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Heteroatom-participated lignin depolymerization for heterocyclic aromatic compounds production is of great importance to expanding the product portfolio and meeting value-added biorefinery demand, but it is also particularly challenging. In this work, the synthesis of pyrimidines from lignin β-O-4 model compounds, the most abundant segment in lignin, mediated by NaOH through a one-pot multi-component cascade reaction is reported. Mechanism study suggests that the transformation starts by NaOH-induced deprotonation of Cα-H bond in β-O-4 model compounds, and involves highly coupled sequential cleavage of C-O bonds, alcohol dehydrogenation, aldol condensation, and dehydrogenative aromatization. This strategy features transition-metal free catalysis, a sustainable universal approach, no need of external oxidant/reductant, and an efficient one-pot process, thus providing an unprecedented opportunity for N-containing aromatic heterocyclic compounds synthesis from biorenewable feedstock. With this protocol, an important marine alkaloid meridianin derivative can be synthesized, emphasizing the application feasibility in pharmaceutical synthesis. Lignin depolymerization to make heterocyclic aromatic compounds is of great importance to expanding the product portfolio derived from biomass, but it is also particularly challenging. In this work, the authors report pyrimidine synthesis from lignin β-O-4 model compounds via a one-pot multicomponent cascade reaction.

One-pot synthesis of heterocyclic aromatics with good optical properties from phenolic β-O-4 lignin segments is of high importance to meet high value added biorefinery demands. However, executing this process remains a huge challenge due to the incompatible reaction conditions of the depolymerization of lignin β-O-4 segments containing γ-OH functionalities and bioresource-based aggregation-induced emission luminogens (BioAIEgens) formation with the desired properties. In this work, benzannulation reactions starting from lignin β-O-4 moieties with 3-alkenylated indoles catalyzed by vanadium-based complexes have been successfully developed, affording a wide range of functionalized carbazoles with up to 92% yield. Experiments and density functional theory calculations suggest that the reaction pathway involves the selective cleavage of double C-O bonds/Diels-Alder cycloaddition/dehydrogenative aromatization. Photophysical investigations show that these carbazole products represent a class of BioAIEgens with twisted intramolecular charge transfer. Distinctions of emission behavior were revealed based on unique acceptor-donor-acceptor-type molecular conformations as well as molecular packings. This work features lignin β-O-4 motifs with γ-OH functionalities as renewable substrates, without the need to apply external oxidant/reductant systems. Here, we show a concise and sustainable route to functional carbazoles with AIE properties, building a bridge between lignin and BioAIE materials. Biorenewable feedstocks are important for developing more sustainable materials, but developing processes can be challenging due to incompatible reaction conditions. Here, the authors report the one-pot preparation of aggregation-induced emission luminogens from lignin moieties.

Declining grip strength is an indicator of cognitive loss in older individuals but it has not been explored people younger than 65 years old. The purpose of this study was to investigate the relationship between grip strength and specific cognitive tests known to decline with mild cognitive impairment in young and middle-aged adults. Declines in cognitive performance in middle-aged adults may provide evidence that these changes occur earlier than previously reported. A cross sectional design was used to compare differences between young and middle-aged healthy adults and to investigate associations between cognitive and grip strength measures within groups. Healthy young (20-30 years old) and middle-aged (45-65 years old) adults completed five cognitive tests including the Stroop, California Verbal Learning Test, Symbol Digit Modalities Test, Trail Making Tests and the Controlled Oral Word Association Test. All participants completed right and left maximum grip strength measures. Middle-aged adults performed significantly worse on right and left grip strength and the Stroop test (p<0.05) when compared to the younger group. There were no significant relationships among grip strength and cognitive performance at the whole-group level or within the younger-age group; however, weaker grip strength was significantly associated with poorer Controlled Oral Word Association Test total cluster (r = 0.458; p < .05) and Stroop interference (r = 0.471; p < .05) scores in the middle-aged group. Findings from this study suggest that cognitive changes may occur earlier than previously thought (prior to age 65). Weaker grip strength was significantly associated with poorer function in two of the cognitive measures in the middle-age group, suggesting that some domains of cognition, specifically semantic categorization and executive function, may be particularly sensitive to age-related changes.

Multiple sclerosis (MS) is a chronic neurodegenerative disease characterized by mobility impairments that limit physical activity and reduce quality of life. While traditional clinical measures and participant-reported outcomes provide valuable insights, they often fall short of fully capturing the complexities of real-world mobility. This study evaluates the predictive value of combining sensor-derived clinical measures and participant-reported outcomes to better forecast prospective physical activity levels in individuals with MS. Forty-six participants with MS completed surveys assessing fatigue, concern about falling, and perceived walking ability (MSWS-12), alongside sensor-based assessments of gait and balance. Over three months, participants wore Fitbit devices to monitor physical activity, including step counts and total activity levels. Forward stepwise regression revealed that a combined model of participant-reported outcomes and sensor-derived measures explained the most variance in future physical activity, with MSWS-12 and backward walking velocity emerging as key predictors. These findings highlight the importance of integrating subjective and objective measures to provide a more comprehensive understanding of physical activity patterns in MS. This approach supports the development of personalized interventions aimed at improving mobility, increasing physical activity, and enhancing overall quality of life for individuals with MS.

Chronological age incompletely captures neurodegenerative burden and functional vulnerability in multiple sclerosis (MS). Brain-predicted age difference (Brain-PAD; predicted minus chronological age) provides an MRI-derived index of accelerated brain aging, but links to mobility and real-world behavior remain unclear. Forty-three adults with MS completed structural MRI, mobility testing, and six months of free-living physical activity monitoring. Brain age was estimated using PyBrainAge applied to FreeSurfer-derived cortical thickness and subcortical volumes. Hierarchical regressions tested whether Brain-PAD explained additional variance in mobility (Mini-BESTest total and subscores; forward/backward walking velocity) and moderate-to-vigorous physical activity (MVPA) beyond age and disability (PDDS). Predicted brain age exceeded chronological age (Brain-PAD = 8.4 ± 11.1 years; p < 0.001). After accounting for age and PDDS, Brain-PAD explained additional variance in Mini-BESTest total (ΔR2 = 0.05, p = 0.042) and anticipatory control (ΔR2 = 0.08, p = 0.034), with a trend for sensory orientation. Brain-PAD was not associated with walking velocity beyond PDDS. Higher Brain-PAD was associated with lower MVPA (β = −0.91, p = 0.005) and explained additional variance (ΔR2 = 0.19). Brain-PAD is elevated in MS and relates to balance control and real-world physical activity beyond age and disability, highlighting its potential to identify functional vulnerability.

Artificial aggregation‐induced emission luminogens (AIEgens) have flourished in bio‐applications with the development of synthetic chemistry, which however are plagued by issues like singularity in structures and non‐renewability. The unique structures and renewability of biomass moieties can compensate for these drawbacks, but their properties are hard to design and regulate due to their confined structures. Therefore, it appears to be a reasonable approach to derive AIEgens from abundant biomass (BioAIEgens), integrating the bilateral advantages of both synthetic and natural AIEgens. In this work, the blue‐violet emissive coumarin with its lactone structure serving as a rare natural acceptor, is utilized to construct donor‐π‐acceptor typed BioAIE isomers incorporating the propeller‐like and electron‐donating triphenylamine (TPA) unit. The results show that Cm‐p‐TPA undergoes charge transfer with its keto form, emitting red light at 600 nm, which can be applied to monitor Cu2+ concentration during mitophagy using fluorescence lifetime imaging microscopy because of the excellent biocompatibility, photostability, and specific recognition to Cu2+. This work not only demonstrates the feasibility of utilizing positional isomerization to modulate excited‐state evolutions and resultant optical properties, but also provides evidence for the rationality of constructing biologically‐active BioAIEgens via a biomass‐derivatization concept. This work not only demonstrates the feasibility of utilizing positional isomerization to modulate excited‐state evolutions and produce a red‐emissive BioAIEgen to be applied to monitor the Cu2+ concentration in live cells using FLIM, but also provides evidence for the rationality of constructing biologically‐active BioAIEgens via a biomass‐derivatization concept.

Alzheimer's disease (AD) is a common neurodegenerative condition involving a complex blend of disturbances in synaptic development and maintenance, neurovascular cross-talk, ionic and nutrient transport, and mitochondrial metabolism. The precise molecular profile of AD onset with insight for major pathological contributors remains unclear with corresponding impedances in therapeutic development. The current study sought two objectives, as (i) to resolve the molecular pathogenesis from cognitive impairment to the onset of AD-like neuropathology and (ii) whether the novel agent cannabidiol (CBD), noted for its neuroprotective effects, influences the molecular transition associated with AD onset. Dietary CBD was administered daily (80-100 mg/kg/day) in male mice and wild-type B6129SF2/J animals from 4.5 to 6.5 mo of age with inclusion of vehicle controls. RNA sequencing encompassed longitudinal and cross-sectional blood and brain samples, respectively. Metabolomics and behavioral analyses examined brain regions (cortex, hippocampus) and associated integrated neurocircuitry. There were >1,000 differentially expressed markers of AD onset, whereby >75% were either eliminated or reversed in the direction of expression in response to CBD. Signaling pathways encompassed synaptic development and plasticity (e.g., Foxp2), neurovascular interactions (Smad9, Angptl6), receptors and ion channels (Gria4, Chrna2, Rgs7/Rgs7bp), mitochondrial genes (Ndufa7, Cox7a2), immunity (Ncr1), oxidation-reduction (Esr1), lipid synthesis (Fasn, ApoE), and carbohydrate metabolism (Mafa, Mlxipl). As potentially addressable with CBD treatment, AD onset represents molecular integration of neurovascular interactions, channelopathies, metabolic disturbances, and aberrations in developmental genes with involvement of major pathological contributors such as inflammation, oxidative signaling, dyslipidemia, and insulin resistance.

The development of non-precious, acid-stable, oxygen reduction reaction (ORR) electrocatalysts can significantly aid the commercialization of proton exchange membrane fuel cells (PEMFCs). We report a survey of the ORR electrocatalysis on 3d metal substituted (M = Mn, Fe, Co) molybdenum and tungsten nitrides in acidic environments. We find that molybdate catalysts are more active than tungstates, with the specific activity depending on the chemistry of the substituted 3d metal. In both families, more electronegative 3d metals led to higher ORR activity (i.e., Co > Fe > Mn). We attribute this result to the ability of the more electronegative 3d metal to withdraw electrons from the Mo- or W-based active sites, effectively oxidizing the metal centers of the catalysts. Based on our observation, future nitride ORR electrocatalysts can be further optimized by oxidizing the Mo sites further by, for example, adding even more electronegative dopant metals or incorporating anion vacancies.

Background In Colombia, recent legislation regarding end-of-life decisions includes palliative sedation, advance directives and euthanasia. We analysed which aspects influence health professionals´ decisions regarding end-of-life medical decisions and care for cancer patients. Methods Qualitative descriptive–exploratory study based on phenomenology using semi-structured interviews. We interviewed 28 oncologists, palliative care specialists, general practitioners and nurses from three major Colombian institutions, all involved in end-of-life care of cancer patients: Hospital Universitario San Ignacio and Instituto Nacional de Cancerología in Bogotá and Hospital Universitario San José in Popayan. Results When making decisions regarding end-of-life care, professionals consider: 1. Patient’s clinical condition, cultural and social context, in particular treating indigenous patients requires special skills. 2. Professional skills and expertise: training in palliative care and experience in discussing end-of-life options and fear of legal consequences. Physicians indicate that many patients deny their imminent death which hampers shared decision-making and conversations. They mention frequent ambiguity regarding who initiates conversations regarding end-of-life decisions with patients and who finally takes decisions. Patients rarely initiate such conversations and the professionals normally do not ask patients directly for their preferences. Fear of confrontation with family members and lawsuits leads healthcare workers to carry out interventions such as initiating artificial feeding techniques and cardiopulmonary resuscitation, even in the absence of expected benefits. The opinions regarding the acceptability of palliative sedation, euthanasia and use of medications to accelerate death without the patients´ explicit request vary greatly. 3. Conditions of the insurance system: limitations exist in the offer of oncology and palliative care services for important proportions of the Colombian population. Colombians have access to opioid medications, barriers to their application are largely in delivery by the health system, the requirement of trained personnel for intravenous administration and ambulatory and home care plans which in Colombia are rare. Conclusions To improve end-of-life decision making, Colombian healthcare workers and patients need to openly discuss wishes, needs and care options and prepare caregivers. Promotion of palliative care education and development of palliative care centres and home care plans is necessary to facilitate access to end-of-life care. Patients and caregivers’ perspectives are needed to complement physicians’ perceptions and practices.