In Europe, considerable amounts of bark are available from wood‐processing industries such as forestry and timber production. Polyphenolic components can be collected by hot water extraction. The extracted compounds can then be applied as colorants in textile dyeing operations. In this study, a comparative assessment of four different tree species with regard to their colouristic potential for wool dyeing was performed. Aqueous extracts from alder, ash tree, spruce and oak bark were prepared and analysed for their total phenolic content and ultraviolet (UV) absorption at 360–370 nm. The extracts were used for meta‐mordant dyeing by adding iron sulphate mordant (FeSO4 × 7H2O). For comparison, iron salt‐based dye lakes were prepared and used in dyeing experiments. For each tree species, a specific correlation between the total phenolic content of the dyebath and the colour depth in terms of K/S and CIELab coordinates was observed, both for the aqueous extracts and the dye lakes. Based on this relationship, standardisation and quality control of raw materials and dye lakes can be installed as important stages in the industrialisation of natural colorants from bark. The preparation of concentrated dye lakes permits formation of a concentrated colorant as dye product, which then can be standardised and delivered to textile dyehouses, similar to synthetic dyes. The preparation of dye lakes offers a relevant route towards achieving the commercialisation of bark extracts as natural colorants. 相似文献
3,3′‐Diindolylmethanes (DIMs) are an important class of indole alkaloids that exhibit anti‐inflammatory and anti‐cancer effects. Herein, we report on a new, mild and efficient copper(II)‐promoted decarboxylative coupling reaction of 2‐(1H‐indol‐3‐yl)acetic acid derivatives ( 1 a – h ) with a variety of (substituted) indoles ( 2 a – t ) yielding (un)symmetrically substituted DIMs ( 3 a – z , 3 aa – ai ). Reaction of 2‐(1H‐indol‐3‐yl)acetic acid ( 1 a ) with 7‐azaindole led to the 3,3′‐connected DIM analog 5 d , while 4‐, 5‐, and 6‐azaindoles and benzimidazole reacted at the N1‐nitrogen atom. Reaction of 1 a with 1H‐indazoles led to a mixture of 1‐ and 2‐substituted indazole derivatives. The new method allows large‐scale synthesis of biologically active DIMs.
Naturally occurring compounds represent a vast pool of pharmacologically active entities. One of such compounds is andrographolide, which is endowed with many beneficial properties, including the activity against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). To initiate a drug repurposing or hit optimization campaign, it is imperative to unravel the primary mechanism(s) of the antiviral action of andrographolide. Here, we showed by means of a reporter gene assay that andrographolide exerts its anti-SARS-CoV-2 effects by inhibiting the interaction between Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor erythroid 2-related factor 2 (NRF2) causing NRF2 upregulation. Moreover, we demonstrated that subtle structural modifications of andrographolide could lead to derivatives with stronger on-target activities and improved physicochemical properties. Our results indicate that further optimization of this structural class is warranted to develop novel COVID-19 therapies. 相似文献
The prospective, multicenter TESTBREAST study was initiated with the aim of identifying a novel panel of blood-based protein biomarkers to enable early breast cancer detection for moderate-to-high-risk women. Serum samples were collected every (half) year up until diagnosis. Protein levels were longitudinally measured to determine intrapatient and interpatient variabilities. To this end, protein cluster patterns were evaluated to form a conceptual basis for further clinical analyses. Using a mass spectrometry-based bottom-up proteomics strategy, the protein abundance of 30 samples was analyzed: five sequential serum samples from six high-risk women; three who developed a breast malignancy (cases) and three who did not (controls). Serum samples were chromatographically fractionated and an in-depth serum proteome was acquired. Cluster analyses were applied to indicate differences between and within protein levels in serum samples of individuals. Statistical analyses were performed using ANOVA to select proteins with a high level of clustering. Cluster analyses on 30 serum samples revealed unique patterns of protein clustering for each patient, indicating a greater interpatient than intrapatient variability in protein levels of the longitudinally acquired samples. Moreover, the most distinctive proteins in the cluster analysis were identified. Strong clustering patterns within longitudinal intrapatient samples have demonstrated the importance of identifying small changes in protein levels for individuals over time. This underlines the significance of longitudinal serum measurements, that patients can serve as their own controls, and the relevance of the current study set-up for early detection. The TESTBREAST study will continue its pursuit toward establishing a protein panel for early breast cancer detection. 相似文献
In the framework of the EC programme for sequencing yeast chromosome XV, we have determined the nucleotide sequence of a 26 kb region. Subsequent analysis revealed 13 non-overlapping open reading frames, three of which correspond to known yeast genes. A pair of tRNA genes associated with remnant Ty elements were localized in this region. From structural parameters and/or similarity searches with entries in the current data libraries, a preliminary functional assessment of several of the putative novel gene products can be made. The gene density in this region amounts to one gene in 2 kb. Protein coding regions occupy 61% of the total DNA sequence. Within the intergenic regions, potential regulatory elements can be predicted. The data obtained here may serve as a basis for a more detailed biochemical analysis of the novel genes. The complete nucleotide sequence of the 26 kb segment as depicted in Figure 1 has been deposited at the EBI data library under Accession Number X91067. 相似文献
In this article, modeling of junction formation in scaled Si device is shown. An atomistic kinetic Monte Carlo (KMC) diffusion modeling is used for the analysis of dopant diffusion and defects during shallow junction formation processes. Dopant diffusion and defect evolution during sub-millisecond non-melt laser annealing (NLA) are studied in both experiments and an atomistic kMC diffusion modeling. Pre-amorphization implant is often used for ultra shallow junction formation. It is shown that Solid Phase Epitaxial Regrowth (SPER) annealing stage plays an important role for dopant diffusion in junction formation process. As Ge implant energy is increased, damage structure and IV composition of Amorphous Pockets are changed and this affects the dopant diffusion and activation behavior. KMC simulations show that B, As deactivation is induced by the formation of dopant-defect complexes, such as BnIm, AsnVm, AsnIm, Asn, during millisecond annealing time range. Both experiments and KMC show that defect evolution during millisecond annealing time range. Fluorine, Carbon co-implant effects are also modeled using KMC. 相似文献
8‐Benzyl‐substituted tetrahydropyrazino[2,1‐f]purinediones were designed as tricyclic xanthine derivatives containing a basic nitrogen atom in the tetrahydropyrazine ring to improve water solubility. A library of 69 derivatives was prepared and evaluated in radioligand binding studies at adenosine receptor (AR) subtypes and for their ability to inhibit monoamine oxidases (MAO). Potent dual‐target‐directed A1/A2A adenosine receptor antagonists were identified. Several compounds showed triple‐target inhibition; one of the best compounds was 8‐(2,4‐dichloro‐5‐fluorobenzyl)‐1,3‐dimethyl‐6,7,8,9‐tetrahydropyrazino[2,1‐f]purine‐2,4(1H,3H)‐dione ( 72 ) (human AR: Ki A1 217 nM , A2A 233 nM ; IC50 MAO‐B: 508 nM ). Dichlorinated compound 36 [8‐(3,4‐dichlorobenzyl)‐1,3‐dimethyl‐6,7,8,9‐tetrahydropyrazino[2,1‐f]purine‐2,4(1H,3H)‐dione] was found to be the best triple‐target drug in rat (Ki A1 351 nM , A2A 322 nm; IC50 MAO‐B: 260 nM ), and may serve as a useful tool for preclinical proof‐of‐principle studies. Compounds that act at multiple targets relevant for symptomatic as well as disease‐modifying treatment of neurodegenerative diseases are expected to show advantages over single‐target therapeutics. 相似文献
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