Platelet Function Monitoring in Patients With Coronary Artery Disease

Studies focused on patient responsiveness to antiplatelet therapies, particularly aspirin and clopidogrel, have increased in recent years. However, the relations of in vivo platelet function and adverse clinical events to results of ex vivo platelet function tests remain largely unknown. This article describes current methods of measuring platelet function in various clinical and research situations and their advantages and disadvantages, reviews evidence for antiplatelet response variability and resistance, discusses the potential pitfalls of monitoring platelet function, and demonstrates emerging data supporting the positive clinical and treatment implications of platelet function testing

Substantial hepatic necrosis is prognostic in fulminant liver failure

AIM: To evaluate if any association existed between the extent of hepatic necrosis in initial liver biopsies and patient survival. METHODS: Thirty-seven patients with fulminant liver failure, whose liver biopsy exhibited substantial necrosis, were identified and included in the study. The histological and clinical data was then analyzed in order to assess the relationship between the extent of necrosis and patient survival, with and without liver transplantation. The patients were grouped based on the etiology of hepatic necrosis. Each of the etiology groups were then further stratified according to whether or not they had received a liver transplant post-index biopsy, and whether or not the patient survived. RESULTS: The core tissue length ranged from 5 to 44 mm with an average of 23 mm. Causes of necrosis included 14 autoimmune hepatitis, 10 drug induced liver injury (DILI), 9 hepatitis virus infection, and 4 unknown origin. Among them, 11 showed submassive (26%-75% of the parenchymal volume) and 26 massive (76%-100%) necrosis. Transplant-free survival was worse in patients with a higher extent of necrosis (40%, 71.4% and 100% in groups with necrosis of 76%-100%, 51%-75% and 26%-50%, respectively). Additionally, transplant-free survival rates were 66.7%, 57.1%, and 25.0% in groups of autoimmune hepatitis, DILI, and viral hepatitis, respectively. Even after liver transplantation, the survival rate in patients as a result of viral hepatitis remained the lowest (80%, 100%, and 40% in groups of autoimmune hepatitis, DILI, and viral hepatitis, respectively). CONCLUSION: Adequate liver biopsy with more than 75% necrosis is associated with significant transplant-free mortality that is critical in predicting survival

Neutrino masses in the Lepton Number Violating MSSM

We consider the most general supersymmetric model with minimal particle content and an additional discrete Z_3 symmetry (instead of R-parity), which allows lepton number violating terms and results in non-zero Majorana neutrino masses. We investigate whether the currently measured values for lepton masses and mixing can be reproduced. We set up a framework in which Lagrangian parameters can be initialised without recourse to assumptions concerning trilinear or bilinear superpotential terms, CP-conservation or intergenerational mixing and analyse in detail the one loop corrections to the neutrino masses. We present scenarios in which the experimental data are reproduced and show the effect varying lepton number violating couplings has on the predicted atmospheric and solar mass^2 differences. We find that with bilinear lepton number violating couplings in the superpotential of the order 1 MeV the atmospheric mass scale can be reproduced. Certain trilinear superpotential couplings, usually, of the order of the electron Yukawa coupling can give rise to either atmospheric or solar mass scales and bilinear supersymmetry breaking terms of the order 0.1 GeV^2 can set the solar mass scale. Further details of our calculation, Lagrangian, Feynman rules and relevant generic loop diagrams, are presented in three Appendices.Comment: 48 pages, 7 figures, v2 references added, typos corrected, published versio

Reproduction of Twentieth Century Intradecadal to Multidecadal Surface Temperature Variability in Radiatively Forced Coupled Climate Models

[1] Coupled Model Intercomparison Project 3 simulations that included time-varying radiative forcings were ranked according to their ability to consistently reproduce twentieth century intradecadal to multidecadal (IMD) surface temperature variability at the 5° by 5° spatial scale. IMD variability was identified using the running Mann-Whitney Z method. Model rankings were given context by comparing the IMD variability in preindustrial control runs to observations and by contrasting the IMD variability among the ensemble members within each model. These experiments confirmed that the inclusion of time-varying external forcings brought simulations into closer agreement with observations. Additionally, they illustrated that the magnitude of unforced variability differed between models. This led to a supplementary metric that assessed model ability to reproduce observations while accounting for each model\u27s own degree of unforced variability. These two metrics revealed that discernable differences in skill exist between models and that none of the models reproduced observations at their theoretical optimum level. Overall, these results demonstrate a methodology for assessing coupled models relative to each other within a multimodel framework

A Mammalian Target of Rapamycin-Perilipin 3 (mTORC1-Plin3) Pathway is essential to Activate Lipophagy and Protects Against Hepatosteatosis

[Background and Aims] NAFLD is the most common hepatic pathology in western countries and no treatment is currently available. NAFLD is characterized by the aberrant hepatocellular accumulation of fatty acids in the form of lipid droplets (LDs). Recently, it was shown that liver LD degradation occurs through a process termed lipophagy, a form of autophagy. However, the molecular mechanisms governing liver lipophagy are elusive. Here, we aimed to ascertain the key molecular players that regulate hepatic lipophagy and their importance in NAFLD.[Approach and Results] We analyzed the formation and degradation of LD in vitro (fibroblasts and primary mouse hepatocytes), in vivo and ex vivo (mouse and human liver slices) and focused on the role of the autophagy master regulator mammalian target of rapamycin complex (mTORC) 1 and the LD coating protein perilipin (Plin) 3 in these processes. We show that the autophagy machinery is recruited to the LD on hepatic overload of oleic acid in all experimental settings. This led to activation of lipophagy, a process that was abolished by Plin3 knockdown using RNA interference. Furthermore, Plin3 directly interacted with the autophagy proteins focal adhesion interaction protein 200 KDa and autophagy-related 16L, suggesting that Plin3 functions as a docking protein or is involved in autophagosome formation to activate lipophagy. Finally, we show that mTORC1 phosphorylated Plin3 to promote LD degradation.[Conclusions] These results reveal that mTORC1 regulates liver lipophagy through a mechanism dependent on Plin3 phosphorylation. We propose that stimulating this pathway can enhance lipophagy in hepatocytes to help protect the liver from lipid-mediated toxicity, thus offering a therapeutic strategy in NAFLD.Supported by C0120R3166, C0245R4032, and BH182173 from Newcastle University. M. G.-M. is a Sara Borrell Postdoctoral fellow (CD18/00203) from the Ministerio de Ciencia, Innovación y Universidades (Spain). J. P. B. is funded by the Agencia Estatal de Investigación, grants PID2019-105699RB-I00/AEI/10.13039/501100011033 and RED2018-102576-T, Instituto de Salud Carlos III (CB16/10/00282), Junta de Castilla y León (Escalera de Excelencia CLU-2017-03), Ayudas Equipos Investigación Biomedicina 2017 Fundación BBVA, and Fundación Ramón Areces. V. I. K. acknowledges support from Biotechnology and Biological Sciences Research Council (BB/M023389/1, BB/R008167/1, BBPeer reviewe

The forebrain synaptic transcriptome is organized by clocks but its proteome is driven by sleep

Neurons have adapted mechanisms to traffic RNA and protein into distant dendritic and axonal arbors. Taking a biochemical approach, we reveal that forebrain synaptic transcript accumulation shows overwhelmingly daily rhythms, with two-thirds of synaptic transcripts showing time-of-day-dependent abundance independent of oscillations in the soma. These transcripts formed two sharp temporal and functional clusters, with transcripts preceding dawn related to metabolism and translation and those anticipating dusk related to synaptic transmission. Characterization of the synaptic proteome around the clock demonstrates the functional relevance of temporal gating for synaptic processes and energy homeostasis. Unexpectedly, sleep deprivation completely abolished proteome but not transcript oscillations. Altogether, the emerging picture is one of a circadian anticipation of messenger RNA needs in the synapse followed by translation as demanded by sleep-wake cycles

HIV-1 subtype C Nef-mediated SERINC5 down-regulation significantly contributes to overall Nef activity

BACKGROUND: Nef performs multiple cellular activities that enhance HIV-1 pathogenesis. The role of Nef-mediated down-regulation of the host restriction factor SERINC5 in HIV-1 pathogenesis is not well-defined. We aimed to investigate if SERINC5 down-regulation activity contributes to HIV-1 subtype C disease progression, to assess the relative contribution of this activity to overall Nef function, and to identify amino acids required for optimal activity. We measured the SERINC5 down-regulation activity of 106 subtype C Nef clones, isolated from individuals in early infection, for which the Nef activities of CD4 and HLA-I down-regulation as well as alteration of TCR signalling were previously measured. The relationship between SERINC5 down-regulation and markers of disease progression, and the relative contribution of SERINC5 down-regulation to a Nef fitness model-derived E value (a proxy for overall Nef fitness in vivo), were assessed. RESULTS: No overall relationship was found between SERINC5 down-regulation and viral load set point (p = 0.28) or rate of CD4+ T cell decline (p = 0.45). CD4 down-regulation (p = 0.02) and SERINC5 down-regulation (p = 0.003) were significant determinants of E values in univariate analyses, with the greatest relative contribution for SERINC5 down-regulation, and only SERINC5 down-regulation remained significant in the multivariate analysis (p = 0.003). Using a codon-by-codon analysis, several amino acids were significantly associated with increased (10I, 11V, 38D, 51T, 65D, 101V, 188H and, 191H) or decreased (10K, 38E, 65E, 135F, 173T, 176T and, 191R) SERINC5 down-regulation activity. Site-directed mutagenesis experiments of selected mutants confirmed a substantial reduction in SERINC5 down-regulation activity associated with the mutation 173T, while mutations 10K, 135F, and 176T were associated with more modest reductions in activity that were not statistically significant. CONCLUSIONS: These results suggest that SERINC5 down-regulation is a significant contributor to overall Nef function and identify potential genetic determinants of this Nef function that may have relevance for vaccines or therapeutics

The c-Rel Subunit of NF-κB Regulates Epidermal Homeostasis and Promotes Skin Fibrosis in Mice

The five subunits of transcription factor NF-κB have distinct biological functions. NF-κB signaling is important for skin homeostasis and aging, but the contribution of individual subunits to normal skin biology and disease is unclear. Immunohistochemical analysis of the p50 and c-Rel subunits within lesional psoriatic and systemic sclerosis skin revealed abnormal epidermal expression patterns, compared with healthy skin, but RelA distribution was unaltered. The skin of Nfkb1−/− and c-Rel−/− mice is structurally normal, but epidermal thickness and proliferation are significantly reduced, compared with wild-type mice. We show that the primary defect in both Nfkb1−/− and c-Rel−/− mice is within keratinocytes that display reduced proliferation both in vitro and in vivo. However, both genotypes can respond to proliferative stress, with 12-O-tetradecanoylphorbol-13-acetate–induced epidermal hyperproliferation and closure rates of full-thickness skin wounds being equivalent to those of wild-type controls. In a model of bleomycin-induced skin fibrosis, Nfkb1−/− and c-Rel−/− mice displayed opposite phenotypes, with c-Rel−/− mice being protected and Nfkb1−/− developing more fibrosis than wild-type mice. Taken together, our data reveal a role for p50 and c-Rel in regulating epidermal proliferation and homeostasis and a profibrogenic role for c-Rel in the skin, and identify a link between epidermal c-Rel expression and systemic sclerosis. Modulating the actions of these subunits could be beneficial for treating hyperproliferative or fibrogenic diseases of the skin

Urinary Retention Evaluation and Catheterization Algorithm for Adult Inpatients

Importance: Acute urinary retention (UR) is common, yet variations in diagnosis and management can lead to inappropriate catheterization and harm. Objective: To develop an algorithm for screening and management of UR among adult inpatients. Design, Setting, and Participants: In this mixed-methods study using the RAND/UCLA Appropriateness Method and qualitative interviews, an 11-member multidisciplinary expert panel of nurses and physicians from across the US used a formal multi-round process from March to May 2015 to rate 107 clinical scenarios involving diagnosis and management of adult UR in postoperative and medical inpatients. The panel ratings informed the first algorithm draft. Semistructured interviews were conducted from October 2020 to May 2021 with 33 frontline clinicians—nurses and surgeons from 5 Michigan hospitals—to gather feedback and inform algorithm refinements. Main Outcomes and Measures: Panelists categorized scenarios assessing when to use bladder scanners, catheterization at various scanned bladder volumes, and choice of catheterization modalities as appropriate, inappropriate, or uncertain. Next, qualitative methods were used to understand the perceived need, usability, and potential algorithm uses. Results: The 11-member expert panel (10 men and 1 woman) used the RAND/UCLA Appropriateness Method to develop a UR algorithm including the following: (1) bladder scanners were preferred over catheterization for UR diagnosis in symptomatic patients or starting as soon as 3 hours since last void if asymptomatic, (2) bladder scanner volumes appropriate to prompt catheterization were 300 mL or greater in symptomatic patients and 500 mL or greater in asymptomatic patients, and (3) intermittent was preferred to indwelling catheterization for managing lower bladder volumes. Interview findings were organized into 3 domains (perceived need, feedback on algorithm, and implementation suggestions). The 33 frontline clinicians (9 men and 24 women) who reviewed the algorithm reported that an evidence-based protocol (1) was needed and could be helpful to clinicians, (2) should be simple and graphically appealing to improve rapid clinician review, and (3) should be integrated within the electronic medical record and prominently displayed in hospital units to increase awareness. The draft algorithm was iteratively refined based on stakeholder feedback. Conclusions and Relevance: In this study using a systematic, multidisciplinary, evidence- and expert opinion–based approach, a UR evaluation and catheterization algorithm was developed to improve patient safety by increasing appropriate use of bladder scanners and catheterization. This algorithm addresses the need for practical guidance to manage UR among adult inpatients.</p

Sleep-wake cycles drive daily dynamics of synaptic phosphorylation

The circadian clock drives daily changes of physiology, including sleep-wake cycles, through regulation of transcription, protein abundance, and function. Circadian phosphorylation controls cellular processes in peripheral organs, but little is known about its role in brain function and synaptic activity. We applied advanced quantitative phosphoproteomics to mouse forebrain synaptoneurosomes isolated across 24 hours, accurately quantifying almost 8000 phosphopeptides. Half of the synaptic phosphoproteins, including numerous kinases, had large-amplitude rhythms peaking at rest-activity and activity-rest transitions. Bioinformatic analyses revealed global temporal control of synaptic function through phosphorylation, including synaptic transmission, cytoskeleton reorganization, and excitatory/inhibitory balance. Sleep deprivation abolished 98% of all phosphorylation cycles in synaptoneurosomes, indicating that sleep-wake cycles rather than circadian signals are main drivers of synaptic phosphorylation, responding to both sleep and wake pressures