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Biomedical subjects

S Shintani

Publications and source records attributed to S Shintani.

At least 127 records · Page 7Linked to original sources
PubMed1990

Inhibition of type 1 diabetes in BB rats with recombinant human tumor necrosis factor-alpha.

We previously reported that streptococcal preparation (OK-432), which is a TNF inducer, inhibits insulitis and development of autoimmune diabetes in nonobese diabetic (NOD) mice and Bio-Breeding (BB) rats, as animal models of insulin-dependent diabetes mellitus. We have recently shown that recombinant human (h)TNF-alpha also suppresses development of diabetes in NOD mice. In this study we have extended our observation on TNF to BB rats in order to see whether TNF generally inhibits autoimmune diabetes. A total of 5 x 10(4) U of rhTNF-alpha was administered i.p., twice a week to male and female BB rats from 4 to 27 wk of age. The cumulative incidence of diabetes by 27 wk of age in nontreated rats was 36.4% (8/22), whereas that in hTNF-alpha-treated rats was 0% (0/21) (p less than 0.001). The hTNF-alpha-treated rats did not lose body weight and maintained normal blood glucose concentrations. Immunologic and histologic examinations were performed at the end of the experiment. Spleen cell cytotoxicities for NK-sensitive YAC-1 and rat insulinoma (RINm5F) cells in hTNF-alpha-treated rats significantly decreased in comparison with nontreated and nondiabetic BB rats. Intensity of insulitis was also inhibited in hTNF-alpha-treated rats. Interestingly, a huge hepatomegaly and splenomegaly was found in two of the 21 hTNF-alpha-treated rats. The latter consisted of W3/13dull+ and W3/25dull+ cells, which did not exhibit cytotoxicity for either YAC-1 or RINm5F cells. These results indicate that the chronic and systemic administration of TNF has a regulatory role in autoimmune diabetes in BB rats as well as in NOD mice, and that these animals may have a defect in TNF-mediated immunoregulation.

Animals↗
PubMed1990

Mechanism of action of a streptococcal preparation (OK-432) in prevention of autoimmune diabetes in NOD mice. Suppression of generation of effector cells for pancreatic B cell destruction.

We have previously reported that treatment with a streptococcal preparation (OK-432), one of the biologic response modifiers, inhibits insulitis and development of autoimmune diabetes in nonobese diabetic (NOD) mice and Bio-Breeding rats used as animal models of insulin-dependent diabetes mellitus (IDDM). We studied the mechanism by which OK-432 inhibited development of IDDM in NOD mice. In female NOD mice diabetes spontaneously developed from 10 to 15 wk of age and the cumulative incidence of diabetes amounted to 74.7% at 30 wk of age. NOD mice, however, never developed diabetes over the observation period of up to 45 wk of age when they were i.p. injected with 0.1 mg of OK-432 weekly from 4 to 15 wk of age. OK-432 treatment in younger age had a stronger inhibitory effect on the development of diabetes. Diabetes was transferred to young, irradiated mice by spleen cells of nontreated, adult mice, but barely transferred by those of OK-432-treated mice. Furthermore, these spleen cells of OK-432-treated mice did not suppress transfer of diabetes by diabetic mice spleen cells. Treatment with cyclophosphamide promoted development of diabetes in nontreated NOD mice due to removal of suppressor cells. However, cyclophosphamide did not show the promotive effect in OK-432-treated mice. Taken together, these results indicate that OK-432 treatment prevented development of diabetes mainly by suppression in generation of the effector cells for pancreatic B cell destruction. The same OK-432 treatment did not suppress the immune response to exogenous AG such as xenogeneic SRBC and allogeneic tumor cells. The study suggests that BRM in the natural environment such as streptococci may suppress induction and progression of autoimmunity and be useful for the immunotherapy of human IDDM.

Animals↗
PubMed1990

Tuberculous brain infection located in an old cerebral infarct: CT changes with successful conservative therapy.

A case of tuberculous brain infection following tuberculous meningitis in a 67-year-old man is presented. It was located in an old cerebral infarct associated with left internal carotid artery occlusion. CT demonstrated capsule enhancement in the left temporal area after iodinated contrast medium. Chemotherapy with INH, RFP and SM diminished the lesion and the capsule disappeared thirteen months later. It is suggested that a relatively long clinical history together with the appearance of a thick-walled abscess-like lesion on the CT scan is consistent with the diagnosis of tuberculous brain infection, perhaps an abscess.

Aged↗
PubMed1990

Acute effect of parathyroid hormone-(1-34) fragment on blood pressure in rats fed a low calcium diet.

1. Acute effects of human PTH-(1-34) fragment on blood pressure were examined in rats fed a low or normal calcium diet. 2. Plasma biochemistry showed that a low calcium diet evoked hyperparathyroidism as well as hypocalcemia in rats. 3. Subcutaneous administration of human PTH-(1-34) caused a significant decrease in tail-cuff systolic blood pressure in rats fed a normal calcium diet, but not in rats fed a low calcium diet. 4. Intravenous administration of human PTH-(1-34) reduced the arterial blood pressure in rats, dose-dependently. The reduction of blood pressure was more pronounced in rats fed a normal calcium diet than that in the rats fed a low calcium diet. 5. It is suggested that the hypotensive action of human PTH-(1-34) was more pronounced in the rats fed a normal diet than in the rats fed a low calcium diet, and that PTH has different cardiovascular consequences under chronic hyperparathyroidism and/or hypocalcemia.

Animals↗
PubMed1990

"Pseudo-delta sign" on computed tomography in an extremely acute stage of superior sagittal sinus thrombosis--a case report.

A case of superior sagittal sinus (SSS) thrombosis with a "pseudo-delta sign" on computed tomography (CT) is reported. The so-called "empty delta sign," which usually appears following contrast enhancement, is reliable in the CT diagnosis of SSS thrombosis but may not appear, it is said, in the extremely acute stage. In this patient, however, the "empty delta sign" appeared with precontrast CT scans and disappeared with postcontrast CT scans, "pseudo-delta sign," in the extremely acute stage of SSS thrombosis. On the precontrast CT, blood surrounding the sagittal sinus outlined it; when contrast was given, it became dense with blood.

Acute Disease↗
PubMed1989

Recombinant human tumor necrosis factor alpha suppresses autoimmune diabetes in nonobese diabetic mice.

We previously reported that administration of a streptococcal preparation (OK-432) inhibited insulitis and development of autoimmune diabetes in nonobese diabetic (NOD) mice and BB rats as animals models of insulin-dependent diabetes mellitus. In this study, we screened various cytokines that could be induced by OK-432 in vivo, for their preventive effect against diabetes in NOD mice. Among recombinant mouse IFN gamma, human IL1 alpha, human IL2, mouse granulocyte-macrophage colony-stimulating factor and human TNF alpha, only human TNF alpha suppressed insulitis and significantly (P less than 0.001) inhibited development of diabetes. NOD mice were the lowest producers of the mRNA of TNF and serum TNF on stimulation with OK-432 or with IFN gamma plus LPS, compared with C57BL/6, C3H/He, and Balb/c mice. The results imply a role for low productivity of TNF in the pathogenesis of autoimmune diabetes in NOD mice.

Animals↗
PubMed1989

[Sleep apnea in well-controlled myasthenia gravis].

UNLABELLED: Polygraphic monitoring of the respiratory status during sleep provides a definitive test for the presence of the sleep apnea syndrome. This syndrome has been recognized in various kinds of neurological disorders. However, as far as we know, there have been no reports of describing the sleep apnea syndrome in myasthenia gravis (MG). We conducted overnight polygraphic sleep studies of 10 patients of clinically well-controlled MG. PATIENTS: We examined 10 patients of MG (4 men and 6 women). The subtypes of MG were IIA(1), IIB(8) and V(1) according to Osserman's criteria. RESULTS: Six patients, with an average age of 47.8 and the average duration of 6.2 years, had polysomnographically obstructive and central types of sleep apnea, appearing longer than 10 seconds and more than 30 times in one night. Their mean Apnea Index (AI) was 14.6. The duration of mean apnea was 23.4 seconds and 99.0 times the average frequency. On the other hand, in four patients of MG, averaged age at 30.8 and for a 0.9-year duration, the sleep apnea syndrome was never seen. Therefore, the longest duration of MG tended to have the sleep apnea syndrome. DISCUSSION: Six out of the 10 patients of MG had obstructive and central types of the sleep apnea syndrome. Since their respiratory functions examined in a daytime were normal and the physical findings concerned with MG were well controlled by medications, our findings of nocturnal sleep apnea might be indicative of a central cholinergic system disturbance in MG during sleep.

Adult↗
PubMed1988

Peripheral neuropathy with predominantly motor manifestations in a patient with carcinoma of the uterus.

An autopsy case of a 56-year-old woman who had carcinoma of the corpus uteri and peripheral neuropathy with predominantly motor manifestations is described. The neurological abnormalities included subacute weakness of the limbs and loss of deep reflexes, which improved after the surgical removal of the uterine carcinoma. Neuropathologically, peripheral nerves mainly presented features of axonal degeneration with a mild loss of myelinated fibres. Anterior horns of the spinal cord showed central chromatolysis of the motor nerve cells and many spheroids without neuronal loss. Axonopathy of peripheral nerves was considered to be the main pathological process in this paraneoplastic syndrome.

Carcinoma↗
PubMed1988

NOD mice with high incidence of type 1 diabetes are not T lymphocytopenic.

An autoimmune pathogenesis has been indicated in insulin-dependent (type 1) diabetes mellitus (IDDM). Previously we reported that non-obese diabetic (NOD) mice as an animal model of spontaneously developing IDDM were immunologically characterized by T lymphocytopenia and impaired cellular immunities. The cumulative incidence of diabetes in the T lymphocytopenic female NOD mice was 10-20% by 24 weeks of age. On the other hand, the incidence of diabetes are 80-90% in the female NOD/Shi-Sendai (S), in whom proportion of lymophocyte subsets has not been known yet. Therefore, we examined the spleen cells of female NOD/Shi-S and female NOD/Shi with high incidence of diabetes, and of female Jcl:ICR as a control. Cell numbers, populations of T cells (Thy 1.2+, Lyt-1+ and Lyt-2+), B cells (surface-Ig+), NK cells (acialo GM1+) and responsiveness to Concanavalin A were analyzed as immunological parameters. In contrast to the T lymphocytopenic NOD, these immunological parameters were not impaired in the NOD/Shi-S and NOD/Shi in comparison to those of Jcl:ICR. The results indicate that there may be a positive association between the incidence of diabetes and T cell number and functions in female NOD mice.

Animals↗
PubMed1988

Treatment with streptococcal preparation (OK-432) suppresses anti-islet autoimmunity and prevents diabetes in BB rats.

We have recently shown that a streptococcal preparation (OK-432) inhibits insulitis and prevents diabetes in nonobese diabetic (NOD) mice, an animal model of insulin-dependent diabetes mellitus (IDDM). We extended this study to another model of IDDM, namely BB rats. Male and female BB rats were injected weekly with 0.2 mg OK-432 i.p. starting from 5 to 6 wk and continuing through 20 or 30 wk of age. The cumulative incidence of IDDM over 20 wk in the OK-432-treated BB rats (4 of 54, 7.4%) was significantly (P less than .01) lower than that found in the nontreated BB rats (13 of 47, 27.7%). We examined some of these rats as follows. All of the OK-432-treated BB rats tested showed normal glucose levels before and after oral glucose administrations, as did the nontreated and nondiabetic BB rats. Histological examination of pancreatic sections revealed that the OK-432-treated rats retained a greater number of intact islets without infiltration of the mononuclear cells than did the nontreated BB rats. A preliminary in vitro study further demonstrated that the cytotoxic activities of spleen cells against a rat insulinoma cell line, RIN, were suppressed in the OK-432-treated rat. However, the treatment of BB rats with OK-432 showed no suppressive effects in the spleen cell number, the responsiveness of spleen cells to concanavalin A, the populations of OX19+, W3/25+, and OX8+ peripheral blood lymphocytes, or in the titers of cell surface antibody against RIN. These results suggest that a nonimmunosuppressive immunomodulator such as OK-432 may be useful as an agent for immunotherapy of IDDM.

Animals↗
PubMed1986

[Study of the ameliorating effects of an enteral nutrient for liver failure on hepatic encephalopathy: effects of SF-1008C on plasma and brain free amino acids, intracerebral amine concentrations and electroencephalogram in portacaval shunted rats with ammonia loading].

The ameliorating effects of an enteral nutrient for liver failure (SF-1008C), which is enriched with branched-chain amino acids (BCAA) and includes few aromatic amino acids (AAA), were investigated. The blood ammonia, plasma and brain free amino acids, intracerebral amine concentrations and electroencephalogram were measured in portacaval shunted rats with 10% ammonium acetate (3 ml/kg, i.p.) (PCS) as a model of hepatic encephalopathy. The blood ammonia and plasma free amino acid concentrations in PCS rats were significantly increased in comparison to sham-operated (Sham) rats. Thus, the plasma BCAA/AAA ratio in PCS rats was appreciably reduced. Concomitant with the abnormal plasma amino acid concentrations, the brain free amino acid concentrations in PCS rats were markedly increased in comparison to the Sham rats. Moreover, the intracerebral tryptophan (Trp) and 5-hydroxyindol acetic acid (5-HIAA) concentrations were significantly increased, and the intracerebral dopamine (DA) concentration was significantly decreased in the PCS rats. The intracerebral serotonin (5-HT) and norepinephrine (NE) concentrations were, however, hardly changed. A smaller voltage for the electroencephalogram was used in the PCS rats than in the Sham rats. Abnormal plasma and brain free amino acid concentrations in PCS rats were normalized by oral administration of SF-1008C, and the low voltage electroencephalograms in the PCS rats were suppressed. On the other hand, abnormal plasma and brain free amino acid concentrations in the PCS rats were hardly normalized by oral administration of ED-AC, an elemental diet based on an amino acid composition of egg protein. These results suggest that SF-1008C affects brain free amino acids, intracerebral amine concentrations and electroencephalogram by ameliorating abnormal plasma free amino acid concentrations. Moreover, there is a highly significant correlation between the plasma BCAA/AAA ratio and the brain BCAA/AAA ratio, and this finding suggests that the plasma free amino acid patterns reflect the brain free amino acid patterns.

Amino Acids↗
PubMed1986

Streptococcal preparation (OK-432) inhibits development of type I diabetes in NOD mice.

OK-432 (a streptococcal preparation) has been widely used for cancer immunotherapy in Japan. It is the most potent immunomodulator in activating both macrophages and killer T cells and in increasing interleukin 2 production. Two K.E. (Klinische Einheit, clinical unit) of OK-432 were given intraperitoneally to each of 17 female nonobese diabetic (NOD) mice every week from 4-24 wk of age. NOD mice as well as BB rats spontaneously develop type I diabetes. During administration of OK-432, the development of diabetes was inhibited in 17 of 17 mice over the 24-wk observation period, whereas 14 of 17 female NOD mice given physiological saline had developed diabetes by 24 wk of age. At the onset of diabetes, nonfasting blood glucose was 511 +/- 82 mg/dl. Histologic examination showed that in the OK-432-treated NOD mice, 98% of total islets were intact or mildly infiltrated with mononuclear cells, whereas in saline-treated NOD mice, 79% of total islets exhibited severe insulitis. In OK-432-treated NOD mice, both the number of the mononuclear spleen cells and their natural killer cell activity was significantly increased.

Animals↗