Laserlight visual cueing device for freezing of gait in Parkinson's disease: a case study of the biomechanics involved.

BACKGROUND: Freezing of gait (FOG) is a serious gait disorder affecting up to two-thirds of people with Parkinson's disease (PD). Cueing has been explored as a method of generating motor execution using visual transverse lines on the floor. However, the impact of a laser light visual cue remains unclear. OBJECTIVE: To determine the biomechanical effect of a laser cane on FOG in a participant with PD compared to a healthy age- and gender-matched control. METHODS: The participant with PD and healthy control were given a task of initiating gait from standing. Electromyography (EMG) data were collected from the tibialis anterior (TA) and the medial gastrocnemius (GS) muscles using an 8-channel system. A 10-camera system (Qualisys) recorded movement in 6 degrees of freedom and a calibrated anatomical system technique was used to construct a full body model. Center of mass (COM) and center of pressure (COP) were the main outcome measures. RESULTS: The uncued condition showed that separation of COM and COP took longer and was of smaller magnitude than the cued condition. EMG activity revealed prolonged activation of GS, with little to no TA activity. The cued condition showed earlier COM and COP separation. There was reduced fluctuation in GS, with abnormal, early bursts of TA activity. Step length improved in the cued condition compared to the uncued condition. CONCLUSION: Laserlight visual cueing improved step length beyond a non-cued condition for this patient indicating improved posture and muscle control.

The impact of the AFDC and Food Stamp programs on child nutrition: empirical evidence from New Orleans.

This study tests the hypotheses that the participation in the Aid to Families with Dependent Children (AFDC) and Food Stamp programs has a positive impact on children's nutritional status, after controlling for other potentially important household- and individual-level characteristics. The analysis is based on the responses of a health facility survey of 246 pairs of low-income mothers and children in New Orleans. The results indicate that participation in the AFDC and Food Stamp programs is associated with increased anthropometric status of children, but the foods consumed by children in families receiving welfare benefits were of significantly lower nutritional value than foods consumed by other children. Among the study's conclusions are the following: (1) in this low-income setting, AFDC and Food Stamp benefits are associated with higher food expenditures, higher anthropometric levels, but inferior diets, and (2) female-headed households spend more on food expenditures than other households, after controlling for other individual- and household-level characteristics.

Interior structure of neptune: comparison with uranus.

Measurements of rotation rates and gravitational harmonics of Neptune made with the Voyager 2 spacecraft allow tighter constraints on models of the planet's interior. Shock measurements of material that may match the composition of Neptune, the so-calied planetary ;;ice,'' have been carried out to pressures exceeding 200 gigapascals (2 megabars). Comparison of shock data with inferred pressure-density profiles for both Uranus and Neptune shows substantial similarity through most of the mass of both planets. Analysis of the effect of Neptune's strong differential rotation on its gravitational harmonics indicates that differential rotation involves only the outermost few percent of Neptune's mass.

Differential susceptibility to gentamicin ototoxicity between albino and pigmented guinea pigs.

The known chemical affinity of melanin pigment for aminoglycoside antibiotics has led to the suggestion that higher concentrations of these drugs will bind to the pigmented inner ear and produce greater ototoxicity compared to the nonpigmented albino cochlea. Although this has provided a compelling hypothesis, results from the few investigations to address this question have been equivocal. In the present study, cochlear microphonic (CM) thresholds were recorded from albino and pigmented guinea pigs both before and two weeks after exposure for 14 consecutive days to 100 mg/Kg gentamicin. Cochleae were dissected and half-turn segments prepared for surface examination of the organ of Corti. After gentamicin exposure, threshold shifts averaged a statistically reliable 33 dB in albinos and 19 dB for the pigmented animals. Anatomical studies revealed a significant 44% mean outer hair cell loss in albinos compared to a 21% loss in the pigmented inner ears. The results showed that albinos display greater ototoxicity from gentamicin than do pigmented guinea pigs. Aminoglycosides are known to exert toxicity through interaction with polyphosphoinositides found in high concentrations in the inner ear. Cochleae in both albino and pigmented animals appear to possess significant phospholipid concentrations and bind toxic levels of these drugs independent of inner ear pigment content. However, evidence showing that melanin can inhibit aminoglycoside activity in vitro suggests that, once these drugs bind to pigmented tissue, they may undergo inactivation in a manner unavailable to the nonpigmented albino cochlea. The present results are consistent with the possibility that cochlear melanin may inhibit gentamicin activity in vivo and decrease the severity of aminoglycoside ototoxicity in the pigmented inner ear.

A model animal therapy program for mental health settings.

This paper describes the structure and function of a program of animal therapy used with hospitalized psychiatric patients as part of a comprehensive therapy milieu. It begins with identification of some common psychological needs of psychiatric patients and continues with a discussion of ways in which therapeutic recreation programs such as this can address these common needs and facilitate their development in psychotherapy. In addition, potential modifications are explored as a means of adapting the principles of this model to accommodate the resources of virtually any mental health or recreational therapy program.