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Biomedical subjects

T Murai

Publications and source records attributed to T Murai.

At least 73 records · Page 4Linked to original sources
PubMed1999

The influence of psychotic states on the autonomic nervous system in schizophrenia.

Abnormal autonomic activity in patients with schizophrenia has been reported, but how psychotic states influence the autonomic nervous system (ANS) has remained unclear due to methodological limitations. The influence of psychotic states on ANS activity in patients with schizophrenia was investigated using a recently developed method of analysis based on heart rate variability which assesses cardiac sympathetic and parasympathetic function separately. Cardiac autonomic function (CAF), together with psychotic states, was assessed at the beginning and the end of an 8-week study period in 53 patients with chronic schizophrenia. The CAF in age- and sex-matched control subjects was also examined. There were no significant differences between the patients and the control subjects in the mean R-R interval (RRI) or in the indices of the sympathetic and the parasympathetic function. In the patients who changed in psychotic states, the parasympathetic index was significantly decreased without significant changes in the sympathetic index when their psychotic states were more pronounced, suggesting psychotic states suppressed the parasympathetic function without affecting the sympathetic function. In these patients, the mean RRI was smaller when their psychotic states were more pronounced. Our results demonstrate that psychotic states affect the ANS, suggesting a relationship between cerebral cognitive and peripheral ANS activities, and that this is presumably mediated through the parasympathetic nervous system. These findings are discussed in comparison with previous reports on the CAF in schizophrenia.

Adult↗
PubMed1999

Ammonia, hydrogen peroxide, and monochloramine retard gastric epithelial restoration in rabbit cultured cell model.

Ammonia (NH3), hydrogen peroxide (H2O2) and monochloramine (NH2Cl) produced by Helicobacter pylori infection might be responsible for mucosal injury. The aim of this study was to evaluate the role of NH3, H2O2, and NH2Cl in the restoration of rabbit primary cultured gastric mucosal cells with a wound repair model. Artificial wounds were made in confluent monolayer gastric epithelial cell sheets by mechanical denudation, and changes in the size of the cell-free area were analyzed quantitatively. Cell proliferation was assessed by bromodeoxyuridine staining. In controls, the wound healed within 48 hr. However, mucosal cell repair was inhibited by treatment with NH3, H2O2, and NH2Cl in a dose-dependent manner. These results indicate that NH3, H2O2, and NH2Cl retarded the wound healing, which included epithelial cell migration and proliferation of gastric mucosa. Therefore, it is suggested that NH3, H2O2, and NH2Cl delays the healing process of peptic ulcers.

Ammonia↗
PubMed1999

Levcromakalim causes indirect endothelial hyperpolarization via a myo-endothelial pathway.

1. Effects of K+ channel opener, levcromakalim, on vascular endothelial cells were examined. Under voltage- and current-clamp conditions, application of acetylcholine to dispersed endothelial cells isolated from rabbit superior mesenteric artery (dispersed RMAECs) produced hyperpolarization and outward currents. On the other hand, dispersed RMAECs did not respond to levcromakalim. 2. When membrane potential was recorded from endothelium in a mesenteric arterial segment, exposure to levcromakalim in a concentration range of 0.1 to 3 microM caused concentration-dependent hyperpolarization. The hyperpolarization was observed in the absence of external Ca2+ and was inhibited by 10 microM glibenclamide. 3. The presence of 1 mM heptanol did not affect the levcromakalin-induced hyperpolarization, whereas treatment of the mesenteric arterial segment with 20 microM 18 beta-glycyrrhetinic acid significantly reduced the hyperpolarization. The response to acetylcholine of RMAECs in an arterial segment with 18 beta-glycyrrhetinic acid was, however, similar to that without 18 beta-glycyrrhetinic acid. 4. These suggest that although RMAECs themselves are functionally insensitive to levcromakalim, those in an arterial segment are hyperpolarized by levcromakalim via myo-endothelial electrical communication.

Animals↗
PubMed1999

Impact of rabeprazole, a new proton pump inhibitor, in triple therapy for Helicobacter pylori infection-comparison with omeprazole and lansoprazole.

BACKGROUND: A recent trend in curative therapy for Helicobacter pylori infection is the so-called triple therapy, which consists of a proton pump inhibitor (PPI) and two different antimicrobials. Various regimens employing this triple therapy have been reported. However, little is known about the effectiveness of rabeprazole, a recently developed proton pump inhibitor, when used in the triple therapy. AIM: To validate its usefulness by comparing rabeprazole with omeprazole and lansoprazole, in combination with amoxycillin and clarithromycin. PATIENTS AND METHODS: 221 H. pylori-positive patients with peptic ulcer disease were randomized to receive one of three different proton pump inhibitor/amoxycillin-clarithromycin (PPI/AC) regimens for 7 days. (i) OAC regimen (n = 75): omeprazole 20 mg b.d., amoxycillin (AMOX) 500 mg t.d.s. and clarithromycin (CAM) 200 mg b.d.; (ii) LAC regimen (n = 74): lansoprazole 30 mg b.d. , AMOX 500 mg t.d.s. and CAM 200 mg b.d.; and (iii) RAC regimen (n = 72): rabeprazole 20 mg b.d., AMOX 500 mg t.d.s. and CAM 200 mg b.d. Cure of the infection was determined by the 13C urea breath test 1 month after completion of the treatment. RESULTS: Intention-to-treat based cure rates for OAC, LAC and RAC regimens were 85% (95% CI, 75-92), 84% (95%, CI 73-91) and 88% (95% CI, 78-94), respectively, and per protocol based cure rates of these regimens were 88% (95% CI, 78-94), 91% (95%, CI 82-99) and 93% (95% CI, 84-98), respectively. Adverse effects in the entire study population, which included diarrhoea, glossitis or skin rash, were reported by 15% of the patients, and complete compliance was achieved in 95% of these patients. CONCLUSION: 1-week proton pump inhibitor/AC regimens for H. pylori infection were effective in the Japanese population. Rabeprazole can be considered as equivalent to omeprazole and lansoprazole in the PPI/AC triple therapy.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Efficacy of 1 week omeprazole or lansoprazole-amoxycillin-clarithromycin therapy for Helicobacter pylori infection in the Japanese population.

BACKGROUND: The effectiveness of curative therapy for Helicobacter pylori may vary according to the geographic region and patient population, thus the efficacy of each treatment regimen should be determined according to the specific patient population. However, there is no literature available concerning the efficacy of 1 week omeprazole-amoxycillin-clarithromycin (OAC) regimens for the cure of H. pylori infection in Japan. METHODS: Helicobacter pylori-positive patients (224) with peptic ulcer disease or non-ulcer dyspepsia were randomized to receive one of three different omeprazole or lansoprazole-amoxycillin-clarithromycin (PPI/AC) regimens for 7 days: (1) OAC 20 regimen (n = 76), omeprazole (OPZ) 20 mg daily, amoxycillin (AMOX) 500 mg t.d.s. and clarithromycin (CAM) 200 mg b.d.; (2) LAC 30 regimen (n = 73), Lansoprazole (LPZ) 30 mg daily, AMOX 500 mg t.d.s. and CAM 200 mg b.d.; and (3) OPZ 40 regimen (n = 75), OPZ 20 b.d., AMOX 500 mg t.d.s. and CAM 200 mg b.d. Cure of the infection was determined by the [13C]-urea breath test, 1 month after completion of the treatment. RESULTS: Intention-to-treat based cure rates for OAC 20, LAC 30 and OAC 40 regimens were 75.0% (95% CI, 64-84%), 82.2% (95%, CI 72-90), and 80.0% (95% CI, 69-88), respectively and per-protocol based cure rates of these regimens were 79.2% (95% CI, 68-88%), 83.3% (95%, CI 73-91), and 83.1% (95% CI, 72-91%), respectively. Adverse effects, which included diarrhoea, glossitis or skin rash, were reported by 26.1% of the patients. However, these were mild and did not affect compliance. CONCLUSION: One week PPI/AC regimens for H. pylori infection with smaller proton pump inhibitors and antimicrobial dosages compared to regimens used in Western countries were revealed to provide sufficient cure rate (more than 80% by ITT analysis) with mild adverse effects in the Japanese population.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1999

Paroxetine versus citalopram treatment of pathological crying after brain injury.

Selective serotonin reuptake inhibitors (SSRIs) are the treatment of choice for pathological crying after brain injury, independent of accompanying depression. In a series of 26 consecutive patients with acquired brain damage and episodes of involuntary crying, the efficacy and tolerability of paroxetine and citalopram were compared. The severity of pathological crying or laughing was rated based on clinical interviews with symptom provocation. The first 13 patients were treated with paroxetine and another 13 patients received citalopram in single daily doses of 10 to 40 mg. Rapid onset (within 1-3 days) and highly significant (p < 0.001) improvements of emotionalism were observed after both paroxetine and citalopram. There were no efficacy differences, despite the longer symptom duration in the citalopram group. The only adverse effect after paroxetine was nausea, which was reversible, in two patients, and nausea with vomiting in another two patients, who were switched to citalopram. Citalopram was tolerated without adverse effects.

Adult↗
PubMed1999

LOH and mutational analysis of p53 alleles in mouse urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl) nitrosamine.

In human urinary bladder carcinogenesis, alterations in the p53 tumor suppressor gene are common events. We have previously reported that they are also frequent in invasive urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in NON/Shi mice. To further investigate the significance of the p53 gene status for mouse urinary bladder carcinogenesis, we examined both allele loss and mutational alterations in urinary bladder cancers of (NON/Shi x C3H/He/Shi) F1 hybrid mice exposed to the carcinogen for 12 weeks and then maintained for a further 9 weeks without treatment. An intragenic silent polymorphism within exon 7 of the p53 gene between NON/Shi and C3H/He/Shi mice allows assessment of allele loss of the p53 gene and determination of the parental origin of mutated and/or lost alleles. A tissue microdissection method was employed to obtain carcinoma samples without excessive contamination with normal tissue. Allele losses were detected in one of 14 tumors (7.1%) and nine mutations in eight of 14 (57%) tumors were found in exons 5-8 by polymerase chain reaction-single strand conformation polymorphism followed by DNA direct sequencing analysis. All mutations involved one base substitution with an amino acid change, although the types of base substitution were random. In conclusion, the high incidence of p53 alterations suggests a significant role in the genesis of invasive urinary bladder tumors in BBN-treated mice.

Alleles↗
PubMed1999

Emergence and spread of a new clone of M type 1 group A Streptococcus coincident with the increase in invasive diseases in Japan.

BACKGROUND: In Japan invasive group A streptococcal infections such as sepsis and toxic shock syndrome (TSS) have increased since 1992. As is the case in the United States and Europe, M1 serotype is predominant among the isolates from Japanese patients. METHODS: By restriction enzyme digestion and pulsed field gel electrophoresis, we investigated the whole genomic DNA profiles of 95 M type 1 group A streptococcal strains isolated from patients with serious diseases including sepsis, toxic shock syndrome, necrotizing fasciitis and nonsuppurative complications and with uncomplicated pharyngitis during 1979 through 1996 in Japan. RESULTS: The genome profiles among 8 of 10 isolates from patients with serious diseases in 1979 through 1991 were all the same and were shared by the profiles of the 35 of 48 isolates from patients with uncomplicated pharyngitis in 1982 through 1991. All 18 strains isolated from patients with invasive diseases in 1992 to 1996 had a unique profile, which was shared by the profiles of 18 of 19 isolates from uncomplicated pharyngitis during the same period. This genomic profile was distinct from the predominant or any other profiles before 1992, and it was found to be a new clone. CONCLUSIONS: The emergence and spread of this new clone of M type 1 Streptococcus after 1991 may be associated with the increase in invasive streptococcal infections that occurred during the same period in Japan. Genomic profiles as well as serotypes of streptococcal isolates are important for the epidemiology of clinical relevance in streptococcal diseases.

Child↗
PubMed1999

Promotion by sodium L-ascorbate in rat two-stage urinary bladder carcinogenesis is dependent on the interval of administration.

In our two-stage model of rat urinary bladder carcinogenesis employing N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) as the initiator, sodium L-ascorbate (Na-AsA) exhibits dose-dependent promotion. In the present study, in order to assess the possible reversibility of the promoting effects, we investigated how different administration periods of Na-AsA influence its promoting activity. In experiment 1, rats were treated with 5% Na-AsA for different administration periods with or without withdrawal and injected with 5-bromo-2'-deoxyuridine (BrdU) to allow determination of the cell proliferation status. Replicative DNA synthesis in the urinary bladder epithelium was shown to return to normal after removal of the promoting stimulus. In experiment 2, rats were initially given BBN for 4 weeks and subsequently received 16 weeks of Na-AsA, alternating with basal diet, at intervals of 4, 8 or 16 weeks, within a total 32-week period. The longer the continuous exposure to Na-AsA, the greater the yield of papillomas and carcinomas in the urinary bladder. In experiment 3, Na-AsA was given for 4 or 8 weeks after BBN initiation and the animals were killed at weeks 8 and 12. Both promotion of lesion development and increase of DNA synthesis in the urinary bladder epithelium were dependent on the length of exposure to Na-AsA and the total period of exposure. The results indicate that the promoting effects of Na-AsA in urinary bladder carcinogenesis are reversible to a certain extent after its withdrawal, and the existence of a cumulative exposure time threshold seems likely.

Animals↗
PubMed1999

Profile of urinary bile acids in infants and children: developmental pattern of excretion of unsaturated ketonic bile acids and 7beta-hydroxylated bile acids.

Unusual bile acids, such as unsaturated ketonic and 7beta-hydroxylated bile acids, have been detected in urine early in life. To elucidate the normal profiles of usual and unusual urinary bile acids in the neonatal and pediatric periods, we measured the concentrations of 28 kinds in urine from normal newborns, infants, and children by gas chromatography-mass spectrometry. The mean total bile acid/Cr ratio in 7-d-old infants was significantly higher than in subjects of other age groups (birth, 2-4 mo, 5-7 mo, 11-12 mo, 2-3 y, 9-14 y, and adult) (p < 0.05). Relatively large amounts of unusual bile acids were detected during infancy, especially during the period up to 1 mo of age. At that time, 1beta,3alpha,7alpha,12alpha-tetrahydroxy-5bet a-cholan-24-oic, 7alpha, 12alpha-dihydroxy-3-oxo-5beta-chol-1-en-24-oic, and 7alpha,12alpha-dihydroxy-3-oxo-4-cholen-24-oic acids were predominant among the unusual urinary bile acids present. Moreover, the levels of 3alpha,7beta,12alpha-trihydroxy-5beta-cholan+ ++-24-oic acid increased significantly after 2-4 mo of age. These results indicate that bile acid synthesis and metabolism in the liver of developing infants are significantly different from that occurring in the liver of adults. Significant amounts of urinary isomerized 7beta-hydroxylated bile acids were detected after late infancy, probably because of changes in the intestinal bacterial flora response to a change in nutrition. We describe, for the first time, evidence of the epimerization of the 7alpha-hydroxyl group of cholic acid, which may be unique to human development.

Adolescent↗
PubMed1999

High molecular weight corticotropin measured with immunoradiometric assay in a patient with asymptomatic pituitary corticotropinoma.

A 57-yr-old female with corticotropinoma showing no Cushingoid stigmata is reported. Basal plasma levels of ACTH measured with immunoradiometric assay and beta-endorphin were high, 12.6-15.9 pmol/l and 3.5 pmol/l, respectively. Plasma cortisol level and urinary free cortisol excretion were normal, 303-359 nmol/l and 171-226 nmol/day, respectively. Plasma ACTH markedly increased to 70.5 pmol/l with intravenous administration of 100 microg CRH. Diurnal rhythm of plasma ACTH was seen, but its level in the night was still high. Plasma ACTH suppression with dexamethasone was insufficient. CRH stimulation after dexamethasone suppression increased plasma ACTH level from 4.4 to 13.7 pmol/l. Intravenous administration of 4 microg desmopressin increased plasma ACTH from 15.6 to 19.6 pmol/l. Oral administration of 16 mg lepramide insufficiently decreased plasma ACTH from 7.3 to 5.3 pmol/l. However, plasma cortisol responses in these conditions were normal. Postoperative pathological study revealed subtype 1 corticotropinoma immunohistochemically and electron-microscopically. Postoperative basal plasma ACTH decreased to 3.9 pmol/l, although plasma cortisol did not change. Diurnal rhythm and dexamethasone suppressibility of plasma ACTH became normal. Plasma sample was chromatographed on a Sephadex G-75 column. The elution profile showed two peaks of ACTH, one of which was compatible with 1-39 ACTH and another with higher molecular weight ACTH which was probably secreted from corticotropinoma. Anomaly in processing of proopiomelanocortin was suspected.

Adenoma↗
PubMed1999

Reduction of plasma gonadotropin levels and pituitary tumor size by treatment with bromocriptine in a patient with gonadotropinoma.

A pituitary tumor with suprasellar extension was found by magnetic resonance imaging (MRI) in a male with diabetes mellitus. Endocrine examination revealed high plasma follicle-stimulating hormone (FSH) and alpha-subunit levels, which increased with administration of thyrotropin (TSH)-releasing hormone (TRH). Plasma luteinizing hormone (LH) and testosterone levels were low. Pituitary gonadotropin producing tumor was diagnosed. Because the patient refused surgery, bromocriptine was administered and plasma FSH and alpha-subunit rapidly decreased; on MRI the tumor size was gradually reduced. When pituitary operation is not feasible, bromocriptine is one choice of treatment.

Adenoma↗
PubMed1999

Spontaneous recovery from pathologically confirmed lymphocytic adenohypophysitis with a dramatic reduction of hypophyseal size.

A pituitary mass compressing the optic nerve was revealed by magnetic resonance imaging (MRI) in a 35-year-old woman complaining of visual disturbance in the post-partum period. Responses of plasma gonadotropin and corticotropin-cortisol levels to respective hypothalamic hormones were delayed or blunted, but the response of plasma prolactin to thyrotropin-releasing hormone was exaggerated. Diabetes insipidus was not associated. Biopsy revealed lymphocytic adenohypophysitis, and no hypophysectomy was performed. Only five weeks later, the pituitary mass spontaneously disappeared on MRI. The pituitary function was normalized. Anti-thyroidal and anti-pituitary antibodies were negative throughout the clinical course. Pituitary masses developing during late pregnancy or the post-partum period should be carefully observed.

Adult↗