ULTRASONIC REMOVAL OF EPILITHIC ALGAE IN A BAR-CLAMP SAMPLER1,2

A bar clamp with a collecting cup attached was used to collect epilithic algae samples on stones 4–50 cm diam.; stones were sampled by wading in shallow water and by SCUBA diving in deep water. The collecting cup delimits the sampling area (a 22 mm diam. circle) for cleaning and protects it from cell loss and desiccation. On some stones, ultrasonic vibration removed large numbers of cells (up to 62% of the total) missed by scraping and brushing.     

Analysis and prediction of antibacterial peptides

Background  

Antibacterial peptides are important components of the innate immune system, used by the host to protect itself from different types of pathogenic bacteria. Over the last few decades, the search for new drugs and drug targets has prompted an interest in these antibacterial peptides. We analyzed 486 antibacterial peptides, obtained from antimicrobial peptide database APD, in order to understand the preference of amino acid residues at specific positions in these peptides.     

Developments in microbiological risk assessment models for drinking water—a short review

Microbiological risk assessment (MRA) is the emerging method to predict the risks of infection from waterborne pathogens (e.g. rotavirus and Cryptosporidium parvum ) in the drinking water supply. The objectives of this paper are to review the appropriateness of current models, with emphasis on pathogen exposures through drinking water, and to consider the information necessary to further their development. Calculating pathogen exposures in MRA is currently limited by the fact that pathogen density data for drinking water supplies are only available for very large volume samples—much larger than imbibed daily by any consumer. To develop MRA, information is needed on how pathogens are dispersed within those large volumes at the resolution of volumes typically consumed daily by individuals. Available evidence suggests that micro-organisms, including pathogens, are clustered to some degree, even within small volumes, exposing some drinking water consumers to much higher doses than others. By assuming pathogens are randomly dispersed, current models overestimate the risk from the more infectious agents (e.g. rotaviruses) but underestimate the risk from less infectious pathogens (e.g. C. parvum ). Approaches to modelling pathogen densities in drinking water from source water data and treatment removal efficiencies require additional information on the degree to which treatment processes (e.g. filtration and coagulation) increase pathogen clustering. The missing information could be obtained from large-scale pilot plant studies.     

Transmission of the simian immunodeficiency virus SIVmne in macaques and baboons

A primate lymphotropic lentivirus was isolated on Hut 78 cells after cocultivation of a lymph node from a macaque that died with malignant lymphoma. In earlier studies SIV/Mne was inoculated into 17 macaques and two baboons. All of the macaques became viremic and seropositive. Fifteen of the macaques succumbed to a classic AIDS-like disease, whereas the baboons did not become viremic. The SIV/Mne virus has now been molecularly cloned and inoculated into Macaca nemestrina and baboons. A new transmission study has been initiated to test the effects of route and dosage on disease.