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T Toyota

Publications and source records attributed to T Toyota.

At least 181 records · Page 10Linked to original sources

Lipopolysaccharide induces manganese superoxide dismutase in the rat pancreas: its role in caerulein pancreatitis.

Intraperitoneal injection of lipopolysaccharide (LPS) at a dose of 50 micrograms/kg increased the activity and the mRNA level of manganese superoxide dismutase (Mn-SOD) but did not change those of copper/zinc-SOD (Cu/Zn-SOD) in the rat pancreas. Both the formation of pancreatic edema and the elevation of serum amylase during caerulein pancreatitis were significantly relieved in the rats pretreated with LPS (50 micrograms/kg) compared with the rats without the pretreatment. These results support the view that superoxides play a key role in the pathogenesis of caerulein pancreatitis, and that Mn-SOD in the pancreas may work as a defense against the development of this disease.

Animals↗

Prevalence of precore-defective mutant of hepatitis B virus in HBV carriers.

Two hundred and seventy-three serum specimens from hepatitis B virus (HBV) carriers were examined for the presence of a characteristic one point mutation at nucleotide (nt) 1896 from the EcoRI site of the HBV genome in the precore region (the preC mutant) using restriction fragment length polymorphism (RFLP) analysis. This assay approach could detect preC mutants or wild-type sequences when either form constituted more than 10% of the total sample. Overall, 65.5% (76/116) of HBeAg-positive carriers had only the preC wild-type. All HBeAg-positive asymptomatic carriers (n = 14) had only the preC wild-type. In patients with chronic hepatitis B and in anti-HBe-positive asymptomatic carriers, increased prevalence of the preC mutant was associated with the development of anti-HBe antibodies and normalization of the serum alanine aminotransferase concentration. Furthermore, 27 (29.0%) of 93 HBeAg-negative carriers had unexpectedly preC wild-type sequences only. Direct sequencing of the HBV precore region of HBV specimens from 24 patients revealed no mutation at nt 1896, supporting the specificity of the RFLP analysis. These results suggest that RFLP analysis was accurate for the detection of the preC mutation and that the absence of serum HBeAg cannot be explained solely by the dominance of the preC mutant.

Base Sequence↗

Effects of cisapride on gallbladder emptying and pancreatic polypeptide and cholecystokinin release in humans.

We investigated the effects of cisapride on gallbladder motility and on the release of pancreatic polypeptide and cholecystokinin in the fasting and postprandial states. Cisapride (7.5 mg) and/or a test meal was administered intraduodenally to seven healthy volunteers with or without atropine pretreatment (0.5 mg, i.m.). In the fasting state, cisapride increased gallbladder volume to 154% of the basal level, and significantly elevated plasma pancreatic polypeptide levels. The effects of cisapride were inhibited by atropine. In the postprandial state, integrated pancreatic polypeptide and cholecystokinin responses were increased by cisapride to 180% and 192%, respectively, of control values. Atropine inhibited the integrated gallbladder and pancreatic polypeptide response to about 60% of the control value, but did not affect the cholecystokinin response. These observations suggest that: (1) fasting gallbladder tone is influenced by cholinergic inhibitory mechanisms, (2) acetylcholine (ACh) is the final mediator for about 40% of the postprandial gallbladder emptying and pancreatic polypeptide response, and (3) coordination between the ACh-independent cholecystokinin response and ACh-dependent pancreatic polypeptide response may be important in the regulation of postprandial gallbladder emptying.

Adult↗

Nitric oxide modulates pancreatic edema formation in rat caerulein-induced pancreatitis.

This study was designed to investigate the role of nitric oxide (NO) in the formation of pancreatic edema in caerulein-induced pancreatitis in rats. Pancreatitis was produced by two intraperitoneal injections of caerulein, and plasma amylase concentration, pancreatic edema index (pancreatic wet weight/body weight), and Evans blue extravasation (as a measure of vascular permeability) were evaluated 5 h after the first injection. Four doses (1, 2.5, 5, and 10 mg/kg) of NG-nitro-L-arginine (L-NNA), an NO synthase inhibitor, were subcutaneously administered at -0.5, 0.5, 1.5, 2.5, and 3.5 h after the first injection of caerulein. L-NNA significantly lowered the edema index, the wet/dry weight ratio of the pancreas, and Evans blue extravasation in the rats with pancreatitis. The maximal effect was obtained by L-NNA at a dose of 2.5 mg/kg; this inhibited the increase in pancreatic edema formation from the control value by 60%-70%. Intraperitoneal injections (20 mg/kg, five times) of L-arginine, a substrate for NO production, partly reversed the L-NNA-induced inhibition of pancreatic edema formation, but D-arginine, an enantiomer of L-arginine, did not show any effect. Plasma amylase concentrations were not significantly affected by any dose of L-NNA, nor were they affected by L- or D-arginine. These findings strongly suggest that endogenous NO plays an important role in the formation of pancreatic edema in caerulein-induced pancreatitis in rats, probably by increasing vascular permeability and protein extravasation.

Acute Disease↗

The role of endogenous glucocorticoids in rat experimental models of acute pancreatitis.

BACKGROUND & AIMS: Cytokines activate the hypothalamic-pituitary-adrenal axis and suppress inflammation by stimulating glucocorticoid secretion. The state of adrenocortical function during acute pancreatitis and its role in this disease were determined. METHODS: Cerulein-induced pancreatitis or closed duodenal loop pancreatitis was produced in rats that had undergone adrenalectomy or sham adrenalectomy, and the serum corticosterone and interleukin 8 levels and the intensity of the pancreatitis were examined. RESULTS: Serum corticosterone levels were significantly higher than basal levels in both models of experimental pancreatitis. In both models, adrenalectomy increased serum amylase and pancreatic edema and produced more severe inflammation. Adrenalectomy significantly increased mortality in animals with closed duodenal loop pancreatitis. Exogenous hydrocortisone administered to adrenalectomized animals suppressed the elevation of serum interleukin 8 levels and decreased both the severity of pancreatitis and mortality. CONCLUSIONS: These results suggest that the adrenocortical function is stimulated during acute pancreatitis and that the secretion of endogenous glucocorticoids may play an important role in mitigating the progress of this disease, probably by inhibiting cytokine production.

Acute Disease↗

Antibodies to GAD in Japanese diabetic patients: a multicenter study.

We determined the prevalence of antibodies to glutamic acid decarboxylase (anti-GAD) in Japanese diabetic patients. Anti-GAD were detected by RIP Anti-GAD Hoechst, which is a new sensitive radioimmunoassay (RIA) kit using purified pig brain GAD as the antigen. One thousand nine hundred Japanese patients were collected by the Study Group for Antibodies to GAD. The prevalence of anti-GAD in the subjects of this study was: 35.4% (326/921) in all patients with IDDM, 50.3% (96/191) in patients with IDDM less than 1-year duration, 4.3% (29/680) in NIDDM, 37.9% (39/103) in slowly progressive IDDM, 10.5% (4/38) in gestational diabetes mellitus, 0% (0/27) in impaired glucose tolerance, 4.8% (6/124) in the school children with glycosuria, 2.1% (1/47) in the relatives of IDDM and 5.0% (1/20) in neurological diseases without diabetes. The prevalence in normal subjects was 2.2% (7/323). Anti-GAD are frequently detected by the RIA kit in patients with IDDM of short duration and this assay may be useful for population screening for IDDM and for better understanding of its pathogenesis.

Adolescent↗

Injection of ethanolamine oleate into a segmental portal branch for pharmacologic hepatic segmentectomy in dogs.

RATIONALE AND OBJECTIVES: Currently available treatments for hepatocellular carcinoma are not satisfactory in terms of recurrence rates. In this study, we injected ethanolamine oleate (EO) into a portal branch in an attempt to cause necrosis of a liver segment in which hepatocellular carcinoma might be located. METHODS: Nine dogs received EO injections via a balloon catheter into a segmental portal branch of the liver. RESULTS: Immediately after injection, 80-100% of the liver cells in the EO-injected segment underwent coagulative necrosis. After 1 week, the EO-injected segment had become completely necrotic in two dogs. Only a few viable hepatocytes were still observed around the arteries and beneath the liver capsule in another dog. No pathologic changes were observed in the lungs, kidneys, or heart of any dog. There was a correlation between the EO dosages and the volume of the EO-injected liver tissue. CONCLUSION: EO injection into a portal branch results in the pharmacologic destruction of the corresponding liver segment. This procedure may be beneficial in the treatment of hepatic malignancies.

Animals↗

The effect of helodermin in rat dispersed pancreatic acini.

Helodermin is a 35 amino acid-residue peptide of the vasoactive intestinal polypeptide (VIP) family, which was originally isolated from the venom of Heloderma suspectum on the basis of its capacity to stimulate adenylate cyclase in the rat pancreas. In the present study, using rat dispersed pancreatic acini, we examined the binding characteristics of helodermin, its action on amylase secretion, and the production of intracellular cyclic AMP (cAMP). Helodermin stimulated intracellular cAMP production dose dependently in a manner that was nearly identical to that of VIP. Helodermin stimulated amylase secretion dose dependently, showing an efficacy similar to that of VIP but with 100 times less potency than VIP. Adding 0.5 mM 3-isobutyl-1-methylxanthine increased the potency of helodermin's action on amylase secretion but did not change the efficacy. The binding study showed that the order of binding affinity to VIP receptors was VIP = helodermin > secretin, while the order of that to secretin receptors was secretin > helodermin > VIP. These results suggest that helodermin stimulated amylase secretion from rat dispersed pancreatic acini via VIP-preferring receptors that are coupled to the production of intracellular cAMP, but a part of the postreceptor mechanism for enzyme secretion is different from that of VIP.

Amylases↗

Transient hepatic fibrin-ring granulomas in a patient with acute hepatitis A.

A case of acute hepatitis A associated with fibrin-ring granulomas in the liver is presented. Because a relationship between acute hepatitis A infection and granuloma formation had not previously been established, liver specimens were examined from both the hepatitic and recovery phases. Numerous fibrin-ring granulomas were observed in the parenchyma during the hepatitic phase. The cellular components of the granulomas were largely macrophages and CD4-positive T-cells. Granulomas had disappeared completely by the recovery phase. These results suggest that fibrin-ring granulomas were caused by hepatitis A virus infection. This virus may activate macrophages and CD4-positive T-cells through an as-yet undetermined mechanism.

Acute Disease↗

Gastric myoelectrical activities in elderly human subjects--surface electrogastrographic observations.

To investigate the alteration of the gastric electrical activities by aging, we performed electrogastrography (EGG) on 13 asymptomatic young human subjects under 60 years old (the young group) and 12 subjects over 60 years (the elderly group). Surface EGG was recorded at fasting state for 30 minutes in each subject. We expressed the frequency distribution of surface EGG in each subject with the median value of frequency distribution (FMED) to represent the center of the electrical activities, and the interquartile range of frequency distribution (FIQR) as the indicator of regularity. FMED in the young group was 3.0: [2.9, 3.4] (median: [range]) cycles per minute (cpm), while it was 3.3: [3.0, 4.0] in the elderly group which showed statistically a significant difference between the groups (p = 0.01). FIQR in the young group was 0.5: [0.1, 1.8] and that in the elderly group was 0.55: [0.4, 1.7], which was not significantly different statistically. These data showed that aging increases the frequencies of the rhythm of surface EGG, without disturbing its regularity. This change may be a part of a spectrum of physiological changes accompanied with aging, and are unlikely to have clinico-pathological significance.

Adult↗

Altered leukotriene B4 metabolism in colonic mucosa with inflammatory bowel disease.

BACKGROUND: omega-Oxidation is regarded as the major pathway for leukotriene B4 (LTB4) metabolism. Very little is known about it in colonic mucosa with inflammatory bowel disease (IBD). METHODS: We investigated the metabolic ratio of omega-oxidation to LTB4 biosynthesis in colonic mucosa from patients with IBD and control subjects. After incubation of colonic mucosa with 14C-arachidonic acid and ionophore A23187, we separated LTB4 and its omega-oxidative metabolites by high-performance liquid chromatography. RESULTS: The rate of LTB4 omega-oxidation was comparable to the rate of its biosynthesis. The metabolic ratio was significantly decreased in inflamed mucosa with ulcerative colitis. CONCLUSIONS: LTB4 omega-hydroxylase activity is an important factor in regulating LTB4 level in colonic mucosa, and the increased LTB4 level in inflamed mucosa with IBD, especially ulcerative colitis, is caused by decreased LTB4 omega-hydroxylase activity and increased 5-lipoxygenase activity.

Adolescent↗

Clinical evaluation of lansoprazole in the treatment of peptic ulcers: initial healing and prevention of relapse. Tohoku Peptic Ulcer Study Group.

The clinical usefulness of lansoprazole in the healing of gastric and duodenal ulcers, the S2-stage shift rate (white scarring rate), and endoscopic healing rate with respect to degree of gastric mucosal atrophy were investigated. The subjects were 50 gastric ulcer and 37 duodenal ulcer patients. The endoscopic healing rate in patients with gastric ulcers after initial treatment with lansoprazole was 92% after 8 weeks. The S2-shift rate was 38% after 8 weeks. The 8-week healing rate in patients without atrophy was 100% and with atrophy was 92%, although the difference was not statistically significant. The S2-shift rate in patients without atrophy was 42% and in patients with atrophy was slightly lower, at 37%, although the difference was not statistically significant. The endoscopic healing rate in patients with duodenal ulcers was 93% after 6 weeks, and the S2-shift rate was 59%. It is firmly established that atrophic gastric mucosa shows a reduction in mucosal defense factors. However, lansoprazole achieved good endoscopic healing rates and S2-shift rates even in patients with gastric ulcers with atrophic background mucosa.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Confluent monolayers of bile duct epithelial cells with tight junctions.

The culture of fully differentiated intrahepatic bile duct epithelial cells (IBDECs) to use as a model for the in vivo intrahepatic biliary tract has not been established. IBDECs from normal rat livers were grown on a collagen-coated permeable filter and formed a confluent monolayer 7 days after being plated. Positive reactions for cytokeratin-19 and retained gamma-glutamyl transpeptidase (GGTP) activity were shown. The transepithelial electrical resistance between the apical and the basolateral compartment culture chambers increased with the culture age and plateaued after the 7th day. The resulting cultured cells displayed a number of characteristics. (1) The cells formed a thin, continuous monolayer and displayed microvilli on the apical surface and junctional complexes between the cells, consistent with in vivo IBDECs. (2) Cells cultured for more than 7 days prevented the passage of horseradish peroxidase (HRP) and ruthenium red through paracellular pathways. (3) Seven-day-old cultures displayed a mean transepithelial electrical resistance of 137.3 omega-cm2, which decreased by 27.1% from its initial level after cell treatment with ethylenediamineteraacetic acid (EDTA). These results indicate that confluent IBDEC monolayers are well differentiated and polarized with tight junctions (TJs) between the cells. These cell monolayers can provide a useful and relevant model for the in vitro study of various in vivo bile duct phenomena.

Animals↗

[A case of Kasabach-Merrit syndrome complicated with DIC treated effectively by long term oral administration of warfarin].

A 20 year-old female patient with Kasabach-Merrit syndrome, suffered from chronic consumption coagulopathy due to localized intravascular coagulation in the tumors. She had been diagnosed as Kasabach-Merrit syndrome immediately after birth and below knee amputation of her right lower leg was performed at the age of 2 years because of her giant hemangioma on the right foot and lower leg. After the operation, she had often complained of severe pain and enlargement of the residual tumors due to continuous thrombus formation within the tumors. She was admitted to the third Department of Tohoku University Hospital in order to initiate oral anticoagulant therapy with Warfarin at the age of 12 years. After the administration of 2.5 mg/day Warfarin, she has maintained good clinical condition until now, despite the occasional occurrence of coagulation abnormalities. We believe that the results of this case indicate the efficacy of oral anticoagulant therapy in the treatment of chronic consumption coagulopathies complicated with other diseases.

Administration, Oral↗

Enhanced interferon-gamma production and B7-2 expression in isolated intestinal mononuclear cells from patients with Crohn's disease.

Many of the in vivo activities of interferon (IFN)-gamma match the changes found in inflammatory bowel disease, but its importance is controversial. Interferon (IFN)-gamma induces the expression of B7-2 costimulatory molecules on monocytes. We measured levels of IFN-gamma production in intestinal mucosa and isolated lamina propria mononuclear cells (LPMC) in patients with Crohn's disease (CD) and ulcerative colitis (UC). We also investigated the induction of B7-2 on the LPMC by flow cytometry. Mucosal IFN-gamma production was higher than the control level in patients with CD, but this was not the case in UC. IFN-gamma production and B7-2 expression in the LPMC of CD were higher than in the LPMC of UC and controls, and high levels of B7-2 expression were observed on the LPMC of CD after incubation with endotoxin. The induction of B7-2 on the LPMC of CD may provide a mechanism for the amplification of T cell proliferation and lymphokine production by IFN-gamma-activated LPMC.

Adult↗