Joaquin Maria Albarran Y Dominguez: Microbiologist, histologist, and urologist–a lifetime from orphan in Cuba to Nobel nominee

Joaquin Albarran was an extraordinary late 19th century urologist. His early career was in the field of microbiology and histopathology in Paris at a time of great medical developments and innovations. His later contributions to urology included the Albarran lever, Albarrans sign, Albarran-Ormond syndrome and seminal works on testicular and renal tumors. He also wrote treatizes on the pathophysiology of acute urinary retention, nephritis and calculus ureteric obstruction. He died at the young age of 52 from the effects of tuberculosis and in this same year was nominated for the Nobel prize in medicine.     

THE PITUITARY-LEYDIG CELL AXIS IN MEN WITH SEVERE DAMAGE TO THE GERMINAL EPITHELIUM

Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cardiac Electrophysiological Experiments in Numero, Part III: Simulation of Arrhythmias and Pacing

This paper is the third and final part of a series of articles reviewing mathematical and computer models of the electrophysiological processes. This section reviews the arrhythmia simulation and discusses models of arrhythmogenic processes, fibrillation and defibrillation, and of heart-pacemaker interaction. The models of arrhythmogenesis are classified into three main sections: models of reentry and vortex reentry, models of myocardial electrotonic interactions, and models of macroreentrant supraventricular tachycardias. This final part of the review discusses the future potential of mathematical and computer models of different cardiac processes.     

Telemetry of Programmed and Measured Data in Pacing System Evaluation and Follow-up

Telemetry of programmed and measured data is an important feature of many pacemakers currently used in clinical practice. The ability to receive non-invasive data from the implanted device constitutes a major advantage for the long-term follow-up of the patients and of device performance. There are numerous types of data retrievable via telemetry: parameters of device characteristics (output, battery longevity, impedance, etc), event recorders or counters, event markers, and endocardial electrograms. Ideally, this information should be beneficial in the longitudinal surveilance of modern pacemakers.     

Agminate Spitz naevi arising on hyperpigmented patches

In 1948 Dr Sophie Spitz described criteria that distinguished juvenile melanoma from malignant melanoma.¹ Since then the cases of eruptive Spitz naevi have been reported arising on normal skin, on lightly pigmented patches and on hypopigmented patches. There are only 12 reports of Spitz naevi arising on hyperpigmented patches:^2-12 we describe here three further cases, all on the arms of children, seen in our department in a single year.     

The Effect of 50 Hz External Electrical Interference on Implanted Cardiac Pacemakers

The effects of injected 50 Hz alternating current on the function of cardiac pacemakers has been observed in 18 patients with implanted unipolar VVI units. Current, in the range 0-600 microA was applied via electrodes attached to the patients' upper body and feet and fed from a specially designed current injection unit at the bedside. Most implanted pacemakers reverted to interference mode in the current range 29-250 microA. At current levels just below the reversion current all units developed irregular and inappropriate pacing. This current level was pacemaker dependent and varied in the range 27-246 microA. The total reversion current depended on the location of the injecting electrodes and on the patients' posture. The sensitivity of the units to injected interference was increased by deep inspiration. Temporary pacing catheters fitted to an additional ten patients were used to monitor the interference voltage which would be sensed by an implanted unit. This voltage was similarly dependent on patient posture and on deep respiration. Current injection has proved to be a safe, controllable and reproducible method of testing the sensitivity of implanted pacemakers to 50 Hz external interference.