First use of a divalent lanthanide for visible-light-promoted photoredox catalysis

We report the first catalytic use of a divalent lanthanide in visible-light-promoted bond-forming reactions. Our new precatalyst uses europium in the +2 oxidation state and is active in the presence of blue light from light-emitting diodes. The use of low-energy visible light reduces the occurrence of potential side reactions that might be induced by higher-energy UV light. The system described here uses zinc metal as a sacrificial reductant and is tolerant to wet, protic solvents. The catalyst can be made in situ from relatively inexpensive and air-stable EuCl3·6H2O, and the ligand can be synthesized in large quantities in two steps. With 0.5% loading of precatalyst, an average of 120 turnovers was observed in six hours for reductive coupling of benzyl chloride. We expect that the results will initiate the study of visible-light-promoted photoredox catalysis using divalent europium in a variety of reactions.

A health status survey of clams, Mya arenaria and Ensis siliqua, in the Irish Sea

The soft shell clam, Mya arenaria, and the razor clam, Ensis siliqua, are widely distributed in Irish waters. Though the reproductive biology and other aspects of the physiology of these species has been previously investigated, little or no data are currently available on their health status. As this knowledge is essential for correct management of a species, M. arenaria and E. siliqua were examined to assess their current health status using histological and molecular methods, over a period of sixteen months. No pathogens or disease were observed in M. arenaria, and low incidences of Prokaryote inclusions, trematode parasites, Nematopsis spp. and eosinophilic bodies were recorded in razor clams for the first time in Northern European waters.

High-throughput vector-borne disease environmental surveillance by polymerase chain reaction according to international accreditation requirements

Although vector-borne diseases are specific to the region of the host, there is a necessity for surveillance or reference laboratories to perform standardized, high-throughput testing capable of meeting the needs of a changing military environment and response efforts. The development of standardized, high-throughput, semiquantitative real-time and reverse transcription real-time polymerase chain reaction (PCR) methods allows for the timely dissemination of data to interested parties while providing a platform in which long-term sample storage is possible for the testing of new pathogens of interest using a historical perspective. PCR testing allows for the analysis of multiple pathogens from the same sample, thus reducing the workload of entomologists in the field and increasing the ability to determine if a pathogen has spread beyond traditionally defined locations. US Army Public Health Command Region-Europe (USAPHCR-Europe) Laboratory Sciences (LS) has standardized tests for 9 pathogens at multiple life stages. All tests are currently under international accreditation standards. Using these PCR methods and laboratory model, which have universal Department of Defense application, the USAPHCR-Europe LS will generate quality data that is scientifically sound and legally defensible to support force health protection for the US military in both deployed and garrison environments.

Student-Athletes and Gambling: An Analysis of Attitudes Towards Risk-Taking

Gambling scandals at Arizona State University, Boston College, and Northwestern University have made gambling prevention a point of emphasis in the NCAA and throughout colleges and universities across the nation. Despite this emphasis, there is minimal research at any level regarding gambling and student-athletes. This research examines attitudinal differences towards risk-taking among student-athletes who gamble on college sports and those who indicate no such gambling activity. Our findings indicate that student-athletes who gambled were more likely to have attitudes supportive of risk taking behavior than their student-athlete peers who did not gamble.

alpha(1A) adrenergic receptor induces eukaryotic initiation factor 4E-binding protein 1 phosphorylation via a Ca(2+)-dependent pathway independent of phosphatidylinositol 3-kinase/Akt

Phosphorylation of the translation repressor eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) is thought to be partly responsible for increased protein synthesis induced by growth factors. This study investigated the effect of a G(q)-coupled receptor on protein synthesis and the phosphorylation state and function of 4E-BP1 in Rat-1 fibroblasts expressing the human alpha(1A) adrenergic receptor. Treatment of cells with phenylephrine (PE), a specific alpha(1) adrenergic receptor agonist, increased protein synthesis and induced the phosphorylation of 4E-BP1 and its release from translation initiation factor 4E. Although the PE-induced phosphorylation of 4E-BP1 was blocked by the phosphatidylinositol 3-kinase inhibitor LY294002, neither phosphatidylinositol 3-kinase nor Akt, its downstream effector, is activated in cells treated with PE (Ballou, L. M., Cross, M. E., Huang, S., McReynolds, E. M., Zhang, B. X., and Lin, R. Z., J. Biol. Chem. 275, 4803-4809). The effect of PE on 4E-BP1 phosphorylation was also abolished in cells depleted of intracellular Ca(2+) and in cells pretreated with calmodulin antagonists. By contrast, phosphorylation of 4E-BP1 still occurred in cells in which the Ca(2+)- and diacylglycerol-dependent isoforms of protein kinase C were down-regulated by prolonged exposure to a phorbol ester. We conclude that activation of the alpha(1A) adrenergic receptor in Rat-1 fibroblasts leads to phosphorylation of 4E-BP1 via a pathway that is Ca(2+)- and calmodulin-dependent. Phosphatidylinositol 3-kinase, Akt, and phorbol ester-sensitive protein kinase C isoforms do not appear to be required in this signaling pathway.

Differential regulation of the phosphatidylinositol 3-kinase/Akt and p70 S6 kinase pathways by the alpha(1A)-adrenergic receptor in rat-1 fibroblasts

Phosphatidylinositol (PI) 3-kinase and its downstream effector Akt are thought to be signaling intermediates that link cell surface receptors to p70 S6 kinase. We examined the effect of a G(q)-coupled receptor on PI 3-kinase/Akt signaling and p70 S6 kinase activation using Rat-1 fibroblasts stably expressing the human alpha(1A)-adrenergic receptor. Treatment of the cells with phenylephrine, a specific alpha(1)-adrenergic receptor agonist, activated p70 S6 kinase but did not activate PI 3-kinase or any of the three known isoforms of Akt. Furthermore, phenylephrine blocked the insulin-like growth factor-I (IGF-I)-induced activation of PI 3-kinase and the phosphorylation and activation of Akt-1. The effect of phenylephrine was not confined to signaling pathways that include insulin receptor substrate-1, as the alpha(1)-adrenergic receptor agonist also inhibited the platelet-derived growth factor-induced activation of PI 3-kinase and Akt-1. Although increasing the intracellular Ca(2+) concentration with the ionophore A23187 inhibited the activation of Akt-1 by IGF-I, Ca(2+) does not appear to play a role in the phenylephrine-mediated inhibition of the PI 3-kinase/Akt pathway. The differential ability of phenylephrine and IGF-I to activate Akt-1 resulted in a differential ability to protect cells from UV-induced apoptosis. These results demonstrate that activation of p70 S6 kinase by the alpha(1A)-adrenergic receptor in Rat-1 fibroblasts occurs in the absence of PI 3-kinase/Akt signaling. Furthermore, this receptor negatively regulates the PI 3-kinase/Akt pathway, resulting in enhanced cell death following apoptotic insult.

Changes in nuclear protein during the cell cycle in cultured mast cells separated by zonal centrifugation

1. Exponentially grown mouse mast cells (cell line P815, strain Y) were separated by zonal centrifugation on a Ficoll gradient. Fractions were allocated to different phases of the cell cycle according to the specific radioactivity of their DNA. 2. Histones were extracted and their thiol content was analysed. The proportion of reduced thiol increased in S phase, decreasing subsequently. 3. The phosphate content of histone F1 and of the other histones reached a peak in early and later S phase respectively. The incorporation of (32)P into these fractions showed a corresponding increase. 4. The timing of histone synthesis was examined. Incorporation of (14)C-labelled amino acids into the histone fractions took place at the same times as phosphorylation. 5. Acid nuclear proteins differ from the histones in incorporating labelled amino acids and (32)P fairly constantly through the cell cycle.

Changes in histone phosphorylation and associated early metabolic events in pig lymphocyte cultures transformed by phytohaemagglutinin or 6-N,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate

1. Pig lymphocytes were transformed by dibutyryl cyclic AMP (6-N,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate) at concentrations of 0.01-0.1mum. The pattern of incorporation of label from [5-(3)H]uridine and [6-(3)H]thymidine into RNA and DNA respectively was identical with that obtained with unpurified phytohaemagglutinin. 2. Chlorpromazine (0.1mum) prevented the stimulation of [5-(3)H]uridine incorporation into RNA by phytohaemagglutinin, but only slightly lowered the lymphocyte response to dibutyryl cyclic AMP. 3. An increase in the size and specific radioactivity of the intracellular P(i) pool was found immediately after stimulation by both phytohaemagglutinin and dibutyryl cyclic AMP. This was followed after some 30min by a rise in the specific radioactivity and concentration of ATP. 4. There was an immediate increase in the specific radioactivity of phosphate groups of histones; by about 45min after stimulation only the histones remaining after extraction of histone fraction F1 continued to incorporate (32)P from [(32)P]P(i). 5. Histone kinase activity increased in the first 30min after stimulation; subsequently histone F1 kinase activity decreased, but activity with the other histones as substrate continued to increase for a further 30min. Kinase activation was effected by cyclic AMP (adenosine 3':5'-cyclic monophosphate). 6. Histone phosphatase activity behaved similarly to that of the kinase.