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One of the “nurse cell” functions of Sertoli cells is to provide lactate for the energy production in spermatocytes and spermatids. The present study shows that, as in porcine Sertoli cells, interleukin (IL)1β and follicle-stimulating hormone (FSH) increase lactate production in rat Sertoli cells (basal, 9.1 ± 1.0; FSH (100 ng/ml), 16.6 ± 2.0; IL1β (50 ng/ml), 13.3 ± 1.6 μg/μg DNA). Increments in glucose uptake (basal, 1083 ± 70; FSH, 2686 ± 128; IL1β, 1899 ± 74 dpm/μg DNA), lactic dehydrogenase (LDH) activity (basal, 36.6 ± 4.1; FSH, 52.2 ± 4.9; IL1β, 55.3 ± 5.1 mUI/μg DNA), LDH A mRNA levels, and redistribution of LDH isozymes are involved in these stimulatory effects. Differences in the period required by IL1β to increase glucose uptake, as compared with the porcine model, have been observed. In addition, tumor necrosis factor α (TNFα), one of the major stimulators for lactate production in porcine Sertoli cells, does not control the secretion of this glucose metabolite in rat Sertoli cells. Lactate production may be regulated differently among mammals.

The United States Environmental Protection Agency (U.S. EPA) requires reference spectra to support its gas chromatography/Fourier transform infrared (GC/FT-IR) routine environmental monitoring program. Although on-the-fly (OTF) techniques are needed to satisfy the Agency's high sample throughput requirements, the FT-IR vapor-phase reference spectra produced by the Agency thus far have been measured under static conditions. Accordingly, the OTF spectra of 47 environmentally important compounds have been measured by packed-column GC/FT-IR under carefully controlled conditions. The compounds selected for spectral measurement are currently regulated by the U.S. EPA and generally represent compound classes which are absent, or poorly represented, in the current U.S. EPA data base (e.g., organochlorine and organophosphorus pesticides). Where feasible, the Co-blentz Society guidelines for the measurement and recording of vapor-phase infrared reference spectra and supporting data were followed. The sensitivity order of the reference compounds as determined by the strongest spectral band and the quantity of compound injected on-column was, organophosphorus and thio-organophosphorous > aliphatic organochlorine ≥ polynuclear aromatic.

Organic vapors in ambient air, at or near an industrial site in Baltimore, Maryland, were collected by adsorption on a sorbent of porous polymer (Tenax GC, 35/60). The pollutants were recovered by thermal desorption and analyzed by gas-liquid chromatography mass spectrometry computer using capillary glass SCOT columns. N-Nitrosodimethylamine was identified from its mass spectrum as a constituent of the atmosphere in the areas sampled. The identification of this compound was confirmed by comparison of its mass spectrum with that of authentic N-nitrosodimethylamine; identical retention times of unknown and authentic compound on three different capillary columns were observed.