Investigation of the pathophysiology of bacterial mastitis using precision-cut bovine udder slices.

Mastitis in cattle is a major health problem as well as incurring high costs for the dairy industry. To assess the suitability of precision-cut bovine udder slices (PCBUS) for bovine mastitis studies, we infected PCBUS with 2 different Staphylococcus aureus strains. Accordingly, we investigated both the tissue response to infection based on immune mediators at the mRNA and protein levels and the invasion of bacteria within the tissue. The studied proteins represent immune mediators of early inflammation [IL-1ß, tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2)] and showed a time-dependent increase in concentration. Infection of PCBUS with S. aureus resulted in increased expression of proinflammatory cytokines and chemokines such as TNF-α, C-C motif chemokine ligand 20 (CCL20), IL-1ß, IL-6, and IL-10, but not C-X-C motif chemokine ligand 8 (CXCL8), lingual antimicrobial peptide (LAP), or S100 calcium binding protein A9 (S100A9) at the mRNA level. To compare the data acquired with this model, we carried out investigations on primary bovine mammary epithelial cells. Our results showed that the immune responses of both models-PCBUS and primary bovine mammary epithelial cells-were similar. In addition, investigations using PCBUS enabled us to demonstrate adherence of bacteria in the physiological cell network. These findings support the use of PCBUS in studies designed to further understand the complex pathophysiological processes of infection and inflammation in bovine mastitis and to investigate alternative therapies for mastitis.

Comparative evaluation of 6A and 5A chargers for Sonnenschein gel cell batteries used in wheelchairs.

Laboratory tests were conducted to determine suitable battery charges for recharging Sonnenschein dryfit A200 36Ah gel cell batteries. Five commercially made chargers were tested on a standardised pair of batteries and were individually assessed for their ability to satisfy Australian Standards. From these results it was possible to select the chargers usable on Sonnenschein A200 dryfit 36Ah gel cell batteries. The effect of charging regime on battery cycle life was not included.

Technology for people with disabilities: a survey of needs.

A good understanding of the needs, desires, and capabilities of individuals with disabilities is critical if rehabilitation workers are to promote optimum quality of life. This survey was undertaken to determine the needs of a population of adults with disabilities as a result of neurological trauma or disease. We looked at communication, seating, mobility, environmental control, education, and leisure. Consideration of assistive technology's role in meeting these needs was achieved by an experienced Technology Access Team comprising a physiotherapist, occupational therapist, and speech pathologist in screening consenting residents. The initial needs survey identified that 37% of clients in the study had problems with verbal communication, 62% with cognition, and 52% with seating. Assessments for electric wheelchairs were required by 21.5% of clients while 30.7% had problems with hand function for accessing. Further assessment for equipment and/or training was recommended in 123 (70%) of the 163 participants. These findings have implications for management, including raising awareness of technology's benefits. There are also implications regarding staff knowledge and specialist skills required to identify needs and technological solutions. Preliminary recommendations await validation as individual's requirements are further investigated.

Isometric joystick: a study of control by adolescents and young adults with cerebral palsy.

This research was undertaken to determine the best wheelchair driving method for clients with cerebral palsy who were experiencing difficulties using displacement joysticks. The hypothesis was that adolescents with cerebral palsy would perform better in a tracking task using an isometric joystick (which has no moving parts) than a displacement joystick of the type used in commercial wheelchair controllers. A series of single subject case studies was performed in which the activating force of the isometric joystick was individualised for each subject. Comparative evaluation of the isometric joystick and a displacement joystick was then carried out. Results indicate that performance using the displacement joystick was superior to performance with the isometric joystick for the able-bodied subject and four of the five subjects with cerebral palsy. One of the subjects showed significantly better performance on the displacement joystick using his hand, and no significant difference between joysticks using his foot. The remaining subject, who used his foot, showed no significant difference between joysticks. These findings suggest that subjects with cerebral palsy with prior experience using a displacement joystick do not appear to benefit by the use of an isometric joystick compared to a displacement joystick. No difference in the use of the two joysticks was found for subjects with cerebral palsy who had no prior experience using a joystick. This suggests that an isometric joystick is an option for people beginning to learn to drive an electric wheelchair.

Toy Control Program evaluation.

The Toy Control Program for the Apple IIe microcomputer is a software and hardware package developed for the training of single-switch scanning skills. The specially designed scanning programs provide on screen visual feedback and activate a battery-powered toy to reinforce performance. This study examined whether the training of preschool subjects in single-switch scanning skills with the Toy Control Program would result in increased task completion scores and increased levels of attention to task, as compared with conditions of toy activation only and microcomputer programs with screen reinforcement only. The results showed that the subjects paid significantly more attention to the toys as reinforcers (p less than .01). No significant difference was found for the performance results of the three conditions. These findings support the use of a program like the Toy Control Program, which integrates the instructional capabilities of a computer with the reinforcement potential of a toy and the creativity of a therapist.

Wheelchair occupant restraints in motor vehicles.

The issue of safety for wheelchair users in motor vehicles has been raised in Australia by parents of young people with disabilities. Investigations revealed that wheelchair users were not covered by any legislated safety requirements, and each case received special dispensation from compliance with regulations covering the able-bodies population. Dynamic testing of restraint systems at the University of Michigan had revealed that existing systems were unsafe. Dynamic tests confirmed those findings on systems used at that time in Australia. Testing led to the design, development and marketing of a new wheelchair occupant and restraint system which remains a system of choice for use by organisations where the same people use the same buses in the same position each day. Australian Standard 2942-1987, Wheelchair Occupant Restraint Assemblies for Use in Motor Vehicles, has since been developed. It establishes design and performance requirements for these restraints and includes details of dynamic testing procedures. This paper describes the development of the above restraint system and the subsequent Australian Standard.

Comparative evaluation of chargers for wheelchair gel cell batteries.

This study was undertaken as part of our ongoing work to upgrade wheelchair quality. Laboratory tests were conducted to determine which battery chargers would ensure that the user's batteries are fully charged each night and also ensure that the battery lifetime was not diminished. Five commercial chargers were tested on a standardised pair of gel cell batteries of a type commonly used to power wheelchairs. Results of this study indicate a clear preference between chargers. As a result, we have changed the chargers we purchase. We anticipate that our clients will now experience longer life from their wheelchair gel cell batteries.

International wheelchair standards: a study of costs and benefits.

We hypothesized that extra costs incurred in meeting the requirements of wheelchair standards are recouped within the life of the wheelchair. We selected standards-quality and non-standards-quality electric wheelchairs of the same make and subjected them to accelerated life tests in a laboratory to simulate 1 year's active use. Expenses and lost time incurred due to breakdowns were monitored, and the costs of upgrading were documented. Our results support the hypothesis, within the limits imposed by the availability of only a small number of makes of electric wheelchairs of recognized standards quality. The significance of this finding is that wheelchair standards can be used to upgrade wheelchair quality in a cost-effective manner.

Functional electrical stimulation for upper limb strengthening in traumatic quadriplegia.

The hypothesis of this study was that the functional electrical stimulation (FES)-assisted exercise of partially paralyzed arm muscles would result in significantly greater muscle strength in the arms of spinal cord injured quadriplegics than equal periods of conventional isotonic exercise. Single muscles were studied in seven subjects in a crossover design consisting of equal periods of FES-assisted exercise and conventional exercise. It was concluded that for these subjects using this exercise regime, neither FES-assisted exercise nor conventional exercise produced improvements in maximum voluntary force that were either statistically or functionally significant. The results, although disappointing, have helped these subjects to be more realistic about the potential therapeutic benefits of FES.

Testing of gel-electrolyte batteries for wheelchairs.

A simple test rig was developed to measure the capacity of the lead-acid gel-electrolyte batteries used to power wheelchairs. Results of 166 tests revealed a wide scatter of battery life with different users and also showed that, in many cases, the two batteries used in a wheelchair became unequal in charge capacity after some time in use. It is recommended that pairs of batteries should be charged in series to overcome this problem.

Development of an Australian standard for wheelchair occupant restraint assemblies for motor vehicles.

An Australian Standard for Wheelchair Occupant Restraint Assemblies for Motor Vehicles has been produced. Titled Australian standard 2942-1987, Wheelchair Occupant Restraint Assemblies for Use in Motor Vehicles, it establishes design and performance requirements for these restraints, and includes details of dynamic testing procedures. Under the Standard, a lap belt is the basic occupant restraint required with the wheelchair restrained independently of the occupant. The Standard, instead of specifying a "standard" design for wheelchair occupant restraint assemblies, is intended to ensure effective crash protection for wheelchair occupants with a minimum of restriction on the design of restraints. It requires that instructions for installation and use of restraints be provided. Also included in the Standard is an advisory section providing general information for restraint users such as the types of wheelchairs best suited for use in vehicles. This appears to be the first national Standard for wheelchair occupant restraint assemblies for motor vehicles, and may well form the basis of similar standards elsewhere.

Skill evaluator and trainer for electrically operated devices: an evaluation of the SET.

Our hypothesis was that the abilities of disabled people to control electrically-powered assistive devices could be reliably and objectively assessed by means of a portable, lightweight and inexpensive device, the Skill Evaluator and Trainer (SET), and that training on the SET would improve skill. Our approach was to use SET with a variety of interfaces and subject groups. SET produced a valid assessment of the skills of disabled people with particular interfaces, it improved skills when used as a training aid, and it was well accepted by clients and therapists.

Progression of equinus deformity in Duchenne muscular dystrophy.

This study investigated the influence of orthoses, regular passive stretching, and surgery on progression of equinus deformity in Duchenne muscular dystrophy. The extent of passive dorsiflexion on the right foot of ambulant and wheelchair-ambulatory patients was measured monthly with an electronic ankle goniometer calibrated to an accuracy of 1 degree. The mean rate of equinus progression was 0.4 degree per month during the 12-month study. Progression was less in those boys who had prior surgery and were older. Progression was slowest during the first five months of the study (when night splints were used more frequently) and greatest during a long vacation when regular passive stretching by physiotherapists and supervision of splinting were unavailable. These results, although based on a limited patient sample size, indicate that gains from use of orthoses and passive stretching can be lost in the absence of professional supervision.

Lumbar extension in Duchenne muscular dystrophy: effect on lateral curvature.

The purpose of this study was to investigate the hypothesis that a lumbar pad producing extension of the lumbar spine is of value in posture support seats for children with Duchenne muscular dystrophy. Our method was to establish whether or not an increase in lumbar lordosis produced any increase in resistance to static lateral curvature of the supine lumbar spine. Nine boys with Duchenne muscular dystrophy were studied at an age when they were about to go into a wheelchair or had recently become wheelchair mobile. In each case the child lay supine on low-friction material on an x-ray table while the spine was flexed first to the right and then to the left, with and without a lumbar pad, by a predetermined force. The degree of lateral curvature was measured from anteroposterior radiographs. While lateral forces were applied when the boys were supine rather than seated, the results failed to show a difference in curvature with or without the lumbar pad.

Plasma concentrations of beta-carotene and canthaxanthin during and after stopping intake of a combined preparation.

During 17 days two groups of 6 and 8 volunteers of the Department of Dermatology ingested 4 and 6 capsules per day of carotenoids (10 mg beta-carotene + 15 mg canthaxanthin per capsule; Phenoro). Heparinized blood was collected twice a week until day 21 and then weekly until day 77. Concentrations of beta-carotene and canthaxanthin in plasma were analyzed by high-performance liquid chromatography during 77 days. Plasma levels of carotenoids were higher in group 2 (6 capsules) than in group 1 (4 capsules) but reached maximum concentrations within the same time. Hence, therapeutic plasma levels of beta-carotene were reached earlier in group 2. According to blood levels, group 2 could be clearly divided in low and high responders. In contrast to canthaxanthin, beta-carotene exhibited a biphasic decline in both groups, with a monophasic asymptotic decrease which was expressed clinically by a pronounced orange to yellow pigmentation of the skin.

Hand function in cerebral palsy: the effect of hip-flexion angle.

This study tested the hypothesis that increasing hip flexion above 90 degrees would improve hand function in seated cerebral-palsied children with extensor spasticity. Hand function was measured objectively at four hip-flexion angles in an experimental group and a control group. The results showed no significant differences in performance. However, seat angles 10 degrees and 20 degrees above horizontal were least often described as uncomfortable. The results show that, contrary to current belief, increasing hip-flexion angle in seating for a child with cerebral palsy and extensor spasticity appears to have no effect on hand function.

Orthotic management of scoliosis in Duchenne muscular dystrophy.

This study investigates the effectiveness of spinal supports and seating systems in retarding the progress of spinal curvature in Duchenne muscular dystrophy. The approach was to take six monthly radiographs of children with this disease attending the Regency Park Centre sitting in their wheelchairs with their usual spinal supports. Scoliosis progressed from a mean value of approximately 10 degrees for children under 12 years to a value of the order of 75 degrees by the age of 16 to 18 years. The rate of progression peaked at an average of more than 1 degree per month between 14 and 18 years. The curvatures observed using modular seats, spinal jackets and custom-molded seats were not significantly different from those observed using unmodified wheelchair seats.

Chariots of freedom: wheeled mobility at regency park centre for young disabled, South australia.

This paper concerns wheeled mobility aids, or 'Chariots of Freedom'. Wheelchairs are the most commonly used wheeled mobility aids. The rationale for mobility management at Regency Park Centre for Young Disabled is based on the research findings of others, research at the Centre into seating for children with cerebral palsy and children with Duchenne muscular dystrophy, and our development of a Skill Evaluator and Trainer, and a crashworthy restraint for wheelchair occupants in motor vehicles. In summary, wheeled mobility aids, and wheelchairs in particular, while entailing responsibilities, present a form of liberation from dependence for disabled children.