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He Y, Yang Y, Huang H, Yang W, Ren B, Hu Q, Jin J, Wen S, Cheng H, Shen L. Spatio-temporal variations in activity of aerobic methane oxidation and community structure of methanotrophs in sediment of Wuxijiang river. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 363:125200. [PMID: 39461609 DOI: 10.1016/j.envpol.2024.125200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2024] [Revised: 10/13/2024] [Accepted: 10/23/2024] [Indexed: 10/29/2024]
Abstract
Rivers are hotspots for methane (CH4) emissions, and aerobic methane oxidation is a crucial process in controlling emissions. The spatio-temporal heterogeneity of river environment can greatly affect the methane oxidation process. However, currently, few studies have focused on the spatio-temporal changes in activity of methane oxidation and the associated microbiome in riverine ecosystems, which hinders a comprehensive understanding the role of this process in reducing emissions of CH4. Here, we investigated the variations in methane oxidation activity and community of methanotrophs in sediment of a mountain river across different reaches and seasons. The potential methane oxidation rate ranged from 24.11 to 493.03 nmol CH4 g-1 (sediment) d-1, which was significantly greater in sediment obtained during the winter than in that obtained during the summer. Moreover, the rate in middle reaches was significantly greater than that in upper and lower reaches in summer. The abundance of pmoA gene of methanotrophs ranged from 2.45 × 10⁶ to 2.98 × 10⁷ copies g-1 (sediment), which was also significantly greater in winter than in summer and showed significant variations among reaches. Additionally, methanotrophic diversity and community composition exhibited significant variations across both reaches and seasons, and the relative abundance of Methylococcus and Methylocystis was closely associated with methane oxidation activity. Sediment NH4+ content, pH and temperature were potentially crucial factors affecting the activity or methanotrophic community. In conclusion, it is necessary to consider both temporal and spatial scales to improve our understanding of the significance and driving mechanisms of methane oxidation in controlling CH4 emissions from rivers.
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Shen L, He Y, Hu Q, Yang Y, Ren B, Yang W, Geng C, Jin J, Bai Y. Vertical distribution of Candidatus Methylomirabilis and Methanoperedens in agricultural soils. Appl Microbiol Biotechnol 2024; 108:47. [PMID: 38175239 DOI: 10.1007/s00253-023-12876-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/04/2023] [Accepted: 10/16/2023] [Indexed: 01/05/2024]
Abstract
Candidatus Methylomirabilis-related bacteria conduct anaerobic oxidation of methane (AOM) coupling with NO2- reduction, and Candidatus Methanoperedens-related archaea perform AOM coupling with reduction of diverse electron acceptors, including NO3-, Fe (III), Mn (IV) and SO42-. Application of nitrogen fertilization favors the growth of these methanotrophs in agricultural fields. Here, we explored the vertical variations in community structure and abundance of the two groups of methanotrophs in a nitrogen-rich vegetable field via using illumina MiSeq sequencing and quantitative PCR. The retrieved Methylomirabilis-related sequences had 91.12%-97.32% identity to the genomes of known Methylomirabilis species, and Methanoperedens-related sequences showed 85.49%-97.48% identity to the genomes of known Methanoperedens species which are capable of conducting AOM coupling with reduction of NO3- or Fe (III). The Methanoperedens-related archaeal diversity was significantly higher than Methylomirabilis-related bacteria, with totally 74 and 16 operational taxonomic units, respectively. In contrast, no significant difference in abundance between the bacteria (9.19 × 103-3.83 × 105 copies g-1 dry soil) and the archaea (1.55 × 104-3.24 × 105 copies g-1 dry soil) was observed. Furthermore, the abundance of both groups of methanotrophs exhibited a strong vertical variation, which peaked at 30-40 and 20-30 cm layers, respectively. Soil water content and pH were the key factors influencing Methylomirabilis-related bacterial diversity and abundance, respectively. For the Methanoperedens-related archaea, both soil pH and ammonium content contributed significantly to the changes of these archaeal diversity and abundance. Overall, we provide the first insights into the vertical distribution and regulation of Methylomirabilis-related bacteria and Methanoperedens-related archaea in vegetable soils. KEY POINTS: • The archaeal diversity was significantly higher than bacterial. • There was no significant difference in the abundance between bacteria and archaea. • The abundance of bacteria and archaea peaked at 30-40 and 20-30 cm, respectively.
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Li S, Zhang Z, Xie L, Zhao Y, Chen H, Zhang S, Cai Y, Ren B, Liu W, Tang S, Sha Y. Novel bi-allelic DNAH3 variants cause oligoasthenoteratozoospermia. Front Endocrinol (Lausanne) 2024; 15:1462509. [PMID: 39588341 PMCID: PMC11586517 DOI: 10.3389/fendo.2024.1462509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2024] [Accepted: 09/25/2024] [Indexed: 11/27/2024] Open
Abstract
Background Oligoasthenoteratozoospermia (OAT) is a widespread cause of male infertility. One of the usual clinical manifestations of OAT is multiple morphological abnormalities of the sperm flagella (MMAF), which are frequently associated with mutations and defects in the dynein family. However, the relationship between the newly identified Dynein Axonemal Heavy Chain 3 (DNAH3) mutation and oligonasthenospermia in humans has not yet been established. Methods Whole exome sequencing, pathogenicity analysis, and species conservation analysis of mutation sites were conducted on two patients from different unrelated families with DNAH3 mutations. We identified representative mutation sites and predicted the protein structure following these mutations. The sperm characteristics of the two patients with DNAH3 mutations were verified using Papanicolaou staining, scanning electron microscopy, and transmission electron microscopy. Additionally, mRNA and protein levels were assessed through RT-qPCR and Western blotting. Results The biallelic mutations in the first progenitor included a heterozygous deletion and insertion, c.6535_6536 delinsAC (to infect mutation (p.Asp2179Thr), and stop codon premutation, c.3249G > A (p.Trp1083Ter). In Family II, the patient (P2) harbored a DNAH3 heterozygous missense mutation, c. 10439G> A(p.Arg3480Gln), along with a stop codon premutation, (c.10260G > A; p.Trp3420Ter). Patients with premature termination of transcription or translation due to DNAH3 mutations exhibit OAT phenotypes, including fibrous sheath dysplasia and multiple tail malformations. We identified the representative sites after mutation, predicted the protein structure, and assessed changes in the protein levels of DNAH3 and related genes following mutations. Notably,a significant reduction in DNAH3 protein expression was validated in these patients. We may explore in the future how DNAH3 affects sperm motility and quality through regulatory mechanisms involving protein structural changes. Conclusion Novel biallelic mutations in DNAH3, especially those resulting in a premature stop codon, may alter protein expression, structure, and active site, leading to spermatogenic failure and potentially inducing OAT. The discovery of new mutations in DNAH3 may be the key to the diagnosis and treatment of OAT.
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Yang Y, Shen L, Agathokleous E, Wang S, Jin Y, Bai Y, Yang W, Ren B, Jin J, Zhao X. The interplay of soil physicochemical properties, methanogenic diversity, and abundance governs methane production potential in paddy soil subjected to multi-decadal straw incorporation. ENVIRONMENTAL RESEARCH 2024; 256:119246. [PMID: 38810824 DOI: 10.1016/j.envres.2024.119246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 05/20/2024] [Accepted: 05/26/2024] [Indexed: 05/31/2024]
Abstract
Straw incorporation holds significant promise for enhancing soil fertility and mitigating air pollution stemming from straw burning. However, this practice concurrently elevates the production and emission of methane (CH4) from paddy ecosystems. Despite its environmental impact, the precise mechanisms behind the heightened CH4 production resulting from long-term straw incorporation remain elusive. In a 32-year field experiment featuring three fertilization treatments (CFS-chemical fertilizer with wheat straw, CF-chemical fertilizer, and CK-unamended), we investigated the impact of abiotic (soil physicochemical properties) and biotic (methanogenic abundance, diversity, and community composition) factors on CH4 production in paddy fields. Results revealed a significantly higher CH4 production potential under CFS treatment compared to CF and CK treatments. The partial least squares path model revealed that soil physicochemical properties (path coefficient = 0.61), methanogenic diversity (path coefficient = -0.43), and methanogenic abundance (path coefficient = 0.29) collectively determined CH4 production potential, explaining 77% of the variance. Enhanced soil organic carbon content and water content, resulting from straw incorporation, emerged as pivotal factors positively correlated with CH4 production potential. Under CFS treatment, lower Shannon index of methanogens, compared to CF and CK treatments, was attributed to increased Methanosarcina. Notably, the Shannon index and relative abundance of Methanosarcina exhibited negative and positive correlations with CH4 production potential, respectively. Methanogenic abundance, bolstered by straw incorporation, significantly amplified overall potential. This comprehensive analysis underscores the joint influence of abiotic and biotic factors in regulating CH4 production potential during multi-decadal straw incorporation.
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Xu Z, Liu Y, Song B, Ren B, Xu X, Lin R, Zhu X, Chen C, Yang S, Zhu Y, Jiang W, Li W, Xia Y, Hu L, Chen S, Chan CC, Li J, Zhang X, Yang L, Tian X, Ding CZ. Discovery and preclinical evaluations of TQB3616, a novel CDK4-biased inhibitor. Bioorg Med Chem Lett 2024; 107:129769. [PMID: 38670537 DOI: 10.1016/j.bmcl.2024.129769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/12/2024] [Accepted: 04/23/2024] [Indexed: 04/28/2024]
Abstract
Among small-molecule CDK4/6 inhibitors (palbociclib, ribociclib, and abemaciclib) approved for metastatic breast cancers, abemaciclib has a more tolerable adverse effects in clinic. This is attributable to preferential inhibition of CDK4 over CDK6. In our search for a biased CDK4 inhibitor, we discovered a series of pyrimidine-indazole inhibitors. SAR studies led us to TQB3616 as a preferential CDK4 inhibitor. TQB3616 exhibited improvements in both enzymatic and cellular proliferation inhibitory potency when tested side-by-side with the FDA approved palbociclib and abemaciclib. TQB3616 also possessed favorable PK profile in multiple species. These differentiated properties, together with excellent GLP safety profile warranted TQB3616 moving to clinic. TQB3616 entered into clinical development in 2019 and currently in phase III clinical trials (NCT05375461, NCT05365178).
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Wang M, Li Q, Ren B, Hao D, Guo H, Yang L, Wang Z, Dai L. Ethanolic extract of Arctium lappa leaves alleviates cerebral ischemia reperfusion-induced inflammatory injury via HDAC9-mediated NF-κB pathway. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 129:155599. [PMID: 38669967 DOI: 10.1016/j.phymed.2024.155599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/18/2024] [Accepted: 04/06/2024] [Indexed: 04/28/2024]
Abstract
BACKGROUND Ischemic stroke (IS) is a major cause of mortality and disability worldwide. Inflammatory response is crucial in the pathogenesis of tissue injury in cerebral infarction. Arctium lappa leaves are traditionally used to treat IS. PURPOSES To investigate the neuroprotective effects and molecular mechanisms of the ethanolic extract of A. lappa leaves (ALLEE) on cerebral ischemia-reperfusion (CIR). METHODS Middle cerebral artery obstruction reperfusion (MCAO/R) rats and an oxygen-glucose deprivation/reoxygenation (OGD/R) cell model were used to evaluate ALLEE pharmacodynamics. Various methods, including neurological function, 2,3,5-triphenyltetrazolium chloride, hematoxylin and eosin, and Nissl, enzyme-linked immunosorbent, and TdT-mediated dUTP nick-end labeling assays, were used to analyze the neuroprotective effects of ALLEE in vitro and in vivo. The major chemical components and potential target genes of ALLEE were screened using network pharmacology. Molecular docking, western blotting, and immunofluorescence analyses were performed to confirm the effectiveness of the targets in related pathways. RESULTS ALLEE exerted potent effects on the MCAO/R model by decreasing the neurological scores, infarct volumes, and pathological features (p < 0.01). Furthermore, network pharmacology results revealed that the treatment of IS with ALLEE involved the regulation of various inflammatory pathways, such as the tumor necrosis factor (TNF) and chemokine signaling pathways. ALLEE also played key roles in targeting key molecules, including nuclear factor (NF)-κBIA, NF-κB1, interleukin (IL)-6, TNF-α and IL1β, and regulating the histone deacetylase (HDAC)-9-mediated signaling pathway. In vivo and in vitro analyses revealed that ALLEE significantly regulated the NF-κB pathway, promoted the phosphorylation activation of NF-κB P65, IκB and IKK (p < 0.01 or p < 0.05), and decreased the expression levels of the inflammatory factors, IL-1β, IL-6 and TNF-α (p < 0.01). Moreover, ALLEE significantly decreased the expression of HDAC9 (p < 0.01) that is associated with inflammatory responses. However, HDAC9 overexpression partially reversed the neuroprotective effects of ALLEE and its suppressive effects on inflammation and phosphorylation of NF-κB (p < 0.01). CONCLUSIONS In conclusion, our results revealed that ALLEE ameliorates MCAO/R-induced experimental CIR by modulating inflammatory responses via the inhibition of HDAC9-mediated NF-κB pathway.
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Bai Y, Wang Y, Shen L, Shang B, Ji Y, Ren B, Yang W, Yang Y, Ma Z, Feng Z. Equal importance of humic acids and nitrate in driving anaerobic oxidation of methane in paddy soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169311. [PMID: 38103608 DOI: 10.1016/j.scitotenv.2023.169311] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 12/08/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
Methane (CH4) is both generated and consumed in paddy soils, where anaerobic oxidation of methane (AOM) serves as a crucial process for mitigating CH4 emissions. Although the participation of humic acids (HA) and nitrate in AOM has been recognized, their relative roles and significance in paddy soils remain insufficiently investigated. In this study, we explored the potential activity of AOM driven by HA and nitrate, as well as the composition of archaeal communities in paddy soils across different rice growth periods and fertilization treatments. AOM activity ranged from 0.81 to 1.33 and 1.26 to 2.38 nmol of 13CO2 g-1 (dry soil) day-1 with HA and nitrate, respectively. No significant differences (p < 0.05) were observed between the AOM activity driven by HA and nitrate across the three fertilization treatments. According to AOM activity, the annual consumption of CH4 was estimated at approximately 0.49 ± 0.06 and 0.83 ± 0.19 Tg for AOM processes driven by HA and nitrate in Chinese paddy soils. Nitrate-driven AOM activity exhibited a positive (p < 0.05) correlation with the abundance of the ANME-2d mcrA gene but a negative (p < 0.05) correlation with the content of dissolved organic carbon. Intriguingly, HA-driven AOM activity was only correlated positively with the nitrate-driven AOM activity. Soil water content, soil organic carbon, nitrate and nitrite contents were significantly correlated with the relative abundance of methanogenic and methanotrophic archaea. These results identified the potential importance of HA and nitrate in driving AOM processes within paddy soils, providing a comprehensive understanding of the complex microbial processes regulating greenhouse gas emissions from paddy soils.
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Ren B, Wang W, Shen L, Yang W, Yang Y, Jin J, Geng C. Nitrogen fertilization rate affects communities of ammonia-oxidizing archaea and bacteria in paddy soils across different climatic zones of China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166089. [PMID: 37549709 DOI: 10.1016/j.scitotenv.2023.166089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 08/02/2023] [Accepted: 08/04/2023] [Indexed: 08/09/2023]
Abstract
Nitrogen fertilization has important effects on nitrification. However, how the rate of nitrogen fertilization affects nitrification potential, as well as the communities of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB), remains unclear. We performed a large-scale investigation of nitrification potential and ammonia-oxidizer communities in Chinese paddy fields at different nitrogen fertilization rates across different climatic zones. It was found that the nitrification potential at the high nitrogen fertilization rate (≥150 kg-1 N ha-1) was 23.35 % higher than that at the intermediate rate (100-150 kg-1 N ha-1) and 20.77 % higher than that at the low rate (< 100 kg-1 N ha-1). The nitrification potential showed no significant variation among different nitrogen fertilization rates across climatic zones. Furthermore, the AOA and AOB amoA gene abundance at the high nitrogen fertilization rate was 481.67 % and 292.74 % higher (p < 0.05) than that at the intermediate rate, respectively. Correlation analysis demonstrated a significant positive correlation between AOB abundance and nitrification potential. AOA and AOB community composition differed significantly among nitrogen fertilization rates. Moreover, soil NH4+ content, pH, water content, bulk density, and annual average temperature were regarded as key environmental factors influencing the community structure of ammonia-oxidizers. Taken together, the nitrogen fertilization rate had a significant impact on the communities of AOA and AOB but did not significantly alter the nitrification potential. Our findings provide new insights into the impact of nitrogen fertilization management on nitrification in rice paddy fields.
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Li YQ, Peng X, Ren B, Yan FH, Pan YP, Chen F, Du WB, Liu JG, Feng Q, Yang DQ, Huang XJ, Pan YH, Huang ZZ, Ding PH, Zhang KK, Liu HX, Zhou XD. [Standardized nomenclature of oral microorganisms in Chinese: the 2023 update]. ZHONGHUA KOU QIANG YI XUE ZA ZHI = ZHONGHUA KOUQIANG YIXUE ZAZHI = CHINESE JOURNAL OF STOMATOLOGY 2023; 58:1051-1061. [PMID: 37730417 DOI: 10.3760/cma.j.cn112144-20230816-00079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
Oral microbial community, as an important part of human microbial community, is closely related to oral and general health. Oral microbiological research has become the forefront of international microbiological research. Standardized and unified nomenclature for oral microorganisms in Chinese is of great significance to support the development of oral medicine research. Standardized translation of microbial names is the basis for writing canonical and authoritative professional textbooks and reference books, which helps students to accurately acquire the characteristics and classifications of oral microbes. Unified translation of oral microorganisms is also conducive to academic communication and cooperation, and plays an important role in oral health education and science popularization, which enables oral microbiology knowledge to be accurately disseminated to the public. Therefore, in order to standardize the words in scientific research, funding application, publications, academic exchanges and science popularization within the field of oral medicine, we have fully discussed and revised the Chinese names of oral microorganisms in 2017 edition and ones of newly discovered oral microbes, finally reaching a consensus to form the 2023 edition of Chinese names of oral microorganisms.
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Huang Y, Han Q, Peng X, Ren B, Li J, Zhou X, Li M, Cheng L. Disaggregated Nano-Hydroxyapatite (DnHAP) with Inhibitory Effects on Biofilms and Demineralization. J Dent Res 2023:220345231162349. [PMID: 37283034 DOI: 10.1177/00220345231162349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Abstract
Nano-hydroxyapatite (nHAP) is considered a biocompatible agent that promotes the remineralization of dental hard tissue; however, its antibacterial efficacy is under scientific discussion. Therefore, this investigation aimed to specify the inhibitory effects of disaggregated nano-hydroxyapatite (DnHAP) on regrown biofilms and demineralization. Regrown biofilm models of single-species (Streptococcus mutans), dual-species (S. mutans and Candida albicans), and saliva-derived microcosm biofilms were established in vitro. Repeat treatment with DnHAP was applied to biofilms. The viability, lactic acid, biofilm structure, biomass, the inhibitory effect of demineralization, and virulence factors' expression were determined. In addition, the biofilm microbial community was analyzed by 16S ribosomal RNA gene sequencing. DnHAP inhibited metabolism, lactic acid production, biomass, and water-insoluble polysaccharide production (P < 0.05) of regrown single/dual-species biofilms. Concerning the saliva-derived biofilms, samples treated with DnHAP showed lower biofilm metabolic activity without significant differences from samples treated with sterile deionized water (P > 0.05); in addition, saliva-derived biofilms treated with DnHAP exhibited lower lactic acid production (P < 0.05). The demineralization of bovine enamel was the lowest in the DnHAP group, as detected by transverse microradiography, and the lesion depth and volume decreased significantly (P < 0.05). The application of DnHAP did not change the diversity of regrown saliva-derived microcosm biofilms. In conclusion, this investigation showed that DnHAP could be a promising solution for the management of regrown biofilms to combat dental caries.
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Cheng H, Yang Y, He Y, Zhan X, Liu Y, Hu Z, Huang H, Yao X, Yang W, Jin J, Ren B, Liu J, Hu Q, Jin Y, Shen L. Spatio-temporal variations of activity of nitrate-driven anaerobic oxidation of methane and community structure of Candidatus Methanoperedens-like archaea in sediment of Wuxijiang river. CHEMOSPHERE 2023; 324:138295. [PMID: 36893867 DOI: 10.1016/j.chemosphere.2023.138295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 03/01/2023] [Accepted: 03/02/2023] [Indexed: 06/18/2023]
Abstract
Nitrate-driven anaerobic oxidation of methane (AOM), catalyzing by Candidatus Methanoperedens-like archaea, is a new addition in the global CH4 cycle. This AOM process acts as a novel pathway for CH4 emission reduction in freshwater aquatic ecosystems; however, its quantitative importance and regulatory factors in riverine ecosystems are nearly unknown. Here, we examined the spatio-temporal changes of the communities of Methanoperedens-like archaea and nitrate-driven AOM activity in sediment of Wuxijiang River, a mountainous river in China. These archaeal community composition varied significantly among reaches (upper, middle, and lower reaches) and between seasons (winter and summer), but their mcrA gene diversity showed no significant spatial or temporal variations. The copy numbers of Methanoperedens-like archaeal mcrA genes were 1.32 × 105-2.47 × 107 copies g-1 (dry weight), and the activity of nitrate-driven AOM was 0.25-1.73 nmol CH4 g-1 (dry weight) d-1, which could potentially reduce 10.3% of CH4 emissions from rivers. Significant spatio-temporal variations of mcrA gene abundance and nitrate-driven AOM activity were found. Both the gene abundance and activity increased significantly from upper to lower reaches in both seasons, and were significantly higher in sediment collected in summer than in winter. In addition, the variations of Methanoperedens-like archaeal communities and nitrate-driven AOM activity were largely impacted by the sediment temperature, NH4+ and organic carbon contents. Taken together, both time and space scales need to be considered for better evaluating the quantitative importance of nitrate-driven AOM in reducing CH4 emissions from riverine ecosystems.
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Shen L, Ren B, Jin Y, Liu X, Jin J, Huang H, Tian M, Yang W, Yang Y, Liu J, Geng C, Bai Y, Hu Z. Effects of abrupt and gradual increase of atmospheric CO 2 concentration on methanotrophs in paddy fields. ENVIRONMENTAL RESEARCH 2023; 223:115474. [PMID: 36773639 DOI: 10.1016/j.envres.2023.115474] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/27/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
The simulation of abrupt atmospheric CO2 increase is a common way to examine the response of soil methanotrophs to future climate change. However, atmosphere is undergoing a gradual CO2 increase, and it is unknown whether the previously reported response of methanotrophs to abrupt CO2 increase can well represent their response to the gradual increase. To improve the understanding of the effect of elevated CO2 (eCO2) on methanotrophs in paddy ecosystems, the methane oxidation potential and communities of methanotrophs were examined via open top chambers under the three following CO2 treatments: an ambient CO2 concentration (AC); an abrupt CO2 increase by 200 ppm above AC (AI); a gradual CO2 increase by 40 ppm each year until 200 ppm above AC (GI). Relative to AC treatment, AI and GI treatments significantly (p < 0.05) increased the methane oxidation rate by 43.8% and 36.7%, respectively, during rice growth period. Furthermore, the abundance of pmoA genes was significantly (p < 0.05) increased by 62.4% and 32.5%, respectively, under AI and GI treatments. However, there were no significant variations in oxidation rate or gene abundance between the two eCO2 treatments. In addition, no obvious change of overall community composition of methanotrophs was observed among treatments, while the proportions of Methylosarcina and Methylocystis significantly (p < 0.05) changed. Taken together, our results indicate similar response of methanotrophs to abrupt and gradual CO2 increase, although the magnitude of response under gradual increase was smaller and the abrupt increase may somewhat overestimate the response.
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Yu G, Zhao T, Ren B. The Dead-Reckoning Navigation Guidance Law Based on Neural Network Collaborative Forecasting. INT J ARTIF INTELL T 2022. [DOI: 10.1142/s021821302350015x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Cheng H, Yang Y, Shen L, Liu Y, Zhan X, Hu Z, Huang H, Jin J, Ren B, He Y, Jin Y, Su Z. Spatial variations of activity and community structure of nitrite-dependent anaerobic methanotrophs in river sediment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 851:158288. [PMID: 36030855 DOI: 10.1016/j.scitotenv.2022.158288] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/19/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Rivers are an important site for methane emissions and reactive nitrogen removal. The process of nitrite-dependent anaerobic methane oxidation (n-damo) links the global carbon cycle and the nitrogen cycle, but its role in methane mitigation and nitrogen removal in rivers is poorly known. In the present study, we investigated the activity, abundance, and community composition of n-damo bacteria in sediment of the upper, middle, and lower reaches of Wuxijiang River (Zhejiang Province, China). The 13CH4 stable isotope experiments showed that the methane oxidation activity of n-damo was 0.11-1.88 nmol CO2 g-1 (dry sediment) d-1, and the activity measured from the middle reaches was significantly higher than that from the remaining regions. It was estimated that 3.27 g CH4 m-2 year-1 and 8.72 g N m-2 year-1 could be consumed via n-damo. Quantitative PCR confirmed the presence of n-damo bacteria, and their 16S rRNA gene abundance varied between 5.45 × 105 and 5.86 × 106 copies g-1 dry sediment. Similarly, the abundance of n-damo bacteria was significantly higher in the middle reaches. High-throughput sequencing showed a high n-damo bacterial diversity, with totally 152 operational taxonomic units being detected at 97 % sequence similarity cut-off. In addition, the n-damo bacterial community composition also varied spatially. The inorganic nitrogen (NH4+, NO2-, NO3-) level was found to be the key environmental factor controlling the n-damo activity and bacterial community composition. Overall, our results showed the spatial variations and environmental regulation of the activity and community structure of n-damo bacteria in river sediment, which expanded our understanding of the quantitative importance of n-damo in both methane oxidation and reactive nitrogen removal in riverine systems.
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Yang Y, Ren B, Bian X, Li D, Xu C, Shi F, Zhao J, Tao M, Liang R. Effect of palliative microwave ablation on metastatic osseous pain: a single-center retrospective study. ANNALS OF PALLIATIVE MEDICINE 2021; 10:9725-9731. [PMID: 34628898 DOI: 10.21037/apm-21-2164] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/10/2021] [Indexed: 11/06/2022]
Abstract
BACKGROUND Bone is among the most common metastasis sites in patients with advanced cancer. Approximately two-thirds of bone metastasis results in pain, the majority of which is moderate to unbearable pain, which seriously affects the quality of life of patients. With the development of ablation techniques, microwave ablation (MWA) has great potential to eliminate the pain caused by bone metastasis. This study aimed to evaluate the efficacy and safety of image-guided (computed tomography-guided) percutaneous MWA for metastatic osseous pain. METHODS This is a retrospective study involving 18 patients with cancer-related pain caused by osseous or soft tissue metastasis in the First Affiliated Hospital of Soochow University from June 2015 to October 2020. All patients (14 men and 4 women; mean age 60.2 years) underwent image-guided percutaneous palliative MWA. A paired-sample t-test was used to compare the changes in Numeric Rating Scale (NRS) score and dosage of morphine preoperatively and postoperatively (at 24 h, 3 days, and 14 days after MWA). In addition, we assessed the level of pain relief according to the patients' subjective feelings. RESULTS The paired-samples t-test showed that the NRS score (6.83±0.92 vs. 1.67±0.97, P<0.05) and dosage of morphine (85.56±17.23 vs. 32.78±4.61, P<0.05) were significantly decreased at 3 days after MWA. At 14 days after MWA, the NRS score (6.83±0.92 vs. 0.94±0.87, P<0.05) and dosage of morphine (85.56±17.23 vs. 10.56±8.73, P<0.05) were also markedly decreased. Moreover, according to the patients' subjective feeling, 88.89% patients had pain relief postoperatively, while the remaining patients had no progress. CONCLUSIONS Image-guided (Computed Tomography-guided) percutaneous MWA can effectively relieve pain, thus improving the quality of life in patients with osseous metastasis. MWA is a feasible, safe, and effective treatment for pain caused by bone metastasis.
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Zhang X, Zhang L, Ren B, Tang X, Liu H, Wang Y, Zhang Z, Zhao J. P57.13 Correlation of TP53/KMT2C co-mutation and Tumor Microenvironment in Lung Cancer. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Fu GQ, Fang Y, Yao JJ, Ren B, Zan XF, Liu EL, Chen MJ. TWO MIXED-LIGAND Cu(II) COORDINATION POLYMERS: PROTECTIVE EFFECT ON SEPSIS BY REDUCING
AN EXCESSIVE INFLAMMATORY RESPONSE. J STRUCT CHEM+ 2021. [DOI: 10.1134/s0022476621050176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Ooms JF, Geleijnse ML, Spitzer E, Ren B, Van Wiechen MP, Hokken TW, Daemen J, de Jaegere PPT, Van Mieghem NMDA. Transcatheter mitral valve repair in proportionate and disproportionate functional mitral regurgitation-insights from a small cohort study. Neth Heart J 2021; 29:359-364. [PMID: 34105050 PMCID: PMC8271066 DOI: 10.1007/s12471-021-01583-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2021] [Indexed: 11/30/2022] Open
Abstract
Background Functional mitral regurgitation (FMR) can be subclassified based on its proportionality relative to left ventricular function and end-diastolic volume. FMR proportionality could help identify responders to transcatheter edge-to-edge mitral valve repair (MitraClip) in terms of residual FMR and/or clinical improvement. Methods This single-centre retrospective cohort study evaluated the feasibility of determining FMR proportionality in symptomatic heart failure patients with reduced left ventricular function who were treated with MitraClip for ≥ moderate-to-severe FMR. Baseline proportionate (pFMR) and disproportionate FMR (dFMR) were distinguished. Patient characteristics and MitraClip procedural outcomes were described. Results From an overall cohort of 81 eligible FMR patients, 23/81 (28%) had to be excluded due to missing transthoracic echocardiogram parameters, 22/81 were excluded based on FMR severity. The remaining cohort, of 36/81 patients (44%), could be classified into dFMR (n = 26) or pFMR (n = 10). Conduction disorders were numerically increased in dFMR. All cases requiring > 2 clips were in the dFMR group and absence of FMR reduction occurred more frequently with dFMR. Point of view/Conclusion Important limitations in terms of imaging acquisition affect the translation of the FMR proportionality concept to a real-world data set. We did observe different demographic and FMR response patterns in patients with proportionate and disproportionate FMR that warrant further investigation. Supplementary Information The online version of this article (10.1007/s12471-021-01583-6) contains supplementary material, which is available to authorized users.
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Ren B, Wan S, Liu L, Qu M, Wu H, Shen H. Distributions of serum thyroid-stimulating hormone in 2020 thyroid disease-free adults from areas with different iodine levels: a cross-sectional survey in China. J Endocrinol Invest 2021; 44:1001-1010. [PMID: 32816248 DOI: 10.1007/s40618-020-01395-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 08/13/2020] [Indexed: 01/09/2023]
Abstract
PURPOSE The aim of the present study was to describe the distributions of serum thyroid- stimulating hormone (TSH) levels in thyroid disease-free adults from areas with different iodine levels in China. Meanwhile, we aimed to evaluate the influence of age and gender on the distribution of TSH, assess the relationship between concentrations of TSH and free thyroxine (FT4), and analyze the factors that may affect TSH levels. METHODS 2020 adults were included from April 2016 to June 2019. Urinary iodine concentration, serum iodine concentration, serum TSH, FT4, free triiodothyronine, thyroid peroxidase antibodies and thyroglobulin antibodies were measured, and thyroid ultrasonography was performed. RESULTS The median of TSH in iodine-fortification areas (IFA), iodine-adequate areas (IAA), iodine-excessive areas (IEA) were 2.32, 2.11 and 2.34 mIU/L, respectively. Serum TSH concentrations were significantly higher in IFA and IEA than that in IAA (p = 0.005 and < 0.0001). The TSH values of most adults were distributed within the range of 1.01-3.00 mIU/L with the same trend in three groups. In our study, TSH levels did not change with age, and the TSH level of females was higher than that of males (p < 0.0001). There was a negative correlation between FT4 and TSH in IAA (r = - 0.160, p < 0.0001) and IEA (r = - 0.177, p < 0.0001), but there was no correlation between FT4 and TSH in IFA (r = - 0.046, p = 0.370). BMI, smoking status, education levels, and marital status were associated with TSH. CONCLUSION Our study provides a basis for establishing the reference intervals of TSH in different iodine level areas.
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Ren B, Dang Y, Gan FJ, Yang P. CFD simulation of subcooled boiling flow in PWR 5 ⨯ 5 rod bundle. KERNTECHNIK 2021. [DOI: 10.1515/kern-2020-0061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
This paper describes the computational fluid dynamics (CFD) methodology to simulate the boiling flow in a typical Pressurized Water Reactor (PWR) 5 ⨯ 5 rod bundle. The method includes the Eulerian-Eulerian two-fluid model coupled with the improved wall heat partitioning model. The NUPEC PWR Subchannel and Bundle Test (PSBT) International Benchmark are used for validation. The simulated surface averaged void fraction agree well with the experimental data, which indicate the promising application of the present method for modeling the boiling flow in the fuel rod bundle. The main emphasis of current research has been given to the analysis of the phase distribution around and downstream the spacer grid, the effect of the spacer grid structure, including the mixing vanes, the springs and the dimples on the void fraction distribution is investigated. The findings can contribute to a better understanding of three dimensional flow boiling characteristics and can be used to assist in optimizing the spacer grid.
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Messas E, IJsselmuiden A, Goudot G, Vlieger S, Zarka S, Puymirat E, Cholley B, Spaulding C, Hagège AA, Marijon E, Tanter M, Bertrand B, Rémond MC, Penot R, Ren B, den Heijer P, Pernot M, Spaargaren R. Feasibility and Performance of Noninvasive Ultrasound Therapy in Patients With Severe Symptomatic Aortic Valve Stenosis: A First-in-Human Study. Circulation 2021; 143:968-970. [PMID: 33486971 DOI: 10.1161/circulationaha.120.050672] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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El Faquir N, Vollema ME, Delgado V, Ren B, Spitzer E, Rasheed M, Rahhab Z, Geleijnse ML, Budde RPJ, de Jaegere PP, Bax JJ, Van Mieghem NM. Reclassification of aortic stenosis by fusion of echocardiography and computed tomography in low-gradient aortic stenosis. Neth Heart J 2020; 30:212-226. [PMID: 33052577 PMCID: PMC8941065 DOI: 10.1007/s12471-020-01501-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2020] [Indexed: 01/05/2023] Open
Abstract
Background The integration of computed tomography (CT)-derived left ventricular outflow tract area into the echocardiography-derived continuity equation results in the reclassification of a significant proportion of patients with severe aortic stenosis (AS) into moderate AS based on aortic valve area indexed to body surface area determined by fusion imaging (fusion AVAi). The aim of this study was to evaluate AS severity by a fusion imaging technique in patients with low-gradient AS and to compare the clinical impact of reclassified moderate AS versus severe AS. Methods We included 359 consecutive patients who underwent transcatheter aortic valve implantation for low-gradient, severe AS at two academic institutions and created a joint database. The primary endpoint was a composite of all-cause mortality and rehospitalisations for heart failure at 1 year. Results Overall, 35% of the population (n = 126) were reclassified to moderate AS [median fusion AVAi 0.70 (interquartile range, IQR 0.65–0.80) cm2/m2] and severe AS was retained as the classification in 65% [median fusion AVAi 0.49 (IQR 0.43–0.54) cm2/m2]. Lower body mass index, higher logistic EuroSCORE and larger aortic dimensions characterised patients reclassified to moderate AS. Overall, 57% of patients had a left ventricular ejection fraction (LVEF) <50%. Clinical outcome was similar in patients with reclassified moderate or severe AS. Among patients reclassified to moderate AS, non-cardiac mortality was higher in those with LVEF <50% than in those with LVEF ≥50% (log-rank p = 0.029). Conclusions The integration of CT and transthoracic echocardiography to obtain fusion AVAi led to the reclassification of one third of patients with low-gradient AS to moderate AS. Reclassification did not affect clinical outcome, although patients reclassified to moderate AS with a LVEF <50% had worse outcomes owing to excess non-cardiac mortality.
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Li Q, Ren B, Gui Q, Zhao J, Wu M, Shen M, Li D, Li D, Chen K, Tao M, Liang R. Blocking MAPK/ERK pathway sensitizes hepatocellular carcinoma cells to temozolomide via downregulating MGMT expression. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1305. [PMID: 33209885 PMCID: PMC7661899 DOI: 10.21037/atm-20-5478] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Background Hepatocellular carcinoma (HCC) is the fourth most common malignant tumor in China. Temozolomide (TMZ) is a common chemotherapy drug which can effectively kill HCC cells in vitro. However, it is possible that HCC cells possess intrinsic resistance to TMZ. A key mechanism of TMZ resistance is the overexpression of O6-methylguanine-DNA methyltransferase (MGMT). Studies have shown that MAPK may be related to MGMT expression, U0126 is a highly selective inhibitor of MEK1 and MEK2, which were crucial molecule in cascade of mitogen-activated protein kinase/extracellular signal regulated kinase (MAPK/ERK) pathway. Sorafenib was another widely applicated target drug in HCC which could inhibit multiple kinases including MAPK/ERK. This research was aimed to investigate the efficacy of MAPK/ERK inhibitor U0126 and sorafenib combine with TMZ in the treatment of HCC. Methods In HCC cells, MAPK/ERK signaling pathway was blocked by U0126 and sorafenib. The effect of blocking MAPK/ERK signaling pathway on TMZ-induced cytotoxicity was evaluated by MTT assay, flow cytometry and TUNEL assay. DNA damage protein and the expression of MGMT were detected by Western-blot. After the downregulation of MAPK/ERK signaling pathway, MGMT mRNA expression and the protein expression of MGMT were quantified by quantitative real-time polymerase chain reaction (RT-qPCR) and immunofluorescence assay, respectively. HepG2 cells were transfected with an MGMT over expression plasmid. After transfection, the effect of U0126 on TMZ-induced cytotoxicity was evaluated by MTT and Western-Blot in MGMT OE cells. The influence of Sorafenib on TMZ-induced cytotoxicity to HCC cells was also detected by MTT assay. Results U0126 can enhance the chemosensitivity of HCC cells to TMZ. At the same time, we also found that U0126 increases the damage to DNA caused by TMZ in HepG2 cells. Moreover, the results from RT-qPCR and Western blot showed that U0126 downregulated MGMT mRNA and MGMT protein expression via blocking MAPK/ERK pathway. Furthermore, after transfection with an MGMT expression plasmid, overexpression of MGMT restored U0126-induced chemosensitivity to TMZ in HCC cells. Sorafenib can also increase the chemosensitivity of HCC cells to TMZ. Conclusions Our studies suggest great clinical potential for the utilization of combined U0126 and TMZ in patients with advanced HCC.
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Zhao J, Li Q, Muktiali M, Ren B, Hu Y, Li D, Li Z, Li D, Xie Y, Tao M, Liang R. Effect of microwave ablation treatment of hepatic malignancies on serum cytokine levels. BMC Cancer 2020; 20:812. [PMID: 32847533 PMCID: PMC7448515 DOI: 10.1186/s12885-020-07326-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 08/20/2020] [Indexed: 12/18/2022] Open
Abstract
Background Microwave ablation (MWA) is widely used to treat unresectable primary and secondary malignancies of the liver, and a limited number of studies indicate that ablation can cause not only necrosis at the in situ site but also an immunoreaction of the whole body. This study aimed to investigate the effects of MWA on cytokines in patients who underwent MWA for a hepatic malignancy. Methods Patients admitted to the Oncology Department in the First Affiliated Hospital of Soochow University between June 2015 and February 2019 were selected. Peripheral blood was collected from patients with a hepatic malignancy treated with MWA. The levels of cytokines (IL-2, IFN-γ, TNF-α, IL-12 p40, IL-12 p70, IL-4, IL-6, IL-8, IL-10, and vascular endothelial growth factor (VEGF)) were detected with a Milliplex® MAP Kit. The comparison times were as follows: before ablation, 24 h after ablation, 15 days after ablation, and 30 days after ablation. Data were analyzed using a paired sample t-tests and Spearman’s correlation analysis. Results A total of 43 patients with hepatic malignancies were assessed. There were significant differences in IL-2, IL-12 p40, IL-12 p70, IL-1β, IL-8, and TNF-α at 24 h after MWA. Significant increases (> 2-fold vs. before ablation) were observed in IL-2, IL-1β, IL-6, IL-8, IL-10, and TNF-α after MWA. Elevated IL-2 and IL-6 levels after ablation were positively correlated with energy output during the MWA procedure. Conclusions WA treatment for hepatic malignancies can alter the serum levels of several cytokines such as IL-2 and IL-6.
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Liang J, Liu F, Zou J, Xu HHK, Han Q, Wang Z, Li B, Yang B, Ren B, Li M, Peng X, Li J, Zhang S, Zhou X, Cheng L. pH-Responsive Antibacterial Resin Adhesives for Secondary Caries Inhibition. J Dent Res 2020; 99:1368-1376. [PMID: 32600095 DOI: 10.1177/0022034520936639] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Secondary caries caused by dental plaque is one of the major reasons for the high failure rate of resin composite restoration. Although antimicrobial agent-modified dental restoration systems have been researched for years, few reported intelligent anticaries materials could respond to the change of the oral environment and help keep oral eubiosis. Herein, we report tertiary amine (TA)-modified resin adhesives (TA@RAs) with pH-responsive antibacterial effect to reduce the occurrence of secondary caries. Two kinds of newly designed TA monomers were synthesized: DMAEM (dodecylmethylaminoethyl methacrylate) and HMAEM (hexadecylmethylaminoethyl methacrylate). In the minimum inhibitory concentration and minimum bactericidal concentration test against Streptococcus mutans, Streptococcus sanguinis, and Streptococcus gordonii, they exhibited antibacterial effect only in acidic medium, which preliminarily verified the acid-activated effect of TAs. Then DMAEM and HMAEM were incorporated into adhesive resin at the mass fraction of 5%, yielding TA@RAs. In vivo and in vitro tests showed that the mechanical properties and biocompatibility of the adhesive were not affected. A S. mutans biofilm model in acidic and neutral medium was used and confirmed that TA@RAs could respond to the critical pH value of de-/remineralization and acquire reversible antibiofilm effect via the protonation and deprotonation of TAs. Meanwhile, the stability of antibacterial effect was confirmed via a 5-d pH-cycling experiment and a saliva-derived biofilm aging model. Furthermore, 16S rRNA gene sequencing showed that TA@RAs could increase the diversity of the saliva-derived biofilms, which implied that the novel materials could help regulate the microbial community to a healthy one. Finally, an in vitro demineralization model and in vivo secondary caries model were applied and demonstrated that TA@RAs could prevent secondary dental caries effectively. In summary, the reversible pH-responsive and non-drug release antibacterial resin adhesives ingeniously overcome the defect of the present materials and hold great promise for clinical application.
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