Alzheimer's disease.

Alzheimer's disease, the commonest cause of dementia, is a growing global health concern with huge implications for individuals and society. In this review, current understanding of the epidemiology, genetics, pathology and pathogenesis of Alzheimer's disease is outlined, before its clinical presentation and current treatment strategies are discussed. Finally, the review discusses how our enhanced understanding of Alzheimer pathogenesis, including the recognition of a protracted preclinical phase, is informing new therapeutic strategies with the aim of moving from treatment to prevention.

Manipulations of sensory information: a test of the hypothesis of redundancy of knowledge of results.

The hypothesis of redundancy in knowledge of results was examined by manipulating the amount and location of sensory information available to participants performing a coincident anticipation timing task. Either the last 8 lights or the last 16 lights of the visual display were visible to 48 participants. Following an acquisition phase, learning was tested over immediate (5-min.) and delayed (24-hr.) retention intervals. The main finding was that performance was better when knowledge of results was present, regardless of the amount of sensory information available; therefore, knowledge of results was not redundant information for learning this task.

Innovative low-risk maternity clinic. Family physicians provide care in Calgary.

PROBLEM BEING ADDRESSED: Because some family physicians choose to stop providing maternity care, many women and their physicians have to seek this care from other providers. These providers must respect family physicians' relationships with patients and the necessity of returning the family to the referring physician for primary care after appropriate maternity and newborn care has been provided. OBJECTIVE OF PROGRAM: To design a clinic to address this problem and to deal with the practical issues, such as preservation of lifestyle, adequate remuneration, and avoiding litigation, family physicians face when they choose to practise obstetrics. To provide role models and training opportunities for future family physicians. MAIN COMPONENTS OF PROGRAM: Compatibility and cooperation among member physicians is essential in order to provide care to a substantial number of patients using an established protocol. A well-organized call schedule allows clinic physicians to enjoy a reasonable lifestyle. CONCLUSIONS: The clinic, established and organized by family physicians, provides family-centred maternity care for women and their families when their family physicians choose not to practise obstetrics.

Decreased vasopressin content in parvocellular CRH neurosecretory system of Lewis rats.

Rats possess stress-responsive, vasopressin (VP)-expressing and stress-nonresponsive, VP-deficient subpopulations of parvocellular corticotropin-releasing hormone (CRH) neurosecretory cells. Both subpopulations are activated by bacterial lipopolysaccharide (LPS) and cytokines. Lewis rats exhibit hyporesponsive hypothalamo-pituitary-adrenocortical axes (HPAAs). The Lewis CRH neurosecretory system has been reported to be defective in females and normal in males. We used post-embedding electron microscopic (EM) immunocytochemistry to study baseline levels and LPS-stimulated depletion of neurosecretory vesicles. Male Lewis rats possessed normal numbers of CRH+/VP- varicosities and low numbers of CRH+/VP+ varicosities, indicating abnormally low release of VP into portal blood. This defect contrasts with the reported increase in VP content and release in magnocellular neurosecretory cells in Lewis rats.

L-glutamine: an amino acid required for maintenance of the tegumental membrane potential of Schistosoma mansoni.

The tegumental membrane potential (-63 +/- 2.9 mV) of adult male Schistosoma mansoni in RPMI-1640 is significantly depolarized (-26 +/- 7.3 mV) when the parasite is incubated in inorganic media (Hank's Balanced Saline or RPMI-1640 without organic constituents). Of 9 amino acids (L-glutamine, D-glutamine, L-arginine, L-proline, L-aspartate, L-glutamate, L-asparagine, L-isoleucine and L-methionine) L-glutamine alone is sufficient to repolarize the membrane potential to a value (-56 +/- 4.5 mV) not significantly different from that found in RPMI-1640. Repolarization by glutamine is dose-dependent, with significant effects obtained as low as 0.10 mM. The concentration of phosphate in the medium also significantly alters the membrane potential. Physiological levels of phosphate (5.6 mM) are necessary in conjunction with L-glutamine to obtain the full repolarization of the membrane potential. In the absence of organic constituents, the membrane potential is strongly dependent on the external medium pH. When L-glutamine is present in the medium, the membrane potential becomes virtually independent of the external pH.