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1.
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.

2.
Biochem Biophys Res Commun ; 516(3): 983-990, 2019 Aug 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.

3.
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.

4.
Sci Rep ; 9(1): 1367, 2019 Feb 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.

5.
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.

6.
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.

7.
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.

8.
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.

9.
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.

10.
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.

11.
Chem Commun (Camb) ; 51(7): 1353-5, 2015 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-25486112

RESUMO

A Cu(I) boron imidazolate framework with 2-fold interpenetrating ths topology shows luminescent mechanochromism, and it can directly reduce bimetal Au-Ag nanoparticles into its structure, leading to catalytic applications.

12.
Chem Commun (Camb) ; 50(63): 8754-6, 2014 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-24967572

RESUMO

A redox-active Cu(I) boron imidazolate framework with ladder-chain structure shows mechanochromic luminescence and can directly reduce Ag nanoparticles into its structure, due to the presence of rich B-H functional bonds in the structure.

13.
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
14.
Chem Commun (Camb) ; 49(50): 5660-2, 2013 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-23677170

RESUMO

A multifunctional Cu(I) coordination polymer constructed from helical chains showed unusual mechanochromic, sensing of nitrobenzene and photocatalytic properties on degradation of organic dyes.

15.
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
16.
Exp Ther Med ; 3(3): 423-432, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22969906

RESUMO

The identification of prognostic factors for pancreatic cancer patients could provide insightful information for their management in the clinic. A total of 302 pancreatic cancer patients were enrolled in this study. The clinicopathological characteristics, treatment selection and laboratory test data were retrospectively retrieved from the medical records and follow-up data were obtained via telephone interview. Cox survival analysis was used to assess the potential prognostic factors, and survival curves were obtained by Kaplan-Meier analyses. The mortality rate of the patients was 83.4% (252/302) and the median survival of these patients was 6.1 months, with 1-, 2- and 3-year survival rates of 30.1 (91/302), 10.6 (32/302) and 2.6% (8/302), respectively. The most influential factors for the survival of these patients were the site of primary cancer, tumor stage, treatment selection, serum levels of glutamic-pyruvic transaminase, albumin, lactate dehydrogenase and hemoglobin, and white blood cell counts (P<0.05). The median survival of patients who did not receive any treatment or just received supportive treatment was 1.3 months, while the median overall survival of patients who underwent surgery, chemotherapy, biliary drainage therapy, arterial interventional chemotherapy and comprehensive treatment was 11.0, 7.3, 3.5, 9.0 and 11.0 months, respectively (P<0.05). Furthermore, single-drug chemotherapy was not statistically associated with patient survival in those who received the multi-drug regimen (P>0.05). However, the mortality risk of patients who received platinum chemotherapy was decreased [hazard ratio (HR)=0.56, 95% CI 0.35-0.88, P=0.011] compared to the patients who did not receive this treatment (P<0.05). Tumor stage, treatment selection, serum albumin levels, urea nitrogen, CA19-9, white blood cell and platelet counts were independent prognostic factors for the prediction of survival in pancreatic cancer. Future studies are required in order to verify these data. Chemotherapy with platinum regimens could improve overall survival in patients with pancreatic cancer.

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