Publications by authors named "Yinan Zhang"

226 Publications

Surfactant Assisted Rapid-Release Liposomal Strategies Enhance the Antitumor Efficiency of Bufalin Derivative and Reduce Cardiotoxicity.

Int J Nanomedicine 2021 25;16:3581-3598. Epub 2021 May 25.

Jiangsu Key Laboratory for Functional Substance of Chinese Medicine, Nanjing University of Chinese Medicine, Nanjing, 210023, People's Republic of China.

Background: BF211, a derivative of bufalin (BF), shows significantly improved solubility and potent antitumor efficiency compared to BF. Unfortunately, the unwanted toxicity such as cardiotoxicity caused by unspecific distribution has hindered its clinical use.

Methods: PEGylated BF211 liposomes ([email protected]) were designed and optimizely prepared based on the pre-prescription research. In vitro and in vivo cardiotoxicity was evaluated. In vivo pharmacokinetics and biodistribution of [email protected] were investigated. In vivo antitumor activity and toxicity were evaluated in HepG2 cell xenograft models. The rapid-release triggered by Poloxamer 188 (P188) was assessed in vitro and in vivo.

Results: The optimized [email protected] displayed a spherical morphology with a size of (164.6 ± 10.3) nm and a high encapsulation efficiency of (93.24 ± 2.15) %. The in vivo concentration-time curves of BF211 loaded in liposomes showed a prolonged half-life in plasma and increased tumor accumulation. No obvious abnormality in electrocardiograms was observed in guinea pigs even at 9 mg/kg. Moreover, to improve the efficient release of [email protected], a surfactant-assisted rapid-release strategy was developed, and the release-promoting mechanism was revealed by the fluorescence resonance energy transfer (FRET) and fluorescence nanoparticle tracking analysis (fl-NTA) technology. Sequential injection of [email protected] and P188 could ignite the "cold" liposomes locally in tumor regions, facilitating the burst release of BF211 and enhancing the therapeutic index.

Conclusion: Our progressive efforts that begin with preparation technology and dosage regimen enable BF211 to like a drug, providing a promising nano platform to deliver the cardiac glycosides and alleviate the side effects by decreasing unspecific biodistribution.
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http://dx.doi.org/10.2147/IJN.S313153DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8165102PMC
June 2021

Prescribing Silver Chirality with DNA Origami.

J Am Chem Soc 2021 Jun 3;143(23):8639-8646. Epub 2021 Jun 3.

School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and National Center for Translational Medicine, Shanghai Jiao Tong University, Shanghai 200240, China.

Metal nanostructures of chiral geometry interacting with light via surface plasmon resonances can produce tailorable optical activity with their structural alterations. However, bottom-up fabrication of arbitrary chiral metal nanostructures with precise size and morphology remains a synthetic challenge. Here we develop a DNA origami-enabled aqueous solution metallization strategy to prescribe the chirality of silver nanostructures in three dimensions. We find that diamine silver(I) complexes coordinate with the bases of prescribed single-stranded protruding clustered DNA (pcDNA) on DNA origami via synergetic interactions including coordination, hydrogen bonds, and ion-π interaction, which induce site-specific pcDNA condensation and local enrichment of silver precursors that lowers the activation energy for nucleation. Using tubular DNA origami-based metallization, we obtain helical silver patterns up to a micrometer in length with well-defined chirality and pitches. We further demonstrate tailorable plasmonic optical activity of metallized chiral silver nanostructures. This method opens new pathways to synthesize programmable inorganic materials with arbitrary morphology and chirality.
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http://dx.doi.org/10.1021/jacs.1c00363DOI Listing
June 2021

DNA Framework-Engineered Long-Range Electrostatic Interactions for DNA Hybridization Reactions.

Angew Chem Int Ed Engl 2021 May 14. Epub 2021 May 14.

School of Chemistry and Chemical Engineering, Frontiers Science Centre for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240, China.

Long-range electrostatic interactions beyond biomolecular interaction interfaces have not been extensively studied due to the limitation in engineering electric double layers in physiological fluids. Here we find that long-range electrostatic interactions play an essential role in kinetic modulation of DNA hybridizations. Protein and gold nanoparticles with different charges are encapsulated in tetrahedral frameworks to exert diverse electrostatic effects on site-specifically tethered single DNA strands. Using this strategy, we have successfully modulated the hybridization kinetics in both bulk solution and single molecule level. Experimental and theoretical studies reveal that long-range Coulomb interactions are the key factor for hybridization rates. This work validates the important role of long-range electrostatic forces in nucleic acid-biomacromolecule complexes, which may encourage new strategies of gene regulation, antisense therapy, and nucleic acid detection.
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http://dx.doi.org/10.1002/anie.202106010DOI Listing
May 2021

Fabry-Perot cavity enhanced three-photon luminescence of atomically thin platinum diselenide.

Nanoscale 2021 May;13(19):9031-9038

Institute of Photonic Chips, University of Shanghai for Science and Technology, Shanghai 200093, China and Centre for Artificial-Intelligence Nanophotonics, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.

Two-dimensional materials, such as transition metal dichalcogenides (TMDs), exhibit intriguing physical properties that lead to both fundamental research and technology development. The recently emerged platinum diselenide (PtSe2), as a new member of the TMDs, has attracted increasing attention because of its good air stability, large refractive index and high electron mobility. However, being atomically thin significantly hinders its interaction with light, severely limiting the spontaneous or stimulated linear and nonlinear emission. Particularly, its nonlinear up-converted emission has not been fully exploited yet. Here, we experimentally observed the distinct enhancement of nonlinear up-converted luminescence of CVD-grown PtSe2 atomic layers on a SiO2/Si substrate with the assistance of the Fabry-Perot cavity resonance. The laser irradiance dependent luminescence study reveals the three-photon process of this nonlinear emission for the first time. Compared with non-resonant excitation, the luminescence enhancement can be up to six times because of the optical interference induced local field enhancement at the excitation wavelength. Leveraging this three-photon luminescence, nonlinear optical imaging and encryption were demonstrated for exploring information security applications. These results will pave the way for integrating nonlinear optical devices with the PtSe2 2D material.
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http://dx.doi.org/10.1039/d1nr00348hDOI Listing
May 2021

Costunolide ameliorates colitis via specific inhibition of HIF1α/glycolysis-mediated Th17 differentiation.

Int Immunopharmacol 2021 Apr 28;97:107688. Epub 2021 Apr 28.

Jiangsu Key Laboratory for Functional Substances of Chinese Medicine, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China. Electronic address:

Ulcerative colitis (UC) is a chronic idiopathic inflammatory disorder of colon. Costunolide, the main active constituent of Radix Aucklandiae, has been demonstrated to possess anti-inflammatory and immunomodulation activities. The aim of this study is to investigate the effect of costunolide on UC induced by dextran sulfate sodium (DSS). Results showed that oral administration of costunolide significantly improved the disease active index (DAI), rescued the reduction of colon length, downregulated myeloperoxidase (MPO) activity, alleviated the pathological changes, and decreased the levels of proinflammatory cytokines in colons of colitis mice. Costunolide also rebalanced Th17/Treg cells in colons, mesenteric lymph nodes and spleen, as indicated by decreased percentages of Th17 cells and reduced mRNA expressions of Rorc, Il17a. Interestingly, the in vitro experiment showed that no significant change in dendritic cell maturation, mRNA expressions of Ifng, Il6 and Treg cell differentiation, but a significant decreased Th17 cell differentiation was observed upon costunolide treatment. Deeper mechanistic studies showed that costunolide triggered the prolyl hydroxylase 2 (PHD2)-triggered proline hydroxylation-ubiquitination-proteasome degradation of HIF-1α, which in turn inactivated glycolytic process in Th17 rather than Treg cells. These findings clearly suggest that inhibition of HIF-1α-mediated glycolysis by costunolide is specifically responsible for Th17 cell differentiation and subsequent alleviation of UC and sets the stage for a new perspective on immune-metabolism therapy for colitis.
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http://dx.doi.org/10.1016/j.intimp.2021.107688DOI Listing
April 2021

Didymin switches M1-like toward M2-like macrophage to ameliorate ulcerative colitis via fatty acid oxidation.

Pharmacol Res 2021 Jul 27;169:105613. Epub 2021 Apr 27.

Jiangsu Key Laboratory for Functional Substance of Chinese Medicine, Stake Key Laboratory Cultivation Base for TCM Quality and Efficacy, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, PR China. Electronic address:

Inflammatory response by different polarized macrophages has a critical role in a variety of immunological pathophysiology, such as ulcerative colitis (UC). Herein, targeting the paradigm of macrophage phenotypes by small molecular modulators may influence the disease status. In the present study, we firstly demonstrated that didymin, one of the most abundant flavonoid constituents present in the citrus fruits such as oranges and lemons, remarkably attenuated the clinical symptoms of acute and chronic colitis in mice. Mechanistic studies showed that didymin converted pro-inflammatory M1-like to anti-inflammatory M2-like macrophage phenotype, but did not alter the polarization of M2-like macrophages. Metabolic tracing studies revealed that didymin strengthened fatty acid oxidation rather than glycolysis by inducing Hadhb expression. More importantly, in vivo studies verified that promotion of Hadhb expression resulted in the conversion of M1- toward M2-like macrophages and eventually alleviated colitis. Our data highlights the potential of macrophage paradigm in UC inflammation and put forth the stage for considering didymin as a metabolism regulator in reprogramming macrophage polarization, which may serve as a promising therapeutic approach for treatment of inflammation-associated disorders.
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http://dx.doi.org/10.1016/j.phrs.2021.105613DOI Listing
July 2021

Disease-modifying therapy prescription patterns in people with multiple sclerosis by age.

Ther Adv Neurol Disord 2021 31;14:17562864211006499. Epub 2021 Mar 31.

Neurology Section, VA North Texas Health Care System, Medical Service Dallas, VA Medical Center, 4500 South Lancaster Rd, Dallas, TX 75216, USA.

Background: Disease-modifying therapies (DMTs) for multiple sclerosis (MS) are approved for their ability to reduce disease activity, namely clinical relapses and signal changes on magnetic resonance imaging (MRI). Disease activity appears age dependent. Thus, the greatest benefit would be expected in younger people with MS (PwMS) whereas benefits in the elderly are uncertain.

Methods: Real-world data were obtained from PwMS from the North American Research Committee on Multiple Sclerosis (NARCOMS) registry and the US Department of Veterans Affairs Multiple Sclerosis Surveillance Registry (MSSR).

Results: 6948 PwMS were surveyed from NARCOMS, and the MSSR had 1719 participants. In younger adult PwMS 40-years old or less, 183 (61.4%) in NARCOMS and 179 (70.5%) in the MSSR were prescribed DMTs. Among PwMS over age 60, 1575 (40.1%) in NARCOMS and 239 (36.3%) in the MSSR were prescribed DMTs. More PwMS in the age group of 31-40 ( = 0.035) and 41-50 ( = 0.001) in the MSSR were using DMTs compared with PwMS of the same age groups in NARCOMS.

Conclusion: These findings suggest that DMTs are under-utilized in the younger population and continue to be commonly prescribed in the elderly. Broader access may explain the higher prescription rate of DMTs in US veterans.
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http://dx.doi.org/10.1177/17562864211006499DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020738PMC
March 2021

Toward Smart Information Processing with Synthetic DNA Molecules.

Macromol Rapid Commun 2021 Jun 17;42(11):e2100084. Epub 2021 Apr 17.

School of Chemical Science and Engineering, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Shanghai Research Institute for Intelligent Autonomous Systems, Tongji University, Shanghai, 200092, China.

DNA, a biological macromolecule, is a naturally evolved information material. From the structural point of view, an individual DNA strand can be considered as a chain of data with its bases working as single units. For decades, due to the high biochemical stability, large information storage capacity, and high recognition specificity, DNA has been recognized as an attractive material for information processing. Especially, the chemical synthesis strategies and DNA sequencing techniques have been rapidly developed recently, further enabling encoding information with synthetic DNA molecules. Herein, recent progresses are summarized on information processing based on synthetic DNA molecules from three aspects including information storage, computation, and encryption, and proposed the challenges and future development directions.
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http://dx.doi.org/10.1002/marc.202100084DOI Listing
June 2021

Construction and Validation of a Risk-Scoring Model that Preoperatively Predicts Lymph Node Metastasis in Early Gastric Cancer Patients.

Ann Surg Oncol 2021 Mar 30. Epub 2021 Mar 30.

Department of Gastrointestinal Surgery, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital and Institute, Beijing, China.

Objective: The aim of this study was to create a risk-scoring model to preoperatively predict the incidence of lymph node metastasis (LNM) in early gastric cancer (EGC) patients to guide treatment.

Methods: To construct the risk-scoring model, we retrospectively analyzed a primary cohort of 548 EGC patients. Univariate analysis and logistic regression were performed. A risk-scoring model for predicting LNM in EGC patients was developed based on preoperative factors, and another cohort of 73 patients was then analyzed to validate the model.

Results: In the primary cohort, LNM was pathologically confirmed in 72 (13.1%) patients. In the multivariate analysis, the presence of ulceration and tumor size on gastroscopy, undifferentiated histological type, and presence of enlarged lymph nodes on computed tomography or endoscopic ultrasonography were independent risk factors for LNM. A 17-point risk-scoring model was developed to predict LNM risk. The cut-off score of the model was 8, and the area under the receiver operating characteristic curve (AUC) of the model was 0.835 [95% confidence interval (CI) 0.784-0.886]. In the validation cohort, the AUC of the model was 0.829 (95% CI 0.699-0.959).

Conclusions: We developed and validated an effective 17-point risk-scoring model that could preoperatively predict LNM for EGC patients.
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http://dx.doi.org/10.1245/s10434-021-09867-2DOI Listing
March 2021

Synthesis of Rottlerone Analogues and Evaluation of Their α-Glucosidase and DPP-4 Dual Inhibitory and Glucose Consumption-Promoting Activity.

Molecules 2021 Feb 15;26(4). Epub 2021 Feb 15.

China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, China.

Our previous study found that desmethylxanthohumol () inhibited α-glucosidase in vitro. Recently, further investigations revealed that dehydrocyclodesmethylxanthohumol () and its dimer analogue rottlerone () exhibited more potent α-glucosidase inhibitory activity than . The aim of this study was to synthesize a series of rottlerone analogues and evaluate their α-glucosidase and DPP-4 dual inhibitory activity. The results showed that compounds and irreversibly and potently inhibited α-glucosidase (IC = 0.22 and 0.12 μM) and moderately inhibited DPP-4 (IC = 23.59 and 26.19 μM), respectively. In addition, compounds and significantly promoted glucose consumption, with the activity of at 0.2 μM being comparable to that of metformin at a concentration of 1 mM.
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http://dx.doi.org/10.3390/molecules26041024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7919492PMC
February 2021

Correction to: DC-SIGN-LEF1/TCF1-miR-185 feedback loop promotes colorectal cancer invasion and metastasis.

Cell Death Differ 2021 Mar 4. Epub 2021 Mar 4.

Department of General Surgery, The Second Affiliated Hospital of Dalian Medical University, 116023, Dalian, China.

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http://dx.doi.org/10.1038/s41418-021-00736-9DOI Listing
March 2021

Perceptions of risk and adherence to care in MS patients during the COVID-19 pandemic: A cross-sectional study.

Mult Scler Relat Disord 2021 May 23;50:102856. Epub 2021 Feb 23.

Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Electronic address:

Background: The COVID-19 pandemic has raised concerns for increased risk of infection in patients with multiple sclerosis (MS) and disrupted their routine MS care. The aim of this study is to characterize the extent of MS patients' perceptions of risk and adherence to care during the pandemic.

Methods: A survey was emailed to patients from a large MS center in New York City during the local peak of the pandemic to assess perceptions of infection risk and adherence to MS care including appointments, laboratory studies, MRIs, and taking disease-modifying therapies (DMT).

Results: 529 patients from the MS center responded to the survey during two weeks in April 2020. Patients collectively showed concern about becoming infected with COVID-19 (88%) and perceived a higher infection risk due of having MS (70%) and taking DMTs (68%). Patients frequently postponed appointments (41%), laboratory studies (46%), and MRIs (41%). Noncompliance with DMTs was less common (13%). Decisions to alter usual recommendations for care were made by the patient more often than by the provider regarding adherence to appointments (68%), laboratory studies (70%), MRI (67%), and DMT (65%). Degree of concern for infection was associated with adherence to appointments (p=0.020) and laboratory studies (p=0.016) but not with adherence to MRI and DMTs. Thirty-five patients reported being tested for COVID-19, of whom fourteen reported a positive test.

Conclusion: Patients with MS were highly concerned about becoming infected during the local peak of the COVID-19 pandemic. Behaviors that deviated from originally recommended MS care were common and often self-initiated, but patients were overall compliant with continuing DMTs.
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http://dx.doi.org/10.1016/j.msard.2021.102856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7899915PMC
May 2021

Phase II trial of prophylactic hyperthermic intraperitoneal chemotherapy in patients with locally advanced gastric cancer after curative surgery.

BMC Cancer 2021 Mar 2;21(1):216. Epub 2021 Mar 2.

Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Gastrointestinal Cancer center, Peking University Cancer Hospital and Institute, Fu-Cheng Road 52#, Hai-Dian District, Beijing, 100142, China.

Background: HIPEC is an emerging procedure to treat peritoneal metastasis of gastric cancer. Data about HIPEC in locally advanced gastric cancer is scarce. The purpose of this trial is to evaluate the safety and toxicity of prophylactic HIPEC with cisplatin for patients with locally advanced gastric cancer.

Methods: From March 2015 to November 2016, a prospective, randomized phase II trial was conducted. After radical gastrectomy, patients in the experimental group underwent HIPEC with cisplatin followed by adjuvant chemotherapy with SOX regime. Patients in the other group were treated with SOX regime alone. Postoperative complications and patient survival were compared.

Results: In total, 50 patients were eligible for analyses. No significant difference was found in the incidence of postoperative complications including anastomotic/intestinal leakage, liver dysfunction, bone marrow suppression, wound infection and ileus (P > 0.05). Mean duration of hospitalization after radical gastrectomy was 11.7 days. 12.2 days in experimental group and 10.8 days in control group respectively (P = 0.255). The percentage of patients with elevated tumor markers was 12.1% in experimental group, which was significantly lower than 41.2% in control group (P = 0.02). 3-year RFS of patients who treated with or without prophylactic HIPEC were 84.8 and 88.2% respectively (P = 0.986). In the multivariate analysis, pathological T stage was the only independent risk factor for the RFS of patients (P = 0.012, HR =15.071).

Conclusion: Additional intraoperative HIPEC with cisplatin did not increase postoperative complications for locally advanced gastric cancer after curative surgery. Prophylactic HIPEC with cisplatin was safe and tolerable, while it did not reduce the risk of peritoneal recurrence in this trial, supporting further studies to validate the efficacy of it.

Trial Registration: Chinese Clinical Trial Registry, ChiCTR2000038331. Registered 18 September 2020 - Retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=59692 .
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http://dx.doi.org/10.1186/s12885-021-07925-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7923597PMC
March 2021

CircAGAP1 promotes tumor progression by sponging miR-15-5p in clear cell renal cell carcinoma.

J Exp Clin Cancer Res 2021 Feb 22;40(1):76. Epub 2021 Feb 22.

Department of Medical Imaging, Tongji Hospital, Tongji University School of Medicine, Xincun Road No. 389, Shanghai, China.

Background: Accumulating evidence has revealed that circular RNAs (circRNAs), as novel noncoding RNAs, play critical roles in carcinogenesis and tumor progression. However, the functions and molecular mechanisms of circRNAs in clear cell renal cell carcinoma (ccRCC) are largely unknown.

Methods: The expression and functions of circAGAP1 were identified in clinical samples, ccRCC cells and in vivo animal models. The molecular mechanism of circAGAP1 was investigated by fluorescence in situ hybridization, RNA immunoprecipitation and luciferase assays.

Results: circAGAP1 (circ0058792) expression was significantly upregulated in ccRCC tissues compared to adjacent nontumor tissues. Moreover, the expression of circAGAP1 was closely related to the tumor size, nuclear grade and clinical stage of ccRCC in patients. Mechanistic studies demonstrated that cytoplasmic circAGAP1 targeted miR-15-5p in an RNA-induced silencing complex. Additionally, miR-15-5p expression was downregulated in ccRCC. Luciferase reporter assays showed that E2F transcription factor 3 (E2F3) was a target of miR-15-5p, and upregulated E2F3 expression was positively correlated with circAGAP1 in ccRCC. Furthermore, the tumor-promoting functions of circAGAP1 could be alleviated by miR-15-5p mimics in vitro and in vivo.

Conclusion: Our results clarify that circAGAP1 exerts its oncogenic functions as a competitive endogenous RNA (ceRNA) by sponging miR-15-5p, which promotes E2F3 expression. Targeting circAGAP1 might be a new attractive therapeutic strategy in ccRCC.
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http://dx.doi.org/10.1186/s13046-021-01864-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901094PMC
February 2021

Aging and efficacy of disease-modifying therapies in multiple sclerosis: a meta-analysis of clinical trials.

Ther Adv Neurol Disord 2020 28;13:1756286420969016. Epub 2020 Oct 28.

Neurology Section, VA North Texas Health Care System, Medical Service, 4500 South Lancaster Rd., Dallas, TX 75216, USA.

Background: Disease-modifying therapies (DMTs) for multiple sclerosis (MS) are approved for the treatment of disease activity and are effective in reducing relapses and new magnetic resonance imaging (MRI) lesions. However, disease activity generally subsides with time, and age-dependent changes in DMT efficacy are not well-established. We aimed to investigate whether age impacts the efficacy of DMTs in treating disease activity in patients with relapsing-remitting MS (RRMS).

Methods: DMT efficacy related to age was assessed through a meta-analysis of clinical trials that evaluated the efficacy of DMTs in RRMS patients as measured by reductions in the annualized relapse rate (ARR), new T2 lesions, and gadolinium-enhanced lesions on MRI. Using the mean baseline patient age from each trial, a weighted linear regression was fitted to determine whether age was associated with treatment efficacy on a group level.

Results: Group-level data from a total of 28,082 patients from 26 trials of 14 different DMTs were included in the meta-analysis. There were no statistically significant associations between age and reductions in ARR, new T2 lesions, and gadolinium-enhanced lesions of the treatment group compared with placebo.

Conclusion: DMTs for RRMS show efficacy in treating disease activity independent of age as demonstrated by group-level data from DMT clinical trials. Nevertheless, clinical trials select for patients with baseline disease activity regardless of age, thereby not representing real-world patients with RRMS, where disease activity declines with age.
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http://dx.doi.org/10.1177/1756286420969016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7838219PMC
October 2020

The Scale, Collections, and Biospecimen Distribution of Grade A Tertiary Hospital Biobanks in China: A National Survey.

Front Med (Lausanne) 2020 18;7:560600. Epub 2021 Jan 18.

Department of Endocrinology, Shanghai Fourth People's Hospital Affiliated to Tongji University, Shanghai, China.

Chinese clinical biobanks were built rapidly in grade A tertiary hospitals. However, the general information of biorepositories in China remained largely unknown. The aim of this study was to investigate the size, collections, biospecimens distribution and other characteristics of Chinese biobanks in grade A tertiary hospitals. In 2018, we launched a national survey among biobank leaders to provide a comprehensive understanding of Chinese grade A tertiary hospital biobanks. A total of 70 biobank managers or directors completed an online questionnaire to collect information about the biorepositories. Nearly 20% of biobanks stored over one million specimens, while almost one-third of biobanks stored 50-200,000 specimens. In general, plasma and serum were the specimens most commonly stored. For the use of collections, biospecimens were most commonly applied by internal clinical departments. Further analyses revealed that the large-scale biobanks were characterized by earlier establishment, more types of specimens in storage and distribution compared with small-scale biobanks. Moreover, specimens in large-scale biobanks were more commonly used for basic research (62.86% vs. 34.29%, = 0.017) and clinical research (57.14% vs. 28.57%, = 0.016). Large-scale biobanks also had more opportunities to cooperate with domestic research institutes (34.29% vs. 5.71%, = 0.003). Our survey revealed diversity in collections, distribution and utilization of biospecimens among Chinese grade A tertiary hospital biobanks. Although the biobanks had relatively large collections, the underutilization of stored biospecimens and lack of sharing could hamper clinical and biological research.
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http://dx.doi.org/10.3389/fmed.2020.560600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7848138PMC
January 2021

SMARCC1 expression is positively correlated with pathological grade and good prognosis in renal cell carcinoma.

Transl Androl Urol 2021 Jan;10(1):236-242

Department of Urology, Huashan Hospital, Fudan University, Shanghai, China.

Background: Renal cell carcinoma (RCC), which is derived from the renal tubular epithelium, is now the most common urological cancer. Of the four RCC subtypes, clear cell RCC (ccRCC) is the most common subtype and accounts for 75-80% of all RCC cases. SMARCC1, also known as BAF155, together with SMARCA4, SMARCA2, and SMARCB1, comprises the SWI/SNF protein family. It has been reported that the expression of SMARCC1 was correlated with some human cancers including prostate cancer, colon cancer, and pancreatic cancer. However, the mechanisms and regulatory roles of SMARCC1 in ccRCC are not well defined.

Methods: Our current study primarily investigated the expression of SMARCC1 and its clinical importance in two common histological types of ccRCC using microarrays (HKidE180Su02, MecDNA-HKidE030CS01).

Results: The results showed that the expression of SMARCC1 in ccRCC tissues was significantly decreased compared with that in corresponding para-tumor tissue (4.370±2.036 6.167±1.162, P=0.001). SMARCC1 expression was positively correlated with pathological grade (r=0.224, P=0.011). Moreover, ccRCC patients with high SMARCC1 expression had a better prognosis than those with low SMARCC1 expression (40.0% 95.2%, P=0.000) in the following sub-groups: pathological grade (III and IV), male sex (73.5% 95.3%, P=0.004), and tumor size >5 cm (62.5% 89.5%, P=0.044).

Conclusions: A further study is necessary to explain the mechanism of the occurrence and progression of ccRCC.
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http://dx.doi.org/10.21037/tau-20-935DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7844531PMC
January 2021

Caregivers' Understanding of Informed Consent in a Randomized Control Trial.

J Bioeth Inq 2021 Mar 15;18(1):141-150. Epub 2021 Jan 15.

Faculty of Dentistry, University of Otago, 310 Great King Street, Dunedin, 9016, New Zealand.

There are differences in caregivers' literacy and health literacy levels that may affect their ability to consent to children participating in clinical research trials. This study aimed to explore the effectiveness, and caregivers' understandings, of the process of informed consent that accompanied their child's participation in a dental randomized control trial (RCT). Telephone interviews were conducted with a convenience sample of ten caregivers who each had a child participating in the RCT. Pre-tested closed and open-ended questions were used, and the findings were produced from an inductive analysis of the latter and a descriptive analysis of the former. Participants had limited understanding of the purpose of the RCT and rated the readability of the consent form more highly than they rated their understanding of the research. All felt that informed consent was vital, but some caregivers had not read the consent documents. Some caregivers enrolled their child in the RCT because they trusted the researchers, and the majority wanted to improve dental care for children. The informed consent process was not always effective despite high readability of the informed consent documents. Researchers must consider the health literacy of the study group, and actively engaging with caregivers to achieve meaningful informed consent may be challenging. Future research could explore participants' perspectives of informed consent in populations with low health literacy and assess whether an underlying expectation not to comprehend health-related information may be a barrier to informed consent.
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http://dx.doi.org/10.1007/s11673-020-10085-wDOI Listing
March 2021

Palladium-Catalyzed Regiospecific and C-H Oxygenations of Polyaromatic Rings Mediated by Tunable Directing Groups.

Org Lett 2021 01 22;23(2):279-284. Epub 2020 Dec 22.

Jiangsu Key Laboratory for Functional Substances of Chinese Medicine, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China.

An efficient divergent approach of Pd-catalyzed C-H oxygenation of polyaromatic rings is described. Reversible directing groups enable regiospecific and oxygenation to readily access a wide array of polyaromatic phenols without pre- and postmanipulation of directing groups. The systematic mechanistic investigation, including deuterium-labeling experiments, palladacycle trapping, and DFT calculations, reveals that the tunable ligand-assisted C-H bond cleavage played a crucial role during the reaction process.
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http://dx.doi.org/10.1021/acs.orglett.0c03701DOI Listing
January 2021

Metabolite Triplet in Serum Improves the Diagnostic Accuracy of Prediabetes and Diabetes Screening.

J Proteome Res 2021 01 21;20(1):1005-1014. Epub 2020 Dec 21.

CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China.

Large-scale population screenings are not feasible by applying laborious oral glucose tolerance tests, but using fasting blood glucose (FPG) and glycated hemoglobin (HbA), a considerable number of diagnoses are missed. A novel marker is urgently needed to improve the diagnostic accuracy of broad-scale diabetes screening in easy-to-collect blood samples. In this study, by applying a novel knowledge-based, multistage discovery and validation strategy, we scaled down from 108 diabetes-associated metabolites to a diagnostic metabolite triplet (Met-T), namely hexose, 2-hydroxybutyric/2-hydroxyisobutyric acid, and phenylalanine. Met-T showed in two independent cohorts, each comprising healthy controls, prediabetic, and diabetic individuals, distinctly higher diagnostic sensitivities for diabetes screening than FPG alone (>79.6 vs <68%). Missed diagnoses decreased from >32% using fasting plasma glucose down to <20.4%. Combining Met-T and fasting plasma glucose further improved the diagnostic accuracy. Additionally, a positive association of Met-T with future diabetes risk was found (odds ratio: 1.41; = 1.03 × 10). The results reveal that missed prediabetes and diabetes diagnoses can be markedly reduced by applying Met-T alone or in combination with FPG and it opens perspectives for higher diagnostic accuracy in broad-scale diabetes-screening approaches using easy to collect sample materials.
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http://dx.doi.org/10.1021/acs.jproteome.0c00786DOI Listing
January 2021

Magnetic plasmon resonances in nanostructured topological insulators for strongly enhanced light-MoS interactions.

Light Sci Appl 2020 Nov 23;9(1):191. Epub 2020 Nov 23.

MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions, and Shaanxi Key Laboratory of Optical Information Technology, School of Physical Science and Technology, Northwestern Polytechnical University, 710129, Xi'an, China.

Magnetic resonances not only play crucial roles in artificial magnetic materials but also offer a promising way for light control and interaction with matter. Recently, magnetic resonance effects have attracted special attention in plasmonic systems for overcoming magnetic response saturation at high frequencies and realizing high-performance optical functionalities. As novel states of matter, topological insulators (TIs) present topologically protected conducting surfaces and insulating bulks in a broad optical range, providing new building blocks for plasmonics. However, until now, high-frequency (e.g. visible range) magnetic resonances and related applications have not been demonstrated in TI systems. Herein, we report for the first time, to our knowledge, a kind of visible range magnetic plasmon resonances (MPRs) in TI structures composed of nanofabricated SbTe nanogrooves. The experimental results show that the MPR response can be tailored by adjusting the nanogroove height, width, and pitch, which agrees well with the simulations and theoretical calculations. Moreover, we innovatively integrated monolayer MoS onto a TI nanostructure and observed strongly reinforced light-MoS interactions induced by a significant MPR-induced electric field enhancement, remarkable compared with TI-based electric plasmon resonances (EPRs). The MoS photoluminescence can be flexibly tuned by controlling the incident light polarization. These results enrich TI optical physics and applications in highly efficient optical functionalities as well as artificial magnetic materials at high frequencies.
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http://dx.doi.org/10.1038/s41377-020-00429-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7680790PMC
November 2020

Immobilization of Cu (II) via a graphene oxide-supported strategy for antibacterial reutilization with long-term efficacy.

J Hazard Mater 2021 05 17;410:124601. Epub 2020 Nov 17.

College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, People's Republic of China; Engineering Research Center of Dairy Quality and Safety Control Technology, Ministry of Education, Inner Mongolia University, Hohhot 010021, People's Republic of China. Electronic address:

The past several decades have witnessed tremendous research to discover ways for controlling heavy metal pollution, but most of the strategies do not involve reuse of the captured heavy metals. Herein, we propose a graphene oxide -based strategy for the effective removal of Cu ions from water, coupled with their reuse as an antibacterial agent. Using GO nanosheets as an adsorbent and nanosupport, the Cu ions were effectively extracted from water (>99.9%) and reduced in situ to copper nanoparticles (Cu NPs) containing both crystalline Cu and CuO. The as-captured Cu NPs showed efficient in vitro antibacterial ability against Escherichia coli, reducing the bacteria from 10 to 10 CFU mL by using mg mL Cu NPs/GO NSs for 1 h. The minimum inhibitory concentration determined to be only 16 μg mL. For practical applications, Cu recovered from wastewater could reduce bacteria by 8 log CFU in 1 h. The recovered Cu was still able to reduce the bacteria by 7 log CFU after 2 months of storage in an argon atmosphere. This strategy of extracting heavy metals and subsequently reutilizing to kill bacteria will be of great significance for environmental remediation and public healthcare.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124601DOI Listing
May 2021

Circular RNA microarray expression profile and potential function of circ0005875 in clear cell renal cell carcinoma.

J Cancer 2020 18;11(24):7146-7156. Epub 2020 Oct 18.

Department of Medical Imaging, Tongji Hospital, Tongji University School of Medicine, Xincun road No. 389, Shanghai, China.

Circular RNAs (circRNAs), a novel class of endogenous noncoding RNAs, are involved in a variety of diseases, including several types of cancers. We hypothesized that circRNAs are involved in the tumorigenesis and development of clear cell renal cell carcinoma (ccRCC). : To verify our hypothesis, we explored the circRNA expression profiles in 4 pairs of ccRCC tissues and their adjacent non-carcinoma tissues via microarray analysis. Selected circRNAs were further validated by qPCR. Moreover, hsa_circ_0005875 was selected for further study and the potential clinical values of hsa_circ_0005875 were investigated in 60 pairs of ccRCC tissues and adjacent normal controls. In addition, the role of hsa_circ_0005875 in ccRCC progression were performed using colony formation assay, Transwell assay and Martrigel-Transwell assay respectively. Finally, interactions between the circRNAs and miRNAs were predicted using Arraystar's miRNA target prediction software. Luciferase reporter assays were performed to evaluate the interaction between hsa_circ_0005875 and hsa_miR-145-5p. The microarray data showed 1988 circRNAs were significantly dysregulated circRNAs, including 1033 upregulated and 955 downregulated ones in the ccRCC tissues. Hsa_circ_0005875 was confirmed to be significantly upregulated in the ccRCC tumor tissues and renal carcinoma cells. Further analysis revealed that hsa_circ_0005875 expression was associated with tumor size, pathological TNM stage, histological differentiation, and lymphatic metastasis. Functional experiments demonstrated that overexpression of hsa_circ_0005875 increased proliferation, migration and invasion abilities. Moreover, bioinformatics analysis and luciferase reporter assays suggest that hsa_circ_0005875 may serve as a ceRNA (competing endogenous RNA) of miR-145-5p to relieve the repressive effect of miR-145-5p on target ZEB2. These data indicate that hsa_circ_0005875 might play a role in promoting tumor growth and metastasis and be a potential biomarker of ccRCC.
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http://dx.doi.org/10.7150/jca.48770DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7646169PMC
October 2020

Mithramycin 2'-Oximes with Improved Selectivity, Pharmacokinetics, and Ewing Sarcoma Antitumor Efficacy.

J Med Chem 2020 11 16;63(22):14067-14086. Epub 2020 Nov 16.

Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40536, United States.

Mithramycin A (MTM) inhibits the oncogenic transcription factor EWS-FLI1 in Ewing sarcoma, but poor pharmacokinetics (PK) and toxicity limit its clinical use. To address this limitation, we report an efficient MTM 2'-oxime (MTM) conjugation strategy for rapid MTM diversification. Comparative cytotoxicity assays of 41 MTM analogues using E-twenty-six (ETS) fusion-dependent and ETS fusion-independent cancer cell lines revealed improved ETS fusion-independent/dependent selectivity indices for select 2'-conjugated analogues as compared to MTM. Luciferase-based reporter assays demonstrated target engagement at low nM concentrations, and molecular assays revealed that analogues inhibit the transcriptional activity of EWS-FLI1. These in vitro screens identified (a Phe-Trp dipeptide-based 2'-conjugate) for in vivo testing. Relative to MTM, displayed an 11-fold increase in plasma exposure and improved efficacy in an Ewing sarcoma xenograft. Importantly, these studies are the first to point to simple C3 aliphatic side-chain modification of MTM as an effective strategy to improve PK.
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http://dx.doi.org/10.1021/acs.jmedchem.0c01526DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7810150PMC
November 2020

Populus euphratica annexin1 facilitates cadmium enrichment in transgenic Arabidopsis.

J Hazard Mater 2021 03 28;405:124063. Epub 2020 Sep 28.

Beijing Advanced Innovation Center for Tree Breeding by Molecular Design, College of Biological Sciences and Technology (Box 162), Beijing Forestry University, Beijing 100083, China. Electronic address:

Phytoremediation offers a great potential for affordable remediation of heavy metal (HM)-polluted soil and water. Screening and identifying candidate genes related to HM uptake and transport is prerequisite for improvement of phytoremediation by genetic engineering. Using the cadmium (Cd)-hypersensitive Populus euphratica, an annexin encoding gene facilitating Cd enrichment was identified in this study. With a 12 h exposure to CdCl (50-100 μM), P. euphratica cells down-regulated transcripts of annexin1 (PeANN1). PeANN1 was homologue to Arabidopsis annexin1 (AtANN1) and localized mainly to the plasma membrane (PM) and cytosol. Compared with wild type and Atann1 mutant, PeANN1 overexpression in Arabidopsis resulted in a more pronounced decline in survival rate and root length after a long-term Cd stress (10 d, 50 μM), due to a higher cadmium accumulation in roots. PeANN1-transgenic roots exhibited enhanced influx conductance of Cd under cadmium shock (30 min, 50 μM) and short-term stress (12 h, 50 μM). Noteworthy, the PeANN1-facilitated Cd influx was significantly inhibited by a calcium-permeable channel (CaPC) inhibitor (GdCl) but was promoted by 1 mM HO, indicating that Cd entered root cells via radical-activated CaPCs in the PM. Therefore, PeANN1 can serve as a candidate gene for improvement of phytoremediation by genetic engineering.
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http://dx.doi.org/10.1016/j.jhazmat.2020.124063DOI Listing
March 2021

Exosomes from different cells: Characteristics, modifications, and therapeutic applications.

Eur J Med Chem 2020 Dec 11;207:112784. Epub 2020 Sep 11.

College of Biotechnology, China International Science and Technology, Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, Tianjin International Cooperation Research Centre of Food Nutrition/Safety and Medicinal Chemistry, Tianjin University of Science & Technology/Tianjin Enterprise Key Laboratory for Application Research of Hyaluronic Acid, Tianjin, 300457, China. Electronic address:

Exosomes are cystic vesicles secreted by living cells with a phospholipid bilayer membrane. Importantly, these vesicles could serve to carry lipids, proteins, genetic materials, and transmit biological information in vivo. The cell-specific proteins and genetic materials in exosomes are capable of reflecting their cell origin and physiological status. Based on the different tissues and cells (macrophage, dendritic cells, tumor cells, mesenchymal stem cells, various body fluids, and so on), exosomes exhibit different characteristics and functions. Furthermore, owing to their high delivery efficiency, biocompatibility, and multifunctional properties, exosomes are expected to become a new means of drug delivery, disease diagnosis, immunotherapy, and precise treatment. At the same time, in order to supplement or enhance the therapeutic applicability of exosomes, chemical or biological modifications can be used to broaden, change or improve their therapeutic capabilities. This review focuses on three aspects: the characteristics and original functions of exosomes secreted by different cells, the modification and transformation of exosomes, and the application of exosomes in different diseases.
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http://dx.doi.org/10.1016/j.ejmech.2020.112784DOI Listing
December 2020

Long non-coding RNA BCYRN1 exerts an oncogenic role in colorectal cancer by regulating the miR-204-3p/KRAS axis.

Cancer Cell Int 2020 14;20:453. Epub 2020 Sep 14.

Department of Chemotherapy, The Affiliated Cancer Hospital of Nanjing Medical University & Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research, No. 42 Baiziting, Nanjing, China.

Background: It has been well documented that long non-coding RNAs (lncRNAs) regulate numerous characteristics of cancer, including proliferation, migration, metastasis, apoptosis, and even metabolism. LncRNA BCYRN1 (BCYRN1) is a newly identified brain cytoplasmic lncRNA with 200 nucleotides that was discovered to be highly expressed in tumour tissues, including those of hepatocellular carcinoma, gastric cancer and lung cancer. However, the roles of BCYRN1 in colorectal cancer (CRC) remain obscure. This study was designed to reveal the role of BCYRN1 in the occurrence and progression of CRC.

Methods: RT-PCR was used to detect the expression level of BCYRN1 in tumour tissues and CRC cell lines. BCYRN1 was knocked down in CRC cells, and cell proliferation changes were evaluated by cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and Ki-67 and proliferating cell nuclear antigen (PCNA) expression assays. Cell migration and invasion changes were evaluated by wound healing, Transwell and invasion-related protein expression assays. Flow cytometry analysis was used to assess whether BCYRN1 regulates the apoptosis of CRC cells. The dual luciferase reporter gene detects the competitive binding of BCYRN1 to miR-204-3p. In vivo experiments were performed to evaluate the effect of BCYRN1 on tumour development. TargetScan analysis and dual luciferase reporter gene assays were applied to detect the target gene of miR-204-3p. Rescue experiments verified that BCYRN1 affects CRC by regulating the effect of miR-204-3p on KRAS.

Results: We found that compared with normal tissues and human intestinal epithelial cells (HIECs), CRC tumour tissues and cell lines had significantly increased BCYRN1 levels. We further determined that knockdown of BCYRN1 inhibited the proliferation, migration, and invasion and promoted the apoptosis of CRC cells. In addition, bioinformatics analysis and dual luciferase reporter assay showed that BCYRN1 served as a competitive endogenous RNA (ceRNA) to regulate the development of CRC through competitively binding to miR-204-3p. Further studies proved that overexpression of miR-204-3p reversed the effects of BCYRN1 on CRC. Next, TargetScan analysis and dual luciferase reporter assay indicated that KRAS is a target gene of miR-204-3p and is negatively regulated by miR-204-3p. A series of rescue experiments showed that BCYRN1 affected the occurrence and development of CRC by regulating the effects of miR-204-3p on KRAS. In addition, tumorigenesis experiments in a CRC mouse model confirmed that BCYRN1 downregulation effectively inhibited tumour growth.

Conclusions: Our findings suggest that BCYRN1 plays a carcinogenic role in CRC by regulating the miR-204-3p/KRAS axis.
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http://dx.doi.org/10.1186/s12935-020-01543-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7491190PMC
September 2020

The triterpenoid sapogenin (2α-OH-Protopanoxadiol) ameliorates metabolic syndrome via the intestinal FXR/GLP-1 axis through gut microbiota remodelling.

Cell Death Dis 2020 09 17;11(9):770. Epub 2020 Sep 17.

Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, P.R. China.

Gypenosides, extracts of Gynostemma yixingense, have been traditionally prescribed to improve metabolic syndrome in Asian folk and local traditional medicine hospitals. However, the mechanism of its action remains unclarified. In this work, our results indicated that chronic administration of 2α-OH-protopanoxadiol (GP2), a metabolite of gypenosides in vivo, protected mice from high-fat diet-induced obesity and improved glucose tolerance by improving intestinal L-cell function. Mechanistically, GP2 treatment inhibited the enzymatic activity of bile salt hydrolase and modulated the proportions of the gut microbiota, which led to an increase in the accumulation of tauro-β-muricholic acid (TβMCA) in the intestine. TβMCA induced GLP-1 production and secretion by reducing the transcriptional activity of nuclear receptor farnesoid X receptor (FXR). Transplantation of GP2-remodelled fecal microbiota into antibiotic-treated mice also increased the intestinal TβMCA content and improved intestinal L-cell function. These findings demonstrate that GP2 ameliorates metabolic syndrome at least partly through the intestinal FXR/GLP-1 axis via gut microbiota remodelling and also suggest that GP2 may serve as a promising oral therapeutic agent for metabolic syndrome.
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http://dx.doi.org/10.1038/s41419-020-02974-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7499306PMC
September 2020

Rhodium-catalyzed iminoiodane-mediated oxyamidation studies of 5-vinyluracil derivatives using aryl and alkyl sulfamates.

Org Biomol Chem 2020 Sep;18(37):7414-7424

China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science & Technology, Tianjin, 300457, China. and Université Paris-Saclay, Centre National de la Recherche Scientifique (CNRS), Institut de Chimie des Substances Naturelles, UPR 2301, 91198, Gif-sur-Yvette, France.

The dirhodium tetraacetate-catalyzed iminoiodane-mediated reaction of 1,3-dimethyl-5-vinyluracil with phenyl sulfamate provided a high yield of 5-(1-acetyl-2-phenylsulfamoyl)ethyluracil via regioselective nucleophilic ring opening by acetate anion of the transiently formed 5-(1,2)-N-phenylsulfonylaziridine intermediate. This 1,2-oxyamidation reaction was found to be general for a variety of aryl- and alkylsulfamates as well as for various 1,3-dialkyl-5-vinyluracil derivatives. Addition of an alcohol to the reaction mixture allowed formation of the corresponding 1-alkoxy products. A selection of the substituted uracil derivatives prepared by this procedure was evaluated for cytotoxic activities in HCT-116 and HepG2 cancer cell lines and showed either no or modest activities. Further evaluation for α-glucosidase inhibition revealed that compounds 15ca and 15da were more active than acarbose, the reference inhibitor. This methodology thus allows efficient preparation of highly functionalized uracil derivatives thereby providing a synthetic route to novel compounds with potentially useful biological activities.
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http://dx.doi.org/10.1039/d0ob01548bDOI Listing
September 2020

Atomically Thin Noble Metal Dichalcogenides for Phase-Regulated Meta-optics.

Nano Lett 2020 Nov 1;20(11):7811-7818. Epub 2020 Sep 1.

Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, People's Republic of China.

Owing to its good air stability and high refractive index, two-dimensional (2D) noble metal dichalcogenide shows intriguing potential for versatile flat optics applications. However, light field manipulation at the atomic scale is conventionally considered unattainable because the small thickness and intrinsic losses of 2D materials completely suppress both resonances and phase accumulation effects. Here, we demonstrate that losses of structured atomically thick PtSe films integrated on top of a uniform substrate can be utilized to create the spots of critical coupling, enabling singular phase behaviors with a remarkable π phase jump. This finding enables the experimental demonstration of atomically thick binary meta-optics that allows an angle-robust and high unit thickness diffraction efficiency of 0.96%/nm in visible frequencies (given its thickness of merely 4.3 nm). Our results unlock the potential of a new class of 2D flat optics for light field manipulation at an atomic thickness.
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http://dx.doi.org/10.1021/acs.nanolett.0c01805DOI Listing
November 2020