Evolutionary transitions from outcrossing to selfing in flowering plants have convergent morphological and genomic signatures and can involve parallel evolution within related lineages. Adaptive ...evolution of morphological traits is often assumed to evolve faster than nonadaptive features of the genomic selfing syndrome. We investigated phenotypic and genomic changes associated with transitions from distyly to homostyly in the Primula oreodoxa complex. We determined whether the transition to selfing occurred more than once and investigated stages in the evolution of morphological and genomic selfing syndromes using 22 floral traits and both nuclear and plastid genomic data from 25 populations. Two independent transitions were detected representing an earlier and a more recently derived selfing lineage. The older lineage exhibited classic features of the morphological and genomic selfing syndrome. Although features of both selfing syndromes were less developed in the younger selfing lineage, they exhibited parallel development with the older selfing lineage. This finding contrasts with the prediction that some genomic changes should lag behind adaptive changes to morphological traits. Our findings highlight the value of comparative studies on the timing and extent of transitions from outcrossing to selfing between related lineages for investigating the tempo of morphological and molecular evolution.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Although ammonia borane (NH3BH3, AB) has been identified as an excellent hydrogen‐storage medium, the development of a highly active catalyst that can function under mild conditions for controllable ...hydrogen release is still a great challenge. The synergistic effect induced by interactions between metal nanoparticles and a support has been widely applied in thermocatalytic conversion processes. In this work, Pd nanoparticles (NPs) highly dispersed on hollow NiCo layered double hydroxide (LDH) were designed for efficient hydrogen generation from AB at room temperature. During the hydrolytic dehydrogenation of AB, Pd/α‐LDH and Pd/β‐LDH exhibited catalytic activities with total turnover frequency (TOF) values of 49.5 and 28.1 min−1 with activation energy (Ea) values of 20.56 and 37.56 kJ mol−1, respectively, at 298 K; thus, these catalysts outperform most Pd‐based catalysts. The improved catalytic effect was attributed to the controllable size and fine distribution of the Pd NPs and the collaborative effect provided by the hydroxide of α‐LDH and the intercalated anions (HO−). This catalysts design principle can be easily transferred to other catalyst research fields for energy‐conversion and ‐storage purposes.
Layer of darkness: Pd nanoparticles (NPs) are highly dispersed onto the hollow NiCo layered double hydroxide (LDH) derived from ZIF‐67 through an in situ reduction method. The nanocomposite exhibits superior catalytic performance for hydrogen generation from ammonia borane in aqueous solution at room temperature.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Studies examining the association between alcohol intake and the risk of pancreatic cancer have given inconsistent results. The purpose of this study was to summarize and examine the evidence ...regarding the association between alcohol intake and pancreatic cancer risk based on results from prospective cohort studies.
We searched electronic databases consisting of PubMed, Ovid, Embase, and the Cochrane Library identifying studies published up to Aug 2015. Only prospective studies that reported effect estimates with 95% confidence intervals (CIs) for the risk of pancreatic cancer, examining different alcohol intake categories compared with a low alcohol intake category were included. Results of individual studies were pooled using a random-effects model.
We included 19 prospective studies (21 cohorts) reporting data from 4,211,129 individuals. Low-to-moderate alcohol intake had little or no effect on the risk of pancreatic cancer. High alcohol intake was associated with an increased risk of pancreatic cancer (risk ratio RR, 1.15; 95% CI: 1.06-1.25). Pooled analysis also showed that high liquor intake was associated with an increased risk of pancreatic cancer (RR, 1.43; 95% CI: 1.17-1.74). Subgroup analyses suggested that high alcohol intake was associated with an increased risk of pancreatic cancer in North America, when the duration of follow-up was greater than 10 years, in studies scored as high quality, and in studies with adjustments for smoking status, body mass index, diabetes mellitus, and energy intake..
Low-to-moderate alcohol intake was not significantly associated with the risk of pancreatic cancer, whereas high alcohol intake was associated with an increased risk of pancreatic cancer. Furthermore, liquor intake in particular was associated with an increased risk of pancreatic cancer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The spike glycoprotein （S） of recently identified Middle East respiratory syndrome coronavirus （MERS-CoV） tar- gets the cellular receptor, dipeptidyl peptidase 4 （DPP4）. Sequence comparison and ...modeling analysis have revealed a putative receptor-binding domain （RBD） on the viral spike, which mediates this interaction. We report the 3.0 X- resolution crystal structure of MERS-CoV RBD bound to the extracellular domain of human DPP4. Our results show that MERS-CoV RBD consists of a core and a receptor-binding subdomain. The receptor-binding subdomain interacts with DPP4 IS-propeller but not its intrinsic hydrolase domain. MERS-CoV RBD and related SARS-CoV RBD share a high degree of structural similarity in their core subdomains, but are notably divergent in the receptor- binding subdomain. Mutagenesis studies have identified several key residues in the receptor-binding subdomain that are critical for viral binding to DPP4 and entry into the target cell. The atomic details at the interface between MERS-CoV RBD and DPP4 provide structural understanding of the virus and receptor interaction, which can guide development of therapeutics and vaccines against MERS-CoV infection.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The sluggish four‐electron oxygen evolving reaction is one of the key limitations of photoelectrochemical water decomposition. Optimizing the binding of active sites to oxygen in water and promoting ...the conversion of *O to *OOH are the key to enhancing oxygen evolution reaction. In this work, W‐doped Cu2V2O7 (CVO) constructs corner‐sharing tetrahedrally coordinated W‐V dual active sites to induce the generation of electron deficiency active centers, promote the adsorption of ─OH, and accelerate the transformation of *O to *OOH for water splitting. The photocurrent obtained by the W‐modified CVO photoanode is 0.97 mA cm−2 at 1.23 V versus RHE, which is much superior to that of the reported CVO. Experimental and theoretical results show that the excellent catalytic performance may be attributed to the formation of synergistic dual active sites between W and V atoms, and the introduction of W ions reduces the charge migration distance and prolongs the lifetime of photogenerated carriers. Meanwhile, the electronic structure in the center of the d‐band is modulated, which leads to the redistribution of the electron density in CVO and lowers the energy barrier for the conversion of the rate‐limiting step *O to *OOH.
The constructed corner‐sharing tetrahedrally coordinated W‐V dual active sites in W‐doped Cu2V2O7 produce electron deficiency active centers, which promote the adsorption of –OH and accelerate the transformation of *O to *OOH for water splitting.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
During cancer therapy, phagocytic clearance of dead cells plays a vital role in immune homeostasis. The nonapoptotic form of cell death, ferroptosis, exhibits extraordinary potential in tumor ...treatment. However, the phagocytosis mechanism that regulates the engulfment of ferroptotic cells remains unclear. Here, we establish a novel pathway for phagocytic clearance of ferroptotic cells that is different from canonical mechanisms by using diverse ferroptosis models evoked by GPX4 dysfunction/deficiency. We identified the oxidized phospholipid, 1-steaoryl-2-15-HpETE-sn-glycero-3-phosphatidylethanolamine (SAPE-OOH), as a key eat-me signal on the ferroptotic cell surface. Enriching the plasma membrane with SAPE-OOH increased the efficiency of phagocytosis of ferroptotic cells by macrophage, a process that was suppressed by lipoprotein-associated phospholipase A
. Ligand fishing, lipid blotting, and cellular thermal shift assay screened and identified TLR2 as a membrane receptor that directly recognized SAPE-OOH, which was further confirmed by TLR2 inhibitors and gene silencing studies. A mouse mammary tumor model of ferroptosis verified SAPE-OOH and TLR2 as critical players in the clearance of ferroptotic cells in vivo. Taken together, this work demonstrates that SAPE-OOH on ferroptotic cell surface acts as an eat-me signal and navigates phagocytosis by targeting TLR2 on macrophages.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Bimetallic CuNi nanoparticles (NPs) with low cost were rationally confined inside MIL-101 to give CuNi@MIL-101, which exhibits high efficiency and excellent recyclability toward the hydrogenation of ...nitroarenes under mild conditions on coupling with ammonia borane dehydrogenation. This is the first report on MOF-stabilized base metal NPs for cascade reactions.
Elimination of malignant cells is an unmet challenge for most human cancer types even with therapies targeting specific driver mutations. Therefore, a multi‐pronged strategy to alter cancer cell ...biology on multiple levels is increasingly recognized as essential for cancer cure. One such aspect of cancer cell biology is the relative apoptosis resistance of tumor‐initiating cells. Here, we provide an overview of the mechanisms affecting the apoptotic process in tumor cells emphasizing the differences in the tumor‐initiating or stem‐like cells of cancer. Further, we summarize efforts to exploit these differences to design therapies targeting that important cancer cell population.
Cancer stem‐like cells are less sensitive to apoptotic signals and more resistant to therapy. This review discusses the regulation of apoptosis in CSCs, focusing on the therapeutical modulation of pro‐ and anti‐apoptotic pathways to induce CSC death.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Hydrogen storage in chemicals is regarded as one of the sustainable techniques for tackling the energy-related challenges. However, hydrogen production from ammonia borane (NH3BH3, AB) is restricted ...by the inherent activity of metallic catalysts, which may be boosted by light irradiation. Herein, Pd-doped Co nanoparticles (NPs) were incorporated into a Zr-MOF composite composed of MXene-derived Ti3C2 nanosheets and UiO-66-NH2 (denoted as TUNS) by a double-solvent approach, obtaining a CoPd@TUNS composite. The optimized Co30Pd@TUNS composite exhibited outstanding catalytic activity for the complete dehydrogenation of AB within 0.6 min under 300 W Xe lamp light, with a high turnover frequency of 130.37 molH2 (molmetal)−1 min−1 at 298 K. The activity of Co30Pd@TUNS increased 10-fold under light irradiation as compared to that in the dark. For photocatalytic dehydrogenation, Co30Pd@TUNS was more active than Co30Pd@UiO-66-NH2 and Co30Pd/Ti3C2. Its excellent performance might be attributed to multiple factors including the photo-harvesting MOF generating electron–hole pairs, Ti3C2 nanosheets promoting the charge separation, and the Schottky effect facilitating electron migration to metal NPs for activating the substrate via an electron-deficient BH3 moiety, along with the attack of photogenerated hydroxyl radicals and water molecules. Moreover, the kinetic study manifested that AB dehydrogenation is a zero-order reaction with regard to the substrate. The great stability and recyclability of Co30Pd@TUNS was also confirmed after 5 runs. This study would widen a pathway for the design of an efficient MOF-based catalyst for hydrogen generation in the energy-related field.
To exploit the low-cost and efficient catalyst for the hydrolytic dehydrogenation of ammonia borane, trace amount of palladium-doped transition metal (Cu, Ni, Co, Fe and Zn) nanoparticles have been ...incorporated into the interior of metal-organic frameworks named ZIF-8, ZIF-67, ZIF-67/ZIF-8 and core-shell ZIF-67@ZIF-8 by a double-solvent approach. The optimized catalyst of CuPd0.01@ZIF-67@ZIF-8 composite exhibited an excellent activity with a turnover frequency (TOF) value of 30.15 mol H2 (molmetal)−1 min−1 at 298 K and a relatively low activation energy of 38.78 kJ mol−1. It might attributed to both ultrafine size of metal nanoparticles (~3 nm) induced by the confinement of core-shell ZIF-67@ZIF-8 and the synergistic effect between Pd and Cu. Moreover, the detailed kinetic study has manifested that this catalytic reaction is first-order in regards to the catalyst amount while zero-order as for the concentration of ammonia borane. In addition, the durability and recyclability of CuPd0.01@ZIF-67@ZIF-8 have been demonstrated to be great.
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•Pd-doped Cu nanoparticles were confined by zeolitic imidazolate frameworks (ZIFs).•CuPd0.01@ZIF-67@ZIF-8 remarkably catalyzed the hydrolysis of ammonia borane.•The catalyst had the great durability and recyclability.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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