Age determination using the apodeme structure in adult screwworm flies (Cochliomyia hominivorax)

A method of age determination of adult screwworm flies is described and documented. This method uses the diurnal differences in the deposition of apodeme layers as a basis for counting the age in days since eclosion. The method is accurate to plus or minus one day, and can be determined on meterial that has been dried, pinned, frozen, or preserved in ethanol or other fixatives.     

Effects of light and turbidity on feeding,growth, and survival of larval Delta Smelt (Hypomesus transpacificus,Actinopterygii, Osmeridae)

Hydrobiologia - Understanding how environmental factors—here, light intensity and turbidity—influence the feeding, growth, and survival of larval Delta Smelt is critical for optimizing...     

In vivo bioluminescence: A cellular reporter for research and industry

The detection of specific bacterial pathogens, indicator microorganisms and antimicrobial substances, and the recovery of microorganisms from sub-lethal injury, are all aspects of importance to industry which are currently being targeted using in vivo bioluminescence. In all instances, a key requirement for the application of bioluminescence is the establishment of a strict correlation between in vivo bioluminescence and cell viability, as determined by colony counting on agar plates. Comparative studies for biocides (phenol, chlorhexidine diacetate, phenol thioether), for a virucide (hypochlorite) and for cellular recovery of S. typhimurium from sub-lethal injury, all indicate that such a correlation is valid. Furthermore, real-time measurements of in vivo bioluminescence reveal a major population of bacterial cells that retain functional intracellular biochemistry, but are defective in their ability to replicate post of freeze injury.     

HIV as a surrogate marker for drug use: A re-analysis of the San Francisco Men's Health Study

Our analysis of drug use and morbidity data from a cohort of 1034 men yields the following results: 1) HIV infection is a strong indicator of drug use — HIV-positive respondents reported an average lifetime dose of recreational drugs (excluding marijuana) 2.3 times higher than HIV-negative respondents. 2) Homosexuality is a strong indicator of drug use — homosexual respondents reported an average lifetime dose 2.0 times higher than heterosexual respondents. 3) The incidence of AIDS-defining diseases was not limited to respondents infected with HIV, but was almost completely limited (98%) to respondents who reported using drugs. We also address a previous report (Ascheret al., 1993) that was based on the same database and purported to show that HIV alone correlates with the development of AIDS. Specifically, we show that the relationship between HIV infection and CD4+ T Cell loss is weaker than reported by Ascheret al., and provides little evidence for a causative relationship. These results support the hypothesis that long-term, habitual drug use can cause the conditions known as AIDS (independent of the presence of HIV), and refute the hypothesis that HIV alone causes these conditions independent of drug use.     

Red cell phenylalanine is not available for transport through the blood-brain barrier

The possibility that red cell-sequestered amino acids such as phenylalanine are available for transport through the brain capillary wall, i.e., the blood-brain barrier (BBB), in vivo was investigated in the present studies with the carotid artery injection technique. Control studies included the examination of the availability of red cell-sequestered solutes such as phenylalanine ord-glucose to liver cells in vivo using a portal vein injection technique. The results show that red cell-sequestered phenylalanine is not available for transport through the BBB or into rat liver in vivo, but human red cell-sequesteredd-glucose is available for uptake by liver following portal injection. Therefore, given favorable kinetics it is possible for red cell-sequestered solute to be available for uptake by tissues. However, in the case of neutral amino acids such as phenylalanine, red cell-sequestered amino acid is not available for transport through the BBB in vivo.