Environmental and physical factors predisposing middle-aged and older Japanese adults to falls and fall-related fractures in the home.

AIM: To identify environmental and physical factors that predispose middle-aged and older Japanese adults to falls and fall-related fractures in the home. METHODS: A cross-sectional survey was carried out in 2014. Self-administered questionnaires were distributed to 15 000 community-dwelling adults in Japan. The overall crude response rate was 13%. Response data were analyzed from 1561 individuals aged ≥40 years using multiple imputation to analyze missing data. We evaluated falls without fractures and fall-related fractures during the previous 3 years according to demographic, physical and environmental factors, including age, sex, long-term care insurance certification, type of house and barrier-free housing. RESULTS: Of the 1561 adults (mean age 68.1 ± 13.0 years), 28% experienced a fall in the home. Among the individuals who experienced a fall, 11% experienced fall-related fractures. These individuals were more likely to be women (OR 2.4, 95.0% CI 1.1-5.1), have LTCI certification (OR 3.9, 95.0% CI 1.6-9.4) and be living in a barrier home (OR 4.0, 95.0% CI 1.6-9.8), after adjustment for covariates. CONCLUSIONS: Environmental factors, such as living in a barrier home, are critical for fall-related fractures, in addition to demographic and physical factors. A multidisciplinary approach that considers both physical and environmental factors is necessary for reducing the incidence of fall-related fractures among middle-aged and older Japanese adults. Geriatr Gerontol Int 2018; 18: 1372-1377.

Neurula rotation determines left-right asymmetry in ascidian tadpole larvae.

Tadpole larvae of the ascidian Halocynthia roretzi show morphological left-right asymmetry. The tail invariably bends towards the left side within the vitelline membrane. The structure of the larval brain is remarkably asymmetric. nodal, a conserved gene that shows left-sided expression, is also expressed on the left side in H. roretzi but in the epidermis unlike in vertebrates. We show that nodal signaling at the late neurula stage is required for stereotypic morphological left-right asymmetry at later stages. We uncover a novel mechanism to break embryonic symmetry, in which rotation of whole embryos provides the initial cue for left-sided expression of nodal. Two hours prior to the onset of nodal expression, the neurula embryo rotates along the anterior-posterior axis in a counterclockwise direction when seen in posterior view, and then this rotation stops when the left side of the embryo is oriented downwards. It is likely that epidermis monocilia, which appear at the neurula rotation stage, generate the driving force for the rotation. When the embryo lies on the left side, protrusion of the neural fold physically prevents it from rotating further. Experiments in which neurula rotation is perturbed by various means, including centrifugation and sandwiching between glass, indicate that contact of the left epidermis with the vitelline membrane as a consequence of neurula rotation promotes nodal expression in the left epidermis. We suggest that chemical, and not mechanical, signals from the vitelline membrane promote nodal expression. Neurula rotation is also conserved in other ascidian species.

A Monoclonal Antibody Specific to Embryonic Trunk-Lateral Cells of the Ascidian Halocynthia roretzi Stains Coelomic Cells of Juvenile and Adult Basophilic Blood Cells: (ascidians/embryonic trunk-lateral cells/specific monoclonal antibody/juvenile coelomic cells/adult blood cells).

In spite of extensive knowledge on the structure and function of ascidian blood cells, little is known about their embryological origin. In the present investigation, the developmental fate of trunk lateral cells (TLCs) was explored using a specific monoclonal antibody. TLCs comprise a group of undefined embryonic cells of the ascidian Halocynthia roretzi, which arise from the A7.6 blastomeres of a 64-cell embryo. The antigenicity first appeared at the middle tailbud stage in a pair of TLC-clusters situated lateral to the brain stem of the bilaterally symmetrical embryo. The position and number of stained cells did not change during later embryogenesis until hatching. After hatching, the stained cells were found in the entire trunk region of the swimming larva. After metamorphosis, cells that expressed the antigen were present within the coelom and within the tunic layer of the juvenile. In addition, the antibody stained adult basophilic blood cells. These observations suggest a relationship of this group of embryonic cells with the prospective blood forming mesenchymal cells.