High resolution solid-state 29si nmr spectroscopy of silicone gels used to fill breast prostheses

We have used ²⁹Si solid-state nuclear magnetic resonance (NMR) spectroscopy to study the chemical structure of the silicone gels in virgin and explanted breast prostheses. Despite evidences of alteration in the morphological appearance of the silicone gel inside the breast prosthesis, our results do not reveal changes in the chemical nature and structure of the silicone gels after implantation. In addition to the main ²⁹Si resonance peak at ?22.26 ppm that corresponds to the resonance frequency of the D repeat unit of the polysiloxane chains, the high sensitivity of our NMR technique allows the detection of very low concentrations of silicone compounds. Within our experimental detection limit of 0.2%, no signal between ?90 ppm and ?150 ppm are observed. This indicates that no silica products are present inside the gel of the prostheses. Furthermore, our ²⁹Si NMR spectra indicate differences in the chemical compositions of the silicone gels from different manufacturers.     

Health of a team competing in the 1990 World Solar Car Challenge.

The health of a team participating in the 1990 World Solar Car Challenge was recorded for 10 of the 11 race days. Morbidity was collected during daily consultations with the team doctor and the diagnoses were later converted to the ICPC code. Team members' self-perceived health status was also recorded daily, using the Nottingham Health Profile. Team drivers consulted the doctor more often than the support staff and the three full-time drivers had significantly more diagnoses than the support staff. The Nottingham Health Profile scores on sleep, energy and emotional reactions showed correlations between higher minimum temperatures and sleep for all team members and for the three full-time drivers, there were significant correlations between increasing maximum temperatures and emotional reaction scores. The morbidity records and perceived health scores reflect the conditions of the race. Twenty-five per cent of full-time driver consultations dealt with skin, eyelid or finger infections probably caused by the lack of washing water. The scores on sleep and emotional reactions were affected by temperature and previous research reports degradation in concentration and dual tasks with increasing temperature. This may account for the difficulty some drivers had in continuing their shifts. Close supervision of the drivers and the recording of their perceived health status helped reduce the health problems of the team.     

Binge drinking: prevalence, patterns and policy

This paper presents analyses of the pattern of ‘bingedrinking’ in Wales, based on data drawn from a 1993 surveyof 12 167 (67%) 18–64 year olds resident in 15 212 householdsin Wales. Binge drinking, defined as drinking half the weeklyrecommended units of alcohol in a single drinking session, wasfound to be most prevalent among young adults, males, the manualsocial group, those who did not undertake any further educationafter secondary school, those who are single, divorced or separated,beer drinkers and those who concentrate most of their drinkingat weekends. 28.2% of men and 8.2% of women reported binge drinkingat least once a week, of whom about 42% felt that their levelof drinking was harmful to their health. About a quarter statedthat they would like to reduce their alcohol consumption butonly a small number had been advised to do so by their GeneralPractitioner. The public health impact of binge drinking isdiscussed. It is recommended that sensible drinking messagesshould emphasize the need to reduce binge drinking as well asto moderate overall weekly consumption and should be supportedby policies to create environments that support sensible alcoholuse.     

Serotonin 5- HT (2C) receptor knockout mice: autoradiographic analysis of multiple serotonin receptors.

Quantitative receptor autoradiography was used to study possible alterations of the densities of multiple serotonin (5-HT) receptor subtypes and of serotonin transporter in the brain of 5-HT(2C) receptor knockout mice. The radioligands employed were [(3)H]citalopram, [(3)H]WAY100,635, [(3)H]8-OH-DPAT, [(3)H]GR125743, [(3)H]sumatriptan, [(3)H]MDL100,907, [(125)I](+/-)DOI, [(3)H]mesulergine, [(3)H]5-HT, [(3)H]GR113808, and [(3)H]5-CT. As expected, radioligands that label 5-HT(2C) receptors showed a complete absence of labeling in mutant mice choroid plexus and significantly reduced densities in other brain regions expressing 5-HT(2C) receptors. With the rest of the radioligands, no significant alterations in the densities of labeled sites were found in any brain region. In situ hybridization showed no changes in 5-HT(2A) receptor and serotonin transporter mRNA levels, whereas 5-HT(2C) receptor mRNA levels were reduced in certain brain regions. The present results indicate that the mouse serotonergic system does not exhibit compensatory up- or down-regulation of the majority of its components (serotonin transporter and most 5-HT receptor subtypes) in response to the absence of 5-HT(2C) receptors.