Wheelchair propulsion biomechanics and wheelers' quality of life: an exploratory review.

PURPOSE. To provide an overview of associations between wheelchair propulsion biomechanics for both everyday and racing wheelchairs, wheeling-related upper limb injuries, and quality of life of manual wheelchair users through a synthesis of the available information. METHODS. A search of publications was carried out in PubMed and SportsDiscus databases. Studies on wheelchair propulsion biomechanics, upper limb injuries associated with wheelchair propulsion and quality of life of wheelchair users were identified. Relevant articles cited in identified articles but not cited in PubMed or SportsDiscus were also included. RESULTS. Wheelchair sports participation has positive impact on quality of life and research in racing wheelchair biomechanics can indirectly promote the visibility of wheelchair sports. The impact of pushrim-activated power-assisted wheelchairs (a hybrid between manual and battery-powered wheelchairs) and geared manual wheels on wheelers' everyday life were discussed. CONCLUSIONS. The study of wheelchair propulsion biomechanics focuses on how a wheelchair user imparts power to the wheels to achieve mobility and the accumulated knowledge can help to improve wheelchair users' mobility, reduce physical stress associated with wheelchair propulsion, and as a result, enhance quality of life.

A novel extract SB-300 from the stem bark latex of Croton lechleri inhibits CFTR-mediated chloride secretion in human colonic epithelial cells.

An oligomeric proanthocyanidin (SP-303) extracted from the bark latex of the tree Croton lechleri (family Euphorbiaceae) is a potent inhibitor of cholera toxin-induced fluid accumulation and chloride secretion. The manufacturing process for SP-303 was optimized and simplified to produce an increased yield of the herbal extract. The novel extract (named SB-300) contained on average 70.6+/-7.2% SP-303 by weight (mean +/- S.D.; n=56 lots). Here, we describe the effectiveness of SB-300 on cAMP-regulated chloride secretion, which is mediated by the cystic fibrosis transmembrane conductance regulator Cl- channel (CFTR) in human colonic T84 cells. Exposure of the apical surface to SB-300 blocked forskolin-stimulated Cl- secretion by 92.2+/-3.0% with a half-maximal inhibition constant (KB) of 4.8+/-0.8 microM. For SP-303, stimulated Cl- currents were decreased by 98.0+/-7.2 % and KB averaged 4.1+/-1.3 microM. There was no significant difference between the blocking kinetics of SP-303 and SB-300. Forskolin-stimulated whole cell Cl- currents were effectively blocked by extracellular addition of SB-300 (63+/-8.5%; n=3) and to a similar extent by SP-303 (83 +/- 0.6%; n=2; at 50 microM each). Both extracts inhibited a time- and voltage-independent Cl- conductance, which indicated the involvement of CFTR Cl- channels. We conclude that both SP-303 (used in Provir) and SB-300 (used in NSF Normal Stool Formula) are novel natural products that target the CFTR Cl- channel. SB-300 is a low cost herbal extract and may present a complementary and alternative medicine approach for the treatment of fluid loss in watery diarrhea.