Seasonal and annual changes in the microbial communities of Ofunato Bay, Japan, based on metagenomics.

Five years of datasets from 2015 to 2019 of whole genome shotgun sequencing for cells trapped on 0.2-µm filters of seawater collected monthly from Ofunato Bay, an enclosed bay in Japan, were analysed, which included the 2015 data that we had reported previously. Nucleotide sequences were determined for extracted DNA from three locations for both the upper (1 m) and deeper (8 or 10 m) depths. The biotic communities analysed at the domain level comprised bacteria, eukaryotes, archaea and viruses. The relative abundance of bacteria was over 60% in most months for the five years. The relative abundance of the SAR86 cluster was highest in the bacterial group, followed by Candidatus Pelagibacter and Planktomarina. The relative abundance of Ca. Pelagibacter showed no relationship with environmental factors, and those of SAR86 and Planktomarina showed positive correlations with salinity and dissolved oxygen, respectively. The bacterial community diversity showed seasonal changes, with high diversity around September and low diversity around January for all five years. Nonmetric multidimensional scaling analysis also revealed that the bacterial communities in the bay were grouped in a season-dependent manner and linked with environmental variables such as seawater temperature, salinity and dissolved oxygen.

Relationship between two job stress models and coronary risk factors among Japanese part-time female employees of a retail company.

The objective of this study was to explore the associations between two major job stress models (job strain and effort-reward imbalance) and coronary heart disease (CHD) risk factors (blood pressure; total, high- (HDL) and low-density lipoprotein (LDL) cholesterol; and triglycerides) in Japanese part-time female employees of a retail company. The study population was either 35 yr old or between 40 and 63 yr old. Data collection was carried out in 2002; a total of 1,401 subjects participated in a medical examination and completed a questionnaire. After adjusting for other covariates (age, relative weight, tobacco use, alcohol consumption, lack of exercise, education, marital status, history of child bearing, medical treatment for disease, and occupation), a significant association was found between the effort-reward imbalance, a "high-cost and low-gain" condition at work, and a high prevalence of low HDL cholesterol (Odds ratio=4.4). A weak but unexpected association was found between job strain and low prevalence of low HDL cholesterol. In explanatory analysis with individual components of the two models, associations were evident between high extrinsic effort and high prevalence of low HDL cholesterol and low prevalence of high triglyceride, high job control and low prevalence of high systolic blood pressure, and high job demands and low prevalence of high systolic and diastolic blood pressure. In this cross-sectional study of Japanese part-time working women, a significant association was found between effort-reward imbalance and unfavorable HDL cholesterol profiles. The findings did not support the hypothesis that job strain is associated with CHD risk factors.