Effects of weight bearing and non-weight bearing exercises on bone properties using calcaneal quantitative ultrasound.

OBJECTIVE: This study was designed to investigate bone properties using heel quantitative ultrasound (QUS) in young adults participating in various sports. METHODS: A cross sectional study was performed on Chinese male students (n = 55), aged 18-22 years. Subjects with previous fractures or suffering from any diseases known to affect bone metabolism or taking any medication with such an effect, were not included. The subjects were categorised according to their main sporting activities, including soccer (n = 15) (a high impact, weight bearing exercise), dancing (n = 10) (a low impact, weight bearing exercise), and swimming (n = 15) (non-weight bearing exercise). A sedentary group acted as controls (n = 15). A reproducibility study of the velocity of sound (VOS) and the broadband ultrasound attenuation (BUA) measurement was performed and analysed using the intraclass correlation coefficient (ICC). RESULTS: There was good intra-investigator and inter-investigator agreement (ICC > or = 0.8; p < 0.05) in the measurement of BUA and VOS. No significant differences in BUA and VOS (p > 0.05) were found between the dominant and non-dominant heel. Soccer players (137 +/- 4.3 dB/MHz; 1575 +/- 56 m/s; 544.1 +/- 48.4) and dancers (134.6 +/- 3.7 dB/MHz; 1538 +/- 46 m/s; 503.0 +/- 37.0) had significantly higher BUA, VOS, and stiffness index (SI) scores (p < 0.05), respectively, than swimmers (124.1 +/- 5.1 dB/MHz; 1495 +/- 42 m/s; 423.3 +/- 46.9) and the sedentary control group (119.9 +/- 6.1 dB/MHz; 1452 +/- 41 m/s; 369.9 +/- 46.4). A trend of a significant linear increase with the weight bearing and high impact exercise was revealed in all QUS parameters (p < 0.05). CONCLUSION: This cross sectional study indicated that regular participation in weight bearing exercise in young people might be beneficial for accruing peak bone mass and optimising bone structure.

Telemedicine: a pilot study in nursing home residents.

BACKGROUND: Telemedicine has been applied successfully in various fields of medicine. This mode of health care delivery may potentially be useful in supporting frail nursing home residents who require multidisciplinary geriatric services. OBJECTIVE: To assess the feasibility of telemedicine in providing geriatric services to nursing home residents, and whether this mode of care resulted in increased productivity and savings. METHODS: A local 200-bed nursing home supported by the Community Geriatric Assessment Team (CGAT) was recruited. Over a 1-year period, teleconferencing was used to replace conventional geriatric outreach services. The feasibility of telemedicine was evaluated by participating specialists. Productivity gains, consumption of hospital services and user satisfaction were measured. RESULTS: Telemedicine was adequate for service delivery in up to 99% of cases, depending on the specialty. A greater number of clients were served and follow-up intervals were shortened. The service was cheaper than conventional outreach or clinic activities, and acceptable to users and clients. In particular, savings were made through a 9% reduction in visits to the Accidents and Emergency Department and in 11% fewer admissions to acute hospital wards. CONCLUSION: telemedicine is a feasible means of delivering multidisciplinary care to frail nursing home residents, and may result in increased productivity and significant savings.

Proteolytic activation of grass carp (Ctenopharygodon idellus) liver alcohol dehydrogenase.

Two different forms of alcohol dehydrogenase (ADH) were prepared from the liver of grass carp, using ion-exchange chromatography on DEAE-cellulose and affinity chromatography on Affi-gel Blue agarose. In the presence of dithiothreitol and benzamidine. ADH-l, a dimeric protein with native molecular weight of 80 kDa, was obtained. However, in their absence, another form of the enzyme, ADH-C, consisting of two 27 kDa and two 13 kDa subunits tightly but non-covalently associated with each other, can be isolated. ADH-C represented a cleaved form of the enzyme and was shown to be derived from the original, intact form, ADH-l through limited and specific proteolytic cleavage. Surprisingly, such a cleavage caused an activation of the enzyme toward the oxidation of ethanol at pH 10.5. The Vmax value of ADH-C was 5.16-fold greater than that of ADH-l. However, ADH-C had much weaker binding affinity for the alcohol. Its Km value toward ethanol was 163-fold higher than that of ADH-l.

Novel organization of microtubules in cultured central nervous system neurons: formation of hairpin loops at ends of maturing neurites.

Using the high voltage electron microscope, we have examined cultured embryonic neurons in order to understand better the organization of microtubules in developing neurites. We found that, in embryonic chick retina neurons, microtubules were abundant in the ends of neurites and showed an unusual pattern of organization. Most striking was the presence of microtubule loops; after entering the flattened region of a growth cone, microtubules frequently made tight 180 degrees turns. Occasionally these looping microtubules re-entered the neurite and returned in the direction of the cell body. Positive identification of the loop structures as microtubules was made by specific immunocytochemical labeling. Quantitative analysis showed that more than half of the retina neurons that were dissociated on embryonic day 8 and kept in culture for 4 to 6 days (E8C4 and E8C6) contained at least one microtubule that made a 180 degrees turn at flat regions along or at the tips of neurites. The area within the loops typically contained larger membranous organelles, whereas only small vesicles were seen outside the loops. Fine filaments were seen to interconnect the loops at various places, suggesting the possibility that they played a role in maintaining the shape of microtubule loops. Examination of other neurons showed that tight microtubule loops were prominent in chick spinal cord neurons, but they were rarely seen in neurons of the sympathetic ganglia or dorsal root ganglia or in NG108-15 cloned cells. Developmentally, no loops were observed in E8C1 retina neurons, but retina neurons dissociated from older embryos (12 days) did show loops after 1 day in culture; these data suggest that microtubule loops may be abundant around embryonic day 12 to 13 in the chick retina. The possible significance of this unusual microtubule organization to the control of neurite growth and bidirectional transport is discussed.