Psychological,situational, and gender predictors of cardiovascular reactivity to stress: A multivariate approach

This study examined whether relationships between anger expression, hostility, social evaluative anxiety, and a presumed mechanism for coronary heart disease development, cardiovascular reactivity (CVR) to stress, are moderated by stress situation and gender and whether such relationships are attenuated by inadequate assessments. Subjects (47 men, 47 women) were assigned randomly to either a Harassment or a Social Evaluation condition, under which they performed a reaction time task. SBP, DBP, and HR measures were recorded during baseline and task. Multiple regression analyses indicated that expressed anger was related to CVR only among men in the Harassment condition; that hostile men who express anger showed the most CVR across situations, and that the traits assessed here did not predict CVR among women. Results suggest that assessments of coronary-risk and interventions to reduce risk may need to take into account attitudes, styles of emotional expression, environmental factors, and gender.This research was supported in part by an NIMH predoctoral fellowship (F31MH09836) awarded to John W. Burns and by a grant from the American Heart Association (89-01-3G) awarded to Edward S. Katkin.     

Lymphatic drainage from the skin of the back to retroperitoneal and paravertebral lymph nodes in melanoma patients

Background: Preoperative lymphoscintigraphy (LS) with^99mTc antimony sulphide colloid is now part of the routine management of patients with intermediate thickness melanoma at the Sydney Melanoma Unit. Over a 13-year period, 1375 patients have been examined using LS, and we have observed many unusual lymphatic drainage pathways, including direct drainage through the body wall to retroperitoneal and paravertebral lymph nodes from the skin of the back. The aim of this study was to determine the incidence of such drainage in the 542 patients who had primary melanoma sites on the posterior trunk. Methods: The lymphoscintigrams performed on these patients were examined for the presence of direct lymphatic drainage through the posterior body wall to sentinel nodes in the retroperitoneal and paravertebral regions. Results: Lymphatic drainage directly through the body wall to such lymph nodes occurred in 14 of these 542 patients. Conclusions: Preoperative knowledge of the presence of this lymph drainage pattern may influence surgical management, and follow-up investigations in these patients can be tailored to ensure that the relevant areas are examined with anatomic imaging or F18-FDG PET scans.     

Ruminative Response Style and Vulnerability to Episodes of Dysphoria: Gender, Neuroticism, and Episode Duration

A number of recent laboratory and prospectivefield studies suggest that the tendency to ruminateabout dysphoric moods is associated with more severe andpersistent negative emotional experiences (e.g., Morrow & Nolen-Hoeksema, 1990;Nolen-Hoeksema & Morrow, 1991). The current paperreports two studies that tested the hypotheses that (a)ruminative response styles act as a trait vulnerabilityto dysphoria, particularly to relativelypersistent episodes of dysphoria; (b) aspects ofrumination that are not likely to be contaminated withthe presence and severity of previous symptomatology(introspection/self-isolation, self-blame) demonstrate vulnerability effects;and (c) rumination mediates the effects of gender andneuroticism on vulnerability to dysphoria. Consistentsupport was found for each of these hypotheses. Overall, our data suggest that rumination mightreflect an important cognitive manifestation ofneuroticism that increases vulnerability to episodes ofpersistent dysphoria.     

Corticosteroids for the Enhancement of Fetal Lung Maturity: Impact on the Gravida with Preeclampsia and the HELLP Syndrome

Summary: This study was undertaken to determine maternal impact of corticosteroids administered for the promotion of fetal lung maturity in mothers with the HELLP syndrome. Twenty-seven of 427 women with the HELLP syndrome treated between 1980–1991 received a full course of steroids prior to preterm delivery. This group was compared to 27 matched control patients with the HELLP syndrome who received no corticosteroids. Subjects were matched for maternal age, race, sex of the fetus, and severity of the HELLP syndrome. The antepartum platelet count stabilized or increased in 25 of 27 steroid-treated women in contrast to 0 of 15 control women (p <0.00001). In comparison to control patients, LDH serum concentrations in steroid-treated patients stabilized or decreased and the SGOT/AST and SGPT/ALT stabilized or decreased during therapy (p < 0.005). The interval from delivery to platelet nadir in patients with Class III HELLP syndrome was shorter in the steroid-treated group (p<0.008) than in untreated patients.     

Quantification of tissue plasma volume in the rat by contrast-enhanced magnetic resonance imaging

Magnetic resonance imaging enhanced with a macromolecular contrast medium (MMCM), albumin-Gd-DTPA, was used to estimate the plasma volume in vivo in the myocardium, lung, liver, and skeletal muscle of 10 normal rats. The plasma volumes of the same tissues in a parallel group of six rats were estimated in vitro by a conventional radioisotopic technique (¹¹¹In-transferrin). Plasma volumes of myocardium, lung, liver, and skeletal muscle estimated by the MR technique (μl plas. ia cc-¹ of tissue) were 101,109,163, and 11.0, respectively, while plasma volumes measured by the In-transferrin radioisotope technique (mg plasma g-¹ of tissue) were 78.6, 215,143, and 11-2, respectively. Assuming a ratio of densities of aerated lung to blood of 0.45 and of other tissues to blood of 1.0, correlation between the methods was excellent (R² = 0.99) indicating that MR imaging enhanced with MMCM permits reliable in vivo estimation of tissue plasma volume in the rat.     

The potential of topoisomerase I inhibitors in the treatment of CNS malignancies: report of a synergistic effect between topotecan and radiation

Summary Despite innovations in imaging, surgery, and radiation therapy, local failure remains the principle clinical problem in most CNS malignancies. To date, chemotherapy has not made a major impact in the treatment of most adult CNS tumors. The inroads made by chemotherapy in pediatric CNS malignancies suggest that novel drugs, or drug combinations, may improve therapy. Topoisomerase I (Topo I) inhibitors are a relatively new group of chemotherapy drugs with a novel mechanism of action. Drugs in this group currently undergoing clinical trials are the Camptothecin analogues Topotecan, CPT-11, and 9-aminocamptothecin. There is substantial preclinical and some clinical evidence to suggest that these drugs could be useful in the treatment of CNS malignancies. Preclinical studies with the water soluble Topo I inhibitor, Topotecan, demonstrate antineoplastic activity in a variety of CNS malignancies. In addition, Topotecan has good CNS penetration in primates, and recent preliminary phase I and II clinical trials of Topotecan in pediatric and adult CNS malignancies have been promising. In this paper, we describe the unique mechanism of action, antineoplastic activity, and radiosensitizing properties of Topo I inhibitors. We present the first report demonstrating potentiation of radiation lethality by Topotecan in a human glioma (1354) cell line. The dose enhancement ratio was 3.2 at 10% survival. Thus, there is evidence to suggest that Topo I inhibitors may be beneficial in the treatment of CNS neoplasms on the basis of their antineoplastic activity alone, as well as their radiosensitizing effects. Two clinical trials which utilize concurrent Topotecan and radiation in the treatment of pediatric and adult CNS malignancies are discussed.     

Inhibition of ligand binding to g protein-coupled receptors by arachidonic acid

Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects of AA on ligand binding to the mAChR subtypes (M₁, M₂, M₃, M₄, and M₅) and to the μ-opioid receptor, β₂-adrenergic receptor (β₂-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding to all mAChR subtypes, to the β₂-AR, the 5-HTR, and to the μ-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3–25 μM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by which AA inhibits GPCR function.     

Living related liver transplantation. Progress or regress?

The impetus for the devolopment of living related liver programmes lies with donor shortage, which relates inversely to the success of generating cadaveric donors. A shrinking or non-existent cadaveric donor pool leads to an increased death rate among potential recipients awaiting transplantation. The living related liver programmes have by and large been successful, though it is accepted that there is potentially a significant risk to the donors. The technique of live donor liver transplantation is clearly here to stay, but the selection of suitable donors is between the family and the unit. Consequently, because of the lack of international guidelines, the programmes are open to abuse. Steps should be taken to establish either mechanisms of control or a worldwide register to combat this potential.