Facial paralysis is an infrequent and serious potential complication of acute otitis media (AOM). We describe a pediatric case of rapidly progressive facial paralysis as a secondary complication alongside AOM, caused by the non-typeable (NTHi) strain, which was managed with facial nerve decompression, glucocorticoid medication, and antimicrobial chemotherapy. The reasons why NTHi becomes pathogenic in certain patients are not yet fully understood, and the specific interactions and adaptations that lead to complications must be further investigated, as they result in more complex treatment approaches.
View Article and Find Full Text PDFThe endometrium is a dynamic tissue that undergoes significant changes during the reproductive cycle and pregnancy. Its high regenerative capacity is due to the presence of progenitor cells, which maintain tissue homeostasis. Previous studies have identified small populations of endometrial progenitor cells and investigated their role in tissue repair.
View Article and Find Full Text PDFA novel molecular structure that bridges the fields of molecular optical cycling and molecular photoswitching is presented. It is based on a photoswitching molecule azobenzene functionalized with one and two CaO- groups, which can act as optical cycling centers (OCCs). This paper characterizes the electronic structure of the resulting model systems, focusing on three questions: (1) how the electronic states of the photoswitch are impacted by a functionalization with an OCC; (2) how the states of the OCC are impacted by the scaffold of the photoswitch; and (3) whether the OCC can serve as a spectroscopic probe of isomerization.
View Article and Find Full Text PDFAfter nearly 50 years of searching, the vacuum ultraviolet Th nuclear isomeric transition has recently been directly laser excited and measured with high spectroscopic precision. Nuclear clocks based on this transition are expected to be more robust than and may outperform current optical atomic clocks. These clocks also promise sensitive tests for new physics beyond the standard model.
View Article and Find Full Text PDFRestructuring of surfaces and interfaces plays a key role in the activation and/or deactivation of a wide spectrum of heterogeneous catalysts and functional materials. The statistical ensemble representation can provide unique atomistic insights into this fluxional and metastable realm, but constructing the ensemble is very challenging, especially for the systems with off-stoichiometric reconstruction and varying coverage of mixed adsorbates. Here, we report GOCIA, a versatile global optimizer for exploring the chemical space of these systems.
View Article and Find Full Text PDFAlzheimer's disease (AD) has long proven to be a complex neurodegenerative disorder, with cholinergic dysfunction, oxidative stress, and neuroinflammation being just a few of its pathological features. The complexity of the disease requires a multitargeted treatment covering its many aspects. In the present investigation, an arylhydrazone derivative of 5-methoxyindole-2-carboxylic acid (5MeO), with in vitro strong antioxidant, neuroprotective and monoamine oxidase B-inhibiting effects, was studied in a scopolamine-induced Alzheimer-type dementia in rats.
View Article and Find Full Text PDFgroup B , GBS) is an important human and animal pathogen. In recent years, the number of streptococcal isolates resistant to antimicrobial agents has increased in many parts of the world. Various mechanisms of antimicrobial resistance and capsular serotypes of GBS with different geographical distributions can be found.
View Article and Find Full Text PDFBy hydrogenating carbon dioxide to value-added products such as methanol, heterogeneous catalysts can lower greenhouse gas emissions and generate alternative liquid fuels. The most common commercial catalyst for the reduction of CO to methanol is Cu/ZnO/AlO, where ZnO improves conversion and selectivity toward methanol. The structure of this catalyst is thought to be Zn oxy(hydroxyl) overlayers on the nanometer scale on Cu.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2024
It is broadly recognized that intramolecular electric fields, produced by the protein scaffold and acting on the active site, facilitate enzymatic catalysis. This field effect can be described by several theoretical models, each of which is intuitive to varying degrees. In this contribution, we show that a fundamental effect of electric fields is to generate electrostatic potentials that facilitate the energetic alignment of reactant frontier orbitals.
View Article and Find Full Text PDFWe introduce a machine learning framework designed to predict enzyme functionality directly from the heterogeneous electric fields inherent to protein active sites. We apply this method to a curated data set of heme-iron oxidoreductases, spanning three enzyme classes: monooxygenases, peroxidases, and catalases. Conventional analysis, focused on simplistic, point electric fields along the Fe-O bond, is shown to be inadequate for accurate activity prediction.
View Article and Find Full Text PDFhas been recognized as an important cause of upper respiratory tract and middle ear infections in children, as well as chronic obstructive pulmonary disease and chronic bronchitis in adults. We aim to study the clonal structure, antimicrobial resistance, and serotypes of strains recovered from patients of different ages. Nasopharyngeal swabs, middle ear fluid, and sputum samples were collected.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2024
Utilizing molecular dynamics and free energy perturbation, we examine the relative binding affinity of several covalent polycyclic aromatic hydrocarbon - DNA (PAH-DNA) adducts at the central adenine of NRAS codon-61, a mutational hotspot implicated in cancer risk. Several PAHs classified by the International Agency for Research on Cancer as probable, possible, or unclassifiable as to carcinogenicity are found to have greater binding affinity than the known carcinogen, benzo[a]pyrene (B[a]P). van der Waals interactions between the intercalated PAH and neighboring nucleobases, and minimal disruption of the DNA duplex drive increases in binding affinity.
View Article and Find Full Text PDFAchieving ultranarrow absorption linewidths in the condensed phase enables optical state preparation of specific non-thermal states, a prerequisite for quantum-enabled technologies. The 4f orbitals of lanthanide(iii) complexes are often referred to as "atom-like," reflecting their isolated nature, and are promising substrates for the optical preparation of specific quantum states. To better understand the photophysical properties of 4f states and assess their potential for quantum applications, theoretical building blocks are required for rapid screening.
View Article and Find Full Text PDFThe energetic disorder induced by fluctuating liquid environments acts in opposition to the precise control required for coherence-based sensing. Overcoming fluctuations requires a protected quantum subspace that only weakly interacts with the local environment. We report a ytterbium complex that exhibited an ultranarrow absorption linewidth in solution at room temperature with a full width at half maximum of 0.
View Article and Find Full Text PDFExperiments and theory are combined to search for catalyst activity and stability descriptors for the direct reactive capture and conversion (RCC) of CO in ammonia capture solutions using Cu, Ag, Au, Sn, and Ti electrodes. Two major phenomena emerge in RCC that are not predominant in the electrochemical CO reduction (COR) reaction, namely, the rapid corrosion and restructuring of the catalyst in the presence of the CO-ammonia adducts and the promotion of the competing hydrogen evolution reaction (HER). The prevalence of HER in RCC is correlated to the electrostatic attraction of the protonated amine to the electrode and the repulsion of the captured CO, using the potential of zero charge (PZC).
View Article and Find Full Text PDFLiSrAlF_{6} crystals doped with ^{229}Th are used in a laser-based search for the nuclear isomeric transition. Two spectroscopic features near the nuclear transition energy are observed. The first is a broad excitation feature that produces redshifted fluorescence that decays with a timescale of a few seconds.
View Article and Find Full Text PDFObjective: The carotid stiffness is an important factor in the pathogenesis of cerebrovascular small vessel disease. Our study aimed to evaluate the relation of the local arterial stiffness of the common carotid artery (CCA) to the hemodynamic forces and blood viscosity in patients with cerebral lacunar infarctions (LI).
Methods: Twenty-two patients with chronic LI and 15 age-matched controls were examined.
To unravel why computational design fails in creating viable enzymes, while directed evolution (DE) succeeds, our research delves into the laboratory evolution of protoglobin. DE has adapted this protein to efficiently catalyze carbene transfer reactions. We show that the previously proposed enhanced substrate access and binding alone cannot account for increased yields during DE.
View Article and Find Full Text PDFThe dynamic restructuring of Cu has been observed under electrochemical conditions, and it has been hypothesized to underlie the unique reactivity of Cu toward CO electroreduction. Roughening is one of the key surface phenomena for Cu activation, whereby numerous atomic vacancies and adatoms form. However, the atomic structure of such surface motifs in the presence of relevant adsorbates has remained elusive.
View Article and Find Full Text PDFThe covalent interaction of N-heterocyclic carbenes (NHCs) with transition metal atoms gives rise to distinctive frontier molecular orbitals (FMOs). These emergent electronic states have spurred the widespread adoption of NHC ligands in chemical catalysis and functional materials. Although formation of carbene-metal complexes in self-assembled monolayers on surfaces has been explored, design and electronic structure characterization of extended low-dimensional NHC-metal lattices remains elusive.
View Article and Find Full Text PDFMolecules cooled to ultracold temperatures are desirable for applications in fundamental physics and quantum information science. However, cooling polyatomic molecules with more than six atoms has not yet been achieved. Building on the idea of an optical cycling center (OCC), a moiety supporting a set of localized and isolated electronic states within a polyatomic molecule, molecules with two OCCs (bi-OCCs) may afford better cooling efficiency by doubling the photon scattering rate.
View Article and Find Full Text PDFis a Gram-negative facultative anaerobic bacterium that is a typical commensal of the oral cavity and enteric tract of domestic animals. Human infections caused by this species are most often associated with dog bites and rarely with other animal bites. In this report, we present a case of a 34-year-old man who developed soft tissue infection of the left hand after a cat bite.
View Article and Find Full Text PDFThis paper focuses on the creation of an in vitro collection of grapevine hybrids from the breeding program of the Kazakh Scientific Research Institute of Fruit Growing and Viticulture and investigates the presence of resistance mediated by and loci. We looked at the optimization of in vitro establishment using either shoots taken directly from field-grown plants or from budwood cuttings forced indoors. We further screened for the presence of endophyte contamination in the initiated explants and optimized the multiplication stage.
View Article and Find Full Text PDF, (GAS), and (GBS) are bacteria that can cause a range of infections, some of them life-threatening. This review examines the spread of antibiotic resistance and its mechanisms against antibiotics for streptococcal infections. Data on high-level penicillin-resistant invasive pneumococci have been found in Brazil (42.
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