Flp-recombinase mouse line for genetic manipulation of ipRGCs.

Light has myriad impacts on behavior, health, and physiology. These signals originate in the retina and are relayed to the brain by more than 40 types of retinal ganglion cells (RGCs). Despite a growing appreciation for the diversity of RGCs, how these diverse channels of light information are ultimately integrated by the ~50 retinorecipient brain targets to drive these light-evoked effects is a major open question. This gap in understanding primarily stems from a lack of genetic tools that specifically label, manipulate, or ablate specific RGC types. Here, we report the generation and characterization of a new mouse line (Opn4FlpO), in which FlpO is expressed from the Opn4 locus, to manipulate the melanopsin-expressing, intrinsically photosensitive retinal ganglion cells. We find that the Opn4FlpO line, when crossed to multiple reporters, drives expression that is confined to ipRGCs and primarily labels the M1-M3 subtypes. Labeled cells in this mouse line show the expected intrinsic, melanopsin-based light response and morphological features consistent with the M1-M3 subtypes. In alignment with the morphological and physiological findings, we see strong innervation of non-image forming brain targets by ipRGC axons, and weaker innervation of image forming targets in Opn4FlpO mice labeled using AAV-based and FlpO-reporter lines. Consistent with the FlpO insertion disrupting the endogenous Opn4 transcript, we find that Opn4FlpO/FlpO mice show deficits in the pupillary light reflex, demonstrating their utility for behavioral research in future experiments. Overall, the Opn4FlpO mouse line drives Flp-recombinase expression that is confined to ipRGCs and most effectively drives recombination in M1-M3 ipRGCs. This mouse line will be of broad use to those interested in manipulating ipRGCs through a Flp-based recombinase for intersectional studies or in combination with other, non-Opn4 Cre driver lines.

Author Correction: Inhibition of casein kinase 1δ/εimproves cognitive-affective behavior and reduces amyloid load in the APP-PS1 mouse model of Alzheimer's disease.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Inhibition of casein kinase 1δ/εimproves cognitive-affective behavior and reduces amyloid load in the APP-PS1 mouse model of Alzheimer's disease.

Circadian rhythm disruption is one of the earliest biomarkers of Alzheimer's disease (AD), and there exists a bidirectional relationship by which dysfunctions in the circadian clock drive AD pathology and AD pathology drives circadian dysfunction. Casein kinase 1 (CK1) isoforms ε and δ, key circadian regulators, are significantly upregulated in AD and may contribute to AD pathogenesis. In the current studies, we have examined how inhibition of CK1ε/δ with PF-670462 (at 10 mg/kg, δ isoform selective, or 30 mg/kg, δ and ε selective) impacts regional Aß and circadian gene expression in 10-13 month old APP-PS1 mice and nontransgenic controls. We have also assessed circadian, cognitive, and affective behavioral correlates of these neural changes. At baseline, APP-PS1 mice showed a short period, as well as impaired cognitive performance in both prefrontal cortex and hippocampus-dependent tasks. Both doses of PF-670462 lengthened the period and improved affect, whereas only the higher dose improved cognition. Further, PF-670462 treatment produced a dose-dependent reduction in amyloid burden - overall Aß signal decreased in all three areas; in the prefrontal cortex and hippocampus, PF-670462 also reduced plaque size. Together, these findings support chronotherapy as a potential tool to improve behavior in AD.

Dizziness, driving, and the Driver and Vehicle Licensing Agency: audit of advice given to patients, and design of a patient information leaflet.

BACKGROUND: Evidence from the literature shows that clinicians' knowledge of rules and legislation surrounding driving can often be poor. A closed-loop audit was conducted to gauge the level of driving advice given to patients with dizziness. METHODS: The clinical notes of 100 patients referred to the vertigo clinic at a tertiary referral centre were retrospectively searched for evidence of driving advice. Education sessions were undertaken and a patient information leaflet was developed before a second cycle of the audit. RESULTS AND CONCLUSION: The proportion of patients having documented evidence of receiving driving advice increased from 6.3 per cent to 10.4 per cent. It is therefore clear that, despite this improvement, a significant proportion of patients' notes did not contain documentation about driving. This is likely because of many reasons, including individual interpretation by clinicians. This paper provides a reminder of the rules, and discusses their interpretation and implementation in an increasingly medicolegal environment.

Projecting Changes in Expected Annual Damages From Riverine Flooding in the United States.

Inland flood risk in the United States is most often conveyed through maps of 1% annual exceedance probability (AEP) or "100-year" floodplains. However, monetary damages from flooding arise from a full distribution of events, including floods both larger and smaller than the 1% AEP event. Furthermore, floodplains are not static, since both the frequency and magnitude of flooding are likely to change in a warming climate. We explored the implications of a changing frequency and magnitude of flooding across a wide spectrum of flood events, using a sample of 376 watersheds in the United States where floodplains from multiple recurrence intervals have been mapped. Using an inventory of assets within these mapped floodplains, we first calculated expected annual damages (EADs) from flooding in each watershed under baseline climate conditions. We find that the EAD is typically a factor of 5-7 higher than the expected damages from 100-year events alone and that much of these damages are attributable to floods smaller than the 1% AEP event. The EAD from flooding typically increases by 25-50% under a 1 °C warming scenario and in most regions more than double under a 3 °C warming scenario. Further increases in EAD are not as pronounced beyond 3 °C warming, suggesting that most of the projected increases in flood damages will have already occurred, for most regions of the country, by that time. Adaptations that protect against today's 100-year flood will have increasing benefits in a warmer climate by also protecting against more frequent, smaller events.

Portrayal of waterpipe (shisha, hookah, nargile) smoking on Twitter: a qualitative exploration.

OBJECTIVES: To describe and characterize social media content in relation to waterpipe smoking using qualitative methods. STUDY DESIGN: Exploratory qualitative design. METHODS: A representative sample of pre-existing social media content from Twitter relating to waterpipe smoking and written in the English language was collected during a 1 week period in July 2014. A total of 9671 tweets were collected; duplicates and retweets were removed leaving 4439 unique tweets. Data were analyzed semiotically (positive, negative, positive and negative, no sentiment, unclassifiable) and thematically. Photographs attached to tweets written by individual users indexed using #hookah (n = 299) were subjected to content analysis. RESULTS: Over half of all tweets were positive about waterpipe smoking (59%), with 3% negative, 21% lacking sentiment and 17% unclassifiable. However, there were variations by likely author of tweet, with 91% of tweets from individual users classified as positive. Twitter users focused on their emotional experience, location, other products they were consuming alongside waterpipe smoking, and who they were with. Analysis of photographs highlighted a high degree of synergy between text and visual representations of waterpipe smoking, and two thirds of photographs contained at least part of a waterpipe. CONCLUSIONS: Waterpipe smoking may be normalized as an enjoyable activity in this online environment, posing a challenge for public health.

Extracellular proteolysis of reelin by tissue plasminogen activator following synaptic potentiation.

The secreted glycoprotein reelin plays an indispensable role in neuronal migration during development and in regulating adult synaptic functions. The upstream mechanisms responsible for initiating and regulating the duration and magnitude of reelin signaling are largely unknown. Here we report that reelin is cleaved between EGF-like repeats 6-7 (R6-7) by tissue plasminogen activator (tPA) under cell-free conditions. No changes were detected in the level of reelin and its fragments in the brains of tPA knockouts, implying that other unknown proteases are responsible for generating reelin fragments found constitutively in the adult brain. Induction of NMDAR-independent long-term potentiation with the potassium channel blocker tetraethylammonium chloride (TEA-Cl) led to a specific up-regulation of reelin processing at R6-7 in wild-type mice. In contrast, no changes in reelin expression and processing were observed in tPA knockouts following TEA-Cl treatment. These results demonstrate that synaptic potentiation results in tPA-dependent reelin processing and suggest that extracellular proteolysis of reelin may regulate reelin signaling in the adult brain.

Treatment options for the menopausal woman.

Hormone replacement therapy (HRT) is not benign; its adverse effects can be as serious as the health threats it was designed to prevent. An element of trial and error exists when tailoring a patient treatment regimen. Lack of clinician knowledge and poor clinician-patient communication can result in incorrect or suboptimal HRT decisions. This article presents a comprehensive assessment of options for women entering menopause; recent epidemiologic findings and various HRTs are discussed.

Augmented hydrolysis of diisopropyl fluorophosphate in engineered mutants of phosphotriesterase.

The phosphotriesterase from Pseudomonas diminuta hydrolyzes a wide variety of organophosphate insecticides and acetylcholinesterase inhibitors. The rate of hydrolysis depends on the substrate and can range from 6000 s-1 for paraoxon to 0.03 s-1 for the slower substrates such as diethylphenylphosphate. Increases in the reactivity of phosphotriesterase toward the slower substrates were attempted by the placement of a potential proton donor group at the active site. Distances from active site residues in the wild type protein to a bound substrate analog were measured, and Trp131, Phe132, and Phe306 were found to be located within 5.0 A of the oxygen atom of the leaving group. Eleven mutants were created using site-directed mutagenesis and purified to homogeneity. Phe132 and Phe306 were replaced by tyrosine and/or histidine to generate all combinations of single and double mutants at these two sites. The single mutants W131K, F306K, and F306E were also constructed. Kinetic constants were measured for all of the mutants with the substrates paraoxon, diethylphenylphosphate, acephate, and diisopropylfluorophosphate. Vmax values for the mutant enzymes with the substrate paraoxon varied from near wild type values to a 4-order of magnitude decrease for the W131K mutant. There were significant increases in the Km for paraoxon for all mutants except F132H. Vmax values measured using diethylphenylphosphate decreased for all mutants except for F132H and F132Y, whereas Km values ranged from near wild type levels to increases of 25-fold. Vmax values for acephate hydrolysis ranged from near wild type values to a 10(3)-fold decrease for W131K. Km values for acephate ranged from near wild type to a 5-fold increase. Vmax values for the mutants tested with the substrate diisopropylfluorophosphate showed an increase in all cases except for the W131K, F306K, and F306E mutants. The Vmax value for the F132H/F306H mutant was increased to 3100 s-1. These studies demonstrated for the first time that it is possible to significantly enhance the ability of the native phosphotriesterase to hydrolyze phosphorus-fluorine bonds at rates that rival the hydrolysis of paraoxon.

Phenytoin-induced chronic hepatitis.

Phenytoin has been associated with acute hepatotoxicity. Chronic liver enzyme abnormalities associated with phenytoin have been attributed to enzyme induction. There have been no reports of phenytoin-induced chronic hepatitis. We describe an asymptomatic 52-year-old woman who received phenytoin sodium for 11 years and was found to have elevated serum aminotransferases. Assays for hepatitis A, B, and C were negative. Liver biopsy was performed and showed chronic persistent hepatitis. This documentation of phenytoin-induced chronic persistent hepatitis was proven by histology and its etiology confirmed by drug withdrawal and by rechallenge. Although uncommon, this entity is important to recognize in the differential diagnosis of asymptomatic chronic hepatic enzyme dysfunction.