Biomedical subjects

Akira Hata

Publications and source records attributed to Akira Hata.

24 records · Page 2Linked to original sources

PubMed2002

Post-traumatic stress disorder in pre-school aged children after a gas explosion.

UNLABELLED: To evaluate the sensitivity of diagnostic criteria for post-traumatic stress disorder (PTSD) in pre-school aged children involved in a gas explosion, post-traumatic symptoms of the children were investigated four times after the accident, immediately, 10 days, 6 months, and 1 year later. Using symptoms at 6 months after the accident, sensitivity of diagnostic criteria was assessed by comparing the fourth edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), and the alternative criteria for infants and young children [10]. In addition, the published Child Post-Traumatic Stress Disorder Reaction Index (CPTSD-RI) and its modified version proposed by us were also evaluated their sensitivity to rate the symptoms. Girls had a tendency to show more post-traumatic symptoms than boys. Although no children met DMS-IV criteria for PTSD, 8 children out of 32 were diagnosed as having PTSD with alternative criteria. With our modified CPTSD-RI, all eight children were decidedly more statistically distinguishable from those without PTSD than with original index. CONCLUSION: our data indicate that the sensitivity of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (4th edition) and the Child Post-Traumatic Stress Disorder Reaction Index in rating symptoms of pre-school aged children is not sufficient. The alternative criteria of the former and modified version of the latter would be the better choice in this age group.

Child↗

PubMed2002

Linkage and association analyses of the osteoprotegerin gene locus with human osteoporosis.

Osteoprotegerin (OPG), a secreted glycoprotein and a member of the tumor necrosis factor receptor superfamily, is considered to play an important role in the regulation of bone resorption by modifying osteoclast differentiation. Overexpression of OPG in mice has been reported to result in osteopetrosis, whereas targeted disruption of OPG in mice has been associated with osteoporosis. Accordingly, OPG could be a strong candidate gene for susceptibility to human osteoporosis. Here, we analyzed whether OPG is involved in the etiology of osteoporosis using both linkage and association analyses. We recruited 164 sib pairs in Gunma prefecture, which is located in the central part of Honshu (mainland Japan), for a linkage study, and 394 postmenopausal women in Akita prefecture, which is in the northern part of Honshu, for an association study. We identified two microsatellite polymorphisms in the linkage study, and six single-nucleotide polymorphisms (SNPs) in the OPG region for the association study. Although, no evidence of significant linkage between OPG and osteoporosis was found, a possible association of one SNP, located in the promoter region of the gene, was identified. A haplotype analysis with the six SNPs revealed that four major haplotypes account for 71% of the alleles in the Japanese population.

Base Sequence↗

PubMed2002

Methylenetetrahydrofolate reductase genotype, vitamin B12, and folate influence plasma homocysteine in hemodialysis patients.

Hyperhomocysteinemia, a well-recognized cardiovascular risk factor, is frequent in hemodialysis (HD) patients. A common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, C-->T substitution at nucleotide 677, is associated with homocysteine (Hcy) level elevation. We examined whether three factors involved in the methionine cycle could influence plasma Hcy concentrations in HD patients: MTHFR polymorphism; vitamin B12, an essential cofactor; and folate, the substrate. In a cross-sectional study, serum vitamin B12, folate, and plasma Hcy were measured and MTHFR genotyping was performed in 534 HD patients. Effects of MTHFR genotypes, vitamin B12, and folate on plasma Hcy levels were examined in 450 HD patients not administered vitamin B12 or folate. To examine the effect of vitamin B12 on plasma Hcy concentrations, we compared plasma Hcy concentrations in HD patients with and without vitamin B12 supplementation. To examine whether functional vitamin B12 deficiency exists even in HD patients with normal vitamin B12 concentrations, 15 HD patients (serum vitamin B12 concentrations, 250 to 2,100 pg/mL) were treated with vitamin B12 (mecobalamin, 1.5 mg/d) for 8 weeks. Serum concentrations of methylmalonic acid (MMA) and vitamin B12 were measured. Hcy levels were higher and folate levels were lower in patients with the TT and CT genotypes compared with patients with the CC genotype. Analysis of covariance to determine independent predictors of high Hcy levels identified low serum vitamin B12 and folate levels and high albumin (Alb) levels in CC-genotype patients, low folate levels and high Alb levels in CT-genotype patients, and low folate levels in TT-genotype patients. Plasma Hcy levels were lower in CC- and CT-genotype patients with vitamin B12 supplementation than in those without supplementation. Vitamin B12 supplementation for 8 weeks significantly reduced MMA concentrations in HD patients with normal serum vitamin B12 concentrations. These results indicate that MTHFR genotype influences the correlation of Hcy level with vitamin B12 and folate levels in HD patients. Functional vitamin B12 deficiency may exist, even in HD patients with normal vitamin B12 concentrations. The efficacy of vitamin B12 and folate supplementation on plasma Hcy levels may depend on MTHFR genotype.

Cross-Sectional Studies↗

PubMed2002

The M235T variant of the angiotensinogen gene and the body mass index are useful markers for prevention of hypertension in pregnancy: a tree-based analysis of gene-environment interaction.

We sought to perform a tree-based analysis of lifestyle risk factors for hypertension in pregnancy (HP) with univariate and multivariate analyses. Seventy-eight HP patients and 199 normal controls were recruited from primiparous women 20 to 34 years of age. Data from angiotensinogen (AGT) genotyping and data from a self-administered questionnaire about lifestyle were subjected to univariate and multivariate analyses. By dividing the subjects into two subgroups--those who possessed "the TT genotype of AGT" and "body mass index (BMI) < 24" and those who did not--we were able to examine the acquired risk factors for HP during pregnancy in these two groups. Multivariate analysis selected "mentally stressful condition" and "no antenatal training during pregnancy" in the former group, and "poorly balanced diet" in the latter group. Determination of factors obvious before pregnancy, such as genotype or prepregnancy BMI, may be useful for devising effective individualized strategies for preventing HP.

Adult↗

PubMed2002

An association between maternal smoking and preeclampsia in Japanese women.

In order to determine whether maternal smoking before or during pregnancy, or both, is associated with a reduced risk for preeclampsia in Japanese subjects, we conducted a case-control study that took other risk factors for preeclampsia into consideration. Seventy-one preeclampsia patients were matched with 142 controls for parity and age. Information from a self-administered questionnaire and clinical data such as maternal age, parity, family history of hypertension, prepregnancy body mass index (BMI), and pregnancy outcomes were analyzed. No significant difference was found between the groups in smoking rates before and during pregnancy (38.0 and 18.3% in preeclampsia patients and 38.0 and 16.9% in controls, respectively). However, classification of the subjects according to the presence of "prepregnancy high body mass (BMI > or = 24)" revealed a significant association between maternal smoking before pregnancy and preeclampsia in women with a prepregnancy high body mass (a smoking rate of 47.6% in patients with preeclampsia and 7.1% in controls, p < 0.05). This result suggests that there is a clear racial difference in the manifestation of preeclampsia with respect to the effect of smoking and that early intervention, particularly before pregnancy, to get obese women to stop smoking may be effective for preventing preeclampsia.

Adult↗

PubMed2002

[Human genome and made-to-order health care system].

Common diseases of adulthood are caused by interplay between environmental and genetic factors. Essential hypertension, diabetes mellitus, and coronary heart disease are the representative diseases, being the major cause of disability in aged population. The molecular pathogenesis of the most common forms of the diseases is still poorly understood. However, thanks to the rapid progress of "Human Genome Project", susceptibility genes of common diseases are expected to be isolated in the near future. At present, the word, "made-to-order medicine", means personalized medication in terms of doses or drug groups determined by genotypes of drug metabolizing genes. However, if knowledge about susceptibility genes and specific mutations for common diseases is available, made-to-order health care would be feasible. Before attainment of made-to-order health care system, we have to reach social agreement in usage of genetic informations. Genetic information can be used to prevent the onset of diseases, to assure early detection and treatment. This information can be used by probands and their relatives, but also by third parties such as insurers and employers. There are concerns that this information could lead to discrimination and social exclusion.

Delivery of Health Care↗