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1.
Biotechnol Appl Biochem ; 71(2): 256-263, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38053502

RESUMO

Osteoporosis is with porous bones, which refers to a decrease in the bone mineral density and weakens the bones to become brittle. Osteoporosis often progresses without any pain or symptoms until the bone fractures. Monitoring the condition of bone regularly helps to identify the bone that weakens at its earlier stages. In general, radiological techniques have been used to measure bone mineral density, are expensive, and the procedures are complicated. Therefore, researchers are focusing on the alternative method of biomarker quantification to identify bone mineral density. This research work was focused on quantifying the osteoporosis biomarker of C-terminal telopeptide of type I collagen (CTX-I) on an interdigitated electrode (IDE) sensor. Gold nanomaterial-modified anti-CTX-I antibody was attached to silica nanomaterial-decorated IDE and then identified by CTX-I interaction. Higher immobilization of antibodies was recorded on diamond-modified IDE through gold nanoparticles, and detected CTX-I as low as 0.5 pg/mL [y = 1.5507x - 0.9043 R2 = 0.9715], determined on a linear curve at the range 0.5-3.5 ng/mL. Further, specific identification of CTX-I was confirmed by control performances with osteopontin, IL-6, and anti-IgG antibody.


Assuntos
Nanopartículas Metálicas , Osteoporose , Humanos , Ouro , Peptídeos , Osteoporose/diagnóstico , Imunoensaio , Eletrodos , Biomarcadores
2.
Small ; 19(2): e2205257, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36344428

RESUMO

Nickel based materials are promising electrocatalysts to produce hydrogen from water in alkaline media. However, the stability is of great challenge, limiting its practical material functions. Herein, a new technique for electro-deposition flower-like NiCo2 S4 nanosheets on carbon-cloth (CC@NiCo2 S4 ) is proposed for energy-saving production of H2 from water/methanol coelectrolysis at high current density by constructing array architectures and regulating surface magnetism. The optimized and fine-tuned magnetism on the surface of the electrochemical in situ grown CC@NiCo2 S4 nanosheet array result in (0 1 -1) surface universally exposed, high catalytic activity for methanol electrooxidation, and long-term stability at high current density. X-ray photoelectron spectroscopy in combination of density functional theory calculations confirm the valence electron states and spin of d electrons for the surface of NiCo2 S4 , which enhance the surface stability of catalysts. This technology may be utilized to alter the surface magnetism and increase the stability of Ni-based electrocatalytic materials in general.

3.
Cancer Sci ; 113(4): 1362-1376, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35150045

RESUMO

Tumor metastasis is a series of complicated biological events. Hematogenous metastasis mediated by von Willebrand factor (vWF) is critical in tumor metastasis. However, the source of vWF and its role in tumor metastasis are controversial, and the further mechanism involved in mediating tumor metastasis is still unclear. In this study, we first demonstrated that lung adenocarcinoma cells could express vWF de novo and promotes tumor metastasis. Through the analysis of transcriptome sequencing, the metastasis promotion effect of vWF may be related to phosphorylase kinase subunit G1 (PHKG1), a catalytic subtype of phosphorylase kinase (PhK). PHKG1 was highly expressed in lung adenocarcinoma patients and led to poor prognosis. Further experiments found that lung adenocarcinoma-derived vWF induced the upregulation of PHKG1 through the PI3K/AKT pathway to promote glycogenolysis. Glycogen was funneled into glycolysis, leading to increased metastasis. Tumor metastasis assayed in vitro and in vivo showed that knockdown of PHKG1 or synergistic injection of phosphorylase inhibition based on the overexpression of vWF could inhibit metastasis. In summary, our research proved that lung adenocarcinoma-derived vWF may mediate tumor metastasis by regulating PHKG1 to promote glycogen metabolism and suggested potential targets for inhibition of lung adenocarcinoma metastasis.


Assuntos
Adenocarcinoma de Pulmão , Glicogenólise , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Glicogênio/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilase Quinase/metabolismo , Fator de von Willebrand/metabolismo
4.
Small ; 18(40): e2204100, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35996763

RESUMO

Pt-Co electrocatalysts have attracted significant attention because of their excellent performance in many electrochemical reactions. This review focuses on Pt-Co electrocatalysts designed and prepared for electrocatalytic applications. First, the various synthetic methods and synthesis mechanisms are systematically summarized; typical examples and core synthesis parameters are discussed for regulating the morphology and structure. Then, starting with the design and structure-activity relationship of catalysts, the research progress of the morphologies and structures of Pt-Co electrocatalysts obtained based on various strategies, the structure-activity relationship between them, and their properties are summarized. In addition, the important electrocatalytic applications and mechanisms of Pt-Co catalysts, including electrocatalytic oxidation/reduction and bifunctional catalytic reactions, are described and summarized, and their high catalytic activities are discussed on the basis of their mechanism and active sites. Moreover, the advanced electrochemical in situ characterization techniques are summarized, and the challenges and direction concerning the development of high-performance Pt-Co catalysts in electrocatalysis are discussed.


Assuntos
Técnicas Eletroquímicas , Catálise , Técnicas Eletroquímicas/métodos , Oxirredução
5.
Toxicol Appl Pharmacol ; 440: 115927, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35192807

RESUMO

The metastasis and angiogenesis of breast cancer has always been a difficult problem for treatment. It has recently been discovered that Von Willebrand Factor (vWF), in addition to hemostasis, also plays a role in tumor metastasis and angiogenesis. We noticed that besides endothelial cells, breast cancer cells (MDA-MB-231 and MCF-7) could also express vWF. In vitro experiments showed that knocking down vWF inhibited breast cancer cell metastasis. And we found that overexpression of vWF significantly promoted VEGF-A-dependent vascular proliferation in vitro by activating the PI3K/Akt signaling pathway. Further studies indicated that inhibition of PI3K/Akt signaling pathway up-regulated the expression of miR-205-5p, and miR-205-5p could bind to the 3'UTR region of VEGF-A to hinder the production of VEGF-A. Furthermore, when a spontaneous lung metastasis model was established in Balb/c female mice, knockdown of vWF in 4 T1 cells resulted in a decrease in tumor blood vessel density and effectively inhibited lung metastasis, accompanied by a decrease in the expression level of VEGF-A and an increase in the expression level of miR-205-5p. In summary, our findings provide experimental evidence that overexpression of vWF in breast cancer cells down-regulates the expression of miR-205-5p and up-regulates the expression of VEGF-A through the PI3K/Akt signaling pathway, thereby promoting tumor angiogenesis and metastasis.


Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , MicroRNAs , Fator de von Willebrand , Animais , Neoplasias da Mama/patologia , Proliferação de Células , Células Endoteliais/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , MicroRNAs/metabolismo , Neovascularização Patológica/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/metabolismo
6.
Toxicol Appl Pharmacol ; 438: 115911, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35143806

RESUMO

The therapeutic efficacy of tyrosine kinase inhibitors (TKIs) on solid tumors is limited by drug resistance and side effects. Currently, the combination therapy comprises of TKIs and angiogenesis inhibitors have been corroborated as an effective approach in cancer therapy. Ethoxy-erianin phosphate (EBTP) is an anti-angiogenic compound with low toxicity obtained by structural modification of the natural product erianin. Here, we aimed to evaluate whether EBTP can cooperate with TKIs to inhibit the proliferation and angiogenesis of tumor cells and reduce toxic effects. First, CCK-8 results showed that EBTP can effectively inhibit the proliferation of liver cancer cell line HepG2. We combined EBTP with four TKIs (Bosutinib, Apatinib, Afatinib and Erlotinib) to treat HepG2 cells and CompuSyn software analysis suggested that EBTP/Afatinib(Afa)shows the best synergistic inhibitory effect. Meanwhile, EBTP/Afa can significantly suppress the proliferation, invasion, migration and angiogenesis of HepG2 and HUVECs. ELISA results revealed that EBTP/Afa inhibits the secretion of VEGF in HepG2. EBTP/Afa down-regulates the expression of VEGF, p-VEGFR1, p-VEGFR2 and p-EGFR in both HepG2 and HUVECs. Further, the supernatant of HepG2 cells treated with EBTP/Afa blocks the intracellular downstream signal transduction shared by VEGF and EGFR in HUVECs. Finally, EBTP/Afa significantly inhibits tumor growth and angiogenesis in vivo. To conclude, EBTP/Afa targets VEGF and EGFR signaling pathways in liver cancer cells and tumor vasculature, thereby inhibiting the proliferation, motion and angiogenesis of liver cancer cells. Overall, this study provides a new combined strategy for the clinical treatment of hepatocellular carcinoma.


Assuntos
Afatinib/farmacologia , Bibenzilas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fenol/farmacologia , Fosfatos/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Células HCT116 , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neovascularização Patológica/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Phys Chem Chem Phys ; 24(30): 18083-18093, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35876809

RESUMO

Cesium (Cs+) and strontium (Sr2+) ions are the main fission byproducts in the reprocessing of spent nuclear fuels for nuclear power plants. Their long half-live period (30.17 years for 137Cs and 28.80 years for 90Sr) makes them very dangerous radionuclides. Hence the solidification of Cs+ and Sr2+ is of paramount importance for preventing them from entering the human food chain through water. Despite tremendous efforts for solidification, the long-term stability remains a great challenge due to the experimental limitation and lack of good evaluation indicators for such long half-life radionuclides. Using density functional theory (DFT), we investigate the origin of long-term stability for the solidification of Cs+ and Sr2+ inside sodalite and establish that the exchange energy and the diffusion barrier play an important role in gaining the long-term stability both thermodynamically and kinetically. The acidity/basicity, solvation, temperature, and diffusion effect are comprehensively studied. It is found that solidification of Cs+ and Sr2+ is mainly attributed to the solvation effect, zeolitic adsorption ability, and diffusion barriers. The present study provides theoretical evidence to use geopolymers to adsorb Cs+ and Sr2+ and convert the adsorbed geopolymers to zeolites to achieve solidification of Cs+ and Sr2+ with long-term stability.


Assuntos
Césio , Zeolitas , Adsorção , Difusão , Humanos , Estrôncio
8.
Environ Toxicol ; 37(2): 349-361, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34741589

RESUMO

Ionizing radiation (IR) brings many health problems to humans, causing damage to the digestive system, hematopoietic system, and immune system. Natural compounds derived from plants have attracted widespread attention due to their low toxicity. Here, we found that 3,4,5-O-tricaffeoylquinic acid (tCQA) extracted from natural plant Azolla imbricata could significantly alleviate the systemic damage in mice caused by IR. In order to further explore the molecular mechanism of the radioprotective effect of tCQA, in vitro experiments confirmed that tCQA could attenuate the cytotoxic effect of IR on the colonic epithelial cell line NCM460 and alleviate the IR-induced mitochondrial dysfunction characterized by the decrease of mitochondrial transmembrane potential, ROS production, and caspase-dependent apoptosis. In addition, the generation of ROS induced by H2 O2 could also be reversed by tCQA. Then, Western blot demonstrated that tCQA could reverse the MAPK signaling pathway activated by IR. However, the inhibitory effect of tCQA on JNK and P38 levels activated by the JNK agonist anisomycin is not obvious; meanwhile, tCQA could inhibit the activation of JNK/P38 induced by H2 O2 , which suggests that tCQA might inhibit the JNK/P38 signaling pathway by reducing ROS. In short, tCQA inhibits the generation of ROS caused by IR, and then regulates the activity of caspase in the mitochondrial pathway by inhibiting the JNK/P38 signaling pathway, thereby alleviating the apoptosis of NCM460. This research provides an experimental basis for the development of new types of radioprotective agents for medical diagnosis and radiotherapy.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Apoptose , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Potencial da Membrana Mitocondrial , Camundongos , Radiação Ionizante , Espécies Reativas de Oxigênio , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
9.
J Cell Physiol ; 236(4): 3114-3128, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33078417

RESUMO

In cancer treatment, the most attractive feature of mesenchymal stem cells (MSCs) is it's homing to tumor tissues. MSC is an important part of the "colon cancer stem cell niche", but little research has been done on the tropism of human MSCs toward colon cancer stem cells (CCSCs). In this study, we first compared the effects of three tissue-derived MSCs (bone marrow, adipose tissue, and placenta) in vivo on colon tumor xenograft growth. Then, we analyzed the tropism of bone marrow-derived MSCs (BMSCs) toward normal intestinal epithelial cells (NCM460), parental colon cancer cells, CD133- /CD44-, and CD133+ /CD44+ colon cancer cells in vitro. Microarray analysis and in vitro experiments explored the mechanism of mediating the homing of BMSCs toward CCSCs. Compared with the parental and CD133- /CD44- colon cancer cells, CD133+ /CD44+ cells have a stronger ability to recruit BMSCs. In addition, BMSCs were significantly transformed into cancer-associated fibroblasts after being recruited by CCSCs. After coculture of BMSCs and CCSCs, the expression of interleukin (IL)-6, IL-8, IL-32, and CCL20 was significantly increased. Compared with parental strains, CD133- /CD44- cells, and NCM460, BMSC secreted significantly more IL-8 after coculture with CD133+ /CD44+ cells. Low concentration of IL-8 peptide inhibitors (100 ng/ml) and CXC receptor 2 (CXCR2) inhibitors have little effect on the migration of BMSCs, but can effectively weaken CCSC stemness and promote dormant CSCs in the coculture system to re-enter into the cell cycle. The endogenous IL-8 knockout in BMSCs or BMSCs loaded with IL-8 and/or CXCR2 inhibitors will make the therapy of BMSC targeting CCSCs function at its best.


Assuntos
Antígeno AC133/metabolismo , Neoplasias do Colo/patologia , Receptores de Hialuronatos/metabolismo , Interleucina-8/metabolismo , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Neoplásicas/patologia , Tropismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Autorrenovação Celular , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Biochem Biophys Res Commun ; 552: 183-190, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33751936

RESUMO

Malignant melanoma is a critical and aggressive skin tumor with a steeply rising incidence and a less favorable prognosis due to the lack of efficient treatment. Photodynamic therapy (PDT) is a new promising treatment for this tumor through photosensitizers-mediated oxidative cytotoxicity. In this study, we explored the role of berberine-mediated PDT (BBR-PDT) in the anti-proliferative effect on human malignant melanoma cells (MMCs). We found that there were significant differences between MMCs with BBR-PDT and MMCs with BBR or PDT only. Further research showed that BBR-PDT induced apoptosis via up-regulating the expression of cleaved caspase-3 protein. We also observed that LC3-related autophagy level was upregulated in MMCs with BBR-PDT. Besides, it was also found that BBR-PDT activated endoplasmic reticulum (ER) stress, involving a dramatic increase in reactive oxygen species (ROS). Interestingly, the knockdown of CHOP protein expression inhibited apoptosis, autophagy and ER stress levels caused by BBR-PDT, suggesting that CHOP protein may be related to apoptosis, autophagy and ER stress in MMCs with BBR-PDT. Collectively, our results indicated that BBR-PDT had an essential impact on MMCs' growth inhibition, and therefore may reveal the possibility of developing BBR-PDT into human malignant melanoma.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Berberina/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Melanoma/terapia , Fotoquimioterapia/métodos , Fator de Transcrição CHOP/metabolismo , Apoptose/efeitos da radiação , Autofagia/efeitos da radiação , Berberina/química , Western Blotting , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos da radiação , Humanos , Luz , Melanoma/metabolismo , Melanoma/patologia , Estrutura Molecular , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação
11.
Toxicol Appl Pharmacol ; 418: 115484, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33716044

RESUMO

The clinical use of cisplatin are limited due to its drug resistance. Thus, it is urgent to find effective combination therapy that sensitizes tumor cells to this drug. The combined chemo-photodynamic therapy could increase anti-tumor efficacy while also reduce the side effects of cisplatin. Berberine is an isoquinoline alkaloid, which has been reported to show high photosensitizing activity. In this study, we have examined the effect of a combination of cisplatin and berberine-PDT in cisplatin-resistant melanoma cells. The cytotoxic effects of berberine-PDT alone or in combination with cisplatin were tested by MTT assays. We then examined the subcellular localization of berberine with confocal fluorescence microscopy. The percentage of apoptotic cells, the mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) generation assessed using flow cytometry analysis. Western blotting used in this study to determine the expression levels of MAPK signaling pathways and apoptosis-related proteins. Experimental data revealed that the mode of cell death is the caspase-dependent mitochondrial apoptotic pathways. Excessive accumulation of ROS played a key role in this process, which is confirmed by alleviation of cytotoxicity upon pretreatment with NAC. Furthermore, we found that the combined treatment activated MAPK signaling pathway. The inhibition of p38 MAPK by pretreating with SB203580 block the combined treatment-induced apoptotic cell death. In conclusion, berberine-PDT could be used as a chemo-sensitizer by promoting cell death through activation of a ROS/p38/caspase cascade.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Berberina/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/tratamento farmacológico , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Melanoma/enzimologia , Melanoma/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Transdução de Sinais , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia
12.
Cell Biol Int ; 45(12): 2420-2428, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34351659

RESUMO

Multidrug resistance (MDR) is the main cause of chemotherapy failure in the treatment of colon cancer and the high expression of drug efflux protein P-gp is one of the main factors of MDR. P-gp expression is regulated by the signal transducer and activator of transcription 3 (STAT3) signaling pathway. In this study, human colon cancer oxaliplatin-resistant cells were treated with oxaliplatin combined with the natural product erianin. Then, we evaluated the impact of erianin on drug resistance, and explored the relationship between erianin-related oxaliplatin resistance and the Janus kinase 2/STAT3 signaling pathway in vitro. Our research showed that erianin could significantly inhibit the proliferation of human colon cancer oxaliplatin-resistant cells, and suppress the cell cycle of oxaliplatin-resistant cells in the G2/M phase, indicating that erianin could regulate the MDR phenotype of oxaliplatin-resistant cells, and its mechanism might be the inhibition of STAT3 signaling pathway and the significant reduction of P-gp expression. However, this study provides a theoretical basis for the clinical application of erianin in platinum-based chemotherapy for colon cancer.


Assuntos
Bibenzilas/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Oxaliplatina/farmacologia , Fenol/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HCT116 , Humanos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Bioorg Med Chem Lett ; 51: 128371, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534673

RESUMO

Malignant gliomas are the most common brain tumors, with generally dismal prognosis, early clinical deterioration and high mortality. Recently, 2-aminoquinoline scaffold derivatives have shown pronounced activity in central nervous system disorders. We herein reported a series of 2-aminoquinoline-3-carboxamides as novel non-alkylator anti-glioblastoma agents. The synthesized compounds showed comparable activity to cisplatin against glioblastoma cell line U87 MG in vitro. Among them, we found that 6a displayed good inhibitory activity against A172 and U118 MG glioblastoma cell lines and induced cell cycle arrest in the G2/M phase and apoptosis in U87 MG by flow cytometry analysis. Additionally, 6a displayed low cytotoxicity to several normal human cell lines. In silico study showed 6a had promising physicochemical properties and was predicted to cross the blood-brain barrier. Moreover, preliminary structure-activity relationships are also investigated, shedding light on further modifications towards more potent agents on this series of compounds. Our results suggest this compound has a promising potential as an anti-glioblastoma agent with a differential effect between tumor and non-malignant cells.


Assuntos
Aminoquinolinas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Desenho de Fármacos , Glioblastoma/tratamento farmacológico , Aminoquinolinas/síntese química , Aminoquinolinas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Modelos Moleculares , Estrutura Molecular , Relação Estrutura-Atividade
14.
Bioorg Chem ; 107: 104515, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33272708

RESUMO

Nineteen indole alkaloids including eleven new ones, taberdines A-K (1-11), were isolated from Tabernaemontana divaricata. Their structures were assigned by MS, NMR, single crystal X-ray diffractions, and ECD analyses. Alkaloid 1 is an aspidosperma-type monoterpenoid indole alkaloid and possesses a rearranged pyrrolidine moiety due to C-3 degradation, and 4 has a rare 1,3-oxazolidine moiety within iboga-type alkaloids. Alkaloids 2, 4, 6, and 11-19 combined with 5 µg/mL fluconazole exhibited significant activity to reverse fluconazole resistance in Candida albicans strains while no one used alone showed any activities against the resistant strain.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Alcaloides Indólicos/farmacologia , Tabernaemontana/química , Testes de Sensibilidade Microbiana , Folhas de Planta/química
15.
Small ; 16(10): e1907341, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32049440

RESUMO

Different from graphene with the highly stable sp2 -hybridized carbon atoms, which shows poor controllability for constructing strong interactions between graphene and guest metal, graphdiyne has a great potential to be engineered because its high-reactive acetylene linkages can effectively chelate metal atoms. Herein, a hydrogen-substituted graphdiyne (HsGDY) supported metal catalyst system through in situ growth of Cu3 Pd nanoalloys on HsGDY surface is developed. Benefiting from the strong metal-chelating ability of acetylenic linkages, Cu3 Pd nanoalloys are intimately anchored on HsGDY surface that accordingly creates a strong interaction. The optimal HsGDY-supported Cu3 Pd catalyst (HsGDY/Cu3 Pd-750) exhibits outstanding electrocatalytic activity for the oxygen reduction reaction (ORR) with an admirable half-wave potential (0.870 V), an impressive kinetic current density at 0.75 V (57.7 mA cm-2 ) and long-term stability, far outperforming those of the state-of-the-art Pt/C catalyst (0.859 V and 15.8 mA cm-2 ). This excellent performance is further highlighted by the Zn-air battery using HsGDY/Cu3 Pd-750 as cathode. Density function theory calculations show that such electrocatalytic performance is attributed to the strong interaction between Cu3 Pd and CC bonds of HsGDY, which causes the asymmetric electron distribution on two carbon atoms of CC bond and the strong charge transfer to weaken the shoulder-to-shoulder π conjugation, eventually facilitating the ORR process.

16.
Org Biomol Chem ; 18(39): 7932-7935, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33001123

RESUMO

Ulvan is a sulfated polysaccharide from green algae with potent antitumor, antiviral, and immunomodulatory activities. However, no chemical synthesis of ulvan saccharides has been reported to date. In this paper, we performed the first efficient synthesis of the unique sulfated tetrasaccharide motif of type B ulvanobiuronic acid 3-sulfate. Based on the gold(i)-catalyzed glycosylation with glycosyl ynenoates as donors, efficient construction of the challenging α-(1 → 4)-glycosidic bonds between iduronic acid and rhamnose building blocks was achieved to afford the tetrasaccharide skeleton in a stereospecific manner. The synthetic sulfated tetrasaccharide was found to significantly improve the phagocytic activity of macrophage RAW264.7 cells.


Assuntos
Sulfatos
17.
BMC Musculoskelet Disord ; 21(1): 340, 2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32487055

RESUMO

BACKGROUND: Multiple surgical procedures are applied in young patients with symptomatic lumbar spondylolysis when conservative treatments fail. Although the optimal surgical procedure option is controversial, the treatment paradigm has shifted from open surgery to minimally invasive spine surgery. To date, a limited number of studies on the feasibility of percutaneous endoscopic-assisted direct repair of pars defect have been carried out. Herein, for the first time, we retrospectively explore the outcomes of pars defect via percutaneous endoscopy. METHODS: We retrospectively examined young patients with spondylolysis treated using the percutaneous endoscopic-assisted direct repair of pars defect supplemented with autograft as well as percutaneous pedicle screw fixation between September 2014 and December 2018. Six patients with a mean age of 18.8 years were enrolled in the study. We used preoperatively computed tomographic (CT) scans to evaluate the size of pars defect, and graded disc degeneration using Pfirrmann's classification through magnetic resonance images (MRI). We assessed the clinical outcomes using the Oswestry Disability Index (ODI), 36-Item Short-Form Health Survey (SF-36) as well as Visual Analogue Scale for back pain (VAS-B). RESULTS: Our findings revealed that pain intensity and function outcomes, including VAS-B, ODI, and SF-36 (PCS and MCS) scores, were markedly improved after surgery and at the final follow-up visit. The change in the gap distance of the pars defect was remarkably significant after surgery and during the follow-up period. Only one of the 12 pars repaired was reported as a non-union at the final follow-up visit. Moreover, no surgery-related complications were reported in any of the cases. CONCLUSION: Percutaneous endoscopic-assisted direct repair of pars defect without general anesthesia, a minimally invasive treatment option, supplemented with autograft and percutaneous pedicle screw fixation, could be a satisfying treatment alternative for young patients with symptomatic lumbar spondylolysis.


Assuntos
Endoscopia/métodos , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fusão Vertebral/métodos , Espondilólise/cirurgia , Adolescente , Parafusos Ósseos , Transplante Ósseo , Endoscopia/instrumentação , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Medição da Dor , Estudos Retrospectivos , Fusão Vertebral/instrumentação , Espondilólise/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Transplante Autólogo , Resultado do Tratamento , Adulto Jovem
18.
BMC Surg ; 20(1): 233, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046007

RESUMO

BACKGROUND: For ventral hernia, endoscopic sublay repair (ESR) may overcome the disadvantages of open sublay and laparoscopic intraperitoneal onlay mesh repair. This retrospective study presents the preliminary multicenter results of ESR from China. The feasibility, safety, and effectiveness of ESR were evaluated; its surgical points and indications were summarized. METHODS: The study reviewed 156 ventral hernia patients planned to perform with ESR in ten hospitals between March 2016 and July 2019. Patient demographics, hernia characteristics, operative variables, and surgical results were recorded and analyzed. RESULTS: ESR was performed successfully in 153 patients, 135 with totally extraperitoneal sublay (TES) and 18 with transabdominal sublay (TAS). In 19 patients, TES was performed with the total visceral sac separation (TVS) technique, in which the space separation is carried out along the peritoneum, avoiding damage to the aponeurotic structure. Endoscopic transversus abdominis release (eTAR) was required in 17.0% of patients, and only 18.3% of patients required permanent mesh fixation. The median operative time was 135 min. Most patients had mild pain and resume eating soon after operation. No severe intraoperative complications occurred. Bleeding in the extraperitoneal space occurred in two patients and was stopped by nonsurgical treatment. Seroma and chronic pain were observed in 5.23 and 3.07% of patients. One recurrence occurred after TAS repair for an umbilical hernia. CONCLUSION: ESR is feasible, safe, and effective for treating ventral hernias when surgeons get the relevant surgical skills, such as the technique of "partition breaking," TVS, and eTAR. Small-to-medium ventral hernias are the major indications.


Assuntos
Hérnia Ventral , Herniorrafia , Laparoscopia , Idoso , China , Feminino , Hérnia Ventral/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Telas Cirúrgicas
19.
J Cell Physiol ; 234(12): 22703-22718, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31120140

RESUMO

Colon cancer stem cells (CCSCs) stand for a critical subpopulation of colon cancer cells that possess self-renewal and multilineage differentiation potentials and drive tumorigenicity. Due to their impact on treatment tolerance, CCSCs have been a hot research topic in the past few years. We have previously reported that miR-139-5p is a vital tumor repressive noncoding RNA whose level decreases in the clinical colon cancer samples with the increase of tumor malignancy. This research discovered that miR-139-5p targets the Wnt/ß-catenin/TCF7L2 downstream effector E2-2 in CCSCs. E2-2 is a pivot molecule in the negative feedback loop of miR-139-5p/Wnt/ß-catenin/TCF7L2. Its small interfering RNA reverses the stemness maintenance and epithelial-mesenchymal transition of colon cancer CSCs. This study provides a theoretical foundation for the clinical diagnosis and medical treatment of recurrent or metastatic colon cancer with miR-139-5p and its target E2-2.


Assuntos
Movimento Celular , Neoplasias do Colo/metabolismo , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Antígeno AC133/metabolismo , Animais , Autorrenovação Celular , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HT29 , Humanos , Receptores de Hialuronatos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Fenótipo , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Via de Sinalização Wnt
20.
J Cell Biochem ; 120(10): 16978-16989, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31111562

RESUMO

The effects of ethoxy-erianin phosphate (EBTP) on cell proliferation, mitotic cell arrest, migration, infiltration, and endothelial tubular structures were evaluated in this study. The antiproliferative activity of EBTP and combretastatin A-4P (CA4P) was analyzed on several tumor cells (including MCF-7, HeLa, 2LL, and 2LL-IDO) and on an endothelial cell (human umbilical vein endothelial cells [HUVECs]) as well as a human normal liver cell (L02). The results showed that EBTP possessed antiproliferative activity in the micromole range and was relatively less toxic than CA4P. Treating HUVECs with EBTP caused cell accumulation in the G2/M phase, and wound-healing assays indicated that EBTP inhibited cell migration. Furthermore, EBTP and CA4P destroyed the vasculature in endothelial cells and showed vascular disrupting activity of the chorioallantoic membrane in fertilized chicken eggs. In addition, we found that EBTP suppressed the expression of indoleamine 2,3-dioxygenase (IDO) and significantly inhibited IDO-induced migration and infiltration of 2LL-IDO cells. Administration of EBTP blocked vasculogenic mimicry in 2LL-IDO cells, which was typically observed in tube formation assays of 2LL-IDO cells. Moreover, the results of Lewis lung carcinoma in mice showed a high inhibition rate of EBTP. EBTP is an effective vascular disrupting agent that is superior to CA4P and may prevent and treat malignancy by inhibiting the expression of IDO.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Bibenzilas/farmacologia , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Neovascularização Patológica/tratamento farmacológico , Animais , Carcinoma Pulmonar de Lewis/enzimologia , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Células HeLa , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Pulmão/patologia , Células MCF-7 , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/enzimologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Estilbenos/farmacologia , Carga Tumoral/efeitos dos fármacos
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