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Biomedical subjects

M Satoh

Publications and source records attributed to M Satoh.

At least 91 records · Page 5Linked to original sources
PubMed2001

Inhibition of poly(ADP-ribose) polymerase attenuates cerebral vasospasm after subarachnoid hemorrhage in rabbits.

BACKGROUND AND PURPOSE: Poly(ADP-ribose) polymerase (PARP) is important in modulating inflammation, which has been implicated in cerebral vasospasm after subarachnoid hemorrhage (SAH). We investigated the role of PARP in vasospasm using 3-aminobenzamide (3-AB), a PARP inhibitor, in a rabbit model. METHODS: Twenty-four New Zealand White rabbits were divided into 4 groups: (1) no treatment (control group, n=6); (2) blood injection without pretreatment (SAH-only group, n=6); (3) blood injection with pretreatment by vehicle (SAH+vehicle group, n=6); and (4) blood injection with pretreatment by 3-AB (SAH+3-AB group, n=6). We used the single-hemorrhage model of SAH, injecting autologous arterial blood into the cisterna magna. Angiography was performed before (baseline) and after (day 2) SAH, and the diameter of the basilar artery (BA) was measured. Animals were euthanatized after the second angiogram. After perfusion and fixation, the brains were cut into sections for hematoxylin and eosin and immunohistochemical staining for poly(ADP-ribosyl)ation. RESULTS: In the control group, there were no differences in the BA lumen caliber between baseline and day 2 (96.8+/-10.4%). Cerebral vasospasm in the SAH+3-AB group (88.2+/-6. 2%) was remarkably attenuated in comparison with that in the SAH-only group (64.9+/-8.0%) and the SAH+vehicle group (65.6+/-10. 8%). The BA in the SAH+3-AB group showed less corrugation of the tunica elastica interna than that in the SAH-only and SAH+vehicle groups. Staining for poly(ADP-ribosyl)ation was markedly inhibited in smooth muscle and adventitial cells of the BA in the SAH+3-AB group compared with other groups. CONCLUSIONS: Inhibiting ADP-ribosylation attenuates cerebral vasospasm after SAH in rabbits, and PARP activation may play an important role in the development of cerebral vasospasm.

Animals↗
PubMed2001

Nonchemical elimination of inspiratory motor output via mechanical ventilation in sleep.

In six dogs studied in nonrapid eye movement (NREM) sleep, we found that the frequency, volume, and timing of application of mechanical ventilator breaths had marked and sustained inhibitory effects on diaphragm electromyogram (EMG(di)). Single ventilator breaths of tidal volume (VT) 75-200% of control caused apnea (up to three times eupneic expiratory time [TE]) when applied during the initial 25-65% of expiratory time. When continuous controlled mechanical ventilation (CMV) was applied with ventilator frequency increased as little as 1 cycle/min > eupnea and Pa(CO(2)) and VT maintained at near eupneic control levels, EMG(di) was silenced and triangularis sterni EMG (EMG(ts)) became tonic within 2 to 5 ventilator cycles. On cessation of normocapnic CMV, apnea ensued with TE ranging from 1.2 to five times eupneic TE. The spontaneous VT and EMG(di) determined immediately after these prolonged apneas were also markedly reduced in amplitude. The larger the VT applied during the isocapnic CMV (120-200% of eupnea) and the longer the duration of the CMV (3-90 s), the longer the duration of the postventilator apnea. Significant postventilator apneas and postapneic hypoventilation also occurred even when end-tidal CO(2) pressure (PET(CO(2))) was raised 3-5 mm Hg > eupnea (and 7-10 mm Hg > normal apneic threshold) throughout CMV trials at raised frequency and VT. Our findings demonstrate that the increased frequency of CMV was critical to the elimination of inspiratory motor output and the onset of tonic expiratory muscle activity; furthermore, once EMG(di) was silenced, the tidal volume and duration of the passive mechanical ventilation determined the magnitude of the short-term inhibition of inspiratory motor output after cessation of CMV.

Analysis of Variance↗
PubMed2001

Increased expression of transforming growth factor-beta1 in small airway epithelium from tobacco smokers and patients with chronic obstructive pulmonary disease (COPD).

Tobacco smoke is believed to cause small airway disease and then chronic obstructive pulmonary disease (COPD), but the molecular mechanisms by which small airway obstruction occurs remain unknown. To study the gene expression levels of transforming growth factor (TGF)-beta1, a potent fibrogenic factor, in small airway epithelium from smokers and patients with COPD, we harvested highly pure samples of epithelial cells from small airways under direct vision by using an ultrathin bronchofiberscope BF-2.7T (outer diameter 2.7 mm with a biopsy channel of 0.8 mm in diameter). The expression levels of TGF-beta1 were evaluated by reverse transcription-polymerase chain reaction (RT-PCR). The mRNA levels of TGF-beta1 corrected by beta-actin transcripts were significantly higher in the smoking group and patients with COPD than those in nonsmokers (p < 0.01). Furthermore, among smokers and patients with COPD, TGF-beta1 mRNA levels correlated positively with the extent of smoking history (pack-years) and the degree of small airway obstruction as assessed by measurements of flow-volume curves. Immunocytochemistry of the cells demonstrated more intense stainings for TGF-beta1 in samples from smokers and patients with COPD than from nonsmokers. Spontaneously released immunoreactive TGF-beta1 levels from cultured epithelial cells were more elevated in subjects with a history of smoking and patients with COPD than in nonsmokers. Our study showed a close link between smoking and expression of TGF-beta1 in small airways. Our results also suggested that small airway epithelial cells might be involved in obstructive changes found in smokers and patients with COPD.

Analysis of Variance↗
PubMed2001

Titration emulation: a computer-assisted technique that simplifies the quantification of anti-dsDNA antibodies using the Crithidia luciliae assay.

Titers of anti-double-stranded (ds) DNA antibodies in sera from patients with systemic lupus erythematosus (SLE) using the Crithidia luciliae assay method were compared by conventional titration vs the titration emulation method (ImageTiter) to evaluate whether the latter assay can replace manual titration. Titers by the two methods were identical or within one dilution in 98% (41/42) of samples. A single sample showed a two-dilution difference. Titration emulation showed a tendency to under-estimate the titer of high titer anti-dsDNA samples, although the difference was small. Titration emulation is a suitable alternative to the conventional titration method, offering an accurate and cost-effective approach to quantification of anti-dsDNA antibodies.

Animals↗
PubMed2001

Antagonistic effects of selective alpha1-adrenoceptor antagonists MDL73005EF and tamsulosin and partial agonists clonidine and tizanidine in rat thoracic aorta and rabbit iliac artery.

The antagonistic effects of MDL73005EF and tamsulosin and partial agonists clonidine and tizanidine at rat thoracic aorta and rabbit iliac artery alpha1-adrenoceptors were investigated in this study. Selective alpha1-adrenoceptor antagonists MDL73005EF and tamsulosin dose-dependently shifted the concentration-response curves for noradrenaline to the right. Schild plots of the results obtained from the inhibition by MDL73005EF (pA2 8.30 +/- 0.04) and tamsulosin (pA2 10.51 +/- 0.06) of noradrenaline yielded a straight line with a slope of unity in rat thoracic aorta. The slopes of Schild plots obtained from the inhibition by MDL73005EF and tamsulosin of noradrenaline were significantly different from unity in rabbit iliac artery. Schild plots of the results obtained from the inhibition by clonidine and tizanidine of noradrenaline yielded a straight line with a slope of unity in rat thoracic aorta (pA2 7.08 +/- 0.04 and 7.32 +/- 0.04, respectively). These results suggest that alpha1D-adrenoceptors play a significant role in the alpha1-adrenoceptor-agonist-induced contraction of rat thoracic aorta and rabbit iliac artery, and that clonidine and tizanidine interact with the alpha1D-adrenoceptor subtype as competitive antagonists in rat thoracic aorta.

Adrenergic alpha-Agonists↗
PubMed2001

Synthesis of anacardic acids, 6-[8(Z),11(Z)-pentadecadienyl]salicylic acid and 6-[8(Z),11(Z),14-pentadecatrienyl]salicylic acid.

11-Chloro-3-methoxy-2-undecenal was synthesized from 8-bromooctanol, and an annelation reaction with this aldehyde and ethyl acetoacetate proceeded to give the ethyl 6-(8-chlorooctyl)salicylate. Ethyl 6-(8-chlorooctyl)salicylate was converted to ethyl 6-(7-formylheptyl)-2-methoxybenzoate through the iodide after protection of the phenolic hydroxyl group. Finally, the Wittig reaction with the aldehyde and triphenylphosphonium iodides in the presence of BuLi gave the methoxybenzoates, and then treatments of these methoxybenzoates with BBr3 in CH2Cl2 and 10% NaOH in ethanol gave 6-18(Z),11(Z)-pentadecadienyllsalicylic acid (anacardic acid 3) and 6-[8(Z),11(Z),14-pentadecatrienyl]salicylic acid (anacardic acid 4) which were isolated from plants of the anacardiaceae.

Alkenes↗
PubMed2001

Role of relative myocardial perfusion reserve for evaluating stenosis severity in patients with single-vessel coronary artery disease using.

A statistically significant correlation was observed between the severity of anatomic stenosis and coronary flow reserve in experimental animals. A similar correlation in human coronary artery disease (CAD) was shown using positron emission tomography (PET) and pharmacologic vasodilator stress. The present study tested whether the concept of relative myocardial perfusion reserve (MPR) might be superior to absolute MPR in correlating coronary stenosis determined by quantitative coronary arteriography in patients with single vessel CAD using [13N]ammonia and PET. The study group comprised 21 patients (62 +/-10 years old; 15 men, 6 women) with normal left ventricular function who underwent angioplasty for isolated left anterior descending coronary artery stenosis. Absolute MPR, the ratio of dipyridamole-induced hyperemic blood flow to baseline blood flow by [13N]ammonia PET, and relative MPR, the ratio of MPR in regions supplied by stenosed coronary arteries to MPR in remote regions, were measured before and 3 months after angioplasty. The percent diameter stenosis was also quantified on coronary arteriograms just before the angioplasty and again at 3 months after. The study found that absolute MPR (r=0.755; p<0.0001) and relative MPR (r=0.814; p<0.0001) were inversely and nonlinearly correlated with the percent stenosis on angiography. The fitting curve of the correlation between relative MPR and coronary stenosis on angiography was identical to that observed in animal models. Therefore, relative MPR measured by [13N]ammonia PET more accurately and specifically describes stenosis severity in patients with CAD compared with absolute MPR, probably because of its independence from hemodynamic variations and the effects of coronary risk factors.

Adult↗
PubMed2001

Involvement of beta2-adrenergic and mu-opioid receptors in antinociception produced by intracerebroventricular administration of alpha,beta-methylene-ATP.

The present study examined what kind of receptors are involved in the antinociception produced by intracerebroventricular (i.c.v.) administration of a,beta-methylene-ATP using antagonists at adrenergic, serotonin or opioid receptors. Antinociceptive effect of alpha,beta-methylene-ATP (10 nmol/rat) was significantly attenuated by subcutaneous pretreatment with propranolol and naloxone, but not phentolamine or methysergide, at a dose of 10 mg/kg. I.c.v. pretreatment with propranolol (100 nmol/rat), butoxamine (100 nmol/rat), ICI-I 18,551 (100 nmol/rat) and naloxone (30 nmol/rat) significantly attenuated the antinociceptive effect of alpha,beta-methylene-ATP. However, i.c.v. pretreatment with atenolol (100 nmol/rat), naltrindole (30 nmol/rat) or nor-binaltorphimine (30 nmol/rat) did not show any significant effects. These results suggest that supraspinal beta2-adrenergic and mu-opioid receptors are involved in the antinociceptive effect of i.c.v. administered alpha,beta-methylene-ATP.

Adenosine Triphosphate↗
PubMed2001

Unique place of Kampo (Japanese traditional medicine) in complementary and alternative medicine: a survey of doctors belonging to the regional medical association in Japan.

Although there are various kinds of complementary and alternative medicine (CAM) therapies, it is conjectured that medical doctors consider individual CAM therapies to be heterogeneous in nature. Therefore, to investigate the relationship among Kampo (Japanese traditional medicine) and other CAM, a survey using a structured, self-administered questionnaire was performed for 540 randomly selected doctors of the Kyoto Medical Association (KMA). The results showed that some form of CAM was practiced by 73% of the KMA doctors. The most common CAM practice was Kampo, which corresponded to 96.1% of CAM-practicing doctors. A smaller percentage of doctors practiced other forms of alternative medicine. Kampo was best known by doctors among other CAM therapies. Almost all doctors believed in the effectiveness of Kampo. Doctors who believed in the effectiveness of Kampo tended to believe that other CAM therapies were also effective. Cluster analysis revealed that Kampo was distant from the other CAM. It was concluded that Kampo was most frequently practiced and most believed by doctors in Japan among CAM therapies. Since Kampo was independent of other CAM therapies, Kampo's place in CAM therapies was very unique in Japan.

Adult↗
PubMed2001

8-Hydroxydeoxyguanosine levels in white blood cell DNA and ex vivo oxidation resistance of plasma in smokers.

Oxidative DNA damage in peripheral white blood cell of smokers were estimated in accordance with the levels of 8-Hydroxydeoxyguanosine (8-OHdG) in nuclear DNA and the antioxidant status of these smokers' plasma was investigated in terms of the ex vivo oxidation resistance of plasma. In a survey of 12 smokers (4 women) aged 22 to 48, the mean level of 8-OHdG was 3.79+/-0.65 residue/10(6) dG (mean +/- S.D.) with a range from 2.83 to 4.62 residue/10(6) dG. These measurements showed approximately 1.6-fold inter-individual variations of 8-OHdG level in smokers. A higher level of 8-OHdG was found for smokers whose ex vivo plasma oxidation resistance was weak. Significant association is seen between oxidized bases in white blood cells and plasma oxidation resistance, whereas signs of any association with plasma concentration of alpha-tocopherol, ascorbic acid, bilirubin, and uric acid are weak and sporadic. These findings indicate that apparent heterogeneity exists among smokers in some sort of resistance to the oxidative effects of smoking.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2001

Relationship between toxicity and cadmium accumulation in rats given low amounts of cadmium chloride or cadmium-polluted rice for 22 months.

To clarify toxic effects of long-term oral administration of low dose cadmium (Cd) on the liver and kidney, six groups of female Sprague-Dawley rats were fed a diet containing Cd-polluted rice or CdCl2 at concentrations up to 40 ppm, and killed after 12, 18, and 22 months. With toxicological parameters, including histopathology, there was no evidence of Cd-related hepato-renal toxicity, despite a slight decrease of mean corpuscular volume and mean corpuscular hemoglobin of red blood cells with 40 ppm CdCl2. Dose-dependent accumulation of Cd was observed in the liver and kidneys with peak levels of 130 +/- 42 micrograms/g and 120 +/- 20 micrograms/g, respectively, at 18 months in animals treated with 40 ppm CdCl2. A dose-dependent increase in urinary Cd levels became evident with time. Induction of metallothionein (MT) was also observed in the liver and kidney with a high correlation to the corresponding Cd levels. In the proximal renal tubular epithelia of 40 ppm CdCl2-treated rats at 22 months, prominent accumulation of Cd was observed in secondary lysosomes associated with MT deposits in their exocytotic residual bodies. The results demonstrated that, in contrast to the case with high-dose Cd-administration, renal toxicity is not induced by long-term oral administration of low amounts of Cd, although tissue accumulation does occur. Possible protective mechanisms may be operating.

Animals↗
PubMed2001

Papillary squamous cell carcinoma of the oral mucosa: immunohistochemical comparison with other carcinomas of oral mucosal origin.

Papillary squamous cell carcinoma (PSCC) is a poorly described variant of squamous cell carcinoma, and may be confused with verrucous carcinoma of the head and neck. To add to existing knowledge of this rare tumor, we describe two cases of PSCC arising in the oral mucosa. The lesions were composed of exophytic proliferation of atypical to overtly malignant cells similar to those of conventional squamous cell carcinoma, and invasion into the superficial region of the underlying fibrous tissue was seen in the form of islands and cords of malignant cells. Immunohistochemical assessment of cellular proliferative activity showed a significantly high mean percentage of Ki-67 expression in comparison with verrucous carcinoma, but there was no significant difference of Ki-67 expression among PSCC, conventional squamous cell carcinoma and microinvasive squamous cell carcinoma. These results suggest that the biological behavior of PSCC is analogous to that of SCC.

Aged↗
PubMed2001

[Degradation of thiometon in ethyl acetate].

When performing multiresidue analysis of pesticides, the recovery of thiometon was less than 20% from carrots and eggplants, but about 100% from garlic chives and welsh onions. The recovery of thiometon was found to depend on the lot of ethyl acetate. A 2-year-old lot of ethyl acetate caused degradation of thiometon, but a fresh lot of ethyl acetate did not. Analysis showed that ethyl acetate stored for 2 years contained about 5 microL/mL of acetaldehyde. Thiometon was also degraded by acetone or acetonitrile, when acetaldehyde was added to them, in the same manner as by aged ethyl acetate. The fact that the recovery of thiometon from welsh onions was about 100% indicated that some of the mercaptans in allium vegetables may prevent thiometon degradation. Mercaptans such as L-cysteine and 3-mercaptoproionic acid were confirmed to prevent the degradation of thiometon and disulfoton. These findings show that mercaptans may be useful additives for analyzing thiometon and disulfoton.

Acetates↗
PubMed2001

Heated scallop-shell powder slurry treatment of shredded cabbage.

The main component of scallop-shell powder is calcium carbonate (CaCO3). Through heat treatment, CaCO3 in the shell is converted to CaO, which exhibits antibacterial activity. The disinfecting effect of heated scallop-shell powder on shredded cabbage was investigated for various powder concentrations (0.1 to 1.0 g dm(-3)) and treatment temperatures (10 to 40 degrees C). Scallop-shell powder treatment was found to reduce the aerobic bacteria count in cabbage, with increasing effectiveness at higher powder concentrations and treatment temperatures. Coliforms were completely eliminated within 5 min with as little as 0.1 g dm(-3) powder treatment. During storage at 4 degrees C, aerobic bacterial counts did not increase after powder treatment, whereas counts increased with water-washing or sodium hypochlorite treatment at 200 microg dm(-3). The inactivation pattern of bacterial cells in shredded cabbage involved an accelerated decline followed by an extended tail at powder concentrations of 0.1 and 0.5 g dm(-3). We postulate that a fraction of bacterial cells in the initial population becomes tolerant to the shell powder. A proposed model accurately predicts the reducing bacterial counts on shredded cabbage by scallop-shell powder treatment. The decrease in the L-ascorbic acid content of shredded cabbage was approximately 20 to 30% for scallop-shell powder treatment at 0.1 and 0.5 g dm(-3) (20 degrees C), which is almost identical to that by sodium hypochlorite treatment at 200 micorg dm(-3).

Bacteria, Aerobic↗
PubMed2001

[Perioperative management of life-threatening intra-abdominal bleeding with intra-aortic balloon occlusion catheter].

Intra-thoracic aortic clamping using an intra-aortic balloon occlusion catheter (IABOC) is employed for patients with life-threatening intra-abdominal and/or extra-abdominal bleeding in spite of massive transfusion. For perioperative management, we inserted an IABOC preoperatively into a 59-year-old man with life-threatening intra-abdominal bleeding from an abscess formed around his traumatically injured pancreas. We could perform a safe operation in which bleeding was controlled by intermittently occluding the IABOC and the patient was thus prevented from developing into severe hemorrhagic shock. We experienced a usefulness of IABOC for a patient with life-threatening intra-abdominal bleeding uncontrolled due to intra-abdominal adhesion during the perioperative period. However, organ dysfunctions caused by ischemia and reperfusion following intra-aortic balloon occlusion must be prevented by shortening the occlusion time through use of an intermittent method such as described above.

Anesthesia, General↗
PubMed2001

[Development and assessment of real cardiac motion simulation phantom].

To evaluate cardiac images obtained by multi-slice CT, assessments of the temporal resolution and reconstruction algorithm are essential. For these purposes, we have designed and developed a cardiac motion phantom. Using suitable driver sequences, the phantom allowed for modeling of real left ventricular motion, which was characterized by fast pumping, slow pumping, fast filling and slow filling. Our phantom seems to be useful for use in the fundamental assessments and researches of cardiac CT.

Humans↗
PubMed2001

[The effect of intravenous patient controlled analgesia on activities of daily life and medical expense after thoracotomy].

We investigated the efficacy of postoperative intravenous patient controlled analgesia (i.v.-PCA) combined with continuous epidural analgesia (CEA) after thoracotomy. One hundred and eight patients receiving postoperative CEA were randomly divided into two groups; the i.v.-PCA (+) group who received i.v.-PCA combined with CEA and the i.v.-PCA (-) group who did not receive i.v.-PCA. Pain score (100 mm visual analogue scale; VAS) at 24 h and 48 h, postoperative complications, activities of daily life (ADL), the length of hospital stay and medical expense were compared. The length of hospital stay and medical expense were not significantly different between the two groups. The i.v.-PCA (+) group could recover ADL more quickly and had better analgesic state compared with the i.v.-PCA (-) group. The incidence of postoperative complications was lower in the i.v.-PCA (+) group compared with the i.v.-PCA (-) group. It was concluded that the i.v.-PCA combined with CEA had the desirable effects on postoperative analgesia and recovery of postoperative ADL.

Activities of Daily Living↗