Anticancer agents are critical for the cancer treatment, but side effects and the drug resistance associated with the currently used anticancer agents create an urgent need to explore novel drugs ...with low side effects and high efficacy. 1,2,3-Triazole is privileged building block in the discovery of new anticancer agents, and some of its derivatives have already been applied in clinics or under clinical trials for fighting against cancers. Hybrid molecules occupy an important position in cancer control, and hybridization of 1,2,3-triazole framework with other anticancer pharmacophores may provide valuable therapeutic intervention for the treatment of cancer, especially drug-resistant cancer. This review emphasizes the recent advances in 1,2,3-triazole-containing hybrids with anticancer potential, covering articles published between 2015 and 2019, and the structure-activity relationships, together with mechanisms of action are also discussed.
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•1,2,3-Triazole drugs have already been used in clinics for cancer treatment.•1,2,3-Triazole-containing hybrids with potential anticancer activity.•The SAR was enriched.
The coronavirus disease 2019 (COVID-19) emerged in Wuhan, China in the end of 2019, and soon became a serious public health threat globally. Due to the unobservability, the time interval between ...transmission generations (TG), though important for understanding the disease transmission patterns, of COVID-19 cannot be directly summarized from surveillance data. In this study, we develop a likelihood framework to estimate the TG and the pre-symptomatic transmission period from the serial interval observations from the individual transmission events. As the results, we estimate the mean of TG at 4.0 days (95%CI: 3.3-4.6), and the mean of pre-symptomatic transmission period at 2.2 days (95%CI: 1.3-4.7). We approximate the mean latent period of 3.3 days, and 32.2% (95%CI: 10.3-73.7) of the secondary infections may be due to pre-symptomatic transmission. The timely and effectively isolation of symptomatic COVID-19 cases is crucial for mitigating the epidemics.
The objective of this study was to study the structure and physicochemical properties of biochar derived from apple tree branches (ATBs), whose valorization is crucial for the sustainable development ...of the apple industry. ATBs were collected from apple orchards located on the Weibei upland of the Loess Plateau and pyrolyzed at 300, 400, 500 and 600 °C (BC300, BC400, BC500 and BC600), respectively. Different analytical techniques were used for the characterization of the different biochars. In particular, proximate and element analyses were performed. Furthermore, the morphological, and textural properties were investigated using scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, Boehm titration and nitrogen manometry. In addition, the thermal stability of biochars was also studied by thermogravimetric analysis. The results indicated that the increasing temperature increased the content of fixed carbon (C), the C content and inorganic minerals (K, P, Fe, Zn, Ca, Mg), while the yield, the content of volatile matter (VM), O and H, cation exchange capacity, and the ratios of O/C and H/C decreased. Comparison between the different samples show that highest pH and ash content were observed in BC500. The number of acidic functional groups decreased as a function of pyrolysis temperature, especially for the carboxylic functional groups. In contrast, a reverse trend was found for the basic functional groups. At a higher temperature, the brunauer–emmett–teller (BET) surface area and pore volume are higher mostly due to the increase of the micropore surface area and micropore volume. In addition, the thermal stability of biochars also increased with the increasing temperature. Hence, pyrolysis temperature has a strong effect on biochar properties, and therefore biochars can be produced by changing pyrolysis temperature in order to better meet their applications.
Dysregulated extravillous trophoblast invasion and proliferation are known to increase the risk of recurrent spontaneous abortion (RSA); however, the underlying mechanism remains unclear. Herein, in ...our retrospective observational case-control study we show that villous samples from RSA patients, compared to healthy controls, display reduced succinate dehydrogenase complex iron sulfur subunit (SDHB) DNA methylation, elevated SDHB expression, and reduced succinate levels, indicating that low succinate levels correlate with RSA. Moreover, we find high succinate levels in early pregnant women are correlated with successful embryo implantation. SDHB promoter methylation recruited MBD1 and excluded c-Fos, inactivating SDHB expression and causing intracellular succinate accumulation which mimicked hypoxia in extravillous trophoblasts cell lines JEG3 and HTR8 via the PHD2-VHL-HIF-1α pathway; however, low succinate levels reversed this effect and increased the risk of abortion in mouse model. This study reveals that abnormal metabolite levels inhibit extravillous trophoblast function and highlights an approach for RSA intervention.
Abiotic stress severely influences plant growth and development. MYB transcription factors (TFs), which compose one of the largest TF families, play an important role in abiotic stress responses.
We ...identified 139 soybean MYB-related genes; these genes were divided into six groups based on their conserved domain and were distributed among 20 chromosomes (Chrs). Quantitative real-time PCR (qRT-PCR) indicated that GmMYB118 highly responsive to drought, salt and high temperature stress; thus, this gene was selected for further analysis. Subcellular localization revealed that the GmMYB118 protein located in the nucleus. Ectopic expression (EX) of GmMYB118 increased tolerance to drought and salt stress and regulated the expression of several stress-associated genes in transgenic Arabidopsis plants. Similarly, GmMYB118-overexpressing (OE) soybean plants generated via Agrobacterium rhizogenes (A. rhizogenes)-mediated transformation of the hairy roots showed improved drought and salt tolerance. Furthermore, compared with the control (CK) plants, the clustered, regularly interspaced, short palindromic repeat (CRISPR)-transformed plants exhibited reduced drought and salt tolerance. The contents of proline and chlorophyll in the OE plants were significantly greater than those in the CK plants, whose contents were greater than those in the CRISPR plants under drought and salt stress conditions. In contrast, the reactive oxygen species (ROS) and malondialdehyde (MDA) contents were significantly lower in the OE plants than in the CK plants, whose contents were lower than those in the CRISPR plants under stress conditions.
These results indicated that GmMYB118 could improve tolerance to drought and salt stress by promoting expression of stress-associated genes and regulating osmotic and oxidizing substances to maintain cell homeostasis.
Carbon materials are frequently used to improve the cycle and rate performance of VS4 as anode material for lithium ion batteries. However, the interfacial interaction between VS4 and carbon has not ...been elucidated clearly. Various VS4@C composites are prepared and the interface between VS4 and porous carbon is investigated by X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and first‐principles calculations. The interfacial structure between VS4 and carbon and the mechanism of flower‐like VS4 growth on carbon substrate are revealed clearly. The results indicate that C−V bonds and C−O−V bonds are formed when oxygen functional groups are introduced into the porous carbon, and the C−V bonds and C−O−V bonds accelerate the electron transport and enhance structural stability of the VS4@C composite. Deriving from the unique structure and robust interfacial interaction, the electrochemical performances of VS4@C composite are much better than that of pure VS4. Moreover, through the study of lithium storage mechanism of VS4 anode, it is found that there is an irreversible amorphization change of the original VS4 in the first cycle, and that during the following electrochemical process, the main storage behavior of lithium ions derives from the insertion−extraction reactions in the amorphous VS4 with the reaction between V4+ and V3+.
Carbon materials are frequently used to improve the cycle and rate performances of VS4 as anode material for lithium ion batteries. However, the interface between VS4 and carbon is unclear. It is demonstrated that the robust “skeletons” of vanadium−carbon and vanadium−oxygen−carbon between VS4 and carbon material are the origin of this synergistic effect.
WRKYs are important regulators in plant development and stress responses. However, knowledge of this superfamily in soybean is limited. In this study, we characterized the drought- and salt-induced ...gene
based on RNA-Seq and qRT-PCR.
, which is 714 bp in length, encoded 237 amino acids and grouped into WRKY II. The promoter region of
included ABER4, MYB, MYC, GT-1, W-box and DPBF
-elements, which possibly participate in abscisic acid (ABA), drought and salt stress responses.
was minimally expressed in different tissues under normal conditions but highly expressed under drought and salt treatments. As a nucleus protein,
was responsive to drought, salt, ABA and salicylic acid (SA) stresses. Using a transgenic hairy root assay, we further characterized the roles of
in abiotic stress tolerance. Compared with control (Williams 82), overexpression of
enhanced drought and salt tolerance, increased proline (Pro) content and decreased malondialdehyde (MDA) content under drought and salt treatment in transgenic soybean seedlings. These results may provide a basis to understand the functions of
in abiotic stress responses in soybean.
Tin diselenide (SnSe2) nanosheets as novel 2D layered materials have excellent optical properties with many promising application prospects, such as photoelectric detectors, nonlinear optics, ...infrared photoelectric devices, and ultrafast photonics. Among them, ultrafast photonics has attracted much attention due to its enormous advantages; for instance, extremely fast pulse, strong peak power, and narrow bandwidth. In this work, SnSe2 nanosheets are fabricated by using solvothermal treatment, and the characteristics of SnSe2 are systemically investigated. In addition, the solution of SnSe2 nanosheets is successfully prepared as a fiber‐based saturable absorber by utilizing the evanescent field effect, which can bear a high pump power. 31st‐order subpicosecond harmonic mode locking is generated in an Er‐doped fiber laser, corresponding to the maximum repetition rate of 257.3 MHz and pulse duration of 887 fs. The results show that SnSe2 can be used as an excellent nonlinear photonic device in many fields, such as frequency comb, lasers, photodetectors, etc.
Tin diselenide (SnSe2) nanosheets as novel 2D layered materials have excellent optical properties. SnSe2 nanosheets fabricated by using solvothermal treatment are successfully prepared as fiber‐based saturable absorbers by utilizing the evanescent field effect, which can bear a high pump power. 31st‐order subpicosecond harmonic mode‐locking is generated, corresponding to 257.3 MHz repetition rate.
The process for separating and purifying lithium in brines based on electrodialysis with monovalent selective ion exchange membranes was investigated in our previous work. The migration of coexisting ...cations in brines was competitive with lithium ions, especially monovalent cations (Na+ and K+). The aim of this study was to examine the influence of major coexisting cations in brines on lithium recovery in the selective-electrodialysis (S-ED) process. Considering the factors of coexisting cations, such as concentration and type, some migration laws of lithium ion were found as follows: the concentration of coexisting cations had negative effect on the migration of lithium ion; the influence order of coexisting cations on lithium migration was contrary to their hydrated radius sequence: K+>Na+>Ca2+>Mg2+. In order to characterize the migration process of cations through monovalent selective cation exchange membrane in microcosmic theory, a partial dehydration conceptual model based on charge capillary column theory and ionic potential was proposed. And the model was used to characterize the ions migration process. Simultaneously, considering the hydration potential which indicates how strongly an ion would attract water molecules, the influence sequence of coexisting cations was explained legitimately. These observations might provide some theoretical basis and technological support for the relevant research of recovering lithium from brines.
A partial dehydration conceptual model of ion migration in the cation exchange membrane. Display omitted
•Selective-electrodialysis (S-ED) was used to recover lithium from brine.•Effect of coexisting cations concentration on lithium recovery by S-ED was investigated.•The influence sequence of coexisting cations on lithium migration was K+>Na+>Ca2+>Mg2+.•A partial dehydration model was proposed to discuss the separation mechanism of cations in S-ED process.
Tunable halofluoroalkylation and hydrofluoroalkylation of 1,6‐enynes were first reported by switching between copper‐catalysis and photocatalysis, leading to the atom‐economic and highly ...stereoselective protocols toward functionalized 1‐indenones with moderate to good yields. Copper‐catalysis enabled the concomitant incorporation of two important fluoroalkyl and halo functionalities into 1‐indenone skeleton, in which fluoroalkyl bromides were transformed into (E)‐1‐indenones as a major stereoisomer while fluoroalkyl iodides oriented complete Z‐selectivity to access (Z)‐1‐indenones. Specifically, photocatalysis allowed hydrofluoroalkylation of 1,6‐enynes to access fluoroalkylated (Z)‐1‐indenones under mild conditions, in which THF behaved as a hydrogen source. These two approaches feature remarkable compatibility with a wide variety of 1,6‐enynes and fluoroalkyl halides and excellent atomic utilization.
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