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Biomedical subjects

Kazuyoshi Watanabe

Publications and source records attributed to Kazuyoshi Watanabe.

At least 55 records · Page 3Linked to original sources

Mutations of neuronal voltage-gated Na+ channel alpha 1 subunit gene SCN1A in core severe myoclonic epilepsy in infancy (SMEI) and in borderline SMEI (SMEB).

PURPOSE: Severe myoclonic epilepsy in infancy (SMEI) is a distinct epilepsy syndrome. Patients with borderline SMEI (SMEB) are a subgroup with clinical features similar to those of core SMEI but are not necessarily consistent with the accepted diagnostic criteria for core SMEI. The aim of this study was to delineate the genetic correlation between core SMEI and SMEB and to estimate the frequency of mutations in both phenotypes. METHODS: We examined 96 healthy volunteers and 58 unrelated individuals whose clinical features were consistent with either core SMEI (n = 31) or SMEB (n = 27). We screened for genetic abnormalities within exons and their flanking introns of the genes encoding major subunits of the Na+ channels (SCN1A, SCN2A, SCN1B, and SCN2B) by using a direct sequencing method. RESULTS: In both core SMEI and SMEB, various mutations of SCN1A including nonsense and missense mutations were identified, whereas no mutations of SCN2A, SCN1B, and SCN2B were found within the regions examined. All mutations were heterozygous and not found in 192 control chromosomes. Mutations were identified in 26 (44.8%) of the 58 individuals and were more frequent (p < 0.05) in core SMEI (19 of 31) than in SMEB (seven of 27), as assessed by the continuity-adjusted chi2 test. Mutations resulting in a molecular truncation were found only in core SMEI. Among the mutations, two missense mutations were found in both core SMEI and SMEB. CONCLUSIONS: Our findings confirm that SMEB is part of the SMEI spectrum and may expand the recognition of SMEI and suggest other responsible or modifying genes.

Amino Acid Sequence↗

A follow-up survey on seizures induced by animated cartoon TV program "Pocket Monster".

PURPOSE: To identify the short-term outcome of patients who had seizures while watching an animated cartoon TV program, "Pocket Monster," on December 16, 1997. METHODS: One and three years after the incident, questionnaires were sent to physicians of each patient about seizure recurrence, EEGs, and medication. RESULTS: Among 103 patients in whom epileptic seizures occurred during the TV program and information on the outcomes was available, 25 (24%) patients had a history of unprovoked seizures before the incident (Epilepsy Group), and 78 (76%) did not (Non-Epilepsy Group). Twenty-three (22%) patients were reported to have seizures after the incident, and 15 of them had visually induced seizures. Patients of the Epilepsy Group had more seizure recurrence than did those of the Non-Epilepsy Group (56% vs. 9%; p < 0.0001), either for unprovoked (44% vs. 4%; p < 0.0001) or visually induced seizures (28% vs. 9%; p < 0.05). Of nine patients of the Non-Epilepsy Group who had seizures after the incident, only three developed recurrent unprovoked seizures. In the Non-Epilepsy Group, no difference was found in seizure recurrence between patients in whom valproate (VPA) was prescribed immediately after the incident and in those without medication (one of five (20%) vs. seven of 73 (10%); p > 0.05). EEG was performed at least once in 98 patients after the incident. Photoparoxysmal response (PPR) was present in 45 (46%) patients, and spontaneous epileptiform discharges, in 49 (50%). PPR did not have any correlation with recurrence of seizures, neither spontaneous nor visually induced seizures, whereas spontaneous epileptiform discharges showed a good correlation with seizure recurrence (34% vs. 8%; p < 0.01), including visually induced seizures (24% vs. 2%; p < 0.01). CONCLUSIONS: Short-term outcomes showed that 70 (68%) of 103 patients who had a seizure during the incident had no seizures before and during < or = 3 years of follow-up.

Adolescent↗

[Campylobacter fetus subsp. fetus sepsis: a case report and review of the literatures in Japan].

We report a 32-year-old female with eating disorder whose body weight was only 20 kg. She was admitted to the hospital with severe low nutrition, low proteinemia, liver dysfunction, hypokalemia and hypoglycemia. On the third hospital day, she had a high fever and Campylobacter fetus subsp. fetus (C. fetus) was isolated from the blood. After treatment with meropenem (1 g/day) intravenous drip injection, her condition improved. C. fetus sepsis is not common disease in Japan. A review of 37 cases of this disease in Japan revealed that the age range of adult patients was 20 to 60 years old. The male-to-female ratio was 4.6 to 1.0. Seventy-eight percent of the patients had underlying diseases which were composed of 11 patients with liver disease, 6 patients with blood dyscrasia and some with diabetes mellitus, heart disease, other malignant tumor and collagen disease. There was no case with eating disorder. All apparent sources of infection in Japan originate from eating raw food. Gastrointestinal symptoms were observed in only 16% of the patients. Recent recommendations for the treatment of C. fetus sepsis are to use gentamicin, imipenem and meropenem. Some strains of C. fetus have resistance to erythromycin, ciprofloxacin. The mortality of this infection is 14% in Japan.

Adult↗

A sensitive method for 4-hydroxybutyric acid in urine using gas chromatography-mass spectrometry.

4-Hydroxybutyric acid (4HB) was analyzed by gas chromatography-mass spectrometry. Under acidified conditions, 4HB is difficult to detect due to lactonization. Using a urine sample containing 0.01 mg creatinine, we performed trimethylsilyl derivatization without extraction, only adding dimethylsuccinic acid as an internal standard and 10 microl of 0.1 N NaOH methanol solution with adequate evaporation. Urine 4HB levels in a patient with 4-hydroxybutyric aciduria was determined to be 1258 mmol/mol Cr (control, 0.28-2.81 mmol/mol Cr) in this method. Direct derivatization of samples without extraction showed good reproducibility and linearity. Only a small sample of urine was required. Alkalinization by NaOH prevented not only lactonization of 4HB, but also loss of the compounds during evaporation.

Child↗

Abnormal sharp transients on electroencephalograms in preterm infants with periventricular leukomalacia.

OBJECTIVE: To determine the clinical significance of abnormal sharp transients other than positive rolandic sharp waves (PRS), electroencephalograms were used for the diagnosis of periventricular leukomalacia (PVL). STUDY DESIGN: We evaluated 126 electroencephalograms from 93 preterm infants; 31 infants had PVL, and 62 were control infants. Frontal sharp waves (FS) were defined as sharp transients of positive polarity with an amplitude >100 microV. Occipital sharp waves (OS) were defined as those of negative polarity with an amplitude >150 microV. FS, OS, or PRS were considered to be present when there were >0.1 per minute. RESULTS: The number of FS per minute was significantly higher in the PVL group than in the control group during days 0 to 4 and 5 to 7. The number of OS per minute was also significantly higher in the PVL group than in the control group during days 0 to 4, 5 to 7, and 8 to 14. The sensitivity of FS or OS was relatively high but that of PRS was low. The presence of two or more types of abnormal sharp transients was correlated with a poor outcome. CONCLUSIONS: FS or OS may be useful for predicting which infant will have PVL.

Cerebral Palsy↗

Third ventricular chordoid glioma: case report and review of the literature.

BACKGROUND: Chordoid glioma of the third ventricle is a rare type of brain tumor that was recently characterized as a novel tumor entity. We present a case and review of the literature. CASE REPORT: A 49-year-old woman presented with progressive headache, memory impairment and urinary incontinence. MRI showed a large well-circumscribed tumor in the third ventricle. The tumor was partially removed via a trans-lamina terminalis approach. The histologic findings indicated chordoid glioma. Residual tumor was treated by stereotactic radiosurgery and showed no regrowth at 2-year follow-up. CONCLUSIONS: The ideal therapy is total removal of the tumor. However, according to the literature, total removal of the tumor carries a high risk because of its location, and conventional radiation therapy has little effect on the residual tumor. On the other hand, stereotactic radiosurgery appears more promising, and to date, no regrowth has been reported after gamma-knife therapy.

Brain Neoplasms↗

Hypoxic ischemic encephalopathy associated with neonatal seizures without other neurological abnormalities.

We reported three term or near-term infants with parasagittal infarcts. Their Apgar scores were low and the amniotic fluid was meconium-stained. Resuscitation was necessary immediately after birth, but they were not stuporous and no neurological abnormalities were recognized on admission. They showed metabolic acidosis and transient hypoglycemia, and two showed hematoemesis. Seizures were observed between 2 and 15 h of age in all of them. Electroencephalography demonstrated moderate or severe depression, and CT demonstrated bilateral abnormal low densities in the border zones of the middle and posterior cerebral arteries. Two of them had mental retardation and epilepsy, although the other exhibited normal development. Our infants suggest that neonatal seizures can also occur in infants with hypoxic ischemic encephalopathy without apparent neurological abnormalities.

Anticonvulsants↗

A case of subacute sclerosing panencephalitis preceded by epileptic seizures: evolutional EEG changes.

We reported a patient with subacute sclerosing panencephalitis (SSPE) in whom EEG had been serially performed before the onset. She was referred to our hospital due to epileptic seizures at 2 years of age. Focal spikes were seen on EEG at the time of her first seizure (2 years 4 months). At the time of the second unprovoked seizure (9 years 8 months), EEG showed poorly organized background activity associated with focal spikes and a few diffuse spike-and-waves. Then, diffuse paroxysms became predominant, followed by periodic synchronous discharges. In our case, EEG abnormalities were recognized before mental deterioration. Unexpected EEG changes in a patient with epilepsy could be a clue as to the diagnosis of SSPE.

Brain↗

Amplitude spectral analysis of maturational changes of delta waves in preterm infants.

The aim of this study is to clarify the usefulness of amplitude spectral analysis for an evaluation of maturational changes of delta activities in preterm infants. We chose each ten healthy infants without complications who were 29-30, 31-32, and 33-34 weeks of post-conceptional age (PCA) at electroencephalogram (EEG) recordings. Fast Fourier transform algorithm was applied for amplitude spectral analysis. The analyzed data were divided into four frequency bands; D1 0.53-1, D2 1-2, D3 2-3, and D4 3-4Hz. The average amplitude of six segments with high voltage slow waves was calculated in each frequency band. A significant reduction of the amplitude along with PCA was present in all leads in D1 band. On the other hand, a significant negative correlation with PCA was observed only in the occipital leads in D2, D3 or D4 bands. In conclusion, maturational EEG changes assessed by amplitude spectral analysis were prominent in the occipital areas, and in the frequency less than 1Hz.

Algorithms↗

Absence seizures in patients with localization-related epilepsy.

We studied the clinical features of 12 patients with localization-related epilepsy (LRE) associated with absence seizures (AS). AS did not appear in any patients before partial seizures (PS) were first observed. The interval between the onset of PS and AS ranged from 1 month to 7.2 years (mean 2.11 years). The duration of AS (mean 5 months) was short compared with that of PS (mean 3.8 years). Carbamazepine (CBZ) was used in seven patients at the onset of AS. It was discontinued in five but continued in the other two. AS was initially treated with valproate in ten patients. Three of them needed additional antiepileptic drugs: clonazepam in two patients and ethosuximide in one. All patients became free from AS after treatment for AS was started, whereas PS was relatively intractable. Generalized spike-and-waves were often observed before the onset of AS. The interval between the first appearance of generalized spike-and-waves and the onset of AS ranged from 1 to 53 months (mean 20 months). AS in patients with LRE will be relatively benign and transient, and will respond well to antiepileptic drugs.

Adolescent↗

Sharp waves in preterm infants with periventricular leukomalacia.

We studied the incidence of positive and negative sharp waves in two pairs of twin infants with periventricular leukomalacia and compared it with that of normal cotwins by using remontage and refiltering functions of digital electroencephalography. Three electroencephalograms were serially performed in each infant. After the usual visual inspection with bipolar montage and low-cut filter of 0.5 Hz, the electroencephalogram montage was changed into monopolar derivation, and the low-cut filter into 5 Hz. The number of positive or negative sharp waves per minute, with an amplitude of more than 50 microV, was independently calculated. The number of negative sharp waves was large in the occipital and Pz areas in both infants with periventricular leukomalacia. The number of positive ones was large in the Cz area in both infants with periventricular leukomalacia. Disorganized patterns were observed in all electroencephalograms in the infants with periventricular leukomalacia on visual inspection. In conclusion, digital electroencephalography analysis using remontage and refiltering demonstrated an increased number of sharp transients in preterm infants with periventricular leukomalacia. The application of a higher low-cut filter will be useful for the assessment of sharp transients in neonatal electroencephalography.

Diseases in Twins↗

Bronchodilator effects of intravenous olprinone, a phosphodiesterase 3 inhibitor, with and without aminophylline in asthmatic patients.

AIMS: There is no evidence demonstrating the clinical usefulness of phosphodiesterase (PDE) inhibitors in the treatment of asthma, although PDE3 and 4 inhibitors have received much attention for the treatment of bronchial asthma. We compared the bronchodilator effects of intravenously administered olprinone, a selective PDE3 inhibitor, and aminophylline, a nonselective PDE inhibitor, both alone and concomitantly. METHODS: In 12 patients with mild stable asthma, we compared the acute bronchodilator effects of the following two drugs, alone and together using a double-blind crossover design: intravenous administration of olprinone, 30 micro g min-1; aminophylline, 2.25 mg min-1; and olprinone plus aminophylline over a total period of 150 min. RESULTS: Mean maximal increase (95% confidence interval) in the FEV1 was 7.8% (2.4, 13.2), 17.1% (10.0, 24.2), 16.6% (11.2, 22.0), and 1.0% (-1.1, 3.1) during infusion of aminophylline, olprinone, aminophylline and olprinone, and saline, respectively. The magnitude of bronchodilatation produced by olprinone was greater than that by aminophylline. The combination of aminophylline and olprinone did not produce any greater bronchodilatation than olprinone alone. Olprinone alone or in combination with aminophylline lowered diastolic blood pressure, and increased heart rate. CONCLUSIONS: These results suggest that the intravenous administration of PDE3 inhibitors exhibits a bronchodilatory effect. There are no additive or synergistic effects of administration of olprinone and aminophylline at the same time.

3',5'-Cyclic-AMP Phosphodiesterases↗

The predictive value of electroencephalogram during early infancy for later development of West syndrome in infants with cystic periventricular leukomalacia.

PURPOSE: The aim of this study was to elucidate a predictive value of electroencephalogram (EEG) during early infancy for later development of West syndrome (WS) in premature infants with cystic periventricular leukomalacia (PVL). METHODS: The subjects of this study were 19 infants with cystic PVL born between 1992 and 1996. EEGs were recorded at 3 months of corrected age (CA) in all of them. We divided these 19 infants into the following two groups; group A (n = 9), no paroxysmal discharge was recognized; and group B (n = 10), paroxysmal discharges were recognized. RESULTS: In none of the infants in group A did WS develop. Subsequent EEGs were normal in all infants in group A. WS developed in seven of 10 infants in group B. The occurrence of WS is significantly higher in group B than in group A. The mean age at the onset of WS was 6 months of CA. Paroxysmal discharges in infants in group B were observed as irregular spikes-and-waves and polyspikes-and-waves, mainly in bilateral parietooccipital areas. In seven of eight patients with severe MRI findings in group B, WS developed. CONCLUSIONS: Paroxysmal discharges during early infancy were correlated with later development of WS in infants with cystic PVL. The possibility of developing WS had increased in the children with the combination with EEG and MRI findings.

Age of Onset↗

Nutritional state and growth and functional maturation of the brain in extremely low birth weight infants.

OBJECTIVE: It is well-known that an undernutritional status influences central nervous system development in the fetal and early neonatal period. On the other hand, the maturational delay of the central nervous system is reflected as dysmature pattern (DMP) in the neonatal background electroencephalograph (EEG). Therefore, we hypothesized that the postnatal nutritional status influenced electrophysiologic maturation in extremely low birth weight infants (ELBWIs). METHODS: ELBWIs between 24 and 27 weeks of gestational age who were admitted to Ogaki Municipal Hospital NICU from April 1997 to December 2000 were considered eligible. From the condition of enteral feeding, infants were divided into 2 groups: 1). normal nutritional group (group N), where enteral feeding had been established (100 mL/kg/d) by 3 weeks after birth; 2). undernutritional group (group U), where enteral feeding had not been established by 3 weeks after birth or was discontinued because of clinical problems. Weekly average body weight and head circumference gains were evaluated as nutritional status. EEG records were performed every 2 to 4 weeks until postnatal 15 weeks of age. DMP was defined as the appearance of immature EEG patterns for postconceptional age. RESULTS: Twenty-one infants had serial EEG recordings; 11 infants belonged to group N and 10 infants to group U. Gestational age, birth weight, and head circumference at birth were not different between the 2 groups. The body weight of group N was significantly heavier than that of group U after 5 postnatal weeks. Similarly, the head circumference of group N was larger than that of group U after 6 weeks of postnatal age. Nine infants demonstrated DMPs. One infant belonged to group N and 8 to group U. DMPs were significantly more frequently found in group U than group N (80% vs 9%). In 6 of the 9 cases, the DMPs lasted until 38 to 40 weeks of postconceptional age. Five of the 6 infants with persistent DMPs suffered from severe undernutritional conditions. The other, who belonged to group N, was treated with corticosteroid for chronic lung disease. In 3 cases, DMPs were observed transiently and their undernutritional status was not so severe. CONCLUSIONS: Our study indicated that a postnatal undernutritional condition was associated with DMPs in ELBWIs. Undernutritional status may affect electrophysiologic maturation.

Brain↗

Human cortical responses to coherent and incoherent motion as measured by magnetoencephalography.

To investigate the detail response properties for the incoherent motion of the human visual system, we measured the magnetoencephalographic neural responses to both coherent and incoherent motions at various speeds (from 0.65 to 20.6 degrees /s). The peak latency of the first component of the response from the extrastriate area was inversely related to the speed of motion (from 228 to 155 ms in mean) and there was no significant difference in the latency change between the two types of motion. There were significant differences in the peak amplitude change with the motion speed and a difference in the distribution of the magnetic fields of the responses was seen in six of the seven subjects. The results show that the speed of the incoherently moving dots is represented in the human visual system in the same manner as that of coherently moving dots. The differences in the magnetic fields between the two responses indicate that the same speed-related response changes can occur with different neural populations responsible for both motions.

Adult↗

A pilot study on umbilical venous level of natriuretic peptides in preterm infants and their relation to periventricular leukomalacia and antenatal complications.

The aim of this study was to determine the relation between umbilical venous levels of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in preterm infants, and the development of periventricular leukomalacia (PVL) and antenatal complications. Umbilical venous blood samples were obtained from 19 preterm infants with gestational age between 27 and 32 weeks. Cystic PVL was seen in four of them on ultrasonography. Several maternal variables were also investigated. There were no significant differences in ANP or BNP level between infants with and without PVL. Both ANP and BNP levels were significantly higher in infants with antenatal magnesium administration than in those without. Umbilical venous levels of natriuretic peptides were not useful to predict neurological outcome in preterm infants.

Atrial Natriuretic Factor↗

Cardio-facio-cutaneous syndrome and moyamoya syndrome.

We reported a patient with cardio-facio-cutaneous (CFC) syndrome associated with moyamoya syndrome. The patient was referred at 6 years 5 months with left hemiplegia and right-sided eye deviation. He had an apparently short stature, macrocephaly, left ptosis and atopic skin, and was odd looking. He exhibited an incomplete right bundle branch block on electrocardiogram and an atrial septal defect on ultrasound cardiography. He was diagnosed as having CFC syndrome. Head magnetic resonance imaging showed a flow void in the bilateral basal ganglia, but did not show any ischemic changes. Magnetic resonance angiography showed bilateral stenosis with an internal carotid artery at the Willis artery ring level and bilateral moyamoya. Contrast angiography demonstrated occlusion of both middle cerebral arteries. Cerebrovascular anomalies have not previously been reported in CFC syndrome. This is the first case of CFC syndrome associated with moyamoya syndrome.

Abnormalities, Multiple↗