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Spermatogenesis is a programmed developmental process characterized by the inactivation of certain genes and the activation of other, testis-specific genes. Synthesis of unique gene products such as LDH-C4 and cytochrome ct occurs only at precise stage of germ cell formation. The developmental sequences of gene activation for these proteins was observed by immunohistochemical procedures. LDH-C4 is first detectable during mid-pachytene of the primary spermatocyte. The C subunits appear to be uniformly distributed throughout the cytoplasm of the spermatocyte. The mid-pachytene stage also marks the first appearance of cytochrome ct. The association of this electron transport protein with spermatocyte mitochondria is reflected in a granular fluorescence of specific antibody-treated sections of testis. Neither the C subunit of LDH, nor cytochrome ct appear in leptotene or early pachytene primary spermatocytes. These analyses indicate that there is stage-specific protein synthesis in the primary spermatocyte which is characterized by differential activation of the LDH-C locus and of the gene coding for cytochrome ct.

This study deals with the effect of deamidation and C-terminal truncation on the potency of an octadecapeptide pigment-dispersing hormone (PDH: Asn-Ser-Gly-Met-Ile-Asn-Ser-Ile-Leu-Gly-Ile-Pro-Arg-Val-Met-Thr-Glu-Ala- NH2), first described as light-adapting distal retinal pigment hormone (DRPH) from Pandalus borealis. Bioassay of synthetic analogs for melanophore pigment dispersion in destalked fiddler crabs (Uca pugilator) showed that deamidation causes a 300-fold decrease in potency. The analogs 1-17 NH2 and 1-16 NH2 were about 3 times more potent than 1-18-OH. Further truncation led to decreases in potency, with the peptide 1-9-NH2 being the smallest C-terminal deletion analog to display activity (0.001% potency). Smaller analogs (1-8-NH2, 1-6-NH2 and 1-4-NH2) were inactive when tested in doses as high as 500 nmoles/crab. On the basis of our earlier work on N-terminal deletion analogs and the present findings the residues 6 to 9 seem to be important for PDH action.

The pharmacokinetics of acyclovir administrated orally in a dose of 200 mg every four hours, five times a day to adults with herpes progenitalis was determined. Peak plasma acyclovir levels are found 1.5 to 1.75 hours after oral administration; peak levels range from 1.4 to 4.0 microM with a mean of 2.5 microM. Acyclovir levels in saliva are well correlated with simultaneous plasma levels, saliva levels being approximately 13 percent of plasma levels. Simultaneous plasma and vaginal secretion acyclovir levels are poorly correlated; peak levels in vaginal secretions range from 0.5 to 3.6 microM.

Isoelectric focusing (IEF) and histochemical techniques were used to examine the genetics, postnatal development and biochemical properties of ocular oxidases (EOXs) among inbred strains of mice. The designation as EOX was made on a provisional basis, since the 'natural' substrate(s) for this enzyme have not been identified. Five major forms were resolved from adult animals, which exhibited high activity in murine lens and low activity in the cornea. An additional ocular oxidase was observed in neonatal animals. Genetic analyses demonstrated that one of these enzymes (EOX-1) is encoded by a locus (Eox-1) which is closely linked with, but distinct from, the aldehyde oxidase (Aox) gene complex on chromosome one of the mouse. These results support the proposal that ocular oxidases are distinct from the major liver AOXs in this organism.