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S Inoue

Publications and source records attributed to S Inoue.

At least 847 records · Page 47Linked to original sources
PubMed1993

Glycine sensor in the hepato-portal system and their reflex effects on pancreatic efferents in the rat.

We earlier reported the existence of vagal arginine, alanine, and leucine sensors in the liver which modulate amino acid-induced pancreatic hormone secretion. To determine the possible existence of glycine sensors in the liver and their reflex effects, afferent discharges from the hepatic branch and efferent discharges from the pancreatic branch of the vagus nerve were recorded. Intraportal administration of 0.1, 1, and 10 mM of L-glycine solution (0.1 ml) depressed the afferent discharge rate of the hepatic branch of the nerve in a dose-dependent manner, and increased the efferent discharge rate of the pancreatic vagal branch. The results suggest the existence of glycine sensors in the hepato-portal system that exert reflex regulation on the pancreatic vagus nerve activity.

Animals↗
PubMed1993

Cryofixation of basement membranes followed by freeze substitution or freeze drying demonstrates that they are composed of a tridimensional network of irregular cords.

Since conventional chemical fixation may extract tissue components and thus alter structural organization, cryofixation was used to reexamine the ultrastructure of three thick basement membranes: lens capsule, Reichert's membrane, and Engelbreth-Holm-Swarm (EHS) tumor matrix, and two thin basement membranes, those of epididymis and semi-niferous tubules. Cryofixation was achieved by slam freezing followed by either freeze substitution in dry acetone containing 1% osmium tetroxide and 0.05% uranyl acetate or freeze drying in a molecular distillation dryer. The results by both procedures demonstrate that thick basement membranes and the lamina densa of thin basement membranes are composed of a network of anastomosing strands referred to as cords. The cords vary in density and distinctiveness, but their thickness averages 3 to 5 nm in every tissue examined. The spaces separating the cords vary within wide limits, but their mean diameter is approximately 15 nm in every case. Two other common features are 1) the presence within the network of a few 1.5-3.0-nm-thick filaments and 2) 4.5-nm-wide sets of parallel lines referred to as double tracks. When these results are compared with those previously described after conventional fixation, no significant difference is observed in either the cord network or the associated filaments and "double tracks." However, in the thin basement membranes processed by cryofixation, the lamina densa is in direct contact with epithelial cells, whereas, after conventional fixation, the lamina densa is separated from the epithelial cells by a pale layer referred to as lamina lucida or lamina rara. Immunogold labeling of three basement membranes after cryofixation and freeze substitution in acetone containing 0.3% glutaraldehyde yields strong reactions for laminin, type IV collagen, and heparan sulfate proteoglycan. Comparison with previous results indicates that conventional formaldehyde fixation adequately preserves laminin and type IV collagen but causes the loss of some proteoglycan. It is concluded that, except for this loss and the absence of lamina lucida in cryofixed thin basement membranes, the morphological and antigenic features obtained after cryofixation are similar to those observed in the past after conventional fixation.

Animals↗
PubMed1993

Immunohistochemical detection and northern blot analysis of estrogen receptor in osteoblastic cells.

Expression of estrogen receptor (ER) was studied in MC3T3-E1 cells (mouse osteoblastic cell line), HOS TE85 cells (human osteosarcoma cell line), and primary osteoblastic cells derived from mouse calvaria with immunohistochemical techniques. The staining of ER was readily detectable in MC3T3-E1 cells, HOS TE85 cells, and primary osteoblastic cells by using a monoclonal anti-ER antibody that recognizes the DNA binding domain of ER. The immunoreactivity was distributed in the cytoplasm as well as in the nuclei. 17 beta-Estradiol (10(-8) M) did not alter this staining pattern. The expression of ER was confirmed by Northern blot analysis using rat ER cDNA probe, which revealed a 6.5 kb band in MC3T3-E1 cells and a 6.2 kb band in HOS TE85 cells. The mRNA level of ER was not altered by 17 beta-estradiol (10(-8) M). The immunohistochemical studies showed that ER was not detectable in all cells but in a small population of each cell type. This study is the first report to demonstrate the presence of ER immunohistochemically, and our results suggest the heterogeneity of ER expression among osteoblastic cells.

3T3 Cells↗
PubMed1993

Mutations of the p53 tumor suppressor gene and the ras gene family in intrahepatic cholangiocellular carcinomas in Japan and Thailand.

The incidence and pattern of mutations of the ras oncogenes and the p53 tumor suppressor gene have been shown to differ among different cancer types and even among the same cancer types with different etiological backgrounds. For example, in a previous study we showed that not only the etiology but also the incidence of point mutation of the c-Ki-ras oncogene in cholangiocellular carcinomas (CCCs) differ between Japanese and Thai patients. In the study presented here, we examined the incidence of mutations in the ras gene family and the p53 gene in CCCs of both Japanese and Thai patients by single-strand conformation polymorphism and direct sequencing analyses and compared the pattern of p53 mutation between these two CCC groups. Although the incidence of ras mutation differed markedly between Japanese (seven of 12, 58%) and Thai (two of 26, 8%) cases, the incidence of p53 mutation was similar: four of 12 (33%) and nine of 26 (35%), respectively. Except for one case in which deletion-insertion was detected in the second exon of the N-ras gene, all ras mutations occurred at codon 12 or 13 of the c-Ki-ras gene. All p53 mutations but one were detected in a highly conserved region, and the predominant form of the mutations was G:C-->A:T transition at CpG sites in both Japanese and Thai cases, similar to that reported for colorectal cancers. Therefore, in contrast to the ras oncogenes, mutation of the p53 gene was frequently involved in the development of CCCs in both Japanese and Thai patients, irrespective of any difference in etiology.

Adult↗
PubMed1993

Depressive states in workers using computers.

There have been few reports investigating the depressive states in workers using computers. We describe the depressive states observed in workers using computers and discuss the sources of their occupational stresses. The first subject is a 34-year-old male manager of a manufacturing company who had customarily worked until 9 PM. In 1985, it become necessary for him to work until midnight; symptoms of depression began to appear during this period, exacerbated after trouble with a computer. In 1986, he visited a psychiatrist and his condition was diagnosed as Major Depression according to DSM-III. The second subject is a 26-year-old male VDT (visual display terminal) operator in a general hospital. Before the onset, he had had to work until 8 PM and, at the end of each month, until midnight. Two months later, he became depressed and his condition was diagnosed as Major Depression according to DSM-III. The third subject is a 32-year-old male chief in the computer programming section of a bank. He had had to work until 8 PM, became depressed, and visited a psychiatrist who diagnosed his condition as Major Depression according to DSM-III. The authors discuss these cases from the standpoint of occupational stresses, as they are associated with work overload, and the important role these stresses played in the onset of the workers' depressive states.

Adult↗
PubMed1993

An evaluation of the effects of cytokines on intracellular oxidative production in normal neutrophils by flow cytometry.

To evaluate the effects of inflammatory cytokines on oxidative production in normal neutrophils, seven kinds of cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), interleukin-2 (IL-2), IL-6, IL-1 alpha, IL-1 beta, and interferon-beta (IFN-beta) were tested. The intracellular hydrogen peroxide (H2O2) in individual cells was determined by flow cytometry. According to the levels of intracellular H2O2 enhanced by cytokines, these seven cytokines were classified into three types: (1) prominently effective--GM-CSF; (2) moderately effective--G-CSF, IL-6, and IL-2; (3) weakly or ineffective--IFN-beta, IL-1 alpha, and IL-1 beta. Changes in cell size and cell surface structure after stimulation of those seven cytokines were simultaneously measured by flow cytometry. The most prominently effective cytokine, GM-CSF, initially caused enlargement of cell size and irregularity of the cell surface and subsequently increased H2O2 production by neutrophils. In contrast, the weakly or ineffective cytokines, like IL-1 beta, had no effects on cell size or cell surface. Our study indicates that some kinds of cytokines enhance oxidative production and cause morphological changes in neutrophils.

Cell Membrane↗
PubMed1993

The basement membranes of cryofixed or aldehyde-fixed, freeze-substituted tissues are composed of a lamina densa and do not contain a lamina lucida.

When tissues are processed for electron microscopy by conventional methods, such as glutaraldehyde fixation followed by rapid dehydration in acetone, basement membranes show two main layers: the electron-lucent "lamina lucida". (or rara) and the electron-dense "lamina densa". In an attempt to determine whether this subdivision is real or artefactual, two approaches have been used. Firstly, rat and mouse seminiferous tubules, mouse epididymis and associated tissues, and anterior parts of mouse eyes were subjected to cryofixation by instant freezing followed by freeze substitution in a -80 degrees C solution of osmium tetroxide in dry acetone, which was gradually warmed to room temperature over a 3-day period. The results indicate that, in areas devoid of ice crystals, basement membranes consist of a lamina densa in direct contact with the plasmalemma of the associated cells without an intervening lamina lucida. Secondly, a series of tissues from mice perfused with 3% glutaraldehyde were cryoprotected in 30% glycerol, frozen in Freon 22 and subjected to a 3-day freeze substitution in osmium tetroxide-acetone as above. Under these conditions, no lamina lucida accompanies the lamina densa in the basement membranes of the majority of tissues, including kidney, thyroid gland, smooth and skeletal muscle, ciliary body, seminiferous tubules, epididymis and capillary endothelium. Thus, even though these tissues have been fixed in glutaraldehyde, no lamina lucida appears when they are slowly dehydrated by freeze substitution. It is concluded that the occurrence of this lamina in conventionally processed tissues is not due to fixation but to the rapid dehydration. However, in this series of experiments, the basement membranes of trachea and plantar epidermis include a lamina lucida along their entire length, while those of esophagus and vas deferens may or may not include a lamina lucida. To find out if the lamina lucida appearing under these conditions is a real structure or an artefact, the trachea and epidermis were fixed in paraformaldehyde and slowly dehydrated by freeze substitution. Under these conditions, no lamina lucida was found. Since this result is the same as observed in other tissues by the previous approaches, it is proposed that the lamina lucida is an artefact in these as in the other investigated basement membranes. Thus, basement membranes are simply composed of a lamina densa that closely follows the plasmalemma of the associated cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1993

Survival and recurrence after low anterior resection and abdominoperineal resection for rectal cancer: the results of a long-term study with a review of the literature.

Morbidity, survival, and recurrence in 203 patients treated with curative low anterior resection (LAR) were compared with those in 100 patients treated with curative abdominoperineal resection (APR). The overall 5-year survival figures for the total number of, LAR and APR patients were 75.6 +/- 5.7%, 79.8 +/- 6.4% and 67.7 +/- 9.6%, respectively. The prognosis for cancers situated low enough in the rectum to involve the anal canal was poor even when managed by APR, as evidenced by a low survival at 5 years of 59.0 +/- 9.6% and a high pelvic recurrence rate of 34%. For all except these tumors, LAR proved at least equal to, or better than APR as a curative surgical method for middle and low rectal cancers, on the basis of 5-year survival being 79.8 +/- 6.4% vs 78.7 +/- 5.2%, operative mortality being 1.5% vs 1.0%, morbidity being 39.4% vs 59.0%, and the incidence of pelvic recurrence being 8.9% vs 13.5%. When deciding upon the most appropriate surgical procedure for rectal cancer, especially for middle or low rectal lesions, the patient should not simply be condemned to a permanent colostomy. Thus, we first attempt LAR for every lesion except those which are very advanced or those with anal canal involvement, if technically feasible and suitable for the individual patient.

Adult↗
PubMed1993

Comparison of DNA synthesis in white and brown adipose tissue in rats with ventromedial hypothalamic lesions.

Ventromedial hypothalamic (VMH) lesions cause excessive fat accumulation in white adipose tissue (WAT), and brown adipose tissue (BAT); however, little information is available on whether or not cell proliferation occurs in WAT and BAT after VMH lesioning. In this study, we determined the DNA content and thymidine incorporation in unilateral parametrial WAT and interscapular BAT 0, 1, 3, and 7 days after VMH lesioning, and examined the mechanism of increased DNA content in WAT. In rats with VMH lesions, the weight of WAT and BAT had increased significantly at 7 days, and the DNA content and thymidine incorporation of WAT had increased significantly at 3 days and continued to increase for up to 7 days, while those of BAT did not increase for as long as 7 days after VMH lesioning. Restricted food intake according to the pair-feeding method partially inhibited the increased DNA content in WAT. The increased DNA content in WAT was mostly restored but not completely by the administration of anti-insulin antibody, and by administration of propranolol, a beta-adrenergic blocker. The results demonstrated that VMH lesions induced DNA synthesis in WAT early after VMH lesioning, but did not induce DNA synthesis in BAT, and suggested that either hyperinsulinemia or a beta-adrenergic receptor mechanism or both may be responsible for the increased DNA content in WAT.

Adipose Tissue↗
PubMed1993

Estrogen and bone.

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Base Sequence↗
PubMed1993

Elevated serum thymidine kinase activity in patients with acute viral hepatitis.

To evaluate the clinical applications of serum thymidine kinase (TK) activity, we compared the results obtained with this parameter with those of other liver function tests in 27 patients with acute viral hepatitis and 16 normal controls. In those in the acute stage, the serum TK activity increased significantly to 55.5 +/- 66.5 U/L. There was no significant correlation between serum TK activity and findings for serum albumin, bilirubin, alkaline phosphatase or r-glutamyl transpeptidase. However, it did correlate significantly well with the serum activity of aspartate aminotransferase (AST) (r = 0.621, P < 0.01), alanine aminotransferase (ALT) (r = 0.551, P < 0.01), and lactate dehydrogenase (LDH) (r = 0.620, P < 0.01). Serum TK activity reached higher than 70 U/L in 8 of 11 patients with hepatitis A; however, no patients with the other types of hepatitis reached such a high level. During the recovery stage, the serum TK activity decreased significantly to 5.9 +/- 1.7 U/L (P < 0.01), and did not correlate with AST, ALT, LDH or other conventional liver function parameters. The data suggest that an elevation of serum TK in patients with acute viral hepatitis results from hepatocellular damage. A marked elevation of serum TK activity may thus provide a marker for acute hepatitis A infection.

Acute Disease↗
PubMed1993

A case of perianal Paget's disease associated with a sigmoid colon carcinoma.

A case of perianal invasive Paget's disease associated with a sigmoid colon carcinoma is presented. The chief complaint was perianal irritation for a year. Histologic examination yielded a correct diagnosis and abdominosacral resection with wide excision of the cutaneous component was performed. Histology of the resected specimen revealed the Paget's disease to be invasive of the dermis, the sigmoid colon carcinoma to be in Dukes' A stage and the two lesions to be different. The patient has been disease-free for more than 5 years after the operation.

Adenocarcinoma↗
PubMed1993

Ventromedial hypothalamic lesions increase gastrointestinal DNA synthesis through vagus nerve in rats.

BACKGROUND: It was recently reported that ventromedial hypothalamic (VMH) lesions produced an increase in gastrointestinal DNA content in rats. In the present study, the mechanism of this alteration was examined. METHODS: The DNA content and synthesis after VMH lesioning in rat gastrointestinal tracts were determined. RESULTS: Total content of DNA in stomach and small intestine began to increase at 3 days and continued to increase for 7 days, whereas DNA content in the large intestine began to increase at 3 days and maintained the same level until 7 days after VMH lesioning. DNA synthesis of these organs increased and reached maximum at 3 days and then decreased to the initial level 7 days following the lesions. This increase in DNA content and synthesis in these organs was largely inhibited by bilateral subdiaphragmatic vagotomy or the administration of atropine, a cholinergic blocker, but not by the administration of anti-insulin antibody. CONCLUSIONS: VMH lesions induce cell proliferation in the rat gastrointestinal tract by the firing of vagus nerve activity mainly through the cholinergic receptor mechanism.

Animals↗
PubMed1993

Hepatic glucose-sensitive unit regulation of glucose-induced insulin secretion in rats.

Vagal glucose receptors, or glucose-sensitive units which modulate insulin secretion, exist in the liver. This study sought to determine the pathway of portal glucose-sensitive unit-regulated insulin secretion by measuring plasma insulin after intraperitoneal (IP) injection of glucose under unanesthetized and unrestrained conditions (Experiment 1), and by recording electrical discharge after intraportal injection of glucose (Experiment 2) in rats with hepatic and/or celiac vagotomy. In Experiment 1, plasma insulin was significantly reduced and plasma glucose elevated after IP glucose injection (1 g/kg) in the three groups of hepatic-, celiac-, and hepatic- and celiac-vagotomized rats in comparison with a sham-vagotomized group. There were no significant differences among the four groups in plasma insulin or glucose after IV glucose injection (0.5 g/kg). In Experiment 2, intraportal injection of 400 mg/dl of glucose solution, a similar concentration to that produced by 1 g/kg of IP glucose injection, caused a reduction in the discharge rate of hepatic vagal afferents and an increase in that of pancreatic vagal efferents. This increase was blocked by prior sectioning of the hepatic branch of the vagus nerve. These results suggested that hepatic glucose-sensitive units enhanced glucose-induced insulin secretion via the hepatic vagal afferents and the pancreatic vagal efferents mediated by the brain stem center in vivo. The physiological role of these hepatic glucose-sensitive units is assumed to maintain blood glucose homeostasis by enhancing glucose-induced insulin secretion.

Afferent Pathways↗
PubMed1993

Modulation of insulin secretion by hepatic vagotomy in cirrhotic rats.

There is evidence that glucose sensors and arginine sensors are present in the hepato-portal system and exert a reflex regulation of the pancreatic neuroendocrine system in normal rats. To investigate the function of these sensor systems in liver cirrhosis, we examined the effect of hepatic vagotomy on plasma glucose and insulin concentrations after intraperitoneal (IP) injection of glucose or L-arginine in carbon tetrachloride (CCl4)-induced cirrhotic rats. After IP glucose injection, hepatic vagotomy decreased plasma insulin with elevation of plasma glucose in control rats; however, in cirrhotic rats, this procedure did not affect either plasma glucose or insulin concentrations. After IP arginine injection, hepatic vagotomy increased plasma insulin and reduced plasma glucose in control rats, although in cirrhotic rats, this procedure did not affect plasma glucose but did increase plasma insulin concentrations. These results suggest that function of the glucose sensor in CCl4-induced cirrhotic rats is disturbed, although that of the arginine sensor is retained.

Afferent Pathways↗
PubMed1993

Hypergastric acid secretion in rats with ventromedial hypothalamic lesions.

This study was designed to investigate abnormal gastric acid secretion in ventromedial hypothalamic (VMH)-lesioned rats. Basal secretion and secretion stimulated by pentagastrin (25 micrograms/kg, IP) or histamine (2 mg/kg/h, IV) were significantly higher in VMH-lesioned rats than in sham VMH-lesioned rats. Subdiaphragmatic vagotomy and methyl atropine treatment (5 mg/kg, IV) remarkably decreased both basal (about 36-44%) and stimulated secretion (about 36-67%) in VMH-lesioned rats, but did not completely reverse it to normal. Serum insulin and glucose levels were significantly higher in VMH-lesioned rats, but serum gastrin levels were not. VMH-lesioned rats showed significantly heavier gastric dry weight; however, no difference in the mucosal layer/total layer ratio of the gastric wall and the density of the parietal cells was observed between the two groups, indicating that the total number of parietal cells might have increased in VMH-lesioned rats because the increase of gastric dry weight can be presumed to be due to increase of the gastric mucosal layer as well as total layer. These results suggest that vagal activation is one of the main contributors to hypergastric acid secretion in VMH-lesioned rats, but that other factors such as increase of parietal oxyntic cell number may also contribute.

Animals↗
PubMed1993

Protein chemotaxonomy of genus Datura: identical amino acid sequence of ferredoxin from two varieties of Datura stramonium.

The complete amino acid sequence of the respective [2Fe-2S] ferredoxins from two varieties of Datura stramonium, D. stramonium var. stramonium and D. stramonium var. tatula, have been determined by automated Edman degradation of the entire Cm-protein and of the peptides obtained by tryptic digestion and CNBr treatment. The ferredoxins from the two plants exhibited identical amino acid sequences, suggesting a very close taxonomic relationship between the two. This result supports the proposal by Blakeslee and others that these plants, at first named by Linnaeus as two distinct species, i.e. D. stramonium L. and D. tatula L., should be considered two varieties of a single species.

Amino Acid Sequence↗