血清白细胞介素-6检测对血流感染诊断价值的探讨

目的探讨血清白细胞介素-6（IL-6）水平对鉴别革兰阴性菌（G-）、革兰阳性菌（G＋）及真菌血流感染在临床中的诊断价值。方法收集从2015年1月至2016年3月入院血流感染患者的资料,所有患者血培养为单一菌株并于采血当天检测血清IL-6水平,同时选取血培养阴性的局部感染患者30例作为对照组,比较IL-6水平在G-菌、G＋菌及真菌血流感染患者之间的差异,并根据受试者工作特征（ROC）曲线判断IL-6诊断效能。结果 170例血流感染患者中,G-菌感染75例（占44%）、G＋菌感染67例（占40%）及真菌感染28例（占16%）;G-菌组、G＋菌组、真菌组及对照组IL-6水平中位数分别为221.3pg/m L、37.4 pg/m L、111.0 pg/m L和3.87 pg/m L,各组间IL-6水平差异有统计学意义（P57.585pg/m L时,G-菌感染可能性大;IL-6对鉴别真菌所致血流感染患者无临床参考价值,有待相关新指标的发现及评估。     

注射用头孢拉宗钠的体内外抗菌活性研究

目的评价注射用头孢拉宗钠的体内外抗菌活性。方法选取663株临床分离致病菌为实验菌,以头孢美唑、头孢西丁、头孢替坦、头孢米诺、头孢唑啉、头孢呋辛、头孢哌酮、头孢吡肟为对照药物,分别采用平皿二倍稀释法测定药物最低抑菌浓度（MIC）、最低杀菌浓度（MBC）、绘制杀菌曲线（KCs）并行诱导耐药实验,观察头孢拉宗的体外抗菌作用;建立小鼠腹腔感染模型,评价头孢拉宗皮下给药对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌感染小鼠的体内疗效。结果头孢拉宗对多种革兰阴性菌具有较高的抗菌活性,尤以对大肠埃希菌和肺炎克雷伯杆菌的抗菌活性更为突出,其MIC50、MIC90分别为0.5、8μg/ml,对产超广谱β-内酰胺酶大肠埃希菌和肺炎克雷伯杆菌的抗菌活性也较强,其MIC50、MIC90分别为4、8μg/ml;头孢拉宗对革兰阴性菌的抗菌作用大多优于头孢西丁、头孢美唑、头孢唑啉、头孢哌酮、头孢替坦和头孢呋辛,而对革兰阳性菌的抗菌活性较弱,与头孢替坦和头孢米诺相近。MBC和KCs测定结果表明,头孢拉宗对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌均具有杀菌作用。以1/4MIC剂量诱导20d后,头孢拉宗对金黄色葡萄球菌、大肠埃希菌和肺炎克雷伯杆菌的抗菌活性无明显改变。头孢拉宗皮下给药对大肠埃希菌ATCC25922、大肠埃希菌1515、肺炎克雷伯杆菌7、肺炎克雷伯杆菌9613感染小鼠的体内疗效明显优于头孢美唑和头孢唑啉（均P〈0.01）;对金黄色葡萄球菌感染小鼠的体内疗效与头孢美唑相近（P〉0.05）,但弱于头孢唑啉（P〈0.01）。结论注射用头孢拉宗钠对多数革兰阴性菌,特别是大肠埃希菌和肺炎克雷伯杆菌具有较强的体外抗菌活性;同时对大肠埃希菌、肺炎克雷伯杆菌、金黄色葡萄球菌腹腔感染小鼠的体内疗效也较好。     

Synergistic Antimicrobial Activities of Phytoestrogens in Crude Extracts of Two Sesame Species Against Some Common Pathogenic Microorganisms

Intensive studies on extracts and biologically active compounds isolated from medicinal plants have doubled in the last decade worldwide. However, as a result of paucity of knowledge and folkloric claim on the effectiveness of sesame leaves in infectious disease treatments, we aimed to determine the synergistic antimicrobial activity of essential oils and lignans present in the crude leaves extracts of Sesame radiatum and Sesame indicum. Ethanolic, methanolic and aqueous extracts of both leaves were studied for their in-vitro synergistic antimicrobial activity against both Gram positive and Gram negative micro-organisms, and Yeast using Agar diffusion method. The GC-MS phytochemical screening of methanolic extract showed that the major compounds in essential oils are of carboxylic acids and phenolic groups especially, the most potent antioxidants known to man like sesamol, sesamolin and sesamin among others. Methanolic and ethanolic extracts have broad spectrum antimicrobial effect against all the tested pathogenic micro-organisms except Streptococcus pneumoniae and Staphylococcus aureus respectively, while the aqueous extract exhibited inhibitory activity on Staphylococcus aureus, Streptococcus pneumoniae and Candida albicans. The result confirmed the folkloric claims of the antimicrobial effectiveness of locally consumed sesame leaves extracts especially against bacterial and common skin infection in many areas of Nigeria.     

甘肃省某三甲医院糖尿病足患者创面感染病原菌及相关因素分析

目的探讨甘肃省某三甲医院收治的糖尿病足患者创面感染病原菌情况,分析创面感染的相关因素,为后期临床救治提供理论依据。 方法选择2017年1月至2021年12月甘肃省人民医院收治的符合入选标准的糖尿病足患者,收集并分析患者的人口信息(年龄、性别)、糖尿病足创面特征(糖尿病病程、创面持续时间、创面部位)、抗生素应用数量、实验室检测指标(红细胞计数、白细胞计数、血红蛋白、白蛋白、肌酐、胆固醇、甘油三脂、高密度脂蛋白、低密度脂蛋白、空腹血糖、糖化血红蛋白、白细胞介素-6、降钙素原)、创面细菌培养结果及药物敏感试验结果。数据比较采用χ²检验、单因素分析、多因素Logistic回归分析。 结果(1)本研究共纳入糖尿病足患者173例,其中51~60岁人数最多,有53例,占比30.6%,其次为61~70岁、41~50岁、71~80岁,分别占24.3%、20.2%、16.8%;男性总体多于女性,男性138例,占比79.8%,女性35例,占比20.2%。(2)糖尿病足患者糖尿病病程10~14年人数最多,38例,占比为22.0%,创面持续时间中人数最多为15~30 d,53例,占比为30.1%。173例患者共185个创面,其中位于足趾部位最多,有68例,占比36.8%,其次为足底52例,占比28.1%。(3)患者的实验室检测指标结果显示,红细胞计数低于正常值范围的患者占比60.1%,白细胞计数高于正常值范围的患者占比34.7%,血红蛋白低于正常值范围的患者占比42.8%,白蛋白低于正常值范围的患者占比86.1%,肌酐高于正常值范围的患者占比20.8%,胆固醇高于正常值范围的患者占比11.6%,甘油三酯高于正常值范围的患者占比23.7%,高密度脂蛋白低于正常值范围的患者占比73.4%,低密度脂蛋白高于正常值范围的患者占比12.7%,空腹血糖高于正常值范围的患者占比82.1%,糖化血红蛋白高于正常值范围的患者占比77.5%,白细胞介素-6高于正常值范围的患者占比77.5%,降钙素原高于正常值范围的患者占比68.2%。(4)173例患者共送检标本257份,其中阳性210份,阴性47份,阳性率81.7%;其中革兰阳性菌共120株,占比57.1%,革兰阴性菌共89株,占比42.4%,真菌1株,占比0.5%;革兰阳性菌中金黄色葡萄球菌65株,占比最高,为31.0%,其次是粪肠球菌16株,占比7.6%;革兰阴性菌中阴沟肠杆菌24株,占比最高,为11.4%,其次是大肠埃希菌21株,占比10.0%;药物敏感试验结果显示,金黄色葡萄球菌对甲氧苄啶/磺胺甲恶唑、万古霉素、利奈唑胺等抗生素较为敏感,敏感率均为100.0%;其对青霉素耐药率高,耐药率为89.2%,其次为克林霉素和红霉素,耐药率分别为78.5%、76.9%;阴沟肠杆菌对美洛培南、厄他培南、头孢哌酮/舒巴坦、左旋氧氟沙星等较为敏感,敏感率均为100.0%,其次为阿米卡星、亚胺培南、头孢吡肟,敏感率均为95.8%;大肠埃希菌对美洛培南、厄他培南、亚胺培南、替加环素、头孢西丁、阿米卡星等较为敏感,敏感率均为100.0%。173例患者中,抗生素应用数量为0的有19例,占比11.0%;1种及2种的均有61例,占比均为35.3%;3种的有25例,占比14.4%;4种以上7例,占比4.0%。(5)对糖尿病足患者感染的17个相关因素进行单因素分析,结果显示,创面持续时间、抗生素应用数量、白细胞计数、血红蛋白、白蛋白、高密度脂蛋白、肌酐、糖化血红蛋白、白细胞介素-6、降钙素原等相关因素差异均有统计学意义(P<0.05);进一步行多因素Logistic回归分析结果显示,与创面感染相关的因素有创面持续时间、抗生素应用数量,高密度脂蛋白(OR＝1.530、1.923、2.587,P<0.05)。 结论糖尿病足患者创面病原菌培养中,革兰阳性菌中以金黄色葡萄球菌、粪肠球菌为主,而革兰阴性菌以阴沟肠杆菌、大肠埃希菌为主;糖尿病足患者感染的独立危险因素为创面形成时间长、抗生素滥用,高密度脂蛋白低。     

Gram-Negative, but Not Gram-Positive, Bacteria Elicit Strong PGE2 Production in Human Monocytes

Gram-positive and Gram-negative bacteria induce different cytokine patterns in human mononuclear cells. We have seen that Gram-positives preferentially induce IL-12 and TNF-alpha, whereas Gram-negatives induce more IL-10, IL-6, and IL-8. In this study, we compared the capacity of these two groups of bacteria to induce PGE2. Monocytes stimulated with Gram-negative bacterial species induced much more PGE2 than did Gram-positive bacteria (5600 +/- 330 vs. 1700 +/- 670 pg/mL, p < 0.001). Blocking of COX-2 by NS398 abolished PGE2 production, but did not alter the cytokine patterns induced by Gram-positive and Gram-negative bacteria. We suggest that Gram-positive and Gram-negative bacteria may stimulate different innate effector functions; Gram-positive bacteria promoting cell-mediated effector functions whereas Gram-negative bacteria inducing mediators inhibiting the same.     

长效抗菌材料对留置导尿管患者感染病原菌及血清炎症因子的影响

BACKGROUND: Long-acting antimicrobial material is a new polymer activator of organosilicon quaternary ammonium salt and has obvious advantages in anti-infection.     

亚胺培南对医院内革兰阴性菌的抗菌活性分析

目的:了解亚胺培南对院内革兰阴性菌的抗菌活性。方法:收集2007年至2011年从临床送检标本中分离出来的革兰阴性菌4264株,采用Vitek 2全自动微生物鉴定分析系统、API系统及K-B法进行培养鉴定和药敏试验。结果:发现亚胺培南总耐药率为25.82%(1101/4264),2007年至2011年的年度耐药率分别为4.23%(8/189),9.23%(35/379),10.12%(49/484),24.12%(179/742)和33.60%(830/2470);耐药菌种分别占总菌种数的28.57%(4/14),40.00%(8/20),31.25%(5/16),36.36%(8/22)和65.71%(23/35)。分离率前10位的是大肠埃希菌、鲍曼不动杆菌、肺炎克雷伯菌、铜绿假单胞菌、阴沟肠杆菌、产气肠杆菌、洋葱伯克霍尔德菌、黏质沙雷菌、产酸克雷伯菌和甲型副伤寒沙门菌,对亚胺培南的耐药率分别为0.82%(9/1097),68.22%(631/925),4.07%(29/713),39.86%(228/572),9.64%(27/280),2.40%(3/125),90.00%(81/90),7.02%(4/57),46.43%(26/56)和0(0/45)。2007年至2011年对亚胺培南的年度耐药率,铜绿假单胞菌为6.25%(1/16),31.25%(5/16),19.57%(9/46),34.48%(40/116)和45.77%(173/378);鲍曼不动杆菌为7.14%(1/14),47.06%(8/17),29.63%(8/27),61.45%(110/179)和73.26%(504/688);阴沟肠杆菌为0(0/10),0(0/26),3.13%(1/32),9.23%(6/65)和13.61%(20/147)。大肠埃希菌、肺炎克雷伯菌、产气肠杆菌、黏质沙雷菌在最近1～2年检出了亚胺培南耐药菌株。结论:亚胺培南是一种有效的抗革兰氏阴性菌药物,但药敏性正在逐年下降,耐药菌种数在增多,耐药率正在逐年上升。     

The rise and spread of mcr plasmid-mediated polymyxin resistance

Polymyxins are important lipopeptide antibiotics that serve as the last-line defense against multidrug-resistant (MDR) Gram-negative bacterial infections. Worryingly, the clinical utility of polymyxins is currently facing a serious threat with the global dissemination of mcr, plasmid-mediated polymyxin resistance. The first plasmid-mediated polymyxin resistance gene, termed as mcr-1 was identified in China in November 2015. Following its discovery, isolates carrying mcr, mainly mcr-1 and less commonly mcr-2 to -7, have been reported across Asia, Africa, Europe, North America, South America and Oceania. This review covers the epidemiological, microbiological and genomics aspects of this emerging threat to global human health. The mcr has been identified in various species of Gram-negative bacteria including Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Salmonella enterica, Cronobacter sakazakii, Kluyvera ascorbata, Shigella sonnei, Citrobacter freundii, Citrobacter braakii, Raoultella ornithinolytica, Proteus mirabilis, Aeromonas, Moraxella and Enterobacter species from animal, meat, food product, environment and human sources. More alarmingly is the detection of mcr in extended-spectrum-β-lactamases- and carbapenemases-producing bacteria. The mcr can be carried by different plasmids, demonstrating the high diversity of mcr plasmid reservoirs. Our review analyses the current knowledge on the emergence of mcr-mediated polymyxin resistance.     

Both membrane-bound and soluble forms of CD14 bind to Gram-negative bacteria

Tissue macrophages and their precursors – the blood monocytes – respond rapidly to a bacterial infection with the release of inflammatory mediators. These mediators are involved in the recruitment of phagocytic cells, principally neutrophils, from the blood to the site of infection. To initiate this process macrophages and monocytes must be able to detect the presence of bacteria in a reliable, but nevertheless nonspecific, fashion. It is thought that this is achieved by means of receptors on the cell surface which recognize structures common to many different bacteria. One candidate for such a “pattern recognition element” is the cell surface glycoprotein CD 14. CD 14 has been shown to bind components of the Gram-positive cell wall and it also binds soluble lipopolysaccharide released from Gram-negative bacteria. In both cases the interaction with CD 14 leads to an activation of the cell. Here we show that human peripheral blood monocytes can, in addition, bind intact Gram-negative bacteria in the presence of serum and that this process involves CD14. When CD14 expression is induced on the myelomonocytic cell line U937 by treatment with vitamin D3 the cells concomittently acquire the capacity to bind bacteria. Furthermore, a non-monocytic cell line which does not bind bacteria acquires the capacity to do so when transfected with either the human or mouse CD14 gene. This binding can be inhibited by blocking the CD14 receptor with anti-CD14 antibody or by blocking the ligand on the bacteria with soluble CD14. Finally we demonstrate binding of sCD14 to Escherichia coli. We conclude that in the presence of serum both membrane-bound and soluble forms of CD14 can bind to Gram-negative bacteria. This suggests that CD14 may play a role in the detection and elimination of intact bacteria in vivo.     

夫西地酸乳膏在常见皮肤病中的应用

夫西地酸乳膏是一种外用的抗菌药物制剂,具有抑菌和免疫调节双重功效。在皮肤病理状态下,夫西地酸乳膏能够渗透入深层皮肤,进入感染病灶,具有良好的临床疗效和安全性。本文详细介绍了夫西地酸的作用机理,并结合文献报道说明夫西地酸乳膏在皮肤科应用的范围,包括痤疮、儿童脓疱疮、湿疹、细菌性感染皮肤病及红癣等。     

烧伤患者医院感染病原菌分布及耐药变迁分析

目的了解烧伤病房感染病原菌分布及耐药变迁特点。方法回顾海南省人民医院2002-2009年住院烧伤感染患者病原菌的分布,并对比前、后4年病原菌构成比及耐药情况。结果检出634株病原菌,其中革兰阴性（G-）杆菌389株（61.4%）,主要为铜绿假单胞菌196株（30.9%）、鲍曼不动杆菌89株（14.0%）和大肠埃希菌56株（8.8%）;革兰阳性（G＋）球菌220株（34.7%）,主要为金黄色葡萄球菌109株（17.2%）和表皮葡萄球菌79株（12.5%）;真菌25株（3.9%）。前、后4年里,铜绿假单胞菌及金黄色葡萄球菌的构成比有下降趋势（P〈0.05）,而条件致病菌如鲍曼不动杆菌、表皮葡萄球菌的构成比呈明显上升趋势（P〈0.01）;铜绿假单胞菌、鲍曼不动杆菌对第三代头孢菌素、喹诺酮类抗生素的耐药率有上升趋势（P〈0.05）。109株金黄色葡萄球菌中耐甲氧西林金黄色葡萄球菌（MRSA）52株（47.8%）,对万古霉素100%敏感。结论近8年来烧伤病房患者感染病原菌以G-杆菌为主,条件致病菌的检出率呈上升趋势;常见病原菌对第三代头孢菌素的耐药率呈上升趋势,对此应予以重视。     

Clinical Impact of Pretransplant Multidrug-Resistant Gram-Negative Colonization in Autologous and Allogeneic Hematopoietic Stem Cell Transplantation

Multidrug-resistant Gram-negative bacteria (MDR-GNB) are an emerging cause of morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Three-hundred forty-eight consecutive patients transplanted at our hospital from July 2012 to January 2016 were screened for a pretransplant MDR-GNB colonization and evaluated for clinical outcomes. A pretransplant MDR-GNB colonization was found in 16.9% of allo-HSCT and in 9.6% of auto-HSCT recipients. Both in auto- and in allo-HSCT, carriers of a MDR-GNB showed no significant differences in overall survival (OS), transplant-related mortality (TRM), or infection-related mortality (IRM) compared with noncarriers. OS at 2 years for carriers compared with noncarriers was 85% versus 81% (P?=?.262) in auto-HSCT and 50% versus 43% (P?=?.091) in allo-HSCT. TRM at 2 years was 14% versus 5% (P?=?.405) in auto-HSCT and 31% versus 25% (P?=?.301) in allo-HSCT. IRM at 2 years was 14% versus 2% (P?=?.142) in auto-HSCT and 23% versus 14% (P?=?.304) in allo-HSCT. In multivariate analysis, only grade III to IV acute graft-versus-host disease was an independent factor for reduced OS (P?<?.001) and increased TRM (P?<?.001) and IRM (P?<?.001). During the first year after transplant, we collected 73 GNB bloodstream infectious (BSI) episodes in 54 patients, 42.4% of which sustained by a MDR-GNB. Rectal swabs positivity associated with the pathogen causing subsequent MDR-GNB BSI episodes in 13 of 31 (41.9%). Overall, OS at 4 months from MDR-GNB BSI episode onset was of 67.9%, with a 14-day attributed mortality of 12.9%, not being significantly different between carriers and noncarriers (P?=?.207). We conclude that in this extended single-center experience, a pretransplant MDR-GNB colonization did not significantly influence OS, TRM, and IRM both in auto- and allo-HSCT settings and that MDR-GNB attributed mortality can be controlled in carriers when an early pre-emptive antimicrobial therapy is started in case of neutropenic fever.     

Detection of the common resistance genes in Gram-negative bacteria using gene chip technology

Objective: To design a resistance gene detection chip that could, in parallel, detect common clinical drug resistance genes of Gram-negative bacteria. Materials and Methods: Seventy clinically significant Gram-negative bacilli (Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae, Pseudomonas aeruginosa, Acinetobacter baumannii) were collected. According to the known resistance gene sequences, we designed and synthesized primers and probes, which were used to prepare resistance gene detection chips, and finally we hybridized and scanned the gene detection chips. Results: The results between the gene chip and polymerase chain reaction (PCR) were compared. The rate was consistently 100% in the eight kinds of resistance genes tested (TEM, SHV, CTX-M, DHA, CIT, VIM, KPC, OXA-23). One strain of Pseudomonas aeruginosa had the IMP, but it was not found by gene chip. Conclusion: The design of Gram-negative bacteria-resistant gene detection chip had better application value.     

革兰氏阳性细菌铁摄取机制的研究进展

铁是大多数细菌生长存活的基本营养物质,细菌能否从宿主体内摄取足够的铁对于其毒力和致病起着关键的作用.铁在宿主体内主要以游离铁、含铁蛋白和血红素三种形式存在.细菌可以通过复杂的铁摄取机制来获得宿主体内的铁进而感染宿主.因此,探究细菌的铁摄取机制有助更好的了解细菌的生长和致病过程.     

Purification of membrane vesicles from Gram-positive bacteria using flow cytometry,after iodixanol density-gradient ultracentrifugation

Membrane vesicles (MVs) play biologically important roles in Gram-positive bacteria, and purification is essential for their study. Although high-performance flow cytometry has the capability to quantify and isolate specific small particles, it has not been examined for MV isolation. In this study, we used high-performance flow cytometry to analyze MV from Gram-positive bacteria, Staphylococcus aureus and Bacillus subtilis, prepared by iodixanol density-gradient ultracentrifugation. Analysis of the quality of MV samples before and after sorting showed that the flow cytometric sorting provided higher purity and uniformity compared to gradient isolation alone. The MV purification method using flow cytometry should prove useful for applications requiring a very high purity of MV samples such as proteomic, metagenomic or lipidomic studies.     

Functional comparison of the mouse DC-SIGN, SIGNR1, SIGNR3 and Langerin, C-type lectins

The mouse (m) DC-SIGN family consists of several homologous type II transmembrane proteins located in close proximity on chromosome 8 and having a single carboxyl terminal carbohydrate recognition domain. We first used transfected non-macrophage cell lines to compare the polysaccharide and microbial uptake capacities of three of these lectins--DC-SIGN, SIGNR1 and SIGNR3--to another homologue mLangerin. Each molecule shares a potential mannose-recognition EPN-motif in its carbohydrate recognition domain. Using an anti-Tag antibody to follow Tag-labeled transfectants, we found that each molecule could be internalized, although the rates differed. However, mDC-SIGN was unable to take up FITC-dextran, FITC-ovalbumin, zymosan or heat-killed Candida albicans. The other three lectins showed distinct carbohydrate recognition properties, assessed by blocking FITC-dextran uptake at 37 degrees C and by mannan binding activity at 4 degrees C. Furthermore, only SIGNR1 was efficient in mediating the capture by transfected cells of Gram-negative bacteria, such as Escherichia coli and Salmonella typhimurium, while none of the lectins tested were competent to capture Gram-positive bacteria, Staphylococcus aureus. Interestingly, transfectants with SIGNR1 lacking the cytoplasmic domain were capable of binding FITC-zymosan in a manner that was abolished by EDTA or mannan, but not laminarin. In addition, resident peritoneal CD11b+ cells expressing SIGNR1 bound zymosan at 4 degrees C in concert with a laminarin-sensitive receptor. Therefore these homologous C-type lectins have distinct recognition patters for microbes despite similarities in the carbohydrate recognition domains.