Three-dimensional structure of bradykinin in SDS micelles

The conformational properties of bradykinin in five molar excess sodium dodecyl sulfate (SDS) micelles have been examined by two-dimensional nuclear magnetic resonance (NMR) techniques at 500 MHz. Detailed structural information for bradykinin in SDS was obtained from quantitative 2-D nuclear Over-hauser enhancement (n.O.e.) analyses, distance geometry, and restrained molecular mechanics and dynamics calculations. The conformation of bradykinin in SDS micelles, as determined by these methods, is characterized by a β-turn-like structure at residues 6–9. A detailed comparison of the structures derived from distance geometry and restrained molecular mechanics and dynamics is also presented.     

How many hysterectomies should purchasers buy?

In the reorganized British National Health Service (NHS), purchasersare supposed to assess the health care requirements of theirresident populations and contract for an appropriate volumeof services. In the case of elective surgical procedures thiscan be problematic when there is no reliable information onhealth needs and no consensus on appropriate rates of use. Anexamination of hysterectomy rates in 8 districts in 1 RegionalHealth Authority found a nearly 2-fold variation in population-basedrates, a difference which had persisted for at least 12 years.A detailed comparison of a high- and a low-rate district wasconducted to assess the extent to which the variations in therates were related to indices of data quality, resource availability,use of alternative surgical procedures, use of private hospitals,differences in gynaecologists' admission thresholds and differencesin demand. The difference was not accounted for by supply factors,but there were significant differences between the 2 districtsin levels of demand for specialist gynaecology services anddifferences in gynaecologists' admission thresholds. It seemslikely that the low-rate district contained a greater numberof general practitioners who were willing to treat patientsthemselves rather than refer them to specialists. Because ofthe sparsity of scientific evidence on which to base judgementsabout appropriateness and the lack of consensus about need,it will be impossible to specify a target figure for an optimalhysterectomy rate.     

Biobehavioral research on nicotine use in women

More American women are taking up smoking than men and fewer are quitting; if current trends continue, rates for women will surpass those for men by the mid-1990's. But ironically, much of what is known about the biobehavioural aspects of smoking is based on research using male subjects. The present paper reviews evidence suggesting that: (1) women may differ from men with regard to nicotine intake and/or effects; (2) nicotine intake and effects may be influenced by menstrual cycle phase; (3) oral contraceptive use and estrogen replacement therapy may affect intake and effects of nicotine; (4) the effects of chronic nicotine use on female reproductive endocrinology may have implications for the reinforcement of smoking; and (5) pharmacological agents used to treat smoking may have different effects in women than in men. Guidelines and suggestions are presented by future biobehavioural research in women, including standardization of assessment procedures, attention to the use of appropriate controls, and use of pharmacological probes.     

Symptomatic dermographism: wealing, mast cells and histamine are decreased in the skin following long-term application of a potent topical corticosteroid

Clobetasol propionate 0.05% ointment and an otherwise identical steroid-free base were applied topically to a 10 cm2 area on the anterior thighs of six patients with symptomatic dermographism for 6 weeks. Four patients showed a significantly decreased wealing response to stroking of steroid pretreated skin compared to that of control sites. There was a parallel decrease in mast cell numbers and histamine levels in skin biopsies taken from the steroid treated areas. At 6 weeks two patients demonstrated a decrease in flare areas following the intradermal injection of compound 48/80 in steroid pretreated skin compared to base treated sites. Flare areas following intradermal injection of histamine in these two patients were equivalent in base and steroid treated skin.     

The families of problem drug users: a study of 50 close relatives

The research described in this paper resulted from a-collaborative multi-centre study of the relatives of problem drug users involving six practitioners and researchers, in four centres within the south-west of England. The objective of this research was simply to interview 50 close relatives of identified problem drug users, with the identification occurring through clinics and self-help groups. Quantitative and qualitative results show that large numbers of these relatives reported many negative experiences. The partners of illicit drug users reported both more and differently patterned problematic behaviours than those of prescribed tranquilliser users. The partners of illicit users also reported different problems to those of the parents. Relatives reported many negative effects in terms of how they viewed the drug user, and how the experiences had affected their health. They also described various coping mechanisms, and the extent of the support which they had received. The results are discussed in terms of coping, and similarity with research into the families of problem drinkers.     

Color stability of three composite resins used in the inlay/onlay technique

Abstract – The color stability of three composite resins used in the inlay/onlay technique was determined by means of irradiation with UV-light and by water storage. Generally, water storage resulted in greater changes in color than did UV-light, but no correlation was found between the results of the two chromogenic procedures. The microfilled composite resin was the least color stable material, but none of the resins had alarmingly low color stability.     

DEEP CORNEAL STROMAL OPACITIES WITH CONTACT LENSES

Two patients with deep corneal stromal opacities occurring after prolonged contact lens wear are described. The opacities were associated with folds or striae in Descemet's membrane which they overlay. Development of the opacities was associated with ocular discomfort, photophobia, reduced vision and a history of prolonged daily wearing times. Although the corneal endothelial cell counts were within the normal range, the count was reduced in the affected eye in the patient with the unilateral deep stromal opacity and there was mild polymegathism of the endothelial cells. It is possible that the long-term effects of subtle endothelial cell changes may cause a keratopathy with later scarring and opacification. Poor oxygen trans-missibility, carbon dioxide build-up, or suction effects by the lens may all be aetiological factors. Early recognition and treatment, particularly with a better fitting lens of high oxygen transmissibility is important, as once developed the opacities regress only slowly and may result in permanent visual impairment.