Characterisation of angiotensin converting enzyme from different rat vascular beds

To gain further insight into the operation of 5-HT autoreceptor-mediated feedback control of 5-HT biosynthesis in serotonergic nerve terminal areas, the effect of the 5-HT1B and the 5-HT1A receptor agonists, TFMPP and 8-OH-DPAT, respectively, were investigated in the rat central nervous system (CNS) using in vivo and in vitro neurochemical approaches. TFMPP suppressed 5-HT synthesis (5-HTP accumulation after decarboxylase inhibition) both in vivo and in vitro. In vivo, the 5-HT synthesis-suppressing effect of the drug (3.0 mg/kg, s.c.) proved resistant to either acute hemitransection or reserpine (5 mg/kg, i.p.; 90 min before) pretreatment. In vitro, in cortical, hippocampal and striatal slice preparations, TFMPP (0.1-10 microM) decreased 5-HT synthesis under basal and stimulated (30 mM K+) conditions, an effect which was unaltered by prior in vivo reserpine-induced 5-HT depletion but was attenuated in the presence of 5-HT1B receptor antagonists such as methiothepin, cyanopindolol or propranolol. The 8-OH-DPAT (0.1 mg/kg, s.c.)-induced decrease of 5-HT synthesis in vivo was abolished by hemitransection but resistant to acute reserpine pretreatment; 8-OH-DPAT (10 microM) did not decrease 5-HT synthesis in vitro. In conclusion, the present study confirms the importance of 5-HT autoreceptors in the feedback control of nerve terminal 5-HT biosynthesis. Specifically, our data indicate: (1) that the reduction of rat brain 5-HT synthesis after TFMPP is mediated by 5-HT1B autoreceptors located on the serotonergic axon terminals, and (2) that the effect is directly mediated and occurs independently of 5-HT neuronal firing and intact monoamine stores.     

Josamycin and rosamicin: in vitro comparisons with erythromycin and clindamycin

The macrolide antibiotics josamycin and rosamicin were compared in vitro with erythromycin for activity against Staphylococcus aureus, S. epidermidis, and enterococci and with clindamycin for activity against a variety of anaerobic organisms. Rosamicin and erythromycin were similar in activity and superior to josamycin against aerobic cocci. Most isolates of S. aureus (96%), S. epidermidis (79%), and the enterococci (87%) were inhibited by 1.56 mug of either of the new macrolide compounds per ml. Clindamycin was the most active compound against the anaerobic organisms.     

Tyrosine-derived polycarbonate membrane in treating mandibular bone defects. An experimental study.

This study was designed to evaluate the suitability of a novel bioabsorbable material in treating bone defects. A poly(desaminotyrosyl-tyrosine-ethyl ester carbonate) (PDTE carbonate) membrane (thickness 0.2-0.3 mm) was implanted into the mandibular angle of 20 New Zealand White rabbits to cover a through-and-through defect (12 x 6 mm). In group 1, the defects were left unfilled but covered with membrane and in group 2 the defects were filled with bioactive glass mesh and covered with membrane, too. Controls were left uncovered and unfilled. The animals were followed for 6, 12, 24 and 52 weeks, respectively. The material was evaluated by qualitative analysis of histological reactions and newly formed bone.We found that PDTE carbonate elicited a modest foreign body reaction in the tissues, which was uniform throughout the study. New bone formation was seen in all samples after six weeks. Group 1 had more new bone formation until 24 weeks and after this the difference settled. Based on findings of this study it was concluded that PDTE carbonate membranes have good biocompatibility and are sufficient to enhance bone growth without additional supportive matrix.     

Prospective predictors of body dissatisfaction in adolescent girls and boys: A five-year longitudinal study.

This study investigated prospective risk factors for increases in body dissatisfaction in adolescent girls and boys in the Eating Among Teens Project. At the time of first assessment (Time 1), participants were a cohort of early adolescent girls (N=440) and boys (N=366) and a cohort of middle adolescent girls (N=946) and boys (N=764). Participants were followed up 5 years later (Time 2). Potential prospective risk factors examined included body mass index, socioeconomic status, ethnicity, parent dieting environment, peer environment, and psychological factors. Predictors of Time 2 body dissatisfaction were Time 1 body dissatisfaction, body mass index, socioeconomic status, being African American, friend dieting and teasing, self-esteem, and depression. However, the profile of predictors differed across the samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

From quantum mechanics to physical metallurgy of steels

Abstract

In the last decade there has been a breakthrough in the construction of theories leading to models for the simulation of atomic scale processes in steel. In this paper the theory is described and developed and used to demonstrate calculations of the diffusivity and trapping of hydrogen in iron and the structures of carbon vacancy complexes in steel.     

Swelling of polyelectrolyte hydrogels using a finite element model

In this work, a modular finite element model is proposed to describe the swelling of a poly(acrylic acid) hydrogel for optical applications under the influence of an electric field. The module divides the problem into five parts, depending on the specific energy domain involved. This includes electrical, chemical, force, mechanical and optical components. Each part is then solved sequentially to provide the final result. Initial predictions for the deformation are acceptable, and suggest that only a certain amount of energy may be available to deform the hydrogel during the swelling process.     

Historical account of the contributions of E. C. Bain

This paper attempts to summarize some of Edgar Bain’s inspired contributions to metallurgy during a period of about a decade—surely one of the most intensely creative eras in the history of the profession. It is necessarily subjective and to some extent incomplete, but it hopefully provides a documentation of clear thinking about important practical and theoretical problems and of incisive experimentation to confirm critical hypotheses. H. W. PAXTON, on leave from Carnegie-Mellon University, Pittsburgh, Pa., is Director, Division of Materials Research, National Science Foundation, Washington, D.C.