Novel functional association of rat testicular membrane-associated cytosolic glutathione S transferases and cyclooxygenase in vitro.

Aim: To analyze the role of cytosolic glutathione S-transferases cGSTs and membrane-associated cytosolic GSTs macGSTs in prostaglandin biosynthesis and to evaluate the possible interaction between glutathione S-transferases GSTs and cyclooxygenase (COX) in vitro.

Methods: SDS-PAGE analysis was undertaken for characterization of GSTs, thin layer chromatography (TLC) to monitor the effect of GSTs on prostaglandin biosynthesis from arachidonic acid (AA) and spectrophotometric assays were done for measuring activity levels of COX and GSTs.

Results: SDS-PAGE analysis indicates that macGSTs have molecular weights in the range of 25-28 kDa.

Evidence for the association of synaptotagmin with glutathione S-transferases: implications for a novel function in human breast cancer.

Objective: To analyze the pattern of changes in GSTs in cancerous and adjacent non-cancerous tissues obtained from breast cancer patients undergoing surgery.

Design And Methods: Cytosolic GST purification, assay of GST, protein expression levels, and GST-synaptotagmin association were analyzed using standard biochemical techniques like GSH-affinity purification, spectrophotometry, SDS-PAGE, Western blots, and matrix-assisted laser desorption and ionization-time of flight (MALDI-TOF).

Results: GST activity in cancerous tissues (0.

Expression of cyclooxygenase-2 in rat testis.

Cyclooxygenase, the rate-limiting enzyme in the production of prostaglandins, exists in two isoforms, the constitutive cyclooxygenase 1 (Cox-1) and the inducible cyclooxygenase 2 (Cox-2). Cox-1 is involved in homeostatic functions while Cox-2 is implicated in various pathological processes such as inflammation and cancer. The present study describes the constitutive expression of Cox-2 in immature and mature rat testis, primarily localized in the spermatogonial cells.

A modified protocol for quantitative fit testing using the PortaCount.

A modified quantitative fit testing method has been developed for testing half masks using the TSI PortaCount respirator fit tester. This approach focuses on shortening the time for each exercise during fit testing; however, the shortened protocol is applied only to the very good-fitting masks. For marginal-fitting masks, the testing is carried out according to the full Occupational Safety and Health Administration (OSHA) respiratory protection standard (29CFR1910.

New experimental studies of the basic performance characteristics of aerosol samplers.

The study of the basic physical performance characteristics of aerosol samplers, like those used in the occupational hygiene setting, will provide insights to enable the improved development of new instruments and cost-effective testing procedures. These will be required as the new particle size-selective sampling criteria become the basis of new occupational exposure standards. A new body of work is being conducted, in which the factors influencing sampler performance are being investigated using idealized samplers of spherical shape in small wind tunnels.