Permanent Transvenous Pacing After a Mustard Procedure

HANDLER, C.E., ET AL.: Permanent Transvenous Pacing After a Mustard Procedure. We report the case of a 20-year-old man born with transposition of the great arteries who underwent emergency balloon septostomy and subsequently a Mustard procedure. When aged 20 years, he had several syncopal attacks due to sinoatrial disease for which he was simply and successfully paced transvenously in VVI mode.     

In-vivo Monitoring of Dosage Forms*

The use of imaging techniques including gamma scintigraphy to follow the behaviour of drug formulations has revolutionized our knowledge of absorption and distribution in drug delivery. The development of gamma camera techniques as physiological tools to explore organ function became routine by the mid-seventies. Several research groups started to explore the applications of technique in drug delivery. Within 5 years, the utility of the technique became obvious and scintigraphy is now widely accepted as an important investigation tool in formulation research. Gamma scintigraphy is especially useful in exploring sources of inter-subject variation, especially in examining food effects in pharmacokinetic estimations and establishing windows of absorption for oral delivery. As a tool to examine drug delivery to the lung and to the eye, scintigraphy is the method of choice. Magnetic Resonance Imaging (MRI) became more generally employed in medicine two decades after the gamma camera. The superior soft-tissue contrast and resolution compared to computed X-ray tomography rapidly established MRI in clinical investigation. Recent applications in oral drug research has allowed the pharmaceutical scientist to explore new facets of delivery and ultimately combine MRI and scintigraphy in human clinical trials.     

Characterization of Surfactant Effect on Aggregates in Model Aerosol Propellent Suspensions

A novel technique of rheometry combined with image analysis to study model aerosol suspensions used in inhalation technology has been used. The role of surfactants in the stability and aggregation of such suspensions was also investigated. Addition of increasing concentrations of sorbitan monooleate (Span 80) to suspensions of micronized polar solids in model CFC suspensions caused marked changes in aggregate morphology and suspension stability. The aggregate behaviour was characterized in a modified constant stress rheometer by use of image analysis techniques, allowing the measurement of particle size, elongation and fractal dimension as a function of shear stress. This method was used to study the effect of Span 80 on suspensions of lactose and salbutamol sulphate in P113. Lactose suspensions showed a gradual reduction in aggregate size, and more spherical structure, with increasing surfactant concentration. Salbutamol sulphate suspensions displayed a more prominent transition from an aggregated state to a weakly aggregated state at 0.02% w/w surfactant. Both suspensions were disaggregated by shear, the resulting fractal properties of the aggregates in shear demonstrating the increased particle mobility caused by the surfactant.     

Switch movements and the myosin crossbridge stroke

The myosin II motor from Dictyostelium discoideum has been engineered to contain single tryptophan residues at strategic locations to probe movements of switch 1 and switch 2. The tryptophan residue at W501 probes movement of the relay helix and indirectly reports on switch 2 movement. This probe suggests that there is an equilibrium between the switch 2 open- and closed-states when the γ-phosphate position is occupied. Actin does not appear to greatly affect this equilibrium directly, but has indirect influence via switch 1. The latter region has been probed by introducing tryptophan residues at positions 239 and 242. The kinetics of the actomyosin ATPase in solution is discussed with respect to recent crossbridge models based on high-resolution crystal structures. To whom correspondence should be addressed: Tel.: +44-(0)-116-229-7048; Fax: +44-(0)-116-229-7018; E-mail: crb5@le.ac.uk     

Community-based sale, distribution and insecticide impregnation of mosquito nets in Bagamoyo District, Tanzania

When insecticide-impregnated mosquito nets are used in malariacontrol programmes, distribution, promotion of usage and impregnationwith insecticide are typically the responsibility of the personnelof the programme. In order to create a more sustainable systemfor implementing bed net interventions, a bed net committeewas formed in each of 13 villages in the study area. Implementationis proceeding by stages in 4 groups of 3–4 villages eachto allow committee members and project personnel to identifyproblems and solve them before implementation starts in thenext area. Once nominated and confirmed in a village meeting,committee members attend a day-long seminar in which they discusshow distribution, sales of nets and impregnation should takeplace. Committee members not only help on ‘distributiondays’, but also promote proper usage of the nets and assistvillagers who have difficulties setting up the nets. A revolvingfund is being established for each village to pay committeemembers and purchase nets and insecticide after the projectends. Factors which may affect the sustainability of this systemare discussed.     

Death and survival in a cohort of heroin addicts from London clinics: a 22-year follow-up study

Data are presented on the 43 people who died over a 22-year follow-up period of a cohort of 128 heroin addicts drawn in 1969 from the newly opened London clinics. The main causes of death were drug-related, with 18 deaths specifically determined as due to overdose, of which the great majority were among people being prescribed opiates at the lime. The mortality rate was a mean of 1.84% annually, and the excess mortality ratio was 11.9. This excess was highest at the beginning and varied over the period of study, appearing higher at the opening of the clinics and again in the mid-1980s. No sex differences in mortality rates were demonstrated but the excess mortality wan concentrated at younger ages. No prediction of the 85 survivors could be made on the basis of length of heroin use prior to study intake, nor on age at intake.