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Insulin and 12-O-tetradecanoyl phorbol-13-acetate (TPA) induce both glucose uptake and translocation of protein kinase C (PKC) from cytosol to membrane in insulin-sensitive tissues as previously reported by several investigators. We examined insulin-mediated PKC beta I, beta II, and epsilon translocation from cytosol to cytoskeleton, and expression of PKC alpha, beta I, beta II, gamma, and epsilon isoforms using the reverse transcription polymerase chain reaction (RT-PCR) method during treatment with insulin for 240 min in rat adipocytes. Insulin-induced increases in PKC beta I, beta II, and epsilon were greater in the cytoskeleton fraction than those in the membrane fraction. Insulin induced time-dependent increases in PKC alpha, gamma, epsilon and zeta mRNA levels for up to 240 min (555%, 117%, 236% and 138% increase, respectively). TPA also induced time-dependent increases in PKC alpha and gamma (34% and 500% increase, respectively) but not in PKC zeta. However, PKC beta I mRNA was decreased for up to 60 min and then maintained at under the basal level during stimulation with insulin and TPA. On the other hand, PKC beta II mRNA was markedly increased for up to 240 min. These results suggest that insulin-regulated PKC alpha, gamma and epsilon mRNA levels and PKC beta mRNA alternative splicing may occur in rat adipocytes.

Wortmannin is known to be an inhibitor of myosin light chain kinase and phosphatidylinositol 3-kinase (PI 3-kinase) (J. Biol. Chem. 268, 25846, 1993). We studied the effects of wortmannin on insulin- and 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced glucose uptake, purified PKC activity and in vitro 80 kDa protein phosphorylation to elucidate the relationship between insulin-induced PI 3-kinase and PKC activations. Pretreatment with 10(-12)-10(-6) M wortmannin for 60 min resulted in a dose-responsive reduction of 10 nM insulin-stimulated glucose uptake in rat adipocytes. Pretreatment with 10(-6) M wortmannin resulted in 80% and 20% decreases of glucose uptake stimulated by insulin and TPA, respectively. Partially purified rat brain PKC activity and 80 kDa protein in vitro phosphorylation of rat adipocyte cytosol by addition of Ca2+ and phospholipid were dose-dependently decreased by 10(-8)-10(-6) M wortmannin; 20% decrease of PKC activity and 50% decrease of 80 kDa protein phosphorylation by 10(-6) M wortmannin were observed. These results suggest that wortmannin has a potent inhibitory effect on PI 3-kinase and a weak inhibitory effect on PKC activity, and both effects cause a significant inhibition of insulin-stimulated glucose uptake in rat adipocytes.

During the first 10 days after birth in the rat there are a succession of major developmental stages in the retinotectal pathway. During most of this time, the only recordable event in the superior colliculus is spontaneous activity. We studied and characterized this spontaneous activity, hypothesizing that it could play an important role in pathway development. The spontaneous discharges are detectable on postnatal day 5 (P5). After P5, the number of spontaneously active cells per penetration increases up to P10, after which they decrease to adult-like levels by P14-P15. Between P5 and P10, the spontaneous discharges exhibit several patterns of activity, from constant firing to intermittent bursts with periods of quiescence, without any bearing to age. We isolated the retina and superior colliculus by injecting xylocaine onto the optic nerve and found no change in collicular activity. While this suggests that the spontaneous activity in the colliculus is independent of the retina at the ages studied, the opposite experiment, i.e., electrically stimulating the optic nerve, resulted in increased firing by collicular neurons, perhaps via nonclassical synaptic transmission. Finally, we compared interval histograms for spontaneously active cells between P5 and P15. The histograms suggest that at certain ages, spontaneous firing is more regular; moreover, these ages precede major functional advances, e.g., onset of numerous spontaneously firing cells at P6, the first response to optic nerve stimulation at P10, and the first light-evoked response at P12-P13. Our results support the hypothesis that spontaneous activity in the neonatal superior colliculus has a role in development of the retinotectal pathway, but the data also indicate that classical synaptic transmission is not involved.

A 50-year-old tetanic woman with hypomagnesemia is described. She had partial resection of the stomach and the jejunum at the age of 20 years. Lack of parathyroid hormone (PTH) function was indicated by hypocalcemia, hyperphosphatemia and high tubular reabsorption of phosphate. However, both plasma concentration of PTH and nephrogenous cAMP were normal. Administration of magnesium sulfate completely normalized serum phosphate and tubular transport of phosphate with only a modest increase in nephrogenous cAMP. The present findings suggest that phosphaturic action of PTH is impaired in magnesium deficiency and that steps distal to cAMP production may be responsible for the renal refractoriness to the hormonal action.

We examined effect of insulin or 12-O-tetradecanoyl phorbol 13-acetate (TPA) on the subcellular redistribution of protein kinase C isoforms in rat adipocytes. Total Mono Q column-elutable novel PKCs (nPKCs) which are Ca(2+)-independent and phospholipid-dependent protein kinases, decreased in the cytosolic fraction and increased in the membrane fraction during treatment with insulin or phorbol ester for 10 min. Immunoblot analysis of novel PKCs, -epsilon, -delta and -zeta, showed that insulin stimulated the translocation of these PKC isoforms from cytosol to membrane, similar to the translocation of conventional Ca2+/phospholipid-dependent PKCs (cPKCs), -alpha, -beta, and -gamma. Phorbol esters stimulated the translocation of PKC-alpha, -beta, -gamma, -epsilon and -delta, but not PKC-zeta. These results suggest that (a) insulin and phorbol esters similarly stimulate the translocation of each PKC isoform except for PKC-zeta, and (b) the translocation of both nPKCs and cPKCs occurs during insulin and TPA actions in rat adipocytes.

Concentrations of Tegafur, 5-FU, and Uracil were measured in the tissues and serum of 32 patients with malignant head and neck tumors after administration of UFT or UFT and OK-432. Of the 32 patients, 15 patients were treated with UFT alone and 17 patients with a combination of UFT and a clinical dose of OK-432. The level of 5-FU was higher in the tissues and serum in the patients who received the combined administration of UFT and OK-432 than in those the received UFT alone. In particular, levels of 5-FU in tumor tissue and metastatic lymph node tissue were higher than 0.05 micrograms/g even 14.6 hours after the last administration of UFT. No significant undesirable interactions between UFT and OK-432 were exhibited during combination therapy of these agents in clinically administered doses. From our satisfactory results, clinical cures would be expected by the combined immuno-chemotherapeutic action of these agents.

Electrophysiological activity in the neonatal rat superior colliculus was recorded to measure neuronal and synaptic activity, and, therefore, functional development. Neonatal rat pups were studied from five days to two weeks of age. The earliest activity in the superior colliculus were spontaneous discharges at a frequency of one unit per animal on postnatal day 6 (P6). Spontaneously discharging units were more numerous at P8, and the number peaked on P10. The first clear response to optic nerve stimulation was seen on P10, with relatively long and variable latencies. By P14, electrically evoked responses had much shorter latencies. The results are in line with the first response to light flash in the superior colliculus at P12/13. The evidence suggests that functional development of the rat retinotectal pathway begins at the end of the first week after birth, and that much of the functional maturation occurs mainly during the second week after birth.

Intraocular injections of several different retrograde tracers were made in albino rats. Retrogradely filled neurons were observed in two locations: the medial pretectal area and the contralateral periaqueductal grey matter, indicating that the pretectum and the mesencephalon are sources of centrifugal innervation to the rat retina.

Wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was used to study transneuronal transport in the developing rat visual pathways. Intraocular injections of WGA-HRP were made in neonatal albino rat pups at different ages from the day of birth, postnatal day 0 (P0), to one month of age. Transneuronal labeling in geniculostriate fibers and in tectoparabigeminal terminals was observed as early as P1 and showed little change with eye-opening. However, at early ages, consistent transneuronal labeling was found to require injection of up to 4 times the amount of tracer (0.18 mg WGA-HRP) as adults (0.04 mg WGA-HRP), delivered in two injections. Control injections of HRP alone produced heavy anterograde labeling at all ages, without requiring increased injections. The results suggest that transneuronal transport precedes synaptic transmission, and may illustrate a mechanism for exchanging molecules between neurons. One explanation for the requirement of increased tracer is that axonal and/or transneuronal transport of WGA-HRP may be selectively limited to certain cells in the postnatal retina.

The tracer, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP), was used as a transneuronal marker in the macaque monkey to study retino-geniculo-striate pathway terminals in area 17. Concomitantly, we stained matching sections for metabolic capacity using the cytochrome oxidase staining technique. Terminal labeling by WGA-HRP and cytochrome oxidase activity staining revealed duplicate patterns in layers II and III, IVA, IVC alpha, IVC beta, and VI. The absence of WGA-HRP-labeled neuronal cell bodies in area 17 supports the conclusion that WGA-HRP is a transsynaptic marker in the macaque visual pathways.

Horseradish peroxidase (HRP) and HRP conjugated to wheat germ agglutinin (WGA-HRP) were used as anterograde tracers in the monkey visual pathways. In addition to known optic pathways, we observed labeled fibers which left the lateral terminal nucleus of the accessory optic system, traveled around the cerebral peduncle, and could be followed as far as the medial terminal nucleus.

The lectin tracer, wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP), was injected into the entorhinal cortex in rat and monkey brains. Tracer labeling was followed in the entorhinal projection to dentate gyrus and hippocampus, i.e. along the perforant pathway. Besides labeling perforant pathway terminals in the outer two-thirds of stratum moleculare in the dentate gyrus, reaction product was also observed within stratum granulosum. We conclude that labeling of dentate granule cells was the result of anterograde transsynaptic transport of WGA-HRP. The evidence thus provides an example of anterograde transsynaptic transport: in the limbic system; and at an excitatory synapse.

The fine structure of the principal compound eye of the shrimp, Palaemonetes, was studied under conditions of light and dark adaptation. Ommatidium the situation in other decapod crustaceans. Light and dark adapted eyes differ in that the rhabdom changes its shape; morphological evidence suggests a possible sequence of events involving production, utilization, and degradation of photoreceptor membrane, a discontinuous process occurring only during changes from light to dark and dark to light. A hypothesis of membrane turnover is proposed.

Twenty-one previously untreated cases, who underwent the same protocol at our department from January 1984 until December 1986, were investigated. The following results were obtained. Non-Hodgkin's lymphoma accounted for 10.5% of all the head and neck malignant tumors at our department. The age range was from 23 to 76 years of age and had a peak in the forties. Fourteen were male and seven were female. According to the stage distribution, six cases were stage I (28.6%), nine were stage II (42.9%), four were stage III (19.0%) and two were stage IV (9.5%). Stage I and II accounted for 71.4%. By site grouping, palatine tonsil and nasal cavity accounted for 38.1%, respectively. Surgical therapy was presumably useful for a solitary lesion which resisted all conservative therapies. By combined therapy with radiotherapy, VAPE-Chemotherapy and OK-432-immunotherapy, the survival rates were 100% (stage I), 77.8% (Stage II), 50% (stage III) and 50% (stage IV). The mean survival rate was 76.2%.

The transport of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was studied in rat olfactory pathways. After applications of tracer to the vomeronasal organ, the olfactory epithelium or injections into the olfactory bulb, WGA-HRP reaction product was observed in second-order neuron terminal areas of each pathway, e.g. within posteromedial cortical amygdaloid nucleus, primary olfactory cortex and contralateral primary olfactory cortex, respectively. The results indicate that anterograde transsynaptic transport of WGA-HRP occurs in olfactory pathways, as has been shown in visual, somatosensory and limbic systems, and thus, anterograde transsynaptic transport may be a mechanism for neurons to exchange materials and/or messages.

Wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) is a neuroanatomical tracer which is transported transneuronally. In order to investigate whether transport of WGA-HRP is across synapses, labeling was studied in the developing retinotectal pathway where it is known that enucleation results in increased ipsilateral synaptic connections from the remaining eye. While little or no transneuronal labeling was evident in controls, after enucleation transneuronal labeling was consistently observed. Furthermore, the critical period for enucleation-induced transneuronal labeling coincides with the known critical period for enucleation-induced neuronal survival and synaptic formation. The results suggest that transneuronal exchange of WGA-HRP depends on the presence of synapses, and is therefore transsynaptic.

Horseradish peroxidase (HRP) and wheat germ agglutinin conjugated to HRP (WGA-HRP) were used as anterograde tracers to study the macaque monkey retinofugal pathways. Labeled axons were mapped beyond the lateral geniculate nucleus to the inferior (PI) and medial (PM) pulvinar nuclei, where they terminated. Retinofugal fibers project to the medial part of PI, adjacent to the brachium of the superior colliculus. A smaller projection to PM leaves the ventrolateral aspect of the lateral geniculate nucleus and travels parallel to the stria terminalis to reach the dorsal surface of the thalamus and PM. HRP reaction product was bilateral in PI and predominantly contralateral in P)M.

Wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) was injected intraocularly in monkeys and rats. All known primary visual pathways were labeled and, in addition, ocular dominance columns in visual cortex were labeled in monkey, and in rat, parabigeminal, oculomotor, thalamic reticular, and visual cortical areas were labeled as well as neuronal soma in superior colliculus. We conclude that WGA-HRP is a useful transneuronal marker for visual pathways.

Visual pathways were studied using horseradish peroxidase (HRP) as an anterograde tracer after intraocular injections in rats and monkeys. Retinal axons continue caudally from the stratum opticum of the contralateral superior colliculus at the medial and lateral sides of the superior colliculus. Fibers near the midline spread out as a flat sheet within the pericentral nucleus of the inferior colliculus. The optic axons travel through the dorsal pericentral nucleus and some reach the posterior pericentral nucleus, but their numbers diminish along the route, suggesting that the fibers terminate. The fact that a similar pathway was observed in rodent and primate suggests that the retino-pericentral nucleus pathway exists in other mammals.

Retinal projections in rats were studied using anterograde horseradish peroxidase (HRP) tracing and electron microscopic (EM) degeneration. HRP-labeled axons were observed to leave the optic tract in the vicinity of the lateral geniculate nucleus and enter the stria terminalis where they coursed anteriorly to the bed nucleus of the stria terminalis (BNST), and the anterodorsal (TAD) and anteroventral (TAV) thalamic nuclei. After enucleation, selected areas studied with EM confirmed that retinal presynaptic terminals are located in the BNST and TAV. These results support the finding of Conrad and Stumpf that the retina has a direct link to the limbic system.

Horseradish peroxidase (HRP) labeled neuronal somas were consistently found in the medial pretectal area after intraocular injection of HRP. The labeled cells represent the source of centrifugal fibers to the rat retina.

The cause-specific mortality experience of 2,509 active and retired members of the Oil, Chemical, and Atomic Workers International Union (OCAW) who worked at three oil refineries in the Beaumont/Port Arthur area of Texas was examined to determine whether there might be unusual patterns of fatal disease related to workplace exposures. Deaths that occurred between 1943 and 1979 were identified from membership records of the OCAW headquarters in Denver and from the records of union locals in Texas which represent workers at the three refineries. Death certificates were obtained from state vital records offices for the decedents. Cause-specific Proportionate Mortality Ratios (PMRs) were calculated using the mortality experience of the U.S. general population as a standard. Excess mortality from stomach cancer occurred among active union members who worked at Refinery A and among active and retired members who worked at Refineries B and C. PMRs for leukemia, multiple myeloma, and other lymphomas were elevated, especially among retired workers. Relative frequencies of brain tumor deaths were significantly elevated among active members at all three refineries and slightly elevated among retirees at Refineries A and C. Findings suggest that oil refinery workers may have elevated risks of these cancers and indicate that more definitive studies are necessary.

The fine structure of the accessory eye of the shrimp, Palaemonetes, was studied after light and dark adaptation. Adjacent to the principal compound eye, the accessory eye is a small compound eye composed of about 20 ommatidia which are smaller in structure to the ommatidia of the principal compound eye. During dark adaptation, rhabdomal microvilli increase in length; however, little pigment migration occurs. The implications of these changes in relation to the function of the accessory eye are discussed.