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T Shima

Publications and source records attributed to T Shima.

At least 199 records · Page 11Linked to original sources
PubMed1988

[Pathophysiological studies in moyamoya disease by rCBF and cortical artery pressure measurements in comparison to those in ICA or MCA occlusion].

The authors measured preoperative rCBF and intraoperative cortical artery pressure (CAP) during STA-MCA anastomosis to investigate cerebral hemodynamics in moyamoya disease. Six of 13 patients including 3 children showed ischemic attack and the remaining presented hemorrhagic attack. rCBF was measured by single photon ECT with Xe-133 inhalation technique. CAP's and rCBF's in moyamoya disease were compared to those in the 22 internal carotid artery (ICA) and 8 middle cerebral artery (MCA) occlusion. Systemic arterial blood pressure (SABP) was obtained at the radial artery. Mean rCBF in the MCA territory in moyamoya disease, ICA occlusion, and MCA occlusion were 39, 37, and 33 ml/100 g/min respectively. Mean SABP and CAP in moyamoya disease were 103 and 28 mmHg, respectively. In ICA occlusion, mean SABP and CAP were 98 and 45 mmHg, respectively. In MCA occlusion, mean SABP and CAP were 89 and 36 mmHg, respectively. To clarify the hemodynamics, vascular resistance was obtained from the following equations: The proximal vascular resistance (Rp), which was produced from the cervical ICA to cortical artery, was obtained by (mean SABP - mean CAP)/(rCBF). And distal vascular resistance (Rd) which was produced from the cortical artery to jugular vein, was obtained by (mean CAP)/(rCBF). Mean Rp in moyamoya disease ICA occlusion and MCA occlusion were 2.01, 1.21 and 1.70, respectively. Rd in moyamoya disease, ICA occlusion and MCA occlusion were 0.79, 1.37 and 1.22, respectively. There were significant differences in Rp and Rd between moyamoya disease and ICA or MCA occlusion. In ischemic group in moyamoya disease, rCBF, SABP, CAP, Rp and Rd were 41 ml/100 g/min, 111 mmHg, 28 mmHg, 1.92 and 0.70, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Arterial Occlusive Diseases↗
PubMed1987

Measurement of CLL

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Journal Article↗
PubMed1987

A possible relationship between cord blood transferrin and birth length in infants.

Cord blood levels of transferrin (Tf) and insulin-like growth factor I (IGF-1) were measured in 33 normal and 12 preterm infants. Tf was measured by the single radial immunodiffusion technique, while IGF-1 was measured by specific RIA. Tf levels in normal term infants (195 +/- 27 mg/dl) were significantly below normal adult levels (261 +/- 12 mg/dl). Tf levels in preterm infants (159 +/- 30 mg/dl) were lower than those in normal term infants. Tf levels showed a positive correlation with birth length, weight, gestational age and albumin levels in all infants. There was no correlation between Tf and IGF-1 levels in term and preterm infants.

Birth Weight↗
PubMed1987

[A case of basilar artery fenestration with recurrent attacks of vertebrobasilar insufficiency].

Fenestration of basilar artery is an uncommon vascular anomaly that is usually an incidental product on autopsy or angiography. None of the cases in the literature had clinical symptoms associated with this anomaly except for subarachnoid hemorrhage when accompanied with saccular aneurysm. We report a rare case of the basilar artery fenestration associated with clinical symptoms without any aneurysm. A 71-years-old male, who had been treated for labile hypertension and had had recurrent attacks of vertigo, nausea, sometimes diplopia or unsteady gait, for 5 years, was referred to our hospital on Sept. 13, 1985. One day prior to admission, he suddenly felt diplopia and vertigo and unsteady gait. His family noticed he was dysarthric. On admission, he was alert and normotensive. He complained of dysesthesia on the right half of the perioral region and his right fingers. A neurological examination showed a mild weakness and hyperactive deep tendon reflexes on his right leg. His motor coordination was almost normal, but he was unsteady when he stood on one foot with his eyes closed. Laboratory examinations were normal except for an elevated serum uric acid level. A chest x-ray film showed a sclerotic change of aorta and mild cardiomegaly. Left ventricular hypertrophy was observed on his ECG. His CT scans showed multiple lacunae and mild brain atrophy. On cerebral angiography, his basilar artery (BA) had a fenestration almost in its total length that divided the BA, like a duplication, into two components with a smaller diameter than normal.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1986

Transferrin receptor on rat Kupffer cells in primary culture.

Kupffer cells may play a role in the turnover of iron in acute viral hepatitis. The transferrin receptor of rat Kupffer cells in primary culture was therefore investigated in this study. Daily specific bindings on 125I-diferric transferrin (Tf) to rat Kupffer cells in primary culture from day 3 to day 6 of culture were 1.64 +/- 0.08%, 4.16 +/- 0.05%, 4.34 +/- 0.07% and 2.63 +/- 0.07%, respectively. The specificity of the Tf binding sites was examined by competition studies showing that galactose (30 mmol x l-1) and ovalbumin (90 mumol x l-1) did not compete for the binding sites, but human lactoferrin (50 mumol x l-1) competed for the binding sites by about 30%. The affinity and capacity of Tf receptor on rat Kupffer cells in 5-day culture were analyzed according to the method of Scatchard. A single class of 125I-diferric Tf binding sites with an affinity constant of 1.65 x 10(7) l x l-1) and a capacity of 6.86 x 10(6) sites/cell was found. After zymosan (500 micrograms/ml) preincubation for 30 min, the binding capacity increased about 1.7-fold, and this increase depended upon the increase of the affinity of Tf receptor. These data suggest that Kupffer cells in the activated state accelerate the removal of elevated serum iron.

Animals↗
PubMed1985

[A TRH analog (DN-1417). Effects on the levels of monoamines and the metabolites in the various brain regions in rats].

The effects of a TRH (thyrotropin-releasing hormone) analog, DN-1417 (gamma-butyrolactone-gamma-carbonyl-L-histidyl-L-prolinamide citrate), on the levels of norepinephrine (NE), dopamine (DA), serotonin (5-HT) and the metabolites in the various brain regions of rats were determined by means of high performance liquid chromatography with electrochemical detection. DN-1417 (20 mg/kg, i.p.) produced marked decreases in the levels of NE, DA and 5-HT, especially in the nucleus accumbens, striatum and hypothalamus. The maximum effect was observed at 15 min after the administration. DA metabolites, 3,4-dihydroxyphenylacetic acid and homovanillic acid, increased significantly in the nucleus accumbens, striatum and hypothalamus, whereas 3-methoxy-4-hydroxyphenylglycol and 5-hydroxyindoleacetic acid remained unchanged. 3-Methoxytyramine increased significantly in the nucleus accumbens and striatum. Two week chronic administration of DN-1417 (20 mg/kg, i.p.) increased the levels of DA and NE in the nucleus accumbens and DA in the striatum. These results suggest that DN-1417 stimulates the turnover of the cerebral monoamines, especially the release of DA from the nucleus accumbens and striatum in the mesolimbic and nigro-striatal DAergic systems.

Animals↗
PubMed1985

[Clinical trial of MCNU for malignant brain tumors].

A total of 71 cases with primary brain tumors (44 cases) and metastatic brain tumors (30 cases) were entered into our clinical studies with MCNU and radiation therapy or MCNU alone. With regard to tumor reduction on CT scan, the response rates obtained for MCNU and radiation were 21.7% for malignant gliomas and 50.0% for metastatic brain tumors. With regard to improvement of neurological signs, the response rates obtained for MCNU and radiation were 62.9% for malignant gliomas and 71.4% for metastatic brain tumors. The response rates for MCNU were 5.8% for malignant gliomas and 46.1% for metastatic brain tumors. In the improvement of performance status, the response rates for MCNU and radiation were 51.8% for malignant gliomas and 64.2% for metastatic brain tumors. The response rates for MCNU were 46.1% for malignant gliomas and 30.7% for metastatic brain tumors. A minimal degree of hematological toxicity occurred but this gradually disappeared. These results suggested that MCNU has relatively effective antitumor activity against metastatic brain tumors and an enhanced effect with radiation against malignant gliomas.

Antineoplastic Agents↗
PubMed1984

Effect of middle cerebral artery compression on pial artery pressure, blood flow, and electrophysiological function of cerebral cortex of cat.

In 20 cats, the left middle cerebral artery was gradually compressed with a microdriven vascular occluder implanted by a transorbital approach. Pial artery pressure, cortical blood flow, segmental vascular resistance, electrocorticogram, and cortical steady potentials were measured in the territory of the left middle cerebral artery and correlated with the degree of vascular stenosis. Pial artery pressure began to decrease when the lumen of the middle cerebral artery was reduced to 200 micrometers. Cortical blood flow and EEG power declined when pial artery pressure fell below 35-40 mm Hg; cortical steady potential started to shift toward negativity at a pressure below 25-30 mm Hg; and both hemodynamic and electrophysiological changes were maximal at a pressure below 10 mm Hg. When the vascular occlusion was released within 5 min after the onset of ischemia, a pial artery pressure of only 18 mm Hg was necessary to restore normal blood flow. After 1-h occlusion, normalization of flow occurred at a pressure of 30 mm Hg. Since this pressure is still substantially below normal pial artery pressure, no-reflow does not seem to be of significance in this experimental situation.

Animals↗
PubMed1984

[A case of internal carotid dolichoectasia].

A 50-year-old woman noticed right motor and sensory paralysis in the morning of December 15, 1978, which improved gradually to be able to walk during 20 days. She had recurrence of incomplete paralysis of right extremities with speech disturbance and admitted to our department on April 7. Neurological examination revealed right hemiparesis. Plain skull rentogenorgram showed a calcification extending posteriorly from the left anterior clinoid process. CT scan showed a mass lesion located at the left frontal lobe to the ambient cistern. The mass lesion showed high density, but its midportion was isodensity. The left carotid angiogram demonstrated abnormally curved, tortuous and dilated internal carotid artery at the intracavernous portion (C3) to bifurcation (C1). The cerebral circulation time was greatly delayed, which regained about 6 seconds for the visualization of the distal portion of the middle cerebral artery. On the basis of the above, we considered that the first right hemiparesis was due to emboli produced in the dolichoectasia and the following progressive stroke was attributable to the low perfusion demonstrated by a great delay of circulation time. The operation was performed to trap the dolichoectasia after STA-MCA anastomosis. However, trapping procedure was very difficult because of hardness of the distal portion of the involved artery. Therefore, surgery was concluded with STA-MCA anastomosis and only proximal internal carotid clipping. The postoperative angiography demonstrated well functional anastomosis and obliteration of dolichoectasia. She discharged on improvement of her condition on the 23rd day after operation. CT scan performed 6 months after operations showed the mass lesion to have become definitely reduced in size. The application of bypass surgery to the internal carotid dolichoectasia was reported with review of the literatures.

Brain Ischemia↗
PubMed1983

Experimental microsurgical embolectomy after middle cerebral artery embolization in the dog.

The effects of microsurgical embolectomy were investigated clinicopathophysiologically in 60 dogs after occlusion of the middle cerebral artery (MCA) trunk with a silicone cylinder embolus. One group of animals served as a control (non-embolectomized group), and in the other two groups the embolus was removed 3 or 6 hours after occlusion (3-hour or 6-hour embolectomy group). In the non-embolectomized animals, major neurological deficits with deep cerebral infarction were observed. Regional cerebral blood flow (CBF) in the basal ganglia decreased most prominently. Sensory evoked potentials also declined to about 50% of the control level 3 hours after embolization. In the 3-hour embolectomy group, mild neurological deficits with minimal infarctions were found. One hour after embolectomy, CBF was restored to the original level in all regions, and the sensory evoked potentials surpassed the control level. In the 6-hour embolectomy group, most animals exhibited major neurological deficits and severe brain swelling with hemorrhagic infarction. This study suggests that early microsurgical embolectomy of the MCA trunk restores blood flow in the perforating arteries and prevents deep cerebral infarction.

Animals↗
PubMed1983

Comparison of middle cerebral artery trunk occlusion by silicone cylinder embolization and by trapping.

The authors produced occlusion of the middle cerebral artery (MCA) trunk in dogs by two methods: silicone cylinder embolization and trapping. Comparative analyses of the clinicopathological features in these models, extending from the acute to chronic stage, were performed. Within 24 hours after embolization, the brain exhibited swelling without macroscopic infarction. Microangiograms revealed impaired filling in the deep areas of the brain with midline shift. At 4 to 7 days after embolization, the animals showed major neurological deficits, evident deep cerebral infarction, and poorly perfused areas in the deep cerebrum with prominent midline shift. At 3 to 4 weeks after embolization, the neurological deficits improved and the affected regions showed cavities or localized lesions. Microangiograms demonstrated hypervascular areas with abnormal vessels in the affected cerebrum. On the other hand, trapping of the MCA trunk produced mild neurological deficits, although there was no evidence of macroscopic lesions or impairment of filling. This study shows that silicone cylinder embolization in the MCA trunk produces a reliable and reproducible deep cerebral infarction in dogs.

Animals↗
PubMed1983

Regional cerebral blood flow, sensory evoked potentials, and intracranial pressure in dogs with MCA occlusion by embolization or trapping.

Regional cerebral blood flow (rCBF), sensory evoked potentials (SEP), and intracranial pressure (ICP) were investigated in dogs with focal cerebral ischemia produced by a silicone cylinder embolus in the middle cerebral artery (MCA) trunk as compared to that produced by trapping the same vessel. These variables were measured at intervals of 1 hour for a period of 6 hours after MCA occlusion. In the embolized animals, rCBF decreased most extensively at the basal ganglia, from a control level of 53.9 +/- 3.9 (mean +/- SE) to 21.5 +/- 2.7 ml/100 gm/min at the 6th hour. Sensory evoked potentials decreased progressively from the resting level of 100% to 53.0% +/- 7.2% at the 3rd hour. Intracranial pressure, measured by epidural pressure on the occluded side, increased rapidly during the first 3 hours, from 10.6 +/- 0.3 to about 30 cm H2O. In the animals with trapping, the decreases in rCBF and declines of SEP were significantly less than those in the embolized animals, and no evident brain swelling was observed. This study demonstrates that MCA trunk occlusion by silicone cylinder embolization produces a more marked decrease in deep CBF, with diminution of SEP and increase in ICP, than that produced by trapping.

Animals↗