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Biomedical subjects

K Aoki

Publications and source records attributed to K Aoki.

At least 793 records · Page 44Linked to original sources
PubMed1985

[Pharmacokinetics and clinical studies on cefminox in the field of obstetrics and gynecology].

Cefminox (CMNX, MT-141), a new cephamycin antibiotic, was studied in the field of obstetrics and gynecology, and the following results were obtained. The absorption and the penetration of CMNX into pelvic dead space exudate were good. The mean peak serum level after single intravenous injection was 190.8 micrograms/ml. The level in pelvic dead space exudate reached a peak of 36.6 micrograms/ml 4 hours after an intravenous injection of 1 g and 6.5 micrograms/ml after 12 hours, thus the level over MIC against main pathogenic organisms was maintained for a long time. CMNX was administered against gyneco-obstetrical infections such as intrauterine, intrapelvic, adnexal infections and postoperative wound infections with daily dose of 2 g and was effective in 11 cases out of 12 cases (91.7%), and 81.8% of bacteriological effect was obtained. No side effect was observed. From the above results the usefulness of CMNX in the field of obstetrics and gynecology was suggested.

Adolescent↗
PubMed1985

[Ileal artery aneurysm: a case report and review of literature].

In a 70-year-old Japanese male who had a history of a radical operation of ruptured descending thoracic aortic aneurysm, the ileal artery aneurysm developed asymptomatically during postoperative follow up period. The aneurysm was about 10 by 4.5 by 4 cm in size and atherosclerosis microscopically. This case seemed to be the 20th case of superior mesenteric artery aneurysm and the 4th case of ileal artery aneurysm reported in Japan. Furthermore, this may be the first report of ileal artery aneurysm associated with thoracic aortic aneurysm in Japanese and English literature.

Aged↗
PubMed1984

Effect of amino acid residues on conformational stability in eight mutant proteins variously substituted at a unique position of the tryptophan synthase alpha-subunit.

To elucidate the role of individual amino acid residues in stabilizing the conformation of a protein, the stabilities of wild-type tryptophan synthase alpha-subunit from Escherichia coli and seven mutant proteins substituted by single amino acid residues at position 49, which is buried in the interior of the protein, were compared. The mutant proteins have Gln, Met, Val, Tyr, Leu, Ser, or Lys in place of Glu in the wild-type protein. The dissociation constant, pK, of the Glu residue at position 49 for the wild-type protein was determined to be 7.5 from a titration curve obtained by comparison of two-dimensional isoelectric focusing electrophoresis of the wild-type and mutant proteins. Our results indicate that 1) the conformational stabilities of the proteins studied increase linearly with hydrophobicity of the substituting residues (except Tyr), with the coefficient of this linear dependence being 2.0, 3.4, or 1.3 at pH 5.5, 7.0, or 9.0, respectively; and 2) Lys or Glu at position 49 serve as a destabilizing factor when ionized.

Amino Acids↗
PubMed1984

A quantitative genetic model of two-policy games between relatives.

Equations are derived for the change per generation of the population mean of the probability that an individual adopts a policy 1 as opposed to a policy 2 in a behavioral interaction between two diploid individuals of the same generation in which two policies are possible. The probability is assumed to be a quantitative genetic trait determined by many additively acting genes of small effects and an independent environmental component. Equations are derived for the case that interactions occur at random between all members of the population and also for the case that interactions occur between relatives of the same average degree of relatedness. It is assumed that each group of relatives and the number of such groups is sufficiently large. For a quantitative genetic trait with the additional assumption of unlinked loci the latter equation can be heuristically derived from the first by substituting the corresponding inclusive fitness effects. When per locus selection coefficients are small and linkage equilibrium holds, the average degree of relatedness can be equated approximately with Wright's coefficient of relationship. Thus, the quantitative genetic model provides a genetic basis for the inclusive fitness approach toward games between relatives. By contrast, in a monogenic system with major gene effects we obtain substantially different results which contradict those obtained by the inclusive fitness approach in game theory. Applications are made to the hawk-dove game, and the simple and iterated forms of the prisoner's dilemma.

Altruism↗
PubMed1984

Follow-up study of a nation-wide neonatal metabolic screening program in Japan. A collaborative study group of neonatal screening for inborn errors of metabolism in Japan.

A nationwide neonatal screening program for phenylketonuria (PKU), maple syrup urine disease (MSUD), homocystinuria, histidinemia and galactosemia was started in Japan in 1977. The total number of infants screened had reached 6,311,754 by March, 1982. A follow-up study revealed the incidence of the disease in Japan: 1/108,823 for PKU; 1/450,840 for hyperphenylalaninemia (HPA); 1/1,577,939 for biopterin deficiency; 1/525,980 for MSUD; 1/1,051,959 for homocystinuria; 1/8,371 for histidinemia, and 1/788,969 for galactosemia type 1. The incidences of PKU, HPA, homocystinuria, and galactosemia (type 1) were found to be markedly low in Japan as compared with those in Caucasian countries. There was no great difference in the incidence of MSUD between both. On the other hand, the incidence of histidinemia was higher in Japan. It was found that most of the patients with PKU, HPA, MSUD, homocystinuria, or galactosemia are developing normally due to the early initiation of dietary treatment. These results clearly indicate that the neonatal mass screening program plays a great role in preventing the occurrence of handicapped children.

Biopterins↗
PubMed1984

Effects of background and spatial pattern on incremental sensitivity of catfish horizontal cells.

Incremental sensitivity of cones and horizontal cells was examined in the retina of the channel catfish (Ictalurus punctatus). In horizontal cells, steady full-field background illumination made the spot-evoked dynamic response larger and faster. The "enhancement" of incremental sensitivity was maximal at background levels of 20-50 microW/cm2. Similar changes in response were obtained by enlarging the diameter of the test spot (to 4 mm) without background illumination. In cones, no such enhancement with background was observed and small (0.4 mm) and large (4.0 mm) spots produced similar responses. Similar enhancement by a steady background has been observed also in the proximal neurons of catfish retina.

Animals↗
PubMed1984

An international study of smoking and bladder cancer.

The effects of smoking cigarettes and other forms of tobacco on the development of cancer of the lower urinary tract (bladder cancer) were evaluated in Boston, Massachusetts, Manchester, United Kingdom and Nagoya, Japan. Population-based series of incident cases and controls were identified and interviewed in each area. The present analyses were based on 592 cases and 533 controls in Boston, 553 cases and 731 controls in Manchester, and 290 cases and 588 controls in Nagoya. Smokers of cigarettes had about twice the incidence of bladder cancer as nonsmokers. In men the strength of the association between cigarette smoking and bladder cancer was similar in the 3 study areas. The strength of the association varied somewhat from area to area among women. Bladder cancer risk increased with frequency of cigarette smoking and with deep inhaling. In Boston men who smoked 2 or more packs of cigarettes per day and inhaled deeply had nearly 7 times the risk of nonsmokers. Ex-smokers had a level of risk between that of current smokers and nonsmokers. However, there was no clear relationship between risk and age at which cigarette smoking began, time since discontinuation among ex-smokers and use of filters. Over-all, there was little difference in bladder cancer risk between men who had and who had not smoked pipes but pipe smoking did appear to be associated with risk among men who had never smoked cigarettes. Cigar smoking was unrelated to bladder cancer.

Adolescent↗
PubMed1984

Group selection for a polygenic behavioral trait: estimating the degree of population subdivision.

For assessing the degree of population subdivision, and therefore the extent to which group selection might favor an altruistic trait, an appropriate measure is Nei's GST, defined by (F0-F)/(1-F). F0 is the probability that two alleles drawn from the same group are identical in state and F is the probability for two alleles drawn at random from the entire population. These probabilities can be assessed from molecular polymorphisms. GST has a number of properties that make it useful for empirical studies. When the mutation rate is small relative to the migration rate and the reciprocal of the group size, GST depends mainly on the absolute number of migrants per generation, moves rapidly to near equilibrium, and is independent of the number of alleles. The relative homogenizing effect of migration in the island and stepping-stone models is not as different as might be expected; one immigrant chosen randomly from the rest of the population is only one to two times as effective as one from a neighboring group, appreciably exceeding 2 only when there are 1000 or more groups. The use of molecular data to estimate the degree of population subdivision may permit testable predictions of the extent of altruistic behavior.

Alleles↗