Biomedical subjects

S Kawano

Publications and source records attributed to S Kawano.

At least 217 records · Page 12Linked to original sources

PubMed1995

Gastric blood flow in ulcer diseases.

BACKGROUND: Gastric blood circulation maintains the structure and functions of the stomach, and thereby is closely associated with the pathogenesis and the healing of gastrointestinal lesions. Gastric mucosal blood flow, regulated by systemic neural and humoral factors, is also modified by local metabolic factors such as prostaglandins, leukotrienes. PAF and other endogenous chemical mediators in mucosa. Endothelium-derived factors that are produced by vascular endothelial cells, inducing relaxation or contraction of the blood vessels, are also recognized as basic mediators that regulate the circulation in the stomach. RESULTS: The regionally disturbed gastric circulation in combination with the presence of acid is closely associated with the pathogenesis of NSAIDs and ethanol-induced gastric lesions. Blood flow and oxygenation in the surface mucosa surrounding the peptic ulcer change during healing, depending on the quality of the ulcer healing process: an increased blood circulation with increased oxygen supply to the ulcer margin is important for rapid ulcer healing shown by reflectance spectrophotometry. Factors altering the blood flow during the ulcer healing are discussed.

Animals↗

PubMed1995

Catecholamine response to stress: age related modifications in tail-suspended rats.

The catecholamine response to acute stress has been shown to change with age. However, alterations under chronic stress conditions have not been established. This study attempted to determine whether aging modifies the catecholamine response to chronic stress load in rats subjected to tail suspension. Urinary excretions of epinephrine (E) and norepinephrine (NE) were monitored before and during the tail suspension experiments in rats at two different ages: 5 weeks old (young) and 18 months old (aged). Basal excretions of E and NE before the suspension were higher in the aged rats, indicating that sympathetic-adrenal medullary activities increase with age under resting conditions. The chronic stress load elicited E responses in the aged rats similar to those in the young rats. The NE responses, however, were completely different in that tail suspension caused a greater increase in NE excretion in the young rats than in the aged rats. This finding suggests that the sympathetic response to chronic stress load changes with age.

Adrenal Glands↗

PubMed1995

Changes in prevalence of anti-HCV antibodies associated with preventive measures among hemodialysis patients and dialysis staff.

The latest prevalence of hepatitis C virus (HCV) infection was evaluated in 548 Japanese patients undergoing hemodialysis, and 216 members of the hospital dialysis staff. An assay of anti-HCV antibodies was performed using both first- and second-generation immunoenzymatic tests, and anti-HCV specificity was confirmed with a second-generation recombinant immunoblot assay. Of 548 hemodialysis patients, 90 (16.4%) were positive with first-generation, and 166 (30.3%) with second-generation tests. These rates were significantly higher than those for either hospital staff members (0.5% and 2.3%; p < 0.01) or healthy blood donors (0.98% and 1.30%; p < 0.001). Patients with a history of blood transfusion tended to have a higher positivity rate for anti-HCV than did the non-transfused group (35.4% vs. 25.7% with second generation tests; p < 0.05). Positivity for anti-HCV was related to the duration of hemodialysis. Only a few patients seroconverted during the 2-year, 5-month period between the previous and present studies. Although hemodialysis patients remain a high-risk group for HCV infection, the prevalence of anti-HCV antibodies has decreased recently thanks to the use of erythropoietin for renal anemia, the universal screening of blood donors for anti-HCV antibodies, and improvements in infection control measures for this virus.

Adult↗

PubMed1995

Plasma insulin and blood pressure in normotensive Japanese men with normal glucose tolerance.

OBJECTIVE: To determine whether blood pressure within the normal range is associated with plasma insulin concentration in a Japanese population with normal glucose tolerance. METHODS: We studied 491 normotensive Japanese men with normal glucose tolerance, who had never been treated with antihypertensive medications. Plasma glucose and insulin response during a 75-g oral glucose-tolerance test, blood pressure, body mass index, serum lipids, alcohol consumption and smoking status were obtained. The subjects were divided into quartiles according to mean blood pressure level (< 79, 79-84, 85-91 and > or = 92 mmHg). To eliminate possible confounding factors, analysis of covariance was also performed. RESULTS: In univariate analyses the plasma insulin response after an oral glucose load, especially after 60 min, was significantly related to blood pressure level. Plasma glucose was related to blood pressure level only at fasting. When adjusted for age, body mass index, plasma glucose response and alcohol consumption, plasma insulin concentrations after 30 and 60 min in the highest quartile were significantly higher than those in the lowest quartile. CONCLUSIONS: Blood pressure was significantly and independently related to plasma insulin level after an oral glucose load in normotensive Japanese men with normal glucose tolerance. The results suggest that the relationship between blood pressure and insulin resistance already exists in a prehypertensive state even in a lean Asian population.

Adult↗

PubMed1995

[The correlation between the levels of anti-Malassezia furfur IgE antibodies and severities of face and neck dermatitis of patients with atopic dermatitis].

It is well known that the seborrheic areas including the face and neck of patients with atopic dermatitis (AD) are frequently affected after adolescence. Malassezia furfur (MF), a lipophilic yeast and a normal habitat of seborrheic areas, has been thought to be one of the most important factors in provoking face and neck lesions of AD. In the present study, we assessed serum levels of anti-MF IgE antibodies by enzyme-linked immunosorbent assay (AlaSTAT method) in 123 adolescent and adult AD patients and evaluated the correlations between levels of anti-MF IgE and those of total IgE and some other allergen-specific IgE. The correlation between the levels of anti-MF IgE and severities of face and neck dermatitis was also assessed. Anti-MF IgE antibodies were detected in high frequency in AD patients (77%), while they were not found in controls. Significant correlations were noted between the levels of anti-MF IgE and those of total IgE and anti-Candida IgE. The levels of anti-MF IgE were well correlated with the severities of face and neck dermatitis. These result may indicate that MF is an important provocative factor for face and neck dermatitis in AD patients.

Adolescent↗

PubMed1995

Ethanol induces heterogeneous reduction of cytochrome aa3 within perfused rat liver lobule assessed using microspectroscopy.

The redox state of cytochrome aa3 was measured at microspots (20 microns diameter) within the lobule of perfused rat livers, using reflectance microspectroscopy, and the effect of ethanol infusion on sublobular distribution of the redox states was evaluated. A sigmoidal relationship was observed between oxygen delivery and the reduction of cytochrome aa3 in both the periportal and pericentral regions of the liver lobule when the influent O2 concentration was decreased in a graduated manner. This sigmoidal curve was shifted to the more reduced state by ethanol infusion, with ethanol (25-100 mM) increasing the degree of cytochrome aa3 reduction in a dose-dependent manner according to the distance from the periportal region along a sinusoid. This increase was spatially heterogeneous within a liver lobule. These data indicate that ethanol accelerates cytochrome aa3 reduction, with a distinct gradient of reduction along sinusoids but a heterogeneous distribution within the liver lobule.

Animals↗

PubMed1995

[Sex determination from dental calculus by polymerase chain reaction (PCR)].

We studied sex determination from dental calculus by the PCR method using primers which recognize DYZ3 region of Y-chromosome and DXZ1 of X-chromosome. The amounts of DNA obtained from 1.7-25.0 mg of dental calculus samples ranged 0.6-26.4 micrograms, and the majority of DNA was low molecular weight DNA. After PCR amplification, Y and X products were observed by the method of polyacrylamide gel electrophoresis. Both Y and X amplification products were observed in 26 out of 29 male samples, while, Y products was not detected in two samples and neither Y nor X product was detected in one sample. In 17 out of 20 female samples, only X product was observed, while, Y and X products were observed in three samples. The minimum amount of DNA for sex determination was 3 pg. Sex determination using DNA in dental calculus will be quite useful for forensic application because it can be done without destruction of morphological characteristics of teeth.

DNA↗

PubMed1995

[Pattern-reversal visual evoked potentials dissociated vertical deviation].

We recorded pattern-reversal visual evoked potentials (P-VEP) from dissociated vertical deviation (DVD) patients to evaluate the sensory system abnormalities in DVD. 91 DVD patients with good visual acuity were studied. Normal subjects and horizontal strabismic patients without DVD were compared for evaluation. Transient and steady state P-VEPs were recorded from three EEG electrodes placed on the posterior scalp. Half-field checker-board reversal stimulation was applied to stimulate monocular temporal retina and responses from right and left hemispheres were also compared for evaluation. Paradoxical lateralization was observed in all normal subjects. Abnormal P-VEPs were observed in 4 of 20 (20%) horizontal strabismic patients without DVD when employing the transient stimulation method and in 2 of 8 (25%) when using steady state stimulation. Abnormal P-VEPs were observed in 31 of 67 (46.3%) DVD patients, with the transient stimulation method and in 20 of 25 (80.0%) DVD patients with the steady state stimulation method. The abnormalities were various and diverse. Our observations indicate that DVD patients frequently have an abnormal sensory system detected by P-VEP, and DVD might be a complex and multi-origin condition involving both sensory and motor systems.

Adolescent↗

PubMed1995

[Detection of myocardial 123I-BMIPP distribution abnormality in patients with ischemic heart disease based on normal data file in bull's-eye polar map].

Visual interpretation of 123I-BMIPP (BMIPP) myocardial images has difficulties in detecting mild reduction in tracer uptake. We studied the significance of the objective assessment of myocardial BMIPP maldistributions at rest by using a Bull's-eye map and its normal data file for detecting ischemic heart disease. Twenty nine patients, 15 with prior myocardial infarction and 14 with effort angina were studied. The initial 15-min BMIPP image was evaluated by visual analysis and by generating the extent Bull's-eye map which exhibits regions with reduced % uptake under mean-2SD of 10 normal controls. The sensitivity for determining coronary lesions in non-infarcted myocardial regions with the extent map was superior to that with visual analysis (67% vs. 33%). In the regions supplied by the stenotic coronary artery, those which showed visually negative but positive in the map and which showed positive in both had higher incidence of wall motion abnormalities and severe coronary stenosis than those with normal findings in both. These results suggest that the objective assessment based on the normal data file in a Bull's-eye polar map is clinically important for improving the limitation of the visual interpretation in 123I-BMIPP imaging.

Adult↗

PubMed1995

Gastric mucosal cell proliferation and TGF alpha in the healing of peptic ulcers in human subjects.

We investigated the role of gastric mucosal proliferation and mucosal transforming growth factor-alpha (TGF alpha) in the healing of peptic ulcers in human subjects. During endoscopic observation, mucosal biopsy specimens were taken from the ulcer margin for flow cytometric analysis of the mucosal cell cycle and ELISA for mucosal TGF alpha content. Immunohistochemistry confirmed that biopsy specimens contained proliferating gastric epithelial cells, TGF alpha, and the TGF alpha receptor. When the stage of ulcer healing was categorized according to Sakita and Miwa, mucosal cell proliferation was less at active stages and gradually increased during the healing process. The mucosal TGF alpha level at the ulcer margin was not detectable at the A1 stage but increased to within the normal range during ulcer healing. After re-establishment of the epithelial layer at the site of the ulcer, cell proliferation returned to normal and TGF alpha remained within the normal range. Immunohistochemistry showed coexistence of TGF alpha and its receptor within PCNA-positive proliferating cells. These results suggest that TGF alpha and its receptor play an important role in gastric epithelial cell replication. The increase in TGF alpha at the ulcer margin might indicate a role in stimulation of gastric cell replication during ulcer healing.

Adult↗

PubMed1995

The inflammatory reaction in mucosa during healing of gastric ulcers in humans.

To evaluate the inflammatory changes during ulcer healing, we measured myeloperoxidase (MPO) activity and the inflammatory cytokine interleukin-8 (IL-8) in the gastric mucosa of 51 patients with gastric ulcers and 5 normal controls. MPO activity was measured by enzyme assay and IL-8 by ELISA, using biopsy samples taken from the ulcer margin and at 3 and 6 cm from the ulcer. Levels of MPO activity were significantly higher than in normal controls and peaked at the A2 (active) stage, and then gradually decreased and returned to basal levels at the S2 (scarring) stage. The area of increased MPO activity around the gastric ulcer was approximately 6 cm in diameter at the A2 stage, and this area decreased as the ulcer healed. IL-8 levels in gastric mucosa also increased significantly at the A2 stage, and the changes paralleled those of MPO activity during ulcer healing. MPO activity correlated well with the IL-8 level.

Biopsy↗

PubMed1994

Increased expression of c-met messenger RNA following acute gastric injury in rats.

The aim of the present study was to evaluate messenger RNA expression of c-met, a hepatocyte growth factor receptor gene, after gastric mucosal injury in rats. Male Sprague-Dawley rats were fasted for 24 hours, received 0.6 N hydrochloric acid (HCl), and served for polyadenylated RNA extraction from the oxyntic gastric mucosa. The transcripts of rat c-met gene were analyzed by reverse-transcript polymerase chain reaction and Northern blotting. Although it was detected even before the HCl administration, the c-met expression increased 6, 24 and 48 hours after the HCl administration. Thereafter, gastric mucosal injury diminished and the c-met expression declined. Hepatocyte growth factor reportedly plays an important role in gastric cell proliferation. The increased c-met expression indicates that this gene may participate in the healing process of gastric mucosa after injury.

Amino Acid Sequence↗

PubMed1994

CD21 antigen in T-lineage neoplastic lymphoid cells: characteristic expression at thymic stage.

The expression of CD21 antigen, a receptor for the C3d fragment of complement and Epstein-Barr virus (EBV), was investigated in a total of 85 cases of neoplastic lymphoid cells including 39 cases of T-lineage acute lymphoblastic leukemia (ALL)/lymphoblastic lymphoma (LBL), although CD21 antigen is usually regarded as a pan-B antigen. The CD21 antigen was expressed by one of the eight cases of neoplastic lymphoid cells expressing the CD7 antigen as a sole pan-T antigen, by three of the 20 cases of pro- or early thymic stage (CD7+ CD5+ CD2-, CD7+ CD5- CD2+, or CD7+ CD5+ CD2+, and ten of 11 cases of thymic stage (CD3+/- CD4+ CD8+), but not by one case of late thymic stage (CD3+ CD4+ CD8-) T-ALL/LBL cells. The CD21 antigen was not expressed by any of the 11 cases of adult T-cell leukemia (ATL) or two cases of chronic T-lineage leukemia. At most 4% of the normal thymocytes obtained from seven infants or children expressed the CD21 antigen. While only a very limited population of normal thymocytes expresses CD21 antigen, T-ALL/LBL cells at the thymic stage characteristically express CD21 antigen in contrast to pro- or early thymic ALL/LBL or peripheral-stage neoplastic T cells. The estimation of the expression of CD21 antigen is useful for delineating stages of differentiation in T-ALL/LBL. Furthermore, these observation are notable, considering the possibility that the reported EBV-carrying T-cell lymphomas result from the penetration of EBV into EBV-negative neoplastic T cells.

Adolescent↗

PubMed1994

Endothelin-1 is involved in the pathogenesis of ischemia/reperfusion liver injury by hepatic microcirculatory disturbances.

Hepatic microcirculatory perturbation is observed after ischemia/reperfusion. Endothelin-1, a potent vasoconstrictive peptide, is known to modulate local circulation. This study was designed to examine whether endothelin-1 participates in the mechanism of microcirculatory disturbance and damage of the liver after ischemia/reperfusion. Ischemia in the median and left lateral lobes of the liver was induced for 60 min; it was followed by reperfusion for 24 hr. In some rats, endothelin-1 antiserum or control serum without endothelin-1-blocking activity was administered intravenously just before reperfusion. Rats were divided into three groups: an ischemia/reperfusion group that was injected with control serum, an endothelin-1 antiserum-treated group and a sham-operated group. Endothelin-1 concentrations in blood collected from the suprahepatic vena cava were measured before and after ischemia/reperfusion by use of a sandwich enzyme immunoassay. Index of blood volume in regional hepatic tissue and index of blood oxygenation in regional hepatic tissue were assessed with an organ reflectance spectrophotometry system before and at 5 min and 1, 2, and 24 hr after reperfusion. The endothelin-1 concentration in the ischemia/reperfusion group started to rise immediately at onset of reperfusion from basal values around 1 pg/ml and reached a value of 5 to 6 pg/ml 5 min after reperfusion; it was maintained at significantly high levels during the reperfusion period compared with the sham-operated group. Hepatic microcirculatory disturbance indicated by lowered index of blood volume in regional hepatic tissue and index of blood oxygenation in regional hepatic tissue levels was observed in the early phase of reperfusion in the ischemia/reperfusion group.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine Transaminase↗

PubMed1994

Endogenous nitric oxide attenuates ethanol-induced perturbation of hepatic circulation in the isolated perfused rat liver.

The purpose of this study was to clarify the role of endogenous nitric oxide in ethanol-induced perturbation of microcirculation and hepatic injury in perfused rat liver. Infusion of ethanol into the portal vein at 25 and 100 mmol/L increased portal pressure, which is an indicator of hepatic vasoconstriction, in a concentration-dependent fashion. Portal pressure started to rise immediately after ethanol load, then decreased gradually and remained at higher than basal levels throughout the period of ethanol infusion. Release of lactate dehydrogenase into the effluent perfusate began to increase after 30 min of ethanol infusion and continued to increase during the 60-min period of ethanol infusion. The lactate dehydrogenase level in the effluent perfusate at 60 min was dependent on the ethanol concentration (0 mmol/L, 8 +/- 3 IU/L; 25 mmol/L, 16 +/- 2 IU/L; 100 mmol/L, 52 +/- 6 IU/L). Simultaneous infusion of NG-monomethyl-L-arginine, a nitric oxide synthesis inhibitor, enhanced significantly the ethanol-induced increase in portal pressure by 100% to 400% and increased lactate dehydrogenase release by 40% to 80%. The effect of NG-monomethyl-L-arginine on the ethanol-induced increase in portal pressure was completely reversed by the co-infusion of an excess dose of L-arginine. Change in portal pressure averaged over 60 min of ethanol infusion correlated with levels of lactate dehydrogenase release 60 min after the initiation of ethanol infusion (r = 0.77, p < 0.01). In conclusion, inhibition of the action of endogenous nitric oxide was associated with an increase in hepatic vasoconstriction and hepatocellular damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1994

Prognostic factors of renal dysfunction induced by environmental cadmium pollution.

To assess the influence of environmental cadmium (Cd) exposure on long-term outcome, a follow-up study was conducted from 1981-1982 to March 1991 on 3178 inhabitants living in the Cd-polluted Kakehashi River basin. The standardized mortality ratios of the urinary beta 2-microglobulin (beta 2-MG)-, protein-, and amino acid-positive subjects of both sexes and the urinary glucose-positive female subjects were higher than those of the subjects with urinary-negative findings or the general Japanese population during the observation period. After adjusting for age using Cox's proportional hazards model, significant associations were found between mortality and urinary indices. In multiple comparisons using all of the indices, urinary protein and beta 2-MG in the women and urinary protein in the men were the factors most contributing to the mortality rates. In the urinary protein-negative female group as well, a significant association was found between urinary beta 2-MG and mortality. These results suggest that the prognosis of subjects with Cd-induced renal dysfunction is unfavorable, with the mortality rate increasing even in the early stage of proximal tubular dysfunction. Urinary protein and urinary beta 2-MG are important prognostic factors, with the latter, in particular, considered to be useful as an early index predictive of premature mortality.

Amino Acids↗

PubMed1994

Physical map of the plastid genome of the unicellular red alga Cyanidium caldarium strain RK-1.

The physical map of the plasmid genome of the unicellular red alga Cyanidium caldarium strain RK-1 was constructed. The 150-kbp genome was circular and had an inverted repeated region (IR) which contained the genes for 16 s and 23 s ribosomal RNAs, as is usually seen in most plastid genomes. Since C. caldarium is a very "primitive" alga, the results suggest that the ancestral cyanobacteria lost most of its genome as an endosymbiont comparatively early in the process of plastid formation. After that, several genes seem to have been lost from plastid genomes, step by step, during the course of evolution.

Amino Acid Sequence↗

PubMed1994

The trpA gene on the plastid genome of Cyanidium caldarium strain RK-1.

The trpA gene (for the alpha subunit of tryptophan synthase) was found on the plastid genome of the "primitive" unicellular red alga Cyanidium caldarium strain RK-1. This is the first example of an actively-transcribed gene for tryptophan synthase encoded on a plastid genome. In contrast to trpA, trpB (the gene for the beta subunit of tryptophan synthase) was encoded in the cell nucleus. Considering the primitive characteristics of C. caldarium, trpB must have been lost from the plastid genome before trpA.

Amino Acid Sequence↗