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T Toyota

Publications and source records attributed to T Toyota.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Current concept of the pathogenesis of autoimmune type 1 diabetes mellitus].

In type 1 diabetes, the beta cell is selectively destroyed by T lymphocytes in a genetically susceptible individual. Susceptible HLA-class II molecules which have low binding affinity with putative beta cell antigens may fail in induction of self-tolerance. beta cell-reactive T cells may expand and infiltrate around the islet (benign insulitis) by stimulation with environmental factors through molecular mimicry and/or beta cell antigens per se. Benign insulitis may develop to destructive insulitis under overexpression of Th1 cytokines, which may be affected by non-MHC genes. Immune interventions to shift a cytokine balance to Th2 dominance in the insulitis lesion may be most realistic approach to suppress development of type 1 diabetes after the induction of autoimmunity.

Animals↗
PubMed1999

[Sulfonylurea drug--a new sulfonylurea drug for type 2 diabetes].

The incidence of diabetes mellitus has been increased year by year and now 5-6 millions are diabetic patients in Japan. Studies of DCCT and UKPDS concluded that tight control of diabetes was benefit for prevention of diabetic complications in type 1 and type 2 diabetes, respectively. New type of sulfonylurea (glimepiride) has been developed by Hoechst Marion Roussel company which continues clinical trials in Japan. Grimepiride is an insulin sparing sulfonylurea drug for the treatment of type 2 diabetes patients whose high blood glucose cannot be controlled by diet and exercise alone. In Europe and United State glimepiride has been used as a monotherapy or in combination with insulin. Glucose control was effectively observed in type 2 diabetics including obese and hypertensive patients by the drug. Mechanism of sulfonylurea which stimulates insulin release is supposed by binding to a regulatory subunit of plasma membrane ATP-sensitive K+ (KATP) channel. The consequent closure of KATP channel leads to depolarization, opening of voltage-dependent Ca2+ channels, Ca2+ influx, and a rise in intracellular [Ca2+], resulting in insulin secretion. However, it has been suggested that sulfonylurea may have an additional action on secretion, independent of changes in intracellular [Ca2+] but dependent on the activity of protein kinase C (PKC). It is controversial whether or not sulfonylurea is a risky drug to the process of diabetic macroangiopathy, by suppressing KATP channels in the heart.

Diabetes Mellitus, Type 2↗
PubMed1999

[Inflammatory bowel disease and pregnancy: clinical study of mutual influence, clinical course and treatment].

We studied the clinical courses of 70 pregnancies in 47 women with ulcerative colitis (UC) and 18 pregnancies in 12 women with Crohn's disease (CD) retrospectively. We concluded as follows. 1. Pregnancy has less influence on the course of UC. 2. The patients with UC who kept remission for more than 1 year before conception have less risk of relapse and severity during pregnancy. 3. The patients with active UC at the time of conception tend to worsen during pregnancy. The patients whose onset of UC is during pregnancy tend to worsen. 4. UC has a little influence on the course of pregnancy except severe active disease. 5. It is not obtained that pregnancy becomes a relapsing factor of CD. 6. CD during pregnancy has little influences on the course of pregnancy, if it is remitted. 7. Salazosulfapyridine and corticosteroids therapy has less influence on the fetus and the course of pregnancy.

Adrenal Cortex Hormones↗
PubMed1999

[The expression of chemokines and the dynamics of inflammatory cell infiltration before and after H. pylori eradication].

We attempted to evaluate the relationship between the expression of IL-8 and RANTES and the dynamics of their target cells in human gastric mucosa of H. pylori associated gastritis, including their changes after H. pylori eradication. We performed the measurement of the mucosal level of IL-8 and RANTES protein by ELISA and immunohistochemistry. The neutrophil infiltration into the gastric mucosa was identified by the histological examination based on the Updated Sydney system and the measurement of MPO activity. The memory T lymphocyte and eosinophil were indicated by immunohistochemistry of CD45RO that is one of surface markers indicating memory T lymphocytes and MBP that is contained in the granules of eosinophils. H. pylori positive gastric mucosa demonstrated a remarkable increase in neutrophils. CD45RO positive cells and eosinophils, compared to H. pylori negative gastric mucosa. Gastric mucosal level of IL-8 and RANTES protein and MPO activity was significantly higher in H. pylori positive cases than that in H. pylori negative controls after H. pylori eradication, both of the level of IL-8 protein and MPO activity reduced at the same levels as negative controls. However, RANTES expression, CD45RO positive T lymphocytes and eosinophils remained in H. pylori eradicated gastric mucosa at the significantly high level, compared with H. pylori negative cases. Therefore, it seems possible that IL-8 might enhance the inflammation by facilitating the neutrophil infiltration into H. pylori infected gastric mucosa and that RANTES might play an important role in the specific immune response against H. pylori and the maintenance of the immune memory after H. pylori eradication.

Adult↗
PubMed1999

Host immune profiles and genotyping analysis of HIV-1 among Japanese hemophiliac patients.

We studied the immune profiles of 21 Japanese hemophiliac patients who had been infected with human immunodeficiency virus type 1 (HIV-1) by the blood preparations during the 1982-84 period, and carried out the genotyping of HIV-1 V3 region for uncultivated peripheral blood mononuclear cells (PBMC) from 8 patients. Ten years after infection, asymptomatic carrier (AC, 14 cases) yet outnumbered those in AIDS related complex (ARC, 4 cases) and AIDS (3 cases), and the CD4+ and CD8+ T-cell numbers were not correlated with clinical stages. Macrophage tropic sequences, as identified according to the known tropism determinants, appeared to be more frequent as the CD4+ T-cell numbers were higher. There was no correlation of the cell tropism with the disease stages, however. It might be due to HIV-1 of CD4+ T-cells being more productive. The mutation in the V3 region appears to differentially influence the escape from antibody attack and clinical stages, and the cell tropism may not be related to the cell immunity of the host.

Adolescent↗
PubMed1999

[Neurotensin].

Explore the source record for details and available documents.

Humans↗
PubMed1998

Autoantibodies against CD38 (ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase) that impair glucose-induced insulin secretion in noninsulin- dependent diabetes patients.

Cyclic ADP-ribose (cADPR) has been shown to be a mediator for intracellular Ca2+ mobilization for insulin secretion by glucose in pancreatic beta cells, and CD38 shows both ADP-ribosyl cyclase to synthesize cADPR from NAD+ and cADPR hydrolase to hydrolyze cADPR to ADP-ribose. We show here that 13.8% of Japanese non-insulin-dependent diabetes (NIDDM) patients examined have autoantibodies against CD38 and that the sera containing anti-CD38 autoantibodies inhibit the ADP-ribosyl cyclase activity of CD38 (P </= 0.05). Insulin secretion from pancreatic islets by glucose is significantly inhibited by the addition of the NIDDM sera with anti-CD38 antibodies (P </= 0.04-0.0001), and the inhibition of insulin secretion is abolished by the addition of recombinant CD38 (P </= 0.02). The increase of cADPR levels in pancreatic islets by glucose was also inhibited by the addition of the sera (P </= 0.05). These results strongly suggest that the presence of anti-CD38 autoantibodies in NIDDM patients can be one of the major causes of impaired glucose-induced insulin secretion in NIDDM.

ADP-ribosyl Cyclase↗
PubMed1998

Studies of 13C-urea breath test for diagnosis of Helicobacter pylori infection in Japan.

In recent years Helicobacter pylori infection has been implicated in the etiology of a variety of upper gastrointestinal diseases. The aim of this multi-center trial was to search for the cut-off value of the simple 13C-urea breath test (13C-UBT) for diagnosis of H. pylori infection, and to examine the sensitivity and specificity of 13C-UBT for culture, the rapid urease test (CLO test), histology, and serological tests. Two hundred and forty-eight patients participated in this study after giving their informed consent. Endoscopic biopsy specimens were taken from gastric antrum and corpus for culture (190 patients), CLO test (222 patients), and histology (98 patients). A serological test was carried out for all patients. H. pylori infection was established when culture was positive or more than two of the tests, histology, CLO test, and serological test, were positive, and non-infection status was established when the all tests more than two tests were negative. After baseline breath samples were taken, the patients (who had fasted) were given 100mg of 13C-urea in 100ml water while sitting; they washed out the mouth with water. They were then placed in the left lateral decubitus position for 5 min, and additional breath samples were taken 10, 20, 30, 45, and 60 min after urea administration, with patients in the sitting position. One hundred and sixty-five of the 248 patients were infected, 48 were not infected, and H. pylori infection status was not evaluated in 35 by endoscopic and serological tests. Breath samples at 20 min were employed to determine the cut-off value. Using the receiver operating characteristic (ROC) curve, we determined the cut-off value for a positive UBT at 2.5 delta per thousand. The sensitivities of UBT for culture, CLO test, histology, and serological test were 98.4%, 98.6%, 100.0%, and 92.5%, and the specificities were 78.8%, 82.5%, 83.3%, and 87.3%, respectively. The cut-off value of 13C-UBT for the diagnosis of H. pylori infection was 2.5 delta per thousand; this test is a simple and noninvasive method for the diagnosis of this infection and has high sensitivity and specificity.

Adult↗
PubMed1998

The effects of coenzyme Q10 treatment on maternally inherited diabetes mellitus and deafness, and mitochondrial DNA 3243 (A to G) mutation.

The characteristic clinical features of diabetes mellitus with mitochondrial DNA (mtDNA) 3243(A-G) mutation are progressive insulin secretory defect, neurosensory deafness and maternal inheritance, referred to as maternally inherited diabetes mellitus and deafness (MIDD). A treatment for MIDD to improve insulin secretory defects and reduce deafness has not been established. The effects of coenzyme Q10 (CoQ10) treatment on insulin secretory response, hearing capacity and clinical symptoms of MIDD were investigated. 28 MIDD patients (CoQ10-DM), 7 mutant subjects with impaired glucose tolerance (IGT), and 15 mutant subjects with normal glucose tolerance (NGT) were treated daily with oral administration of 150 mg of CoQ10 for 3 years. Insulin secretory response, blood lactate after exercise, hearing capacity and other laboratory examinations were investigated every year. In the same way we evaluated 16 MIDD patients (control-DM), 5 mutant IGT and 5 mutant NGT subjects in yearly examinations. The insulin secretory response assessed by glucagon-induced C-peptide secretion and 24 h urinary C-peptide excretion after 3 years in the CoQ10-DM group was significantly higher than that in the control-DM group. CoQ10 therapy prevented progressive hearing loss and improved blood lactate after exercise in the MIDD patients. CoQ10 treatment did not affect the diabetic complications or other clinical symptoms of MIDD patients. CoQ10 treatment did not affect the insulin secretory capacity of the mutant IGT and NGT subjects. There were no side effects during therapy. This is the first report demonstrating the therapeutic usefulness of CoQ10 on MIDD.

Adult↗
PubMed1998

Inhibitory effect of troglitazone on diabetic neuropathy in streptozotocin-induced diabetic rats.

Free-radical scavengers and inhibitors of tumour necrosis factor-alpha (TNF-alpha) such as N-acetylcysteine and pentoxifylline have been shown to inhibit the development of peripheral neuropathy in streptozotocin(STZ)-induced diabetic rats. In this study we examined the effect of troglitazone, an anti-diabetic thiazolidinedione, on diabetic neuropathy, since it also is a free-radical scavenger and a TNF-alpha inhibitor. Rats were fed powder chow mixed with troglitazone at 0.5% and 0.125% ad libitum. Although blood glucose concentrations were remarkably higher and body weight lower in diabetic than in nondiabetic rats, troglitazone had no effect on these throughout the 24-week experiment. Serum lipoperoxide concentrations, tibial nerve lipoperoxide content and serum TNF-alpha activity induced by lipopolysaccharide was increased in diabetic rats, but inhibited in troglitazone-treated rats. Motor nerve conduction velocity (MNCV) of the tibial nerve slowed in diabetic rats, compared with that in nondiabetic rats. On the other hand, the slowed MNCV was (p < 0.05-0.01) inhibited after weeks 12 and 16 of the experiment in diabetic rats treated with high and low doses of troglitazone, respectively. Morphometric analysis showed that troglitazone suppressed the decrease of the myelinated fibre area (p < 0.05), axon/myelin ratio (p < 0.01) and fascicular area (p < 0.05) and suppressed the increase of myelinated fibre density (p < 0.001) in diabetic rats. These results indicate that troglitazone has a beneficial effect on peripheral neuropathy in STZ-induced diabetic rats irrespective of blood glucose concentrations.

Animals↗
PubMed1998

Telomere shortening in the colonic mucosa of patients with ulcerative colitis.

Telomere length in human somatic cells gradually decreases with the number of cell divisions and is regarded as a marker of somatic cell turnover. Mucosal cells of the affected colon show rapid turnover in individuals with active ulcerative colitis (UC). Telomere length was determined by Southern blot analysis of terminal restriction fragments (TRFs) from the colonic mucosa of 17 patients with UC in remission, two of whom showed dysplasia, and 17 control subjects without colitis. For each individual, mean TRF length was compared between rectal mucosa and unaffected cecal mucosa. The mean TRF length of the rectal mucosa was significantly less than that of cecal mucosa in UC patients (7.87 +/- 0.36kb versus 8.77 +/- 0.21 kb; P = 0.0015, Wilcoxon signed rank test), whereas no significant difference was detected in the control subjects. The extent of telomere shortening was 10.6 +/- 3.35% in UC patients, compared with 0.8 +/- 0.64% in noncolitis controls (P = 0.0024, Mann-Whitney U-test). Four UC patients, two of whom had dysplasia, showed telomere shortening of more than 20% in the rectal mucosa. These observations suggest that telomere shortening in the colonic mucosa of individuals with UC may represent the history of mucosal inflammation during disease of long duration, and that it may contribute to aneuploidy in UC.

Adolescent↗
PubMed1998

Profiles of cytokines produced by CD4-positive T lymphocytes stimulated by anti-CD3 antibody in patients with chronic hepatitis C.

Helper T cells (Th) are classified as type 1 (Th1) and type 2 (Th2) according to the cytokines they produce; interferon-gamma is produced by Th1, and interleukin-4 by Th2. We counted the circulating CD4-positive Th cells that produce interferon-gamma or interleukin-4 with an enzyme-linked immunospot assay. CD4-positive T cells isolated from patients with chronic hepatitis B (n = 10), chronic hepatitis C (n = 16), and healthy subjects (n = 10) were stimulated with anti-CD3 antibody in vitro. The number of interferon-gamma-producing Th cells was significantly lower in patients with chronic hepatitis C than in healthy subjects (P = 0.0024), whereas in patients with chronic hepatitis B, the number was similar to that in healthy subjects (P = 0.8530). The number of interleukin-4-producing Th cells was significantly higher in patients with chronic hepatitis C (P = 0.0010) and chronic hepatitis B (P = 0.0089) than in healthy subjects. In chronic hepatitis C, the number of interferon-gamma-producing Th cells was increased after incubation of the cells with interferon-alpha (P = 0.008) or with recombinant interferon-gammala (P = 0.024), but not with interferon-beta (P = 0.051). The number of interleukin-4-producing Th cells was decreased after incubation with interferon-alpha (P = 0.0004), with interferon-beta (P = 0.003), and with recombinant interferon-gammala (P = 0.0004). Changes in the numbers of interferon-gamma- or interleukin-4-producing Th cells in vitro were more evident in sustained responders to interferon therapy than in non-responders. These results suggest that Th2 cells are the predominant cell type in chronic hepatitis C, and that their activity may be suppressed by the administration of interferon.

Adult↗
PubMed1998

Duodenal gastrinoma--clinical features and usefulness of selective arterial secretin injection test.

Duodenal gastrinoma is recognized as a relatively common cause of Zollinger-Ellison syndrome, but its clinical and biological features are not well known. Here we report a case of duodenal gastrinoma with lymph node metastasis which was confirmed by pathology examinations. Hypergastrinemia and gastric acid hypersecretion were documented, but the secretin test showed negative results. An enlarged peripancreatic lymph node lying close to the pancreas head was the only positive finding on preoperative imaging studies. The results of the selective arterial secretin injection (SASI) test suggested that the primary tumor was located in the gastrinoma triangle. Finally, surgical exploration was carried out and a submucosal tumor, approximately 15 mm in size, was detected by intraoperative palpation at the posterior wall of the proximal portion of the duodenum. Intraoperative pathology examination demonstrated metastases to regional lymph nodes. The present case calls attention to the unique features of duodenal gastrinomas, which differ from those of pancreatic origin: a highly malignant potential for its small size, and submucosal location in the proximal duodenum. The SASI test is recommended for assessing the location of a primary lesion if it cannot be identified by various conventional imaging studies.

Diagnosis, Differential↗
PubMed1998

Endogenous glucocorticoids decrease the acinar cell sensitivity to apoptosis during cerulein pancreatitis in rats.

BACKGROUND & AIMS: We recently showed that activation of the hypothalamus-pituitary-adrenal axis may mitigate the progress of acute pancreatitis. To clarify the mechanism, the role of endogenous glucocorticoids in pancreatic acinar cell death was examined. METHODS: The occurrence of apoptosis was studied in adrenalectomized or sham-operated rats with or without cerulein-induced pancreatitis. The effects of RU38486, a glucocorticoid-receptor antagonist, on the survival of cultured acinar cells (AR42J) were also examined. RESULTS: Adrenalectomy caused increases in terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL) of acinar nuclei depending on the time after adrenalectomy but not of other cell types in the pancreas and in other digestive organs. Electron microscopy showed the characteristic features of apoptosis in the TUNEL-labeled acinar cells. In cerulein pancreatitis of adrenalectomized rats, the TUNEL-labeled acinar nuclei increased remarkably depending on the time after cerulein infusion. Replacement of glucocorticoids blocked the occurrence of apoptosis in these experiments. RU38486 induced dose dependently the apoptosis of AR42J cells. CONCLUSIONS: These results provide evidence that endogenous glucocorticoids are an important factor for acinar cell survival. Endogenous glucocorticoids may protect acinar cells by decreasing their sensitivity to the induction of cell death during acute pancreatitis.

Acute Disease↗