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1.
Int Immunopharmacol ; 124(Pt A): 110907, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37683397

RESUMO

Minimal deviation adenocarcinoma (MDA) of the uterine cervix, also referred to as malignant adenoma, is a rare subtype of cervical adenocarcinoma that exhibits histological characteristics resembling those of benign tumors, resulting in a low diagnostic rate and a lack of effective treatment options. The transcriptomic features of MDA at the single-cell resolution and within the tumor microenvironment (TME) remain unclear. In this study, we conducted single-cell transcriptomic analyses of MDA samples (Ca) and adjacent normal tissues (PCa). The present study reveals the prevalence of dendritic cells (DCs) and T cells in the carcinoma (Ca) of mammary ductal adenocarcinoma (MDA), with DCs undergoing significant metabolic reprogramming and immune stress. Additionally, our findings demonstrate the crucial involvement of DCs and T cells in the pathogenesis and metastatic progression of MDA, as evidenced by single-cell transcriptomic profiling of MDA and HPV samples. This resource provides a more profound understanding of the indolent nature of MDA and may prove useful in the development of MDA immunotherapy.

2.
Nat Commun ; 13(1): 7680, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36509764

RESUMO

Quasi-periodic pulsations (QPPs) are frequently detected in solar and stellar flares, but the underlying physical mechanisms are still to be ascertained. Here, we show microwave QPPs during a solar flare originating from quasi-periodic magnetic reconnection at the flare current sheet. They appear as two vertically detached but closely related sources with the brighter ones located at flare loops and the weaker ones along the stretched current sheet. Although the brightness temperatures of the two microwave sources differ greatly, they vary in phase with periods of about 10-20 s and 30-60 s. The gyrosynchrotron-dominated microwave spectra also present a quasi-periodic soft-hard-soft evolution. These results suggest that relevant high-energy electrons are accelerated by quasi-periodic reconnection, likely arising from the modulation of magnetic islands within the current sheet as validated by a 2.5-dimensional magnetohydrodynamic simulation.

3.
R Soc Open Sci ; 8(8): 202285, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34457329

RESUMO

The development of high-performance air filter has become more and more important to public health. However, it has always been very challenging for developing a multifunctional air filter to simultaneously achieve excellent filtration and antibacterial properties. Herein, a versatile air filter was prepared with loading the reduced graphene (rGO) and zinc oxide on the superfine glass fibre (s-GF) with the three-dimensional network structure by in situ sol-gel process followed by calcination, which aims to achieve synergistic high-efficiency air filtration and rapid response to photocatalytic antibacterial properties under visible light. The air filter showed a three-dimensional network structure based on a rGO/ZnO/s-GF multilayer and exhibited the highest catalytic performance by achieving a 95% degradation effect on rhodamine B within 2 h and achieving 100% antibacterial inactivation of the Escherichia coli and Staphylococcus aureus within 4 h under visible light when the weight ratio of rGO in rGO/ZnO is 1.6%. The air filtration efficiency can also be maintained at 99% after loading ZnO and rGO photocatalytic particles. The spectrum of the photoluminescence (PL), UV-Vis diffuse reflectance spectra (DRS) and electron spin resonance (ESR) indicate that the combination of rGO and ZnO on the s-GF can increase the separation of photogenerated carriers and the specific surface area of the air filter, thereby increasing the photocatalytic response and antibacterial properties of the s-GF air filter under visible light in a short time.

4.
Innovation (Camb) ; 1(3): 100059, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34557723

RESUMO

Coronal mass ejections (CMEs) are large-scale explosions of the coronal magnetic field. It is believed that magnetic reconnection significantly builds up the core structure of CMEs, a magnetic flux rope, during the eruption. However, the quantitative evolution of the flux rope, particularly its toroidal flux, is still unclear. In this paper, we study the evolution of the toroidal flux of the CME flux rope for four events. The toroidal flux is estimated as the magnetic flux in the footpoint region of the flux rope, which is identified by a method that simultaneously takes the coronal dimming and the hook of the flare ribbon into account. We find that the toroidal flux of the CME flux rope for all four events shows a two-phase evolution: a rapid increasing phase followed by a decreasing phase. We further compare the evolution of the toroidal flux with that of the Geostationary Operational Environmental Satellites soft X-ray flux and find that they are basically synchronous in time, except that the peak of the former is somewhat delayed. The results suggest that the toroidal flux of the CME flux rope may be first quickly built up by the reconnection mainly taking place in the sheared overlying field and then reduced by the reconnection among the twisted field lines within the flux rope, as enlightened by a recent 3D magnetohydrodynamic simulation of CMEs.

5.
Oncol Lett ; 17(2): 1531-1536, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30675209

RESUMO

The expression of nitric oxide synthase 1 (NOS1) and adenosine triphosphate-binding cassette sub-family G member 2 (ABCG2) in cervical cancer tissues was investigated. The messenger ribonucleic acid (mRNA) levels of NOS1 and ABCG2 in 40 cervical cancer specimens and 20 normal cervical specimens were detected via reverse transcription-polymerase chain reaction, and the correlation between them was analyzed via Pearsons correlation analysis. The protein expression levels were detected via western blotting. Moreover, the regulatory mode between NOS1 and ABCG2 and the effects on proliferation and apoptosis of cervical cancer cells were analyzed using the lentiviral transfection technique. The mRNA levels of NOS1 and ABCG2 in the cervical cancer group were significantly increased compared with those in the normal cervical control group (P<0.05). There was a positive correlation between NOS1 and ABCG2 mRNA expression levels in cervical cancer tissues (r=1.246, P=0.014). HeLa and C-33A cell lines with relatively high expression levels of NOS1 and ABCG2 were selected for the in vitro study. After interference in the NOS1 expression in HeLa and C-33A cells with sh-NOS1, the protein expression of ABCG2 was also decreased. However, the protein expression level of NOS1 remained unchanged after interference in the ABCG2 expression (P<0.05). After interference in the NOS1 expression, the proliferation capacities of HeLa and C-33A cells were significantly decreased, but the apoptosis levels were obviously increased (P<0.05). The mRNA expression of NOS1 and ABCG2 in cervical cancer tissues is significantly increased. NOS1, as an upstream signal regulator of ABCG2, regulates the growth and apoptosis of tumor cells. Both NOS1 and ABCG2 are important proliferation-promoting oncogenes in cervical cancer, which are expected to provide a certain theoretical basis for the treatment of cervical cancer.

6.
Yonsei Med J ; 60(2): 182-190, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30666840

RESUMO

PURPOSE: This study aimed to investigate the effects of PIK3CA on the sensitivity of acute B lymphocytic leukemia cells (Nalm-6 cells) to chemotherapy drugs. MATERIALS AND METHODS: Children's normal B lymphocytes and Nalm-6 cells were cultured. Nalm-6 cells were transfected with PIK3CA siRNA (siPIK3CA group) or its negative control (PIK3CA-Control group). Normal Nalm-6 cells were named Mock group. Nalm-6 cells transfected by PIK3CA siRNA were treated with Akt inhibitor (siPIK3CA+Akti-1/2 group). mRNA and protein expression was detected by qRT-PCR and Western blot. Proliferation and sensitivity to chemotherapeutic drugs was detected by MTT assay. Cell cycle and apoptosis was explored by low cytometry. Transwell assay was performed to test invasion. RESULTS: PIK3CA mRNA (p=0.008) and protein (p=0.006) expression was higher in Nalm-6 cells than that in normal B lymphocytes. Compared with the Mock group and PIK3CA-Control group, Nalm-6 cells of the siPIK3CA group had lower OD495 values (all p<0.05) and invasion cell numbers (p=0.03 and p=0.025), as well as a higher proportion of G0/G1 phase cells (p=0.020 and p=0.022), percentage of apoptosis (p=0.016 and p=0.022), and inhibition rate (all p<0.05). pAkt expression in the siPIK3CA group (p=0.026 and p=0.031) and siPIK3CA+Akti-1/2 group (p=0.019 and p=0.023) was lower than that in the Mock group. CONCLUSION: PIK3CA silencing inhibited Nalm-6 cell proliferation and invasion, and promoted their apoptosis and sensitivity to chemotherapeutic drugs, potentially through regulation of the PI3K/AKT signaling pathway.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Inativação Gênica , Leucemia/tratamento farmacológico , Leucemia/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Criança , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia/genética , Leucemia/patologia , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética
8.
Zhonghua Fu Chan Ke Za Zhi ; 50(11): 825-9, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-26887769

RESUMO

OBJECTIVE: To investigate the frequeney of four single nucleotide polymorphism (SNP) sites (rs17300539, rs12495941, rs2241766 and rs1501299) of adiponectin gene (ADIPOQ) and to elucidate its role in the pathogenesis of polycystic ovary syndrome (PCOS). METHODS: A total of 207 women with PCOS and 192 controls were recruited. Four ml whole-blood samples were collected in tubes containing ethylene diamine tetraacetic acid (EDTA) by peripheral venous puncture. Genomic DNA was extracted using a QIAamp DNA mini kit. Four SNP sites (rs17300539, rs12495941, rs2241766 and rs1501299) of ADIPOQ were amplified by PCR and then directly sequenced to screen variants. RESULTS: (1) The genotype frequencies of AA of rs17300539 in PCOS was significantly higher than controls [57.5% (119/207) versus 48.4% (93/192), P<0.05]. The genotype frequencies of AA of rs1501299 in PCOS was significantly lower than controls [4.8% (10/207) versus 11.5% (22/192), P<0.05]. While no significant differences were found in rs2241766 and rs12495941 (P>0.05). (2) The allele A of rs17300539 [75.8% (314/414)] and allele C frequeneies of rs1501299 [76.3% (316/414)] in PCOS were significantly higher than controls [67.7% (260/384), 69.0% (265/384), respectively; all P<0.05]. While no significant differences were found in rs2241766 and rs12495941 (P>0.05). (3) Further analysis we found rs17300539 AA genotypes had an increased risk for PCOS compared with GG genotype (OR=2.670, P=0.009), rs1501299 CC genotype had an increased risk for PCOS compared with AA genotypes (OR=2.756, P=0.012); and the difference remained significantly after adjustment for age, testosterone and body mass index (P<0.05). CONCLUSIONS: No significant differences were observed in genotype and allele frequencies between PCOS and controls for rs2241766 and rs12495941. However, we observed an association between rs17300539, rs1501299 and PCOS. rs17300539 and rs1501299 of ADIPOQ perhaps are the susceptibility gene locus of PCOS.


Assuntos
Adiponectina/genética , Predisposição Genética para Doença/genética , Síndrome do Ovário Policístico/diagnóstico , Polimorfismo de Nucleotídeo Único/genética , Alelos , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Síndrome do Ovário Policístico/genética
9.
Exp Biol Med (Maywood) ; 239(12): 1678-87, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24962173

RESUMO

Lectin-like oxidized low density lipoprotein receptor-1 (LOX-1), as the primary oxidized low-density lipoprotein (ox-LDL) receptor on endothelial cells, plays a crucial role in endothelial injury, which is a driving force in the initiation and development of atherosclerosis. Our previous studies have shown that ethanol extract of propolis (EEP) promotes reverse cholesterol transport and inhibits atherosclerotic lesion development. However, the protective effects of EEP against ox-LDL-induced injury in endothelial cells and the underlying mechanisms are still unknown. This study was designed to test the hypothesis that EEP attenuates ox-LDL-induced endothelial oxidative injury via modulation of LOX-1-mediated oxidative stress. Our results showed that exposure of human umbilical vein endothelial cells (HUVECs) to ox-LDL (100 mg/L) led to the decrease in cell viability and increase in lactate dehydrogenase (LDH) release, caspase-3 activation, and apoptosis, whereas pretreatment with EEP (7.5, 15 and 30 mg/L) protected against such damages in a dose-dependent manner. In addition, EEP mitigated ox-LDL uptake by HUVECs and attenuated ox-LDL-upregulated LOX-1 expression both at the mRNA and protein levels. Moreover, EEP suppressed the ox-LDL-induced oxidative stress as assessed by decreased nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, reactive oxygen species (ROS), and malondialdehyde (MDA) generation as well as increased antioxidant enzyme activities. Similar results were observed in the anti-LOX-1 antibody or diphenyleneiodonium (DPI)-pretreated HUVECs. These data indicate that EEP may protect HUVECs from ox-LDL-induced injury and that the mechanism at least partially involves its ability to inhibit endothelial LOX-1 upregulation and subsequent oxidative stress.


Assuntos
Antioxidantes/farmacologia , Células Endoteliais/efeitos dos fármacos , Lipoproteínas LDL/metabolismo , Estresse Oxidativo , Própole/farmacologia , Receptores de LDL/antagonistas & inibidores , Apoptose , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Humanos
10.
Nat Commun ; 3: 747, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22434190

RESUMO

Explosive energy release is a common phenomenon occurring in magnetized plasma systems ranging from laboratories, Earth's magnetosphere, the solar corona and astrophysical environments. Its physical explanation is usually attributed to magnetic reconnection in a thin current sheet. Here we report the important role of magnetic flux rope structure, a volumetric current channel, in producing explosive events. The flux rope is observed as a hot channel before and during a solar eruption from the Atmospheric Imaging Assembly telescope on board the Solar Dynamic Observatory. It initially appears as a twisted and writhed sigmoidal structure with a temperature as high as 10 MK, and then transforms toward a semi-circular shape during a slow-rise phase, which is followed by fast acceleration and onset of a flare. The observations suggest that the instability of the magnetic flux rope triggers the eruption, thus making a major addition to the traditional magnetic-reconnection paradigm.

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