Didactic value of the clinical evaluation exercise. Missed opportunities

BACKGROUND: Primary cholesteatoma of the temporal bone is a very rare disease. Initially, the tympanic membrane is intact, and often facial palsy may be the presenting symptom. The authors present a case of primary cholesteatoma which was surgically treated using a transmastoid-translabyrinthine approach. Other surgical approaches to the petrous apex are discussed.     

Transport properties are not altered across Caco-2 cells with heightened TEER despite underlying physiological and ultrastructural changes

Selected properties of Caco-2 cells were examined after disparate transepithelial electrical resistance (TEER) measurements were observed in two populations of Caco-2 cells. Comparisons were made between the early passages of Caco-2 cells (Caco-2E, passages 35-47) and the later passages of cells (Caco-2L, passages 87-112). Transmission electron microscopy revealed that regions of Caco-2L cells were composed of multiple cell layers rather than the monolayers observed in Caco-2E cells. Epithelial cell height (or barrier thickness) was not significantly different between the two cell populations. Intercellular and intracellular lumina were observed in the Caco-2L cells, but not in the Caco-2E cells. Results of [3H]thymidine incorporation assays showed significantly higher cell proliferation rates in Caco-2L cells relative to Caco-2E cells. Despite morphological and physiological changes, there were no significant differences in the apparent permeabilities for D-mannitol (paracellular diffusion marker), hydrocortisone (transcellular diffusion marker), or dipeptide, Gly-Sar (carrier-mediated transcellular transport marker) between the two populations of cells. The higher TEER values in Caco-2L cells may be the results of a slight perturbation of tight junctions associated with both the multiple cell layers and the presence of intercellular lumina.     

Current trends in endodontic treatment: report of a national survey

The authors surveyed 360 general dentists and 291 endodontists to obtain information on routine, nonemergency endodontic treatments adapted to clinical practice. Frequent practices and recent advances in treatment modalities-including instrumentation, obturation, intracanal preparations, medications and restorations-are highlighted.     

The effects of pre-exercise starch ingestion on endurance performance

This study compared the physiological responses and performance following the ingestion of a waxy starch (WS), resistant starch (RS), glucose (GL) and an artificially-sweetened placebo (PL) ingested prior to exercise. Ten college-age, male competitive cyclists completed four experimental protocols consisting of a 30 min isokinetic, self-paced performance ride preceded by 90 min of constant load cycling at 66% VO2max. Thirty min prior to exercise, they ingested 1 g.kg-1 body weight of GL, WS, RS, or PL At rest, GL elicited greater (p < 0.05) serum glucose and insulin responses than all other trials. During exercise, however, serum glucose, insulin, blood C-peptide and glucagon responses were similar among trials. The mean total carbohydrate oxidation rates (CHOox) were higher (p < 0.05) during the GL, WS, and RS trials (2.59 +/- 0.13, 2.49 +/- 0.10, and 2.71 +/- 0.15 g.min-1, respectively) compared to PL (2.35 +/- 0.12 g.min-1). Subjects were able to complete more work (p < 0.05) during the performance ride when they ingested GL (434 +/- 25.2 kj) or WS (428 +/- 22.5 kj) compared to PL (403 +/- 35.1 kj). They also tended to produce more work with RS ingestion (418 +/- 31.4 kj), although this did not reach statistical significance (p < 0.09). These results indicate that preexercise CHO ingestion in the form of starch or glucose maintained higher rates of total carbohydrate oxidation during exercise and provided an ergogenic benefit during self-paced cycling.     

Cost-effectiveness of case management: experiences of a university managed health care organization

Primary seborrhoea was diagnosed in 14 English springer spaniels over a 17-year period. Seven of the dogs developed clinical signs by two years of age. The dermatosis began as a generalised non-pruritic dry scaling which gradually worsened. Some dogs remained in this dry (seborrhoea sicca) stage, but in most cases the dermatosis became greasy and inflamed (seborrhoea oleosa and seborrhoeic dermatitis). Eight of the dogs suffered from recurrent episodes of superficial or deep bacterial pyoderma. Histological findings in skin biopsy specimens included marked orthokeratotic hyperkeratosis of surface and infundibular epithelium, papillomatosis, parakeratotic capping of the papillae, and superficial perivascular dermatitis in which lymphocytes and mast cells were prominent. The dogs with seborrhoea sicca responded more satisfactorily to therapy with topical emollient-humectant agents or oral omega-3/omega-6 fatty acid supplementation. Dogs with seborrhoea oleosa and seborrhoeic dermatitis did not respond satisfactorily to topical therapy. One dog, however, responded well to etretinate and omega-3/omega-6 fatty acid administration. No dog was cured.     

Pharmacokinetic interpretation of data gathered during therapeutic drug monitoring

We review some pharmacokinetic principles that can facilitate interpretation of data obtained during therapeutic drug monitoring: the one- and two-compartment models, volume of drug distribution, drug clearance, organ clearance, bioavailability, first-pass effect, chronic or repetitive dosing, and use of urine and saliva to measure drug clearance and drug binding to plasma proteins, respectively. We also describe use of saliva to estimate rapidly, conveniently, and noninvasively the concentration of the free, pharmacologically active form of the drug as well as the fraction of drug bound to plasma protein.