Marangoni‐effect‐driven actuators (MDAs) have the advantages of direct light‐to‐work conversion and convenient operation, which makes it widely researched in the cutting‐edge fields including robots, ...micromachines, and intelligent systems. However, the MDA relies on the surface tension difference and it only works on the 2D liquid–air interface. Besides, the MDAs are normally pure black due to the light‐absorption material limitation. Herein, a transparent light‐driven 3D movable actuator (LTMA) and a 3D manipulation strategy are proposed. The LTMA is composed of photothermal nanoparticles‐doped temperature‐responsive hydrogel, whose surface energy changes as the nanoparticles absorb light energy. The 3D manipulation strategy combines Marangoni effect with photothermal buoyancy flow for realizing complex self‐propellant and floating/sinking motions. The LTMA can perform more advanced tasks such as 3D obstacle avoidance and 3D sampling. Benefiting from the porous structure of hydrogel, LTMA can naturally absorb the chemical molecules for remote sampling and automated drug delivery. The light‐driven, transparent, three‐dimensionally movable, and programmable actuator has promising prospects in the field of micromachines and intelligent systems.
A transparent light‐driven 3D actuator (LTMA) is prepared using hydrogel and photothermal nanoparticles. The LTMA can not only realize the propulsion movements on the liquid‐air interface based on Marangoni effect but also can realize the floating/sinking motions based on the photo‐thermal buoyancy flow. The LTMA with programmable controllability has promising prospects in the field of micromachines and intelligent systems.
Cross-species transmission of viruses from wildlife animal reservoirs poses a marked threat to human and animal health
. Bats have been recognized as one of the most important reservoirs for emerging ...viruses and the transmission of a coronavirus that originated in bats to humans via intermediate hosts was responsible for the high-impact emerging zoonosis, severe acute respiratory syndrome (SARS)
. Here we provide virological, epidemiological, evolutionary and experimental evidence that a novel HKU2-related bat coronavirus, swine acute diarrhoea syndrome coronavirus (SADS-CoV), is the aetiological agent that was responsible for a large-scale outbreak of fatal disease in pigs in China that has caused the death of 24,693 piglets across four farms. Notably, the outbreak began in Guangdong province in the vicinity of the origin of the SARS pandemic. Furthermore, we identified SADS-related CoVs with 96-98% sequence identity in 9.8% (58 out of 591) of anal swabs collected from bats in Guangdong province during 2013-2016, predominantly in horseshoe bats (Rhinolophus spp.) that are known reservoirs of SARS-related CoVs. We found that there were striking similarities between the SADS and SARS outbreaks in geographical, temporal, ecological and aetiological settings. This study highlights the importance of identifying coronavirus diversity and distribution in bats to mitigate future outbreaks that could threaten livestock, public health and economic growth.
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Protein Phosphatase Mg2+/Mn2+‐Dependent 1K (PPM1K),also named as PP2Cm or branched‐chain α‐ketoacid dehydrogenase complex phosphatase, is a member of the metal‐dependent phosphatase family and an ...important metabolic regulator. Single nucleotide polymorphisms (SNPs) in PPM1K contributing to protein functional defects have been found to be associated with numerous human diseases, such as cardiovascular disease, maple syrup urine disease, type 2 diabetes, and neurological disease. PPM1K N94K is an identified missense mutant produced by one of the SNPs in the human PPM1K coding sequence. However, the effects of the N94K mutant on its activity and structural property have not been defined. Here, we performed a detailed enzymological study using steady‐state kinetics in the presence of pNPP or phospho‐peptide substrates and crystallographic analyses of the wild‐type and N94K PPM1K. The PPM1K‐N94K significantly impaired its Mg2+‐dependent catalytic activity and structural analysis demonstrated that the N94K mutation induced a conformational change in the key residue in coordinating the Mg2+ in the active site. Specifically, three Mg2+ were located in the active site of the PPM1K N94K instead of two Mg2+ in the PPM1K wild type. Therefore, our results provide a structure basis for the metal ion‐dependent PPM1K‐N94K phosphatase activity.
The crystallographic study disclosed that the N94K mutation caused the conformational change in the key residue in coordinating the Mg2+ in the active site. Specifically, three Mg2+ were located in the active site instead of the two Mg2+ in the wild type. Our results provide a structure basis for the metal ion‐dependent PPM1K‐N94K phosphatase activity.
The molecular diversity of aggregation‐induced emission remains a challenge due to the limitation of conventional synthesis methods. Here, a series of novel neutral and cationic conjugated polymers ...composed of various ratios of tetraarylethylene (TAE) containing a bridged oxygen (O) and fluorene (F) units is designed and synthesized via the geminal cross‐coupling (GCC) of 1,1‐dibromoolefins. The incorporation of TAE segments into the conjugated backbone of polyfluorene produces pronounced aggregation‐induced ratiometric fluorescence, i.e., aggregation‐induced emission (AIE) at 520–600 nm and grows synergistically with aggregations‐caused quenching (ACQ) at 400–450 nm. The content of fluorene unit in the polymer backbones determines the intensity of the initial fluorescence in the blue light region. The huge distinction (about 150 nm) in dual emission wavelengths caused by the environment change makes these conjugated polyelectrolytes particularly suitable for ratiometric fluorescence sensing. Based on electrostatic interaction mechanism, the gradual addition of heparin into the cationic conjugated polymers aqueous solutions can induce dual‐color fluorescence changes with a detection limit of 9 × 10−9 m. This work exhibits the great facility of using GCC reaction to synthesis the conjugated TAE polymers with superior AIE properties and special functions.
A series of novel cationic conjugated polyelectrolytes POaF1+b+ containing tetraarylethylene and fluorene are constructed by geminal cross‐coupling reaction. They show high‐contrast dual‐color ratiometric fluorescence response to physical environment change and have been used as fluorescence sensors for heparin detection with a high detection limit of 9 × 10−9 m and a high selectivity.
Long noncoding RNAs (lncRNAs) have been reported to exert important roles in tumors, including clear cell renal cell carcinoma (ccRCC). PVT1 is an important oncogenic lncRNA which has critical ...effects on onset and development of various cancers, however, the underlying mechanism of PVT1 functioning in ccRCC remains largely unknown. VHL deficiency-induced HIF2α accumulation is one of the major factors for ccRCC. Here, we identified the potential molecular mechanism of PVT1 in promoting ccRCC development by stabilizing HIF2α. PVT1 was significantly upregulated in ccRCC tissues and high PVT1 expression was associated with poor prognosis of ccRCC patients. Both gain-of-function and loss-of function experiments revealed that PVT1 enhanced ccRCC cells proliferation, migration, and invasion and induced tumor angiogenesis in vitro and in vivo. Mechanistically, PVT1 interacted with HIF2α protein and enhanced its stability by protecting it from ubiquitination-dependent degradation, thereby exerting its biological significance. Meanwhile, HIF2α bound to the enhancer of PVT1 to transactivate its expression. Furthermore, HIF2α specific inhibitor could repress PVT1 expression and its oncogenic functions. Therefore, our study demonstrates that the PVT1/ HIF2α positive feedback loop involves in tumorigenesis and progression of ccRCC, which may be exploited for anticancer therapy.
GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, ...which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14-GPR101-Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.
Continuous use of synthetic insecticides increases environmental contamination and resistance in many species. Botanical insecticides, such as essential oil, were considered to be suitable ...alternatives due to multiple modes of action and low mammalian toxicity. Haplophyllum dauricum is a overlooked plant for the control of stored-product insects. Five essential oils (EOs) from Haplophyllum dauricum collected in October and November, rich in pinene, were extracted and evaluated on anti-insect activity against two stored-product insects, Tribolium castaneum (Coleoptera: Tenebrionidae) and Lasioderma serricorne (Coleoptera: Anobiidae). The lethal doses (LD50 and LD90), lethal concentrations (LC50 and LC90) and percentage repellency (PR) were evaluated. The GC-MS analysis showed that pinene (α-pinene and β-pinene) were major constituent of the EOs (54.61% and 57.33% in fruits, 46.80% in stems + leaves, and 30.57% in leaves), followed by β-phellandrene (14.49% and 21.34% in fruits and leaves), 3-carene (26.84% in leaves) and limonene (15.77%, 11.09%, 12.40%, 7.59%, and 6.24% in five EOs, respectively). Five EOs and selected major compounds provided promising fumigant, contact and repellent activity against T. castaneum and L. serricorne. The EO of stems + leaves collected in October showed the strongest contact toxicity on T. castaneum (LD50 = 20.21μg/adult), as well as fumigant and contact toxicity on L. serricorne (LC50 = 17.17 mg/L air, LD50 = 25.46 μg/adult). All the five EOs exhibited effective repellent activity (PR>80%) against T. castaneum. The results highlight that the EOs from H. dauricum have a promising potential as eco-friendly botanical insecticides.
•The compositions of five essential oils from different parts of Haplophyllum dauricum (L.) G. Don collected in different time were analyzed.•Insecticidal and repellent activities of the five EOs and selected major compounds were evaluated to be effective on the control of Tribolium castaneum and Lasioderma serricorne.•Essential oils from different parts of Haplophyllum dauricum and its major compounds have potential for development of natural insecticides and repellents on pest control.
Thirteen previously undescribed iridoids (1–13), together with five known iridoids (14–18) were isolated from the roots and rhizomes of Valeriana jatamansi Jones. Their structures with absolute ...configurations were elucidated by analysis of MS, NMR, optical rotation and their experimental and calculated electronic circular dichroism spectra. All of the isolated compounds were tested for their protective effects against α-hemolysin-induced cell death in A549 cells. Compounds 14, 16 and 17 showed moderate protective effects, and compounds 15 and 18 showed weak protective effects.
Eighteen iridoids including thirteen previously undescribed ones were isolated from Valeriana jatamansi Jones and some of them exhibited protective effects against α-hemolysin-induced cell death in A549 cells. Display omitted
•Thirteen previously undescribed iridoids were isolated from Valeriana jatamansi.•Compounds 1 and 2 were unique iridoids with isovaleroxy at C-1 and C-3.•Compounds 14, 16 and 17 showed moderate protective effects against α-hemolysin.
Covalent organic frameworks (COFs), a class of porous crystalline organic polymers, have emerged as promising materials for photocatalysis. Structural functionalization of COFs is an effective ...strategy to improve their photocatalytic performance. However, this approach is mainly limited within interior parts of COFs. Herein we report exterior functionalization of a one-dimensional (1D) COF by introducing terpyridine units on its edges to anchor Pt(
ii
) cations. The as-obtained 1D COF (Pt-Tpy-COF) exhibits high photocatalytic activity for hydrogen evolution from water, with a hydrogen evolution rate up to 7.8 mmol g
−1
h
−1
. Experimental studies and theoretical calculations reveal that the high performance of Pt-Tpy-COF benefits from its distinct 1D framework with readily accessible active sites. This study not only demonstrates the potential of 1D COFs as photocatalysts, but also provides valuable insights for the design and development of highly efficient catalysts for various catalytic applications based on the structural features of this new type of nanoporous crystalline framework materials.
Exterior functionalization of a one-dimensional (1D) covalent organic framework (COF) was achieved by introducing terpyridine units on its edges to anchor Pt(
ii
) cations. It exhibits high photocatalytic activity for hydrogen evolution from water.
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease with no currently approved treatment. The natural compound silybin (SLN) has versatile hepatoprotective efficacy ...with negligible adverse effects; however, poor absorption limits its clinical applications. Gut microbiota has been proposed to play a crucial role in the pathophysiology of NAFLD and targeted for disease control. Cyclodextrins, the cyclic oligosaccharides, were documented to have various health benefits with potential prebiotic properties. This study aimed to develop a silybin-2-hydroxypropyl-β-cyclodextrin inclusion (SHβCD) to improve the therapeutic efficacy of SLN and elucidate the mechanisms of improvement. The results showed that SLN formed a 1:1 stoichiometric inclusion complex with HP-β-CD. The solubility of SLN was increased by generating SHβCD, resulting in improved drug permeability and bioavailability. In high-fat diet (HFD)-fed hamsters, SHβCD modulated gut health by restoring the gut microbiota and intestinal integrity. SHβCD showed superior anti-lipid accumulation, antioxidant, and anti-inflammatory effects compared with SLN alone. Transcriptome analysis in the liver tissue implied that the improved inflammation and/or energy homeostasis was the potential mechanism. Therefore, SHβCD may be a promising alternative for the treatment of NAFLD, attributing to the dual functions of HβCD on drug absorption and gut microbial homeostasis.
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