Making a home in the community for the academic medical center.

Academic medical centers (AMCs) have traditionally provided primary care for low-income and other underserved populations. However, they have had difficulty developing lasting partnerships with other organizations serving the same populations. This article describes an exception to the rule, in which an academic division was created at Duke University Medical Center to develop effective collaborations with health care and social service providers in Durham, North Carolina, including both public agencies and private organizations. Together, the division and its partners have created and operate programs that improve health outcomes and access to care for those at risk. These programs share a number of characteristics: they are designed to meet the needs of the patient, not the provider; they are based in the community, not in the AMC; they bring services to people's homes, schools, and neighborhoods; they are multidisciplinary, combining health, social, and even mental health services; and, once established, they are revenue-generating and can be made self-supporting when grant funding ends. These programs are also innovative. They are designed to model and test new ways of organizing and delivering care. Preliminary indications suggest that they also strengthen the AMC's relationships with the surrounding community.     

Promoting clinically effective practice: general practitioners' awareness of sources of research evidence

BACKGROUND: Practitioners are being encouraged to base their clinical practice on research evidence. In order to do this, they must be aware of and use the sources of evidence. METHODS: A questionnaire survey was undertaken to establish GPs' awareness of research evidence in their clinical practice and, in fundholding practices, its influence on purchasing plans. Questionnaires were sent to 360 lead fundholders in North Thames Region and 440 of a random sample of the remaining general practitioners in the region for comparison. RESULTS: Questionnaires were returned by 62% of lead fundholders and 63% of GPs in the random sample. There was limited use of the electronic sources of clinical effectiveness. There was greater reported awareness of published sources of research evidence and fundholding GPs were significantly more likely to have referred to publications summarizing research evidence. CONCLUSIONS: GPs seem to make more use of published clinical effectiveness sources than the electronic databases. Consequently, they need educational and technical support if they are to make full use of the available sources of research evidence available in other media.      

Neointimal hyperplasia in balloon-injured rat carotid arteries: the influence of hyperhomocysteinemia.

PURPOSE: Hyperhomocyst(e)inemia (hH[e]) is a risk factor for atherosclerosis. Neointimal hyperplasia (NH) after vessel injury can contribute to atherosclerosis. In this study, we investigated the effects of hH(e) on NH formation after arterial balloon injury in rats. METHODS: Lewis rats that were given a hH(e)-inducing (high methionine, low folate) or normal diet for 150 days underwent common carotid artery (CCA) balloon injury. Two and 4 weeks after injury, CCAs were formalin perfusion-fixed, sectioned, and stained for elastin. Neointimal index (NI, percent lumen occlusion) and neointima (N) and media (M) area were measured by using computer-interfaced microscopy. RESULTS: Plasma homocyst(e)ine (H[e]) levels were elevated in rats given the study diet compared with rats given the normal diet at days 40 and 90 (69 +/- 8 and 73 +/- 9 micromol/L vs 4 +/- 0.4 and 4 +/- 0.6 micromol/L, P <.001). After balloon injury, the CCA NI and N/M ratio, but not the M area, were increased by hH(e) compared with normal plasma H(e) (2 weeks [n = 6,7]: NI = 7.3 +/- 1.7 vs 2.9 +/- 0.7, P =.002, and N/M = 0.31 +/- 0.08 vs 0.08 +/- 0.02, P <.001; 4 weeks [n = 4,7]: NI = 13.1 +/- 2.2 vs 6.3 +/- 1.3, P =.002, and N/M = 0.36 +/- 0.08 vs 0.17 +/- 0.03, P <.001). CONCLUSION: hH(e) accelerates NH in a rat CCA balloon-injury model. The effect of hH(e) on NH may contribute to increased atherosclerosis in humans with hH(e).     

Death of a classified worker probably caused by overexposure to gamma radiation.

This paper describes the case of an industrial radiographer who was seriously overexposed to gamma radiation. The exact circumstances of this exposure were not established but it was concluded that he was repeatedly irradiated probably to a total average whole body dose of at least 10 Gy over several years. Also, a much larger dose to a hand required its partial amputation. He developed myelodysplasia, which progressed to acute myeloid leukaemia from which he died. Karyotypic examination of the leukaemic blasts showed changes very similar to those associated with secondary leukaemia that may develop after radio or chemotherapy. The paper describes his medical case history, the investigation of his workplace, and the attempts to estimate his radiation dose by chromosomal analysis of blood lymphocytes and electron spin resonance of dental enamel and bone.     

Actions of growth factors on plasma calcium. Epidermal growth factor and human transforming growth factor-alpha cause elevation of plasma calcium in mice.

Specific humoral substances produced and secreted by human tumors that cause hypercalcemia have not been identified. Certain growth factors (such as epidermal growth factor, platelet-derived growth factor, and transforming growth factors-alpha and -beta) have been shown to stimulate the resorption of bone in organ culture by both prostaglandin-dependent and prostaglandin-independent pathways. In this report we demonstrate that epidermal growth factor and recombinant human transforming growth factor-alpha induce a significant rise in plasma calcium concentration when administered repeatedly to intact mice for periods ranging from 24 h to 16 d. The elevation of plasma calcium is not dependent on dietary calcium and is not invariably accompanied by an increase in systemic levels of the prostaglandin E2 metabolite 13,14-dihydro-15-keto-prostaglandin E2. The in vivo calcium-mobilizing activity of epidermal growth factor and transforming growth factor-alpha indicate that these or related growth factors need be considered as potential mediators of tumor-induced hypercalcemia.     

The effect of dialysate on peritoneal phagocyte oxidative metabolism

The respiratory and oxidative responses of human peritoneal polymorphonuclear leukocytes (PMN) and peritoneal macrophages (PM phi) following exposure to unused continuous ambulatory peritoneal dialysis fluid (CAPD) and early dwell effluent were studied using an open oxygen (O2) electrode system and by measurement of oxygen radical-derived luminol-dependent chemiluminescence. Both cell types responded to stimulation by increasing O2 consumption and by generating chemiluminescence even at external O2 concentrations below 50 microM O2. Oxygen concentrations in the dialysate, as measured by blood gas analysis, were never lower than 118 +/- 8.3 microM O2 even during active peritonitis. Thus oxygen availability does not appear to be rate limiting for phagocyte oxidative metabolism in the peritoneal cavity. Preexposure of both inflammatory cell types to unused fluid or early dwell CAPD effluent significantly reduced both stimulated oxygen uptake and the subsequent ability of these cells to generate chemiluminescence without significantly affecting their viability. Further investigation of this down regulatory phenomenon using unused fluid and laboratory prepared dialysis fluid revealed that low pH (5.3) and high sodium lactate concentration in combination are directly responsible for the suppressive effect of unused fluid and early dwell effluent on cell function. These observations demonstrate that cellular host defense may be impaired early in the dialysis cycle as a result of lactate mediated "stunning" of resident phagocytes. The precise nature of the molecular species responsible for this suppressive effect remains to be identified.