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Transuranic actinide reactions with simple gas-phase molecules.
The intent of this research is to conduct an experimental study of f-element chemistry fo r the purpose of identifying reaction trends and mechanisms of the early actinide metals with simple gas phase molecules . Previous research has elucidated some of the fundamenta l chemistry of the 4f elements,1-5 however, more complex chemistry is expected for the 5f serie s due to the inclusion of the 5f electrons in the valence shell . The matrix isolation approach, which is well-suited to the experimental study of transient species, will be used for sample collection, and IR/NIR/VIS spectroscopy will be employed to interrogate deposited matrices . The strength of this method lies in the use of isotopes of reactants, which permits the identification of guest molecules in a noble gas matrix by observation of vibrational frequenc y shifts and patterns upon isotopic substitution . Using this technique at the University of Virginia, the first noble gas-actinide bond has recently been identified, a weak U-Ar bond on the CUO molecule.6 Uranium has similarly been observed to bond to krypton and xenon, whereas thoriu m and the lanthanides have not exhibited this activity . It is expected that plutonium will be even more reactive in this respect . We will extend the body of actinide experimental evidence t o include the transuranic elements neptunium, plutonium, and americium reacted with isotopes o f oxygen, nitrogen, hydrogen, carbon monoxide, and carbon dioxide
WNT activates the AAK1 kinase to promote clathrin-mediated endocytosis of LRP6 and establish a negative feedback loop
beta-Catenin-dependent WNT signal transduction governs development, tissue homeostasis, and a vast array of human diseases. Signal propagation through a WNT-Frizzled/LRP receptor complex requires proteins necessary for clathrin-mediated endocytosis (CME). Paradoxically, CME also negatively regulates WNT signaling through internalization and degradation of the receptor complex. Here, using a gain-of-function screen of the human kinome, we report that the AP2 associated kinase 1 (AAK1), a known CME enhancer, inhibits WNT signaling. Reciprocally, AAK1 genetic silencing or its pharmacological inhibition using a potent and selective inhibitor activates WNT signaling. Mechanistically, we show that AAK1 promotes clearance of LRP6 from the plasma membrane to suppress the WNT pathway. Time-course experiments support a transcription-uncoupled, WNT-driven negative feedback loop; prolonged WNT treatment drives AAK1-dependent phosphorylation of AP2M1, clathrin-coated pit maturation, and endocytosis of LRP6. We propose that, following WNT receptor activation, increased AAK1 function and CME limits WNT signaling longevity2617993FUNDAĂĂO DE AMPARO Ă PESQUISA DO ESTADO DE SĂO PAULO - FAPESP2013/50724-5; 2016/17469-0M.B.M. acknowledges support from the NIH (RO1-CA187799 and U24-DK116204-01). M.J.A. received financial support from NIH T32 Predoctoral Training Grants in Pharmacology (T32-GM007040-43 and T32-GM007040-42), an Initiative for Maximizing Student Diversity Grant (R25-GM055336-16), and the NIH National Cancer Institute (NCI) NRSA Predoctoral Fellowship to Promote Diversity in Health-Related Research (F31CA228289). M.P.W. received support from the Lymphoma Research Foundation (337444) and the NIH (T32-CA009156-35). Y.N. was supported by grants-in-aid from the Japan Society for the Promotion of Science (JSPS) (15KK0356 and 16K11493). T.T. was supported by the Howard Hughes Medical Institute Gilliam Fellowship for Advanced Study. M.V.G. was supported by Cancer Research UK (grants C7379/A15291 and C7379/A24639 to Mariann Bienz). The UNC Flow Cytometry Core Facility is supported in part by Cancer Center Core Support Grant P30 CA016086 to the UNC Lineberger Comprehensive Cancer Center, and research reported in this publication was supported by the Center for AIDS Research (award number 5P30AI050410), and the content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. The Structural Genomics Consortium (SGC) is a registered charity (number 1097737) that receives funds from AbbVie, Bayer Pharma AG, Boehringer Ingelheim, the Canada Foundation for Innovation, the Eshelman Institute for Innovation, Genome Canada, the Innovative Medicines Initiative (European Union [EU]/European Federation of Pharmaceutical Industries and Associations [EFPIA]) (ULTRA-DD grant no. 115766), Janssen, Merck & Company, Merck KGaA, Novartis Pharma AG, the Ontario Ministry of Economic Development and Innovation, Pfizer, the SĂŁo Paulo Research Foundation (FAPESP) (2013/50724-5), Takeda, and the Wellcome Trust (106169/ZZ14/Z). R.R.R. received financial support from FAPESP (2016/17469-0). We would also like to thank Claire Strain-Damerell and Pavel Savitsky for cloning various mutants of AAK1 and BMP2K proteins that were used in the crystallization trials. Additionally, we thank Dr. Sean Conner for providing the AAK1 plasmids, Dr. Stephane Angers for kindly providing the HEK293T DVL TKO cells, and Dr. Mariann Bienz for providing comments and feedback. We would like to thank members of the Major laboratory for their feedback and expertise regarding experimental design and project directio
Using Grizzly Bears to Assess Harvest-Ecosystem Tradeoffs in Salmon Fisheries
Using grizzly bears as surrogates for âsalmon ecosystemâ function, the authors develop a generalizable ecosystem-based management framework that enables decision-makers to quantify ecosystem-harvest tradeoffs between wild and human recipients of natural resources like fish
Expression of PPARÎŽ in multistage carcinogenesis of the colorectum: implications of malignant cancer morphology
Whether peroxisome proliferator-activated receptor (PPAR) ÎŽ is a good target for the chemoprevention and/or treatment of colorectal cancer (CRC) remains controversial. Our goal was to examine PPARÎŽ expression in multistage carcinogenesis of the colorectum and to assess the relevance of PPARÎŽ in CRC. Immunohistochemical analysis indicated that PPARÎŽ expression increased from normal mucosa to adenomatous polyps to CRC. In cancer tissues, the PPARÎŽ protein was accumulated only in those cancer cells with highly malignant morphology, as represented by a large-sized nucleus, round-shaped nucleus, and presence of clear nucleoli. Interestingly, the cancer tissue often contained both PPARÎŽ-positive and -negative areas, each retaining their respective specific morphological features. Moreover, this pattern persisted even when PPARÎŽ-positive and -negative cells were aligned next to each other within a single cancer nest or gland and was present in the majority of CRC cases. Immunohistochemistry for Ki-67 proliferation marker showed no significant correlation between Ki-67 and PPARÎŽ in CRC samples. Based on Western blot analysis and quantitative RTâPCR, high PPARÎŽ protein expression correlated with high PPARÎŽ mRNA levels. Peroxisome proliferator-activated receptor ÎŽ may have a supporting role in tumorigenesis, and the close association between PPARÎŽ expression and malignant morphology of CRC cells suggests a pivotal role in cancer tissue
Genetic mechanisms of critical illness in COVID-19.
Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, PÂ =Â 1.65Â ĂÂ 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, PÂ =Â 2.3Â ĂÂ 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, PÂ =Â 3.98Â ĂÂ Â 10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, PÂ =Â 4.99Â ĂÂ 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice
The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy
Background: The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations.
Methods: Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (>â90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves.
Results: After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45â85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations >â90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SEâ=â0.013, pââ90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score.
Conclusion: The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care
Progress towards a public chemogenomic set for protein kinases and a call for contributions
Protein kinases are highly tractable targets for drug discovery. However, the biological function and therapeutic potential of the majority of the 500+ human protein kinases remains unknown. We have developed physical and virtual collections of small molecule inhibitors, which we call chemogenomic sets, that are designed to inhibit the catalytic function of almost half the human protein kinases. In this manuscript we share our progress towards generation of a comprehensive kinase chemogenomic set (KCGS), release kinome profiling data of a large inhibitor set (Published Kinase Inhibitor Set 2 (PKIS2)), and outline a process through which the community can openly collaborate to create a KCGS that probes the full complement of human protein kinases
Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial
Background
Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects.
Methods
FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762.
Findings
Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839â1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26â6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38â2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months.
Interpretation
Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function.
Funding
UK Stroke Association and NIHR Health Technology Assessment Programme
Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19
IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19.
Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19.
DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 nonâcritically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022).
INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (nâ=â257), ARB (nâ=â248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; nâ=â10), or no RAS inhibitor (control; nâ=â264) for up to 10 days.
MAIN OUTCOMES AND MEASURES The primary outcome was organ supportâfree days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes.
RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ supportâfree days among critically ill patients was 10 (â1 to 16) in the ACE inhibitor group (nâ=â231), 8 (â1 to 17) in the ARB group (nâ=â217), and 12 (0 to 17) in the control group (nâ=â231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ supportâfree days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively).
CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes.
TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570