A simple method for equine kinematic gait event detection.

BACKGROUND: Previous studies have validated methods for determining kinematic gait events using threshold-based techniques. However, a simple method that can be successfully applied to walk, trot and canter is yet to be identified. OBJECTIVES: To develop a simple kinematic method to identify the timing of hoof contact (hoof-on), peak vertical force and lift off (hoof-off), which can be applied in walk, trot and canter. STUDY DESIGN: In vivo method authentication study. METHODS: Horses (n = 3) were ridden in walk, trot and canter down a runway on which four force plates were arranged linearly. Three-dimensional forces were recorded at a sampling rate of 960 Hz and were synchronised with a 10-camera motion analysis system sampling at 120 Hz. Events identified from vertical ground reaction force (GRFz) data were hoof-on (GRFz>50N), peak vertical force (GRFzpeak ) and hoof-off (GRFz<50N). Kinematic identification of hoof-on and hoof-off events was based on sagittal planar angles of the fore- and hindlimbs. Peak metacarpophalangeal (MCP)/metatarsophalangeal (MTP) joint extension was used to assess the time of GRFzpeak . The accuracy (mean) and precision (s.d.) of time differences between kinetic and kinematic events were calculated for fore- and hindlimbs at each gait. RESULTS: Hoof-off was determined with better accuracy (range: -3.94 to 8.33 ms) and precision (range: 5.43-11.39 ms) than hoof-on across all gaits. Peak MCP angle (range: 5.83-19.65 ms) was a more precise representation of GRFzpeak than peak MTP angle (range: 11.49-67.75 ms). MAIN LIMITATIONS: The sample size was small and therefore further validation is required. The proposed method was tested on a single surface. CONCLUSIONS: This study proposes a simple kinematic method of detecting hoof-on, hoof-off and GRFzpeak at walk, trot and canter. Further work should focus on validating the methodology in a larger number of horses and should extend the method for use on surfaces with varying levels of compliance.

Prioritization of active antimalarials using structural interaction profile of Plasmodium falciparum enoyl-acyl carrier protein reductase (PfENR)-triclosan derivatives.

An empirical relationship between the experimental inhibitory activities of triclosan derivatives and its computationally predicted Plasmodium falciparum enoyl-acyl carrier protein (ACP) reductase (PfENR) dock poses was developed to model activities of known antimalarials. A statistical model was developed using 57 triclosan derivatives with significant measures (r = 0.849, q(2) = 0.619, s = 0.481) and applied on structurally related and structurally diverse external datasets. A substructure-based search on ChEMBL malaria dataset (280 compounds) yielded only two molecules with significant docking energy, whereas eight active antimalarials (EC(50) < 100 nM, tested on 3D7 strain) with better predicted activities (pIC(50) ~ 7) from Open Access Malaria Box (400 compounds) were prioritized. Further, calculations on the structurally diverse rhodanine molecules (known PfENR inhibitors) distinguished actives (experimental IC(50) = 0.035 µM; predicted pIC(50) = 6.568) and inactives (experimental IC(50) = 50 µM; predicted pIC50 = -4.078), which showed that antimalarials possessing dock poses similar to experimental interaction profiles can be used as leads to test experimentally on enzyme assays.

Ameliorative effect of curcumin on hepatotoxicity induced by chloroquine phosphate.

India is one of the most endemic areas, where malaria predominates and its control has become a formidable task. Chloroquine phosphate (CQ) on account of its rapid action on blood schizontocide of all the malarial parasite strains has become the most widely prescribed drug for prophylaxis and treatment of malaria. Toxicity of CQ is most commonly encountered at therapeutic and higher doses of treatment. Thus, the present study was undertaken to evaluate the protective effect of Curcumin, a herbal antioxidant obtained from Curcuma longa, on hepatic biochemical and histopathological status of CQ induced male mice. Swiss albino male mice were administered oral doses of CQ (100mg/kg body wt., 200mg/kg body wt. and 300mg/kg body wt.) and CQ+curcumin (300mg/kg body wt.+80mg/kg body wt.) for 45 days. A withdrawal of high dose treatment for 45 days was also studied. Administration of CQ brought about a significant decrease in Protein content with a decline in SDH, ATPase and ALKase activities, whereas ACPase activity was found to be significantly increased following CQ treatment. Antioxidant enzyme SOD registered a significant reduction as opposed to TBARS which was found to be elevated in a significant manner in the CQ treated groups as compared to control. Gravimetric indices (body weight and organ weight) declined significantly following CQ treatment. Administration of curcumin exhibited significant reversal of CQ induced toxicity in hepatic tissue. Protein content, SDH, ATPase, ALKase, ACPase, SOD, TBARS, body weight and organ weight were found to be comparable to that of control group after curcumin administration. Thus, obtained results led us to conclude the curative potential of curcumin against CQ induced hepatotoxicity.

Social interaction in hearing and deaf preschoolers: successes and failures in initiations.

Dyadic free play of 32 children (16 deaf, 16 hearing) who attended the same preschool was videotaped on 2 occasions, once with a hearing partner and once with a deaf partner. Each 15-min play session was analyzed in terms of the hearing and deaf children's initiation strategies, their responsiveness to one another's initiations, and the characteristics of successful and unsuccessful initiations. Results indicated that mean interaction duration and proportion of time spent in interaction were greater in "like" (hearing child and hearing partner or deaf child and deaf partner) as opposed to "mixed" dyads. Contrary to previous hypotheses about inadequate communication skills, deaf children were found to be persistent initiators who frequently combined social acts. Underlying similarities were also apparent in the types of initiating acts used by hearing and deaf children. At the same time, however, the deaf preschoolers encountered interaction difficulties. Their initiation attempts were more likely than those of their hearing counterparts to be actively refused. They were also more likely to be recipients of inappropriate initiations, such as gestures or vocalizations to their backs. These results were discussed in terms of previous hypotheses about inferior social skills of the deaf and for their relevance to programs interested in integrating hearing and nonhearing children.