The burnout of nursing staff working with challenging behaviour clients in hospital-based bungalows and a community unit

The increasing presence of genotoxic chemicals in the aquatic environment has led to the development of both in vivo and in vitro assays for target species. The fish population represents an important level of aquatic ecosystems that can be threatened by increased environmental pollution. The authors have studied the DNA pattern of the RTG-2 fish cell line, a fibroblast-like cell line, derived from rainbow trout (Oncorhynchus mikyss), to use this cell line as an in vitro system to study genotoxicity by means of random amplified polymorphic DNA primers (RAPDs). A constant pattern in the DNA band is essential when an organism or cell line is used to detect DNA alterations produced by genotoxic environmental chemicals. DNA fingerprints with RAPDs were obtained for RTG-2 by testing 26 single and 70 pairwise combinations of primers. Different methods of DNA extraction (chelating resin, salting out, and phenolization), the influence of spectrometric measures at 320 nm in the 260/280 quotient to quantify DNA extracts, genomic DNA and primer concentrations, annealing temperatures, and cell line passage were studied in the cell line characterization. RAPD products were identified by agarose gel electrophoresis. The good results obtained should allow the use of this system as a possible tool for detection of the genotoxicity of aquatic pollutants.     

Needed research on the interactions of certain parasitic diseases and nutrition in humans

For the purpose of assigning priorities for research, each of the following parasitic disease is examined in regard to its affect on the nutritional status of the host: schistosomiasis, malaria, amebiasis, giardiasis, ascariasis, and hookworm. The epidemiology, diagnosis, immune response to, and available therapies for these diseases are discussed. It is suggested that highest priority be given to three diseases: hookworm, ascariasis, and schistosomiasis, because they can be treated successfully, diagnosed easily, and have a high prevalence.     

Valyl-transfer RNA formation stimulated by monovalent cations and spermine in rat liver

The effects of hypothalamic disconnection on body temperature and hypothalamo-pituitary-adrenal activity following acute and repeated exposures to heat were studied. Intact male rats, or animals with complete posterior or anterior hypothalamic disconnection, were exposed to a temperature of 36 degrees C and a relative humidity of 35-45%. In the complete posterior and anterior hypothalamic disconnected rats the basal Tre was higher than that of the intact rats; the rise in Tre following heat exposure was lower in the operated rats than in the intact animals. All the experimental animals, except for those with anterior hypothalamic disconnection, showed a significant inhibition of corticosterone release on exposure to heat for 30 min, but no inhibition was observed in any of the disconnected rats when they were exposed to heat for 120 min. These results suggest that the main stimulus for ACTH release, during the first 30 min of heat exposure, is mediated by a neural input through the posteroir hypothalamus and this is followed by a nerural and/or humoral mechanism which enables the animals to increase their corticosterone secretion.     

Anatomy of the lumbar spine

The macroscopic courses of the posterior primary rami in the lumbar spine are described and illustrated from fresh cadaver dissections.     

Factors limiting the domestic density of Triatoma infestans in north-west Argentina: a longitudinal study

Reported are the environmental and demographic risk factors associated with the domestic infestation and density of Triatoma infestans in three heavily infested rural villages in Santiago del Estero Province, Argentina. In a one-factor unadjusted analysis, the number of T. infestans captured per person-hour was associated significantly and negatively with the use of domestic insecticides by householders, type of thatch used in the roofs and the age of the house; and positively with the following: degree of cracking of the indoor walls and presence of hens nesting indoors. In one model, using multiple linear regression and a backward stepwise elimination procedure, most of the variation in the overall abundance of T. infestans was explained by insecticide use and the presence of hens nesting indoors; in another model using the same procedure it was explained by insecticide use, bug density in 1988 and previous spraying with deltamethrin in 1985. Variations in bug density per capture stratum (household goods, beds, walls and roof) were explained by the bug density in other strata and by one or two of the following risk factors: hens nesting indoors, type of roof, presence of cracks in the walls and number of people living in the house. Bug density might be locally controlled by the availability of refuges in the roofs and walls, by the presence of hens nesting indoors and by the use of domestic insecticides. Certain local materials, such as a grass known as simbol, could be successfully used in rural housing improvement programmes aimed at reducing the availability of refuges for insects in the roof.