Seasonal variation in fish school spatial distribution and abundance under the Kuroshio regular pattern and the large meander in Suzu coastal waters.

The Kuroshio Current can take two paths; usually it follows the regular pattern but occasionally it follows a pattern known as the large meander. In this study, we investigated the abundance of fish that migrate to coastal waters and the spatial distribution of fish schools under both Kuroshio patterns in Suzu district, Kochi prefecture, where the set net is the main fishery industry. We clarified the seasonal variation in the density and distribution of fish schools using a quantitative echo sounder. The effects of the Kuroshio large meander (LM) depended on the season. There was no effect of current pattern in summer or autumn, but in winter and spring the LM altered the marine environment and fish distributions. Cold water masses were formed in the survey area during winter and spring during the LM, and the water temperature dropped significantly compared with during the Kuroshio non-large meander (NLM). This altered the fish species and the distribution of fish schools in the survey area. The catches of Japanese horse mackerels (Trachurus japonicus) and Yellowtails (Seriola quinqueradiata) were much higher during the LM compared with those during the NLM. Unlike these two species, the small-sized pelagic fishes in spring has decreased significantly during the LM.

Effect of physical stimulation (gingival massage) on age-related changes in gingival microcirculation.

The decline in circulatory function with aging may be alleviated by a combination of gingival massage (physical stimulation) and mechanical cleaning. Several studies have reported the systemic effect of physical stimulation on various parts of the body, including its therapeutic effect on pain in the neck and shoulders that becomes evident with age, and improvement in blood circulation. In contrast, few studies have reported on the changes in gingival microcirculation induced by gingival massage, while no previous study has evaluated the effect of gingival microcirculation on age-related changes in the hemodynamics of the oral cavity. This study aimed to investigate how gingival massage affects age-related changes in gingival microcirculation. Male Wistar rats (7-week, 6-month and 1-year old) were prepared for a gingival massage group and a control group. Mechanical stimulation was applied on the maxillary molar gingiva for 5 seconds twice a week for 4 weeks. Subsequently, gingival reactive hyperemia was measured using a laser Doppler flowmeter. In addition, morphological analyses were also performed by hematoxylin and eosin and Indian ink staining and a vascular resin cast model. Base Flow, maximum response (Peak), and time required for the maximum response to halve (T1/2) were reduced in 1-year-old rats compared with the other age groups. In the mechanical stimulated group, T1/2 was increased in 7-week, 6-month, and 1-year-old rats, and total blood flow (Mass) was increased in 6-month and 1-year-old rats. In addition, clear blood vessel networks and loop-like revascularization were only observed in the mechanical stimulated group. Changes in age-related decline in gingival microcirculatory function and vascular construction were reported in this study, and the results suggested that gingival massage activates both the functional and morphological aspects of gingival microcirculation and may be effective for maintaining oral health.

Albuminuria, C-reactive protein, and socioeconomic factors are associated with periodontal status in subjects with type 2 diabetes.

Diabetes and periodontitis may increase risk of cardiovascular disease. Whether albuminuria, C-reactive protein (CRP), and socioeconomic factors, known as cardiovascular risks in subjects with poorly controlled diabetes, are independently associated with periodontal status in well-controlled diabetes remains to be elucidated. In 503 subjects with type 2 diabetes, the cross-sectional associations of clinical and socioeconomic factors with periodontal parameters were investigated. Periodontal parameters on all teeth included the probing pocket depth at 6 sites per tooth, bleeding on probing, the plaque score, tooth mobility, and the number of teeth. The subjects had a mean HbA1c value of 6.85% and a median CRP value of 0.06 mg/dL, and 27.9% of the subjects had albuminuria. Albuminuria and CRP values had significant associations with several periodontal parameters, whereas other variables including HbA1c did not. Subjects with albuminuria had significantly higher HbA1c, CRP, and % sites of pocket depth ≥ 4 mm than subjects with normoalbuminuria; additionally, those with high CRP (≥ median) had significantly higher body mass index, HbA1c, % sites of pocket depth ≥ 4 mm, and plaque score than those with low CRP. In multiple linear regression analysis, albuminuria, CRP, education, smoking, and dental attendance exhibited significant associations with periodontal parameters, independent of the effect of age, sex, body mass index, and diabetes therapy. Albuminuria, CRP, education, smoking, and dental attendance were independently associated with periodontal parameters even in subjects with a mean of HbA1c of 6.85%, implying the importance of these factors for the prevention of cardiovascular disease.