Intravenous tranexamic acid and lower limb arthroplasty-a randomised controlled feasibility study.

Tranexamic acid (TA) is widely reported to reduce bleeding and the risk of blood transfusion in patients undergoing lower limb arthroplasty. No study in this setting has had adequate power to examine for the effect of TA on either uncommon, but clinically important, adverse events or patient-centric endpoints. A large randomised controlled trial (RCT) is required to address these questions. As a preliminary feasibility study, we conducted an investigator-initiated, prospective, randomised, double blind placebo-controlled trial in 140 patients, aged 45 years or older, undergoing elective primary or revision hip or knee joint replacement. Subjects were randomised to receive intravenous (IV) TA or a placebo. The primary endpoints were the proportion of patients receiving allogenic blood transfusion and the feasibility of extending our trial methodology to a large trial of TA in this population. Secondary endpoints included a range of adverse clinical and surgical events as well as several patient-centric questionnaires. Red blood cell transfusion occurred in 15% of all patients prior to discharge from hospital. Transfusion rates were significantly different between the TA and placebo groups (8.5% versus 21.7%, P=0.03). Three out of four feasibility endpoints were met, with recruitment being slower than expected. No significant differences were seen between groups in the secondary endpoints. Despite a lower rate of transfusion than that widely reported, IV TA reduced transfusion in patients undergoing lower limb arthroplasty. Our trial methodology would be feasible in the setting of a large multicentre study to investigate whether TA is safe and reduces bleeding in lower limb arthroplasty.

The use of polymers coupled with metallised electrodes to allow H(2)O(2) detection in the presence of electrochemical interferences.

One of the most important parameters to be considered when developing a biosensor based on the use of oxidase enzymes is the selective determination of H(2)O(2) in the presence of easily oxidisable interferents. In this work one approach was taken to overcome this problem-the use of metallised carbon electrodes in conjunction with polymers. Polymers, both conducting and nonconducting, have recently become very interesting materials for the suppression of interferences. They are easy to grow on any electrode surface and the extensive range of polymers available provides a huge scope for the large variety of sensors that exist today. They can be grown in organic or aqueous media. In this work, three polymers (polypyrrole, polyaniline and 1,3-diaminobenzene) were examined for their interferent-preventing potential on several types of electrodes. Previous work carried out at the Laboratory of Sensor Development has shown the co-deposition of ruthenium and rhodium on carbon to provide an electrode surface which is highly catalytic and selective towards H(2)O(2)[1]. The co-deposition of Ru, Rh and Pt, as well as Pt on Ru-Rh electrodes was investigated and all these transducers were coupled with the use of the polymers for enhanced elimination of interferences with highly promising results obtained. The best system was seen to be a Ru-Rh metallised electrode polymerised with poly(1,3-diaminobenzene). At an applied potential of +100 mV the response to H(2)O(2) was approximately 200 times greater than the response of any of the potential interferences.

Dissemination of central nervous system tissue from the brain and spinal cord of cattle after captive bolt stunning and carcass splitting.

In the absence of reliable live animal tests for the presence of BSE in cattle, a number of measures have been applied to exclude specified risk materials (SRM) from the human food chain. However, concerns remain that current practices in the stunning and slaughter of cattle may disseminate central nervous system (CNS) tissue to meat and meat contact surfaces. The objective of this study was to establish the particular risks of CNS tissue dissemination associated with captive bolt stunning and carcass splitting. The study applied enzyme linked immunosorbent assays (ELISAs) in the detection and quantification of two CNS proteins, syntaxin 1b and GFAP. The study observed extensive dispersal of both CNS proteins onto equipment, beef hide and personnel. These results demonstrate that despite the rigorous application of current SRM control policies, normal slaughter practices continue to present significant opportunities for CNS material including BSE prion present in the CNS of any sub-clinically infected cattle to contaminate meat entering the human food chain.

Dissemination of central nervous system tissue during the slaughter of cattle in three Irish abattoirs.

Sponge samples were taken from the carcases, meat, personnel and surfaces involved in stunning, slaughter and dressing/boning activities at three abattoirs, and from retail beef products. The samples were examined for the presence of central nervous system (CNS)-specific proteins (syntaxin 1B and/or glial fibrillary acidic protein (GFAP), as indicators of contamination with CNS tissue. Syntaxin 1B and GFAP were detected in many of the sponge samples taken along the slaughter line and in the chill rooms of all three abattoirs; GFAP was also detected in one sample of longissimus muscle (striploin) taken in the boning hall of one of the abattoirs but not in the other two abattoirs or in retail meats.

Anticoagulation, bleeding and blood transfusion practices in Australasian cardiac surgical practice.

We surveyed contemporary Australasian cardiac surgical and anaesthetic practice, focusing on antiplatelet and antifibrinolytic therapies and blood transfusion practices. The cohort included 499 sequential adult cardiac surgical patients in 12 Australasian teaching hospitals. A total of 282 (57%) patients received red cell or component transfusion. The median (IQR) red cell transfusion threshold haemogloblin levels were 66 (61-73) g/l intraoperatively and 79 (74-85) g/l postoperatively. Many (40%) patients had aspirin within five days of surgery but this was not associated with blood loss or transfusion; 15% had clopidogrel within seven days of surgery. In all, 30 patients (6%) required surgical re-exploration for bleeding. Factors associated with transfusion and excessive bleeding include pre-existing renal impairment, preoperative clopidogrel therapy, and complex or emergency surgery. Despite frequent (67%) use of antifibrinolytic therapy, there was a marked variability in red cell transfusion rates between centres (range 17 to 79%, P < 0.001). This suggests opportunities for improvement in implementation of guidelines and effective blood-sparing interventions. Many patients presenting for surgery receive antiplatelet and/or antifibrinolytic therapy, yet the subsequent benefits and risks remain unclear.

Physical fitness profile of elite athletes with intellectual disability.

UNLABELLED: The aim of this study was to investigate the physical fitness profile of high-performance athletes with intellectual disability (ID) in comparison with able-bodied individuals. METHODS: Participants were 231 male and 82 female athletes. All evaluations were done using the EUROFIT physical fitness test. RESULTS: In comparison with population data, both male and female athletes with ID score better for flexibility and upper body muscle endurance, but have similar or lower values for running speed, speed of limb movement, and strength measures. Compared with age-matched physical education students, male athletes with ID score better for running speed and flexibility, and worse for strength. Female athletes with ID score not different from able-bodied individuals for flexibility, running speed, and upper body muscle endurance, but worse for strength measures. Athletes with ID also have poorer cardio respiratory endurance capacity compared with sportive peers without ID. Furthermore, male athletes have a more differentiated profile depending upon their sports discipline, compared with female athletes. CONCLUSION: It can be concluded that high-performance athletes with ID reach physical fitness levels that are equal to or lower than those of able-bodied sportive counterparts. Further research should investigate the importance of reduced muscle strength to be the limiting factor.

Asymmetry in bicycle ergometer pedalling.

The effects of changes in speed and resistance setting on the bilateral symmetry of work output on the bicycle ergometer were studied. The cranks of a Monarch bicycle ergometer were instrumented with foil strain gauges and the bridge outputs were integrated on-line and analyzed by a program running in a Hewlett Packard 2115A computer. Twenty male subjects performed three thirty-second trials at each of nine speed and resistance combinations. Indices of asymmetry from 66-178 were found using kicking dominance (n = 20) and 56-135 using a strength dominance classification (n = 13). Day to day reliability of the index of asymmetry was found to be only 0.47; within day reliability was 0.87 for day one and 0.79 for day two. No significant effects for speed or resistance changes were shown on either day for the strength dominant subjects. When kicking dominance was considered main effects were encountered on both days for speed although there was no clear directional trend. The findings of these experiments have important implications for studies where measurements are made on the lower extremity during cycle ergometer exercise, and for competitive cyclists engaged in endurance competition.

Characterization of proline endopeptidase from skeletal muscle.

Proline endopeptidase was purified from human muscle by anion-exchange chromatography, thiol-affinity chromatography and chromatography on hydroxyapatite. The enzyme gave a single band on polyacrylamide gel electrophoresis. Activity was maximum at pH 7.0-7.5. The molecular weight (by gel filtration) was 69,000. The enzyme hydrolysed benzyloxycarbonyl-Gly-Pro-7-amido-4-methylcoumarin with Km 32 microM. It was inhibited by di-isopropyl phosphofluoridate and 4-hydroxymercuriphenyl sulphate. Bacitracin inhibited at higher concentrations but lower concentrations stimulated the activity. The enzyme activity appeared largely in the soluble fraction following fractionation of rat muscles. Proline endopeptidase activity in rat muscle was unaltered by treatment of the animals with compound 48/80, a mast cell degranulator.

Field test evaluation of aerobic, anaerobic, and wheelchair basketball skill performances.

Forty-six male wheelchair basketball players performed a set of field tests to evaluate aerobic capacity (25 m shuttle run), anaerobic capacity (30s sprint), and six specific wheelchair basketball skills. Overall test-retest reliability (n = 20) ranged from r = 0.65 to r = 0.97. To study the validity (criterion related evidence) of the shuttle run test, heart rate (HR) was recorded for 15 subjects, who also performed a continuous, multistage arm cranking exercise until volitional fatigue. Moderate to high correlations were calculated between shuttle run distances covered (1375 243,6 m) and VO2max (2208+/-461.6 mL/min) and POmax (93.8+/-17.97 W), measured during maximal arm cranking (respectively r = 0.64 and r = 0.87). Maximal HR during shuttle run (174.9+/-16.6 B/min) and arm cranking (169+/-14.21 B/min) were correlated (r = 0.78). High correlations between shuttle run test and anaerobic field tests, however, indicate high implication of anaerobic and wheelchair maneuverability performances. The 30 s sprint test was validated (n = 15) against a Wingate Anaerobic Test (WAnT) on a roller ergometer. Comparing distance (field test: 90+/-6.7 m) with mean power output (WAnT: 852.1+/-234.9 W) the correlation was r = 0.93. Principal components factor analysis identified 'wheelchair propulsion dynamics' and 'eye-hand-coordination' as the underlying constructs of the six skill proficiency measurements, accounting for 80.1% of the variance. In conclusion, the newly developed field test battery is a reliable and valid tool for anaerobic capacity and skill proficiency assessment in wheelchair basketball players.

The use of electrochemically grown polymers on metallized electrodes to reduce electrode fouling in biological matrices.

The use of electrochemically grown polymers has expanded dramatically in the last couple of years, and they are now well established as membranes for immobilizing components. The evidence here for their anti-fouling properties is good. The poly(1,3-diaminobenzene)-covered electrodes performed well in the buffer, urine, plasma and serum samples, but not so well in the blood. The Ru/Rh/Pt, Rh/Rh and the Pt-on-glassy carbon electrodes covered with poly(1,3-diaminobenzene) were the best electrodes in the blood. The Pt disc seemed to exhibit the largest irrepeatability in most of the biological matrices.

Use of a marker organism to model the spread of central nervous system tissue in cattle and the abattoir environment during commercial stunning and carcass dressing.

Due to concerns about a link between variant Creutzfeldt-Jakob disease in humans and similar prion protein-induced disease in cattle, i.e., bovine spongiform encephalopathy (BSE), strict controls are in place to exclude BSE-positive animals and/or specified risk materials including bovine central nervous system (CNS) tissue from the human food chain. However, current slaughter practice, using captive bolt guns, may induce disruption of brain tissues and mobilize CNS tissues into the bovine circulatory system, leading to the dispersion of CNS tissues (including prion proteins) throughout the derived carcass. This project used a marker (antibiotic-resistant) strain of Pseudomonas fluorescens to model the effects of commercial captive bolt stunning procedures on the movement of mobilized CNS material within slaughtered animals and the abattoir environment. The marker organism, introduced by injection through the bolt entry aperture or directly using a cartridge-fired captive bolt, was detected in the slaughter environment immediately after stunning and in the abattoir environment at each subsequent stage of the slaughter-dressing process. The marker organism was also detected on the hands of operatives; on slaughter equipment; and in samples of blood, organs, and musculature of inoculated animals. There were no significant differences between the results obtained by the two inoculation methods (P < 0.05). This study demonstrates that material present in, or introduced into, the CNS of cattle during commercial captive bolt stunning may become widely dispersed across the many animate and inanimate elements of the slaughter-dressing environment and within derived carcasses including meat entering the human food chain.

The use of a marked strain of Pseudomonas fluorescens to model the spread of brain tissue to the musculature of cattle after shooting with a captive bolt gun.

AIMS: The aim of this study was to use a marked strain of Pseudomonas fluorescens to model the spread of central nervous system (CNS) tissue in cattle following captive bolt stunning. METHODS AND RESULTS: The marked organism was introduced by injection through the captive bolt aperture immediately after stunning and was subsequently detected in a wide range of derived tissues, including blood, organs, and the musculature of the entire forequarters of test animals. This was dependent on the use of high concentrations of the organism that were recovered sufficiently and rapidly to minimize the bactericidal properties of the circulatory system. These results suggest that a marked organism could potentially be used to model the effects of captive bolt stunning on the dissemination of CNS tissue from the brain. CONCLUSIONS: These results indicate that current commercial methods of captive bolt stunning may induce widespread and significant mobilization of CNS tissue within beef carcasses. This may lead to the widespread dissemination of such materials within meat destined for human consumption. SIGNIFICANCE AND IMPACT OF THE STUDY: In the absence of rapid, simple and sufficiently sensitive methods for the direct detection of prion in commercially slaughtered animals, marked organisms can provide useful models in studies of the dissemination kinetics of prion disease in captive bolt stunned animals.