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171.
1,25-Dihydroxyvitamin-D3 (1,25-D3) is known to inhibit DNA synthesis, immunoglobulin and lymphokine production [interleukin-2 (IL-2), gamma interferon (G-IFN), and granulocyte-monocyte colony-stimulating factor (GM-CSF)] by mitogen-stimulated human peripheral blood mononuclear cells (PBMCs). Recent data suggest these inhibitory effects are mediated at the gene level through inhibition of mRNA accumulation of specific lymphokines in the activated cells. In previous studies, we have demonstrated the CD8+ T cell population was less sensitive to the anti-proliferative actions of 1,25-D3 than CD4+ T cells. The purpose of this investigation was to further assess ability of 1,25-D3 to regulate CD4+ and CD8+ T cell functions. Initial experiments showed that 1,25-D3 inhibited both IL-2 production and mRNA accumulation in mitogen-stimulated PBMC. However, IL-2 receptor (IL-2R) expression and mRNA accumulation in stimulated PBMC was not affected by 1,25-D3. Both FACS sorted CD4+ and CD8+ T cells expressed IL-2R equally upon stimulation and neither showed an inhibitory effect on this expression by 1,25-D3. Human CD4+ and CD8+ T cells showed a stimulus-specific production of IL-2. CD4+ cells stimulated with mitogen and HLA-DR positive accessory cells produced measurable levels of IL-2 that were completely inhibited by 1,25-D3. CD8+ T cells did not generate measurable amounts of IL-2 in this system. However, CD4+ and CD8+ T cells produced large amounts of IL-2 when stimulated with mitogen and a protein kinase C activator, phorbol myristate acetate (PMA). Under these circumstances, both CD4+ and CD8+ T cell IL-2 production was inhibited completely by 1,25-D3. These data suggest that IL-2R expression in PBMCs and T cell subsets is equal and unaffected by 1,25-D3 while IL-2 production in T cell subsets is stimulus-specific and completely inhibited by 1,25-D3. 相似文献
172.
A Sakai K Sasaki H Mizusawa M Ishidate 《Teratogenesis, carcinogenesis, and mutagenesis》1990,10(4):333-340
Quercetin was examined for the effects on the two-stage chemical transformation of BALB/3T3 cells. Quercetin showed initiating action to induce transformation in the cells which were treated with quercetin and subsequently with 0.49 microM 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Both the proportion of dishes with transformed foci and the average number of foci per dish increased with the concentration of quercetin (15-45 microM). However, initiating treatment with quercetin did not induce transformation without subsequent TPA treatment. Quercetin inhibited the promotion caused by 0.49 microM TPA in the transformation initiated by 1.9 microM 2-methylcholanthrene (MCA). The inhibitory effect of 30 microM quercetin was 56% in the number of foci per dish. Thus quercetin was found to have initiating effect on the transformation of BALB/3T3 cells, but to restrain the promotion by TPA. 相似文献
173.
S Hosokawa H Shinoda T Sakai M Kato Y Kuroiwa 《Journal of neurology, neurosurgery, and psychiatry》1987,50(7):877-881
Physiological studies on three women with limb myokymia were carried out. The patients had diabetic neuropathy, neuromyotonia, and autonomic polyneuropathy, respectively. The EMG discharge pattern, coincident with myokymia, in a patient with myokymia and neuromyotonia differed from those with myokymia without neuromyotonia. In only the first patient did the electrical stimulation of nerves evoke "late repetitive response" (LRR), which resembled the wave forms of the myokymic discharge. Epidural and peripheral nerve blocks abolished myokymia in the first and second cases, but peripheral nerve block was without effect in the third patient. These findings indicate that myokymia originates in multiple sites of alpha motor neurons and that the pathophysiology may vary. 相似文献
174.
Blood concentrations of 14C-rokitamycin (14C-TMS-19-Q) reached their peaks at 1 hour after a single oral (200 mg/kg) administration to male and female rats, and they were 28.0 +/- 0.8 and 24.9 +/- 2.0 micrograms/ml, respectively. No significant differences were observed between male and female in AUC values or maximum blood concentrations. The distribution of TMS-19-Q was good, and concentrations of 14C were high in liver, kidney, spleen, pancreas, adrenal, pituitary gland, thyroid, trachea, exorbital lacrimal gland, submaxillary gland and bone marrow. During the 72 hours period after a single oral (200 mg/kg) administration of 14C-TMS-19-Q to male rats, 8.0 and 89.6% of the dose were excreted in urine and feces, respectively and a total recovery rate was 97.5% of the dose. During the 48 hours period after a single intraduodenal (200 mg/kg) administration of 14C-TMS-19-Q in male rats, 6.9 and 36.2% of the dose were excreted in urine and bile, respectively. Reabsorption of 14C excreted from the bile was negligible. Absorptions of TMS-19-Q from the duodenum, jejunum, ileum and colon were good, but absorption from the stomach was negligible. Major metabolic reactions of TMS-19-Q were deacylation and hydroxylation, and the major metabolites in rats of TMS-19-Q found in the plasma, urine and bile after oral and intraduodenal administration were 10"-OH-TMS-19-Q, leucomycin A7, leucomycin V and 14-OH-leucomycin V. 相似文献
175.
Y Tomino H Sakai B Basolo I Aarons A R Clarkson 《The Tokai journal of experimental and clinical medicine》1986,11(4):235-239
Correlation of paramesangial deposits ("hemispherical body") and glomerular sclerosis and/or hyalinosis was examined by light microscopical analysis in 40 patients of IgA nephropathy. Correlation of paramesangial deposits and intensity of IgA or C3 deposition in glomeruli was also evaluated in these patients. The number of paramesangial deposits was markedly increased in patients with moderate and advanced stages of IgA nephropathy who showed marked glomerular sclerosis and/or hyalinosis. There was a significant correlation between the number of paramesangial deposits and the intensity of IgA deposits in glomeruli. It is suggested that the accumulation of paramesangial deposits might induce severe glomerular injuries such as glomerular sclerosis and/or hyalinosis. 相似文献
176.
Junko Ueshima Ryo Momosaki Akio Shimizu Keiko Motokawa Mika Sonoi Yuka Shirai Chiharu Uno Yoji Kokura Midori Shimizu Ai Nishiyama Daisuke Moriyama Kaori Yamamoto Kotomi Sakai 《Nutrients》2021,13(3)
Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions. 相似文献
177.
Hiroshi Sakai Yuka Tanaka Asuka Tanaka Hideki Ohdan 《American journal of transplantation》2021,21(4):1427-1439
Refractory B cell responses to T cell–independent (TI) carbohydrate antigens (Ags) are critical drivers of rejection reactions to ABO-incompatible allogeneic grafts and xenogeneic grafts from other species. To explore the biological significance of crosstalk between Toll-like receptors (TLRs) and B cell receptors (BCRs) in the TI B cell immunity, we here used MyD88-, TRIF-, and α-galactosyltransferase-deficient mice to study B cell phenotypes and functional properties during TI transplant–related glycan Ag exposure. BCR stimulation alone induced differentiation into CD5high (B-1a) cells, which were highly sensitive to a calcineurin inhibitor (CNI), while co-stimulation of TLRs and BCRs induced differentiation into CD5dim (B-1b) cells in MyD88-dependent and CNI-resistant manner. MyD88-dependent TLR stimulation in B-1b cells enhanced downstream factors in the BCR-calcineurin pathway, including a nuclear factor of activated T cells, cytoplasmic 1 (NFATc1). TLR inhibitor together with CNI abrogated refractory B-1b cell immune responses against the ABO-blood group Ags, while blocking both BCRs and TLR-MyD88 by using Bruton's tyrosine kinase inhibitor and histone deacetylase inhibitor abrogated refractory B-1b cell immune responses against Gal-glycan Ags. Thus, this study provides a rationale for a novel therapeutic approach to overcome refractory transplant-related anti-glycan Ab production by blocking both BCR and TLR-MyD88 signals. 相似文献
178.
J Tamaoki N Sakai K Isono T Kanemura A Chiyotani F Yamauchi T Takizawa K Konno 《International archives of allergy and applied immunology》1991,95(2-3):169-173
We studied the effect of substance P (SP) on the electric properties of cultured canine tracheal epithelium and its possible modulation by neutral endopeptidase (NEP) by Ussing's short-circuited technique in vitro. Addition of SP (5 x 10(-6) M) to the mucosal side increased short-circuit current (SCC) from 5.1 +/- 0.9 to 10.3 +/- 2.2 microA/cm2 (mean +/- SE; p less than 0.01), which was accompanied by increases in transepithelial potential difference and conductance. The effect of the mucosal SP on SCC was dose-dependent, with the maximal increase from the baseline value being 5.8 +/- 1.0 microA/cm2 observed at 5 x 10(-5) M. The NEP inhibitor phosphoramidon (10(-5) M) did not affect these responses. On the other hand, SCC was not altered by the addition of SP to the submucosal side. However, it was increased dose-dependently in the presence of phosphoramidon (10(-5) M) but not in the presence of captopril, bestatin or leupeptin. This stimulatory effect of submucosal SP was abolished by furosemide, diphenylamine-2-carboxylate and Cl-free medium, but not by amiloride. These results suggest that SP may selectively stimulate Cl secretion across the airway epithelium and that this effect may be modulated by submucosal NEP. 相似文献
179.
Mori R Ochi M Sakai Y Maniwa S Kawasaki K 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(10):642-648
A new quantitative method was devised both to establish an objective standard for morphometric diagnosis and to determine the extent of degeneration in osteoarthritic cartilage. Eight normal and forty-eight osteoarthritic humeral heads, subsequently confirmed by light microscopy, were obtained at necropsy. The articular cartilage was observed in situ with a laser scanning confocal microscope (LSCM) and morphometric measurements determined cell density (cells/mm), cell volume fraction (%) and mean cell volume (microm3). The osteoarthritic cartilages were classified according to the following four characteristics: increase in thickness, increase in cell volume fraction, decrease in cell volume fraction, and fibrous pannus. Deviations in cell density and cell volume fraction from normal means were calculated as extent of degeneration. Our present approach aims to provide valuable clues, such as objective stereological information and a unique reference for biochemical and traditional morphological analyses, that clinicians will be able to use in combination with other methods in order to establish a reliable diagnosis. 相似文献
180.
We studied the pathogenesis of IRBP-induced experimental autoimmune uveoretinitis (EAU) by immunohistochemical detection of various immune cells using specific monoclonal antibodies to their surface markers and adhesion molecules. The following results were obtained: (1) During each stage of EAU, CD4 positive T cells predominated over CD8 positive T cells in the retina and the uvea. (2) One day prior to the clinical onset of disease, la positive cells began to appear in the ciliary body. (3) LFA-1 and ICAM-1 were expressed on intraocularly infiltrating cells. (4) ICAM-1 was also expressed on endothelial cells of uveal and retinal vessels. In addition, ICAM-1 was expressed on ciliary body epithelium and retinal pigment epithelium, a finding which may be associated with the breakdown of the blood-ocular barrier. In conclusion, the expression of LFA-1 and ICAM-1 in EAU demonstrates that adhesion molecules, such as these, play an important role in inflammatory ocular disease in vivo. 相似文献