Relationship of maternal amino acid profiles at 25 weeks of gestation to fetal growth

In a study of the relationship of maternal nutrition to fetal development, the free amino acid concentration was determined in the plasma of 43 subjects sampled between the 20th to 30th (25 +/- 3.7) week of pregnancy. Significant positive correlations were found between mothers' 25-week plasma levels of aspartic acid, serine, alanine, tyrosine, ornithine, and arginine, and babies' size at birth. The concentration of total free amino acids in plasma from mothers of fetally malnourished infants, was significantly lower than that from mothers having normal babies. The branched chain amino acids isoleucine and valine were at normal levels, suggesting a sparing effect for these amino acids.     

Pesticide photoproducts: generation and significance

As with the parent pesticide, the significance of a pesticide photoproduct depends on its concentration in a given environmental compartment, its toxicity, and exposure of the organism or ecosystem of interest. This requires an understanding of the production and environmental chemistry of each photoproduct as well as its toxicity. While these data are generally available for the parent pesticide, they are rarely determined in detail for the photoproducts. Although the environmental photochemistry of each pesticide is different, some generalizations can be made. Photochemical oxidations, reductions, hydrolytic reactions, and isomerizations often generate products identical to those of metabolic and nonbiological transformations. The chemistry and environmental stability of each individual photoproduct can be substantially different from those of the original pesticide and other products. With several notable exceptions, however, photoproducts are generally less stable to environmental forces and less toxic than the parent pesticide, at least to the target organism. A most significant exception is the P = S to P = O conversion in the organophosphorus insecticides. This sunlight promoted reaction is important in treated fields and has been implicated as a cause of injury to farmworkers.     

Clinical neurologic assessment tool: development and testing of an instrument to index neurologic status

The clinical neurologic assessment tool (CNA) is a 21-item instrument assessing response to verbal and tactile stimulation, ability to follow commands, muscle tone, body position, movement, chewing, and yawning in the patient with head trauma. The CNA was developed to detect subtle changes in the patients' neurologic status that may indicate transitions in the comatose state. The CNA has been extensively pilot tested. Reliability determined by using Cronbach's alpha revealed an internal consistency of 0.96. Concurrent validity testing with the Glasgow Coma Scale indicated a strong positive correlation, r = 0.94. Construct validity was assessed with factor analysis using 0.50 for a loading criterion. Three factors were demonstrated: general level of consciousness, muscle tone and resistance, and chewing or yawning. Discriminant function analysis revealed that the CNA scores correctly classified 95.1% of the patient observations into their respective Glasgow Coma Scale categories. The CNA is reliable, valid, convenient, and easily scored and captures the subtle changes in the patient with head trauma.