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Biomedical subjects

Y Hishikawa

Publications and source records attributed to Y Hishikawa.

At least 55 records · Page 3Linked to original sources
PubMed1998

[An introduction to sleep disorders--their concept and diagnostic classification].

Not only physical and mental conditions but also social adaptation of a great number of persons are often disturbed by sleep disorders. For example, unexpected inattention and drowsiness due to different sleep disorders including sleep apnea syndrome, narcolepsy, nocturnal insomnia etc, during car-driving and other working situations may lead to traffic accidents and other disasters. This indicates that sleep disorders are not only important medical but also social problems. Recent progresses in the field of sleep disorders medicine have enabled to distinguish many sleep disorders with different clinical manifestations, pathophysiologies and etiologies. Two kinds of international diagnostic classification of sleep disorders are available at present: ICSD (1990) and ICD-10 (1992). Outlines of these international classifications were introduced and their outstanding points and shortcomings were discussed.

Humans↗
PubMed1998

[Endoscopic findings of esophagitis in concurrent chemo-radiotherapy for lung cancer].

We performed esophageal endoscopy with concurrent chemo-radiotherapy for lung cancer in 19 patients. Endoscopical examination proved that seven patients (36.8%) had esophageal erosion or coating (grade 2), four patients (21.1%) had ulcer or bleeding (grade 3) confined to the radiation field, and only one patient (5.3%) had severe symptoms (WHO grade 3). There was a discrepancy between patients' symptoms and endoscopical findings. Endoscopically proven esophagitis, that is, erosion or coating (grade 2), and ulcer or bleeding (grade 3), was more frequent in the daily low-dose chemotherapy group (5/5) than in the full dose chemotherapy group (5/14) (p < 0.05). One patient with grade 3 endoscopial damage showed less recovery in spite of three months medication. In concurrent radiochemotherapy in which the radiation field includes the esophagus, careful attention should be given to radiation esophagitis, which may be underestimated when assessed on the basis of subjective symptoms alone. Therefore, endoscopy is recommended even if patients have few complaints, and once the esophageal ulcer is proven (grade 3), it should be closely followed up using endoscopy.

Adult↗
PubMed1997

Marked suppression of cortical auditory evoked response shortly before the onset of REM sleep.

In 10 of 12 subjects examined, the amplitude of N300, a component of the cortical auditory evoked potential, was evidently smaller in rapid eye movement (REM) sleep than in non-REM sleep. The start of the reduction associated with the onset of the first episode of REM sleep was examined in these 10 subjects. In five of these, a marked reduction of N300 amplitude occurred 0.5-2.5 min before the appearance of muscle atonia of REM sleep. In two subjects, a similarly marked reduction of the N300 amplitude occurred 0.5-1.0 min before the disappearance of sleep spindles or K-complexes. This suggests that a suppression of the synchronizing mechanism in the cerebrum sometimes occurs briefly prior to the occurrence of other physiological phenomena associated with REM sleep.

Acoustic Stimulation↗
PubMed1997

High sialic acid reactivity of sugar chain structure Lewis-X in patients with mental retardation.

It has been reported that platelet-derived growth factor B-chains homodimer (PDGF-BB) improves learning function of mice, and that sugar chain structure Lewis-X of N-glycosylated glycoprotein promotes PDGF-BB secretion from platelets. Based on these findings, we assumed that learning dysfunction in some patients with mental retardation might be due to abnormality in PDGF-BB metabolism and/or Lewis-X structure. No difference in the reactivity of PDGF-BB and Lewis-X was found between the serum of patients with mental retardation and that of normals. But sialic acid reactivity of the Lewis-X fraction in some patients was remarkably higher than that in other patients and in normals. These findings suggest that sialic acids in the Lewis-X fraction may have a relation to one of the causes of learning dysfunction in these patients.

Adult↗
PubMed1997

Hypnotic and hypothermic action of daytime-administered melatonin.

Six healthy male volunteers (average age = 22.5 years) received orally melatonin (MLT; 3 mg or 9 mg) or placebo at 0930 hours in a randomized, single-blind, cross-over study. Both doses of exogenously administered melatonin (ex-MLT) induced transient, significant suppression of core body temperature (BT) compared to the placebo condition. There was no significant difference in the degree of BT suppression among the two MLT conditions in spite of significantly higher levels of serum MLT with the close of 9 mg, suggesting that there may be a threshold level of ex-MLT inducing the hypothermic action. Daytime administered ex-MLT also induced a significant sleep-inducing effect only in the 9 mg condition, while 3 mg ex-MLT failed to produce statistical significance. These findings suggest that the sleep-inducing action of ex-MLT occurs only at relatively high doses, and this action is probably not due to its BT lowering action. The present study led us to assume that ex-MLT produce its therapeutic effect for circadian rhythm sleep disorders through induction of circadian phase-shifting preceded by an acute, transient hypothermic action rather than light entrainment after setting sleep time by induction of sleep propensity.

Adult↗
PubMed1997

Dopamine releasing response in rat striatum to single and repeated electroconvulsive shock treatment.

1. The effect of electroconvulsive shock (ECS) on extracellular concentration of dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) was examined with the use of in vivo microdialysis in rat striatum. 2. Extracellular concentration of DA was markedly increased up to 183% after single ECS, and that of DOPAC, HVA and 5-HIAA was also significantly increased. The increase after the eighth ECS was attenuated compared to their increase soon after the first ECS. After repeated ECS, baseline concentration of DOPAC, HVA and 5-HIAA was significantly increased, and baseline DA concentration tended to increase. 3. These results suggested that single and repeated ECS activated metabolism of DA and 5-hydroxytryptamine in rat striatum. Activated metabolism of DA may be responsible for the clinical effect of electroconvulsive therapy for parkinsonism.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1997

Recurrent paroxysmal episodes characterized by perceptual alteration in three schizophrenic patients on neuroleptic medication.

A suddenly occurring episode characterized by perceptual alteration (SEPA), mainly of visual and/or auditory modalities, which repeatedly occurred in three schizophrenic patients on long-term neuroleptic medication, is described. Perceptual alteration showed some distinct features that were different from acute symptoms of schizophrenia, and was accompanied by mood changes such as severe anxiety and agitation and, in one of the patients, also by extrapyramidal symptoms. Perceptual alteration, as well as mood changes and extrapyramidal symptoms, responded well to an anticholinergic drug, biperiden. Recent studies have shown that SEPA occurred not only in schizophrenic patients but also in patients on long-term neuroleptic medication for treating other mental disorders. These findings suggest that SEPA is associated with dopaminergic hypoactivity in the brain, which is induced by long-term neuroleptic medication.

Adult↗
PubMed1997

Muscle sympathetic nerve activity during central, mixed and obstructive apnea: are there any differences?

We recorded muscle sympathetic nerve activity (MSNA) from the peroneal nerve during sleep in three OSAS patients who showed three kinds of apnea. During central apneas and central component of mixed apnea, bursts of MSNA appeared in high probability with almost each heart beat. During obstructive apneas and the obstructive component of mixed apneas, bursts of MSNA appeared in a cluster after the end of each inspiratory effort. Burst rate of MSNA during apnea were higher in cental apneas and the central component of mixed apnea than in obstructive apneas and the obstructive component of mixed apneas. These findings indicate that activity in the sympathetic nervous system is enhanced not only in obstructive apnea but also in central and mixed apnea.

Adult↗
PubMed1997

[Radiation therapy for adrenal metastases].

PURPOSE: To evaluate the role of radiation therapy for adrenal metastases. MATERIALS AND METHODS: Fourteen patients, 13 with primary lung carcinoma and one with primary unknown carcinoma, received radiation therapy for adrenal metastases from 1984 to 1995 at the Hyogo Medical Center for Adults. Total dose ranged from 16 Gy to 60 Gy, and fractional dose from 1.6 Gy/ Fr to 3 Gy/Fr. RESULTS: Partial response of the local tumor was recognized in 2 of 7 patients by CT imaging. Pain relief was obtained in 7 of 8 patients. Median survival was 3 months, and 6-month survival was 28.6% in all patients. Among patients in the symptomatic group, who had complaints of pain due to adrenal mass, survival was even worse (12.5% at 6 months). There were no severe complications, but 4 patients (29%) had gastrointestinal symptoms. CONCLUSION: Radiation therapy is useful for the purpose of pain relief in adrenal metastases.

Adrenal Gland Neoplasms↗
PubMed1997

[Rhabdomyolysis following water intoxication in two schizophrenic patients].

We report two cases of self-induced water intoxication with rhabdomyolysis. They had been diagnosed as chronic schizophrenia, and admitted to mental hospitals. The patients were transferred to our emergency room because of sudden loss of consciousness and generalized convulsions. Laboratory findings revealed marked hyponatremia (case 1; 109 mEq/L and case 2; 104 mEq/L). CT scans showed the effacement of interhemispheric and bilateral sylvian fissures and sulci of the cerebral hemisphere due to diffuse brain edema. 10% glycerol and saline were intravenously injected to the patients. They recovered from hyponatremia after excreting a large amount of urine. Their disturbed consciousness recovered to the normal level in parallel with the normalization of their serum sodium concentration. Soon after the normalization of their consciousness level, their serum creatine kinase (CK) was markedly elevated (case 1; 13086 IU/L and case 2; 41832 IU/L), and their serum myoglobin level was also significantly elevated (case 1; 2670 ng/ml and case 2; 1420 ng/ml). A sufficient amount of transfusion was performed for avoiding the acute renal failure. The two patients recovered from rhabdomyolysis without any severe complication. We conclude that brain CT is useful for the diagnosis of brain edema, and monitoring of CK is also important to anticipate renal damage secondary to rhabdomyolysis.

Adult↗
PubMed1997

[Analysis of in-field and marginal relapse in stage I/II non-Hodgkin's lymphoma treated with radiotherapy].

One hundred sixty-three patients with previously untreated stage I/II non-Hodgkin's lymphoma were analyzed as to their in-field and marginal relapse of the irradiated field following treatment with more than 30 Gy of radiotherapy between 1981 and 1995 at Hyogo Medical Center for Adults. Local regrowth in case of partial response was counted as in-field relapse. Complete response was obtained in 94.5% of the cases at the termination of radiotherapy and in 98.8% finally. The ten-year cumulative in-field relapse and marginal relapse rates were 5% and 8.7%, respectively. The cumulative in-field relapse rate (CIFRR) in cases of bulky disease (more than 5 cm in largest diameter of the tumor) was significantly higher than in those of non-bulky disease (26.1% in 8 years vs 2.4% in 10 years, P < 0.01). The radiation dosage delivered (40 Gy = < and 50 Gy > vs 50 Gy < =) a great much difference in cases of bulky disease (23.8% for 8-year CIFRR vs 0% for 1-year CIFRR, respectively), but less difference with non-bulky disease (2.6% vs 2.2%). High LDH and suboptimal dose chemotherapy (three courses and less chemotherapy containing ADM or its derivatives, chemotherapy without ADM or no chemotherapy) had a negative impact on marginal control in aggressive lymphoma. Extended field setting in aggressive lymphoma was not proven to be beneficial in comparison with involved field setting as to marginal field relapse. Thus, it is concluded that (1) higher doses should be given to bulky disease, (2) careful field coverage with enough margin is recommended for aggressive lymphoma with high LDH or treated without optimal dose chemotherapy, and (3) extended field setting is not necessary.

Adolescent↗
PubMed1997

[Radiotherapy for adenocarcinoma of the uterine cervix].

One hundred three patients with adenocarcinoma of the uterine cervix treated with radiotherapy between 1975 and 1992 were evaluated. The results for 24 patients treated with radiotherapy alone were as follows: The overall 5-year survival rates for Stages I + II (N = 12) and III + IV (N = 12) were 52% and 16%, respectively, lower than those for squamous cell carcinoma (stage I: 89%, II: 54%, III: 44%, IV: 19%). The overall response rate was 79.1%, and the recurrence rate was 54.2% (local recurrence: 29.2%, distant metastasis: 33.3%). In Stage I + II patients with an intracavitary irradiation dose of 40 Gy (LDR) or more, there was no local recurrence. In stage III + IV patients, local recurrence was recognized in spite of the high dosage of intracavitary irradiation. The results for 79 patients treated with combined irradiation and operation were as follows: The overall 5-year survival rates for Stages I, II, III and IV were 76%, 60%, 57%, and 0%, respectively. The incidence of lymph node metastasis was 30.4%, and for Stages I, II, III and IV was 26.7%, 34.6%, 28.6%, and 100%, respectively. This showed that adenocarcinoma had a higher incidence of lymph node metastasis after the early stage. The recurrence rate for patients with lymph node metastasis was 75.0%, significantly higher than 25.4% for patients without lymph node metastasis (p < 0.001). To improve prognosis, 40 Gy or more of intracavitary irradiation dose (LDR) and systemic chemotherapy to prevent distant metastasis are recommended for stage I and II cases. For stage III and IV cases, it was thought to be difficult to control local disease with radiation alone. Additional treatment should be used for these cases, i.e. intraarterial infusion, chemotherapy, hyperthermia and so on.

Adenocarcinoma↗
PubMed1996

Effect of bright light exposure on muscle sympathetic nerve activity in human.

To evaluate the effect of bright light on the sympathetic nervous system in human, muscle sympathetic nerve activity (MSNA) was recorded from the peroneal nerve in five healthy subjects. Each subject was exposed to bright light of 5000 lx for 20 min. After the bright light exposure, MSNA became significantly enhanced. The heart rate increased transiently only during the bright light exposure. The blood pressure did not change significantly during and after the bright light exposure. The result is the first direct evidence showing that bright light modulates the activity of the sympathetic nervous system in normal human.

Adult↗
PubMed1996

Thalidomide, a hypnotic with immune modulating properties, increases cataplexy in canine narcolepsy.

Thalidomide is a sedative hypnotic that was widely used in the 1950s but was withdrawn due to its teratogenic properties. The compound has recently been reintroduced as an immune modulating agent. Thalidomide significantly aggravates canine cataplexy, a pathological manifestation of rapid eye movement (RFM) sleep atonia seen in narcolepsy. This compound also increases REM sleep and slow wave sleep in these animals. In vitro receptor binding and enzyme assays demonstrate that thalidomide does not bind to or enzymatically modulate the neurotransmitter systems reported to be involved in the regulation of cataplexy. Thalidomide may therefore affect cataplexy through its immune modulation properties. Further studies on the mechanisms of action of thalidomide should increase our understanding of the pathophysiology of this disabling disorder.

Animals↗
PubMed1996

Platelet-derived growth factor B-chain homodimer suppressing a convulsion of epilepsy model mouse El.

El mouse is a mutant which has epileptic convulsions after tossing-up stimulations and has a hippocampal dysfunction. Platelet-derived growth factor B-chain homodimer has been reported to be a trophic factor of hippocampal neurons. We found that a recombinant PDGF-BB suppressed the convulsions of El mice in a dose-dependent manner. Furthermore, thrombin-treated mice manifested no convulsions, but thrombin receptor activating peptide-treated ones had convulsions. These findings suggest that an abnormality in PDGF-BB release may make El mice susceptible to tonic-clonic convulsions.

Animals↗