Hyperaemia in rat neocortex produced by acute exposure to methylenedioxymethamphetamine

Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [¹⁴C]iodoantipyrine and [¹⁴C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control.     

Normal pressure hydrocephalus.

Normal pressure hydrocephalus (NPH) is a neurological disorder characterized by a triad of symptoms: gait disturbance, dementia, and urinary incontinence. To date, the treatment of choice is cerebrospinal fluid diversion with a shunt. Because the clinical presentation of NPH mimics other neurological disorders, or can be perceived by healthcare providers as a natural aging process, it can be misdiagnosed or go undetected for many years. Patients with NPH suffer from debilitating physiological impairments as well as psychological disturbances. There are many different healthcare concerns in this population, including quality-of-life and safety issues. To achieve a more expedient diagnosis and treatment plan, nurses must be educated about this disorder.     

What has trust got to do with it? Cardiac risk reduction and family physicians' discussions of evidence-based recommendations

The management of patients through the use of evidence-based medicine has become the 'mantra' of medicine within many Western countries. Evidence-based medicine is aimed at providing the best objective, scientific care to all patients, and reducing as far as possible patients' risks of disease and complications from disease. Based on family physicians' discussions of the use of evidence-based recommendations for two cardiac diseases, this paper explores how subjectively-based trust enters into family physicians' decision to use evidence-based medicine. In addition, we show how trust influences physicians' work of recommending evidence-based medicine to patients, and physicians' perceptions of why patients follow recommendations aimed at risk reduction. We conclude that although much of the current discussion about evidence-based medicine assumes a 'rational' model of physician behaviour based on the application of the 'best objective scientific' results, subjectively-based perceptions of trust influence physician practices, and point to the need to understand the power of relational issues in influencing physician practices even when utilizing evidence-based knowledge.     

General practitioners'' views on continuing medical education.

BACKGROUND. The 1990 contract for general practitioners altered the provision of continuing medical education. AIM. This study set out to examine doctors' experiences of postgraduate education before and after the contract and their preferences for the provision of postgraduate education. METHOD. In 1991 a structured questionnaire was sent to 1959 doctors registered on the database held by the west of Scotland postgraduate office. RESULTS. An 82% response rate was obtained. Eighty eight questionnaires had to be excluded. Of 1523 respondents, 74% were entitled to study leave under the terms of their practice agreement, an increase of 15% since the introduction of the contract. When attending courses 11% reported that they always employed a locum (32% occasionally). Those who did so were more likely to be general practitioners in rural areas than in urban or mixed areas. Almost all respondents (1485, 98%) had participated in postgraduate education since April 1990. Lectures remained popular (47% of respondents indicated it was their preferred or most preferred choice) while distance learning and practice based learning were least preferred. Evening meetings and afternoon meetings were the most popular, and Wednesday and Thursday were reported to be the most suitable days for educational meetings. CONCLUSION. Organizing education for a large number of people is difficult, but individuals' preferences and difficulties have emerged which must be taken into account when doing so. In terms of attendance, postgraduate education seems to have been a success although its value in influencing quality of care is more doubtful. Perhaps the development of personal education plans may make learning more useful and relevant.     

Selections from current literature: treatment of hypertension.

The three papers reviewed for this issue deal with unrelated aspects of hypertension, illustrating the broad range of questions that still exist about optimal diagnosis and management. Physicians have for years been unsure about the efficacy, safety, and impact on morbidity of treating ISH. The result of these concerns has been that many, if not most patients with ISH never received treatment. The SHEP data are a powerful argument for routine treatment of ISH, which would represent a new standard of care for this condition. Only clinical experience and future trials will indicate whether treatment of ISH in the general population will be accompanied by the low incidence of side effects and morbidity observed in the more highly selected population of the SHEP trial. The study of Zeller et al. adds to the evidence that less is more, or at least the same, when it comes to treatment of hypertensive urgencies. The practice of oral 'loading' doses was not shown to improve therapeutic results. It is still not completely clear what criteria physicians should use in making a decision about inpatient parenteral therapy versus outpatient oral therapy. In patients with evidence of acute onset and end-organ injury, it is probably prudent to admit. In the absence of these risk factors, institution of an outpatient oral antihypertensive regimen can probably be accomplished with safety and at dramatically lower cost. The study of Koren et al. demonstrated a marked additional risk when LVH was present in hypertensive patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Distribution of transforming growth factor-beta 1 in human astrocytomas.

We used immunohistochemical techniques to study the distribution of transforming growth factor-beta 1 (TGF-beta 1) and infiltrating lymphocytes and macrophages in human astrocytomas. Thirteen of 15 grade 4 astrocytomas (glioblastomas) showed staining with anti-TGF-beta 1 antibody, predominantly in proliferating endothelial complexes and surrounding small and medium-sized blood vessels. Brain tissue microscopically free of tumor cells (n = 8) and more differentiated astrocytomas of varying grade (1 to 3; n = 6) devoid of endothelial proliferation did not stain with anti-TGF-beta 1. Normal brain contained only rare lymphoreticular cells. The majority of astrocytomas studied, however, contained T lymphocytes and macrophages with smaller numbers of B lymphocytes. The lymphoreticular infiltrates were concentrated primarily in close proximity to blood vessels. Within an individual tumor perivascular regions staining for TGF-beta 1 never contained more than occasional T lymphocytes. Perivascular regions not staining for TGF-beta 1 frequently contained low to high numbers of T lymphocytes. The inverse relationship in the distribution of TGF-beta 1 and lymphocyte infiltrates is compatible with a functional relationship between this cytokine and an immune effector cell response to glioblastomas.