Biomedical subjects

M Mohri

Publications and source records attributed to M Mohri.

At least 37 records · Page 2Linked to original sources

PubMed2001

Sleep patterns during 30-m nitrox simulated saturation dives.

The sleep patterns were examined during the simulated 30-m nitrox saturation dives. The standard polysomnography of 15 divers was recorded for a total of 255 nights, as were patterns of change or consistency in sleep variables. A reduction of total sleep time in accordance with the lengthening of sleep latency and the wake after sleep onset was observed through the latter part of the bottom period to the post-dive period, but the other sleep variables did not show any changes. These findings suggest that decompression and the psychological stress due to being in the closed environment of a hyperbaric chamber for a long time have effects on divers' sleep.

Adult↗

PubMed2001

Significance of retropharyngeal node dissection at radical surgery for carcinoma of the hypopharynx and cervical esophagus.

OBJECTIVES: To clarify the efficacy of dissection of retropharyngeal lymph nodes (RPLNs) in the surgical treatment of carcinoma of the hypopharynx and cervical esophagus. STUDY DESIGN: We started planned dissection of the RPLN during initial radical surgery in patients with squamous cell carcinoma of the hypopharynx or the cervical esophagus in 1988. Until 1997, we performed this procedure as a standard operation in 82 consecutive patients. METHODS: Mortality resulting from RPLN metastasis was compared between 82 patients who underwent RPLN dissection and 69 patients who did not undergo the procedure. RESULTS: Of 82 patients, 16 patients (20%) had positive RPLNs. These patients were at high risk of recurrence unless the node(s) were dissected. Although RPLN dissection did not improve the cumulative 5-year survival rate, it significantly decreased the number of patients who died of RPLN metastasis (chi2 = 3.68, P <.1). Four of the 16 patients who had positive RPLNs survived without any recurrence. CONCLUSION: Bilateral dissection of the RPLN during initial surgery is highly recommended in every surgical case of carcinoma of the hypopharynx and cervical esophagus.

Carcinoma, Squamous Cell↗

PubMed2001

Total occlusion of inferior vena cava in a patient with antiphospholipid antibody syndrome associated with behçet's disease.

Behçet's disease frequently involves the venous system, usually affecting small vessels, but sometimes large vessels such as the vena cava. Antiphospholipid antibody syndrome is associated with an increased incidence of arterial and venous thrombosis. A 29-year-old male with Behçet's disease developed bilateral leg edema secondary to thrombotic occlusion of the inferior vena cava. Laboratory tests revealed positive antiphospholipid antibodies and lupus anticoagulant. Treatment with steroid and warfarin subsequent to intravenous administration of uro-kinase resulted in improvement of symptoms. The association of antiphospholipid antibody syndrome and Behçet's disease may have caused the total thrombotic occlusion of the vena cava in this case.

Adult↗

PubMed2001

[Mechanism for producing a neoglottal fricative [h] in tracheoesophageal speech].

BACKGROUND: Over the past 24 years, we have been performing the tracheoesophageal (TE) fistulization for voice restoration following a total laryngectomy. The principle of this technique is to divert the exhaled air through the TE fistula into the hypopharynx, where the thyropharyngeus muscle forms the retropharyngeal prominence on which the neoglottis is located. In TE speech, the electromyographic (EMG) activity of the thyropharyngeus muscle decreases for voiceless positive production. This neoglottic articulatory adjustment plays an important role in opening the neoglottis. It has been previously reported that the glottis is open for the glottal fricative ([h]) sound produced with laryngeal articulatory adjustment and that turbulence through the glottis produces the [h] sound in laryngeal speech. Of all the voiceless consonants in the Japanese language, [h] is the most difficult to produce in TE speech. This suggests that other adjustments in addition to the neoglottic articulatory adjustment are necessary to produce the [h] sound in TE speech. This study was designed to clarify the mechanism by which the neoglottal fricative ([h]) sound is produced. SUBJECTS AND METHODS: Eight speakers who could pronounce [h] were included in this investigation, a fiber optic examination of the neoglottis, aerodynamic study, and an EMG examination of the thyropharyngeus muscle during the production of words containing voiceless fricative [h] and [s] sounds were performed in each subject. The two groups were classified according to the subject's success or failure in producing words with initial [h] and medial [h] sounds. Out of 80 TE speakers who could not pronounce [h], 4 subjects were selected as the control group. RESULTS: Fibroptic examination revealed a transient neogottal opening during the production of [h] and [s] sounds. The median of the average opening time was 0.26 seconds for initial [h] sounds and 0.19 seconds for medial [h] sounds. No significant difference in opening time was observed for [h] and [s] sounds. The aerodynamic investigation demonstrated a transient increase in supraneoglottal pressure and airflow through the neoglottis and a transient decrease in subneoglottal pressure for [h] production, while no changes were observed in the control group. The EMG study demonstrated that the activity of the thyropharyngeus muscle decreases in cooperation with a transient decrease in subneoglottal pressure only for [h] production. As a result of the transient decrease in subneoglottal pressure, the EMG activity for [h] decreased more strongly than that for [s]. CONCLUSIONS: These findings indicate that both neoglottic adjustment and pulmonary adjustment are required for [h] production in TE speech.

Aged↗

PubMed2001

[Clinical study on the cases in which INH or RFP was discontinued during treatment for pulmonary tuberculosis].

Short course regimens; 2HRZ (E)(S)/4HR (E), 6HRS (E)/3-6HR and 6-9HR have been accepted as a standard chemotherapy (SC) for initial treatment of pulmonary tuberculosis in Japan. We studied the frequency of the treatment completion, the causes of the treatment failure and the outcome of the patients in whom INH or RFP was discontinued within 6 months after starting SC. The subjects included 597 newly diagnosed culture positive pulmonary tuberculosis patients admitted to 16 national hospital in 1996. Results were as follows. 1. In 47 (7.9%) of the 597 patients, either INH (19; 3.2%) or RFP (33; 5.5%) was discontinued. These 47 cases were defined as a SC incompleted group and the other 550 as a SC completed group. 2. The patients in the SC incompleted group were seen more frequently in the ages of 20s (11.9%), 50s (10.9%), 60s (11.7%) or 70s (11.4%). 21 (13.6%) of 154 female patients and 26 (5.9%) of 443 male patients were in the SC incompleted group. 3. The causes of cessation of INH or RFP were drug side effects (33; 5.5%), drug resistance (10; 1.7%) and complications or underlying diseases (8; 1.3%). 4. Fever or eruption (19; 3.2%) and drug induced hepatitis (12; 2.0%) were frequently seen as drug related side effects causing the cessation of INH or RFP. 5. The rate of culture negative conversion of TB bacilli at 6 months after the start of the treatment was 98.9% in the SC completed and 88.9% in the SC incompleted group respectively. In the SC incompleted group, there were three cases continuously positive and two other patients who relapsed and became culture positive again. In these five patients, INH or RFP was discontinued because of drug resistance.

Adolescent↗

PubMed2000

Adrenomedullin receptors in rat cerebral microvessels.

To characterize the sites of action of adrenomedullin (AM) in the cerebral microvasculature, we studied the effect of AM on cyclic AMP (cAMP) level as well as expression of AM and its receptor in the rat cerebral microvessels. The microvessels were prepared from rat cerebral cortex by albumin flotation and glass bead filtration technique. AM and calcitonin gene-related peptide (CGRP) increased cAMP level in the microvessels in a concentration-dependent manner. The effect of AM was more than 100 times more potent than that of CGRP. The accumulation of cAMP by AM was inhibited by AM[22-52], an AM receptor antagonist, but not by CGRP[8-37], a CGRP receptor antagonist, suggesting that AM increased cAMP accumulation by acting on receptors specific to AM. [125I]AM binding to the microvessels was displaced by AM and less potently by AM[22-52]. The displacing potencies of CGRP and CGRP[8-37] were very weak. mRNAs for AM as well as calcitonin-receptor-like receptor and receptor-activity-modifying protein 2 which form a receptor specific to AM, were highly expressed in the microvessels. These results provide biochemical and pharmacological evidence that AM is produced in and acts on the cerebral microvessels in an autocrine/paracrine manner and is involved in regulation of cerebral microcirculation.

Adrenomedullin↗

PubMed2000

alpha(1)-Adrenergic receptor subtypes in rat cerebral microvessels.

To identify alpha(1)-adrenergic receptor subtypes involved in the regulation of cerebral microcirculation, we studied alpha(1)-adrenergic receptor subtypes expressed in the rat cerebral microvessels. The microvessels were prepared from rat cerebral cortex by albumin flotation and glass bead filtration techniques. [(125)I]HEAT binding to the cerebral microvessels was displaced by low concentrations of 5-methylurapidil, a selective antagonist for alpha(1A)-receptors, and modified Scatchard analysis of the data revealed that half of alpha(1)-receptors is alpha(1A)-subtype, and that alpha(1B)- and/or alpha(1D)-receptors are also present. The K(i) value of the high-affinity component for 5-methylurapidil was 3.90+/-1.08 nM, which is comparable with the value obtained in the rat cerebral cortex (2.17+/-0.88 nM). Reverse transcription and polymerase chain reaction experiments showed that mRNAs of alpha(1A)- and alpha(1B)-receptors, but not alpha(1D)-receptors, were expressed in the cerebral microvessels. These results suggest that alpha(1)-receptors involved in the regulation of cerebral microvessel function are alpha(1A)- and alpha(1B)-receptor subtypes.

Adrenergic alpha-Antagonists↗

PubMed2000

Job strain, Type A behavior pattern, and the prevalence of coronary atherosclerosis in Japanese working men.

OBJECTIVE: To examine the relation of type A behavior pattern and job strain to angiographically documented coronary stenosis. METHODS: Subjects were 197 male Japanese patients with a full-time job. A questionnaire-based interview elicited psychosocial and other factors. Type A behavior pattern was measured by 12 questions, and job strain by the method of Karasek. Significant coronary stenosis was defined when a 75% or greater luminal narrowing occurred at one or more major coronary arteries or when a 50% or greater narrowing occurred at the left main artery. Logistic regression analysis was used to calculate odds ratio (OR) and 95% confidence interval (CI) with adjustment for traditional coronary risk factors and job type. RESULTS: Type A behavior pattern was related to a statistically non-significant lower prevalence of the coronary stenosis especially in the absence of job strain (adjusted OR 0.6, 95% CI 0.3-1.2). Job strain was non-significantly associated with a modestly increased prevalence of coronary stenosis (OR 1.7, 95% CI 0.6-5.2). CONCLUSION: These findings suggest that both the behavioral pattern and psychosocial work environment may be related to coronary artery stenosis.

Adult↗

PubMed2000

Relation between green tea consumption and the severity of coronary atherosclerosis among Japanese men and women.

PURPOSE: To examine the relation between green tea consumption and arteriographically determined coronary atherosclerosis. METHODS: Study subjects were 512 patients (302 men and 210 women) aged 30 years or older who underwent coronary arteriography for the first time at four hospitals in Fukuoka City or one hospital in an adjacent city between September 1996 and August 1997. Lifestyle characteristics including green tea consumption were ascertained before arteriography by a questionnaire supported with interview. RESULTS: 117 men (38.7%) and 50 women (23.8%) had significant stenosis of one or more coronary arteries. Green tea consumption tended to be inversely associated with coronary atherosclerosis in men, but not in women. An evident, protective association between green tea and coronary atherosclerosis was observed in a subgroup of 262 men excluding those under dietary or drug treatment for diabetes mellitus. In this subgroup, after adjustment for traditional coronary risk factors and coffee, odds ratios of significant stenosis for consumption of 2-3 cups and 4 or more cups per day were 0.5 (95% confidence interval 0.2-1.2) and 0.4 (0.2-0.9), respectively, as compared with a consumption of one cup per day or less. CONCLUSIONS: The results indicate that green tea may be protective against coronary atherosclerosis at least in men.

Adult↗

PubMed2000

Expression of multidrug resistance-associated protein (MRP) in human gliomas.

Drug resistance is a major clinical problem in the chemotherapy of human gliomas. The multidrug resistance-associated protein (MRP), a membrane transporter related to non-P-glycoprotein multidrug resistance, is overexpressed in some drug-selected cancer cell lines. To investigate whether MRP is involved in the intrinsic drug resistance of human gliomas, surgical specimens of 20 gliomas (11 glioblastomas, 6 anaplastic astrocytomas, and 3 astrocytomas), 3 normal brain specimens, and 4 glioma cell lines (U87MG, U251MG, U373MG, and T98G) were analyzed. The expression of MRP was studied by RT-PCR and immunohistochemistry in the surgical specimens. The MRP expression levels in the cell lines were assessed by the quantitative RT-PCR and Western blot analyses. Sensitivity to adriamycin (ADM), etoposide (VP-16), cisplatin (CDDP), and 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU), were determined by MTT assay, and antisense treatment was evaluated in the cell lines. The expression of MRP was detected in 9 of 11 glioblastomas and 3 of 6 anaplastic astrocytomas. The quantitative analyses of the cell lines revealed that the MRP mRNA and protein levels were increased 4.5-fold in the T98G cells as compared to U87MG. T98G cells showed the highest resistance to all drugs. Western blot analysis revealed that treatment with the antisense oligonucleotide reduced the level of MRP expression to 25% of the sense oligonucleotide treatment in T98G cells. The sensitivity to ADM, VP-16 and CDDP was significantly increased in the antisense-treated cells as compared with the sense-treated cells. These results suggest that the MRP expression may be related to the intrinsic multidrug resistance in human gliomas.

ATP-Binding Cassette Transporters↗

PubMed2000

Intracoronary enalaprilat improves metabolic coronary vasodilation in patients with idiopathic dilated cardiomyopathy.

Coronary flow reserve is reduced in patients with idiopathic dilated cardiomyopathy (DCM). We examined acute effects of intracoronary enalaprilat on metabolic coronary vasodilation during pacing tachycardia in patients. Coronary blood flow (Doppler guidewire) and diameter (quantitative angiography) were measured in seven patients with DCM and seven control subjects. In the DCM group, tachypacing increased coronary blood flow by 37 +/- 22% from the baseline before enalaprilat and by 65 +/- 22% (p < 0.01 vs. before treatment) after enalaprilat (0.5 microg/kg/min for 5 min, i.c.) at comparable double product. Pacing-induced dilation of the epicardial coronary artery also was greater after enalaprilat (p < 0.05). Effects of enalaprilat on coronary blood flow and diameter during pacing tachycardia were abolished by pretreatment with intracoronary administration of the nitric oxide (NO) synthesis inhibitor, N(G)-monomethyl-L-arginine. These beneficial effects of enalaprilat on large and small coronary vasodilation were not observed in control patients. Thus, intracoronary enalaprilat acutely augmented dilator responses of the large and small coronary arteries to pacing tachycardia in patients with DCM, and NO appeared to play an important role in mediating the effects of enalaprilat. These favorable effects of enalaprilat on the coronary circulation may be of clinical significance in patients with heart failure due to nonischemic DCM. Further long-term studies of the effects of angiotensin-converting enzyme inhibition on coronary vasodilation will be needed in this population.

Aged↗

PubMed2000

Saccharomyces cerevisiae sigma 1278b has novel genes of the N-acetyltransferase gene superfamily required for L-proline analogue resistance.

We discovered on the chromosome of Saccharomyces cerevisiae Sigma 1278b novel genes involved in L-proline analogue L-azetidine-2-carboxylic acid resistance which are not present in the standard laboratory strains. The 5.4 kb-DNA fragment was cloned from the genomic library of the L-azetidine-2-carboxylic acid-resistant mutant derived from a cross between S. cerevisiae strains S288C and Sigma 1278b. The nucleotide sequence of a 4.5-kb segment exhibited no identity with the sequence in the genome project involving strain S288C. Deletion analysis indicated that one open reading frame encoding a predicted protein of 229 amino acids is indispensable for L-azetidine-2-carboxylic acid resistance. The protein sequence was found to be a member of the N-acetyltransferase superfamily. Genomic Southern analysis and gene disruption showed that two copies of the novel gene with one amino acid change at position 85 required for L-azetidine-2-carboxylic acid resistance were present on chromosomes X and XIV of Sigma 1278b background strains. When this novel MPR1 or MPR2 gene (sigma 1278b gene for L-proline analogue resistance) was introduced into the other S. cerevisiae strains, all of the recombinants were resistant to L-azetidine-2-carboxylic acid, indicating that both MPR1 and MPR2 are expressed and have a global function in S. cerevisiae.

Amino Acid Sequence↗

PubMed2000

Congenital defects of the vomer.

Six cases of congenital defect of the vomer, a rare nasal anomaly, are reported. All 6 patients visited Kobe University Hospital with other complaints, and the anomaly was incidentally detected. In all cases, the nasal septum showed a defect at the posteroinferior portion that appeared to coincide with the location of the vomer. None of the patients had a past history of nasal trauma, nasal surgery, drug abuse, or infectious disease. This anomaly may be attributable to an embryological disorder based on an immature ossification center of the vomer.

Adult↗

PubMed2000

[Combined valvular and coronary artery surgery].

Between 1990 and 1999, 78 patients underwent combined valvular coronary artery operation. Aortic valve disease was present in 49 patients, mitral valve disease in 23 patients, aortic and mitral valve disease in 6 patients. The average age was 67 years. Twelve patients had had a previous myocardial infarction. The average number of grafts inserted was 1.82 per patients, and the average number of artery grafts inserted was 0.96 per patients. The most number of grafts were placed prior to valve replacement or plasty. And periods of myocardial ischemia were kept at a minimum by coronary perfusion through free grafts. Preoperative mortality was 1.3%. And event fee ratio after operation was 95% (mean follow up 42 month). Therefore the operative risk of combined surgery is, in general, low and the long term results are favorable.

Aged↗

PubMed2000

Experimental kerosene poisoning in goats.

Eighteen young native male and female goats were divided into 3 equal groups. Kerosene was given to Groups 1, 2 and 3 as single doses of 10, 20 or 40 ml/kg bw respectively. Clinical signs In-Group 1 were mild behavioral changes and in Group 2 were mild to moderate bloat, coughing and behavioral changes. None of the goats of Groups 1 and 2 died. Goats of Group 3 had severe signs of poisoning and died within 4 h to 11 d after dosing with clinical signs of severe bloat, frequent coughing, vomiting, and expelling of kerosene from the mouth and nose. Star-gazing, depression, recumbency and dyspnea also occurred. Postmortem changes in Group 3 were gangrenous pneumonia, pleuropneumonia, congestion in brain and kidney, perivascular and perineuronal edema in brain tissue, and renal nephrosis.

Animals↗

PubMed1999

The effect of graft perfusion with warm blood cardioplegia for cadaver heart transplantation.

This study was designed to verify the effect of reperfusion of donor hearts in a perfusion apparatus after 60 min of global ischemia prior to heart transplantation. Thirteen dogs were exsanguinated from the femoral artery and cardiac arrest was achieved. The hearts were left in situ at room temperature (25 degrees C) for 60 min. In group A (n = 7), the hearts were excised and reperfused 60 min after cardiac arrest in the perfusion apparatus with substrate-enriched warm blood cardioplegia (WBCP) containing a hydroxyl radical scavenger, EPC, followed by 45 min of blood perfusion. Next, the hearts were preserved in cold (4 degrees C) University of Wisconsin (UW) solution. In group B (n = 6), the hearts were perfused with cold (4 degrees C) St. Thomas' solution 60 min after cardiac arrest and preserved in cold UW solution. Thereafter, all hearts in both groups were transplanted orthotopically to recipient dogs. In group A, 6 of 7 dogs were weaned from cardiopulmonary bypass (CPB). In group B, only 2 of 6 dogs were weaned from CPB. Moreover, 3 of the 6 hearts in group B did not start beating after transplantation (stone heart). This study suggested reperfusion of the donor heart in the perfusion apparatus with WBCP to be a beneficial preconditioning method when utilizing 60-min arrested hearts for transplantation.

Animals↗

PubMed1999

Sleep patterns during 20-m nitrox saturation dives.

The sleep patterns were examined through three simulated 20-m nitrox saturation dives. The standard polysomnography of 12 divers was recorded respectively for a total of 204 nights, as were patterns of change or consistency in sleep variables. For the 11 divers in their 20s and 30s there was nothing unusual about their sleep variables. However, a reduction of total sleep time in accordance with the lengthening of sleep latency was observed. This was recognized from the latter part of the bottom period to the postdive period. This tendency was notable for the diver in his 50s. These findings suggest that the decompression environment and the psychological stress of the long-term closed environment of a hyperbaric chamber have effects on divers' sleep.

Adult↗

PubMed1999

Esophageal contractility synchronous with expiration.

On the basis of our previous finding that the cervical esophagus was closed during tracheoesophageal phonation, we postulated that the muscle of the cervical esophagus actually contracted during expiration and speculated on its possible regulation by the recurrent laryngeal nerve. Electromyography of the esophageal musculature and fluoroscopy of the esophagus were performed in laryngectomees to demonstrate whether the esophagus contracted during expiration or not. Electromyography, performed in 2 subjects, revealed a burst of discharges synchronous with expiration. Fluoroscopy during tracheoesophageal phonation was performed in 13 subjects to investigate the influence of resection of the esophageal branch of the recurrent nerve on esophageal motor activity. Among 13 subjects, 4 subjects who underwent paratracheal dissection (PTD) at the time of laryngectomy showed a lower superior limit of esophageal closure than did the 9 subjects without PTD, indicating that the cervical esophagus in PTD loses its contractility with the sacrifice of the esophageal branch of the recurrent nerve. We concluded that the cervical esophagus is closed by muscle contraction synchronous with expiration, preventing air entry into the stomach during deep expiration or phonation, and that the esophageal branch of the recurrent nerve is involved.

Electromyography↗