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1.
Heliyon ; 9(3): e14401, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36942220

RESUMO

In this work, a low-cost all-metal metamaterial near-field lens based on laser cutting technology is proposed. A novel spiral-slot structure is proposed to achieve miniaturized unit cells with an adjustable 360-degree phase shift at a length smaller than 0.2 times the operating wavelength. Since the unit is entirely constructed of stainless steel, it is resistant to high temperatures and high pressures compared to existing results. Moreover, a four-layer structure is used to increase the transmission coefficient. The final L-band near-field lens is constructed of 20 × 20 units. Simulation and measured results show that the half-power beamwidth of the focus is less than 211 mm from 1.52 GHz to 1.68 GHz at the focal spot observation plane of 500 mm from the lens. Since numerically controlled machine tools and three-dimensional printing are prohibitively expensive for machining large metal components, a low-cost all-metallic lens was manufactured using laser cutting technology. The measured results are in agreement with the simulation results.

2.
Biochem Biophys Res Commun ; 495(4): 2456-2461, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29287727

RESUMO

Bromodomains and extra-terminal (BET) proteins inhibitors are promising cancer therapeutic agents. However, tumor cells often develop resistance to BET inhibitors, greatly limiting their therapeutic potential. To study the mechanism underlying the resistance of BET inhibitors in hepatocellular carcinoma (HCC) cells, we herein investigated the impact of BET inhibitor JQ1 on the gene expression of Bcl-2 family members by RNA sequencing analysis, and found that acute treatment with JQ1 triggered upregulation of Mcl-1 in HCCLM3 and BEL7402 cell lines. This JQ1-triggered Mcl-1 upregulation was further confirmed by quantitative reverse transcription polymerase chain reaction and western blotting analysis, both at mRNA and protein levels. Inhibition of Mcl-1 by RNA interference dramatically enhanced JQ1-triggered caspase-3 activation, cleavage of poly (ADP-ribose) polymerase and apoptotic cell death induction in multiple HCC cell lines. Moreover, JQ1 in combination with cyclin-dependent kinase inhibitor flavopiridol at a subtoxic concentration that reduced expression of Mcl-1, triggered massive apoptotic cell death in HCCLM3 and BEL7402 cell lines. Together, these data suggest that Mcl-1 is a major contributor to BET inhibitor-resistance in HCC cells, and that combining drugs capable of down-regulating Mcl-1 may promote therapeutic potential in human HCC.


Assuntos
Apoptose/efeitos dos fármacos , Azepinas/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Triazóis/administração & dosagem , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Células Hep G2 , Humanos , Proteínas/antagonistas & inibidores , Regulação para Cima/efeitos dos fármacos
3.
Exp Ther Med ; 13(5): 2022-2028, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28565803

RESUMO

Chronic obstructive lesions of the subclavian artery (SCA) often result in subclavian steal syndrome, which leads to arm claudication, transient cerebral ischemia, and other serious complications. The lesions are classified as stenosis and occlusion, according to the degree of obstruction. Unlike totally occlusive lesions, including ostial occlusions, stenotic lesions have an excellent technical success rate. In the present study, ostial occlusions were classified into 4 types according to their angiographic appearance. A total of 8 patients (6 male, 2 female) with SCA occlusions were treated with percutaneous transluminal angioplasty and stenting over a 4-year period. Mean patient age was 65.6 years (range, 60-72 years). In total, 9 self-expanding and 1 balloon-expandable stent were implanted at the ostia of the SCA in 7 of the patients. One female patient did not undergo stenting. Bleeding at the access site was noted in 2 patients and was controlled by gauze pressure. The patient that did not undergo stenting was lost to follow-up with symptoms of a transient ischemic attack at 3 months. The mean follow-up time for the remaining 7 patients was 15.7 months (range, 1-36 months). No ischemic symptoms, neointimal hyperplasia, or restenosis was observed in these patients. The transfemoral artery operation approach is preferred for rat-tail and peak type occlusions, whereas the dual approach involving both femoral and radial arteries is preferred for hilly and plain type occlusions. The angiographic morphology typing used in the present study may serve as a reference to decide upon the interventional operation strategy to be used for improving the technical success rate.

4.
Oncotarget ; 8(63): 106833-106843, 2017 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-29290992

RESUMO

Bromodomain and Extra-Terminal Domain (BET) inhibitors, such as JQ1 have emerged as novel drug candidates and are being enthusiastically pursued in clinical trials for the treatment of cancer. However, many solid cancers are resistance to BET inhibitors. To explore methods for improving the therapeutic potential of BET inhibitors, we investigated the combinational activity of JQ1 with Oridonin, a bioactive molecules derived from Traditional Chinese Medicine in hepatocellular carcinoma (HCC) cells. Our results showed that Oridonin synergistically enhanced the abilities of JQ1 to inhibit cell viability in HCC cells and, significantly augmented JQ1-triggered apoptosis in HCC cells and in HCC cancer stem-like cells. Moreover, Oridonin dose-dependently inhibited the expression of several anti-apoptotic proteins, such as Bcl-2, Mcl-1, and x-linked inhibitor of apoptosis (xIAP) in HCC cells. Cell fractionation and western blotting analysis showed that the enhancement of apoptosis by Oridonin was associated with cytochrome c release, activation of caspase-9, -3 and cleavage of PARP, indicating the activation of mitochondrial apoptosis pathway. Altogether, our findings demonstrate that Oridonin may be used to effectively enhance the sensitivity of BET inhibitors in HCC therapy via downregulation of the expression of multiple anti-apoptotic proteins.

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