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T Kishikawa

Publications and source records attributed to T Kishikawa.

At least 91 records · Page 5Linked to original sources

Effect of oxytocin on spontaneous electrical and mechanical activities in pregnant human myometrium.

Spontaneous intracellular electrical activity and contraction of pregnant human myometrium were recorded by the single sucrose-gap method, and the effects of oxytocin on the muscle were studied. In pregnant human myometrium at term, both plateau and spike types of action potentials were observed. All contractions were well synchronized with each action potential. Oxytocin, 10(-2) U/ml, potentiated spontaneous contractions by enhancing the plateau part of action potentials; spike-type configuration became plateau. When extracellular ionized calcium was removed, spontaneous activities disappeared, while 10(-2) U/ml of oxytocin could evoke action potentials and contractions but these were smaller than those of the controls. Spontaneous activities also disappeared when ionized calcium was increased to 5 mmol/L, but oxytocin evoked plateau potentials and contractions remarkably. Diltiazem (ionized calcium antagonist), 10(-6) gm/ml, suppressed the spontaneous activity, but oxytocin evoked action potentials and contractions in high frequency, the duration of the action potential being short and the contraction being small. In the presence of 10(-4) gm/ml of diltiazem, 10(-2) U/ml of oxytocin could not evoke any action potentials but did evoke small and long contractures, while in a high ionized potassium contracture experiment, oxytocin potentiated the tonic phase. These results suggest that oxytocin can increase spontaneous contractions by enhancing plateau potentials and that this effect requires sufficient extracellular ionized calcium. In this potentiation, the effects on frequency and amplitude of contractions might vary. It is also suggested that oxytocin may evoke a contracture in the absence of an action potential by releasing calcium from intracellular storage sites.

Action Potentials↗

Cerebrovascular occlusive disease with and without the moyamoya vascular network in children.

Clinical features of cerebrovascular occlusive disease with the moyamoya network (group 1: twenty-nine children) and those without this network (group 2: nine children) are reported herein. Group 1 was characterized by female preponderance, recurrent and transient ischemic attacks, progression of mental deterioration, rebuild-up after hyperventilation on EEG and wide-spread lesions on CT scan. Group 2 had one or two attacks which led to a rather long-lasting hemiplegia but not to mental deterioration, rare rebuild-up findings on EEG and unilateral focal lesion on CT scan. Precipitating factors for ischemic attacks included deep breathing, changes in body temperature or sleep-waking transition were present in both groups. Etiology in some children was considered to be congenital.

Arterial Occlusive Diseases↗

The value of CT in diagnosis and prognosis of different inborn neurodegenerative disorders in childhood.

Inborn errors of metabolism in 40 children have been investigated by computed tomography to obtain data on the degree of cerebral involvement in neurodegenerative and storage disorders: 20 children had various mucopolysaccharidoses, 8 sphingolipidoses , 3 mucolipidoses, 2 oligosaccharidoses , 3 ceroidlipofuscinoses and 4 had various leucodystrophies . Diagnosis in all patients except Alexander's disease was established by biochemical or histological means. The main findings on CT were cerebral atrophy with enlargement of the ventricles and the subarachnoid spaces and hypodensity of the white matter. The degree of cerebral atrophy seemed to develop according to the age of the patients, as could be seen from the patients with mucopolysaccharidosis III, metachromatic leucodystrophy and GM1-gangliosidosis. Hypodensity of the white matter was found in mucopolysaccharidosis I-H, II-B, VI, in mucolipidosis II and in patients with leucodystrophies . On the other hand, there was great variability in these CT findings even in siblings, as seen in four patients with mucopolysaccharidosis VI. Among the series there were several patients who did not show any abnormalities in CT, so that a negative CT did not exclude these disorders, even the leucodystrophies . CT features such as cerebral atrophy or hypodensity were helpful in the evaluation of these disorders, though a diagnosis could not be made by CT alone.

Adolescent↗

Hepatic mensenchymal hamartoma of an infant.

An 8-month-old boy was found to have a solitary hepatic mesenchymal hamartoma. Histologically, the lesion appeared as a large island of loose mesenchymal tissue with few cystic bile ducts and liver cells. Electronmicroscopy showed microvilli on the surface of tumor cells and desmosomes between the cells. Immunohistochemical studies showed that alpha-fetoprotein was localized in the proliferating liver cells and bile ductal epithelium of this neoplasm. This case is the 17th case of hepatic mesenchymal hamartoma reported in Japan.

Hamartoma↗

Moyamoya disease associated with renovascular hypertension.

Findings at the autopsy of a 7-year-old Japanese girl with moyamoya disease associated with renovascular hypertension are reported. There was disruption of a saccular aneurysm located at the junction of the left posterior cerebral and the posterior communicating arteries. Intimal thickening of carotid, coronary, and renal arteries, similar to findings in cases of intimal hyperplasia of fibromuscular dysplasia, was observed. These findings indicate that moyamoya disease may actually be an intracranial manifestation in a systemic arterial disorder.

Arterial Occlusive Diseases↗

Primary brainstem hemorrhage in a child: usefulness of auditory brainstem response (ABR).

We treated a child with primary brainstem hemorrhage who recovered fairly well. The Auditory Brainstem Response (ABR) correlated well with the clinical course and CAT findings. Primary brainstem hemorrhage leads to neurological abnormalities which may be fatal (Silverstein 1972). As there is apparently no documentation on the correlation between CAT scan and ABR findings in such patients, we report our experience with primary brainstem hemorrhage in a child who recovered.

Adolescent↗

Central nervous system complications in childhood leukemia. Correlation between clinical and computed tomographic findings.

We used cranial computed tomography (CT) to evaluate 51 leukemic patients with or without central nervous system (CNS) symptoms. Among 17 symptomatic patients, nine had gross abnormalities on CT scans; leukemic infiltrations, infections (CNS aspergillosis), hemorrhages, and therapy-related complications were all evident. One with a leukemic infiltration showed a periventricular low density on the CT scans. The differential diagnosis of CT findings and the correlation between clinical and CT findings is described. The significance of a low-density area observed in an asymptomatic patient on long-term intrathecal methotrexate therapy for CNS leukemia is also discussed.

Brain↗

[A case of prolactinoma with galactorrhea in man].

A 28-year-old man was admitted to the Kyushu University Hospital with an episode of severe headache. When driving a car, he suddenly developed severe headache and this was followed by nausea and vomiting. he had been quite well except for slightly decreased libido before this episode. On admission, he showed galactorrhea. The pubic and axillary hairs appeared normal and the development of the external genital organs seemed normal. However, the movement of the sperma was decreased. Ophthalmologic examination was negative. Endocrinological studies revealed hyperprolactinemia of 697 ng/ml, and the serum prolactin level was suppressed by bromocriptine and L-DOPA loading test. The serum testosterone level was 282 ng/dl. Growth hormone and gonadotropin levels were normal. Plain films of the skull and tomograms of the sella showed double floor and slight ballooning. CT scan showed an isodensity mass in and above the sella, and this mass was slightly enhanced with contrast media. The suprasellar extension was better demonstrated by metrizamide cisternography and CT. The diagnosis of prolactinoma was made, and a radical removal of the tumor was done through the transsphenoidal route. During surgery, dark reddish fluid was aspirated in an amount of 1.8 ml. Histologically the tumor was chromophobe adenoma, and immunohistochemical stain revealed prolactin granules in the majority of the tumor cells. Postoperative serum prolactin level decreased to 150 ng/ml and finally returned to normal by administration of 2.5 mg of bromocriptine. The serum testosterone level was slightly elevated. The movement of the sperma showed no improvement. There were no postoperative complications such as hypopituitarism and CSF rhinorrhea. The usefulness of combination therapy of operation and medication with bromocriptine was suggested.

Adenoma↗