Primary afferent somatosensory neurons mediate our sense of touch in response to changes in ambient pressure. Molecules that detect and transduce thermal stimuli have been recently identified, but mechanisms underlying mechanosensation, particularly in vertebrate organisms, remain enigmatic. Traditionally, mechanically evoked responses in somatosensory neurons have been assessed one cell at a time by recording membrane currents in response to application of focal pressure, suction, or osmotic challenge. Here, we used radial stretch in combination with live-cell calcium imaging to gain a broad overview of mechanosensitive neuronal subpopulations. We found that different stretch intensities activate distinct subsets of sensory neurons as defined by size, molecular markers, or pharmacological attributes. In all subsets, stretchevoked responses required extracellular calcium, indicating that mechanical force triggers calcium influx. This approach extends the repertoire of stimulus paradigms that can be used to examine mechanotransduction in mammalian sensory neurons, facilitating future physiological and pharmacological studies.mechanotransduction ͉ sensory signaling ͉ somatosensation ͉ touch

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Context Follicle-stimulating hormone (FSH) may have independent actions on bone remodeling and body fat regulation. Cross-sectionally, we have shown that serum FSH is associated with bone mineral density (BMD) and body fat in older postmenopausal women, but it remains unknown whether FSH predicts bone and fat changes. Objective We examined whether baseline FSH level is associated with subsequent bone loss or body composition changes in older adults. Setting, Design, Participants We studied 162 women and 158 men (mean age 82 ±4 years) from the AGES-BMA cohort, a substudy of the AGES-Reykjavik Study of community-dwelling older adults. Skeletal health and body composition were characterized at baseline and 3 years later. Main Outcomes Annualized change in BMD and body composition by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT). Models were adjusted for serum estradiol and testosterone levels. Results There was no evidence for an association between baseline FSH level and change in BMD or body composition by DXA or QCT. For femoral neck areal BMD, adjusted mean difference (95% CI) per SD increase in FSH was 1.3 (-0.7, 3.3) mg/cm 2/year in women, and -0.2 (-2.6, 2.2) mg/cm 2/year in men. For visceral fat, adjusted mean difference (95% CI) per SD increase in FSH was 1.80 (-0.03, 3.62) cm 2/year in women, and -0.33 (-3.73, 3.06) cm 2/year in men. Conclusions Although cross-sectional studies and studies in perimenopausal women have demonstrated associations between FSH and BMD and body composition, in older adults, FSH level is not associated with bone mass or body composition changes.

The study examined the prevalence and degree of lactate elevation in diabetic ketoacidosis, and explored which biochemical abnormalities predicted L-lactate levels. Methods:We reviewed episodes of diabetic ketoacidosis from 79 diabetes patients (one episode per patient). Separate univariate linear regression models were specified to predict lactate level from each of nine biochemical variables.