Advances in information technology. Implications for medical education.

Few kinds of technology have had as broad an impact on the recent affairs of humanity as have information technologies. The appearance and rapid spread in the past several years of innovations such as the Internet's World Wide Web and the emergence of computer networks connecting tens to hundreds of millions of people worldwide have occurred with startling rapidity. These global events portend substantial changes in the delivery of health care, the conduct of biomedical research, and the undergraduate, graduate, and continuing education of health professionals.

Apoptosis in rheumatoid arthritis: p53 overexpression in rheumatoid arthritis synovium.

DNA damage induces p53 tumor suppressor gene expression and protein production, which in turn facilitates DNA repair or apoptosis. Wild-type p53 protein has a short half-life, so it is rarely detected in non-neoplastic tissue. Because DNA fragmentation is abundant in the intimal lining in rheumatoid arthritis (RA) synovial tissue (ST) using in situ end-labeling (Firestein GS, Yeo M, Zvaifler NJ: Apoptosis in rheumatoid arthritis synovium.

Depression in late life. Diagnosis, course, and consequences.

Both major depression and dysthymia are common disorders in late life. However, making an accurate diagnosis may be more challenging than diagnosing depression in younger persons both because of comorbid general medical conditions and because of the illnesses, cognitive disturbances, and myriad adverse life experiences the elderly face. Often, dysphoria is sloughed off as an understandable response to adversity, and the diagnosis of depression is missed.

E2A gene products are not required for insulin gene expression.

Transcripts for E2A gene products, ubiquitous basic helix-loop-helix transactivating proteins, are expressed at high levels in the pancreatic epithelium. E2A proteins have been shown to bind the cognate E box sequence (CANNTG) of the insulin promoter/enhancer. E2A gene products dimerize with cell-specific basic helix-loop-helix proteins and synergize with the homeodomain transcription factor, PDX-1, in insulin gene transactivation.

Selective retrograde transport of nipecotic acid, a GABA analog, labels a subpopulation of gerbil olivocochlear neurons.

Perfusion of the gerbil cochlea with micromolar quantities of 3H-gamma-aminobutyric acid (GABA) results in rapid, selective labeling of 50-60% of the olivocochlear (OC) efferent terminals on afferent dendrites beneath the inner hair cells, and all of the efferent terminals beneath the outer hair cells. In order to identify the neurons from which these GABA-accumulating terminals originate, the cell bodies were localized by using retrograde transport of 3H-nipecotic acid, a metabolically inert GABA analog. With survival times of 6-30 hours after cochlear injection, myelinated OC efferent fibers and cell bodies were well labeled, with the greatest number being labeled at 12-18 hours.

Approaches to gene therapy of complex multigenic diseases: cancer as a model and implications for cardiovascular disease and diabetes.

The general concept of gene therapy is now well established and accepted by the medical, scientific and public policy communities, and is rapidly being implemented in human experimental studies. In addition to the initial models of single gene defects, target diseases have now come to include multigenic and multifactorial diseases such as human cancer, neurodegenerative diseases such as Parkinson's disease and firms of cardiovascular disease. While many conceptual and technical obstacles must still be overcome before therapy for disorders such as coronary artery disease and diabetes mellitus will easily be approached at the genetic level, the early results with several multigenic disease models gives some cause for optimism that gene therapies for even those complicated disorders will eventually become available.

Regenerative stimulus increases hepatocyte tight junctional permeability.

Experience with young animals, animals administered certain hepatotoxins and animals with two-thirds hepatectomy suggests that tight junctional permeability is increased in states characterized by architectural remodeling in the liver. In this work we correlate changes in tight junctional morphometry induced by two-thirds hepatectomy with changes in biliary permeability assessed by sucrose and horseradish peroxidase permeation and by alterations in biliary outputs of anionic and cationic cholephilic probes. By freeze-fracture examination tight junctional strand counts, density and orientation parallel to canaliculi were all reduced 24 hr after two-thirds hepatectomy.

Surgical repair of rhegmatogenous retinal detachment in immunosuppressed patients with cytomegalovirus retinitis.

The authors performed retinal reattachment surgery in 29 eyes of 24 patients with acquired immune deficiency syndrome virus with retinal detachment associated with cytomegalovirus (CMV) retinitis and documented the course of eight additional untreated eyes. Retinal detachment repair using vitrectomy, posterior hyaloid removal, and intraocular tamponade with silicone oil or SF-6 gas resulted in a total retinal reattachment rate of 76% and a macular attachment rate of 90% in one operation. The mean postoperative visual acuity (best corrected) was 20/60, but, in some patients, the visual acuity decreased because of progressive retinitis.

Management of the difficult adult airway. With special emphasis on awake tracheal intubation.

Difficulty in managing the airway is the single most important cause of major anesthesia-related morbidity and mortality. Successful management of a difficult airway begins with recognizing the potential problem. All patients should be examined for their ability to open their mouth widely and for the structures visible upon mouth opening, the size of the mandibular space, and ability to assume the sniff position.

Peritoneal dialysis for acute renal failure in children.

Fifty infants and children with acute renal failure were treated with acute peritoneal dialysis between 1987 and 1990. The patients were dialyzed using either a catheter introduced percutaneously over a guide-wire (n = 40) or a Tenckhoff catheter (n = 10). The cause of the acute renal failure was primary renal disease in 17 children, cardiac disease in 19, and trauma/sepsis in 14.

Leisure time exercise and lipid and lipoprotein levels in an older population.

Plasma lipid and lipoprotein levels were measured in 1,019 men and 1,273 women, aged 50 to 89, who were classified according to whether they reported participation in regular strenuous exercise. In men and women, strenuous exercisers had significantly (P less than .01) higher age-adjusted high-density lipoprotein (HDL) cholesterol levels than nonstrenuous exercisers, and male strenuous exercisers also had lower plasma triglyceride levels.

Resting electrocardiographic abnormalities suggestive of asymptomatic ischemic heart disease associated with non-insulin-dependent diabetes mellitus in a defined population.

The prevalence of ischemic heart disease (IHD) in older adults by glucose tolerance status was evaluated in 2,223 white men and women, aged 50-89 years, in the Rancho Bernardo cohort who were studied between 1984 and 1987. Impaired glucose tolerance (IGT) and non-insulin-dependent diabetes mellitus (NIDDM) were classified according to World Health Organization criteria. End points of ischemic heart disease were defined by Rose Questionnaire and resting electrocardiogram (ECG) according to the Minnesota Code.

Combined penetrating keratoplasty and vitreoretinal surgery with the Eckardt temporary keratoprosthesis.

The Eckardt style temporary keratoprosthesis was used in six cases of five eyes undergoing simultaneous penetrating keratoplasty and pars plana vitrectomy. This device provided excellent visualization of posterior and peripheral intraocular structures and maintained a closed system during surgery. Corneal grafts remained clear in 80% of the cases, and macular attachment was achieved with either silicone oil or perfluoropropane gas in 50% of cases followed for at least 6 months.

Role of the blood-nerve barrier in experimental nerve edema.

Nerve edema is a common response to the nerve injury seen in many peripheral neuropathies and is an important component of Wallerian degeneration. However, independent pathologic effects of nerve edema that aggravate or induce nerve injury extend the role of edema beyond that of an epiphenomenon of injury. New insights into the mechanism and impact of nerve edema come largely from animal models.

Activation of cell-specific expression of rat growth hormone and prolactin genes by a common transcription factor.

In the anterior pituitary gland, there are five phenotypically distinct cell types, including cells that produce either prolactin (lactotrophs) or growth hormone (somatotrophs). Multiple, related cis-active elements that exhibit synergistic interactions appear to be the critical determinants of the transcriptional activation of the rat prolactin and growth hormone genes. A common positive tissue-specific transcription factor, referred to as Pit-1, appears to bind to all the cell-specific elements in each gene and to be required for the activation of both the prolactin and growth hormone genes.

Are generic formulations equivalent to trade name topical glucocorticoids?

Trade name glucocorticoid formulations triamcinolone acetonide, fluocinolone acetonide, and betamethasone valerate were compared with their generic equivalents because of increasing substitution of generic formulations for trade name formulations. The vasoconstrictor assay was the method used for these comparisons. Large differences were found between generic and trade name formulations containing the same steroid in the same concentration in both cream and ointment vehicles.