Publications by authors named "Xuefeng Wang"

889 Publications

Activation of CO by Alkaline-Earth Metal Hydrides: Matrix Infrared Spectra and DFT Calculations of HM(OCH) and (MH)(HCOOH) Complexes (M = Sr, Ba).

Inorg Chem 2021 Jul 22. Epub 2021 Jul 22.

Shanghai Key Lab of Chemical Assessment and Sustainability, School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China.

Reactions of MH (M = Sr, Ba) with CO were explored in pure parahydrogen at 3.5 K using matrix isolation infrared spectroscopy and quantum chemical calculations. The formate complex HM(-OCH) and formic acid complex (MH)(HCOOH) were trapped and identified by isotopic substitutions and density functional theory (DFT) frequency calculations. Natural population analysis and the CO reduction mechanism demonstrate that hydride ion transfer from a metal hydride to a CO moiety facilitates the stabilization of such complexes.
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http://dx.doi.org/10.1021/acs.inorgchem.1c01477DOI Listing
July 2021

Genetic and Functional Characterization of Novel Brown-Like Adipocytes Around the Lamprey Brain.

Front Cell Dev Biol 2021 1;9:674939. Epub 2021 Jul 1.

College of Life Sciences, Liaoning Normal University, Dalian, China.

During the process of vertebrate evolution, many thermogenic organs and mechanisms have appeared. Mammalian brown adipose tissue (BAT) generates heat through the uncoupling oxidative phosphorylation of mitochondria, acts as a natural defense against hypothermia and inhibits the development of obesity. Although the existence, cellular origin and molecular identity of BAT in humans have been well studied, the genetic and functional characteristics of BAT from lampreys remain unknown. Here, we identified and characterized a novel, naturally existing brown-like adipocytes at the lamprey brain periphery. Similar to human BAT, the lamprey brain periphery contains brown-like adipocytes that maintain the same morphology as human brown adipocytes, containing multilocular lipid droplets and high mitochondrion numbers. Furthermore, we found that brown-like adipocytes in the periphery of lamprey brains responded to thermogenic reagent treatment and cold exposure and that lamprey UCP2 promoted precursor adipocyte differentiation. Molecular mapping by RNA-sequencing showed that inflammation in brown-like adipocytes treated with LPS and 25HC was enhanced compared to controls. The results of this study provide new evidence for human BAT research and demonstrate the multilocular adipose cell functions of lampreys, including: (1) providing material energy and protecting structure, (2) generating additional heat and contributing to adaptation to low-temperature environments, and (3) resisting external pathogens.
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http://dx.doi.org/10.3389/fcell.2021.674939DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8281276PMC
July 2021

Geometric shaping optimization of 64-APSK constellation in discrete nonlinear frequency division multiplexing systems.

Opt Lett 2021 Jul;46(14):3368-3371

We experimentally demonstrated a geometric shaped (GS) 64-ary amplitude phase shift keying (64-APSK) eigenvalue transmission. The signal is modulated on the scatter coefficient of a single eigenvalue and linear minimum mean square error (LMMSE) estimator is used to reduce the noise. The channel response is estimated by transmitting a normally distributed 64-APSK constellation through a communication link. Based on the polar coordinates distribution of the received constellation, the diameter distributions for each circle can be obtained so that circles with larger noise can obtain larger judgment width. After optimization, the experimental results show that the Q-factor gain is 1.13 dB under 22 dB received optical signal to noise ratio (OSNR) configuration and 0.88 dB after 900 km transmission compared with normally distributed APSK configuration.
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http://dx.doi.org/10.1364/OL.430391DOI Listing
July 2021

PLOD2 Is a Potent Prognostic Marker and Associates with Immune Infiltration in Cervical Cancer.

Biomed Res Int 2021 28;2021:5512340. Epub 2021 Jun 28.

Department of Obstetrics and Gynecology, NanFang Hospital of Southern Medical University, Guangzhou, 510515 Guangdong Province, China.

Background: PLOD2 is overexpressed in diverse tumors and plays a vital role in tumorigenesis. However, the prognostic value of PLOD2 in cervical cancer (CESC) remains unclear.

Methods: PLOD2 expression and CESC patients' survival data were collected from the Oncomine, GEPIA, UALCAN, and Kaplan-Meier Plotter databases; immunohistochemistry (IHC) was used to validate the expression of PLOD2 in CESC; Gene Set Enrichment Analysis was performed using the STRING and DAVID databases; and the correlations between PLOD2 and cancer immune infiltrates were investigated using the TIMER and TISIDB databases.

Results: We found that the expression level of PLOD2 was increased in various cancers, and meta-analysis in the Oncomine database revealed that PLOD2 was significantly upregulated in CESC compared to that in normal tissues ( < 0.001). In addition, the high expression of PLOD2 was closely related to poor overall survival (OS) and disease-free survival (DFS) in patients with CESC (OS HR = 1.73, = 0.029; DFS HR = 2.60, = 0.018). Functional annotations indicated that differentially expressed PLOD2 were primarily related to protein digestion and absorption pathways and to the collagen fibril organization process. Immune infiltration analysis showed that PLOD2 was highly correlated with B cells, CD4+ T cells, T helper type 2 (Th2) cells, and eosinophils in CESC.

Conclusion: PLOD2 is positively associated with poor prognosis and might be considered a novel diagnostic and prognostic marker for CESC patients.
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http://dx.doi.org/10.1155/2021/5512340DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8260295PMC
June 2021

Antithrombin resistance rescues clotting defect of homozygous prothrombin-Tyr510N dysprothrombinemia.

Thromb Haemost 2021 Jul 13. Epub 2021 Jul 13.

Cardiovascular Biology, Oklahoma Medical Research Foundation, Oklahoma City, United States.

A patient with hematuria in our clinic was diagnosed with urolithiasis. Analysis of the patient's plasma clotting-time indicated that both APTT (52.6 s) and PT (19.4 s) are prolonged and prothrombin activity is reduced to 12.4% of normal, though the patient exhibited no abnormal bleeding phenotype and a prothrombin antigen level of 87.9%. Genetic analysis revealed the patient is homozygous for prothrombin Y510N mutation. We expressed and characterized the prothrombin-Y510N variant in appropriate coagulation assays and found that the specificity constant for activation of the mutant zymogen by factor Xa is impaired ~5-fold. Thrombin generation assay using patient's plasma and prothrombin-deficient plasma supplemented with either wild-type or prothrombin-Y510N revealed that both peak height and time to peak for the prothrombin mutant are decreased however the endogenous thrombin generation potential is increased. Further analysis indicated that the thrombin mutant exhibits resistance to antithrombin and is inhibited by the serpin with ~12-fold slower rate constant. Protein C activation by thrombin-Y510N was also decreased ~10-fold, however, thrombomodulin overcame the catalytic defect. The Na+-concentration-dependence of the amidolytic activities revealed that the dissociation constant for the interaction of Na+ with the mutant has been elevated ~20-fold. These results suggest that Y510 (Y184a in chymotrypsin numbering) belongs to network of residues involved in binding Na+. A normal protein C activation by thrombin-Y510N suggests that thrombomodulin modulates the conformation of the Na+-binding loop of thrombin. The clotting defect of thrombin-Y510N appears to be compensated by its markedly lower reactivity with antithrombin, explaining patient's normal hemostatic phenotype.
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http://dx.doi.org/10.1055/a-1549-6407DOI Listing
July 2021

Safety and efficacy of adjunctive lacosamide in Chinese and Japanese adults with epilepsy and focal seizures: A long-term, open-label extension of a randomized, controlled trial.

Epilepsy Res 2021 Jun 29;176:106705. Epub 2021 Jun 29.

Huashan Hospital Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China. Electronic address:

This Phase III, long-term, open-label extension (OLE) trial (EP0009; NCT01832038) was conducted to evaluate the long-term safety, tolerability, and efficacy of adjunctive lacosamide (100-400 mg/day) in Chinese and Japanese people with epilepsy (PWE) (16-70 years) who had completed a double-blind, randomized, placebo-controlled trial of adjunctive lacosamide (EP0008; NCT01710657). PWE entered the OLE trial on 200 mg/day lacosamide and up to 3 concomitant antiseizure medications. Dose adjustments were permitted to optimize tolerability and seizure reduction. Safety variables were treatment-emergent adverse events (TEAEs) and discontinuations due to TEAEs. Efficacy variables were percent change in focal seizure frequency per 28 days from Baseline of the double-blind trial, ≥50 % and ≥75 % responder rates, seizure-freedom, and proportion of PWE on lacosamide monotherapy. Overall, 473 PWE (74.0 % Chinese and 26.0 % Japanese) were enrolled; 238 (50.3 %) PWE completed the trial and 235 (49.7 %) discontinued, most commonly due to lack of efficacy (81 [17.1 %]), adverse events (55 [11.6 %]), and consent withdrawn (49 [10.4 %]). During the trial, PWE received lacosamide for a median of 1016.0 days (∼3 years), with a total exposure of 1454.8 person-years; 321 (67.9 %) PWE received lacosamide for >24 months, and 246 (52.0 %) for >36 months. The median modal dose of lacosamide was 300 mg/day. Overall, 410/473 (86.7 %) PWE reported TEAEs, 244 (51.6 %) had a TEAE that was considered drug-related, and 49 (10.4 %) discontinued due to a TEAE. The most common TEAEs (≥20 % of PWE) were nasopharyngitis, dizziness, and upper respiratory tract infection. The median reduction in focal seizure frequency per 28 days from Baseline was 57.1 %, and the ≥50 % and ≥75 % responder rates were 57.1 % (269/471) and 29.7 % (140/471), respectively. Among PWE who completed 12, 24, and 36 months of treatment, the 12-, 24-, and 36-month seizure-freedom rates were 3.5 % (13/375), 3.4 % (11/321), and 2.0 % (5/247), respectively. Among PWE exposed to lacosamide for ≥6 months and ≥12 months, the proportions of PWE that maintained continuous monotherapy for ≥6 months and ≥12 months were 5.0 % (21/421) and 5.0 % (19/378), respectively. Overall, lacosamide was well-tolerated as long-term adjunctive therapy in Chinese and Japanese PWE and uncontrolled focal seizures, with improvements in seizure reduction maintained over 36 months of treatment.
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http://dx.doi.org/10.1016/j.eplepsyres.2021.106705DOI Listing
June 2021

Patterns and Predictors of Failure in Recurrent or Refractory Large B-Cell Lymphomas following Chimeric Antigen Receptor (CAR) T-Cell Therapy.

Int J Radiat Oncol Biol Phys 2021 Jul 6. Epub 2021 Jul 6.

Dept. of Blood and Marrow Transplant and Cellular Immunotherapy, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL.

Purpose: Chimeric antigen receptor T-cell (CAR T) therapy is capable of eliciting durable responses in patients with relapsed/refractory (R/R) lymphomas. However, the majority of treated patients relapse. Patterns of failure following CAR T have not been previously characterized and may provide insights into the mechanisms of resistance guiding future treatment strategies.

Methods And Materials: Retrospective analysis of R/R large B-cell lymphoma patients treated with anti-CD19 CAR T at an NCI-designated Comprehensive Cancer Center from 2015 to 2019. Pre- and post-treatment PET/CTs were analyzed to assess the progression of existing (local failures) versus new, non-overlapping lesions (de novo failures) and to identify lesions at high-risk for progression.

Results: A total of 469 pretreatment lesions in 63 patients were identified. At a median follow-up of 12•6 months, 36 (57%) patients recurred. The majority (n=31, 86%) had a component of local failure with 13 (36%) patients exhibiting strictly local failures. Even at progression, 84% of recurrent patients continued to have a subset of pretreatment lesions maintain PET/CT resolution. Lesions at high-risk for local failure included those with a diameter ≥5cm (OR 2•34, 95%CI 1•55-3•55; p<0•001), an SUV≥10 (OR 2•08, 95%CI 1•38-3•12; p<0•001), or that were extranodal (OR 1.49, 95% CI 1.10-2.04; p=0.01). In the 69 patients eligible for survival analysis, those with any lesion ≥5cm (n=46, 67%) experienced inferior PFS (HR 2•41, 95%CI 1•15-5•04; p=0•02) and OS (HR 3•36, 95%CI 1•17-9•96; p=0•02).

Conclusion: The majority of patients who recur following CAR T experience a component of local progression. Furthermore, lesions with high-risk features, particularly large size, were associated with inferior treatment efficacy and patient survival. Taken together, these observations suggest that lesion-specific resistance may contribute to CAR T treatment failure. Locally-directed therapies to high-risk lesions, such as radiotherapy, may be a viable strategy to prevent CAR T failures in select patients.
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http://dx.doi.org/10.1016/j.ijrobp.2021.06.038DOI Listing
July 2021

A phase 2 trial of the histone deacetylase inhibitor panobinostat for graft-versus-host disease prevention.

Blood Adv 2021 07;5(13):2740-2750

Blood & Marrow Transplant & Cellular Immunotherapy.

Immunomodulatory properties of histone deacetylase inhibitors represent a reasonable approach for acute graft-versus-host disease (aGVHD) prevention. We report a phase 2 trial evaluating panobinostat (PANO) administered over 26 weeks, starting on day -5 (5 mg orally 3 times a week) with tacrolimus initiated on day -3 plus sirolimus on day -1, with a median patient age of 58 years (range, 19-72 years) (n = 38). Donor source consisted of HLA 8/8-matched donors, related (n = 13) or unrelated (n = 25), using granulocyte colony-stimulating factor-stimulated peripheral blood stem cells. Myeloablative (n = 18) or reduced-intensity (n = 20) conditioning regimens were used for patients with acute myeloid leukemia (n = 17), myelodysplastic syndrome (n = 13), or other malignancies (n = 8). The cumulative incidence of aGVHD II-IV by day 100 was 18.4% (90% confidence interval [CI], 9.4% to 29.9%). Cumulative incidence of chronic GVHD at 1 year was 31.6% (90% CI, 19.5% to 44.3%). Adverse events related to PANO were thrombocytopenia (n = 5), leukopenia (n = 6), gastrointestinal toxicity (n = 3), rash (n = 4), renal failure/peripheral edema (n = 1), and periorbital edema (n = 1). At 1 year, overall survival was 89.5% (90% CI, 81.6% to 98.0%), relapse-free survival was 78.9% (90% CI, 68.8% to 90.6%), nonrelapse mortality was 2.6% (90% CI, 0.3% to 9.9%), and GVHD relapse-free survival was 60.5% (90% CI, 48.8% to 75.1%). PANO hits histone 3 as early as day 15 in CD8, CD4 and T regs. In conclusion, PANO combination met the primary study end point for aGVHD prevention and warrants further testing. This trial was registered at www.clinicaltrials.gov as #NCT02588339.
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http://dx.doi.org/10.1182/bloodadvances.2021004225DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8288668PMC
July 2021

Intestinal Klebsiella pneumoniae infection enhances susceptibility to epileptic seizure which can be reduced by microglia activation.

Cell Death Discov 2021 Jul 7;7(1):175. Epub 2021 Jul 7.

Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China.

Epilepsy is a common nervous system disease, and the existing theory does not fully clarify its pathogenesis. Recent research suggests that intestinal microbes may be involved in the development of epilepsy, but which microbe is involved remains unclear. We used 16s rRNA sequencing to identify the most relevant gut microbe. To determine the relationship between this microbe and epilepsy, we used an animal model. In addition, western blotting and immunofluorescence, as well as inhibitor studies, were used to evaluate and confirm the role of microglia in this process. In this study, we first report an increase in gut Klebsiella pneumoniae in patients with epilepsy. Subsequently, animal studies revealed that Klebsiella pneumoniae in the intestinal tract affects seizure susceptibility and activates microglial cells to release inflammatory factors. Furthermore, the inflammatory response of microglial cells plays a protective role in the seizure susceptibility caused by an increased abundance of Klebsiella pneumoniae. Our results suggest that gut disruption may be involved in seizure regulation and microglia protect the brain against seizure under this condition. These findings provide a new perspective for research on the pathogenesis and prevention of epilepsy.
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http://dx.doi.org/10.1038/s41420-021-00559-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8263697PMC
July 2021

Microfluidic chip grafted with integrin tension sensors for evaluating the effects of flowing shear stress and ROCK inhibitor on platelets.

Lab Chip 2021 Jun 28. Epub 2021 Jun 28.

Electrical and Computer Engineering Department, Iowa State University, Ames, USA50011.

Integrins are key players in platelet adhesion and aggregation. Integrin molecular tensions, the forces transmitted by integrin molecules, are regulated by both mechanical and biochemical cues, and the outside-in and inside-out signaling has been extensively studied. While the mechanical properties of platelets at static status have been studied by atomic force microscopy, traction force microscopy and tension sensors, the biomechanical properties of flowing platelets remain elusive. Herein, we report microfluidic chips grafted with integrin tension sensors for microfluidic-force mapping in platelets. Specifically, the process of integrin αIIbβ3 mediating tension transmission and platelet adhesion under low flow rates has been obtained, and the process of platelet clustering at post-stenotic regions has been demonstrated. We found that flowing shear force can postpone the integrin-mediated tension transmission and platelet adhesion. We further evaluated the effect of Y-27632, a ROCK inhibitor that has been proven to reduce integrin-mediated platelet adhesion, at a series of concentrations and demonstrated that microfluidic chips with integrin tension sensors are sensitive to the concentration-dependent effects of Y-27632. Given their low cost and scalable throughput, these chips are ideal technical platforms for biological studies of platelets at flowing status and for platelet inhibitor or potential antiplatelet drug screening.
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http://dx.doi.org/10.1039/d1lc00259gDOI Listing
June 2021

Structural Analysis of a Novel Aspartic-Type Endopeptidase from Seeds and Its Milk-Clotting Properties.

J Agric Food Chem 2021 Jul 28;69(26):7377-7387. Epub 2021 Jun 28.

College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China.

A novel aspartic-type endopeptidase was previously obtained from seeds; however, its specific milk-clotting properties have remained unclear. Here, we used various biophysical and molecular simulation approaches for characterizing the structure and function of the aspartic-type endopeptidase. The endopeptidase was preferentially active toward κ-casein (CN) and hydrolyzed it more than calf rennet; however, its ability to hydrolyze α-CN and β-CN was weaker than that of calf rennet. The endopeptidase cleaved κ-CN at Gln135-Asp136 and generated a 15 588.18 Da peptide with 135 amino acids. We further simulated the docking complex of the endopeptidase and κ-CN and found out that they possibly combined with each other via hydrogen bonds. The flocculation reaction between the endopeptidase and κ-CN indicated that milk coagulation occurred within 60 min. Overall, our observations suggest that the aspartic-type endopeptidase can be a potential rennet alternative for cheese making.
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http://dx.doi.org/10.1021/acs.jafc.1c02591DOI Listing
July 2021

All-optical polarization split of the signal and LO for a bi-directional self-homodyne coherent system.

Opt Lett 2021 Jun;46(12):2819-2822

In this Letter, we propose a cost-efficient bi-directional (BiDi) polarization-multiplexed self-homodyne coherent detection (SHCD) system, in which only one fiber link and one adaptive polarization controller (APC) are required. By employing the correlation of the state of polarization (SOP) between the upstream and downstream light, one APC is capable of stabilizing SOPs of the counterpropagating waves at the same time. The signal and local oscillator (LO) can be optically split by a polarization beam splitter (PBS), relaxing pressure of the digital signal processing (DSP) and simplifying the coherent receiver. The impact induced by polarization cross talk and delay mismatch is collectively investigated by theoretical analysis and simulation. Finally, the proposed scheme is experimentally verified through 120 Gbit/s 16-quadrature amplitude modulation (16-QAM) transmission, achieving a satisfying laser-linewidth tolerance of 10 MHz and a polarization rotation tolerance of up to 45 rad/s.
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http://dx.doi.org/10.1364/OL.427789DOI Listing
June 2021

Cleavage of the N≡N Triple Bond and Unpredicted Formation of the Cyclic 1,3-Diaza-2,4-Diborete (FB) N from N and Fluoroborylene BF.

Angew Chem Int Ed Engl 2021 Jul 26;60(31):17205-17210. Epub 2021 Jun 26.

Institut für Chemie und Biochemie - Anorganische Chemie, Freie Universität Berlin, Fabeckstrasse 34-36, 14195, Berlin, Germany.

A complete cleavage of the triple bond of N by fluoroborylene (:BF) was achieved in a low-temperature N matrix by the formation of the four-membered heterocycle FB(μ-N) BF, which lacks a trans-annular N-N bond. Additionally, the linear complex FB=N-N=BF and cyclic FB(η -N ) were formed. These novel species were characterized by their matrix infrared spectra and quantum-chemical calculations. The puckered four-membered-ring B N complex shows a delocalized aromatic two-electron π-system in conjugation with the exo-cyclic fluorine π lone pairs. This work may contribute to a rational design of catalysts based on borylene for artificial dinitrogen activation.
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http://dx.doi.org/10.1002/anie.202106984DOI Listing
July 2021

Viral and host transcriptomes in SARS-CoV-2 infected human lung cells.

J Virol 2021 Jun 9:JVI0060021. Epub 2021 Jun 9.

Institute of Military Veterinary Medicine, Academy of Military Medical Sciences, Changchun, 130122, P. R. China.

Coronaviruses are commonly characterized by a unique discontinuous RNA transcriptional synthesis strategy guided by transcription-regulating sequences (TRSs). However, the details of RNA synthesis in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have not been fully elucidated. Here, we present a time-scaled, gene-comparable transcriptome of SARS-CoV-2, demonstrating that ACGAAC functions as a core TRS guiding the discontinuous RNA synthesis of SARS-CoV-2 from a holistic perspective. During infection, viral transcription, rather than genome replication, dominates all viral RNA synthesis activities. The most highly expressed viral gene is the nucleocapsid gene, followed by ORF7 and ORF3 genes, while the envelope gene shows the lowest expression. Host transcription dysregulation keeps exacerbating after viral RNA synthesis achieves to the top. The most enriched host pathways are metabolism-related. Two of them (cholesterol and valine metabolism) affect viral replication in reverse. Furthermore, the activation of numerous cytokines emerges before the large-scale viral RNA synthesis. SARS-CoV-2 is responsible for the current severe global health emergency that began at the end of 2019. Although the universal transcriptional strategies of coronaviruses are preliminarily understood, the details of RNA synthesis, especially the time-matched transcription level of each SARS-CoV-2 gene and the principles of subgenomic mRNA synthesis, are not clear. The coterminal subgenomic mRNAs of SARS-CoV-2 present obstacles in identifying the expression of most genes by PCR-based methods, which is exacerbated by the lack of related antibodies. Moreover, SARS-CoV-2-related metabolic imbalance and cytokine storm are receiving increasing attention from both clinical and mechanistic perspectives. Our transcriptomic research provides information on both viral RNA synthesis and host responses, in which the transcription-regulating sequences and transcription levels of viral genes are demonstrated, and the metabolic dysregulation and cytokine levels identified at the host cellular level support the development of novel medical treatment strategies.
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http://dx.doi.org/10.1128/JVI.00600-21DOI Listing
June 2021

Infrared Spectroscopy of Solvation in the TaO Hydrolysis Reaction.

J Phys Chem A 2021 Jun 4;125(23):5054-5060. Epub 2021 Jun 4.

Department of Chemistry, Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 2005 Songhu Road, Shanghai 200438, China.

The solvent effect of the TaO reaction with water molecules in the gas phase is examined. Stoichiometric TaO(HO) cations are generated by the laser vaporization of a tantalum metal target in the pulsed supersonic expansion of HO/He mixed gas. The infrared photodissociation spectra of TaO(HO) cations are measured using the argon-tagging technology in the 2800-3850 cm region. Density functional theory calculations are carried out to identify the observed infrared bands and elucidate the reaction mechanism. In the TaO reaction with one HO molecule, both the hydrated adduct HO-TaO and dihydroxide TaO(OH) are generated. The coexistence of tetrahydroxide Ta(OH) and hydrated dihydroxide HO-TaO(OH) is seen when the second HO molecule is involved. However, only the hydrated HO-Ta(OH) product is obtained in the TaO reaction with three HO molecules. Theoretical calculations indicate that in the reaction, the formation of a six-membered cyclic transition state through the hydrogen bond lowers the energy barrier significantly, which promotes the transfer of the hydrogen of hydrated adducts to generate di- and tetrahydroxides.
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http://dx.doi.org/10.1021/acs.jpca.1c03185DOI Listing
June 2021

S(vi) in three-component sulfonamide synthesis: use of sulfuric chloride as a linchpin in palladium-catalyzed Suzuki-Miyaura coupling.

Chem Sci 2021 Apr 6;12(18):6437-6441. Epub 2021 Apr 6.

School of Pharmaceutical and Materials Engineering, Institute for Advanced Studies, Taizhou University 1139 Shifu Avenue Taizhou 318000 China

Sulfuric chloride is used as the source of the -SO- group in a palladium-catalyzed three-component synthesis of sulfonamides. Suzuki-Miyaura coupling between the generated sulfamoyl chlorides and boronic acids gives rise to diverse sulfonamides in moderate to high yields with excellent reaction selectivity. Although this transformation is not workable for primary amines or anilines, the results show high functional group tolerance. With the solving of the desulfonylation problem and utilization of cheap and easily accessible sulfuric chloride as the source of sulfur dioxide, redox-neutral three-component synthesis of sulfonamides is first achieved.
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http://dx.doi.org/10.1039/d1sc01351cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8115270PMC
April 2021

Anionic Effect on Enhancing the Stability of a Solid Electrolyte Interphase Film for Lithium Deposition on Graphite.

Nano Lett 2021 Jun 3;21(12):5316-5323. Epub 2021 Jun 3.

Key Laboratory for Renewable Energy, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

Graphitic carbons and their lithium composites have been utilized as lithium deposition substrates to address issues such as the huge volume variation and dendritic growth of lithium. However, new problems have appeared, including the severe exfoliation of the graphite particles and the instability of the solid electrolyte interphase (SEI) film when metallic lithium is plated on the graphite. Herein, we enhance the stability of the SEI film on the graphite substrate for lithium deposition in an electrolyte of lithium bis(fluorosulfonyl)imide (LiFSI) dissolved in the carbonate solvent, thereby improving the lithium plating/stripping cycle on it. The FSI anion was found to be responsible for the formation of a compact SEI film under the lithium plating potential and could protect the graphite substrate. These findings refresh the understanding of the SEI stability and provide a suggestion on the design and development of electrolytes for the lithium batteries.
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http://dx.doi.org/10.1021/acs.nanolett.1c01436DOI Listing
June 2021

Proteomics analysis of the bio-functions of Dregea sinensis stems provides insights regarding milk-clotting enzyme.

Food Res Int 2021 06 26;144:110340. Epub 2021 Mar 26.

College of Food Science and Technology, Yunnan Agricultural University, Kunming 650201, Yunnan, China. Electronic address:

Dregea sinensis (D. sinensis) stems have traditionally been used as milk coagulant in Dali of Yunnan Province, China. In this study, proteomics was used to investigate the bio-functions of D. sinensis stem proteins, leading to the purification and identification of the milk-clotting enzyme. A total of 205 proteins mainly involved in the catalytic and metabolic processes were identified, of which 28 proteins exhibited hydrolase activity. Among the 28 proteins, we focused on two enzymes (M9QMC9 and B7VF65). Based on proteomics, a cysteine protease (M9QMC9) with a molecular weight of 25.8 kDa and milk-clotting activity was purified from D. sinensis stems using double ammonium sulfate precipitation and was confirmed using liquid chromatography-mass spectrometry (LC-MS/MS). The milk-clotting temperature using the purified enzyme was around 80 °C (specific activity at 314.38 U/mg), and it was found to be stable in the pH range of 6-9 in NaCl concentration of <0.8 mol/L. These findings indicated that the enzyme isolated from D. sinensis stems has potential in the dairy and food sectors, especially in the cheese-making industry.
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http://dx.doi.org/10.1016/j.foodres.2021.110340DOI Listing
June 2021

Ternary Electrochemiluminescence Biosensor Based on DNA Walkers and AuPd Nanomaterials as a Coreaction Accelerator for the Detection of miRNA-141.

ACS Appl Mater Interfaces 2021 Jun 25;13(22):25783-25791. Epub 2021 May 25.

School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, P. R. China.

In this study, a ternary electrochemiluminescence (ECL) sensing platform coupled with a multiple signal amplification strategy was proposed for ultrasensitive detection of miRNA-141. The initial signal amplification was achieved via three-dimensional reduced graphene oxide (3D-rGO)@Au nanoparticles (NPs) to form an excellent conductive layer. Then, AuPd NPs as a coreaction accelerator was introduced into the -(4-aminobutyl)--(ethylisoluminol) (ABEI)-HO system to facilitate the transformation from HO to excess superoxide anion radicals (O), which further amplified the ECL emission of ABEI, leading to a significant increase of the ECL signal. Meanwhile, in the presence of miRNA-141 and T7 Exonuclease (T7 Exo), the self-assembled DNA swing arm can be driven to walk autonomously. The DNA walker reaction could result in the release of numerous labeled luminophores, which could react to achieve an extremely weak ECL signal. Surprisingly, the established ECL sensor platform for the detection of miRNA-141 demonstrated excellent sensitivity with a low detection limit of 31.9 aM in the concentration range from 100 aM to 1 nM. Consequently, the designed strategy greatly improves the luminous efficiency of the ternary ECL system and provides a special approach for the detection of nucleic acids and biomarkers in clinical and biochemical analysis.
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http://dx.doi.org/10.1021/acsami.1c05368DOI Listing
June 2021

Metal Oxo-Fluoride Molecules OMF (M = Mn and Fe; = 1-4) and OMnF: Matrix Infrared Spectra and Quantum Chemistry.

Inorg Chem 2021 Jun 24;60(11):7687-7696. Epub 2021 May 24.

Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education, Tsinghua University, Beijing 100084, China.

On reacting laser-ablated manganese or iron difluorides with O or O during codeposition in solid neon or argon, infrared absorptions of several new metal oxo-fluoride molecules, including OMF, (η-O)MF, (η-O)MF, (η-O)MF (M = Mn and Fe), and OMnF, have been observed. Quantum chemical density functional and multiconfiguration wavefunction calculations have been applied to characterize these new products by their geometric and electronic structures, vibrations, charges, and bonding. The assignment of the main vibrational absorptions as dominant symmetric or antisymmetric M-F or M-O stretching modes is confirmed by oxygen isotopic shifts and quantum chemical calculations of frequencies and thermal stabilities. The tendency of Fe to form polyoxygen complexes in lower oxidation states than the preceding element Mn is affirmed experimentally and supported theoretically. The M-F stretching frequencies of the isolated metal oxo-fluorides may provide a scale for the local charge on the MF sites in active energy conversion systems. The study of these species provides insights for understanding the trend of oxidation state changes across the transition-metal series.
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http://dx.doi.org/10.1021/acs.inorgchem.0c03806DOI Listing
June 2021

Fenchel duality of Cox partial likelihood with an application in survival kernel learning.

Artif Intell Med 2021 06 24;116:102077. Epub 2021 Apr 24.

Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612, USA. Electronic address:

The Cox proportional hazard model is one of the most widely used methods in modeling time-to-event data in the health sciences. Due to the simplicity of the Cox partial likelihood function, many machine learning algorithms use it for survival data. However, due to the nature of censored data, the optimization problem becomes intractable when more complicated regularization is employed, which is necessary when dealing with high dimensional omic data. In this paper, we show that a convex conjugate function of the Cox loss function based on Fenchel duality exists, and provide an alternative framework to optimization based on the primal form. Furthermore, the dual form suggests an efficient algorithm for solving the kernel learning problem with censored survival outcomes. We illustrate performance and properties of the derived duality form of Cox partial likelihood loss in multiple kernel learning problems with simulated and the Skin Cutaneous Melanoma TCGA datasets.
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http://dx.doi.org/10.1016/j.artmed.2021.102077DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8159024PMC
June 2021

Activating Titanium Metal with H Plasma for the Hydrogen Evolution Reaction.

ACS Appl Mater Interfaces 2021 Jun 19;13(21):24682-24691. Epub 2021 May 19.

Science and Technology on Surface Physics and Chemistry Laboratory, Jiangyou 621908, China.

Developing a high-performance nonprecious metal electrocatalyst for water splitting is a strong demand for the large-scale application of electrochemical H production. In this work, we design a facile and scalable strategy to activate titanium metal for the hydrogen evolution reaction (HER) in alkaline media through incorporating hydrogen into the α-Ti crystal lattice by H plasma bombardment. Benefiting from the accelerated charge transfer and enlarged electrochemical surface area after H plasma treatment, the H-incorporated Ti shows remarkably enhanced HER activity with a much lower overpotential at -10 mA cm by 276 mV when compared to the pristine Ti. It is revealed that the retention of the incorporated H(D) atoms in the Ti crystal lattice during HER accounts for the durable feature of the catalyst. Density functional theory calculations demonstrate the effectiveness of hydrogen incorporation in tuning the adsorption energy of reaction species via charge redistribution. Our work offers a novel route to activate titanium or other metals by H incorporation through a controllable H plasma treatment to tune the electronic structure for water splitting reactions.
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http://dx.doi.org/10.1021/acsami.1c02646DOI Listing
June 2021

Valproic acid-induced encephalopathy: A review of clinical features, risk factors, diagnosis, and treatment.

Epilepsy Behav 2021 07 15;120:107967. Epub 2021 May 15.

Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China. Electronic address:

Valproic acid (VPA), or sodium valproate, is a commonly used medication for seizure disorders, migraines, and mental illness. Although VPA is relatively safe, it still has several adverse effects; among these, VPA-induced encephalopathy is the most serious. Valproic acid-induced encephalopathy mainly manifests as acute or subacute encephalopathy and has been associated with hyperammonemia, L-carnitine deficiency, and urea cycle enzyme dysfunction. Delayed identification of VPA-induced encephalopathy could be potentially fatal. Here, we perform an extensive review of relevant literature pertaining to VPA-induced encephalopathy, including its epidemiology, clinical features, possible pathophysiology, risk factors, diagnosis, and treatment.
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http://dx.doi.org/10.1016/j.yebeh.2021.107967DOI Listing
July 2021

Relapsed Primary Central Nervous System Lymphoma: Current Advances.

Front Oncol 2021 29;11:649789. Epub 2021 Apr 29.

Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, Chongqing, China.

Primary central nervous system lymphoma is an invasive malignant lymphoma confined to the central nervous system. Although patients undergoing first-line treatment can achieve complete response, most of them still relapse within two years. Relapsed lymphoma is derived from occult lymphoma cells, and B cell receptor pathway activation and immune escape are the key mechanisms for the pathogenesis of PCNSL. Most relapses are in the central nervous system, a small number of relapses are isolated systemic relapses, and clinical symptoms occur early and vary. Current treatments for relapse include high-dose methotrexate rechallenge and other regimens of chemotherapy, whole-brain radiation therapy, hematopoietic stem-cell transplantation, targeted therapy and immunotherapy, which have become promising treatments. The overall prognosis of relapsed PCNSL is very poor, although it is affected by many factors. This article summarizes the mechanisms, related factors, clinical features, follow-up, treatment and prognosis of relapsed primary central nervous system lymphoma.
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http://dx.doi.org/10.3389/fonc.2021.649789DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8118624PMC
April 2021

A novel lncRNA SOX2OT promotes the malignancy of human colorectal cancer by interacting with miR-194-5p/SOX5 axis.

Cell Death Dis 2021 May 15;12(5):499. Epub 2021 May 15.

Department of Nephrology, First Hospital of Jilin University, Jilin, 130021, China.

Long noncoding RNAs (lncRNAs) show emerging roles in colorectal cancer (CRC) development and are considered to be involved in the potential mechanism of tumor malignancy. While Sox2 overlapping transcript (SOX2OT) has been implicated in the progression of multiple cancers, its role in CRC remains to be explored. In this study, in situ hybridization (ISH) and qRT-PCR were performed to establish the functional relationships between SOX2OT and CRC deranged in CRC tissue and cells. Subsequently, SOX2OT shRNAs vectors were transfected into CRC cells to performed loss-of-function assays to detect the potential role of SOX2OT on proliferation and metastasis in vitro and vivo. The results showed SOX2OT was an oncogene that was up-regulated in human CRC tissues and cell lines. SOX2OT silencing suppressed cell proliferation, migration, and invasion in CRC cells in vitro, and inhibited tumorigenesis in the mouse xenografts. Bioinformatic predictive analysis coupled with the dual-luciferase reporter, RNA immunoprecipitation (RIP), and functional rescue assay elucidated the mechanistic network of the SOX2OT-miR-194-5p-SOX5 axis in CRC. Mechanistically, SOX2OT acted as a competing endogenous RNA (ceRNA) to upregulate SOX5 by sponging miR-194-5p. Downregulated SOX2OT boosted miR-194-5p expression, thus decreased the protein level of SOX5, which suppresses tumorgenesis of CRC.
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http://dx.doi.org/10.1038/s41419-021-03756-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8124073PMC
May 2021

HMGB1 knockdown increases the radiosensitivity of esophageal squamous cell carcinoma by regulating the expression of molecules involved in DNA repair.

Oncol Lett 2021 Jul 29;22(1):503. Epub 2021 Apr 29.

Department of Oncology, Jingjiang People's Hospital, The Seventh Affiliated Hospital of Yangzhou University, Jingjiang, Jiangsu 214500, P.R. China.

Radiotherapy is an effective therapeutic strategy in esophageal squamous cell carcinoma (ESCC). However, acquired radioresistance of cancer cells leads to radiotherapy failure. The present study aimed to investigate the mechanisms of the effect of high mobility group box 1 (HMGB1) on the radiation sensitivity of ESCC. Small interfering RNA (si) transfection was used to generate three groups of TE-1 cells (TE-1, negative control and TE-1+siHMGB1), and the protein expression levels of HMGB1 in TE-1 cells were detected by western blotting. These groups of TE-1 cells were irradiated with different doses (0, 2, 4, 6 and 8 Gy) of X-rays after transfection. Subsequently, the viability of TE-1 cells was detected using an MTT assay, and the survival fraction of TE-1 cells was observed using a colony formation assay. The apoptotic rate, reactive oxygen species (ROS) content and levels of phosphorylated (p)-histone H2AX at S139 (p-γH2AX) of the cells were detected by flow cytometry. The alterations in mRNA expression levels of nicotinamide adenine nucleotide phosphate oxidase (NOX)1 and NOX5 were detected by reverse transcription-quantitative PCR, while the changes in protein levels of caspase-3, poly(ADP-ribose) polymerase, p-p38, p-ERK1/2 and p-JNK were detected by western blotting. The results revealed that HMGB1 knockdown significantly decreased cell viability, and the apoptosis rate of TE-1 cells transfected with siHMGB1 combined with radiation treatment was increased compared with that in cells with either siHMGB1 transfection or radiation treatment alone. HMGB1 knockdown increased nicotinamide adenine nucleotide phosphate oxidase-mediated ROS production and induced DNA damage via the MAPK signaling pathway, which may promote apoptosis and radiosensitivity after radiation in TE-1 cells. In conclusion, targeting HMGB1 may represent a promising strategy to increase the efficacy of radiation therapy for ESCC.
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http://dx.doi.org/10.3892/ol.2021.12764DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8114541PMC
July 2021

Development of a -based counterselectable system for targeted gene deletion in .

J Zhejiang Univ Sci B 2021 May;22(5):383-396

School of Life Sciences, North China University of Science and Technology, Tangshan 063210, China.

produces many valuable and important biomolecules with clinical and pharmaceutical applications. The development of simple and highly efficient gene editing tools for genetic modification of is highly desirable. In this study, we developed a screening system for targeted gene knockout using a uracil auxotrophic host (Δ) resistant to the highly toxic uracil analog of 5-fluoroorotic acid (5-FOA) converted by PyrF, and a non-replicative vector pKC1132-pyrF carrying the complemented gene coding for orotidine-5'-phosphate decarboxylase. The gene acts as a positive selection and counterselection marker for recombinants during genetic modifications. Single-crossover homologous integration mutants were selected on minimal medium without uracil by reintroducing along with pKC1132-pyrF into the genome of the mutant Δ at the targeted locus. Double-crossover recombinants were generated, from which the gene, plasmid backbone, and targeted gene were excised through homologous recombination exchange. These recombinants were rapidly screened by the counterselection agent, 5-FOA. We demonstrated the feasibility and advantage of using this based screening system through deleting the gene, which encodes the cluster-situated regulator that directly activates oxytetracycline biosynthesis in M4018. This system provides a new genetic tool for investigating the genetic characteristics of species.
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http://dx.doi.org/10.1631/jzus.B2000606DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8110465PMC
May 2021

2-Mercaptoethanol (2-ME)-based IATs or Polybrene method mitigates the interference of daratumumab on blood compatibility tests.

Hematology 2021 Dec;26(1):365-370

Department of Blood Transfusion, Changzheng Hospital, Naval Medical University, Shanghai, People's Republic of China.

Objectives: Treating red blood cells (RBCs) with dithiothreitol (DTT) is a wildly-recommended to overcome the interference of the daratumumab (DARA) with blood compatibility testing. Nevertheless, DTT can be hard to obtain in the clinical laboratory, while its use in routine practice may be time-consuming. In the following study, we explored the feasibility of using a commercial 2-mercaptoethanol (2-ME) working solution or the time-saving Polybrene method to mitigate DARA interference.

Methods: Antibody screening and cross-matching were performed using 2-ME or DTT-based indirect antiglobulin tests (IATs) and Polybrene method (with human IgG anti-E same IATs titer as DARA as positive control) on 37 samples. Most clinically important blood group antigens on RBCs were detected after treatment with 2-ME or DTT.

Results: Treating RBCs with 2-ME eliminates the DARA interference with the antibody screening or cross-matching; yet, K antigen is denatured during treatment. DARA does not interfere with antibody screening and cross-matching via Polybrene method, while 2+ agglutinations of anti-E antibody with the same titer (IATs method) as DARA could be observed in the positive controls via this method.

Conclusion: 2-ME-based IATs or Polybrene method could replace DTT-based IATs to mitigate DARA interference.
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http://dx.doi.org/10.1080/16078454.2021.1918916DOI Listing
December 2021

Lanthanide-functionalized metal-organic frameworks based ratiometric fluorescent sensor array for identification and determination of antibiotics.

Talanta 2021 Aug 31;231:122366. Epub 2021 Mar 31.

Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, Guangdong, 510515, China. Electronic address:

Antibiotics have made great contributions to the improvement of human health and life quality. However, the current abuse of antibiotics not only has a serious impact on the environment, but also endangers people's health. For this reason, the simultaneous identification and accurate determination of as many antibiotics in the environment, food and organisms as possible is critical. Herein, a ratiometric fluorescent sensor array based on Eu and Tb co-doped metal-organic frameworks (MOFs) was fabricated. Benefiting from the sensitization of the organic ligands to Eu and Tb, the reaction of MOFs with various antibiotics resulted in different responses to the ratio of fluorescent intensity at 545 nm and 616 nm (F/F). After these responses were differentiated by principal component analysis (PCA), totally eight kinds of 25 antibiotics were well distinguished with the existence of interfering substances. The proposed sensor array exhibited high accuracy (98%) for the identification of 48 unknown samples in water and outstanding quantitative ability for the mixture of antibiotics. Finally, the practicability of the sensor array for the analysis of real samples was proved. In this strategy, we have not only provided an efficient way for the comprehensive identification and determination of antibiotics, but also promised new opportunities for the development of ratiometric signal based sensor array.
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http://dx.doi.org/10.1016/j.talanta.2021.122366DOI Listing
August 2021

Nano-assembly of ursolic acid with platinum prodrug overcomes multiple deactivation pathways in platinum-resistant ovarian cancer.

Biomater Sci 2021 Jun;9(11):4110-4119

Department of Pharmacy, Shunde Hospital, Southern Medical University (The First People's Hospital of Shunde Foshan), Foshan 528300, P. R. China. and A School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, P. R. China.

As the most common cause of gynecological cancer-related deaths worldwide, ovarian cancer requires novel therapy strategies. Pt(ii)-Based antitumor drugs (e.g. cisplatin) are one of the most successful and frequently used drugs in ovarian cancer chemotherapy at present. However, drug resistance and severe side effects are the major problems in cancer treatment. Herein, the design of a reduction responsive platinum(iv) (Pt(iv))/ursolic acid (UA)/polyethylene glycol (PEG) dual prodrug amphiphile (Pt(iv)-UA-PEG) to treat cisplatin-resistant ovarian cancer is reported for the first time. Pt(iv)-UA-PEG could self-assemble into nanoparticles (Pt(iv)-UA NPs) with a fixed and precise Pt/UA ratio, and a constantly high content of drugs. Pt(iv)-UA NPs could be efficiently taken up by cisplatin-resistant ovarian cancer cells and release the drug in intracellular reductive and acidic environments. In vitro studies show that the released UA and cisplatin have different anticancer mechanisms, and their synergistic effects overcome the detoxification and anti-apoptotic mechanisms of cancer cells. Furthermore, the in vivo results indicate that Pt(iv)-UA NPs have a prolonged blood circulation time, enhanced tumor accumulation, and significantly improved antitumor efficacy in A2780/DDP tumor-bearing mice, without causing any side effects. In summary, our results demonstrate that the development of the stimuli-responsive dual prodrug amphiphile nano-assembly provides a new strategy to overcome drug resistance.
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http://dx.doi.org/10.1039/d1bm00087jDOI Listing
June 2021
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