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1.
J Opt Soc Am A Opt Image Sci Vis ; 40(8): 1527-1536, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707108

RESUMO

With the development of orbital angular momentum (OAM) photonic crystal fibers (PCFs) for more efficient communication, fiber claddings are important to the performance. In this paper, the influence of S i O 2 and four new optical materials, which are amethyst, SSK2, SF11, and LaSF09, as cladding materials, on the OAM mode characteristics is studied based on a common PCF for OAM transmission. In addition, the effective index difference, dispersion, confinement loss, and other properties of OAM modes transmitted in the five materials are derived by the finite element method. After in-depth analysis, universal rules can be obtained as guidelines for optimization of PCF in the future for improving the efficiency of optical fiber communication. Through chart analysis, it can be concluded that when materials of high effective refractive indices are used as cladding materials for PCF, the dispersion, nonlinear coefficient, confinement loss, mode purity, and other properties are significantly improved. Lower dispersion and confinement loss are more conducive to long-distance communication transmission. The decrease in nonlinear coefficient represents a better effect in suppressing nonlinear effects, and the increase in numerical aperture and mode purity respectively improves the transmission efficiency and stability of OAM communication. These conclusions provide universal rules for high-quality communication in the future.

2.
Micromachines (Basel) ; 14(8)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37630133

RESUMO

Since the use of chemical fuels is permanently damaging the environment, the need for new energy sources is urgent for mankind. Given that solar energy is a clean and sustainable energy source, this study investigates and proposes a six-layer composite ultra-wideband high-efficiency solar absorber with an annular microstructure. It achieves this by using a combination of the properties of metamaterials and the quantum confinement effects of semiconductor materials. The substrate is W-Ti-Al2O3, and the microstructure is an annular InAs-square InAs film-Ti film combination. We used Lumerical Solutions' FDTD solution program to simulate the absorber and calculate the model's absorption, field distribution, and thermal radiation efficiency (when it is used as a thermal emitter), and further explored the physical mechanism of the model's ultra-broadband absorption. Our model has an average absorption of 95.80% in the 283-3615 nm band, 95.66% in the 280-4000 nm band, and a weighted average absorption efficiency of 95.78% under AM1.5 illumination. Meanwhile, the reflectance of the model in the 5586-20,000 nm band is all higher than 80%, with an average reflectance of 94.52%, which has a good thermal infrared suppression performance. It is 95.42% under thermal radiation at 1000 K. It has outstanding performance when employed as a thermal emitter as well. Additionally, simulation results show that the absorber has good polarization and incidence angle insensitivity. The model may be applied to photodetection, thermophotovoltaics, bio-detection, imaging, thermal ion emission, and solar water evaporation for water purification.

3.
Front Oncol ; 13: 1122284, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37081985

RESUMO

Objective: To evaluate the effects of two genetic variants in the promoter of the miR-143/145 cluster on the risk of epithelial ovarian cancer (EOC) and the prognosis of EOC patients. Study design: Genotypes were determined by the polymerase chain reaction and ligase detection reaction method in 563 EOC patients and 576 healthy women. The expression of miR-143 and miR-145 were detected by quantitative real-time polymerase chain reaction (qRT-PCR) in fifty-two EOC tissues. Results: The rs4705342 CC genotype frequencies in EOC patients were higher than those in the controls (P = 0.014). Furthermore, the CC genotype of rs4705342 was associated with an advanced FIGO stage of EOC patients (P = 0.046). Patients with the rs4705342 CC genotype had shorter progression-free survival (PFS) and overall survival (OS) times than those carrying the TT genotype in multivariable analysis adjusting for clinical variables (HR = 1.30, 95% CI = 1.04-1.62, P = 0.020; HR = 1.33, 95% CI = 1.05-1.70, P = 0.020). In addition, the miR-145 levels were lower in EOC tissues with the rs4705342 CC genotype than in those with the TT genotype (P = 0.005). Conclusion: The CC genotype of rs4705342 was related to an increased risk of EOC and poor prognosis of EOC patients, and rs4705342 may serve as a molecular marker for predicting the development of EOC and the clinical outcome of EOC patients.

4.
Front Genet ; 13: 825261, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495130

RESUMO

Background: Many miRNAs have been demonstrated to be associated with the prognosis of hepatocellular carcinoma (HCC). However, how to combine necroptosis-related miRNAs to achieve the best predictive effect in estimating HCC patient survival has not been explored. Methods: The mRNA and miRNA expression profile were downloaded from a public database (TCGA-LIHC cohort). Necroptosis-related genes were obtained from previous references, and necroptosis-related miRNAs were identified using Pearson analysis. Subsequently, differential expression miRNAs (DEms) were identified in HCC and paracancer normal samples based on necroptosis-related miRNA expression. The whole set with HCC was randomized into a training set and testing set (1:1). LASSO-Cox regression analysis was used to construct an miRNA signature. Multiple statistical methods were used to validate the clinical benefit of signature in HCC patients, including receiver operator characteristic (ROC) curves, Kaplan-Meier survival analyses, and decision curve analysis (DCA). The downstream target genes of miRNAs were obtained from different online tools, and the potential pathways involved in miRNAs were explored. Finally, we conducted RT-qPCR in SK-HEP-1, THLE-3, and HUH-7 cell lines for miRNAs involved in the signature. Results: The results showed that a total of eight specific necroptosis-related miRNAs were screened between HCC and adjacent tissues in the training set. Subsequently, based on the aforementioned miRNAs, 5-miRNA signature (miR-139-5p, hsa-miR-326, miR-10b-5p, miR-500a-3p, and miR-592) was generated by LASSO-Cox regression analysis. Multivariate Cox regression analysis showed that the risk scores were independent prognostic indicators in each set. The area under curves (AUCs) of 1 year, 3 years, 5 years, and 7 years were high in each set (AUC >0.7). DCA analysis also revealed that the risk score had a potential benefit than other clinical characteristics. Meanwhile, survival analysis showed that the high-risk group showed low survival probabilities. Moreover, the results of enrichment analysis showed that specific miRNAs were mainly enriched in the cAMP signaling pathway and TNF signaling pathway. Finally, the results of RT-qPCR were consistent with the prediction results in public databases. Conclusion: Our study establishes a robust tool based on 5-necroptosis-related miRNAs for the prognostic management of HCC patients.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-820996

RESUMO

@# Objective: To investigate the anti-tumor effect of CTL cells on colon cancer xenograft in nude mice after knocking out the immune check point CTLA-4 by CRISPR/Cas9 technology. Methods: A specific small guide RNA (sgRNA) for CTLA-4 was designed to construct sgRNA/Cas9 plasmid, which was then transfected into CTL using a lentiviral vector to obtain CTL cells with CTLA-4 deletion (CTLA-4 KO CTL). The transfection efficiency of the plasmid and the deletion efficiency of CTLA-4 were verified. BALB/c nude mice were randomly divided into two groups to prophylactically inoculate CTLA-4 KO CTL (experimental group) or CTL (control group); 3 days later, the animals of two groups were inoculated with colon cancer cell line LS174-T to observe the tumor formation rate and tumor formation time. After constructing colon cancer xenograft model in nude mice, the animals were randomly divided into two groups, respectively treated with CTLA-4 KO CTL (experimental group) and CTL (control group) cells to observe the tumor growth volume and survival time of mice. The serum levels of TNF-α and IFN-γ in nude mice were detected. Results: sgRNAwas designed and CRSIPR/Cas9 system with lentivirus as vector was successfully constructed. CTL cells were transfected with the established CRSIPR/ Cas9 system, and the highest transfection efficiency was up to (28.80±0.62)%. After transfection, the deletion efficiency of CTLA-4 was detected by Flow cytometry. The CTLA-4 expression of CTLA-4 KO CTL group was significantly lower than that of CTL group [(0.91±0.25)% vs (42.70±2.72)%, P<0.05]. In prophylactic assay, the formation rate of colon cancer xenografts in the experimental group was significantly lower than that in the control group(33.33%vs100%,P<0.05). In treatment assay, the tumor volume in the experimental group was significantly inhibited compared with the control group ([503±23.9] vs [911.2±51.4] mm3, P<0.05), and the survivaltimeoftheexperimentalgroupwassignificantlyprolonged (mediansurvivaltime:78dvs42d,P<0.05); Moreover, the secretion levels of serumTNF-α([268.93±17.04]pg/mlvs[148.26±20.07]pg/ml,P<0.05) and IFN-γ(315.38±18.67 pg/ml vs 202.92±29.32 pg/ml, P<0.05) in the experimental group were significantly higher than those in the control group. Conclusions: The lentiviral vector CRSIPR/Cas9 system is an effective gene editing method; its successful deletion of CTLA-4 in CTL cells can significantly inhibit the tumor formation rate of colon cancer xenografts in nude mice and enhance the anti-tumor effect of CTLon colon cancer xenografts.

6.
Gene ; 636: 36-41, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28888577

RESUMO

T cell-mediated anti-tumor immunity plays a pivotal role in cancer immune surveillance. Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a protein receptor mainly expressed in activated T cells and regulatory T cells. CTLA-4 competes with CD28 for ligand binding and generates inhibitory signals to attenuate T cell activation. The blockade of CTLA-4 mediated immune inhibitory checkpoint has been associated with enhanced anti-tumor immunity. In this study, we use CRISPR-Cas9 system to knock out (KO) CTLA-4 from cytotoxic T lymphocytes (CTLs) and evaluate its effect on the anti-tumor activity of the CTLs. CTLA-4 KO CTLs robustly enhanced tumor cell death by 40% compared to the control and facilitated apoptosis and caspase activities in tumor cells. The knockout of CTLA-4 also increased TNF-α and IFN-γ secretion of the CTLs by approximately 2-fold. The effectiveness of CTLA-4 KO in enhancing anti-tumor activity of the CTLs was verified in vivo using mouse xenograft model. The xenografted mice treated with CTLA-4 KO CTLs demonstrated repressed tumor growth and prolonged survival compared to the control group. Our data suggest that CRISPR targeting CTLA-4 immune checkpoint could significantly improve the anti-tumor activity of CTLs.


Assuntos
Sistemas CRISPR-Cas , Antígeno CTLA-4/genética , Neoplasias/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Apoptose , Antígeno CTLA-4/antagonistas & inibidores , Caspases/metabolismo , Células Cultivadas , Células Matadoras Induzidas por Citocinas/classificação , Citocinas/biossíntese , Células Dendríticas/classificação , Células HCT116 , Humanos , Imunofenotipagem , Camundongos SCID , Neoplasias/patologia , Neoplasias/terapia , Linfócitos T Citotóxicos/classificação
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