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S Iida

Publications and source records attributed to S Iida.

At least 361 records · Page 20Linked to original sources

Sequence relations among the IncY plasmid p15B, P1, and P7 prophages.

Electron microscopic analysis of heteroduplex molecules between the 94-kb plasmid p15B and the 92-kb phage P1 genome revealed nine regions of nonhomology, eight substitutions, and two neighboring insertions. Overall, the homologous segments correspond to 83% of the P1 genome and 81% of p15B. Heteroduplex molecules between p15B and the 99-kb phage P7 genome showed nonhomology in eight of the same nine regions; in addition, two new nonhomologous segments are present and P7 carries a 5-kb insertion representing Tn902. The DNA homology between those two genomes amounts to 79% of P7 DNA and 83% of p15B. Plasmid p15B contains two stem-loop structures. One of them has no equivalent structure on P1 and P7 DNA. The other substitutes the invertible C segments of P1 and P7 and their flanking sequences including cin, the gene for the site-specific recombinase mediating inversion.

Coliphages↗

Insertion element IS1 can generate a 10-base pair target duplication.

Transposable element IS1 is known to generate mainly 9-bp and occasionally 8-bp target duplications upon transposition. We have isolated a plasmid pBR322 derivative having IS1 inserted into a site between the promoter and the structural gene for tetracycline resistance. DNA sequence analysis revealed that integration of this IS1 resulted in a 10-bp target duplication.

Base Composition↗

Terminal inverted repeats of prokaryotic transposable element IS186 which can generate duplications of variable length at an identical target sequence.

The insertion element IS186, which resides in the chromosome of Escherichia coli K-12, is 1338 bp long. Its termini represent 23-bp perfectly inverted repeats, but a variant carries a mismatch at position 23. IS186 transposes preferentially into G + C-rich sequences and generates target duplications of variable length, even at the same integration site.

Base Composition↗

Acceleration of the rate of fluorescence decrease by high concentrations of ATP under the condition of accumulation of ADP-sensitive phosphoenzyme in Na+,K+-ATPase.

Addition of up to 300 microM ATP in the presence of 2 M NaCl with MgCl2 to pig kidney Na+,K+-ATPase treated with N-[p-(2-benzimidazolyl)phenyl]maleimide seemed to be insufficient to saturate the rate of the fluorescence decrease. However, both the extent of the decrease and the amount of phosphoenzyme at a steady state were saturated below 20 microM ATP. Addition of Mg2+ with Na+ to the enzyme preincubated with 20 to 600 microM ATP gave nearly the same rate constant, which was below 50% of that obtained by adding 300 microM ATP to the Na+-form enzyme in the presence of Mg2+. High concentrations of ATP affected neither the rate of light-scattering change (Taniguchi, K. et al. (1986) J. Biol. Chem. 261, 3272-3281) after ADP-sensitive phosphoenzyme formation (E1P) nor that of the breakdown of E1P. A stoichiometric amount of [32P]Pi was liberated from [32P]E1P. The data suggested that ATP did not bind to E1P in such a way as to increase the extent of phosphorylation further or to accelerate dephosphorylation. The data also suggested that the reason for the large difference in the apparent affinity of ATP as evaluated from the rate and the extent of fluorescence change is the large dissociation constant for ATP of a Michaelis complex.

Adenosine Diphosphate↗

Calcium binding to calmodulin. Cooperativity of the calcium-binding sites.

The effects of Mg2+ ion, pH, and KCl concentration on Ca2+ binding to calmodulin were studied by using a Ca2+ ion-sensitive electrode. The Ca2+ ion affinity of calmodulin increased with increasing pH or decreasing KCl concentration. Cooperativity between the Ca2+-binding sites was observed, and increased with decreasing pH or increasing KCl concentration. Free Ca2+ ion concentration was decreased by adding MgCl2 ion at low Mg2+ concentration and increased at higher concentrations in the presence of small amounts of Ca2+ ion. The decrease of free Ca2+ ion concentration by Mg2+ ion strongly suggests cooperativity between the Ca2+-binding sites, and it is difficult to explain the decrease in terms of the ordered binding models previously proposed. These results can be explained by a simple model which has four equivalent binding sites that bind Ca2+ and Mg2+ competitively, and showing cooperativity when either Ca2+ or Mg2+ is bound. Mg2+ ion binding to calmodulin was measured in the presence or absence of Ca2+ to confirm the validity of this model, and no Mg2+-specific site was observed.

Allosteric Site↗

Renal hypouricaemia in a patient with 48,XXYY syndrome.

Studies on hypouricaemia observed in a patient with 48,XXYY syndrome revealed an abnormality in renal urate handling. His renal urate clearance was abnormally increased. Inosine administration and provocative tests using probenecid and pyrazinamide identified an isolated renal tubular abnormality with increased urate secretion. Since the serum urate in his brother with a normal sex chromosome constitution was also low, the association of renal hypouricaemia and 48,XXYY syndrome in this patient is probably coincidental. Although the brother was not investigated, these siblings may be a previously unreported case of familial hypouricaemia due to isolated renal hypersecretion.

Adult↗

[Effect of hemodialysis on left and right ventricular function--evaluation using electrocardiogram gated radionuclide ventriculography].

Eighteen outpatients with chronic renal failure undergoing hemodialysis (HD) were studied. Immediately before and after HD, the left and right ventricular function measured by electrocardiogram gated radionuclide ventriculography (RNV). By HD, body weight changed 58.6 +/- 7.50 kg to 57.2 +/- 6.80 kg and BUN level changed 67.9 +/- 29.00 mg/dl to 37.1 +/- 18.96 mg/dl and creatinine level changed 11.3 +/- 3.90 mg/dl to 6.8 +/- 2.48 mg/dl. Before HD, cardiac output was 8.08 +/- 1.50 l/min and cardiac index was 5.00 +/- 0.87 l/(min m2). Left ventricular function improved (LVEF changed 60.4 +/- 6.85% to 64.2 +/- 8.7%, LVEF/LVET changed 0.237 +/- 0.048%/ms to 0.254 +/- 0.021%/ms) between before and after HD, but there was not significant difference. Right ventricular function improved (RVEF changed 41.2 +/- 8.00% to 50.0 +/- 11.96, RVEF/RVET changed 0.167 +/- 0.028%/ms to 0.209 +/- 0.059%/ms) between before and after HD, and there was significant difference (p less than 0.05).

Adult↗

[Embryonal carcinoma (Higuchi, Kato) of the ovary, clinical analysis and recent improvement of treatment using alpha FP as a tumor marker].

Forty-one cases of embryonal carcinoma were analyzed from a clinico-pathological point of view. The clinical stages of the patients were: 21 cases in stage I, 8 in stage II, 11 in stage III and 1 in stage IV. Survival curves were compared in accordance with clinical stages. A statistically significant difference was demonstrated between stages I and III, and a significant difference was demonstrated between stages I and II. Embryonal carcinoma in a narrow sense and yolk sac carcinoma were compared in survival curve but there were no significant differences between the two. Cases were divided into two that were pure embryonal carcinoma and embryonal carcinoma with other constituent mixtures. A comparison of these two showed that the mixed type had a better survival curve than the pure type. Effects of treatment in two different periods were compared patients who were treated in 1971-1979 belong to the 1st period group and those treated in 1979-1985 to the 2nd period group. A comparison of these two showed a much better survival curve in the 2nd period group. This difference can be attributed partly to a VAC combination chemotherapy and its maintenance for two years and partly to improvements in the operating technique such as added omentectomy and or the introduction of a second look operation. By measuring alpha FP over the whole clinical course, alpha FP was shown to be a good tumor marker reflecting the patient's condition and aggravation of the patient's condition frequently occurred around or somewhat after 15 weeks after primary surgery.

Adolescent↗

[Experience with imipenem/cilastatin sodium in the field of obstetrics and gynecology].

Fundamental and clinical studies on a new carbapenem antibiotic, imipenem/cilastatin sodium (MK-0787/MK-0791), were carried out in the field of obstetrics and gynecology. The following results were obtained. The concentration of MK-0787 in uterine tissue was 3.5 approximately 8.2 micrograms/g at about 30 minutes after an administration of 0.5 g/0.5 g of MK-0787/MK-0791 by a 30-minute intravenous drip infusion. The concentration decreased to less than 0.5 microgram/g by approximately 3 hours. The level of MK-0787 in the pelvic dead space exudate reached a peak of 24.0 +/- 4.4 micrograms/ml at 1 hour after an administration of MK-0787/MK-0791 0.5 g/0.5 g and was higher than the plasma level at 1 hour. The level in the pelvic dead space exudate was 2.0 +/- 0.8 microgram/ml at about 6 hours. The MK-0787/MK-0791 was administered to 4 patients with gynecologic infections (2 patients with pelvic peritonitis, 1 patient with salpingitis, 1 patient with a vulvar abscess). The clinical efficacy was good in all 4 patients. Neither adverse effects nor abnormal laboratory findings were observed. It appears that MK-0787/MK-0791 is a safe and useful antibiotic for the treatment of obstetrical and gynecological infections.

Abscess↗

Clinical and portal hemodynamic features in cirrhotic patients having a large spontaneous splenorenal and/or gastrorenal shunt.

Clinical and portal hemodynamic features in 28 cirrhotic subjects with a large spontaneous spleno- and/or gastrorenal shunt were studied in comparison with 30 control cirrhotic cases without such collaterals. Forty-six percent of the former had chronic hepatic encephalopathy, but none of the latter was encephalopathic. These patients with large renal shunts were divided into those with and those without encephalopathy. Large esophageal varices were significantly less common in patients with a large shunt and encephalopathy compared with those who had a large shunt but no encephalopathy, and the control. But there was no significant difference of past variceal bleeding among these three groups. In all those with encephalopathy, part of superior mesenteric venous blood was shunting through these collaterals into the left renal vein or inferior vena cava, but the same was not demonstrable in patients with a large shunt and no encephalopathy and control cirrhotics. In the chronic encephalopathic, portal venous flow was estimated to be less than one-half of that in control cirrhotics, and the portion of superior mesenteric venous blood that was flowing hepatofugally through a large shunt into the left renal vein seemed about the same or greater than the portal venous flow. Thus, a large spontaneous spleno- and/or gastrorenal shunt might prevent development of large esophageal varices but not variceal hemorrhage and it increased a risk of chronic hepatic encephalopathy.

Adult↗

Portographic opacification of hepatic veins and (anomalous) anastomoses between the portal and hepatic veins in cirrhosis--indication of extensive intrahepatic shunts.

On the premise that extensive intrahepatic portal-venous anastomoses known to occur in cirrhosis would be demonstrated by contrast medium directly placed in the portal vein, percutaneous transhepatic portograms were analyzed in 82 patients with liver cirrhosis in relation to the estimated degree of shunting. The degree of intrahepatic shunt was measured during transhepatic portography using 99mTc-macroaggregated albumin. Hepatic veins began to opacify at 4 to 10 s after the start of injection of contrast medium during portography in 20 patients with cirrhosis who had intrahepatic shunt indices of 58.5 +/- 18.5%, but it was not visualized in 62 patients with cirrhosis whose shunt indices were 19.9 +/- 14.1%. Anomalous large anastomoses of 1 or 2 mm in size between the right portal vein and the right hepatic vein were clearly visualized during portography in 18 of 20 patients in whom the hepatic vein was opacified. Frequency and time of beginning opacification of the hepatic vein were closely correlated with the degree of intrahepatic shunt. Thus, opacification of the hepatic vein and abnormal anastomoses between the portal and hepatic vein systems in an early phase of portography indicates extensive intrahepatic shunts.

Hepatic Veins↗

Long-term survival of patients with hepatocellular carcinoma combined with liver cirrhosis. Report of two patients.

Two patients with hepatocellular carcinoma combined with liver cirrhosis lived more than 5 years after hepatic resection. One patient with liver cirrhosis combined with schistosomiasis japonica survived 5 years and 2.5 months after left lobectomy and died of liver failure. Two recurrent tumors, each 1 cm in diameter, were present in the remaining lobe but were not responsible for death. Another patient is well 9 years and 2 months after extended right lobectomy. The tumor was bulky, and the resected specimen was 2800 g in weight. These facts show that patients with hepatocellular carcinoma combined with liver cirrhosis can survive for a long period even if a large tumor is involved.

Adult↗

Characterization of a major form of rat hepatic microsomal cytochrome P-450 induced by isoniazid.

Cytochrome P-450j has been purified to electrophoretic homogeneity from isoniazid-treated adult male rats; and this enzyme appears to be a major protein induced in hepatic microsomes after administration of isoniazid, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The hemoprotein has a minimum molecular weight of approximately 51,500, and the ferrous-carbonyl complex of cytochrome P-450j has a Soret maximum at 451-452 nm. The oxidized heme iron appears to be predominately in the high spin state as deduced from the Soret maximum at 395 nm. Ethylisocyanide binds to ferrous cytochrome P-450j to yield spectral maxima at approximately 458 and 430 nm with a resultant 458/430 ratio of 0.7 at pH 7.4. Cytochrome P-450j has no measurable catalytic activity for the metabolism of benzo[a]pyrene (3- and 9-hydroxylation), hexobarbital, testosterone, and 5 alpha-androstane-3 alpha,17 beta-diol-3,17-disulfate. Low, but detectable, catalytic activity is obtained for the metabolism of 7-ethoxycoumarin, benzphetamine, p-nitroanisole, zoxazolamine, and 2-hydroxylation of 17 beta-estradiol. In contrast, cytochrome P-450j effectively catalyzes p-hydroxylation of aniline with a turnover of 12.7 nmol/min/nmol cytochrome P-450j. Hydroxyl radical scavengers, Fe-EDTA, superoxide dismutase, and catalase have no effect on aniline p-hydroxylation catalyzed by cytochrome P-450j. Cytochrome P-450j is distinct from nine other rat hepatic microsomal cytochromes P-450 (P-450a-P-450i) previously purified in this laboratory, as well as different isozymes described by other investigators, based on several parameters including minimum molecular weight, spectral properties, and catalytic activity. In Ouchterlony double diffusion plates, antibodies against cytochromes P-450a-P-450f show no cross-reaction with cytochrome P-450j. Structural differences among cytochromes P-450a-P-450j are apparent from the NH2-terminal sequence of cytochrome P-450j, as well as the electrophoretic profiles of proteolytic digests of the hemoproteins.

Amino Acids↗

Growth hormone-producing pituitary adenoma with crystal-like amyloid immunohistochemically positive for growth hormone.

Growth hormone (GH)-producing pituitary adenoma from a 50-year-old acromegalic female was studied histochemically, immunohistochemically and electron microscopically. The adenoma was characterized by numerous crystal-like amyloid bodies of 5 to 40 micron in diameter. In the periphery of the crystal-like amyloid, bundles of amyloid fibrils were closely associated with deep invaginations of adenoma cells. The adenoma cells had numerous vesicles and vacuoles filled with amyloid fibrils, some of which were continuous with extracellular space. The crystal-like amyloids, as well as the adenoma cells, were immunohistochemically positive for GH. It might be possible that disorder of hydrolysis of "prohormone," from which GH is elaborated, is responsible for the amyloid production, and that amyloid discharge is accompanied with immunoreactive GH.

Acromegaly↗