The Economic Impact of Pig-Associated Parasitic Zoonosis in Northern Lao PDR

The parasitic zoonoses human cysticercosis (Taenia solium), taeniasis (other Taenia species) and trichinellosis (Trichinella species) are endemic in the Lao People’s Democratic Republic (Lao PDR). This study was designed to quantify the economic burden pig-associated zoonotic disease pose in Lao PDR. In particular, the analysis included estimation of the losses in the pork industry as well as losses due to human illness and lost productivity. A Markov-probability based decision-tree model was chosen to form the basis of the calculations to estimate the economic and public health impacts of taeniasis, trichinellosis and cysticercosis. Two different decision trees were run simultaneously on the model’s human cohort. A third decision tree simulated the potential impacts on pig production. The human capital method was used to estimate productivity loss. The results found varied significantly depending on the rate of hospitalisation due to neurocysticerosis. This study is the first systematic estimate of the economic impact of pig-associated zoonotic diseases in Lao PDR that demonstrates the significance of the diseases in that country.     

Factors influencing the biosorption of gadolinium by micro-organisms and its mobilisation from sand

The present work was devoted to the study of the biosorption capacities of various microbial species (Bacillus subtilis, Pseudomonas aeruginosa, Ralstonia metallidurans CH34 previously Alcaligenes eutrophus CH34, Mycobacterium smegmatis, Saccharomyces cerevisiae) for ions of the lanthanide gadolinium (Gd³⁺). The uptake by sand of this element was also measured. Saturation curves and Scatchard models were established for all biosorbants used in this work. The results enabled us to determine the binding affinities and the maximum capacities for biosorption of Gd³⁺, which ranged from 350 μmol g⁻¹ for B. subtilis to 5.1 μmol g⁻¹ for S. cerevisiae. This study demonstrated the usefulness of optimisation of experimental conditions in biosorption investigations. Experimental results showed that biosorption could be influenced by the growth stage and by the composition of the growth medium of microbial cells. Finally, particular attention was given to the transfer of gadolinium ions from a loaded sand to a bacterial suspension. Received: 8 November 1999 / Received revision: 3 February 2000 / Accepted: 4 February 2000     

Patterns and Risks of Trichinella Infection in Humans and Pigs in Northern Laos

Several outbreaks of trichinellosis associated with the consumption of raw pork have occurred in Laos since 2004. This cross-sectional study was conducted in four provinces of northern Laos to investigate the seroepidemiology of trichinellosis in the human population and determine the prevalence and species of Trichinella infection in the domestic pig population. Serum samples and questionnaire data were obtained from 1419 individuals. Serum samples were tested for Trichinella antibodies by ELISA using larval excretory–secretory (ES) antigens and a subset of 68 positive samples were tested by western blot. The seroprevalence of Trichinella antibodies was 19.1% (95% confidence interval (CI) = 17.1–21.1%). The risk of having antibodies detected by ELISA using ES antigens increased with age, being of Lao-Tai ethnicity, living in Oudomxay province and being male. Tongue and diaphragm muscle samples were collected from 728 pigs and tested for Trichinella larvae by the artificial digestion method. Trichinella larvae were isolated from 15 pigs (2.1%) of which 13 were identified as T. spiralis by molecular typing; the species of the two remaining isolates could not be determined due to DNA degradation. Trichinella spp. are endemic in the domestic environment of northern Laos and targeted preventative health measures should be initiated to reduce the risk of further outbreaks occurring.     

Biofilms in Drinking Water Distribution Systems

Biofilms and loose deposits in drinking water distribution systems provide a mosaic of electrochemical and nutritive environments. Limiting biofilms requires a combination of actions with impact is relatively low as discussed in this article.     

Apolipoprotein CI is a physiological regulator of cholesteryl ester transfer protein activity in human plasma but not in rabbit plasma

Plasma cholesteryl ester transfer protein (CETP) activity is high in rabbits, intermediate in humans, and nondetectable in rodents. Human apolipoprotein CI (apoCI) was found to be a potent inhibitor of CETP. The aim of this study was to compare the ability of rabbit and human apoCI to modulate the interaction of CETP with HDLs and to evaluate to which extent apoCI contributes to plasma cholesteryl ester transfer rate in normolipidemic humans and rabbits. Rabbit apoCI gene was cloned and sequenced, rabbit and human apoCI were purified to homogeneity, and their ability to modify the surface charge properties and the CETP inhibitory potential of HDL were compared. It is demonstrated that unlike human apoCI, rabbit apoCI does not modulate cholesteryl ester transfer rate in total plasma. Whereas both human and rabbit apoCI readily associate with HDL, only human apoCI was found to modify the electrostatic charge of HDL. In humans, both CETP and apoCI at normal, physiological levels contribute significantly to the plasma cholesteryl ester transfer rate. In contrast, CETP is the sole major determinant of cholesteryl ester transfer in normolipidemic rabbit plasma as a result of the inability of rabbit apoCI to change HDL electronegativity.