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S Shinohara

Publications and source records attributed to S Shinohara.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Cytogenetic subtyping of salivary gland pleomorphic adenoma and carcinoma in pleomorphic adenoma].

Current research on salivary gland pleomorphic adenoma is aimed at grouping the cases by cytogenetical aberrations into several subtypes. In this report, 21 cases of pleomorphic adenomas were analysed cytogenetically and divided into 4 subtypes following Bullediek's method; normal karyotype (6 cases), 8q12 rearrangement (8 cases), 12q13-15 rearrangement (5 cases) and other aberrations (2 cases). The average occurrence age of each group was examined. The 8q12 rearrangement group (37.2 y.o.) was younger than the normal karyotype (49.2 y.o.) and 12q13-15 rearrangement groups (52.4 y.o.). Histological subtyping based on Seifert's classification was made and its relationship with the above cytogenetic subtypes was studied. In the 8q12 rearrangement group, Seifert's type-1 was predominant (88%), while in the normal karyotype and 12r13-15 rearrangement groups, Seifert's type-2 was the most common (50% and 80% respectively). We also examined 2 cases of carcinoma in pleomorphic adenoma. Although both showed some cytogenetic abnormalities, no aberrations specific to pleomorphic adenoma (8q12 or 12q13-15 rearrangement) were found. This suggests that original adenomas of these carcinomas showed a normal karyotype or other types of aberrations.

Adenocarcinoma↗
PubMed1994

Combined effects of diltiazem and oxygen in pulmonary hypertension of mixed connective tissue disease.

A 45-year-old woman with pulmonary hypertension and mixed connective tissue disease (MCTD) underwent right heart catheterization to evaluate the effects of vasodilators. Nasal oxygen at 2 l/min in addition to 300 mg diltiazem improved pulmonary hemodynamics without adverse effects. After 1 year of diltiazem and home oxygen, sustained favorable hemodynamic effects were obtained, which were more marked than the acute effects. We conclude that this combination may be a potent treatment for pulmonary hypertension in patients with MCTD.

Adult↗
PubMed1993

Melatonin release from pineal cells of diurnal and nocturnal birds.

Melatonin release from the pineal cells of chicks, pigeons and crows (diurnal birds) in vitro was compared with that from owls (a nocturnal bird). The pineal cells of diurnal birds secreted large amounts of melatonin during the dark period, whereas owl pineal cells released virtually no melatonin over 24 h and did not respond to exogenous stimulant agents. Histological examination revealed that the owl pineal gland is very small and has a poor vascular network. These results suggest that the pineal gland of owls may have degenerated and is not involved in the circadian clock mechanism in this species.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1993

Bidirectional modulation of human B cell stimulation by activated T cells.

Although human T cells have been shown to exert effects of both help and suppression on B cells, the precise sequelae for these different effects have not yet been delineated. The present study therefore examined in detail the functions of human peripheral blood T cells activated for various periods by immobilized anti-CD3 to modulate B cell responses. CD4+ (CD45RA+ or CD45RA-) or CD8+ (CD45RA+ or CD45RA-) T cell subsets were cultured in wells with immobilized anti-CD3 for as long as 20 days. At various periods of time, these activated T cells were harvested and cocultured with either fresh resting B cells or preactivated B cells. CD4+ and CD8+ T cells, irrespective of their expression of the CD45RA molecule, were able to stimulate resting B cells to express transferrin receptor (CD71) and IL-2 receptor (CD25) up to 17 days after activation with immobilized anti-CD3, although CD8+ but not CD4+ T cell subsets appeared to become less potent in stimulating resting B cells after 17 days of activation. By contrast, these CD4+ and CD8+ T cell subsets activated by immobilized anti-CD3 suppressed the maturation of the B cells preactivated with anti-CD3-stimulated CD4+ T cells, at the same time as when they provided help for resting B cells. The suppression, but not the help, was abrogated by treatment of the T cells with mitomycin C up to 13 days after activation. The suppression was not abrogated by addition of exogenous IL-2, irrespective of the length of stimulation of suppressor-effector T cells. These results indicate that human activated T cells can provide help and suppression simultaneously, irrespective of their phenotypes. Moreover, the data suggest that the state of activation of B cells might be important in determining the functions of the activated T cells.

Adult↗
PubMed1993

Association between blood polychlorinated biphenyl concentration and serum triglyceride level in chronic "Yusho" (polychlorinated biphenyl poisoning) patients.

The association between blood polychlorinated biphenyl (PCB) concentration and serum triglyceride level was investigated in 259 "Yusho" patients (PCB poisoning) who underwent health examinations for Yusho in 1988. Geometric means of PCB and triglyceride were 3.84 ppb (95% confidence interval: 3.54-4.17) and 114.3 mg/dl (106.6-122.6), respectively. Both correlation and multiple regression analyses showed a weak but statistically significant correlation between these two variables. The mean triglyceride level adjusted for age and sex was then calculated for comparison among four PCB levels, using analysis of covariance. This indicated a progressive increase with increasing PCB: 98.36, 117.78, 117.84, and 127.65 mg/dl at < 2.7, 2.7+, 4.1+, and 6.1+ ppb, respectively (F = 2.01, P = 0.113). Comparing PCB levels, the difference in adjusted mean triglyceride levels was marginally significant between the first and second (P = 0.088), and the first and third quartiles (P = 0.066), and reached significance between the first and fourth quartiles (P = 0.021). Thus, a weak but significant association between blood PCB and serum triglyceride was observed in the patients 20 years after exposure, although their blood PCB and serum triglyceride were relatively close to the normal levels.

Adult↗
PubMed1993

[Analysis of the state of patients with rheumatoid arthritis using a personal computer].

The present study was designed to analyze the state of 203 patients with rheumatoid arthritis (RA) in our clinic using a personal computer. The duration of the disease was significantly correlated with the progression of radiographical stages of RA, indicating that no drugs were able to prevent the progression of joint destruction. Nevertheless, bucillamine, a newly developed anti-rheumatic drug, was found to be effective in some patients who did not respond to D-penicillamine, but not vice versa. Although seropositive RA patients had more severe disease than seronegative RA patients, serum rheumatoid factor levels were not significantly correlated with Lansbury indices in seropositive RA patients. Overall, either the liver function or the renal function was not significantly affected in any category of the patients. Taken together, it is suggested that analysis of the data of the RA patients with personal computer systems provide useful information on the management of the RA patients.

Age Factors↗
PubMed1993

[Laboratory findings in the medical examination of chronic "Yusho" (PCB poisoning) patients: with special reference to blood PCB and serum triglyceride].

Associations of blood PCB concentration with serum levels of triglyceride, gamma-GTP, total-, and conjugated-bilirubin were investigated in "Yusho" patients twenty years after outbreak, using the information obtained from the medical examinations in 1988 and 1989. Study subjects were 259 patients in 1988, and 268 patients in 1989, including 190 patients who consecutively received both examinations. Blood PCB concentrations (mean +/- SE) were 4.78 +/- 0.22 ppb in 1988, and 4.47 +/- 0.17 ppb in 1989. The results of blood-chemical analysis were compared among four categorized concentrations of blood PCB, using the analysis of variance. Significant difference was observed for triglyceride (1988: p < 0.025, 1989: p < 0.005), but not for gamma-GTP, total-, and conjugated-bilirubin. In 1988, the mean triglyceride levels were 108, 137, 145, and 166 mg/dl at < 2.7, > or = 2.7, > or = 4.1, and > or = 6.1 ppb of blood of PCB, respectively. Corresponding figures in 1989 were 106, 129, 154, and 156 mg/dl at < 2.7, > or = 2.7, > or = 4.0, and > or = 5.7 ppb of blood PCB, respectively. Thus, clear positive association between blood PCB and serum triglyceride was observed in the patients twenty years after exposure.

Aged↗
PubMed1992

Inhibitory effect of CCK-8 and ceruletide on glutamate-induced rises in intracellular free calcium concentrations in rat neuron cultures.

To study the mechanism by which cholecystokinin octapeptide (CCK-8) and its potent analogue, ceruletide, prevent glutamate-induced neuronal cell death in rat neuron cultures, we examined the effect of both peptides on glutamate-induced increases in the intracellular free calcium concentrations ([Ca2+]i), which are known to be a crucial trigger of the neurodegeneration induced by glutamate. CCK-8 itself did not alter [Ca2+]i in rat neuron cultures. Glutamate increased [Ca2+]i in neuron cultures rapidly and markedly. CCK-8 and ceruletide significantly suppressed the increases in [Ca2+]i induced by glutamate. The maximum inhibitory effects of CCK-8 and ceruletide at 10(-6) M reached 43 and 46% of the response to glutamate, respectively. Gastrin-I and CCK-4 also significantly attenuated the increases in [Ca2+]i induced by glutamate. The inhibitory effect of CCK-8 was completely blocked by the selective antagonist for CCK-B receptors, (+)L-365,260, but not by (-)L-364,718, which is a selective antagonist for CCK-A receptors. CCK-8 significantly suppressed [Ca2+]i response to kainate and high concentrations of extracellular K+, but not to N-methyl-D-aspartate. With cultured astrocytes, CCK-8 did not inhibit the increment of [Ca2+]i induced by glutamate. These findings clearly demonstrated that CCK-8 and ceruletide inhibit glutamate-induced increases in [Ca2+]i in neuron cultures through CCK-B receptors, suggesting that CCK-8 may participate in the central actions of glutamate.

Animals↗
PubMed1992

Systemic administration of a cholecystokinin analogue, ceruletide, protects against ischemia-induced neurodegeneration in gerbils.

The neuroprotective action of a cholecystokinin octapeptide analogue, ceruletide, was evaluated in models of cerebral ischemia using Mongolian gerbils. Ceruletide significantly suppressed the hyperactivity and amnesia induced by ischemia when injected s.c. 30 min before 5-min occlusion of the bilateral common carotid arteries at room temperature or immediately after their reperfusion. Ceruletide also reduced behavioral changes in ischemic gerbils whose body temperature was maintained at 37 degrees C during the 3-min occlusion. In these groups, delayed neuronal cell death in the hippocampal CA1 area following ischemia was markedly attenuated by s.c. administration of ceruletide. On the other hand, ceruletide could not inhibit the behavioral changes or the neurodegeneration induced in the hippocampal CA1 area by 5-min occlusion at 37 degrees C. These findings indicate that peripheral injection of ceruletide produces a neuroprotective action against moderate cerebral ischemia, which is the first evidence suggesting the efficacy of ceruletide in neurodegenerative diseases.

Amnesia↗
PubMed1992

Regulation of B cell function by lobenzarit, a novel disease-modifying antirheumatic drug.

OBJECTIVE: Lobenzarit (disodium 4-chloro-2,2'-iminodibenzoate [CCA]) is a novel disease-modifying drug for the treatment of rheumatoid arthritis (RA). Although its clinical efficacy has been demonstrated, its mechanism of action remains unclear. We therefore examined the effects of CCA on in vitro IgM and IgM rheumatoid factor (IgM-RF) production by human B cells. METHODS: IgM and IgM-RF production was induced from highly purified B cells from 8 healthy donors by stimulation with Staphylococcus aureus Cowan 1 (SAC) plus factors generated from mitogen-activated T cells (TCF) or with immobilized anti-CD3-activated CD4+ T cells. RESULTS: CCA suppressed the production of IgM-RF as well as IgM at concentrations of 25-50 micrograms/ml (therapeutic serum concentrations of the drug), although the IgM-RF production induced by SAC plus TCF was suppressed at lower concentrations of CCA (1-3 micrograms/ml). Whereas CCA suppressed interleukin-2 (IL-2) production by anti-CD3-activated CD4+ T cells, its suppressive effects on B cells were not overcome by addition of IL-2 or TCF. CCA did not inhibit the initial stages of B cell activation in either culture system, but rather, suppressed the maturation of previously activated B cells. Cell cycle analysis by acridine orange staining indicated that CCA-mediated inhibition of B cell responsiveness induced by anti-CD3-activated CD4+ T cells was the result of a block at the G1-S interphase. CONCLUSION: These results indicate that CCA suppresses the production of IgM and IgM-RF by directly inhibiting activated B cells. Thus, one of the actions of CCA in RA may be the suppression of the function of activated B cells.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1992

Echocardiographic evaluation of pulmonary arterial hypertension in patients with progressive systemic sclerosis and related syndromes.

In order to evaluate the usefulness of echocardiography in detection and characterization of pulmonary arterial hypertension (PAH) in scleroderma patients, we performed M-mode, two-dimensional, and Doppler echocardiography in 71 patients with progressive systemic sclerosis (PSS) and related syndromes: mixed connective tissue disease (MCTD) and overlap syndromes. We estimated systolic pressure gradients across the tricuspid valve from the peak velocity of tricuspid regurgitation (TR) by color-flow guided continuous wave Doppler. TR velocities of analyzable quality for gradient estimation were obtained in 28 patients (39%), of whom 12 showed PAH (peak TR velocity > or = 2.5 m/sec). In comparison, analyzable TR was recorded in 19 (35%) of 55 patients with left-sided cardiac disease. None of the 12 with Doppler-estimated PAH showed left ventricular dilatation or decreased fractional shortening by M-mode and two-dimensional measurements. Nonsimultaneous cardiac catheterization confirmed PAH in 8 of 9 with Doppler-estimated PAH and in 3 of 12 without analyzable TR who had hemodynamic study. Doppler-estimated right ventricular systolic pressures (RVSP) correlated well with catheterization-measured pulmonary arterial systolic pressures (PASP) (< 0.01). Our results indicate that Doppler echocardiography is useful in detecting subclinical PAH and estimating PASP in patients with collagen vascular disease. The results of pulmonary function studies suggest that PAH in MCTD is mainly caused by pulmonary vasculopathy.

Adult↗
PubMed1992

Phenotypic analysis of peripheral blood monocytes isolated from patients with rheumatoid arthritis.

The expression of CD14, Fc gamma receptor I (Fc gamma RI), Fc gamma RII, and HLA-DR on peripheral blood monocytes from patients with rheumatoid arthritis (RA) was studied to investigate their nature and their role in the pathogenesis of rheumatoid synovitis. Peripheral blood mononuclear cells obtained from 9 patients with active RA, 8 patients with RA in complete remission, and 14 healthy individuals, were stained with various monoclonal antibodies and analyzed on a fluorescence activated cell sorter. The expression of CD14 as well as Fc gamma RI and Fc gamma RII was upregulated on peripheral blood monocytes from patients with active RA, although the expression of HLA-DR was not increased. In addition, the expression of Fc gamma RI and Fc gamma RII on monocytes was still upregulated in patients with RA in complete remission, whereas the expression of CD14 on monocytes was normalized in these patients. These results indicate that peripheral blood monocytes in patients with active RA are already activated to express higher densities of CD14. In addition, our observation that CD14 density was increased on a subset of circulating blood monocytes in active RA, that HLA-DR was not significantly altered and that Fc gamma RI and Fc gamma RII were increased in both active and inactive RA is not compatible with the expected actions of interferon gamma. Finally, it is suggested that peripheral blood monocytes in patients with RA may have intrinsic abnormalities as evidenced by the enhanced expression of Fc gamma R, which is repeatedly observed regardless of the disease activity of RA.

Adult↗
PubMed1992

Isolation of adult pig islet. In vitro assessment and xenotransplantation.

This study was conducted to develop an isolation method for adult pig islets and to investigate in vivo function after xenotransplantation as well as in vitro function of isolated islets. From the splenic portion of the glands (n = 20), 3277 +/- 645 islets per gram of pancreas were isolated and recovered by a five-step dextran discontinuous density gradient method. Purity of the final preparation obtained from 20 different consecutive pig pancreata was 80-90%. In vitro incubation study revealed a significant insulin release from isolated adult pig islets in response to glucose stimulation. In vitro perifusion study demonstrated a biphasic insulin response to glucose stimulation from isolated islets. Xenotransplantation of approx 2000 isolated adult pig islets into the portal vein of diabetic Wistar rats (n = 8) significantly reduced serum glucose levels from 431 +/- 24 mg/dL to 173 +/- 18 mg/dL 24 h after transplantation. This study provides a development of an isolation method for adult pig islets and demonstrates that isolated islets are viable and functioning both in vitro study and in vivo study of xenotransplantation.

Animals↗