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Biomedical subjects

T Kanbayashi

Publications and source records attributed to T Kanbayashi.

At least 19 recordsLinked to original sources
PubMed2003

CSF hypocretin levels in Guillain-Barré syndrome and other inflammatory neuropathies.

CSF hypocretin-1 was measured in 28 Guillain-Barré syndrome (GBS), 12 Miller-Fisher syndrome, 12 chronic inflammatory demyelinating polyneuropathy (CIDP), and 48 control subjects. Seven GBS subjects had undetectably low hypocretin-1 levels (<100 pg/mL). Hypocretin-1 levels were moderately reduced in an additional 11 GBS, 5 Miller-Fisher syndrome, and 1 CIDP subject. Low levels in GBS occurred early in the disease and were associated with upper CNS level abnormalities.

Adolescent↗
PubMed2003

Narcolepsy in a hypocretin/orexin-deficient chihuahua.

A two-year-old male chihuahua suffered attacks of muscle weakness and immobility, although it had no family history of paroxysmal attacks. No neurological or blood biochemical abnormalities were recorded when it was first examined. The attacks were typically elicited by stimulation, such as feeding, and a case of sporadic narcolepsy-cataplexy was therefore suspected. Treatment orally three times a day with 1 mg/kg imipramine, was effective in reducing the attacks. The concentration of hypocretin-1/orexin A in the dog's cerebrospinal fluid was less than 80 pg/ml (22.5 pmol/litre), compared with normal canine levels of 250 to 350 pg/ml (70.0 to 98.3 pmol/litre), supporting a diagnosis of hypocretin-deficient narcolepsy.

Adrenergic Uptake Inhibitors↗
PubMed2003

CSF hypocretin measures in patients with obstructive sleep apnea.

The majority of patients with narcolepsy-cataplexy were reported to have very low cerebrospinal fluid (CSF) hypocretin-1 (orexin-A) levels. The hypocretin-1 levels of secondary excessive daytime sleepiness (EDS) disorders are not known. In this study, we found that CSF hypocretin levels in the patients with obstructive sleep apnea syndrome were within the control range. The low hypocretin levels seem to reflect only the presence of cataplexy and DR2 positive in narcoleptics but not EDS itself.

Adult↗
PubMed2002

Undetectable levels of CSF hypocretin-1 (orexin-A) in two prepubertal boys with narcolepsy.

We report on two prepubertal narcoleptic boys with undetectable levels of hypocretin-1 (orexin-A) in their cerebrospinal fluid (CSF). The disease onset times were 6 and 8 years, and CSF was collected 8 and 20 months after the onset, respectively. The initial symptoms were excessive daytime sleepiness, cataplexy and disrupted nocturnal sleep. Both subjects are DRB1*1501 and DQB1*0602 positive. The measurement of CSF hypocretin-1 is valuable for the decisive diagnosis of narcolepsy and for selecting the type of treatment in prepubertal children. Our results suggest that a significant degree of hypocretin deficiency is already present at the disease onset.

Age Factors↗
PubMed2001

Hypersomnia due to acute disseminated encephalomyelitis in a 5-year-old girl.

A 5-year-old girl suffering from hypersomnia due to acute disseminated encephalomyelitis (ADEM) is reported. Brain CT revealed a large low-density lesion involving the lentiform nucleus, posterior limb of the internal capsule, thalamus, posterior hypothalamus and midbrain in the left side. She was treated with intravenous dexamethazone. After the initial dose of dexamethazone, hypersomnia was dramatically and rapidly improved. A later brain CT study disclosed that the lesion in the brain disappeared. The brain lesion in this case involved the waking center in the brain, which was described by Von Economo. We concluded that hypersomnia in this case was due to ADEM involving the neural mechanism for maintaing wakefulness, probably in the thalamus and posterior hypothalamus. Repeat all night polysomnograpy in this case disclosed prolonged total sleep time and increased amount of stage 3-4 sleep in the hypersomniac state.

Journal Article↗
PubMed2001

The effects of oral melatonin on the autonomic function in healthy subjects.

We investigated the influence of melatonin on the human autonomic functions by measuring muscle sympathetic nerve activity (MSNA). Five healthy male volunteers took 3 mg of melatonin, and their plasma melatonin concentration, blood pressure, heart rate, and burst rate of MSNA were then recorded. The peak level of melatonin concentration showed a marked interindividual variation. Blood pressure was reduced significantly, while heart rate and burst rate of MSNA did not change significantly. These results indicate that melatonin has a hypotensive effect on blood pressure, and the central cardiovascular regulatory mechanism such as lowering of the baroreflex setpoint would be involved in the effect.

Administration, Oral↗
PubMed2000

Implication of dopaminergic mechanisms in the wake-promoting effects of amphetamine: a study of D- and L-derivatives in canine narcolepsy.

Using a canine model of narcolepsy and selective DA and NE uptake inhibitors, we have recently shown that DA uptake inhibition promotes wakefulness, while NE uptake inhibition inhibits rapid eye movement sleep and cataplexy. In order to further delineate the respective roles of the dopaminergic and noradrenergic systems in the pharmacological control of symptoms of narcolepsy, we compared the potency of amphetamine isomers (D- and L-amphetamines) and a derivative (L-methamphetamine) on wakefulness and cataplexy. Their respective effects on these narcolepsy symptoms were then compared with their in vivo effects on extracellular DA levels in the caudate and NE levels in the frontal cortex during local drug perfusion in narcoleptic dogs. Polygraphic recordings demonstrated that D-amphetamine was about twice as potent as L-amphetamine, and was six times more potent than L-methamphetamine in increasing wakefulness and reducing slow-wave sleep. D-Amphetamine and L-amphetamine were equipotent in reducing rapid eye movement sleep and cataplexy, and L-methamphetamine was about half as potent as L- and D-amphetamines. D-Amphetamine was found to be more potent in increasing DA efflux than L-amphetamine, and L-methamphetamine was found to have little effect on DA efflux; there was no significant difference in the potencies of the three derivatives on NE efflux. The potencies of these amphetamines on wakefulness correlated well with DA, but not NE, efflux in the brain of narcoleptic dogs during local drug perfusion. Our current results further exemplify the importance of the DA system for the pharmacological control of electroencephalogram arousal and suggest that increased DA transmission mediates the wake-promoting effects of amphetamine-like stimulants.

Amphetamine↗
PubMed1999

Thalidomide increases both REM and stage 3-4 sleep in human adults: a preliminary study.

Polysomnography was used to assess the effect of thalidomide on human sleep. This compound significantly increased the time spent in REM and stage 3-4 sleep as compared with placebo. On the other hand, thalidomide significantly decreased the time spent in stage 1, while the time spent in stage 2 was unchanged. The effect of thalidomide on REM and stage 3-4 sleep is unique as compared with other hypnotics. Although the mode of action of this compound is unknown, further studies on thalidomide should help in our understanding of the mechanisms of sleep regulation.

Adult↗
PubMed1998

Sleep-disordered breathing in a patient with congenital myopathy.

A case of adult onset myopathy who showed a peculiar sleep-related respiratory disorder (SRRD) is reported. She recovered from respiratory failure after tracheostomy and/or with the aid of the respirator used only during the night. Sleep study without the use of respirator revealed that her sleep was highly fragmented by frequent arousal responses due to inspiratory effort but not by apnea or hypopnea. To our knowledge this type of SRRD has not been described.

Arousal↗
PubMed1997

Effects of thyrotropin-releasing hormone and its analogs on daytime sleepiness and cataplexy in canine narcolepsy.

The therapeutic potential of thyrotropin-releasing hormone (TRH) and TRH analogs in narcolepsy, a sleep disorder characterized by abnormal rapid eye movement (REM) sleep and daytime sleepiness, was examined using the canine model. The effects of TRH and the biologically stable TRH analogs CG3703, CG3509, and TA0910 on daytime sleep and cataplexy, a symptom of abnormal REM sleep, were assessed using polysomnographic recordings and the food elicited cataplexy test (FECT), respectively. CG3703 (100 and 400 microg/kg, i.v.) and TA0910 (100 and 400 microg/kg, i.v.) significantly increased wakefulness and decreased sleep in narcoleptic canines, whereas TRH (400 and 1600 microg/kg, i.v.) had no significant effect. TRH (25-1600 microg/kg, i.v.) and all three TRH analogs, CG3703 (6. 25-400 microg/kg, i.v., and 0.25-16 mg/kg, p.o.), CG3509 (25-1600 microg/kg, i.v.), and TA0910 (25-1600 microg/kg, i.v.), significantly reduced cataplexy in canine narcolepsy. These compounds did not produce any significant side effects during behavioral assays, nor did they alter free T3 and T4 levels in serum even when used at doses that completely suppressed cataplexy. Although more work is needed to establish the mode of action of TRH analogs on alertness and REM sleep-related symptoms, our results suggest a possible therapeutic application for TRH analogs in human sleep disorders.

Animals↗
PubMed1997

Prognostic factors for renal cell carcinoma: a multivariate analysis of 320 cases.

BACKGROUND: We performed a multivariate analysis of clinical variables in 320 patients with renal cell carcinoma to identify important prognostic factors for long-term survival. METHODS: We retrospectively reviewed the medical records of 320 patients who presented with renal cell carcinoma. Survival curves were calculated by the Kaplan-Meier method and statistical differences were determined by the log-rank test. Significant prognostic factors were evaluated by Cox's multivariate proportional hazard model. RESULTS: The median follow-up period was 29 months. The overall survival rates at 1, 5, and 10 years were 90.0%, 77.6%, and 69.9%, respectively. Seventeen of the 19 prognostic factors evaluated were shown to be significant by the log-rank test: patient age, sex, performance status, body temperature, erythrocyte sedimentation rate (ESR), levels of hemoglobin, alpha 2-globulin, C-reactive protein, fibrinogen, immunosuppressive acidic protein (IAP), size or involvement of tumor (T classification), regional lymph node involvement (N classification), extent of metastasis (M classification), pathologic grade, tumor cell type, mode of tumor infiltration, and the modality of treatment (curative surgery). Among them, the body temperature, ESR, alpha 2-globulin, fibrinogen, IAP, and mode of tumor infiltration were excluded from multivariate analysis because of missing data. Curative surgery was also excluded because it is a treatment modality and different from the other variables which are clinical or pathologic characteristics. From the remaining 10 variables, multivariate analysis showed that age (P = 0.0389), N classification (P = 0.0289), and M classification (P < 0.0001) were important and independent prognostic factors for long survival. CONCLUSION: This analysis showed that age, N classification, and M classification were the most important factors predicting long-term survival of patients with renal cell carcinoma.

Adult↗
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↗
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

Serum prostate-specific antigen values for the prediction of clinical stage and prognosis in patients with prostate cancer: an analysis of 749 cases.

BACKGROUND: The clinical significance of pretreatment serum prostate-specific antigen (PSA) values was studied to determine the ability to predict clinical stage and prognosis using a relatively large number of patients with prostate cancer. METHODS: Serum PSA values at diagnosis were analyzed from 749 patients with newly-diagnosed prostate cancer and registered in the Tokai Urological Cancer Registry. Correlations between the PSA value, the clinical stage and prognosis of the patients were evaluated. RESULTS: Serum PSA values at each stage of diagnosis showed positivity (> or = 3.6 ng/mL) in 23% (stage A1) to 91.2% (stage D2) of patients, and it was possible to obtain statistical differences between the stages, even between A1 and A2. Based on a cumulative study of PSA distribution, stages greater than A2 could be diagnosed using a cut-off of 7.2 ng/mL, with a 99.2% positive predictive value (PPV), and a 16.2% negative predictive value (NPV). At a PSA level of 10.8 ng/mL, stages greater than B2 could be predicted with a PPV of 95.3% but an NPV of 40.3%. Pretreatment PSA values were a significant prognostic indicator in stage D2 patients using 100 to 150 ng/mL as the cut-off values. These differences were primarily found in the poorly differentiated group, which showed a statistical difference using cut-off PSA values from 75 to 150 ng/mL. CONCLUSIONS: Serum PSA levels from a large number of patients can be used to predict the stage and prognosis of prostate cancer patients.

Aged↗