Search PubMed⌕ Search

Biomedical subjects

Y Satoh

Publications and source records attributed to Y Satoh.

At least 217 records · Page 12Linked to original sources

[Hippocampal hypoperfusion underlying dementia due to chronic toluene intoxication].

To elucidate the pathophysiology underlying the dementia due to chronic intoxication of toluene, a positron emission tomography was carried out in a 24-year-old right-handed man who had been sniffing thinner which contains toluene for 6 years. In addition to the cerebellar ataxia and pyramidal signs, this patient exhibited a mental deterioration including recent memory disturbance: verbal IQ was 52, performance IQ was 52 and total score was 51 on WAIS-R. MRI revealed a mild diffuse cortical atrophy, symmetrical hyperintensity lesions in the corticospinal tracts including corona radiata posterior limb of the internal capsule and ventral part of the pons, and hypointensity lesions in the both thalami on T2-weighted images, whereas the changes in the deep white matter was relatively mild on T2-weighted images. In PET, both cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were diffusely decreased bilaterally, and specifically in both hippocampi, they were reduced as low as 61% of the normal values as obtained from 12 young normal volunteers. Additionally, in the frontal cortex, CBF and CMRO2 were 60% and 71% of the normal values, respectively. Although the dementia due to chronic toluene intoxication has been assumed to be closely related to the degree of the cerebral white matter lesions based on the MR findings, the present results suggest that the mental deterioration including recent memory disturbance seen in the early stage of chronic toluene intoxication is associated with the hypoperfusion and hypometabolism in the hippocampus and frontal limbic system.

Adult↗

[Pharmacokinetic and clinical studies with cefluprenam in the pediatric field. Pediatric Study Group of Gefluprenam].

Evaluation of efficacy and safety of cefluprenam (code number: E1077, abbreviation: CFLP), a newly developed injectable cephem antibiotics was conducted on adult patients with various infections, and followed by the study group organized from 39 institutions in pediatric field, as the drug showed no toxicity problems in suckling animals. Informed consents from legal representatives were obtained prior to the study. 1. Clinical efficacy. Two-hundred eighty one cases were included for analysis of clinical efficacy after 40 cases of exclusion or drop-out were subtracted from a total of 321 cases. However, the cumulative number of cases evaluable for analysis was considered to be 289, because 8 cases that had 2 different diseases at the same time were counted in each category of disease. In the cases in which causative organisms were identified (group A), 148 of 154 cases were rated as good or excellent, with an efficacy rate of 96.1%. As for clinical efficacies by disease, efficacy rates were 6/6 for purulent meningitis, 4/5 for sepsis, 95.7% (62/65) for pneumonia, 100.0% (29/29) for urinary tract infections, and 94.1% (16/17) for skin and soft tissue infections. The rate of excellent responses among excellent and good responses was 73.6% (109/148), showing a higher value than any of recent injectable beta-lactams. On 32 cases with S. pneumoniae infection, the efficacy rate of CFLP was 100.0%. In the cases where causative organisms were not identified (group B), 128 of 135 cases were rated as good or excellent, with an efficacy rate of 94.8%. In the all cases including both the group A and the group B, the efficacy rate was 95.2% (276/289) and the rate of excellent responses among excellent and good response was 70.7% (195/276). Against severe infections, CFLP exhibited excellent clinical efficacy, showing an efficacy rate of 8/8 for meningitis, 3/5 for sepsis and 100.0% (22/22) for severe pneumonia. As for bacteriological responses, eradication rates were 95.2% (177/186) in total. Against Gram-positive cocci, the eradication rate was 92.7% (76/82), with eradication rates of 94.3% (33/35) for Staphylococcus aureus, and 93.3% (28/30) for Streptococcus pneumoniae. Against Gram-negative rods, the eradication rate was 97.1% (101/104), and eradication rates were 100.0% (22/22) for Escherichia coli, 97.5% (39/40) for Haemophilus influenzae and 100.0% (19/19) for Molaxella catarrhalis. In cases in which more than 3 days of treatment with previous chemotherapy resulted in no response, the efficacy rate of CFLP was 94.2% (98/104), rated excellent in 68 cases and good in 30 cases. In these cases, the eradication rate was 98.1% (52/53). 2. Pharmacokinetics. CFLP was intravenously administerrd to 12 subjects at doses of 20 to 40 mg (potency)/kg. In 9 subjects aged more than 12 months, maximum serum levels (Cmax), T 1/2 beta and AUC of CFLP were 155.3 +/- 9.8 micrograms/ml, 1.43 +/- 0.18 hours and 111.7 +/- 15.0 micrograms.hr/ml, respectively, when a dose of 20 mg (potency)/kg was used. In 2 subjects aged not more than 12 months, the mean Cmax, T 1/2 beta and AUC were 153 micrograms/ml, 1.6 hour and 81 micrograms.hr/ml, respectively, at a dose of 20 mg(potency)/kg. The mean Cmax, T 1/2 beta and AUC were 332 micrograms/ml, 0.93 hours and 157.3 micrograms.hr/ml, respectively, in 1 subject at a dose of 40 mg (potency)/kg. In 10 subjects dosed 20 mg (potency)/kg, urinary levels were 2413 +/- 512, 1471 +/- 524, and 470 +/- 115 micrograms/ml in 0-2, 2-4, and 4-6 hours after dosing, respectively, showing a cumulative urinary excretion rate of 61.4 +/- 6.3%. In 1 subject dosed 40 mg (potency)/kg, urinary levels were 5700 and 4770 micrograms/ml in 0-2 p3d 2-4 hours after dosing, respectively, showing a cumulative urinary excretion rate of 42.1%. Cerebrospinal fluid concentrations of CFLP, on 10 subjects with purulent meningitis dosed 40-103 mg (potency)/kg were 3.2-32.9 micrograms/ml at 0.5-2 hours after administration within 4 days after the onset of

Bacteria↗

Interferon potentiates antiproliferative activity of CPT-11 against human colon cancer xenografts.

We studied the antiproliferative effect of recombinant human interferon-alpha/beta/gamma (rHuIFN-alpha/beta/gamma) and CPT-11 against human colon cancer xenografts in nude mice. CPT-11 (25 mg/kg) alone exhibited significant antiproliferative effects. Although rHuIFN-alpha/beta/gamma alone did not show antiproliferative activity, it markedly enhanced the antiproliferative activity of CPT-11. rHuIFN-alpha/beta/gamma significantly increased in the population of cells in the S-phase. rHuIFN-alpha/beta/gamma progressed cell cycle in the S-phase under the existence of CPT-11, which exhibited no effect on cell cycle progression. Because CPT-11 is known to exhibit antiproliferative effect on S-phase cells, IFNs, especially rHuIFN-alpha and beta, can enhance the antiproliferative effect of CPT-11 mediated by cell accumulation in the S-phase.

Animals↗

Effect of glimepiride (HOE 490) on insulin receptors of skeletal muscles from genetically diabetic KK-Ay mouse.

A new sulfonylurea, glimepiride (HOE 490), has been developed for the glycemic control in non-insulin-dependent diabetes mellitus. We examined the effect of glimepiride on glucose and insulin levels in KK-Ay mice, an animal model of non-insulin-dependent diabetes mellitus, which is characterized by hyperglycemia and hyperinsulinemia. Administration of glimepiride (0.5 mg/kg/day) for 8 weeks to KK-Ay mice resulted in decrease in glucose (297 +/- 36 to 250 +/- 51 mg/dl) and insulin (76 +/- 14 to 41 +/- 14 microU/ml) levels. To clarify the mechanism of the agent, we examined the effect of this new drug on insulin receptors in the skeletal muscles. There was no difference in insulin binding to the receptors from both glimepiride-treated and -untreated KK-Ay mice muscles. The insulin-stimulated autophosphorylation of insulin receptors from KK-Ay mice was decreased compared to that from normal mice (5 +/- 1 vs. 39 +/- 13% over basal). Glimepiride did not ameliorate impaired insulin-stimulated insulin receptor autophosphorylation. To determine the effect of glimepiride on post-insulin receptor signaling pathway, we measured 2-[3H]glycerol incorporation into diacylglycerol in the cultured rat fibroblast cell line overexpressing human insulin receptors. Glimepiride (100 microM) as well as insulin (10 nM) significantly stimulated diacylglycerol production. These results suggest that glimepiride has a potent extrapancreatic effect on glucose metabolism and may directly stimulate glucose transport activity through phospholipid signaling pathway, but not through insulin receptor kinase signaling pathway.

Animals↗

Lipid secretory mechanisms in the mammalian harderian gland.

The mammalian Harderian glands are lipid-secreting glands. In an unstimulated condition, the glandular cells frequently exocytose the lipid materials; however, no intracellular calcium ion ([Ca2+]c) changes are detectable. Cholinergic (muscarinic) secretagogues induce secretory activity and increase of [Ca2+]c. A G-protein activator, sodium fluoride, enhances the secretory activity and increase of [Ca2+]c. Removal of extracellular calcium ions inhibits the secretion enhanced by cholinergic stimulation. Under pharmacologic stimulation, glandular cells may show an apocrine-like secretory pattern. Cholinergic stimulation also induces contraction of the myoepithelial cells covering glandular end pieces; however, the reduction in volume of glandular end pieces is not prominent. Catecholamines have no effect on the release of lipid materials. These results indicate the involvement of G-proteins linking with muscarinic receptors and Ca2+ dynamics (increase of [Ca2+]c and Ca2+ influx) in lipid secretion by glandular cells and in contraction of myoepithelial cells of mammalian Harderian glands. However, the increase of [Ca2+]c in Harderian glands was less when compared with other cells--for instance, those which secrete protein.

Animals↗

Urinary basic fetoprotein in the diagnosis and follow-up of patients with urothelial carcinoma.

BACKGROUND: Urothelial carcinoma is one of the most common malignant neoplasms of the urinary tract and is characterized by a high local recurrence rate. However, no specific and reliable tumor marker has been identified for the diagnosis and follow-up of patients with urothelial carcinoma. METHODS: Urinary basic fetoprotein (U-BFP) levels were measured by enzyme immunoassay in 119 patients with urothelial carcinoma, 64 patients with other urologic malignancies, 144 patients with benign diseases, and 166 healthy individuals to evaluate it clinical efficacy as a marker of urothelial carcinoma. The histologic logic localization of BFP was also studied. A cutoff value was set at 14 ng/mL based on the maximum diagnostic efficiency. RESULTS: The specificity and sensitivity of U-BEP for urothelial carcinoma was 91.7% and 58%, respectively. THe U-BFP positive rate increased significantly with the histologic grade. The U-BFP positive rate was higher in both Tis and T2-4 than in Ta, 1 disease. The U-BFP level exceeded the cutoff value before curative therapy in 32 patients; U-BFP was normalized in 97% of these patients within 2 weeks after therapy. There was a total of 11 recurrences and the U-BFP level returned to abnormally high levels in all instances. Histologic localization of U-BFP was demonstrated in the cytoplasm of the tumor cells in 80% of the patients. CONCLUSION: Based on these results, U-BFP is a potential tumor maker of urothelial carcinoma. In particular, the test could be used to monitor patients whose U-BFP value is positive before therapy.

Adolescent↗

Mitochondrial DNA 3394 mutation in the NADH dehydrogenase subunit 1 associated with non-insulin-dependent diabetes mellitus.

Mitochondrial DNA (mtDNA) mutation is associated with a subtype of non-insulin-dependent diabetes mellitus (NIDDM). We identified two homoplasmic mtDNA mutations at the positions of 3394 (T-C) and 3423 (G-T) in a NIDDM patient with clinical features of mitochondrial encephalopathy. The mtDNA 3394T-C mutation changed a conserved tyrosine to a histidine in NADH dehydrogenase subunit 1. The frequency of mtDNA 3994 T-C mutation was determined with Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) in general NIDDM patients and nondiabetic control subjects. The mutation was seen in 4.9% of NIDDM patients and 1.3% of nondiabetic controls. It is indicated that the mtDNA 3394 T-C mutation is associated with NIDDM in Japan.

Base Sequence↗

Correlation of EEG activities between slow-wave sleep and wakefulness in patients with supra-tentorial stroke.

Using topographic EEG mapping, we studied the relationships between delta activity during slow-wave sleep (SWS) and the background EEG activity during wakefulness, in 11 normal subjects and 35 stroke patients with unilateral supra-tentorial lesions. Delta-1 power during SWS showed a significant positive correlation with alpha-1 power during wakefulness, in both hemispheres. Delta-1 and delta-2 power during SWS correlated positively not only with alpha-2 power, but also with delta-1 and delta-2 power during wakefulness in the affected hemisphere. these figures indicate that the amount of delta activity during SWS can be associated with that of alpha activity during wakefulness. A close negative correlation was observed between delta power during SWS and the age of the subjects in the patient group. The Barthel index showed no significant correlation with delta-1 or delta-2 power in either hemisphere in patient group. Our results suggest that delta activity during SWS may be associated with dysfunction of the cerebral cortex in stroke patients as well as in normal aged subjects.

Adult↗

Scalp topography of SEP late components in patients with supra-tentorial lesions.

Somatosensory evoked potentials (SEP) to simultaneous bilateral median nerve stimulation were recorded in 7 patients with unilateral brain lesions, 8 patients with degenerative dementia, and 5 normal volunteers. Right-left amplitude difference was compared from serial topographic images and the amplitude was compared at homologous electrodes. In patients with unilateral lesions, the amplitude from the frontopolar, frontal, anterior-temporal, and/or occipital electrodes was smaller on the affected side at 240 and 360 msec, regardless of whether the subjects showed sensory deficit or not. No significant laterality was seen in the primary sensorimotor areas. Distribution obtained from the patients with degenerative dementia was quite symmetrical. A significant right-left amplitude difference was seen at the anterior temporal site at 180 and 240 msec in normal controls, although an almost symmetrical distribution was obtained on the topographic images. The late components of SEP are not associated with the primary somatosensory function, but possibly with other cortical pathways.

Aged↗

Secretagogue-induced apocrine secretion in the Harderian gland of the rat.

Harderian glands of male albino rats were stimulated with secretagogues and examined by transmission and scanning electron microscopy for the purpose of studying the apocrine secretory mechanism. Rats in the control group were perfused with standard HEPES-buffered Ringer's solution. Their glandular endpieces showed wide lumina that contained few secretory materials; spontaneous exocytosis was sometimes observed. However, there were no features suggestive of an apocrine secretory mechanism or myoepithelial cell contractions. After stimulation with NaF+AlCl3 or carbachol in HEPES-buffered Ringer's solution, the rats shed "bloody tears" and the glandular lumina were jammed with apical protrusions, cytoplasmic material and secretory products. The basal surface of the glandular cells showed bulging caused by myoepithelial cell contraction. Perfusion with HEPES-buffered Ringer's solution containing papaverine inhibited secretagogue-induced myoepithelial cell contraction but not the enhanced secretory activities of the glandular cells. The present results demonstrate that the Harderian gland of the rat can release secretory material not only by exocytosis, but also by an apocrine mechanism under stimulating conditions, and that myoepithelial cell contraction may not be involved in causing apical protrusion in the glandular cells.

Aluminum Chloride↗

Expression of BCL-2 gene product in embryonal tumors of the central nervous system.

BACKGROUND: The expression of bcl-2 is associated with suppression of programmed cell death and prolonged cell survival. Recently, immunoreactivity to the bcl-2 gene product has been reported not only in a variety of embryonal and adult nonhematopoietic tissues, but also in neuroblastoma. However, the study of bcl-2 expression has not been performed in brain tumors. METHODS: In this study, we examined the incidence and significance of bcl-2 expression in 25 cases of embryonal tumors of the central nervous system, including medulloblastoma, neuroblastoma, ependymoblastoma, and PNET (primitive neuroectodermal tumor), which has the possibility of neuronal differentiation. RESULTS: The results demonstrated that 13 tumors (52%) positive for bcl-2 belonged to early differentiated and neuronal types, and 7 negative tumors (28.0%) mostly belonged to undifferentiated type. CONCLUSIONS: These results have led us to speculate on the possibility that tumor cells begin expressing bcl-2 along with their neuronal differentiation from primitive cells.

Adolescent↗

Effect of manidipine and delapril on insulin sensitivity in type 2 diabetic patients with essential hypertension.

The open trial was designed to evaluate the effects of long-term antihypertensive treatment with the calcium-channel blocker, manidipine and the angiotensin converting enzyme (ACE) inhibitor, delapril on insulin sensitivity in Japanese non-insulin dependent diabetes mellitus (NIDDM) patients with essential hypertension. We measured the insulin sensitivity index (SI) and the glucose-effectiveness (SG) by the use of Bergman's minimal model method in 18 hypertensive NIDDM patients before and after administration of manidipine (group A) or delapril (group B) for 3 months. Manidipine treatment for 3 months significantly improved SI in group A from 3.35 +/- 0.61 (x 10(-4) min-1 microU-1 ml-1) to 4.70 +/- 1.34 (P < 0.05). Delapril treatment for 3 months also significantly improved SI in group B from 3.56 +/- 1.04 to 5.00 +/- 0.87 (P < 0.05). Manidipine significantly improved SG in group A from 1.60 +/- 0.64 (x 10(-2) min) to 2.19 +/- 0.38 (P < 0.05). Delapril treatment also significantly improved SG in the group B from 1.41 +/- 0.56 to 1.91 +/- 0.35 (P < 0.05). Manidipine and delapril did not affect urinary C-peptide excretion for 24 h in the hypertensive NIDDM patients. Treatment with manidipine or delapril significantly reduced systolic and diastolic blood pressures in the hypertensive NIDDM patients. There were no differences between plasma glucose, serum total triglycerides, and cholesterol or lipoprotein cholesterol fractions, heart rate and body weight after 3 months on manidipine or delapril. This study confirmed the improving effects on SI and SG by long-term treatment with manidipine or delapril in the hypertensive NIDDM patients.

Antihypertensive Agents↗

Microwave ablation of the adrenal gland: experimental study and clinical application.

OBJECTIVE: To evaluate the heating effect of microwave irradiation on the dog adrenal gland and to assess the clinical feasibility of microwave ablation of adrenal tumours. MATERIALS AND METHODS: The thermal distribution and histology were evaluated after dog adrenal glands were irradiated at different intensities with microwaves. Irradiation at 70 W for 30 s was also performed after laparotomy, on the adrenal tumour of a patient with primary aldosteronism. RESULTS: Microwave irradiation at 70 W for 30 s provided a sufficiently high temperature to produce coagulation within a 5 mm radius of the microwave electrode. The adrenal tumor in the patient with primary aldosteronism was coagulated successfully by this dose of microwave irradiation. CONCLUSION: Microwave ablation of the adrenal gland may be clinically applicable in the treatment of adrenal tumours.

Adrenal Glands↗

Role of three chitin synthase genes in the growth of Candida albicans.

The CHS2 and CHS3 genes of Candida albicans were disrupted. The double disruptant was still viable. Assessment of chitin and of calcofluor white resistance shows that CHS1 is responsible for septum formation and CHS3 is responsible for overall chitin synthesis otherwise. There were only small differences in virulence to immunocompromised mice of homozygous chs2 delta amd chs3 delta null mutants.

Animals↗

Effects of a thromboxane synthase inhibitor (CS-518) on the eosinophil-dependent late asthmatic response and airway hyperresponsiveness in guinea pigs.

The effects of CS-518, a thromboxane A2 synthase inhibitor, on antigen-induced dual bronchial responses, airway hyperresponsiveness (AHR) and airway eosinophilia were investigated in an experimental guinea pig model of the late asthmatic response. Oral CS-518 (1 and 10 mg/kg) inhibited immediate and late asthmatic responses dose-dependently. It also inhibited AHR and eosinophil accumulation after antigen challenge. Therefore, thromboxane A2 is possibly involved in development of the late asthmatic response and AHR, and CS-518 was inferred to inhibit these via inhibition of eosinophil accumulation and thromboxane production.

Animals↗

Relationship between airway eosinophilia and airway hyperresponsiveness in a late asthmatic model of guinea pigs.

To elucidate the mechanism of development of asthma, we tried to develop a model which elicited a late asthmatic response by a combination of systemic and inhaled sensitization with ovalbumin in guinea pigs. Eighty-seven percent of animals elicited both an immediate and late asthmatic response after the third antigen inhalation. Airway eosinophilia and airway hyperresponsiveness (AHR) induced after the third challenge were more severe than those after the first challenge. There was a good correlation between airway eosinophilia and AHR in this model under experimental modulation of the number of eosinophils, such as by interleukin 5 or antieosinophil antibody injection. These results demonstrate that eosinophils play an important role in the development of late asthmatic response and AHR.

Animals↗