272 results on '"Zifeng Yang"'
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2. Infection rates of 70% of the population observed within 3 weeks after release of COVID-19 restrictions in Macao, China
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Jingyi Liang, Ruibin Liu, Wei He, Zhiqi Zeng, Yangqianxi Wang, Boyuan Wang, Lixi Liang, Tong Zhang, C.L. Philip Chen, ChiWai Chang, Chitin Hon, Eric H.Y. Lau, Zifeng Yang, and KaLok Tong
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Microbiology (medical) ,Infectious Diseases - Published
- 2023
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3. COVID-19 focused series: diagnosis and forecast of COVID-19
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Tao Xu, Jing Cheng, Zifeng Yang, Wenda Guan, and Zhiqi Zeng
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Pulmonary and Respiratory Medicine - Published
- 2023
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4. Simultaneous profiling and quantification of 25 eicosanoids in human serum by ultrahigh-performance liquid chromatography coupled to tandem mass spectrometry
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Yuanyuan, Lu, Zhitong, Mai, Hongxia, Zhou, Wenda, Guan, Shiguan, Wu, Heyan, Zou, Maoting, Shen, Yangqing, Zhan, Feng, Ye, Minshan, Qiu, Lihan, Shen, Beibei, Zhao, and Zifeng, Yang
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Tandem Mass Spectrometry ,Influenza, Human ,Solid Phase Extraction ,Humans ,Eicosanoids ,Biochemistry ,Chromatography, High Pressure Liquid ,Chromatography, Liquid ,Analytical Chemistry - Abstract
The eicosanoid metabolic pathway is responsible for mediating the production of various inflammatory factors that are closely related to the development and resolution of inflammation. In biological matrices, the major quantifying obstacles were shown to be the oxidation and low quantities of eicosanoids and their metabolites. This study aimed to develop a reliable, sensitive ultrahigh-performance liquid chromatography coupled to a tandem mass spectrometry (UPLC–MS/MS) method to quantify eicosanoids in human serum. Solid-phase extraction (SPE) was used for sample preparation. The approach employed continuous ionization polarity switching. The target eicosanoids showed good linearity over the investigated concentration range (r2 > 0.99). The recovery rates were over 64.5%, and the matrix effects ranged from 73.0 to 128.0%. The limits of quantification were 0.048 ~ 0.44 ng/mL. For the broad concentration range, the CV % for accuracy and precision were less than ± 20%. We successfully applied this method to rapidly analyse 74 serum samples from severe influenza pneumonia, severe bacterial pneumonia and healthy individuals. Eicosanoid-related metabolite concentrations were quantified within a range similar to those of previously published articles. Compared to healthy individuals, our application found that 20-HETE, 14,15-EET and 11,12-EET were upregulated in severe influenza pneumonia patients, while LTB4 was downregulated. 8-HETE and 5-HETE were upregulated in severe bacterial pneumonia patients, while LTE4 was downregulated. This approach provides a means for monitoring the low quantities of eicosanoids in biological matrices, and our finding that different characteristic metabolite profiles may help discriminate the induction of severe pneumonia patients.
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- 2022
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5. Morphology and Hemodynamics of Cerebral Arteries and Aneurysms in a Rare Pair of Monozygotic Twins
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Ludwig, Hang Yi, Zifeng Yang, Luke C. Bramlage, and Bryan R.
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identical twins ,configuration ,blood flow characteristics ,environmental and genetic factors ,neurovascular diseases - Abstract
In this preliminary study, the underlying pathophysiology mechanisms of cerebral aneurysms (CAs) in monozygotic twins (MTs) were investigated via a rare pair of MTs (twin A and twin B) involving four reconstructed arterial models using preclinical information. First, dimensions and configurated outlines of three-perspective geometries were compared. Adopting an in-vitro validated numerical CA model, hemodynamic characteristics were investigated in the MTs, respectively. Despite expected genetic similarities, morphological comparisons show that configurations of cerebral arteries exhibit significant differences between the twins. The ICA size of twin A is larger than that in twin B (2.23~25.86%), varying with specific locations, attributing to variations during embryological developments and environmental influences. Numerical modeling indicates the MTs have some hemodynamic similarities such as pressure distributions (~13,400 Pa) and their oscillatory shear index (OSI) (0~0.49), but present significant differences in local regions. Specifically, the difference in blood flow rate in the MTs is from 16% to 221%, varying with specifically compared arteries. The maximum time-averaged wall shear stress (53.6 Pa vs. 37.8 Pa) and different local OSI distributions were also observed between the MTs. The findings revealed that morphological variations in MTs could be generated by embryological and environmental factors, further influencing hemodynamic characteristics on CA pathophysiology.
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- 2023
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6. De novo purine nucleotide biosynthesis mediated by MoAde4 is required for conidiation, host colonization and pathogenicity in Magnaporthe oryzae
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Osakina Aron, Frankine Jagero Otieno, Ibrahim Tijjani, Zifeng Yang, Huxiao Xu, Shuning Weng, Jiayuan Guo, Songmao Lu, Zonghua Wang, and Wei Tang
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Virulence ,Nucleotides ,Adenine ,Hordeum ,Oryza ,General Medicine ,Spores, Fungal ,Applied Microbiology and Biotechnology ,Fungal Proteins ,Magnaporthe ,Ascomycota ,Gene Expression Regulation, Fungal ,Purine Nucleotides ,Plant Diseases ,Biotechnology - Abstract
Amidophosphoribosyltransferase catalyzes the conversion of 5-phosphoribosyl-1-pyrophosphate into 5-phosphoribosyl-1-amine in the de novo purine biosynthetic pathway. Herein, we identified and characterized the functions of MoAde4, an orthologue of yeast Ade4 in Magnaporthe oryzae. MoAde4 is a 537-amino acid protein containing GATase_6 and pribosyltran domains. MoADE4 transcripts were highly expressed during the conidiation, early-infection, and late-infection stages of the fungus. Disruption of the MoADE4 gene resulted in ΔMoade4 exhibiting adenine, adenosine, and hypoxanthine auxotrophy on minimal medium. Conidia quantification assays showed that sporulation was significantly reduced in the ΔMoade4 mutant. The conidia of ΔMoade4 could still form appressoria but mostly failed to penetrate the rice cuticle. Pathogenicity tests showed that ΔMoade4 was completely nonpathogenic on rice and barley leaves, which was attributed to restricted infectious hyphal growth within the primary cells. The ΔMoade4 mutant was defective in the induction of strong host immunity. Exogenous adenine partially rescued conidiation, infectious hyphal growth, and the pathogenicity defects of the ΔMoade4 mutant on barley and rice leaves. Taken together, our results demonstrated that purine nucleotide biosynthesis orchestrated by MoAde4 is required for fungal development and pathogenicity in M. oryzae. These findings therefore act as a suitable target for antifungal development against recalcitrant plant fungal pathogens. KEY POINTS: • MoAde4 is crucial for de novo purine nucleotide biosynthesis. • MoAde4 is pivotal for conidiogenesis and appressorium development of M. oryzae. • MoAde4 is involoved in the pathogenicity of M. oryzae.
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- 2022
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7. The genetic characterization of hemagglutinin (HA), neuraminidase (NA) and polymerase acidic (PA) genes of H3N2 influenza viruses circulated in Guangdong Province of China during 2019–2020
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Yong Liu, Wenxiang Jin, Wenda Guan, Zhiqi Zeng, and Zifeng Yang
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China ,Influenza A Virus, H3N2 Subtype ,Neuraminidase ,Hemagglutinin Glycoproteins, Influenza Virus ,General Medicine ,Evolution, Molecular ,Epitopes ,Virology ,Influenza, Human ,Genetics ,Humans ,RNA, Viral ,Molecular Biology ,Phylogeny - Abstract
The evolution of seasonal influenza viruses, which can cause virus antigenic drift to escape human herd immunity, is a significant public health problem. Here, we obtained hemagglutinin (HA), neuraminidase (NA), and polymerase acidic protein (PA) the gene sequences of 84 influenza virus isolates collected in Guangdong Province during the 2019-2020 influenza season. Phylogenetic analyses revealed all these isolates were genetically similar to the viruses of clade 3C2a A1b, specifically those within subclades of A1b 137F (59 cases), A1b 186D (19 cases), and A1b 94 N (6 cases). The influenza virus isolates were distinct from the World Health Organization recommended influenza A vaccine virus for the 2019-2020 Northern Hemisphere season (A/Kansas/14/2017; H3N2). Phylogenies inferred from the individual gene segment sequences revealed that one reassortment event occurred among these clades. The genetic variation involved mutations within viral antigenic epitopes and two N-glycosylation site alterations. The novel mutation sites of G202D and D206N in the HA gene, E344K in the NA gene, and K626R in the PA gene which may affect the spread of the virus were observed. We investigated the evolution of these genes and found that the HA and NA genes were under greater pressure than PA gene. Mutations associated with conferring resistance to NA inhibitors or baloxavir acid were not found. Our results suggest that a rapid evolution of the H3N2 influenza virus occurred, thus continuous monitoring is critical for establishing appropriate vaccine formulations or drug delivery for targeting influenza.
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- 2022
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8. Human airway and nasal organoids reveal escalating replicative fitness of SARS-CoV-2 emerging variants
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Cun Li, Jingjing Huang, Yifei Yu, Zhixin Wan, Man Chun Chiu, Xiaojuan Liu, Shuxin Zhang, Jian-Piao Cai, Hin Chu, Gang Li, Jasper Fuk-Woo Chan, Kelvin Kai-Wang To, Zifeng Yang, Shibo Jiang, Kwok-yung Yuen, Hans Clevers, and Jie Zhou
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Multidisciplinary - Abstract
The high transmissibility of SARS-CoV-2 Omicron subvariants was generally ascribed to immune escape. It remained unclear whether the emerging variants have gradually acquired replicative fitness in human respiratory epithelial cells. We sought to evaluate the replicative fitness of BA.5 and earlier variants in physiologically active respiratory organoids. BA.5 exhibited a dramatically increased replicative capacity and infectivity than B.1.1.529 and an ancestral strain wildtype (WT) in human nasal and airway organoids. BA.5 spike pseudovirus showed a significantly higher entry efficiency than that carrying WT or B.1.1.529 spike. Notably, we observed prominent syncytium formation in BA.5-infected nasal and airway organoids, albeit elusive in WT- and B.1.1.529-infected organoids. BA.5 spike-triggered syncytium formation was verified by lentiviral overexpression of spike in nasal organoids. Moreover, BA.5 replicated modestly in alveolar organoids, with a significantly lower titer than B.1.1.529 and WT. Collectively, the higher entry efficiency and fusogenic activity of BA.5 spike potentiated viral spread through syncytium formation in the human airway epithelium, leading to enhanced replicative fitness and immune evasion, whereas the attenuated replicative capacity of BA.5 in the alveolar organoids may account for its benign clinical manifestation.
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- 2023
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9. Honokiol acts as an AMPK complex agonist therapeutic in non-alcoholic fatty liver disease and metabolic syndrome
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Ruifeng Tian, Jinjie Yang, Xiaoming Wang, Shuaiyang Liu, Ruixiang Dong, Zhenya Wang, Zifeng Yang, Yingping Zhang, Zhiwei Cai, Hailong Yang, Yufeng Hu, Zhi-Gang She, Hongliang Li, Junjie Zhou, and Xiao-Jing Zhang
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Pharmacology ,Complementary and alternative medicine - Abstract
Background Non-alcoholic fatty liver (NAFLD) and its related metabolic syndrome have become major threats to human health, but there is still a need for effective and safe drugs to treat these conditions. Here we aimed to identify potential drug candidates for NAFLD and the underlying molecular mechanisms. Methods A drug repositioning strategy was used to screen an FDA-approved drug library with approximately 3000 compounds in an in vitro hepatocyte model of lipid accumulation, with honokiol identified as an effective anti-NAFLD candidate. We systematically examined the therapeutic effect of honokiol in NAFLD and metabolic syndrome in multiple in vitro and in vivo models. Transcriptomic examination and biotin-streptavidin binding assays were used to explore the underlying molecular mechanisms, confirmed by rescue experiments. Results Honokiol significantly inhibited metabolic syndrome and NAFLD progression as evidenced by improved hepatic steatosis, liver fibrosis, adipose inflammation, and insulin resistance. Mechanistically, the beneficial effects of honokiol were largely through AMPK activation. Rather than acting on the classical upstream regulators of AMPK, honokiol directly bound to the AMPKγ1 subunit to robustly activate AMPK signaling. Mutation of honokiol-binding sites of AMPKγ1 largely abolished the protective capacity of honokiol against NAFLD. Conclusion These findings clearly demonstrate the beneficial effects of honokiol in multiple models and reveal a previously unappreciated signaling mechanism of honokiol in NAFLD and metabolic syndrome. This study also provides new insights into metabolic disease treatment by targeting AMPKγ1 subunit-mediated signaling activation.
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- 2023
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10. A high-throughput drug screening identifies luteolin as a therapeutic candidate for pathological cardiac hypertrophy and heart failure
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Zhenya Wang, Wei Shi, Taibo Wu, Tian Peng, Xiaoming Wang, Shuaiyang Liu, Zifeng Yang, Jia Wang, Peng-Long Li, Ruifeng Tian, Ying Hong, Hailong Yang, Lan Bai, Yufeng Hu, Xu Cheng, Hongliang Li, Xiao-Jing Zhang, and Zhi-Gang She
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Cardiology and Cardiovascular Medicine - Abstract
BackgroundPathological cardiac hypertrophy is commonly resulted from sustained pressure overload and/or metabolic disorder and eventually leads to heart failure, lacking specific drugs in clinic. Here, we aimed to identify promising anti-hypertrophic drug(s) for heart failure and related metabolic disorders by using a luciferase reporter-based high-throughput screening.MethodsA screen of the FDA-approved compounds based on luciferase reporter was performed, with identified luteolin as a promising anti-hypertrophic drug. We systematically examined the therapeutic efficacy of luteolin on cardiac hypertrophy and heart failure in vitro and in vivo models. Transcriptome examination was performed to probe the molecular mechanisms of luteolin.ResultsAmong 2,570 compounds in the library, luteolin emerged as the most robust candidate against cardiomyocyte hypertrophy. Luteolin dose-dependently blocked phenylephrine-induced cardiomyocyte hypertrophy and showed extensive cardioprotective roles in cardiomyocytes as evidenced by transcriptomics. More importantly, gastric administration of luteolin effectively ameliorated pathological cardiac hypertrophy, fibrosis, metabolic disorder, and heart failure in mice. Cross analysis of large-scale transcriptomics and drug-target interacting investigations indicated that peroxisome proliferator activated receptor γ (PPARγ) was the direct target of luteolin in the setting of pathological cardiac hypertrophy and metabolic disorders. Luteolin can directly interact with PPARγ to inhibit its ubiquitination and subsequent proteasomal degradation. Furthermore, PPARγ inhibitor and PPARγ knockdown both prevented the protective effect of luteolin against phenylephrine-induced cardiomyocyte hypertrophy in vitro.ConclusionOur data clearly supported that luteolin is a promising therapeutic compound for pathological cardiac hypertrophy and heart failure by directly targeting ubiquitin-proteasomal degradation of PPARγ and the related metabolic homeostasis.
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- 2023
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11. Inhibition mechanism and antiviral activity of an α-ketoamide based SARS-CoV-2 main protease inhibitor
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Xiaoxin Chen, Xiaodong Huang, Qinhai Ma, Petr Kuzmič, Biao Zhou, Jinxin Xu, Bin Liu, Haiming Jiang, Wenjie Zhang, Chunguang Yang, Shiguan Wu, Jianzhou Huang, Haijun Li, Chaofeng Long, Xin Zhao, Hongrui Xu, Yanan Sheng, Yaoting Guo, Chuanying Niu, Lu Xue, Yong Xu, Jinsong Liu, Tianyu Zhang, James Spencer, Wenbin Deng, Shu-Hui Chen, Xiaoli Xiong, Zifeng Yang, and Nanshan Zhong
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SARS-CoV-2 has demonstrated extraordinary ability to evade antibody immunity by antigenic drift. Small molecule drugs may provide effective therapy while being part of a solution to circumvent SARS-CoV-2 immune escape. In this study we report an α-ketoamide based peptidomimetic inhibitor of SARS-CoV-2 main protease (Mpro), RAY1216. Enzyme inhibition kinetic analysis established that RAY1216 is a slow-tight inhibitor with aKi of 8.6 nM; RAY1216 has a drug-target residence time of 104 min compared to 9 min of PF-07321332 (nirmatrelvir), the antiviral component in Paxlovid, suggesting that RAY1216 is approximately 12 times slower to dissociate from the protease-inhibitor complex compared to PF-07321332. Crystal structure of SARS-CoV-2 Mpro:RAY1216 complex demonstrates that RAY1216 is covalently attached to the catalytic Cys145 through the α-ketoamide warhead; more extensive interactions are identified between bound RAY1216 and Mproactive site compared to PF-07321332, consistent with a more stable acyl-enzyme inhibition complex for RAY1216. In cell culture and human ACE2 transgenic mouse models, RAY1216 demonstrates comparable antiviral activities towards different SARS-CoV-2 virus variants compared to PF-07321332. Improvement in pharmacokinetics has been observed for RAY1216 over PF-07321332 in various animal models, which may allow RAY1216 to be used without ritonavir. RAY1216 is currently undergoing phase III clinical trials (https://clinicaltrials.gov/ct2/show/NCT05620160) to test real-world therapeutic efficacy against COVID-19.
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- 2023
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12. Chinese expert consensus on immunoprophylaxis of common respiratory pathogens in children (2021 edition)
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Zifeng, Yang, Tiejian, Feng, Wenda, Guan, Jianfeng, He, Rongmeng, Jiang, Gang, Liu, Gen, Lu, Quan, Lu, Adong, Shen, Lihong, Sun, Xiaodong, Sun, Yonghong, Yang, Mei, Zeng, Jiushun, Zhou, Kunling, Shen, and Nanshan, Zhong
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Pulmonary and Respiratory Medicine ,Consensus - Abstract
Respiratory tract infections are infectious diseases involving the respiratory tract (such as the sinuses, throat, airways or lungs), which are the common respiratory disorders in children. With the development of society and the improvement of economic conditions, great progress has been made in China in the prevention of common respiratory pathogens in children. As a result, the incidence and mortality of respiratory tract infections in children have dropped sharply in the past decades. However, there is still a certain gap compared with the international leading levels, which can be partly attribute to insufficient public awareness of vaccination, uneven vaccination services of vaccinators, and so on. On the basis of comprehensive analysis of the clinical evidence of immunoprophylaxis of common respiratory pathogens among children in China and abroad, combined with the clinical situation and the experience of experts, the consensus focuses on the characteristics of transmission, clinical manifestations and immunoprophylaxis of common respiratory pathogens in children, so as to provide reference for clinical practice. This consensus document applies to all Centers for Disease Control and Prevention (CDC) staff levels engaged in the prevention and control of related pathogens, vaccinators at vaccination sites, and medical staff in pediatric, respiratory, and infectious diseases departments at all levels in medical institutions.
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- 2022
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13. Co-infecting pathogens can contribute to inflammatory responses and severe symptoms in COVID-19
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Liping Chen, Lihan Shen, Weichen Wu, Wenda Guan, Jinchao Zhou, Gengyan Luo, Qimin Chen, Hongxia Zhou, Zhenxuan Deng, Yaoqing Chen, Wenjing Zhao, Wenxiang Jin, Minshan Qiu, Qianwei Zheng, Yutao Wang, Chen Liu, Xiangxiang Bai, Deyin Guo, Edward C. Holmes, Nanshan Zhong, Mang Shi, and Zifeng Yang
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Coronavirus ,Pulmonary and Respiratory Medicine ,COVID-19 ,Original Article - Abstract
BACKGROUND: The current COVID-19 pandemic is posing a major challenge to public health on a global scale. While it is generally believed that severe COVID-19 results from over-expression of inflammatory mediators (i.e., a “cytokine storm”), it is still unclear whether and how co-infecting pathogens contribute to disease pathogenesis. To address this, we followed the entire course of the disease in cases with severe or critical COVID-19 to determine the presence and abundance of all potential pathogens present—the total “infectome”—and how they interact with the host immune system in the context of severe COVID-19. METHODS: We examined one severe and three critical cases of COVID-19, as well as a set of healthy controls, with longitudinal samples (throat swab, whole blood, and serum) collected from each case. Total RNA sequencing (meta-transcriptomics) was performed to simultaneously investigate pathogen diversity and abundance, as well as host immune responses, in each sample. A Bio-Plex method was used to measure serum cytokine and chemokine levels. RESULTS: Eight pathogens, SARS-CoV-2, Aspergillus fumigatus (A. fumigatus), Mycoplasma orale (M. orale), Myroides odoratus (M. odoratus), Acinetobacter baumannii (A. baumannii), Candida tropicalis, herpes simplex virus (HSV) and human cytomegalovirus (CMV), identified in patients with COVID-19 appeared at different stages of the disease. The dynamics of inflammatory mediators in serum and the respiratory tract were more strongly associated with the dynamics of the infectome compared with SARS-CoV-2 alone. Correlation analysis revealed that pulmonary injury was directly associated with cytokine levels, which in turn were associated with the proliferation of SARS-CoV-2 and co-infecting pathogens. CONCLUSIONS: For each patient, the cytokine storm that resulted in acute lung injury and death involved a dynamic and highly complex infectome, of which SARS-CoV-2 was a component. These results indicate the need for a precision medicine approach to investigate both the infection and host response as a standard means of infectious disease characterization.
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- 2022
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14. Detection of airborne respiratory viruses in pediatric patient rooms in Guangzhou, China
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Yanmin Xie, Eunice Yuen Chi Shiu, Dan Ye, Wenjie Zhang, Wenbo Huang, Zifeng Yang, Benjamin John Cowling, and Nancy Hiu Lan Leung
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BackgroundDespite the controversy of aerosol transmission for different respiratory viruses, there are few direct comparisons. Respiratory virus detection in the air can inform transmission risk assessment in healthcare settings. We aimed to identify five common respiratory viruses in the air in pediatric patient rooms.MethodsWe sampled air with two-stage cyclone samplers continuously for 4 hours in 5-bed pediatric patient rooms in a tertiary hospital in China. Respiratory virus RNA/DNA recovered in the air were quantified by PCR.ResultsWe conducted air sampling on 44 occasions from December 2017 through January 2020, and identified 24, 18, 16, 4 and 8 occasions which had ≥1 patient in the room tested positive for respiratory syncytial virus (RSV), adenovirus (AdV), parainfluenza virus (PIV), influenza B or A virus, respectively. Detection of influenza A viral gene copies was most frequent even when there were no known infected patients in the room (72%). Influenza B, AdV and RSV were detected in low to moderate frequencies, whether there were infected patients in close proximity (13-50%) or not (12-25%). PIV was rarely detected even when air samplers were placed in close proximity to infected patients (8%). About 103–105copies/m3were detected for all detected respiratory viruses.ConclusionsHealthcare workers and visitors likely have substantial exposure to various respiratory viruses including influenza A/B viruses, RSV and AdV in pediatric patient rooms, even in the absence of infected individuals in close proximity, suggesting the potential value of improving indoor ventilation or air disinfection in hospitals.
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- 2023
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15. Challenge on prediction of Influenza virus and SARS‐CoV‐2 virus co‐circulation
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Jingyi Liang, Zhiqi Zeng, Qianying Li, Wenda Guan, Zifeng Yang, and Chitin Hon
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- 2023
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16. Morphology and Hemodynamics of Cerebral Arteries and Aneurysms in a Pair of Monozygotic Twins
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Hang Yi, Zifeng Yang, Luke C Bramlage, and Ludwig R Bryan
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biomedical_chemical_engineering - Abstract
The contribution of genetic and environmental factors to the pathophysiology of cerebral aneurysms in monozygotic twins is under-reported and presents ambiguous arguments. The morphology and hemodynamics of neurovascular arteries in a pair of monozygotic twins (MTs) were investigated to reveal the underlying mechanisms. Four arterial models were reconstructed for the twin A-right brain and left brain, twin B-left brain, and B-left brain without anterior cerebral arteries based on preclinical scanned information. Subsequently, the dimensions, configurations and outlined curves of the three-perspective geometries were compared between the MTs. Adopting an in-vitro validated numerical cerebral aneurysm model, hemodynamic patterns were investigated and compared in the MT models, respectively. Morphological comparisons of the MTs show the size and shape of cerebral arteries exist significant differences, despite of the expected genetic similarities. These differences can be attributed to variations during embryological development and external environmental influences. Qualitatively and generally, numerical results indicate the MTs have some hemodynamic similarities (e.g., time-averaged pressure (TAP) distributions (~13400 Pa), and oscillatory shear index (0~0.49), but present significant differences in specific local arteries due to morphological variances. Specifically, the difference in the volumetric blood flow rate in corresponding arteries between the MTs is from 16% (smallest) in anterior choroidal artery (AChA) to 221% (largest) in the ophthalmic artery (OphA), varying with specific compared arteries. Also, the registered hemodynamic indicators, such as the maximum time-averaged wall shear stress (TWSS) (53.6 Pa vs. 37.8 Pa), and different local OSI distributions were observed between the MTs. The findings revealed that morphological variations in MTs could be generated by embryological and environmental factors, thus assuming they share the identical morphology in cardiovascular and neurovascular systems may lead to significant misevaluations in hemodynamics quantifications and further lesions.
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- 2023
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17. Effects of treatment of non-alcoholic fatty liver disease on heart failure with preserved ejection fraction
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Zifeng Yang, Ruifeng Tian, Xiao-Jing Zhang, Jingjing Cai, Zhi-Gang She, and Hongliang Li
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Cardiology and Cardiovascular Medicine - Abstract
In the past few decades, non-alcoholic fatty liver disease (NAFLD) and heart failure with preserved ejection fraction (HFpEF) have become the most common chronic liver disease and the main form of heart failure (HF), respectively. NAFLD is closely associated with HFpEF by sharing common risk factors and/or by boosting systemic inflammation, releasing other secretory factors, and having an expansion of epicardial adipose tissue (EAT). Therefore, the treatments of NAFLD may also affect the development and prognosis of HFpEF. However, no specific drugs for NAFLD have been approved by the Food and Drug Administration (FDA) and some non-specific treatments for NAFLD are applied in the clinic. Currently, the treatments of NAFLD can be divided into non-pharmacological and pharmacological treatments. Non-pharmacological treatments mainly include dietary intervention, weight loss by exercise, caloric restriction, and bariatric surgery. Pharmacological treatments mainly include administering statins, thiazolidinediones, glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter 2 inhibitors, and metformin. This review will mainly focus on analyzing how these treatments may affect the development and prognosis of HFpEF.
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- 2023
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18. Corrigendum: Investigating the effects of Liushen Capsules (LS) on the metabolome of seasonal influenza: A randomized clinical trial
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Qinhai Ma, Ruihan Chen, Jing Zeng, Biao Lei, Feng Ye, Qihua Wu, Zhengtu Li, Yangqing Zhan, Bin Liu, Bojun Chen, and Zifeng Yang
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Pharmacology ,Pharmacology (medical) - Published
- 2023
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19. Yu Ping Feng San Protects Mice Against Porcine Pancreatic Elastase-Induced Emphysema by Blunting Innate Immune Response
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Zifeng Yang, Lingzhu Deng, Yaorong Chen, Ruifeng Chen, Shengle Qin, Tao Huang, Xiao Wu, Shiyun Liang, Tongmei Shi, Xin Zhao, and Runfeng Li
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- 2023
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20. Combining Network Pharmacology and Metabolomics to Reveal the Mechanism of Liu Shen Capsules Against Inflammatory and Influenza H3N2 Virus
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Ruihan Chen, Bin Liu, Xuejun Cai, Peifang Xie, Zexin Chen, Wanli Qiu, Ting Wang, Yongjie Su, Wanyi Huang, Qinhai Ma, and Zifeng Yang
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- 2023
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21. 3-Does Inactivated Vaccine with 1-Does Mrna Providing Strong Protection Against COVID-19 Infection Among Young and Middle-Age Groups during 2022 Omicron Wave in Macao (China): An Observatory Study
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JH Zhang, Boyuan Wang, Eric H.Y. Lau, Zhiqi Zeng, Wei He, C. L. Philip Chen, Chiwai Chang, Zifeng Yang, KaLok Tong, Nan-Shan Zhong, and Chitin Hon
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- 2023
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22. How fast and how well the Omicron epidemic was curtailed. A Guangzhou experience to share
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Wenfeng, Cai, Zifeng, Yang, Jingyi, Liang, Zhengshi, Lin, Yu, Ma, Chun, Chen, Yan, Li, Yongming, Li, Zhitong, Mai, Kailin, Mai, Xuetao, Kong, Xingyi, Liang, Qianying, Li, Chuanmeizi, Tu, Canxiong, Chen, Chitin, Hon, Pengzhe, Qin, Ke, Li, Xiaoning, Li, Yutian, Miao, Xuexing, Liu, Wenda, Guan, Zhiqi, Zeng, Wanli, Qiu, Wei, He, Lin, Zhang, Zhicong, Yang, and Nanshan, Zhong
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Public Health, Environmental and Occupational Health - Abstract
IntroductionSARS-CoV-2 has ravaged the world and undergone multiple mutations during the course of the COVID-19 pandemic. On 7 April 2022, an epidemic caused by SARS-CoV-2 Omicron (BA.2) variant broke out in Guangzhou, China, one of the largest transportation and logistical hubs of the country.MethodsTo fast curtained the Omicron epidemic, based on the routine surveillance on the risk population of SARS-CoV-2 infection, we identify key places of the epidemic and implement enhanced control measures against Omicron.ResultsTransmission characteristics of the Omicron variant were analyzed for 273 confirmed cases, and key places involved in this epidemic were fully presented. The median incubation time and the generation time were 3 days, and the reproduction number Rt was sharply increased with a peak of 4.20 within 2 days. We tried an all-out effort to tackle the epidemic in key places, and the proportion of confirmed cases increased from 61.17% at Stage 2 to 88.89% at Stage 4. Through delimited risk area management, 99 cases were found, and the cases were isolated in advance for 2.61 ± 2.76 days in a lockdown zone, 0.44 ± 1.08 days in a controlled zone, and 0.27 ± 0.62 days in a precautionary zone. People assigned with yellow code accounted for 30.32% (84/277) of confirmed COVID-19 cases, and 83.33% of them were detected positive over 3 days since code assignment. For the districts outside the epicenter, the implementation duration of NPIs was much shorter compared with the Delta epidemic last year.ConclusionBy blocking out transmission risks and adjusting measures to local epidemic conditions through the all-out effort to tackle the epidemic in key places, by delimiting risk area management, and by conducting health code management of the at-risk population, the Omicron epidemic could be contained quickly.
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- 2022
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23. Type 2C Protein Phosphatases MoPtc5 and MoPtc7 Are Crucial for Multiple Stress Tolerance, Conidiogenesis and Pathogenesis of Magnaporthe oryzae
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Jules Biregeya, Wilfred M. Anjago, Shu Pan, Ruina Zhang, Zifeng Yang, Meilian Chen, Abah Felix, Huxiao Xu, Yaqi Lin, Oswald Nkurikiyimfura, Yakubu Saddeeq Abubakar, Zonghua Wang, and Wei Tang
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Microbiology (medical) ,blast fungus ,protein phosphatases ,phosphorylation ,pathogenicity ,Plant Science ,Ecology, Evolution, Behavior and Systematics - Abstract
Protein kinases and phosphatases catalyze the phosphorylation and dephosphorylation of their protein substrates, respectively, and these are important mechanisms in cellular signal transduction. The rice blast fungus Magnaporthe oryzae possesses 6 protein phosphatases of type 2C class, including MoPtc1, 2, 5, 6, 7 and 8. However, only very little is known about the roles of these phosphatases in filamentous fungi. Here in, we deployed genetics and molecular biology techniques to identify, characterize and establish the roles of MoPtc5 and MoPtc7 in M. oryzae development and pathogenicity. We found that during pathogen-host interaction, MoPTC7 is differentially expressed. Double deletion of MoPTC7 and MoPTC5 suppressed the fungal vegetative growth, altered its cell wall integrity and reduced its virulence. The two genes were found indispensable for stress tolerance in the phytopathogen. We also demonstrated that disruption of any of the two genes highly affected appressorium turgor generation and Mps1 and Osm1 phosphorylation levels. Lastly, we demonstrated that both MoPtc5 and MoPtc7 are localized to mitochondria of different cellular compartments in the blast fungus. Taken together, our study revealed synergistic coordination of M. oryzae development and pathogenesis by the type 2C protein phosphatases.
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- 2022
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24. Review for 'Antiviral effect and mechanism of Phillyrin and its reformulated FS21 against influenza'
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Zifeng Yang
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- 2022
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25. Containment of SARS-CoV-2 Delta strain in Guangzhou, China by quarantine and social distancing: a modelling study
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Zhiqi, Zeng, Tong, Wu, Zhijie, Lin, Lei, Luo, Zhengshi, Lin, Wenda, Guan, Jingyi, Liang, Minfei, Yu, Peikun, Guan, Wei, He, Zige, Liu, Guibin, Lu, Peifang, Xie, Canxiong, Chen, Eric H Y, Lau, Zifeng, Yang, Chitin, Hon, and Jianxing, He
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China ,Multidisciplinary ,SARS-CoV-2 ,Physical Distancing ,Humans ,COVID-19 - Abstract
China detected the first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with Delta variant in May 2021. We assessed control strategies against this variant of concern. We constructed a robust transmission model to assess the effectiveness of interventions against the Delta variant in Guangzhou with initial quarantine/isolation, followed by social distancing. We also assessed the effectiveness of alternative strategies and that against potentially more infectious variants. The effective reproduction number (Rt) fell below 1 when the average daily number of close contacts was reduced to ≤ 7 and quarantine/isolation was implemented on average at the same day of symptom onset in Guangzhou. Simulations showed that the outbreak could still be contained when quarantine is implemented on average 1 day after symptom onset while the average daily number of close contacts was reduced to ≤ 9 per person one week after the outbreak's beginning. Early quarantine and reduction of close contacts were found to be important for containment of the outbreaks. Early implementation of quarantine/isolation along with social distancing measures could effectively suppress spread of the Delta and more infectious variants.
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- 2022
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26. Exploration of SARS-CoV-2 3CLpro Inhibitors by Virtual Screening Methods, FRET Detection, and CPE Assay
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Guanhua Du, Ai-Lin Liu, Qinhai Ma, Jun Zhao, Yi Liu, Baoyue Zhang, Zhe Wang, Pengfei Guo, Minsi Meng, and Zifeng Yang
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General Chemical Engineering ,medicine.medical_treatment ,Computational biology ,Library and Information Sciences ,medicine.disease_cause ,Antiviral Agents ,Article ,chemistry.chemical_compound ,Molecular descriptor ,Fluorescence Resonance Energy Transfer ,medicine ,Humans ,Protease Inhibitors ,IC50 ,Coronavirus ,Virtual screening ,Protease ,SARS-CoV-2 ,Chemistry ,Scutellarein ,COVID-19 ,Bayes Theorem ,Biological activity ,General Chemistry ,Computer Science Applications ,Förster resonance energy transfer - Abstract
COVID-19 caused by a novel coronavirus (SARS-CoV-2) has been spreading all over the world since the end of 2019, and no specific drug has been developed yet. 3C-like protease (3CLpro) acts as an important part of the replication of novel coronavirus and is a promising target for the development of anticoronavirus drugs. In this paper, eight machine learning models were constructed using naïve Bayesian (NB) and recursive partitioning (RP) algorithms for 3CLpro on the basis of optimized two-dimensional (2D) molecular descriptors (MDs) combined with ECFP_4, ECFP_6, and MACCS molecular fingerprints. The optimal models were selected according to the results of 5-fold cross verification, test set verification, and external test set verification. A total of 5766 natural compounds from the internal natural product database were predicted, among which 369 chemical components were predicted to be active compounds by the optimal models and the EstPGood values were more than 0.6, as predicted by the NB (MD + ECFP_6) model. Through ADMET analysis, 31 compounds were selected for further biological activity determination by the fluorescence resonance energy transfer (FRET) method and cytopathic effect (CPE) detection. The results indicated that (+)-shikonin, shikonin, scutellarein, and 5,3′,4′-trihydroxyflavone showed certain activity in inhibiting SARS-CoV-2 3CLpro with the half-maximal inhibitory concentration (IC50) values ranging from 4.38 to 87.76 μM. In the CPE assay, 5,3′,4′-trihydroxyflavone showed a certain antiviral effect with an IC50 value of 8.22 μM. The binding mechanism of 5,3′,4′-trihydroxyflavone with SARS-CoV-2 3CLpro was further revealed through CDOCKER analysis. In this study, 3CLpro prediction models were constructed based on machine learning algorithms for the prediction of active compounds, and the activity of potential inhibitors was determined by the FRET method and CPE assay, which provide important information for further discovery and development of antinovel coronavirus drugs.
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- 2021
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27. AC/DC system construction and analysis of business model under multi-station fusion model
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Tong Feifei, Chuangxin Guo, Chutong Wang, Zifeng Yang, Zhendong Du, Zuxian Wu, and Kang Yin
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Multi-station fusion ,business.product_category ,Computer science ,business.industry ,Reliability (computer networking) ,Photovoltaic system ,Markov process ,TK1-9971 ,Reliability engineering ,Charging station ,symbols.namesake ,Base station ,General Energy ,Spare part ,Electric vehicle ,symbols ,Data center ,Electrical engineering. Electronics. Nuclear engineering ,business ,Business model - Abstract
This paper focuses on a novel model named multi-station fusion (MSF). The proposed model integrates transformer substation, data center, energy storage system (ESS), photovoltaic (PV), electric vehicle charging station (EVCS), connection information base station and other systems. It aims at improving the utilization rate of the spare space in existing substation, reducing operation and maintenance cost, and increasing the revenue of power grid enterprises. This paper designs three types of AC/DC system based on reliability priority, economy priority and retrofit flexibility priority. Markov process Monte Carlo method is introduced to verify data center reliability in MSF. The business model of MSF is analyzed. Finally, the construction scheme of MSF model, the contents of the planning considerations and cost–benefit study demonstrate the economic efficiency of the proposed model.
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- 2021
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28. Machine Learning for Aiding Blood Flow Velocity Estimation Based on Angiography
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Swati Padhee, Mark Johnson, Hang Yi, Zifeng Yang, and Tanvi Banerjee
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biomedical_chemical_engineering ,Bioengineering ,machine learning (ML) ,convolutional neural networks (CNN) ,computational fluid dynamics (CFD) ,optical flow method (OFM) ,dye perfusion ,hemodynamics ,least absolute shrinkage and selection operator (LASSO) ,angiography ,cardiovascular ,particle image velocimetry (PIV) - Abstract
Computational fluid dynamics (CFD) is widely employed to predict hemodynamic characteristics in arterial models, while not friendly to clinical applications due to the complexity of numerical simulations. Alternatively, this work proposed a framework to estimate hemodynamics in vessels based on angiography images using machine learning (ML) algorithms. First, the iodine contrast perfusion in blood was mimicked by a flow of dye diffusing into water in the experimentally validated CFD modeling. The generated projective images from simulations imitated the counterpart of light passing through the flow field as an analogy of X-ray imaging. Thus, the CFD simulation provides both the ground truth velocity field and projective images of dye flow patterns. The rough velocity field was estimated using the optical flow method (OFM) based on 53 projective images. ML training with least absolute shrinkage, selection operator and convolutional neural network was conducted with CFD velocity data as the ground truth and OFM velocity estimation as the input. The performance of each model was evaluated based on mean absolute error and mean squared error, where all models achieved or surpassed the criteria of 3 × 10−3 and 5 × 10−7 m/s, respectively, with a standard deviation less than 1 × 10−6 m/s. Finally, the interpretable regression and ML models were validated with over 613 image sets. The validation results showed that the employed ML model significantly reduced the error rate from 53.5% to 2.5% on average for the v-velocity estimation in comparison with CFD. The ML framework provided an alternative pathway to support clinical diagnosis by predicting hemodynamic information with high efficiency and accuracy.
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- 2022
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29. Immunization with a Prefusion SARS-CoV-2 Spike Protein Vaccine (RBMRNA-176) Protects against Viral Challenge in Mice and Nonhuman Primates
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Qinhai Ma, Runfeng Li, Jianmin Guo, Man Li, Lin Ma, Jun Dai, Yongxia Shi, Jinlong Dai, Yuankeng Huang, Cailing Dai, Weiqi Pan, Huiling Zhong, Hong Zhang, Jian Wen, Haoting Zhao, Linping Wu, Wei Yang, Biliang Zhang, and Zifeng Yang
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Pharmacology ,Infectious Diseases ,Drug Discovery ,Immunology ,SARS-CoV-2 ,vaccine ,spike protein ,mice ,nonhuman primates ,Pharmacology (medical) - Abstract
There is an urgent need for a broad-spectrum and protective vaccine due to the emergence and rapid spreading of more contagious SARS-CoV-2 strains. We report the development of RBMRNA-176, a pseudouridine (Ψ) nucleoside-modified mRNA-LNP vaccine encoding pre-fusion stabilized trimeric SARS-CoV-2 spike protein ectodomain, and evaluate its immunogenicity and protection against virus challenge in mice and nonhuman primates. A prime-boost immunization with RBMRNA-176 at intervals of 21 days resulted in high IgG titers (over 1:819,000 endpoint dilution) and a CD4+ Th1-biased immune response in mice. RBMRNA-176 vaccination induced pseudovirus-neutralizing antibodies with IC50 ranging from 1:1020 to 1:2894 against SARS-CoV-2 spike pseudotyped wild-type and variant viruses, including Alpha, Beta, Gamma, and Kappa. Moreover, significant control of viral replication and histopathology in lungs was observed in vaccinated mice. In nonhuman primates, a boost given by RBMRNA-176 on day 21 after the prime induced a persistent and sustained IgG response. RBMRNA-176 vaccination also protected macaques against upper and lower respiratory tract infection, as well as lung injury. Altogether, these findings support RBMRNA-176 as a vaccine candidate for prevention of COVID-19.
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- 2022
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30. Predicting Surgical Benefit for Primary Tumor Resection in Patients with Stage IV Colorectal Cancer
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Yuesheng Yang, Zifeng Yang, Zejian Lyu, Junjiang Wang, Deqing Wu, and Yong Li
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Purpose There exists continuous controversy regarding the effect of primary tumor resection (PTR) for stage IV colorectal cancer (CRC) patients. Little is known about how to predict the patients’ survival benefit from PTR. This study aimed to develop a tool for surgical benefit prediction. Methods Stage IV CRC patients diagnosed between 2010 and 2015 from the Surveillance, Epidemiology, and End Results database were included. After propensity score matching, patients receiving PTR that survived longer than the median cancer-specific survival (CSS) time of those who did not undergo PTR were considered to benefit from surgery. Logistic regression analysis identified prognostic factors influencing the surgical benefit, based on which a nomogram was constructed. A user-friendly webserver was then built for convenient clinical use. The predictive model was assessed using Harrell’s concordance index, calibration plot, receiver operative curve and decision curve analysis. Results The median CSS of the PTR group was 23 months, which was significantly longer than the non-PTR group (12 months, P
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- 2022
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31. Myricetin possesses the potency against SARS-CoV-2 infection through blocking viral-entry facilitators and suppressing inflammation in rats and mice
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Hudan Pan, Jinlian He, Zifeng Yang, Xiaojun Yao, Han Zhang, Runfeng Li, Yao Xiao, Caiping Zhao, Haiming Jiang, Yuntao Liu, Zhanguo Li, Bin Guo, Chuanhai Zhang, Run-Ze Li, and Liang Liu
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Pharmacology ,Complementary and alternative medicine ,Drug Discovery ,Pharmaceutical Science ,Molecular Medicine - Published
- 2023
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32. The traditional herbal formulation, Jianpiyifei II, reduces pulmonary inflammation induced by influenza A virus and cigarette smoke in mice
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Qi Wang, Lei Wu, Zifeng Yang, Ziyao Liang, Qiuling Du, Long Fan, Tiantian Cai, Lin Lin, Xuhua Yu, and Ross Vlahos
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0301 basic medicine ,Exacerbation ,Herbal Medicine ,Inflammation ,medicine.disease_cause ,Proinflammatory cytokine ,Pulmonary Disease, Chronic Obstructive ,03 medical and health sciences ,0302 clinical medicine ,Smoke ,Influenza, Human ,medicine ,Influenza A virus ,Animals ,Humans ,Lung ,Mice, Inbred BALB C ,COPD ,medicine.diagnostic_test ,business.industry ,Smoking ,Pneumonia ,General Medicine ,medicine.disease ,Disease Models, Animal ,030104 developmental biology ,Bronchoalveolar lavage ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Immunology ,Cytokines ,Female ,medicine.symptom ,business ,Viral load - Abstract
Chronic obstructive pulmonary disease (COPD) is a worldwide chronic inflammatory lung disease, and influenza A virus (IAV) infection is a common cause of acute exacerbations of COPD (AECOPD). Therefore, targeting viral infections represents a promising strategy to prevent the occurrence and development of inflammatory flare ups in AECOPD. Jianpiyifei II (JPYFII) is a traditional herbal medicine used in China to treat patients with COPD, and its clinical indications are not well understood. However, investigation of the anti-inflammatory effects and underlying mechanism using an animal model of smoking have been reported in a previous study by our group. In addition, some included herbs, such as Radix astragali and Radix aupleuri, were reported to exhibit antiviral effects. Therefore, the aim of the present study was to investigate whether JPYFII formulation relieved acute inflammation by clearing the IAV in a mouse model that was exposed to cigarette smoke experimentally. JPYFII formulation treatment during smoke exposure and IAV infection significantly reduced the number of cells observed in bronchoalveolar lavage fluid (BALF), expression of proinflammatory cytokines, chemokines, superoxide production, and viral load in IAV-infected and smoke-exposed mice. However, JPYFII formulation treatment during smoke exposure alone did not reduce the number of cells in BALF or the expression of Il-6, Tnf-a, and Il-1β. The results demonstrated that JPYFII formulation exerted an antiviral effect and reduced the exacerbation of lung inflammation in cigarette smoke (CS)-exposed mice infected with IAV. Our results suggested that JPYFII formulation could potentially be used to treat patients with AECOPD associated with IAV infection.
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- 2021
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33. Developing an
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Hang, Yi, Zifeng, Yang, Mark, Johnson, Luke, Bramlage, and Bryan, Ludwig
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- 2022
34. Endoplasmic reticulum membrane protein MoScs2 is important for asexual development and pathogenesis of Magnaporthe oryzae
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Jun Zhang, Xuehang Chen, Zifeng Yang, Huxiao Xu, Shuning Weng, Zonghua Wang, and Wei Tang
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Microbiology (medical) ,Microbiology - Abstract
Most secretory proteins are folded and modified in the endoplasmic reticulum (ER). In Saccharomyces cerevisiae, the absence of Scs2 protein will lead to the separation of the endoplasmic reticulum and plasma membrane, resulting in endoplasmic reticulum dysfunction, but its function is not clear in rice blast fungus or even filamentous fungus. In this study, we report the identification and characterization of MoSCS2 in the pathogenesis of the rice blast fungus Magnaporthe oryzae. Protein subcellular localization showed that MoSCS2 is mainly localized in the endoplasmic reticulum. Compared to the wild-type strain Guy11, the deletion mutant ΔMoscs2 showed a significant reduction in growth and conidiation. MoSCS2 deficiency also resulted in abnormal conidial morphology and septum formation. The ΔMoscs2 mutant shows delayed appressorium formation, and the appressorium of ΔMoscs2 mutant could not form huge turgor pressure to penetrate the host epidermal cell wall. Pathogenicity and plant leave infection assays showed that knockout of MoSCS2 significantly inhibited the expansion of the invasive hyphae in host cells, ultimately leading to the decline of pathogenicity. Moreover, MoSCS2 gene is also involved in the regulation of cell wall and endoplasmic reticulum stress response. In conclusion, MoSCS2 plays an important role in the growth, asexual production, conidia morphogenesis, infection-related morphogenesis and pathogenicity of M. oryzae.
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- 2022
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35. Hemodynamic characteristics in a cerebral aneurysm model using non-Newtonian blood analogues
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Hang Yi, Zifeng Yang, Mark Johnson, Luke Bramlage, and Bryan Ludwig
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Fluid Flow and Transfer Processes ,Mechanics of Materials ,Mechanical Engineering ,Computational Mechanics ,Condensed Matter Physics - Abstract
This study aims to develop an experimentally validated computational fluid dynamics (CFD) model to estimate hemodynamic characteristics in cerebral aneurysms (CAs) using non-Newtonian blood analogues. Blood viscosities varying with shear rates were measured under four temperatures first, which serves as the reference for the generation of blood analogues. Using the blood analogue, particle image velocimetry (PIV) measurements were conducted to quantify flow characteristics in a CA model. Then, using the identical blood properties in the experiment, CFD simulations were executed to quantify the flow patterns, which were used to compare with the PIV counterpart. Additionally, hemodynamic characteristics in the simplified Newtonian and non-Newtonian models were quantified and compared using the experimentally validated CFD model. Results showed the proposed non-Newtonian viscosity model can predict blood shear-thinning properties accurately under varying temperatures and shear rates. Another developed viscosity model based on the blood analogue can well represent blood rheological properties. The comparisons in flow characteristics show good agreements between PIV and CFD, demonstrating the developed CFD model is qualified to investigate hemodynamic factors within CAs. Furthermore, results show the differences of absolute values were insignificant between Newtonian and non-Newtonian fluids in the distributions of wall shear stress (WSS) and oscillatory shear index (OSI) on arterial walls. However, not only does the simplified Newtonian model underestimate WSS and OSI in most regions of the aneurysmal sac, but it also makes mistakes in identifying the high OSI regions on the sac surface, which may mislead the hemodynamic assessment on the pathophysiology of CAs.
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- 2022
36. Culturing Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for Diagnosis and Genome Sequencing
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Zhiqi Zeng, Hua Guo, Liping Chen, Zhengshi Lin, Wenda Guan, Yutao Wang, Haiming Jiang, Xiao Wu, Yong Yin, Zelong Gao, Canxiong Chen, and Zifeng Yang
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Biochemistry (medical) ,Clinical Biochemistry - Abstract
Objective The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection “re-positive” phenomenon is encountered clinically. The accuracy of a viral nucleic acid test is crucial to prevent reintroduction of the virus into the community. This study evaluated the effect of virus culturing on increasing the sensitivity and specificity of real-time polymerase chain reaction (RT-PCR) detection and viral genomic sequencing. Methods A series of tenfold dilutions of a SARS-CoV-2 viral stock were conducted and cultured for either 24 or 48 hours. The viral load of cultured samples was determined by RT-PCR. The cultured and non-cultured samples of 1x 50% tissue culture infectious dose (TCID50) were sequenced using metagenomic next-generation sequencing. The depth and coverage of SARS-CoV-2 genome were measured. Results The lowest viral load detectable in a sample with RT-PCR was 0.01 TCID50. After a 24-h culture, the viral ORF 1ab and N-gene cycle threshold (CT) values were reduced by 4.4 points and 1 point, respectively. One TCID50 viral load of post 24-h culture revealed the sequence depth reached an average of 752 reads, compared with 0.15 in the nonculture; furthermore, the coverage was 99.99% while 6.42% in the nonculture. Conclusion These results indicate that virus culturing can significantly increase the viral load, which can increase the certainty of true-positive detection of the viral nucleic acids, and improve the quality of virus genomic sequencing.
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- 2022
37. Investigating the effects of Liushen Capsules on the metabolome of seasonal influenza: A randomized clinical trial
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Qinhai Ma, Ruihan Chen, Jing Zeng, Biao Lei, Feng Ye, Qihua Wu, Zhengtu Li, Yangqing Zhan, Bin Liu, Bojun Chen, and Zifeng Yang
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Pharmacology ,Pharmacology (medical) - Abstract
Background: Traditional Chinese Medicines (TCMs) are effective strategies for preventing influenza infection. Liushen Capsules can inhibit influenza virus proliferation, significantly mitigate virus-induced inflammation and improve acute lung injury in vitro or in vivo. However, the efficacy and safety of LS in clinical trials, and the role of LS in regulating metabolites in patients are not well known.Materials and methods: A randomized, double-blind, placebo-controlled clinical trial was designed in this study. All participants were enrolled between December 2019 and November 2020. The efficacy and safety were assessed by primary efficacy endpoint ((area under the curve (AUC) analysis)) and secondary endpoint (individual scores for each symptom, remission of symptoms, and rates of inflammatory factors). The serum samples were collected from patients to detect the levels of inflammatory factors using RT-PCR and to identify metabolites using a non-targeted metabolomics ultra-performance liquid chromatography-tandem mass spectrometry (LC-MS).Results: 81 participants from The Second Affiliated Hospital of Guangzhou University of Chinese Medicine and the First Affiliated Hospital of Guangzhou Medical University were completed the full study. After 14 days of intervention, the area under the curve (AUC) of the total symptom scores in LS group was significantly smaller than that in Placebo group (p < 0.001). Alleviation of sore throat, cough and nasal congestion in the LS group was significantly better than that in the Placebo group. The time and number to alleviation of symptoms or complete alleviation of symptoms in LS group was significantly better than that in Placebo group. The adverse effects of clinical therapy were slightly higher in LS group than in Placebo group, but there was no statistical difference. After 14 days of LS intervention, the levels of IL-1ra, Eotaxin, IFN-γ, IL-6, IL-10, IL-13, SCF and TRAIL in serum of participants with influenza infection were significantly decreased compared with Placebo group. It was observed that there were significant differences in the serum metabolic profiles between start- and end- LS groups. Further correlation analysis showed a potential regulatory crosstalk between glycerophospholipids, sphingolipids fatty acyls and excessive inflammation and clinical symptoms. Importantly, it may be closely related to phospholipid, fatty acid, arachidonic acid and amyl-tRNA synthesis pathway metabolic pathways.Conclusion: The study showed there were no clinically significant adverse effects on LS, and a significant improvement in influenza-like symptomatology and inflammatory response in patients treated with LS. Further analysis showed that LS could significantly correct the metabolic disorders in the serum metabolite profile of the patients. This provided new insights into the potential mechanism of LS for the treatment of influenza.
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- 2022
38. Core–Shell Poly(l-lactic acid)-Hyaluronic Acid Nanofibers for Cell Culture and Pelvic Ligament Tissue Engineering
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null Di Zhang, Xiaobo Huang, Huaiming Wang, Yingqi Wei, Zifeng Yang, Rongkang Huang, Weiwen Liang, Xiusen Qin, Wentai Guo, Donglin Ren, Lin Jin, Xianhan Jiang, and Hui Wang
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Biocompatibility ,Polyesters ,Cell Culture Techniques ,Nanofibers ,Biomedical Engineering ,Pharmaceutical Science ,Medicine (miscellaneous) ,Bioengineering ,Mice ,chemistry.chemical_compound ,Tissue engineering ,Hyaluronic acid ,medicine ,Animals ,General Materials Science ,Lactic Acid ,Hyaluronic Acid ,Cell Proliferation ,Ligaments ,Tissue Engineering ,Tissue Scaffolds ,Mesenchymal stem cell ,medicine.anatomical_structure ,chemistry ,Cell culture ,Nanofiber ,Ligament ,Stem cell ,Biomedical engineering - Abstract
Pelvic organ prolapse (POP) has become one of the most common serious diseases affecting parous women. Weakening of pelvic ligaments plays an essential role in the pathophysiology of POP. Currently, synthetic materials are widely applied for pelvic reconstructive surgery. However, synthetic nondegradable meshes for POP therapy cannot meet the clinical requirements due to its poor biocompatibility. Herein, we fabricated electrospun core–shell nanofibers of poly(l-lactic acid)-hyaluronic acid (PLLA/HA). After that, we combined them with mouse bone marrow-derived mesenchymal stem cells (mBMSCs) to assess the cellular response and pelvic ligament tissue engineering in vitro. The cellular responses on the composite nanofibers showed that the core–shell structure nanofibers displayed with excellent biocompatibility and enhanced cellular activity without cytotoxicity. Moreover, compared with PLLA nanofibers seeded with mBMSCs, PLLA/HA nanofibers exhibited more cellular function, as revealed by the quantitative real-time polymerase chain reaction (RT-qPCR) for pelvic ligament-related gene markers including Col1a1, Col1a3 and Tnc. These features suggested that this novel core–shell nanofiber is promising in stem cell-based tissue engineering for pelvic reconstruction.
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- 2021
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39. Cost-effective fixation of CO2 into cyclic carbonates catalyzed by Zn bromide-based deep eutectic ionic liquid
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Yi Liu, Weilu Ding, Yongzhen Li, Ming Li, Ying Liu, Yunong Li, Qian Su, and Zifeng Yang
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Organic Chemistry ,Drug Discovery ,Biochemistry - Published
- 2023
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40. An ultra-sensitive one-pot RNA-templated DNA ligation rolling circle amplification-assisted CRISPR/Cas12a detector assay for rapid detection of SARS-CoV-2
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Zaobing Zhu, Yongkun Guo, Chen Wang, Zifeng Yang, Rong Li, Zhiqi Zeng, Hui Li, Dabing Zhang, and Litao Yang
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Electrochemistry ,Biomedical Engineering ,Biophysics ,General Medicine ,Biotechnology - Published
- 2023
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41. Network pharmacology associated anti-influenza mechanism research of Qingjie-Tuire Granule via STAT1/3 signaling pathway
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Yutao Wang, Xin Zhao, Mengjie Xiao, Xiaoying Lin, Qiaolian Chen, Shengle Qin, Huihui Ti, and Zifeng Yang
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Multidisciplinary ,Research Article - Abstract
Qingjie-Tuire (QT) granule was approved for clinical use and its combination was reported to treat influenza infection. To explore its active component and mechanism, the components of QT granule were retrieved from UPLC-UC-Q-TOF/MS analysis. The genes corresponding to the targets were retrieved using GeneCards and TTD database. The herb–compound–target network was constructed by Cytoscape. The target protein–protein interaction network was built using STRING database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of QT granule to IAV were performed for further study. The regulation to different signaling transduction events and cytokine/chemokine expression of QT granule was evaluated using Western blotting and real-time qPCR. Totally, 47 compounds were identified and effect of QT granule on cell STAT1/3 signaling pathways was confirmed by A549 cell model. The efficiency of QT granule on host cell contributes to its clinical application and mechanism research.
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- 2023
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42. Scientific guidance to fight the pandemic: the Coronavirus Disease 2019 (COVID-19)
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Nanshan Zhong, Zifeng Yang, Jianxing He, Zhiqi Zeng, and Ke Wang
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Pulmonary and Respiratory Medicine ,2019-20 coronavirus outbreak ,Editorial ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Pandemic ,Medicine ,business ,Virology - Published
- 2021
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43. Nanostructured tubular carbon materials doped with cobalt as electrocatalyst for efficient oxygen reduction reaction
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Jie Cui, An Li, Jingxin Han, Zifeng Yang, Zhaoqi Zhu, Hanxue Sun, and Peilei Zhou
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Nanotube ,Materials science ,020502 materials ,Mechanical Engineering ,chemistry.chemical_element ,02 engineering and technology ,Electrocatalyst ,Catalysis ,chemistry.chemical_compound ,0205 materials engineering ,chemistry ,Polymerization ,Chemical engineering ,Mechanics of Materials ,General Materials Science ,Methanol ,Platinum ,Pyrolysis ,Cobalt - Abstract
The development of non-precious metal catalysts with high efficiency and superior reaction durability for oxygen reduction reaction (ORR) is of great importance for construction of next-generation fuel cells. Herein, we report the preparation of in-situ nitrogen-doped carbon nanotube electrocatalysts (PPy-NCNTs) which were prepared by the pyrolysis of one-dimensional nanotube-like polypyrrole conjugated polymers precursor (PPy-Tubes) synthesized by oxidative polymerization and self-assembly method. The as-prepared PPy-NCNTs show good ORR performance, e.g., its half-wave potential reaches 0.826 V. In order to further improve the ORR performance of PPy-NCNTs, we prepared the Co-N co-doped carbon nanotube materials (Co-N-PPy-NCNTs) with different Co contents by adding cobalt nitrate into the polymerization solution during synthesis of PPy nanotube followed by a pyrolysis treatment. Comparatively, the Co-N-PPy-NCNTs have better ORR performance than that of PPy-NCNTs with a half-wave potential of 0.830 V, a biased 4e− reaction pathway, and better stability and methanol tolerance (high than Pt/C catalysts in the methanol tolerance test and the durability test). Taking advantages of its simple and cost-efficient preparation, high ORR performance and superior stability and methanol tolerance, the Co-N-PPy-NCNTs should be a kind of ideal candidate as an alternative to the precious metal platinum-based catalysts for fuel cells.
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- 2021
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44. Efficient synthesis of isosorbide-based polycarbonate with scalable dicationic ionic liquid catalysts by balancing the reactivity of the endo-OH and exo-OH
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Zhang Zhencai, Zifeng Yang, Weiwei Wang, Yaqin Zhang, Wenjuan Fang, Xu Fei, Donghui Niu, and Hongyan He
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Reaction mechanism ,Isosorbide ,Infrared spectroscopy ,Pollution ,Catalysis ,chemistry.chemical_compound ,chemistry ,Ionic liquid ,medicine ,Environmental Chemistry ,Molar mass distribution ,Imidazole ,Physical chemistry ,Reactivity (chemistry) ,medicine.drug - Abstract
In this study, a series of high-activity imidazole-based dicationic ionic liquids (DILs) were designed and prepared as efficient catalysts for balancing the reactivity between the endo-hydroxyl group (endo-OH) and the exo-hydroxyl group (exo-OH) of isosorbide (ISO) to synthesize high molecular weight poly(isosorbide carbonate) (PIC). Meanwhile, the thermal performance of PIC was precisely optimized by regulating the chain configuration. The results showed that when the trace amounts (4.5 × 10−5 based on the ISO molar amount) of bis-(3-methyl-1-imidazole)-ethylene dibromide ([C2(Min)2][Br]2) were used, the weight average molecular weight (Mw) of PIC reached 98 700 g mol−1. It could be concluded from the results of the experiment and the stimulation that the high catalytic activity of DILs was attributed to the strong electrostatic interaction between the cation and the substrate and the effective balance of the reactivity of the endo-OH and the exo-OH. Furthermore, we found that the reduction of hydroxyl groups in the terminal groups and the increase of endo–endo (a1) structure in the repeating unit improved the thermal properties of PIC. Finally, 1H NMR, Fourier infrared spectroscopy, and density functional theory (DFT) calculations were used to verify the reaction process through anion and cation multi-site synergistic effect and a possible electrophilic–nucleophilic reaction mechanism was successfully obtained.
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- 2021
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45. Synthesis of bio-based polycarbonate via one-step melt polycondensation of isosorbide and dimethyl carbonate by dual site-functionalized ionic liquid catalysts
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Zifeng Yang, Xu Fei, Weiwei Wang, Wenjuan Fang, Xue Li, Suojiang Zhang, Lei Liu, Yongqing Shi, and Zhang Zhencai
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Steric effects ,Isosorbide ,Condensation polymer ,010405 organic chemistry ,Chemistry ,Substrate (chemistry) ,010402 general chemistry ,01 natural sciences ,Pollution ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,Polymer chemistry ,Ionic liquid ,medicine ,Environmental Chemistry ,Dimethyl carbonate ,Selectivity ,medicine.drug - Abstract
The synthesis of green products using renewable bio-monomers has become a research trend with the requirement of sustainable development. In this work, we reported a green pathway to synthesize poly(isosorbide carbonate) (PIC) via one-step melt polycondensation of biomass-derived isosorbide (ISB) and CO2-derived dimethyl carbonate (DMC) catalyzed by eco-friendly dual site-functionalized ionic liquids; a series of these catalysts were synthesized for the first time to the best of our knowledge and their effects on the molecular weight and terminal groups of PIC were systematically investigated. The results showed that the steric structure of cations and anions of catalysts could significantly influence their catalytic performance in polymer synthesis reactions. Meanwhile, it was found that the ability of catalysts to activate the reaction substrate gradually increased with decreasing steric hindrance of cations and anions. Among our exploited ionic liquid catalysts, the selectivity of carboxymethylated products was increased significantly by using bis-tetraethylammonium hydroquinone ([N2222]2 [HQ]), and a PIC with a weight average molecular weight (Mw) of 53 600 along with an ISB conversion up to 99.0% was obtained. As far as we know, the catalyst of [N2222]2 [HQ] was the most efficient catalyst for PIC one-step synthesis compared with the existing traditional ionic liquid catalysts. Besides, according to the detected intermediates of the reaction process and the results of various analytical means, a possible mechanism for the synergetic catalysis of cations–anions promoting the chain growth was proposed.
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- 2021
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46. A paradigm for the efficient synthesis of bio-based polycarbonate with deep eutectic solvents as catalysts by inhibiting the degradation of molecular chains
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Weiwei Wang, Wenjuan Fang, Zifeng Yang, Fei Xu, Yaqin Zhang, Zhang Zhencai, and Hongyan He
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endocrine system ,Depolymerization ,Chemistry ,Hydrogen bond ,Alkalinity ,Transesterification ,biochemical phenomena, metabolism, and nutrition ,Pollution ,Catalysis ,Chemical engineering ,visual_art ,visual_art.visual_art_medium ,Environmental Chemistry ,Synergistic catalysis ,Polycarbonate ,Fourier transform infrared spectroscopy - Abstract
In this study, an efficient catalytic system composed of deep eutectic solvents (DESs) was developed by adjusting the basicity of hydrogen bond donors (HBDs) to synthesize poly(isosorbide) carbonate (PIC) with high weight average molecular weight (Mw). It was demonstrated that the Mw of PIC prepared by using nearly neutral [EminOH]Cl–2EG was the highest. The results of the transesterification kinetics with different catalysts supported that the transesterification rate was significantly promoted as the basicity of DESs increased but their strong alkalinity inhibited the Mw of PIC. Therefore, the degradation of PIC was investigated to reveal the mechanism of the influence of basicity on the molecular weight of PIC. The strong alkalinity of DESs would cause the depolymerization of the macromolecular chains and ultimately limit the molecular weight of the product, proving the experimental fact that a near-neutral catalyst was more conducive to the Mw of PIC. Finally, a reasonable mechanism of synergistic catalysis was proposed based on 1H NMR spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and experimental results. The metal-free, low-cost, high catalytic activity DES catalyst involved here is a practical candidate for advanced bio-based polycarbonate.
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- 2021
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47. Novel Fatty Acid in Cordyceps Suppresses Influenza A (H1N1) Virus-Induced Proinflammatory Response Through Regulating Innate Signaling Pathways
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Jia-Ning Mi, Zhi-Hong Jiang, Xiao Wu, Jian-Jian Qiu, Nanshan Zhong, Haiming Jiang, Run-Feng Li, Zifeng Yang, Wen-Jia Li, Guo-Yuan Zhu, Xiaobo Zhou, Ming Chen, and Hongxia Zhou
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chemistry.chemical_classification ,A549 cell ,Innate immune system ,business.industry ,General Chemical Engineering ,Fatty acid ,General Chemistry ,Lung injury ,Virus ,Proinflammatory cytokine ,Chemistry ,Immune system ,chemistry ,Immunology ,Medicine ,Signal transduction ,business ,QD1-999 - Abstract
Influenza virus (IV) infections usually cause acute lung injury characterized by exaggerated proinflammatory responses. The paucity of therapeutic strategies that target host immune response to attenuate lung injury poses a substantial challenge in management of IV infections. In this study, we chemically synthesized a novel fatty acid (2Z,4E)-deca-2,4-dienoic acid (DDEA) identified from Chinese Cordyceps by using UHPLC-Q-TOF-MS techniques. The DDEA did not inhibit H1N1 virus replication but attenuated proinflammatory responses by reducing mRNA and protein levels of TNF-α, IFN-α, IFN-β, IL-6, CXCL-8/IL-8, CCL-2/MCP-1, CXCL-10/IP-10, CCL-3/MIP-1α, and CCL-4/MIP-1β in A549 cells and U937-derived macrophages. The anti-inflammatory effect occurred through downregulations of TLR-3-, RIG-I-, and type I IFN-activated innate immune signaling pathways. Altogether, our results indicate that DDEA may potentially be used as an anti-inflammatory therapy for the treatment of IV infections.
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- 2021
48. Bisabolane-type sesquiterpenoids fromCurcuma longaL. exert anti-influenza and anti-inflammatory activities through NF-κB/MAPK and RIG-1/STAT1/2 signaling pathways
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Zhitong Mai, Zhoulang Wang, Pang-Chui Shaw, Huihui Ti, Wenjie Zhang, Zifeng Yang, and Mengjie Xiao
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0301 basic medicine ,A549 cell ,MAPK/ERK pathway ,010405 organic chemistry ,medicine.medical_treatment ,NF-κB ,General Medicine ,Pharmacology ,Steroid biosynthesis ,01 natural sciences ,0104 chemical sciences ,Proinflammatory cytokine ,03 medical and health sciences ,chemistry.chemical_compound ,IκBα ,030104 developmental biology ,Cytokine ,chemistry ,medicine ,Signal transduction ,Food Science - Abstract
Influenza is a viral respiratory illness that causes seasonal epidemics and occasional pandemics. Disease severity may be contributed by influenza virus-induced cytokine dysregulation. The study was designed to investigate the isolation and identification of bisabolane-type sesquiterpenoids from Curcuma longa L., their antiviral and anti-inflammatory activities against H1N1 and their potential role in regulating host immune response in vitro. A pair of new bisabolane-type sesquiterpenoids, (6S,7S)-3-hydroxy-3-hydroxymethylbisabola-1,10-diene-9-one (18) together with seventeen known analogs (1–17), was isolated and elucidated from Curcuma longa L. Compounds 2, 11 and 14 could significantly inhibit A/PR/8/34 (H1N1) replication in MDCK cells, and compound 2 could significantly inhibit A/PR/8/34 (H1N1) replication in A549 cells. Compounds 4, 8, 9, 13 and 17 could markedly reduce pro-inflammatory cytokine (TNF-α, IL-6, IL-8 and IP-10) production at the mRNA and protein levels in A549 cells. Compound 4 regulated the levels of steroid biosynthesis, oxidative phosphorylation and protein processing in the endoplasmic reticulum, thereby inhibiting immune responses by proteomics analysis. Furthermore, compound 4 could inhibit the expression of p-NF-κB p65, NF-κB p65, IκBα, p-p38 MAPK, p-IκBα, RIG-1, STAT-1/2 and p-STAT-1/2 in the signaling pathways. These findings indicate that bisabolane-type sesquiterpenoids of C. longa could inhibit the expression of inflammatory cytokines induced by the virus and regulate the activity of NF-κB/MAPK and RIG-1/STAT-1/2 signaling pathways in vitro.
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- 2021
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49. One-pot synthesis of isosorbide-based copolycarbonate with good flexibility and tunable thermal property
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Wenjuan Fang, Mengqian Fu, Zhang Zhencai, Zifeng Yang, Weiwei Wang, Fei Xu, Chenhao Li, and Yongqing Shi
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Flexibility (engineering) ,Isosorbide ,Materials science ,Condensation polymer ,Polymers and Plastics ,One-pot synthesis ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Thermal ,Materials Chemistry ,Ceramics and Composites ,medicine ,Dimethyl carbonate ,0210 nano-technology ,medicine.drug - Abstract
In this article, we reported a new strategy to synthesize of isosorbide-based copolycarbonates with good flexibility and tunable thermal property via one-pot direct melt polycondensation of isosorbide (ISB), dimethyl carbonate (DMC) and 1,4-benzenedimethanol (BDM). The effect of different feed ratio on the chemical structure, molecular weight, thermal and mechanical property of copolycarbonates was in-depth studied. A series of metal ion-containing compounds as catalysts were used, and the copolycarbonates was synthesized with weight average molecular weight (Mw) of 80,300 and dispersity index below 1.78 by sodium tert-butoxide catalyst, and the reaction time was shorted to only 3.5 h with the ISB conversion up to 99.0%. Meanwhile, the Tg values realized controllable and tunable from 69 to 164 °C by varying the ratio of two diol monomers, and the influence of the structure of carbonyl carbon in repeating units of copolycarbonates on the thermal properties were demonstrated. Moreover, the results of dynamic mechanical analysis (DMA) implied that the flexibility of copolycarbonates was increased with increasing BDM content, and the results of scratch resistance and melting index of the copolycarbonates provided enormous prospect for the industrial application. Synopsis: A green synthetic pathway for high molecular weight and flexible isosorbide-based copolycarbonate was developed via one-pot melt polycondensation of isosorbide, dimethyl carbonate and 1,4-benzenedimethanol.
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- 2020
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50. Aculeatusane A: A new diterpenoid from the whole plants of Celastrus aculeatus Merr
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Lee-Fong Yau, Cheng-Yu Chen, Zhi-Hong Jiang, Guo-Yuan Zhu, Jing-Rong Wang, Zhi-Tong Mai, Zifeng Yang, and Run-Feng Li
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Celastraceae ,biology ,Chemistry ,Stereochemistry ,Plant Science ,biology.organism_classification ,Celastrus aculeatus ,Agronomy and Crop Science ,Biochemistry ,Terpenoid ,Biotechnology - Abstract
A new podocarpane type diterpenoid, aculeatusane A (1), and six known diterpenoids (2-7) were isolated from the whole plants of Celastrus aculeatus Merr. (Celastraceae). The structures were identified based on the HRESIMS and NMR spectroscopic data. All diterpenoids were isolated from C. aculeatus for the first time. Antiviral activity assay showed that aculeatusane A (1) is active against A/GZ/GIRD07/09 (H1N1) with the selectivity index (SI) of 6.75 ± 4.38.
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- 2020
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