Both human and newborn rabbit lens epithelial cells exhibit similar limited growth properties in tissue culture.

Human lens cells from 5-91-year old individuals were cultured in 8 different basal media containing fetal bovine, adult bovine, rabbit or human serum or human plasma or in a serum-containing medium supplemented with insulin, epidermal growth factor, fibroblast growth factor plus other hormones or trace elements. Cultures were initiated from explants of the capsule and epithelium or following enzymatic dissociation of cells from the capsule. Under all conditions the epithelial cells had a limited doubling potential. As a function of time in culture, cells enlarged, displayed numerous filaments and exhibited apparent in vitro senescence. Lens epithelia from 4-6 day old rabbits cultured under identical conditions mimicked the behavior of human lens cells. Lens epithelia from newborn rabbits may be a suitable model for investigating the basis of apparent in vitro senescence in this cell type and could help in defining the conditions required for the long-term growth of human lens cells. The limited growth of human lens epithelia suggests that these cells require tissue-specific nutrients or hormonal supplements not present in standard tissue culture media.

Catastrophic thrombus development despite systemic heparinization during coronary angioplasty: possible relationship to nonionic contrast.

Two cases of catastrophic thrombus formation during coronary angioplasty occurred shortly after the operators began using nonionic contrast. This occurred despite systemic heparinization, the adequacy of which was documented by activated clotting times (ACT). Both cases were resistant to balloon inflation and one was refractory to intracoronary thrombolysis. There is a considerable body of evidence documenting that low-osmolality contrast media, especially those that are nonionic, have less anticoagulant effect than standard contrast media. Several reports have also been published suggesting possible relationships between nonionic contrast and intravascular thrombus formation during coronary angiography and angioplasty. These data are reviewed and recommendations made for utilization of these contrast media.

Transseptal catheterization in adults: enhanced efficacy and safety by low-volume operators using a "non-standard" technique.

Transseptal catheterization is often not performed because of concerns about morbidity and mortality. The authors present several refinements of this technique that have allowed a series of cases to be done with minimal morbidity or mortality. This was possible despite limited previous experience in this technique and a relatively low-volume of cases.

Dorsal bunions: a review.

The authors present a review of the literature on dorsal bunion and describe its classification, etiology, predisposing factors, and different methods of treatment. The deformity is functionally limiting during ambulation and cosmetically undesirable for the patient. It is a progressively disabling deformity that requires surgical management.

Retention of lens specificity in long-term cultures of diploid rabbit lens epithelial cells.

Rabbit lens epithelial cells from newborn animals exhibited limited growth when cultured under standard conditions. Cell lines were generated when explants from individual lenses were cultured in medium supplemented with conditioned medium or untreated rabbit serum. All lines exhibited a stable epithelial morphology. One line, N/N1003A, was examined extensively with respect to its growth, ploidy, and maintenance of lens-specific functions. Cells at population-doubling level (pdl) 120 exhibited a normal chromosomal banding pattern, were diploid, were non-tumorigenic in vivo, did not grow in suspension culture, and did not exhibit sustained growth in medium supplemented with low concentrations of serum. The shape of the growth curves and the final density for cells at pdl 24 and 181 exposed to various concentrations of serum were identical. The cells showed no diminution in growth as a function of in vitro age. The cells retained lens-specific functions. Proteins were isolated from cells at pdl 40 and 170, and were separated on polyacrylamide gels. Western immunoblot analysis using antiserum to alpha-crystallin, a tissue-specific protein found in lens epithelial cells in vivo, indicated the presence of alpha-A- and alpha-B-crystallin polypeptides. The cells also contained the transcription factors required for activating the murine alpha-A-crystallin gene promoter, which is known to function with precise tissue specificity. When an expression vector including the bacterial chloramphenicol acetyltransferase (CAT) gene controlled by the alpha-A-crystallin gene promoter was introduced into the lens epithelial cells, the CAT gene was expressed.(ABSTRACT TRUNCATED AT 250 WORDS)

Bleeding complications in the uremic patient.

Many patients seen in podiatric medicine may have some degree of renal disease. An often neglected and unrecognized complication of renal disease may be abnormal bleeding. Presented in this paper is a review of the etiologies and treatment of uremia-induced bleeding complications. Included is a case presentation in which the authors discuss a patient in acute renal failure who developed postoperative bleeding following an incision and drainage for a diabetic foot infection.