Genetic and cellular features of ataxia telangiectasia

Ataxia telangiectasia (AT) is a developmental disorder in which many organ systems are affected. The children are recognized by a progressive cerebellar deterioration. The gene for AT has now been localized to a region of chromosome 11q22-23 of no more than 3Mb in size and its product appears to be involved directly or indirectly in some form of DNA recombination. Patients and their cells are unusually sensitive to ionizing radiation and various radiometric drugs. Observations on the progressive nature of the disorder, with loss of selected cells or failure to develop normally, might be compatible with the pathological effect of an inability to correctly regulate apoptosis in some cell lineages. While this is an intriguing speculation there is, at present, no evidence for such a defect in AT.

Cultured skin keratinocytes from both normal individuals and basal cell naevus syndrome patients are more resistant to gamma-rays and UV light compared with cultured skin fibroblasts

Measurement of colony-forming ability following exposure to gamma-rays was performed on cultured skin keratinocytes and skin fibroblasts obtained from normal individuals, basal cell naevus syndrome patients (BCNS) and ataxia telangiectasia (A-T) patients. The most striking observation was the radiation resistance of 8/8 keratinocyte strains compared with fibroblasts whether from BCNS patients or normals. The single A-T keratinocyte cell strain showed the same radiosensitivity as A-T fibroblast cell strains. The differential survival of keratinocytes and fibroblasts was also observed following exposure to 254 nm UV light. The survival curves of SV40 immortalized keratinocytes and retinoblasts derived from normal individuals or BCNS patients showed large shoulder regions following exposure to gamma-rays or 254 nm UV light. An increased D37 rather than an increased D0 was therefore the feature of such curves. This contrasted with the SV40 immortalized A-T keratinocytes or fibroblasts which showed a minimal shoulder effect and an increased D0. No difference in survival was observed between BCNS and normal cells following exposure to either UV or gamma-rays.

Neuroleptic prescribing to the community elderly in Nottingham

DESIGN

A cross-sectional pilot survey of computerized prescribing databases and written general practitioner records. Data were abstracted by the first author using a standard proforma.

SETTING

Six out of 12 general practices situated in an area of north Nottingham known to have a high density of residential and nursing homes cooperated with the exercise (one was excluded because it lacked a computer system, one because the principal had a specialist commitment to old age psychiatry and four were self-excluded).

PATIENTS

Patients recorded as receiving repeat prescriptions of oral preparations of thioridazine, chlorpromazine, promazine, haloperidol or trifluoperazine.

MEASURES

Point prevalence rates of neuroleptic repeat prescribing classed by age group and, in the case of the elderly, residential status. For elderly recipients: median (range) duration on neuroleptics, median (range) time since last review and numbers (percentages) having various characteristics.

RESULTS

Elderly patients were found to be more likely consumers of neuroleptic medication than their younger counterparts. If these results are extrapolated nationwide, then approximately half the patients receiving repeat prescriptions for the commonest oral neuroleptics emerge as elderly and of these about half are in nursing/residential care. Patients in nursing/residential homes suffering dementia formed the largest group of recipients, but have the least monitoring by psychiatric teams.

CONCLUSION

The result highlight a need for a close partnership between primary care, community care facilities and old age psychiatric teams to ensure adequate monitoring and the implementation of psychological strategies to minimize their use.

Analysis of touch used by occupational therapy practitioners in skilled nursing facilities

Instrumental touch is identified as having purposeful physical contact in order to complete a task. Expressive touch is identified as warm, friendly physical contact and is not solely for performing a task. Expressive touch has been associated with improved client status, increased rapport and greater gains made during therapy. The purpose of the study was to observe the frequency of expressive and instrumental touch utilized by an occupational therapist during an occupational therapy session. Thirty-three occupational therapy professionals, including occupational therapists and occupational therapy assistants, employed at skilled nursing facilities in southwest Florida were observed. Data were collected on the Occupational Therapy Interaction Assessment. The results of the data analysis showed a positive relationship between the gender of the therapist and the frequency of expressive touch. The data also showed that a large majority of touches were instrumental touch and pertained to functional mobility. The results of the study can contribute to a better understanding of the holistic aspects of occupational therapy. By the use of more expressive touch, occupational therapy practitioners may have a positive, beneficial effect on both the client and the therapy process as a whole. Further research is needed to determine the effect an occupational therapy setting has on the frequency of instrumental and expressive touch. A larger sample size and a distinction between evaluation and treatment sessions would benefit future studies.

A systems-based assessment of Palestine's current and future infrastructure requirements

The occupied Palestinian territories of West Bank and Gaza Strip are currently experiencing many challenges in the provision of infrastructure services for their inhabitants. This includes an undersupply of infrastructure services across multiple sectors - an issue exacerbated by population growth, increasing urbanisation, economic growth and climate change. We address this challenge by providing a systems-based assessment of Palestine's infrastructure requirements and identifying broad strategies for how those needs might be met. This assessment involved four key components including: 1) defining and assessing the current system and planned infrastructure investments; 2) assessing potential future demand for infrastructure services; 3) identifying alternative strategies for future infrastructure provision beyond planned investments; and 4) analysing the performance of each strategy against a series of key performance indicators. Results from the assessment highlight the magnitude of the current and future need for urgent infrastructure investment in Palestine. The most immediate need is to alleviate the water crises in Gaza Strip, which will require at least twice as much water infrastructure investment over the coming decade than is currently in the pipeline, even if the goal is only to achieve the most basic World Health Organisation water availability requirements. To move beyond this protracted state of crises will then require a doubling of investments across all sectors to bring Palestine up to the standards of services already enjoyed by its neighbours. Such investments can have even greater impact on delivery of infrastructure services through the strategic use of interdependencies between infrastructure sectors, such as water re-use and energy-from-waste. In the pursuit of global sustainable development, the systems-based approach presented here provides an important first step in the assessment of infrastructure needs and opportunities for any country. It is particularly important for states like Palestine where key resources, such as water and energy, are so acutely constrained.

Student perspectives on learning in a prepaid group practice

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A comparison of constant feeding with bouts of fasting-refeeding at three levels of nutrition in the rat

To investigate whether intermittent fasting alters subsequent utilization of ingested energy, we compared, in six groups of 450-g male Wistar rats, two modalities of food delivery: constant (CO) vs fasting for 3 days and refeeding for 7 days (F/RF). Both modalities were investigated at three planes of nutrition (100, 60 and 40 percent of ad libitum). The F/RF groups were offered, during the 7 days of refeeding, the same amount of food as the CO groups were offered in 10 days. With both 60 and 40 percent food restriction, there were no differences in body weight, body composition, or energy utilization between the F/RF and the CO groups after 4 (40 days) or 8 (80 days) cycles of fasting-refeeding. However, at both 40 and 80 days of study, lipoprotein lipase (LPL) activity was significantly higher in F/RF rats than in CO rats at all three planes of nutrition. Because 100 percent F/RF rats did not eat all food available during each refeeding period, a second experiment was conducted. Rats were fasted for 3 days then refed ad libitum until they reached the weights of 100 percent CO rats. The two groups did not differ in body weight, food intake, body composition or LPL activity after 4 (40 days) fasting-refeeding cycles. Thus, weight cycling produced by repeated bouts of fasting-refeeding did not result in increased efficiency of energy utilization. However, the combination of fasting-refeeding and overall caloric restriction produced greater LPL activity than constant food restriction. It has not been determined whether this elevated LPL activity would affect lipid accumulation upon ad-libitum refeeding.

Application of a simple multiplicative spatio-temporal stream water quality model to the river Conwy, North Wales

We use a simple multiplicative spatio-temporal model to describe variability in a sequence of water quality monitoring data from headwater streams in the Conwy catchment, North Wales. The spatial component of the model treats concentrations as due to simple mixing of a small number of distinct source types, each associated with particular upstream catchment characteristics. The temporal component allows concentration variability due to seasonal or hydrological change. We apply the model using three candidate catchment characteristic classifications to generate mixing concentrations, and a seasonal component to describe temporal variability, and test a range of sub-models. We identify a cross-classification of soil and land cover as providing the best spatial indicator of water quality of the classifications considered. The spatial model based on a selected grouped cross-classification was shown to account for between 35% and 90% of the spatial variability and the seasonal model accounted for between 45% and 100% of the temporal variability in the data. Analysis of residuals showed an inverse relationship between DOC and sulphate and between hydrogen ion concentration and calcium and magnesium. We also found residual correlations between sites which are strongly related to landscape class. These are attributed to landscape class by time interactions which are not accounted for in the simple multiplicative model.

Influence of food restriction coupled with weight cycling on carcass energy restoration during ad-libitum refeeding

Mature (450 g) rats were subjected to food restriction (60 percent of usual intake) with or without weight cycling (produced by cycles of 3 days of fasting followed by 7 days of refeeding). Weight cycling did not affect body weight, body composition, or food efficiency during the restriction period. However, the group subjected to weight cycling (WC) had an elevated level of lipoprotein lipase (LPL) activity in the epididymal adipose tissue as compared to the group receiving a constant amount of food each day (CO). After 40 days (four 10-day cycles) of food restriction, rats were allowed ad-libitum access to a stock diet for 18 days. WC rats restored carcass energy more rapidly, with a greater food efficiency than CO rats. Carcass energy was not totally restored at the end of the 18-day period, but WC rats had regained significantly more total carcass energy and total fat-free dry weight (FFDW) than CO rats. Food intake during refeeding did not differ significantly between WC and CO rats. These results suggest that weight cycling in a food-restricted program has the potential to increase food efficiency during a subsequent refeeding period.