Biomedical subjects

K Higuchi

Publications and source records attributed to K Higuchi.

At least 217 records · Page 12Linked to original sources

PubMed1997

Characteristics of juvenile dermatomyositis in Japan.

Questionnaires were sent to 1290 hospitals in Japan asking for data on patients with juvenile dermatomyositis (JDM) diagnosed between June 1984 and May 1994. Of the 204 patients identified by these questionnaires, 102 met the criteria for JDM. JDM is categorized into three subtypes: Banker-type JDM, Brunsting-type and fulminant-type; patients with the latter exhibit markedly elevated serum levels of creatinine phosphokinase (> 10,000 U/mL) and appear to be at risk of renal failure. Cutaneous manifestations were present in 98% of patients and preceded the appearance of other symptoms. This tendency is one of the reasons for the difficulty in some cases in diagnosing the onset of JDM. Better criteria for early treatment of JDM are needed. The results of the present study suggest that itching and calcinosis are factors that indicate a poor prognosis in patients with JDM. Muscle enzyme levels do not always reflect disease activity, suggesting that methods other than measurement of muscle enzymes, such as measurement of the levels of neoprerin and von Willebrand factor antigen, as well as magnetic resonance imaging should be used to be evaluate disease severity. Patients with Brunsting-type JDM who exhibit dysphagia and antinuclear antibody positivity and patients with Banker-type JDM should be treated aggressively. Pulse therapy should be selected as the initial therapy in patients with fulminant-type JDM.

Child↗

PubMed1997

Clonal accumulation of V beta 5.1-positive cells in the liver of a patient with autoimmune cholangiopathy.

We describe a 43-year-old woman with clinical features compatible with autoimmune cholangiopathy recently reported by Ben Ari et al. She was negative for anti-mitochondrial antibody, positive for high titer anti-nuclear antibody with homogeneous pattern, high levels of serum immunoglobulin G and nearly normal levels of serum immunoglobulin M for more than five years. In the early stages of the disease, the elevations of serum transaminase, alkaline phosphatase and gamma-glutamyl transpeptidase were well controlled by the administration of ursodeoxycholic acid. After five years of follow-up, she showed the second exacerbation of liver function tests, which then rapidly improved by prednisone administration. To analyze the antigen diversity recognized by T-cells in the liver, T-cell receptor repertoire was examined by immuno-histochemistry. The liver biopsy obtained in the early stage showed clonal accumulation of V beta 5.1-positive cells in portal areas, which was found in patients neither with primary biliary cirrhosis nor autoimmune hepatitis. In conclusion, these data suggest that T-cell response in autoimmune cholangiopathy is different from those two autoimmune liver diseases, which may imply a distinct entity of the disease.

Adult↗

PubMed1997

Ventricular tachycardia initiated by high energy cardioversion in a patient with an implantable cardioverter defibrillator.

A transvenous implantable cardioverter defibrillator (ICD) was implanted into a 58 year old woman with idiopathic dilated cardiomyopathy who had drug refractory monomorphic ventricular tachycardia (VT). Antitachycardia pacing failed to terminate the VT; termination was attempted at 24 J, which was above the defibrillation threshold. When cardioversion at 24 J was delivered, VT with a different morphology and slower rate was reproducibly initiated. At 3 J, however, the original VT was successfully terminated without initiation of the slower VT. A new VT may be induced by high energy cardioversion. This may be a manifestation of the proarrhythmic potential of ICDs.

Cardiomyopathy, Dilated↗

PubMed1997

Involvement of capsaicin-sensitive sensory nerves in gastric adaptive relaxation in isolated guinea-pig stomachs.

We investigated the role of capsaicin-sensitive sensory nerves (CPSNs), nitric oxide (NO), calcitonin gene-related peptide (CGRP) and vasoactive intestinal peptide (VIP) in gastric adaptive and receptive relaxation in isolated guineapig stomachs. Changes in intragastric volume and pressure were recorded simultaneously in isolated stomachs in baths containing atropine and guanethidine. Adaptive relaxation was induced by luminal distention, and receptive relaxation was induced by electrical vagal stimulation. We found that desensitization to capsaicin inhibited adaptive relaxation, but not vagally induced relaxation. Extraluminal capsaicin induced gastric relaxation. Adaptive relaxation and capsaicin-induced relaxation were reduced by both tetrodotoxin and NG-nitro-L-arginine (LNNA), but not by hexamethonium. The effect of LNNA was partially reversed by co-incubation with L-arginine. Neither CGRP(8-37) nor VIP(10-28) inhibited all responses of adaptive relaxation, vagally induced and capsaicin-induced relaxation. These findings suggest that activation of CPSNs may be involved in adaptive relaxation, and that NO, but not CGRP or VIP, may be involved in the mechanisms of adaptive relaxation and receptive relaxation.

Adaptation, Physiological↗

PubMed1997

A novel NADP(+)-dependent serine dehydrogenase from Agrobacterium tumefaciens.

NADP(+)-dependent serine dehydrogenase [EC 1.1.1.-], which catalyzes the oxidation of the hydroxyl group of serine to form 2-aminomalonate semialdehyde, was purified to homogeneity from a crude extract of Agrobacterium tumefaciens ICR 1600. The enzyme had a molecular mass of about 100 kDa and consisted of four identical subunits. In addition to L-serine, D-serine, L-glycerate, D-glycerate, and 2-methyl-DL-serine were substrates. However, O-methyl-DL-serine and L-threonine were inert. The enzyme showed maximal activity at about pH 9 for the oxidation of L-serine. The enzyme required NADP+ as a coenzyme, NAD+ was inert. The enzyme was not inhibited by EDTA, o-phenanthroline, or alpha,alpha'-dipyridyl, but was inhibited by HgCl2, p-chloromercuribenzoate, L-cysteine, D-cysteine, malonate, 2-methylmalonate, and tartronate. The Michaelis constants for L-serine, D-serine, and NADP+ were 42, 44, and 0.029 mM, respectively.

Absorption↗

PubMed1997

New aspects of gastric adaptive relaxation, reflex after food intake for more food: involvement of capsaicin-sensitive sensory nerves and nitric oxide.

To accommodate the intake of food or liquid, gastric reservoir functions are important as the physiological reflex. There exist two major responses as a reservoir function of the stomach; adaptive and receptive relaxations. Adaptive relaxation is a reflex in which the fundus of the stomach dilates in response to small increases in intragastric pressure when food enters the stomach. Receptive relaxation is a reflex in which the gastric fundus dilates when food passes down the pharynx and the esophagus. The mechanisms of these two types of functional responses are to some extent different, although a nitric oxide (NO) dependent non adrenergic, non cholinergic neural pathway is involved in the both relaxation reflexes. Adaptive relaxation is an intragastric pressure induced reflex. Stretch of the gastric wall activates the mechanoreceptors in gastric mucosa (Mu), which generate impulses carried by the capsaicin-sensitive afferent sensory neuron. The sensory neuron can synapse on the inhibitory efferent neuron directly or activate it via interneurons of the myenteric plexus. This leads to the release of NO from the nitroxergic efferent neuron, which causes relaxation of circular muscle and hence of the fundus. Alternatively, an axon reflex causes the NO release from the sensory neuron, resulting in hexamethonium resistant gastric relaxation. Receptive relaxation is mediated by vagal motor fibers. In contrast with the pressure-induced adaptive relaxation, ganglionic nicotinic transmission is essential in the vagally induced relaxation. VIP and CGRP are important neurotransmitters of the inhibitory sensory neuron, which, however, may not mediate both adaptive and receptive relaxations. Disorders of these reservoir functions result in symptoms of early satiety and anorexia, which are the major symptoms of patients with functional dyspepsia.

Adaptation, Physiological↗

PubMed1997

Fourteen-day oral combination dose toxicity study of CGS 16949 A (aromatase inhibitor) with 5-fluorouracil or tamoxifen in rats.

CGS 16949A, an aromatase inhibitor, was administered orally to female rats at doses of 1 and 10 mg/kg/day alone and in combination with tamoxifen (0.5 or 5 mg/kg/day) or 5-fluorouracil (20 mg/kg/day) for 14 days. CGS 16949A and tamoxifen combination: Increased food intake and body weight noted after CGS 16949A treatment were also observed following combination treatment, though to a lesser degree. Most of the clinical pathological features noted following combination treatment were similar to those induced by single compound treatment. Gross pathological and histopathological changes ascribed to the antiestrogenic action of CGS 16949A, such as increased ovarian weight, decreased uterine weight, cystic follicles and atrophied uterus and vaginal epithelium, were alleviated by combination treatment, and were comparable in severity to those caused by tamoxifen alone. No severe toxic changes were induced by combination treatment. CGS 16949A and 5-fluorouracil combination: Increased body weight noted after CGS 16949A treatment was also observed following combination treatment, though to a lesser degree. Most of the changes caused by single compound treatment, including the aforementioned effects of CGS 16949A on the genital organs, were also noted following combination treatment. There was no evidence of enhancement of the effects by combination treatment.

Administration, Oral↗

PubMed1997

Role of neutrophils in a rat model of gastric ulcer recurrence caused by interleukin-1 beta.

The production of several cytokines such as interleukin (IL)-1 in gastric mucosa is increased in subjects infected with Helicobacter pylori, a bacterium associated with ulcer recurrence. This study was performed to determine whether the administration of IL-1 beta can cause recurrence of gastric ulcers in rats. Rats with healed ulcers received an injection of IL-1 beta (0.01 to 1 microgram/kg) or vehicle alone. Some rats received an injection of antiserum to rat neutrophils at the same time as 1 microgram/kg IL-1 beta or an injection of monoclonal antibodies against adhesion molecules (anti-intercellular adhesion molecule-1, anti-CD11a, and anti-CD11b) at 0, 12, and 24 hours after the initial injection. At this dose of IL-1 beta, the numbers of neutrophils and monocytes/macrophages infiltrating the scarred mucosa were higher at 12 and 24 hours than without injection of IL-1 beta. By 48 hours, seven of the eight bealed ulcers in the group treated with 1 microgram/kg IL-1 beta had recurred, as had one of the seven healed ulcers in the group given 0.1 microgram/kg IL-1 beta. No recurrence was found in the rats treated with 0.01 microgram/kg IL-1 beta or vehicle alone. Treatment with antiserum to neutrophils or antibodies to adhesion molecules inhibited both neutrophil infiltration into the scarred mucosa and the ulcer recurrence caused by IL-1 beta. These findings suggest possible mechanisms of recurrence of human peptic ulcers.

Acetic Acid↗

PubMed1997

[Two cases of annulo-aortic ectasia with type A aortic dissection reconstructed by reimplantation of the aortic valve].

We performed aortic valve sparing operation in two cases of annulo-aortic ectasia combined with Type A aortic dissection. Marfan syndrome was found in one case and the dissection was acutely evolving in another case. The aortic valves were observed as normal configuration in both cases and then reimplanted within the synthetic grafts along with the David's procedure. No aortic regurgitation was found in the acute case but slight regurgitation was checked out in the Marfan case at the discharge. The aortic valve preserving operation for annulo-aortic ectasia was considered much effective in cases with aortic dissection in order to expect the thrombolization in the pseudo lumen.

Adult↗

PubMed1997

Amyloid A protein amyloidosis induced in apolipoprotein-E-deficient mice.

Apolipoprotein E (apoE) is a constituent of lipoproteins other than low-density lipoprotein, and it principally acts in the transport and metabolism of plasma cholesterol and triglyceride. ApoE is a minor constituent of various kinds of amyloidoses and may play a role as a pathological chaperone for fibrillogenesis of amyloid fibril protein with the amyloid P component and proteoglycans. In this study, we examined the role of apoE in amyloidogenesis in vivo in apoE-deficient mutant mice with amyloid A protein (AA) amyloidosis induced by inflammatory stimulation. Amyloid deposition was seen in six of nine C57BL/6J control mice and in six of eight apoE-deficient mutant mice after the intraperitoneal and subcutaneous injections of the mixture of complete Freund's adjuvant and Mycobacterium butyricum. Moreover, amyloid deposition in apoE-deficient mice as well as C57BL/6J control mice started 48 or 72 hours after injection of amyloid-enhancing factor and silver nitrate, although the amount of amyloid deposit in C57BL/6J control mice was slightly larger than that in apoE-deficient mice. These amyloid deposits reacted with anti-mouse AA antibody were seen in the perifollicular area of the spleen. Immunoreactivity of apoE was seen irregularly in the amyloid deposits of C57BL/6J control mice but not in the amyloid deposit of apoE-deficient mice. From these results, we concluded that apoE is not always necessary for amyloid deposition and that the existence of apoE might slightly accelerate AA amyloid deposition in the earliest phase of AA amyloid deposition.

Amyloidosis↗

PubMed1997

[A case of CABG under the cardiac arrest induced by a short acting beta-blocker without clamping the aorta].

A seventy one year old woman had a coronary artery bypass grafting. No touch technique to her ascending aorta was applied due to the severely atherosclerotic aorta. Cardiac arrest was induced by a large dose of short acting beta-blocker (Esmolol) without cross-clamping the aorta under the normothermic cardio-pulmonary bypass. The heart was flaccid and rotated easily while the coronary anastomoses were performed. Both of the internal thoracic arteries were grafted individually to the anterior descending artery and to the circumflex artery. The cardiac beats were resumed with the ordinary inotropic support and then the cardio-pulmonary bypass was weaned off. Her postoperative course was uneventful and the cardiac enzyme level was not elevated. Both of the grafts were revealed patent by the postoperative angiography. Esmolol had played an important roll to perform excellent anastomoses and to protect the myocardium. It was concluded that this technique could be one of the suitable modality for patients with diseased aorta and further studies should be pursued concerning Esmolol as an alternative to the conventional cardioplegia.

Adrenergic beta-Antagonists↗

PubMed1997

[Effects of neoadjuvant intra-arterial infusion chemotherapy in patients with stage III breast carcinoma].

From 1991 to 1996, we performed neoadjuvant intra-arterial infusion chemotherapy in 5 eligible patients among 21 patients with Stage III breast carcinoma. The treatment regimen for neoadjuvant chemotherapy was intra-arterial Epirubicin (EPR) on Day 1, 3, 5, 7 combined with endocrine therapy (MPA 1,200 mg). The effects of the treatment were compared among 8 patients given adjuvant intravenous chemotherapy. The clinical response rate was 100% with all partial response and metastatic lymph nodes were disappeared histologically in 2 cases. The median disease-free interval and overall survivals are 44 months (range 28-64) and 48 months (range 28-64), respectively. Neoadjuvant (intra-arterial) group had a longer disease-free interval than the adjuvant (intravenous) group. We are applying this treatment for down staging, and it is possible to use minimal invasive surgery for cure of stage III breast carcinoma.

Adult↗

PubMed1997

Autoimmune hepatitis types IIa and IV in young men.

Two young men with autoimmune hepatitis types IIa and IV are reported here. These rare types of the disease could be diagnosed by using the diagnostic criteria for scoring of autoimmune hepatitis established by the International Group.

Actins↗

PubMed1996

Myocardial infarction as a complication of pheochromocytoma in a pregnant woman.

Pheochromocytoma is an unusual cause of hypertension during pregnancy. We present a 40-year-old woman who had a myocardial infarction during pregnancy in whom pheochromocytoma was subsequently diagnosed. This disorder carries a high risk of maternal and perinatal mortality, if undiagnosed prior to delivery. Therefore, the diagnosis of pheochromocytoma should be considered in pregnant patients who exhibit a marked fluctuation in hypertension. Urinary concentrations of catecholamines and their metabolites should be measured in such cases.

Adrenal Gland Neoplasms↗

PubMed1996

Indomethacin treatment during initial period of acetic acid-induced rat gastric ulcer healing promotes persistent polymorphonuclear cell-infiltration and increases future ulcer recurrence. Possible mediation of prostaglandins.

The study was performed to examine whether indomethacin administered during the initial period of acetic acid-induced gastric ulcer healing affects future ulcer recurrence. Gastric ulcers were produced in rats by subserosal injection of acetic acid. Indomethacin (1 mg/kg/day, orally) administered either alone or concomitant with ornoprostil (50 micrograms/kg/day, orally) was started on the fourth day and continued for 56 days. In rats whose ulcer healed at the 90th day after production of ulcer, endoscopy was done every 30 days to examine recurrence of ulcer. Gastric specimens were obtained 10, 30, 60, 90, and 240 days after ulcer production for histology, to quantitate the height of regenerated mucosa, thickness of fibrous tissue, degree of polymorphonuclear cell infiltration, and PAS-positive cells. Cumulative ulcer recurrence rate was significantly higher in rats initially treated with indomethacin than in controls. Increased polymorphonuclear cell infiltration was the major histologic abnormality persisting after cessation of indomethacin. Ornoprostil reversed these abnormalities caused by indomethacin. In conclusion, the administration of indomethacin during the initial period of the ulcer healing promoted persistent polymorphonuclear cell infiltration and increased ulcer recurrence rates, possibly via a prostaglandin-dependent mechanism.

Alprostadil↗

PubMed1996

Expression and localization of basic fibroblast growth factor (bFGF) in the repair process of rat liver injury.

BACKGROUND/AIMS: To clarify the expression and localization of basic fibroblast growth factor in the repair process of liver injury, acute liver injury was induced by administration of carbon tetrachloride, D-glactosamine hydrochloride, or dimethylnitrosamine to rats. METHODS: We measured basic fibroblast growth factor protein in the liver tissue by radioimmunoassay, evaluated the expression of basic fibroblast growth factor mRNA by the reverse transcriptase polymerase chain reaction, and identified basic fibroblast growth factor-positive cells by immunostaining. RESULTS: In the carbon tetrachloride injured liver, the basic fibroblast growth factor protein contents began to increase 2 days after administration when liver injury was most marked, and reached a peak after 4 days, decreasing thereafter. In the carbon tetrachloride-injured liver, basic fibroblast growth factor mRNA expression was observed from 12 h after administration, prior to an increase in the protein content. In the D-galactosamine hydrochloride-injured liver, basic fibroblast growth factor protein also increased. On the other hand, in the dimethylnitrosamine-injured liver, the basic fibroblast growth factor protein content decreased 2 days after administration when liver injury was marked, but increased after 7 days. In the regenerating liver after partial hepatectomy, the basic fibroblast growth factor protein content did not increase. Among cell fractions, the Ito cell fraction obtained from the carbon tetrachloride-injured liver after 4 days showed expression of basic fibroblast growth factor mRNA. In cells cultured for 24 h, this fraction was immunopositive for basic fibroblast growth factor. Ito cells in the liver tissue markedly increased in the carbon tetrachloride-injured liver and increased after 7 days in the dimethylnitrosamine-injured liver. CONCLUSIONS: This study confirmed basic fibroblast growth factor production in the liver tissue in the repair process of liver injury. Our results suggest that basic fibroblast growth factor is primarily produced in Ito cells, acts on sinusoidal wall cells including Ito cells by the autocrine and paracrine mechanisms, and promotes extracellular matrix production and vascularization, involving the repair process of liver injury.

Animals↗

PubMed1996

Larvicidal activity of Bacillus thuringiensis natural isolates; indigenous to Japan, against two nematoceran insect pests occurring in urban sewage environments.

A total of 1449 Bacillus thuringiensis strains, indigenous to Japan, were screened for larvicidal activity against two nematoceran insect pests, the mosquito, Culex pipiens molestus (Culicidae), and the moth-fly, Telmatoscopus albipunctatus (Psychodidae). Mosquito specific strains were abundant in H serotypes 3abc (serovar kurstaki), 3ade (fukuokaensis), 4ac (kenyae), 7 (aizawai), 11ac (kyushuensis) and 29 (amagiensis), while moth-fly specific strains were predominantly found in H serotype 17 (tohokuensis). Strains toxic to both insects were most frequently detected in H serotypes 10 (darmstadiensis) and 17/27. Seven selected B. thuringiensis strains were highly toxic to Culex and/or Telmatoscopus. There was a diversity in SDS-PAGE profiles of inclusion proteins of these strains.

Animals↗

PubMed1996

Diagnosis of borderline adenomas of the stomach by endoscopic mucosal resection.

BACKGROUND AND STUDY AIMS: The correct histological diagnosis of gastric borderline adenomas is often difficult, especially in excluding malignancy, since the usual diagnostic methods, such as radiography and histological examination of forceps biopsy specimens, are of limited accuracy. The aim of this study was to retrospectively analyze the value of endoscopic mucosal resection in establishing the correct diagnosis of borderline adenomas. RESULTS: Fourteen borderline adenomas were finally diagnosed as containing early gastric cancer type IIa (well-differentiated tubular adenocarcinoma) after endoscopic mucosal resection, of the remaining 36 tubular adenomas, six represented mild dysplasia, 24 moderate dysplasia, and six severe dysplasia. Most parts of the 14 adenomas containing early gastric cancers had regions of structural atypia, and cellular atypia was moderate in all. Seven of 14 cancers were completely resected, all patients being tumor-free after a follow-up of 33-61 months. CONCLUSIONS: These results suggest that diagnosing borderline adenoma on the basis of radiographic and endoscopic-bioptic findings is generally unreliable, because biopsy specimens may not be representative of the entire lesion. Borderline adenomas of the stomach should be completely resected by endoscopic mucosal resection to obtain a final diagnosis and - depending on the size and type of the lesion - possibly also definitive treatment.

Adenoma↗