Public Response to Official Information on Cancer and Cancer Clusters

Official information about cancer and cancer clusters from state health departments clashes with lay views. A few studies have covered site-specific communication by telephone and public meetings, and hypothetical messages, but not generic information actually provided. Public response to such information was probed with a random survey of New Jersey households (n = 327), part of a quasi-experiment contrasting the agency's cognitive message and an alternative message adding procedural and affective information. Respondents rated both information types as understandable, helpful, and trustworthy, particularly among those trusting the agency, agreeing with officials’ views of facts, and with low concern about local clusters. Anxiety about cancer, aversion to uncertainty, cancer experience, and familiarity with clusters or the agency did not affect responses. Agreeing with officially defined facts (knowledge) was associated with trust in the agency and concern about clusters, but scepticism about expert knowledge. Information exposure increased trust, belief in expert knowledge (except on whether cancers cluster), and (some) factual knowledge, but also increased self-reported concern among those already concerned. These findings suggest that, absent specific learning, people believe scientific information is understandable, helpful, and trustworthy when they already trust experts and institutions; people with prior distrust offer less positive evaluations.     

Structure of an intermediate in the replication of bacteriophage φX174 deoxyribonucleic acid: The initiation site for DNA replication

Replicative form DNA composed of a closed complementary strand and a discontinuous viral strand has been isolated from cells infected with bacteriophage φX174 during the period of single-strand DNA synthesis. This RFII DNA was degraded by the restriction enzyme from Hemophilus influenzae, endonuclease R, and the products analyzed by polyacrylamide gel electrophoresis. The results indicate that there are two types of discontinuity in the viral strands of these molecules: (1) 65% of the molecules contain a gap, which causes a discrete increase in mobility of a specific restriction enzyme fragment, R3. This gap can be selectively repaired with Escherichia coli DNA polymerase I and nucleoside triphosphates, but the molecules are not converted to RFI by addition of E. coli polynueleotide ligase to the reaction mixture. Approximately 30 moles of radioactive TTP are incorporated per mole of RF DNA. (2) 35% of the RF molecules contain a discontinuity, which does not result in a detectable change in mobility of any restriction enzyme fragment. These RF molecules can be converted to RFI by the action of ligase and polymerase I in the presence of nucleoside triphosphates, with incorporation of only approximately one mole of radioactive TTP, specifically into fragment R3, per mole of RF DNA.When the reaction of late RFII DNA and polymerase I is allowed to proceed beyond the repair of the discontinuity, radioactive nucleotides are incorporated into endonuclease R fragments adjacent to R3 in the 5′ → 3′ direction. This technique was utilized to determine a partial order of endonuclease R fragments in φX174.These results suggest that the synthesis of single-strand DNA is initiated from a unique point in cistron A and proceeds clockwise round the φX174 genetic map (cistron order: ABCDEFGH). A comparison of these results with other studies on φX174 suggests that DNA synthesis in all stages of φX174 replication may be initiated from a specific locus on the genome, at or near cistron A.     

Differential Phosphorylation of τ by Cyclic AMP-Dependent Protein Kinase and Ca2+/Calmodulin-Dependent Protein Kinase II: Metabolic and Functional Consequences

The effects of cyclic AMP-dependent protein kinase (cAMP-PK) or Ca2+/calmodulin-dependent protein kinase II (CaMKII) phosphorylation on the binding of bovine tau to tubulin and calpain-mediated degradation of tau were studied. Both cAMP-PK and CaMKII readily phosphorylated tau and slowed the migration of tau on sodium dodecyl sulfate-containing polyacrylamide gels. However, cAMP-PK phosphorylated tau to a significantly greater extent than CaMKII (1.5 and 0.9 mol of 32P/mol of tau, respectively), and phosphorylation of tau by cAMP-PK resulted in a greater shift to a more acidic, less heterogeneous pattern on two-dimensional nonequilibrium pH gradient gels compared with CaMKII phosphorylation. Two-dimensional phosphopeptide maps indicate that cAMP-PK phosphorylates a site or sites on tau that are phosphorylated by CaMKII, as well as a unique site or sites that are not phosphorylated by CaMKII. Phosphorylation of tau by cAMP-PK significantly decreased tubulin binding and, as previously reported, also inhibited the calpain-induced degradation of tau. CaMKII phosphorylation of tau did not alter either of these parameters. These results suggest that the phosphorylation of site(s) on the tau molecule uniquely accessible to cAMP-PK contributed to the decreased tau-tubulin binding and increased resistance to calpain hydrolysis.     

The phosphorylation region of lysine-rich histone in dividing cells

N-Bromosuccinimide cleavage of in vivo ³²P-labelled lysine-rich histone isolated from rapidly dividing cells has been studied. N-Bromosuccinimide cleaves F₁-histone into two fragments, a small N-terminal piece and a larger C-terminal portion. The phosphate-induced microheterogeneity and associated radioactivity which has been linked to cell replication, is found in the carboxyterminal fragment. No phosphorous is found associated with the amino-terminal fragment when histone phosphorylation is associated with cell division. The specific tryptic phosphopeptides obtained from in vivo labelled F₁ are clearly different from those obtained from in vitro incubations of free F₁-histone and cytoplasmic protein kinase.     

The effects of estrogen on cortisol metabolism in female baboons

We examined Cortisol (F) dynamics in female baboons $\text{(Papio anubis)}$ treated with diethylstilbestrol (DES) or estradiol (E₂) and compared values with those previously measured in nonpregnant and pregnant animals. Five regularly menstruating baboons (12–18 kg, BW) were administered 5 mg DES daily via fruit or 0.5 mg E₂/0.1ml oil sc for 30 days. Blood samples, obtained before and after treatment, were assayed for serum F concentrations and serum Cortisol binding capacity (CBC). The metabolic clearance (MCR) and production rate (PR) of F and the catabolism of i.v. administered [³H] F were examined 25 and 30 days after initiation of estrogen treatment. Compared with values in nonpregnant baboons, F metabolism in estrogen treated animals is significantly altered and is characterized by increased formation of unconjugated metabolites, decreased glucuronylation, increased excretion of unconjugated F, cortisone, and highly polar metabolites, and increased CBC. These changes induced by estrogen are similar to those observed in intact pregnant baboons and permit the suggestion that the pattern of F metabolism and the level of CBC in baboon pregnancy are the result of elevated estrogen production.However, estrogen also caused a significant decrease in the MCR and PR of F, parameters which, by contrast, are similar in intact pregnant and nonpregnant baboons. These findings indicate that while estrogen also influences the rate of F clearance and F production, these effects of estrogen are not apparent during pregnancy. Collectively, these findings allow the suggestion that estrogen is a major factor which alters F metabolism and increases serum CBC in baboon gestation. However, additional factors are operative in primate pregnancy which maintain PR and MCR of F at levels similar to those of nonpregnant baboons.     

Herpes Simplex Virus Membrane Proteins gE/gI and US9 Act Cooperatively To Promote Transport of Capsids and Glycoproteins from Neuron Cell Bodies into Initial Axon Segments

Herpes simplex virus (HSV) and other alphaherpesviruses must move from sites of latency in ganglia to peripheral epithelial cells. How HSV navigates in neuronal axons is not well understood. Two HSV membrane proteins, gE/gI and US9, are key to understanding the processes by which viral glycoproteins, unenveloped capsids, and enveloped virions are transported toward axon tips. Whether gE/gI and US9 function to promote the loading of viral proteins onto microtubule motors in neuron cell bodies or to tether viral proteins onto microtubule motors within axons is not clear. One impediment to understanding how HSV gE/gI and US9 function in axonal transport relates to observations that gE⁻, gI⁻, or US9⁻ mutants are not absolutely blocked in axonal transport. Mutants are significantly reduced in numbers of capsids and glycoproteins in distal axons, but there are less extensive effects in proximal axons. We constructed HSV recombinants lacking both gE and US9 that transported no detectable capsids and glycoproteins to distal axons and failed to spread from axon tips to adjacent cells. Live-cell imaging of a gE⁻/US9⁻ double mutant that expressed fluorescent capsids and gB demonstrated >90% diminished capsids and gB in medial axons and no evidence for decreased rates of transport, stalling, or increased retrograde transport. Instead, capsids, gB, and enveloped virions failed to enter proximal axons. We concluded that gE/gI and US9 function in neuron cell bodies, in a cooperative fashion, to promote the loading of HSV capsids and vesicles containing glycoproteins and enveloped virions onto microtubule motors or their transport into proximal axons.