Estimation of serum gentamicin by quenching fluoroimmunoassay

A new type of non-isotopic immunoassay, applied to the determination of serum gentamicin, is reported. The method is based on partial quenching of fluorescence observed when fluorescein-labelled gentamicin is bound by anti-gentamicin serum. The fluorescence intensity of the labelled gentamicin in an unseparated immunoassay incubation mixture therefore serves to indicate the extent of binding, which is related to the amount of competing unlabelled gentamicin present. Precision and accuracy are shown to be similar to those of the best existing methods for gentamicin, while the new assay is more rapid and technically simpler, and avoids the use of expensive radio-chemicals with their attendant health hazard. Assays of patient samples correlate with established bioassay and polarisation fluoroimmunoassay methods.     

Influence of probenecid and spironolactone on furosemide kinetics and dynamics in man

The pharmacokinetics and pharmacodynamics following administration of furosemide (40 mg intravenously) have been studied before and after treatment with probenecid (0.5 gm orally every 6 hr for 3 days) and spironolactone (200-mg initial oral dose followed by 50 mg every 6 hr for 3 days) in 6 normal male subjects. Urine losses during each study period were replaced with saline-dextrose-KCl intravenously. The study was performed with the use of a Latin-square design. Probenecid pretreatment induced significant reductions in renal clearance of furosemide by 78%, the extrarenal clearance by 56%, and the volume of distribution by 52%. As a consequence, furosemide half-life was increased by 54%. Probenecid significantly reduced the rate of sodium excretion at all plasma concentrations of furosemide, but the ratio between urinary furosemide concentration and urinary sodium concentration was not altered. Since the proportion of furosemide excreted unchanged in the urine was not markedly changed, total diuretic response was not influenced by probenecid. There was no evidence of any pharmacokinetic interaction between spironolactone and furosemide. The relationship of furosemide kinetics to dynamics observed in these studies confirms that, in man, the diuretic response is determined by drug that reaches the renal tubule rather than the drug level in plasma.     

Antimicrobial prophylaxis for catheter-associated bacteriuria

We evaluated short-term systemic antimicrobial prophylaxis for catheter-associated bacteriuria in women undergoing elective gynecological operations in a prospective, controlled, double-masked study. Nine of 100 placebo-treated patients acquired bacteriuria during catheterization compared with 3 of 96 of the drug-treated group. However, at the time of hospital discharge, clean-voided urine specimens were positive as frequently in the drug-treated group (8 of 82 patients cultured) as in the placebo group (8 of 75 patients cultured). No difference in febrile morbidity due to bacteriuria was noted between the prophylaxis and placebo groups. The incidence of catheter-associated bacteriuria may be reduced by antimicrobial prophylaxis. However, because the protective effect is transient and is associated with the selection of resistant organisms, prophylaxis is not indicated for patients at low risk for acquired bacteriuria and in whom the sequelae of catheter-associated infections are infrequent.     

Studies on the neurophysiology of the vas deferens

In order to investigate the mechanism of sperm transport along the genital ducts, intraluminal pressure of isolated segments of the vas deferens was recorded in vivo. Responses to filling and mechanical as well as pharmacologic and electric stimulation of the autonomic nervous system were monitored. Contraction waves were initated in response to the stretch of filling and from mechanical stimulation. Pharmacologic response was variable. Low doses of alpha-adrenergic stimulant produced an increase in frequency of the contraction wave. Large doses of the same drug induced stroking contraction of the entire vas. alpha-Blocking drugs did not alter the rhythmic activity of the vas. beta-Adrenergic stimulation blocked peristaltic activity while administration of parasympathomimetic drugs increased the force of contraction. Electric stimulation of the hypogastric nerve produced strong sustained contractions. These data suggest that, whenever stretched, the vas deferens responds by regular peristaltic waves of low amplitude. These peristaltic waves can be enhanced by sympathomimetics or electric stimulation of the sympathetic system. The contents of the vas are propulsed into the urethra through strong rhythmic contractions of the entire vas.     

Entwicklung rechtssicherer Web-Anwendungen

A broad variety of juridical requirements has to be considered during the development of Web-applications. Disregard of these requirements holds severe financial dangers. A complete compilation of juridical requirements is complicated due to the multitude of juridical areas and the variety of Web-applications. Therefore, a development-driven juridical framework is suggested. From a software engineering point of view it is crucial to capture requirements at an early stage of development in order to avoid much higher costs at a later time. Thus, specialized conceptual modelling methods are examined with regard to their capability to model juridical requirements. A lack of methodical support is identified which is addressed by a systematic adaption and extension of the eW3DT method.     

Management of allergic bronchopulmonary aspergillosis without maintenance oral corticosteroids: a fifteen-year follow-up

Five non-smoking patients were diagnosed as having allergic bronchopulmonary aspergillosis in 1978/9. All have been treated since then with inhaled corticosteroids, using short courses of self-administered oral corticosteroids for symptomatic exacerbations. Over a mean 15 years of follow-up, they have required on average less than one course of oral drugs per annum. Regular monitoring of spirometry has shown no evidence of deterioration, and all have close to normal gas transfer. All have some localized bronchiectasis on CT scanning, in two cases probably occurring after treatment started, but in no case is there any respiratory disability. We conclude that this is a safe and effective method for the management of allergic bronchopulmonary aspergillosis when diagnosed before persistent hyphal colonization of the airways has occurred.