Biomedical subjects

T Minami

Publications and source records attributed to T Minami.

465 records · Page 26Linked to original sources

PubMedDate not supplied

A case of neonatal spinal cord injury: magnetic resonance imaging and somatosensory evoked potentials.

This is the first case report on the diagnosis of spinal cord injury due to hemorrhage during the neonatal period using magnetic resonance imaging (MRI). Somatosensory evoked potentials are also helpful in the functional demonstration of this lesion. When discrepant signs, alert consciousness and intact cranial nerves are observed in newborn babies with flaccid extremities and respiratory disturbance, the immediate carrying out of MRI is mandatory in order to differentiate spinal cord injury from hypoxic-ischemic encephalopathy, cerebral hemorrhage, and neuromuscular disease.

Electric Stimulation↗

PubMedDate not supplied

Drug interactions of zonisamide with phenytoin and sodium valproate: serum concentrations and protein binding.

The influence of co-medication with zonisamide (ZNS) on the serum concentration and protein binding of phenytoin (PHT) and sodium valproate (VPA) was studied in 21 pediatric patients. No significant correlation between the daily ZNS dose, and total serum concentrations, free concentrations or free fractions (FF) of PHT or VPA was observed. The patient study showed that changes in the FF of PHT and VPA were correlated more closely with the serum protein and bilirubin levels than changes in the ZNS dosage. An in vitro study revealed that the addition of ZNS caused decreases in the FF of PHT and VPA. However, these decreases were within the range of measurement error and were negligible. In conclusion, no significant effect of ZNS on the serum concentration or protein binding of PHT or VPA was demonstrated.

Adolescent↗

PubMedDate not supplied

Maturational changes of VEPs in normal premature neonates: a longitudinal study.

In order to clarify the maturational changes of visual evoked potentials (VEPs) in normal premature neonates, longitudinal recordings were obtained for 11 normal premature neonates at low risk, at intervals of mainly 1 week and occasionally 2 weeks. Positive waves around 200 ms, P200, negative waves around 300 ms, N300, and positive waves around 400 ms, P400, were recognized. Since P200 and P400 exhibited more variability in latency and appearance than N300, maturational changes in the N300 component were analyzed. The latency of monophasic N300 showed transient prolongation from 32 to 35 weeks gestational age (GA) and re-shortening after 35 weeks GA, or slow regression from 32 to 35 weeks GA and a steady decrease after 35 weeks GA. The bifid N300 showed a shift of dominancy from the first negative peaks to the second peaks, and after 35 weeks GA latency shortening of the second peaks. These findings suggested that the decrease in N300 latency in the premature period may comprise two stages, a slow regression rate or reverse stage from 32 to 35 weeks GA, and a fast regression rate stage from 35 to 38 weeks GA, and that N300 may consist of two components, early and late ones, with the same polarity. This study indicates that careful attention should be paid to evaluation of VEPs in premature neonates.

Age Factors↗

PubMedDate not supplied

Cortical somatosensory evoked potentials to posterior tibial nerve stimulation in newborn infants.

Successful cortical recordings of somatosensory-evoked potentials (SEPs) to posterior tibial nerve (PTN) stimulation were obtained in 21 (87.5%) for P1 and 22 (91.7%) for N1 of 24 infants who were followed up for at least 3 years and had a normal outcome. There were linear decreases with increasing post menstrual age in both P1 and N1 peak latency. Of the four cases with diplegia later, three showed definite abnormalities, no responses and delayed latency in PTN SEPs respectively, however, the other case showed normal responses. Of the three cases with mental retardation, two showed relatively long latency and borderline responses respectively, and the other case showed normal responses. As the pathway of PTN SEPs traverses the periventricular area of the brain likely to be affected by ischemic lesions in premature infants, abnormalities in the responses might indicate a later motor disorder.

Electric Stimulation↗

PubMedDate not supplied

Evoked potentials in neonates and infants with aseptic meningitis.

We investigated 4 infants with aseptic meningitis, 4-38 days of age, by repeated electroencephalography (EEG), flash-visual evoked potentials (F-VEPs), and brainstem auditory evoked potentials. The patients all had mild, acute phases and favorable outcomes at 1-2 years of age. EEGs and F-VEPs obtained within 1 month after onset all were defined as abnormal. In 3 patients, EEG findings were normal 1-2 months after onset, while F-VEP findings were normal at 9-10 months. Brainstem auditory evoked potential findings were normal, except for 1 with otitis media. Evoked potentials suggested that subclinical brain damage, especially due to cortical lesions, persisted during the first year of life in these patients clinically diagnosed with "meningitis."

Evoked Potentials, Auditory↗

PubMedDate not supplied

Transient neurologic abnormalities and BAEPs in high-risk infants.

We examined brainstem auditory evoked potentials in 2 neurodevelopmentally different groups of high-risk premature infants during the first year of life. Our 77 patients were considered at birth to be at risk for neurologic disabilities, but were found to have normal development in the second year of life. The patients were divided into 2 groups on the basis of their neurologic findings during the first year of life; 24 of the 77 patients demonstrated transient neurologic abnormalities (group I) and the remaining 53 demonstrated normal neurologic findings through the first year of life (group II). Normative data of brainstem auditory evoked potentials were obtained from 60 low-risk and neurologically normal infants. Group I patients had prolonged III-V and I-V intervals at 2 months of age or younger and poorly detectable waves VI and VII at 5 months of age or younger, compared with control subjects. Wave VI was poorly detected in group II patients only at 35-39 weeks of conceptional age. Brainstem auditory evoked potentials suggested that the patients with transient neurologic abnormalities had transient dysfunction or maturational delay in the brainstem and upper auditory pathway early in the first year of life.

Evoked Potentials, Auditory, Brain Stem↗

PubMedDate not supplied

Plasma and testicular testosterone in experimental diabetic rats.

Testicular and plasma testosterone levels were found to be decreased markedly in streptozotocin diabetic rats compared with those of controls. Treatment with 6 units NPH insulin daily for one week almost normalized plasma testosterone levels parallel to the increase in body and liver weights in diabetic rats, while testosterone levels in testicles were not significantly changed. Plasma prolactin and LH levels were unchanged among control, diabetic and diabetic insulin-treated rats. Thus, testosterone reduction in the testis might play a role in diabetic impotence.

Animals↗

PubMedDate not supplied

Influence of additional therapy with zonisamide (Excegran) on protein binding and metabolism of carbamazepine.

The influence of comedication with zonisamide (ZNS) on protein binding and carbamazepine (CBZ) metabolism was studied in 16 pediatric epileptic patients. Correlations were evaluated between ZNS daily dose and individual change of level per dose ratio (L/D ratio), free fraction, and carbamazepine-10,11-epoxide/CBZ level ratio (CBZE/CBZ). Statistical significant negative correlation was observed between L/D ratio and ZNS daily dose. Despite alteration in the L/D ratio, the free fraction of CBZ was unaltered in combination with ZNS. To assess the effect of addition of ZNS on CBZ metabolism, the CBZE/CBZ level ratio was compared; this ratio showed a tendency to increase with increase in ZNS dose. Consequently, ZNS is considered to have a significant effect on CBZ metabolism but not on protein binding.

Adolescent↗

PubMedDate not supplied

Inhibitory effects of oolong tea extract on caries-inducing properties of mutans streptococci.

The inhibitory effects of oolong tea extract (OTE) on the caries-inducing properties of mutans streptococci were examined in vitro. OTE reduced the rate of acid production by mutans streptococci accompanied with the retardation of growth rate of mutans streptococci, while the action by chromatographically isolated oolong tea polyphenol (OTF6) was weak. On the other hand, both oolong tea products decreased cell surface hydrophobicity of almost all the oral streptococci examined in the present study, and also induced cellular aggregation of Streptococcus mutans, Streptococcus oralis, Streptococcus sanguis or Streptococcus gordonii. In these reactions, OTF6 showed a more pronounced activity than OTE. Furthermore, the oolong tea products inhibited the adherence of mutans streptococci to saliva-coated hydroxyapatite. These results suggest that OTF6 may inhibit bacterial adherence to the tooth surfaces by reducing the hydrophobicity of mutans streptococci, and OTE may inhibit caries-inducing activity of mutans streptococci by reducing the rate of acid production.

Bacterial Adhesion↗

PubMedDate not supplied

Positive scans in angiographically proved cases of recanalized cerebral infarction.

In 20 patients with acute major cerebral arterial occlusion, follow-up angiograms were obtained to inspect the occluded artery. These angiograms were compared with brain scans in the fourth week after the stroke. The angiograms revealed that frequent recanalization of the occluded arteries occurred within a week after the onset. On the other hand, brain scans showed the increased uptake of radioisotopes even in the patients with angiographically demonstrated arterial recanalization. The present study clarified that positive scans could be obtained in the patients with and without recanalization, and emphasized the diagnostic value of brain scans in the subacute or chronic stage of cerebral infarction, especially in patients with no arterial occlusion appearing on the angiograms.

Acute Disease↗

PubMedDate not supplied

Angiographical extravasation of contrast medium in hemorrhagic infarction. Case report.

Leakage of the contrast medium was noted on angiograms of a patient whose autopsied brain disclosed typical pathological findings of hemorrhagic infarction. The case was a 63-year old woman with mitral valve failure, who suddenly had loss of consciousness and right-sided hemiplegia. The left carotid angiography performed six hours after onset demonstrated middle cerebral arterial axis occlusion, and the second angiography performed three days after onset displayed recanalization of the initially occluded artery as well as extravasation of the contrast medium. Fourteen days after onset the patient died and an autopsy was performed. The brain demonstrated perivascular punctate hemorrhages in the area supplied by the middle cerebral artery, and neither hematoma nor microaneurysm was disclosed pathologically. A short discussion is given on the possible relationship between recanalization and hemorrhagic infarction. The clinical assessment of hemorrhagic infarction has not been established successfully.

Cerebral Angiography↗

PubMedDate not supplied

Sanguineous cerebrospinal fluid in recanalized cerebral infarction.

To clarify the causal relationship between spontaneous recanalization of the occluded cerebral artery and development of hemorrhagic infarction, 15 patients with internal carotid or middle cerebral arterial axis occlusion were submitted to consecutive lumbar punctures and follow-up cerebral angiography. Consequently, six of seven recanalized patients had sanguineous cerebrospinal fluid (CSF) on the second or third day after ictus, while only one of eight non-recanalized patients had bloody CSF. It was strongly suggested that recanalization might have an initimate relationship with the development of hemorrhagic infarction.

Adult↗

PubMedDate not supplied

Diagnostic reliability of the percutaneous ultrasonic Doppler technique for vertebral arterial occlusive diseases.

There is little data on the diagnostic reliability of the ultrasonic Doppler technique for vertebral arterial occlusive lesions. Percutaneous vertebral Doppler examination and the vertebral angiograms were compared to determine the diagnostic reliability of this technique in 64 vertebral arteries of 53 patients with cerebrovascular disease. The percutaneous vertebral Doppler findings were quantitatively analyzed using a sound spectrograph and were classified into three types: no flow signal type, poor flow type and normal flow type. In nine patients with the no flow type the angiograms revealed vertebral occlusion or a missing vertebral artery in six, giving a diagnostic reliability of 67%. In 17 patients with poor flow type the angiograms revealed vertebral occlusion or a missing vertebral artery in five, terminal narrowing of the artery in nine, and hypoplasia in two giving a diagnostic reliability of 94%. For all vertebral arteries examined with this technique, including normal ones, the diagnostic reliability was 92% (59/64). Percutaneous vertebral Doppler examination has clinical usefulness as a screening test for occlusive vertebral arterial diseases.

Adult↗

PubMedDate not supplied

Relationship between ophthalmic artery blood flow and recanalization of occluded carotid artery. Ultrasonic Doppler study.

Ophthalmic artery blood flow in 5 patients with internal carotid artery occlusion of sudden onset was monitored by an ultrasonic Doppler flowmeter to investigate the possible relationship to spontaneous recanalization of the occluded artery. The occluded internal carotid arteries of 2 patients were confirmed angiographically to recanalize and the reversed flow of their ophthalmic arteries changed to physiological flow after the recanalization. The ophthalmic artery blood flow remained reversed in 2 patients whose occluded internal carotid arteries did not recanalize on the follow up angiograms. In the other patient, whose ophthalmic artery blood flow was not detected by the ultrasonic Doppler flowmeter in the acute stage, physiological flow through the ophthalmic artery was detected later. The occluded internal carotid artery did not recanalize and this physiological ophthalmic artery blood flow was filled through the circle of Willis.

Acute Disease↗

PubMedDate not supplied

Rearrangement, amplification and overexpression of c-Ha Ras gene in premalignant lesion of Turcot's syndrome.

Ras gene family (c-Ha, Ki, N ras) and c-myc proto-oncogenes were analyzed in seven colonic and three gastric adenomatous polyps obtained from a patient with Turcot's syndrome. The rearrangement and amplification as well as overexpression of c-Ha ras gene in one colonic adenomatous polyp were determined. The amplified c-Ha ras gene in this polyp revealed larger fragments of BamHI, PstI and SacI than those in the normal colonic mucosa from the same patient. But, such abnormalities were not observed in other polyps. No abnormalities of c-Ki ras, c-N ras or c-myc gene were observed in any polyps. These results suggest that the alternations of c-Ha ras gene in this patient may not be responsible for the adenomatous change, but may be related to the transition from adenoma to carcinoma of the colon.

Adenoma↗