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Biomedical subjects

S Ueda

Publications and source records attributed to S Ueda.

At least 559 records · Page 31Linked to original sources
PubMed1992

Changes in superoxide dismutase activity in the gastric mucosa of peptic ulcer patients.

A highly sensitive chemiluminescence method for determining superoxide dismutase (SOD) activities in human gastric mucosa obtained by endoscopic biopsy is described. As the chemiluminescence probe, we used Cypridina luciferin analogue (CLA), a very sensitive and specific probe to detect superoxide generated from hypoxanthine-xanthine oxidase system. SOD activity in the gastric mucosa was assayed by the inhibition of CLA-dependent chemiluminescence in highly diluted tissue homogenates. SOD activity was distributed throughout the gastric mucosa. The marginal mucosa of peptic ulcers showed significantly lower SOD activity when the ulcer was in the active stage, and during the healing stage showed high activity when compared to the endoscopically normal adjacent mucosa of the same patients. The preliminary data suggest that enzymatic SOD in the gastric mucosa may play an important role in the pathogenic and healing processes of human peptic ulcers.

Adult↗
PubMed1992

Pharmacokinetics and pharmacodynamics of benazepril in hypertensive patients with normal and impaired renal function.

The pharmacokinetics and pharmacodynamics of benazepril, an angiotensin converting enzyme (ACE) inhibitor, were investigated after administration of a single oral 5-mg dose and 7 more doses on consecutive days to hypertensive patients with normal renal function (NRF) and those with impaired renal function (IRF). The antihypertensive effect of benazepril was observed as early as 30 min after a single dose, and those effects during consecutive dosing were also sustained for 24 h with a lesser diurnal variation in blood pressure (BP). The time to peak (Tmax) and the apparent elimination half-life (t1/2) for benazepril were 0.6-0.7 h and 0.4-0.8 h, respectively. Tmax for its diacid was 1.5-2.4 h in both groups. The area under the plasma concentration-time curve to 24 h (AUC0-24h) for the diacid was significantly greater in the IRF group than in the NRF group. After consecutive dosing of benazepril, AUC0-24h and plasma peak level (Cmax) were significantly increased in the IRF group. Serum ACE activity was markedly suppressed for 24 h after administration, and the inhibition was closely related to plasma diacid levels. A significant inverse correlation was observed between creatinine clearance and the AUC for the diacid. These results suggest that benazepril is rapidly bioactivated to diacid and exhibits rapid onset and long-lasting antihypertensive effects. Dosage reduction might be required to minimize unnecessary drug accumulation in patients with severe IRF.

Administration, Oral↗
PubMed1992

Expansive laminoplasty with reattachment of spinous process and extensor musculature for cervical myelopathy.

Since 1986 we have performed expansive laminoplasty with reattachment of the spinous processes and extensor musculature in cases of cervical myelopathy, to avoid the late postoperative complications of extensive laminectomy. The operative procedure and results are given in detail. Forty cases (24 men, 16 women) were followed for a mean of 28 months. Postoperative results were satisfactory, with no major complications according to the evaluation criteria of the Japanese Orthopaedic Association. No instability or malalignment was seen on postoperative radiographs.

Adult↗
PubMed1992

A VP4 sequence highly conserved in human rotavirus strain AU-1 and feline rotavirus strain FRV-1.

The primary amino acid sequence of the VP4 proteins of human rotavirus strain AU-1 and feline rotavirus strain FRV-1 was deduced from nucleotide sequence analysis of full-length genome segment 4 cDNAs produced by a combined reverse transcription-polymerase chain reaction. The VP4 genes were 2359 nucleotides in length and contained one long open reading frame capable of encoding a protein of 775 amino acids. Strain AU-1 and FRV-1 VP4s were 98.8% similar at both the nucleotide sequence and amino acid level. Given that most of the genome segments of strains AU-1 and FRV-1 formed hybrids under stringent hybridization conditions, the relationship between their VP4 gene sequences is best explained by feline rotavirus being transmitted to human hosts as whole virions relatively recently. Of added interest is that AU-1 and FRV-1 VP4 both exhibit high degrees of similarity (96.0% nucleotide identity and 97.2 to 97.5% amino acid identity) with serotype G1 human rotavirus strain K8 VP4, which is distinct from any other sequenced VP4 allele. This suggests that strain K8 VP4 was derived by natural gene reassortment from a feline rotavirus or a strain AU-1-like human rotavirus.

Amino Acid Sequence↗
PubMed1992

The complete sequence of African horsesickness virus serotype 4 (vaccine strain) RNA segment 5 and its predicted polypeptide compared with NS1 of bluetongue virus.

The complete sequence of RNA segment 5 of the African horsesickness virus serotype 4 (AHSV-4) vaccine strain was determined from cDNA clones inserted into pBR322. The RNA is 1751 bp long (M(r) 1.12 x 10(6)) and contains an open reading frame encoding a protein of 548 amino acids (M(r) 63,122) with a net charge of +0.5 at neutral pH. A comparison of the sequence of AHSV-4 segment 5 with that of segment 6 of bluetongue virus (BTV) serotypes 10 and 17 revealed 49.2% and 48.9% nucleotide similarity, respectively, and 31.4% amino acid similarity. However, AHSV-4 segment 5 has no significant similarity to BTV segment 5. In addition, Northern blot hybridization showed that full-length AHSV-4 segment 5 cDNA cross-hybridized with the corresponding genes of all serotypes of attenuated AHSV.

African Horse Sickness Virus↗
PubMed1992

Synthesis of Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate) from Methanol and n-Amyl Alcohol by the Methylotrophic Bacteria Paracoccus denitrificans and Methylobacterium extorquens.

Strains of two types of methylotrophic bacteria, Paracoccus denitrificans and Methylobacterium extorquens, synthesized the copolyester poly(3-hydroxybutyrate-co-3-hydroxyvalerate) when methanol and n-amyl alcohol were added together to nitrogen-limited medium. The composition of the copolyester differed considerably between the two strains: the copolyester from P. denitrificans was comparatively rich in 3-hydroxyvalerate (3HV). The 3HV content of the copolyester synthesized by this strain increased with increasing concentrations of n-amyl alcohol. Its maximum content was 91.5 mol% under the conditions used. In M. extorquens, the maximum 3HV content was limited to 38.2 mol%. Since n-amyl alcohol served as a substrate for a standard methanol dehydrogenase, the enzyme was proposed to oxidize both methanol and n-amyl alcohol in the first step of copolyester synthesis from these substrates by methanol-grown cells.

Journal Article↗
PubMed1992

Elevated ratio of late measles among subacute sclerosing panencephalitis patients in Karachi, Pakistan.

Subacute sclerosing panencephalitis (SSPE) in Western countries and Japan is found more often in early- than in late-measles sufferers. Recent SSPE findings in Karachi, however, present a different picture. Age at measles contraction was obtained and analyzed for 44 SSPE patients identified in Karachi between 1983 and 1988. The ratios of early- (< 2 years of age) and late- (> or = 2 years of age) measles sufferers among 36 of these patients who had experienced only one attack of measles were 0.33 and 0.67, respectively. This is in striking contrast to the predominance of early measles in the SSPE histories reported in Japan and an number of Western countries.

Age Factors↗
PubMed1992

Study on chronic renal injuries induced by carbon tetrachloride: selective inhibition of the nephrotoxicity by irradiation.

Carbon tetrachloride (CCl4) was intraperitoneally injected into Balb/c mice 4 times at biweekly intervals, and the morphological changes of the liver and kidney were examined during 12 weeks after the last injection. The renal injuries progressed in spite of cessation of CCl4 treatment; microcysts with tubular-cell degeneration were manifest on day 42 after the last injection of CCl4. At the end of the experiment, however, interstitial fibrosis with inflammatory cell infiltration was much more prominent. Glomerular changes with IgG deposits also developed following the tubulointerstitial changes. The CCl4 treatment induced liver damage as well, but it promptly subsided without formation of cirrhosis. The CCl4 nephrotoxicity was completely inhibited by whole body irradiation (200 rad) exposed at each injection of CCl4. In contrast, the hepatic damage was not changed by irradiation. These results seem to indicate etiologic independence of renal and hepatic events induced by CCl4 treatment. It is also suggested that chronic CCl4 nephrotoxicity is mediated, at least in part, by radiosensitive responses of the mice themselves.

Animals↗
PubMed1992

Local control of prostate cancer by intraarterial infusion chemotherapy facilitated by the use of angiotensin II.

Intraarterial infusion chemotherapy with angiotensin II was carried out in 8 prostate cancer patients whose ages ranged from 61 to 77 years. They had stage C or D tumor progression and complained of difficult urination, bone pain or lymphedema caused by intrapelvic tumor infiltration. Endocrine therapy had been done before the infusion therapy but the clinical status showed little change with a persistence of local symptoms. Cis-platinum and doxorubicin were infused with an indwelling catheter into both internal iliac arteries. After the completion of 1-5 courses, 6 of 8 patients responded remarkably in local symptoms. It is thought that intraarterial infusion chemotherapy can be used safely and effectively in elderly patients.

Adenocarcinoma↗
PubMed1992

Thrombotic occlusion of the middle cerebral artery.

BACKGROUND AND PURPOSE: Epidemiological study of middle cerebral artery occlusion is important because the indication for extracranial-intracranial arterial bypass remains in dispute. To help clarify this issue, we investigated the prognosis of thrombotic middle cerebral artery occlusion in Japanese patients. METHODS: We studied 40 patients with thrombotic middle cerebral artery occlusion who were selected on the basis of clinical features, computed tomographic findings, and angiographic findings. Patients with causes of embolism (i.e., cardiomyopathy, valvular heart disease, cardiac arrhythmia, and carotid ulceration) were excluded. The 40 patients were classified into three groups according to the site of middle cerebral artery occlusion: there were 13 patients with occlusion of the proximal portion of the M1 segment, 13 with distal M1 segment occlusion, and 14 with occlusion of the M2 segment. RESULTS: Good collateral circulation was associated with improved outcomes both clinically and by computed tomography in patients with occlusion of the proximal and distal portions of the M1 segment but not in those with M2 occlusion. CONCLUSIONS: It is reasonable to assume that not only collateral circulation but also the site of occlusion plays an important role in the outcome of middle cerebral artery occlusion. Our finding that good collateral circulation improves the outcome for thrombotic occlusion of the proximal and distal M1 segments supports the possible benefits of such surgery.

Adult↗
PubMed1992

Effect of hemodilution on cerebral hemodynamics and oxygen metabolism.

BACKGROUND AND PURPOSE: To evaluate the effects of hemodilution on cerebral hemodynamics and oxygen metabolism in the normal human brain, we measured regional cerebral blood flow, oxygen extraction fraction, oxygen metabolic rate, and regional cerebral blood volume in eight normal volunteers before and after hemodilution using positron emission tomography and oxygen-15-labeled gas inhalation technique. SUMMARY OF REPORT: Hemodilution was accomplished by phlebotomy of 400 ml and drip infusion of 500 ml low molecular weight dextran, which reduced hematocrit from 42.5% to 37.2% and arterial oxygen content from 19.1 to 16.9 ml/dl (both p less than 0.005). It also increased mean cerebral blood flow from 45.2 to 47.7 ml/100 ml/min (p less than 0.025), but decreased tissue oxygen delivery from 8.7 to 8.0 ml/100 ml/min (p less than 0.05) and cerebral blood volume from 4.9% to 4.6% (p less than 0.025) in the overall cortical gray matter. CONCLUSIONS: Our results indicate that hemodilution in the tested range does not improve oxygen transport or tissue oxygenation in the normal human brain, although it increases cerebral blood flow.

Adult↗
PubMed1992

Renin gene expression in the adrenal and kidney of patients with primary aldosteronism.

mRNA levels for renin in the adrenal gland and kidney were measured by ribonuclease protection assay (RPA). Renin mRNA was not detected by RPA in aldosteronoma and kidney tissues obtained from two patients with primary aldosteronism (PA). In these patients, the PRA values, plasma concentrations of active renin (ARC), and total renin (TRC = ARC + prorenin) were below the assay limit (less than 0.03 ng/L.s, 2.5 ng/L, and 10 ng/L, respectively). On the other hand, renin mRNA was recognized by RPA in aldosteronoma and kidney tissues obtained from two other patients with PA treated with 50 mg/day spironolactone for more than 2 months. Their TRC values were 49.8 and 16.6 ng/L, but their PRA and ARC were undetectable. Renin mRNA content was greater in normal adrenocortical tissue and in the normal kidneys obtained from three hypertensive patients with renal cell carcinoma. In these patients, the mean values of PRA, ARC, and TRC were 0.28 +/- 0.03 (mean +/- SD) ng/L.s, 18.4 +/- 7.8 ng/L, and 110 +/- 15 ng/L, respectively. This is the first report of the lack of renin gene expression in aldosteronoma and kidney tissues obtained from untreated patients with PA. Furthermore, treatment with spironolactone resulted in an increase in the levels of renin mRNA in the aldosteronoma and kidney tissues of patients with PA.

Adrenal Cortex↗
PubMed1992

Sequence analysis of replication origin of plasmid pLS11 of Bacillus subtilis IFO 3022.

The structure of a 1.6-kb SphI-HindIII DNA sequence necessary and sufficient for the replication of a 8.6-kb plasmid pLS11 of Bacillus subtilis IFO 3022, which is responsible for gamma-polyglutamate production, has been characterized by using a trimethoprim (Tmp)-resistance gene derived form B. subtilis TTK24 chromosomal DNA as a selective marker. The 1.6-kb DNA sequence contains a rep gene encoding the protein (333 amino acids) essential for initiation of replication and a possible origin of replication. The predicted REP protein of pLS11 has an overall homology with the REP proteins of pUH1 (74.8% identity), pBAA1 (92.8%), and pFTB14 (78.7%) in Bacillus spp., pLP1 (42.1%) and pLAB1000 (36.3%) in Lactobacillus spp., and pUB110 (35.3%) and pC194 (37.4%) in Staphylococcus aureus, but has not any similarity with the REP protein of the staphylococcal plasmid pT181.

Amino Acid Sequence↗
PubMed1992

Siblings of 21-hydroxylase deficiency (non-salt-losing) with aldosterone hypersecretion.

We describe siblings with the non-salt-losing form of 21-hydroxylase deficiency who had hypersecretion of aldosterone and plasma renin activity (PRA). Blood pressure and serum electrolytes in both cases were normal despite the aldosterone hypersecretion. Aldosterone secretion was elevated markedly with ACTH administration and with sodium deprivation and/or volume depletion during ACTH suppression by dexamethasone. With suppression by dexamethasone, aldosterone hypersecretion was decreased with lowering of the steroids proximal to the block in the biosynthetic pathway. However, urinary sodium excretion was decreased. These results suggest that the biosynthetic pathway for aldosterone production was preserved. Furthermore, aldosterone hypersecretion and high PRA may serve to compensate for the sodium loss which results in turn from the overproduction of the sodium-losing steroids, such as progesterone and 17 alpha-hydroxyprogesterone which are aldosterone antagonists.

Adolescent↗
PubMed1992

Positron emission tomographic measurement of acute hemodynamic changes in primate middle cerebral artery occlusion.

Specific hemodynamic changes in acute ischemia were investigated using a middle cerebral artery occlusion primate model and positron emission tomography. The cerebral blood flow (CBF), cerebral blood volume, oxygen extraction fraction (OEF), and cerebral metabolic rate for oxygen were measured 1, 3, and 9 hours after occlusion. OEF showed an increase in ischemic areas, and especially where CBF was below 18 ml/100 gm/min 1 hour after occlusion the OEF increased significantly (0.69 +/- 0.20, p < 0.05). Nine hours after occlusion, the OEF values were lower compared to those 1 and 3 hours after occlusion. Areas where CBF ranged from 18 to 31 ml/100 gm/min showed an increase in OEF at all times (p < 0.05). Clearly, OEF changes remarkably in the acute stage.

Animals↗
PubMed1992

Localized fat collection adjacent to the intrahepatic portion of the inferior vena cava: a normal variant on CT.

We describe a normal focal collection of fat that has the appearance of a mass on CT scans. The fat is adjacent to the intrahepatic portion of the inferior vena cava and is contiguous to the fat around the subdiaphragmatic portion of the esophagus. This finding occurred in 11 (0.5%) of 2227 patients who had CT scans at our institution. The fat collections did not change in size or shape on follow-up CT scans obtained 2 to 29 months later (mean, 14 months). The localized fat collections were at the level of or above the confluence of the hepatic veins and the inferior vena cava, and were medial to the inferior vena cava. They were less than 22 mm in length, oval, and had attenuation values ranging from -113 H to -23 H on unenhanced CT scans. The collections enhanced slightly on scans obtained after contrast administration. T1-weighted (600/15) MR images obtained in three cases showed a high-intensity mass that was contiguous to high-intensity fat around the esophagus, medial to the intrahepatic portion of the inferior vena cava. Our experience suggests that a masslike fat collection adjacent to the intrahepatic portion of the inferior vena cava is a normal variant on CT scans and should not be mistaken for an abnormality.

Adipose Tissue↗