Executive Dirhodium Synthetic Metalloenzymes with regard to Diazo Direction Cascade Reactions

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Heterogeneous selection is often proposed as a key mechanism maintaining repeatable behavioral variation ("animal personality") in wild populations. Previous studies largely focused on temporal variation in selection within single populations. The relative importance of spatial versus temporal variation remains unexplored, despite these processes having distinct effects on local adaptation. Using data from >3,500 great tits (Parus major) and 35 nest box plots situated within five West-European populations monitored over 4 to 18 y, we show that selection on exploration behavior varies primarily spatially, across populations, and study plots within populations. Exploration was, simultaneously, selectively neutral in the average population and year. These findings imply that spatial variation in selection may represent a primary mechanism maintaining animal personalities, likely promoting the evolution of local adaptation, phenotype-dependent dispersal, and nonrandom settlement. Selection also varied within populations among years, which may counteract local adaptation. Our study underlines the importance of combining multiple spatiotemporal scales in the study of behavioral adaptation.Damage to the microtubule lattice, which serves as a rigid cytoskeletal backbone for the axon, is a hallmark mechanical initiator of pathophysiology after concussion. Understanding the mechanical stress transfer from the brain tissue to the axonal cytoskeleton is essential to determine the microtubule lattice's vulnerability to mechanical injury. Here, we develop an ultrastructural model of the axon's cytoskeletal architecture to identify the components involved in the dynamic load transfer during injury. Corroborative in vivo studies were performed using a gyrencephalic swine model of concussion via single and repetitive head rotational acceleration. Computational analysis of the load transfer mechanism demonstrates that the myelin sheath and the actin/spectrin cortex play a significant role in effectively shielding the microtubules from tissue stress. We derive failure maps in the space spanned by tissue stress and stress rate to identify physiological conditions in which the microtubule lattice can rupture. We establish that a softer axonal cortex leads to a higher susceptibility of the microtubules to failure. Immunohistochemical examination of tissue from the swine model of single and repetitive concussion confirms the presence of postinjury spectrin degradation, with more extensive pathology observed following repetitive injury. Because the degradation of myelin and spectrin occurs over weeks following the first injury, we show that softening of the myelin layer and axonal cortex exposes the microtubules to higher stress during repeated incidences of traumatic brain injuries. Our predictions explain how mechanical injury predisposes axons to exacerbated responses to repeated injuries, as observed in vitro and in vivo.Circadian clocks regulate ∼24-h oscillations in gene expression, behavior, and physiology. While the genetic and molecular mechanisms of circadian rhythms are well characterized, what remains poorly understood are the intracellular dynamics of circadian clock components and how they affect circadian rhythms. Here, we elucidate how spatiotemporal organization and dynamics of core clock proteins and genes affect circadian rhythms in Drosophila clock neurons. Using high-resolution imaging and DNA-fluorescence in situ hybridization techniques, we demonstrate that Drosophila clock proteins (PERIOD and CLOCK) are organized into a few discrete foci at the nuclear envelope during the circadian repression phase and play an important role in the subnuclear localization of core clock genes to control circadian rhythms. Specifically, we show that core clock genes, period and timeless, are positioned close to the nuclear periphery by the PERIOD protein specifically during the repression phase, suggesting that subnuclear localization of core clock genes might play a key role in their rhythmic gene expression. Finally, we show that loss of Lamin B receptor, a nuclear envelope protein, leads to disruption of PER foci and per gene peripheral localization and results in circadian rhythm defects. These results demonstrate that clock proteins play a hitherto unexpected role in the subnuclear reorganization of core clock genes to control circadian rhythms, revealing how clocks function at the subcellular level. Our results further suggest that clock protein foci might regulate dynamic clustering and spatial reorganization of clock-regulated genes over the repression phase to control circadian rhythms in behavior and physiology.With the advent of machine learning and its overarching pervasiveness it is imperative to devise ways to represent large datasets efficiently while distilling intrinsic features necessary for subsequent analysis. The primary workhorse used in data dimensionality reduction and feature extraction has been the matrix singular value decomposition (SVD), which presupposes that data have been arranged in matrix format. A primary goal in this study is to show that high-dimensional datasets are more compressible when treated as tensors (i.e., multiway arrays) and compressed via tensor-SVDs under the tensor-tensor product constructs and its generalizations. We begin by proving Eckart-Young optimality results for families of tensor-SVDs under two different truncation strategies. Since such optimality properties can be proven in both matrix and tensor-based algebras, a fundamental question arises Does the tensor construct subsume the matrix construct in terms of representation efficiency? The answer is positive, as proven by showing that a tensor-tensor representation of an equal dimensional spanning space can be superior to its matrix counterpart. We then use these optimality results to investigate how the compressed representation provided by the truncated tensor SVD is related both theoretically and empirically to its two closest tensor-based analogs, the truncated high-order SVD and the truncated tensor-train SVD.Development of effective vaccines against coronavirus disease 2019 (COVID-19) is a global imperative. Rapid immunization of the entire human population against a widespread, continually evolving, and highly pathogenic virus is an unprecedented challenge, and different vaccine approaches are being pursued. Engineered filamentous bacteriophage (phage) particles have unique potential in vaccine development due to their inherent immunogenicity, genetic plasticity, stability, cost-effectiveness for large-scale production, and proven safety profile in humans. Herein we report the development and initial evaluation of two targeted phage-based vaccination approaches against SARS-CoV-2 dual ligand peptide-targeted phage and adeno-associated virus/phage (AAVP) particles. For peptide-targeted phage, we performed structure-guided antigen design to select six solvent-exposed epitopes of the SARS-CoV-2 spike (S) protein. One of these epitopes displayed on the major capsid protein pVIII of phage induced a specific and sustained humoral response when injected in mice. These phage were further engineered to simultaneously display the peptide CAKSMGDIVC on the minor capsid protein pIII to enable their transport from the lung epithelium into the systemic circulation. Aerosolization of these "dual-display" phage into the lungs of mice generated a systemic and specific antibody response. In the second approach, targeted AAVP particles were engineered to deliver the entire S protein gene under the control of a constitutive CMV promoter. This induced tissue-specific transgene expression, stimulating a systemic S protein-specific antibody response in mice. With these proof-of-concept preclinical experiments, we show that both targeted phage- and AAVP-based particles serve as robust yet versatile platforms that can promptly yield COVID-19 vaccine prototypes for translational development.The COVID-19 pandemic caused by SARS-CoV-2 is an unprecedentedly significant health threat, prompting the need for rapidly developing antiviral drugs for the treatment. Drug repurposing is currently one of the most tangible options for rapidly developing drugs for emerging and reemerging viruses. In general, drug repurposing starts with virtual screening of approved drugs employing various computational methods. However, the actual hit rate of virtual screening is very low, and most of the predicted compounds are false positives. Here, we developed a strategy for virtual screening with much reduced false positives through incorporating predocking filtering based on shape similarity and postdocking filtering based on interaction similarity. We applied this advanced virtual screening approach to repurpose 6,218 approved and clinical trial drugs for COVID-19. All 6,218 compounds were screened against main protease and RNA-dependent RNA polymerase of SARS-CoV-2, resulting in 15 and 23 potential repurposed drugs, respectively. learn more Among them, seven compounds can inhibit SARS-CoV-2 replication in Vero cells. Three of these drugs, emodin, omipalisib, and tipifarnib, show anti-SARS-CoV-2 activities in human lung cells, Calu-3. Notably, the activity of omipalisib is 200-fold higher than that of remdesivir in Calu-3. Furthermore, three drug combinations, omipalisib/remdesivir, tipifarnib/omipalisib, and tipifarnib/remdesivir, show strong synergistic effects in inhibiting SARS-CoV-2. Such drug combination therapy improves antiviral efficacy in SARS-CoV-2 infection and reduces the risk of each drug's toxicity. The drug repurposing strategy reported here will be useful for rapidly developing drugs for treating COVID-19 and other viruses.Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. The ability to predict whether a carcinoma would exhibit invasive ability in patients with PTC is important and has clinical implications for the selection of therapeutic strategies. Although several studies have focused on the genetic characterization of invasive cancer cells, the factors critical to the origination of invasive cancer cells are still unclear. This study aimed to determine whether genomic mutations contribute to the acquisition of the tumor invasion phenotype and to investigate the genetic features of invasive cancer cells in patients with PTC. We performed customized 48-gene deep exon sequencing in samples obtained from 88 patients with PTC via fine needle aspiration; the results revealed that no genetic changes were specifically associated with the tumor aggressiveness phenotype. Our results indicate that genetic mutations do not cause indolent PTCs to become invasive.
To determine if the implementation of a weight-based high-flow nasal cannula (HFNC) protocol for infants with bronchiolitis was associated with improved outcomes, including decreased ICU use.
We implemented a weight-based HFNC protocol across a tertiary care children's hospital and 2 community hospitals that admit pediatric patients on HFNC. We included all patients who were <2 years old and had a discharge diagnosis of bronchiolitis or viral pneumonia during the preimplementation (November 2013 to April 2018) and postimplementation (November 2018 to April 2020) respiratory seasons. Data were analyzed by using an interrupted time series approach. The primary outcome measure was the proportion of patients treated in the ICU. Patients with a complex chronic condition were excluded.
Implementation of the weight-based HFNC protocol was associated with an immediate absolute decrease in ICU use of 4.0%. We also observed a 6.2% per year decrease in the slope of ICU admissions pre- versus postintervention. This was associated with an immediate reduction in median cost per bronchiolitis encounter of $661, a 2.