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Biomedical subjects

S Tanabe

Publications and source records attributed to S Tanabe.

At least 343 records · Page 19Linked to original sources
PubMed1989

[Optic nerve hemangioblastoma. Case report].

A solitary hemangioblastoma of the optic nerve was found in a 36-year-old male with a distinct family history of intracranial hemangioblastoma. The patient was admitted with complaints of visual loss and exophthalmos of the right eye. X-rays showed enlargement of the right optic canal. Right carotid angiography revealed a hypervascular tumor in the orbital apex, supplied by the ophthalmic artery. Computed tomography disclosed a pear-shaped, isodense mass with moderate contrast enhancement in the orbital apex. The right optic nerve was enlarged along its entire course and was involved with the apical mass. Surgery via the right frontal extradural approach disclosed a solid, vascular tumor involving the optic nerve at the apex of the orbit. Histological examination showed the tumor to be a characteristic hemangioblastoma. Over 90% of intracranial hemangioblastomas are located in the posterior fossa. Supratentorial hemangioblastomas, especially those arising in the optic nerve, are extremely rare. In addition, optic nerve hemangioblastomas are frequently familial and are associated with infratentorial hemangioblastomas, angiomatosis retinae, and cysts of the abdominal viscera.

Adult↗
PubMed1989

[Studies of enzymuria and proteinuria: Report 2; Relationship between glomerular filtration rate and urinary enzymuria and proteinuria].

Urinary splitting enzymes and proteins including N-acetyl-b-D-glucosanimidase (NAG), beta 2 microglobulin (beta 2MG), and alpha 1 microglobulin: (alpha 1MG), which are established to be useful in the evaluation of renal dysfunction, especially renal tubular impairment, were measured to determine the extent of renal tubular impairment in relation to the degree of glomerular dysfunction in patients with renal deterioration. In healthy volunteers, urinary NAG, alpha 1MG and beta 2MG levels were 3.5 +/- 1.4 (mean +/- SD) U/g creatinine, 2.5 +/- 2.0 mg/l and 88 +/- 75 micrograms/l, respectively. While serum beta 2MG level (SBMG; microgram/ml) was between 2.0 and 2.9, among the patients with renal dysfunction, NAG, alpha 1MG and BMG levels showed 8.6 +/- 5.5, 9.8 +/- 5.8 and 785 +/- 1,264, respectively, and further elevated to 10.1 +/- 5.0, 16.5 +/- 0.7 and 525 +/- 440, respectively with a SBMG level over 3.0. Thus glomerular function was deteriorated, urinary alpha 1MG level elevated to significantly higher with a parallel to renal dysfunction. In patients with more severe renal dysfunction, the corresponding urinary NAG and alpha 1MG levels became significantly higher. However, urinary beta 2MG level was significantly higher in patients with moderate renal dysfunction compared to healthy volunteers only when SBMG level was more than 2.0. Therefore, it was more valuable to measure urinary alpha 1MG with NAG or beta 2MG at SBMG level of less than 1.9 and to determine urinary NAG and alpha 1MG at greater than 2.0. These results indicated that the measurement of the levels of urinary splitting enzymes and proteins is valuable in the evaluation of proximal tubular impairment, even when the degree of glomerular impairment is minimal.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1989

[Angiogenic properties of various tissues utilized for synangiosis in moyamoya disease].

In order to evaluate the adequacy of materials utilized for synangiosis in Moyamoya disease, angiogenic activities of various human tissues were examined. Tissue samples were freshly obtained at operation. A small piece of the sample was placed on the chick chorioallantoic membrane (CAM), and, using an operative microscope, the production of neovascularization was evaluated 96 hours later. The scalp artery (STA and OA) showed the highest activity of angiogenesis, followed by the omentum and galea, while the temporal muscle, dura mater, and fat tissue showed poor activity. Histological examination confirmed the development of vasculature in CAM. The production of neovascularization is known to be related to the tissue content of the angiogenic factor (AF). The AF is known to be present in the vascular endothelial cell, fibroblast, tumor, brain, or omentum, etc. The rationale for the selection of materials for the neovascularization in Moyamoya disease was discussed in relation to its ability to produce new vessels.

Adipose Tissue↗
PubMed1989

[Study on urinary splitting enzymes and proteins. III. Effect of non-ionic contrast medium on renal function].

Renal toxicity of non-ionic contrast medium (iohexol) for drip infused pyelography (DIP) was studied in a randomized trial of nine patients with normal renal function. Urine samples were collected before and immediately after DIP, and analyzed for albumin, an index of glomerular permeability; gamma-glutamyl transpeptidase (gamma-GTP), a brush-border enzyme; N-acetyl-beta-glucosaminidase (NAG), a lysosomal enzyme; alpha 1 microglobulin (alpha 1MG) and beta 2 microglobulin (beta 2MG), an index to tubular proteinuria; and creatinine. The urinary excretion of enzymes and proteins was compared with urinary creatinine. Urinary excretion of gamma-GTP and NAG increased significantly (P less than 0.001, 0.02) after DIP. Urinary alpha 1 MG and beta 2-MG did not change significantly. The change of urinary albumin was mild. Our data suggest that non-ionic, low osmolal radiocontrast medium ioheol shows a lower renal tubular toxicity, and the brush-border enzyme gamma-GTP and lysosomal enzyme NAG are considered as a good index for renal tubular damage.

Acetylglucosaminidase↗
PubMed1989

[Simplified operative technique for thoracoabdominal dissecting aneurysm].

A graft with branches is used to reconstruct the extensively dissected thoracoabdominal aorta. Anastomoses of the proximal end of the main graft distal to the left subclavian artery and the side branch to the distal aneurysmal descending thoracic aorta were first undertaken after the preparation of both ends under the iliac vein-artery partial bypass. A main graft with a Y graft extension was anastomosed distally to iliac arteries. This permits the blood flow within the aneurysm and the main graft to the extremities until splanchnic and spinal cord arteries have individually been transferred to the main graft. Ischemic time of the splanchnic and spinal cord arteries, using this technique, can be minimized within 10 minutes to each in the total replacement of descending thoracic and abdominal aorta.

Adult↗
PubMed1989

[Interposition graft method in the treatment of aortic regurgitation associated with aneurysm of the ascending aorta].

Interposition graft method, total replacement of the ascending aorta with a valved conduit and reimplantation of the coronary artery by an interposed graft with some modifications, had been exclusively used for the treatment of aortic regurgitation associated with an aneurysm of the ascending aorta in consecutive 7 cases. Clinical improvement is apparent and postoperative angiographic study revealed a satisfactory coronary and aortic appearance with no leakage, pseudoaneurysm formation nor compression of the graft. This technique proved to be a reliable and safe method for the treatment of aortic regurgitation associated with an aneurysm of the ascending aorta with no mortality nor modality.

Adult↗
PubMed1988

Determination of oxidizable inorganic anions by high-performance liquid chromatography with fluorescence detection and application to the determination of salivary nitrite and thiocyanate and serum thiocyanate.

A sensitive method for the simultaneous determination of oxidizable inorganic anions (sulphide, thiocyanate, thiosulphate and nitrite) was developed by use of high-performance liquid chromatography and fluorimetric detection based on the formation of fluorescent cerium(III) by a redox reaction with cerium(IV). The detection limits are 0.1 nmol for both thiocyanate and nitrite, 0.3 nmol for thiosulphate and 0.8 nmol for sulphide per 10-microliters injection volume. This system can be utilized for the determination of salivary thiocyanate and nitrite and serum thiocyanate.

Anions↗
PubMed1988

PCB problems in the future: foresight from current knowledge.

The present paper overviews the forthcoming PCB problems from current knowledge of their use, environmental contamination and toxicology. From a global point of view, PCB levels in the environmental media and biota are unlikely to decline in the near future due to the greater quantities of PCBs still in use than the quantity that has already escaped into the open environment. Considering all the information on the occurrence, distribution and behaviour of PCBs in the ecosystems, the marine mammals are probably the most vulnerable and possible target organisms in forthcoming long-term PCB toxicity. The recent isomer-specific analyses suggest that the intrinsic toxicity of PCBs principally resulted from the coplanar PCB congeners which may impose a greater toxic threat than chlorinated dioxins and furans to humans and wildlife. The measures necessary to reduce further discharge of PCBs into the environment should be set in motion immediately, otherwise there may be a subsequent deleterious biological impact.

Journal Article↗
PubMed1988

Central attenuation of baroreflex by angiotensin II in normotensive and spontaneously hypertensive rats.

To determine whether angiotensin II (A II) can modify baroreflex centrally and contribute to the central resetting of baroreflex in spontaneously hypertensive rats (SHRs), the aortic depressor nerve (ADN) was electrically stimulated following intracerebroventricular (ICV) administration of A II and/or A II analog in urethane-anesthetized normotensive Wistar rats (WKYs) and SHRs. Electric stimulation of the ADN elicited frequency-dependent depressor, bradycardic, and sympatho-inhibitory responses. Angiotensin II, administered ICV, dose-dependently attenuated these responses induced by ADN stimulation in normotensive rats. We found, however, these attenuations could be abolished by ICV pretreatment with A II analog. Vasopressin (ICV) did not change any responses to ADN stimulation. The vasopressor and sympatho-inhibitory responses to ADN stimulation were significantly less in SHRs when compared with those in WKYs: In SHRs, A II analog completely cancelled the A II-attenuated responses to ADN stimulation. These findings suggest that A II can centrally attenuate baroreflex, which might be independent from vasopressin, and in the brain A II can contribute to the central resetting of baroreflex in SHRs.

Angiotensin II↗
PubMed1988

Central attenuation of baroreflex precedes the development of hypertension in DOCA-salt-treated rats.

To determine whether baroreflex is changed centrally before the development of hypertension in DOCA-salt treated rats, aortic depressor nerve was stimulated electrically 5 days after DOCA-salt treatment in urethane-anesthetized rats: compared with those of sham-operated control rats, blood pressure was not elevated in either awake or anesthetized rats. Aortic depressor nerve (ADN) stimulation elicited frequency-dependent vasodepressor, bradycardiac, and sympatho-inhibitory responses in both DOCA-salt-treated and control rats. However, the responses to ADN stimulation were significantly smaller in DOCA-salt-treated rats. These findings suggest that baroreflex is attenuated centrally before the development of hypertension and this attenuation may contribute to the pathogenesis of DOCA-salt hypertension.

Animals↗
PubMed1988

Increased extracellular concentration of norepinephrine in the hypothalamus by sinoaortic denervation.

To determine whether baroreflex can affect the norepinephrine system in the hypothalamus, the extracellular concentration of norepinephrine were measured by the brain dialysis technique in sinoaortic denervated rats (SAD). Twenty-four hours after sinoaortic denervation, systolic blood pressure and heart rate were significantly elevated, and norepinephrine concentration in perfusate of the posterior hypothalamus was significantly higher in SAD rats than in sham-operated rats. These results suggest that baroreflex could modify the activity of noradrenergic neuron projecting to the posterior hypothalamus.

Animals↗
PubMed1988

Enhancement of adenosine-induced relaxant responses of the guinea-pig isolated taenia coli and aortae by a novel nootropic agent BY-1949: comparison with dipyridamole.

In muscle strips of guinea-pig taenia coli and aortae, the effects of 3-methoxy-11-methyldibenz[b,f][1,4]oxazepine-8-carboxylate (BY-1949) on the relaxant response to adenosine have been compared with those of dipyridamole. BY-1949 (3 x 10(-5)-10(-4) M) as well as dipyridamole (3 x 10(-7)-10(-5) M) resulted in a significant potentiation of relaxant responses to a cumulative administration of adenosine (10(-6)-10(-3) M), but the drugs did not affect the response to noradrenaline and acetylcholine. The results indicate that BY-1949 exerts a selective potentiating effect on reactivity to exogenous adenosine.

Adenosine↗
PubMed1988

[Effect of metoprolol in patients with renal hypertension].

Eighteen patients with renal hypertension were treated with metoprolol (Seloken) for more than 3 months. Compared with the pretreatment value, the mean blood pressure decreased by 6.0, 11.2, 9.2 and 12.2 mmHg, after 2 weeks and 3, 6 and 12 months of treatment with metoprolol, respectively. All the differences observed were statistically significant (p less than 0.01). The blood pressure lowering effect of metoprolol was observed in 12 of the 17 patients (70.6%) examined. Decrease in plasma renin activity was seen in most of the responders. Although the number of patients was limited, the plasma level of metoprolol was also measured. The results indicated no sign of accumulation of metoprolol in the body. Moderate deterioration in renal function was observed in 1 patient but the treatment with metoprolol could be continued. Metoprolol administration had to be discontinued in 1 patient, who developed asthma. There were no other serious side effects.

Adult↗