Biomedical subjects
Publications and source records attributed to L Hess.
Although malpractice claims in pathology are relatively infrequent, the potential always exists. The author discusses some important areas in which pathologists could be held liable, and illustrates her points by citing some leading cases.
In previous work, we found that the phorbol ester drug 12-O-tetradecanoyl phorbol acetate (TPA) reverses the developmental restriction of melanogenesis that occurs early in neural crest development, causing Schwann cell precursors to undergo a metaplastic transformation into melanocytes. In this study, we examine whether these effects of TPA may be mediated by changes in endogenous levels of protein kinase C (PKC) activities. We report that low levels of PKC activity are correlated with this adventitious pigmentation in the crest-derived cells of dorsal root ganglia both during normal development and following TPA treatment in culture. These results suggest that regulation of endogenous levels of PKC plays a role in developmental decisions that neural crest cells make during early embryogenesis.
Nursing management of cardiac surgical patients has changed dramatically over the last several years. The need for cost-effective care with quality patient outcomes has forced critical care nurses to re-evaluate the standard of practice for postoperative cardiac patients. The authors describe the implementation of a fast-track weaning program giving critical care nurses more responsibility for weaning decisions and choice of sedative agent. Our experience in a six-bed Cardiothoracic Recovery Unit (CRU) in a midwestern community hospital evolved from receiving heavily anesthetized patients, continuing sedation postoperatively and prolonged intubation to minimal pharmacologic intervention with propofol and early extubation. In the fast-track weaning protocol, the nurses were given more authority to make critical decisions during the weaning process. This article describes the transition from the traditional time-based weaning system to the fast-track system where individual weaning progress is monitored by the critical care nurses.
Under conditions where cytochalasin B induces ATPase activity of monomeric actin (0.3 mM MgCl2, 1 mM EGTA, 30 microns cytochalasin B, 1 mM ATP) the rate constant of the exchange of actin-bound epsilon-ATP for free ATP is about 4-6 times faster than steady state ATPase activity. When a stoichiometric ATP-actin complex is extracted with PCA (single turnover experiment) the apparent rate constant of Pi generation is not faster than steady state ATPase activity. - The experiments suggest that the hydrolysis of actin-bound ATP and not the subsequent release of hydrolysis products is rate-limiting during cytochalasin-induced ATPase activity of actin.