Synergistic effect of iontophoresis and a series of fatty acids on LHRH permeability through porcine skin

This study examined physiological response to an encounter with and touch by an unfamiliar person. Fifty-five African American (23 male, 30 female) and 51 European American (23 male, 28 female) undergraduates participated. A Black or White interactor entered the room, introduced himself or herself, checked equipment for 30 s, and then took a pulse for 30 s. Entry of the interactor resulted in increased corrugator and zygomaticus facial muscle activity (EMG), increased skin conductance (SC), and heart rate (HR) acceleration. Corrugator EMG was greater among Black subjects; White subjects responded with more zygomatic EMG and SC and greater HR acceleration. Women showed a more positive facial expression than did men. Being touched reduced EMG and HR but resulted in increased SC. White and Black males showed more HR acceleration when encountering a Black male interactor.     

Two-dimensional pattern analysis and classification using a complexorthogonal estimation algorithm

An orthogonal estimation algorithm is derived for the estimation of parameters associated with the complex autoregressive boundary model of two-dimensional shapes. It is shown that the coefficients of the orthogonal model and the original system parameters are invariant to rotation around the origin, to the choice of starting point in tracing the boundary and to scale and translation. The error reduction ratios derived from the estimation algorithm can be used to detect which terms should be included in the system model, and classification based on the orthogonal parameters is shown to be less susceptible to incorrect model order specification. Classification based on orthogonal data sets is also derived, and it is demonstrated that this approach can avoid some problems associated with classification based on the model parameters alone     

Kinetic isotope effects in methane coupling on a reducible oxide catalyst

Kinetic isotope effects in methane activation on a reducible Na/MnO_x/SiO₂ catalyst have been investigated. The results show that there is a kinetic isotope effect for the formation of C₂ products but not for the formation of CO_x, products. These observations conflict with kinetic measurements of the rate of formation of C₂ products which appear to show that the reaction is second order with respect to the methane partial pressure. It is concluded that the rate determining step is activation of the C-H (or C-D) bond and that the apparent second order kinetics is an artefact of the kinetic analysis. The absence of a kinetic isotope effect in the formation of carbon oxides is discussed.     

Promoting smoking cessation among cancer patients: a behavioral model

The smoking cessation clinical practice guideline recently published by the Agency for Health Care Policy and Research (AHCPR) summarizes current knowledge on smoking cessation treatments. Among its recommendations, the guideline encourages physicians to motivate patients who indicate that they are not yet ready to quit smoking. Because medical training typically emphasizes pharmacologic rather than behavioral treatment, we believe that physicians caring for cancer patients may benefit from more extensive instruction in motivating patients to quit smoking. This article describes how a contemporary theoretical approach, the transtheoretical model of change, can be used to promote behavioral change. Multiple studies, primarily in the field of smoking cessation, provide strong empiric support for use of this model in clinical practice. The model consists of five stages of smoking cessation that describe different levels of readiness to quit: precontemplation, contemplation, preparation, action, and maintenance. A diagnostic tool is presented, and specific smoking cessation counseling strategies are suggested for each stage of change. Implications for the use of the model by physicians who counsel and treat smokers are discussed.     

Immortalization of osteoclast precursors by targeting Bcl -XL and Simian virus 40 large T antigen to the osteoclast lineage in transgenic mice

Cellular and molecular characterization of osteoclasts (OCL) has been extremely difficult since OCL are rare cells, and are difficult to isolate in large numbers. We used the tartrate-resistant acid phosphatase promoter to target the bcl-XL and/or Simian Virus 40 large T antigen (Tag) genes to cells in the OCL lineage in transgenic mice as a means of immortalizing OCL precursors. Immunocytochemical studies confirmed that we had targeted Bcl-XL and/or Tag to OCL, and transformed and mitotic OCL were readily apparent in bones from both Tag and bcl-XL/Tag mice. OCL formation in primary bone marrow cultures from bcl-XL, Tag, or bcl-XL/Tag mice was twofold greater compared with that of nontransgenic littermates. Bone marrow cells from bcl-XL/Tag mice, but not from singly transgenic bcl-XL or Tag mice, have survived in continuous culture for more than a year. These cells form high numbers of bone-resorbing OCL when cultured using standard conditions for inducing OCL formation, with approximately 50% of the mononuclear cells incorporated into OCL. The OCL that form express calcitonin receptors and contract in response to calcitonin. Studies examining the proliferative capacity and the resistance of OCL precursors from these transgenic mice to apoptosis demonstrated that the increased numbers of OCL precursors in marrow from bcl-XL/Tag mice was due to their increased survival rather than an increased proliferative capacity compared with Tag, bcl-XL, or normal mice. Histomorphometric studies of bones from bcl-XL/Tag mice also confirmed that there were increased numbers of OCL precursors (TRAP + mononuclear cells) present in vivo. These data demonstrate that by targeting both bcl-XL and Tag to cells in the OCL lineage, we have immortalized OCL precursors that form bone-resorbing OCL with an efficiency that is 300-500 times greater than that of normal marrow.     

Angioscopic predictors of early adverse outcome after coronary angioplasty in patients with unstable angina and non-Q-wave myocardial infarction

BACKGROUND: Clinical and angiographic criteria have a limited ability to predict adverse outcome in patients with unstable angina who are undergoing percutaneous transluminal coronary angioplasty (PTCA). We investigated whether the use of angioscopy can improve prediction of early adverse outcome after PTCA. METHODS AND RESULTS: Angioscopic characterization of the culprit lesion was performed before PTCA in 32 patients with unstable angina and 10 with non-Q-wave infarction. Seven patients (17%) had an adverse outcome (myocardial infarction, repeat PTCA, or need for coronary artery bypass graft surgery) within 24 hours after PTCA. Six of 18 patients with a yellow culprit lesion had an adverse outcome compared with 1 of 24 in whom the culprit lesion was white (P = .03). Six of 20 patients with plaque disruption suffered an adverse outcome compared with 1 of 22 with nondisrupted plaques (P = .04). Six of 17 patients with intraluminal thrombus had an adverse outcome, whereas only 1 of 25 patients without thrombus suffered an adverse outcome (P = .01). Yellow color, disruption, and thrombus at the culprit lesion site were associated with an eightfold increase in risk of adverse outcome after PTCA. The prediction of PTCA outcome based on characteristics of the plaque that were identifiable by angioscopy was superior to that estimated by the use of angiographic variables. CONCLUSIONS: In patients with unstable angina and non-Q-wave infarction, angioscopic features of disruption, yellow color, or thrombus at the culprit lesion site can identify patients at high risk of early adverse outcome after PTCA. Angioscopy was superior to angiography for prediction of PTCA outcome.