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1.
Nature ; 602(7897): 431-436, 2022 02.
Article in English | MEDLINE | ID: mdl-35173341

ABSTRACT

Marked evolution of properties with minute changes in the doping level is a hallmark of the complex chemistry that governs copper oxide superconductivity as manifested in the celebrated superconducting domes and quantum criticality taking place at precise compositions1-4. The strange-metal state, in which the resistivity varies linearly with temperature, has emerged as a central feature in the normal state of copper oxide superconductors5-9. The ubiquity of this behaviour signals an intimate link between the scattering mechanism and superconductivity10-12. However, a clear quantitative picture of the correlation has been lacking. Here we report the observation of precise quantitative scaling laws among the superconducting transition temperature (Tc), the linear-in-T scattering coefficient (A1) and the doping level (x) in electron-doped copper oxide La2-xCexCuO4 (LCCO). High-resolution characterization of epitaxial composition-spread films, which encompass the entire overdoped range of LCCO, has enabled us to systematically map its structural and transport properties with unprecedented accuracy and with increments of Δx = 0.0015. We have uncovered the relations Tc ~ (xc - x)0.5 ~ (A1□)0.5, where xc is the critical doping in which superconductivity disappears and A1□ is the coefficient of the linear resistivity per CuO2 plane. The striking similarity of the Tc versus A1□ relation among copper oxides, iron-based and organic superconductors may be an indication of a common mechanism of the strange-metal behaviour and unconventional superconductivity in these systems.

2.
Brief Bioinform ; 24(4)2023 07 20.
Article in English | MEDLINE | ID: mdl-37344167

ABSTRACT

Adverse drug events (ADEs) are common in clinical practice and can cause significant harm to patients and increase resource use. Natural language processing (NLP) has been applied to automate ADE detection, but NLP systems become less adaptable when drug entities are missing or multiple medications are specified in clinical narratives. Additionally, no Chinese-language NLP system has been developed for ADE detection due to the complexity of Chinese semantics, despite ˃10 million cases of drug-related adverse events occurring annually in China. To address these challenges, we propose DKADE, a deep learning and knowledge graph-based framework for identifying ADEs. DKADE infers missing drug entities and evaluates their correlations with ADEs by combining medication orders and existing drug knowledge. Moreover, DKADE can automatically screen for new adverse drug reactions. Experimental results show that DKADE achieves an overall F1-score value of 91.13%. Furthermore, the adaptability of DKADE is validated using real-world external clinical data. In summary, DKADE is a powerful tool for studying drug safety and automating adverse event monitoring.


Subject(s)
Deep Learning , Drug-Related Side Effects and Adverse Reactions , Humans , Pattern Recognition, Automated , Semantics , Natural Language Processing
3.
Mol Ther ; 31(9): 2734-2754, 2023 09 06.
Article in English | MEDLINE | ID: mdl-37415332

ABSTRACT

Gastrin-releasing peptide (GRP) binds to its receptor (GRP receptor [GRPR]) to regulate multiple biological processes, but the function of GRP/GRPR axis in acute kidney injury (AKI) remains unknown. In the present study, GRPR is highly expressed by tubular epithelial cells (TECs) in patients or mice with AKI, while histone deacetylase 8 may lead to the transcriptional activation of GRPR. Functionally, we uncovered that GRPR was pathogenic in AKI, as genetic deletion of GRPR was able to protect mice from cisplatin- and ischemia-induced AKI. This was further confirmed by specifically deleting the GRPR gene from TECs in GRPRFlox/Flox//KspCre mice. Mechanistically, we uncovered that GRPR was able to interact with Toll-like receptor 4 to activate STAT1 that bound the promoter of MLKL and CCL2 to induce TEC necroptosis, necroinflammation, and macrophages recruitment. This was further confirmed by overexpressing STAT1 to restore renal injury in GRPRFlox/Flox/KspCre mice. Concurrently, STAT1 induced GRP synthesis to enforce the GRP/GRPR/STAT1 positive feedback loop. Importantly, targeting GRPR by lentivirus-packaged small hairpin RNA or by treatment with a novel GRPR antagonist RH-1402 was able to inhibit cisplatin-induced AKI. In conclusion, GRPR is pathogenic in AKI and mediates AKI via the STAT1-dependent mechanism. Thus, targeting GRPR may be a novel therapeutic strategy for AKI.


Subject(s)
Acute Kidney Injury , Cisplatin , Animals , Mice , Cisplatin/adverse effects , Necroptosis , Acute Kidney Injury/metabolism , Kidney/metabolism , Inflammation/metabolism , Mice, Inbred C57BL
4.
Artif Organs ; 48(2): 130-140, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37860931

ABSTRACT

BACKGROUND: Although extracorporeal membrane oxygenation (ECMO) has been used to provide temporary support for pediatric patients suffering severe respiratory or cardiac failure since 1970, ECMO systems specifically designed for pediatric patients, particularly for long-term use, remain an unmet clinical need. We sought to develop a new pediatric ECMO system, that is, pediatric pump-lung (PPL), consisting of a unique cylinder oxygenator with an outside-in radial flow path and a centrifugal pump. METHODS: Computational fluid dynamics was used to analyze the blood fluid field for optimized biocompatible and gas exchange performances in terms of flow characteristics, hemolysis, and gas transfer efficiency. Ovine blood was used for in vitro hemolysis and gas transfer testing. RESULTS: Both the computational and experimental data showed that the pressure drop through the PPL's oxygenator is significantly low, even at a flow rate of more than 3.5 L/min. The PPL showed better hemolysis performance than a commercial ECMO circuit consisting of the Quadrox-iD pediatric oxygenator and the Rotaflow pump at a 3.5 L/min flow rate and 250 mm Hg afterload pressure. The oxygen transfer rate of the PPL can reach over 200 mL/min at a flow rate of 3.5 L/min. CONCLUSIONS: The PPL has the potential to provide adequate blood pumping and excellent respiratory support with minimal risk of hemolysis for a wide range of pediatric patients.


Subject(s)
Extracorporeal Membrane Oxygenation , Hemolysis , Humans , Child , Animals , Sheep , Hydrodynamics , Extracorporeal Membrane Oxygenation/adverse effects , Lung , Oxygenators , Equipment Design
5.
Bioorg Med Chem ; 73: 117028, 2022 11 01.
Article in English | MEDLINE | ID: mdl-36182802

ABSTRACT

Pharmacological inhibition of PI3Kδ for battling solid tumors is relatively unexplored. Given the potential synergism of concurrent PI3Kδ/HDAC6 inhibition, and the drawbacks of pioneering PI3K/HDAC dual inhibitors, we discovered a novel series of dual-targeted inhibitors via building HDAC6 potency in a PI3Kδ-selective template. SAR study culminated in the discovery of compound 59, which exhibited remarkable inhibitory activity against both PI3Kδ (IC50 = 2.3 nM) and HDAC6 (IC50 = 13 nM), along with acceptable subtype specificity. In addition to the attractive anti-proliferative activities, especially against T47D cell line (IC50 = 0.042 µM), 59 treatment dramatically ablated the tumor immune escape-related STAT3 signaling and lowered PD-L1 expression at two-digit nanomolar level, reflecting the immunomodulatory properties. Due to its subtype selectivity, it demonstrated low cytotoxicity against normal cells. This research validated the therapeutic potential of PI3Kδ/HDAC6 dual inhibitors against solid tumors, attributed to their dual roles in anti-proliferation and anticancer immunomodulation.


Subject(s)
Antineoplastic Agents , Quinazolinones , Antineoplastic Agents/pharmacology , B7-H1 Antigen , Cell Line, Tumor , Cell Proliferation , Histone Deacetylase Inhibitors/pharmacology , Phosphatidylinositol 3-Kinases/metabolism , Quinazolinones/pharmacology , Structure-Activity Relationship
6.
Bioorg Chem ; 129: 106146, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36130439

ABSTRACT

Specific HDAC6 inhibitors (HDAC6is) simultaneously harboring anti-proliferative and immunomodulatory properties may prohibit tumor progression via intrinsic and immune driven effects. Herein, built upon the structurally novel lead TFH-7, structure-activity relationship study culminated in the identification of azaflavone-capped compound 20, which exhibited comparable HDAC6 inhibitory activity (IC50 = 8.5 nM) to that of Tubastatin A, a highly selective HDAC6i, as well as favorable subtype specificity. Importantly, concurrent with its impressive anti-proliferative efficacy against several solid tumor cell lines, 20 remarkably alleviated the transduction of immune-related STAT3 signaling and attenuated the expression of immunosuppressive checkpoint PD-L1 at submicromolar concentration, highlighting the immunomodulatory properties. Moreover, consistent with its favorable subtype selectivity, 20 displayed low cytotoxicity against normal human umbilical vein endothelial cells, revealing a promising safety profile. Following the intravenous administration, it demonstrated acceptable elimination half-life and exposure in Sprague-Dawley rats. Hence, the extensive functional investigation or structural modification of 20 is valuable.


Subject(s)
Flavonoids , Histone Deacetylase Inhibitors , Animals , Rats , Humans , Histone Deacetylase 6 , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/chemistry , Flavonoids/pharmacology , Endothelial Cells/metabolism , Cell Proliferation , Rats, Sprague-Dawley , Structure-Activity Relationship
7.
Bioorg Chem ; 127: 105992, 2022 10.
Article in English | MEDLINE | ID: mdl-35785553

ABSTRACT

HDAC6 inhibitors (HDAC6is) represent an emerging therapeutic option for triggering anti-cancer immune response. In this work, a novel series of HDAC6is, derived from an in-house analog of the traditional Chinese medicine monomer Schisandrin C, were designed and synthesized for SAR study. Throughout the 29 target compounds, 24a, 24b and 24h exerted single-digit nanomolar enzymatic activity and remarkably elevated subtype selectivity compared to the clinically investigated HDAC6i Ricolinostat (Selectivity index = 3.3). In A549 tumor cells, 24h, as the representative in this series (IC50 = 7.7 nM; selectivity index = 31.4), was capable of reversing IL-6-mediated PD-L1 upregulation, highlighting its immunomodulatory capability. Importantly, unlike numerous other hydroxamate-based HDACis, 24h displayed an acceptable oral bioavailability in Sprague-Dawley rats, along with high plasma exposure, long elimination half-life and slow clearance. With the aforementioned attractive performance, 24h deserves further in vivo investigation as an immunomodulatory therapeutic agent for batting human malignance.


Subject(s)
Antineoplastic Agents , Neoplasms , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cyclooctanes , Histone Deacetylase 6 , Histone Deacetylase Inhibitors/pharmacology , Humans , Immunomodulating Agents , Lignans , Neoplasms/drug therapy , Neoplasms/pathology , Polycyclic Compounds , Rats , Rats, Sprague-Dawley , Structure-Activity Relationship
8.
J Biomech Eng ; 144(7)2022 07 01.
Article in English | MEDLINE | ID: mdl-34897372

ABSTRACT

Two-dimensional mesoscale finite element analysis (FEA) of a multilayered brain tissue was performed to calculate the damage-related average stress triaxiality and local maximum von Mises strain in the brain. The FEA was integrated with rate-dependent hyperelastic and internal state variable (ISV) models, respectively, describing the behaviors of wet and dry brain tissues. Using the finite element results, a statistical method of design of experiments (DOE) was utilized to independently screen the relative influences of seven parameters related to brain morphology (sulcal width/depth, gray matter (GM) thickness, cerebrospinal fluid (CSF) thickness and brain lobe) and loading/environment conditions (strain rate and humidity) with respect to the potential damage growth/coalescence in the brain tissue. The results of the parametric study illustrated that the GM thickness and humidity were the two most crucial parameters affecting average stress triaxiality. For the local maximum von Mises strain at the depth of brain sulci, the brain lobe/region was the most influential factor. The conclusion of this investigation gives insight for the future development and refinement of a macroscale brain damage model incorporating information from lower length scale.


Subject(s)
Brain , Head , Biomechanical Phenomena , Computer Simulation , Finite Element Analysis , Stress, Mechanical
9.
Clin Exp Pharmacol Physiol ; 48(2): 203-210, 2021 02.
Article in English | MEDLINE | ID: mdl-33090501

ABSTRACT

The coronavirus disease 2019 (COVID-19) is an epidemic disease caused by the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) and spreading throughout the world rapidly. Here we evaluated the efficacy of the Lopinavir/Ritonavir (LPV/r) and its combination with other drugs in the treatment of COVID-19. We included 170 confirmed COVID-19 patients who had been cured and discharged. Their antiviral therapies were LPV/r alone or combinations with interferon (IFN), Novaferon and Arbidol. We evaluated the medication efficacy by comparing the time of the negative nucleic acid conversion and the length of hospitalization mainly. The LPV/r + Novaferon [6.00 (4.00-8.00) and 7.50 (5.00-10.00) days] had shorter time of the negative nucleic acid conversion (P = .0036) and shorter time of hospitalization (P < .001) compared with LPV/r alone [9.00 (5.00-12.00) and 12.00 (11.00-15.00) days] and LPV/r + IFN [9.00 (7.25-11.00) and 12.00 (10.00-13.50) days]. On the contrary, LPV/r + IFN [9.00 (7.25-11.00) and 12.00 (10.00-13.50) days] had shorter time of the negative nucleic acid conversion (P = .031) and shorter time of hospitalization (P < .001) compared with LPV/r + IFN +Novaferon [10.00 (8.00-11.25) and 13.50 (11.50-17.00) days] and LPV/r + IFN +Arbidol [14.00 (9.75-19.00) and 19.50 (13.25-24.00) days]. In conclusion, the combination of LPV/r and Novaferon may have better efficacy against COVID-19. However, adding IFN based on LPV/r + Novaferon or adding Arbidol based on LPV/r + IFN may not improve the efficacy.


Subject(s)
COVID-19 Drug Treatment , Lopinavir/pharmacology , Ritonavir/pharmacology , Adult , Drug Interactions , Female , Humans , Lopinavir/therapeutic use , Male , Middle Aged , Retrospective Studies , Ritonavir/therapeutic use , Treatment Outcome
10.
PLoS Genet ; 14(8): e1007592, 2018 08.
Article in English | MEDLINE | ID: mdl-30142151

ABSTRACT

Yeast WHI2 was originally identified in a genetic screen for regulators of cell cycle arrest and later suggested to function in general stress responses. However, the function of Whi2 is unknown. Whi2 has predicted structure and sequence similarity to human KCTD family proteins, which have been implicated in several cancers and are causally associated with neurological disorders but are largely uncharacterized. The identification of conserved functions between these yeast and human proteins may provide insight into disease mechanisms. We report that yeast WHI2 is a new negative regulator of TORC1 required to suppress TORC1 activity and cell growth specifically in response to low amino acids. In contrast to current opinion, WHI2 is dispensable for TORC1 inhibition in low glucose. The only widely conserved mechanism that actively suppresses both yeast and mammalian TORC1 specifically in response to low amino acids is the conserved SEACIT/GATOR1 complex that inactivates the TORC1-activating RAG-like GTPases. Unexpectedly, Whi2 acts independently and simultaneously with these established GATOR1-like Npr2-Npr3-Iml1 and RAG-like Gtr1-Gtr2 complexes, and also acts independently of the PKA pathway. Instead, Whi2 inhibits TORC1 activity through its binding partners, protein phosphatases Psr1 and Psr2, which were previously thought to only regulate amino acid levels downstream of TORC1. Furthermore, the ability to suppress TORC1 is conserved in the SKP1/BTB/POZ domain-containing, Whi2-like human protein KCTD11 but not other KCTD family members tested.


Subject(s)
Amino Acids/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Saccharomyces cerevisiae/metabolism , Transcription Factors/metabolism , Animals , COS Cells , Chlorocebus aethiops , Gene Expression Regulation , Humans , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Monomeric GTP-Binding Proteins/genetics , Monomeric GTP-Binding Proteins/metabolism , Phosphoprotein Phosphatases/genetics , Phosphoprotein Phosphatases/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins/genetics , Transcription Factors/genetics
11.
Small ; 13(26)2017 07.
Article in English | MEDLINE | ID: mdl-28544388

ABSTRACT

The electromigration process has the potential capability to move atoms one by one when properly controlled. It is therefore an appealing tool to tune the cross section of monoatomic compounds with ultimate resolution or, in the case of polyatomic compounds, to change the stoichiometry with the same atomic precision. As demonstrated here, a combination of electromigration and anti-electromigration can be used to reversibly displace atoms with a high degree of control. This enables a fine adjustment of the superconducting properties of Al weak links, whereas in Nb the diffusion of atoms leads to a more irreversible process. In a superconductor with a complex unit cell (La2-x Cex CuO4 ), the electromigration process acts selectively on the oxygen atoms with no apparent modification of the structure. This allows to adjust the doping of this compound and switch from a superconducting to an insulating state in a nearly reversible fashion. In addition, the conditions needed to replace feedback controlled electromigration by a simpler technique of electropulsing are discussed. These findings have a direct practical application as a method to explore the dependence of the characteristic parameters on the exact oxygen content and pave the way for a reversible control of local properties of nanowires.

12.
J Biol Chem ; 289(3): 1529-39, 2014 Jan 17.
Article in English | MEDLINE | ID: mdl-24297183

ABSTRACT

Deregulation of androgen receptor (AR) splice variants has been implicated to play a role in prostate cancer development and progression. To understand their functions in prostate, we established a transgenic mouse model (AR3Tg) with targeted expression of the constitutively active and androgen-independent AR splice variant AR3 (a.k.a. AR-V7) in prostate epithelium. We found that overexpression of AR3 modulates expression of a number of tumor-promoting autocrine/paracrine growth factors (including Tgfß2 and Igf1) and expands prostatic progenitor cell population, leading to development of prostatic intraepithelial neoplasia. In addition, we showed that some epithelial-mesenchymal transition-associated genes are up-regulated in AR3Tg prostates, suggesting that AR3 may antagonize AR activity and halt the differentiation process driven by AR and androgen. This notion is supported by our observations that the number of Ck5(+)/Ck8(+) intermediate cells is increased in AR3Tg prostates after castration, and expression of AR3 transgene in these intermediate cells compromises prostate epithelium regeneration upon androgen replacement. Our results demonstrate that AR3 is a driver of prostate cancer, at least in part, through modulating multiple tumor-promoting autocrine/paracrine factors.


Subject(s)
Alternative Splicing , Autocrine Communication , Gene Expression Regulation, Neoplastic , Intercellular Signaling Peptides and Proteins/metabolism , Neoplasm Proteins/metabolism , Paracrine Communication , Prostatic Neoplasms/metabolism , Receptors, Androgen/biosynthesis , Animals , Cell Line, Tumor , Epithelial-Mesenchymal Transition/genetics , Humans , Intercellular Signaling Peptides and Proteins/genetics , Male , Mice , Mice, Transgenic , Neoplasm Proteins/genetics , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Protein Isoforms/biosynthesis , Protein Isoforms/genetics , Receptors, Androgen/genetics , Up-Regulation/genetics
13.
J Biol Chem ; 289(15): 10691-10701, 2014 Apr 11.
Article in English | MEDLINE | ID: mdl-24573672

ABSTRACT

Mitophagy receptors mediate the selective recognition and targeting of damaged mitochondria by autophagosomes. The mechanism for the regulation of these receptors remains unknown. Here, we demonstrated that a novel hypoxia-responsive microRNA, microRNA-137 (miR-137), markedly inhibits mitochondrial degradation by autophagy without affecting global autophagy. miR-137 targets the expression of two mitophagy receptors NIX and FUNDC1. Impaired mitophagy in response to hypoxia caused by miR-137 is reversed by re-expression of FUNDC1 and NIX expression vectors lacking the miR-137 recognition sites at their 3' UTR. Conversely, miR-137 also suppresses the mitophagy induced by fundc1 (CDS+3'UTR) but not fundc1 (CDS) overexpression. Finally, we found that miR-137 inhibits mitophagy by reducing the expression of the mitophagy receptor thereby leads to inadequate interaction between mitophagy receptor and LC3. Our results demonstrated the regulatory role of miRNA to mitophagy receptors and revealed a novel link between miR-137 and mitophagy.


Subject(s)
Autophagy , Membrane Proteins/metabolism , MicroRNAs/metabolism , Mitochondrial Proteins/metabolism , 3' Untranslated Regions , Animals , Cell Hypoxia , Fibroblasts/metabolism , Gene Expression Regulation , Genetic Vectors , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred C57BL , Mitochondria/metabolism , Phagosomes/metabolism
14.
Phys Chem Chem Phys ; 17(25): 16519-24, 2015 Jul 07.
Article in English | MEDLINE | ID: mdl-26051117

ABSTRACT

In this paper, the nanoscale crosslinking process of thermoset polymer is studied using all-atom molecular dynamics. Based on the crosslinking simulations, the elastic properties of typical E51/593 thermoset polymer are predicted and verified by tensile experiments within a 10% error. The proposed method reveals a reliable understanding of the nanoscale crosslinking reactions occurring in thermoset polymers. Changes in system energy and overall density distribution, as well as the quantification of bond formation, yield a better insight into thermoset crosslinking that would be difficult to obtain through experimentation. The results give us confidence in realizing the virtual design of thermosets leading to tunable properties.

15.
Phys Chem Chem Phys ; 17(16): 10871-80, 2015 Apr 28.
Article in English | MEDLINE | ID: mdl-25821030

ABSTRACT

Superhydrophobic coatings on a copper substrate are grown via electrodeposition followed by thermal annealing. The influence of the deposition potential, zinc ion concentration, deposition time, annealing temperature and annealing time on the wetting properties was systematically investigated. The coating electrodeposited at -1.35 V for 25 min and annealed at 190 °C for 60 min exhibited excellent superhydrophobicity with a contact angle as high as 170 ± 2° and a sliding angle of almost 0°. The water drop can fully bounce as a balloon when impinging such a solid surface, exhibiting excellent non-sticking properties. By adopting various characterization methods, it was demonstrated that the as-prepared superhydrophobic surfaces also exhibited properties of anticorrosion, antiabrasion, long-term stability and durability and large buoyancy force, which offer an effective strategy and promising industrial applications for fabricating superhydrophobic surfaces on various metallic materials.

16.
Anal Chim Acta ; 1297: 342372, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38438241

ABSTRACT

BACKGROUND: Suppressors with different dead volumes are required to match different suppressed ion chromatography systems. Especially for suppressed open tubular ion chromatography (SOTIC), the dead volume is a critical parameter. Both connection tubes between open tubular (OT) columns and suppressors and the dead volumes of the suppressors should be as short/small as possible to minimize peak dispersion. Suppressors with different dead volumes are required to match the various suppressed ion chromatography systems that operate at low flow rates 20-200 nL/min. RESULTS: We describe three designs of on-column capillary suppressors for SOTIC: (A) on-column electrodialytic suppressor prepared by making small cracks on the cycloolefin polymer (COP) capillary at targeted locations, (B) on-column electrodialytic suppressor built on a polyether ether ketone (PEEK) capillary by removing the wall materials at target locations, (C) on-column chemical suppressor based on a single cut on a PEEK capillary at a targeted location a single cut on a PEEK capillary at a targeted location. The on-column electrodialytic suppressors work in two different modes with suppression voltage applied in co-current and counter-current direction to the eluent flow. Because of very narrow column inner diameter (i.d.), up to several hundred volts were required to suppress the hydroxide eluent, but it was found the there was a >90% loss of analytes in the suppressor accompanied with a high noise level after on-column electrodialytic suppression. Theoretical analysis reveals that high suppression voltage significantly affects the retention of specific analytes by electromigration. Further analysis indicated that the electrodialytic on-column suppressor in co-current mode would behave totally different from traditional suppressors. The on-column chemical suppression, with minimum dead volume of 0.27 nL, provides fairly well suppression of low hydroxide eluent without analyte loss in the suppressor. In design C, an efficiency of 47000 ± 1800 plates/m for Cl-, corresponding to a peak volume of 17.9 ± 0.7 nL, was obtained when separating five anion mixture (0.5 mM each) in the 25 µm i.d. AS18 latex coated PEEK OT column with an injection of 7.3 nL. Theoretical calculation revealed that a column efficiency loss of ≤3% would result in a cylindrical chemical suppression channel and thus it is taken as the acceptable dispersion contribution originating from the on-column chemical suppressor. SIGNIFICANCE: Different on-column suppressors have been designed on OT columns with i.d.s less than 30 µm. Two electrodialytic on-column suppressor designs with eluent flow parallel to the direction of electric field were proposed and tested. The eluent flow rate, analytes' retention behavior, resistance of suppression channel, current-voltage relationship, and working principles in both co-current and counter-current were experimentally investigated and comprehensively discussed. It was found that although the on-column electrodialytic suppressions (Design A and B) are not feasible in practice, the electrodialytic on-column suppressor on co-current mode has a potential of being used as an enriching capillary column for analyte ions. Design C provides fairly well chemical suppression. Theoretical calculation indicates that the loss of column efficiency can be controlled within 3%.

17.
Int J Biol Macromol ; 269(Pt 1): 132078, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38705332

ABSTRACT

The remarkable characteristics of porous biochar have generated significant interest in various fields, such as CO2 capture and supercapacitors. The modification of aerogel-derived porous biochar through activation and heteroatomic doping can effectively enhance CO2 adsorption and improve supercapacitor performance. In this study, a novel N, B-co-doped porous biochar (NBCPB) was synthesized by carbonating and activating the N, B dual-doped cellulose aerogel. N and B atoms were doped in-situ using a modified alkali-urea method. The potassium citrate was served as both an activator and a salt template to facilitate the formation of a well-developed nanostructure. The optimized NBCPB-650-1 (where 650 corresponded to activation temperature and 1 represented mass ratio of potassium citrate activator to carbonized NBCPB-400 precursor) displayed the largest micropore volume of 0.40 cm3·g-1 and a high specific surface area of 891 m2·g-1, which contributed to an excellent CO2 adsorption capacity of 4.19 mmol·g-1 at 100 kPa and 25 °C, a high CO2/N2 selectivity, and exceptional reusability (retained >97.5 % after 10 adsorption-desorption cycles). Additionally, the NBCPB-650-1 electrode also delivered a high capacitance of 220.9 F·g-1 at 1 A·g-1. Notably, the symmetrical NBCPB-650-1 supercapacitor exhibited a high energy density of 9 Wh·kg-1 at the power density of 100 W·kg-1. This study not only presents the potential application of NBCPB-650-1 material in CO2 capture and electrochemical energy storage, but also offers a new insight into easy-to-scale production of heteroatomic-modified porous biochar.


Subject(s)
Carbon Dioxide , Cellulose , Charcoal , Electric Capacitance , Nitrogen , Carbon Dioxide/chemistry , Charcoal/chemistry , Porosity , Cellulose/chemistry , Adsorption , Nitrogen/chemistry , Gels/chemistry , Electrodes
18.
Poult Sci ; 103(6): 103751, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38652951

ABSTRACT

Infectious coryza (IC) is an acute infectious respiratory disease in chickens that is caused by Avibacterium paragallinarum (A. paragallinarum). A. paragallinarum poses a significant threat to poultry health due to its virulence and multidrug resistance. This study isolated and identified 21 A. paragallinarum isolates from Guangdong between 2022 and 2023. Biochemical tests showed that 100% of A. paragallinarum isolates fermented glucose but did not ferment alginate and galactose, and only YZ18 was nicotinamide adenine dinucleotide independent. To determine the genetic relatedness between these isolates and NCBI reference strains, whole-genome-based phylogenetic analysis was employed. In addition, analysis of the 2,000 bp-length hmtp210 gene showed that the hmtp210 gene was strongly associated with A. paragallinarum serotypes. Meanwhile, a PCR assay for serotyping A. paragallinarum was developed based on the hmtp210 gene, this assay has high sensitivity and specificity. The antimicrobial susceptibility of isolates was assessed using the disk diffusion method. The antibiotic resistance genes of isolates were analyzed using the genomic method. Phenotypic resistance to ampicillin (95.2%), streptomycin (95.2%), methotrexate-sulfamethoxazole (90.5%), and tetracycline (85.7%) was most frequent among the isolates. All of the isolates exhibited resistance to multiple drugs, and furthermore, the isolates possessed a collective total of 14 genes associated with antibiotic resistance. This study will contribute to advancing our knowledge of A. paragallinarum antibiotic resistance and provide a scientific basis for the prophylaxis and treatment of IC, and the subsequent rational design of potential clinical therapeutics.


Subject(s)
Anti-Bacterial Agents , Chickens , Poultry Diseases , Poultry Diseases/microbiology , Poultry Diseases/epidemiology , Animals , China/epidemiology , Anti-Bacterial Agents/pharmacology , Prevalence , Haemophilus Infections/veterinary , Haemophilus Infections/microbiology , Haemophilus Infections/epidemiology , Pasteurellaceae/genetics , Pasteurellaceae/drug effects , Drug Resistance, Bacterial/genetics , Phylogeny , Haemophilus paragallinarum/genetics , Haemophilus paragallinarum/drug effects , Haemophilus paragallinarum/physiology , Genome, Bacterial
19.
Int J Biol Macromol ; 267(Pt 2): 131458, 2024 May.
Article in English | MEDLINE | ID: mdl-38593899

ABSTRACT

Avian influenza virus (AIV) H7N9 diseases have been recently reported, raising concerns about a potential pandemic. Thus, there is an urgent need for effective therapeutics for AIV H7N9 infections. Herein, camelid immunization and yeast two-hybrid techniques were used to identify potent neutralizing nanobodies (Nbs) targeting the H7 subtype hemagglutinin. First, we evaluated the binding specificity and hemagglutination inhibition activity of the screened Nbs against the H7 subtype hemagglutinin. Nb-Z77, with high hemagglutination inhibition activity was selected from the screened Nbs to optimize the yeast expression conditions and construct oligomeric forms of Nb-Z77 using various ligation methods. The oligomers Nb-Z77-DiGS, Nb-Z77-TriGS, Nb-Z77-Fc and Nb-Z77-Foldon were successfully constructed and expressed. Nb-Z77-DiGS and Nb-Z77-Foldon exhibited considerably greater activity than did Nb-Z77 against H7 subtype hemagglutinin, with median effective concentrations of 384.7 and 27.33 pM and binding affinity values of 213 and 5.21 pM, respectively. Nb-Z77-DiGS and Nb-Z77-Foldon completely inhibited the hemagglutination activity of the inactivated virus H7-Re1 at the lowest concentration of 0.938 µg/mL. This study screened a strain of Nb with high hemagglutination inhibition activity and enhanced its antiviral activity through oligomerization, which may have great potential for developing effective agents for the prevention, diagnosis, and treatment of AIV H7 subtype infection.


Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus , Single-Domain Antibodies , Single-Domain Antibodies/immunology , Single-Domain Antibodies/chemistry , Animals , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Influenza A Virus, H7N9 Subtype/immunology , Humans , Hemagglutination Inhibition Tests , Influenza in Birds/immunology , Influenza in Birds/virology , Influenza in Birds/prevention & control , Antibodies, Viral/immunology , Antibodies, Neutralizing/immunology
20.
Nat Commun ; 15(1): 1895, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38429269

ABSTRACT

The formation of charge density waves is a long-standing open problem, particularly in dimensions higher than one. Various observations in the vanadium antimonides discovered recently further underpin this notion. Here, we study the Kagome metal CsV3Sb5 using polarized inelastic light scattering and density functional theory calculations. We observe a significant gap anisotropy with 2 Δ max / k B T CDW ≈ 20 , far beyond the prediction of mean-field theory. The analysis of the A1g and E2g phonons, including those emerging below TCDW, indicates strong phonon-phonon coupling, presumably mediated by a strong electron-phonon interaction. Similarly, the asymmetric Fano-type lineshape of the A1g amplitude mode suggests strong electron-phonon coupling below TCDW. The large electronic gap, the enhanced anharmonic phonon-phonon coupling, and the Fano shape of the amplitude mode combined are more supportive of a strong-coupling phonon-driven charge density wave transition than of a Fermi surface instability or an exotic mechanism in CsV3Sb5.

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