Activation of CPP32-like protease in tumor necrosis factor-induced apoptosis is dependent on mitochondrial function.

Mitochondria have been implicated in apoptosis, however, the precise mechanisms whereby mitochondria exert their effect are not clear. To gain further insights, we generated a panel of cells from ML-1a cells that were rendered respiration deficient by ethidium bromide treatment. Two respiration-deficient clones were subsequently reconstituted by fusion with platelets.

Single Dose Ofloxacin plus Loperamide Compared with Single Dose or Three Days of Ofloxacin in the Treatment of Traveler's Diarrhea.

Background: Although the use of the antimicrobial, trimethoprim-sulfamethoxazole, in combination with the antisecretory and antimotility agent, loperamide, has been shown to be efficacious in the treatment of traveler's diarrhea, the use of fluoroquinolone antimicrobials in combination with loperamide has less support in the literature. The present study was designed to compare the efficacy of ofloxacin versus ofloxacin plus loperamide in the treatment of acute traveler's diarrhea. Method: This prospective, randomized, evaluator-blinded treatment trial was conducted in Guadalajara, Mexico, during the summers of 1992-1994.

Interactions of oxytocin and vasopressin with CRF on the rat colon.

Corticotropin-releasing factor (CRF), a primary mediator of stress responses, produces changes in the gastrointestinal tract identical to those induced by stress. CRF is tenfold more potent in females than in males, but gonadectomy reverses this difference. We postulated that positive modulators of CRF, such as oxytocin (OT) and vasopressin (AVP), may act in females to potentiate effects of CRF and thus could account for the gender-related differences in colonic sensitivity to CRF and stress.

Morphine tolerance and dependence in the rat intestine in vivo.

There has been no previous demonstration of opioid tolerance and dependence with respect to the propulsive and contractile activities of the gut in vivo. In the experiments described herein, morphine was administered continuously (1 mg/kg/hr s.c.

An L-type calcium channel in renal epithelial cells.

A voltage-activated Ca++ channel has been identified in the apical membranes of cultured rabbit proximal tubule cells using the patch-clamp technique. With 105 mm CaCl2 solution in the pipette and 180 NaAsp in the bath, the channel had a conductance of 10.4 +/- 1.

Protection against Fas/APO-1- and tumor necrosis factor-mediated cell death by a novel protein, sentrin.

Fas/APO-1 and TNF receptor 1 share a common signaling motif in their cytoplasmic tail called the "death domain." Using the death domain as bait in the yeast two-hybrid system, several death domain-containing proteins that participate in cell death signaling have been identified. Here we report the isolation of a novel protein, sentrin, which interacts with Fas/APO-1 and TNF receptor 1 but not with FADD/MORT1 or CD40.

Teaching ethics in psychiatry : a problem-based learning approach.

During the last two decades, the teaching of ethics in the field of medicine, particularly in psychiatry, has become the subject of increased attention. For this type of training to be effective, it should be practical (as opposed to theoretical), focused on the decision-making process (as opposed to the rote learning of concepts), and, eventually, self-directed. This article suggests that a problem-based learning approach is an ideal method for reaching these goals.

Neuronal activity increases the phosphorylation of the transcription factor cAMP response element-binding protein (CREB) in rat hippocampus and cortex.

Activity-mediated gene expression is thought to play an important role in many forms of neuronal plasticities. We have used pentylenetetrazol-induced seizure that produces synchronous and sustained neuronal activity as a model to examine the mechanism(s) of gene activation. The transcription factor CREB (Ca2+/cAMP response element-binding protein) is thought to be necessary for long-term memory formation both in invertebrates and vertebrates.

Functional characterization of a non-AUUUA AU-rich element from the c-jun proto-oncogene mRNA: evidence for a novel class of AU-rich elements.

AU-rich RNA-destabilizing elements (AREs) found in the 3' untranslated regions of many labile mRNAs encoding proto-oncoproteins and cytokines generally contain (i) one or more copies of the AUUUA pentanucleotide and (ii) a high content of uridylate and sometimes also adenylate residues. Recently, we have identified a potent ARE from the 3' untranslated region of c-jun proto-oncogene mRNA that does not contain the AUUUA motif. In an attempt to further our understanding of the general principles underlying mechanisms by which AREs direct rapid and selective mRNA degradation, in this study we have characterized the functionally important structural features and properties of this non-AUUUA ARE.

What does the Beck Depression Inventory measure in chronic pain?: a reappraisal.

The Beck Depression Inventory (BDI) is widely used to document the prevalence of depression in suffers of chronic pain and in research designs about this population. Williams and Richardson (1993) initially posed the question, "What does the BDI measure in chronic pain?". Results from their study found 3 independent constructs, which differed somewhat from those obtained in analyses with other non-pain subsamples.

The ethics of learning and teaching medicine.

During the second half of the twentieth century, medicine turned its attention to the ethics of practice. A large and important literature has developed that clarifies the problems generated in the treatment of illness. The same focused attention now should be given to ethical issues and relationships connected with teaching and learning in medicine and to elaborating an ethics of education.