It is a huge challenge to have a controllable interfacial polymerization in the fabrication process of nanofiltration (NF) membranes. In this work, a polyphenol interlayer consisting of ...polyethyleneimine (PEI)/tannic acid (TA) was simply assembled on the polysulfone (PSf) substrate to fine-tune the interfacial polymerization process, without additional changes to the typical NF membrane fabrication procedures. In addition, three decisive factors in the interfacial polymerization process were examined, including the diffusion kinetics of fluorescence-labeled piperazine (FITC-PIP), the spreading behavior of the hexane solution containing acyl chloride, and the polyamide layer formation on the porous substrate by in situ Fourier transform infrared (FT-IR) spectroscopy. The experimental results demonstrate that the diffusion kinetics of FITC-PIP is greatly reduced, and the spreading behavior of the hexane solution is also impeded to some extent. Furthermore, in situ FT-IR spectroscopy demonstrates that by the mitigation of this PEI/TA interlayer, the interfacial polymerization process is greatly controlled. Moreover, the as-prepared NF membrane exhibits an increased water permeation flux of 65 L m–2 h–1 (at the operation pressure of 0.6 MPa), high Na2SO4 rejection of >99%, and excellent long-term structural stability.
Biochar was modified as a high efficient and selective absorbent for copper ions (Cu(II)) by nitration and reduction. Results of X-ray photoelectron spectroscopy (XPS) and attenuated total ...reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) analyses indicated that the amino groups were chemically bound to the functional groups on the biochar surface. Kinetics, thermal dynamics, and adsorption and desorption of Cu(II) in fixed-bed were investigated. The results demonstrated that the amino-modified biochar exhibited excellent adsorption performance for Cu(II). The adsorption capacity and bed volume of the modified biochar are five- and eight- folds of the pristine biochar, respectively. The Cu(II) combined with the amino groups through strong complexation based on the comparison of XPS and ATR-FTIR analyses before and after adsorption, which endows it with the high pH stability and ion selectivity.
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•We proposed an innovative method to modify the biochar with amino groups.•The amino groups were anchored onto the biochar surface by chemical bonding.•Electrophilic aromatic substitution and nitro reduction reactions are involved.•The high adsorption capacity for Cu2+ is ascribed to the complexation.
Background
Early diagnosis of liver metastasis is of great importance for enhancing the survival of colorectal adenocarcinoma (CAD) patients, and the combined use of a single biomarker in a classier ...model has shown great improvement in predicting the metastasis of several types of cancers. However, it is little reported for CAD. This study therefore aimed to screen an optimal classier model of CAD with liver metastasis and explore the metastatic mechanisms of genes when applying this classier model.
Methods
The differentially expressed genes between primary CAD samples and CAD with metastasis samples were screened from the Moffitt Cancer Center (MCC) dataset GSE131418. The classification performances of six selected algorithms, namely, LR, RF, SVM, GBDT, NN, and CatBoost, for classification of CAD with liver metastasis samples were compared using the MCC dataset GSE131418 by detecting their classification test accuracy. In addition, the consortium datasets of GSE131418 and GSE81558 were used as internal and external validation sets to screen the optimal method. Subsequently, functional analyses and a drug‐targeted network construction of the feature genes when applying the optimal method were conducted.
Results
The optimal CatBoost model with the highest accuracy of 99%, and an area under the curve of 1, was screened, which consisted of 33 feature genes. A functional analysis showed that the feature genes were closely associated with a “steroid metabolic process” and “lipoprotein particle receptor binding” (eg APOB and APOC3). In addition, the feature genes were significantly enriched in the “complement and coagulation cascade” pathways (eg FGA, F2, and F9). In a drug‐target interaction network, F2 and F9 were predicted as targets of menadione.
Conclusion
The CatBoost model constructed using 33 feature genes showed the optimal classification performance for identifying CAD with liver metastasis.
APOB, APOC3, FGA, F2, F9, and NKX2‐3 were potential biomarkers for classification of CAD with liver metastasis. Menadione might be a promising anti‐metastatic drug of CAD cells through functioning its role at sites of F2 and F9. CatBoost model constructed by 33 feature genes showed the optimal classification performance for identifying CAD liver metastasis.
Patients with acute myocardial infarction receive a P2Y
12
receptor antagonist prior to reperfusion, a treatment that has reduced, but not eliminated, mortality, or heart failure. We tested whether ...the caspase-1 inhibitor VX-765 given at reperfusion (a requirement for clinical use) can provide sustained reduction of infarction and long-term preservation of ventricular function in a pre-clinical model of ischemia/reperfusion that had been treated with a P2Y
12
receptor antagonist. To address, the hypothesis open-chest rats were subjected to 60-min left coronary artery branch occlusion/120-min reperfusion. Vehicle or inhibitors were administered intravenously immediately before reperfusion. With vehicle only, 60.3 ± 3.8% of the risk zone suffered infarction. Ticagrelor, a P2Y
12
antagonist, and VX-765 decreased infarct size to 42.8 ± 3.3 and 29.2 ± 4.9%, respectively. Combining ticagrelor with VX-765 further decreased infarction to 17.5 ± 2.3%. Similar to recent clinical trials, combining ticagrelor and ischemic postconditioning did not result in additional cardioprotection. VX-765 plus another P2Y
12
antagonist, cangrelor, also decreased infarction and preserved ventricular function when reperfusion was increased to 3 days. In addition, VX-765 reduced infarction in blood-free, isolated rat hearts indicating at least a portion of injurious caspase-1 activation originates in cardiac tissue. While the pro-drug VX-765 only protected isolated hearts when started prior to ischemia, its active derivative VRT-043198 provided the same amount of protection when started at reperfusion, indicating that even in blood-free hearts, caspase-1 appears to exert its injury only at reperfusion. Moreover, VX-765 decreased circulating IL-1β, prevented loss of cardiac glycolytic enzymes, preserved mitochondrial complex I activity, and decreased release of lactate dehydrogenase, a marker of pyroptosis. Our results are the first demonstration of a clinical-grade drug given at reperfusion providing additional, sustained infarct size reduction when added to a P2Y
12
receptor antagonist.
The functions of Sertoli cells in spermatogenesis have attracted much more attention recently. Normal spermatogenesis depends on Sertoli cells, mainly due to their influence on nutrient supply, ...maintenance of cell junctions, and support for germ cells' mitosis and meiosis. Accumulating evidence in the past decade has highlighted the dominant functions of the MAPK, AMPK, and TGF-β/Smad signaling pathways during spermatogenesis. Among these pathways, the MAPK signaling pathway regulates dynamics of tight junctions and adherens junctions, proliferation and meiosis of germ cells, proliferation and lactate production of Sertoli cells; the AMPK and the TGF-β/Smad signaling pathways both affect dynamics of tight junctions and adherens junctions, as well as the proliferation of Sertoli cells. The AMPK signaling pathway also regulates lactate supply. These signaling pathways combine to form a complex regulatory network for spermatogenesis. In testicular tumors or infertile patients, the activities of these signaling pathways in Sertoli cells are abnormal. Clarifying the mechanisms of signaling pathways in Sertoli cells on spermatogenesis provides new insights into the physiological functions of Sertoli cells in male reproduction, and also serves as a pre-requisite to identify potential therapeutic targets in abnormal spermatogenesis including testicular tumor and male infertility.
Recent advances in remote sensing of solar‐induced chlorophyll fluorescence (SIF) have garnered wide interest from the biogeoscience and Earth system science communities, due to the observed ...linearity between SIF and gross primary productivity (GPP) at increasing spatiotemporal scales. Three recent studies, Maguire et al., (2020, https://doi.org/10.1029/2020GL087858), He et al. (2020, https://doi.org/10.1029/2020GL087474), and Marrs et al. (2020, https://doi.org/10.1029/2020GL087956) highlight a nonlinear relationship between fluorescence and photochemical yields and show empirical evidence for the decoupling of SIF, stomata, and the carbon reactions of photosynthesis. Such mechanistic studies help advance our understanding of what SIF is and what it is not. We argue that these findings are not necessarily contradictory to the linear SIF‐GPP relationship observed at the satellite scale and provide context for where, when, and why fluorescence and photosynthesis diverge at smaller spatiotemporal scales. Understanding scale dependencies of remote sensing data is crucial for interpreting SIF as a proxy for GPP.
Plain Language Summary
When exposed to light, plants re‐emit a small amount of light from chlorophyll molecules called fluorescence. Remote sensing instruments are now capable of measuring chlorophyll fluorescence (which is emitted between 650–850 nm) from canopies to the globe (solar‐induced chlorophyll fluorescence; SIF). A growing number of papers have highlighted an empirical linear relationship between SIF and whole‐ecosystem photosynthesis (gross primary productivity; GPP). These advances have excited the broader Earth science research community, but recent studies have pointed out that the linear SIF‐GPP relationship at coarse scales does not hold true at smaller spatiotemporal scales. In this commentary, we synthesize three recent studies that provide insight into the relationship between fluorescence and photosynthesis at leaf and canopy scales, under natural and controlled conditions. At fine spatiotemporal scales, fluorescence can be decoupled with photosynthetic carbon uptake, but we argue that satellite measurements are often too coarse in time and space to observe the SIF‐photosynthesis decoupling and that the integration of canopy processes explains the observed linearity. As such, SIF plays an important role as an estimate of GPP at spatial and temporal scales relevant for monitoring global terrestrial productivity, benchmarking terrestrial biosphere and earth system models, and managing ecosystems.
Key Points
Solar‐induced fluorescence (SIF) is widely used as a remote estimate of ecosystem gross primary productivity (GPP), but why does it work?
Three recent studies point to inherent nonlinearities in the fluorescence‐photosynthesis relationship at fine spatiotemporal scales
We synthesize mechanisms to suggest that these results are not contradictory to the increasingly linear SIF:GPP relationship across scales
In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and ...total phenolic acids varied between 166.20-237.60, 170.10-240.75 and 336.29-453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61-25.59, 14.91-22.38 and 37.91-47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH
free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS
free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH
and ABTS
free radical scavenging capacity in the free phenolic extract, while chlorogenic acid, vanillic acid, ferulic acid and quercetin were the main contributors to the free radical scavenging capacity in the bound phenol extract. The study results show that the blue highland barley grains have rich phenolic compounds and high antioxidant activity, as well as significant varietal differences. The free and bound phenolic extracts in the blue hulless barley grains have an equivalent proportion in the total phenol, and co-exist in two forms. They can be used as a potential valuable source of natural antioxidants, and can aid in enhancing the development and daily consumption of foods relating to blue highland barley.
During eukaryote cell division, molecular motors are crucial regulators of microtubule organization, spindle assembly, chromosome segregation and intracellular transport. The kinesin-14 motors are ...evolutionarily conserved minus-end-directed kinesin motors that occur in diverse organisms from simple yeasts to higher eukaryotes. Members of the kinesin-14 motor family can bind to, crosslink or slide microtubules and, thus, regulate microtubule organization and spindle assembly. In this Commentary, we present the common subthemes that have emerged from studies of the molecular kinetics and mechanics of kinesin-14 motors, particularly with regard to their non-processive movement, their ability to crosslink microtubules and interact with the minus- and plus-ends of microtubules, and with microtubule-organizing center proteins. In particular, counteracting forces between minus-end-directed kinesin-14 and plus-end-directed kinesin-5 motors have recently been implicated in the regulation of microtubule nucleation. We also discuss recent progress in our current understanding of the multiple and fundamental functions that kinesin-14 motors family members have in important aspects of cell division, including the spindle pole, spindle organization and chromosome segregation.
In humans, Interleukin-8 (IL-8 or CXCL8) is a granulocytic chemokine with multiple roles within the tumor microenvironment (TME), such as recruiting immunosuppressive cells to the tumor, increasing ...tumor angiogenesis, and promoting epithelial-to-mesenchymal transition (EMT). All of these effects of CXCL8 on individual cell types can result in cascading alterations to the TME. The changes in the TME components such as the cancer-associated fibroblasts (CAFs), the immune cells, the extracellular matrix, the blood vessels, or the lymphatic vessels further influence tumor progression and therapeutic resistance. Emerging roles of the microbiome in tumorigenesis or tumor progression revealed the intricate interactions between inflammatory response, dysbiosis, metabolites, CXCL8, immune cells, and the TME. Studies have shown that CXCL8 directly contributes to TME remodeling, cancer plasticity, and the development of resistance to both chemotherapy and immunotherapy. Further, clinical data demonstrate that CXCL8 could be an easily measurable prognostic biomarker in patients receiving immune checkpoint inhibitors. The blockade of the CXCL8-CXCR1/2 axis alone or in combination with other immunotherapy will be a promising strategy to improve antitumor efficacy. Herein, we review recent advances focusing on identifying the mechanisms between TME components and the CXCL8-CXCR1/2 axis for novel immunotherapy strategies.
Ferroptosis is a novel form of nonapoptotic regulated cell death (RCD). It features iron-dependent lipid peroxide accumulation accompanied by inadequate redox enzymes, especially glutathione ...peroxidase 4 (GPX4). RAS-selective lethal 3 (RSL3), erastin, and ferroptosis inducing 56 (FIN56) induce ferroptosis via different manners targeting GPX4 function. Acyl-CoA synthetase long-chain family 4 (ACSL4), lysophosphatidylcholine acyltransferase 3 (LPCAT3), and lipoxygenases (LOXs) participate in the production of lipid peroxides. Heat shock protein family B member 1 (HSPB1) and nuclear receptor coactivator 4 (NCOA4) regulate iron homeostasis preventing ferroptosis caused by the high concentration of intracellular iron. Ferroptosis is ubiquitous in our body as it exists in both physiologic and pathogenic processes. It is involved in glucose-stimulated insulin secretion (GSIS) impairment and arsenic-induced pancreatic damage in the pathogenesis of diabetes. Moreover, iron and the iron-sulfur (Fe-S) cluster influence each other, causing mitochondrial iron accumulation, more reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, failure in biosynthesis of insulin, and ferroptosis in β-cells. In addition, ferroptosis also engages in the pathogenesis of diabetic complications such as myocardial ischemia and diabetic cardiomyopathy (DCM). In this review, we summarize the mechanism of ferroptosis and especially its association with type 2 diabetes mellitus (T2DM).
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