Level of serum undercarboxylated osteocalcin correlates with bone quality assessed by calcaneal quantitative ultrasound sonometry in young Japanese females.

The diagnostic criteria of osteoporosis were established based on bone mineral density (BMD). Therefore, BMD measured by dual energy X-ray absorptiometry has been recognized as the gold standard to diagnose osteoporosis. However, discrepancies between fracture risk and BMD have been recognized. Bone is composed of collagen scaffold reinforced by hydroxyapatite. Both protein scaffold and hydroxyapatite are involved in bone quality. BMD may indicate bone mineralization but potentially fail to assess the protein scaffold. Vitamin K contributes to bone mineralization and as a protein scaffold. A deficiency of vitamin K upregulates the level of serum undercarboxylated osteocalcin (ucOC), and serum ucOC correlates with fracture risk. However, direct association of ucOC and bone quality has not been demonstrated. For the present study, a total of 49 healthy young Japanese female college students underwent calcaneal; quantitative ultrasound sonometry (QUS) and determination of serological bone metabolic markers. QUS parameters were significantly correlated with serum 25-hydroxyvitamin D (25-OH-D) concentrations (P<0.05). A significant negative correlation was also identified between log transformed serum ucOC concentrations [Ln(ucOC)] and a QUS parameter, speed of sound (SOS) (P<0.05). Stepwise multiple regression analysis indicated that Ln(ucOC) was an independent determinant of SOS, and 25-OH-D was an independent determinant of the other two QUS parameters, transmission index (TI) and synthetic parameter osteo-sono-assessment index. As vitamin D is involved in bone mineralization, TI may reflect the mineralization. Correlation of vitamin K status, indicated by ucOC, with SOS may clarify the correlation between vitamin K status and bone quality, although the material factors that connect them have not been identified.

Physical inactivity associated with the risk of non-communicable diseases in Japanese working mothers with young children: A cross-sectional study in Nagano city, Japan.

Physical activity helps to prevent the development of chronic non-communicable diseases. However, childbearing generally reduces parents' level of physical activity, particularly in mothers. Therefore, mothers with young children generally have lower levels of physical activity and have a higher risk of developing non-communicable diseases. The aim of the present study was to examine this risk in Japanese working mothers with young children. A cross-sectional study was conducted in four nursery schools in Nagano city, Japan. All mothers were asked to complete a questionnaire regarding abnormal findings at their proximate annual medical examination, and were asked to record their normal physical activity. A total of 182 mothers completed the questionnaires, and 36 reported having abnormal findings (ABN group). Mothers in the ABN group were significantly older than those without abnormal findings (NOR; P=0.043). No significant differences in physical activity were observed between the two groups; however, mothers in the ABN group spent a significantly longer time sitting than those in the NOR group (P=0.028). Regarding socioeconomic characteristics, mothers in the ABN group had a significantly higher educational background (P=0.040) and a higher annual family income (P<0.001) compared with those in the NOR group, and significantly more mothers held full-time jobs (55.9 vs. 36.0%; P=0.005). Full-time working mothers typically had a significantly higher family income (P<0.001) and spent a significantly longer time sitting (P<0.001) compared with mothers in part-time and other work. Therefore, the results of the present study suggest that sedentary lifestyles, namely the amount of time spent sitting, may increase the risk of Japanese working mothers with young children developing non-communicable diseases.

Acute Multiple Cerebral Infarction in a Patient with an Accessory Mitral Valve.

A 96-year-old woman developed hemiparesis 2 weeks after orthopedic surgery. Magnetic resonance imaging revealed multiple cerebral infarctions in the bilateral hemisphere. Transthoracic echocardiography revealed a mobile structure attached to the anterior mitral leaflet that protruded toward the left ventricular outflow tract. The structure was identified as an accessory mitral valve. Doppler echocardiography showed that there was no significant left ventricular outflow obstruction. This is a rare case of a silent accessory mitral valve that was detected after multiple cerebral infarctions.

Seasonal variations in vitamin D status in indoor and outdoor female athletes.

Vitamin D (VD) insufficiency is a concern, particularly among young females. The VD status shows seasonal variations, since it correlates with duration of sunlight exposure. VD insufficiency in indoor athletes is therefore suggested in winter. The aim of the present study was to determine seasonal variations in VD and bone status among indoor and outdoor female athletes. The prospective study was conducted in participants aged 20-22 years old. The participants comprised of 15 indoor and 15 outdoor athletes. The biochemical markers and bone parameters were measured in March, June, September and December. The serum 25-hydroxyvitamin D (25-OH-VD) concentration showed a seasonal oscillation, with a nadir in March (indoor, 19±4.0 ng/ml; outdoor, 32±2.7 ng/ml) and a peak in September (indoor, 32±6.6 ng/ml; outdoor, 39±5.7 ng/ml). The amplitude of oscillation was greater in the indoor compared to the outdoor athletes. Seasonal variations in serum calcium exhibited a similar pattern, while the parathyroid hormone showed an inverse pattern to serum 25-OH-VD. The nadir in bone mass, measured as speed of sound, occurred in June after peaking in December among the indoor and outdoor athletes. The pattern followed 3 months after the changes in 25-OH-VD. Indoor sports athletes are more susceptible to VD insufficiency compared to outdoor sports athletes. Insufficiency is most likely to arise in winter, and could affect bone mineralization observed 3 months after.

Milk fortified with vitamin D could reduce the prevalence of vitamin D deficiency among Japanese female college students.

SUMMARY: The mean serum 25-OH-D was 23.1 ng/mL in 49 female Japanese college students, and concentrations in 33% of them were ≤20 ng/mL. Subsequently, they consumed milk fortified with 2 µg of vitamin D daily for 8 weeks. Then, 25-OH-D increased to 36.0 ng/mL and all values were ≥20 ng/mL. PURPOSE: Commercial milk in the USA is fortified with vitamin D (VD), whereas food fortified with VD is unpopular in Japan even though dietary sources of this vitamin are limited. Therefore, young Japanese females might be VD deficient. This study assesses the effects of ingesting milk fortified with VD among Japanese female college students. METHODS: Forty-nine female college students consumed 180 mL of milk fortified with 2 µg of VD daily for 8 weeks. This amount of VD in the milk was similar to that in commercial milk sold in the USA. Serum concentrations of 25-OH-D were measured in venous blood collected before and after the ingestion period. RESULTS: The initial serum 25-OH-D concentration was 23.1 ng/mL and concentrations in 33% of the participants were ≤20 ng/mL. After 8 weeks, serum 25-OH-D increased to 36.0 ng/mL and all values were ≥20 ng/mL. Serum Ca and FGF-23 also increased and PTH, NTX, and BAP significantly decreased. CONCLUSIONS: The high prevalence of VD deficiency in Japanese female college students was decreased by consuming VD-fortified milk.