Search PubMed⌕ Search

Biomedical subjects

S Ueda

Publications and source records attributed to S Ueda.

At least 685 records · Page 38Linked to original sources
PubMed1990

Effects of nifedipine on renal cortical and medullary blood flow in two-kidney, one-clip renovascular hypertension in rabbits.

The effects of nifedipine, a calcium antagonist, on blood pressure and renal regional blood flow were investigated in two-kidney, one-clip renovascular hypertensive rabbits. At 1 week after left renal artery constriction, in the constricted group, systemic blood pressure (BP) significantly rose with the elevation of plasma renin activity (PRA). In both kidneys, renal vascular resistance (RVR on the constricted group was significantly increased as compared to that in the control group. In the clipped kidney, total renal blood flow (RBF) and renal cortical blood flow (RCBF) of the constricted group were significantly decreased, while renal medullary blood flow (RMBF) remained at the control value. In the nonclipped kidney, RBF and RCBF of the constricted group did not significantly change, and RMBF was significantly increased as compared to that of the control group. After administration of nifedipine for 1 week (1.0 mg/kg/day), BP in the constricted group was decreased to the control level and PRA in both groups was increased. The percent change of BP in the constricted group was significantly decreased and the percent change of PRA in the constricted group was significantly increased as compared to those in the control group. Nifedipine increased RBF, RCBF and RMBF and decreased RVR of both kidneys in each group. In the nonclipped kidney, the percent change of RBF, RCBF and RMBF of the constricted group was significantly increased and the percent change of RVR was significantly decreased as compared to those of the control group. In the clipped kidney, only the percent change of RBF of the constricted group was significantly lower than that in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Chloride efflux in cyclic AMP-induced configurational change of bovine pulmonary artery endothelial cells.

Elevation of cellular cyclic AMP by agents such as isoproterenol plus 3-isobutyl-1-methylxanthine produced rapid and reversible dendritic formation of bovine pulmonary artery endothelial cells in the monolayer. The effect did not occur with exposure of the cells to a variety of other vasoactive agents, calcium ionophore, phorbol ester, or cyclic GMP. The cyclic AMP-induced configurational change was completely inhibited by 2.5 mM N-phenylanthranilic acid or 145 mM sodium gluconate (Cl- channel inhibitors) and was partially inhibited by 2.5 mM 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid (SITS), but it was not affected by deprivation of Ca2+ or Na+ ion, 1 mM bumetanide (Cl- cotransport inhibitor), 1 mM amiloride (Na+/H+ exchange inhibitor), 0.1 mM verapamil (Ca2+ channel inhibitor), or 5 mM BaCl2 (K+ channel inhibitor), by change in cellular pH, or by pertussis toxin. Trifluoperazine (calmodulin inhibitor, 50 microM), 1 mM EGTA plus 100 microM 3,4,5-trimethoxybenzoic acid 8-(diethylamino)octyl ester (TMB-8, intracellular Ca2+ antagonist), and 5 microM cytochalasin B also produced cellular retraction, but these changes were not blocked by chloride channel inhibition. In the presence of 0.1 mM ouabain plus 0.1 mM bumetanide, 36Cl- uptake was decreased by isoproterenol plus isobutylmethylxanthine while its efflux was enhanced. N-Phenylanthranilic acid inhibited the stimulated efflux. We conclude that cyclic AMP induces a configurational change of endothelial cells that is related to Cl- efflux from the cells; the cellular effects may play a role in vascular function.

Animals↗
PubMed1990

Cauda equina neurinoma associated with normal pressure hydrocephalus--case report.

A 45-year-old male was hospitalized because of gait disturbance, urinary incontinence, and memory disturbance. A computed tomographic (CT) scan revealed dilatation of the cerebral ventricles, and a metrizamide CT scan showed reflux into all ventricles. Cerebrospinal fluid obtained at the time of metrizamide CT was highly xanthochromic. Myelograms demonstrated a tumor between the inferior portion of the fifth lumbar vertebra and that of the second sacral vertebra. After removal of a spinal tumor involving nerve fibers at the cauda equina, his symptoms disappeared and the spinal fluid protein normalized. Three months after surgery, a CT scan revealed reduction of cerebral ventricular size. There are 10 reported cases of spinal tumors resulting in normal pressure hydrocephalus. All these and present cases involved protein in the spinal fluid, which might have been the cause of the hydrocephalus.

Cauda Equina↗
PubMed1990

Intracranial and intraspinal dissemination from pineal yolk sac tumor treated by PVB therapy--case report.

A 15-year-old male was admitted because of diplopia and persistent headache. Postcontrast computed tomography (CT) revealed a homogeneously enhanced large mass, 3 x 4 cm in size, in the pineal region and moderate obstructive hydrocephalus. A right ventriculoperitoneal shunt was installed. At that time, the serum alpha-fetoprotein (AFP) level increased to 23,036 ng/ml, but the level of serum beta-subunit of human chorionic gonadotropin was less than 0.2 ng/ml. These data indicated the tumor to be a pure yolk sac tumor. Following cisplatin-vinblastine-bleomycin (PVB) therapy and whole-brain irradiation (50 Gy), the tumor disappeared on CT, although the AFP level did not return to normal. Eight months after the completion of initial therapy, he had lumbago. Spinal magnetic resonance imaging revealed a metastatic mass at the L5-S2 levels, which was subtotally removed and histologically diagnosed as yolk sac tumor. Postoperative local irradiation (30 Gy) was performed. Seven months after the operation, spinal dissemination at the Th7 level occurred and, 1 month later, intracranial dissemination in the left cerebellopontine angle was detected. He died 25 months after the first admission. PVB therapy did not prevent spinal dissemination in this case.

Adolescent↗
PubMed1990

A clinical study of percutaneous nephroureterolithotripsy.

Percutaneous nephroureterolithotripsy was performed a total of 309 times in 225 renal units of 209 patients with upper urinary tract calculi, a mean of 1.37 times per kidney. Residual calculi, 5 mm or greater in diameter, were observed in 3 of 100 kidneys (3%) with single calculi, 12 of 102 kidneys (11.8%) with multiple calculi, and 8 of 23 kidneys (34.8%) with staghorn calculi. The number of sessions, duration of nephrostomy, and the frequency of residual calculi were significantly higher in problem calculi, such as multiple, large and staghorn calculi, than in other calculus types. A combination of percutaneous nephroureterolithotripsy and extracorporeal shock wave lithotripsy was considered to be necessary to improve the efficiency of lithotripsy. Complications included a transient fever, bleeding requiring transfusion and perforation of the renal pelvis in a small number of cases, but these were all mild and could be managed by conservative treatment, alone.

Adolescent↗
PubMed1990

Effects of cytosine methylation at restriction sites on deoxyribonucleic acid (DNA) typing.

The effects of endogenous 5-methylcytosines on deoxyribonucleic acid (DNA) fingerprints were studied. Analysis with methylation-sensitive restriction endonuclease Sau3AI and its methylation-insensitive isoschizomer MboI showed some differences in the patterns generated as a result of 5-methylcytosines at the recognition sites. Moreover, a few bands of sperm DNA did not match those of blood DNA from the same individual, a phenomenon only observed in the digests of methylation-sensitive endonucleases. These findings indicate the unsuitability of methylation-sensitive restriction endonucleases for DNA fingerprinting and other forms of DNA typing, because of the tissue-specific status of the methylation.

5-Methylcytosine↗
PubMed1990

[Two cases of rheumatoid arthritis complicated with vasculitis-induced ischemic enterocolitis].

Episodes of catastrophic entero-colitis associated with mesenteric vascular insufficiency in patients with rheumatoid arthritis(RA) have rarely been recorded thus far. We herein report two cases of RA complicated with severe attacks of entero-colitis presumably due to mesenteric vasculitis. Surgical intervention was necessary in the first case, while the second patient recovered well only through conservative therapy. Case 1: A 74-year-old man with history of RA since 1985 started to complain of abdominal discomfort and nausea early in February, 1989. On February 12, Episodes of tarry stool developed. Rapid down-hill clinical course prompted laparotomy under the clinical diagnosis of peritonitis. Ischemic changes were observed at the ileum end, the entire length of which was 120 cm orally from the cecum. The site was resected. Multiple linear and aphthoid ulcer lesions were discovered throughout the entire lumen. Histopathologically, evidence of necrotizing vasculitis such as fibrinoid necrosis and mural thrombi was demonstrated in small arteries of the submucosal layer underlying the ulcer lesion. Case 2: A 63-year-old woman who had been suffering from RA since 1980 noticed the onset of nausea, abdominal pain and bloody diarrhea in July, 1989. Colonoscopy examination revealed multiple linear and aphthoid ulcers in the sigmoid colon which was presumed to be due to ischemia. Laboratory evaluation at that time demonstrated hypocomplementemia, positive circulating immune complex and high titer of anti-DNA antibody. Corticosteroid therapy with moderate dose was successful in alleviation of all the abnormal findings and the patient fully recovered three months after her initial GI episode.

Aged↗
PubMed1990

Immunohistochemical demonstration of serotonin neuron system in the central nervous system of the Japanese dogfish, Scyliorhinus torazame (Chondrichthyes).

The distribution of serotonin immunoreactivity in the brain of the Japanese dogfish (Scyliorhinus torazame) was studied with the peroxidase-antiperoxidase immunohistochemical method with serotonin antiserum. The somata of the serotonin neurons were located in the raphe regions of the brain stem and the spinal cord. A small number of serotonergic neurons were also distributed as cerebrospinal-fluid contacting neurons in the organum vasculosum hypothalami (OVH) and the paraventricular organ (PVO). These neurons were classified into nine groups (S1-S9): spinal cord (S1), rhombencephalon (S2-S6), mesencephalon (S7), and prosencephalon (OVH, S8 and PVO, S9). Processes of the serotonin neurons were widely distributed in the central nervous system, forming dense networks in various regions. The highest concentrations of these fibers were in the dorsal area of the vagal lobe, the nucleus isthmi, the tuberculum posterium, the distal part of the PVO, and the dorsal regions of the olfactory tubercle.

Animals↗
PubMed1990

[Structural analysis of abnormal hemoglobin by the polymerase chain reaction (PCR) of genomic DNA].

Determination of the primary structure of abnormal Hbs on the basis of DNA sequencing of the globin gene obtained from a carrier of abnormal Hb was performed. DNA obtained from the leukocytes of the peripheral blood was amplified by the polymerase chain reaction (PCR) using the proper amplification primer set. Amplified DNA was digested with two different restriction endonucleases and cloned to vector M 13 mp 18 or mp 19, which had been digested with the same enzymes. DNA sequencing was done by the dideoxy chain termination method using T 7 DNA polymerase, and the abnormal Hbs whose primary structure was determined were as follows: Hb Fukuoka [beta 2 His(CAC/T)----Tyr(TAT)], Hb Machida [beta 6 Glu(GAG)----Gln (CAG)], Hb Hope [beta 136 Gly(GGT)----Asp(GAT)], Hb Hiroshima [beta 146 His(CAC)----Asp(GAC)] and Hb Kodaira [beta 146 His(CAC)----Gln(CAA)]. This method for determining the primary structure of abnormal Hbs might be more effective than the ordinary method, which involves amino acid analysis and amino acid sequencing of the abnormal peptide obtained from abnormal Hb.

DNA↗
PubMed1990

[Development of coronary atherosclerosis in the elderly].

The role of aging, hypertension and plasma cholesterol in the development of coronary atherosclerosis was examined in 3569 consecutive autopsy cases, aged 60 to 99 years, at the Tokyo Metropolitan Geriatric Hospital. The prevalence of coronary atherosclerosis increased with aging. Both systolic and diastolic hypertension were related to the prevalence of coronary atherosclerosis. High plasma cholesterol (230 mg/dl) was related to increased prevalence of coronary atherosclerosis. This effect was observed in a hypertensive group, but not in a normotensive group. To define the effect of hypertension on vascular diseases, endothelial cells from spontaneously hypertensive rats (SHR) were obtained and characterized in terms of cellular response. Cellular Ca2+ level in response to A23187 was significantly enhanced in SHR compared to normotensive Wistar-Kyoto rats (WKY). Thus, aging, hypertension and high plasma cholesterol are risk factors for coronary artery atherosclerosis in the elderly.

Aged↗
PubMed1990

[A case of ganglioglioma with choked disc].

A case of ganglioglioma associated with choked disc is reported. A 19-year-old girl was admitted to our hospital because of blurred vision. Neurologically, the patient had nothing but choked disc. The CT showed a large cystic mass with calcification in the left parieto-occipital lobe. The MRI revealed that the cyst was delineated by a membrane and that its dorsal side was solid, showing enhancement by Gd-DTPA. Cerebral angiography showed no tumor stain. Left parieto-temporo-occipital craniotomy was performed and the tumor was removed subtotally. Histopathological examination demonstrated the typical pattern of ganglioglioma. The most common symptom of ganglioglioma is convulsions. Symptoms of increased intracranial pressure have been reported sporadically in the literature. It was clinically noted that the cause of the increased intracranial pressure in this patient was enlargement of the cyst associated with ganglioglioma.

Adult↗