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1.
Inorg Chem ; 62(29): 11287-11290, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37429008

RESUMO

In this work, a new alkaline-stable boron imidazolate framework (BIF-90) was rationally designed and successfully synthesized by solvothermal reaction. Due to its potential electrocatalytic active sites (Co, B, N, and S) and chemical stabilities, BIF-90 was explored as a bifunctional electrocatalyst toward electrochemical oxygen reactions, namely, oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). This work will open new avenues toward the design of stable, cheap, and more active BIFs as bifunctional catalysts.

2.
Inorg Chem ; 61(40): 15801-15805, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35913725

RESUMO

Metal-organic frameworks (MOFs) have been a focus of research because of their unique porous structure, but they are usually not directly for electrocatalysis. Herein, we prepared a special class of Fe/Zn/Mo-based trimetallic hybrid zeolitic imidazolate frameworks by in situ solvothermal synthesis that have the potential to act directly as highly efficient oxygen evolution reaction electrocatalysts. This work provides a foundation for the preparation of multimetal MOFs and expands the investigation of electrocatalysts.

3.
Inorg Chem ; 60(17): 13434-13439, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34423965

RESUMO

Herein, a Co(II) heteroatom metal-organic framework was successfully post-modified via unsaturated coordinated S precisely capturing Ni2+ on the surface of the porous structure. The newly pristine bimetallic MOFs have increasing active edge sites (Ni(II) and S), boosting electrocatalytic activity toward oxygen evolution reaction and hydrogen evolution reaction.

4.
Biochem Biophys Res Commun ; 516(3): 983-990, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31272718

RESUMO

Gallbladder carcinoma (GBC) is always diagnosed at an advanced stage, and patients often miss the opportunity for surgery. Gemcitabine (GEM) and platinum-based drugs, including oxaliplatin (OXA), are mainstays of chemotherapy. However, drug resistance causes treatment failure. Hence, salvage mechanisms are critical to improve outcomes. This study revealed the positive correlation between placenta-specific protein 8 (PLAC8) overexpression and PD-L1 overexpression in GBC. Given the roles of PLAC8 and PD-L1 in chemotherapy resistance, GEM-resistant and OXA-resistant cell lines (SGC966GR and SGC966OR, respectively) were established to test whether and how PLAC8 and PD-L1 function in chemotherapy resistance. Drug-insensitive SGC966GR and SGC966OR cells upregulated MRP and MDR1 and had high expression of PLAC8. PLAC8 blockade using siRNA reversed chemotherapy resistance and downregulated MRP and MDR1 in SGC966GR and SGC966OR cells, suggesting that PLAC8 mediates chemotherapy resistance in GBC. Consistent with the increased mRNA levels of PD-L1 after the acquisition of resistance, PLAC8 knockdown reduced PD-L1 mRNA expression in SGC966GR and SGC966OR cells. In conclusion, PLAC8 overexpression in GBC patients positively correlated with PD-L1 expression. PLAC8 conferred resistance to GEM and OXA by upregulating PD-L1 expression, and PLAC8 or PD-L1 blockade may have potential for overcoming chemotherapy resistance, providing therapeutic options for chemotherapy-refractory GBC patients.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/genética , Resistencia a Medicamentos Antineoplásicos/genética , Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Proteínas/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Vesícula Biliar/metabolismo , Vesícula Biliar/patologia , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Oxaliplatina/farmacologia , Proteínas/antagonistas & inibidores , Proteínas/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Gencitabina
5.
Inorg Chem ; 56(6): 3526-3531, 2017 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-28267315

RESUMO

We report a facile approach to prepare metal-nanocatalyst-incorporated carbon thin films with uniform size distribution via carbonization of surface-mounted metal-organic frameworks (SURMOFs) and metal oxo-clusters loaded SURMOF. The calcinated thin films have high performance of methylene blue degradation and the reduction of nitrobenzene. This study describes a general strategy for preparing various nanoparticle-impregnated porous carbon thin films for applications in catalysis.

6.
J Am Chem Soc ; 138(8): 2556-9, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26894381

RESUMO

We present the formation of the largest titanium-oxo cluster, [Ti42(µ3-O)60(OiPr)42(OH)12)](6-), with the first fullerene-like Ti-O shell structure. The {Ti42O60} core of this compound exemplifies the same icosahedral (Ih) symmetry as C60, the highest possible symmetry for molecules. According to the coordination environments, the Ti centers in this cluster can be arranged into a Platonic {Ti12} icosahedron and an Archimedean {Ti30} icosidodecahedron. The solution stability of this cluster was confirmed by electrospray ionization mass spectrometry. The spherical body of the {Ti42O60} core has an inside diameter of 1.05 nm and an outside diameter of 1.53 nm, which could be directly visualized by high-resolution transmission electron microscopy. Our results demonstrate that titanium oxide can also form fullerene-like shell structures.

7.
Inorg Chem ; 54(13): 6069-71, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26087002

RESUMO

A series of 3D neutral boron imidazolate frameworks (BIFs) with octahedral metal centers were synthesized based on the charge-balancing principle. Au-Pd nanoparticles (NPs) with a mean size of 2.12 nm were then successfully obtained and encapsulated in these BIF structures through the simultaneous reduction of Au(3+)/Pd(3+) ions by B-H bonds of tridentate boron ligands. The very small sizes of these Au-Pd NPs are attributed to the pore confinement effect of BIFs. This work not only brings new methodology for the construction of neutral BIFs but also suggests a new strategy for loading smaller-sized bimetallic NPs into BIFs.

8.
Chemistry ; 20(3): 644-8, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24415360

RESUMO

Three 2D luminescent isomeric porous coordination polymers are synthesized and characterized. Their luminescence properties can be modified by grinding and they can act as mechanochromic materials and their properties are probably related to the weak interactions of cuprophilicity and π-π interactions.


Assuntos
Polímeros/química , Complexos de Coordenação/química , Cobre/química , Cristalografia por Raios X , Substâncias Luminescentes , Conformação Molecular , Porosidade , Teoria Quântica
9.
Inorg Chem ; 52(1): 12-4, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23244571

RESUMO

Two isomeric two-dimensional copper(I) coordination polymer materials based on an in situ generated 5-(3-pyridyl)tetrazole ligand show similar layer structures but distinct photoluminescent and photocatalytic properties, which present an interesting comparative study on the structure-property correlation between isomeric materials.


Assuntos
Corantes/química , Cobre/química , Polímeros/química , Catálise , Modelos Moleculares , Processos Fotoquímicos , Tetrazóis/química
10.
Dalton Trans ; 52(31): 10672-10676, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37522431

RESUMO

[NHC → GeN(Ar)Cu2NAr]2, the formal adduct of germanium analogue of organic isonitrile [GeNAr] with Cu(I) imide [(Cu2NAr)2] (Ar = 2,6-iPr2C6H3) was prepared from the N-heterocyclic carbene (NHC) stabilized acyclic germylene Ge[N(H)Ar]2 by reacting with two equivalents of nBuLi and CuCl(PPh3)3. As elucidated by X-ray crystal structural characterization, the two separated [GeNAr] moieties interacted with [(Cu2NAr)2] core in the side-on mode.

11.
Chem Asian J ; 17(13): e202200141, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35470566

RESUMO

A series of digermylenes R(EGeL)2 (L=CH[C(Me)N(Ar)]2 , Ar=2,6-iPr2 C6 H3 ; E=O, R=1,3-C6 H4 (1), 1,4-C6 H4 (2), Me2 C(CH2 )2 (3); E=NH, R=1,4-C6 H4 (4), 1,4-C6 H10 (5); E=C(O)O, R=1,3-C6 H4 (6)) were synthesized by the reactions of L'Ge (L'=HC[C(CH2 )N(Ar)]C(Me)N(Ar), Ar=2,6-iPr2 C6 H3 ) with selected diphenols, diol, diamines, and o-/m-phthalic acids, respectively. Treatment of digermylene 1,3-C6 H4 (OGeL)2 (1) with sulfur, selenium and CuX (X=Cl, Br, I) led to the formation of 1,3-C6 H4 [OGe(S)L]2 (8), 1,3-C6 H4 [OGe(Se)L]2 (9), and (CuX)2 [1,3-C6 H4 (OGeL)2 ]2 (X=Cl (10), Br (11), I (12)), respectively. The obtained products were characterized by melting point, elemental analysis, FT-IR, 1 H and 13 C NMR spectroscopy, and single-crystal X-ray diffraction.

12.
ACS Appl Mater Interfaces ; 14(49): 54539-54549, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36469497

RESUMO

An approach to differentially modify the internal surface of porous silicon nanoparticles (pSiNPs) with hydrophobic dodecene and the external surface with antifouling poly-N-(2-hydroxypropyl) acrylamide (polyHPAm) as well as a cell-targeting peptide was developed. Specifically, to generate these core-shell pSiNPs, the interior surface of a porous silicon (pSi) film was hydrosilylated with 1-dodecene, followed by ultrasonication to create pSiNPs. The new external surfaces were modified by silanization with a polymerization initiator, and surface-initiated atom transfer radical polymerization was performed to introduce polyHPAm brushes. Afterward, a fraction of the polymer side chain hydroxyl groups was activated to conjugate cRGDfK─a peptide with a high affinity and selectivity for the ανß3 integrin receptor that is overexpressed in prostate and melanoma cancers. Finally, camptothecin, a hydrophobic anti-cancer drug, was successfully loaded into the pores. This drug delivery system showed excellent colloidal stability in a cell culture medium, and the in vitro drug release kinetics could be fine-tuned by the combination of internal and external surface modifications. In vitro studies by confocal microscopy and flow cytometry revealed improved cellular association attributed to cRGDfK. Furthermore, the cell viability results showed that the drug-loaded and peptide-functionalized nanoparticles had enhanced cytotoxicity toward a C4-2B prostate carcinoma cell line in both 2D cell culture and a 3D spheroid model.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Humanos , Silício/química , Porosidade , Nanopartículas/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Linhagem Celular Tumoral
13.
Zhongguo Gu Shang ; 33(12): 1166-70, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33369326

RESUMO

OBJECTIVE: To evaluate the clinical outcome of tibiotalocalcaneal fusion using cannulated screw and humeral proximal locking plate inverted fixation through a lateral transfibular approach. METHODS: From June 2015 to December 2018, 15 patients underwent a tibiotalocalcaneal fusion operation using cannulated screw and inverted proximal humerus locking plate through a transfibular approach. There were 10 males and 5 females with the age ranging from 45 to 72 (58.9±6.1) years, and the course of disease ranged from 2 to 35 (11.9±7.9)years. Preoperative diagnosis included 8 cases of post traumatic arthritis, 2 cases of Charcot arthritis, 2 cases of Charcot-Marie -Tooth (CMT), 1 case of ankle tuberculosis, 1 case of talar necrosis, and 1 case of pigmented villonnodular synovitis. Among them, 8 patients were combined with simple varus deformity, 4 patients with simple valgus deformity, 2 patients with equinovarus deformity, 1 patient with equinovarus deformity, 2 patients with adduction and internal rotation of middle and forefoot. American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score and the visual analogue scale (VAS) score were used to evaluate the clinical outcome at the last follow up. RESULTS: One lost follow up and remaining fourteen patients were followed up. The follow up time ranged from 10 to 25(16.6±4.3) months. All the 15 patients had primary healing. Fusion time ranged from 15 to 24 (16.8 ± 2.4) weeks after operation. One patient with diabetes experienced delayed union and was successfully treated with secondary bone grafting combined with Platelet-Rich Plasma (PRP) injection. The AOFAS score increased from 38.7±3.3 to 84.5±2.6 (P<0.05), and the VAS score decreased from 7.5±1.6 to 1.9±0.3(P<0.05). CONCLUSION: Tibiotalocalcaneal fusion used cannulated screw and humeral proximal locking plate inverted fixation through a lateral transfibular approach has the advantages of relatively simple technique, high fusion rate, especially for patients with posterior foot deformity, which has satisfactory short term effects.


Assuntos
Placas Ósseas , Parafusos Ósseos , Articulação do Tornozelo , Artrodese , Feminino , Humanos , Úmero , Masculino , Estudos Retrospectivos , Resultado do Tratamento
14.
Nanomedicine (Lond) ; 14(24): 3213-3230, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31855121

RESUMO

Porous silicon (pSi) nanomaterials are increasingly attractive for biomedical applications due to their promising properties such as simple and feasible fabrication procedures, tunable morphology, versatile surface modification routes, biocompatibility and biodegradability. This review focuses on recent advances in surface modification of pSi for controlled drug delivery applications. A range of functionalization strategies and fabrication methods for pSi-polymer hybrids are summarized. Surface engineering solutions such as stimuli-responsive polymer grafting, stealth coatings and active targeting modifications are highlighted as examples to demonstrate what can be achieved. Finally, the current status of engineered pSi nanomaterials for in vivo applications is reviewed and future prospects and challenges in drug-delivery applications are discussed.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Polímeros/química , Silício/química , Porosidade
15.
Sci Rep ; 9(1): 1367, 2019 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718670

RESUMO

A new and facile approach to selectively functionalize the internal and external surfaces of porous silicon (pSi) for drug delivery applications is reported. To provide a surface that is suitable for sustained drug release of the hydrophobic cancer chemotherapy drug camptothecin (CPT), the internal surfaces of pSi films were first modified with 1-dodecene. To further modify the external surface of the pSi samples, an interlayer was applied by silanization with (3-aminopropyl)triethoxysilane (APTES) following air plasma treatment. In addition, copolymers of N-(2-hydroxypropyl) acrylamide (HPAm) and N-benzophenone acrylamide (BPAm) were grafted onto the external pSi surfaces by spin-coating and UV crosslinking. Each modification step was verified using attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, water contact angle (WCA) measurements, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). In order to confirm that the air plasma treatment and silanization step only occurred on the top surface of pSi samples, confocal microscopy was employed after fluorescein isothiocyanate (FITC) conjugation. Drug release studies carried out over 17 h in PBS demonstrated that the modified pSi reservoirs released CPT continuously, while showing excellent stability. Furthermore, protein adsorption and cell attachment studies demonstrated the ability of the graft polymer layer to reduce both significantly. In combination with the biocompatible pSi substrate material, the facile modification strategy described in this study provides access to new multifunctional drug delivery systems (DDS) for applications in cancer therapy.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Silício/química , Adsorção , Camptotecina/farmacologia , Adesão Celular , Contagem de Células , Liberação Controlada de Fármacos , Európio/química , Fibronectinas/química , Humanos , Cinética , Espectroscopia Fotoeletrônica , Porosidade , Albumina Sérica Humana/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
16.
Front Oncol ; 9: 369, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143705

RESUMO

Intrahepatic cholangiocarcinoma (ICC) ranks as the second most malignant type of primary liver cancer with a high degree of incidence and a very poor prognosis. Fat mass and obesity-associated protein (FTO) functions as an eraser of the RNA m6A modification, but its roles in ICC tumorigenesis and development remain unknown. We showed here that the protein level of FTO was downregulated in clinical ICC samples and cell lines and that FTO expression was inversely correlated with the expression of CA19-9 and micro-vessel density (MVD). A Kaplan-Meier survival analysis showed that a low expression of FTO predicted poor prognosis in ICC. in vitro, decreased endogenous expression of FTO obviously reduced apoptosis of ICC cells. Moreover, FTO suppressed the anchorage-independent growth and mobility of ICC cells. Through mining the database, FTO was found to regulate the integrin signaling pathway, inflammation signaling pathway, epidermal growth factor receptor (EGFR) signaling pathway, angiogenesis, and the pyrimidine metabolism pathway. RNA decay assay showed that oncogene TEAD2 mRNA stability was impaired by FTO. In addition, the overexpression of FTO suppressed tumor growth in vivo. In conclusion, our study demonstrated the critical roles of FTO in ICC.

17.
Artigo em Inglês | MEDLINE | ID: mdl-29234375

RESUMO

Kidney-replenishing herb is a traditional medicine formula in China which has been widely used for clinical treatment of recurrent miscarriage. Our previous study showed that Kidney-replenishing herb could promote proliferation and inhibit apoptosis of the human first-trimester trophoblasts. In the present study, we further explored the potential mechanism and signal pathway of Kidney-replenishing herb on human trophoblast cells. Our research showed that Kidney-replenishing herb stimulated proliferation and reduced apoptosis of human trophoblast cells in vitro, and this appeared to be positive correlation with SOCS-3 transcription, suggesting that Kidney-replenishing herb regulated biological functions of human trophoblast cells by inducing SCOS-3 expression. Furthermore, the Kidney-replenishing herb treatment stimulated the phosphorylation of ERK1/2, and blocking the signaling pathway by mitogen-activated protein MAPK (MEK) inhibitor, U0126, inhibited Kidney-replenishing herb-induced SOCS-3 transcription, depressed proliferation, and promoted apoptosis of human trophoblasts. Kidney-replenishing herbs still induced ERK1/2 phosphorylation after SOCS-3 siRNA silence. Overexpression of SOCS-3 stimulated the proliferation of trophoblast. These findings suggest that SOCS-3 expression is induced by Kidney-replenishing herbs via activation of MAPK pathways, and this may possibly be involved in promoting human trophoblast cells growth which is contributed to embryo development.

18.
Dalton Trans ; 45(12): 5223-8, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-26893036

RESUMO

A functional Cu(I) boron imidazolate framework (BIF) with a ladder-chain structure can not only change to another single-chain structure by incorporating 4,4'-bipyridine, but can also act as a reducing agent to load trimetal Au-Ag-Pd nanoparticles directly; the BIF with loaded noble NPs showed an excellent reduction effect on 4-nitrophenol. Moreover, we obtained a porous borocarbonitride by the direct carbonisation of this low-dimensional BIF. The resulting porous borocarbonitride exhibits fast adsorption behavior for 4-nitrophenol and can be a high-temperature conductor.

19.
Chempluschem ; 81(8): 724-727, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31968842

RESUMO

A novel isohedral 3-periodic net (i.e. a net with one kind of tile), showing a Cairo pentagonal tiling projection on the Euclidean plane, has been identified in a series of site-modified CuCN/CuSCN networks, namely, [Cu6 (SCN)2 (CN)6 ⋅Ni(tpy)2 ]n (1), [Cu6 (SCN)(CN)7 ⋅Ni(tpy)2 ]n (2) and [Cu6 (CN)8 ⋅Ni(tpy)2 ]n (3) (tpy=2,2':6'',2''-terpyridine). These infinite inclusion compounds were prepared via a solvothermal sulfur migration reaction with subtle modification to fine-tune the sulfur content. The chiroptical activity of single crystals, which arises from the intrinsically chiral net, was confirmed by X-ray diffraction and solid-state circular dichroism spectra.

20.
Dalton Trans ; 44(20): 9367-9, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25925416

RESUMO

A cubic cationic cage is rationally designed by using tridentate boron-imidazolate ligands to link tetrahedral metal Zn(ii) centers, which displays excellent properties in the Cr2O7(2-) exchange and can reduce Au(3+) ions into Au nanoparticles directly.

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