The role of microsomal oxidation processes in the development of haloperidol tolerance during melatonin administration and epiphysectomy in rats

A pineal hormone melatonin (1 mg/kg, 24 days) facilitated the formation of tolerance to haloperidol and eliminated the changes produced by it in the processes of microsomal oxidation in rats. Pinealectomy yielded the opposite result. After pinealectomy the normalizing effect of the hormone on the condition of the liver monoxygenase system and the effects of haloperidol weakened.     

Prolactin and known modulators of rat splenocytes activate nuclear protein kinase C

Prolactin (PRL) and other trophic factors rapidly activate a nuclear pool(s) of protein kinase C (nPKC) in purified splenocyte nuclei. The PRL also enhanced [2-3H]glycerol incorporation into nuclear mono- and triacylglycerol. An assay was devised which not only probed the ability of the hormone to activate protein kinase C (PKC) but also demonstrated the presence of nuclear substrates. Using this methodology, a biphasic concentration-response curve to PRL was observed. Heterologous species of PRL and various growth factors also activated nPKC. The PRL-induced nPKC stimulation was antagonized by various immunomodulators, G protein-coupling inhibitors, PKC inhibitors, a calmodulin inhibitor, and a peripheral benzodiazepine agonist and antagonist. A monoclonal antibody to PKC, anti-rat PRL antiserum and a monoclonal anti-rat PRL receptor antibody antagonized PRL-induced PKC-dependent nuclear phosphorylation, further implicating nPKC and a PRL receptor-mediated activation process. Nuclear PKC may be a major target for trophic regulation in response to both positive and negative growth signals.     

Medical technology in the United States. The last decade.

This paper reviews the evolution of U.S. policy toward medical technology in areas such as cost containment, regulation of devices and drugs, and third party reimbursement. In addition the authors chronicle the diffusion of major medical technologies, procedures, and organizational innovations in the United States. Finally, the article provides tentative observations on the effect of recent policy changes and concludes with some recommendations for the future.     

Recycling suitability of wash waters from mosquito abatement vehicles and equipment into spray diluent

In response to changing laws as well as increased concern over environmental pollution, there is a current need to examine the best means of disposal of wash water generated by mosquito abatement operations. A study of wash waters from 6 central California mosquito abatement districts shows that herbicide levels were low enough so as not to preclude the use of these waters for recycling back into insecticide spray diluent. In one case, oil levels were high and an oil/water separation is probably necessary to prevent gum formation and clogging of spray equipment. Recycling of wash waters appears to be a feasible solution to the disposal problem once water contaminant levels are defined.     

Hybridization of laboratory strains of sibling species A and B of Anopheles quadrimaculatus

Adult mosquitoes of the Anopheles quadrimaculatus complex were collected from Montgomery County, AL (MON) and Alachua County, FL, (KBG) and laboratory stocks of species A and B were established through a selection procedure employing isofemale lines. Progeny from a cross of species B females to ORL males were usually semisterile females and sterile males. Progeny of the reciprocal cross were also semisterile females and sterile males, but the sex ratio was variable and ranged from normal to no males because of male mortality during the pupal stage. Conspecific crosses between strains from the two locations resulted in fertile offspring. Crosses between the sibling species from the two locations invariably gave semisterile females and sterile males (or lethal effects). This evidence confirmed previous data from hybridization and electrophoretic analyses of field populations indicating that Anopheles quadrimaculatus is a species complex.     

A new member of the Anopheles quadrimaculatus complex, species C

A new member, species C, of the Anopheles quadrimaculatus complex was recently found in collections from the northwest coast of Florida. This new species cannot be differentiated from the other 2 species with available taxonomic keys. Evidence for this taxon as a sibling species includes data on hybrid sterility and distorted sex ratios in the progeny of crosses to species A and B, chromosomal differences, and diagnostic allozymes.     

Unusual central chorioretinitis as the first manifestation of early secondary syphilis

Three young, otherwise healthy patients had a similar picture of unilateral central chorioretinitis associated with severe visual loss. Fluorescein angiography disclosed diffuse leakage under the neurosensory retina in the posterior pole, associated with multifocal areas of staining along the retinal vessels. Systemic examination showed a positive fluorescent treponemal antibody absorption test and a sharp increase in VDRL titers, indicative of active secondary syphilis. The patients responded dramatically to penicillin treatment, with visual recovery and resolution of the fundus lesions.     

Progressive peripheral cone dysfunction

A 22-year-old man had a three-year history of progressive day blindness, most notably peripherally, and denied difficulty with central vision or color vision. Visual function studies demonstrated a diffuse dysfunction of the photopic system and normal scotopic function. The central cone function, however, was essentially normal. Visual acuity was 20/20 in each eye, results on AO-HRR and Ishihara color plate testing were normal, color naming visual fields demonstrated color discrimination in the central 10 degrees, and foveal adaptation was normal.