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Jonathan Hill

Publications and source records attributed to Jonathan Hill.

4 recordsLinked to original sources

Pulsed short-wave diathermy effects on human fibroblast proliferation.

OBJECTIVES: To investigate the influence of pulsed short-wave diathermy (PSWD) on fibroblast and chondrocyte cell proliferation rates and to establish the influences of different dosages applied. DESIGN: Four single-blind trials. SETTING: Laboratory, in vitro study. SPECIMENS: Human adult dermal fibroblast and chondrocyte cells were plated at known concentrations and incubated for 5 days. INTERVENTION: Exposure to PSWD, twice daily, on days 2, 3, and 4. MAIN OUTCOME MEASURE: After crystal violet staining (day 5), optical density (cell number) was determined spectrophotometrically. RESULTS: PSWD, given at mean power of 48W for 10 minutes, increased fibroblast proliferation compared with control groups (P<.001). There was a relationship between cell proliferation and the amount of energy given (P<0.001). The optimal mean power for proliferation was estimated to be 13.8W. While keeping mean power constant at 6W, altering pulse duration and pulse repetition rate dosage parameters did not have a significant effect on proliferation (P=.519). Chondrocyte proliferation also increased with PSWD exposure of 6W at 10 minutes duration (P=.015). In addition, treatment time was significantly associated with chondrocyte proliferation (P<.001). CONCLUSION: PSWD is associated with increased rates of fibroblast and chondrocyte proliferation in vitro, which is dose dependent. These results contribute to an understanding of the physiologic mechanisms underlying the therapeutic effects of PSWD.

Adult↗

Biological, psychological and social processes in the conduct disorders.

BACKGROUND: This paper reviews recent evidence on the causes and maintenance of aggressive and disruptive behaviours in childhood and adolescence. It considers the relative merits of several different ways of conceptualising such problems, in relation to the contribution of biological, psychological and social factors. METHOD: It focuses on conduct problems appearing in young childhood, which greatly increase the likelihood of persistent antisocial behaviours in adolescence and adult life in association with wider interpersonal and social role impairments. It considers the contribution of individual factors, including impaired verbal skills, deficits in executive functions, and an imbalance between behavioural activation and inhibition systems. These are viewed in interaction with commonly associated environmental disadvantages such as hostile or intrusive parenting. The roles of attributional biases, unrealistic self-evaluations, and insecure attachment are considered in relation to affect regulation, and effective social action. The contributions of the wider social environments of peers, neighbourhood and socio-economic conditions are evaluated. CONCLUSIONS: The paper concludes that, although considerable progress has been made over the past ten years, there is a need to further refine our conceptualisation of the behaviours to be explained, to develop a coherent theory of the causal and maintaining processes, and to carry out prospective studies with adequate numbers of high risk children.

Adolescent↗

A comparative study of telephone versus onsite completion of the WOMAC 3.0 osteoarthritis index.

OBJECTIVE: Outcome assessment in clinical trials using the Western Ontario and McMaster University (WOMAC 3.0) Osteoarthritis Index is traditionally achieved through self-administration of the Index. However, in other areas of clinical measurement, telephone administration has been shown to be a reliable method of acquiring data that are both accurate and complete. To address this issue in knee osteoarthritis (OA), we conducted a comparative study of telephone administration by interviewer of WOMAC LK3.0 versus onsite self-completion at the hospital. METHODS: Fifty consenting patients with knee OA were randomized to complete the WOMAC LK3.0 Index by telephone interview one day, followed by onsite completion the following day, or vice versa. Neither patients nor interviewers had access to any prior scores. RESULTS: The mean age of the 50 patients was 66.3 years (range 44-82); 34 (68%) were female and 16 (32%) male. There was excellent agreement between the mean office and telephone scores, with mean differences for the WOMAC LK3.0 pain, stiffness, and function subscale scores and total score of 0.09, 0.12, 0.78, and 0.98, respectively. These differences were well within the respective protocol defined equivalence criteria of +/- 1.7, +/- 0.9, +/- 6.4, and +/- 9.1, and represented differences from office scores of 0.9, 2.6, 2.4, and 2.2%, respectively. CONCLUSION: The use of telephone interviews for the WOMAC LK3.0 Index is a valid method of obtaining OA outcome measurements. These observations have important implications for designing data acquisition strategies for future OA clinical trials and for longterm observational studies.

Activities of Daily Living↗