Publications by authors named "Sheng Ye"

311 Publications

Direct observation of surface charge redistribution in active nanoscale conducting channels by Kelvin Probe Force Microscopy.

Nanotechnology 2021 Apr 30. Epub 2021 Apr 30.

Electronics and Computer Science, University of Southampton, Southampton, Hampshire, UNITED KINGDOM OF GREAT BRITAIN AND NORTHERN IRELAND.

Surface-exposed uniformly doped Silicon-on-Insulator (SOI) channels are fabricated to evaluate the accuracy of Kelvin Probe Force Microscopy (KPFM) measured surface potential and reveals the role of surface charge on the exposed channel operated in the ambient environment. First, the quality of the potential profile probed in the vacuum environment is assessed by the consistency of converted resistivity from KPFM result to the resistivity extracted by the other three methods. Second, in contrast to the simulated and vacuum surface potential profile and image, the ambient surface potential is bent excessively at the terminals of the channel. The excessive bending can be explained by the movement of surface charge under the drive of geometry induced strong local electric field from the channel and results in non-uniform distribution. The dynamic movement of surface charges is proved by the observation of time-dependent potential drift in the ambient measurement. The result suggests the surface charge effect should be taken into account of the measurement of the surface potential in the ambient environment and the design of charge sensitive devices whose surfaces are exposed to air or in ambient conditions in their operation.
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http://dx.doi.org/10.1088/1361-6528/abfd55DOI Listing
April 2021

The Assembly Switch Mechanism of FtsZ Filament Revealed by All-Atom Molecular Dynamics Simulations and Coarse-Grained Models.

Front Microbiol 2021 30;12:639883. Epub 2021 Mar 30.

Life Sciences Institute, Zhejiang University, Hangzhou, China.

Bacterial cytoskeletal protein FtsZ binds and hydrolyzes GTP, and assembles into dynamic filaments that are essential for cell division. Here, we used a multi-scale computational strategy that combined all-atom molecular dynamics (MD) simulations and coarse-grained models to reveal the conformational dynamics of assembled FtsZ. We found that the top end of a filament is highly dynamic and can undergo T-to-R transitions in both GTP- and GDP-bound states. We observed several subcategories of nucleation related dimer species, which leading to a feasible nucleation pathway. In addition, we observed that FtsZ filament exhibits noticeable amounts of twisting, indicating a substantial helicity of the FtsZ filament. These results agree with the previously models and experimental data. Anisotropy network model (ANM) analysis revealed a polymerization enhanced assembly cooperativity, and indicated that the cooperative motions in FtsZ are encoded in the structure. Taken together, our study provides a molecular-level understanding of the diversity of the structural states of FtsZ and the relationships among polymerization, hydrolysis, and cooperative assembly, which should shed new light on the molecular basis of FtsZ's cooperativity.
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http://dx.doi.org/10.3389/fmicb.2021.639883DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8042166PMC
March 2021

Lactobionic acid-modified chitosan thermosensitive hydrogels that lift lesions and promote repair in endoscopic submucosal dissection.

Carbohydr Polym 2021 Jul 27;263:118001. Epub 2021 Mar 27.

National Engineering Research Center for Biomaterials, Sichuan University, 29 Wangjiang Road, Chengdu, Sichuan, China.

To develop a biomaterial to lift the lesion and promote wound healing in endoscopic submucosal dissection (ESD), we used lactobionic acid (LA) to improve the water solubility of chitosan (CS) and prepared a new three-phase hydrogel system with lactobionic acid-modified chitosan/chitosan/β-glycerophosphate (CSLA/CS/GP). The results indicated that the hydrogel retains temperature-sensitive properties, and CSLA obviously improved the low-temperature fluidity of the hydrogel precursor solution, enabling injection of the hydrogel by endoscopic needle. The mechanical strength and bio-adhesion of the hydrogels were also improved by the addition of CSLA and the hydrogels could be maintained in acidic environment for a few days and exhibit greater protection of cells. The CSLA/CS/GP hydrogels show good cytocompatibility. The heights of cushions elevated by CSLA/CS/GP hydrogels remained ∼ 60 % 2 h post-injection in porcine stomach models. Given the unique characteristics of these materials, the CSLA/CS/GP thermo-sensitive hydrogel is a promising intraoperative biomaterial in ESD.
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http://dx.doi.org/10.1016/j.carbpol.2021.118001DOI Listing
July 2021

Modular Construction of Prussian Blue Analog and TiO Dual-Compartment Janus Nanoreactor for Efficient Photocatalytic Water Splitting.

Adv Sci (Weinh) 2021 Apr 16;8(7):2001987. Epub 2021 Feb 16.

State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences, and Dalian National Laboratory for Clean Energy 457 Zhongshan Road Dalian 116023 P. R. China.

Janus structures that include different functional compartments have attracted significant attention due to their specific properties in a diverse range of applications. However, it remains challenge to develop an effective strategy for achieving strong interfacial interaction. Herein, a Janus nanoreactor consisting of TiO 2D nanocrystals integrated with Prussian blue analog (PBA) single crystals is proposed and synthesized by mimicking the planting process. In situ etching of PBA particles induces nucleation and growth of TiO nanoflakes onto the concave surface of PBA particles, and thus enhances the interlayer interaction. The anisotropic PBA-TiO Janus nanoreactor demonstrates enhanced photocatalytic activities for both water reduction and oxidation reactions compared with TiO and PBA alone. As far as it is known, this is the first PBA-based composite that serves as a bifunctional photocatalyst for solar water splitting. The interfacial structure between two materials is vital for charge separation and transfer based on the spectroscopic studies. These results shed light on the elaborate construction of Janus nanoreactor, highlighting the important role of interfacial design at the microscale level.
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http://dx.doi.org/10.1002/advs.202001987DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024990PMC
April 2021

Laparoscopic versus open radical antegrade modular pancreatosplenectomy for pancreatic cancer: a single-institution comparative study.

Gland Surg 2021 Mar;10(3):1057-1066

Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China.

Background: Laparoscopic distal pancreatosplenectomy is an effective and safe surgical modality for treating benign and borderline distal pancreatic tumors, but rarely for pancreatic cancer. This study aimed to compare the feasibility and safety of laparoscopic and open radical antegrade modular pancreatosplenectomy for pancreatic cancer.

Methods: Fifty-one patients with pancreatic cancer who underwent radical antegrade modular pancreatosplenectomy at Ningbo Medical Center Lihuili Hospital between January 2014 and July 2018 were enrolled. 20 patients underwent laparoscopic radical antegrade modular pancreatosplenectomy and 31 patients received open radical antegrade modular pancreatosplenectomy. Postoperative and short-term outcomes of the two groups of patients were analyzed.

Results: The mean operation time, length of postoperative hospital stay, and overall postoperative morbidity were similar in the two groups (P>0.05). The laparoscopic radical antegrade modular pancreatosplenectomy group lost less blood (252.5±198.3 472.6±428.0 mL, P=0.037) and had lower transfusion rates (10.0% 35.4%, P=0.041) than the open radical antegrade modular pancreatosplenectomy group. The laparoscopic group also had statistically significantly earlier passing of first flatus (2.5±0.8 3.2±1.2 days, P=0.028) and first oral intake (2.9±1.0 3.7±1.6 days, P=0.042). Furthermore, the rates of postoperative pancreatic fistula (45.0% 32.3%) and overall complications (70.0% 74.2%) were not statistically difference between the two groups. The survival rates at 6 months, 1 year, and 2 years after surgery were not statistically difference between the laparoscopic and open groups (94.4% 93.5, 67.0% 78.0%, and 50.2% 38.3%, respectively).

Conclusions: The results of this study show that laparoscopic radical antegrade modular pancreatosplenectomy is feasible and safe for the treatment of pancreatic cancer.
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http://dx.doi.org/10.21037/gs-21-56DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8033082PMC
March 2021

Luminescence and Energy Transfer of Color-Tunable YMgAlSiO:Eu,Ce Phosphors.

Inorg Chem 2021 Apr 3;60(8):5908-5916. Epub 2021 Apr 3.

College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, China.

Color-tunable phosphors can be obtained through codoping strategies and energy transfer regulation. Ce and Eu are the most common and effective activator ions used in phosphor materials. However, the energy transfer from Eu to Ce is rarely reported. In this work, YMgAlSiO(YMAS):Eu,Ce phosphors were successfully synthesized, which was confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Rietveld refinement, scanning electron microscopy (SEM) and element mapping images, and spectral information. The luminescent color of YMAS:Eu,Ce phosphors could be tuned from blue to cyan to light green to yellow-green and finally to green-yellow, which was achieved by adjusting the energy transfer between different dopants. The energy transfer from Eu to Ce was confirmed by photoluminescence spectra and fluorescence decay curves. Within the experimental gradient, the energy transfer efficiency could reach up to 48%. At 373 K, the YMgAlSiO:0.01Eu,0.01Ce (YMAS:0.01Eu,0.01Ce) phosphor exhibited a total integral emission loss of only 8%, and the emission peak intensity decreased to 95%, indicating the excellent thermal stability. The white light-emitting diode (WLED) fabricated by the YMAS:0.01Eu,0.01Ce phosphor has the same level correlated color temperature (CCT = 5841 K), greatly improved color rendering index ( = 87.8), and higher quality white light color (CIE = (0.3258, 0.3214)) than the WLED made by the YMAS:0.01Eu phosphor, indicating that the performance of the phosphor was significantly improved by introducing Ce. This work provides an effective guide for the design and development of highly efficient color-tunable phosphors involving energy transfer from Eu to Ce in some specific materials, such as garnet structures.
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http://dx.doi.org/10.1021/acs.inorgchem.1c00317DOI Listing
April 2021

Nitrogen-doped porous carbon-encapsulated copper composite for efficient reduction of 4-nitrophenol.

J Colloid Interface Sci 2021 Jul 10;594:254-264. Epub 2021 Mar 10.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Science, 568 Zhongshan Road, Dalian 116023, China. Electronic address:

Developing low-cost non-precious metals as efficient catalysts for the reduction of toxic 4-nitrophenol (4-NP) to useful 4-aminophenol (4-AP) have received increasing attention in recent years. Herein, a novel and efficient Cu-based catalyst Cu/CuO@CN (carbon doped with nitrogen) was prepared via a facile method from pyrolysis of bi-ligand MOFs material Cu(BDC)(BPY) (BDC = p-Phthalic acid, BPY = 4,4'-bipyridyl) in Ar atmosphere. Characterization results revealed that N doping in carbon matrix favors the development of mesoporous structure, the formation of more defect sites in carbon matrix, better dispersion of Cu/CuO nano particles, and maintenance of Cu species in metallic Cu state (the active site), all of which contribute to a superior catalytic activity for 4-NP reduction with a pseudo-first-order rate constant as high as 0.126 s (the molar ratio of NaBH to 4-NP is 400), nearly 11 times higher than its counterpart Cu/CuO@C without N doping (0.011 s). The activation energy for 4-NP reduction to 4-AP catalyzed by Cu/CuO@CN was determined as 55.6 kJ mol (the molar ratio of NaBH to 4-NP is 100). In addition, Cu/CuO@CN showed excellent reusability in successive 6 cycles. The facile synthesis and superior catalytic activity make Cu/CuO@CN a promising catalyst in industrial applications for many other similar reaction systems.
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http://dx.doi.org/10.1016/j.jcis.2021.03.020DOI Listing
July 2021

Derivates variation of phenylalanine as a model disinfection by-product precursor during long term chlorination and chloramination.

Sci Total Environ 2021 Jun 28;771:144885. Epub 2021 Jan 28.

Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA. Electronic address:

Dissolved nitrogenous organic matter in water can contain precursors of disinfection by-products (DBPs), especially nitrogenous DBPs (N-DBPs). Amino acids are ubiquitous as dissolved nitrogenous organic matter in source water and can pass through drinking water treatment processes to react with disinfectants in finished water and in the distribution system. Phenylalanine (Phe) was selected as a model amino acid precursor to investigate its derived DBPs and their variations during a chlorination regime that simulated water distribution with residue chlorine. The 7-day DBPs formation potential (DBPsFP) test with chlorine revealed chlorination by-products of phenylalanine including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), and halonitromethanes (HNMs), but not trichloronitromethane (TCNM) which was a significant N-DBP detected during the first 48 h of chlorine contact. The formation of most carbonaceous DBPs (C-DBPs) increased with chlorination time; however N-DBPs and non-chlorinated byproducts of phenylacetonitrile and phenylacetaldehyde reached their highest concentration after 2 h of reaction, and then gradually decreased until below detection after 7 days. The chlorination influencing factors indicated that light enhanced the peak yield of DBPs; the pH value showed different influences associated with corresponding DBPs; and the presence of bromide ions (Br) generated a variety of bromine-containing DBPs. The DBPsFP test with chloramine reduced C-DBPs generation to about 1/3 of the level observed for chlorine disinfection and caused an increase in dichloroacetonitrile. Surveillance of DBPs during drinking water distribution to consumers should consider the varying contact times with disinfectants to accurately profile the types and concentrations of C-DBPs and N-DBPs present in drinking water.
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http://dx.doi.org/10.1016/j.scitotenv.2020.144885DOI Listing
June 2021

Violation of the Relationship in the Lattice Thermal Conductivity of MgSb with Locally Asymmetric Vibrations.

Research (Wash D C) 2020 30;2020:4589786. Epub 2020 Nov 30.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.

Most crystalline materials follow the guidelines of temperature-dependent lattice thermal conductivity ( ) at elevated temperatures. Here, we observe a weak temperature dependence of in MgSb, from theory and from measurements, based on a comprehensive study combining molecular dynamics calculations and experimental measurements on single crystal MgSb. These results can be understood in terms of the so-called "phonon renormalization" effects due to the strong temperature dependence of the interatomic force constants (IFCs). The increasing temperature leads to the frequency upshifting for those low-frequency phonons dominating heat transport, and more importantly, the phonon-phonon interactions are weakened. In-depth analysis reveals that the phenomenon is closely related to the temperature-induced asymmetric movements of Mg atoms within MgSb tetrahedron. With increasing temperature, these Mg atoms tend to locate at the areas with relatively low force in the force profile, leading to reduced effective 3-order IFCs. The locally asymmetrical atomic movements at elevated temperatures can be further treated as an indicator of temperature-induced variations of IFCs and thus relatively strong phonon renormalization. The present work sheds light on the fundamental origins of anomalous temperature dependence of in thermoelectrics.
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http://dx.doi.org/10.34133/2020/4589786DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7877392PMC
November 2020

Porous Carbon Nitride Thin Strip: Precise Carbon Doping Regulating Delocalized π-Electron Induces Elevated Photocatalytic Hydrogen Evolution.

Small 2021 Mar 18;17(11):e2006622. Epub 2021 Feb 18.

State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, P. R. China.

The photocatalytic efficiency of polymeric carbon nitride is hampered by high carrier recombination rate and low charge transfer. Herein, these issues are addressed by constructing 1D strip-like carbon nitride with a large π-electron conjugated system from carbon-doping, realizing the synchronization control of its electronic structure and morphology. Nicotinic acid, a monomer with the carboxyl group and pyridine ring, and melamine are selected for assembling the strip-like supramolecular via hydrogen bond under hydrothermal process. Both peripheral pyridine unit and hydrogen bond have significant effect on self-assembly process of nicotinic acid and melamine along one dimension to form a strip-like precursor. Subsequently, 1D thin porous strip-like carbon nitride is obtained by calcination treatment of precursor. The as-prepared 1D strip-like carbon nitride with effective π delocalization from carbon-doping and porous structure can accelerate charges and mass transfer and provide extra active sites. Both theoretical and experimental results demonstrate that carbon doping (pyridine heterocycle) narrows the bandgap via manipulating the band position and increases the π electron density. Thus, the 1D porous thin strip-like carbon nitride realizes compelling hydrogen evolution rate (126.2 µmol h ), far beyond (≈18 fold) the value of polymeric carbon nitride (PCN) (7.2 µmol h ) under visible light irradiation.
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http://dx.doi.org/10.1002/smll.202006622DOI Listing
March 2021

Comparison of acute pneumonia caused by SARS-COV-2 and other respiratory viruses in children: a retrospective multi-center cohort study during COVID-19 outbreak.

Mil Med Res 2021 02 16;8(1):13. Epub 2021 Feb 16.

Department of Neonatology, Children's Hospital of Chongqing Medical University/Ministry of Education Key Laboratory of Child/Development and Disorders/National Clinical Research Center for Child Health and Disorders/Chongqing Key Laboratory of Pediatrics, Chongqing, 400014, China.

Background: Until January 18, 2021, coronavirus disease-2019 (COVID-19) has infected more than 93 million individuals and has caused a certain degree of panic. Viral pneumonia caused by common viruses such as respiratory syncytial virus, rhinovirus, human metapneumovirus, human bocavirus, and parainfluenza viruses have been more common in children. However, the incidence of COVID-19 in children was significantly lower than that in adults. The purpose of this study was to describe the clinical manifestations, treatment and outcomes of COVID-19 in children compared with those of other sources of viral pneumonia diagnosed during the COVID-19 outbreak.

Methods: Children with COVID-19 and viral pneumonia admitted to 20 hospitals were enrolled in this retrospective multi-center cohort study. A total of 64 children with COVID-19 were defined as the COVID-19 cohort, of which 40 children who developed pneumonia were defined as the COVID-19 pneumonia cohort. Another 284 children with pneumonia caused by other viruses were defined as the viral pneumonia cohort. The epidemiologic, clinical, and laboratory findings were compared by Kolmogorov-Smirnov test, t-test, Mann-Whitney U test and Contingency table method. Drug usage, immunotherapy, blood transfusion, and need for oxygen support were collected as the treatment indexes. Mortality, intensive care needs and symptomatic duration were collected as the outcome indicators.

Results: Compared with the viral pneumonia cohort, children in the COVID-19 cohort were mostly exposed to family members confirmed to have COVID-19 (53/64 vs. 23/284), were of older median age (6.3 vs. 3.2 years), and had a higher proportion of ground-glass opacity (GGO) on computed tomography (18/40 vs. 0/38, P < 0.001). Children in the COVID-19 pneumonia cohort had a lower proportion of severe cases (1/40 vs. 38/284, P = 0.048), and lower cases with high fever (3/40 vs. 167/284, P < 0.001), requiring intensive care (1/40 vs. 32/284, P < 0.047) and with shorter symptomatic duration (median 5 vs. 8 d, P < 0.001). The proportion of cases with evaluated inflammatory indicators, biochemical indicators related to organ or tissue damage, D-dimer and secondary bacterial infection were lower in the COVID-19 pneumonia cohort than those in the viral pneumonia cohort (P < 0.05). No statistical differences were found in the duration of positive PCR results from pharyngeal swabs in 25 children with COVID-19 who received antiviral drugs (lopinavir-ritonavir, ribavirin, and arbidol) as compared with duration in 39 children without antiviral therapy [median 10 vs. 9 d, P = 0.885].

Conclusion: The symptoms and severity of COVID-19 pneumonia in children were no more severe than those in children with other viral pneumonia. Lopinavir-ritonavir, ribavirin and arbidol do not shorten the duration of positive PCR results from pharyngeal swabs in children with COVID-19. During the COVID-19 outbreak, attention also must be given to children with infection by other pathogens infection.
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http://dx.doi.org/10.1186/s40779-021-00306-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7886299PMC
February 2021

Can Industrial Collaborative Agglomeration Reduce Haze Pollution? City-Level Empirical Evidence from China.

Int J Environ Res Public Health 2021 02 7;18(4). Epub 2021 Feb 7.

Institute of Central China Development, Wuhan University, Wuhan 430072, China.

We analyze the mechanism for industrial co-agglomeration in Chinese 283 cities to affect haze pollution from 2003 to 2016 and examine the possible mediating effects of urbanization and energy structure between haze pollution and industrial co-agglomeration, finally obtaining the following results. First, industrial co-agglomeration and haze pollution across China, including central and eastern regions keep a typical inverted U-shaped curve relationship. That is, industrial co-agglomeration first promotes haze pollution and then restrains it. However, the impact of industrial co-agglomeration on haze pollution in western China is still on the left side of the inverted U-shaped curve, reflecting a promotion effect. Second, industrial co-agglomeration has a significant spatial spillover effect on haze pollution. Additionally, industrial co-agglomeration can promote haze pollution in local regions but inhibit it in surrounding regions in both the short and long run. In contrast, when the industrial co-agglomeration index exceeds the inflection point (3.6531), it benefits the reduction of haze pollution in local regions, while not being conducive to it in the neighboring regions. Third, industrial co-agglomeration can affect haze pollution through urbanization and energy structure, that is, urbanization and energy structure play an intermediary role between them.
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http://dx.doi.org/10.3390/ijerph18041566DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7915316PMC
February 2021

SiO:Tb@LuO:Eu Core-Shell Phosphors: Interfacial Energy Transfer for Enhanced Multicolor Luminescence.

Inorg Chem 2021 Feb 22;60(4):2542-2552. Epub 2021 Jan 22.

College of Chemistry, Jilin University, Changchun 130012, P. R. China.

Uniform and well-dispersed SiO:%Tb@LuO:%Eu core-shell spherical phosphors were synthesized via a solvothermal method followed by a subsequent calcination process. The structure, phase composition, and morphology of the samples were studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results showed that the LuO:Eu layer was evenly coated on the surface of SiO:Tb spheres and the shell thickness was about 45-65 nm. The PL spectra and fluorescence lifetimes of the samples were further studied. It was proved that the multicolor luminescence of the samples could be realized by changing the doping concentration ratio of Eu or by changing the excitation wavelengths. Compared with SiO@LuO:3%Tb,6%Eu, SiO:3%Tb@LuO:6%Eu showed stronger luminescence intensity, longer fluorescence lifetime, and higher energy transfer efficiency, which was attributed to the effective interfacial energy transfer, and the interfacial energy transfer mechanism from Tb to Eu was a dipole-dipole interaction mechanism. The XPS results indicated that the sample contained a high content of Si-O-Lu bonds, which proved that there was a strong interaction between the SiO core and the LuO shell, making the interfacial energy transfer possible. These results provided a new idea for luminescence enhancement and multicolor luminescence.
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http://dx.doi.org/10.1021/acs.inorgchem.0c03445DOI Listing
February 2021

Transplanting -silenced bone marrow mesenchymal stem cells promote neurological function recovery in TBI mice.

Aging (Albany NY) 2020 12 19;13(2):2822-2850. Epub 2020 Dec 19.

Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China.

Bone marrow mesenchymal stem cells (BMMSCs)-based therapy has emerged as a promising novel therapy for Traumatic Brain Injury (TBI). However, the therapeutic quantity of viable implanted BMMSCs necessary to initiate efficacy is still undetermined. Increased oxidative stress following TBI, which leads to the activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase signaling pathway, has been implicated in accounting for the diminished graft survival and therapeutic effect. To prove this assertion, we silenced the expression of NADPH subunits (p22-phox, p47-phox, and p67-phox) and small GTPase Rac1 in BMMSCs using shRNA. Our results showed that silencing these proteins significantly reduced oxidative stress and cell death/apoptosis, and promoted implanted BMMSCs proliferation after TBI. The most significant result was however seen with silencing, which demonstrated decreased expression of apoptotic proteins, enhanced survival ratio, reduction in TBI lesional volume and significant improvement in neurological function post shRac1-BMMSCs transplantation. Additionally, two RNA-seq hub genes ( and ) were identified to play critical roles in shRac1-mediated cell survival. In summary, we propose that knockdown of gene could significantly boost cell survival and promote the recovery of neurological functions after BMMSCs transplantation in TBI mice.
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http://dx.doi.org/10.18632/aging.202334DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7880331PMC
December 2020

Structures and an activation mechanism of human potassium-chloride cotransporters.

Sci Adv 2020 Dec 11;6(50). Epub 2020 Dec 11.

Department of Biophysics, and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310058, China.

Potassium-chloride cotransporters KCC1 to KCC4 mediate the coupled export of potassium and chloride across the plasma membrane and play important roles in cell volume regulation, auditory system function, and γ-aminobutyric acid (GABA) and glycine-mediated inhibitory neurotransmission. Here, we present 2.9- to 3.6-Å resolution structures of full-length human KCC2, KCC3, and KCC4. All three KCCs adopt a similar overall architecture, a domain-swap dimeric assembly, and an inward-facing conformation. The structural and functional studies reveal that one unexpected N-terminal peptide binds at the cytosolic facing cavity and locks KCC2 and KCC4 at an autoinhibition state. The C-terminal domain (CTD) directly interacts with the N-terminal inhibitory peptide, and the relative motions between the CTD and the transmembrane domain (TMD) suggest that CTD regulates KCCs' activities by adjusting the autoinhibitory effect. These structures provide the first glimpse of full-length structures of KCCs and an autoinhibition mechanism among the amino acid-polyamine-organocation transporter superfamily.
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http://dx.doi.org/10.1126/sciadv.abc5883DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7732191PMC
December 2020

Cryo-EM structures of human calcium homeostasis modulator 5.

Cell Discov 2020 Nov 10;6(1):81. Epub 2020 Nov 10.

Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang 310058, China.

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http://dx.doi.org/10.1038/s41421-020-00228-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652935PMC
November 2020

A single-phase full-visible-spectrum phosphor for white light-emitting diodes with ultra-high color rendering.

Dalton Trans 2020 Dec 7;49(48):17796-17805. Epub 2020 Dec 7.

College of Chemistry, Jilin University, Qianjin Street 2699, Changchun 130012, China.

Excellent luminous performance and high color rendering are the keys to white light-emitting diode (WLED) illumination. This work reports a single-phase full-visible-spectrum YMgAlSiO(YMAS):Eu,Mn phosphor for WLEDs with ultra-high color rendering. The luminescence of a single Mn doped YMAS phosphor is very weak due to the spin-forbidden transition of Mn, while it can be dramatically enhanced in the YMAS:Eu,Mn system through efficient energy transfer from the sensitizer Eu. Meanwhile, the luminescent color of this phosphor can be tuned from cyan to cold white, to warm white, and finally close to the yellow region by controlling the activator concentration and energy transfer process. Its good thermal and chromaticity stability meet the requirements of application in WLEDs. Its stable photochromic performance at different excitation wavelengths (365-395 nm) indicates that it can be used in different ultraviolet chips. The YMAS:0.03Eu,0.30Mn phosphor-converted WLED achieves an ultra-high color rendering index (Ra = 93.3), near-standard chromaticity coordinates (CIE = (0.3343, 0.3388)) and a suitable correlated color temperature (CCT = 5417 K).
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http://dx.doi.org/10.1039/d0dt03797dDOI Listing
December 2020

Feasibility of T1 mapping with histogram analysis for the diagnosis and staging of liver fibrosis: Preclinical results.

Magn Reson Imaging 2021 02 24;76:79-86. Epub 2020 Nov 24.

Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou & Changzhou First People's Hospital, Jiangsu 213200, China. Electronic address:

Purpose: To compare the diagnostic accuracy of parameters derived from the histogram analysis of precontrast, 10-min hepatobiliary phase (HBP) and 20-min HBP T1 maps for staging liver fibrosis (LF).

Methods: LF was induced in New Zealand white rabbits by subcutaneous injections of carbon tetrachloride for 4-16 weeks (n = 120), and 20 rabbits injected with saline served as controls. Precontrast, 10-min and 20-min HBP modified Look-Locker inversion recovery (MOLLI) T1 mapping was performed. Histogram analysis of T1 maps was performed, and the mean, median, skewness, kurtosis, entropy, inhomogeneity and 10th/25th/75th/90th percentiles of T1, T1 and T1 were derived. Quantitative histogram parameters were compared. For significant parameters, further receiver operating characteristic (ROC) analyses were performed to evaluate the potential diagnostic performance in differentiating LF stages.

Results: Finally, 17, 20, 21, 21 and 20 rabbits were included for the F0, F1, F2, F3, and F4 pathological grades of fibrosis, respectively. The mean/75th of T1, entropy of T1 and entropy/mean/median/10th of T1 demonstrated a significant good correlation with the LF stage (|r| = 0.543-0.866, all P < 0.05). The 75th of T1, entropy, and entropy were the three most reliable imaging markers in reflecting the stage of LF. The area under the ROC curve of entropy was larger than that of entropy (P < 0.05 for LF ≥ F2, ≥F3, and ≥ F4) and the 75th of T1 (P < 0.05 for LF ≥ F2 and ≥ F3) for staging LF.

Conclusion: Magnetic resonance histogram analysis of T1 maps, particularly the entropy derived from 20-min HBP T1 mapping, is promising for predicting the LF stage.
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http://dx.doi.org/10.1016/j.mri.2020.11.006DOI Listing
February 2021

Elevated blood urea nitrogen is associated with recurrence of post-operative chronic subdural hematoma.

BMC Neurol 2020 Nov 10;20(1):411. Epub 2020 Nov 10.

Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, China.

Background: Chronic subdural hematoma (CSDH) is fundamentally treatable with about a 2-31% recurrence rate. Recently, there has been renewed interest in the association between Blood Urea Nitrogen (BUN) and intracranial lesion. Therefore, this paper attempts to show the relationship between BUN and CSDH recurrence.

Methods: A total of 653 CSDH cases with Burr-hole Irrigation (BHI) were enrolled from December 2014 to April 2019. The analyzed parameters included age, gender, comorbidities, laboratory investigations, medication use and hematoma location. The cases were divided into recurrence and non-recurrence groups while postoperative BUN concentration was further separated into quartiles (Q1 ≤ 4.0 mmol/L, 4.0 < Q2 ≤ 4.9 mmol/L, 4.9 < Q3 ≤ 6.4 mmol/L, Q4 > 6.4 mmol/L). Restricted cubic spline regressions and logistic regression models were performed to estimate the effect of BUN on CSDH recurrence.

Results: CSDH recurrence was observed in 96 (14.7%) cases. Significant distinctions were found between recurrence and non-recurrence groups in postoperative BUN quartiles of cases (P = 0.003). After adjusting for the potential confounders, the odds ratio of recurrence was 3.069 (95%CI =1.488-6.330, p = 0.002) for the highest quartile of BUN compared with the lowest quartile. In multiple-adjusted spline regression, a high BUN level visually showed a significantly high OR value of recurrence risk.

Conclusions: Elevated BUN at post-operation is significantly associated with the recurrence of CSDH, and it is indicated that high levels of serum BUN after evacuation may serve as a risk factor for CSDH recurrence.
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http://dx.doi.org/10.1186/s12883-020-01985-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7653870PMC
November 2020

Safety and efficacy of aprepitant as mono and combination therapy for the prevention of emetogenic chemotherapy-induced nausea and vomiting: post-marketing surveillance in China.

Chin Clin Oncol 2020 Oct;9(5):68

Department of Medical Oncology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China; Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.

Background: The goal of this study was to evaluate aprepitant usage in the context of routine clinical practice with dose/regimens at the discretion of prescribers for chemotherapy-induced nausea and vomiting (CINV) treatments.

Methods: In this single arm, multicenter prospective study 1,000 patients with solid malignancies were enrolled across 21 centers in China. The primary endpoint was the rate of adverse events (AEs), including drug related AEs and serious AEs (SAEs). Secondary efficacy endpoints included the proportion of patients achieving complete response (CR; no vomiting, no nausea, and no use of rescue medication) within 120 h after highly emetogenic chemotherapy, the rates of no nausea and no vomiting, as well as quality of life (QoL). Multivariable logistic regression analysis was carried out to determine factors associated with the overall (0-120 h), acute (0-24 h) and delayed (25-120 h) CR.

Results: Of the 1,000 highly emetogenic chemotherapy treated patients enrolled in the study ≥1 AE, ≥1 drug related AE, ≥1 SAE and drug related SAE rates in 998 patients were 45.9%, 2.5%, 4.0% and 0.1%, respectively. Approximately half of the patients (455/990, 46.0%) received aprepitant as part of a 3-drug anti-CINV regimen consistent with prescribing guidelines. The overall CR (0 to 120 h) for anti-emetic drug use was 41.0%, with an acute CR of 66.0% and a delayed CR of 46.5%. The rates of no vomiting and no nausea after solely aprepitant anti-emetic therapy from 0 to 120 h were 70.9% and 43.0%, for dual anti-emetic therapy 86.9% and 64.6%, and for triple therapy 86.4% and 69.5%, respectively. Multivariate regression analysis revealed that triple anti-emetic therapy (P=0.038), male gender (P<0.001) and a history of chemotherapy (P=0.016) were significantly associated with the overall acute CR.

Conclusions: Especially as a combination treatment, aprepitant is safe and efficient for preventing CINV in patients receiving highly emetogenic chemotherapy.
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http://dx.doi.org/10.21037/cco-20-160DOI Listing
October 2020

Folic acid attenuates remodeling and dysfunction in the aging heart through the ER stress pathway.

Life Sci 2021 Jan 5;264:118718. Epub 2020 Nov 5.

Department of Cardiology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China. Electronic address:

Aims: Age-related structure changes and dysfunction of heart are likely to contribute heart failure in elderly people. Recent studies have shown that folic acid supplementation effectively delays age-related declines; nevertheless, the role and mechanism of folic acid in protection against cardiac aging remain unclear. The aim of the current study was to determine whether folic acid inhibits remodeling and dysfunction during the aging process and to elucidate its underlying mechanisms.

Main Methods: Male C57BL/6 mice aged 4 months (adult) and 14 months (aged) were fed a standard diet or a folic acid diet for 6 months. Echocardiograms and histological evaluations were used to detect left ventricle (LV) function, LV remodeling, cardiac fibrosis, apoptosis and oxidative stress. Senescence-associated β-galactosidase activity staining was used to detect cardiac senescence rate. Western blotting was employed to detect the levels of senescence and ER stress signaling.

Key Finding: LV hypertrophy was reduced and LV function was preserved in aged mice that consumed folic acid. LV remodeling, fibrosis, apoptosis and oxidative stress were also reduced in mice that consumed folic acid. Senescence-associated β-galactosidase activity staining revealed that folic acid attenuated cardiac senescence by down-regulating p53/p21/p16 levels. Protein assays of myocardial tissue revealed that the ER stress pathway is the important underlying mechanism during cardiac senescence. The involvement of these pathways was confirmed by doxorubicin-induced H9C2 cardiomyocyte senescence.

Significance: These findings suggest that folic acid prevents age-related cardiac remodeling and dysfunction and attenuates cellular senescence. ER stress responses may be the mechanisms involved in the protective effect of folic acid against cardiac aging.
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http://dx.doi.org/10.1016/j.lfs.2020.118718DOI Listing
January 2021

A Machine Learning Protocol for Predicting Protein Infrared Spectra.

J Am Chem Soc 2020 11 30;142(45):19071-19077. Epub 2020 Oct 30.

Hefei National Laboratory for Physical Sciences at the Microscale, CAS Center for Excellence in Nanoscience, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.

Infrared (IR) absorption provides important chemical fingerprints of biomolecules. Protein secondary structure determination from IR spectra is tedious since its theoretical interpretation requires repeated expensive quantum-mechanical calculations in a fluctuating environment. Herein we present a novel machine learning protocol that uses a few key structural descriptors to rapidly predict amide I IR spectra of various proteins and agrees well with experiment. Its transferability enabled us to distinguish protein secondary structures, probe atomic structure variations with temperature, and monitor protein folding. This approach offers a cost-effective tool to model the relationship between protein spectra and their biological/chemical properties.
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http://dx.doi.org/10.1021/jacs.0c06530DOI Listing
November 2020

Hypothesis: What is the Best We Can Do with Hydroxychloroquine for COVID-19?

Clin Epidemiol 2020 20;12:1139-1144. Epub 2020 Oct 20.

Campus Gasthuisberg, Group of Biomedical Sciences, KU, Leuven, Belgium.

There are widespread anecdotal reports of seemingly successful treatment among the early (three to seven days from symptoms) stage coronavirus disease 2019 (COVID-19) patients with the drug hydroxychloroquine (HCQ), and randomized placebo-controlled trials of HCQ in outpatient settings are underway. In this note, we (1) report observational evidence and present scientific reasoning as to why early treatment with HCQ may succeed while treatment later in the disease progression is likely to fail and (2) hypothesize a public health regime under which HCQ may be used to mitigate the impact of the current pandemic.
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http://dx.doi.org/10.2147/CLEP.S277889DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585824PMC
October 2020

Specific Gene Co-variation Acts Better Than Number of Concomitant Altered Genes in Predicting EGFR-TKI Efficacy in Non-small-cell Lung Cancer.

Clin Lung Cancer 2021 Jan 19;22(1):e98-e111. Epub 2020 Sep 19.

Department of Oncology, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China; Department of Oncology, Guangdong Provincial Hospital of Chinese Medicine, Guangzhou, China; Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome, Guangzhou, China. Electronic address:

Background: There occurs huge heterogeneity in clinical outcomes for patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) treated with EGFR tyrosine kinase inhibitors (EGFR-TKIs). The purpose of this study was to indicate genetic biomarkers predicting primary resistance of EGFR-TKIs in these patients.

Patients And Methods: Using a next-generation sequencing panel with 168 cancer-related genes, matched tumor biopsy and plasma samples before treatments from patients with NSCLC were analyzed. Patients taking EGFR-TKIs were followed-up with imaging examination. Correlation of co-alterative genes with progression-free survival (PFS) was analyzed.

Results: Of the 48 patients treated with EGFR-TKIs, 46 (95.83%) had at least 1 genetic co-variant beyond EGFR mutation. Multivariate analysis indicated that RB1, PIK3CA, and ERBB2 co-alterations, rather than number of co-alterative genes, were independently associated with poorer PFS. Grouping patients by specific gene status showed best likelihood ratio χ, Akaike information criterion, and Harrell concordance index. The median PFS for patients in group A (less genetic co-variations and wild specific genes), group B (more genetic co-variations and wild specific genes), group C (less genetic co-variations and altered specific genes), and group D (more genetic co-variations and altered specific genes) were 10.4, 9.13 (vs. group A; P = .3112), 6.33 (vs. group B; P = .0465), and 3.90 (vs. group C; P = .0309) months, respectively.

Conclusions: This study revealed a high concomitant genetic alteration rate in patients with EGFR-mutated NSCLC. Specific gene variants were more important than number of altered genes in predicting poor PFS, and may help select patients needing new treatment strategies.
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http://dx.doi.org/10.1016/j.cllc.2020.09.003DOI Listing
January 2021

Tim-3 Expression and MGMT Methylation Status Association With Survival in Glioblastoma.

Front Pharmacol 2020 15;11:584652. Epub 2020 Sep 15.

Department of Neurosurgery, The First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou, China.

Background: A profound understanding of the molecular landscape of glioblastoma multiforme (GBM) will make it possible to develop better and more intelligent therapies directed toward specific molecular targets and may one day yield better prognostic capabilities. Immune checkpoint molecules have inspired the emergence of immune checkpoint-targeting therapeutic strategies. However, the prognostic significance of the immune checkpoint molecule T cell immunoglobulin mucin-3 (Tim-3) on tumor-infiltrating immune cells (TIICs) and O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status has not yet been fully elucidated. We aimed to develop an MGMT promoter methylation status-associated immune prognostic signature for GBM.

Patients And Methods: A total of 84 patients with newly diagnosed GBM were included in this study. MGMT promoter methylation status was retrospectively analyzed, and the expression level of Tim-3 was investigated using immunohistochemistry (IHC). The correlation between Tim-3 expression combined with MGMT promoter methylation status and prognosis was explored.

Results: Tim-3 expression varied in GBM patients. Mesenchymal expression of Tim-3 in GBM tissues was present 73.81% (62/84) of patients, and these were subdivided into groups based on low 15.48% (13/84), moderate 7.14% (6/84), or strong expression 51.19% (43/84). Forty-eight patients had tumors that tested positive for MGMT promoter methylation, while the remaining 36 patients tested negative.

Conclusions: We profiled the immune status of MGMT promoter methylation in GBM and established a local immune signature for GBM that could independently identify patients with a favorable prognosis, indicating a relationship between prognosis and GBM immune signature. MGMT promoter methylation with lower Tim-3 expression was significantly associated with better survival.
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http://dx.doi.org/10.3389/fphar.2020.584652DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7522578PMC
September 2020

Alkalescent soda beverage caused the disappearance of gefitinib-induced rashes and decreased efficacy in a non-small-cell lung cancer patient treated with gefitinib: A case report.

Respir Med Case Rep 2020 16;31:101228. Epub 2020 Sep 16.

Department of Pulmonary and Critical Care Medicine, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 215006, China.

Oral anticancer drugs have the advantages of convenient and flexible administration, however, they also face some new problems related to their oral preparation. Herein we describe a case of advanced non-small-cell lung cancer patient treated with gefitinib who had long-term adverse reactions of rashes and diarrhea, and his rashes disappeared after taking alkaline soda, and then reappeared after stopping drinking it. Imaging progress was also observed. To our knowledge, this is the first report on the effect of alkaline food on gefitinib-induced rashes dynamic change. In this case, the rash acted as a signal of therapeutic efficacy. Clinicians and pharmacists should be aware of potential and common factors that affect drug efficacy and strive to achieve the best therapeutic results.
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http://dx.doi.org/10.1016/j.rmcr.2020.101228DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7516283PMC
September 2020

Recent Advances in the Use of Exosomes in Sjögren's Syndrome.

Front Immunol 2020 6;11:1509. Epub 2020 Aug 6.

Department of Rheumatology and Immunology, West China Hospital, Sichuan University, Chengdu, China.

Sjögren's syndrome (SS) is a chronic autoimmune disorder of the exocrine glands mediated by lymphocytic infiltrates damaging the body tissues and affecting the life quality of patients. Although traditional methods of diagnosis and treatment for SS are effective, in the time of personalized medicine, new biomarkers, and novel approaches are required for the detection and treatment of SS. Exosomes represent an emerging field in the discovery of biomarkers and the management of SS. Exosomes, a subtype of extracellular vesicles, are secreted by various cell types and can be found in most bodily fluids. Exosomes are packed with cytokines and other proteins, bioactive lipids, and nucleic acids (mRNA, circular RNA, non-coding RNA, tRNA, microRNA, genomic DNA, and ssDNA), and transport such cargo between cells. Evidence has indicated that exosomes may play roles in processes such as the modulation of the immune response and activation of inflammation. Moreover, due to features such as stability, low immunogenicity and toxicity, long half-life, and the capacity to penetrate the blood-brain barrier, exosomes have also emerged as therapeutic tools for SS. In this review, we summarize existing literature regarding the biogenesis, isolation, and function of exosomes, specifically focusing on exosomes as novel biomarkers and their potential therapeutic uses in SS.
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http://dx.doi.org/10.3389/fimmu.2020.01509DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7438915PMC
May 2021

Molecular basis for ligand activation of the human KCNQ2 channel.

Cell Res 2021 Jan 3;31(1):52-61. Epub 2020 Sep 3.

Department of Biophysics, and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China.

The voltage-gated potassium channel KCNQ2 is responsible for M-current in neurons and is an important drug target to treat epilepsy, pain and several other diseases related to neuronal hyper-excitability. A list of synthetic compounds have been developed to directly activate KCNQ2, yet our knowledge of their activation mechanism is limited, due to lack of high-resolution structures. Here, we report cryo-electron microscopy (cryo-EM) structures of the human KCNQ2 determined in apo state and in complex with two activators, ztz240 or retigabine, which activate KCNQ2 through different mechanisms. The activator-bound structures, along with electrophysiology analysis, reveal that ztz240 binds at the voltage-sensing domain and directly stabilizes it at the activated state, whereas retigabine binds at the pore domain and activates the channel by an allosteric modulation. By accurately defining ligand-binding sites, these KCNQ2 structures not only reveal different ligand recognition and activation mechanisms, but also provide a structural basis for drug optimization and design.
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http://dx.doi.org/10.1038/s41422-020-00410-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7852908PMC
January 2021

Confined Fe-Cu Clusters as Sub-Nanometer Reactors for Efficiently Regulating the Electrochemical Nitrogen Reduction Reaction.

Adv Mater 2020 Oct 2;32(40):e2004382. Epub 2020 Sep 2.

Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, School of Materials Science and Engineering, Tianjin University, Tianjin, 300350, China.

Electrochemical nitrogen reduction reaction (NRR) over nonprecious-metal and single-atom catalysts has received increasing attention as a sustainable strategy to synthesize ammonia. However, the atomic-scale regulation of such active sites for NRR catalysis remains challenging because of the large distance between them, which significantly weakens their cooperation. Herein, the utilization of regular surface cavities with unique microenvironment on graphitic carbon nitride as "subnano reactors" to precisely confine multiple Fe and Cu atoms for NRR electrocatalysis is reported. The synergy of Fe and Cu atoms in such confined subnano space provides significantly enhanced NRR performance, with nearly doubles ammonia yield and 54%-increased Faradic efficiency up to 34%, comparing with the single-metal counterparts. First principle simulation reveals this synergistic effect originates from the unique Fe-Cu coordination, which effectively modifies the N absorption, improves electron transfer, and offers extra redox couples for NRR. This work thus provides new strategies of manipulating catalysts active centers at the sub-nanometer scale.
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http://dx.doi.org/10.1002/adma.202004382DOI Listing
October 2020

Distribution pattern of invasion-related bio-markers in head Marjolin's ulcer.

Exp Ther Med 2020 Oct 23;20(4):3316-3323. Epub 2020 Jul 23.

Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang 325000, P.R. China.

Marjolin's ulcer (MU) is a rare and aggressive cutaneous malignancy that typically presented in an area of traumatized or chronically inflamed skin and particularly in burn scars. Among them, the MU in the scalp with extensive invasion of the skull is exceptional and severe. The principle of management for MU is to obtain an early diagnosis and perform prompt surgical interventions. The invasive capacity of MU may vary among different sites of the scalp, which may require different therapeutic strategies for surgical excision. However, no clear evidence has been provided to determine the invasion ability of MU at different regions of the lesion as a surgical guidance. In present study, a 41-year-old female with a 40-year history of scalp ulceration has been examined. After resection of the MU lesion, hematoxylin and eosin (H&E) staining was performed to confirm the pathology of the cutaneous malignancy after surgical excision. Furthermore, reverse transcription-quantitative PCR experiment was performed out to determine the expression levels of invasion-associated biomarkers at different sites of the scalp affected by MU. Pathological analysis with H&E staining indicated a differentiated squamous cell carcinoma with invasion of the skull. The invasion-associated biomarkers were highly expressed in the core region compared to the middle region as well as the edge of MU tissue. Taken together, the present study suggests that the expression pattern of invasion-associated biomarkers varies between different regions of the MU lesion. High expression levels in the core region of MU indicates that the resection of the center area may be critical for the successful surgical treatment of MU.
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http://dx.doi.org/10.3892/etm.2020.9034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7444365PMC
October 2020