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Selected AbstractsManagement of TMD: evidence from systematic reviews and meta-analysesJOURNAL OF ORAL REHABILITATION, Issue 6 2010T. LIST Summary, This systematic review (SR) synthesises recent evidence and assesses the methodological quality of published SRs in the management of temporomandibular disorders (TMD). A systematic literature search was conducted in the PubMed, Cochrane Library, and Bandolier databases for 1987 to September 2009. Two investigators evaluated the methodological quality of each identified SR using two measurement tools: the assessment of multiple systematic reviews (AMSTAR) and level of research design scoring. Thirty-eight SRs met inclusion criteria and 30 were analysed: 23 qualitative SRs and seven meta-analyses. Ten SRs were related to occlusal appliances, occlusal adjustment or bruxism; eight to physical therapy; seven to pharmacologic treatment; four to TMJ and maxillofacial surgery; and six to behavioural therapy and multimodal treatment. The median AMSTAR score was 6 (range 2,11). Eighteen of the SRs were based on randomised clinical trials (RCTs), three were based on case,control studies, and nine were a mix of RCTs and case series. Most SRs had pain and clinical measures as primary outcome variables, while few SRs reported psychological status, daily activities, or quality of life. There is some evidence that the following can be effective in alleviating TMD pain: occlusal appliances, acupuncture, behavioural therapy, jaw exercises, postural training, and some pharmacological treatments. Evidence for the effect of electrophysical modalities and surgery is insufficient, and occlusal adjustment seems to have no effect. One limitation of most of the reviewed SRs was that the considerable variation in methodology between the primary studies made definitive conclusions impossible. [source] Laser stimulation of single auditory nerve fibers,,§¶,THE LARYNGOSCOPE, Issue 10 2010Philip D. Littlefield MD Abstract Objectives/Hypothesis: One limitation with cochlear implants is the difficulty stimulating spatially discrete spiral ganglion cell groups because of electrode interactions. Multipolar electrodes have improved on this some, but also at the cost of much higher device power consumption. Recently, it has been shown that spatially selective stimulation of the auditory nerve is possible with a mid-infrared laser aimed at the spiral ganglion via the round window. However, these neurons must be driven at adequate rates for optical radiation to be useful in cochlear implants. We herein use single-fiber recordings to characterize the responses of auditory neurons to optical radiation. Study Design: In vivo study using normal-hearing adult gerbils. Methods: Two diode lasers were used for stimulation of the auditory nerve. They operated between 1.844 ,m and 1.873 ,m, with pulse durations of 35 ,s to 1,000 ,s, and at repetition rates up to 1,000 pulses per second (pps). The laser outputs were coupled to a 200-,m-diameter optical fiber placed against the round window membrane and oriented toward the spiral ganglion. The auditory nerve was exposed through a craniotomy, and recordings were taken from single fibers during acoustic and laser stimulation. Results: Action potentials occurred 2.5 ms to 4.0 ms after the laser pulse. The latency jitter was up to 3 ms. Maximum rates of discharge averaged 97 ± 52.5 action potentials per second. The neurons did not strictly respond to the laser at stimulation rates over 100 pps. Conclusions: Auditory neurons can be stimulated by a laser beam passing through the round window membrane and driven at rates sufficient for useful auditory information. Optical stimulation and electrical stimulation have different characteristics; which could be selectively exploited in future cochlear implants. Laryngoscope, 2010 [source] Use, misuse and extensions of "ideal gas" models of animal encounterBIOLOGICAL REVIEWS, Issue 3 2007John M. C. Hutchinson Abstract Biologists have repeatedly rediscovered classical models from physics predicting collision rates in an ideal gas. These models, and their two-dimensional analogues, have been used to predict rates and durations of encounters among animals or social groups that move randomly and independently, given population density, velocity, and distance at which an encounter occurs. They have helped to separate cases of mixed-species association based on behavioural attraction from those that simply reflect high population densities, and to detect cases of attraction or avoidance among conspecifics. They have been used to estimate the impact of population density, speeds of movement and size on rates of encounter between members of the opposite sex, between gametes, between predators and prey, and between observers and the individuals that they are counting. One limitation of published models has been that they predict rates of encounter, but give no means of determining whether observations differ significantly from predictions. Another uncertainty is the robustness of the predictions when animal movements deviate from the model's assumptions in specific, biologically relevant ways. Here, we review applications of the ideal gas model, derive extensions of the model to cover some more realistic movement patterns, correct several errors that have arisen in the literature, and show how to generate confidence limits for expected rates of encounter among independently moving individuals. We illustrate these results using data from mangabey monkeys originally used along with the ideal gas model to argue that groups avoid each other. Although agent-based simulations provide a more flexible alternative approach, the ideal gas model remains both a valuable null model and a useful, less onerous, approximation to biological reality. [source] Meeting the Need for Personal Care among the Elderly: Does Medicaid Home Care Spending Matter?HEALTH SERVICES RESEARCH, Issue 1p2 2008Peter Kemper Objective. To determine whether Medicaid home care spending reduces the proportion of the disabled elderly population who do not get help with personal care. Data Sources. Data on Medicaid home care spending per poor elderly person in each state is merged with data from the Medicare Current Beneficiary Survey for 1992, 1996, and 2000. The sample (n=6,067) includes elderly persons living in the community who have at least one limitation in activities of daily living (ADLs). Study Design. Using a repeated cross-section analysis, the probability of not getting help with an ADL is estimated as a function of Medicaid home care spending, individual income, interactions between income and spending, and a set of individual characteristics. Because Medicaid home care spending is targeted at the low-income population, it is not expected to affect the population with higher incomes. We exploit this difference by using higher-income groups as comparison groups to assess whether unobserved state characteristics bias the estimates. Principal Findings. Among the low-income disabled elderly, the probability of not receiving help with an ADL limitation is about 10 percentage points lower in states in the top quartile of per capita Medicaid home care spending than in other states. No such association is observed in higher-income groups. These results are robust to a set of sensitivity analyses of the methods. Conclusion. These findings should reassure state and federal policymakers considering expanding Medicaid home care programs that they do deliver services to low-income people with long-term care needs and reduce the percent of those who are not getting help. [source] | ||||||||||