108 research outputs found

    Downstream Processing Strategies for Lignin-First Biorefinery

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    The lignin-first strategy has emerged as one of the most powerful approaches for generating novel platform chemicals from lignin by efficient depolymerization of native lignin. Because of the emergence of this novel depolymerization method and the definition of viable platform chemicals, future focus will soon shift towards innovative downstream processing strategies. Very recently, many interesting approaches have emerged that describe the production of valuable products across the whole value chain, including bulk and fine chemical building blocks, and several concrete examples have been developed for the production of polymers, pharmaceutically relevant compounds, or fuels. This Minireview provides an overview of these recent advances. After a short summary of catalytic systems for obtaining aromatic monomers, a comprehensive discussion on their separation and applications is given. This Minireview will fill the gap in biorefinery between deriving high yields of lignin monomers and tapping into their potential for making valuable consumer products.</p

    Downstream Processing Strategies for Lignin-First Biorefinery

    Get PDF
    The lignin-first strategy has emerged as one of the most powerful approaches for generating novel platform chemicals from lignin by efficient depolymerization of native lignin. Because of the emergence of this novel depolymerization method and the definition of viable platform chemicals, future focus will soon shift towards innovative downstream processing strategies. Very recently, many interesting approaches have emerged that describe the production of valuable products across the whole value chain, including bulk and fine chemical building blocks, and several concrete examples have been developed for the production of polymers, pharmaceutically relevant compounds, or fuels. This Minireview provides an overview of these recent advances. After a short summary of catalytic systems for obtaining aromatic monomers, a comprehensive discussion on their separation and applications is given. This Minireview will fill the gap in biorefinery between deriving high yields of lignin monomers and tapping into their potential for making valuable consumer products.</p

    1,3-Bis(carboxy­meth­yl)imidazolium triiodide 1-carboxyl­atomethyl-3-carboxy­methyl­imidazolium

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    In the title compound, C7H9N2O4 +·I3 −·C7H8N2O4, the two imidazolium units are hydrogen bonded through the carboxyl groups. The units are further linked via inter­molecular O—H⋯O hydrogen bonding, resulting in a one-dimensional ladder-type structure. As a result, the two carb­oxy groups of each imidazolium unit adopt a cis configuration with respect to the imidazolium ring

    Porous monolith-based magnetism-reinforced in-tube solid phase microextraction of sulfonylurea herbicides in water and soil samples.

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    In the present study, porous monolith-based magnetism-reinforced in-tube solid phase microextraction (MB-MR/IT-SPME) was first introduced to concentrate sulfonylurea herbicides (SUHs). To realize the effective capture of SUHs, a monolithic capillary microextraction column (MCMC) based on poly (vinylimidazole-co-ethylene dimethacrylate) polymer doped with Fe3O4 magnetic nanoparticles was in-situ synthesized in the first step. After that, the MCMC was twined with a magnetic coil which was employed to carry out variable magnetic field during adsorption and desorption procedure. Various important parameters that affecting the extraction performance were inspected in detailed. Results well indicated that exertion of magnetic field in the whole extraction procedure was in favor of the capture and release of the studied SUHs, with the extraction efficiencies increased from 36.8-58.1% to 82.6-94.5%. At the same time, the proposed MB-MR/IT-SPME was online combined to HPLC with diode array detection (HPLC/DAD) to quantify trace levels of SUHs in water and soil samples. The limits of detection (S/N = 3) for water and soil samples were in the ranges of 0.030-0.15 μg/L and 0.30-1.5 μg/kg, respectively. The relative standard deviations (RSDs) for intra- and inter-day variability were both less than 10%. Finally, the introduced approach was successfully applied to monitor the low contents of studied SUHs in environmental water and soil samples. Satisfying fortified recovery and precision were achieved

    Long-term use of antibiotics and risk of type 2 diabetes in women:a prospective cohort study

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    BACKGROUND: Accumulating evidence suggested that long-term antibiotic use may alter the gut microbiome, which has, in turn, been linked to type 2 diabetes. We undertook this study to investigate whether antibiotic use was associated with increased risk of type 2 diabetes. METHODS: This prospective cohort study included women free of diabetes, cardiovascular disease and cancer in the Nurses’ Health Study (NHS 2008–2014) and NHS II (2009–2017). We evaluated the overall duration of antibiotics use in the past 4 years and subsequent diabetes risk with Cox proportional-hazards regression adjusting for demography, family history of diabetes and lifestyle factors. RESULTS: Pooled analyses of NHS and NHS II (2837 cases, 703 934 person-years) revealed that a longer duration of antibiotic use in the past 4 years was associated with higher risk of diabetes [Trend-coefficient = 0.09, 95% confidence interval (CI) 0.04 to 0.13]. Participants who received antibiotics treatment for a medium duration of 15 days to 2 months [hazard ratio (HR) 1.23, 95% CI 1.10 to 1.39] or long duration of >2 months (HR 1.20, 95% CI 1.02 to 1.38) had higher risk of type 2 diabetes as compared with non-users. Subgroup analyses suggested that the associations were unlikely to be modified by age, family history of diabetes, obesity, smoking, alcohol drinking, physical activity and overall diet quality. CONCLUSIONS: A longer duration of antibiotic use in recent years was associated with increased risk of type 2 diabetes in women. Physicians should exercise caution when prescribing antibiotics, particularly for long-term use

    Evaluation of kratom opioid derivatives as potential treatment option for alcohol use disorder

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    Background and Purpose: Mitragyna speciosa extract and kratom alkaloids decrease alcohol consumption in mice at least in part through actions at the δ-opioid receptor (δOR). However, the most potent opioidergic kratom alkaloid, 7-hydroxymitragynine, exhibits rewarding properties and hyperlocomotion presumably due to preferred affinity for the mu opioid receptor (µOR). We hypothesized that opioidergic kratom alkaloids like paynantheine and speciogynine with reduced µOR potency could provide a starting point for developing opioids with an improved therapeutic window to treat alcohol use disorder. Experimental Approach: We characterized paynantheine, speciociliatine, and four novel kratom-derived analogs for their ability to bind and activate δOR, µOR, and κOR. Select opioids were assessed in behavioral assays in male C57BL/6N WT and δOR knockout mice. Key Results: Paynantheine (10 mg∙kg(−1), i.p.) produced aversion in a limited conditioned place preference (CPP) paradigm but did not produce CPP with additional conditioning sessions. Paynantheine did not produce robust antinociception but did block morphine-induced antinociception and hyperlocomotion. Yet, at 10 and 30 mg∙kg(−1) doses (i.p.), paynantheine did not counteract morphine CPP. 7-hydroxypaynantheine and 7-hydroxyspeciogynine displayed potency at δOR but limited µOR potency relative to 7-hydroxymitragynine in vitro, and dose-dependently decreased voluntary alcohol consumption in WT but not δOR in KO mice. 7-hydroxyspeciogynine has a maximally tolerated dose of at least 10 mg∙kg(−1) (s.c.) at which it did not produce significant CPP neither alter general locomotion nor induce noticeable seizures. Conclusion and Implications: Derivatizing kratom alkaloids with the goal of enhancing δOR potency and reducing off-target effects could provide a pathway to develop novel lead compounds to treat alcohol use disorder with an improved therapeutic window

    NOX4 NADPH Oxidase-Dependent Mitochondrial Oxidative Stress in Aging-Associated Cardiovascular Disease

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    Aims: Increased oxidative stress and vascular inflammation are implicated in increased cardiovascular disease (CVD) incidence with age. We and others demonstrated that NOX1/2 NADPH oxidase inhibition, by genetic deletion of p47phox, in Apoe−/− mice decreases vascular reactive oxygen species (ROS) generation and atherosclerosis in young age. The present study examined whether NOX1/2 NADPH oxidases are also pivotal to aging-associated CVD. Results: Both aged (16 months) Apoe−/− and Apoe−/−/p47phox−/− mice had increased atherosclerotic lesion area, aortic stiffness, and systolic dysfunction compared with young (4 months) cohorts. Cellular and mitochondrial ROS (mtROS) levels were significantly higher in aortic wall and vascular smooth muscle cells (VSMCs) from aged wild-type and p47phox−/− mice. VSMCs from aged mice had increased mitochondrial protein oxidation and dysfunction and increased vascular cell adhesion molecule 1 expression, which was abrogated with (2-(2,2,6,6-Tetramethylpiperidin-1-oxyl-4-ylamino)-2-oxoethyl)triphenylphosphonium chloride (MitoTEMPO) treatment. NOX4 expression was increased in the vasculature and mitochondria of aged mice and its suppression with shRNA in VSMCs from aged mice decreased mtROS levels and improved function. Increased mtROS levels were associated with enhanced mitochondrial NOX4 expression in aortic VSMCs from aged subjects, and NOX4 expression levels in arterial wall correlated with age and atherosclerotic severity. Aged Apoe−/− mice treated with MitoTEMPO and 2-(2-chlorophenyl)-4-methyl-5-(pyridin-2-ylmethyl)-1H-pyrazolo[4,3-c]pyridine-3,6(2H,5H)-dione had decreased vascular ROS levels and atherosclerosis and preserved vascular and cardiac function. Innovation and Conclusion: These data suggest that NOX4, but not NOX1/2, and mitochondrial oxidative stress are mediators of CVD in aging under hyperlipidemic conditions. Regulating NOX4 activity/expression and using mitochondrial antioxidants are potential approaches to reducing aging-associated CVD. Antioxid. Redox Signal. 23, 1389–1409

    A novel risk stratification model for STEMI after primary PCI: global longitudinal strain and deep neural network assisted myocardial contrast echocardiography quantitative analysis

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    BackgroundIn ST-segment elevation myocardial infarction (STEMI) with the restoration of TIMI 3 flow by percutaneous coronary intervention (PCI), visually defined microvascular obstruction (MVO) was shown to be the predictor of poor prognosis, but not an ideal risk stratification method. We intend to introduce deep neural network (DNN) assisted myocardial contrast echocardiography (MCE) quantitative analysis and propose a better risk stratification model.Methods194 STEMI patients with successful primary PCI with at least 6 months follow-up were included. MCE was performed within 48 h after PCI. The major adverse cardiovascular events (MACE) were defined as cardiac death, congestive heart failure, reinfarction, stroke, and recurrent angina. The perfusion parameters were derived from a DNN-based myocardial segmentation framework. Three patterns of visual microvascular perfusion (MVP) qualitative analysis: normal, delay, and MVO. Clinical markers and imaging features, including global longitudinal strain (GLS) were analyzed. A calculator for risk was constructed and validated with bootstrap resampling.ResultsThe time-cost for processing 7,403 MCE frames is 773 s. The correlation coefficients of microvascular blood flow (MBF) were 0.99 to 0.97 for intra-observer and inter-observer variability. 38 patients met MACE in 6-month follow-up. We proposed A risk prediction model based on MBF [HR: 0.93 (0.91–0.95)] in culprit lesion areas and GLS [HR: 0.80 (0.73–0.88)]. At the best risk threshold of 40%, the AUC was 0.95 (sensitivity: 0.84, specificity: 0.94), better than visual MVP method (AUC: 0.70, Sensitivity: 0.89, Specificity: 0.40, IDI: −0.49). The Kaplan-Meier curves showed that the proposed risk prediction model allowed for better risk stratification.ConclusionThe MBF + GLS model allowed more accurate risk stratification of STEMI after PCI than visual qualitative analysis. The DNN-assisted MCE quantitative analysis is an objective, efficient and reproducible method to evaluate microvascular perfusion

    Assembly and comparison of two closely related Brassica napus genomes

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    As an increasing number of plant genome sequences become available, it is clear that gene content varies between individuals, and the challenge arises to predict the gene content of a species. However, genome comparison is often confounded by variation in assembly and annotation. Differentiating between true gene absence and variation in assembly or annotation is essential for the accurate identification of conserved and variable genes in a species. Here, we present the de novo assembly of the B. napus cultivar Tapidor and comparison with an improved assembly of the Brassica napus cultivar Darmor-bzh. Both cultivars were annotated using the same method to allow comparison of gene content. We identified genes unique to each cultivar and differentiate these from artefacts due to variation in the assembly and annotation. We demonstrate that using a common annotation pipeline can result in different gene predictions, even for closely related cultivars, and repeat regions which collapse during assembly impact whole genome comparison. After accounting for differences in assembly and annotation, we demonstrate that the genome of Darmor-bzh contains a greater number of genes than the genome of Tapidor. Our results are the first step towards comparison of the true differences between B. napus genomes and highlight the potential sources of error in future production of a B. napus pangenome

    Associations of HLA-DP Variants with Hepatitis B Virus Infection in Southern and Northern Han Chinese Populations: A Multicenter Case-Control Study

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    ) locus has been reported to be associated with hepatitis B virus (HBV) infection in populations of Japan and Thailand. We aimed to examine whether the association can be replicated in Han Chinese populations. = 0.097∼0.697 and 0.198∼0.615 in northern Chinese population, respectively). loci were strongly associated with HBV infection in southern and northern Han Chinese populations, but not with HBV progression
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