Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully construct...Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24.展开更多
BACKGROUND Recent studies have indicated that an antibody against programmed cell death protein 1-ligand 1(PDCD1-LG1),a new marker of programmed cell death-ligand 1 expression,is promising for studying the mechanisms ...BACKGROUND Recent studies have indicated that an antibody against programmed cell death protein 1-ligand 1(PDCD1-LG1),a new marker of programmed cell death-ligand 1 expression,is promising for studying the mechanisms of breast cancer(BC)progression and resistance to chemotherapy.AIM To compare the features of PDCD1-LG1 expression in chemoresistant luminal A BC and BC with high Ki67 indices.METHODS This prospective single-center observational cohort study included 148 patients with newly diagnosed primary resectable BC.The tumor sections were stained with antibodies against PDCD1-LG1.The statistical calculations were performed using Statistica software version 12.0.P<0.05 was considered statistically significant.RESULTS Cytoplasmic PDCD1-LG1(cPDCD1-LG1)expression was detected in the nonneoplastic epithelium,tumor cells(TCs)and immune cells(ICs).A lack of cPDCD1-LG1 expression in≥20% of TCs and a PDCD1-LG1+IC score≥10%were associated with aggressive BC characteristics,including tumor G3,estrogen receptor-negative status,overexpression of human epidermal growth factor receptor 2(HER2+),luminal B HER2+BC,nonluminal HER2+BC and triplenegative BC.The lack of cPDCD1-LG1 expression in<20% of the TCs,in combination with a PDCD1-LG1+IC score<10% and G1,was characteristic of chemoresistant luminal A BC,whereas the lack of cPDCD1-LG1 expression in≥20% of the TCs,combined with a PDCD1-LG1+IC score≥10%,was a predictor of high BC sensitivity to chemotherapy.CONCLUSION These results indicate that both the lack of cPDCD1 LG1 in TCs and the PDCD1 LG1 IC score and their combination may be important for assessing BC prognosis and sensitivity to chemotherapy.展开更多
Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand...Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.展开更多
Selenolate ligands are expected to endow fluorescent gold nanoclusters(AuNCs)with better stability and more bioactivity than thiolate ligands,making them promising in the biological field.However,there are few studies...Selenolate ligands are expected to endow fluorescent gold nanoclusters(AuNCs)with better stability and more bioactivity than thiolate ligands,making them promising in the biological field.However,there are few studies on the synthesis of water-soluble selenolate-protected AuNCs,and the impact of selenolate ligands on the optical properties of AuNCs is still unclear.In this study,we synthesized selenolatecostabilized water-soluble,near-infrared fluorescent AuNCs with four different amounts of benzeneselenol(PhSeH),and systematically investigated the role of PhSeH on their optical properties.It is discovered that an appropriate PhSeH content is favorable for the fluorescence enhancement of AuNCs due to the ligand to metal charge transfer effect.Moreover,AuNCs co-stabilized by selenolate ligands exhibit better photostability and long-term stability compared with AuNCs stabilized by thiolate ligands,owing to the introduction of Au-Se bond on their surfaces.Further cellular experiments revealed that selenolate ligands can also affect the cellular uptake efficiency of AuNCs and their imaging property.These results provide important knowledges for further development of new,robust selenolate-stabilized metal NCs for biological application.展开更多
BACKGROUND The diagnosis of inflammatory bowel disease(IBD)involves clinical,endoscopic,and radiologic evaluation.Endoscopic procedures,particularly in pediatrics,require general anesthesia and carry potential risks.A...BACKGROUND The diagnosis of inflammatory bowel disease(IBD)involves clinical,endoscopic,and radiologic evaluation.Endoscopic procedures,particularly in pediatrics,require general anesthesia and carry potential risks.AIM To investigate whether serum biomarkers can differentiate between pediatric patients with and without IBD.Secondary objectives included identifying biomarkers that distinguish Crohn’s disease(CD)from ulcerative colitis(UC)and assessing their predictive value for progression to biologic therapy.METHODS Pediatric patients undergoing diagnostic colonoscopy at British Columbia Children’s Hospital between December 2017 and June 2022 were enrolled.Blood samples were collected at colonoscopy,and demographic clinical data,laboratory,and histopathologic evaluation were obtained.An exploratory screen of 50 biomarkers was undertaken in a subset of patients(54 IBD,41 controls)using LegendplexTM flow cytometry kits to identify candidates.A refined panel of 12 serum biomarkers was subsequently selected and a supervised learning model was developed to classify patients.RESULTS The study included 246 pediatric patients,who had a median age of 13.03 years and were 37.4%female(103 CD,52 UC,91 controls).In univariate analyses,C-X-C motif chemokine ligand 9(CXCL9)was the only biomarker significantly elevated in IBD vs controls(P<0.001).A multivariable model achieved an area under the receiver operating characteristic of 0.861 for distinguishing IBD from controls.Interleukin 8(IL-8)emerged as a key biomarker alongside CXCL9 and IL-22 in the model.The random forest model identified CXCL9 with the greatest diagnostic accuracy(area under the curve[AUC]=0.81),followed by IL8 and IL22(AUC=0.737 and 0.68,respectively).CXCL9 and IL-18 showed higher levels in CD(P=0.016),whereas CXCL1 levels predicted progression to biologic therapy within 1 year(P=0.039).However,the model did not effectively predict disease subclassification or progression to biologic therapy.CONCLUSION Serum biomarkers,particularly CXCL9,IL-8,and IL-22,can aid in the diagnosis of pediatric IBD.CXCL9 and IL18 were found to be significant predictors of CD,and CXCL1 differed between patients requiring biologic therapy vs those who did not.展开更多
BACKGROUND We previously demonstrated that the antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)is a promising new marker of programmed death-ligand 1(PD-L1)expression that correlates with both brea...BACKGROUND We previously demonstrated that the antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)is a promising new marker of programmed death-ligand 1(PD-L1)expression that correlates with both breast cancer(BC)clinicopathological characteristics and tumor sensitivity to chemotherapy.However,the concordance of PDCD1 LG1 expression scoring with immunohistochemical(IHC)tests approved for clinical use and with the polymerase chain reaction(PCR)method has not been previously studied.AIM To evaluate the concordance of methods for assessing PD-L1 expression,IHC tests with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and PCR.METHODS This prospective single-center observational cohort study included 148 patients with BC.PD-L1 expression in immune cells was assessed by the IHC method with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and by PCR.The concordance of PD-L1 scores between tests was assessed with positive percentage agreement(PPA)and negative percentage agreement(NPA).The strength of the agreement between the methods was calculated via the Cohen kappa index.P<0.05 was considered statistically significant.RESULTS Regardless of the method used to assess marker expression,PD-L1 expression was significantly more often detected in patients with negative estrogen receptor status,human epidermal growth factor receptor-2-positive(HER2+)status,luminal B HER+BC,nonluminal HER+BC and triple-negative BC.PPA and NPA were 38.3%and 70.4%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(SP142);26.3%and 63.3%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(PCR);and 36.5%and 74.4%,respectively,for PD-L1(SP142)and PD-L1(PCR).Cohen's kappa index for PD-L1(PDCD1 LG1)and PD-L1(SP142)was 0.385(95%CI:0.304–0.466),that for PD-L1(PDCD1 LG1)and PD-L1(PCR)was 0.207(95%CI:0.127–0.287),and that for PD-L1(SP142)and PD-L1(PCR)was 0.389(95%CI:0.309–0.469).CONCLUSION Thus,all three markers of PD-L1 expression are associated with the characteristics of aggressive BC,demonstrating moderate concordance between the tests.展开更多
(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under...(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.展开更多
Harnessing bacteria for superoxide production in bioremediation holds immense promise,yet its practical application is hindered by slow production rates and the relatively weak redox potential of superoxide.This study...Harnessing bacteria for superoxide production in bioremediation holds immense promise,yet its practical application is hindered by slow production rates and the relatively weak redox potential of superoxide.This study delves into a cost-effective approach to amplify superoxide production using an Arthrobacter strain,a prevalent soil bacterial genus.Our research reveals that introducing a carbon source along with specific iron-binding ligands,including deferoxamine(DFO),diethylenetriamine pentaacetate(DTPA),citrate,and oxalate,robustly augments microbial superoxide generation.Moreover,our findings suggest that these iron-binding ligands play a pivotal role in converting superoxide into hydroxyl radicals by modulating the electron transfer rate between Fe(Ⅲ)/Fe(Ⅱ)and superoxide.Remarkably,among the tested ligands,only DTPA emerges as a potent promoter of this conversion process when complexed with Fe(Ⅲ).We identify an optimal Fe(Ⅲ)to DTPA ratio of approximately 1:1 for enhancing hydroxyl radical production within the Arthrobacter culture.This research underscores the efficacy of simultaneously introducing carbon sources and DTPA in facilitating superoxide production and its subsequent conversion to hydroxyl radicals,significantly elevating bioremediation performance.Furthermore,our study reveals that DTPA augments superoxide production in cultures of diverse soils,with various soil microorganisms beyond Arthrobacter identified as contributors to superoxide generation.This emphasizes the universal applicability of DTPA across multiple bacterial genera.In conclusion,our study introduces a promising methodology for enhancing microbial superoxide production and its conversion into hydroxyl radicals.These findings hold substantial implications for the deployment of microbial reactive oxygen species in bioremediation,offering innovative solutions for addressing environmental contamination challenges.展开更多
Traditional p-type colloidal quantum dot(CQD)hole transport layers(HTLs)used in CQD solar cells(CQDSCs)are commonly based on organic ligands exchange and the layer-by-layer(LbL)technique.Nonetheless,the ligand detachm...Traditional p-type colloidal quantum dot(CQD)hole transport layers(HTLs)used in CQD solar cells(CQDSCs)are commonly based on organic ligands exchange and the layer-by-layer(LbL)technique.Nonetheless,the ligand detachment and complex fabrication process introduce surface defects,compromising device stability and efficiency.In this work,we propose a solution-phase ligand exchange(SPLE)method utilizing inorganic ligands to develop stable p-type lead sulfide(PbS)CQD inks for the first time.Various amounts of tin(Ⅱ)iodide(SnI_(2))were mixed with lead halide(PbX_(2);X=I,Br)in the ligand solution.By precisely controlling the SnI_(2)concentration,we regulate the transition of PbS QDs from n-type to p-type.PbS CQDSCs were fabricated using two different HTL approaches:one with 1,2-ethanedithiol(EDT)-passivated QDs via the LbL method(control)and another with inorganic ligand-passivated QD ink(target).The target devices achieved a higher power conversion efficiency(PCE)of 10.93%,compared to 9.83%for the control devices.This improvement is attributed to reduced interfacial defects and enhanced carrier mobility.The proposed technique offers an efficient pathway for producing stable p-type PbS CQD inks using inorganic ligands,paving the way for high-performance and flexible CQD-based optoelectronic devices.展开更多
Five cadmium naphthalene-diphosphonates,formulated as[Cd_(1.5)(1,4-ndpaH_(2))2(4,4'-bpyH)(4,4'-bpy)0.5(H_(2)O)_(2)]2(1),[Cd(1,4-ndpaH_(2))(1,4-bib)0.5(H_(2)O)](2),[Cd(1,4-ndpaH3)2(1,2-dpe)(H_(2)O)]·(1,2-d...Five cadmium naphthalene-diphosphonates,formulated as[Cd_(1.5)(1,4-ndpaH_(2))2(4,4'-bpyH)(4,4'-bpy)0.5(H_(2)O)_(2)]2(1),[Cd(1,4-ndpaH_(2))(1,4-bib)0.5(H_(2)O)](2),[Cd(1,4-ndpaH3)2(1,2-dpe)(H_(2)O)]·(1,2-dpe)·7H_(2)O(3),(1,2-bixH)[Cd3(1,4-ndpaH)(1,4-ndpaH_(2))2(H_(2)O)_(2)](4),and[Cd(1,4-ndpaH_(2))(H_(2)O)]·H_(2)O(5),have been synthesized from the selfassembly reactions of 1,4-naphthalenediphosphonic acid(1,4-ndpaH4)with Cd(NO3)2·4H_(2)O by introducing auxiliary ligands with variation of rigidity,such as 4,4'-bipyridine(4,4'-bpy),1,4-bis(1-imidazolyl)benzene(1,4-bib),1,2-di(4-pyridyl)ethylene(1,2-dpe),1,3-di(4-pyridyl)propane(1,3-dpp),and bis(imidazol-1-ylmethyl)benzene(1,2-bix),respectively.Structure resolution by single-crystal X-ray diffraction reveals that compound 1 possesses a layered framework,in which the{Cd3(PO2)2}trimers made up of corner-sharing two{CdO4N2}and one{CdO6}octahedra are connected by phosphonate groups,forming a ribbon,which are cross-linked by 4,4'-bipy ligands,forming a 2D layer.Compound 2 shows a 3D open-framework structure,where chains of corner-sharing{CdO4N}trigonal bipyramids and{PO3C}tetrahedra are cross-linked by 1,4-bib and/or phosphonate groups.A 1D ladder-like chain structure is found in compound 3,where the ladder-like chains made up of corner-sharing{CdO5N}octahedra and{PO3C}tetra hedra are connected by 1,4-ndpaH_(2)^(2-).Both compounds 4 and 5 obtained by the introduction of flexible ligands during the synthesis show a 2D layered structure,which is formed by ligand crosslinking double metal chains.Interestingly,In 4,flexible 1,2-bix was singly protonated,as vip molecules,filled between layer and layer,while flexible ligand 1,3-dpp is absent in 5.Photophysical measurements indicate that compounds 1-5 show ligand-centered emissions.展开更多
To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(...To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.展开更多
The hydroformylation of olefins,known as the"oxo reaction",involves the use of syngas(CO/H_(2))to produce aldehyde with an additional carbon atom.However,side reactions such as the isomerization or hydrogena...The hydroformylation of olefins,known as the"oxo reaction",involves the use of syngas(CO/H_(2))to produce aldehyde with an additional carbon atom.However,side reactions such as the isomerization or hydrogenation of olefins often result in unexpected products and other by-products.Recent efforts in developing efficient ligands represent the most effective approach to addressing these challenges.In this study,we described a Bis-OPNN phosphorus ligand facilitated Rh-catalyzed hydroformylation with a high degree of linear selectivity across various olefins.Under mild conditions,a broad range of olefins were efficiently converted into linear aldehydes with high yields and excellent regioselectivity.The protocol also showed impressive functional group tolerance and was successfully applied to modify drugs and natural products,including the total synthesis of(±)-crispine A.Preliminary mechanistic studies revealed that this Bis-OPNN phosphorus ligand anchoring the rhodium catalyst is crucial for controlling the linear selectivity.展开更多
Regulating the photo-response region of iron metal-organic frameworks(Fe-MOFs)is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process.This study developed a...Regulating the photo-response region of iron metal-organic frameworks(Fe-MOFs)is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process.This study developed a novel pyrazine-based Fe-MOFs(MIL-101(Fe)-Pz)by substituting the 1,4-dicarboxybenzene acid ligands in typical MIL-101(Fe)with 2,5-pyrazinedicarboxylic acid(PzDC),in which sodium acetate was used as coordinative modulator to control the crystal size(2–3μm).The incorporation of Fe-pyridine N coordination structures originated from PzDC ligands gave MIL-101(Fe)-Pz narrowed band gap(1.45 eV)than MIL-101(Fe)(2.54 eV)resulting in improved visible-light adsorption capacity(λ>420 nm),and also increased the proportion of Fe(Ⅱ)in the Fe-clusters.Thus MIL-101(Fe)-Pz exhibited a synergistic enhanced photo-Fenton-like catalytic performance under visible-light irradiation.The MIL-101(Fe)-Pz/H_(2)O_(2)/Vis system could degrade 99%of sulfamethoxazolewithin 30min,whichwas 10-fold faster than that of the pristine MIL-101(Fe),it also effectively removed other organic micropollutants with high durability and stability.Mechanistic analysis revealed that the PzDC ligands substitution decreased the band gap of MIL-101(Fe),giving MIL-101(Fe)-Pz appropriate band structure(-0.40∼1.05 V vs.NHE)which can cover several light-driven process for the generation of reactive oxygen species,including Fe(Ⅲ)reduction and H_(2)O_(2) activation for accelerating•OH generation,as well as oxygen reduction reaction for generating H_(2)O_(2),O_(2)^(•−) and ^(1)O_(2).This study highlights the role of pyridine-N containing ligands in regulating the band structure of Fe-MOFs,providing valuable guidance for the design of Fe-MOFs photocatalysts.展开更多
A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assig...A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.展开更多
Crystalline metal cluster-based organic-inorganic hybrid materials have emerged as a significant frontier in materials chemistry due to their unique structural designability and tunable properties.The bifunctional lig...Crystalline metal cluster-based organic-inorganic hybrid materials have emerged as a significant frontier in materials chemistry due to their unique structural designability and tunable properties.The bifunctional ligand 2-(hydroxymethyl)-2-(4-pyridyl)-1,3-propanediol(H3L),featuring both hard hydroxyl donors on one side and a soft pyridyl group on the other side,enables selective metal coordination via hard-soft acid-base(HSAB)theory and directs hierarchical metal cluster assembly.This review systematically summarizes the recent advances on metal cluster-based materials coordinated by H_(3)L,including their syntheses,crystal structures,and related physicochemical properties.展开更多
Formamidinium lead bromide(FAPbBr_(3))perovskite nanocrystals(NCs)are promising for display and lighting due to their ultra-pure green emission.However,the thermal quenching will exacerbate their performance degradati...Formamidinium lead bromide(FAPbBr_(3))perovskite nanocrystals(NCs)are promising for display and lighting due to their ultra-pure green emission.However,the thermal quenching will exacerbate their performance degradation in practical applications,which is a common issue for halide perovskites.Here,we reported the heat-resistant FAPbBr_(3)NCs prepared by a ligand-engineered room-temperature synthesis strategy.An aromatic amine,specificallyβ-phenylethylamine(PEA)or 3-fluorophenylethylamine(3-F-PEA),was incoporated as the short-chain ligand to expedite the crystallization rate and control the size distribution of FAPbBr_(3)NCs.Employing this ligand engineering approach,we synthesized high quality FAPbBr_(3)NCs with uniform grain size and reduced long-chain alkyl ligands,resulting in substantially suppressed thermal quenching and enhanced carrier transportation in the perovskite NCs films.Most notably,more than 90%of the room temperature PL intensity in the 3-F-PEA modified FAPbBr_(3)NCs film was preserved at 380 K.Consequently,we fabricated ultra-pure green EL devices with a room temperature external quantum efficiency(EQE)as high as 21.9%at the luminance of above 1,000 cd m^(-2),and demonstrated less than 10%loss in EQE at 343 K.This study introduces a novel room temperature method to synthesize efficient FAPbBr_(3)NCs with exceptional thermal stability,paving the way for advanced optoelectronic device applications.展开更多
Pt-rare-earth(PtRE)alloys are considered to be highly promising catalysts for oxygen reduction reaction(ORR)in acidic electrolytes.However,the wet-chemical synthesis of PtRE nanoalloys still faces significant challeng...Pt-rare-earth(PtRE)alloys are considered to be highly promising catalysts for oxygen reduction reaction(ORR)in acidic electrolytes.However,the wet-chemical synthesis of PtRE nanoalloys still faces significant challenges.The precise reaction mechanism for ORR of these catalysts is still unclear on significant aspects involving the rate-determining step and the nature of the ligand effect.Herein,we report a class of solvothermal synthesis of PtRE(RE is Dy or La)nanoalloys.Such PtRE nanoalloys here are active and stable in acidic media,with both high mass activities enhanced by 2-5 times relative to commercial Pt/C catalyst and high stabilities indicative of the little activity decay and negligible structure change after 10,000 cycles.Density functional theory calculations firmly confirm that the ligand effect of RE elements accelerates an O-O bond scission and steers the rate-determining steps from OH^(*)+H^(+)+e-→H_(2)O(on pure Pt surface)to HOOH^(*)+H^(+)+e-→OH^(*)+H_(2)O(on the PtRE nanoalloy surface)for the fast reaction kinetics,which could be fine-tuned by regulating the RE electronic structures and consequently endows the maximal rate of ORR catalysis with PtDy alloy catalysts.展开更多
BACKGROUND In recent years,emerging clinical research has prioritized assessment of combined therapeutic efficacy and safety parameters when programmed death 1 or its ligand(PD-1/L1)inhibitors are incorporated into fi...BACKGROUND In recent years,emerging clinical research has prioritized assessment of combined therapeutic efficacy and safety parameters when programmed death 1 or its ligand(PD-1/L1)inhibitors are incorporated into first-line standard-of-care(SOC)therapy for metastatic colorectal cancer(mCRC).However,data obtained from these trials demonstrated conflicting evidence concerning survival benefits and clinical outcomes.AIM To evaluate the therapeutic impact and safety parameters of combining PD-1/L1 inhibitors with SOC protocols as first-line treatment for mCRC.METHODS Four biomedical databases(PubMed,Embase,Cochrane Library,Web of Science)were systematically interrogated to identify eligible studies published up to October 12,2024.The analysis focused on evaluating the primary outcome of overall survival(OS)in the mCRC population with secondary outcomes of progression-free survival(PFS),overall response rate(ORR),and incidence rate of grade≥3 adverse events.Additionally,we performed exploratory analyses in the microsatellite stable/mismatch repair-proficient(MSS/pMMR)subpopulation,based on a subset of the included studies.Subgroup analyses according to PD-1/L1 inhibitor use were conducted in both the overall population and the MSS/pMMR subgroup.RESULTS This pooled analysis incorporated six randomized controlled trials involving 675 patients with mCRC receiving first-line therapy.The combination of PD-1/L1 inhibitors with SOC regimens demonstrated a significant PFS advantage over SOC monotherapy in intention-to-treat populations[hazard ratio(HR)=0.8,95%confidence interval(CI):0.65-0.98,P=0.033].Nevertheless,the MSS/pMMR subgroup showed no PFS benefit(HR=0.83,95%CI:0.67-1.03,P=0.091),and no cohort exhibited OS improvement(intention-to-treat:HR=0.84,95%CI:0.66-1.05,P=0.124;MSS/pMMR:HR=0.79,95%CI:0.60-1.03,P=0.083).Comparable outcomes were observed for ORR(risk ratio=1.03,95%CI:0.90-1.17,P=0.711)and incidence rate of grade≥3 adverse events(risk ratio=1.12,95%CI:0.93-1.36,P=0.245)between treatment arms.CONCLUSION The findings indicated that integrating PD-1/L1 blocking agents with SOC regimens for mCRC as first-line treatment failed to demonstrate significant improvements in ORR.Existing clinical data remain inadequate to establish OS advantages,particularly in patients with MSS/pMMR,despite exhibiting manageable toxicity profiles.Subsequent confirmation through rigorously designed phase III clinical trials remains essential to verify these therapeutic outcomes.展开更多
The atomic-level exploration of structure-property correlations poses significant challenges in establishing precise design principles for electrocatalysts targeting efficient CO_(2)conversion.This study demonstrates ...The atomic-level exploration of structure-property correlations poses significant challenges in establishing precise design principles for electrocatalysts targeting efficient CO_(2)conversion.This study demonstrates how controlled exposure of metal sites governs CO_(2)electroreduction performance through two octanuclear bismuth-oxo clusters with distinct architectures.The Bi_(8)-DMF cluster,constructed using tert–butylthiacalix[4]arene(TC4A)as the sole ligand,features two surface-exposed Bi active sites,while the dual-ligand Bi_(8)-Fc(with TC4A/ferrocene carboxylate)forms a fully encapsulated structure.Electrocatalytic tests reveal Bi_(8)-DMF achieves exceptional formate selectivity(>90%Faradaic efficiency)across a broad potential window(-0.9 V to-1.6 V vs.RHE)with 20 h stability,outperforming Bi_(8)-Fc(60%efficiency at-1.5 V).Theoretical calculations attribute Bi_(8)-DMF's superiority to exposed Bi sites that stabilize the critical*OCHO intermediate via optimized orbital interactions.This work provides crucial guidance for polynuclear catalyst design:moderate exposure of metal active sites significantly enhances CO_(2)reduction performance.展开更多
Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge ...Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge transport layers often lead to reduced power conversion efficiency(PCE).Surface treatment is an effective strategy but the passivating ligands usually bind with a single active site.The resulted dense packing of resistive passivators perpendicular to the surface is detrimental to charge transport.Here,we present a passivator that can bind to two neighboring lead(Ⅱ)ion(Pb^(2+))defect sites simultaneously with an aligned parallel mode to the perovskite surface,effectively suppressing the surface trap density and preventing the aggregation.The target device fulfills a PCE of 25.1%and maintains over 85% of the initial efficiency after 800 h of exposure to a relative humidity(RH)of 65%±5%.展开更多
文摘Under hydrothermal and solvothermal conditions,two novel cobalt-based complexes,{[Co_(2)(CIA)(OH)(1,4-dtb)]·3.2H_(2)O}n(HU23)and{[Co_(2)(CIA)(OH)(1,4-dib)]·3.5H2O·DMF}n(HU24),were successfully constructed by coordinatively assembling the semi-rigid multidentate ligand 5-(1-carboxyethoxy)isophthalic acid(H₃CIA)with the Nheterocyclic ligands 1,4-di(4H-1,2,4-triazol-4-yl)benzene(1,4-dtb)and 1,4-di(1H-imidazol-1-yl)benzene(1,4-dib),respectively,around Co^(2+)ions.Single-crystal X-ray diffraction analysis revealed that in both complexes HU23 and HU24,the CIA^(3-)anions adopt aκ^(7)-coordination mode,bridging six Co^(2+)ions via their five carboxylate oxygen atoms and one ether oxygen atom.This linkage forms tetranuclear[Co4(μ3-OH)2]^(6+)units.These Co-oxo cluster units were interconnected by CIA^(3-)anions to assemble into 2D kgd-type structures featuring a 3,6-connected topology.The 2D layers were further connected by 1,4-dtb and 1,4-dib,resulting in 3D pillar-layered frameworks for HU23 and HU24.Notably,despite the similar configurations of 1,4-dtb and 1,4-dib,differences in their coordination spatial orientations lead to topological divergence in the 3D frameworks of HU23 and HU24.Topological analysis indicates that the frameworks of HU23 and HU24 can be simplified into a 3,10-connected net(point symbol:(4^(10).6^(3).8^(2))(4^(3))_(2))and a 3,8-connected tfz-d net(point symbol:(4^(3))_(2)((4^(6).6^(18).8^(4)))),respectively.This structural differentiation confirms the precise regulatory role of ligands on the topology of metal-organic frameworks.Moreover,the ultraviolet-visible absorption spectra confirmed that HU23 and HU24 have strong absorption capabilities for ultraviolet and visible light.According to the Kubelka-Munk method,their bandwidths were 2.15 and 2.08 eV,respectively,which are consistent with those of typical semiconductor materials.Variable-temperature magnetic susceptibility measurements(2-300 K)revealed significant antiferromagnetic coupling in both complexes,with their effective magnetic moments decreasing markedly as the temperature lowered.CCDC:2457554,HU23;2457553,HU24.
基金Supported by the Russian Science Foundation,No.23-25-00183.
文摘BACKGROUND Recent studies have indicated that an antibody against programmed cell death protein 1-ligand 1(PDCD1-LG1),a new marker of programmed cell death-ligand 1 expression,is promising for studying the mechanisms of breast cancer(BC)progression and resistance to chemotherapy.AIM To compare the features of PDCD1-LG1 expression in chemoresistant luminal A BC and BC with high Ki67 indices.METHODS This prospective single-center observational cohort study included 148 patients with newly diagnosed primary resectable BC.The tumor sections were stained with antibodies against PDCD1-LG1.The statistical calculations were performed using Statistica software version 12.0.P<0.05 was considered statistically significant.RESULTS Cytoplasmic PDCD1-LG1(cPDCD1-LG1)expression was detected in the nonneoplastic epithelium,tumor cells(TCs)and immune cells(ICs).A lack of cPDCD1-LG1 expression in≥20% of TCs and a PDCD1-LG1+IC score≥10%were associated with aggressive BC characteristics,including tumor G3,estrogen receptor-negative status,overexpression of human epidermal growth factor receptor 2(HER2+),luminal B HER2+BC,nonluminal HER2+BC and triplenegative BC.The lack of cPDCD1-LG1 expression in<20% of the TCs,in combination with a PDCD1-LG1+IC score<10% and G1,was characteristic of chemoresistant luminal A BC,whereas the lack of cPDCD1-LG1 expression in≥20% of the TCs,combined with a PDCD1-LG1+IC score≥10%,was a predictor of high BC sensitivity to chemotherapy.CONCLUSION These results indicate that both the lack of cPDCD1 LG1 in TCs and the PDCD1 LG1 IC score and their combination may be important for assessing BC prognosis and sensitivity to chemotherapy.
基金supported by the National Natural Science Foundation of China(Key Program),No.11932013the National Natural Science Foundation of China(General Program),No.82272255+2 种基金Armed Police Force High-Level Science and Technology Personnel ProjectThe Armed Police Force Focuses on Supporting Scientific and Technological Innovation TeamsKey Project of Tianjin Science and Technology Plan,No.20JCZDJC00570(all to XC)。
文摘Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory damage.The expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after injury.Recent studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for treatment.This review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord injury.Additionally,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted drugs.Nevertheless,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis.This review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.
基金support from the National Natural Science Foundation of China(No.22274131)Shaanxi Fundamental Science Research Project for Chemistry&Biology(No.22JHQ071)。
文摘Selenolate ligands are expected to endow fluorescent gold nanoclusters(AuNCs)with better stability and more bioactivity than thiolate ligands,making them promising in the biological field.However,there are few studies on the synthesis of water-soluble selenolate-protected AuNCs,and the impact of selenolate ligands on the optical properties of AuNCs is still unclear.In this study,we synthesized selenolatecostabilized water-soluble,near-infrared fluorescent AuNCs with four different amounts of benzeneselenol(PhSeH),and systematically investigated the role of PhSeH on their optical properties.It is discovered that an appropriate PhSeH content is favorable for the fluorescence enhancement of AuNCs due to the ligand to metal charge transfer effect.Moreover,AuNCs co-stabilized by selenolate ligands exhibit better photostability and long-term stability compared with AuNCs stabilized by thiolate ligands,owing to the introduction of Au-Se bond on their surfaces.Further cellular experiments revealed that selenolate ligands can also affect the cellular uptake efficiency of AuNCs and their imaging property.These results provide important knowledges for further development of new,robust selenolate-stabilized metal NCs for biological application.
基金Supported by the Lutsky Family Foundation and AdMare Bioinnovations(previously known as the Genome BC CDRD Development Fund).
文摘BACKGROUND The diagnosis of inflammatory bowel disease(IBD)involves clinical,endoscopic,and radiologic evaluation.Endoscopic procedures,particularly in pediatrics,require general anesthesia and carry potential risks.AIM To investigate whether serum biomarkers can differentiate between pediatric patients with and without IBD.Secondary objectives included identifying biomarkers that distinguish Crohn’s disease(CD)from ulcerative colitis(UC)and assessing their predictive value for progression to biologic therapy.METHODS Pediatric patients undergoing diagnostic colonoscopy at British Columbia Children’s Hospital between December 2017 and June 2022 were enrolled.Blood samples were collected at colonoscopy,and demographic clinical data,laboratory,and histopathologic evaluation were obtained.An exploratory screen of 50 biomarkers was undertaken in a subset of patients(54 IBD,41 controls)using LegendplexTM flow cytometry kits to identify candidates.A refined panel of 12 serum biomarkers was subsequently selected and a supervised learning model was developed to classify patients.RESULTS The study included 246 pediatric patients,who had a median age of 13.03 years and were 37.4%female(103 CD,52 UC,91 controls).In univariate analyses,C-X-C motif chemokine ligand 9(CXCL9)was the only biomarker significantly elevated in IBD vs controls(P<0.001).A multivariable model achieved an area under the receiver operating characteristic of 0.861 for distinguishing IBD from controls.Interleukin 8(IL-8)emerged as a key biomarker alongside CXCL9 and IL-22 in the model.The random forest model identified CXCL9 with the greatest diagnostic accuracy(area under the curve[AUC]=0.81),followed by IL8 and IL22(AUC=0.737 and 0.68,respectively).CXCL9 and IL-18 showed higher levels in CD(P=0.016),whereas CXCL1 levels predicted progression to biologic therapy within 1 year(P=0.039).However,the model did not effectively predict disease subclassification or progression to biologic therapy.CONCLUSION Serum biomarkers,particularly CXCL9,IL-8,and IL-22,can aid in the diagnosis of pediatric IBD.CXCL9 and IL18 were found to be significant predictors of CD,and CXCL1 differed between patients requiring biologic therapy vs those who did not.
基金Supported by Russian Science Foundation,No.23-25-00183.
文摘BACKGROUND We previously demonstrated that the antibody against programmed cell death protein 1 ligand 1(PDCD1 LG1)is a promising new marker of programmed death-ligand 1(PD-L1)expression that correlates with both breast cancer(BC)clinicopathological characteristics and tumor sensitivity to chemotherapy.However,the concordance of PDCD1 LG1 expression scoring with immunohistochemical(IHC)tests approved for clinical use and with the polymerase chain reaction(PCR)method has not been previously studied.AIM To evaluate the concordance of methods for assessing PD-L1 expression,IHC tests with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and PCR.METHODS This prospective single-center observational cohort study included 148 patients with BC.PD-L1 expression in immune cells was assessed by the IHC method with anti-PD-L1(PDCD1 LG1)and anti-PD-L1(SP142)antibodies and by PCR.The concordance of PD-L1 scores between tests was assessed with positive percentage agreement(PPA)and negative percentage agreement(NPA).The strength of the agreement between the methods was calculated via the Cohen kappa index.P<0.05 was considered statistically significant.RESULTS Regardless of the method used to assess marker expression,PD-L1 expression was significantly more often detected in patients with negative estrogen receptor status,human epidermal growth factor receptor-2-positive(HER2+)status,luminal B HER+BC,nonluminal HER+BC and triple-negative BC.PPA and NPA were 38.3%and 70.4%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(SP142);26.3%and 63.3%,respectively,for PD-L1(PDCD1 LG1)and PD-L1(PCR);and 36.5%and 74.4%,respectively,for PD-L1(SP142)and PD-L1(PCR).Cohen's kappa index for PD-L1(PDCD1 LG1)and PD-L1(SP142)was 0.385(95%CI:0.304–0.466),that for PD-L1(PDCD1 LG1)and PD-L1(PCR)was 0.207(95%CI:0.127–0.287),and that for PD-L1(SP142)and PD-L1(PCR)was 0.389(95%CI:0.309–0.469).CONCLUSION Thus,all three markers of PD-L1 expression are associated with the characteristics of aggressive BC,demonstrating moderate concordance between the tests.
文摘(2E,6E)-4-methyl-2,6-bis(pyridin-3-ylmethylene)cyclohexan-1-one(L_(1))and 4-methyl-2,6-bis[(E)-4-(pyridin-4-yl)benzylidene]cyclohexan-1-one(L_(2))were synthesized and combined with isophthalic acid(H_(2)IP),then under solvothermal conditions,to react with transition metals achieving four novel metal-organic frameworks(MOFs):[Zn(IP)(L_(1))]_(n)(1),{[Cd(IP)(L_(1))]·H_(2)O}_(n)(2),{[Co(IP)(L_(1))]·H_(2)O}_(n)(3),and[Zn(IP)(L_(2))(H_(2)O)]_(n)(4).MOFs 1-4 have been characterized by single-crystal X-ray diffraction,powder X-ray diffraction,thermogravimetry,and elemental analysis.Single-crystal X-ray diffraction shows that MOF 1 crystallizes in the monoclinic crystal system with space group P2_(1)/n,and MOFs 2-4 belong to the triclinic system with the P1 space group.1-3 are 2D sheet structures,2 and 3 have similar structural characters,whereas 4 is a 1D chain structure.Furthermore,1-3 exhibited certain photocatalytic capability in the degradation of rhodamine B(Rh B)and pararosaniline hydrochloride(PH).4could be used as a heterogeneous catalyst for the Knoevenagel reaction starting with benzaldehyde derivative and malononitrile.4 could promote the reaction to achieve corresponding products in moderate yields within 3 h.Moreover,the catalyst exhibited recyclability for up to three cycles without significantly dropping its activity.A mechanism for MOF 4 catalyzed Knoevenagel condensation reaction of aromatic aldehyde and malononitrile has been initially proposed.CCDC:2356488,1;2356497,2;2356499,3;2356498,4.
基金supported by the National Natural Science Foundation of China(Nos.52170156,52250056,and 52293443)the Shenzhen Science and Technology Program(No.KQTD20190929172630447).
文摘Harnessing bacteria for superoxide production in bioremediation holds immense promise,yet its practical application is hindered by slow production rates and the relatively weak redox potential of superoxide.This study delves into a cost-effective approach to amplify superoxide production using an Arthrobacter strain,a prevalent soil bacterial genus.Our research reveals that introducing a carbon source along with specific iron-binding ligands,including deferoxamine(DFO),diethylenetriamine pentaacetate(DTPA),citrate,and oxalate,robustly augments microbial superoxide generation.Moreover,our findings suggest that these iron-binding ligands play a pivotal role in converting superoxide into hydroxyl radicals by modulating the electron transfer rate between Fe(Ⅲ)/Fe(Ⅱ)and superoxide.Remarkably,among the tested ligands,only DTPA emerges as a potent promoter of this conversion process when complexed with Fe(Ⅲ).We identify an optimal Fe(Ⅲ)to DTPA ratio of approximately 1:1 for enhancing hydroxyl radical production within the Arthrobacter culture.This research underscores the efficacy of simultaneously introducing carbon sources and DTPA in facilitating superoxide production and its subsequent conversion to hydroxyl radicals,significantly elevating bioremediation performance.Furthermore,our study reveals that DTPA augments superoxide production in cultures of diverse soils,with various soil microorganisms beyond Arthrobacter identified as contributors to superoxide generation.This emphasizes the universal applicability of DTPA across multiple bacterial genera.In conclusion,our study introduces a promising methodology for enhancing microbial superoxide production and its conversion into hydroxyl radicals.These findings hold substantial implications for the deployment of microbial reactive oxygen species in bioremediation,offering innovative solutions for addressing environmental contamination challenges.
基金supported by MEXT KAKENHI Grant(24K01295,26286013).
文摘Traditional p-type colloidal quantum dot(CQD)hole transport layers(HTLs)used in CQD solar cells(CQDSCs)are commonly based on organic ligands exchange and the layer-by-layer(LbL)technique.Nonetheless,the ligand detachment and complex fabrication process introduce surface defects,compromising device stability and efficiency.In this work,we propose a solution-phase ligand exchange(SPLE)method utilizing inorganic ligands to develop stable p-type lead sulfide(PbS)CQD inks for the first time.Various amounts of tin(Ⅱ)iodide(SnI_(2))were mixed with lead halide(PbX_(2);X=I,Br)in the ligand solution.By precisely controlling the SnI_(2)concentration,we regulate the transition of PbS QDs from n-type to p-type.PbS CQDSCs were fabricated using two different HTL approaches:one with 1,2-ethanedithiol(EDT)-passivated QDs via the LbL method(control)and another with inorganic ligand-passivated QD ink(target).The target devices achieved a higher power conversion efficiency(PCE)of 10.93%,compared to 9.83%for the control devices.This improvement is attributed to reduced interfacial defects and enhanced carrier mobility.The proposed technique offers an efficient pathway for producing stable p-type PbS CQD inks using inorganic ligands,paving the way for high-performance and flexible CQD-based optoelectronic devices.
文摘Five cadmium naphthalene-diphosphonates,formulated as[Cd_(1.5)(1,4-ndpaH_(2))2(4,4'-bpyH)(4,4'-bpy)0.5(H_(2)O)_(2)]2(1),[Cd(1,4-ndpaH_(2))(1,4-bib)0.5(H_(2)O)](2),[Cd(1,4-ndpaH3)2(1,2-dpe)(H_(2)O)]·(1,2-dpe)·7H_(2)O(3),(1,2-bixH)[Cd3(1,4-ndpaH)(1,4-ndpaH_(2))2(H_(2)O)_(2)](4),and[Cd(1,4-ndpaH_(2))(H_(2)O)]·H_(2)O(5),have been synthesized from the selfassembly reactions of 1,4-naphthalenediphosphonic acid(1,4-ndpaH4)with Cd(NO3)2·4H_(2)O by introducing auxiliary ligands with variation of rigidity,such as 4,4'-bipyridine(4,4'-bpy),1,4-bis(1-imidazolyl)benzene(1,4-bib),1,2-di(4-pyridyl)ethylene(1,2-dpe),1,3-di(4-pyridyl)propane(1,3-dpp),and bis(imidazol-1-ylmethyl)benzene(1,2-bix),respectively.Structure resolution by single-crystal X-ray diffraction reveals that compound 1 possesses a layered framework,in which the{Cd3(PO2)2}trimers made up of corner-sharing two{CdO4N2}and one{CdO6}octahedra are connected by phosphonate groups,forming a ribbon,which are cross-linked by 4,4'-bipy ligands,forming a 2D layer.Compound 2 shows a 3D open-framework structure,where chains of corner-sharing{CdO4N}trigonal bipyramids and{PO3C}tetrahedra are cross-linked by 1,4-bib and/or phosphonate groups.A 1D ladder-like chain structure is found in compound 3,where the ladder-like chains made up of corner-sharing{CdO5N}octahedra and{PO3C}tetra hedra are connected by 1,4-ndpaH_(2)^(2-).Both compounds 4 and 5 obtained by the introduction of flexible ligands during the synthesis show a 2D layered structure,which is formed by ligand crosslinking double metal chains.Interestingly,In 4,flexible 1,2-bix was singly protonated,as vip molecules,filled between layer and layer,while flexible ligand 1,3-dpp is absent in 5.Photophysical measurements indicate that compounds 1-5 show ligand-centered emissions.
文摘To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2.
基金financial support from the National Key Research and Development Program of China(No.2021YFF0600704).
文摘The hydroformylation of olefins,known as the"oxo reaction",involves the use of syngas(CO/H_(2))to produce aldehyde with an additional carbon atom.However,side reactions such as the isomerization or hydrogenation of olefins often result in unexpected products and other by-products.Recent efforts in developing efficient ligands represent the most effective approach to addressing these challenges.In this study,we described a Bis-OPNN phosphorus ligand facilitated Rh-catalyzed hydroformylation with a high degree of linear selectivity across various olefins.Under mild conditions,a broad range of olefins were efficiently converted into linear aldehydes with high yields and excellent regioselectivity.The protocol also showed impressive functional group tolerance and was successfully applied to modify drugs and natural products,including the total synthesis of(±)-crispine A.Preliminary mechanistic studies revealed that this Bis-OPNN phosphorus ligand anchoring the rhodium catalyst is crucial for controlling the linear selectivity.
基金supported by the National Natural Science Foundation of China(Nos.52300120 and 52070144)the Fundamental Research Funds for the Central Universities(No.22120240465).
文摘Regulating the photo-response region of iron metal-organic frameworks(Fe-MOFs)is a viable strategy for enhancing their practical application in the visible-light driven photo-Fenton-like process.This study developed a novel pyrazine-based Fe-MOFs(MIL-101(Fe)-Pz)by substituting the 1,4-dicarboxybenzene acid ligands in typical MIL-101(Fe)with 2,5-pyrazinedicarboxylic acid(PzDC),in which sodium acetate was used as coordinative modulator to control the crystal size(2–3μm).The incorporation of Fe-pyridine N coordination structures originated from PzDC ligands gave MIL-101(Fe)-Pz narrowed band gap(1.45 eV)than MIL-101(Fe)(2.54 eV)resulting in improved visible-light adsorption capacity(λ>420 nm),and also increased the proportion of Fe(Ⅱ)in the Fe-clusters.Thus MIL-101(Fe)-Pz exhibited a synergistic enhanced photo-Fenton-like catalytic performance under visible-light irradiation.The MIL-101(Fe)-Pz/H_(2)O_(2)/Vis system could degrade 99%of sulfamethoxazolewithin 30min,whichwas 10-fold faster than that of the pristine MIL-101(Fe),it also effectively removed other organic micropollutants with high durability and stability.Mechanistic analysis revealed that the PzDC ligands substitution decreased the band gap of MIL-101(Fe),giving MIL-101(Fe)-Pz appropriate band structure(-0.40∼1.05 V vs.NHE)which can cover several light-driven process for the generation of reactive oxygen species,including Fe(Ⅲ)reduction and H_(2)O_(2) activation for accelerating•OH generation,as well as oxygen reduction reaction for generating H_(2)O_(2),O_(2)^(•−) and ^(1)O_(2).This study highlights the role of pyridine-N containing ligands in regulating the band structure of Fe-MOFs,providing valuable guidance for the design of Fe-MOFs photocatalysts.
基金the National Key R&D Program of China(No.2022YFB4101900)National Natural Science Foundation of China(Nos.22278305,U21B2096)Natural Science Foundation of Tianjin City(No.23JCZDJC00040)。
文摘A strategy for copper-catalyzed and biphosphine ligand controlled boracarboxylation of 1,3-dienes and CO_(2) with 3,4-selectivity was developed.The Cu Cl coupled with DPPF(1,1-bis(diphenylphosphino)ferrocene)was assigned to be the best catalyst,with 84%yield and exclusive3,4-selectivity.The ligand effect on both catalytic activity and regioselectivity of boracarboxylation was disclosed,which is rarely reported in any copper catalyzed boracarboxylation.The borocupration process is revealed to be a vital step for the biphosphine participated boracarboxylation of 1,3-dienes with CO_(2).The minimal substrate distortion occurring in 3,4-borocupration favors the 3,4-regioselectivity of boracarboxylation.The“pocket”confinement and suitableβ_(n)(92°–106°)of bisphosphine ligands are demonstrated to be in favour of the interaction between LCu-Bpin complex(the catalytic precursor)and1,3-diene substrate to decrease their interaction energyΔE_(int)(ζ)in 3,4-borocupration,thus promoting the 3,4-boracarboxylation.
文摘Crystalline metal cluster-based organic-inorganic hybrid materials have emerged as a significant frontier in materials chemistry due to their unique structural designability and tunable properties.The bifunctional ligand 2-(hydroxymethyl)-2-(4-pyridyl)-1,3-propanediol(H3L),featuring both hard hydroxyl donors on one side and a soft pyridyl group on the other side,enables selective metal coordination via hard-soft acid-base(HSAB)theory and directs hierarchical metal cluster assembly.This review systematically summarizes the recent advances on metal cluster-based materials coordinated by H_(3)L,including their syntheses,crystal structures,and related physicochemical properties.
基金support from the National Key Research and Development Program of China(2022YFE0206000)the National Natural Science Foundation of China(U2001219,51973064)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2023B1515040003,2024A1515010262)the Natural Science Foundation of Guangdong Province(2023B1212060003)the Open Project Program of Wuhan National Laboratory for Optoelectronics(NO.2021WNLOKF014)the State Key Lab of Luminescent Materials and Devices,South China University of Technology(Skllmd-2023-05).
文摘Formamidinium lead bromide(FAPbBr_(3))perovskite nanocrystals(NCs)are promising for display and lighting due to their ultra-pure green emission.However,the thermal quenching will exacerbate their performance degradation in practical applications,which is a common issue for halide perovskites.Here,we reported the heat-resistant FAPbBr_(3)NCs prepared by a ligand-engineered room-temperature synthesis strategy.An aromatic amine,specificallyβ-phenylethylamine(PEA)or 3-fluorophenylethylamine(3-F-PEA),was incoporated as the short-chain ligand to expedite the crystallization rate and control the size distribution of FAPbBr_(3)NCs.Employing this ligand engineering approach,we synthesized high quality FAPbBr_(3)NCs with uniform grain size and reduced long-chain alkyl ligands,resulting in substantially suppressed thermal quenching and enhanced carrier transportation in the perovskite NCs films.Most notably,more than 90%of the room temperature PL intensity in the 3-F-PEA modified FAPbBr_(3)NCs film was preserved at 380 K.Consequently,we fabricated ultra-pure green EL devices with a room temperature external quantum efficiency(EQE)as high as 21.9%at the luminance of above 1,000 cd m^(-2),and demonstrated less than 10%loss in EQE at 343 K.This study introduces a novel room temperature method to synthesize efficient FAPbBr_(3)NCs with exceptional thermal stability,paving the way for advanced optoelectronic device applications.
基金supported by the National Natural Science Foundation of China(No.21975151)China Postdoctoral Science Foundation(No.2023M733452).
文摘Pt-rare-earth(PtRE)alloys are considered to be highly promising catalysts for oxygen reduction reaction(ORR)in acidic electrolytes.However,the wet-chemical synthesis of PtRE nanoalloys still faces significant challenges.The precise reaction mechanism for ORR of these catalysts is still unclear on significant aspects involving the rate-determining step and the nature of the ligand effect.Herein,we report a class of solvothermal synthesis of PtRE(RE is Dy or La)nanoalloys.Such PtRE nanoalloys here are active and stable in acidic media,with both high mass activities enhanced by 2-5 times relative to commercial Pt/C catalyst and high stabilities indicative of the little activity decay and negligible structure change after 10,000 cycles.Density functional theory calculations firmly confirm that the ligand effect of RE elements accelerates an O-O bond scission and steers the rate-determining steps from OH^(*)+H^(+)+e-→H_(2)O(on pure Pt surface)to HOOH^(*)+H^(+)+e-→OH^(*)+H_(2)O(on the PtRE nanoalloy surface)for the fast reaction kinetics,which could be fine-tuned by regulating the RE electronic structures and consequently endows the maximal rate of ORR catalysis with PtDy alloy catalysts.
文摘BACKGROUND In recent years,emerging clinical research has prioritized assessment of combined therapeutic efficacy and safety parameters when programmed death 1 or its ligand(PD-1/L1)inhibitors are incorporated into first-line standard-of-care(SOC)therapy for metastatic colorectal cancer(mCRC).However,data obtained from these trials demonstrated conflicting evidence concerning survival benefits and clinical outcomes.AIM To evaluate the therapeutic impact and safety parameters of combining PD-1/L1 inhibitors with SOC protocols as first-line treatment for mCRC.METHODS Four biomedical databases(PubMed,Embase,Cochrane Library,Web of Science)were systematically interrogated to identify eligible studies published up to October 12,2024.The analysis focused on evaluating the primary outcome of overall survival(OS)in the mCRC population with secondary outcomes of progression-free survival(PFS),overall response rate(ORR),and incidence rate of grade≥3 adverse events.Additionally,we performed exploratory analyses in the microsatellite stable/mismatch repair-proficient(MSS/pMMR)subpopulation,based on a subset of the included studies.Subgroup analyses according to PD-1/L1 inhibitor use were conducted in both the overall population and the MSS/pMMR subgroup.RESULTS This pooled analysis incorporated six randomized controlled trials involving 675 patients with mCRC receiving first-line therapy.The combination of PD-1/L1 inhibitors with SOC regimens demonstrated a significant PFS advantage over SOC monotherapy in intention-to-treat populations[hazard ratio(HR)=0.8,95%confidence interval(CI):0.65-0.98,P=0.033].Nevertheless,the MSS/pMMR subgroup showed no PFS benefit(HR=0.83,95%CI:0.67-1.03,P=0.091),and no cohort exhibited OS improvement(intention-to-treat:HR=0.84,95%CI:0.66-1.05,P=0.124;MSS/pMMR:HR=0.79,95%CI:0.60-1.03,P=0.083).Comparable outcomes were observed for ORR(risk ratio=1.03,95%CI:0.90-1.17,P=0.711)and incidence rate of grade≥3 adverse events(risk ratio=1.12,95%CI:0.93-1.36,P=0.245)between treatment arms.CONCLUSION The findings indicated that integrating PD-1/L1 blocking agents with SOC regimens for mCRC as first-line treatment failed to demonstrate significant improvements in ORR.Existing clinical data remain inadequate to establish OS advantages,particularly in patients with MSS/pMMR,despite exhibiting manageable toxicity profiles.Subsequent confirmation through rigorously designed phase III clinical trials remains essential to verify these therapeutic outcomes.
基金supported by the Natural Science Foundation of Hunan Province(No.2023JJ30650)the Central South University Innovation-Driven Research Programme(No.2023CXQD061)。
文摘The atomic-level exploration of structure-property correlations poses significant challenges in establishing precise design principles for electrocatalysts targeting efficient CO_(2)conversion.This study demonstrates how controlled exposure of metal sites governs CO_(2)electroreduction performance through two octanuclear bismuth-oxo clusters with distinct architectures.The Bi_(8)-DMF cluster,constructed using tert–butylthiacalix[4]arene(TC4A)as the sole ligand,features two surface-exposed Bi active sites,while the dual-ligand Bi_(8)-Fc(with TC4A/ferrocene carboxylate)forms a fully encapsulated structure.Electrocatalytic tests reveal Bi_(8)-DMF achieves exceptional formate selectivity(>90%Faradaic efficiency)across a broad potential window(-0.9 V to-1.6 V vs.RHE)with 20 h stability,outperforming Bi_(8)-Fc(60%efficiency at-1.5 V).Theoretical calculations attribute Bi_(8)-DMF's superiority to exposed Bi sites that stabilize the critical*OCHO intermediate via optimized orbital interactions.This work provides crucial guidance for polynuclear catalyst design:moderate exposure of metal active sites significantly enhances CO_(2)reduction performance.
基金supported by the National Key R&D Program of China(2022YFB4200500)the Key Research and Development Plan Project of Anhui Province(2022h11020014)+3 种基金Collaborative Innovation Program of Hefei Science Center,CAS(2022HSCCIP006)the CASHIPS Director’s Fund(YZJJ201902 and YZJJZX202018)the Anhui Provincial Natural Science Foundation(2408085MB029)the Natural Science Foundation of Hebei Province of China(B2024402018)。
文摘Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge transport layers often lead to reduced power conversion efficiency(PCE).Surface treatment is an effective strategy but the passivating ligands usually bind with a single active site.The resulted dense packing of resistive passivators perpendicular to the surface is detrimental to charge transport.Here,we present a passivator that can bind to two neighboring lead(Ⅱ)ion(Pb^(2+))defect sites simultaneously with an aligned parallel mode to the perovskite surface,effectively suppressing the surface trap density and preventing the aggregation.The target device fulfills a PCE of 25.1%and maintains over 85% of the initial efficiency after 800 h of exposure to a relative humidity(RH)of 65%±5%.
