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Biomedical subjects

K Kano

Publications and source records attributed to K Kano.

At least 37 records · Page 2Linked to original sources
PubMed2001

Chiral recognition of dipeptide methyl esters by an anionic beta-cyclodextrin.

Chiral recognition of dipeptide methyl esters by anionic heptakis[6-carboxymethylthio-6-deoxy]-beta-cyclodextrin (per-CO(2)(-)-beta-CD) was studied in D(2)O at pD 7.0 by means of (1)H NMR spectroscopy. The methyl esters of alanylalanine (Ala-Ala-OMe), alanylleucine (Ala-Leu-OMe), alanyltryptophan (Ala-Trp-OMe), glycyltryptophan (Gly-Trp-OMe), valyltryptophan (Val-Trp-OMe), leucyltryptophan (Leu-Trp-OMe), and tryptophylalanine (Trp-Ala-OMe) were used as the dipeptides. The binding constant (K) determined from NMR titration increases in the order Ala-Ala-OMe < Ala-Leu-OMe < Ala-Trp-OMe, suggesting that van der Waals interactions between the host and the guest participate in complexation. Coulomb interactions between the protonated dipeptide methyl esters and the anionic host seem to be another attractive force. Per-CO(2)(-)-beta-CD interacts with the (R,R)-enantiomers of the dipeptide methyl esters more strongly than the (S,S)-enantiomers. Such enantioselectivity corresponds to that for alpha-amino acid methyl esters such as Leu-OMe and Trp-OMe, whose (R)-enantiomers are the preferable guests. The enantioselectivity is mainly dominated by amino acid residue at the C-terminal and chirality at the N-terminal residue plays an assistant role. An asymmetrically twisted shape of the host cavity may be essential for chiral recognition.

Anions↗
PubMed2001

ER-dependent estrogenic activity of parabens assessed by proliferation of human breast cancer MCF-7 cells and expression of ERalpha and PR.

Estrogenic activities of the phenolic preservatives methylparaben, ethylparaben, propylparaben, butylparaben, isopropylparaben and isobutylparaben were examined by assaying estrogen-receptor (ER)-dependent proliferation of MCF-7 cells. All the compounds stimulated the proliferation to about the same level as the maximal cell yield attained with 3x10(-11) M 17beta-estradiol, but at a concentration in the order of 10(5) to 10(7) higher than 17beta-estradiol. The cell-proliferative effects of parabens were completely suppressed by anti-estrogen ICI 182,780. MCF-7 cells treated with butylparaben and isobutylparaben exhibited a decrease in gene expression of ERalpha and an increase in that of progesterone-receptor (PR), but the effects of these parabens were not as prominent as those of 17beta-estradiol. Western blot analysis indicated that these parabens caused a slight decrease in expression of ERalpha protein. Competitive binding to human ERalpha and ERbeta in vitro revealed that the parabens with longer side-chains showed greater affinity for estrogen receptors, and that they had similar relative binding affinity (RBA) values to both ERalpha and ERbeta. RBA values were much smaller than that of diethylstilbestrol. In conclusion, parabens have ER-dependent estrogenic activities, and their effects on the intracellular signaling pathway might be different from that of 17beta-estradiol.

Binding, Competitive↗
PubMed2001

Issues of intervention aimed at preventing prospective surplus of physicians in Japan.

OBJECTIVES: In Japan, regulatory intervention aimed at preventing a prospective surplus of physicians is an important medical issue. The study committees organized by the Ministry of Health and Welfare (MHW) in 1986, 1993 and 1998, concluded that the number of physicians would exceed demand for their services in the future. As a result, the government planned to reduce the number of medical students. However, MHW has not been successful in the intervention so far, as shown by the fact that their initial plan for a 10% reduction in the number of students enrolled in medical school has not been attained. In this paper, we examine why the MHW policy failed. METHODS: We reviewed those forecasts performed by past MHW study committees and examined whether the government policy of controlling physician training was appropriate. Additionally, we did a preliminary projection of specialty-specific demand for physician services as a reference for future physician manpower policies in Japan. RESULTS: We found that both conflicts among various interest groups and a lack of precise projections of physician services hampered the proper formation and implementation of a physician manpower policy in Japan. CONCLUSIONS: It might be necessary to examine the appropriateness of the MHW policy in reducing the overall number of students enrolled in medical schools. As a first step in formulating and implementing a physician manpower policy, we should begin to consolidate the necessary data to conduct precise and proper projections of future physician demand.

Adolescent↗
PubMed2001

New pathway of amine oxidation respiratory chain of Paracoccus denitrificans IFO 12442.

The physiological electron acceptor of quinohemoprotein amine dehydrogenase (QH-AmDH) from Paracoccus denitrificans IFO 12442 was identified by biochemical and electrochemical methods. Of three types of heme c-containing proteins purified together with QH-AmDH from the periplasm of n-butylamine-grown cells, only constitutive cytochrome c-550 was reduced by the addition of QH-AmDH and n-butylamine. Reconstitution of the respiratory chain revealed that cytochrome c-550 mediates the electron transfer from QH-AmDH to the terminal oxidase. This is a new pathway of the amine oxidation respiratory chain of P. denitrificans.

Amines↗
PubMed2001

Systemic effects of transdermal testosterone for the treatment of microphallus in children.

OBJECTIVES: To elucidate the metabolic effects of topical testosterone for the treatment of microphallus in children. METHODS: We administered 5% testosterone ointment to 50 prepubertal boys for the treatment of microphallus, allowing us to observe its metabolic effect on plasma concentrations of testosterone as a marker of transdermally absorbed testosterone, insulin-like growth factor (IGF)-I as a marker of growth hormone secretion status, and osteocalcin as a marker of bone metabolic turnover. RESULTS: Transdermal application of testosterone for 30 days at a dose that affects penile growth increased mean (+/-SD) plasma testosterone concentrations from 7.5+/-5.1 to 31.0+/-8.2 ng/dL (pre- vs. post-treatment, respectively; P<0.01). This was associated with a slight but statistically significant elevation of IGF-I concentrations (117.2+/-76.9 vs. 154.4+/-81.5 ng/mL; P<0.05). No significant change in osteocalcin levels was found. CONCLUSIONS: When using testosterone ointment as a treatment for microphallus, it should be borne in mind that this application has systemic effects.

Administration, Cutaneous↗
PubMed2001

Preliminary report: effect of adrenal androgen and estrogen on bone maturation and bone mineral density.

To clarify the independent physiological roles of adrenal androgen and estrogen on bone growth, we compared the lumbar spine bone mineral density (BMD) in prepubertal girls with virilizing congenital adrenal hyperplasia (CAH) (n = 17) and girls with central precocious puberty (CPP) (n = 18). When BMD was analyzed according to chronologic age, no significant differences were found between CPP and CAH patients. However, when adjusted to bone age, BMD was statistically higher in CAH than in CPP subjects. This finding suggests that adrenal androgen, as well as estrogen, plays an important role in increasing BMD. Adrenal androgen may act on bone not only as androgen, but as estrogen after having been metabolized into an aromatized bone-active compound in peripheral tissues, such as bone and fat. Therefore, adrenal androgen may have a more important role in increasing BMD than previously realized.

Absorptiometry, Photon↗
PubMed2001

DNA damage induced by red food dyes orally administered to pregnant and male mice.

We determined the genotoxicity of synthetic red tar dyes currently used as food color additives in many countries, including JAPAN: For the preliminary assessment, we treated groups of 4 pregnant mice (gestational day 11) once orally at the limit dose (2000 mg/kg) of amaranth (food red No. 2), allura red (food red No. 40), or acid red (food red No. 106), and we sampled brain, lung, liver, kidney, glandular stomach, colon, urinary bladder, and embryo 3, 6, and 24 h after treatment. We used the comet (alkaline single cell gel electrophoresis) assay to measure DNA damage. The assay was positive in the colon 3 h after the administration of amaranth and allura red and weakly positive in the lung 6 h after the administration of amaranth. Acid red did not induce DNA damage in any sample at any sampling time. None of the dyes damaged DNA in other organs or the embryo. We then tested male mice with amaranth, allura red, and a related color additive, new coccine (food red No. 18). The 3 dyes induced DNA damage in the colon starting at 10 mg/kg. Twenty ml/kg of soaking liquid from commercial red ginger pickles, which contained 6.5 mg/10 ml of new coccine, induced DNA damage in colon, glandular stomach, and bladder. The potencies were compared to those of other rodent carcinogens. The rodent hepatocarcinogen p-dimethylaminoazobenzene induced colon DNA damage at 1 mg/kg, whereas it damaged liver DNA only at 500 mg/kg. Although 1 mg/kg of N-nitrosodimethylamine induced DNA damage in liver and bladder, it did not induce colon DNA damage. N-nitrosodiethylamine at 14 mg/kg did not induce DNA damage in any organs examined. Because the 3 azo additives we examined induced colon DNA damage at a very low dose, more extensive assessment of azo additives is warranted.

Amaranth Dye↗
PubMed2001

An electrochemical approach to the studies of biological redox reactions and their applications to biosensors, bioreactors, and biofuel cells.

Enzymatic redox reactions for the oxidation (or reduction) of the substrates use organic dyes or metal complexes as electron acceptors (or donors), which can be regenerated by electrochemical reactions of the compounds at an electrode surface. This type of coupling of the enzymatic reactions with the electrochemical reactions is called bioelectrocatalysis and allows us to measure the enzymatic reactions by an electrochemical method. The enzyme-electrochemical method provides a new technique for investigating a variety of biological redox reactions and for applying the reactions to biosensors, bioreactors, and biofuel cells. The bioelectrocatalysis-based research works are described here. First, a new method of protein redox potential measurements and a novel electrochemical kinetic analysis of oxidoreductase reactions are described. Second, a new methodology of characterizing microbial catalytic activities is presented. In the last, applications to the constructions of biosensors, bioreactors, and biofuel cells are mentioned.

Journal Article↗
PubMed2001

Effects of short photoperiod on the expression of smad2 and smad3 mRNA in Syrian hamster testis.

The testicular localization and expression of Smad2 and Smad3 mRNA involved in the intracellular signal transduction of activin, inhibin and transforming growth factor-beta (TGF-beta) were examined under the influence of long and short photoperiod in Syrian hamsters (Mesocricetus auratus). In situ hybridization detected both Smad2 and Smad3 mRNA in spermatogonia and premeiotic spermatocytes in the active testis exposed to a long photoperiod, as well as in the regressed testis exposed to a short photoperiod. Northern blots showed that Smad2 mRNA was expressed at all stages over long and short photoperiods, whereas Smad3 mRNA was expressed at high levels in the photoperiod-induced regressed testis. The photoperiodic condition would change the balance between Smad2 and Smad3 transcripts in the testis. Thus, intracellular Smad2 and Smad3 might participate in transducing signals from activin, inhibin and TGF-beta in spermatogenetic cells.

Animals↗
PubMed2001

Glycoconjugate in rat taste buds.

The taste buds of the fungiform papillae, circumvallate papilla, foliate papillae, soft palate and epiglottis of the rat oral cavity were examined by lectin histochemistry to elucidate the relationships between expression of glycoconjugates and innervation. Seven out of 21 lectins showed moderate to intense staining in at least more than one taste bud. They were succinylated wheat germ agglutinin (s-WGA). Dolichos biflorus agglutinin (DBA), Bandeiraea simplicifolia lectin-I (BSL-I), Ricinus communis agglutinin-I (RCA-I), peanut agglutinin (PNA), Ulex europaeus agglutinin-I (UEA-I) and Phaseolus vulgaris agglutinin-L (PHA-L). UEA-I and BSL-I showed moderate to intense staining in all of the taste buds examined. They strongly stained the taste buds of the epiglottis, which are innervated by the cranial nerve X. UEA-I intensely stained the taste buds of the fungiform papillae and soft palate, both of which are innervated by the cranial nerve VII. The taste buds of circumvallate papilla and foliate papillae were innervated by the cranial nerve IX and strongly stained by BSL-I. Thus, UEA-I and BSL-I binding glycoconjugates, probably alpha-linked fucose and alpha-D-galactose, respectively, might be specific for taste buds. Although the expression of these glycoconjugates would be related to the innervation of the cranial nerve X, the differential expression of alpha-linked fucose and alpha-D-galactose might be related to the innervation of the cranial nerve VII and IX, respectively.

Animals↗
PubMed2001

Coronary artery disease risk in Chinese type 2 diabetics: is there a role for paraxonase 1 gene (Q192R) polymorphism?

OBJECTIVE: Heredity plays an important role in the predisposition to atherosclerotic coronary artery disease (CAD), and its thrombotic complications. Paraoxonase, a high-density lipoprotein-associated enzyme capable of hydrolyzing lipid peroxides, is presumed to contribute to atherosclerosis and CAD. This study investigates the role of human paraoxonase 1 (PON 1) gene (Q192R) polymorphism in CAD risk among Chinese type 2 diabetic cases. DESIGN: A population-based case-control study of paraoxonase 1 gene (Q192R) polymorphism and the risk of CAD in Chinese type 2 diabetics. METHODS: Subjects included 201 angiographically documented CAD patients with type 2 diabetes and 231 control subjects with type 2 diabetes alone living in central China. Single strand conformational polymorphism (SSCP) analysis was used to screen for PON 1 gene (Q192R) polymorphism. RESULTS: Frequency of the R allele was 21.5% in the CAD patients and 12.0% in the control subjects. The presence of the R allele was significantly associated with risk of CAD (odds ratio (OR)=1.97; 95% confidence interval (CI)=1.36--2.86). CONCLUSION: Frequency of the 192R allele of the human paraoxonase 1 gene may be an independent risk factor for CAD in the Chinese type 2 diabetics studied.

Aged↗
PubMed2001

Age-period-cohort analysis of lung cancer mortality in Japan, 1960-1995.

The mortality data on lung cancer in Japan from 1960 to 1995 was analysed based on an age-period-cohort (APC) model. Though the APC model has an 'identifiable problem' caused by the relationship of age, period and cohort parameters, non-linear components of them revealed their original (separated) effects. They were: (1) non-linear age effects had a peak in 55-59 and 60-64 years old in males and 50-54 in females, (2) non-linear period effects were very small in both genders, (3) non-linear age and period effects were small enough to neglect compared with their linear effects, and (4) there were five parts of trends in Japanese lung cancer mortality in both genders in the non-linear birth cohort effects. The 1961-65 birth cohort effect seemed to increase differently from previous birth years. This trend should be monitored carefully.

Adult↗
PubMed2001

A necessary and sufficient condition of comparability for using standardized mortality ratio (SMR).

A necessary and sufficient condition of comparability for using SMR was studied mathematically by considering the equivalence between SMR and CMF, as CMF was a perfectly comparable index. This condition was expressed by either proportionality of mortality vectors or proportionality of projected person-years to the plane spanned by mortality vectors of reference and index groups. We could obtain another expression of the condition, in which affect of distortions were easily understood, which consist of three factors: distortion of proportionality of mortality, distortion of person-years and similarity of distortions. Our results were applied to study the mortality of biliary tract cancer in Ibaraki Prefecture. Places where absolute difference between CMF and SMR exceeds some criterion (say, 0.15) were Satomi, Ushiboiri, Nihari in males and Gozenyama, Suifu and Asahi in females. All three distortion indices exceeded their upper 95% percentiles in Satomi in males.

Biliary Tract Neoplasms↗
PubMed2001

[The effects of a health promotion program on physical, mental, and dietetic health status in climacteric women].

PURPOSES: The purpose of this study was to evaluate the effects of a six months health promotion program on physical and mental health status assessments in climacteric women. METHODS: Seventy-two women, with a mean (+/- SD) age of 51.3 (+/- 3.1 yr.), body weight of 51.5 (+/- 6.3 kg), and Body Mass Index of 22.4 (+/- 2.4 kg/m2), residing in Tokyo Metropolitan area, participated as subjects in a health promotion program, completing health status assessments. Health promotion was performed once a week, two hours per session, sixteen times. The lecture and exercise program, in the first half, included basic information on diet, exercise and relaxation, and prevention of life-style related disease, and instructions for walking exercise, dancing, and dumbbell exercise. In the latter half, they performed extended walking, stretching, and autogenic training for relaxation. Healthy foods were also supplied. Before and after the program, health status was assessed, with a general medical health check, a questionnaire regarding nutrition, exercise and relaxation activities, and determination of dietary intake based on food records, eating behavior, complaints (CMI, Nichidai stress score) and physical activity levels. RESULTS: After the six months of the program: 1) Total cholesterol levels had decreased significantly, along with both systolic and diastolic blood pressure, body weight and BMI; 2) Major nutrient intake, density of nutrients and eating behavior were improved, with decrease in daily salt intake, and increase significant in daily energy expenditure; 3) Stress scores by the Nichidai stress check were decreased significantly, subjects with higher stress scores at the beginning of programs having marked change, and neurotic tendencies were decreased in CMI categories II-IV. CONCLUSION: These results suggest that, in order to maintain and/or improve the QOL of climacteric women, good dietary habits and physical activities, such as walking, and psychological support are essential. Further long-term investigations of larger populations (middle-aged to elderly) are now necessary.

Climacteric↗
PubMed2001

[Relationship between keeping a companion animal and instrumental activity of daily living (IADL). A study of Japanese elderly living at home in Satomi Village].

OBJECTIVE: The purpose of this study was to clarify the relationship between the companionship of an animal and the level of Instrumental Activity of Daily Living (IADL) of elderly people living at home, and to consequently determine beneficial effects on the overall health of the elderly. METHODS: For this study, 400 elderly people aged 65 years and over were randomly selected from among the 1,345 citizens of Satomi Village, Ibaraki Prefecture. Self-administered questionnaires were mailed to the selected subjects in March of 1999. In the survey, the respondents were asked if they could accomplish all seven IADL activities. Subjects for whom this was the case were classified as having no IADL disability. Elderly who answered "No" for even one were listed as having an IADL disability. Using the existence of an IADL disability as a dependent variable and various factors related to companion animals as independent variables, a logistic regression analysis was performed. RESULTS: Out of the 400 individuals, 84.8% responded. With respect to the possession of a companion animal, the number of participants who never had a companion animal was 115 (35.8%); while 118 (36.8%) possessed a companion animal in the present. With regard to factors relevant to IADL of elderly people, the odds ratio (OR) adjusted for age and sex for participants who owned dogs was 0.53 (95% confidence interval [CI] 0.27-0.99) relative to those who never had a companion animal: The difference was significant. For those respondents who indicated that their companion animals were their best friends, the OR was 0.48 (95% CI 0.23-0.99), and again significant. The OR tended to decrease with increase in the duration of owning a companion animal. CONCLUSION: In this study, owning a dog and everyday contact with the companion animal were related to the IADL of the elderly living at home. It is possible that keeping a companion animal may be linked to better overall health in the elderly.

Activities of Daily Living↗