48株鲍曼不动杆菌氨基糖苷类抗生素耐药基因检测

目的了解鲍曼不动杆菌氨基糖苷类抗生素耐药基因分布情况。方法收集蚌埠医学院第一附属医院2015年1月至12月临床分离的48株泛耐药鲍曼不动杆菌,VITEK 2Compact进行鉴定和药敏实验。PCR法检测12个氨基糖苷类修饰酶基因和3个甲基化酶基因以及外排泵基因adeB。结果在实验的16个基因中,共检出4种氨基糖苷类抗生素耐药基因aac(6′)-Ib、armA、adeB和ant(3″)-Ia,其中aac(6′)-Ib检出率为39.6%(19/48),armA基因检出率为89.6%(43/48),adeB检出率89.6%(43/48),ant(3″)-Ia检出率为10.4%(5/48),其余基因均未检出;存在两种以上耐药基因的共39株,检出率为81.3%(38/48)。结论 aac(6′)-Ib、armA基因以及外排泵adeB是介导我院鲍曼不动杆菌氨基糖苷类抗生素耐药的主要基因。     

鸭源大肠杆菌氨基糖苷类耐药基因的检测与传播扩散机制

目的探索鸭源大肠杆菌对氨基糖苷类耐药及耐药传播的分子机制。方法用微量稀释法测定鸭源大肠杆菌对氨基糖苷类药物的耐药表型,用PCR和DNA测序方法检测多种氨基糖苷修饰酶基因和质粒介导的16S甲基化酶基因,通过质粒接合试验分析有关耐药基因和耐药性的质粒接合传递特点,并采用基因克隆方法研究rmtB的基因环境。结果 27株分离菌中,有23株、19株、19株和18株分别对安普霉素、庆大霉素、阿米卡星和新霉素耐药,耐药率分别为85.2%、70.4%、70.4%和66.7%。27株中的13株检测到rmtB基因,6株同时检测到rmtB和aac(3)-IV基因。质粒接合试验获得5株接合子,接合子对安普霉素、庆大霉素、阿米卡星和新霉素均高水平耐药(MIC≥128μg/ml),rmtB基因检测呈阳性反应。结论鸭源大肠杆菌氨基糖苷类药物耐药和交叉耐药十分严重,质粒介导的rmtB基因和质粒接合传递是其耐药及其传播扩散的重要机制。     

呼吸道铜绿假单胞菌对氨基糖苷类抗生素药敏试验结果及耐药规律

目的了解呼吸道铜绿假单胞菌对氨基糖苷类抗生素敏感情况及耐药规律。方法收集并分析361株呼吸道铜绿假单胞菌对氨基糖苷类抗生素药敏资料,并探讨其耐药规律。结果本院呼吸道铜绿假单胞菌对阿米卡星最敏感,敏感率达82.2％。其次为奈替米星,敏感率46.3％。庆大霉素和妥布霉素的耐药率约60％。对4种抗生素同时敏感菌株为115株,占总数的31.9％,同时耐药菌株49株,占13.6％。对阿米卡星敏感而对其它3种抗生素耐药菌株79株,占21.9％。对阿米卡星和奈替米星敏感,而对另两种抗生素耐药菌株为41株,占11.4％。结论阿米卡星在氨基糖苷类抗生素中对铜绿假单胞菌最敏感。铜绿假单胞菌对4种抗生素存在不同程度交叉耐药,妥布霉素与庆大霉素交叉耐药更严重。     

鲍曼不动杆菌临床株中可移动遗传元件ISCR1的作用

目的了解鲍曼不动杆菌临床株中新型可移动遗传元件ISCR1的携带情况及其下游基因环境,探讨鲍曼不动杆菌耐药播散机理。方法收集多重耐药鲍曼不动杆菌临床株34株和敏感株21株,PCR扩增ISCR1基因及其下游的基因环境,扩增产物测序分析。结果 34株多重耐药鲍曼不动杆菌临床株中,携带ISCR1基因14株,其中11株ISCR1阳性多重耐药株,在ISCR1基因下游携带氨基糖甙类耐药基因armA基因;21株敏感株中,ISCR1基因扩增结果均为阴性。结论 ISCR1元件可能参与了armA耐药基因的水平播散。     

下呼吸道感染患者铜绿假单胞菌分离株氨基糖苷类耐药相关基因分析

目的探讨分离自下呼吸道感染患者的氨基糖苷类耐药铜绿假单胞菌的耐药机制。方法从下呼吸道感染患者痰液中分离出52株对氨基糖苷类耐药的铜绿假单胞菌,PCR法检测6种氨基糖苷类修饰酶(AMEs)基因,并检测其中泛耐药菌的6种16S rRNA甲基化酶基因(以下简称甲基化酶基因)。对阳性产物测序加以证实。结果 52株铜绿假单胞菌中检出4种AMEs基因[aac(3)-Ⅱ、aac(6’)-Ⅰb、aac(6’)-Ⅱ和ant(2″)-Ⅰ],AMEs基因总检出率为92.3%。泛耐药菌中检出1种甲基化酶基因(rmtB)。16株高水平泛耐药菌中rmtB基因的检出率为81.3%。结论分离自下呼吸道感染患者的氨基糖苷类耐药铜绿假单胞菌中AMEs基因携带率高,其对氨基糖苷类耐药与aac(3)-Ⅱ、aac(6’)-Ⅰb、aac(6’)-Ⅱ和ant(2″)-Ⅰ有关;对氨基糖苷类高水平泛耐药主要与甲基化酶基因rmtB有关。     

血流感染泛耐药鲍曼不动杆菌耐药和基因型分析

目的分析血流感染泛耐药鲍曼不动杆菌基因,指导临床疾病治疗及耐药性控制。方法从2013-2017年医院血流感染患者中分离泛耐药鲍曼不动杆菌,同一患者取首株。鉴定菌株并进行药敏试验,采用PCR进行基因检测。结果 2013-2017年检出血流感染泛耐药鲍曼不动杆菌共72株,各年份检出菌株数分别为4、7、13、21和27株,构成情况分别为5.56%、9.72%、18.06%、29.17%和37.50%。医院监护室、中心重症监护室、呼吸内科监护室、神经外科监护室、神经内科监护室、非监护室、肝胆外科、烧伤/整形科血流感染患者分别分离出19、11、9、6、5、5、4和3株,构成比分别为26.39%、15.28%、12.50%、8.33%、6.94%、6.94%、5.56%和4.17%;神经内科、胃肠外科、血管外科各2株,胸外科、肾脏内科、泌尿外科、神经外科各1株。泛耐药鲍曼不动杆菌对米诺环素、加替沙星耐药率分别为45.83%(33/72)、58.33%(42/72),对头孢他啶、头孢替坦、头孢曲松、头孢吡肟、庆大霉素、环丙沙星、阿米卡星、妥布霉素、头孢哌酮/舒巴坦的耐药率均为100.00%,对替加环素和多粘菌素B仍敏感,耐药率为0。aac(3)-I、aac(6′)-Ib、armA检出率分别为51.39%、31.94%和26.39%;blaTEM、blaSHV、blaCTX、blaIPM、blaVIM、OXA-23、OXA-51、ant(3′′)-I、aph3′-I、rmtB、carO缺失、adeB、adeG基因的检出率均为100.00%。结论血流感染泛耐药鲍曼不动杆菌检出情况逐年增加,尤其是监护室,临床治疗时可优先选用替加环素和多粘菌素B。控制耐药基因传播,可以从源头上控制泛耐药菌株传播,改善治疗效果。     

开放性胫腓骨骨折术后感染的病原菌及耐药情况分析

目的分析开放性胫腓骨骨折术后感染的病原菌及其耐药情况。方法对1890例开放性胫腓骨骨折患者的术后分泌物标本进行细菌培养和药敏试验。结果本组共检出阳性菌株1462株，其中G-杆菌1017株（69．54％），G^＋球菌349株（23．89％），真菌96株（6．57％）。其对B内酰胺类抗生素耐药率为15．5％-94．9％，对氨基糖苷类抗生素耐药率为36．6％～92．9％，未见万古霉素耐药菌株。结论开放性胫腓骨骨折术后感染以G-杆菌为主，对β内酰胺类、氨基糖苷类抗生素耐药性较高。     

耐亚胺培南鲍曼不动杆菌OXA-23基因检测及分析

目的了解临床分离的耐亚胺培南鲍曼不动杆菌OXA-23摹因的存在状况。方法收集我院临床分离的非重复耐亚胺培南鲍曼不动杆菌16株,采用纸片扩散法确定其耐药率,以PCR对亚胺培南耐药菌株进行OXA-23基因的检测并测序,序列与基因库比对。结果16株耐亚胺培南鲍曼不动杆菌中,OXA-23基因阳性11株,阳性率为68．8％。随机抽取2株OXA-23基因阳性株进行测序后,经网EGenBank比对,与OXA-23标准株100％同源。结论分离菌株主要来源于痰标本,耐亚胺培南鲍曼不动杆菌OXA-23雄因的携带率较高,分离菌株的耐药性可能与OXA-23型碳青霉烯酶基因有关。     

胸外科院内感染铜绿假单胞菌耐药性与耐药机制研究北大核心CSCD

目的 分析胸外科院内感染患者的病原菌分布情况、铜绿假单胞菌耐药性及耐药机制。方法 收集1 095例接受胸外科手术患者的送检标本,采用全自动细菌鉴定仪鉴定病原菌。采用K-B纸片扩散法对临床常见的12种抗生素进行药敏试验,测定52株铜绿假单胞菌的耐药性。采用PCR对18株耐氨基糖苷类铜绿假单胞菌的氨基糖苷类修饰酶基因和16SrRNA甲基化酶基因扩增,通过扩增产物分析耐药机制。结果 1 095例患者入院诊断主要为肺癌(30.32%)与食管癌(25.11%)。93例发生术后感染,感染98例次,感染率为8.49%,主要为下呼吸道感染(52.04%)。93例胸外科院内感染患者中,培养分离病原菌共115株。86株革兰阴性菌,主要为铜绿假单胞菌;22株革兰阳性菌,主要为金黄色葡萄球菌;7株真菌。52株铜绿假单胞菌对临床常见抗生素药敏试验显示,氨曲南、头孢他啶、环丙沙星、左氧氟沙星的耐药率>30%,多粘菌素B的敏感性为100.00%。52株铜绿假单胞菌中,18株对氨基糖苷类耐药,15株产氨基糖苷类修饰酶,主要为acc(6′)-Ⅱ阳性株。产氨基糖苷类修饰酶阳性基因模式主要为acc(6′)-Ⅰ+acc(6′)-Ⅱ+ant(2″)-Ⅰ+ant(3″)-Ⅰ。18株耐氨基糖苷类铜绿假单胞菌中,16SrRNA甲基化酶基因型72.22%为armA阳性。结论 本院胸外科院内感染率为8.49%,主要为下呼吸道感染,铜绿假单胞菌为主要病原菌。耐氨基糖苷类铜绿假单胞菌的耐药基因型主要为armA、acc(6′)-Ⅱ。     

部分非鲍曼不动杆菌耐药性及相关基因分析

目的了解目前非鲍曼不动杆菌临床分离株的耐药现状及耐药基因携带情况。方法随机抽取100株不动杆菌临床分离株,采用分子生物学方法筛选非鲍曼不动杆菌,用E-test方法检测非鲍曼不动杆菌对12种抗生素的耐药性,用PCR方法检测16种相关耐药基因的分布。结果共筛选出17株非鲍曼不动杆菌,7株为多重耐药(41.2%),其中对头孢噻肟的耐药率为100%,对氯霉素、哌拉西林、氨苄西林和氨曲南的耐药率分别为76.5%、76.5%、64.7%和52.9%,对多粘菌素B普遍敏感;检出6种耐药基因分别为ampC、blaTEM、blaPER-1、blaOXA-23-like、blaOXA-58和Int1。结论携带超广谱β-内酰胺酶(ESBLs)基因和blaOXA-23-like基因为非鲍曼不动杆菌对β-内酰胺类和碳青霉烯类抗生素耐药的主要原因。非鲍曼不动杆菌的耐药形势严峻,应加强监测。     

Control of intraabdominal hemorrhage and shock: a comparison of fluid resuscitation, MAST, and balloon occlusion

Our study examined the efficacy of four treatment modalities in controlling hemorrhage and achieving hemodynamic stabilization in hemorrhagic shock: intravenous fluid replacement (IV); military antishock trousers used concomitantly with fluids (MAST); balloon occlusion at the level of the diaphragm with concomitant fluid replacement (balloon); and a combination of MAST inflation, balloon occlusion, and fluid resuscitation (MAST and balloon). Twenty-eight mongrel dogs were anesthetized, and the spleen was exposed and completely crushed. The abdomen was closed, and treatment was initiated and continued for four hours or until the dog died. For all conditions the hematocrit dropped during the course of the experiment; balloon occlusion was effective at slowing this drop (P less than .0001), but MAST had no statistically significant effect. Animals with balloons bled more slowly into the abdominal cavity than did animals in the other two groups (P less than .0001). MAST also were effective at slowing the bleeding (P less than .05). Of the balloon and the MAST and balloon dogs, all except one survived the entire four hours; this difference between balloon and nonballoon dogs is significant (P = .002). MAST did not have a statistically significant effect on survival. Perfusion pressure (PP) declined during the course of the experiment, and the balloon was effective at slowing this decline (P less than .0001); none of the other comparisons was statistically significant.     

A Call to Action to Enhance Filovirus Disease Outbreak Preparedness and Response

The frequency and magnitude of recognized and declared filovirus-disease outbreaks have increased in recent years, while pathogenic filoviruses are potentially ubiquitous throughout sub-Saharan Africa. Meanwhile, the efficiency and effectiveness of filovirus-disease outbreak preparedness and response efforts are currently limited by inherent challenges and persistent shortcomings. This paper delineates some of these challenges and shortcomings and provides a proposal for enhancing future filovirus-disease outbreak preparedness and response. The proposal serves as a call for prompt action by the organizations that comprise filovirus-disease outbreak response teams, namely, Ministries of Health of outbreak-prone countries, the World Health Organization, Médecins Sans Frontières, the Centers for Disease Control and Prevention—Atlanta, and others.     

Interplay between interferon-mediated innate immunity and porcine reproductive and respiratory syndrome virus

Innate immunity is the first line of defense against viral infection, and in turn, viruses have evolved to evade host immune surveillance. As a result, viruses may persist in host and develop chronic infections. Type I interferons (IFN-α/β) are among the most potent antiviral cytokines triggered by viral infections. Porcine reproductive and respiratory syndrome (PRRS) is a disease of pigs that is characterized by negligible induction of type I IFNs and viral persistence for an extended period. For IFN production, RIG-I/MDA5 and JAK-STAT pathways are two major signaling pathways, and recent studies indicate that PRRS virus is armed to modulate type I IFN responses during infection. This review describes the viral strategies for modulation of type I IFN responses. At least three non-structural proteins (Nsp1, Nsp2, and Nsp11) and a structural protein (N nucleocapsid protein) have been identified and characterized to play roles in the IFN suppression and NF-κB pathways. Nsp's are early proteins while N is a late protein, suggesting that additional signaling pathways may be involved in addition to the IFN pathway. The understanding of molecular bases for virus-mediated modulation of host innate immune signaling will help us design new generation vaccines and control PRRS.     

Disease Pandemics and Major Epidemics Arising From New Encounters between Indigenous Viruses and Introduced Crops

Virus disease pandemics and epidemics that occur in the world’s staple food crops pose a major threat to global food security, especially in developing countries with tropical or subtropical climates. Moreover, this threat is escalating rapidly due to increasing difficulties in controlling virus diseases as climate change accelerates and the need to feed the burgeoning global population escalates. One of the main causes of these pandemics and epidemics is the introduction to a new continent of food crops domesticated elsewhere, and their subsequent invasion by damaging virus diseases they never encountered before. This review focusses on providing historical and up-to-date information about pandemics and major epidemics initiated by spillover of indigenous viruses from infected alternative hosts into introduced crops. This spillover requires new encounters at the managed and natural vegetation interface. The principal virus disease pandemic examples described are two (cassava mosaic, cassava brown streak) that threaten food security in sub-Saharan Africa (SSA), and one (tomato yellow leaf curl) doing so globally. A further example describes a virus disease pandemic threatening a major plantation crop producing a vital food export for West Africa (cacao swollen shoot). Also described are two examples of major virus disease epidemics that threaten SSA’s food security (rice yellow mottle, groundnut rosette). In addition, brief accounts are provided of two major maize virus disease epidemics (maize streak in SSA, maize rough dwarf in Mediterranean and Middle Eastern regions), a major rice disease epidemic (rice hoja blanca in the Americas), and damaging tomato tospovirus and begomovirus disease epidemics of tomato that impair food security in different world regions. For each pandemic or major epidemic, the factors involved in driving its initial emergence, and its subsequent increase in importance and geographical distribution, are explained. Finally, clarification is provided over what needs to be done globally to achieve effective management of severe virus disease pandemics and epidemics initiated by spillover events.     

Barrett's Esophagus: Where Do We Stand?

Barrett''s esophagus (BE) is a precursor for esophageal adenocarcinoma, which has an increased incidence rate over the last few decades. Its importance stems from the poor five-year survival of esophageal adenocarcinoma and current data that suggest a survival benefit when surveillance programs are implemented. In this review, we will cover the pathophysiology and natural history of BE and the different endoscopic findings. The prevalence of BE in different geographic areas and the incidence of high-grade dysplasia and adenocarcinoma in this patient population is reviewed. Recent recommendation for screening and surveillance of BE has been covered in this review as well as the efficacy of nonconventional imaging modalities and endoscopic ablation therapies.     

The Technology Transfer from Europe to China in the 17th–18th Centuries: Non-Invasive On-Site XRF and Raman Analyses of Chinese Qing Dynasty Enameled Masterpieces Made Using European Ingredients/Recipes

Two masterpieces of the Qing Dynasty (1644–1912 CE), one in gilded brass (incense burner) decorated with cloisonné enamels stylistically attributed to the end of the Kangxi Emperor’s reign, the other in gold (ewer offered by Napoleon III to the Empress as a birthday present), decorated with both cloisonné and painted enamels bearing the mark of the Qianlong Emperor, were non-invasively studied by optical microscopy, Raman microspectroscopy and X-ray microfluorescence spectroscopy (point measurements and mapping) implemented on-site with mobile instruments. The elemental compositions of the metal substrates and enamels are compared. XRF point measurements and mappings support the identification of the coloring phases and elements obtained by Raman microspectroscopy. Attention was paid to the white (opacifier), blue, yellow, green, and red areas. The demonstration of arsenic-based phases (e.g., lead arsenate apatite) in the blue areas of the ewer, free of manganese, proves the use of cobalt imported from Europe. The high level of potassium confirms the use of smalt as the cobalt source. On the other hand, the significant manganese level indicates the use of Asian cobalt ores for the enamels of the incense burner. The very limited use of the lead pyrochlore pigment (European Naples yellow recipes) in the yellow and soft green cloisonné enamels of the Kangxi incense burner, as well as the use of traditional Chinese recipes for other colors (white, turquoise, dark green, red), reinforces the pioneering character of this object in technical terms at the 17th–18th century turn. The low level of lead in the cloisonné enamels of the incense burner may also be related to the use of European recipes. On the contrary, the Qianlong ewer displays all the enameling techniques imported from Europe to obtain a painted decoration of exceptional quality with the use of complex lead pyrochlore pigments, with or without addition of zinc, as well as cassiterite opacifier.     

Formoterol Delivered via the Dry Powder Aerolizer® Inhaler Versus Albuterol MDI and Placebo in Mild-to-Moderate Asthma: A Randomized, Double-Blind, Double-Dummy Trial

The objectives of this study were to compare the efficacy and tolerability of twice-daily formoterol dry powder 12 µg and 24 µg (Foradil) delivered via Aerolizer inhaler with four times daily albuterol (salbutamol) 180 µg delivered via metered dose inhaler (MDI) and placebo. A total of 554 adolescents and adults (ages 12-75 years) with mild-to-moderate asthma were randomized to this 12-week, multicenter, double-blind, double-dummy, placebo-controlled, parallel-group study. Twelve-hour spirometry measurements were taken at weeks 0, 4, 8, and 12. A total of 484 patients completed the study (122, 116, 127, and 119 given formoterol 12 µg, formoterol 24 µg, albuterol, and placebo, respectively). For the primary efficacy variable, the forced expiratory volume in 1 second (FEV₁), both formoterol 12 µg and 24 µg were statistically superior to placebo at all time points on all test days (p ≤ 0.017) and to albuterol at most time points on all test days (p ≤ 0.001). The onset of improvement in FEV₁ was rapid, with 15% increase within 5 min in 57%, 71%, and 65% of formoterol 12 µg, formoterol 24 µg, and albuterol patients, respectively. Formoterol was also superior to placebo and albuterol in terms of secondary efficacy variables: FEV₁ area under the curve, percentage of predicted FEV₁, forced vital capacity and forced expiratory flow, asthma symptom scores, and peak expiratory flows. In conclusion, both formoterol doses were superior to placebo in all lung function measurements. Overall, compared with albuterol, both formoterol doses produced superior bronchodilation. Formoterol and albuterol were safe and well-tolerated.