Publications by authors named "Kang Guo"

A copper-catalyzed remote 1,5-trifluoromethyl thio(seleno)cyanation of 5-hexenenitriles with an intramolecular cyano migration has been established, affording a variety of CF/CN-containing thiocyanates and selenocyanates under mild conditions. The reaction features high chemo- and regioselectivities and illustrates potential value in synthetic chemistry.

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A new three-component 1,2-perfluoroalkyl trifluoromethylthiolation of alkenes via dual photoredox/copper catalysis has been established, affording a variety of CF/CFS-containing molecules under mild conditions in a redox-neutral manner. This protocol exhibits excellent functional group tolerance, broad compatibility with various alkenes and perfluoroalkyl iodides, and potential utility in the modification of bioactive molecules.

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Root System Architecture (RSA) is a crucial plant trait that governs a plant's ability to absorb water and nutrients. In this study, we describe a mutant with nutrient-dependent defects in root development, affecting both the primary root and lateral roots (LRs). This mutant, identified through a screen for defects in LR development, has been designated dlr1-1.

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A copper-catalyzed trifunctionalization (trifluoromethylation, heteroarylation, and cyanation) of heteroaryl-substituted 1-hexenes via remote heteroaryl migration is reported. A variety of CF and heteroaryl-containing nitriles were readily constructed under mild conditions. The reaction features high chemo- and regioselectivities and represents a convenient method for the synthesis of multifunctionalized molecules in organic synthesis.

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Total synthesis of simonsol C has been achieved, focusing on the postdearomatization transformations. Our methodology integrates an efficient combination of dearomatization and Zn/AcOH reduction to introduce an allyl group, followed by oxo-Michael addition, to construct the 6/5/6 benzofuran skeleton. It offers a novel method for synthesizing allyl-containing quaternary carbon atoms in a straightforward manner.

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Unsaturated lipids constitute a significant portion of the lipidome, serving as players of multifaceted functions involving cellular signaling, membrane structure, and bioenergetics. While derivatization-assisted liquid chromatography tandem mass spectrometry (LC-MS/MS) remains the gold standard technique in lipidome, it mainly faces challenges in efficiently labeling the carbon-carbon double bond (C═C) and differentiating isomeric lipids in full dimension. This presents a need for new orthogonal methodologies.

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A silver-catalyzed decarboxylative remote fluorination via a zwitterion-promoted 1,4-heteroaryl migration has been developed. A variety of heteroaryl-tethered benzyl fluorides have been readily synthesized with good regioselectivity under mild conditions. The zwitterion of the substrate is suggested to accelerate the 1,4-heteroaryl migration, which determines the regioselectivity of this transformation.

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A photoinduced copper-catalyzed enantioconvergent remote alkynylation of -hydroxyphthalimide esters with terminal alkynes via 1,4-heteroaryl migration has been developed. A broad scope of heteroaryl-tethered chiral alkynes has been synthesized with good regio- and enantioselectivities. The chiral-ligand-coordinated copper species plays a dual role as both the photoredox and cross-coupling catalyst.

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Multi-degree of freedom piezoelectric actuators are strongly needed for industrial applications, especially when manipulating a large and heavy mirror or lens in an optical system. A novel three-degree-of-freedom piezoelectric actuator, which is driven by two pairs of piezo-stack actuator with spatial compliant mechanisms designed to guide the motion and preload the piezo-stack actuators, is herein proposed. The structure and working principle of the proposed actuator are illustrated and its kinematic characteristic is analyzed.

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With the synchronous development of highway construction and the urban economy, automobiles have entered thousands of households as essential means of transportation. This paper reviews the latest research progress in using phytoremediation technology to remediate the environmental pollution caused by automobile exhaust in recent years, including the prospects for stereoscopic forestry. Currently, most automobiles on the global market are internal combustion vehicles using fossil energy sources as the primary fuel, such as gasoline, diesel, and liquid or compressed natural gas.

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We have developed a photoredox/Cu dual catalyzed enantioselective remote cyanation 1,4-heteroaryl migration. Experimental and computational studies have been carried out to reveal the reaction mechanism and explain the origins of the regio- and enantioselectivities of the remote cyanation process. This methodology exhibits mild conditions, a broad substrate scope and good regio- and enantioselectivities, which provides a unique approach for catalyst-controlled asymmetric backbone recombination of molecules functional group migration.

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Glioma is one of the most common primary brain tumors. Gambogic acid (GA) is widely used in tumor chemotherapy. However, GA has poor water solubility, low bioavailability, and difficult permeability across the blood-brain barrier (BBB), leading to poor efficacy against brain tumors.

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The nucleus accumbens (NAc) is the key area of the reward circuit, but its heterogeneity has been poorly studied. Using single-cell RNA sequencing, we revealed a subcluster of GABAergic neurons characterized by cell division cycle 20 (Cdc20) mRNA expression in the NAc of adult rats. We studied the coexpression of Cdc20 and Gad1 mRNA in the NAc neurons of adult rats and assessed Cdc20 protein expression in the NAc during rat development.

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Background: The blood-brain barrier (BBB) inhibits the delivery of macromolecular chemotherapeutic drugs to brain tumors, leading to low utilization rates and toxic side effects to surrounding tissues and organs. Ultrasonic targeted microbubble destruction (UTMD) technology can open the BBB, leading to a new type of drug delivery system with particular utility in glioma.

Purpose: We have developed a new type of drug-loaded microbubble complex based on poly(lactic-co-glycolic acid) (PLGA) that targets gambogic acid (GA) to the area of brain tumors through UTMD.

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A novel and efficient Brønsted acid-promoted hydroamination of hydrazone-tethered olefins has been developed. A variety of pyrazolines have been easily obtained in good to excellent yields with high chemo- and regioselectivity under simple and mild conditions. This method represents a straightforward, facile, and practical approach toward biologically important 5-arylpyrazolines, which are difficult to access by previously reported radical hydroamination of β,γ-unsaturated hydrazones.

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The performance of lithium batteries is largely dependent on the ionic conductivity within robust solid electrolytes. Poly(ethylene oxide) (PEO)-based electrolytes, however, have a low lithium ionic conductivity, which limits the hop of Li. Herein, a novel PEO-based composite electrolyte is prepared that contains nonstoichiometric transition molybdenum trioxide (MoO) nanosheets as fillers to improve the ionic conductivity.

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In this paper, we have adopted a simple and etching-free method to prepare mesoporous carbon spheres in one step. Selenium can be deposited in the internal cavity, which can avoid pulverization due to the combined effect of volume expansion and a solid-electrolyte interphase (SEI) film while charging and discharging. Therefore, the as-prepared selenium and nitrogen codoped mesoporous carbon nanosphere (Se@NMCS) composites can deliver an outstanding sodium-storage performance of 336.

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Stroke has been the leading cause of adult morbidity and mortality over the past several years. After an ischemic stroke attack, many dormant or reversibly injured brain cells exist in the penumbra area. However, the pathological processes and unique cell information in the penumbra area of an acute ischemic stroke remain elusive.

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Traumatic brain injury (TBI) triggers the activation of the endogenous coagulation mechanism, and a large amount of thrombin is released to curb uncontrollable bleeding through thrombin receptors, also known as protease-activated receptors (PARs). However, thrombin is one of the most critical factors in secondary brain injury. Thus, the PARs may be effective targets against hemorrhagic brain injury.

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When using foil queue microelectrodes (FQ-microelectrodes) for micro electrical discharge machining (micro-EDM), the processed results of each foil microelectrode (F-microelectrode) can be stacked to construct three-dimensional (3D) microstructures. However, the surface of the 3D microstructure obtained from this process will have a step effect, which has an adverse effect on the surface quality and shape accuracy of the 3D microstructures. To focus on this problem, this paper proposes to use FQ-microelectrodes with tapered structures for micro-EDM, thereby eliminating the step effect on the 3D microstructure's surface.

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There is growing evidence shown that microRNAs (miRNAs) are associated with cancer and can play a role in human cancers as oncogenes or tumor suppressor genes. miRNA-574-5p is a candidate oncogene in various types of cancer, but little is known about biological functions of miR-574-5p in esophageal squamous cell carcinoma (ESCC). In this study, we observe that the expression of miR-574-5p is not only increased in human ESCC tissues but also remarkably increased in cell lines correlates with ZNF70.

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Objective: Low levels of adiponectin (APN), a biomarker of diabetes mellitus, have been implicated in the poor outcome of intracerebral haemorrhage (ICH). Herein, we aimed to demonstrate the neuroprotective effects of a blood-brain barrier-permeable APN peptide (APNp) on ICH injury in diabetic mice and explore the underlying mechanisms.

Materials And Methods: Recombinant APNp was administrated intraperitoneally to mice with collagenase-induced ICH.

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Intracerebral hemorrhage (ICH) is a life-threatening subtype of cerebral stroke with high morbidity and mortality; however, effective treatment for ICH is still lacking. Adiponectin (APN) is a a kind of fat-derived plasma protein with beneficial effects in cerebrovascular disorders. In this study, we aimed to investigate the protective effects of recombinant APN peptide (APNp) on brain injury after ICH in adult male C57BL/6J mice and further explored the underlying molecular mechanisms of these effects.

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N-myc downstream-regulated gene 2 (NDRG2), a newly identified astrocytic stress response gene, is involved in the regulation of astrocytic morphology and function, and has been indicated to be a potential therapeutic target for some central nervous system (CNS) diseases. However, the role of NDRG2 in intracerebral hemorrhage (ICH) remains unknown. Here, we reported that NDRG2 suppression exerted neuroprotection effect against hemorrhagic brain injury in ICH mice and in oxyhemoglobin (OxyHb)-treated cells.

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