Reactive stepping

During last few decades, oligochitosan (OCS)-coated nanoparticles have received great interest for nanomedicine, food and environment applications. However, their current formulation techniques are time-consuming with multi-synthesis/purification steps and sometimes require the use of organic solvents, crosslinkers and surfactants. Herein, we report a facile and rapid one-pot synthesis of OCS-based nanoparticles using photo-initiated reversible addition fragmentation chain transfer polymerization-induced self-assembly (Photo-RAFT PISA) under UV-irradiation at room temperature...

Analogous to thermal ablation techniques in clinical settings, cell necrosis induced during tumor photothermal therapy (PTT) can provoke an inflammatory response that is detrimental to the treatment of tumors. In this study, we employed a straightforward one-step liquid-phase reduction process to synthesize uniform RhRe nanozymes with an average hydrodynamic size of 41.7 nm for non-inflammatory photothermal therapy. The obtained RhRe nanozymes showed efficient near-infrared (NIR) light absorption for effective PTT, coupled with a remarkable capability to scavenge reactive oxygen species (ROS) for anti-inflammatory treatment...

Preeclampsia is a pregnancy-related disorder manifested as hypertensive pregnancy (HTN-Preg) and often fetal growth restriction (FGR), but the mechanisms involved are unclear. We have reported enhanced reactivity of systemic vessels in HTN-Preg rats, but the critical changes in the uterine circulation are less clear. We tested whether HTN-Preg involves localized aberrations in uterine arterial tone, stiffness and remodeling by matrix metalloproteinases (MMPs). Blood pressure (BP) and litter size were recorded in normal pregnant (Preg) rats and Preg rats with reduced uteroplacental perfusion pressure (RUPP)...

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiologic agent of coronavirus disease 2019 (COVID-19), has posed significant challenges to global health. While much attention has been directed towards understanding the primary mechanisms of SARS-CoV-2 infection, emerging evidence suggests co-infections or superinfections with other viruses may contribute to increased morbidity and mortality, particularly in severe cases of COVID-19. Among viruses that have been reported in patients with SARS-CoV-2, seropositivity for Human cytomegalovirus (HCMV) is associated with increased COVID-19 risk and hospitalization...

Redox signalling is crucial for regulating plant development and adaptation to environmental changes. Proteins with redox-sensitive cysteines can sense oxidative stress and modulate their functions. Recent proteomics efforts have comprehensively mapped the proteins targeted by oxidative modifications. The nucleus, the epicentre of transcriptional reprogramming, contains a large number of proteins that control gene expression. Specific redox-sensitive transcription factors have long been recognised as key players in decoding redox signals in the nucleus and thus in regulating transcriptional responses...

Bone marrow edema (BME) is a frequent MRI finding in patients with knee pain. According to the etiology, BME of the knee can be classified into three main categories: ischemic, mechanic, and reactive. The diagnosis may be difficult, because of the specificity of symptoms and the poor radiographic findings. MRI is the gold standard, showing an area of altered signal of the bone with an high signal intensity on fat-suppressed, T2 weighted images, usually in combination with an intermediate or low signal intensity on T1 weighted images...

INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection represented a disruptive pathology that emerged in late 2019 with profound implications ranging from individual health to health systems and world economy. Our study aimed to evaluate clinical, biochemical and computerized tomography (CT) parameters values in determining the severity of pulmonary embolism (PE) associated with COVID-19. METHODS: We performed an observational cohort study evaluating demographic, clinical, biochemical, coagulation markers, as well as CT imaging parameters...

NADPH oxidases (NOX) are transmembrane proteins, widely spread in eukaryotes and prokaryotes, that produce reactive oxygen species (ROS). Eukaryotes use the ROS products for innate immune defense and signaling in critical (patho)physiological processes. Despite the recent structures of human NOX isoforms, the activation of electron transfer remains incompletely understood. SpNOX, a homolog from Streptococcus pneumoniae , can serves as a robust model for exploring electron transfers in the NOX family thanks to its constitutive activity...

Enzymes are crucial for the emergence and sustenance of life on earth. How they became catalytically active during their evolution is still an open question. Two opposite explanations are plausible: acquiring a mechanism in a series of discrete steps or all at once in a single evolutionary event. Here, we use molecular phylogeny, ancestral sequence reconstruction, and biochemical characterization to follow the evolution of a specialized group of flavoprotein monooxygenases, the bacterial Baeyer-Villiger monooxygenases (BVMOs)...

Di- tert -butyldiphosphatetrahedrane ( t BuCP)2 (1) is a mixed carbon- and phosphorus-based tetrahedral molecule, isolobal to white phosphorus (P4 ). However, despite the fundamental significance and well-explored reactivity of the latter molecule, the precise structure of the free ( t BuCP)2 molecule (1) and a detailed analysis of its electronic properties have remained elusive. Here, single-crystal X-ray structure determination of 1 at low temperature confirms the tetrahedral structure. Furthermore, quantum chemical calculations confirm that 1 is isolobal to P4 and shows a strong largely isotropic diamagnetic response in the magnetic field and thus pronounced spherical aromaticity...

Cancer development and progression are intimately related with post-translational protein modifications, e.g., highly reactive thiol moiety of cysteines enables structural rearrangements resulting in redox biological switches. In this context, redox proteomics techniques, such as 2D redox DIGE, biotin switch assay and OxIcat are fundamental tools to identify and quantify redox-sensitive proteins and to understand redox mechanisms behind thiol modifications. Given the great variability in redox proteomics protocols, problems including decreased resolution of peptides and low protein amounts even after enrichment steps may occur...

Methylation and hydroxymethylation of cytosine moieties in CpG islands of specific genes are epigenetic processes shown to be involved in the development of cervical (pre)neoplastic lesions. We studied global (hydroxy)methylation during the subsequent steps in the carcinogenic process of the uterine cervix by using immunohistochemical protocols for the detection of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in paraffin-embedded tissues of the normal epithelia and (pre)malignant lesions. This approach allowed obtaining spatially resolved information of (epi)genetic alterations for individual cell populations in morphologically heterogeneous tissue samples...

Bioadhesives with all-inclusive properties for simultaneous strong and robust adhesion, cohesion, tracking, drug delivery, self-sterilization, and nontoxicity are still farfetched. Herein, a carbon dot (CD) is made to infuse each of the above-desired aspects with gelatin, an inexpensive edible protein. The CD derived through controlled hydrothermal pyrolysis of dopamine and terephthaldehyde retained -NH2 , -OH, -COOH, and, most importantly, -CHO functionality on the CD surface for efficient skin adhesion and cross-linking...

BACKGROUND: Major Depressive Disorder (MDD) has a complex, bi-directional relationship with metabolic dysfunction, yet the neural correlates of this association are not well understood. METHOD: In this cross-sectional investigation, we employed a two-step 'discovery and confirmatory' strategy, utilizing two independent samples (Sample 1: 288 participants, Sample 2: 196 participants) to examine the association between circulating indicators of metabolic health (leptin and adiponectin) and brain structures in individuals with MDD...

The critical challenge of effectively removing Pb-EDTA complexes and Pb(II) ions from wastewater is pivotal for environmental remediation. This research introduces a cutting-edge bulk-MoS2 /H2 O2 system designed for the simultaneous decomplexation of Pb-EDTA complexes and extraction of free Pb(II) ions, streamlining the process by eliminating the need for subsequent treatment stages. The system exhibits outstanding efficiency, achieving 98.1% decomplexation of Pb-EDTA and 98.6% removal of Pb. Its effectiveness is primarily due to the generation of reactive oxygen species, notably •OH and O2 •- radicals, facilitated by bulk-MoS2 and H2 O2 ...

The speciation of heavy metals in soil is an important factor determining their bioavailability and toxicity, and it is crucial for the scientific assessment of ecological risks posed by heavy metals in soils of typical carbonate areas with high geological background in southwest China. In order to investigate the distribution of speciation of heavy metals in soils of carbonate rock with high geological background, we selected a typical carbonate rock distribution area in Guizhou Province and used the second national soil survey plots as sampling units...

A novel strategy that combines oxidative aminocatalysis and gold catalysis allows the preparation of chiral α-quaternary isochromanes, a motif that is prevalent in natural products and synthetic bioactive compounds. In the first step, α-branched aldehydes and propargylic alcohols are transformed into α-quaternary ethers with excellent optical purities (>90% ee) via oxidative umpolung with DDQ and an amino acid-derived primary amine catalyst. Subsequent gold(I)-catalyzed intramolecular hydroarylation affords the isochromane products with retention of the quaternary stereocenter...

The reactivity of the reduction of NO pre-adsorbed on Rh2-9 + clusters by CO was investigated using a combination of an alternate on-off gas injection method and thermal desorption spectrometry. The reduction of Rh n N x O y + clusters by CO was evaluated by varying the CO concentration at T = 903 K. Among the Rh n N x O x + clusters, the Rh3 N2 O2 + cluster exhibited the highest reduction activity, whereas the other clusters, Rh2,4-9 N x O x + , showed lower reactivity. Density functional theory (DFT) calculations for Rh3 + and Rh6 + revealed that the rate-determining step for NO reduction in the presence of CO was NO bond dissociation through the kinetics analysis using the RRKM theory...

INTRODUCTION: Neonatal calf diarrhea (NCD) is one of the most common diseases in calves, causing huge economic and productivity losses to the bovine industry worldwide. The main pathogens include bovine rotavirus (BRV), bovine coronavirus (BCoV), and Enterotoxigenic Escherichia coli (ETEC) K99. Since multiple infectious agents can be involved in calf diarrhea, detecting each causative agent by traditional methods is laborious and expensive. METHODS: In this study, we developed a one-step multiplex Real-Time PCR assay to simultaneously detect BRV, BCoV, and E...

The Cu-O-Cu core exhibits methane-to-methanol conversion, mirroring the reactivity of the copper-containing enzyme pMMO. Herein, we computationally examined the reactivity of a biomimetic Cu-O-Cu core towards methane-to-methanol conversion. The oxygen atom of the Cu-O-Cu core abstracts hydrogen present in the C-H bond of methane. The spin density at the bridging oxygen helps to abstract hydrogen from the C-H bond. We modulated the spin density of the bridging oxygen by substituting only a single copper atom of the Cu-O-Cu core by metals (M) such as Fe, Co, and Ag...