate with Down's syndrome and congenital myeloproliferative disorder was studied. His blood picture showed the unique coexistence of leukocytosis with matured cells and a large number of blast cells. The in vitro proliferation and differentiation of blast cells into various lineages in the presence of phytohemagglutinin-stimulated leukocyte conditioned medium (PHA-LCM) was examined by using a liquid culture and a methylcellulose culture system. The differentiation of blast cells into myeloid cells was confirmed by specific cytochemical stainings, electron microscopy, and an immunologic study. No specific factors in the plasma of the patient promoted the proliferation or differentiation of blast cells. The cellular composition of colonies grown in methylcellulose culture from single blast cells was studied by a micromanipulation technique. High plating efficiency was observed. Of 136 cultures, 78 showed colony growth. Half of the blast cells were colony-forming cells that could proliferate and differentiate into basophils, neutrophils, eosinophils, macrophages, and erythrocytes in the presence of PHA-LCM. Using the blast cells with a high differentiation capacity to the basophil pathway, we studied the effect of recombinant granulocyte-macrophage colony-stimulating factor (GM- CSF). Recombinant GM-CSF support neutrophils, eosinophils, and macrophages but not typical basophils. These findings of the cell differentiation of blast cells into various kinds of cells in vitro were in agreement with the finding of neutrophilia, eosinophilia, basophilia, and thrombocythemia in this patient. 相似文献
35.
N Sato 《Nihon Geka Gakkai zasshi》1986,87(12):1511-1525
The relationship between nutritional status and muscle strength was examined in 73 patients with gastrointestinal carcinoma preoperatively. Nutritional status was assessed by measuring various nutritional parameters. Muscle strength was determined by measurements of %grip strength and respiratory muscle strength expressed as %maximal expiratory and inspiratory pressure (%MEP and %MIP). The results were as follows: %GS was significantly low in the patients who showed low values in body weight (%ideal body weight: %IBW), mid-arm muscle circumference (%AMC), serum albumin (Alb), serum prealbumin (PA), total peripheral lymphocyte count (TLC), and/or nutritional surgical risk index (NRI). %MEP was significantly low in the patients who showed low values in %IBW, %AMC, triceps skin fold, Alb, PA, retinol binding protein, NRI, and/or nutritional assessment index (NAI). %MIP was significantly low in the patients who showed low values in %IBW, %AMC, creatinine height index, Alb, PA, NRI, and/or NAI. %MEP and %MIP were significantly correlated with %GS. Preoperative %GS value was significantly low in the esophageal cancer patients with postoperative pulmonary complications. It was suggested that %GS was a simple and useful nutritional parameter for detecting depletion of the muscle mass and visceral proteins, for respiratory muscle strength, and for functional capacity of muscle. 相似文献
36.
Augmentation and subsequent attenuation of Ca2+ current due to lipid peroxidation of the membrane caused by t-butyl hydroperoxide in the rabbit sinoatrial node. 总被引:2,自引:1,他引:1
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N. Sato M. Nishimura H. Tanaka N. Homma Y. Watanabe 《British journal of pharmacology》1989,98(3):721-723
Cellular electrophysiological effects of membrane lipid peroxidation by t-butyl hydroperoxide (TBH) were studied in the rabbit sinoatrial (SA) node. Superfusion for 1-5 min with 300 microM TBH caused an initial increase and subsequent decrease in the spontaneous firing frequency of the SA node. Voltage clamp experiments revealed that TBH initially enhanced but later blocked the Ca2+ current. Thus, membrane lipid peroxidation appears to accelerate and then suppress physiological automaticity by causing biphasic changes in the Ca2+ current. 相似文献
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38.
A 68-year-old man had subacute cerebellar degeneration and a non-Hodgkin's lymphoma. Using an immunoblotting method, we found serum antibodies to rat cerebral 250-kd and 110-kd and cerebellar 110-kd acidic cytoplasmic proteins. The antibodies did not react unless the antigens were prepared soon after death with protease inhibitors. Two hundred fifty-kd and 110-kd proteins are minor components of soluble cytoplasmic proteins of the brain. The molecular weights differed from other soluble brain-specific proteins already characterized. 相似文献
39.
We tried to detect HTLV-I-related sequences in Japanese patients with multiple sclerosis with a highly sensitive method that employs the polymerase chain reaction (PCR) of genomic DNA followed by Southern blot hybridization analysis. To amplify HTLV-I sequences, we used primers for LTR, pol, gag, and env coding regions. Fourteen patients with definite MS, 14 disease controls, 12 normal controls, and 3 patients with HTLV-I-associated myelopathy (HAM) were investigated. Results of particle aggregation assay for HTLV-I antibodies were negative in serum from all subjects except for the 3 HAM patients. Neither the 14 MS patients nor the 26 controls showed the presence of any highly homologous sequences to HTLV-I. We did observe faint signals for gag, pol, and env coding regions only at low stringent hybridization in some MS patients as well as some normal controls. The nucleotide sequence analysis of the faint bands was more homologous to major histocompatibility complex molecules than the HTLV-I genome. 相似文献
40.
T Sato Y Kawakami Y Nagai T Kawai T Kozaki Y Nezu T Kobayashi 《Journal of nutritional science and vitaminology》1990,36(4):299-309
The thermal conversion of 1 alpha-hydroxyprevitamin D3 (1 alpha-OH-previtamin D3) diacetate to 1 alpha-hydroxyvitamin D3 (1 alpha-OH-vitamin D3) diacetate was investigated in five solvents. The fraction of 1 alpha-OH-vitamin D3 diacetate was calculated from the HPLC peak areas (UV detection) of 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. When 1 alpha-OH-previtamin D3 diacetate was dissolved in ethanol, benzene, toluene, isopropyl ether, or n-hexane, and heated at 60 degrees C, the yield of 1 alpha-OH-vitamin D3 diacetate increased during the first 4 h, and reached an equilibrium level after 8.5 h. Differences in the ratio of 1 alpha-OH-previtamin D3 diacetate to 1 alpha-OH-vitamin D3 diacetate at thermal equilibrium, and in the rate of the thermal isomerization were observed among these five solvents. Molecular mechanics (MM) calculations were performed in order to estimate solvent effects on conformation for 1 alpha-OH-previtamin D3 diacetate and 1 alpha-OH-vitamin D3 diacetate. The solvent effect was treated by specifying a dielectric constant representative of each of the three solvents: ethanol (polar), n-hexane (nonpolar), and benzene (aromatic). The dielectric constants used were 24.3 for ethanol, 1.5 for n-hexane, and 2.3 for benzene. It is suggested that the conformation of 1 alpha-OH-vitamin D3 diacetate is stabilized in polar solvent. However, the order of conformational stability when solvent effects are included in the calculations is: ethanol greater than benzene greater than n-hexane. This order does not follow the experimental results. The proton NMR chemical shifts of 1 alpha-OH-vitamin D3 diacetate are different in deuterated n-hexane, ethanol, and benzene. The downfield shift of the C-6 vinyl proton of 1 alpha-OH-vitamin D3 diacetate, when compared to the chemical shift in benzene, is 0.15 and 0.11 ppm relative to the chemical shift in n-hexane and ethanol, respectively, and that of the C-7 proton was 0.30 and 0.33 ppm, respectively. No significant proton shift of 1 alpha-OH-previtamin D3 diacetate is recorded in these three solvents. To account for the increased ratio of 1 alpha-OH-vitamin D3 diacetate to 1 alpha-OH-previtamin D3 diacetate ratio in benzene, we suggest that 1 alpha-OH-vitamin D3 diacetate may be stabilized via specific solute-solvent interactions in benzene. 相似文献