Publications by authors named "Hao Qi"

198 Publications

Using Artificial Neural Networks to Model Errorsin Biochemical Manipulation of DNA Molecules.

Authors:
Jiaxiang Guo Hao Qi

IEEE/ACM Trans Comput Biol Bioinform 2021 Jun 11;PP. Epub 2021 Jun 11.

In recent years, the non-biological applications of DNA molecules have made considerable progress; most of these applications were performed in vitro, involving biochemical operations such as synthesis, amplification and sequencing. Because errors may occur with specific sequence patterns or experimental instruments, these biochemical operations are not completely reliable. Modeling errors in these biochemical procedures is an interesting research topic. For example, researchers have proposed several methods to avoid the known vulnerable sequence patterns in the study of storing binary information in DNA molecules. However, there are few end-to-end methods to evaluate these biochemical errors with regard to the DNA sequences. In this article, based on the data generated by a DNA storage research, we use artificial neural networks to predict whether a DNA sequence tends to cause errors in biochemical operations. Through comparative experiments and hyperparameter optimization, we analyze the known and potential problems in the research process. As a result, an end-to-end method to model the biochemical errors of DNA molecules in vitro through a computer system is proposed.
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http://dx.doi.org/10.1109/TCBB.2021.3088525DOI Listing
June 2021

Sugar phosphate activation of the stress sensor eIF2B.

Nat Commun 2021 06 8;12(1):3440. Epub 2021 Jun 8.

Calico Life Sciences LLC, South San Francisco, CA, USA.

The multi-subunit translation initiation factor eIF2B is a control node for protein synthesis. eIF2B activity is canonically modulated through stress-responsive phosphorylation of its substrate eIF2. The eIF2B regulatory subcomplex is evolutionarily related to sugar-metabolizing enzymes, but the biological relevance of this relationship was unknown. To identify natural ligands that might regulate eIF2B, we conduct unbiased binding- and activity-based screens followed by structural studies. We find that sugar phosphates occupy the ancestral catalytic site in the eIF2Bα subunit, promote eIF2B holoenzyme formation and enhance enzymatic activity towards eIF2. A mutant in the eIF2Bα ligand pocket that causes Vanishing White Matter disease fails to engage and is not stimulated by sugar phosphates. These data underscore the importance of allosteric metabolite modulation for proper eIF2B function. We propose that eIF2B evolved to couple nutrient status via sugar phosphate sensing with the rate of protein synthesis, one of the most energetically costly cellular processes.
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http://dx.doi.org/10.1038/s41467-021-23836-zDOI Listing
June 2021

Galectin-9 and PSMB8 overexpression predict unfavorable prognosis in patients with AML.

J Cancer 2021 19;12(14):4257-4263. Epub 2021 May 19.

Department of Hematology, Aerospace Center Hospital, Peking University Aerospace School of Clinical Medicine, Beijing 100049, China.

Acute myeloid leukemia (AML) is a deadly heterogeneous hematologic malignancy. Despite the well-characterized genetic characteristics and new promising targeted therapies for AML, the clinical outcome remains suboptimal. Galectin-9 (Gal-9) is a good potential target due to its immunosuppressive capacity in inflammatory processes. In our study, we firstly performed a wide range of integrated bioinformatical approach to assess the importance of Gal-9 by analyzing the expression, potential function and prognostic impact in AML. The results indicated that Gal-9 is overexpressed in AML cells, especially when relapse after hematopoietic stem cell transplantation (HSCT) and predicts poor prognosis. Co-expression analysis showed Gal-9 has a strong positive correlation with proteasome subunit beta type-8 (PSMB8), which was also highly expressed in AML with poor prognosis, implying a synergy in cell survival, cell signaling and the development of AML. In summary, we have confirmed the overexpression of Gal-9 and its partner PSMB8 in AML and validated their importance as prognostic factors. We propose that Gal-9 and PSMB8 could be a promising molecular target for treatment of AML and may provide more combined treatment options, especially in patients with relapse after HSCT.
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http://dx.doi.org/10.7150/jca.53686DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8176406PMC
May 2021

Up-regulation of long non-coding RNA CYTOR induced by icariin promotes the viability and inhibits the apoptosis of chondrocytes.

BMC Complement Med Ther 2021 May 26;21(1):152. Epub 2021 May 26.

Department of Law, Southwest Medical University, Xianglin Road Section 1 No.1, Longmatan District, Luzhou, 646100, Sichuan, China.

Background: Icariin (ICAR) is the main effective component extracted from epimedium, and is reported to have the potential to treat osteoarthritis (OA). However, its pharmacological function on chondrocytes has not been fully clarified.

Methods: Different doses of ICAR were used to treat chondrocyte cell lines, including CHON-001 and ATDC5. Then the expressions of different lncRNAs were measured by qRT-PCR. Interleukin-1β (IL-1β) was used to simulate the inflammatory response environment of chondrocytes. Overexpression plasmids and short hairpin RNAs of lncRNA CYTOR were used to construct gain-of-function and loss of function models. CCK-8 was conducted to determine the cell viability. Flow cytometry was used to detect the apoptosis of chondrocytes. Enzyme-linked immunosorbent assay (ELISA) was adopted to measure the contents of inflammatory factors (IL-6, IL-8, TNF-α) in the supernatant of the chondrocytes.

Results: Compared with other lncRNAs, CYTOR was changed most significantly in both CHON-001 and ATDC5 cells after treatment with ICAR. ICAR promotes the viability and inhibits the apoptosis of CHON-001 and ATDC5 cells induced by IL-1β, accompanied with reduced levels of inflammatory factors. Overexpression of CYTOR facilitated the viability of chondrocytes, while repressed their apoptosis and inflammatory response. What's more, knockdown of CYTOR reversed the protective effects of ICAR on chondrocytes.

Conclusion: CYTOR was a pivotal lncRNA involved in the protective function of ICAR on chondrocytes.
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http://dx.doi.org/10.1186/s12906-021-03322-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8157716PMC
May 2021

Role of CD44 in increasing the potency of mesenchymal stem cell extracellular vesicles by hyaluronic acid in severe pneumonia.

Stem Cell Res Ther 2021 May 20;12(1):293. Epub 2021 May 20.

Department of Anesthesiology, University of California, San Francisco, 505 Parnassus Ave., Box 0648, San Francisco, CA, USA.

Background: Although promising, clinical translation of human mesenchymal stem or stromal cell-derived extracellular vesicles (MSC EV) for acute lung injury is potentially limited by significant production costs. The current study was performed to determine whether pretreatment of MSC EV with high molecular weight hyaluronic acid (HMW HA) would increase the therapeutic potency of MSC EV in severe bacterial pneumonia.

Methods: In vitro experiments were performed to determine the binding affinity of HMW HA to MSC EV and its uptake by human monocytes, and whether HMW HA primed MSC EV would increase bacterial phagocytosis by the monocytes. In addition, the role of CD44 receptor on MSC EV in the therapeutic effects of HMW HA primed MSC EV were investigated. In Pseudomonas aeruginosa (PA) pneumonia in mice, MSC EV primed with or without HMW HA were instilled intravenously 4 h after injury. After 24 h, the bronchoalveolar lavage fluid, blood, and lungs were analyzed for levels of bacteria, inflammation, MSC EV trafficking, and lung pathology.

Results: MSC EV bound preferentially to HMW HA at a molecular weight of 1.0 MDa compared with HA with a molecular weight of 40 KDa or 1.5 MDa. HMW HA primed MSC EV further increased MSC EV uptake and bacterial phagocytosis by monocytes compared to treatment with MSC EV alone. In PA pneumonia in mice, instillation of HMW HA primed MSC EV further reduced inflammation and decreased the bacterial load by enhancing the trafficking of MSC EV to the injured alveolus. CD44 siRNA pretreatment of MSC EV prior to incubation with HMW HA eliminated its trafficking to the alveolus and therapeutic effects.

Conclusions: HMW HA primed MSC EV significantly increased the potency of MSC EV in PA pneumonia in part by enhancing the trafficking of MSC EV to the sites of inflammation via the CD44 receptor on MSC EV which was associated with increased antimicrobial activity.
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http://dx.doi.org/10.1186/s13287-021-02329-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8136222PMC
May 2021

Toward living neuroprosthetics: developing a biological brain pacemaker as a living neuromodulatory implant for improving parkinsonian symptoms.

J Neural Eng 2021 Jun 8;18(4). Epub 2021 Jun 8.

Department of Electrical and Computer Engineering, The Ohio State University, Columbus, OH, United States of America.

Therapeutic intervention for Parkinson's disease (PD) via deep brain stimulation (DBS) represents the current paradigm for managing the advanced stages of the disease in patients when treatment with pharmaceuticals becomes inadequate. Although DBS is the prevailing therapy in these cases, the overall effectiveness and reliability of DBS can be diminished over time due to hardware complications and biocompatibility issues with the electronic implants. To achieve a lifetime solution, we envision that the next generation of neural implants will be entirely 'biological' and 'autologous', both physically and functionally. Thus, in this study, we set forth toward developing a biological brain pacemaker for treating PD. Our focus is to investigate engineering strategies for creating a multicellular biological circuit that integrates innate biological design and function while incorporating principles of neuromodulation to create a biological mechanism for delivering high-frequency stimulation with cellular specificity.We engineer a 3D multicellular circuit design built entirely from biological and biocompatible components using established tissue engineering protocols to demonstrate the feasibility of creating a living neural implant. Furthermore, using 2D co-culture systems, we investigate the physiologically relevant parameters that would be necessary to further develop a therapeutic benefit of high-frequency stimulation with cellular specificity within our construct design.Our results demonstrate the feasibility of fabricating a 3D multicellular circuit device in an implantable form. Furthermore, we show we can organize cellular materials to create potential functional connections in normal physiological conditions, thus laying down the foundation of designing a high-frequency pacing system for selective and controlled therapeutic neurostimulation.The findings from this study may lead to the future development of autologous living neural implants that both circumvent the issues inherent in electronic neural implants and form more biocompatible devices with lifelong robustness to repair and restore motor functions, with the ultimate benefit for patients with PD.
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http://dx.doi.org/10.1088/1741-2552/ac02ddDOI Listing
June 2021

Sensitive analysis of single nucleotide variation by Cas13d orthologs, EsCas13d and RspCas13d.

Biotechnol Bioeng 2021 May 8. Epub 2021 May 8.

School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.

RNA-guided CRISPR (RNA-targeting clustered regularly interspaced short palindromic repeats) effector Cas13d is the smallest Class II subtype VI proteins identified so far. Here, two recently identified Cas13d effectors from Eubacterium siraeum (Es) and Ruminococcus sp. (Rsp) were characterized and applied for sensitive nucleic acid detection. We demonstrated that the special target triggered collateral cleavage of these two Cas13d orthologs could provide rapid target RNA detection in picomolar range and then the tolerance for mismatch between crRNA and target RNA was characterized as well. Finally, an additional single mismatch was introduced into crRNA to enhance the two Cas13d orthologs mediated detection of low variant allele fraction, 0.1% T790M. Overall, this study demonstrated that both EsCas13d and RspCas13d could robustly detect target RNA carrying special single-nucleotide variation with high specificity and sensitivity, thereby providing newly qualified machinery in toolbox for efficient molecular diagnostics.
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http://dx.doi.org/10.1002/bit.27813DOI Listing
May 2021

Fluorescence "Turn-On" Enzyme-Responsive Supra-Amphiphile Fabricated by Host-Guest Recognition between γ-Cyclodextrin and a Tetraphenylethylene-Sodium Glycyrrhetinate Conjugate.

Langmuir 2021 05 7;37(19):6062-6068. Epub 2021 May 7.

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

A novel fluorescence "turn-on" enzyme-responsive supra-amphiphile is developed based on the host-guest recognition between γ-cyclodextrin (γ-CD) and an amphiphilic tetraphenylethene-sodium glycyrrhetinate conjugate (TPE-SGA). The covalent amphiphile TPE-SGA displayed strong fluorescence in aqueous solution owing to the aggregation-induced emission. Upon addition of γ-CD, the fluorescence of TPE-SGA was effectively turned off due to the host-guest recognition with γ-CD prohibiting the aggregation of TPE-SGA in aqueous solution. The as-formed nonfluorescent supra-amphiphile (TPE-SGA/γ-CD) inherited the α-amylase-responsive property of γ-CD. In the presence of α-amylase, the fluorescence of the supra-amphiphile was gradually turned on owing to the hydrolysis of γ-CD, and the fluorescence intensity linearly correlated to the activity of α-amylase. This study enriches the field of supra-amphiphile on the basis of cyclodextrin-based host-guest chemistry and provides a novel strategy to construct fluorescence turn-on functioned self-assemblies. It is anticipated that the fluorescence turn-on supra-amphiphile has potential applications in biological analysis and diagnosis of pancreatic diseases.
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http://dx.doi.org/10.1021/acs.langmuir.1c00781DOI Listing
May 2021

[Correlation between cold pain of knee joint and subchondral bone marrow edema in patients with knee osteoarthritis].

Zhongguo Gu Shang 2021 Feb;34(2):165-9

Department of Orthopaedics, the Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou 646000, Sichuan, China.

Objective: To investigate relationship between cold pain of knee joint and subchondral bone marrow edema (BME).

Methods: From May 2018 to August 2019, 92 patients with knee osteoarthritis (KOA) associated with cold pain of knee were admitted, all patients were underwent MRI examination. The patients were divided into observation group (47 patients with BME) and control group(45 patients without BME). In observation group, there were 6 males and 41 females aged from 36 to 87 years old with an average of (63.2±12.3) years old. In control group, there were 10 males and 35 females, aged from 48 to 84 years old with an average of (62.7±8.3) years old. All patientswere treated with drugs. The degree of joint degeneration was evaluated by Kellgren-Lawrence (K-L) grading. Degree of cold pain of knee was evaluated by knee cold pain score, and degree of BME was evaluated according to WORMS. The correlation between cold pain of knee and K-L grading and BME was analyzed.

Results: Score of cold pain in observation group (15.55±7.68) was higher than that of control group (9.42± 5.50), which had significant difference (=4.383, <0.001). There was no correlation between cold pain of knee and K-L grading(=2.138, =0.907). There was correlation between BME grading and degree of cold pain in observation group(=19.709, <0.001), and Spearman correlation coefficient was =0.509(<0.001).

Conclusion: The cold pain of KOA patients is not related to K-L grading, but corelate with BME grading. The Cold pain of knee was more pronounced in KOA patients with BME, and the severity of BME is often related to degree of cold pain. It seemed to be a tendency:the more serious BME, the heavier coldpain.
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http://dx.doi.org/10.12200/j.issn.1003-0034.2021.02.014DOI Listing
February 2021

Accurate genotyping of fragmented DNA using a toehold assisted padlock probe.

Biosens Bioelectron 2021 May 7;179:113079. Epub 2021 Feb 7.

School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, China; Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300350, China. Electronic address:

Fragmented DNA from blood plasma, i.e., cell-free DNA, has received great interest as a noninvasive diagnostic biomarker for "point-of-care" testing or liquid biopsy. Here, we present a new approach for accurate genotyping of highly fragmented DNA. Based on toehold-mediated strand displacement, a toehold-assisted padlock probe and toehold blocker were designed and demonstrated with new controllability in significantly suppressing undesired cross-reaction, promoting target recycling and point mutation detection by tuning the thermodynamic properties. Furthermore, toehold-assisted padlock probe systems were elaborately designed for 14 different single-nucleotide variants (SNVs) and were demonstrated to be able to detect low concentration of variant alleles (0.1%). In addition, a target, spanning a narrow sequence window of 29 nucleotides on average is sufficient for the toehold-assisted padlock probe system, which is valuable for the analysis of highly fragmented DNA molecules from clinical samples. We further demonstrated that the toehold-assisted padlock probe, in combination with a unique asymmetric PCR technique, could detect more target SNVs at low allele fractions (1%) in highly fragmented cfDNA. This allows accurate genotyping and provides a new commercial approach for high-resolution analysis of genetic variation.
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http://dx.doi.org/10.1016/j.bios.2021.113079DOI Listing
May 2021

Oxidative stress-mediated AMPK inactivation determines the high susceptibility of LKB1-mutant NSCLC cells to glucose starvation.

Free Radic Biol Med 2021 Apr 23;166:128-139. Epub 2021 Feb 23.

Faculty of Health Sciences, University of Macau, Taipa, Macau, China; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. Electronic address:

The liver kinase B1 (LKB1) is an important tumor suppressor and its loss-of-function mutations are observed in around 16% of non-small cell lung cancer (NSCLC) cases. One of the main functions of LKB1 is to activate AMP-activated protein kinase (AMPK) via direct phosphorylation. Under metabolic or energy stress conditions, the LKB1-AMPK axis inhibits the anabolic pathways and activates the catabolic pathways to maintain metabolic homeostasis for cell survival. In this study, we found that LKB1-mutant NSCLC cells are particularly susceptible to cell death induced by glucose starvation, but not by other forms of starvation such as amino acid starvation or serum starvation. Reconstitution of LKB1 in LKB1-mutant cells or LKB1 knockout in LKB1-wild type cells highlighted the importance of the LKB1-AMPK axis for cell survival under glucose starvation. Mechanistically, in LKB1-mutant cells, glucose starvation elicits oxidative stress, which causes AMPK protein oxidation and inactivation, and eventually cell death. Importantly, this process could be effectively reversed and rescued by 2DG (a glucose analog capable of producing NADPH, a key antioxidant), A769662 (an allosteric AMPK activator), and N-acetyl cysteine (NAC) (a ROS scavenger), indicating the presence of a vicious circle between AMPK inactivation and ROS in LKB1-mutant NSCLC cells under glucose starvation. Our study thus elucidates the critical role of redox balance in determining the susceptibility to cell death under glucose starvation in LKB1-mutant NSCLC cells. The findings from this study reveal important clues in search of novel therapeutic strategies for LKB1-mutant NSCLC by targeting glucose metabolism and redox balance.
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http://dx.doi.org/10.1016/j.freeradbiomed.2021.02.018DOI Listing
April 2021

PSD-93 mediates the crosstalk between neuron and microglia and facilitates acute ischemic stroke injury by binding to CX3CL1.

J Neurochem 2021 Feb 18. Epub 2021 Feb 18.

Department of Neurology, The Second Affiliated Hospital of Xuzhou Medical University, Xuzhou, China.

Post-synaptic density 93 (PSD-93) mediates glutamate excitotoxicity induced by ischemic brain injury, which then induces microglial inflammatory response. However, the underlying mechanisms of how PSD-93 mediates the crosstalk between neurons and microglia in the post-synaptic dense region remain elusive. CX3 chemokine ligand 1 (CX3CL1) is a chemokine specifically expressed in neurons while its receptor CX3CR1 is highly expressed in microglia. In this study, we examined the interaction of PSD-93 and CX3CL1 in the crosstalk between neurons and microglia in acute ischemic stroke. We utilized male C57BL/6 mice to establish the middle cerebral artery occlusion model (MCAO) and designed a fusion small peptide Tat-CX3CL1 (357-395aa) to inhibit PSD-93 and CX3CL1 interaction. The combination peaks of PSD-93 and CX3CL1 at 6 hr after I/R were observed. The binding sites were located at the 420-535 amino acid sequence of PSD-93 and 357-395 amino acid sequence of CX3CL1. Tat-CX3CL1 (357-395aa) could inhibit the interaction of PSD-93 and CX3CL1 and inhibited the pro-inflammatory cytokine IL-1β and TNF-α expression and provided neuroprotection following reperfusion. Together, these data suggest that PSD-93 binds CX3CL1 to activate microglia and initiate neuroinflammation. Specific blockade of PSD-93-CX3CL1 interaction reduces I/R induced neuronal cell death, and provides a new therapeutic target for ischemic stroke.
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http://dx.doi.org/10.1111/jnc.15324DOI Listing
February 2021

Precipitation of Magnetic Iron Oxide Induced by Cells.

Microorganisms 2021 Feb 7;9(2). Epub 2021 Feb 7.

School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China.

() is bacterium notable for its highly efficient urea degradation ability. Due to its high urease activity, has been successfully utilized in applications including solidifying soil or sand, termed "bio-concrete". In addition to calcium carbonate precipitation, urease isolated from the jack bean plant was recently demonstrated to induce the formation of magnetic iron oxide particles from soluble ferrous ion in a designed reaction. However, it remained unknown if a similar magnetic material could be formed using whole cells with high urease activity under biocompatible conditions. Here, we demonstrated that magnetic iron oxide with a highly ordered structure could be formed on the surface of cells with a theoretical product of 1.17 mg in a 2-mL reaction. Moreover, the cells surrounded by the precipitated magnetic iron oxide maintained their viability. Due to the simple cultivation of , the process developed in this study could be useful for the green synthesis of magnetic iron oxide, basic research on the mechanism of magnetic microbial-induced precipitation (MIP), and related engineering applications.
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http://dx.doi.org/10.3390/microorganisms9020331DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7916055PMC
February 2021

Positive lymph node ratio is an index in predicting prognosis for remnant gastric cancer with insufficient retrieved lymph node in R0 resection.

Sci Rep 2021 Jan 21;11(1):2022. Epub 2021 Jan 21.

Department of Surgical Oncology, First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, China.

The staging system of remnant gastric cancer (RGC) has not yet been established, with the current staging being based on the guidelines for primary gastric cancer. Often, surgeries for RGC fail to achieve the > 15 lymph nodes needed for TNM staging. Compared with the pN staging system, lymph node ratio (NR) may be more accurate for RGC staging and prognosis prediction. We retrospectively analyzed the data of 208 patients who underwent R0 gastrectomy with curative intent and who have ≤ 15 retrieved lymph nodes (RLNs) for RGC between 2000 and 2014. The patients were divided into four groups on the basis of the NR cutoffs: rN0: 0; rN1: > 0 and ≤ 1/6; rN2: > 1/6 and ≤ 1/2; and rN3: > 1/2. The 5-year overall survival (OS) rates for rN0, rN1, rN2, and rN3 were 84.3%, 64.7%, 31.5%, and 12.7%, respectively. Multivariable analyses revealed that tumor size (p = 0.005), lymphovascular invasion (p = 0.023), and NR (p < 0.001), but not pN stage (p = 0.682), were independent factors for OS. When the RLN count is ≤ 15, the NR is superior to pN as an important and independent prognostic index of RGC, thus predicting the prognosis of RGC patients more accurately.
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http://dx.doi.org/10.1038/s41598-021-81663-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7820341PMC
January 2021

Origin of layer-dependent SERS tunability in 2D transition metal dichalcogenides.

Nanoscale Horiz 2021 Feb 15;6(2):186-191. Epub 2021 Jan 15.

School of Physics, Southeast University, Nanjing 211189, P. R. China.

Two-dimensional (2D) semiconductors are expected to replace noble metals to become the matrix materials of the next generation of commercial surface-enhanced Raman scattering (SERS) chips. Herein, we systematically studied the influence of the interlayer interaction on the SERS activity of 2D semiconductors from a brand-new perspective and comprehensively analyzed the physicochemical process of 2D semiconductor interlayer modulated SERS. Taking transition metal dichalcogenides as examples, we chose PtSe with strong interlayer interactions and ReS with weak interlayer interactions to analyze the physicochemical process of 2D semiconductor interlayer modulated SERS by first-principles calculations. PtSe and ReS samples with various thicknesses were prepared respectively, and the results of comparative experiments proved that the layer-dependent SERS tunability of 2D semiconductors is directly related to the interlayer interaction. This work provided a novel method for further improving the SERS detection limit of 2D semiconductors and a possible strategy for the industrial upgrading of commercial SERS chips.
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http://dx.doi.org/10.1039/d0nh00625dDOI Listing
February 2021

Preparation of Alkaline Polyelectrolyte Membrane Based on Quaternary Ammonium Salt-Modified Cellulose and Its Application in Zn-Air Flexible Battery.

Polymers (Basel) 2020 Dec 22;13(1). Epub 2020 Dec 22.

Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China.

In this study, a type of alkaline solid polyelectrolyte (ASPE) membrane was developed via the introduction of microcrystalline cellulose (MCC) and its modified product (QMCC) into the polyvinyl alcohol (PVA) matrix. In this process, green NaOH/urea-based solvent was used to achieve a good dispersion of MCC in the PVA matrix; meanwhile, the OH groups in the NaOH/urea-based solvent provided an alkaline environment for good ion conductivity. Compared to the MCC-incorporated ASPE, further improved conductivity was achieved when the MCC was modified with quantitative quaternary ammonium salt. TGA showed that the addition of QMCC improved the water retention of the matrix, which was beneficial to the OH conduction in the system. Compared to the control (50 mS cm), a maximum conductivity of 238 mS cm was obtained after the incorporation of QMCC in the PVA matrix. Moreover, the tensile strength of the polymer electrolyte were also significantly increased with the addition of QMCC. Finally, this developed ASPE membrane was used in assembling a flexible Zn-air battery and showed a promising potential in the development of flexible electronic devices.
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http://dx.doi.org/10.3390/polym13010009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7792967PMC
December 2020

A neuronal wiring platform through microridges for rationally engineered neural circuits.

APL Bioeng 2020 Dec 8;4(4):046106. Epub 2020 Dec 8.

Department of Otolaryngology, The Ohio State University, Columbus, Ohio 43210, USA.

Precisely engineered neuronal circuits are promising for both fundamental research and clinical applications. However, randomly plating thousands of cells during neural network fabrication remains a major technical obstacle, which often results in a loss of tracking in neurons' identities. In this work, we demonstrated an accurate and unique neural wiring technique, mimicking neurons' natural affinity to microfibers. SU-8 microridges, imitating lie-down microfibers, were photolithographically patterned and then selectively coated with poly-l-lysine. We accurately plated neurons onto designated locations. Plated neurons were immobilized by circular microfences. Furthermore, neurites regrew effectively along the microridges and reached adjacent neurons without undesirable crosstalks. Functional chemical synapses also formed between accurately wired neurons, enabling two-way transmission of electrical signals. Finally, we fabricated microridges on a microelectrode array. Neuronal spikes, stimulation-evoked synaptic activity, and putative synaptic adaption between connected neurons were observed. This biomimetic platform is simple to fabricate and effective with neurite pathfinding. Therefore, it can serve as a powerful tool for fabricating neuronal circuits with rational design, organized cellular communications, and fast prototyping.
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http://dx.doi.org/10.1063/5.0025921DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7725535PMC
December 2020

Interlinking Primary Grains with Lithium Boron Oxide to Enhance the Stability of LiNiCoAlO.

ACS Appl Mater Interfaces 2020 Dec 14;12(51):56963-56973. Epub 2020 Dec 14.

College of Chemistry, Chemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China.

Destructive effects of surface lithium residues introduced in synthesis and degradation of the microstructure and electrode/electrolyte interface during cycling of Ni-rich cathode materials are the major problems hindering their wide application. Herein, we demonstrate an exquisite surface modification strategy that can utilize lithium residues on the surface of LiNiCoAlO to form a uniform coating layer of lithium boron oxide on the surface of the material. The resulting lithium boron oxide layer can not only efficiently serve as a protective layer to alleviate the side reactions at the electrode/electrolyte interface but also tightly interlink the primary grains of the LiNiCoAlO material to prevent the material from degradation of the microstructure. As a result, the optimized lithium boron oxide-coated LiNiCoAlO material exhibits a high initial discharge capacity of 202.1 mAh g at 0.1 C with a great capacity retention of 93.59% after 100 cycles at 2 C. Thus, the uniform lithium boron oxide coating endows the NCA material with excellent structural stability and long-term cycling capability.
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http://dx.doi.org/10.1021/acsami.0c16159DOI Listing
December 2020

NOD1/RIP2 signalling enhances the microglia-driven inflammatory response and undergoes crosstalk with inflammatory cytokines to exacerbate brain damage following intracerebral haemorrhage in mice.

J Neuroinflammation 2020 Dec 1;17(1):364. Epub 2020 Dec 1.

Institute of Nervous System Diseases and Department of Neurology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou Medical University, No. 99 West Huaihai Road, Xuzhou, 221006, Jiangsu Province, China.

Background: Secondary brain damage caused by the innate immune response and subsequent proinflammatory factor production is a major factor contributing to the high mortality of intracerebral haemorrhage (ICH). Nucleotide-binding oligomerization domain 1 (NOD1)/receptor-interacting protein 2 (RIP2) signalling has been reported to participate in the innate immune response and inflammatory response. Therefore, we investigated the role of NOD1/RIP2 signalling in mice with collagenase-induced ICH and in cultured primary microglia challenged with hemin.

Methods: Adult male C57BL/6 mice were subjected to collagenase for induction of ICH model in vivo. Cultured primary microglia and BV2 microglial cells (microglial cell line) challenged with hemin aimed to simulate the ICH model in vitro. We first defined the expression of NOD1 and RIP2 in vivo and in vitro using an ICH model by western blotting. The effect of NOD1/RIP2 signalling on ICH-induced brain injury volume, neurological deficits, brain oedema, and microglial activation were assessed following intraventricular injection of either ML130 (a NOD1 inhibitor) or GSK583 (a RIP2 inhibitor). In addition, levels of JNK/P38 MAPK, IκBα, and inflammatory factors, including tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, and inducible nitric oxide synthase (iNOS) expression, were analysed in ICH-challenged brain and hemin-exposed cultured primary microglia by western blotting. Finally, we investigated whether the inflammatory factors could undergo crosstalk with NOD1 and RIP2.

Results: The levels of NOD1 and its adaptor RIP2 were significantly elevated in the brains of mice in response to ICH and in cultured primary microglia, BV2 cells challenged with hemin. Administration of either a NOD1 or RIP2 inhibitor in mice with ICH prevented microglial activation and neuroinflammation, followed by alleviation of ICH-induced brain damage. Interestingly, the inflammatory factors interleukin (IL)-1β and tumour necrosis factor-α (TNF-α), which were enhanced by NOD1/RIP2 signalling, were found to contribute to the NOD1 and RIP2 upregulation in our study.

Conclusion: NOD1/RIP2 signalling played an important role in the regulation of the inflammatory response during ICH. In addition, a vicious feedback cycle was observed between NOD1/RIP2 and IL-1β/TNF-α, which could to some extent result in sustained brain damage during ICH. Hence, our study highlights NOD1/RIP2 signalling as a potential therapeutic target to protect the brain against secondary brain damage during ICH.
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http://dx.doi.org/10.1186/s12974-020-02015-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7708246PMC
December 2020

Flexible Surface-Enhanced Raman Scattering Chip: A Universal Platform for Real-Time Interfacial Molecular Analysis with Femtomolar Sensitivity.

ACS Appl Mater Interfaces 2020 Nov 18. Epub 2020 Nov 18.

Institute for Integrative Nanosciences, Leibniz IFW Dresden, Helmholtzstraße 20, Dresden 01069, Germany.

We propose and demonstrate a flexible surface-enhanced Raman scattering (SERS) chip as a versatile platform for femtomolar detection and real-time interfacial molecule analysis. The flexible SERS chip is composed of a flexible and transparent membrane and embedded plasmonic dimers with ultrahigh particle density and ultrasmall dimer gap. The chip enables rapid identification for residuals on solid substrates with irregular surfaces or dissolved analytes in aqueous solution. The sensitivity for liquid-state measurement is down to 0.06 molecule per dimers for 10 mol·L Rhodamine 6G molecule without molecule enrichment. Strong signal fluctuation and blinking are observed at this concentration, indicating that the detection limit is close to the single-molecule level. Meanwhile, the homogeneous liquid environment facilities accurate SERS quantification of analytes with a wide dynamic range. The synergy of flexibility and liquid-state measurement opens up avenues for the real-time study of chemical reactions. The reduction from -nitrothiophenol (PNTP) to -aminothiophenol (PATP) in the absence of the chemical reducing agents is observed at liquid interfaces by in situ SERS measurements, and the plasmon-induced hot electron is demonstrated to drive the catalytic reaction. We believe this robust and feasible approach is promising in extending the SERS technique as a general method for identifying interfacial molecular traces, tracking the evolution of heterogeneous reactions, elucidating the reaction mechanisms, and evaluating the environmental effects such as pH value and salty ions in SERS.
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http://dx.doi.org/10.1021/acsami.0c16315DOI Listing
November 2020

Low-Bias Manipulation of DNA Oligo Pool for Robust Data Storage.

ACS Synth Biol 2020 12 13;9(12):3344-3352. Epub 2020 Nov 13.

School of Chemical Engineering and Technology, Tianjin University, Tianjin 300350, P. R. China.

In DNA data storage, the massive sequence complexity creates challenges in repeatable and efficient information readout. Here, our study clearly demonstrated that PCR created significant DNA amplification biases due to its inherent mechanism of inefficient priming, product-as-template, and error-spreading prone, which greatly hinder subsequent applications such as data retrieval in DNA-based storage. To mitigate the amplification bias, we recruited an isothermal DNA amplification by combining strand displacement amplification (SDA) with magnetic beads (MB) DNA immobilization for robust, repeated, and low-bias amplification of DNA oligo pool, comprising over 100 thousand oligos, in a primer-free and low-error-spreading fashion. Furthermore, we introduced oligo pool normalization (OPN), a cost-effective and scalable method for normalizing an oligo pool, by which oligo pools comprising from 256 to 1024 distinct oligos were simply modified with improved Gini-index. Therefore, we believe that the combination of SDA and OPN can provide an ideal amplification mechanism for a low-bias copy of a large oligo pool, which is of vital importance for successful data retrieval in DNA information storage.
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http://dx.doi.org/10.1021/acssynbio.0c00419DOI Listing
December 2020

[Seasonal Chemical Composition Characteristics and Source Apportionment of PM in Zhengzhou].

Huan Jing Ke Xue 2020 Nov;41(11):4813-4824

Research Institute of Environmental Science, Zhengzhou University, Zhengzhou 450001, China.

The aim of this study was to fully understand the pollution characteristics and sources of PM in Zhengzhou, and to investigate the differences in four seasons and between urban and suburban areas. At the Zhengzhou environmental monitoring center (urban areas) and Zhengzhou University (suburban areas), 1284 environmental PM samples were collected in the four seasons of 2018. The concentrations of nine kinds of inorganic water-soluble ions, organic carbon, elemental carbon and 27 kinds of elements, were measured by ion chromatography, carbon analyzer, and X-ray fluorescence spectrometry, respectively. Enrichment factors (EF), index of geoaccumulation (), potential ecological risk index (RI), chemical mass balance model (CMB), backward trajectory, and potential source contribution function were the methods used to study the chemical component characteristics and source differences of PM in different seasons in the urban and suburban areas of Zhengzhou. The results showed that the annual average PM concentration at the Zhengzhou environmental monitoring center and Zhengzhou University sites reached (59.7±24.0) μg·m and (74.7±13.5) μg·m, respectively. The PM concentration at the suburban point was higher than at the urban point with the exception of winter, and the seasonal mean concentration decreased in the order of winter > autumn > spring > summer. Compared with the urban areas, the suburban areas were more affected by crustal substances in spring, and the concentrations of all components were higher in summer and autumn than the urban areas. Nevertheless, urban areas were more affected by coal burning sources and motor vehicle sources in winter. The component analysis results showed that the influences of soil dust and building dust were greater in the suburbs in spring than in the urban areas. In autumn, the suburbs were more affected by biomass sources than the urban areas, while the urban areas were more affected by building dust than were the suburbs. The concentrations of Cu, As, Zn, Pb, and Sb were strongly influenced by anthropogenic sources, and the enrichments of Zn, Cu, As, and Pb in urban areas were greater than in the suburbs. In addition, Zn, Cu, As, and Pb exhibited potential ecological risks. The outcomes of the CMB model showed that dust sources, secondary sulfate, secondary nitrate, and coal burning sources contributed significantly to PM concentrations in spring, summer, autumn and winter, respectively. The contributions of secondary pollution sources (secondary organic aerosol, secondary sulfate, and secondary nitrate) and motor vehicle sources to urban areas were higher than to suburban areas, and the influences of biomass sources in autumn and winter were significantly higher than in spring and summer and urban areas. The backward trajectory results indicated that the local PM concentration was affected by distant transmission from the northwest except in summer, was affected by neighboring provinces in the east in four seasons, and was affected by transmission from the south, with the exception of winter. Furthermore, the consequences of potential sources demonstrated that the local PM concentration was mainly affected by the potential areas in Henan province and its boundary with neighboring provinces.
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http://dx.doi.org/10.13227/j.hjkx.202004099DOI Listing
November 2020

Surface-Enhanced Raman Scattering Monitoring of Oxidation States in Defect-Engineered Two-Dimensional Transition Metal Dichalcogenides.

J Phys Chem Lett 2020 Oct 10;11(19):7981-7987. Epub 2020 Sep 10.

School of Physics, Southeast University, Nanjing, 211189, P.R. China.

Recent studies have found that some transition metal dichalcogenides (TMDs) with their own defects are difficult to store in the air for a long time. Worse stability of TMDs under extreme conditions has also been reported. Therefore, monitoring the oxidation and degradation processes of TMDs can directly guide the stability prediction of TMD-based devices and monitor TMDs quality. Herein, with the case of molybdenum disulfide, UV-ozone defect engineering is used to simulate the oxidation and degradation of TMDs under severe conditions. Surface-enhanced Raman scattering based on a chemical mechanism was first introduced to the dynamic monitoring of defect evolution in the oxidation and degradation of TMDs, and succeeds in tracking the TMDs oxidation state by the quantitative method. It is expected that this technology can be extended to the quantification and tracking of oxidation and degradation of other 2D materials.
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http://dx.doi.org/10.1021/acs.jpclett.0c02318DOI Listing
October 2020

Dioscin Attenuates Interleukin 1β (IL-1β)-Induced Catabolism and Apoptosis via Modulating the Toll-Like Receptor 4 (TLR4)/Nuclear Factor kappa B (NF-κB) Signaling in Human Nucleus Pulposus Cells.

Med Sci Monit 2020 Aug 25;26:e923386. Epub 2020 Aug 25.

Department of Orthopedics, The Second Affiliated Hospital of Hainan Medical University, Haikou, Hainan, China (mainland).

BACKGROUND Nucleus pulposus (NP) cell dysfunction and apoptosis contribute to disc degeneration. Dioscin, a natural steroid saponin, has been demonstrated to have anti-inflammatory, antiapoptotic, and antioxidative effects in various diseases. However, little is known about the roles of dioscin in intervertebral disc degeneration. MATERIAL AND METHODS To evaluate the roles of dioscin in disc degeneration and its specific mechanism, human NP cells were incubated with IL-1ß and various concentrations of dioscin. Cell viability, extracellular matrix protein expression, catabolic factors, degree of apoptosis, inflammatory factors, and related signaling pathways were evaluated by western blotting, fluorescence immunostaining, TUNEL staining, and reverse transcription PCR. RESULTS Dioscin inhibited IL-1ß-activated apoptotic signaling and catabolic activity in NP cells. Dioscin suppressed TLR4/NF-0kappaB signaling, and attenuated the level of inflammatory mediators (IL-6, TNF-alpha) in IL-1ß-stimulated human NP cells. CONCLUSIONS Our work provides the first evidence that dioscin attenuates IL-1ß-activated inflammation and catabolic activity in human NP cells through inhibiting the TLR4/NF-kappaB pathway, indicating that dioscin is a new potential candidate for clinical therapy to attenuate disc degeneration.
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http://dx.doi.org/10.12659/MSM.923386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7466834PMC
August 2020

Carbon tubes from biomass with prominent adsorption performance for paraquat.

Chemosphere 2021 Jan 1;262:127797. Epub 2020 Aug 1.

Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Key Laboratory of Food Nutrition and Safety, College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology, Tianjin, 300457, China; Tianjin Key Laboratory of Food Science and Health, School of Medicine, Nankai University, Tianjin, 300071, China. Electronic address:

Paraquat (PQ) pollution has become an increasing seriously threat to the ecological environment. Thus, it is vital to study novel adsorption materials capable of removing PQ. Modified carbon tubes (MCT-600) were prepared by carbonizing the seed hair fibers of Metaplexis japonica at 600 °C and further modifying with nitric acid. The MCT-600 was found to possess a regular morphology, a good graphitization degree and an abundance of carboxyl functional groups. Moreover, this materil exhibits excellent adsorption performance for paraquat (PQ), such as a fast adsorption rate (adsorption equilibrium within 20 min), large adsorption capacity (218.61 mg g) and good regeneration ability (reused more than 5 times). The adsorption process for PQ onto MCT-600 was found to be well matched to a Langmuir isotherm and pseudo-second-order kinetics model. Owing to its unique surface properties, green raw material source and simple preparation process, MCT-600 shows potential as an outstanding candidate for PQ removal from water.
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http://dx.doi.org/10.1016/j.chemosphere.2020.127797DOI Listing
January 2021

Emerging Methods for Efficient and Extensive Incorporation of Non-canonical Amino Acids Using Cell-Free Systems.

Front Bioeng Biotechnol 2020 22;8:863. Epub 2020 Jul 22.

School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.

Cell-free protein synthesis (CFPS) has emerged as a novel protein expression platform. Especially the incorporation of non-canonical amino acids (ncAAs) has led to the development of numerous flexible methods for efficient and extensive expression of artificial proteins. Approaches were developed to eliminate the endogenous competition for ncAAs and engineer translation factors, which significantly enhanced the incorporation efficiency. Furthermore, aminoacylation methods can be conveniently combined with cell-free systems, extensively expanding the available ncAAs with novel and unique moieties. In this review, we summarize the recent progresses on the efficient and extensive incorporation of ncAAs by different strategies based on the elimination of competition by endogenous factors, translation factors engineering and extensive incorporation of novel ncAAs coupled with aminoacylation methods in CFPS. We also aim to offer new ideas to researchers working on ncAA incorporation techniques in CFPS and applications in various emerging fields.
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http://dx.doi.org/10.3389/fbioe.2020.00863DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7387428PMC
July 2020

A mixed culture of bacterial cells enables an economic DNA storage on a large scale.

Commun Biol 2020 07 31;3(1):416. Epub 2020 Jul 31.

School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.

DNA emerged as a novel potential material for mass data storage, offering the possibility to cheaply solve a great data storage problem. Large oligonucleotide pools demonstrated high potential of large-scale data storage in test tube, meanwhile, living cell with high fidelity in information replication. Here we show a mixed culture of bacterial cells carrying a large oligo pool that was assembled in a high-copy-number plasmid was presented as a stable material for large-scale data storage. The underlying principle was explored by deep bioinformatic analysis. Although homology assembly showed sequence context dependent bias, the large oligonucleotide pools in the mixed culture were constant over multiple successive passages. Finally, over ten thousand distinct oligos encompassing 2304 Kbps encoding 445 KB digital data, were stored in cells, the largest storage in living cells reported so far and present a previously unreported approach for bridging the gap between in vitro and in vivo systems.
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http://dx.doi.org/10.1038/s42003-020-01141-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7395121PMC
July 2020

Clinical outcomes of revision with retrograde intermedullary nailing for failed plating of distal femoral fractures: a retrospective study.

Int Orthop 2020 11 11;44(11):2437-2442. Epub 2020 Jul 11.

Department of Orthopaedics, Traditional Chinese Medicine Hospital, Southwest Medical University, 182# Chunhui Road, Luzhou, 646000, Sichuan, People's Republic of China.

Purpose: To assess the feasibility and effectiveness of retrograde intramedullary nail (RIN) revision surgeries for locking compression plate (LCP) failure in distal femoral fractures.

Methods: This retrospective study included 13 patients who suffered from metalwork failures after they initially underwent open reduction and LCP fixation. In patients who eventually underwent RIN revision from January 2014 to December 2016, range of motion (ROM) and Hospital for Special Surgery (HSS) scores obtained before surgery and at the final follow-up time were analysed.

Results: The average operative time was 155 minutes (range, 120-210 minutes), and the average blood loss volume was 650 ml (range, 200-1350 ml). There were two cases of complications (15.38%): one was calf muscle vein thrombosis, and the other was a superficial infection. No deep tissue infection or deep vein thrombosis was observed post-operatively. The average follow-up time was 16 months (range, 12-24 months). All fractures healed in a mean of 6.5 months (range, 4-12 months), and one patient underwent an additional bone graft surgery that did not involve a bone graft during the RIN revision operation (this eventually healed at 12 months post-operatively). The mean ROM before the operation was 86.92 ± 12.34°. At the final follow-up, the mean ROM was 112.69 ± 9.27°. There was a significant difference between pre-operative and post-operative ROM (P < 0.01). The mean HSS score improved significantly from 38.85 ± 9.62 points pre-operatively to 79.62 ± 5.42 points post-operatively. There was a significant difference between pre-operative and post-operative HSS scores (P < 0.01).

Conclusions: RIN revision surgery achieved excellent clinical results in patients with LCP failure.
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http://dx.doi.org/10.1007/s00264-020-04621-xDOI Listing
November 2020

SIRT7 Deacetylates STRAP to Regulate p53 Activity and Stability.

Int J Mol Sci 2020 Jun 9;21(11). Epub 2020 Jun 9.

Department of Medical Genetics, Center for Medical Genetics, Peking University Health Science Center, Beijing 100191, China.

Serine-threonine kinase receptor-associated protein (STRAP) functions as a regulator of both TGF-β and p53 signaling that participates in the regulation of cell proliferation and cell death in response to various stresses. Here, we demonstrate that STRAP acetylation plays an important role in p53-mediated cell cycle arrest and apoptosis. STRAP is acetylated at lysines 147, 148, and 156 by the acetyltransferases CREB-binding protein (CBP) and that the acetylation is reversed by the deacetylase sirtuin7 (SIRT7). Hypo- or hyperacetylation mutations of STRAP at lysines 147, 148, and 156 (3KR or 3KQ) influence its activation and stabilization of p53. Moreover, following 5-fluorouracil (5-FU) treatment, STRAP is mobilized from the cytoplasm to the nucleus and promotes STRAP acetylation. Our finding on the regulation of STRAP links p53 with SIRT7 influencing p53 activity and stability.
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http://dx.doi.org/10.3390/ijms21114122DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7312009PMC
June 2020

Hotspots on the Move: Active Molecular Enrichment by Hierarchically Structured Micromotors for Ultrasensitive SERS Sensing.

ACS Appl Mater Interfaces 2020 Jun 10;12(25):28783-28791. Epub 2020 Jun 10.

School of Physics, Southeast University, Nanjing 211189, China.

Surface-enhanced Raman scattering (SERS) is recognized as one of the most sensitive spectroscopic tools for chemical and biological detections. Hotspots engineering has expedited promotion of SERS performance over the past few decades. Recently, molecular enrichment has proven to be another effective approach to improve the SERS performance. In this work, we propose a concept of "motile hotspots" to realize ultrasensitive SERS sensing by combining hotspots engineering and active molecular enrichment. High-density plasmonic nanostructure-supporting hotspots are assembled on the tubular outer wall of micromotors via nanoimprint and rolling origami techniques. The dense hotspots carried on these hierarchically structured micromotors (HSMs) can be magnet-powered to actively enrich molecules in fluid. The active enrichment manner of HSMs is revealed to be effective in accelerating the process of molecular adsorption. Consequently, SERS intensity increases significantly because of more molecules being adjacent to the hotspots after active molecular enrichment. This "motile hotspots" concept provides a synergistical approach in constructing a SERS platform with high performance. Moreover, the newly developed construction method of HSMs manifests the possibility of tailoring tubular length and diameter as well as surface patterns on the outer wall of HSMs, demonstrating good flexibility in constructing customized micromotors for various applications.
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http://dx.doi.org/10.1021/acsami.0c05371DOI Listing
June 2020