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1.
Cell Rep ; 43(4): 114065, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38578828

RESUMO

Epigenetic modification shapes differentiation trajectory and regulates the exhaustion state of chimeric antigen receptor T (CAR-T) cells. Limited efficacy induced by terminal exhaustion closely ties with intrinsic transcriptional regulation. However, the comprehensive regulatory mechanisms remain largely elusive. Here, we identify class I histone deacetylase inhibitors (HDACi) as boosters of CAR-T cell function by high-throughput screening of chromatin-modifying drugs, in which M344 and chidamide enhance memory maintenance and resistance to exhaustion of CAR-T cells that induce sustained antitumor efficacy both in vitro and in vivo. Mechanistically, HDACi decrease HDAC1 expression and enhance H3K27ac activity. Multi-omics analyses from RNA-seq, ATAC-seq, and H3K27ac CUT&Tag-seq show that HDACi upregulate expression of TCF4, LEF1, and CTNNB1, which subsequently activate the canonical Wnt/ß-catenin pathway. Collectively, our findings elucidate the functional roles of class I HDACi in enhancing CAR-T cell function, which provides the basis and therapeutic targets for synergic combination of CAR-T cell therapy and HDACi treatment.


Assuntos
Aminopiridinas , Inibidores de Histona Desacetilases , Via de Sinalização Wnt , Inibidores de Histona Desacetilases/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Humanos , Camundongos , Benzamidas/farmacologia , Linhagem Celular Tumoral , Imunoterapia Adotiva/métodos , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Linfócitos T/imunologia , Histona Desacetilase 1/metabolismo
2.
J Colloid Interface Sci ; 665: 399-412, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38537588

RESUMO

Photocatalytic selective oxidation plays an important role in developing green chemistry. However, it is challenging to design an efficient photocatalyst for controlling the selectivity of photocatalytic oxidation reaction and exploring its detailed mechanism. Here, we synthesized three conjugated microporous polymers (CMPs) with D-A structures, named M-SATE-CMPs (MZn, Cu and Co), with different d-band centers based on different metal centers, resulting in the discrepancy in adsorption and activation capacities for the reactants, which produces the selectivity of ß-keto esters being catalyzed into α-hydroperoxide ß-keto esters (ROOH) or to α-hydroxyl ß-keto esters (ROH). Density functional theory (DFT) calculations also demonstrate that the adsorption and activation capacities of the metal active centers in M-SATE-CMPs (MZn, Cu and Co) for ROOH are the key factors to influence the photocatalytic selective oxidation of ß-keto ester. This study provides a promising strategy for designing a metallaphotoredox catalyst whose photocatalytic selectivity depends on the d-band center of metal site in the catalyst.

3.
Cell Rep Med ; 5(2): 101400, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38307031

RESUMO

Chimeric antigen receptor (CAR)-T therapy has shown superior efficacy against hematopoietic malignancies. However, many patients failed to achieve sustainable tumor control partially due to CAR-T cell exhaustion and limited persistence. In this study, by performing single-cell multi-omics data analysis on patient-derived CAR-T cells, we identify CD38 as a potential hallmark of exhausted CAR-T cells, which is positively correlated with exhaustion-related transcription factors and further confirmed with in vitro exhaustion models. Moreover, inhibiting CD38 activity reverses tonic signaling- or tumor antigen-induced exhaustion independent of single-chain variable fragment design or costimulatory domain, resulting in improved CAR-T cell cytotoxicity and antitumor response. Mechanistically, CD38 inhibition synergizes the downregulation of CD38-cADPR -Ca2+ signaling and activation of the CD38-NAD+-SIRT1 axis to suppress glycolysis. Collectively, our findings shed light on the role of CD38 in CAR-T cell exhaustion and suggest potential clinical applications of CD38 inhibition in enhancing the efficacy and persistence of CAR-T cell therapy.


Assuntos
Neoplasias , Anticorpos de Cadeia Única , Humanos , Linfócitos T , Imunoterapia Adotiva/métodos , Antígenos de Neoplasias/metabolismo
4.
Cell Metab ; 36(1): 176-192.e10, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38171332

RESUMO

The efficacy of chimeric antigen receptor (CAR) T cell therapy is hampered by relapse in hematologic malignancies and by hyporesponsiveness in solid tumors. Long-lived memory CAR T cells are critical for improving tumor clearance and long-term protection. However, during rapid ex vivo expansion or in vivo tumor eradication, metabolic shifts and inhibitory signals lead to terminal differentiation and exhaustion of CAR T cells. Through a mitochondria-related compound screening, we find that the FDA-approved isocitrate dehydrogenase 2 (IDH2) inhibitor enasidenib enhances memory CAR T cell formation and sustains anti-leukemic cytotoxicity in vivo. Mechanistically, IDH2 impedes metabolic fitness of CAR T cells by restraining glucose utilization via the pentose phosphate pathway, which alleviates oxidative stress, particularly in nutrient-restricted conditions. In addition, IDH2 limits cytosolic acetyl-CoA levels to prevent histone acetylation that promotes memory cell formation. In combination with pharmacological IDH2 inhibition, CAR T cell therapy is demonstrated to have superior efficacy in a pre-clinical model.


Assuntos
Antioxidantes , Neoplasias , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Isocitrato Desidrogenase , Histonas/metabolismo , Acetilação , Linfócitos T , Neoplasias/metabolismo , Mitocôndrias/metabolismo
5.
Dalton Trans ; 52(28): 9655-9663, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37381747

RESUMO

Natural gas plays an important role in daily life and the petrochemical industry, but there are often large amounts of impurities which prevent the full use of methane in natural gas. Developing excellent adsorbents to purify CH4 from multi-component mixtures is crucial, but also faces great challenges. Here, by utilizing a ligand conformation preorganization strategy, we employ a flexible nonplanar hexacarboxylate ligand with C2 symmetry to successfully construct a robust microporous metal-organic framework {[Cu3(bmipia)(H2O)3]·(DMF)(CH3CN)2}n (GNU-1, bmipia = 5-[N,N-bis(5-methylisophthalic acid)amion] isophthalate) with an unprecedented topology. More importantly, the obtained GNU-1 not only exhibits good stability in acid-base and water environments, but also shows potential utility as an adsorbent for efficient separation and purification of natural gas under ambient conditions. The adsorption isotherms of GNU-1a (activated GNU-1) exhibit strong binding affinities for C2H6 and C3H8, a remarkable uptakes of C3H8 (6.64 mmol g-1) and C2H6 (4.6 mmol g-1) and an excellent selectivity of 330.1 and 17.5 for C3H8/CH4 and C2H6/CH4 mixtures, respectively, at 298 K and 1 bar. The breakthrough experiments demonstrate that the ternary CH4/C2H6/C3H8 mixtures are completely separated using a fixed-bed separator packed with GNU-1a at ambient temperature and also show great potential for recovering the C2H6 and C3H8 contents from natural gas. Finally, Grand Canonical Monte Carlo simulations are adopted to ascertain potential gas adsorption mechanisms. This work proves the feasibility of optimizing the structure and pore size of MOF materials by regulating the conformation of ligands for application in the field of light hydrocarbon adsorption/separation.

6.
Front Chem ; 10: 1025030, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339039

RESUMO

The importance of electroceramics is well-recognized in applications of high energy storage density of dielectric ceramic capacitors. Despite the excellent properties, lead-free alternatives are highly desirous owing to their environmental friendliness for energy storage applications. Herein, we provide a facile synthesis of lead-free ferroelectric ceramic perovskite material demonstrating enhanced energy storage density. The ceramic material with a series of composition (1-z) (0.94Na0.5Bi0.5TiO3-0.06BaTiO3)-zNd0.33NbO3, denoted as NBT-BT-zNN, where, z = 0.00, 0.02, 0.04, 0.06, and 0.08 are synthesized by the conventional solid-state mix oxide route. Microphases, microstructures, and energy storage characteristics of the as-synthesized ceramic compositions were determined by advanced ceramic techniques. Powder X-ray diffraction analysis reveals pure single perovskite phases for z = 0 and 0.02, and secondary phases of Bi2Ti2O7 appeared for z = 0.04 and 0.08. Furthermore, scanning electron microscopy analysis demonstrates packed-shaped microstructures with a reduced grain size for these ceramic compositions. The coercive field (Ec) and remnant polarization (Pr) deduced from polarization vs. electric field hysteresis loops determined using an LCR meter demonstrate decreasing trends with the increasing z content for each composition. Consequently, the maximum energy storage density of 3.2 J/cm3, the recoverable stored energy of 2.01 J/cm3, and the efficiency of 62.5% were obtained for the z content of 2 mol% at an applied electric field of 250 kV/cm. This work demonstrates important development in ceramic perovskite for high power energy storage density and efficiency in dielectric capacitors in high-temperature environments. The aforementioned method makes it feasible to modify a binary ceramic composition into a ternary system with highly enhanced energy storage characteristics by incorporating rare earth metals with transition metal oxides in appropriate proportions.

7.
Adv Sci (Weinh) ; 9(9): e2103508, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35032108

RESUMO

Chimeric antigen receptor (CAR) T cells are potent agents for recognizing and eliminating tumors, and have achieved remarkable success in the treatment of patients with refractory leukemia and lymphoma. However, dysfunction of T cells, including exhaustion, is an inevitable obstacle for persistent curative effects. Here, the authors initially found that calcium signaling is hyperactivated via sustained tonic signaling in CAR-T cells. Next, it is revealed that the store-operated calcium entry (SOCE) inhibitor BTP-2, but not the calcium chelator BAPTA-AM, markedly diminishes CAR-T cell exhaustion and terminal differentiation of CAR-T cells in both tonic signaling and tumor antigen exposure models. Furthermore, BTP-2 pretreated CAR-T cells show improved antitumor potency and prolonged survival in vivo. Mechanistically, transcriptome and metabolite analyses reveal that treatment with BTP-2 significantly downregulate SOCE-calcineurin-nuclear factor of activated T-cells (NFAT) and glycolysis pathways. Together, the results indicate that modulating the SOCE-calcineurin-NFAT pathway in CAR-T cells renders them resistant to exhaustion, thereby yielding CAR products with enhanced antitumor potency.


Assuntos
Calcineurina , Leucemia , Calcineurina/metabolismo , Calcineurina/farmacologia , Sinalização do Cálcio , Glicólise , Humanos , Leucemia/metabolismo , Leucemia/terapia , Linfócitos T/metabolismo
8.
J Am Chem Soc ; 143(34): 13731-13737, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34410122

RESUMO

The controlling synthesis of novel nanoclusters of noble metals (Au, Ag) and the determination of their atomically precise structures provide opportunities for investigating their specific properties and applications. Here we report a novel silver nanocluster [Ag307Cl62(SPhtBu)110] (Ag307) whose structure is determined by X-ray single crystal diffraction. The structure analysis shows that nanocluster Ag307 contains a Ag167 core, a surface shell of [Ag140Cl2S110], and a Cl60 intermediate layer located between Ag167 and [Ag140Cl2S110]. It is a first example that such many chlorides are intercalated into a Ag nanocluster. Chlorides are released in situ from solvent CHCl3. Nanocluster Ag307 exhibits superstability. Differential pulse voltammetry experiment reveals that Ag307 has continuous charging/discharging behavior with a capacitance value of 1.39 aF, while the Ag307 has a surface plasmonic feature. These characteristics show that Ag307 is of metallic behavior. However, its electron paramagnetic resonance (EPR) spectra display a spin magnetic behavior which could be originated from the unpassivated dangling bonds of surface atoms. The direct capture of EPR signals can be attributed to the Cl- intercalating layer which partly suppresses the electronic interactions between core and surface atoms, resulting in the relatively independent electronic states for core and surface atoms.

9.
J Hematol Oncol ; 14(1): 113, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34289897

RESUMO

Relapses of CD19-expressing leukemia in patients who achieved initial remission after CART cell treatment have been reported to correlate with poor CART cells persistence. Sustained tonic signaling or strong activation drives CART cell differentiation and exhaustion, which limit the therapeutic efficacy and persistence of CART cells. Here, we identified dasatinib as the optimal candidate to prevent or reverse both CD28/CART and 4-1BB/CART cell differentiation and exhaustion during ex vivo expansion, which profoundly enhanced the therapeutic efficacy and in vivo persistence. Moreover, strong activation-induced CART cells differentiation, exhaustion and apoptosis driven by CD3/CD28 stimulation or antigen exposure were dramatically prevented or reversed by dasatinib treatment. Mechanistically, dasatinib markedly reduced the phosphorylation of Src and Lck, and downregulated the expression of genes involved in CAR signaling pathways, which resulted in the optimization of cell differentiation, exhaustion and apoptosis-related gene expression. Our study proposes a promising pharmacological approach for optimizing CART cells manufacture, and provides an experimental basis for reinvigorating CART cells in clinical application.


Assuntos
Dasatinibe/farmacologia , Imunoterapia Adotiva , Inibidores de Proteínas Quinases/farmacologia , Linfócitos T/efeitos dos fármacos , Antineoplásicos/farmacologia , Antígenos CD28/imunologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Humanos , Imunoterapia Adotiva/métodos , Ativação Linfocitária/efeitos dos fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
10.
Cancer Immunol Res ; 9(9): 1061-1070, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34290048

RESUMO

Chimeric antigen receptor (CAR) T-cell therapies that target either CD19 or CD22 alone have potent antilymphoma effects. However, antigen escape-mediated relapse often occurs. CAR T cells targeting both CD19 and CD22 may overcome this limitation. In this study, we developed bispecific CAR T cells simultaneously recognizing CD19- and CD22-expressing targets and assessed their safety and efficacy profiles in patients with relapsed/refractory aggressive B-cell lymphoma. Twenty-four patients were screened, and 16 were found eligible for the study. CAR T-cell-associated toxicities were recorded. Responses, overall survival (OS), and progression-free survival (PFS) were assessed. Of the 16 eligible patients, 14 (87.5%) achieved objective response and 10 (62.5%) achieved complete response (CR). The 2-year OS and PFS rates were 77.3% and 40.2%, respectively. Achieving CR (P = 0.046) and the number of prior chemotherapy lines (n = 2; P = 0.047) were independent prognostic factors associated with favorable PFS. The 2-year OS and PFS among patients who achieved CR were higher than among those who did not (P = 0.015 and P < 0.001, respectively). The 2-year PFS among patients who received two prior lines of chemotherapy was higher than that among patients who received more than two lines of chemotherapy (P = 0.049); OS did not differ between the groups. Severe grade 4 cytokine-release syndrome (CRS) was observed in 1 patient; 4 and 11 patients had grades 1 and 2 CRS, respectively. No patients developed neurotoxicity. CD19/CD22 dual-targeted CAR T cells may be a safe, potent antilymphoma cell-based targeted immunotherapy.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Linfoma de Células B/terapia , Recidiva Local de Neoplasia/terapia , Receptores de Antígenos Quiméricos , Animais , Deriva e Deslocamento Antigênicos , Antígenos CD19/imunologia , Linhagem Celular , Feminino , Humanos , Imunoterapia Adotiva , Camundongos , Intervalo Livre de Progressão , Lectina 2 Semelhante a Ig de Ligação ao Ácido Siálico , Linfócitos T/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Polymers (Basel) ; 14(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35012117

RESUMO

The purpose of this work is to investigate the effects of copper (II) sulfate on the formaldehyde release and the mechanical properties of urea formaldehyde (UF) adhesive. Copper (II) sulfate has been used as a formaldehyde scavenger in UF resin, and its effects on the physical and chemical properties of UF adhesive have been studied. Moreover, the mechanical properties and formaldehyde release of plywood prepared with modified UF resin have been determined. The UF resin has been characterized by Fourier-transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). FTIR spectra showed that the addition of copper (II) sulfate to the UF resin does not affect the IR absorptions of its functional groups, implying that the structure of UF is not modified. Further results showed that the free formaldehyde content of the UF resin incorporating 3% copper (II) sulfate was 0.13 wt.%, around 71% lower than that of the untreated control UF adhesive. With a copper (II) sulfate content of 3%, the formaldehyde release from treated plywood was 0.74 mg·L-1, around 50% lower than that from the control UF adhesive, and the bonding strength reached 1.73 MPa, around 43% higher than that of the control.

12.
J Inorg Biochem ; 211: 111175, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32858466

RESUMO

The rare earth metal Gd(III), Yb(III), Lu(III), Eu(III), Tb(III) and Ho(III) complexes 1-6 with 2-((2-(pyridin-2-yl)hydrazono)methyl)quinolin-8-ol (H-L) as ligands were synthesized. The in vitro cytotoxicity assay indicated that the cytotoxicity of 1 was equivalent to cisplatin and higher than that of H-L and other complexes towards T24 tumor cells. The mechanism study indicated that 1 caused significant up-regulation of the proteins p27, p21 and p53 in T24 cells and cell cycle arrest in G2 phase. In addition, 1 induced effective T24 cells apoptosis via mitochondrial dysfunction pathway, which was indicated by changes in mitochondrial membrane potential (Δψ), reactive oxygen species (ROS), intracellular Ca2+ and the mitochondria-related proteins (including cytochrome C (Cyt C), B-cell lymphoma-2 (Bcl-2), Bcl-2-associated x (Bax) and apoptotic protease activating factor-1 (Apaf-1)). Moreover, 1 could activate caspase-3/8/9 in T24 cells. Therefore, complex 1 is a promising and potent anticancer drug candidate.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Metais Terras Raras/farmacologia , Mitocôndrias/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Oxiquinolina/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Complexos de Coordenação/química , Humanos , Metais Terras Raras/química , Neoplasias/química , Neoplasias/metabolismo , Oxiquinolina/farmacologia , Transdução de Sinais/efeitos dos fármacos
13.
Inorg Chem ; 59(3): 1653-1659, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31965792

RESUMO

A discrete tetrahedral indium cage, {[In12(µ3-OH)4(HCO2)24(tcma)4]} (In12-GL), was synthesized solvothermally by the reaction of indium nitrate with the tripodal tricarboxylic acid ligand N,N,N-tris{(2'-carboxy[1,1'-biphenyl]-4-yl)methyl}methylammonium chloride ([H3tcma]+Cl). This cage consists of four trimeric units [In3(µ3-OH)(µ2-CO2)3(µ2-HCO2)3] and four [tcma]2- ligands, which all perform as 3-connection nodes to bridge each other, resulting in a tetrahedral cage structure. The trimeric unit [In3(µ3-OH)(µ2-CO2)3(µ2-HCO2)3] is observed for the first time in the family of In-based metal-organic structures and can be considered as an evolution of a 6-connected [In3(µ3-O)(µ2-CO2)6] unit. Each In3+ is terminally coordinated by a µ1-HCO2 group. This cage contains potential Lewis acidic/basic active sites endowed by In3+ ions as Lewis acidic sites and the uncoordinated oxygen atoms of µ1-HCO2 moieties as Lewis basic sites and was explored as an effective heterogeneous catalyst in the cycloaddition of CO2 with epoxides and the Strecker reaction for amino nitriles. These catalytic reactions were deduced to happen on the surface of the In12-GL cage.

14.
Bone Marrow Transplant ; 54(12): 2072-2080, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31383996

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy has displayed potent anti-leukemia activity in acute lymphocytic leukemia (ALL), acting as a new ray of hope to refractory/relapsed patients. However, the influence of CAR-T therapy on host immune system has not been well elucidated. Thus, We applied high-throughput T cell receptor ß chain sequencing to track the dynamic change of T-cell repertoire induced by CAR-T therapy in B-cell ALL patients. Six Chinese patients achieving complete remission were under observation, whose blood samples, bone marrow samples and infused CAR-T samples were collected at serial time points before and after CAR-T therapy. We observed decreased TCR diversity and increased clonality of T-cell repertoire in both peripheral blood and bone marrow after CAR-T administration. The persistent T cell clones in blood and bone marrow expanded following leukemic cell destruction and were barely detected in CAR T-cell pool. For the first time, our results demonstrated CAR-T therapy could stimulate the clonal proliferation of CAR-negative T cells in patients. Considering other groups' animal results indicating that CAR-T therapy could facilitate the proliferation of tumor antigen-specific T cells and that the emergence of these T cell clones followed the destruction of leukemic cells, they are most likely tumor antigen-specific.


Assuntos
Imunoterapia Adotiva/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Linfócitos T/imunologia , China , Feminino , Humanos , Masculino
15.
Pak J Pharm Sci ; 31(5(Special)): 2191-2195, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30463811

RESUMO

At present, the drugs used in the field of postoperative analgesia are mainly opioids. The three analgesics selected in this study are opioid receptor agonists, but opioids are easy to produce adverse reactions. In this study, the visual analogue score of resting pain and dynamic pain at two time points of 4 hours and 12 hours was observed in group B and group C were higher than that in group A (P<0.05), indicating that the analgesic effect of dezocine was better. Follow up observation of adverse reactions, dezocine group patients had fewer adverse reactions (P<0.05). It can be seen that although there are certain differences in the mechanism of these three drugs, there are some relevant evidence that all three drugs can be used safely and effectively for postoperative obstetric analgesia.


Assuntos
Analgésicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Butorfanol/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Tetra-Hidronaftalenos/uso terapêutico , Tramadol/uso terapêutico , Adulto , Analgésicos Opioides/uso terapêutico , Cesárea/métodos , Feminino , Humanos , Masculino , Medição da Dor/métodos , Gravidez
17.
Nanoscale ; 10(2): 515-519, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29239443

RESUMO

A first and stable Ag-P superatom nanocluster [Ag15(N-triphos)4(Cl4)](NO3)3 (1) has been successfully synthesized and characterized. X-ray analysis shows that this Ag15 cluster has a hexacapped body-centered cubic (bcc) framework which is consolidated by four tripodal N-triphos ligands. The identity of 1 is confirmed by high resolution ESI-MS. Cluster 1 has an electronic and geometric shell closure structure with 8 free electrons, matching the stability idea of superatom theory for a nanocluster. DFT calculation of this Ag15 cluster reveals the superatom feature with a 1S21P6 configuration. The chelation of multidentate phosphines enhances the stability of this Ag15 cluster. The AgAg distances between the centered and the vertical Ag atoms of this bcc (Ag@Ag8) are in the range of 2.57-2.71 Å, and the distances between the face-capped and the vertical silver atoms are in the range of 2.84-2.92 Å, showing strong AgAg interactions within this cluster core. This superatom complex exhibits a relatively high thermal and photolytic stability.

18.
Chem Commun (Camb) ; 52(30): 5293-6, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-27001898

RESUMO

A fish-basket-shaped [Co24] cluster, [Co24(µ3-O)4(ampc)4(µ3-OH)4(µ2-OH)4(NO3)5(HCO2)22(H2O)10]·[(HCO2)·2(CH3OH)·x(H2O)], was woven by bridging oxygen atoms from O(2-), OH(-), NO3(-) and HCO2(-) groups, and stabilized terminally by a semi-rigid organic ligand 4',4'-[(dimethylamino)dimethylene]-bis[(1,1'-biphenyl)-2-carboxylate] (ampc(-)). Magnetic analyses indicate that the [Co24] cluster exhibits two types of spin canting orders, spin flop and a small hysteresis with a coercive field of ca. 661 Oe and a remanent magnetization of 0.466 Nß.

19.
Dalton Trans ; 45(12): 4993-7, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26936460

RESUMO

Two metallocycles, {Cu8(bp)4(OH)4(H2O)4(ClO4)4} (1) and {Cu20(bp)20} (2), were afforded by the reactions of the semi-flexible tridentate ligand bis(2-hydroxybenzyl)amine (H2bp) with Cu(ClO4)2·6H2O and Cu(OAc)2·H2O. Complex 1 has a saddle-shaped cyclic structure and complex 2 has a nanosized wheel-shaped structure. The two compounds consist of [Cu(bp)] units.

20.
Toxicol Rep ; 2: 205-209, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28962353

RESUMO

BACKGROUND: Ketamine is a controlled substance and often illegally used as a recreational drug primarily by young adults. Increasing ketamine abusers associated with lower urinary tract symptoms have been reported at hospitals in recent years. Here we used a murine model to explore the changes of bladder in order to elucidate its pathogenesis. METHODS: ICR mice were randomly distributed into control and ketamine groups and received daily intraperitoneal injection of saline and ketamine (30 mg/kg), respectively. The bladders were excised and processed for histology at 4, 8 and 12 weeks. Tryptase and E-cadherin were investigated by immunohistochemistry in bladder tissues from ketamine-treated and control mice to assess the mast cell activation and junction protein expression. RESULTS: After ketamine treatment, the bladder changed to be hyperemic, inflamed, and with more fissures in mucosa. Compared with control group, the number of tryptase-positive mast cells significantly increased, which was 6.98 ± 2.89 and 23.00 ± 6.48 cells per field (100×) at 8 and 12 weeks, respectively (P = 0.016 and P = 0.003, respectively). Additionally, the expression of E-cadherin in ketamine-treated mice bladder tissue was significantly lower than that in the control tissues, P < 0.001. CONCLUSIONS: Increased mast cells in bladder wall and downregulated expression of E-cadherin junction protein in epithelial cells were probably associated with interstitial inflammation and fissures in mucosa. It implied that ketamine induced an interstitial cystitis.

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