Publications by authors named "Dongyang Li"

114 Publications

Development of nanobody-based flow-through dot ELISA and lateral-flow immunoassay for rapid detection of 3-phenoxybenzoic acid.

Anal Methods 2021 04 24;13(14):1757-1765. Epub 2021 Mar 24.

School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.

As a major metabolite of pyrethroid pesticides, 3-phenoxybenzoic acid (3-PBA) can be an indicator of health risk and human exposure assessment. Based on nanobodies (Nbs), we have developed a rapid flow-through dot enzyme linked immunosorbent assay (dot ELISA) and gold nanoparticle (GNP) lateral-flow immunoassay for detecting 3-PBA. The limit of detection (LOD) values for detecting 3-PBA by flow-through dot ELISA and GNP lateral-flow immunoassay were 0.01 ng mL and 0.1 ng mL, respectively. The samples (urine and lake water) with and without 3-PBA were detected by both nanobody-based flow-through dot ELISA and GNP lateral-flow immunoassay, as well as liquid chromatography-mass spectrometry (LC-MS) for validation. There was good consistency between the results of the immunoassays. This demonstrated that the two developed nanobody-based immunoassays are suitable for rapid detection of 3-PBA.
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http://dx.doi.org/10.1039/d1ay00129aDOI Listing
April 2021

Mitochondrial genome of Glover cucumber biotype (Hemiptera: Aphididae).

Mitochondrial DNA B Resour 2021 Mar 16;6(3):922-924. Epub 2021 Mar 16.

Institute of Cotton Research of Chinese Academy of Agricultural Sciences, State Key Laboratory of Cotton Biology, Anyang, Henan, China.

The complete mitochondrial genome of Glover cucumber biotype was sequenced using traditional PCR amplification coupled with Sanger sequencing. The genome is 15,870 bp long, with 83.7% AT content (MW048625). The genome encodes 37 typical mitochondrial genes, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNAs, a repeat region of 784 bp, and a control region of 627 bp. The base composition of the genome is A (45.4%), T (38.3%), C (10.5%), and G (5.8%). An analysis of two biotypes mitogenomes identified 77 single nucleotide polymorphisms and 1 insertion and deletion.
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http://dx.doi.org/10.1080/23802359.2021.1888328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7971299PMC
March 2021

Morita-Baylis-Hillman-Type [3,3]-Rearrangement: Switching from Z- to E-Selective α-Arylation by New Rearrangement Partners.

Angew Chem Int Ed Engl 2021 05 7;60(20):11414-11422. Epub 2021 Apr 7.

Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua, 321004, China.

α-aryl α,β-unsaturated carbonyls represent an important class of derivatizable synthetic intermediates, however, the synthesis of such compounds still remains a challenge. Recently, we showcased a novel Z-selective α-arylation of α,β-unsaturated nitriles with aryl sulfoxides via [3,3]-rearrangement involving an Morita-Baylis-Hillman (MBH) process. Herein, we demonstrate the feasibility of reversing the stereoselectivity of such MBH-type [3,3]-rearrangement by switching to a new pair of rearrangement partners consisting of aryl iodanes and α,β-unsaturated oxazolines. As a result, the two protocols complement each other in approaching E- or Z-α-aryl α,β-unsaturated carbonyl derivatives. Mechanistic studies reveal a possible reaction pathway and provide an explanation for the opposite stereoselectivities.
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http://dx.doi.org/10.1002/anie.202100497DOI Listing
May 2021

Different expressions of clock genes in fatty liver induced by high-sucrose and high-fat diets.

Chronobiol Int 2021 May 22;38(5):762-778. Epub 2021 Feb 22.

Department of Nutritional Science, National Institute of Health and Nutrition, National Institutes of Biomedical Innovation, Health and Nutrition, Tokyo, Japan.

Sucrose consumption can cause obesity and nonalcoholic fatty liver disease (NAFLD). NAFLD is associated with the disruption of circadian rhythms. We compared the alterations in NAFLD circadian rhythms induced by a high-sucrose diet (HSD) with those induced by a high-fat diet (HFD) in mice. After 8 weeks of feeding, the liver triglyceride level was increased by HSD feeding and by HFD feeding. In the liver of HSD-fed mice, the amplitude of and the mesor (time series 24 h mean value based on the distribution of values across the cycle of the circadian rhythm) of and were increased in comparison to those of control-diet fed mice. Compared with the HFD-fed mice, the HSD-fed mice showed increased circadian amplitude of variation in , and and mesors of , and in the liver. appeared to play critical roles in the entrainment of HSD into the liver circadian system, and the increased expressions of s and might disrupt circadian rhythms. Thus, disruption of circadian rhythms by HSD and HFD may accelerate the accumulation of liver lipid through different mechanisms.
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http://dx.doi.org/10.1080/07420528.2021.1889579DOI Listing
May 2021

Involvement of Protein Kinase A in Oxytocin Neuronal Activity in Rat Dams with Pup Deprivation.

Neurochem Res 2021 Apr 21;46(4):980-991. Epub 2021 Feb 21.

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, Harbin, 150081, China.

Oxytocin (OT) neuronal activity is the key factor for breastfeeding and it can be disrupted by mother-baby separation. To explore cellular mechanisms underlying OT neuronal activity, we studied the role of protein kinase A (PKA) in OT neuronal activity in the supraoptic nucleus (SON) using a rodent model of pup deprivation (PD) Intermittent (IPD) or continuous (CPD) PD significantly reduced suckling duration and number of milk ejections in lactating rats, particularly those with CPD. In Western blots of the SON, PD increased expressions of OT receptor (OTR) and its immediate downstream effectors, Gαq and Gβ subunits, particularly IPD, but reduced the expression of catalytic subunit of PKA (cPKA). In brain slices, inhibition of PKA blocked prostaglandin E-evoked increase in firing activity including burst firing in OT neurons. In IPD dams, filamentous actin formed ring-like structures in the cytoplasmic region of OT neurons, which was reduced in CPD. Moreover, molecular association between actin and cPKA also reduced in PD dams. Incubation of brain slices with OT reduced the expression of cPKA, which was blocked by pretreatment with atosiban, an antagonist of OTR. These results indicate that PD disrupts OT neuronal activity through dissociating the Gq proteins and PKA in OTR-associated signaling cascade, which couples with reduced interactions between filamentous actin and PKA in OT neurons in the SON. This study highlights that PKA can be a novel target treating abnormal OT neuronal activity and its associated diseases.
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http://dx.doi.org/10.1007/s11064-020-03218-5DOI Listing
April 2021

Preservation of epoxyeicosatrienoic acid bioavailability prevents renal allograft dysfunction and cardiovascular alterations in kidney transplant recipients.

Sci Rep 2021 Feb 12;11(1):3739. Epub 2021 Feb 12.

Department of Pharmacology, Rouen University Hospital, 76000, Rouen, France.

This study addressed the hypothesis that epoxyeicosatrienoic acids (EETs) synthesized by CYP450 and catabolized by soluble epoxide hydrolase (sEH) are involved in the maintenance of renal allograft function, either directly or through modulation of cardiovascular function. The impact of single nucleotide polymorphisms (SNPs) in the sEH gene EPHX2 and CYP450 on renal and vascular function, plasma levels of EETs and peripheral blood monuclear cell sEH activity was assessed in 79 kidney transplant recipients explored at least one year after transplantation. Additional experiments in a mouse model mimicking the ischemia-reperfusion (I/R) injury suffered by the transplanted kidney evaluated the cardiovascular and renal effects of the sEH inhibitor t-AUCB administered in drinking water (10 mg/l) during 28 days after surgery. There was a long-term protective effect of the sEH SNP rs6558004, which increased EET plasma levels, on renal allograft function and a deleterious effect of K55R, which increased sEH activity. Surprisingly, the loss-of-function CYP2C9*3 was associated with a better renal function without affecting EET levels. R287Q SNP, which decreased sEH activity, was protective against vascular dysfunction while CYP2C8*3 and 2C9*2 loss-of-function SNP, altered endothelial function by reducing flow-induced EET release. In I/R mice, sEH inhibition reduced kidney lesions, prevented cardiac fibrosis and dysfunction as well as preserved endothelial function. The preservation of EET bioavailability may prevent allograft dysfunction and improve cardiovascular disease in kidney transplant recipients. Inhibition of sEH appears thus as a novel therapeutic option but its impact on other epoxyfatty acids should be carefully evaluated.
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http://dx.doi.org/10.1038/s41598-021-83274-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7881112PMC
February 2021

Study protocol for a single-centre non-inferior randomised controlled trial on a novel three-dimensional matrix positioning-based cognitive fusion-targeted biopsy and software-based fusion-targeted biopsy for the detection rate of clinically significant prostate cancer in men without a prior biopsy.

BMJ Open 2021 02 5;11(2):e041427. Epub 2021 Feb 5.

Department of Urology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China

Introduction: The classical pathway for diagnosing prostate cancer is systematic 12-core biopsy under the guidance of transrectal ultrasound, which tends to underdiagnose the clinically significant tumour and overdiagnose the insignificant disease. Another pathway named targeted biopsy is using multiparametric MRI to localise the tumour precisely and then obtain the samples from the suspicious lesions. Targeted biopsy, which is mainly divided into cognitive fusion method and software-based fusion method, is getting prevalent for its good performance in detecting significant cancer. However, the preferred targeted biopsy technique in detecting clinically significant prostate cancer between cognitive fusion and software-based fusion is still beyond consensus.

Methods And Analysis: This trial is a prospective, single-centre, randomised controlled and non-inferiority study in which all men suspicious to have clinically significant prostate cancer are included. This study aims to determine whether a novel three-dimensional matrix positioning cognitive fusion-targeted biopsy is non-inferior to software-based fusion-targeted biopsy in the detection rate of clinically significant cancer in men without a prior biopsy. The main inclusion criteria are men with elevated serum prostate-specific antigen above 4-20 ng/mL or with an abnormal digital rectal examination and have never had a biopsy before. A sample size of 602 participants allowing for a 10% loss will be recruited. All patients will undergo a multiparametric MRI examination, and those who fail to be found with a suspicious lesion, with the anticipation of half of the total number, will be dropped. The remaining participants will be randomly allocated to cognitive fusion-targeted biopsy (n=137) and software-based fusion-targeted biopsy (n=137). The primary outcome is the detection rate of clinically significant prostate cancer for cognitive fusion-targeted biopsy and software-based fusion-targeted biopsy in men without a prior biopsy. The clinically significant prostate cancer will be defined as the International Society of Urological Pathology grade group 2 or higher.

Ethics And Dissemination: Ethical approval was obtained from the ethics committee of Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China. The results of the study will be disseminated and published in international peer-reviewed journals.

Trial Registration Number: ClinicalTrials.gov Registry (NCT04271527).
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http://dx.doi.org/10.1136/bmjopen-2020-041427DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7925935PMC
February 2021

Involvement of Supraoptic Astrocytes in Basilar Artery Occlusion-Evoked Differential Activation of Vasopressin Neurons and Vasopressin Secretion in Rats.

Neurochem Res 2021 Feb 2. Epub 2021 Feb 2.

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, 157 Baojian Road, Nangang, Harbin, 150081, China.

Vasopressin (VP) is a key factor in the development of brain injury in ischemic stroke. However, the regulation of VP secretion in basilar artery occlusion (BAO) remains unclear. To clarify the regulation of VP secretion in BAO and the underlying mechanisms, we performed this study in a rat model of BAO with (BC) or without common carotid artery occlusion (CCAO). The results showed that BAO and BC time-dependently increased neurological scores and that BC also increased water contents in the medulla at 2 h and in the pontine at 8 h. Moreover, plasma VP level increased significantly at BAO-8 h, CCAO and BC-2 h but not at BC-8 h; however, VP expressions increased in the supraoptic nucleus (SON) at BC-8 h. The neurological scores were highly correlated with pontine water contents and plasma VP levels. The number of phosphorylated extracellular signal-regulated protein kinase1/2-positive VP neurons increased significantly in the SON at BC-8 h. Similarly, the number of c-Fos-positive VP neurons increased significantly in the SON at BAO-8 h and BC-8 h. In addition, the length of glial fibrillary acidic protein (GFAP) filaments increased significantly in BC compared to BAO only. Aquaporin 4 (AQP4) puncta around VP neurons increased significantly at BC-8 h relative to BC-2 h, which had negative correlation with plasma VP levels. These findings indicate that BAO facilitates VP secretion and increases VP neuronal activity in the SON. The peripheral VP release is possibly under a negative feedback regulation of central VP neuronal activity through increasing GFAP and AQP4 expression in astrocytic processes.
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http://dx.doi.org/10.1007/s11064-021-03246-9DOI Listing
February 2021

Key Roles of Cyclooxygenase 2-Protein Kinase A-Hyperpolarization-activated Cyclic Nucleotide-gated Channel 3 Pathway in the Regulation of Oxytocin Neuronal Activity in Lactating Rats with Intermittent Pup-Deprivation.

Neuroscience 2021 01 31;452:13-25. Epub 2020 Oct 31.

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, Harbin, China. Electronic address:

Suckling-evoked pulsatile release of oxytocin (OT) from the posterior pituitary plays a key role in breastfeeding, which relies on burst-like discharges of OT neurons. To explore cellular mechanisms regulating OT neuronal activity, using lactating rats with pup-deprivation (PD) during postpartum day 1-5, we observed the involvement of prostaglandin, cyclic AMP/protein kinase A (PKA) and hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3) signaling pathway in OT neuronal activity. PD gradually reduced lactation efficiency. Intermittent PD (IPD) was largely reversed by intranasally-applied OT (IAO) but not by hypodermically-applied OT. IPD caused involution-like histological changes in the mammary glands, increased hypothalamic OT release but did not influence plasma OT concentrations. In the supraoptic nucleus, IPD increased OT receptor (OTR) expressions in OT neurons as well as Gαq subunit, Gβ subunit and cyclooxygenase 2 (Cox-2). These effects except that on Gβ subunit were reversed by IAO. Notably, IPD increased the expression of catalytic subunit of PKA in the SON, specifically in vasopressin neurons but not in OT neurons. In addition, IPD increased the expression of HCN3. IAO partially reversed these changes in the SON. Lastly, blocking HCN3 blocked excitation and burst firing in OT neurons-evoked by prostaglandin E, a key mediator of OT-evoked burst firing; blocking Cox-2 or PKA reduced the molecular association between OTR and HCN3. Thus, there is a prostaglandin-cAMP/PKA-HCN3 pathway in the regulation of OT neuronal activity. PD disrupts lactation performance through uncoupling OTR and PKA-HCN3 signaling. The reversal effect of IAO highlights its therapeutic potential in PD-evoked hypogalactia.
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http://dx.doi.org/10.1016/j.neuroscience.2020.10.016DOI Listing
January 2021

Alleviation of brain injury by applying TGN-020 in the supraoptic nucleus via inhibiting vasopressin neurons in rats of focal ischemic stroke.

Life Sci 2021 Jan 28;264:118683. Epub 2020 Oct 28.

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, Harbin, China. Electronic address:

Aims: To understand mechanisms underlying vasopressin hypersecretion in stroke and its association with brain injury, we investigated effects of blocking aquaporin 4 (AQP4) in the supraoptic nucleus (SON) on vasopressin neuronal activity and cerebral injuries in male rats of unilateral middle cerebral artery occlusion (MCAO).

Main Methods: Establishing MCAO model without or with microinjection of TGN-020 into the SON, performing Western blots and immunohistochemistry and analyzing the expression levels and spatial distribution of functional proteins in the SON and/or the cerebral cortex.

Key Findings: MCAO increased plasma vasopressin levels, caused neurological damage and increased glycogen synthase kinase 3β (GSK-3β) in the SON and the cortex of MCAO side. In the SON, MCAO significantly increased c-Fos in vasopressin neurons and astrocytic somata in the ventral glial lamina. MCAO significantly reduced glial fibrillary acidic protein (GFAP) and AQP4 around vasopressin neurons, which accompanied separation of GFAP from AQP4. By contrast, blocking AQP4 by microinjection of TGN-020 into the SON blocked MCAO-evoked GSK-3β increase as well as the reduction of AQP4 relative to GFAP around vasopressin neurons in the SON. In the cortex, TGN-020 in the SON also blocked MCAO-evoked increase in GSK-3β while reduced neurological damages.

Significance: These findings indicate that MCAO disrupts interactions of GFAP with AQP4 in astrocytic processes in the SON, which increases vasopressin neuronal activity. Blocking AQP4 in the SON can block abnormal activation of vasopressin neurons and alleviate ischemic brain injury, which provides novel targets for alleviating ischemic brain injury.
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http://dx.doi.org/10.1016/j.lfs.2020.118683DOI Listing
January 2021

Versatile Optofluidic Solid-Core/Liquid-Cladding Waveguide Based on Evanescent Wave Excitation.

Anal Chem 2020 Nov 27;92(22):14983-14989. Epub 2020 Oct 27.

Department of Electrical Engineering, The University of Texas at Arlington, Arlington, Texas 76019, United States.

In this paper, we present the design and operation of a solid-core/liquid-cladding (SL) waveguide excited by an evanescent wave. To do this, an optical fiber is integrated into a microfluidic channel and pumped along the fiber axis, ensuring the cladding solution is excited by the evanescent field of the guided mode at the core/cladding interface. The pump beam is guided by the total internal reflection in the fiber, providing a uniform excitation along the microfluidic channel. The evanescent wave provides precise excitation to the dye molecules in close proximity to the core/cladding interface, which significantly reduces the background fluorescence and increases the signal-to-noise ratio. Fluorescence intensity measurements of different dye concentrations and refractive indices of the cladding solution are conducted to evaluate their influences on the propagation loss, which shows that the peak intensity propagation loss can be as low as about 0.1 dB/cm. We further exemplify that the intensity of the fluorescence emission and the dye concentration show good linearity when the dye is in the low concentration region (<250 μM). A broad-band and simultaneous light source with a single pump light is also demonstrated by employing cascade SL waveguide segments through fluorescence resonance energy transfer. The proposed SL waveguide demonstrates excellent robustness and is easy to fabricate and use, providing a versatile platform for a variety of applications, such as high-sensitivity detection of low-concentration samples, multiband on-chip light sources, and simultaneous measurement of multiplexed parameters.
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http://dx.doi.org/10.1021/acs.analchem.0c02848DOI Listing
November 2020

Emerging role of ONECUT2 in tumors.

Oncol Lett 2020 Dec 6;20(6):328. Epub 2020 Oct 6.

Department of Geriatrics, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, P.R. China.

One cut domain family member 2 (ONECUT2), also termed OC-2, is a newly discovered member of the ONECUT transcription factor family. As a transcription factor, ONECUT2 can widely regulate protein expression associated with cell proliferation, migration, adhesion, differentiation and cell material metabolism. Recent studies have revealed that ONECUT2 is associated with tumor cell proliferation, angiogenesis and metastasis; it is also associated with epithelial-mesenchymal transition in cancer cells. The present review examines the distribution and expression of ONECUT2 in a variety of tumors, its oncogenic role in tumor progression and the possible mechanisms of regulation. Given the emerging role of ONECUT2 in the development and progression of tumors, ONECUT2 might be a promising target for tumor therapy.
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http://dx.doi.org/10.3892/ol.2020.12192DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7577075PMC
December 2020

Spatial Association of Urbanization in the Yangtze River Delta, China.

Int J Environ Res Public Health 2020 10 5;17(19). Epub 2020 Oct 5.

Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions, Henan University, Ministry of Education, Kaifeng 475004, Henan, China.

China is urbanizing rapidly, but current research into the spatiotemporal characteristics of urbanization often ignores the spatial and evolutionary associations of cities. Using the theory of spatial polarization and diffusion, together with a systematic analysis method, this study examined the spatial development process of urbanization in the Yangtze River Delta (YRD) region of China during 1995-2015. Results showed clear patterns in the scale and hierarchy of regional urbanization. Shanghai ranked first as the regional growth pole, while Nanjing, Hangzhou, and Suzhou ranked second. The spatial linkage index of urbanization showed that 10 cities (including Shanghai, Suzhou, and Hangzhou) constituted the densest spatial linkage network. The diffused area often became spatially polarized before the polarization then weakened as a new diffusion stage developed. The study also revealed that the spatial correlation urbanization differences in the YRD generally decreased. The polarization index revealed increasing spatial integration and correlation of urbanization in the YRD. This study proved that each city had a different spatial role in relation to other cities during different stages of development. Investigation of the driving mechanism of regional urbanization indicated that industrial modernization and relocation within the region provided the main endogenous driving force for the formation of spatial polarization or diffusion. Our research provides important scientific support for regional development planning. Furthermore, our analysis of the impact of spatial correlation within cities or a region could provide an important reference in relation to the regional environment and public health.
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http://dx.doi.org/10.3390/ijerph17197276DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7578991PMC
October 2020

Electrowetting lens with large aperture and focal length tunability.

Sci Rep 2020 10 1;10(1):16318. Epub 2020 Oct 1.

College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin, 300072, China.

The electrowetting lenses has attracted researchers in many fields, such as biology, beam shaping, and drug delivery. Previous research on electrowetting lens has focused on neither expanding the dynamic focal length range nor reducing the wavefront aberration. However, the properties with large numerical aperture and low aberration are also essential properties of lenses, and can promote their application. Therefore, we calculated the meniscus of the lens with different optical apertures, and subsequently, analyzed the relations among the focal length, wavefront aberration, and optical aperture. To expand the focal length range, we designed an electrowetting-based triple-liquid lens with a root-mean-square wavefront aberration error of less than 1/4 waves.
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http://dx.doi.org/10.1038/s41598-020-73260-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7530674PMC
October 2020

Alleviation of Cerebral Infarction of Rats With Middle Cerebral Artery Occlusion by Inhibition of Aquaporin 4 in the Supraoptic Nucleus.

ASN Neuro 2020 Jan-Dec;12:1759091420960550

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, Harbin, China.

In ischemic stroke, vasopressin hypersecretion is a critical factor of cerebral swelling and brain injury. To clarify neural mechanisms underlying ischemic stroke-evoked vasopressin hypersecretion, we observed the effect of unilateral permanent middle cerebral artery occlusion (MCAO) in rats on astrocytic plasticity and vasopressin neuronal activity in the supraoptic nucleus (SON) as well as their associated cerebral injuries. MCAO for 8 hr caused cerebral infarction in the MCAO side where water contents also increased. Immunohistochemical examination revealed that the percentage of phosphorylated extracellular signal-regulated protein kinase 1/2 (pERK1/2)-positive vasopressin neurons in the SON of MCAO side was significantly higher than that in non-MCAO side and in sham group. In the cortex, pERK1/2 and aquaporin 4 expressions increased significantly in the infarction area, while glial fibrillary acidic protein (GFAP) reduced significantly compared with the noninfarction side in brain cortex. Microinjection of N-(1,3,4-Thiadiazolyl)nicotinamide-020 [TGN-020, a specific blocker of aquaporin 4] into the SON blocked MCAO-evoked increases in pERK1/2 in the SON as well as the reduction of GFAP and the increase in pERK1/2 and aquaporin 4 in the infarction area of the cortex. Finally, oxygen and glucose deprivation reduced GFAP expression and the colocalization and molecular association of GFAP with aquaporin 4 in the SON in brain slices. These effects were blocked by TGN-020 and/or phloretin, a blocker of astrocytic volume-regulated anion channels. These findings indicate that blocking aquaporin 4 in the SON may reduce the activation of vasopressin neurons and brain injuries elicited by vasopressin during ischemic stroke.
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http://dx.doi.org/10.1177/1759091420960550DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7545515PMC
September 2020

Involvement of Hyperpolarization-Activated Cyclic Nucleotide-Gated Channel 3 in Oxytocin Neuronal Activity in Lactating Rats With Pup Deprivation.

ASN Neuro 2020 Jan-Dec;12:1759091420944658

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University.

Oxytocin, a hypothalamic neuropeptide essential for breastfeeding, is mainly produced in oxytocin neurons in the supraoptic nucleus (SON) and paraventricular nucleus. However, mechanisms underlying oxytocin secretion, specifically the involvement of hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3) in oxytocin neuronal activity, remain unclear. Using a rat model of intermittent and continuous pup deprivation (PD) at the middle stage of lactation, we analyzed the contribution of HCN3 in oxytocin receptor (OTR)-associated signaling cascade to oxytocin neuronal activity in the SON. PD caused maternal depression, anxiety, milk shortage, involution of the mammary glands, and delays in uterine recovery, particularly in continuous PD. PD increased hypothalamic but not plasma oxytocin levels in enzyme-linked immunosorbent assay. In the SON, PD increased c-Fos expression but reduced expressions of cyclooxygenase-2 and HCN3 in Western blots and/or immunohistochemistry. Moreover, PD significantly increased the molecular association of OTR with HCN3 in coimmunoprecipitation. In brain slices, inhibition of HCN3 activity with DK-AH269 blocked prostaglandin E-evoked increase in the firing activity and burst discharge in oxytocin neurons in patch-clamp recordings. In addition, oxytocin-evoked increase in the molecular association between OTR and HCN3 in brain slices of the SON was blocked by pretreatment with indomethacin, an inhibitor of cyclooxygenase-2. These results indicate that normal activity of oxytocin neurons is under the regulation of an oxytocin receptor-cyclooxygenase-2-HCN3 pathway and that PD disrupts maternal behavior through increasing intranuclear oxytocin secretion in the SON but likely reducing bolus oxytocin release into the blood through inhibition of HCN3 activity.
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http://dx.doi.org/10.1177/1759091420944658DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7517985PMC
September 2020

Astrocytic Modulation of Supraoptic Oxytocin Neuronal Activity in Rat Dams with Pup-Deprivation at Different Stages of Lactation.

Neurochem Res 2020 Sep 15. Epub 2020 Sep 15.

Department of Physiology, School of Basic Medical Sciences, Harbin Medical University, 157 Baojian Road, Nangang, Harbin, 150081, China.

Appropriate interactions between astrocytes and oxytocin neurons in the hypothalamo- neurohypophysial system are essential for normal lactation. To further explore the mechanisms underlying astrocytic modulation of oxytocin neuronal activity, we observed astrocytic plasticity in the supraoptic nucleus of lactating rats with intermittent pup-deprivation (PD, 20 h/day) at early (day 1-5) and middle (day 8-12) stages of lactation. PD at both stages decreased suckling duration and litter's body weight gain. They also significantly increased the expression of glial fibrillary acidic protein (GFAP) in Western blots while increased GFAP filaments and the colocalization of GFAP filaments with aquaporin 4 (AQP4) puncta in astrocyte processes surrounding oxytocin neuronal somata in immunohistochemistry in the supraoptic nucleus. Suckling between adjacent milk ejections but not shortly after them decreased molecular association between GFAP and AQP4. In hypothalamic slices from male rats, oxytocin treatment (0.1 nmol/L, 10 min) significantly reduced the length of GFAP filaments and AQP4 puncta in the processes but increased GFAP staining in the somata. These oxytocin effects were blocked by pretreatment of the slices with N-(1,3,4-Thiadiazolyl) nicotinamide (TGN-020, inhibitor of AQP4, 10 µmol/L, 5 min before oxytocin). In addition, inhibition of AQP4 with TGN-020 blocked excitation in oxytocin neurons evoked by prostaglandin E, a downstream signal of oxytocin receptor and mediator of oxytocin-evoked burst firing, in whole-cell patch-clamp recordings. These results indicate that AQP4-associated astrocytic plasticity is essential for normal oxytocin neuronal activity during lactation and that PD-evoked hypogalactia is associated with astrocytic process expansion following increased GFAP and AQP4 expressions.
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http://dx.doi.org/10.1007/s11064-020-03129-5DOI Listing
September 2020

Long and Ultrastable All-Inorganic Single-Crystal CsPbBrMicrowires: One-Step Solution In-Plane Self-Assembly at Low Temperature and Application for High-Performance Photodetectors.

J Phys Chem Lett 2020 Sep 19;11(17):7224-7231. Epub 2020 Aug 19.

Guangdong Engineering Research Center of Optoelectronic Functional Materials and Devices, Institute of Semiconductors, South China Normal University, Guangzhou 510631, People's Republic of China.

As ideal building blocks for optoelectronic devices, one-dimensional (1D) single-crystal perovskite microwires (MWs) have received widespread attention due to their unique physical and chemical properties. Herein, a one-step solution in-plane self-assembly method is proposed to directly grow millimeter-long CsPbBr MWs with superior crystal quality at atmospheric environment. This method effectively avoids the use of toxic antisolvents. Furthermore, a MW-based photodetector is successfully fabricated, showing high photoresponsivity (20 A/W) and fast response (less than 0.3 ms). The stability of the photodetector is also confirmed by aging MW in air for 60 days, which shows a negligible change of photocurrent from 1.29 to 1.25 nA (-3 V) under the same experimental conditions. This work provides a low-cost and fast synthesis method for the preparation of single-crystal perovskite MWs and demonstrates their potential application for high-performance and stable photoelectronic device.
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http://dx.doi.org/10.1021/acs.jpclett.0c01920DOI Listing
September 2020

Development of a Highly Sensitive Enzyme-Linked Immunosorbent Assay for Mouse Soluble Epoxide Hydrolase Detection by Combining a Polyclonal Capture Antibody with a Nanobody Tracer.

Anal Chem 2020 09 17;92(17):11654-11663. Epub 2020 Aug 17.

Department of Entomology and Nematology, University of California, Davis, Comprehensive Cancer Center, University of California, Davis, Davis, California 95616, United States.

Enzyme-linked immunosorbent assays (ELISA) for the detection of soluble epoxide hydrolase (sEH), a key enzyme in the metabolism of fatty acids and a biomarker, may increasingly represent an important diagnostic tool. However, there is a lack of ELISAs for mouse sEH quantification, thus resulting in a bottleneck in understanding the pathogenesis of many diseases related to sEH based on mouse models. In this work, nanobodies recognizing mouse sEH were obtained through rebiopanning against mouse sEH in the previous phage display library of human sEH. Later, we developed four ELISAs involving a combination of anti-mouse sEH polyclonal antibodies (pAbs) and nanobodies. It was found that the double antibodies worked as dual filters and had a huge impact on both the sensitivity and selectivity of sandwich immunoassays. The switch from anti-human sEH pAbs to anti-mouse sEH pAbs led to over a 100-fold increase in the sensitivity and a dramatic decrease of the limit of detection to a picogram per milliliter range in format B (pAb/biotin-VHH/streptavidin-poly-horseradish peroxidase). Moreover, we found that the four sandwich ELISAs might demonstrate excellent selectivities to mouse sEH, despite the antibodies alone showing significant cross-reactivity to the matrix, indicating the enhanced selectivity of double antibodies as dual filters. Eventually, for the first time, the ELISA (format B) was successfully used to measure the mouse sEH level in cancer cells with ultralow abundances. The ELISAs proposed here represent a sensitive tool for tracking sEH in various biological processes and also provide deep insights into developing sandwich immunoassays against various targets in terms of both the sensitivity and selectivity.
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http://dx.doi.org/10.1021/acs.analchem.0c01511DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7745732PMC
September 2020

On-spot quantitative analysis of dicamba in field waters using a lateral flow immunochromatographic strip with smartphone imaging.

Anal Bioanal Chem 2020 Oct 31;412(25):6995-7006. Epub 2020 Jul 31.

Department of Entomology and Nematology and UCD Comprehensive Cancer Center, University of California, Davis, CA, 95616, USA.

Dicamba herbicide is increasingly used in the world, in particular' with the widespread cultivation of genetically modified dicamba-resistant crops. However, the drift problem in the field has caused phytotoxicity against naive, sensitive crops, raising legal concerns. Thus, it is particularly timely to develop a method that can be used for on-the-spot rapid detection of dicamba in the field. In this paper, a lateral flow immunochromatographic strip (LFIC) was developed. The quantitative detection can be conducted by an app on a smartphone, named "Color Snap." The tool reported here provides results in 10 min and can detect dicamba in water with a LOD (detection limit) value of 0.1 mg/L. The developed LFIC shows excellent stability and sensitivity appropriate for field analysis. Our sensor is portable and excellent tool for on-site detection with smartphone imaging for better accuracy and precision of the results. Graphical abstract.
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http://dx.doi.org/10.1007/s00216-020-02833-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7771584PMC
October 2020

Enhanced Oral Delivery of Curcumin via Vitamin E TPGS Modified Nanodiamonds: a Comparative Study on the Efficacy of Non-covalent and Covalent Conjugated Strategies.

AAPS PharmSciTech 2020 Jul 8;21(5):187. Epub 2020 Jul 8.

School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 110016, People's Republic of China.

Despite that either non-covalent or covalent attachment of hydrophilic polymers or surfactants onto nanodiamonds (NDs) could overcome the shortcomings of being a drug delivery system, it is hard to draw a definite conclusion which strategy is more effective. Hence, with the purpose of comparing the influence of different coating approach of NDs on the oral delivery efficiency of water-insoluble model drug curcumin (CUR), NDs were firstly modified with D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) via non-covalent or covalent conjugation method, and then loaded with CUR (CUR@NDs-COOH/TPGS or CUR@NDs-TPGS). In comparison with the core-shell-structured CUR@NDs-COOH/TPGS, CUR@NDs-TPGS were irregular in shape with dense TPGS film, and exhibited smaller size, more negatively potential, and higher drug loading efficiency. The covalent connection group also showed higher anti-cancer activity, cellular uptake, and permeability through the Caco-2 cell monolayers, as well as favorable distribution, penetration, and retention in rat intestines. The oral bioavailability study in rats demonstrated that CUR@NDs-TPGS showed significantly greater C and AUC in contrast with CUR suspension and the TPGS-coated ones, respectively. The findings illustrated that covalent grafting TPGS onto the surface of NDs possesses better efficacy and biocompatibility on oral delivery of poorly soluble drug CUR than pristine and non-covalent coated nanoparticles.
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http://dx.doi.org/10.1208/s12249-020-01721-0DOI Listing
July 2020

In vitro and in vivo studies on the degradation and biosafety of Mg-Zn-Ca-Y alloy hemostatic clip with the carotid artery of SD rat model.

Mater Sci Eng C Mater Biol Appl 2020 Oct 12;115:111093. Epub 2020 May 12.

National Demonstration Center for Experimental Function Materials Education, Tianjin University of Technology, Tianjin 300384, China. Electronic address:

An Mg-Zn-Ca-Y alloy operative clip was developed to overcome the drawbacks of the Ti clips such as ion dissolution inflammation, interference imaging diagnosis, and the potential harm that permanent retention brings to the patient. The structure optimization design of the hemostatic clip was carried out by the finite element numerical simulation method to realize the matching between the structure design and the material properties. Hot extrusion and wire cutting process was used to prepare the Mg-Zn-Ca-Y alloy operative clip. Corrosion degradation behavior of Mg-Zn-Ca-Y alloy in vitro was investigated using electrochemical noise (EN) and immersion test in Simulated body fluid (SBF). The carotid artery of SD rats was clipped using the Mg-Zn-Ca-Y operative clip to evaluate occlusion safety and the complete corrosion degradation behavior and biocompatibility of Mg-Zn-Ca-Y alloy clip in vivo were investigated using micro-computed tomography, histological analysis, and blood biochemical indicators. It was found that the newly designed Mg-Zn-Ca-Y clip can successfully ligate the carotid artery, and no blood leakage occurred after surgery. After eight months, the Mg-Zn-Ca-Y clip degraded utterly. Histological analysis and various blood biochemical parameters in SD rat serum samples collected at different time periods showed no tissue inflammation around the clips.
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http://dx.doi.org/10.1016/j.msec.2020.111093DOI Listing
October 2020

HO, Ca, and K in subsidiary cells of maize leaves are involved in regulatory signaling of stomatal movement.

Plant Physiol Biochem 2020 Jul 7;152:243-251. Epub 2020 May 7.

State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi, 712100, China; State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University, Yangling, Shaanxi, 712100, China. Electronic address:

The stomata of maize (Zea mays) contain a pair of guard cells and a pair of subsidiary cells. To determine whether HO, Ca, and K in subsidiary cells were involved in stomatal movement, we treated four-week-old maize (Zhengdan 958) leaves with HO, diphenylene iodonium (DPI), CaCl, and LaCl. Changes in content and distribution of HO, Ca, and K during stomatal movement were observed. When exogenous HO was applied, Ca increased and K decreased in guard cells, while both ions increased in subsidiary cells, leading to stomatal closure. After DPI treatment, Ca decreased and K increased in guard cells, but both Ca and K decreased in subsidiary cells, resulting in open stomata. Exogenous CaCl increased HO and reduced K in guard cells, while significantly increasing them in subsidiary cells and causing stomatal closure. After LaCl treatment, HO decreased and K increased in guard cells, whereas both decreased in subsidiary cells and stomata became open. Results indicate that HO and Ca correlate positively with each other and with K in subsidiary cells during stomatal movement. Both HO and Ca in subsidiary cells promote an inflow of K, indirectly regulating stomatal closure.
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http://dx.doi.org/10.1016/j.plaphy.2020.04.045DOI Listing
July 2020

Biochemical Mechanisms, Cross-resistance and Stability of Resistance to Metaflumizone in .

Insects 2020 May 15;11(5). Epub 2020 May 15.

Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.

The diamondback moth, (L.) is an important pest of cruciferous crops worldwide. It has developed resistance to many conventional and novel insecticide classes. Metaflumizone belongs to the new chemical class of semicarbazone insecticides. To delay the development of metaflumizone resistance in and to guide insecticide use in the field, the biochemical mechanisms, cross-resistance spectrum, and stability of resistance to metaflumizone were studied in a laboratory-selected resistant strain (metaflu-SEL). Synergism tests with the carboxylesterase inhibitor triphenyl phosphate (TPP), the glutathione S-transferase depletor diethyl maleate (DEM), and the P450 inhibitor piperonyl butoxide(PBO) had no obvious effect on metaflumizone in the metaflu-SEL strain and the susceptible strain (SS) of , with synergism ratios that ranged from 1.02 to 1.86. Biochemical studies revealed that the cytochrome P450-dependent monooxygenase increased only 1.13-fold in the metaflu-SEL strain compared with the UNSEL stain; meanwhile, carboxylesterase and glutathione -transferase activity showed no difference. These results suggest that these detoxification enzymes may be not actively involved in metaflumizone resistance. Furthermore, the metaflu-SEL population showed a moderate level of cross-resistance to indoxacarb (11.63-fold), but only very low cross-resistance to spinosad (1.75-fold), spinetoram (3.52-fold), abamectin (2.81-fold), beta-cypermethrin (0.71-fold), diafenthiuron (0.79-fold), chlorantraniliprole (2.16-fold), BT (WG-001) (3.34-fold), chlorfenapyr (0.49-fold), and chlorfluazuron (0.97-fold). Moreover, metaflumizone resistance decreased from 1087.85- to 1.23-fold in the metaflu-SEL strain after 12 generations without exposure to metaflumizone. These results are useful for formulating insecticide resistance management strategies to control and to delay the development of metaflumizone resistance in the field.
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http://dx.doi.org/10.3390/insects11050311DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7291261PMC
May 2020

Visualization of Ligand-Bound Ectodomain Assembly in the Full-Length Human IGF-1 Receptor by Cryo-EM Single-Particle Analysis.

Structure 2020 05 9;28(5):555-561.e4. Epub 2020 Apr 9.

Department of Biology, Southern University of Science and Technology, Shenzhen 518055, China; Institute of Systems Biology, Shenzhen Bay Laboratory, Peking University Shenzhen Graduate School, Shenzhen 518055, China; Joint Laboratory for Infectious Disease Prevention and Control, Hygienic Section of Longhua Center for Disease Control and Prevention, Shenzhen 518109, China. Electronic address:

Tyrosine kinase receptor of insulin-like growth factor 1 receptor (IGF-1R) and insulin receptor (IR) bind to hormones, such as insulin, IGF-1, and IGF-2, and transduces the signals across the cell membrane. However, the complete structure of the receptor and the signal transduction mechanism remains unclear. Here, we report the cryo-EM structure of the ligand-bound ectodomain in the full-length human IGF-1R. We reconstructed the IGF-1R/insulin complex at 4.7 Å and the IGF-1R/IGF-1 complex at 7.7 Å. Our structures reveal that only one insulin or one IGF-1 molecule binds to and activates the full-length human IGF-1R receptor.
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http://dx.doi.org/10.1016/j.str.2020.03.007DOI Listing
May 2020

Development of Improved Double-Nanobody Sandwich ELISAs for Human Soluble Epoxide Hydrolase Detection in Peripheral Blood Mononuclear Cells of Diabetic Patients and the Prefrontal Cortex of Multiple Sclerosis Patients.

Anal Chem 2020 05 27;92(10):7334-7342. Epub 2020 Apr 27.

Department of Entomology and Nematology and UCD Comprehensive Cancer Center, University of California, Davis, California 95616, United States.

Nanobodies have been progressively replacing traditional antibodies in various immunological methods. However, the use of nanobodies as capture antibodies is greatly hampered by their poor performance after passive adsorption to polystyrene microplates, and this restricts the full use of double nanobodies in sandwich enzyme-linked immunosorbent assays (ELISAs). Herein, using the human soluble epoxide hydrolase (sEH) as a model analyte, we found that both the immobilization format and the blocking agent have a significant influence on the performance of capture nanobodies immobilized on polystyrene and the subsequent development of double-nanobody sandwich ELISAs. We first conducted epitope mapping for pairing nanobodies and then prepared a horseradish-peroxidase-labeled nanobody using a mild conjugation procedure as a detection antibody throughout the work. The resulting sandwich ELISA using a capture nanobody (A9, 1.25 μg/mL) after passive adsorption and bovine serum albumin (BSA) as a blocking agent generated a moderate sensitivity of 0.0164 OD·mL/ng and a limit of detection (LOD) of 0.74 ng/mL. However, the introduction of streptavidin as a linker to the capture nanobody at the same working concentration demonstrated a dramatic 16-fold increase in sensitivity (0.262 OD·mL/ng) and a 25-fold decrease in the LOD for sEH (0.03 ng/mL). The streptavidin-bridged double-nanobody ELISA was then successfully applied to tests for recovery, cross-reactivity, and real samples. Meanwhile, we accidentally found that blocking with skim milk could severely damage the performance of the capture nanobody by an order of magnitude compared with BSA. This work provides guidelines to retain the high effectiveness of the capture nanobody and thus to further develop the double-nanobody ELISA for various analytes.
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http://dx.doi.org/10.1021/acs.analchem.0c01115DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7744119PMC
May 2020

Bifunctional Ultrathin PCBM Enables Passivated Trap States and Cascaded Energy Level toward Efficient Inverted Perovskite Solar Cells.

ACS Appl Mater Interfaces 2020 Apr 14;12(17):20103-20109. Epub 2020 Apr 14.

Department of Materials Science and Engineering, Southern University of Science and Technology (SUSTech), Shenzhen 518055, P. R. China.

Inverted perovskite solar cells (PSCs) with a C framework are known for their common drawback of low power conversion efficiency (PCE) of <20% because of nonradiative recombination and inefficient charge transport at their perovskite interfaces. Here, we report an ultrathin [6,6]-phenyl-C-butyric acid methyl ester (PCBM) as a cap layer on perovskite films to overcome this issue. Such a functional cap layer efficiently passivates trap states and establishes a gradient energy level alignment onto perovskite, facilitating the efficient charge transfer and extraction. The as-fabricated inverted PSCs capped with such ultrathin PCBM exhibit a record PCE of 20.07%. After the storage under a N atmosphere for more than 500 h, the PCE of PSCs retains over 85% of its initial level. Our work provides an effective method to upgrade inverted PSCs with the C framework with improved efficiency and stability.
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http://dx.doi.org/10.1021/acsami.0c02837DOI Listing
April 2020

Molecular Mechanism for Azeotrope Formation in Ethanol/Benzene Binary Mixtures through Gibbs Ensemble Monte Carlo Simulation.

J Phys Chem B 2020 Apr 13;124(16):3371-3386. Epub 2020 Apr 13.

Department of Chemical Engineering, McMaster Universtiy, Hamilton, Ontario L8S 4L7, Canada.

Azeotropes have been studied for decades due to the challenges they impose on separation processes but fundamental understanding at the molecular level remains limited. Although molecular simulation has demonstrated its capability of predicting mixture vapor-liquid equilibrium (VLE) behaviors, including azeotropes, its potential for mechanistic investigation has not been fully exploited. In this study, we use the united atom transferable potentials for phase equilibria (TraPPE-UA) force field to model the ethanol/benzene mixture, which displays a positive azeotrope. Gibbs ensemble Monte Carlo (GEMC) simulation is performed to predict the VLE phase diagram, including an azeotrope point. The results accurately agree with experimental measurements. We argue that the molecular mechanism of azeotrope formation cannot be fully understood by studying the mixture liquid-state stability at the azeotrope point alone. Rather, azeotrope occurrence is only a reflection of the changing relative volatility between the two components over a much wider composition range. A thermodynamic criterion is thus proposed on the basis of the comparison of partial excess Gibbs energy between the components. In the ethanol/benzene system, molecular energetics shows that with increasing ethanol mole fraction, its volatility initially decreases but later plateaus, while benzene volatility is initially nearly constant and only starts to decrease when its mole fraction is low. Analysis of the mixture liquid structure, including a detailed investigation of ethanol hydrogen-bonding configurations at different composition levels, reveals the underlying molecular mechanism for the changing volatilities responsible for the azeotrope.
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http://dx.doi.org/10.1021/acs.jpcb.9b12013DOI Listing
April 2020

Asymmetric Iodonio-[3,3]-Sigmatropic Rearrangement to Access Chiral α-Aryl Carbonyl Compounds.

J Am Chem Soc 2020 04 19;142(15):6884-6890. Epub 2020 Mar 19.

Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University, Jinhua 321004, China.

Here we describe an asymmetric [3,3]-sigmatropic rearrangement of aryl iodanes that enables the enantioselective α-arylation of chiral 2-oxazolines, thereby producing valuable chiral α-aryl carbonyl compounds. The success of this protocol hinges on the selective assembly of aryl iodanes with 2-oxazolines and the smooth deprotonation of the in situ-generated iodonium-imine species. The nearly neutral and mild conditions of the reaction allow it to tolerate a wide variety of functional groups. Moreover, the remaining iodine atom in the products not only provides a versatile platform for further elaboration of such molecules but also supplies the asymmetric hypervalent iodine chemistry with a new class of chiral scaffolds.
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http://dx.doi.org/10.1021/jacs.0c00783DOI Listing
April 2020

Highly Robust Non-Noble Alkaline Hydrogen-Evolving Electrocatalyst from Se-Doped Molybdenum Disulfide Particles on Interwoven CoSe Nanowire Arrays.

Small 2020 Apr 4;16(13):e1906629. Epub 2020 Mar 4.

Synergetic Innovation Center for Quantum Effects and Applications, Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, Hunan, China.

Developing efficient non-noble and earth-abundant hydrogen-evolving electrocatalysts is highly desirable for improving the energy efficiency of water splitting in base. Molybdenum disulfide (MoS ) is a promising candidate, but its catalytic activity is kinetically retarded in alkaline media due to the unfavorable water adsorption and dissociation feature. A heterogeneous electrocatalyst is reported that is constructed by selenium-doped MoS (Se-MoS ) particles on 3D interwoven cobalt diselenide (CoSe ) nanowire arrays that drives the hydrogen evolution reaction (HER) with fast reaction kinetics in base. The resultant Se-MoS /CoSe hybrid exhibits an outstanding catalytic HER performance with extremely low overpotentials of 30 and 93 mV at 10 and 100 mA cm in base, respectively, which outperforms most of the inexpensive alkaline HER catalysts, and is among the best alkaline catalytic activity reported so far. Moreover, this hybrid catalyst shows exceptional catalytic performance with very low overpotentials of 84 and 95 mV at 10 mA cm in acidic and neutral electrolytes, respectively, implying robust pH universality of this hybrid catalyst. This work may provide new inspirations for the development of high-performance MoS -based HER electrocatalysts in unfavorable basic media for promising catalytic applications.
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http://dx.doi.org/10.1002/smll.201906629DOI Listing
April 2020