Divers' heart rates were measured under real ocean diving conditions with the purpose of evaluating the workload during SCUBA diving. For the subjects, all-out tests were conducted and evaluated in each of the following conditions: 1. ergometer cycling, 2. ergometer cycling using diving regulator, 3. fin-swimming in a swimming pool with diving equipment. No significant heart rate difference was found between the pre-dive and post dive of each subject; although, in novice divers, high heart rates such as 140/min or more were observed especially during the dive gear wearing phase on the topside and/or floating on the surface phase, suggesting there should be some high heart rate inducing factors, other than the exercise, like stress. Whereas, in the results of the all-out tests, the heart rate for fin-swimming was 16~18 beats/min lower, as well as 5.7~14.2 ml/kg/min lower for VO₂max, as compared to the ergometer cycling. This may suggest that fin-swimming like scuba diving could give a diver some degree of physical load without on increased heart rate.

Osteoporosis is a bone pathology leading to increased fracture risk and challenging the quality of life. The aim of this study was to evaluate the effect of an anthraquinone glycoside, aloin, on osteogenic induction of MC3T3-E1 cells. Aloin increased alkaline phosphatase (ALP) activity, an early differentiation marker of osteoblasts. Aloin also increased the ALP activity in adult human adipose-derived stem cells (hADSC), indicating that the action of aloin was not cell-type specific. Alizarin red S staining revealed a significant amount of calcium deposition in cells treated with aloin. Aloin enhanced the expression of osteoblast differentiation genes, Bmp-2, Runx2 and collagen 1a, in a dose-dependent manner. Western blot analysis revealed that noggin and inhibitors of p38 MAPK and SAPK/JNK signals attenuated aloin-promoted expressions of Bmp-2 and Runx2 proteins. siRNA mediated blocking of Wnt-5a signaling pathway also annulled the influence of aloin, indicating Wnt-5a dependent activity. Inhibition of the different signal pathways abrogated the influence of aloin on ALP activity, confirming that aloin induced MC3T3-E1 cells into osteoblasts through MAPK mediated Wnt and Bmp signaling pathway.
Adult ; Alkaline Phosphatase ; Blotting, Western ; Calcium ; Collagen ; Core Binding Factor Alpha 1 Subunit ; Humans ; Osteoblasts ; Osteoporosis ; p38 Mitogen-Activated Protein Kinases ; Pathology ; Quality of Life ; RNA, Small Interfering ; Signal Transduction ; Stem Cells

BACKGROUND: More than 140 million people drink arsenic-contaminated groundwater. It is unknown how much arsenic exposure is necessary to cause neurological impairment. Here, we evaluate the relationship between neurological impairments and the arsenic concentration in drinking water (ACDW). PARTICIPANTS AND METHODS: A cross-sectional study design was employed. We performed medical examinations of 1867 residents in seven villages in the Thabaung township in Myanmar. Medical examinations consisted of interviews regarding subjective neurological symptoms and objective neurological examinations of sensory disturbances. For subjective neurological symptoms, we ascertained the presence or absence of defects in smell, vision, taste, and hearing; the feeling of weakness; and chronic numbness or pain. For objective sensory disturbances, we examined defects in pain sensation, vibration sensation, and two-point discrimination. We analyzed the relationship between the subjective symptoms, objective sensory disturbances, and ACDW. RESULTS: Residents with ACDW ≥ 10 parts per billion (ppb) had experienced a "feeling of weakness" and "chronic numbness or pain" significantly more often than those with ACDW < 10 ppb. Residents with ACDW ≥ 50 ppb had three types of sensory disturbances significantly more often than those with ACDW < 50 ppb. In children, there was no significant association between symptoms or signs and ACDW. CONCLUSION Subjective symptoms, probably due to peripheral neuropathy, occurred at very low ACDW (around 10 ppb). Objective peripheral nerve disturbances of both small and large fibers occurred at low ACDW (> 50 ppb). These data suggest a threshold for the occurrence of peripheral neuropathy due to arsenic exposure, and indicate that the arsenic concentration in drinking water should be less than 10 ppb to ensure human health.
Adolescent ; Adult ; Arsenic ; analysis ; toxicity ; Cross-Sectional Studies ; Dietary Exposure ; adverse effects ; Dose-Response Relationship, Drug ; Drinking Water ; adverse effects ; chemistry ; Female ; Groundwater ; chemistry ; Humans ; Male ; Middle Aged ; Myanmar ; epidemiology ; Peripheral Nervous System Diseases ; chemically induced ; epidemiology ; physiopathology ; Sensation Disorders ; chemically induced ; epidemiology ; physiopathology ; Water Pollutants, Chemical ; analysis ; toxicity ; Young Adult