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Biomedical subjects

M Kagawa

Publications and source records attributed to M Kagawa.

At least 109 records · Page 6Linked to original sources
PubMed1988

Positive influence of dietary deoxycholic acid on development of pre-neoplastic lesions initiated by N-methyl-N-nitrosourea in rat liver.

The effect of deoxycholic acid (DCA) treatment subsequent to initiation of F344 male rats with N-methyl-N-nitrosourea (MNU), a wide spectrum carcinogen inducing tumors in many organs, was investigated. Rats were initially given four doses of MNU (50 mg/kg) i.p. within a 2-week period combined with a two-thirds partial hepatectomy performed at day 7 and then placed on basal diet containing DCA at concentrations of 0.313, 0.125, 0.050 and 0.020% for 21 weeks prior to final sacrifice. All organs studied were carefully examined histologically and histochemically for development of neoplastic and pre-neoplastic lesions. DCA enhanced the induction of glutathione S-transferase positive (GST-P+) liver cell foci in a dose-related manner. Furthermore groups of rats given DCA without prior MNU administration also developed dose-dependent numbers of pre-neoplastic liver lesions. In addition, increased numbers of small intestine tumors were apparent in DCA-treated animals although the difference was not significant. Induction of tumors in the thyroids, Zymbal glands, skin and peripheral nerves was not affected. The results indicate that DCA is a strong promoter of hepatocarcinogenesis with possible complete carcinogenicity in the liver and promotion potential for tumor development in the small intestine.

Animals↗
PubMed1988

Mapping of local cerebral blood flow with stable xenon-enhanced CT and the curve-fitting method of analysis.

A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.

Adult↗
PubMed1988

[Ossified choroid plexus papilloma--case report].

While the calcification has been documented radiologically in 4 - 25 percent of the cases with choroid plexus papilloma, the ossification of choroid plexus papilloma has been reported only in 3 cases on literature. In this paper, we present a case of large ossified choroid plexus papilloma in the right lateral ventricle. A 35-year-old man was admitted with left hemiparesis and headache. Skull X-rays showed an abnormal calcified mass (25 mm x 23 mm x 14 mm) in the right temporal region. CT scan revealed an abnormal high density area protruding into the right lateral ventricle, and a low density area at the right corona radiata. Operation was carried out with a right temporal craniotomy. The mass was yellowish-elastic hard and protruded into the right inferior horn of the lateral ventricle. The histological examination of surgical specimen showed an ossified choroid plexus papilloma with some bone marrow formation and numerous calcification. Calcification of choroid plexus papilloma is found frequently, but ossification is a very rare neuropathological abnormality. Bone and/or cartilage formation in neuroepithelial neoplasms is an unusual event histopathologically. Several mechanisms have been proposed, such as (1) metaplasia of connective tissue, (2) transformation of neuroepithelial cells to mesenchymal tissue, (3) teratomatous nature, (4) heteroplasia, (5) mixed mesenchymal-neuroepithelial nature, and (6) ossification as an end stage of mucoid degeneration. In our case, it was considered that the bone formation resulted from metaplasia of connective tissue of choroid plexus papilloma.

Adult↗
PubMed1988

[Cerebral ischemia (1)--Reversibility of ischemic lesion and CT findings].

Two hundred and twenty-one patients with cerebral cerebral ischemic attack in the middle cerebral artery territory were investigated. Those patients manifested several clinical types, TIA: 31, stroke with full recovery: 50, minor completed stroke: 54 and major completed stroke: 86 cases. CT classification was made 3 weeks after the ischemic attack based on the characteristic arterial topography. We discussed in this paper what kind of ischemic lesion had greater possibility of recovery from ischemic lesion had greater possibility of recovery from ischemia focusing on the retrospective study of clinical symptoms, CT classification and angiographic findings. We also referred to the other factors influencing the reversibility of an ischemia such as lacunae and PVH (periventricular hypodensity). The extent of and LDA on CT scan closely correlated with clinical symptoms, CT classification and angiographic findings. We also referred to the other factors influencing the reversibility of an ischemia such as lacunae and PVH (periventricular hypodensity). The extent of an LDA on CT scan closely correlated with clinical types (Table 2). The reversibility of type I was excellent, however aged patients over 70 with PVH and ventricular dilatation developed permanent neurological impairment associated with dementia. The reversibility of a small infarction in the basal ganglia (type II) depended mainly on the involvement of the internal capsule. Infarction involving a cortex (type IV and type V) invariably resulted in permanent neurological deficits except for the rare cases with involvement of silent areas. CT classification of type III, so called demarcation zone infarction, developed various clinical types, and showed transient functional disturbance of the cortex without an infarction i the cortico-subcortical region.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Measurement of local cerebral blood flow by computerized tomography with inhalation of stable xenon and curve-fitting method].

Non-invasive methods are described for estimating local cerebral blood flows (LCBF) and local partition coefficients (L lambda) during inhalation of 30% stable xenon gas (Xe) in oxygen during CT scanning. After the denitrogenation with pure oxygen breathing, 30% Xe is inhaled for four minutes to minimize subanesthetic effects with a rubber face-mask and the delivery system of Xe. Local time-delta Hounsfield units curve during the Xe wash-in and wash-out phase is utilized in order to calculate L lambda and LCBF using a least squares curve fitting analysis. Calculated L lambda and LCBF with the new method manifested reasonable distribution between the grey and white matters, and reproducibility was excellent in our study. Several case studies of patients with cerebral infarction are presented to demonstrate the characterization of L lambda and LCBF patterns in various tissues and theoretical grounds underlying the new method of curve fitting analysis are discussed.

Adolescent↗
PubMed1987

Metabolic interaction between toluene and ethanol in rabbits.

The metabolic interaction of toluene and ethanol was studied in male rabbits having received ethanol (26.0 mmol/kg PO), toluene (5.4 mmol/kg PO) or both. Compared with ethanol alone, toluene given 2 h after ethanol caused a significantly higher and more prolonged concentration of blood alcohol. A similar trend of blood alcohol was observed at the later stage with toluene given prior to ethanol. On the other hand, with simultaneous doses of the two substances, the blood toluene concentration was higher for the first 15-30 min than the ethanol control and the urinary excretion of hippuric acid, a main metabolite of toluene, was markedly decreased for the first 2 h. The blood ethanol in this group, on the contrary, was reduced until 1 h after administration. These results indicate that toluene and ethanol act reciprocally as competitive inhibitors in their metabolism after single administrations.

Animals↗
PubMed1987

Induction of forestomach lesions in rats by oral administrations of naturally occurring antioxidants for 4 weeks.

The effects of naturally occurring antioxidants on rat forestomach epithelium were compared with those of synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), of which the former is a known forestomach carcinogen. Groups of five F344 male rats were given diet containing BHA, BHT, gallic acid, syringic acid, sesamol, caffeic acid, chlorogenic acid, ferulic acid, eugenol or esculin for 4 weeks at a level of 0.7% for BHT or 2% for other compounds. Histological examination of the forestomach showed that BHA induced hyperplasia mainly in the prefundic region near the esophageal orifice, caffeic acid induced pronounced hyperplasia throughout the forestomach epithelium, and sesamol induced large ulcers and hyperplasia in the central region. Thus, these naturally occurring antioxidants showed different toxicities and abilities to induce hyperplasia in the rat forestomach.

Animals↗
PubMed1986

Hemorrhagic stroke in infancy, childhood, and adolescence.

The authors report on factors influencing the outcome after hemorrhagic strokes in infants, children, and adolescents over a period of 14 years. Their series comprised primary hemorrhage in 24 cases (46.2%), including 5 cases of vitamin K deficiency; arteriovenous malformation in 20 cases (38.5%); intracranial aneurysm and moya-moya disease in 3 cases (5.7%) each; and spinal angioma in 2 cases (3.9%). Ten of 52 patients with juvenile hemorrhagic strokes died despite surgical treatment. These fatal cases involved an intraparenchymal hematoma with ventricular casts, and unilateral hydrocephalus suggesting acute, uncontrollable intracranial hypertension. The "child's biologic plasticity" plays an important role in the favorable prognosis in infants, children, and adolescents with hemorrhagic strokes. On the contrary, cases with intraventricular hemorrhage due to any pathologic condition have an unfavorable prognosis.

Adolescent↗
PubMed1986

Forme fruste of von Recklinghausen's disease: unilateral association of an orbital neurofibroma, a trigeminal neurinoma, and an acoustic neurinoma. Case Report.

A patient who presented with a tumor of the left ambient cistern, a left cerebellopontine angle tumor, and a left orbital tumor causing left hearing loss and left exophthalmos without café au lait spots or cutaneous neurofibromas is described. There was no family history of von Recklinghausen's disease. A cerebellopontine angle tumor removed by a suboccipital craniectomy was an acoustic neurinoma. An ambient cistern tumor was approached through a subtemporal route. A tumor arising from the trigeminal nerve was also a neurinoma. An orbital neurofibroma was excised by a frontal craniotomy with removal of the orbital roof. This rare unilateral association of neurinomas and a neurofibroma on the left side was thought to be a forme fruste of von Recklinghausen's disease, and it could be considered a presentation of a mosaic of von Recklinghausen's disease.

Adult↗
PubMed1986

[Autoimmune antibody in moyamoya disease].

The association of autoimmune antibody and HLA antibody has been documented concerning the pathogenesis of moyamoya disease. In this paper, we study the autoimmune antibody in moyamoya disease and discuss its relationship with the pathogenesis. Autoimmune antibody was evaluated in 13 cases of moyamoya disease. The age distribution of the patients ranged from 13 to 55, with an average of 37 years. Eight were females, 5 males. Autoantibody was studied with native DNA (double strand DNA) and ANA (antinuclear antibody). Antibody was noted in 3 cases (23%) in native DNA study, and 2 cases (15%) in ANA study. Significantly high incidence was recognized compared with normal control (4%). In relation to the clinical features, such as initial symptoms, time of onset, neurological findings, no significant correlation was recognized. This study suggests that immunological factors might play a partial role in the pathogenesis of moyamoya disease.

Adolescent↗
PubMed1986

[A case of pituitary adenoma combined with Rathke's cleft cyst].

A case of pituitary adenoma associated with Rathke's cleft cyst is reported. A 35-year-old woman suffering from visual disturbance, polydipsia-polyuria and amenorrhea galactorrhea was admitted. Since 3 years before admission, she had been administered thyradin under the diagnosis of primary hypothyroidism. Visual acuity was 0.1 on the right and 0.06 on the left, and visual field examination showed bitemporal hemianopsia. Endocrinological study disclosed primary hypothyroidism and moderate hypopituitarism. CT scan showed a low density mass with ring-like enhancement extending in the enlarged sellar cavity and in the suprasellar region. MRI showed a cystic mass in the sellar cavity extending to the suprasellar region, and a solid mass in the left posterior part of the sellar cavity, and the later was thought to be pituitary adenoma. On August 27, 1984, right frontal craniotomy was performed. The right optic nerve was compressed upward, and the right carotid artery laterally with a grayish bulging mass. About 3 ml of grayish colloidal fluid was aspirated and the capsule of the cyst was excised. Postoperative course was uneventful. The visual acuity and visual field defects were improved. Endocrine examination revealed panhypopituitarism. Histologically, the cyst wall was composed of ciliated columnar cells and partially stratified squamous cells. The solid part showed typical pituitary adenoma. There are 5 reports in the literature on the combination of a pituitary adenoma and a Rathke's cleft cyst. In our case, it is thought that the long-standing hypothyroidism induced pituitary adenoma. Therefore, our case with combination of a pituitary adenoma and a Rathke's cleft cyst should be regarded as an occasional coexistence rather than the entity of the transitional cell tumor.

Adenoma↗
PubMed1986

[Grading and operative indication for hypertensive cerebellar hemorrhage].

Fifty six patients with hypertensive cerebellar hemorrhage diagnosed by CT scan were hospitalized from November 1976 up to June 1984. The 35 male and 21 female patients ranged in age from 24 to 84 years, and 39 of them were operated on. The important factors related to prognosis of cerebellar hemorrhage were level of consciousness, size of hematoma on CT scan, and massive ventricular hemorrhage resulting in obstruction of the ventricular system. We classified the patient with cerebellar hemorrhage into 5 grades, according to the severity of these factors. Grade I indicates cerebellar signs without disturbance of consciousness and size of hematoma less than 25 mm measured by CT scan. Grade II indicates disturbance of consciousness (stupor), or progressive neurological deficits, and size of hematoma less than 50 mm without acute hydrocephalus. Grade III reveals disturbance of consciousness (stupor-semicoma), and size of hematoma less than 50 mm with acute hydrocephalus. Grade IV reveals severe disturbance of consciousness (semicoma), and size of hematoma less than 50 mm with massive ventricular hemorrhage. Grade V exhibits deep coma, and more than 50 mm diameter of hematoma. The prognosis of all of 9 patients in Grade I was good, Eleven out of 13 patients (85%) in Grade II and all of 9 patients in Grade III were alive. Fourteen out of 19 patients (74%) in Grade IV and all of 6 patients in Grade V expired in spite of operation. The patients of Grade I should be treated by conservative therapy. The patients of Grade II, Grade III, and Grade IV should be managed surgically. Surgical treatment for Grade V is not advisable.

Adult↗