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Polymyxin combined with Ocimum gratissimum essential oil: one alternative strategy for combating polymyxin-resistant Klebsiella pneumoniae 多粘菌素与欧加木精油的结合:对抗耐多粘菌素肺炎克雷伯菌的一种替代策略
IF 3 4区 医学 Q3 MICROBIOLOGY Pub Date : 2024-09-18 DOI: 10.1099/jmm.0.001891
Andressa Leite Ferraz de Melo, Luana Rossato, Jannaína Velasques, Virginia Lopes de Sousa, Gabriel Victor Pina Rodrigues, Cláudia Andrea Lima Cardoso, Julia Pimentel Arantes, Bruno Fernandes Lima and Simone Simionatto
Introduction. Multidrug-resistant infections present a critical public health due to scarce treatment options and high mortality. Ocimum gratissimum L. essential oil (O.geo) is a natural resource rich in eugenol known for its antimicrobial activity.Hypothesis/Gap Statement. O.geo may exert effective antimicrobial activity against polymyxin-resistant Klebsiella pneumoniae and, when combined with Polymyxin B (PMB), may exhibit a synergistic effect, enhancing treatment efficacy and reducing antimicrobial resistance.Aim. This study aims to investigate the antimicrobial activity of O.geo against polymyxin-resistant K. pneumoniae using in vitro tests and an in vivo Caenorhabditis elegans model.Methodology. The O.geo was obtained by hydrodistillation followed by gas chromatography. The MIC and antibiofilm activity were determined using broth microdilution. Checkerboard and time-kill assays evaluated the combination of O.geo and polymyxin B (PMB), whereas a protein leakage assay verified its action.Results. Eugenol (39.67%) was a major constituent identified. The MIC of the O.geo alone ranged from 128 to 512 µg ml−1. The fractional inhibitory concentration index (0.28) and time-kill assay showed a synergism. In addition, O.geo and PMB inhibited biofilm formation and increased protein leakage in the plasma membrane. The treatment was tested in vivo using a Caenorhabditis elegans model, and significantly increased survival without toxicity was observed.Conclusion. O.geo could be used as a potential therapeutic alternative to combat infections caused by multidrug-resistant bacteria, especially in combination with PMB.
导言。耐多药感染是一个严重的公共卫生问题,因为治疗方法少、死亡率高。Ocimum gratissimum L.精油(O.geo)是一种富含丁香酚的天然资源,以其抗菌活性而闻名。O.geo可能对耐多粘菌素的肺炎克雷伯菌具有有效的抗菌活性,当与多粘菌素B(PMB)联合使用时,可能会产生协同效应,提高疗效并降低抗菌药耐药性。本研究旨在通过体外试验和体内秀丽隐杆线虫模型,研究 O.geo 对耐多粘菌素肺炎双球菌的抗菌活性。通过水蒸馏和气相色谱法获得 O.geo。使用肉汤微量稀释法测定 MIC 和抗生物膜活性。棋盘试验和时间致死试验评估了 O.geo 和多粘菌素 B (PMB) 的组合,而蛋白质渗漏试验则验证了其作用。经鉴定,丁香酚(39.67%)是主要成分。部分抑制浓度指数(0.28)和时间杀伤试验表明,O.geo 具有协同作用。此外,O.geo 和 PMB 还能抑制生物膜的形成并增加质膜蛋白质的渗漏。利用秀丽隐杆线虫模型对该疗法进行了体内试验,观察到其存活率显著提高,且无毒性。结论:O.geo 可作为一种潜在的替代疗法,用于抗击耐多药细菌引起的感染,尤其是与 PMB 结合使用时。
{"title":"Polymyxin combined with Ocimum gratissimum essential oil: one alternative strategy for combating polymyxin-resistant Klebsiella pneumoniae","authors":"Andressa Leite Ferraz de Melo, Luana Rossato, Jannaína Velasques, Virginia Lopes de Sousa, Gabriel Victor Pina Rodrigues, Cláudia Andrea Lima Cardoso, Julia Pimentel Arantes, Bruno Fernandes Lima and Simone Simionatto","doi":"10.1099/jmm.0.001891","DOIUrl":"https://doi.org/10.1099/jmm.0.001891","url":null,"abstract":"<span>Introduction.</span> Multidrug-resistant infections present a critical public health due to scarce treatment options and high mortality. <span>Ocimum gratissimum</span> L. essential oil (O.geo) is a natural resource rich in eugenol known for its antimicrobial activity.\u0000<span>Hypothesis/Gap Statement.</span> O.geo may exert effective antimicrobial activity against polymyxin-resistant Klebsiella pneumoniae and, when combined with Polymyxin B (PMB), may exhibit a synergistic effect, enhancing treatment efficacy and reducing antimicrobial resistance.\u0000<span>Aim.</span> This study aims to investigate the antimicrobial activity of O.geo against polymyxin-resistant <span>K. pneumoniae</span> using <span>in vitro</span> tests and an <span>in vivo Caenorhabditis elegans</span> model.\u0000<span>Methodology.</span> The O.geo was obtained by hydrodistillation followed by gas chromatography. The MIC and antibiofilm activity were determined using broth microdilution. Checkerboard and time-kill assays evaluated the combination of O.geo and polymyxin B (PMB), whereas a protein leakage assay verified its action.\u0000<span>Results.</span> Eugenol (39.67%) was a major constituent identified. The MIC of the O.geo alone ranged from 128 to 512 &#181;g ml<span>&#8722;1</span>. The fractional inhibitory concentration index (0.28) and time-kill assay showed a synergism. In addition, O.geo and PMB inhibited biofilm formation and increased protein leakage in the plasma membrane. The treatment was tested <span>in vivo</span> using a <span>Caenorhabditis elegans</span> model, and significantly increased survival without toxicity was observed.\u0000<span>Conclusion.</span> O.geo could be used as a potential therapeutic alternative to combat infections caused by multidrug-resistant bacteria, especially in combination with PMB.","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The impact of agar depth on antimicrobial susceptibility testing by disc diffusion 琼脂深度对碟片扩散法抗菌药敏感性测试的影响
IF 3 4区 医学 Q3 MICROBIOLOGY Pub Date : 2024-09-18 DOI: 10.1099/jmm.0.001890
Ioana D. Olaru, Sarah Schoeler and Frieder Schaumburg
Introduction. The European Committee on Antimicrobial Susceptibility Testing (EUCAST) specifies the agar depth (4±0.5 mm) when performing antimicrobial susceptibility testing (AST). Since the infrastructure to produce standardized agar may be lacking in settings with limited resources, we wanted to examine to what extent variation in agar depth affects the inhibition zone diameters of quality control (QC) strains and AST of clinical isolates.Methods. The inhibition zone diameters on Mueller–Hinton II agar with different depths (2–6 mm) were tested for various QC strain–antimicrobial agent combinations using Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213. The relationship between zone diameters at different agar depths and MICs was investigated for 35 clinical isolates (E. coli, Klebsiella pneumoniae, S. aureus and P. aeruginosa) from Sierra Leone using MICs as the reference.Results. The inhibition zone diameters were within the acceptance ranges as defined by the EUCAST for the majority of QC strains and antimicrobials, independent of the agar depth. At extreme agar depths, inhibition zones were more frequently out of range. The accuracy of AST varied for clinical isolates at different agar depths for categorical agreement (85.8–94.6%), major error rate (0.4–2.1%) and very major error rate (VME: 3.3–12.5%).Conclusions. Even if the QC strains were in the acceptance range at different agar depths, this does not rule out unacceptably high VME rates (>3%) in clinical isolates.
简介。欧洲抗菌药物敏感性检测委员会(EUCAST)规定了进行抗菌药物敏感性检测(AST)时的琼脂深度(4±0.5 毫米)。由于在资源有限的环境中可能缺乏生产标准化琼脂的基础设施,因此我们希望研究琼脂深度的变化在多大程度上会影响质控(QC)菌株的抑菌区直径和临床分离菌株的 AST。使用大肠埃希菌 ATCC 25922、铜绿假单胞菌 ATCC 27853 和金黄色葡萄球菌 ATCC 29213 在不同深度(2–6 mm)的 Mueller–Hinton II 琼脂上测试各种质控菌株–抗菌剂组合的抑菌区直径。以 MICs 为参照,对来自塞拉利昂的 35 个临床分离物(大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和铜绿假单胞菌)的不同琼脂深度的抑菌区直径与 MICs 之间的关系进行了研究。大多数质控菌株和抗菌剂的抑菌区直径都在欧盟食品添加剂和污染物分析委员会(EUCAST)规定的接受范围内,与琼脂深度无关。在琼脂深度极深的情况下,抑菌区更经常超出范围。对于不同琼脂深度的临床分离菌株,AST 的准确性在分类一致率(85.8%;94.6%)、重大错误率(0.4%;2.1%)和极重大错误率(VME:3.3%;12.5%)方面各不相同。即使质控菌株在不同的琼脂深度下都在可接受范围内,也不能排除临床分离物中存在不可接受的高 VME 率(>3%)。
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引用次数: 0
Antimicrobial spectrum against wound pathogens and cytotoxicity of star-arranged poly-l-lysine-based antimicrobial peptide polymers 星形排列聚赖氨酸基抗菌肽聚合物对伤口病原体的抗菌谱和细胞毒性
IF 3 4区 医学 Q3 MICROBIOLOGY Pub Date : 2024-09-13 DOI: 10.1099/jmm.0.001886
Aaron Doherty, Robert Murphy, Andreas Heise, Fidelma Fitzpatrick and Deirdre Fitzgerald-Hughes
Introduction. As growing numbers of patients are at higher risk of infection, novel topical broad-spectrum antimicrobials are urgently required for wound infection management. Robust pre-clinical studies should support the development of such novel antimicrobials.Gap statement. To date, evidence of robust investigation of the cytotoxicity and antimicrobial spectrum of activity of antimicrobial peptides (AMP)s is lacking in published literature. Using a more clinical lens, we address this gap in experimental approach, building on our experience with poly-l-lysine (PLL)-based AMP polymers.Aim. To evaluate the in vitro bactericidal activity and cytotoxicity of a PLL-based 16-armed star AMP polymer, designated 16-PLL10, as a novel candidate antimicrobial.Methods. Antimicrobial susceptibilities of clinical isolates and reference strains of ESKAPE (Enterococcus spp., Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp.) pathogens, to 16-PLL10 were investigated. Human erythrocyte haemolysis and keratinocyte viability assays were used to assess toxicity. Modifications were made to 16-PLL10 and re-evaluated for improvement.Results. Minimum bactericidal concentration of 16-PLL10 ranged from 1.25 µM to ≥25 µM. At 2.5 µM, 16-PLL10 was broadly bactericidal against ESKAPE strains/wound isolates. Log-reduction in colony forming units (c.f.u.) per millilitre after 1 h, ranged from 0.3 (E. cloacae) to 5.6 (K. pneumoniae). At bactericidal concentrations, 16-PLL10 was toxic to human keratinocyte and erythrocytes. Conjugates of 16-PLL10, Trifluoroacetylated (TFA)−16-PLL10, and Poly-ethylene glycol (PEG)ylated 16-PLL10, synthesised to address toxicity, only moderately reduced cytotoxicity and haemolysis.Conclusions. Due to poor selectivity indices, further development of 16-PLL10 is unlikely warranted. However, considering the unmet need for novel topical antimicrobials, the ease of AMP polymer synthesises/modification is attractive. To support more rational development, prioritising clinically relevant pathogens and human cells, to establish selective toxicity profiles in vitro, is critical. Further characterisation and discovery utilising artificial intelligence and computational screening approaches can accelerate future AMP nanomaterial development.
简介。由于越来越多的患者面临较高的感染风险,因此急需新型外用广谱抗菌药物来治疗伤口感染。强有力的临床前研究应支持此类新型抗菌药的开发。迄今为止,已发表的文献中缺乏对抗菌肽(AMP)的细胞毒性和抗菌谱活性进行深入研究的证据。基于我们在聚赖氨酸(PLL)基 AMP 聚合物方面的经验,我们将从更临床的角度来解决实验方法上的这一空白。评估基于 PLL 的 16 臂星形 AMP 聚合物(命名为 16-PLL10)作为新型候选抗菌剂的体外杀菌活性和细胞毒性。研究了临床分离菌株和 ESKAPE(肠球菌属、金黄色葡萄球菌、肺炎克雷伯菌、鲍曼不动杆菌、铜绿假单胞菌、肠杆菌属)病原体参考菌株对 16-PLL10 的抗菌敏感性。人类红细胞溶血和角质细胞活力测定用于评估毒性。对 16-PLL10 进行了改良,并重新评估了改良效果。16-PLL10 的最小杀菌浓度范围为 1.25 µM 至 ≥25 µM 。当浓度为 2.5 µM 时,16-PLL10 对 ESKAPE 菌株/伤口分离物具有广泛的杀菌作用。1 h 后,每毫升菌落形成单位(c.f.u.)的对数减少从 0.3(E. cloacae)到 5.6(K. pneumoniae)不等。在杀菌浓度下,16-PLL10 对人类角质细胞和红细胞具有毒性。为解决毒性问题而合成的 16-PLL10、三氟乙酰化(TFA)−16-PLL10 和聚乙二醇(PEG)酰化 16-PLL10 的共轭物只能适度降低细胞毒性和溶血作用。由于选择性指数较低,16-PLL10 不太可能得到进一步开发。不过,考虑到新型外用抗菌剂的需求尚未得到满足,AMP 聚合物易于合成/改性的特点还是很有吸引力的。为了支持更合理的开发,必须优先选择与临床相关的病原体和人类细胞,在体外建立选择性毒性特征。利用人工智能和计算筛选方法进一步表征和发现AMP纳米材料,可以加速未来的AMP纳米材料开发。
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引用次数: 0
Gut microbiota plays a significant role in gout 肠道微生物群在痛风中发挥着重要作用
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-17 DOI: 10.1099/jmm.0.001824
Zhi-Peng Feng, Xiao-Yan Wang, Hong-Yi Xin, Shao-Li Huang, Hong-Yu Huang, Qiang Xin, Xi-He Zhang and Hong-Wu Xin
With the development of social economy, the incidence of gout is increasing, which is closely related to people’s increasingly rich diet. Eating a diet high in purine, fat, sugar and low-fibre for a long time further aggravates gout by affecting uric acid metabolism. The renal metabolism mechanism of uric acid has been thoroughly studied. To find a new treatment method for gout, increasing studies have recently been conducted on the mechanism of intestinal excretion, metabolism and absorption of uric acid. The most important research is the relationship between intestinal microbiota and the risk of gout. Gut microbiota represent bacteria that reside in a host’s gastrointestinal tract. The composition of the gut microbiota is associated with protection against pathogen colonization and disease occurrence. This review focuses on how gut microbiota affects gout through uric acid and discusses the types of bacteria that may be involved in the occurrence and progression of gout. We also describe potential therapy for gout by restoring gut microbiota homeostasis and reducing uric acid levels. We hold the perspective that changing intestinal microbiota may become a vital method for effectively preventing or treating gout.
随着社会经济的发展,痛风的发病率越来越高,这与人们日益丰富的饮食结构密切相关。长期食用高嘌呤、高脂肪、高糖、低纤维的饮食会影响尿酸代谢,从而进一步加重痛风。尿酸的肾脏代谢机制已被深入研究。为了找到治疗痛风的新方法,近来对尿酸的肠道排泄、代谢和吸收机制的研究越来越多。最重要的研究是肠道微生物群与痛风风险之间的关系。肠道微生物群代表居住在宿主胃肠道中的细菌。肠道微生物群的组成与防止病原体定植和疾病发生有关。本综述重点探讨肠道微生物群如何通过尿酸影响痛风,并讨论可能参与痛风发生和发展的细菌类型。我们还介绍了通过恢复肠道微生物群平衡和降低尿酸水平来治疗痛风的潜在方法。我们认为,改变肠道微生物群可能成为有效预防或治疗痛风的重要方法。
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引用次数: 0
Klebsiella pneumoniae sequence type 147: a high-risk clone increasingly associated with plasmids carrying both resistance and virulence elements 肺炎克雷伯菌序列 147 型:与携带抗性和毒力元件的质粒日益相关的高风险克隆
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-17 DOI: 10.1099/jmm.0.001823
Jane F. Turton, Claire Perry, Kim McGowan, Jack A. Turton and Russell Hope
Introduction. The first hybrid resistance/virulence plasmid, combining elements from virulence plasmids described in hypervirulent types of Klebsiella pneumoniae with those from conjugative resistance plasmids, was described in an isolate of sequence type (ST) 147 from 2016. Subsequently, this type has been increasingly associated with these plasmids.Hypothesis or gap statement. The extent of carriage of hybrid virulence/resistance plasmids in nosocomial isolates of K. pneumoniae requires further investigation.Aim. To describe the occurrence of virulence/resistance plasmids among isolates of K. pneumoniae received by the UK reference laboratory, particularly among representatives of ST147, and to compare their sequences.Methodology. Isolates received by the laboratory during 2022 and the first half of 2023 (n=1278) were screened for virulence plasmids by PCR detection of rmpA/rmpA2 and typed by variable-number tandem repeat analysis. Twenty-nine representatives of ST147 (including a single-locus variant) from seven hospital laboratories were subjected to long-read nanopore sequencing using high-accuracy q20 chemistry to provide complete assemblies.Results.rmpA/rmpA2 were detected in 110 isolates, of which 59 belonged to hypervirulent K1-ST23, K2-ST86 and K2-ST65/375. Of the remainder, representatives of ST147 formed the largest group, with 22 rmpA/rmpA2-positive representatives (out of 47 isolates). Representatives were from 19 hospital laboratories, with rmpA/rmpA2-positive isolates from 10. Nanopore sequencing of 29 representatives of ST147 divided them into those with no virulence plasmid (n=12), those with non-New Delhi metallo-β-lactamase (NDM) virulence plasmids (n=6) and those carrying blaNDM-5 (n=9) or blaNDM-1 (n=2) virulence plasmids. These plasmids were of IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) replicon types. Most of the non-NDM virulence plasmids were highly similar to the originally described KpvST147L_NDM plasmid. Those carrying blaNDM-5 were highly similar to one another and to previously described plasmids in ST383 and carried an extensive array of resistance genes. Comparison of the fully assembled chromosomes indicated multiple introductions of ST147 in UK hospitals.Conclusion. This study highlights the high proportion of representatives of ST147 that carry IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) hybrid resistance virulence plasmids. It is important to be aware of the high probability that representatives of this type carry these plasmids combining resistance and virulence determinants and of the consequent increased risk to patients.
导言。2016 年,在一个序列类型(ST)147 的分离株中首次描述了抗性/毒力混合质粒,该质粒结合了在肺炎克雷伯氏菌高毒力类型中描述的毒力质粒元素和共轭抗性质粒元素。随后,该类型越来越多地与这些质粒有关。肺炎克雷伯菌的鼻腔分离物中携带混合毒力/耐药性质粒的程度需要进一步调查。描述英国参考实验室收到的肺炎克雷伯菌分离株中毒力/耐药性质粒的发生情况,尤其是 ST147 的代表株,并比较其序列。通过 PCR 检测 rmpA/rmpA2 筛选实验室在 2022 年和 2023 年上半年收到的分离株(n=1278)中的毒力质粒,并通过变数串联重复分析进行分型。对来自 7 家医院实验室的 29 个 ST147 代表株(包括一个单病灶变异株)使用高精度 q20 化学方法进行了长读程纳米孔测序,以提供完整的组合。在其余的分离物中,ST147 的代表构成了最大的群体,有 22 个 rmpA/rmpA2 阳性的代表(在 47 个分离物中)。这些代表来自 19 家医院实验室,其中 10 家实验室的分离物为 rmpA/rmpA2 阳性。对 29 个 ST147 代表株进行了纳米孔测序,将其分为无毒力质粒(12 个)、非新德里金属β-内酰胺酶(NDM)毒力质粒(6 个)和携带 blaNDM-5 (9 个)或 blaNDM-1 (2 个)毒力质粒的代表株。这些质粒属于 IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) 复制子类型。大多数非 NDM 毒力质粒与最初描述的 KpvST147L_NDM 质粒高度相似。携带 blaNDM-5 的质粒彼此高度相似,也与之前描述的 ST383 中的质粒高度相似,并携带大量抗性基因。比较完全组装的染色体表明,ST147 在英国医院中多次引入。本研究强调了 ST147 中携带 IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) 杂交抗性毒力质粒的高比例代表。我们必须意识到这种类型的细菌极有可能携带这些结合了抗药性和毒力决定因子的质粒,从而增加了患者的风险。
{"title":"Klebsiella pneumoniae sequence type 147: a high-risk clone increasingly associated with plasmids carrying both resistance and virulence elements","authors":"Jane F. Turton, Claire Perry, Kim McGowan, Jack A. Turton and Russell Hope","doi":"10.1099/jmm.0.001823","DOIUrl":"https://doi.org/10.1099/jmm.0.001823","url":null,"abstract":"<span>Introduction.</span> The first hybrid resistance/virulence plasmid, combining elements from virulence plasmids described in hypervirulent types of <span>Klebsiella pneumoniae</span> with those from conjugative resistance plasmids, was described in an isolate of sequence type (ST) 147 from 2016. Subsequently, this type has been increasingly associated with these plasmids.\u0000<span>Hypothesis or gap statement.</span> The extent of carriage of hybrid virulence/resistance plasmids in nosocomial isolates of <span>K. pneumoniae</span> requires further investigation.\u0000<span>Aim.</span> To describe the occurrence of virulence/resistance plasmids among isolates of <span>K. pneumoniae</span> received by the UK reference laboratory, particularly among representatives of ST147, and to compare their sequences.\u0000<span>Methodology.</span> Isolates received by the laboratory during 2022 and the first half of 2023 (<span>n</span>=1278) were screened for virulence plasmids by PCR detection of <span>rmpA</span>/<span>rmpA2</span> and typed by variable-number tandem repeat analysis. Twenty-nine representatives of ST147 (including a single-locus variant) from seven hospital laboratories were subjected to long-read nanopore sequencing using high-accuracy q20 chemistry to provide complete assemblies.\u0000<span>Results.</span>\u0000<span>rmpA</span>/<span>rmpA2</span> were detected in 110 isolates, of which 59 belonged to hypervirulent K1-ST23, K2-ST86 and K2-ST65/375. Of the remainder, representatives of ST147 formed the largest group, with 22 <span>rmpA</span>/<span>rmpA2</span>-positive representatives (out of 47 isolates). Representatives were from 19 hospital laboratories, with <span>rmpA</span>/<span>rmpA2</span>-positive isolates from 10. Nanopore sequencing of 29 representatives of ST147 divided them into those with no virulence plasmid (<span>n</span>=12), those with non-New Delhi metallo-&#946;-lactamase (NDM) virulence plasmids (<span>n</span>=6) and those carrying <span>bla</span>\u0000<span>NDM-5</span> (<span>n</span>=9) or <span>bla</span>\u0000<span>NDM-1</span> (<span>n</span>=2) virulence plasmids. These plasmids were of IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) replicon types. Most of the non-NDM virulence plasmids were highly similar to the originally described KpvST147L_NDM plasmid. Those carrying <span>bla</span>\u0000<span>NDM-5</span> were highly similar to one another and to previously described plasmids in ST383 and carried an extensive array of resistance genes. Comparison of the fully assembled chromosomes indicated multiple introductions of ST147 in UK hospitals.\u0000<span>Conclusion.</span> This study highlights the high proportion of representatives of ST147 that carry IncFIB(pNDM-Mar)/IncHI1B(pNDM-MAR) hybrid resistance virulence plasmids. It is important to be aware of the high probability that representatives of this type carry these plasmids combining resistance and virulence determinants and of the consequent increased risk to patients.","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140615723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Evaluation of a new CT/NG/TV/MG Real-Time PCR Kit (Vircell) versus the Allplex STI Essential Assay (Seegene) for the diagnosis of sexually transmitted infections 新型 CT/NG/TV/MG 实时 PCR 检测试剂盒(Vircell)与 Allplex STI Essential Assay(Seegene)在性传播感染诊断方面的对比评估
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-09 DOI: 10.1099/jmm.0.001797
María Aguilera-Franco, María Tarriño-León, MJ Olivares-Durán, Beatriz Espadafor, Javier Rodríguez-Granger, Juan Antonio Reguera, Fernando Cobo, Antonio Sampedro and José María Navarro
Sexually transmitted infections (STI) are a public health problem. Real-time PCR assays are the most sensitive test for screening and diagnosis of these infections. The aim of this study was to evaluate a new CT/NG/TV/MG Real-Time PCR (RT-PCR) kit (Vircell) for the detection of Chamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis for the diagnosis of sexual transmitted infections using the Allplex STI Essential Assay (Seegene) as the reference’s method. A total of 497 samples from different anatomical sites (endocervical, urethral, rectal, pharyngeal and urine) were analysed from October 2022 to February 2023. A total of 108 (21.73 %) and 106 (21.33 %) positive samples were found for any of the assays used. The most commonly detected pathogen was N. gonorrhoeae (52 samples; 10.46 %), and the least commonly detected was T. vaginalis (three samples; 0.60 %). The anatomical site with the highest prevalence of micro-organisms was a non-urogenital site, the pharynx (26 positive samples; 5.23 %). Using the Allplex STI Essential Assay (Seegene) as the reference method, the diagnosis performance showed that the average specificity of CT/NG/TV/MG RT-PCR Kit (Vircell) was 99.84 % and the sensitivity was 99.53 %. The overall concordance was k=0.98 (CI95 %; 0.96–1). In conclusion, the CT/NG/TV/MG RT-PCR Kit (Vircell) assay shows a good sensitivity and specificity and constitutes a promising and additional alternative to routine procedures for distinct types of clinical specimen in diagnosis STI.
性传播感染(STI)是一个公共卫生问题。实时 PCR 检测是筛查和诊断这些感染的最灵敏检测方法。本研究旨在评估一种新型 CT/NG/TV/MG 实时 PCR (RT-PCR) 检测试剂盒(Vircell),该试剂盒用于检测沙眼衣原体、淋病奈瑟菌、生殖器支原体和阴道毛滴虫,并以 Allplex STI Essential Assay(Seegene)作为参考方法,用于诊断性传播感染。从 2022 年 10 月到 2023 年 2 月,共分析了 497  份来自不同解剖部位(宫颈内口、尿道、直肠、咽部和尿液)的样本。在使用的任何一种检测方法中,共发现 108 份(21.73 %)和 106 份(21.33 %)阳性样本。最常检测到的病原体是淋球菌(52 个样本;10.46 %),最少检测到的病原体是阴道球菌(3 个样本;0.60 %)。微生物感染率最高的解剖部位是非泌尿生殖器部位,即咽部(26 个阳性样本;5.23 %)。以 Allplex STI Essential Assay(Seegene)为参照方法,诊断结果显示 CT/NG/TV/MG RT-PCR Kit(Vircell)的平均特异性为 99.84%,灵敏度为 99.53%。总体一致性为 k=0.98 (CI95 %; 0.96–1)。总之,CT/NG/TV/MG RT-PCR 检测试剂盒(Vircell)显示出良好的灵敏度和特异性,是诊断 STI 不同类型临床标本的常规程序之外的另一种有前途的方法。
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引用次数: 0
Characterization of invasive Group B Streptococcus isolates from Western Australian infants, 2004–2020 2004-2020 年西澳大利亚州婴儿中侵入性 B 群链球菌分离物的特征
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-03 DOI: 10.1099/jmm.0.001822
Ginger Hilpipre, Lucy L. Furfaro, Michelle Porter, Christopher C. Blyth and Daniel K. Yeoh
Background. Invasive Group B Streptococcus (GBS; Streptococcus agalactiae) remains a leading cause of infant morbidity and mortality. Intrapartum antibiotic prophylaxis (IAP) has been implemented in many countries with a reduction in early-onset disease, but an effective vaccine may further reduce the disease burden. Candidate vaccines targeting capsular polysaccharides and surface proteins are now in clinical trials.Methods. Using whole-genome sequencing and phenotypic antimicrobial susceptibility testing, we characterized sterile-site GBS isolates recovered from Western Australian infants between 2004 and 2020. Characteristics were compared between three time periods: 2004–2008, 2009–2015 and 2016–2020.Results. A total of 135 isolates were identified. The proportion of serotype III (22.7 % in Period 1 to 47.9 % in Period 3, P=0.04) and clonal complex 17 (13.6–39.6 %, P=0.01) isolates increased over time. Overall coverage of vaccines currently being trialled was >95 %. No isolates were penicillin resistant (MIC>0.25 mg l–1), but 21.5 % of isolates had reduced penicillin susceptibility (MIC>0.12 mg l–1) and penicillin MIC increased significantly over time (P=0.04). Clindamycin resistance increased over time to 45.8 % in the latest period.Conclusions. Based on comprehensive characterization of invasive infant GBS in Western Australia, we found that coverage for leading capsular polysaccharide and surface protein vaccine candidates was high. The demonstrated changes in serotype and molecular type highlight the need for ongoing surveillance, particularly with regard to future GBS vaccination programmes. The reduced susceptibility to IAP agents over time should inform changes to antibiotic guidelines.
背景。侵袭性 B 群链球菌(GBS;无乳链球菌)仍然是婴儿发病和死亡的主要原因。许多国家已实施产前抗生素预防 (IAP),从而减少了早期发病率,但有效的疫苗可进一步减轻疾病负担。针对荚膜多糖和表面蛋白的候选疫苗目前正在临床试验中。利用全基因组测序和表型抗菌药敏感性测试,我们对 2004 年至 2020 年间从西澳大利亚婴儿中分离的无菌部位 GBS 进行了鉴定。我们比较了 2004–2008 年、2009–2015 年和 2016–2020 年三个时期的特征。结果:共发现 135 个分离株。随着时间的推移,血清型 III(第 1 期为 22.7%,第 3 期为 47.9%,P=0.04)和克隆复合体 17(13.6%,39.6%,P=0.01)分离株的比例有所增加。目前正在试用的疫苗的总体覆盖率为 95%。没有分离菌株对青霉素耐药(MIC>0.25 mg l–1),但有 21.5 % 的分离菌株对青霉素的敏感性降低(MIC>0.12 mg l–1),青霉素 MIC 随时间显著增加(P=0.04)。克林霉素耐药性随着时间的推移而增加,在最近一个时期达到45.8%。根据西澳大利亚州侵袭性婴儿 GBS 的综合特征,我们发现主要的荚膜多糖和表面蛋白候选疫苗的覆盖率很高。血清型和分子类型的明显变化凸显了持续监测的必要性,尤其是在未来的 GBS 疫苗接种计划中。随着时间的推移,对 IAP 制剂的敏感性降低,这为抗生素指南的改变提供了参考。
{"title":"Characterization of invasive Group B Streptococcus isolates from Western Australian infants, 2004–2020","authors":"Ginger Hilpipre, Lucy L. Furfaro, Michelle Porter, Christopher C. Blyth and Daniel K. Yeoh","doi":"10.1099/jmm.0.001822","DOIUrl":"https://doi.org/10.1099/jmm.0.001822","url":null,"abstract":"<span>Background.</span> Invasive Group B <span>Streptococcus</span> (GBS; <span>Streptococcus agalactiae</span>) remains a leading cause of infant morbidity and mortality. Intrapartum antibiotic prophylaxis (IAP) has been implemented in many countries with a reduction in early-onset disease, but an effective vaccine may further reduce the disease burden. Candidate vaccines targeting capsular polysaccharides and surface proteins are now in clinical trials.\u0000<span>Methods.</span> Using whole-genome sequencing and phenotypic antimicrobial susceptibility testing, we characterized sterile-site GBS isolates recovered from Western Australian infants between 2004 and 2020. Characteristics were compared between three time periods: 2004&#8211;2008, 2009&#8211;2015 and 2016&#8211;2020.\u0000<span>Results.</span> A total of 135 isolates were identified. The proportion of serotype III (22.7&#8202;% in Period 1 to 47.9&#8202;% in Period 3, <span>P</span>=0.04) and clonal complex 17 (13.6&#8211;39.6&#8202;%, <span>P</span>=0.01) isolates increased over time. Overall coverage of vaccines currently being trialled was &gt;95&#8202;%. No isolates were penicillin resistant (MIC&gt;0.25 mg l<span>&#8211;1</span>), but 21.5&#8202;% of isolates had reduced penicillin susceptibility (MIC&gt;0.12 mg l<span>&#8211;1</span>) and penicillin MIC increased significantly over time (<span>P</span>=0.04). Clindamycin resistance increased over time to 45.8&#8202;% in the latest period.\u0000<span>Conclusions.</span> Based on comprehensive characterization of invasive infant GBS in Western Australia, we found that coverage for leading capsular polysaccharide and surface protein vaccine candidates was high. The demonstrated changes in serotype and molecular type highlight the need for ongoing surveillance, particularly with regard to future GBS vaccination programmes. The reduced susceptibility to IAP agents over time should inform changes to antibiotic guidelines.","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140575159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
CXCR2 perturbation promotes Staphylococcus aureus implant-associated infection CXCR2 干扰会促进金黄色葡萄球菌植入相关感染
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-03 DOI: 10.1099/jmm.0.001821
Mike Akaraphanth, Tara M. Nordgren and Casey M. Gries
Introduction.Staphylococcus aureus is the leading cause of acute medical implant infections, representing a significant modern medical concern. The success of S. aureus as a pathogen in these cases resides in its arsenal of virulence factors, resistance to multiple antimicrobials, mechanisms of immune modulation, and ability to rapidly form biofilms associated with implant surfaces. S. aureus device-associated, biofilm-mediated infections are often persistent and notoriously difficult to treat, skewing innate immune responses to promote chronic reoccurring infections. While relatively little is known of the role neutrophils play in response to acute S. aureus biofilm infections, these effector cells must be efficiently recruited to sites of infection via directed chemotaxis. Here we investigate the effects of modulating CXC chemokine receptor 2 (CXCR2) activity, predominantly expressed on neutrophils, during S. aureus implant-associated infection.Hypothesis. We hypothesize that modulation of CXCR2 expression and/or signalling activities during S. aureus infection, and thus neutrophil recruitment, extravasation and antimicrobial activity, will affect infection control and bacterial burdens in a mouse model of implant-associated infection.Aim. This investigation aims to elucidate the impact of altered CXCR2 activity during S. aureus biofilm-mediated infection that may help develop a framework for an effective novel strategy to prevent morbidity and mortality associated with implant infections.Methodology. To examine the role of CXCR2 during S. aureus implant infection, we employed a mouse model of indwelling subcutaneous catheter infection using a community-associated methicillin-resistant S. aureus (MRSA) strain. To assess the role of CXCR2 induction or inhibition during infection, treatment groups received daily intraperitoneal doses of either Lipocalin-2 (Lcn2) or AZD5069, respectively. At the end of the study, catheters and surrounding soft tissues were analysed for bacterial burdens and dissemination, and Cxcr2 transcription within the implant-associated tissues was quantified.Results. Mice treated with Lcn2 developed higher bacterial burdens within the soft tissue surrounding the implant site, which was associated with increased Cxcr2 expression. AZD5069 treatment also resulted in increased implant- and tissues-associated bacterial titres, as well as enhanced Cxcr2 expression.Conclusion. Our results demonstrate that CXCR2 plays an essential role in regulating the severity of S. aureus implant-associated infections. Interestingly, however, perturbation of CXCR2 expression or signalling both resulted in enhanced Cxcr2 transcription and elevated implant-associated bacterial burdens. T
导言:金黄色葡萄球菌是急性医用植入物感染的主要病因,是现代医学的一个重大问题。在这些病例中,金黄色葡萄球菌作为病原体的成功之处在于它的毒力因子库、对多种抗菌药物的耐药性、免疫调节机制以及与植入物表面快速形成生物膜的能力。由生物膜介导的金黄色葡萄球菌器械相关感染通常具有顽固性和难以治疗的特点,会影响先天性免疫反应,导致慢性再发感染。虽然人们对中性粒细胞在应对急性金黄色葡萄球菌生物膜感染中所起的作用知之甚少,但这些效应细胞必须通过定向趋化作用被有效地招募到感染部位。在此,我们研究了在金黄色葡萄球菌植入相关感染期间调节主要表达于中性粒细胞的 CXC 趋化因子受体 2(CXCR2)活性的影响。我们假设,在金黄色葡萄球菌感染过程中调节 CXCR2 的表达和/或信号活动,进而调节中性粒细胞的募集、外渗和抗菌活性,将影响植入相关感染小鼠模型的感染控制和细菌负荷。本研究旨在阐明在金黄色葡萄球菌生物膜介导的感染过程中,CXCR2活性改变的影响,这可能有助于制定一个有效的新策略框架,预防与种植体感染相关的发病率和死亡率。为了研究 CXCR2 在金黄色葡萄球菌植入物感染过程中的作用,我们使用社区相关耐甲氧西林金黄色葡萄球菌(MRSA)菌株建立了留置皮下导管感染的小鼠模型。为了评估 CXCR2 在感染过程中的诱导或抑制作用,治疗组每天分别腹腔注射 Lipocalin-2 (Lcn2) 或 AZD5069。研究结束时,分析导管和周围软组织的细菌负荷和传播情况,并对植入物相关组织内的 Cxcr2 转录进行量化。结果发现,接受 Lcn2 治疗的小鼠植入部位周围软组织内的细菌量较高,这与 Cxcr2 表达量增加有关。AZD5069 治疗也导致植入物和组织相关细菌滴度增加,以及 Cxcr2 表达增强。我们的研究结果表明,CXCR2 在调节金黄色葡萄球菌种植体相关感染的严重程度中起着至关重要的作用。但有趣的是,干扰 CXCR2 的表达或信号传导都会导致 Cxcr2 转录增强和种植体相关细菌负担增加。因此,CXCR2 似乎经过精细调整,能有效招募效应细胞并介导控制金黄色葡萄球菌生物膜介导的感染。
{"title":"CXCR2 perturbation promotes Staphylococcus aureus implant-associated infection","authors":"Mike Akaraphanth, Tara M. Nordgren and Casey M. Gries","doi":"10.1099/jmm.0.001821","DOIUrl":"https://doi.org/10.1099/jmm.0.001821","url":null,"abstract":"<span>Introduction.</span>\u0000<span>Staphylococcus aureus</span> is the leading cause of acute medical implant infections, representing a significant modern medical concern. The success of <span>S. aureus</span> as a pathogen in these cases resides in its arsenal of virulence factors, resistance to multiple antimicrobials, mechanisms of immune modulation, and ability to rapidly form biofilms associated with implant surfaces. <span>S. aureus</span> device-associated, biofilm-mediated infections are often persistent and notoriously difficult to treat, skewing innate immune responses to promote chronic reoccurring infections. While relatively little is known of the role neutrophils play in response to acute <span>S. aureus</span> biofilm infections, these effector cells must be efficiently recruited to sites of infection via directed chemotaxis. Here we investigate the effects of modulating CXC chemokine receptor 2 (CXCR2) activity, predominantly expressed on neutrophils, during <span>S. aureus</span> implant-associated infection.\u0000<span>Hypothesis.</span> We hypothesize that modulation of CXCR2 expression and/or signalling activities during <span>S. aureus</span> infection, and thus neutrophil recruitment, extravasation and antimicrobial activity, will affect infection control and bacterial burdens in a mouse model of implant-associated infection.\u0000<span>Aim.</span> This investigation aims to elucidate the impact of altered CXCR2 activity during <span>S. aureus</span> biofilm-mediated infection that may help develop a framework for an effective novel strategy to prevent morbidity and mortality associated with implant infections.\u0000<span>Methodology.</span> To examine the role of CXCR2 during <span>S. aureus</span> implant infection, we employed a mouse model of indwelling subcutaneous catheter infection using a community-associated methicillin-resistant <span>S. aureus</span> (MRSA) strain. To assess the role of CXCR2 induction or inhibition during infection, treatment groups received daily intraperitoneal doses of either Lipocalin-2 (Lcn2) or AZD5069, respectively. At the end of the study, catheters and surrounding soft tissues were analysed for bacterial burdens and dissemination, and <span>Cxcr2</span> transcription within the implant-associated tissues was quantified.\u0000<span>Results.</span> Mice treated with Lcn2 developed higher bacterial burdens within the soft tissue surrounding the implant site, which was associated with increased <span>Cxcr2</span> expression. AZD5069 treatment also resulted in increased implant- and tissues-associated bacterial titres, as well as enhanced <span>Cxcr2</span> expression.\u0000<span>Conclusion.</span> Our results demonstrate that CXCR2 plays an essential role in regulating the severity of <span>S. aureus</span> implant-associated infections. Interestingly, however, perturbation of CXCR2 expression or signalling both resulted in enhanced <span>Cxcr2</span> transcription and elevated implant-associated bacterial burdens. T","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140575246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Rhein kills Actinobacillus pleuropneumoniae, reduces biofilm formation, and effectively treats bacterial lung infections in mice. Rhein 可杀死胸膜肺炎放线杆菌,减少生物膜的形成,有效治疗小鼠肺部细菌感染。
IF 3 4区 医学 Q2 Medicine Pub Date : 2024-04-01 DOI: 10.1099/jmm.0.001826
Haifeng Ding, Yilin Bai, Weiyu Luo, Hao Li, Chunling Zhu, Xueqin Zhao, Huarun Sun, Yuliang Wen, Wei Zhang, Shouping Zhang, Bo Wen, Ruibiao Wang, Longfei Zhang, Xuehan Liu, Jiyuan Shen, Jianhe Hu, Lei Wang, Yueyu Bai, Chengshui Liao, Yundi Wu, Xilong Wu, Ke Ding
Background. Actinobacillus pleuropneumoniae, a member of the Pasteurellaceae family, is known for its highly infectious nature and is the primary causative agent of infectious pleuropneumonia in pigs. This disease poses a considerable threat to the global pig industry and leads to substantial economic losses due to reduced productivity, increased mortality rates, and the need for extensive veterinary care and treatment. Due to the emergence of multi-drug-resistant strains, Chinese herbal medicine is considered one of the best alternatives to antibiotics due to its unique mechanism of action and other properties. As a type of Chinese herbal medicine, Rhein has the advantages of a wide antibacterial spectrum and is less likely to develop drug resistance, which can perfectly solve the limitations of current antibacterial treatments.Methods. The killing effect of Rhein on A. pleuropneumoniae was detected by fluorescence quantification of differential expression changes of key genes, and scanning electron microscopy was used to observe the changes in A. pleuropneumoniae status after Rhein treatment. Establishing a mouse model to observe the treatment of Rhein after A. pleuropneumoniae infection.Results. Here, in this study, we found that Rhein had a good killing effect on A. pleuropneumoniae and that the MIC was 25 µg ml-1. After 3 h of action, Rhein (4×MIC) completely kills A. pleuropneumoniae and Rhein has good stability. In addition, the treatment with Rhein (1×MIC) significantly reduced the formation of bacterial biofilms. Therapeutic evaluation in a murine model showed that Rhein protects mice from A. pleuropneumoniae and relieves lung inflammation. Quantitative RT-PCR (Quantitative reverse transcription polymerase chain reaction is a molecular biology technique that combines both reverse transcription and polymerase chain reaction methods to quantitatively detect the amount of a specific RNA molecule) results showed that Rhein treatment significantly downregulated the expression of the IL-18 (Interleukin refers to a class of cytokines produced by white blood cells), TNF-α, p65 and p38 genes. Along with the downregulation of genes such as IL-18, it means that Rhein has an inhibitory effect on the expression of these genes, thereby reducing the activation of inflammatory cells and the production of inflammatory mediators. This helps reduce inflammation and protects tissue from further damage.Conclusions. This study reports the activity of Rhein against A. pleuropneumoniae and its mechanism, and reveals the ability of Rhein to treat A. pleuropneumoniae infection in mice, laying the foundation for the development of new drugs for bacterial infections.
背景。胸膜肺炎放线杆菌属于巴斯德氏菌科,以其高度传染性而闻名,是猪传染性胸膜肺炎的主要致病菌。这种疾病对全球养猪业构成了相当大的威胁,由于生产率降低、死亡率上升以及需要大量兽医护理和治疗,导致了巨大的经济损失。由于多种抗药性菌株的出现,中草药因其独特的作用机制和其他特性,被认为是抗生素的最佳替代品之一。大黄作为一种中药材,具有抗菌谱广、不易产生耐药性等优点,完全可以解决目前抗菌治疗的局限性。通过荧光定量分析关键基因的差异表达变化,检测大黄对胸膜肺炎甲菌的杀灭作用,并用扫描电镜观察大黄治疗后胸膜肺炎甲菌状态的变化。结果。在本研究中,我们发现大黄对胸膜肺炎甲菌有很好的杀灭作用,其 MIC 为 25 µg ml-1。作用 3 小时后,大黄(4×MIC)可完全杀死胸膜肺炎甲菌,且大黄具有良好的稳定性。此外,使用 Rhein(1×MIC)治疗可显著减少细菌生物膜的形成。在小鼠模型中进行的治疗评估表明,Rhein 能保护小鼠免受胸膜肺炎甲菌感染,并缓解肺部炎症。定量 RT-PCR(定量反转录聚合酶链式反应,是一种分子生物学技术,结合了反转录和聚合酶链式反应两种方法,用于定量检测特定 RNA 分子的数量)结果显示,大黄霉素能显著下调 IL-18(白细胞介素,指白细胞产生的一类细胞因子)、TNF-α、p65 和 p38 基因的表达。随着 IL-18 等基因的下调,这意味着 Rhein 对这些基因的表达具有抑制作用,从而减少了炎症细胞的激活和炎症介质的产生。这有助于减轻炎症,保护组织免受进一步损伤。本研究报道了大黄霉素对胸膜肺炎甲虫的活性及其机制,揭示了大黄霉素治疗小鼠胸膜肺炎甲虫感染的能力,为开发治疗细菌感染的新药奠定了基础。
{"title":"Rhein kills Actinobacillus pleuropneumoniae, reduces biofilm formation, and effectively treats bacterial lung infections in mice.","authors":"Haifeng Ding, Yilin Bai, Weiyu Luo, Hao Li, Chunling Zhu, Xueqin Zhao, Huarun Sun, Yuliang Wen, Wei Zhang, Shouping Zhang, Bo Wen, Ruibiao Wang, Longfei Zhang, Xuehan Liu, Jiyuan Shen, Jianhe Hu, Lei Wang, Yueyu Bai, Chengshui Liao, Yundi Wu, Xilong Wu, Ke Ding","doi":"10.1099/jmm.0.001826","DOIUrl":"https://doi.org/10.1099/jmm.0.001826","url":null,"abstract":"Background. Actinobacillus pleuropneumoniae, a member of the Pasteurellaceae family, is known for its highly infectious nature and is the primary causative agent of infectious pleuropneumonia in pigs. This disease poses a considerable threat to the global pig industry and leads to substantial economic losses due to reduced productivity, increased mortality rates, and the need for extensive veterinary care and treatment. Due to the emergence of multi-drug-resistant strains, Chinese herbal medicine is considered one of the best alternatives to antibiotics due to its unique mechanism of action and other properties. As a type of Chinese herbal medicine, Rhein has the advantages of a wide antibacterial spectrum and is less likely to develop drug resistance, which can perfectly solve the limitations of current antibacterial treatments.Methods. The killing effect of Rhein on A. pleuropneumoniae was detected by fluorescence quantification of differential expression changes of key genes, and scanning electron microscopy was used to observe the changes in A. pleuropneumoniae status after Rhein treatment. Establishing a mouse model to observe the treatment of Rhein after A. pleuropneumoniae infection.Results. Here, in this study, we found that Rhein had a good killing effect on A. pleuropneumoniae and that the MIC was 25 µg ml-1. After 3 h of action, Rhein (4×MIC) completely kills A. pleuropneumoniae and Rhein has good stability. In addition, the treatment with Rhein (1×MIC) significantly reduced the formation of bacterial biofilms. Therapeutic evaluation in a murine model showed that Rhein protects mice from A. pleuropneumoniae and relieves lung inflammation. Quantitative RT-PCR (Quantitative reverse transcription polymerase chain reaction is a molecular biology technique that combines both reverse transcription and polymerase chain reaction methods to quantitatively detect the amount of a specific RNA molecule) results showed that Rhein treatment significantly downregulated the expression of the IL-18 (Interleukin refers to a class of cytokines produced by white blood cells), TNF-α, p65 and p38 genes. Along with the downregulation of genes such as IL-18, it means that Rhein has an inhibitory effect on the expression of these genes, thereby reducing the activation of inflammatory cells and the production of inflammatory mediators. This helps reduce inflammation and protects tissue from further damage.Conclusions. This study reports the activity of Rhein against A. pleuropneumoniae and its mechanism, and reveals the ability of Rhein to treat A. pleuropneumoniae infection in mice, laying the foundation for the development of new drugs for bacterial infections.","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140784171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Preliminary view of the distribution and spread of the plasmid-mediated resistance genes in Glaesserella parasuis 初步了解寄生褐青霉中质粒介导的抗性基因的分布和传播情况
IF 3 4区 医学 Q2 Medicine Pub Date : 2023-12-19 DOI: 10.1099/jmm.0.001767
Huarun Sun, Minghui Li, Yilin Bai, Yawei Sun, Chunling Zhu, Xiaojing Xia, Huihui Zhang, Weiyu Luo, Wei Zhang, Yuliang Wen, Yueyu Bai, Lei Wang and Jianhe Hu
Introduction. Various plasmid-mediated resistance genes have been reported in Glaesserella parasuis , but little is known about their global distribution features, evolution pattern and spread. Gap Statement. The potential mobilization mechanisms of resistance plasmids in G. parasuis have been poorly explored. Aim. The aim of the study was to investigate the prevalence and diversity of plasmid-mediated resistance genes among G. parasuis isolates, and focus on the analysis of the features of the resistance plasmids from G. parasuis . Method. The plasmids tested were sequenced using the Illumina HiSeq platform in conjunction with PCR and inverted PCR. The susceptibility of the host strains was determined by broth microdilution. The transfer of plasmids tested was conducted by electroporation. The sequence data were compared using bioinformatics tools and the data from our laboratory and the National Center for Biotechnology Information (NCBI) database. Results. Nineteen plasmids were identified from our laboratory and these resistance plasmids were functional and transferable. Moreover, we clustered five types of genetic backbones of plasmids from G. parasuis and revealed the global distribution features of the plasmid-mediated resistance genes. Conclusions. This is the first report of the coexistence of tet(H)-bearing type I plasmid and lnu(C)-bearing type II plasmid in one G. parasuis clinical isolate. In addition, this study provides the first view of the global distribution of plasmid-mediated resistance genes and classifies the plasmids in G. parasuis according to their backbone regions.
导言。据报道,寄生褐青苔菌中存在多种质粒介导的抗性基因,但人们对其全球分布特征、进化模式和传播方式知之甚少。差距说明。对寄生褐藻疽杆菌中抗性质粒的潜在动员机制研究甚少。研究目的本研究旨在调查寄生虫分离株中质粒介导的抗性基因的普遍性和多样性,重点分析寄生虫抗性质粒的特征。方法。使用 Illumina HiSeq 平台,结合 PCR 和反转 PCR 对检测的质粒进行测序。通过肉汤微稀释法测定宿主菌株的敏感性。测试质粒的转移是通过电穿孔法进行的。使用生物信息学工具比较了本实验室和美国国家生物技术信息中心(NCBI)数据库的序列数据。结果我们实验室鉴定出 19 个质粒,这些抗性质粒具有功能性和可转移性。此外,我们还对寄生虫质粒的五种遗传骨架进行了聚类,并揭示了质粒介导的抗性基因的全球分布特征。结论。这是首次报道在一个寄生虫临床分离株中同时存在携带 tet(H) 的 I 型质粒和携带 lnu(C) 的 II 型质粒。此外,这项研究还首次揭示了质粒介导的抗性基因在全球的分布情况,并根据主干区域对寄生虫中的质粒进行了分类。
{"title":"Preliminary view of the distribution and spread of the plasmid-mediated resistance genes in Glaesserella parasuis","authors":"Huarun Sun, Minghui Li, Yilin Bai, Yawei Sun, Chunling Zhu, Xiaojing Xia, Huihui Zhang, Weiyu Luo, Wei Zhang, Yuliang Wen, Yueyu Bai, Lei Wang and Jianhe Hu","doi":"10.1099/jmm.0.001767","DOIUrl":"https://doi.org/10.1099/jmm.0.001767","url":null,"abstract":"<span>Introduction</span>. Various plasmid-mediated resistance genes have been reported in <span> <span> Glaesserella parasuis </span> </span>, but little is known about their global distribution features, evolution pattern and spread. <span>Gap Statement</span>. The potential mobilization mechanisms of resistance plasmids in <span> <span> G. parasuis </span> </span> have been poorly explored. <span>Aim</span>. The aim of the study was to investigate the prevalence and diversity of plasmid-mediated resistance genes among <span> <span> G. parasuis </span> </span> isolates, and focus on the analysis of the features of the resistance plasmids from <span> <span> G. parasuis </span> </span>. <span>Method</span>. The plasmids tested were sequenced using the Illumina HiSeq platform in conjunction with PCR and inverted PCR. The susceptibility of the host strains was determined by broth microdilution. The transfer of plasmids tested was conducted by electroporation. The sequence data were compared using bioinformatics tools and the data from our laboratory and the National Center for Biotechnology Information (NCBI) database. <span>Results</span>. Nineteen plasmids were identified from our laboratory and these resistance plasmids were functional and transferable. Moreover, we clustered five types of genetic backbones of plasmids from <span> <span> G. parasuis </span> </span> and revealed the global distribution features of the plasmid-mediated resistance genes. <span>Conclusions</span>. This is the first report of the coexistence of <span>tet</span>(H)-bearing type I plasmid and <span>lnu</span>(C)-bearing type II plasmid in one <span> <span> G. parasuis </span> </span> clinical isolate. In addition, this study provides the first view of the global distribution of plasmid-mediated resistance genes and classifies the plasmids in <span> <span> G. parasuis </span> </span> according to their backbone regions.","PeriodicalId":16343,"journal":{"name":"Journal of medical microbiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138817280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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Journal of medical microbiology
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