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1.
J Med Virol ; 96(5): e29664, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38727137

RESUMEN

The causative agent of coronavirus disease 2019 (COVID-19), known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread accumulatively to 240 countries and continues to evolve. To gain a comprehensive understanding of the epidemiological characteristics of imported variants in China and their correlation with global circulating variants, genomic surveillance data from 11 139 imported COVID-19 cases submitted by Chinese provincial CDC laboratories between 2021 and 2022 were analyzed. Consensus sequences underwent rigorous quality checks, followed by amino acid mutations analysis using Nextclade. Sequences with satisfactory quality control status were classified according to the Pango nomenclature. The results showed that the dominant variants in imported cases reflected the global epidemic trend. An increase in the number of imported SARS-CoV-2 lineages monitored in China in the second half of 2022, and the circulating Omicron subvariants changed from the ancestral lineages of BA.5 and BA.2 into the lineages containing key amino acid mutations of spike protein. There was significant variation in the detection of Omicron subvariants among continents (χ2 = 321.968, p < 0.001) in the second half of 2022, with four lineages (BA.2.3.7, BA.2.2, BA.5.2.7, and XBB.1.2) identified through imported surveillance mainly prevalent respectively in Taiwan, China, Hong Kong SAR, China, Russian Federation, and Singapore. These findings revealed the alterations in circulating imported variants from 2021 to 2022 in China, reflecting the higher diversity of lineages in the second half of 2022, and revealed the predominant lineages of countries or regions that are in close contacts to China, providing new insights into the global prevalence of SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , China/epidemiología , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , SARS-CoV-2/clasificación , Prevalencia , Glicoproteína de la Espiga del Coronavirus/genética , Filogenia , Mutación , Genoma Viral/genética , Variación Genética
2.
China CDC Wkly ; 6(15): 324-331, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38736991

RESUMEN

Introduction: In the first half of 2023, a global shift was observed towards the predominance of XBB variants. China faced a significant epidemic between late 2022 and early 2023 due to Omicron subvariants BA.5.2 and BF.7. This study aims to depict the evolving variant distribution among provincial-level administrative divisions (PLADs) in China and explore the factors driving the predominance of XBB replacement. Methods: Sequences from local and imported coronavirus disease 2019 (COVID-19) cases recorded between January 1 and June 30, 2023, were included. The study analyzed the changing distribution of viral variants and assessed how the prior dominance of specific variants, XBB subvariants, and imported cases influenced the prevalence of the XBB replacement variant. Results: A total of 56,486 sequences were obtained from local cases, and 8,669 sequences were from imported cases. Starting in April, there was a shift in the prevalence of XBB from imported to local cases, with varying dominance among PLADs. In PLADs previously high in BF.7, the rise of XBB was delayed. A positive correlation was found between XBB proportions in imported cases from January to March and local cases in April. The distribution pattern of XBB subvariants differed between local and imported cases within the same PLAD. No significant differences were noted in the replacement rates of XBB subvariants. Conclusions: The timing of XBB dominance differed among various PLADs in China in the first half of 2023, correlating closely with the prevalence of XBB variants among imported cases.

3.
Nat Commun ; 15(1): 4541, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38806541

RESUMEN

In nature, structural and functional materials often form programmed three-dimensional (3D) assembly to perform daily functions, inspiring researchers to engineer multifunctional 3D structures. Despite much progress, a general method to fabricate and assemble a broad range of materials into functional 3D objects remains limited. Herein, to bridge the gap, we demonstrate a freeform multimaterial assembly process (FMAP) by integrating 3D printing (fused filament fabrication (FFF), direct ink writing (DIW)) with freeform laser induction (FLI). 3D printing performs the 3D structural material assembly, while FLI fabricates the functional materials in predesigned 3D space by synergistic, programmed control. This paper showcases the versatility of FMAP in spatially fabricating various types of functional materials (metals, semiconductors) within 3D structures for applications in crossbar circuits for LED display, a strain sensor for multifunctional springs and haptic manipulators, a UV sensor, a 3D electromagnet as a magnetic encoder, capacitive sensors for human machine interface, and an integrated microfluidic reactor with a built-in Joule heater for nanomaterial synthesis. This success underscores the potential of FMAP to redefine 3D printing and FLI for programmed multimaterial assembly.

4.
ChemSusChem ; : e202400424, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682649

RESUMEN

High-performance rechargeable aluminum-sulfur batteries (RASB) have great potential for various applications owing to their high theoretical capacity, abundant sulfur resources, and good safety. Nevertheless, the practical application of RASB still faces several challenges, including the polysulfide shuttle phenomenon and low sulfur utilization efficiency. Here, we first developed a synergistic copper heterogeneous metal oxide MoO2 derived from polymolybdate-based metal-organic framework as an efficient catalyst for mitigating polysulfide diffusion. This composite enhances sulfur utilization and electrical conductivity of the cathode. DFT calculations and experimental results reveal the catalyst Cu/MoO2@C not only effectively anchors aluminum polysulfides (AlPSs) to mitigate the shuttle effect, but also significantly promotes the catalytic conversion of AlPSs on the sulfur cathode side during charging and discharging. The unique nanostructure contains abundant electrocatalytic active sites of oxide nanoparticles and Cu clusters, resulting in excellent electrochemical performance. Consequently, the established RASB exhibits an initial capacity of 875 mAh g-1 at 500 mA g-1 and maintains a capacity of 967 mAh g-1 even at a high temperature of 50 °C.

5.
Eur J Pharm Biopharm ; 197: 114218, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38367759

RESUMEN

Myocardial ischemia/reperfusion (MI/R) injury is the primary cause of postischemicheartfailure. The increased expression of Thioredoxin-interacting protein (TXNIP) has been implicated in MI/R injury, although the detailed mechanism remains incompletely understood. In the present study, we observed the up-regulation of the m6A mRNA methylation complex component Wilms' tumor 1-associating protein (WTAP) in MI/R mice, which led to the m6A modification of TXNIP mRNA and an increase in mRNA abundance. Knock-down of WTAP resulted in a significant reduction in the m6A level of TXNIP mRNA and down-regulated TXNIP expression. Moreover, exosomes engineered with ischemic myocardium-targeting peptide (IMTP) were able to deliver WTAP siRNA into ischemic myocardial tissues, resulting in a specific gene knockdown and myocardial protection. In summary, our findings demonstrate that the WTAP-TXNIP regulatory axis plays a significant role in postischemicheartfailure, and the use of engineered exosomes targeting the ischemic heart shows promise as a strategy for siRNA therapy to protect the heart from injury.


Asunto(s)
Exosomas , Daño por Reperfusión Miocárdica , Ratones , Animales , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/terapia , Daño por Reperfusión Miocárdica/metabolismo , ARN Interferente Pequeño/metabolismo , Exosomas/genética , Exosomas/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Miocardio/metabolismo , ARN Mensajero/metabolismo
6.
Acta Biomater ; 177: 165-177, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38354873

RESUMEN

Four-dimensional (4D) printing unlocks new potentials for personalized biomedical implantation, but still with hurdles of lacking suitable materials. Herein, we demonstrate a bioresorbable shape memory elastomer (SME) with high elasticity at both below and above its phase transition temperature (Ttrans). This SME can be digital light 3D printed by co-polymerizing glycerol dodecanoate acrylate prepolymer (pre-PGDA) with acrylic acid monomer to form crosslinked Poly(glycerol dodecanoate acrylate) (PGDA)-Polyacrylic acid (PAA), or PGDA-PAA network. The printed complex, free-standing 3D structures with high-resolution features exhibit shape programming properties at a physiological temperature. By tuning the pre-PGDA weight ratios between 55 wt% and 70 wt%, Ttrans varies between 39.2 and 47.2 ℃ while Young's moduli (E) range 40-170 MPa below Ttrans with fractural strain (εf) of 170 %-200 %. Above Ttrans, E drops to 1-1.82 MPa which is close to those of soft tissue. Strikingly, εf of 130-180 % is still maintained. In vitro biocompatibility test on the material shows > 90 % cell proliferation and great cell attachment. In vivo vascular grafting trials underline the geometrical and mechanical adaptability of these 4D printed constructs in regenerating the aorta tissue. Biodegradation of the implants shows the possibility of their full replacement by natural tissue over time. To highlight its potential for personalized medicine, a patient-specific left atrial appendage (LAA) occluder was printed and implanted endovascularly into an in vitro heart model. STATEMENT OF SIGNIFICANCE: 4D printed shape-memory elastomer (SME) implants particularly designed and manufactured for a patient are greatly sought-after in minimally invasive surgery (MIS). Traditional shape-memory polymers used in these implants often suffer from issues like unsuitable transition temperatures, poor biocompatibility, limited 3D design complexity, and low toughness, making them unsuitable for MIS. Our new SME, with an adjustable transition temperature and enhanced toughness, is both biocompatible and naturally degradable, particularly in cardiovascular contexts. This allows implants, like biomedical scaffolds, to be programmed at room temperature and then adapt to the body's physiological conditions post-implantation. Our studies, including in vivo vascular grafts and in vitro device implantation, highlight the SME's effectiveness in aortic tissue regeneration and its promising applications in MIS.


Asunto(s)
Elastómeros , Andamios del Tejido , Humanos , Elastómeros/química , Andamios del Tejido/química , Glicerol , Implantes Absorbibles , Lauratos , Impresión Tridimensional , Acrilatos
7.
Inflammation ; 47(2): 733-752, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38129360

RESUMEN

There is an increasing evidence indicating the involvement of the sympathetic nervous system (SNS) in liver disease development. To achieve an extensive comprehension of the obscure process by which the SNS alleviates inflammatory damage in non-parenchymal liver cells (NPCs) during acute liver failure (ALF), we employ isoproterenol (ISO), a beta-adrenoceptor agonist, to mimic SNS signaling. ISO was administered to C57BL/6J mice to establish an acute liver failure (ALF) model using LPS/D-GalN, which was defined as ISO + ALF. Non-parenchymal cells (NPCs) were isolated from liver tissues and digested for tandem mass tag (TMT) labeled proteomics to identify differentially expressed proteins (DEPs). The administration of ISO resulted in a decreased serum levels of pro-inflammatory cytokines, e.g., TNF-α, IL-1ß, and IL-6 in ALF mice, which alleviated liver damage. By using TMT analysis, it was possible to identify 1587 differentially expressed proteins (DEPs) in isolated NPCs. Notably, over 60% of the DEPs in the ISO + ALF vs. ALF comparison were shared in the Con vs. ALF comparison. According to enrichment analysis, the DEPs influenced by ISO in ALF mice were linked to biological functions of heme and fatty acid metabolism, interferon gamma response, TNFA signaling pathway, and mitochondrial oxidation function. Protein-protein interaction network analysis indicated Mapk14 and Caspase3 may serve as potentially valuable indicators of ISO intervention. In addition, the markers on activated macrophages, such as Mapk14, Casp1, Casp8, and Mrc1, were identified downregulated after ISO initiation. ISO treatment increased the abundance of anti-inflammatory markers in mouse macrophages, as evidenced by the immunohistochemistry (IHC) slides showing an increase in Arg + staining and a reduction in iNOS + staining. Furthermore, pretreatment with ISO also resulted in a reduction of LPS-stimulated inflammation signaling markers, Mapk14 and NF-κB, in human THP-1 cells. Prior treatment with ISO may have the potential to modify the biological functions of NPCs and could serve as an innovative pharmacotherapy for delaying the pathogenesis and progression of ALF.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Isoproterenol , Animales , Ratones , Agonistas Adrenérgicos beta/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Citocinas/metabolismo , Galactosamina , Isoproterenol/farmacología , Lipopolisacáridos/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Fallo Hepático Agudo/tratamiento farmacológico , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/metabolismo , Ratones Endogámicos C57BL
8.
Water Res ; 247: 120796, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37918198

RESUMEN

The sludge fermentation-driven biological nitrogen removal (SFBNR) has garnered increasing attention due to its efficient carbon resource utilization from waste activated sludge (WAS). This study successfully extended the application of this technique to a 38 m3 reactor, facilitating a daily ultra-low carbon to nitrogen ratio (<1) wastewater treatment capacity of 16 tons and a WAS capacity of 500 L. After 185-days operation, the system demonstrated commendable performance with a denitrification efficiency (DNE) of 93.22 % and a sludge reduction efficiency (SRE) of 72.07 %. To better understand the potential mechanisms, various functional bacteria interactions were revealed by co-occurrence network analysis. The results unveiled module hubs (e.g., Anaerolineaceae, Denitratisoma, and Candidatus Brocadia) and connectors (e.g., Tuaera and Candidatus Alysiosphaera) in the network exhibited synergistic relationships facilitated by carbon metabolism and nitrogen cycling. Furthermore, the interaction between biofilm sludge (BS) and suspended sludge (SS) contributed to the in-situ enrichment of anaerobic ammonium oxidizing bacteria (AnAOB), whose abundance in BS reached 1.8 % (200-times higher than in SS) after six months, and the suspend-biofilm interface served as a hotspot for anammox activity.


Asunto(s)
Compuestos de Amonio , Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , Fermentación , Proyectos Piloto , Desnitrificación , Nitrógeno/metabolismo , Reactores Biológicos/microbiología , Oxidación-Reducción , Compuestos de Amonio/metabolismo , Bacterias Anaerobias/metabolismo , Carbono
9.
Inorg Chem ; 62(38): 15440-15449, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37700509

RESUMEN

Lithium-sulfur (Li-S) batteries are considered as promising candidates for next-generation batteries due to their high theoretical energy density. However, the practical application of Li-S batteries is still hindered by several challenges, such as the polysulfide shuttle and the growth of lithium dendrites. Herein, we introduce a bifunctional K3PW12O40/graphene oxide-modified polypropylene separator (KPW/GO/PP) as a highly effective solution for mitigating polysulfide diffusion and protecting the lithium anode in Li-S batteries. By incorporating KPW into a densely stacked nanostructured graphene oxide (GO) barrier membrane, we synergistically capture and rapidly convert lithium polysulfides (LiPSs) electrochemically, thus effectively suppressing the shuttling effect. Moreover, the KPW/GO/PP separator can stabilize the lithium metal anode during cycling, suppress dendrite formation, and ensure a smooth and dense lithium metal surface, owing to regulated Li+ flux and uniform Li nucleation. Consequently, the constructed KPW/GO/PP separator delivered a favorable initial specific capacity (1006 mAh g-1) and remarkable cycling performance at 1.0 C (626 mAh g-1 for up to 500 cycles with a decay rate of 0.075% per cycle).

10.
Small ; 19(48): e2304515, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37541304

RESUMEN

Al-S battery (ASB) is a promising energy storage device, notable for its safety, crustal abundance, and high theoretical energy density. However, its development faces challenges due to slow reaction kinetics and poor reversibility. The creation of a multifunctional cathode material that can both adsorb polysulfides and accelerate their conversion is key to advancing ASB. Herein, a composite composed of polyoxometalate nanohybridization-derived Mo2 C and N-doped carbon nanotube-interwoven polyhedrons (Co/Mo2 C@NCNHP) is proposed for the first time as an electrochemical catalyst in the sulfur cathode. This composite improves the utilization and conductivity of sulfur within the cathode. DFT calculations and experimental results indicate that Co enables the chemisorption of polysulfides while Mo2 C catalyzes the reduction reaction of long-chain polysulfides. X-ray photoelectron spectroscopy (XPS) and in situ UV analysis reveal the different intermediates of Al polysulfide species in Co/Mo2 C@NCNHP during discharging/charging. As a cathode material for ASB, Co/Mo2 C@NCNHP@S composite can deliver a discharge-charge voltage hysteresis of 0.75 V with a specific capacity of 370 mAh g-1 after 200 cycles at 1A g-1 .

11.
Angew Chem Int Ed Engl ; 62(36): e202306528, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37464580

RESUMEN

Developing polyoxometalate-cyclodextrin cluster-organic supramolecular framework (POM-CD-COSF) still remains challenging due to an extremely difficult task in rationally interconnecting two dissimilar building blocks. Here we report an unprecedented POM-CD-COSF crystalline structure produced through the self-assembly process of a Krebs-type POM, [Zn2 (WO2 )2 (SbW9 O33 )2 ]10- , and two ß-CD units. The as-prepared POM-CD-COSF-based battery separator can be applied as a lightweight barrier (approximately 0.3 mg cm-2 ) to mitigate the polysulfide shuttle effect in lithium-sulfur batteries. The designed Li-S batteries equipped with the POM-CD-COSF modified separator exhibit remarkable electrochemical performance, attributed to fast Li+ diffusion through the supramolecular channel of ß-CD, efficient polysulfide-capture ability by the dynamic host-guest interaction of ß-CD, and improved sulfur redox kinetics by the bidirectional catalysis of POM cluster. This research provides a broad perspective for the development of multifunctional supramolecular POM frameworks and their applications in Li-S batteries.

12.
Polymers (Basel) ; 15(14)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37514480

RESUMEN

Nanofibers (NFs) have the advantages of tremendous flexibility, small size and a high surface-to-weight ratio and are widely used in sensors, drug carriers and filters. Patterned NFs have expanded their application fields in tissue engineering and electronics. Electrospinning (ES) is widely used to prepare nonwoven NFs by stretching polymer solution jets with electric forces. However, patterned NFs cannot be easily fabricated using ordinary ES methods: the process gradually deteriorates them as repulsion effects between the deposited NFs and the incoming ones increase while residual charges in the fibers accumulate. Repulsion effects are unavoidable because charges in the polymer solution jets are the fundamental forces that are meant to stretch the jets into NFs. TRIZ theory is an effective innovation method for resolving conflicts and eliminating contradictions. Based on the material-field model and the contradiction matrix of TRIZ theory, we propose a strategy to improve ES devices, neutralizing the charges retained in NFs by alternating the current power of the correct frequency, thus successfully fabricating patterned NFs with clear boundaries and good continuity. This study demonstrates a strategy for resolving conflicts in innovation processes based on TRIZ theory and fabricating patterned NFs for potential applications in flexible electronics and wearable sensors.

13.
Chem Eng J ; 4702023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37484781

RESUMEN

Development of reversible wet or underwater adhesives remains a grand challenge. Because weakened intermolecular interactions by water molecules or/and low effective contact area cause poor interface to the wet surfaces, which significantly decreases adhesive strength. Herein, a new photocured, bio-based shape memory polymer (SMP) that shows both chemical and structural wet adhesion to various types of surfaces is developed. The SMP is polymerized from three monomers mainly from bio-sources to form linear polymer chains dangled with hydrophobic side chains. The hydrogen acceptor and donor groups in the chains form hydrogen bonding with the surfaces, which is protected by the hydrophobic chains in the interface. The SMP shows tunable phase transition temperature (Tg) of 17-38 °C. In a rubbery state above Tg, the adhesive forms conformable contact with the targeted surfaces. Below Tg, a transition to a glassy state locks the conformed shapes to largely increase the effective contact area. As a result, the adhesive exhibits long-term underwater adhesion of > 15 days with the best adhesion strength of ~ 0.9 MPa. Its applications in leak repair, underwater on-skin sensors were demonstrated. This new, general strategy would pave avenues to designing bio-based, long-lasting, and reversible adhesives from renewable feedstocks for widespread applications.

14.
Polymers (Basel) ; 15(12)2023 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-37376279

RESUMEN

Plant fiber-reinforced composites have the advantages of environmental friendliness, sustainability, and high specific strength and modulus. They are widely used as low-carbon emission materials in automobiles, construction, and buildings. The prediction of their mechanical performance is critical for material optimal design and application. However, the variation in the physical structure of plant fibers, the randomness of meso-structures, and the multiple material parameters of composites limit the optimal design of the composite mechanical properties. Based on tensile experiments on bamboo fiber-reinforced, palm oil-based resin composites, finite element simulations were carried out and the effect of material parameters on the tensile performances of the composites was investigated. In addition, machine learning methods were used to predict the tensile properties of the composites. The numerical results showed that the resin type, contact interface, fiber volume fraction, and multi-factor coupling significantly influenced the tensile performance of the composites. The results of the machine learning analysis showed that the gradient boosting decision tree method had the best prediction performance for the tensile strength of the composites (R2 was 0.786) based on numerical simulation data from a small sample size. Furthermore, the machine learning analysis demonstrated that the resin performance and fiber volume fraction were critical parameters for the tensile strength of composites. This study provides an insightful understanding and effective route for investigating the tensile performance of complex bio-composites.

15.
Int J Biol Sci ; 19(8): 2349-2365, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37215987

RESUMEN

Long non-coding RNAs (lncRNAs) have been to regulate tumor progression and therapy resistance through various molecular mechanisms. In this study, we investigated the role of lncRNAs in nasopharyngeal carcinoma (NPC) and the underlying mechanism. Using lncRNA arrays to analyze the lncRNA profiles of the NPC and para-tumor tissues, we detected the novel lnc-MRPL39-2:1, which was validated by in situ hybridization and by the 5' and 3' rapid amplification of the cDNA ends. Further, its role in NPC cell growth and metastasis was verified in vitro and in vivo. The researchers conducted the RNA pull-down assays, mass spectrometry (MS), dual-luciferase reporter assays, RNA immunoprecipitation (RIP) assays, and the MS2-RIP assays were then used to identify the lnc-MRPL39-2:1-interacting proteins and miRNAs. We found that lnc-MRPL39-2:1, which was highly expressed in in NPC tissues, was related to a poor prognosis in NPC patients. Furthermore, lnc-MRPL39-2:1 was shown to induce the growth and invasion of NPC by interacting directly with the Hu-antigen R (HuR) to upregulate ß-catenin expression both in vivo and in vitro. Lnc-MRPL39-2:1 expression was also suppressed by microRNA (miR)-329. Thus, these findings indicate that lnc-MRPL39-2:1 is essential in NPC tumorigenesis and metastasis and highlight its potential as a prognostic marker and therapeutic target for NPC.


Asunto(s)
MicroARNs , Neoplasias Nasofaríngeas , ARN Largo no Codificante , Humanos , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero , beta Catenina/genética , beta Catenina/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , MicroARNs/metabolismo , Proliferación Celular/genética , Neoplasias Nasofaríngeas/metabolismo , Línea Celular Tumoral
16.
China CDC Wkly ; 5(7): 143-151, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-37009519

RESUMEN

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has generated 2,431 variants over the course of its global transmission over the past 3 years. To better evaluate the genomic variation of SARS-CoV-2 before and after the optimization of coronavirus disease 2019 (COVID-19) prevention and control strategies, we analyzed the genetic evolution branch composition and genomic variation of SARS-CoV-2 in both domestic and imported cases in China (the data from Hong Kong and Macau Special Administrative Regions and Taiwan, China were not included) from September 26, 2022 to January 29, 2023. Methods: Analysis of the number of genome sequences, sampling time, dynamic changes of evolutionary branches, origin, and clinical typing of SARS-CoV-2 variants submitted by 31 provincial-level administrative divisions (PLADs) and Xinjiang Production and Construction Corps (XPCC) was conducted to assess the accuracy and timeliness of SARS-CoV-2 variant surveillance. Results: From September 26, 2022 to January 29, 2023, 20,013 valid genome sequences of domestic cases were reported in China, with 72 evolutionary branches. Additionally, 1,978 valid genome sequences of imported cases were reported, with 169 evolutionary branches. The prevalence of the Omicron variants of SARS-CoV-2 in both domestic and imported cases was consistent with that of international epidemic variants. Conclusions: This study provides an overview of the prevalence of Omicron variants of SARS-CoV-2 in China. After optimizing COVID-19 prevention and control strategies, no novel Omicron variants of SARS-CoV-2 with altered biological characteristics or public health significance have been identified since December 1, 2022.

17.
Int J Biol Macromol ; 237: 124030, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36921813

RESUMEN

Lignin valorization to biobased polyphenols antioxidants is increasingly attractive in the modern industry due to their inherent phenolic structures. Herein, lignin-derived polyphenols with enhanced antioxidant activities were prepared from the most available technical lignin including organosolv lignin (OL), alkali lignin (AL), and enzyme lignin (EL) by iodocyclohexane (ICH) chemical demethylation. The structural evolution of lignin indicated that the CAr-OCH3 group and the CAr-O-Calkyl side-chain could be effectively transformed into the CAr-OH group, resulting in a significant increase of the phenolic-OH content and a slight decrease of the molecular weight. The 1,1-diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging activity was in the order of ICHOL-24 > ICHAL-24 > ICHEL-24 ≈ FA > BHT, and the IC50 value of ICHOL-24 was 0.56 times lower than that of BHT. The structure-activity relationship demonstrated the activities were quasi-linearly related to phenolic-OH contents and could be affected by molecular weights. The H/G/S proportions of lignin could be an indicator for accurate screening of efficient lignin-derived polyphenols antioxidants (LPA). It was preliminarily estimated to have economic feasibility for producing LPA from technical lignin by demethylation compared with synthetic or natural antioxidants. This work will help to develop efficient biobased antioxidants for lignin valorization.


Asunto(s)
Antioxidantes , Lignina , Antioxidantes/química , Lignina/química , Polifenoles , Relación Estructura-Actividad , Fenoles/química , Desmetilación
18.
ACS Appl Mater Interfaces ; 15(4): 5963-5973, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36650640

RESUMEN

The demands of safety and sustainability have driven the development of intrinsic flame-retardant biobased polymers from renewable materials. Herein, a mechanically robust, good flame-retardant, and recyclable thermoset was developed from renewable epoxidized soybean oil (ESO) by using 2-hydroxyethyl methacrylate phosphate (HEMAP) as the reactive flame retardant and tannic acid (TA) as the charring agent. The flame resistance of the obtained ESO-based thermoset achieved the highest UL-94 of V-0 rating and a limited oxygen index value of 26.7% due to the synergistic flame-retardant effect of phosphate and TA. The flame-retardant mechanisms of the gaseous phase and condensed phase were fully investigated by thermogravimetric infrared, scanning electron microscopy-energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and Raman spectra. It is confirmed that the incorporation of phosphate and TA could effectively promote the formation of dense carbon layers and delay the pyrolysis of long aliphatic chains. The ternary crosslinking of ESO, HEMAP, and TA via free-radical polymerization and epoxy-ring opening reaction resulted in a rigid network with a high crosslink density, bestowing the thermoset with superior tensile strength (20.0 MPa), flexural strength (36.3 MPa), and bonding strength (16.7 MPa on steel). Moreover, the ESO-based thermoset exhibited a fast stress relaxation behavior due to the transesterification of dynamic ß-hydroxyl phosphate esters, which enables the network with thermal-healing ability and recyclability. This study explores a feasible method to prepare an intrinsic flame-retardant polymer from commercially available and renewable vegetable oils and natural polyphenols.

19.
Chem Commun (Camb) ; 59(6): 788-791, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36562392

RESUMEN

A novel supramolecular complex Li3Cl[(HPW12O40)(H24C12O6)3(CH3CN)2] {CR-PW12} was confirmed first to apply as a sulfur host in lithium-sulfur batteries. The {CR-PW12}@S cathode exhibits a reversible capacity of 1120 mA h g-1 at 1.0 C and excellent cycle stability.

20.
Acta Obstet Gynecol Scand ; 101(11): 1197-1206, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36082797

RESUMEN

INTRODUCTION: Mother-to-child transmission (MTCT) of the hepatitis B virus (HBV) is a serious public health challenge. Estimating HBV MTCT incidence by region under different prophylaxis regimens is critical to understanding the regional disease burden and prioritizing interventions. This study aimed to calculate HBV MTCT incidence under different prophylaxis regimens globally and regionally and identify the HBV DNA threshold for maternal peripartum antiviral prophylaxis. MATERIAL AND METHODS: This review was registered in advance in PROSPERO (CRD 42019120567). We searched PubMed, Embase, China National Knowledge Infrastructure, ClinicalTrials.gov, and Cochrane Library databases for studies on MTCT in pregnant women with chronic HBV infection from their inception until June 13, 2022. MTCT was defined as hepatitis B surface antigen (HBsAg) or HBV DNA seropositivity in infants aged 6-12 months. We calculated the pooled HBV MTCT incidence using the DerSimonian-Laird random-effects model. RESULTS: Among 300 studies, 3402 of 63 293 infants had HBV due to MTCT. Without prophylaxis regimens, the pooled HBV MTCT incidence was 31.3%, ranging from 0.0% (95% confidence interval [CI] 0.0%-6.0%; European Region) to 46.1% (95% CI 29.7%-63.0%; Western Pacific Region). Following the introduction of the hepatitis B vaccine, the HBV MTCT incidence decreased from 82.9% to 15.9% in HBeAg-positive women and from 10.3% to 2.3% in HBeAg-negative women. Maternal peripartum antiviral treatment alongside infant immunoprophylaxis further decreased MTCT incidence to 0.3% (95% CI 0.1%-0.5%). Despite infant immunoprophylaxis, the incidences of MTCT at maternal HBV DNA levels of <2.30, 2.00-3.29, 3.00-4.29, 4.00-5.29, 5.00-6.29, 6.00-7.29 and ≥7.00 log10  IU/ml were 0.0% (95% CI 0.0%-0.0%), 0.0% (95% CI 0.0%-0.0%), 0.0% (95% CI 0.0%-0.5%), 0.6% (95% CI 0.0%-2.6%), 1.0% (95% CI 0.0%-3.1%), 4.3% (95% CI 1.8%-7.5%), and 9.6% (95% CI 7.0%-12.5%), respectively. CONCLUSIONS: HBV MTCT incidence varies across regions. The Western Pacific Region bears the heaviest burden. Peripartum antiviral prophylaxis plus infant immunoprophylaxis is promising for interrupting HBV MTCT. Regarding the HBV DNA threshold for peripartum antiviral prophylaxis, maternal HBV DNA of 4.00 log10  IU/ml or greater seems justified.


Asunto(s)
Hepatitis B , Complicaciones Infecciosas del Embarazo , Lactante , Femenino , Embarazo , Humanos , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Antígenos de Superficie de la Hepatitis B/uso terapéutico , Antígenos e de la Hepatitis B/uso terapéutico , Incidencia , Antivirales/uso terapéutico , Vacunas contra Hepatitis B , ADN Viral , Periodo Periparto , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/prevención & control , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Hepatitis B/epidemiología , Hepatitis B/prevención & control , Hepatitis B/tratamiento farmacológico , Virus de la Hepatitis B/genética
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