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Biomedical subjects

H Uchida

Publications and source records attributed to H Uchida.

At least 613 records · Page 34Linked to original sources
PubMed1983

Isolation of conditionally lethal amber mutations affecting synthesis of the nusA protein of Escherichia coli.

Amber mutants (am3 and am4) of Escherichia coli K12 defective in the synthesis of nusA protein (Friedman 1971) were isolated from a strain harboring an amber suppressor (sup-126) that is active only at low temperatures. These mutants grew at low temperature (30 degrees C) but did not grow at temperatures above 38 degrees C. Complementation experiments with plasmids carrying the nusA+ gene and its derivatives or with plasmids carrying the nusA1 or am4 mutation indicated that the mutations am3, am4 and nusA1 affected the same gene function. Analysis of proteins produced by minicells containing a plasmid demonstrated that the plasmid pYN87, which can complement the nusA1 and amber mutations, codes for three bacterial proteins, a truncated nusA gene product (61 K), argG gene product (48 K) and a 21 K dalton protein, and that the am4 mutation affects the synthesis of only NusA protein. lambda Nam7 (and lambda Nam7Nam53) phages could grow on these amber mutants at 32 degrees C but not on the parental strain. Spontaneous temperature-resistant revertants of the amber mutants simultaneously lost the ability to permit lambda Nam7 phage development, indicating that the two phenotypes are due to a single mutation. These results suggest that the nusA gene function is essential for the growth of E. coli, and that the lambda N function is dispensable for phage development if the nusA gene is defective.

Bacterial Proteins↗
PubMed1983

Evaluation by ultrasonography of arterial embolization therapy for hepatocellular carcinoma.

Twelve cases of hepatocellular carcinoma treated by arterial embolization were followed with ultrasonography. Shrinkage of the tumor after the therapy was confirmed in all cases. Echo level reduction in the tumor occurred in 10 cases. High-level reverberation echoes with acoustic shadows emerged in seven cases; however, these echoes were not detected in any cases 3 weeks after the procedure. Echoes were considered either as the consequence of gas produced in the tumor or air trapped in the embolic substance. Ultrasonography, therefore, is an effective technique for the posttherapeutic evaluation of arterial embolization therapy for hepatocellular carcinoma.

Aged↗
PubMed1983

Evaluation of arterial embolization therapy for hepatocellular carcinoma by computed tomography.

Changes in tumor area and the attenuation value determined from computed tomography (CT) slice section of the tumor at its maximum size were investigated in 18 patients with hepatocellular carcinoma who were studied by CT after arterial embolization therapy. The tumor area was reduced in all cases after embolization therapy. Greater than 50% reduction of the tumor area occurred during the follow-up period in 13 cases (87%). In cases evaluated by follow-up CT, the relative attenuation value of tumor to nontumor regions decreased during the initial stage after embolization therapy, but showed a tendency towards greater elevation than in the initial stage, despite tumor reduction. This change in the attenuation value was considered to reflect necrosis and shrinkage of the tumor after embolization therapy. The absence of such changes in nontumor regions supports the use of arterial embolization therapy as an effective, conservative treatment for hepatocellular carcinoma. Follow-up examination by CT of hepatocellular carcinoma after embolization therapy contributes to the post-therapeutic evaluation of tumors and to the determination of the appropriate time for reembolization therapy.

Adult↗
PubMed1983

High density bile in the gallbladder observed by computed tomography.

In eight of 620 computed tomographic examinations of the gallbladder the density of bile was higher than that of the liver. In three the bile density increased and in one it decreased on serial studies. Four of these eight patients had hepatocellular carcinoma.

Absorptiometry, Photon↗
PubMed1983

Immunosuppressive effect of bredinin on cell-mediated and humoral immune reactions in experimental animals.

Bredinin (BR), an imidazole nucleoside isolated from Eupenicillium brefeldianum was previously reported to prolong kidney allograft survival in dogs. The immunosuppressive effect of BR was studied in experimental animals. In beagles, in vitro responses of lymphocytes stimulated by mitogens or allogeneic cells were suppressed by in vitro BR treatment. BR, given in vivo, also showed an inhibitory action against development of delayed hypersensitivity reaction to tubercle bacilli in guinea pigs or against hemagglutinin production following booster SRBC injection in rabbits. Of note may be the fact that BR was found to have an immunosuppressive potency comparable to that of azathioprine and, in addition, to show a decreased hepatotoxicity compared with the latter.

Animals↗
PubMed1983

Mechanism of renal excretion of AM-715, a new quinolonecarboxylic acid derivative, in rabbits, dogs, and humans.

The mechanisms of the renal excretion of AM-715, a synthetic antimicrobial agent, were studied in rabbits, dogs, and humans. In both rabbits and humans, AM-715 clearance was greater than creatinine clearance and was profoundly decreased by the administration of probenecid. Thus, in these subjects, AM 715 was cleared by both tubular secretion and glomerular filtration. In dogs, however, the excretion ratio (close to unity), biological half-life, and stop-flow pattern of AM-715 were not affected by probenecid, indicating that the renal excretion of AM-715 took place mostly through glomerular filtration. These results suggest that renal excretion of AM-715 differs with animal species.

Adult↗
PubMed1983

De novo development of hypercholesterolemia and elevated high-density lipoprotein cholesterol: apoprotein A-I ratio in patients with chronic renal failure following kidney transplantation.

Serum lipids, apoprotein and lecithin-cholesterol acyltransferase activities were studied in 27 renal transplant recipients with stable and normal renal function (serum creatinine 0.16 mM/l or less) sustained for more than 1 year following grafting. Hypertriglyceridemia, which was characteristic of hyperlipidemia in 18 hemodialyzed patients with chronic renal failure, was no longer manifest in transplant recipients. On the other hand, de novo hypercholesterolemia was observed posttransplant with mean serum levels of 5.82 +/- 1.34 versus 5.01 +/- 0.88 mM/l in 575 normal controls. As to the high-density lipoprotein metabolism, the cholesterol content (1.72 +/- 0.56 mM/l) was significantly higher in transplant patients than in hemodialyzed patients (0.82 +/- 0.31 mM/l). In contrast, no variation in apoprotein A-I levels was found between both groups of patients, which produced an elevated high-density lipoprotein cholesterol:apoprotein A-I ratio. Thus, derangement in the serum lipid profile, although qualitatively different, continued to be present following transplantation, and its relevance to the cardiovascular morbidity in these patients remains to be evaluated.

Adult↗
PubMed1983

Comparative study of antitumor activity and immunomodulatory effect of tetrahydro-2-furanyl and tetrahydro-2-pyranyl (1 leads to 3)-beta-D-glucans.

The effects of tetrahydro-2-furanyl- and tetrahydro-2-pyranyl-ethers of (1 leads to 3)-beta-D-glucans from Alcaligenes faecalis var. myxogenes (IFO 13140) on the activities of macrophages and natural killer (NK) cells in either ICR or BALB/c mice were studied. The derivatives with strong antitumor activity against Sarcoma 180 in ICR mice induced higher macrophage tumoricidal activity (greater than 40%) than those with low antitumor activity (less than 20%). All derivatives with high or low antitumor activity augmented NK cell activity. On the other hand, the derivatives which show the high antitumor activity against Meth-A in BALB/c mice enhanced macrophage tumoricidal activity, while those with low or no antitumor activity did not. NK cell activity was activated by the derivatives with or without the antitumor activity. Furthermore, certain derivative which has high antitumor activity against Sarcoma 180 in ICR mice did not increase serum component (LB) in ICR mice. These results indicate that the antitumor activity of the derivatives correlates only with the capacity to cause macrophage activation in vivo.

Adjuvants, Immunologic↗
PubMed1983

[Detection of learning impairment in offspring in reproduction tests].

We examined the ability of learning and its retention employing test with the water T-maze, shuttle box and passive avoidance response (PAR) in offspring from mother rats treated with N-methylnitrosourea (MNU) or chlorpromazine (CPZ). The offspring of MNU-induced learning impairments were detected only in tests with the water T-maze and PAR. On the other hand, CPZ induced impairments were detectable only in tests with the shuttle box and PAR. Thus offspring from mother rats treated with MNU or CPZ showed partially different responses. In retention tests, both MNU and CPZ caused impaired ability in the water T-maze and PAR. In the PAR test, impairment was most clearly detectable. From these results, the PAR test appears to be the most useful method in detection of impairments in learning and retention ability, especially the latter, in the reproduction test of offspring.

Animals↗