铜绿假单胞菌氨基糖苷类药物修饰酶基因研究

目的 调查铜绿假单胞菌对常用抗生素的耐药特性及氨基糖苷类药物修饰酶基因表达。方法 用Phoenix^TM-100系统鉴定细菌和药敏试验。用琼脂扩散法检测20株多重耐药铜绿假单胞菌对阿米卡星、庆大霉素、妥布霉素和奈替米星4种药物的敏感性。采用聚合酶链反应（PCR）扩增4种氨基糖苷类药物修饰酶基因,并使用DNA测序加以证实。结果 190株铜绿假单胞菌对氯霉素、四环素、复方磺胺耐药率最高,均为98．9％;对亚胺培南、美洛培南的耐药率分别为15．3％和6．8％。从20株菌中检出aac（6′）-Ⅰ、aac（6′）-Ⅱ和ant（2″）-Ⅰ3种修饰酶基因,阳性率分别为10％、60％和65％,未发现ant（3″）-Ⅰ基因。20株菌对阿米卡星、庆大霉素、妥布霉素和奈替米星的耐药率分别为35．0％、90．0％、70．0％、60．0％。结论 本地区铜绿假单胞菌对氨基糖苷类药物的耐药与修饰酶基因的传播表达有关。     

多重耐药铜绿假单胞菌对氨基糖苷类药物耐药研究

目的探讨宜兴市第二人民医院临床分离多重耐药铜绿假单胞菌与氨基糖苷类抗菌药物的表型与基因型的关系,为临床抗感染治疗提供依据。方法采用琼脂纸片扩散(K-B)法对临床分离的铜绿假单胞菌进行药敏试验,选出34株多重耐药菌株,用聚合酶链反应(PCR)法检测氨基糖苷类修饰酶基因。结果氨基糖苷类修饰酶基因aac(3)-Ⅱ、ant(2′)-Ⅰ、ant(3′)-Ⅰ、aac(6′)-Ⅱ、aac(6′)-Ⅰ检出阳性率分别为85.3%、44.1%、17.6%、11.8%、5.9%。对庆大霉素、阿米卡星、妥布霉素、奈替米星的耐药率分别为91.18%、44.12%、88.24%、85.29%。结论多重耐药铜绿假单胞菌对氨基糖苷类抗菌药物的耐药程度不同,临床应根据药敏结果选择用药,以减少耐药菌株的产生,控制院内感染。     

ICU多重耐药铜绿假单胞菌产氨基糖苷类修饰酶基因的研究

目的探讨重症监护室多重耐药铜绿假单胞菌产氨基糖苷类修饰酶基因的表达。方法采用PCR检测60株多重耐药铜绿假单胞菌的4种氨基糖苷类修饰酶基因ant(2″)-Ⅰ、ant(3″)-Ⅰ、anc(6′)-Ⅰ和anc(6′)-Ⅱ。结果 60株多重耐药铜绿假单胞菌中检测到含有氨基糖苷类修饰酶基因的菌株共16株,检出率为26.67%(16/60);8株含ant(2″)-Ⅰ基因,检出率为13.33%(8/60);10株含有anc(6′)-Ⅱ基因,检出率为16.67%(10/60);其中两株同时含ant(2″)-Ⅰ基因和anc(6′)-Ⅱ基因,未检测出ant(3″)-Ⅰ和anc(6′)-Ⅰ基因。结论重症监护室多重耐药铜绿假单胞菌中氨基糖苷类修饰酶基因的表达率较高,氨基糖苷类修饰酶介导的耐药在多重耐药铜绿假单胞菌的耐药机制中占有重要的地位。     

多重耐药铜绿假单胞菌氨基糖苷类修饰酶基因的检测及分析

目的 探讨多重耐药铜绿假单胞菌的氨基糖苷类药物的耐药机制.方法 分离出50株多重耐药铜绿假单胞菌,PCR法检测4种氨基糖苷类修饰酶(AMEs)基因,即aac(6′)-Ⅰ、aac(6′)-Ⅱ、ant(3″)-Ⅰ、ant(2″)-Ⅰ的表达情况.并用MLVA基因分型的方法对菌株进行聚类分析.结果 50株铜绿假单胞菌中,4种AMEs基因的总检出率为70%.aac(6′)-Ⅰ、aac(6′)-Ⅱ、ant(3″)-Ⅰ、ant(2″)-Ⅰ的检出率分别为60%、40%、24%、32%.MLVA基因分析聚类结果显示,没有多重耐药铜绿假单胞菌的暴发流行.结论 多重耐药铜绿假单胞菌的AMEs基因携带率较高,没有发现其爆发流行.     

铜绿假单胞菌氨基糖苷类修饰酶基因与耐药表型的研究

目的探讨临床分离的22株铜绿假单胞菌（Pa）氨基糖苷类修饰酶（AMES）基因与耐药表型的关系。方法对22株铜绿假单胞菌采用稀释法检测庆大霉素、阿米卡星、奈替米星、妥布霉素4种抗菌药物的最低抑菌浓度（MIC），并用聚合酶链反应（PCR）法检测6种氨基糖苷类修饰酶基因。结果本组22株Pa菌庆大霉素耐药15株（68．2％）、阿米卡星耐药3株（13．6％）、奈替米星14株（63．6％）、妥布霉素15株（68．2％），检出aac（3）-Ⅰ阳性14株（63．6％）、aac（6’）-Ⅰ阳性5株（22．7％）、aac（6’）-Ⅱ阳性3株（13．6％）、ant（3”）-Ⅰ阳性1株（4．5％）和ant（2”）-Ⅰ阳性7株（31．8％），aac（3）．Ⅰ为阴性。共有18株检出氨基糖苷类修饰酶基因（81．8％）。结论分离自临床的铜绿假单胞菌氨基糖苷类修饰酶基因检出率高，且与耐药表型一致。     

铜绿假单胞菌16S rRNA甲基化酶基因和氨基糖苷修饰酶基因的研究

目的了解氨基糖苷类抗菌药物耐药的铜绿假单胞菌16S r RNA甲基化酶基因和氨基糖苷修饰酶基因的携带情况,探讨铜绿假单胞菌对氨基糖苷类药物的耐药机制。方法收集临床分离的氨基糖苷类抗菌药物耐药的铜绿假单胞菌35株,采用VITEK 2 Compact全自动微生物分析系统进行鉴定及体外药物敏感性试验,聚合酶链反应(PCR)检测arm-A、rmt-A、rmt-B、rmt-C、rmt-D 5种16S r RNA甲基化酶基因和aac(3)-Ⅰ、aac(3)-Ⅱ、aac(6')-Ⅰb、aac(6')-Ⅱ、ant(3″)-Ⅰ、ant(2″)-Ⅰ6种氨基糖苷修饰酶基因。结果对氨基糖苷类药物耐药的铜绿假单胞菌同时对多种其他抗菌药物耐药,仅碳青霉烯类的亚胺培南耐药率较低,为5.7%。21株检出rmt-B 16S r RNA甲基化酶基因,占60.0%;30株检出氨基糖苷修饰酶基因,占85.7%,其中28株检出aac(3)-Ⅱ基因,占80.0%,18株检出ant(3″)-Ⅰ基因,占51.4%,其余8种基因未检出。结论在铜绿假单胞菌对氨基糖苷类抗菌药物耐药的菌株中,检测出rmt-B 16S r RNA甲基化酶基因和aac(3)-Ⅱ、ant(3″)-Ⅰ氨基糖苷修饰酶基因,铜绿假单胞菌多重耐药现象严重。     

产ESBLs大肠埃希菌对氨基糖苷类药物的耐药性及其耐药基因序列分析

目的研究云南玉溪市江川地区产超广谱β-内酰胺酶(ESBLs)大肠埃希菌对氨基糖苷类抗菌药物的耐药性及其耐药基因表达的频率,并对其耐药基因进行测序分析。方法采用纸片扩散法检测32株产ESBLs大肠埃希菌对庆大霉素、阿米卡星、卡那霉素、妥布霉素和奈替米星的耐药性。采用聚合酶链反应(PCR)检测7种氨基糖苷类修饰酶(AME)基因[aac(3)-Ⅰ、aac(3)-Ⅱ、aac(6′)-Ⅰad、aac(6′)-Ⅰb、aac(6′)-Ⅱ、ant(3″)-Ⅰ、ant(2″)-Ⅰ]和6种16S rRNA甲基化酶基因(armA、rmtA、rmtB、rmtC、rmtD、npmA),采用双脱氧末端终止法对aac(3)-Ⅱ基因进行测序分析。结果 32株产ESBLs大肠埃希菌对庆大霉素、阿米卡星、奈替米星、卡那霉素和妥布霉素的耐药率分别为100%、0%、0%、18%和87%。有6株菌株同时携带2种AME基因。从32株产ESBLs大肠埃希菌中检出aac(3)-Ⅱ、aac(6′)-Ⅰb、ant(3″)-Ⅰ、ant(2″)-Ⅰ4种AME基因,阳性率分别为100%、9.4%、6.2%和3.1%;未检出16S rRNA甲基化酶基因。32株产ESBLs大肠埃希菌中有4株发生相同的aac(3)-Ⅱ突变,分别为G232A、T251C、G580A和T612A。8株不产ESBLs大肠埃希菌均未检出AME基因及16S rRNA甲基化酶基因。结论云南玉溪市江川地区产ESBLs大肠埃希菌耐氨基糖苷类药物与AME基因表达有关,奈替米星的耐药率增加可能与aac(3)-Ⅱ基因突变有关。     

铜绿假单胞菌氨基糖苷类修饰酶基因探讨

目的了解浙江省丽水地区铜绿假单胞菌(PA)临床分离株中氨基糖苷类修饰酶(AMEs)基因存在状况。方法从分离的40株PA中,测定其对3种氨基糖苷类抗生素的敏感性,采用PCR及序列分析的方法分析AMEs基因{aac(3)-Ⅱ、aac(6′)-Ⅰ、aac(6′)-Ⅱ、ant(3″)-Ⅰ与ant(2″)-Ⅰ}类型。结果40株PA分离株中ant(2″)-Ⅰ和aac(6′)-Ⅱ基因阳性率分别为52.5%和45.0%,未检出aac(3)-Ⅱ、aac(6′)-Ⅰ、ant(3″)基因类型。结论浙江丽水地区耐氨基糖苷类抗生素的铜绿假单胞菌存在ant(2″)-Ⅰ和aac(6′)-Ⅱ基因,且PA对氨基糖苷类抗生素耐药严重,应注意对其进行临床监测和监控。     

多重耐药的铜绿假单胞菌Ⅰ类整合子与其多重耐药基因的相关性分析

目的 调查本院多重耐药铜绿假单胞菌耐药基因的存在状况,Ⅰ类整合子的分布情况以及其与多重耐药基因相关性分析.方法 采用K-B法测定临床分离的铜绿假单胞菌对15种药物的耐药性,筛选出35株多重耐药菌株,采用聚合酶链反应(PCR)检测β-内酰胺酶编码基因、OPrD2基因、氨基糖苷类修饰基因和Ⅰ类整合子基因.结果 35株多重耐药铜绿假单胞菌中β-内酰胺酶编码基因CTX-M-1、TEM、SHV的检出率分别为51.4%、31.4%、14.0%;OPrD2基因的阳性率为28.6%;氨基糖苷类修饰基因aac(6′)-Ⅱ、aac(6′)-Ⅰ、ant(3″)-Ⅰ和ant(3″)-Ⅱ的阳性率分别为20%、2.86%、14.3%和17.1%;Ⅰ类整合子阳性的菌株中,CTX-M-1、TEM、SHV、aac(6′)-Ⅱ和ant(3″)-Ⅰ的检出率为45.4%、9.1%、27.3%、36.4%和27.3%,未检出aac(6″)-Ⅰ和ant(2″)-Ⅰ基因.结论 本院多重耐药铜绿假单胞菌存在多种耐药基因,常见的有β-内酰胺酶编码基因、OPrD2基因和氨基糖苷类基因.Ⅰ类整合子广泛存在于多重耐药的铜绿假单胞菌中,并携带多种耐药基因参与形成铜绿假单胞菌的多重耐药.     

南京地区鲍曼不动杆菌氨基糖苷类药物修饰酶基因类型的调查

目的调查和研究南京地区鲍曼不动杆菌氨基糖苷类药物修饰酶基因类型及其耐药特性。方法用K-B法测定97株鲍曼不动杆菌对庆大霉素、阿米卡星2种抗菌药物的耐药性,用PCR法检测氨基糖苷类药物修饰酶基因。结果同时耐庆大霉素、阿米卡星的鲍曼不动杆菌44株,庆大霉素耐药阿米卡星敏感的有4株,庆大霉素敏感阿米卡星耐药的有3株,从51株表型耐药菌中检出4种修饰酶基因,其中带有aac(3)Ⅰ-基因19株(37.3%);带有aac(3)-Ⅱ基因15株(29.4%);有aac(6′)-Ⅰ基因8株(15.7%);ant(3″)Ⅰ-基因为3株(5.8%);同时具有aac(3)Ⅰ-和aac(6′)Ⅰ-基因的5株(9.8%);有aac(3)-Ⅱ和aac(6′)Ⅰ-基因的1株(1.9%)。结论南京地区鲍曼不动杆菌所带基因以aac(3)-Ⅰ和aac(3)-Ⅱ为主,其与氨基糖苷类药物耐药有一定的关系。     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.