Polyamines in Trichomonas vaginalis

Trichomonas vaginalis was grown in a modified Bushby's medium and putrescine, spermidine and spermine levels were determined in extracts from 24- and 48-h cultures and also in the culture media. All three polyamines were present in T. vaginalis extracts; the putrescine level and putrescine/spermidine ratio were much higher than those reported for other protozoa or for mammalian tissues. There were no significant differences between 24-h and 48-h amine levels per mg protein in these extracts, but amine levels per cell were higher at 24 than at 48 h. The spent culture media had a much higher putrescine content than corresponding uninoculated media and it was concluded that T. vaginalis secreted putrescine into the culture medium.     

How can the evaluation of genetic tests be enhanced? Lessons learned from the ACCE framework and evaluating genetic tests in the United Kingdom.

Advances in genetic technology are increasing the availability of genetic tests, not only for rare single gene disorders, but also for common diseases such as breast and colo-rectal cancer. Before there can be widespread uptake of these tests, they must be evaluated to confirm the benefits of their use. But how should genetic tests be evaluated, given the speed at which new tests are emerging? One highly influential approach is the analytic validity, clinical validity, clinical utility and ethical, legal and social issues (ACCE) framework, which has provided a benchmark for the evaluation of genetic tests. The approach has been adopted and adapted by the United Kingdom Genetic Testing Network, with the help of the Public Health Genetics Unit in Cambridge, to evaluate new genetic tests for use in the National Health Service. We discuss a number of conceptual, methodological, and practical issues concerning the evaluation of genetic tests, based on lessons learned from applying the ACCE framework and from the UK experience, and make a number of recommendations to further strengthen the evaluation of genetic tests.     

Heart rate, rate-pressure product, and oxygen uptake during four sexual activities

Heart rate, rate-pressure product, and VO2 were measured in ten healthy men during four specified sexual activities: coitus with husband on top, coitus with wife on top, noncoital stimulation of husband by wife, and self-stimulation by husband. Foreplay generated slight, but statistically significant, increases above resting baseline in cardiac and metabolic variables. From stimulation through orgasm, average effort was modest for relatively short spans. Maximum exercise values occurred during the brief spans of orgasm, then returned quickly to near baseline levels. The two noncoital activities required lower expenditures than the two coital positions, with man-on-top coitus rating the highest. Large variations among subjects and among activities discourage use of a general equivalent activity for comparison, such as "two flights of stairs," to represent "sexual activity."     

Conservering van cosmetica en contactlensvloeistoffen

Conclusie De verscheidenheid aan conserveermiddelen die in cosmetica worden toegepast, is zeer groot. Het is wenselijk het gebruik van deze verbindingen zo beperkt mogelijk te houden in verband met ongewenste bijwerkingen voor de gebruikers. Een effectieve conservering van produkten, waarin micro-organismen goed kunnen groeien, is echter noodzakelijk. Deskundige microbiologische begeleiding bij de ontwikkeling en fabricage van cosmetische produkten is dan ook essentieel.

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Voordracht gehouden tijdens het symposium Conserveermiddelen op 13 november 1980 te Rotterdam.

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Dit artikel wordt gelijktijdig geplaatst in De Waren Chemicus.     

The incidence of inherited metabolic disorders in the West Midlands, UK.

BACKGROUND: Inherited metabolic disorders (IMDs) are a heterogeneous group of genetic conditions mostly occurring in childhood. They are individually rare but collectively numerous, causing substantial morbidity and mortality. AIMS: To obtain up-to-date estimates of the birth prevalence of IMDs in an ethnically diverse British population and to compare these estimates with those of other published population-based studies. METHODS: Retrospective data from the West Midlands Regional Diagnostic Laboratory for Inherited Metabolic Disorders (Birmingham, UK) for the 5 years (1999-2003) were examined. The West Midlands population of 5.2 million is approximately 10% of the UK population. Approximately 11% of the population of the region is from black and ethnic minority groups compared with approximately 8% for the the UK. RESULTS: The overall birth prevalence was 1 in 784 live births (95% confidence interval (CI) 619 to 970), based on a total of 396 new cases. The most frequent diagnoses were mitochondrial disorders (1 in 4929; 95% CI 2776 to 8953), lysosomal storage disorders (1 in 5175; 95% CI 2874 to 9551), amino acid disorders excluding phenylketonuria (1 in 5354; 95% CI 2943 to 9990) and organic acid disorders (1 in 7962; 95% CI 3837 to 17 301). Most of the diagnoses (72%) were made by the age of 15 years and one-third by the age of 1 year. CONCLUSIONS: These results are similar to those of the comparison studies, although the overall birth prevalence is higher in this study. This is probably due to the effects of ethnicity and consanguinity and increasing ascertainment. This study provides useful epidemiological information for those planning and providing services for patients with IMDs, including newborn screening, in the UK and similar populations.     

Modification of MTT assay conditions to examine the cytotoxic effects of amitraz on the human lymphoblastoid cell line, WIL2NS

Reported parameters of the MTT assay vary widely, and reflect a need to optimise the assay for different cell types. The MTT assay conditions for the human B-lymphocyte-derived cell line WIL2NS were optimised for MTT incubation and formazan development. The optimised MTT assay was validated by examining the effects of the acaride amitraz on WIL2NS. In pH-buffered media in the absence of cells, MTT formed formazan spontaneously, and absorbance was proportional to both the initial concentration of MTT and the time of incubation at 37 °C. One milligram per millilitre MTT was toxic to WIL2NS cells, but the accuracy of the standard curve was reduced when only 0.2 mg/ml MTT was used. Twenty percent SDS in 0.2 M HCl was preferable to DMSO as a solvent for formazan. Exposure to 0.035% amitraz resulted in a significant reduction in WIL2NS cell numbers after only 2 h of exposure. It was concluded that 0.035% of amitraz has the potential to adversely affect lymphocytes in the systemic blood system in humans, and that an optimised MTT assay was obtained by incubating WIL2NS cells with 0.45 mg/ml MTT for 17 h, followed by addition of acidified SDS for 1 h.     

Transfer of oropharyngeal bacteria into the trachea during endotracheal intubation

Thirty-seven patients undergoing surgical operations were studied to detect transfer of oropharyngeal organisms into the trachea during endotracheal intubation. Nine of 27 patients with potentially pathogenic bacteria in the pharynx immediately before intubation were found to have these organisms, mainly Haemophilus influenzae, in the trachea at the end of operation. There was a trend for systemic antibiotic prophylaxis to reduce the persistence of bacteria in the trachea.