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Zeng S, Yi R, Tan F, Sun P, Cheng Q, Zhao X. Lactobacillus plantarum HFY05 Attenuates Carrageenan-Induced Thrombosis in Mice by Regulating NF-κB Pathway-Associated Inflammatory Responses. Front Nutr 2022; 9:813899. [PMID: 35308280 PMCID: PMC8931398 DOI: 10.3389/fnut.2022.813899] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/31/2022] [Indexed: 01/02/2023] Open
Abstract
In this study, a carrageenan-induced thrombus model was established in mice to observe the ability of Lactobacillus plantarum KFY05 (LP-KFY05) to inhibit thrombosis through an NF-κB-associated pathway. Biochemical analysis, microscopical observations, quantitative polymerase chain reactions (qPCR) and western blot analysis were used to examine relevant serum and tissue indexes, and the composition of intestinal microorganisms was determined by examining the abundance of microorganisms in feces. The results showed that LP-KFY05 could markedly reduce the degree of black tail in thrombotic mice; increase the activated partial thromboplastin time (APTT); and decrease the thrombin time (TT), fibrinogen (FIB) level, and prothrombin time (PT). LP-KFY05 could also reduce tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) levels in sera and renal tissues of thrombotic mice. Hematoxylin and eosin staining showed that LP-KFY05 could alleviate renal tissue lesions and tail vein thrombosis. qPCR results showed that LP-KFY05 could down-regulate nuclear factor kappa-B (NF-κB) p65, IL-6, TNF-α, and interferon γ (IFN-γ) mRNA expression in renal tissues, as well as NF-κB p65, intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin mRNA expression in tail vein vascular tissues of thrombotic mice. Western blot analysis showed that LP-KFY05 also down-regulated NF-κB protein expression in renal and tail vein vascular tissues of thrombotic mice. Lastly, LP-KFY05 increased the abundances of Bacteroidetes, Lactobacillus, and Bifidobacterium, as well as decreased the abundance of Firmicutes. These results show that LP-KFY05 can reduce inflammation and inhibit thrombosis in thrombotic mice, and the effects of high concentrations of LP-KFY05 were most pronounced, which were similar to the effects of dipyridamole.
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Gu L, Zhao W, Xu J, Wang B, Cheng Q, Shen D, Xuan Y, Zhao X, Li H, Ma X, Zhang X. Comparison of Transperitoneal and Retroperitoneal Robotic Partial Nephrectomy for Patients With Complete Upper Pole Renal Tumors. Front Oncol 2022; 11:773345. [PMID: 35145902 PMCID: PMC8821917 DOI: 10.3389/fonc.2021.773345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/28/2021] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES We compared the outcomes of transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN) for complete upper pole renal masses (1 point for the "L" component of the RENAL scoring system). MATERIAL AND METHODS We retrospectively reviewed patients who underwent either TRPN or RRPN from 2013 to 2016. Baseline demographics and perioperative, functional, and oncological results were compared. Multivariable analysis was performed to identify factors related to pentafecta achievement (ischemia time ≤25 min, negative margin, perioperative complication free, glomerular filtration rate (eGFR) preservation >90%, and no chronic kidney disease upstaging). RESULTS No significant differences between TRPN vs. RRPN were noted for operating time (110 vs. 114 min, p = 0.870), renal artery clamping time (19 vs. 18 min, p = 0.248), rate of positive margins (0.0% vs. 3.3%, p = 0.502), postoperative complication rates (25.0% vs. 13.3%, p = 0.140). TRPN was associated with a more estimated blood loss (50 vs. 40 ml, p = 0.004). There were no significant differences in pathologic variables, rate of eGFR decline for postoperative 12-month (9.0% vs. 7.1%, p = 0.449) functional follow-up. Multivariate analysis identified that only RENAL score (odd ratio: 0.641; 95% confidence interval: 0.455-0.904; p = 0.011) was independently associated with the pentafecta achievement. CONCLUSIONS For completely upper pole renal masses, both TRPN and RRPN have good and comparable results. Both surgical approaches remain viable options in the treatment of these cases.
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Yang Z, Wang J, Wang J, Li M, Cheng Q, Wang Z, Wang X, Li J, Li Y, Zhang G. 2D WO 3-x Nanosheet with Rich Oxygen Vacancies for Efficient Visible-Light-Driven Photocatalytic Nitrogen Fixation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:1178-1187. [PMID: 35020399 DOI: 10.1021/acs.langmuir.1c02862] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Oxygen vacancy modulation holds great promise for enhancing the photocatalytic activity for efficient nitrogen fixation under mild conditions. In this work, the two-dimensional WO3-x nanosheets with rich oxygen vacancies were prepared using solvothermal synthesis. The WO3-x nanosheets (rich oxygen vacancies) display nice photocatalytic activity for N2 reduction to ammonia with a high yield rate of 82.41 μmol·gcat-1·h-1 under irradiation of visible light (420 nm), which is 3.59 times higher than that of the WO3-x nanoparticles (poor oxygen vacancies). Electron spin resonance (ESR), N2 adsorption-desorption isotherms, and transient photocurrent responses in the N2 or Ar atmosphere experiments proved that the rich oxygen vacancies, which are induced by the nanosheet structure, could serve as active sites for the chemisorption of N2 and facilitate the electron transfer from unsaturated sites to activated N2. Moreover, based on the analysis of banding energy, the oxygen vacancies not only boosted the ability of visible light harvesting but also elevated the defect energy level to the Fermi level, further inhibiting the defect relaxation effect. The findings offer an insight into the design of the efficient photocatalysts via structure engineering and defect engineering for photocatalytic N2 fixation.
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Pan Z, Cheng Q, Chen H, Lin L, Liao W, Guo D, Zhuang J. Protective effect of Rhus chinensis Mill. extract against liver cirrhosis in rats. TROP J PHARM RES 2022. [DOI: 10.4314/tjpr.v20i2.21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Purpose: To study the effect of Rhus chinensis Mill. extract (RCME) on diethylnitrosamine (DEN)-induced liver cirrhosis in rats.
Methods: RCME was obtained by extracting the dried Rhus chinensis Mill. in water. Liver cirrhosis rat model was prepared by injecting with DEN once a week for 8 weeks. After 8th-week of RCME treatment, biochemical index and oxidative stress were determined in DEN-induced liver cirrhosis in rats.
Results: Compared with model group, plasma concentrations of alanine transaminase (ALT, 125.3 ± 4.1 U/L) and aspartate aminotransferase (AST, 152.4 ± 3.5 U/L) decreased significantly (p < 0.01) in the 8th week. Rhus chinensis Mill. extract (RCME) significantly decreased malondialdehyde (MDA, 0.18 ± 0.02 umol/L) and superoxide dismutase (SOD, 0.76 ± 0.05 U/mg protein) in DEN-induced liver cirrhosis in rats (p < 0.01) when compared with model group.
Conclusion: RCME protects against diethylnitrosamine-induced liver cirrhosis in rats. However, further investigations are required to ascertain the plant extract’s suitability for the clinical management of liver cirrhosis.
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Wu X, Peng C, Nelson PT, Cheng Q. Machine Learning Approach Predicts Probability of Time to Stage-Specific Conversion of Alzheimer's Disease. J Alzheimers Dis 2022; 90:891-903. [PMID: 36189595 PMCID: PMC9840816 DOI: 10.3233/jad-220590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND The progression of Alzheimer's disease (AD) varies in different patients at different stages, which makes predicting the time of disease conversions challenging. OBJECTIVE We established an algorithm by leveraging machine learning techniques to predict the probability of the conversion time to next stage for different subjects during a given period. METHODS Firstly, we used Kaplan-Meier (KM) estimation to get the transition curves of different AD stages, and calculated Log-rank statistics to test whether the progression rate between different stages was identical. This quantitatively confirmed the progression rates known in the literature. Then, we developed an approach based on deep learning model, DeepSurv, to predict the probabilities of time-to-conversion. Finally, to help interpret the deep learning model in our approach, we identified important variables contributing the most to the DeepSurv prediction, whose significance were validated with the analysis of variance (ANOVA). RESULTS Our machine learning approach predicted the time to conversion with a high accuracy. For each of the different stages, the concordance index (CI) of our approach was at least 86%, and the integrated Brier score (IBS) was less than 0.1. To facilitate interpretability of the prediction results, our approach identified the top 10 variables for each disease conversion scenario, which were clinicopathologically meaningful, and most of them were also statistically significant. CONCLUSION Our study has the potential to provide individualized prediction for future time course of AD conversions years before their actual occurrence, thus facilitating personalized prevention and intervention strategies to slow down the progression of AD.
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Liu S, Wang X, Yu X, Cheng Q, Johnson LT, Chatterjee S, Zhang D, Lee SM, Sun Y, Lin TC, Liu JL, Siegwart DJ. Zwitterionic Phospholipidation of Cationic Polymers Facilitates Systemic mRNA Delivery to Spleen and Lymph Nodes. J Am Chem Soc 2021; 143:21321-21330. [PMID: 34878786 PMCID: PMC9437927 DOI: 10.1021/jacs.1c09822] [Citation(s) in RCA: 67] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Polymers represent a promising therapeutic platform for extrahepatic messenger RNA (mRNA) delivery but are hampered by low in vivo efficacy due to polyplex serum instability and inadequate endosomal escape following systemic administration. Here, we report the rational design and combinatorial synthesis of zwitterionic phospholipidated polymers (ZPPs) via cationic polymer postmodification by alkylated dioxaphospholane oxides to deliver mRNA to spleen and lymph nodes in vivo. This modular postmodification approach readily produces tunable zwitterionic species for serum resistance and introduces alkyl chains simultaneously to enhance endosomal escape, thereby transforming deficient cationic polymers to efficacious zwitterionic mRNA carriers without the need to elaborately synthesize functional monomers. ZPPs mediated up to 39 500-fold higher protein expression than their parent cationic counterparts in vitro and enabled efficacious mRNA delivery selectively in spleen and lymph nodes following intravenous administration in vivo. This zwitterionic phospholipidation methodology provides a versatile and generalizable postmodification strategy to introduce zwitterions into the side chains of cationic polymers, extending the utility of cationic polymer families for precise mRNA delivery and demonstrating substantial potential for immunotherapeutic applications.
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Lu X, Dong B, Zhu H, Shi Q, Tang L, Su Y, Zhang C, Huang W, Cheng Q. Two-Channel VO 2 Memory Meta-Device for Terahertz Waves. NANOMATERIALS 2021; 11:nano11123409. [PMID: 34947757 PMCID: PMC8705468 DOI: 10.3390/nano11123409] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/11/2021] [Accepted: 12/12/2021] [Indexed: 11/16/2022]
Abstract
Vanadium oxide (VO2), as one of the classical strongly correlated oxides with a reversible and sharp insulator-metal transition (IMT), enables many applications in dynamic terahertz (THz) wave control. Recently, due to the inherent phase transition hysteresis feature, VO2 has shown favorable application prospects in memory-related devices once combined with metamaterials or metasurfaces. However, to date, VO2-based memory meta-devices are usually in a single-channel read/write mode, which limits their storage capacity and speed. In this paper, we propose a reconfigurable meta-memory based on VO2, which favors a two-channel read/write mode. Our design consists of a pair of large and small split-ring resonators, and the corresponding VO2 patterns are embedded in the gap locations. By controlling the external power supply, the two operation bands can be controlled independently to achieve at least four amplitude states, including "00", "01", "10", and "11", which results in a two-channel storage function. In addition, our research may provide prospective applications in fields such as THz switching, photon storage, and THz communication systems in the future.
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Dong X, Wu P, Yan L, Liu K, Wei W, Cheng Q, Liang X, Chen Y, Dai H. Oriented nanofibrous P(MMD-co-LA)/Deferoxamine nerve scaffold facilitates peripheral nerve regeneration by regulating macrophage phenotype and revascularization. Biomaterials 2021; 280:121288. [PMID: 34894585 DOI: 10.1016/j.biomaterials.2021.121288] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 11/12/2021] [Accepted: 11/25/2021] [Indexed: 12/14/2022]
Abstract
Delayed injured nerve regeneration remains a clinical problem, partly ascribing to the lack of regulation of regenerative microenvironment, topographical cues, and blood nourishment. Functional electrospun conduits have been established as an efficacious strategy to facilitate nerve regeneration by providing structural guidance, regulating the regenerative immune microenvironment, and improving vascular regeneration. However, the synthetic polymers conventionally used to fabricate electrospinning scaffolds, such as poly(L-lactic acid), poly(glycolic acid), and poly(lactic-co-glycolic acid), can cause aseptic inflammation due to acidic degradation products. Therefore, a poly[3(S)-methyl-morpholine-2,5-dione-co-lactic] [P(MMD-co-LA)] containing alanine units with good mechanical properties and reduced acid degradation products, was obtained by melt ring-opening polymerization (ROP). Here, we aimed to explore the effect of oriented nanofiber/Deferoxamine (DFO, a hydrophilic angiogenic drug) scaffold in the rapid construction of a favorable regenerative microenvironment, including cell bridge, polarized vascular system, and immune microenvironment. In vitro studies have shown that the scaffold can sustainably release DFO, which accelerates the migration and tube formation of human umbilical vein endothelial cells (HUVECs), as well as the expression of genes related to angiogenesis. The physical clues provided by the arranged nanofibers can regulate the polarization of macrophages and reduce the expression of inflammatory factors. Furthermore, the in vivo results demonstrated a higher M2 polarization level of the oriented nanofibrous scaffold treatment group with reducedinflammation reaction in the injured nerve. Moreover, the in-situ release of DFO up-regulated the expression of HIF1-α and SDF-1α genes, as well as the expression of HIF1-α's target gene VEGF, further promoting revascularization and enhancing nerve regeneration at the defect site. The obtained results provide essential insights on accelerating the creation of the nerve regeneration microenvironment by combining the physiological processes of nerve regeneration with topographical cues and chemical signal induction.
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Wu X, Cheng Q. Algorithmic Stability and Generalization of an Unsupervised Feature Selection Algorithm. ADVANCES IN NEURAL INFORMATION PROCESSING SYSTEMS 2021; 34:19860-19875. [PMID: 36187051 PMCID: PMC9524443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Feature selection, as a vital dimension reduction technique, reduces data dimension by identifying an essential subset of input features, which can facilitate interpretable insights into learning and inference processes. Algorithmic stability is a key characteristic of an algorithm regarding its sensitivity to perturbations of input samples. In this paper, we propose an innovative unsupervised feature selection algorithm attaining this stability with provable guarantees. The architecture of our algorithm consists of a feature scorer and a feature selector. The scorer trains a neural network (NN) to globally score all the features, and the selector adopts a dependent sub-NN to locally evaluate the representation abilities for selecting features. Further, we present algorithmic stability analysis and show that our algorithm has a performance guarantee via a generalization error bound. Extensive experimental results on real-world datasets demonstrate superior generalization performance of our proposed algorithm to strong baseline methods. Also, the properties revealed by our theoretical analysis and the stability of our algorithm-selected features are empirically confirmed.
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Wu X, Peng C, Wilcock DM, Jicha GA, Cheng Q. PRIME uncovers circadian oscillation patterns and links with Alzheimer’s disease in untimed genome‐wide gene expression data across multiple regions of human brain. Alzheimers Dement 2021. [DOI: 10.1002/alz.053266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Peng C, Liu Y, Zhang X, Kang Z, Chen Y, Chen C, Cheng Q. Learning discriminative representation for image classification. Knowl Based Syst 2021; 233. [DOI: 10.1016/j.knosys.2021.107517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Cheng J, Ahmat M, Guo H, Wei X, Zhang L, Cheng Q, Zhang J, Wang J, Si D, Zhang Y, Zhang R. Expression, Purification and Characterization of a Novel Hybrid Peptide CLP with Excellent Antibacterial Activity. Molecules 2021; 26:7142. [PMID: 34885732 PMCID: PMC8659006 DOI: 10.3390/molecules26237142] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 11/20/2021] [Accepted: 11/22/2021] [Indexed: 01/10/2023] Open
Abstract
CLP is a novel hybrid peptide derived from CM4, LL37 and TP5, with significantly reduced hemolytic activity and increased antibacterial activity than parental antimicrobial peptides. To avoid host toxicity and obtain high-level bio-production of CLP, we established a His-tagged SUMO fusion expression system in Escherichia coli. The fusion protein can be purified using a Nickel column, cleaved by TEV protease, and further purified in flow-through of the Nickel column. As a result, the recombinant CLP with a yield of 27.56 mg/L and a purity of 93.6% was obtained. The purified CLP exhibits potent antimicrobial activity against gram+ and gram- bacteria. Furthermore, the result of propidium iodide staining and scanning electron microscopy (SEM) showed that CLP can induce the membrane permeabilization and cell death of Enterotoxigenic Escherichia coli (ETEC) K88. The analysis of thermal stability results showed that the antibacterial activity of CLP decreases slightly below 70 °C for 30 min. However, when the temperature was above 70 °C, the antibacterial activity was significantly decreased. In addition, the antibacterial activity of CLP was stable in the pH range from 4.0 to 9.0; however, when pH was below 4.0 and over 9.0, the activity of CLP decreased significantly. In the presence of various proteases, such as pepsin, papain, trypsin and proteinase K, the antibacterial activity of CLP remained above 46.2%. In summary, this study not only provides an effective strategy for high-level production of antimicrobial peptides and evaluates the interference factors that affect the biological activity of hybrid peptide CLP, but also paves the way for further exploration of the treatment of multidrug-resistant bacterial infections.
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Han J, Song W, Cheng X, Cheng Q, Zhang Y, Liu C, Zhou X, Ren Z, Hu M, Ning T, Xiao L, Zhuang L. Conductivity and Stability Properties of Anion Exchange Membranes: Cation Effect and Backbone Effect. CHEMSUSCHEM 2021; 14:5021-5031. [PMID: 34498428 DOI: 10.1002/cssc.202101446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/03/2021] [Indexed: 06/13/2023]
Abstract
The rise of heterocycle cations, a new class of stable cations, has fueled faster growth of research interest in heterocycle cation-attached anion exchange membranes (AEMs). However, once cations are grafted onto backbones, the effect of backbones on properties of AEMs must also be taken into account. In order to comprehensively study the influence of cations effect and backbones effect on AEMs performance, a series of AEMs were prepared by grafting spacer cations, heterocycles cations, and aromatic cations onto brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) or poly(vinylbenzyl chloride) (PVB) backbones, respectively. Spacer cation [trimethylamine (TMA), N,N-dimethylethylamine (DMEA)]-attached AEMs showed general ion transportation and stability behaviors, but exhibited high cationic reaction efficiency. Heterocycle cation [1-methylpyrrolidine (MPY), 1-methylpiperidine (MPrD)]-attached AEMs showed excellent chemical stability, but their ion conduction properties were unimpressive. Aromatic cation [1-methylimidazole (MeIm), N,N-dimethylaniline (DMAni)]-attached AEMs exhibited superior ionic conductivity, while their poor cations stabilities hindered the application of the membranes. Besides, it was found that PVB-based AEMs had excellent backbone stability, but BPPO-based AEMs exhibited higher OH- conductivity and cation stability than those of the same cations grafted PVB-based AEMs due to their higher water uptake (WU). For example, the ionic conductivities (ICs) of BPPO-TMA and PVB-TMA at 80 °C were 53.1 and 38.3 mS cm-1 , and their WU was 152.3 and 95.1 %, respectively. After the stability test, the IC losses of BPPO-TMA and PVB-TMA were 21.4 and 32.2 %, respectively. The result demonstrated that the conductivity and stability properties of the AEMs could be enhanced by increasing the WU of the membranes. These findings allowed the matching of cations to the appropriate backbones and reasonable modification of the AEM structure. In addition, these results helped to fundamentally understand the influence of cation effect and backbone effect on AEM performance.
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Yu X, Liu S, Cheng Q, Lee SM, Wei T, Zhang D, Farbiak L, Johnson LT, Wang X, Siegwart DJ. Hydrophobic Optimization of Functional Poly(TPAE-co-suberoyl chloride) for Extrahepatic mRNA Delivery following Intravenous Administration. Pharmaceutics 2021; 13:pharmaceutics13111914. [PMID: 34834329 PMCID: PMC8624493 DOI: 10.3390/pharmaceutics13111914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 10/29/2021] [Accepted: 11/04/2021] [Indexed: 01/02/2023] Open
Abstract
Messenger RNA (mRNA) has generated great attention due to its broad potential therapeutic applications, including vaccines, protein replacement therapy, and immunotherapy. Compared to other nucleic acids (e.g., siRNA and pDNA), there are more opportunities to improve the delivery efficacy of mRNA through systematic optimization. In this report, we studied a high-throughput library of 1200 functional polyesters for systemic mRNA delivery. We focused on the chemical investigation of hydrophobic optimization as a method to adjust mRNA polyplex stability, diameter, pKa, and efficacy. Focusing on a region of the library heatmap (PE4K-A17), we further explored the delivery of luciferase mRNA to IGROV1 ovarian cancer cells in vitro and to C57BL/6 mice in vivo following intravenous administration. PE4K-A17-0.2C8 was identified as an efficacious carrier for delivering mRNA to mouse lungs. The delivery selectivity between organs (lungs versus spleen) was found to be tunable through chemical modification of polyesters (both alkyl chain length and molar ratio in the formulation). Cre recombinase mRNA was delivered to the Lox-stop-lox tdTomato mouse model to study potential application in gene editing. Overall, we identified a series of polymer-mRNA polyplexes stabilized with Pluronic F-127 for safe and effective delivery to mouse lungs and spleens. Structure–activity relationships between alkyl side chains and in vivo delivery were elucidated, which may be informative for the continued development of polymer-based mRNA delivery.
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Biesen R, Frese-Schaper M, Enghard P, Cheng Q, Hiepe F, Frese S. Refractory mixed proliferative and membranous lupus nephritis treated with the topoisomerase I inhibitor irinotecan as add-on therapy. Scand J Rheumatol 2021; 51:237-240. [PMID: 34726116 DOI: 10.1080/03009742.2021.1980979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To evaluate the safety and effects of irinotecan, an inhibitor of topoisomerase I, on refractory lupus nephritis. METHOD A patient with refractory lupus nephritis under medication with mycophenolic acid, prednisolone, and hydroxychloroquine was treated with add-on low-dose irinotecan. Irinotecan was applied every fourth week at a dose of 50 mg/m2 for four cycles followed by 100 mg/m2 for another eight cycles. Renal function and anti-double-stranded DNA antibodies as well as blood count for evaluation of side effects were assessed during the treatment with irinotecan. RESULTS Before starting the treatment with irinotecan, a urine protein/creatinine ratio of 1298 mg/g was determined. This declined to 613 mg/g after four cycles with 50 mg/m2 irinotecan and was further reduced to 198 mg/g when using the higher dose of irinotecan. Kidney function remained stable, with creatinine levels of 1.66 mg/dL at the beginning and 1.76 mg/dL at the end of treatment with irinotecan. Importantly, no side effects, such as diarrhoea or neutropenia, were observed during the entire course of treatment. CONCLUSION Administration of low-dose irinotecan as add-on medication for the treatment of refractory lupus nephritis was shown to be safe. Clinical trials are needed to determine whether irinotecan can improve kidney function and the outcome of patients with refractory lupus nephritis.
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Guo HN, Tong YC, Wang HL, Zhang J, Li ZX, Abbas Z, Yang TT, Liu MY, Chen PY, Hua ZC, Yan XN, Cheng Q, Ahmat M, Wang JY, Zhang LL, Wei XB, Liao XD, Zhang RJ. Novel Hybrid Peptide Cathelicidin 2 (1-13)-Thymopentin (TP5) and Its Derived Peptides with Effective Antibacterial, Antibiofilm, and Anti-Adhesion Activities. Int J Mol Sci 2021; 22:11681. [PMID: 34769113 PMCID: PMC8583881 DOI: 10.3390/ijms222111681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 02/08/2023] Open
Abstract
The increasing numbers of infections caused by multidrug-resistant (MDR) pathogens highlight the urgent need for new alternatives to conventional antibiotics. Antimicrobial peptides have the potential to be promising alternatives to antibiotics because of their effective bactericidal activity and highly selective toxicity. The present study was conducted to investigate the antibacterial, antibiofilm, and anti-adhesion activities of different CTP peptides (CTP: the original hybrid peptide cathelicidin 2 (1-13)-thymopentin (TP5); CTP-NH2: C-terminal amidated derivative of cathelicidin 2 (1-13)-TP5; CTPQ: glutamine added at the C-terminus of cathelicidin 2 (1-13)-TP5) by determining the minimal inhibitory concentrations (MICs), minimal bactericidal concentrations (MBCs), propidium iodide uptake, and analysis by scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy). The results showed that CTPs had broad-spectrum antibacterial activity against different gram-positive and gram-negative bacteria, with MICs against the tested strains varying from 2 to 64 μg/mL. CTPs at the MBC (2 × MIC 64 μg/mL) showed strong bactericidal effects on a standard methicillin-resistant Staphylococcus aureus strain ATCC 43300 after co-incubation for 6 h through disruption of the bacterial membrane. In addition, CTPs at 2 × MIC also displayed effective inhibition activity of several S. aureus strains with a 40-90% decrease in biofilm formation by killing the bacteria embedded in the biofilms. CTPs had low cytotoxicity on the intestinal porcine epithelial cell line (IPEC-J2) and could significantly decrease the rate of adhesion of S. aureus ATCC 43300 on IPEC-J2 cells. The current study proved that CTPs have effective antibacterial, antibiofilm, and anti-adhesion activities. Overall, this study contributes to our understanding of the possible antibacterial and antibiofilm mechanisms of CTPs, which might be an effective anti-MDR drug candidate.
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Cheng Q, Xu W, Liu Z, Hao X, Wang Y. Optimal Trajectory Planning of the Variable-Stiffness Flexible Manipulator Based on CADE Algorithm for Vibration Reduction Control. Front Bioeng Biotechnol 2021; 9:766495. [PMID: 34692668 PMCID: PMC8531977 DOI: 10.3389/fbioe.2021.766495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 09/15/2021] [Indexed: 11/18/2022] Open
Abstract
Robotic manipulators are widely used for precise operation in the medical field. Vibration suppression control of robotic manipulators has become a key issue affecting work stability and safety. In this paper an optimal trajectory planning control method to suppress the vibration of a variable-stiffness flexible manipulator considering the rigid-flexible coupling is proposed. Through analyzing the elastic deformation of the variable-stiffness flexible manipulator, a distributed dynamic physical model of the flexible manipulator is constructed based on the Hamilton theory. Based on the mathematical model of the system, the design of the vibration damping controller of the flexible manipulator is proposed, and the control system with nonlinear input is considered for numerical analysis. According to the boundary conditions, the vibration suppression effect of the conventional and the variable-stiffness flexible manipulator is compared. The motion trajectory of the variable-stiffness flexible manipulator and compare the vibration response from different trajectories. Then, with minimum vibration displacement, minimum energy consumption and minimum trajectory tracking deviation as performance goals, the trajectory planning of the variable-stiffness flexible manipulator movement is carried out based on the cloud adaptive differential evolution (CADE) optimization algorithm. The validity of the proposed trajectory planning method is verified by numerical simulation.
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Wang K, Wang H, Cheng Q, Gao C, Wang G, Wu X. Molecular-functionalized engineering of porous carbon nitride nanosheets for wide-spectrum responsive solar fuel generation. J Colloid Interface Sci 2021; 607:1061-1070. [PMID: 34571295 DOI: 10.1016/j.jcis.2021.09.034] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/05/2021] [Accepted: 09/06/2021] [Indexed: 01/30/2023]
Abstract
Carbon nitride (C3N4) is a promising metal-free photocatalyst for solar-to-energy conversion, but bulk carbon nitride (BCN) shows insufficient light absorption, sluggish photocarrier transfer and moderate activity for photocatalysis. Herein, a facile strategy to significantly increase solar spectrum absorption of the functionalized porous carbon nitride nanosheets (MFPCN) via molecule self-assembly engineering coupled thermal polymerization is reported. This strategy can greatly enhance the wide-solar-spectrum absorption of MFPCN up to 1000 nm than most reported carbon nitride-based photocatalysts. Experimental characterizations and theoretical calculations together display that this strategy could introduce hydroxyl groups into the structure of MFPCN as well as the rich pores and active sites at the edges of framework, which can narrow the bandgap and accelerate the transfer and separation of photoinduced carries. As a result, the optimal MFPCN photocatalyst exhibit the excellent photocatalytic hydrogen evolution rate of 7.745 mmol g-1h-1 under simulated solar irradiation, which is ≈13 times that of BCN with remarkable durable CO2 reduction activities. New findings in this work will provide an approach to extend solar spectrum absorption of metal-free catalysts for solar fuel cascades.
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Liu T, Olajide T, Wang W, Cheng Z, Cheng Q, Weng X. Quality detection of tea oil by 19F NMR and 1H NMR. GRASAS Y ACEITES 2021. [DOI: 10.3989/gya.0662201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The nuclear magnetic resonance (NMR) technique was applied to monitor the quality of tea oil herein. The adulteration of virgin tea oil was monitored by 19F NMR and 1H NMR. The 19F NMR technique was used as a new method to detect the changes in quality and hydroperoxide value of tea oil. The research demonstrates that 19F NMR and 1H NMR can quickly detect adulteration in tea oil. High temperature caused a decrease in the ratio D and increase in the total diglyceride content. Some new peaks belonging to the derivatives of hydroperoxides appeared at δ-108.21 and δ-109.05 ppm on the 19F NMR spectrum when the oil was autoxidized and became larger when the hydroperoxide value increased. These results have great significance in monitoring the moisture content, freshness and oxidation status of oils and in detecting adulteration in high priced edible oils by mixing with cheap oils.
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Wu X, Peng C, Nelson PT, Cheng Q. Random forest-integrated analysis in AD and LATE brain transcriptome-wide data to identify disease-specific gene expression. PLoS One 2021; 16:e0256648. [PMID: 34492068 PMCID: PMC8423259 DOI: 10.1371/journal.pone.0256648] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 07/08/2021] [Indexed: 11/19/2022] Open
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder that affects thinking, memory, and behavior. Limbic-predominant age-related TDP-43 encephalopathy (LATE) is a recently identified common neurodegenerative disease that mimics the clinical symptoms of AD. The development of drugs to prevent or treat these neurodegenerative diseases has been slow, partly because the genes associated with these diseases are incompletely understood. A notable hindrance from data analysis perspective is that, usually, the clinical samples for patients and controls are highly imbalanced, thus rendering it challenging to apply most existing machine learning algorithms to directly analyze such datasets. Meeting this data analysis challenge is critical, as more specific disease-associated gene identification may enable new insights into underlying disease-driving mechanisms and help find biomarkers and, in turn, improve prospects for effective treatment strategies. In order to detect disease-associated genes based on imbalanced transcriptome-wide data, we proposed an integrated multiple random forests (IMRF) algorithm. IMRF is effective in differentiating putative genes associated with subjects having LATE and/or AD from controls based on transcriptome-wide data, thereby enabling effective discrimination between these samples. Various forms of validations, such as cross-domain verification of our method over other datasets, improved and competitive classification performance by using identified genes, effectiveness of testing data with a classifier that is completely independent from decision trees and random forests, and relationships with prior AD and LATE studies on the genes linked to neurodegeneration, all testify to the effectiveness of IMRF in identifying genes with altered expression in LATE and/or AD. We conclude that IMRF, as an effective feature selection algorithm for imbalanced data, is promising to facilitate the development of new gene biomarkers as well as targets for effective strategies of disease prevention and treatment.
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Qiao F, Wang Y, Zhang C, Zhou R, Wu Y, Wang C, Meng L, Mao P, Cheng Q, Luo C, Hu P, Xu Z. Comprehensive evaluation of genetic variants using chromosomal microarray analysis and exome sequencing in fetuses with congenital heart defect. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2021; 58:377-387. [PMID: 33142350 DOI: 10.1002/uog.23532] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVE To evaluate comprehensively, using chromosomal microarray analysis (CMA) and exome sequencing (ES), the prevalence of chromosomal abnormalities and sequence variants in unselected fetuses with congenital heart defect (CHD) and to evaluate the potential diagnostic yields of CMA and ES for different CHD subgroups. METHODS This was a study of 360 unselected singleton fetuses with CHD detected by echocardiography, referred to our department for genetic testing between February 2018 and December 2019. We performed CMA, as a routine test for aneuploidy and copy number variations (CNV), and then, in cases without aneuploidy or pathogenic CNV on CMA, we performed ES. RESULTS Overall, positive genetic diagnoses were made in 84 (23.3%) fetuses: chromosomal abnormalities were detected by CMA in 60 (16.7%) and sequence variants were detected by ES in a further 24 (6.7%) cases. The detection rate of pathogenic and likely pathogenic genetic variants in fetuses with non-isolated CHD (32/83, 38.6%) was significantly higher than that in fetuses with isolated CHD (52/277, 18.8%) (P < 0.001), this difference being due mainly to the difference in frequency of aneuploidy between the two groups. The prevalence of a genetic defect was highest in fetuses with an atrioventricular septal defect (36.8%), ventricular septal defect with or without atrial septal defect (28.4%), conotruncal defect (22.2%) or right ventricular outflow tract obstruction (20.0%). We also identified two novel missense mutations (c.2447G>C, p.Arg816Pro; c.1171C>T, p.Arg391Cys) and a new phenotype caused by variants in PLD1. CONCLUSIONS Chromosomal abnormalities were identified in 16.7% and sequence variants in a further 6.7% of fetuses with CHD. ES should be offered to all pregnant women with a CHD fetus without chromosomal abnormality or pathogenic CNV identified by CMA, regardless of whether the CHD is isolated. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.
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Lu L, Zhao Y, Yi G, Li M, Liao L, Yang C, Cho C, Zhang B, Zhu J, Zou K, Cheng Q. Quinic acid: a potential antibiofilm agent against clinical resistant Pseudomonas aeruginosa. Chin Med 2021; 16:72. [PMID: 34362401 PMCID: PMC8343939 DOI: 10.1186/s13020-021-00481-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 07/29/2021] [Indexed: 11/11/2022] Open
Abstract
Background The biofilm state of pathogens facilitates antimicrobial resistance which makes difficult-to-treat infections. In this regard, it has been found that the compounds screened from plant extracts represent one category of the most promising antibiofilm agents. However, the antibiofilm activities and the active ingredients of plant extracts remain largely unexplored. In this background, the study is (1) to screen out the plant extracts with antibiofilm ability against Pseudomonas aeruginosa, and (2) to identify the active ingredients in the plant extracts and elucidate the underlying mechanism of the antibiofilm activities. Methods Micro-broth dilution method, in vitro biofilm model, LC–MS/MS analysis and P. aeruginosa-mouse infection model were adopted to assess the antibiofilm activity. GC–MS analysis was performed to detect the active ingredients in plasma. RNA-Seq, GO analysis, KEGG analysis and RT-qPCR were adopted to elucidate the underlying mechanism of antibiofilm activities against P. aeruginosa. Results Lonicerae Japonicae Flos (LJF) among 13 plants could exert significant inhibitory effects on bacterial biofilm formation, mobility and toxin release in vitro, and it could exert antibiofilm effect in vivo too. Moreover, quinic acid, as one metabolite of chlorogenic acid, was found as an active ingredient in LJF against the biofilm of P. aeruginosa. The active ingredient significantly inhibited EPS secretion in biofilm formation and maturity and could achieve synergistic antibiofilm effect with levofloxacin. It reduced the biofilm formation by regulating core targets in quorum sensing system. In GO process, it was found that the core targets were significantly enriched in multiple biological processes involving locomotion, chemotaxis and motility mediated by flagellum/cilium, which was related to KEGG pathways such as bacterial chemotaxis, oxidative phosphorylation, ribosome, biofilm formation, cyanoamino acid metabolism and quorum sensing. Finally, the binding of quinic acid with core targets rhlA, rhlR and rhlB were validated by molecular docking and RT-qPCR. Conclusions In summary, the study verified the in vitro and in vivo antibiofilm effects of LJF against P. aeruginosa and elucidated the active ingredients in LJF and its conceivable pharmacological mechanism, indicating that quinic acid could have the potential of an antibiofilm agent against P. aeruginosa and related infections. Graphic abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s13020-021-00481-8.
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Gao J, Xu XL, Xu XM, Wei QH, Zhang ZZ, Cheng Q. [Real world research on the growth pattern of preterm children with different birth weight]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2021; 59:665-671. [PMID: 34333919 DOI: 10.3760/cma.j.cn112140-20210204-00106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the physical indices and growth status of preterm children aged 0 to 4 years with different birth weight. Methods: Following the real world research approach, the current study retrospectively collected e-chart information of 8 496 preterm children from the child health care system of the Children's Hospital of Chongqing Medical University from December 2010 to December 2017, with 203 123 full-term children followed up during the same period as controls. Premature children were divided into normal birth weight (NBW) group, low birth weight (LBW) group, and very low birth weight (VLBW) group based on their birth weights. The weight and length development within 48 months of age of preterm boys and girls in each group were measured and recorded to establish a numerical table and analyze the growth levels, growth rate, and proportionality. The t-test or chi-square test was used for between-group comparison. Results: Of the 8 496 preterm children, 4 839 were girls and 3 657 boys, including 525 in the VLBW group, with an average birth weight of (1.28±0.14) kg, 3 862 in the LBW group, with an average birth weight of (2.07±0.28) kg, and 4 109 in the NBW group, with an average birth weight of (2.86±0.35) kg. The weight at the actual age of 2-<3 months ((5.61±0.96) vs. (5.64±0.78) kg in boys, (5.11±0.67) vs. (5.18±0.71) kg in girls) and the length at the actual age of 8-<10 months ((70.3±2.4) vs. (70.6±2.4) cm in boys, (68.9±2.2) vs. (68.9±2.4) cm in girls) in the NBW group reached the average weight and length of full-term children. The difference of physical growth before 24 months of age between LBW and control group decreased as children age, with that of LBW group approaches the average of full-term children after 24 months of age, with a weight difference of 0.64-0.95 kg and height difference of 1.3-1.7 cm. The weight and height of the VLBW group were lower than those of full-term infants (2.80-2.86 kg and 3.3-4.3 cm, respectively) at 48 months of age. During 2-12 months of age, the corresponding values of the VLBW group were higher than that of the LBW and NBW groups by 0.35 kg and 0.71 kg, respectively. However, the corresponding values of the VLBW group were lower than that of the LBW and NBW groups(0.64 kg and 0.76 kg at 0-2 months of age, 1.04 kg and 1.49 kg at 12-48 months of age, respectively). The rates of delayed development, underweight, and emaciation were the highest in the VLBW group (all P<0.01), while the rates of overweight and obesity were the highest in the NBW group, with that of the VLBW group being lower than LBW group (P<0.01) at the age of 24-<36 months. Conclusions: Prior to 4 years of age, the time for preterm children to reach the average physical indices of full-term children differ by birth weights, hence warranting further examination of the corrected gestational age for preterm children. Normal birth weight preterm children present with the highest incidence of overweight and obesity and very low birth weight preterm children present with the highest incidence of growth disorders, marking both groups at high risks of malnutrition.
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Guo S, Li K, Hu B, Li C, Zhang M, Hussain A, Wang X, Cheng Q, Yang F, Ge K, Zhang J, Chang J, Liang X, Weng Y, Huang Y. Membrane-destabilizing ionizable lipid empowered imaging-guided siRNA delivery and cancer treatment. EXPLORATION (BEIJING, CHINA) 2021; 1:35-49. [PMID: 37366466 PMCID: PMC10291568 DOI: 10.1002/exp.20210008] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 06/22/2021] [Indexed: 06/28/2023]
Abstract
One of the imperative medical requirements for cancer treatment is how to establish an imaging-guided nanocarrier that combines therapeutic and imaging agents into one system. siRNA therapeutics have shown promising prospects in controlling life-threatening diseases. However, it is still challenging to develop siRNA formulations with excellent cellular entry capability, efficient endosomal escape, and simultaneous visualization. Herein, we fabricated multifunctional ionizable lipid nanoparticles (iLNPs) for targeted delivery of siRNA and MRI contrast agent. The iLNPs comprises DSPC, cholesterol, PEGylated lipid, contrast agent DTPA-BSA (Gd), and ionizable lipid termed iBL0104. siRNA-loaded iLNPs (iLNPs/siRNA) could be decorated with a tumor targeting cyclic peptide (c(GRGDSPKC)) (termed GARP), or without targeting modification (termed GAP). Data revealed that GARP/siRNA iLNPs exhibited significantly higher cellular entry efficiency than GAP/siRNA iLNPs. GARP/siRNA iLNPs rapidly and effectively escaped from endosome and lysosome after internalization. Compared with GAP/siPLK1, GARP/siPLK1 exhibited better tumor inhibition efficacy in both cell-line derived xenograft and liver cancer patient derived xenograft murine models. In addition, GARP formulation displayed ideal MRI effect in tumor-bearing mice, and was well tolerated by testing animals. Therefore, this study provides an excellent example for achieving imaging-guided and tumor-targeted siRNA delivery and cancer treatment, highlighting its promising potential for translational medicine application.
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Chen MZ, Tang W, Dai JY, Ke JC, Zhang L, Zhang C, Yang J, Li L, Cheng Q, Jin S, Cui TJ. Accurate and broadband manipulations of harmonic amplitudes and phases to reach 256 QAM millimeter-wave wireless communications by time-domain digital coding metasurface. Natl Sci Rev 2021; 9:nwab134. [PMID: 35079409 PMCID: PMC8783670 DOI: 10.1093/nsr/nwab134] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 06/22/2021] [Accepted: 07/20/2021] [Indexed: 12/31/2022] Open
Abstract
We propose a theoretical mechanism and new coding strategy to realize extremely accurate manipulations of nonlinear electromagnetic harmonics in ultrawide frequency band based on a time-domain digital coding metasurface (TDCM). Using the proposed mechanism and coding strategy, we design and fabricate a millimeter-wave (mmWave) TDCM, which is composed of reprogrammable meta-atoms embedded with positive-intrinsic-negative diodes. By controlling the duty ratios and time delays of the digital coding sequences loaded on a TDCM, experimental results show that both amplitudes and phases of different harmonics can be engineered at will simultaneously and precisely in broad frequency band from 22 to 33 GHz, even when the coding states are imperfect, which is in good agreement with theoretical calculations. Based on the fabricated high-performance TDCM, we further propose and experimentally realize a large-capacity mmWave wireless communication system, where 256 quadrature amplitude modulation, along with other schemes, is demonstrated. The new wireless communication system has a much simpler architecture than the currently used mmWave wireless systems, and hence can significantly reduce the hardware cost. We believe that the proposed method and system architecture can find vast application in future mmWave and terahertz-wave wireless communication and radar systems.
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