Association between maternal active smoking during pregnancy and placental weight: The Japan environment and Children's study.

INTRODUCTION: Maternal smoking during pregnancy is a well-known risk factor for reduced birthweight. However, research investigating the association between maternal smoking and placental weight is scarce and inconsistent. Our study was conducted to evaluate the association between maternal smoking and placental weight and placental weight/birthweight ratio (PW/BW ratio). METHODS: We used data from a birth cohort study, the Japan Environment and Children's Study (JECS). Main outcome measures were placental weight, PW/BW ratio, and the risk of high PW/BW ratio. High PW/BW ratio was defined as PW/BW ratio above the 90th percentile for gestational age and sex of offspring. The association between maternal smoking and placental weight was estimated as crude and as adjusted beta coefficients by applying linear regression analyses. Logistic regression analyses were also performed to estimate the association between maternal smoking and the risk of high PW/BW ratio. RESULTS: Of the 91,951 pregnant women, the mean placental weight and the mean PW/BW ratio were lowest for the group of women who had never smoked. Smokers had higher odds ratio for high PW/BW ratio compared with non-smokers. Furthermore, among smokers, the mean placental weight and mean PW/BW ratio were lowest in women who smoked less than 5 daily cigarettes, and highest in women who smoked 20 or more daily cigarettes during pregnancy. DISCUSSION: Placental weight was greater and PW/BW ratio was higher among smokers compared with non-smokers. Moreover, the number of daily cigarettes was positively associated with heavy placental weight.

Ankle-brachial pressure index and mini nutritional assessment in community-dwelling elderly people.

BACKGROUND: A low ankle-brachial pressure index (an ABPI value <0.90) is considered predictive of cardiovascular disease, and is widely thought to increase morbidity and mortality in the elderly. However, good nutrition is beneficial both for the health and the ability to resist and recover from the disease. OBJECTIVE: The aim of the present study was to evaluate the relationship between the ankle-brachial pressure index and the nutritional status of the elderly in a city of Kochi prefecture, Japan. METHODS: This was a cross-sectional study in which a total of 100 elderly people, both males and females, were screened for ankle-brachial pressure index (ABPI), nutritional status (through the use of the short form of the mini nutritional assessment), activities of daily living, lifestyle, gait speed (10MWT), postural stability (OLST), and functional mobility (TUG). RESULTS: About 67% of the participants were found to have a normal nutritional status, 27% were at risk of malnutrition, and six percent were classified as malnourished. The mean ABPI of the participants was 1.08±0.10, and three participants had an ABPI lower than 0.90. The ABPI was statistically higher in well nourished participants compared with those at risk of malnutrition or the malnourished. The mean ABPI was significantly higher in non-smokers compared with former smokers. The ABPI was found to correlate negatively with gait speed and with TUG score. CONCLUSION: Well-nourished elderly had a higher normal ankle-brachial pressure index as compared with the malnourished elderly. This study provides supportive evidence for the necessity of adequate nutrition for elderly people.

Histone chaperones: 30 years from isolation to elucidation of the mechanisms of nucleosome assembly and disassembly.

Some three decades have passed since the discovery of nucleosomes in 1974 and the first isolation of a histone chaperone in 1978. While various types of histone chaperones have been isolated and functionally analyzed, the elementary processes of nucleosome assembly and disassembly have been less well characterized. Recently, the tertiary structure of a hetero-trimeric complex composed of the histone chaperone CIA/ASF1 and the histone H3-H4 dimer was determined, and this complex was proposed to be an intermediate in nucleosome assembly and disassembly reactions. In addition, CIA alone was biochemically shown to dissociate the histone (H3-H4)2 tetramer into two histone H3-H4 dimers. This activity suggested that CIA regulates the semi-conservative replication of nucleosomes. Here, we provide an overview of prominent histone chaperones with the goal of elucidating the mechanisms that preserve and modify epigenetic information. We also discuss the reactions involved in nucleosome assembly and disassembly.