Sample records for bla process cber

  1. CBERS-02 Application Assessment

    Institute of Scientific and Technical Information of China (English)

    GUO Jianning; YU Jin; MIN Xiangjun; LI Xingchao; HOU Minghui


    As the successor of CBERS-01, CBERS-02 was launched successfully on 21October 2003 and transmitted its first downlink data the next day. According to the OBT (On Board Test) outline, CRESDA cooperated with CAST and many remote sensing organizations in China in implementing the test of the satellite payloads, ground processing system and data application. In this paper, the test is briefly illustrated in three parts: Ⅰ. Satellite Parameters Test (especially the test for payloads), Ⅱ. Payload Image Quality Assessment, and Ⅲ. Data Application Assessment. The results of the test show that the image quality of CBERS-02 is much improved over CBERS-01 and will continue to play a more important role in the society and economic development of China.

  2. Center for Biologics Evaluation and Research (CBER) (United States)

    Federal Laboratory Consortium — CBER is the Center within FDA that regulates biological products for human use under applicable federal laws, including the Public Health Service Act and the Federal...

  3. CBERS-2B Monitored Forest Fires In Yunnan Province

    Institute of Scientific and Technical Information of China (English)



    @@ Several forest fires hit Yunnan Province,in the southwest of China from April 6 to 9.Two disastrous fires happened near Shangri-La County,Yunnan Province.According to the requirement of the Land and Surveying Department of Yunnan Province,the China Center for Resources Satellite Data & Application (CRESDA) provided satellite monitoring images to detect the events.The processed CBERS-2B images were delivered to the related departments for decision making and disaster relief.

  4. The Prototype Development for The Second Generation CBERS Initiates

    Institute of Scientific and Technical Information of China (English)



    It's reported that the concept for the second generation CBERS-CBERS-03 & 04 to be jointly developed by China Academy of Space Technology (CAST) and INPE went through the assessment by China Aerospace Science and Technology Corporation (CASC) at the beginning of the year. It means that the prototype development of CBERS-03 & 04 has been initiated.

  5. Applications Of CBERS Data In Oceanic Research

    Institute of Scientific and Technical Information of China (English)

    Li Xiaomin; Zhang Jie; Ma Yi; Song Pingjian


    @@ The CBERS series satellite data has been widely used by the First Institute of Oceanography, State Oceanic Administration (SOA) for the studies related to the monitoring of coral islands, land use changes of islands and coastal zone, green tide,implementation of ocean functional zoning, suspended particulate matter,sea ice, rafts cultivation and so on.The data covers the range of islands,coastal zone and inshore sea areas.

  6. The Application Achievements And Perspective Of CBERS Series Satellite Imagery

    Institute of Scientific and Technical Information of China (English)

    Li Xingchao; Qi Xueyong; Lu Yilin


    @@ Since the first China-Brazil Earth Resources Satellite (CBERS-1),launched in 1999,the CBERS data has been applied in many fields extensively.Remarkable social and economic benefits have been achieved.This article presents the application achievements during the past nine years,and gives a perspective for the future.All these applications demonstrate that the CBERS data has been an important data source for resources investigation and monitoring.

  7. Classification of CBERS-2 Imagery with Fuzzy ARTMAP Classifier%用模糊ARTMAP算法对中巴卫星02数据进行分类

    Institute of Scientific and Technical Information of China (English)

    骆成凤; 刘正军; 燕琴


    A fuzzy ARTMAP classifier is adopted for a classification experiment of CBERS-2 imagery. The fundamental theory and processing about the algorithm are first introduced, followed with a land-use classification experiment in Shihezi County on CBERS-2 high resolution imagery. Three classifiers are compared: maximum likelihood classifier (MLC), error back propagation (BP) classifier, and fuzzy ARTMAP classifier. The comparison shows comparably better results for the fuzzy ARTMAP classifier, with overall classification accuracy of 9.9% and 4.6% higher than that of MLC and BP. The results also prove that the fuzzy ARTMAP classifier has better discernment in identifying bare soil on CBERS-2 imagery.

  8. CBERS-2B Brazilian remote sensing satellite to help to monitor the Bolivia-Brazil gas pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Hernandes, Gilberto Luis Sanches [TBG Transportadora Brasileira Gasoduto Bolivia-Brasil, Rio de Janeiro, RJ (Brazil)


    This paper presents the results of CBERS-2B' Brazilian Remote Sensing Satellite to help to monitor the Bolivia-Brazil Gas Pipeline. The CBERS-2B is the third satellite launched in 2007 by the CBERS Program (China-Brazil Earth Resources Satellite) and the innovation was the HRC camera that produces high resolution images. It will be possible to obtain one complete coverage of the country every 130 days. In this study, 2 images from different parts of the Bolivia- Brazil Gas Pipeline were selected. Image processing involved the geometric registration of CBERS-2B satellite images with airborne images, contrast stretch transform and pseudo color. The analysis of satellite and airborne images in a GIS software to detect third party encroachment was effective to detect native vegetation removal, street construction, growth of urban areas, farming and residential/industrial land development. Very young, the CBERS-2B is a good promise to help to inspect the areas along the pipelines. (author)

  9. The investigation of special information distilling method of land use in karst area based on CBERS-02B and analysis on application: a case study of Duyun, Guizhou (United States)

    Hu, Juan; Luo, Miao; An, Yulun


    This paper explores the optimal methods for processing CBERS-02B images and using them to classify the land uses of karst mountain areas with 3S technologies, especially the RS digital image processing technology. Through multiple experiments and analysis, the difficulty of CBERS-02B images in distinguishing water from mountain shades, construction land from dry land and paddy field are satisfactorily removed. And the combination of band 421, based on OIF method, is proved optimal for classifying the land uses of karst areas. After comparing and evaluating the effect of HIS, PCA and HPC based image fusion methods, the HIS transformation based image fusion method is found best for CBERS-02B HR and CCD data fusion in the case of karst highland mountains. Based on the experiments, this paper proves that CBERS images are capable of large scale land use classification for karst areas, a competent substitute of TM images for karst mountain area land use survey.

  10. Atmospheric correction of CBERS CCD images with MODIS data

    Institute of Scientific and Technical Information of China (English)

    LI; Junsheng; ZHANG; Bing; CHEN; Zhengchao; SHEN; Qian


    China Brazil Earth Resource Satellite (CBERS) CCD images have much potential for inland water environmental monitoring. However, their atmospheric accuracy correction can affect their quantitative applications. This paper contains an atmospheric correction algorithm for CBERS CCD images with MODIS data from the same day, the use of which improves the atmospheric correction algorithm of ocean color remote sensing developed by Gordon (1993, 1994) and makes it applicable to inland waters. The improved algorithm retrieves atmospheric parameters from MODIS data and uses them to perform the atmospheric correction of CBERS CCD images. Experimental results show that the atmospheric correction algorithm of CBERS CCD images assisted by MODIS data is reliable. Furthermore, MODIS data can be freely obtained on a daily basis, making the algorithm developed in this paper useful for environmental monitoring of inland waters.

  11. Pre-Launch Absolute Calibration of CCD/CBERS-2B Sensor (United States)

    Ponzoni, Flávio Jorge; Albuquerque, Bráulio Fonseca Carneiro


    Pre-launch absolute calibration coefficients for the CCD/CBERS-2B sensor have been calculated from radiometric measurements performed in a satellite integration and test hall in the Chinese Academy of Space Technology (CAST) headquarters, located in Beijing, China. An illuminated integrating sphere was positioned in the test hall facilities to allow the CCD/CBERS-2B imagery of the entire sphere aperture. Calibration images were recorded and a relative calibration procedure adopted exclusively in Brazil was applied to equalize the detectors responses. Averages of digital numbers (DN) from these images were determined and correlated to their respective radiance levels in order to calculate the absolute calibration coefficients. It has been the first time these pre-launch absolute calibration coefficients have been calculated considering the Brazilian image processing criteria. Now it will be possible to compare them to those that will be calculated from vicarious calibration campaigns. This comparison will permit the CCD/CBERS-2B monitoring and the frequently data updating to the user community. PMID:27873886


    Directory of Open Access Journals (Sweden)

    E. Amraei


    Full Text Available CCD Camera is a multi-spectral sensor that is carried by CBERS 2 satellite. Imaging technique in this sensor is push broom. In images acquired by the CCD Camera, some vertical striping noise can be seen. This is due to the detectors mismatch, inter detector variability, improper calibration of detectors and low signal-to-noise ratio. These noises are more profound in images acquired from the homogeneous surfaces, which are processed at level 2. However, the existence of these noises render the interpretation of the data and extracting information from these images difficult. In this work, spatial moment matching method is proposed to modify these images. In this method, the statistical moments such as mean and standard deviation of columns in each band are used to balance the statistical specifications of the detector array to those of reference values. After the removal of the noise, some periodic diagonal stripes remain in the image where their removal by using the aforementioned method seems impossible. Therefore, to omit them, frequency domain Butterworth notch filter was applied. Finally to evaluate the results, the image statistical moments such as the mean and standard deviation were deployed. The study proves the effectiveness of the method in noise removal.


    Institute of Scientific and Technical Information of China (English)


    CRESDA Application System of CBERS-1 was established in 1999. During the operation of the system for more than two years, about 240 000 scenes of CBERS-1 Level 0 data have been archived and more than 13 000 scenes of Level 2 products have been ordered by end users from different application fields.In this paper, the typical examples of applications in crop yield estimation,calamity alleviation, resources survey and protection, environment monitoring and continuable development, and urban planning are mainly described.

  14. Discriminação de variedades de citros em imagens CCD/CBERS-2 Discrimination of citrus varieties using CCD/CBERS-2 satellite imagery

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    Ieda Del'Arco Sanches


    Full Text Available O presente trabalho teve o objetivo de avaliar as imagens CCD/CBERS-2 quanto à possibilidade de discriminarem variedades de citros. A área de estudo localiza-se em Itirapina (SP e, para este estudo, foram utilizadas imagens CCD de três datas (30/05/2004, 16/08/2004 e 11/09/2004. Um modelo que integra os elementos componentes da cena citrícola sensoriada é proposto com o objetivo de explicar a variabilidade das respostas das parcelas de citros em imagens orbitais do tipo CCD/CBERS-2. Foram feitas classificações pelos algoritmos Isoseg e Maxver e, de acordo com o índice kappa, concluiu-se que é possível obterem-se exatidões qualificadas como muito boas, sendo que as melhores classificações foram conseguidas com imagens da estação seca.This paper was aimed at evaluating the possibility of discriminating citrus varieties in CCD imageries from CBERS-2 satellite ("China-Brazil Earth Resouces Satellite". The study area is located in Itirapina, São Paulo State. For this study, three CCD images from 2004 were acquired (May 30, August 16, and September 11. In order to acquire a better understanding and for explaining the variability of the spectral behavior of the citrus areas in orbital images (like as the CCD/CBERS-2 images a model that integrates the elements of the citrus scene is proposed and discussed. The images were classified by Isoseg and MaxVer classifiers. According to kappa index, it was possible to obtain classifications qualified as 'very good'. The best results were obtained with the images from the dry season.

  15. Identifying Spatial Units of Human Occupation in the Brazilian Amazon Using Landsat and CBERS Multi-Resolution Imagery

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    Maria Isabel Sobral Escada


    Full Text Available Every spatial unit of human occupation is part of a network structuring an extensive process of urbanization in the Amazon territory. Multi-resolution remote sensing data were used to identify and map human presence and activities in the Sustainable Forest District of Cuiabá-Santarém highway (BR-163, west of Pará, Brazil. The limits of spatial units of human occupation were mapped based on digital classification of Landsat-TM5 (Thematic Mapper 5 image (30m spatial resolution. High-spatial-resolution CBERS-HRC (China-Brazil Earth Resources Satellite-High-Resolution Camera images (5 m merged with CBERS-CCD (Charge Coupled Device images (20 m were used to map spatial arrangements inside each populated unit, describing intra-urban characteristics. Fieldwork data validated and refined the classification maps that supported the categorization of the units. A total of 133 spatial units were individualized, comprising population centers as municipal seats, villages and communities, and units of human activities, such as sawmills, farmhouses, landing strips, etc. From the high-resolution analysis, 32 population centers were grouped in four categories, described according to their level of urbanization and spatial organization as: structured, recent, established and dependent on connectivity. This multi-resolution approach provided spatial information about the urbanization process and organization of the territory. It may be extended into other areas or be further used to devise a monitoring system, contributing to the discussion of public policy priorities for sustainable development in the Amazon.

  16. Land use mapping from CBERS-2 images with open source tools by applying different classification algorithms (United States)

    Sanhouse-García, Antonio J.; Rangel-Peraza, Jesús Gabriel; Bustos-Terrones, Yaneth; García-Ferrer, Alfonso; Mesas-Carrascosa, Francisco J.


    Land cover classification is often based on different characteristics between their classes, but with great homogeneity within each one of them. This cover is obtained through field work or by mean of processing satellite images. Field work involves high costs; therefore, digital image processing techniques have become an important alternative to perform this task. However, in some developing countries and particularly in Casacoima municipality in Venezuela, there is a lack of geographic information systems due to the lack of updated information and high costs in software license acquisition. This research proposes a low cost methodology to develop thematic mapping of local land use and types of coverage in areas with scarce resources. Thematic mapping was developed from CBERS-2 images and spatial information available on the network using open source tools. The supervised classification method per pixel and per region was applied using different classification algorithms and comparing them among themselves. Classification method per pixel was based on Maxver algorithms (maximum likelihood) and Euclidean distance (minimum distance), while per region classification was based on the Bhattacharya algorithm. Satisfactory results were obtained from per region classification, where overall reliability of 83.93% and kappa index of 0.81% were observed. Maxver algorithm showed a reliability value of 73.36% and kappa index 0.69%, while Euclidean distance obtained values of 67.17% and 0.61% for reliability and kappa index, respectively. It was demonstrated that the proposed methodology was very useful in cartographic processing and updating, which in turn serve as a support to develop management plans and land management. Hence, open source tools showed to be an economically viable alternative not only for forestry organizations, but for the general public, allowing them to develop projects in economically depressed and/or environmentally threatened areas.

  17. Performance evaluation of different classifiers (Isoseg, Bhattacharyya, Maxver e Maxver-ICM, using CCD/CBERS-1 and ETM+/Landsat-7 fused images

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    Wilson Lins de Mello Filho


    Full Text Available The aim of this study was to compare the performance of image classifiers (Isoseg, Bhattacharyya, Maxver and Maxver-ICM based on an accuracy analysis (set percentage, area determination and Kappa coefficient, using as ground truth an edited thematic map. For this, pre-processing techniques (atmospheric, geometric and radiometric corrections, contrast enhancement (IHS data fusion and principal component analysis and classification of CCD/CBERS-1 and ETM+/Landsat-7 images were done. Amongst all classifiers tested, Isoseg and Bhattacharyya presented best performance for the studied classes and the study area. It is anticipated that these results are relevant to environmental analyses based on orbital satellite data.

  18. Detection of blaIMP4 and blaNDM1 harboring Klebsiella pneumoniae isolates in a university hospital in Malaysia

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    Nurul Izzati Hamzan


    Full Text Available Background: Antibiotic resistance among Enterobacteriaceae posts a great challenge to the health care service. The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP is attracting significant attention due to its rapid and global dissemination. The infection is associated with significant morbidity and mortality, thus creating challenges for infection control and managing teams to curb the infection. In Southeast Asia, there have been limited reports and subsequent research regarding CRKP infections. Thus, the study was conducted to characterize CRKP that has been isolated in our setting. Methods: A total of 321 K. pneumoniae were included in the study. Each isolate went through an identification process using an automated identification system. Phenotypic characterization was determined using disk diffusion, modified Hodge test, Epsilometer test, and inhibitor combined disk test. Further detection of carbapenemase genes was carried out using polymerase chain reaction and confirmed by gene sequence analysis. Results: All together, 13 isolates (4.05% were CRKP and the majority of them were resistant to tested antibiotics except colistin and tigercycline. Among seven different carbapenemase genes studied (bla KPC, bla IMP, bla SME, bla NDM, bla IMI, bla VIM, and bla OXA, only two, bla IMP4 (1.87% and bla NDM1 (2.18%, were detected in our setting. Conclusion: Evidence suggests that the prevalence of CRKP in our setting is low, and knowledge of Carbapenem-resistant Enterobacteriaceae and CRKP has improved and become available among clinicians.

  19. Relation between blaTEM, blaSHV and blaCTX-M genes and acute urinary tract infections

    Institute of Scientific and Technical Information of China (English)

    Sima Sadat Seyedjavadi; Mehdi Goudarzi; Fattaneh Sabzehali


    Objective: To survey the frequency of blaTEM, blaSHV and blaCTX-M genotypes in extended-spectrum b-lactamase (ESBL)-producing Escherichia coli (E. coli) isolated from hospitalized patients with urinary tract infection and the determination of their antibiotic resistance patterns. Methods: During 11-month study, 100 ESBL-producing E. coli were collected from 330 patients who met the definition of urinary tract infection. The phenotypic identification of ESBL was confirmed by double disk synergy test and combined disk diffusion test. In vitro, susceptibility to ESBL isolates than 14 antimicrobial agents was performed by Kirby-Bauer disk diffusion method. The frequency of blaTEM, blaSHV and blaCTX-M ESBL-producing E. coli was assessed by PCR method. Results: The frequency of ESBL-producing E. coli was 40.8%. In vitro, susceptibility to ESBL-producing E. coli showed that the majority of isolates were highly susceptible to amikacin (74%) and imipenem (91%). The rates of resistance to other antibiotics varied from 33% to 96%. Through 100 tested isolates, the prevalence of blaTEM, blaSHV and blaCTX-M genes was determined to be 67%, 45% and 74% respectively. In comparison with other bla genes, the frequency of blaCTX-M was strikingly high. Conclusions: Due to the increase of E. coli with multiple ESBL genes, continuous sur-veillance in order to use appropriate antibiotics and the control of infections is necessary.

  20. Features information extraction of the mining area based on CBERS-02B%基于CBERS-02B的矿区地物信息的提取

    Institute of Scientific and Technical Information of China (English)

    王飞红; 任晓敏


    Object-oriented classification method is used to extract information from the Pingshuo surface coal mine in Shanxi Province. China-Brazil Earth Resources Satel ite(CBERS-02B)is used as data sources.The multi-scale segmentation and partitions level are created by object-oriented classification method.Through comparison of different segmentation results,the final segmentation scales are obtained.And spectral and spatial characteristics of the specific surface features are used to classify the image into vegetation, roads,mine construction,coal pile,mining face,waste rock dumps through the fuzzy classification of the membership function classification method.In the end,The classification result is evaluated by the error matrix,the result shows that the overal classification accuracy reaches 88.03%,and Kappa coefficient is 0.88.%应用面向对象分类方法,对山西省平朔露天煤矿进行信息提取。以中巴资源卫星CBERS-02B卫星遥感影像为数据源,利用面向对象分类方法进行多尺度分割并建立分割等级,通过对不同分割尺度的分割结果进行比较,获得最终分割尺度,并结合具体地物的光谱、空间等特征,采用模糊分类中的隶属度函数分类方法,最终将地物分为植被、道路、矿区建筑、煤堆、开采面、废石堆六类。最后使用误差矩阵对分类结果进行精度评价,其总体分类精度达到了88.63%,Kappa系数为0.89。

  1. Rapid discrimination of blaIMP-1, blaIMP-6, and blaIMP-34 using a multiplex PCR. (United States)

    Kayama, Shizuo; Ohge, Hiroki; Sugai, Motoyuki


    Stealth-type carbapenem-resistant Enterobacteriaceae that are resistant to almost all β-lactams except imipenem is emerging in Japan. This resistance is mediated by specific variants of the metallo-β-lactamases (blaIMP-6 or blaIMP-34) that differs by one amino acid from the common variant blaIMP-1. We developed an amplification refractory mutation system (ARMS) PCR assay enabling rapid, sequence independent, identification of these variants.

  2. Real-time PCR assays for the detection and quantification of carbapenemase genes (bla KPC, bla NDM, and bla OXA-48) in environmental samples. (United States)

    Subirats, Jèssica; Royo, Elena; Balcázar, José Luis; Borrego, Carles M


    In this study, we have developed real-time PCR assays using SYBR Green chemistry to detect all known alleles of bla KPC, bla NDM, and bla OXA-48-like carbapenemase genes in water, sediment, and biofilm samples collected from hospital and wastewater treatment plant (WWTP) effluents and rivers receiving chronic WWTP discharges. The amplification of bla KPC, bla NDM, and bla OXA-48 DNA was linear over 7 log dilutions (R (2) between 0.995 and 0.997) and showing efficiencies ranging from 92.6% to 100.3%. The analytical sensitivity indicated that the reaction for bla KPC, bla NDM, and bla OXA-48-like genes was able to detect 35, 16, and 19 copy numbers per assay, respectively. The three carbapenemase genes were detected in hospital effluents, whereas only the bla KPC and bla NDM genes were detected in biofilm and sediment samples collected from wastewater-impacted rivers. The detection of bla KPC, bla NDM, and bla OXA-48-like genes in different matrices suggests that carbapenem-resistant bacteria occur in both planktonic and benthic habitats thus expanding the range of resistance reservoirs for last-resort antibiotics. We believe that these real-time PCR assays would be a powerful tool for the rapid detection and quantification of bla KPC, bla NDM, and bla OXA-48-like genes in complex environmental samples.

  3. Energetic particle radiations measured by particle detector on board CBERS-1 satellite

    Institute of Scientific and Technical Information of China (English)

    HAO YongQiang; XIAO Zuo; ZOU Hong; ZHANG DongHe


    Using the data measured by energetic particle detector on board CBERS-01 and -02 for the past five years, statistics was made to show the general features of MeV electrons and protons along a solar synchronous orbit at an altitude of 780 km. This height is in the bottom region of the Earth's radiation belts. Detectors are inside the satellite cabinet and such continuous monitoring of particle radiation environment inside a satellite has seldom conducted so far. After a proper and careful treatment, it is indicated that the data inside satellite are well correlated with the radiation environment outside. Besides the agreement of the general distribution characteristics of energetic electrons and protons with similar observations from other satellites, attention is particularly paid to the disturbed conditions. Variations of particle fluxes are closely related with solar proton events, in general, electron fluxes of outer belt are well correlated with Dst index after three days' delay while the electron injection occurred almost at the same day during great magnetic storms. It is confirmed that both energetic electrons and protons appear in the Polar Cap region only after the solar proton events.

  4. Multiplex PCR amplification assay for the detection of blaSHV, blaTEM and blaCTX-M genes in Enterobacteriaceae. (United States)

    Monstein, H-J; Ostholm-Balkhed, A; Nilsson, M V; Nilsson, M; Dornbusch, K; Nilsson, L E


    Extended-spectrum beta-lactamases (ESBLs) are often mediated by (bla-)SHV, (bla)TEM and (bla)CTX-M genes in Enterobacteriaceae and other Gram-negative bacteria. Numerous molecular typing methods, including PCR-based assays, have been developed for their identification. To reduce the number of PCR amplifications needed we have developed a multiplex PCR assay which detects and discriminates between (bla-)SHV, (bla)TEM and (bla)CTX-M PCR amplicons of 747, 445 and 593 bp, respectively. This multiplex PCR assay allowed the identification of (bla-)SHV, (bla)TEM and (bla)CTX-M genes in a series of clinical isolates of Enterobacteriaceae with previously characterised ESBL phenotype. The presence of (bla)SHV, (bla)TEM and (bla)CTX-M genes was confirmed by partial DNA sequence analysis. Apparently, the universal well-established CTX-M primer pair used here to reveal plasmid-encoded (bla)CTX-M genes would also amplify the chromosomally located K-1 enzyme gene in all Klebsiella oxytoca strains included in the study.

  5. Detection of P. aeruginosa harboring bla CTX-M-2, bla GES-1 and bla GES-5, bla IMP-1 and bla SPM-1 causing infections in Brazilian tertiary-care hospital

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    Polotto Milena


    Full Text Available Abstract Background Nosocomial infections caused by Pseudomonas aeruginosa presenting resistance to beta-lactam drugs are one of the most challenging targets for antimicrobial therapy, leading to substantial increase in mortality rates in hospitals worldwide. In this context, P. aeruginosa harboring acquired mechanisms of resistance, such as production of metallo-beta-lactamase (MBLs and extended-spectrum beta-lactamases (ESBLs have the highest clinical impact. Hence, this study was designed to investigate the presence of genes codifying for MBLs and ESBLs among carbapenem resistant P. aeruginosa isolated in a Brazilian 720-bed teaching tertiary care hospital. Methods Fifty-six carbapenem-resistant P. aeruginosa strains were evaluated for the presence of MBL and ESBL genes. Strains presenting MBL and/or ESBL genes were submitted to pulsed-field gel electrophoresis for genetic similarity evaluation. Results Despite the carbapenem resistance, genes for MBLs (blaSPM-1 or blaIMP-1 were detected in only 26.7% of isolates. Genes encoding ESBLs were detected in 23.2% of isolates. The blaCTX-M-2 was the most prevalent ESBL gene (19.6%, followed by blaGES-1 and blaGES-5 detected in one isolate each. In all isolates presenting MBL phenotype by double-disc synergy test (DDST, the blaSPM-1 or blaIMP-1 genes were detected. In addition, blaIMP-1 was also detected in three isolates which did not display any MBL phenotype. These isolates also presented the blaCTX-M-2 gene. The co-existence of blaCTX-M-2 with blaIMP-1 is presently reported for the first time, as like as co-existence of blaGES-1 with blaIMP-1. Conclusions In this study MBLs production was not the major mechanism of resistance to carbapenems, suggesting the occurrence of multidrug efflux pumps, reduction in porin channels and production of other beta-lactamases. The detection of blaCTX-M-2,blaGES-1 and blaGES-5 reflects the recent emergence of ESBLs among antimicrobial resistant P. aeruginosa and

  6. The Frequency of blaVIM, blaIMP, blaKPC and blaNDM Carbapenemase Genes in Clinical Isolates of Klebsiella Pneumoniae in Kermanshah Medical Centers

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    A Zare


    Full Text Available Background: Carbapenemase genes have been spread among strains of Klebsiella pneumoniae that make them resistant to carbapenems. Hence, the present study aimed to study the prevalence of carbapenmase genes within K. pneumoniae isolates in Kermanshah medical centers. Methods: Sixty isolates of K. pneumoniae were collected and identified using API kit. Then, antibiotic susceptibility of isolates was determined using a disk diffusion method. The carbapenems-resistant isolates were screened for carbapenemases production using the Modified Hodge Test (MHT. The carbapenemase genes of blaVIM, blaIMP, KPC and blaNDM were detected by PCR test . Results: Out of 60 isolates, 4 isolates were resistant to carbapenem antibiotics, but only one isolate was demonstrated to be positive for carbapenemases by MHT phenotypic testing. The gene of blaVIM was detected in three isolates by PCR, though other genes were not found in the isolates. Within the isolates, 6.67% and 100% were resistant to carbapenem and ampicillin, respectively. Conclusion: The study findings revealed that dissemination rate of carbapenemase genes was not reported to be high among isolates of K. pneumoniae in Kermanshah. Only blaVIM gene was probably more frequent than other tested genes. Since most isolates examined in this study were susceptible to carbapenem antibiotics, these antibiotics are still regarded as effective drugs against infections caused by K. pneumoniae.

  7. Identification of blaOXA-51, blaOXA-58, blaDIM-1 and blaVIM carbapenemase genes in hospital enterobacteriaceae isolates from Sierra Leone (United States)

    We describe the results of a molecular epidemiological survey of 15 carbapenemase-encoding genes from a recent collection of clinical isolates. The most salient findings revealed that (i) 60% of the isolates harbored multiple carbapenemase genes, (ii) the blaDIM-1 gene that has only been reported in...

  8. Co-occurrence of blaNDM-1 with blaOXA-23 or blaOXA-58 in clinical multidrug-resistant Acinetobacter baumannii isolates in Algeria. (United States)

    Ramoul, Abir; Loucif, Lotfi; Bakour, Sofiane; Amiri, Sabrina; Dekhil, Mazouz; Rolain, Jean-Marc


    The aim of this study was to characterise the mechanisms of carbapenem resistance in Acinetobacter baumannii strains isolated in an Algerian hospital. A total of 43 imipenem-resistant A. baumannii clinical isolates collected between 2010 and 2013 were identified using API 20NE and were confirmed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS). Antibiotic susceptibility testing was performed by the disk diffusion and Etest methods. Carbapenemase activity was detected using microbiological tests and PCR. Genetic transfer of the blaNDM-1 gene was performed by conjugation using sodium azide-resistant Escherichia coli J53 as recipient strain. Clonal relationships were studied by multilocus sequence typing (MLST) using partial sequences of the csuE and blaOXA-51 genes. All 43 A. baumannii isolates were resistant to imipenem with high minimum inhibitory concentrations (MICs) (>32μg/mL). The strains harboured blaOXA-23, blaNDM-1, blaOXA-58 and/or blaOXA-24 genes. Co-existence of blaNDM-1 and blaOXA-23 or blaOXA-58 was detected in two isolates and one isolate, respectively. NDM-1 plasmid transfer to E. coli J53 was successful only for one of the three strains harbouring both blaNDM-1 and blaOXA-23 or blaOXA-58. The phylogenetic tree obtained from concatenation of the partial sequences of csuE and blaOXA-51 showed that there was no genetic relationship between the isolates and the blaNDM-1 resistance gene. Here we report for the first time the co-occurrence of blaNDM-1 along with blaOXA-23 or blaOXA-58 in recent clinical isolates of A. baumannii from Northeast Algeria. These findings re-emphasise the dissemination and rapid spread of blaNDM-1 carbapenemase genes in multidrug-resistant clinical A. baumannii isolates in Algeria.

  9. Aeromonas spp. simultaneously harbouring bla(CTX-M-15), bla(SHV-12), bla(PER-1) and bla(FOX-2), in wild-growing Mediterranean mussel (Mytilus galloprovincialis) from Adriatic Sea, Croatia. (United States)

    Maravić, Ana; Skočibušić, Mirjana; Samanić, Ivica; Fredotović, Zeljana; Cvjetan, Svjetlana; Jutronić, Marinka; Puizina, Jasna


    Aeromonas species are becoming renowned as emerging pathogens by increasingly giving rise to a wide spectrum of food and waterborne infections in humans. Another worrisome feature of aeromonads is the growing frequency of antibiotic resistance as a consequence of their prominent diversity in terms of resistance determinants. This study aimed at determining the antimicrobial resistance pattern, prevalence and characterization of acquired β-lactamases, including extended-spectrum-β-lactamases (ESBLs) and AmpC cephalosporinases, as well as the presence of class 1 and 2 integrons, in Aeromonas isolates from wild-growing Mediterranean mussel (Mytilus galloprovincialis) of the eastern coast of Adriatic Sea, Croatia. Isolates were tested for susceptibility to 16 antibiotics and β-lactam/β-lactamase inhibitor combinations. Cephalosporin-resistant isolates were further screened by PCR for genes encoding AmpC (bla(FOX), bla(CMY), bla(MOX), bla(LAT), bla(BIL), bla(DHA), bla(ACC), bla(MIR), bla(ACT)), ESBLs (bla(TEM), bla(SHV), bla(CTX-M), bla(PER), bla(VEB), bla(GES/IBC), bla(OXA)) and integrases (intI1, intI2, intI3). Location of bla genes was characterized by plasmid DNA fingerprinting and Southern blot hybridization. Plasmids carrying ESBL genes were investigated for transferability by conjugation and PCR-based replicon typed. Out of 147 Aeromonas isolates recovered, 30 (20%) demonstrated multiple resistance profile, with co-resistance most frequently detected against penicillins, piperacillin/sulbactam and tetracycline. ESBL-encoding genes were detected in 21 (13 Aeromonas caviae and 8 Aeromonas hydrophila) isolates, with bla(CTX-M-15) gene identified in 19 and bla(SHV-12) in 12 isolates. Among them, 10 isolates simultaneously harboured bla(CTX-M-15) and bla(SHV-12), while 3 isolates additionally carried an AmpC β-lactamase bla(FOX-2) gene. bla(PER-1) gene was identified in a single isolate also harbouring the bla(CTX-M-15) gene. While bla(SHV-12) was chromosomally

  10. CCD CBERS and ASTER data in dasometric characterization of Pinus radiata D. Don (north-western Spain

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    Eva Sevillano-Marco


    Full Text Available A Chinese-Brazilian Earth Resources Satellite (CBERS and an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER scenes coupled with ancillary georeferenced data and field survey were employed to examine the potential of the remote sensing data in stand basal area, volume and aboveground biomass assessment over large areas of Pinus radiata D. Don plantations in Northwestern Spain. Statistical analysis proved that the near infrared band and the shade fraction image showed significant correlation coefficients with all stand variables considered. Predictive models were accordingly selected and utilized to undertake the spatial distribution of stand variables in radiata stands delimited by the National Forestry Map. The study reinforces the potentiality of remote sensing techniques in a cost-effective assessment of forest systems.

  11. Identificação de fragmentos de floresta nativa, por diferentes intérpretes, com a utilização de imagens landsat e cbers em lavras, MG Identification of small areas of semideciduous forest, by different analysts, in Lavras region, MG, using Landsat and Cbers sattelites images

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    Elizabeth Ferreira


    Full Text Available Neste trabalho, as imagens dos satélites Landsat 7 e Cbers 2 foram analisadas com o objetivo de identificar áreas com fragmentos de floresta semidecídua e de avaliar a exatidão da classificação feita por diferentes intérpretes e técnicas de interpretação. O estudo foi realizado em Lavras, MG, utilizando o SIG-SPRING, que possui recursos para realização da classificação digital e visual. Na comparação das diferentes classificações e avaliação da exatidão, foram empregadas as exatidões global, do consumidor, do produtor e o coeficiente Kappa. Pelos resultados, verificou-se que a exatidão global foi maior que 90% e o coeficiente Kappa variou de 50% a 77% nas comparações feitas por diferentes intérpretes, em imagens Landsat e Cbers. Os mapas de fragmentos de vegetação produzidos com base na classificação digital das imagens Cbers e Landsat apresentaram alta porcentagem de áreas comuns e os intérpretes produziram diferentes mapas, porém, aqueles gerados pela imagem Cbers apresentaram a melhor concordância entre as classificações.In this work two images from Landsat 7 and Cbers 2 were analyzed in order to identify small areas of semideciduous forest and to evaluate the classification accuracy made by three different analysts. The study was carried out in Lavras region, MG, using the SPRING GIS with the appropriate functions to jufil the digital classification and visual inspection. The comparisons between the classifications and accuracy assessment procedures employed the overall accuracy, the user's accuracy, the producer's accuracy and the Kappa coefficient. The results showed that the overall accuracy were higher than 90% and the Kappa coefficient ranged from 50% to 77% when the Landsat and Cbers images were compared by different analysts. The fragments vegetation maps made from digital classification of Cbers and Landsat satellites images presented high percentage of common areas and analysts made different maps

  12. Characterization of a novel Klebsiella pneumoniae sequence type 476 carrying both bla KPC-2 and bla IMP-4. (United States)

    Wang, Y; Cao, W; Zhu, X; Chen, Z; Li, L; Zhang, B; Wang, B; Tian, L; Wang, F; Liu, C; Sun, Z


    Carbapenemase-producing Klebsiella pneumoniae has recently spread rapidly throughout China. In this study, we characterized a carbapenem-resistant K. pneumoniae isolate that produced both KPC-2 and IMP-4 type carbapenemases. A clinical isolate of K. pneumoniae, resistant to both meropenem and imipenem, was recovered from a urine sample. Antibiotic susceptibility was determined using the broth microdilution method and Etest (bioMérieux, France). Pulsed-field gel electrophoresis and multilocus sequence typing (MLST) were used for gene type analysis. bla (KPC) and the encoding genes of ESBLs and plasmid-mediated AmpC enzymes were polymerase chain reaction (PCR) amplified and sequenced. Plasmids were analyzed by transformation, enzyme restriction and Southern blot. PCR analysis revealed that the isolate was simultaneously carrying bla (KPC-2), bla (IMP-4), bla (TEM-1), and bla (OKP-B) genes. MLST assigned the isolate to a novel sequence type, ST476. bla (KPC-2)-harbouring plasmids of the isolate and comparative strains had similar EcoRI and HindIII restriction maps, while IMP-4-harbouring plasmids had variable HindIII restriction maps. Coexistence of bla (KPC-2) and bla (IMP-4) was probably due to bla (IMP-4)-harbouring plasmid transmission into KPC-2-producing K. pneumoniae (ST476). The concomitant presence of these genes is alarming and poses both therapeutic and infection control problems.

  13. Investigation of signal transduction routes within the sensor/transducer protein BlaR1 of Staphylococcus aureus. (United States)

    Staude, Michael W; Frederick, Thomas E; Natarajan, Sivanandam V; Wilson, Brian D; Tanner, Carol E; Ruggiero, Steven T; Mobashery, Shahriar; Peng, Jeffrey W


    The transmembrane antibiotic sensor/signal transducer protein BlaR1 is part of a cohort of proteins that confer β-lactam antibiotic resistance in methicillin-resistant Staphylococcus aureus (MRSA) [Fisher, J. F., Meroueh, S. O., and Mobashery, S. (2005) Chem. Rev. 105, 395-424; Llarrull, L. I., Fisher, J. F., and Mobashery, S. (2009) Antimicrob. Agents Chemother. 53, 4051-4063; Llarrull, L. I., Toth, M., Champion, M. M., and Mobashery, S. (2011) J. Biol. Chem. 286, 38148-38158]. Specifically, BlaR1 regulates the inducible expression of β-lactamases that hydrolytically destroy β-lactam antibiotics. The resistance phenotype starts with β-lactam antibiotic acylation of the BlaR1 extracellular domain (BlaRS). The acylation activates the cytoplasmic protease domain through an obscure signal transduction mechanism. Here, we compare protein dynamics of apo versus antibiotic-acylated BlaRS using nuclear magnetic resonance. Our analyses reveal inter-residue interactions that relay acylation-induced perturbations within the antibiotic-binding site to the transmembrane helix regions near the membrane surface. These are the first insights into the process of signal transduction by BlaR1.

  14. Detection of bla KPC-2 in Proteus mirabilis in Brazil

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    Adriane Borges Cabral


    Full Text Available INTRODUCTION : Infections caused by Klebsiella pneumoniae carbapenemase (KPC-producing isolates pose a major worldwide public health problem today. METHODS : A carbapenem-resistant Proteus mirabilis clinical isolate was investigated for plasmid profiles and the occurrence of β-lactamase genes. RESULTS : The isolate exhibited resistance to ertapenem and imipenem and was susceptible to meropenem, polymyxin, and tigecycline. Five plasmids were identified in this isolate. DNA sequencing analysis revealed the presence of bla KPC-2 and bla TEM-1 genes. An additional PCR using plasmid DNA confirmed that bla KPC-2 was present in one of these plasmids. Conclusions: We report the detection of bla KPC-2 in P. mirabilis in Brazil for the first time. This finding highlights the continuous transfer of bla KPC between bacterial genera, which presents a serious challenge to the prevention of infection by multidrug-resistant bacteria.

  15. Coexistence of blaNDM-1 、blaKPC-2 、blaDHA-1 、blaTEM-1 and blaOXA-1 genes in a clinical ST11 Klebsiella pneumoniae isolate in chi-na%首例同时携带 blaNDM-1、blaKPC-2、blaDHA-1、blaTEM-1和 blaOXA-1基因的 ST11肺炎克雷伯菌临床株

    Institute of Scientific and Technical Information of China (English)

    油丽萍; 陈爱文; 秦萍; 徐茶; 赵辉; 吴春梅; 朱元祺


    Objective To explore the molecular mechanism of the clinical carbapenem-resistant Klebsiella pneumon-iae isolates.Methods The strains identification and antibiotic susceptibilities were performed by VITEK-2 compact system.The genes of AmpC,ESBLs,MBL and KPCβ-lactamases were screened by specific PCR.And genotypes were confirmed by DNA sequencing.PFGE and multilocus sequence typing (MLST)were performed.Results 5 Klebsiella pneumoniae isolates were resistant to all antibiotics tested.Genotyping(PFGE)clustered 5 K .pneumoniae isolates into a single clonal type and MLST assigned them to sequence type 11.The blaKPC-2 ,baTEM-1 ,blaCTXG 9 and rmtB genes were present in four isolates.And Molecular testing verified the presence of blaNDM-1 ,blaKPC-2 ,blaDHA-1 ,blaTEM-1 and blaOXA-1 genes in a Klebsiella pneumoniae isolate.Conclusion To our knowledge,this is first report of coexistence of blaNDM-1 , blaKPC-2 ,blaDHA-1 ,blaTEM-1 and blaOXA-1 genes in a clinical Klebsiella pneumonia isolate.It may herald the emergence of a new pattern of drug resistance.Surveillance of metallo-β-lactamases in enterobacteriaceae is urgently needed to control and prevent the spread of these isolates.%目的:探讨产碳青霉烯酶肺炎克雷伯菌的耐药机制,为医院感染控制提供依据。方法法国 VITEK-2 Compact 对细菌进行鉴定和药敏试验;改良 Hodge 试验初筛肺炎克雷伯菌是否产碳青霉烯酶;多重 PCR 对菌株进行β-内酰胺类耐药基因和16S rRNA 甲基化酶基因的检测,测序确认基因型;多位点序列分型和脉冲场凝胶电泳实验进行细菌的同源性分析。结果5株肺炎克雷伯菌多位点序列分型是 ST11型,其中4株都同时携带有 blaKPC-2、blaTEM-1、blaCTXG 9和16S rRNA 甲基化酶 rmtB 基因,另外1株(HD03)肺炎克雷伯菌同时携带 blaNDM-1、blaKPC-2、blaDHA-1、blaTEM-1和 blaOXA-1基因。脉冲场凝胶电泳显示,除了 HD04菌株多一条带外,其余带型5株菌完

  16. Análise de mapas de represas publicados na web usando imagens orbitais CCD/CBERS no estado de Minas Gerais Analysis of dams maps published on the web by using orbital CCD/CBERS images in Minas Gerais State, Brazil

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    Elizabeth Ferreira


    Full Text Available Neste trabalho, bancos de dados públicos e gratuitos disponíveis na World Wide Web (WEB foram utilizados para avaliar as áreas das superfícies dos espelhos d'água das represas de Furnas e do Funil, no Estado de Minas Gerais. O objetivo foi comparar as informações obtidas nos bancos da WEB com os valores das áreas calculadas a partir de imagens do sensor CCD a bordo dos satélites CBERS2 e CBERS2B. A área da represa de Furnas obtida a partir das imagens CCD/CBERS2B, ano 2008, foi de 1.138 km², mas nos bancos de dados consultados esta área estava entre 1.182 e 1.503 km². A represa do Funil, construída em 2003, com superfície de espelho d'água de 29,37 km² e uma ilha com área de 1,93 km² não aparecem nos bancos Atlas, Geominas, IGAM e IBGE. Os resultados mostraram algumas discrepâncias nos bancos de dados publicados na WEB, tais como diferenças em áreas e supressão ou extrapolação de limites do espelho d'água. Concluiu-se que, até o momento, os responsáveis por algumas publicações de bancos de dados no Estado de Minas Gerais não tiveram rigor suficiente com as atualizações. As imagens CCD/CBERS, que também são dados públicos disponíveis na WEB, mostraram ser produtos adequados para verificar, atualizar e melhorar as informações publicadas.In this work some public databases from the World Wide Web (WEB were used to find the area of the Furnas and Funil Dams in Minas Gerais State. The purpose of this work was to compare the WEB public databases values and the real values obtained from the CCD camera images on board CBERS2 and CBERS2B satellites. The Furnas Dam area obtained from CCD/ CBERS2B images, in 2008, was 1.138 km², but in the consulted databases this area ranged from 1.182 to 1.503 km². The dam of the Funil, built in 2003, with a water surface of 29.37 km² and an island with 1.93 km² area, did not appear in Atlas, Geominas, IGAM and IBGE databases. The results revealed some problems in the WEB public

  17. Assessing the Relative Ecological Importance and Deforestation Risks of Unprotected Areas in Western Brazil Using Landsat, CBERS and Quantum GIS (United States)

    Smith, A.; Sevilla, C.; Lanclos, A.; Carson, C.; Larson, J.; Sankaran, M.; Saad, M.


    In addition to understanding Brazilian policies and currently utilized methodologies, the measurement of the impacts of deforestation is essential for enhancing techniques to reduce deforestation in the future. Adverse impacts of deforestation include biodiversity loss, increased carbon dioxide emissions, and a reduced rate of evapotranspiration, all of which contribute directly or indirectly to global warming. With the continual growth in population in developing countries such as Brazil, increased demands are placed on infrastructural development and food production. As a result, forested areas are cleared for agricultural production. Recently, exploration for hydrocarbons in Western Brazil has also intensified as a means to stimulate the economy, as abundant oil and gas is believed to be found in these regions. Unfortunately, hydrocarbon-rich regions of Western Brazil are also home to thousands of species. Many of these regions are as of yet untapped but are at risk of ecological disruption as a result of impending human activity. This project utilized Landsat 5 TM to monitor deforestation in a subsection of the Brazilian states of Rondônia and Amazonas. A risk map identifying areas susceptible to future deforestation, based on factors such as proximity to roads, bodies of water, cities, and proposed hydrocarbon activities such as pipeline construction, was created. Areas at higher risk of clearance were recommended to be a target for enhanced monitoring and law enforcement. In addition, an importance map was created based on biodiversity and location of endangered species. This map was used to identify potential areas for future protection. A Chinese-Brazilian satellite, CBERS 2B CCD was also utilized for comparison. The NDVI model was additionally replicated in Quantum GIS, an open source software, so that local communities and policymakers could benefit without having to pay for expensive ArcGIS software. The capabilities of VIIRS were also investigated to

  18. Remote Sensing of the EnviSat and Cbers-2B satellites rotation around the centre of mass by photometry (United States)

    Koshkin, N.; Korobeynikova, E.; Shakun, L.; Strakhova, S.; Tang, Z. H.


    During 2013-2015 the photometric observations of the EnviSat satellite, which became space debris after the failure in April 2012 in low Earth orbit, were performed. The rotation pole position and slow change in sidereal rotation period were updated on the basis of analysis of specular glints observed in 222 light curves using reduction of synodic periods. Apparently, there are minor oscillations of the rotation pole near the normal to the orbital plane. The sense of the EnviSat's spinning is opposite to the sense of its orbital rotation. The sidereal period is best approximated by the second-order polynomial: Psid (sec) = 0.000021534 ·T2 + 0.04936003 · T + 121.18195 where T is measured in days from the beginning of 2013. This method being applied to another representative of space debris, namely the Cbers-2B satellite, has shown a similar result: there is not precise solution for the rotation pole either as it undergoes oscillations with various time scale from several hours to several months. In 2014, the spin axis made the 10 ° angle with the normal to the orbital plane while the sense of spinning is direct in this case, i.e. coincides with the sense of orbital rotation. The sidereal period is best approximated by the following expression: Psid (sec) = 0.000029543 ·T2 + 0.08094931 · T + 81.31775 where T is measured in days starting from March 10, 2014. This method allows of controlling slow changes in the spatial orientation of the rotation axis of the satellites in which specular reflection of light from flat faces of the surface is inherent.

  19. Imipenem-resistant Acinetobacter baumannii carrying the ISAba1-bla OXA-23, 51 and ISAba1-bla ADC-7 genes in Monteria, Colombia

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    Pedro Martínez


    Full Text Available The purpose of this study was to identify the genes coding for resistance to ceftazidime and imipenem and describe the molecular epidemiology of A. baumannii strains isolated from a clinical center in Colombia. Twenty isolates of imipenem-resistant A. baumannii from an equal number of patients with nosocomial infections were obtained. Primers were used to amplify genes bla IMP, bla VIM, bla OXA-23, bla OXA-24, bla OXA-58, bla OXA-51 and bla ADC-7. To detect insertion sequences ISAba1/bla OXA-23, ISAba1/bla OXA-51 and ISAba1/bla ADC-7, mapping by PCR using combinations of reverse primers ISAba1 and reverse primers of bla OXA-23, bla OXA-51 and bla ADC-7 were used. The amplification products were purified and cloned into PCR 2.1-TOPO vector and transformed into chemically competent Escherichia coli TOP10. These amplicons were then sequenced. PFGE was performed on DNA of A. baumannii isolates digested with ApaI. Results. The DNA profiles obtained included 9 clusters with, four 2-7 isolates per profile, and 5 single-isolate profiles. Of the 20 isolates resistant to imipenem, 15 carried bla OXA-23 gene, 4 contained ISAba1 upstream of bla OXA-51 gene, and 6 contained ISAba1 upstream of bla OXA-23 gene. Eighteen of these isolates carried the bla ADC-7 gene, with 9 of the isolates having ISAba1 located upstream of this gene. This is the first report of the ISAba1 /ADC-7 associated with OXAs genes in A. baumannii isolates from Colombia.

  20. Direct detection of mecA, blaSHV , blaCTX-M , blaTEM and blaOXA genes from positive blood culture bottles by multiplex-touchdown PCR assay. (United States)

    Wang, M-Y; Geng, J-L; Chen, Y-J; Song, Y; Sun, M; Liu, H-Z; Hu, C-J


    Methicillin-resistant staphylococci (MRS) and ESBL(Extended-Spectrum β-Lactamase)-producing bacteria are the most important resistant pathogens in sepsis. In this study, a new multiplex-touchdown PCR method (MT-PCR) was developed to detect rapidly and simultaneously the presence of mecA, blaSHV , blaCTX-M , blaTEM and blaOXA genes from positive blood culture bottles. The technique showed a sensitivity of 10(3 ) CFU ml(-1) for mecA detection and of 10(2)  CFU ml(-1) for other genes, and 100% specificity in the detection of all genes. All genes were detected in the spiked blood culture bottles artificially contaminated with reference strains. Three methicillin-resistant S. aureus (MRSA), two methicillin-resistant S. epidermidis (MRSE) and 32 ESBL-producing bacteria, were isolated from the clinical blood culture specimens in 48 h by standard microbiological procedures. The corresponding genes were detected directly in the three MRSA, two MRSE and 29 ESBL-producing bacteria from the clinical blood culture specimens in 4 h by MT-PCR assay. None of the blaSHV , blaCTX-M , blaTEM and blaOXA genes were detected in three other bottles with ESBL-producing bacteria because of other ESBL genotypes in the pathogens. Likewise, all bottles proven negative by culture remained negative by PCR. The proposed method was rapid, sensitive and specific, and was able to directly detect the genes of MRS and ESBL-producing bacteria from the blood culture bottles.

  1. Detection of blaSHV, blaTEM and blaCTX-M antibiotic resistance genes in randomly selected bacterial pathogens from the Steve Biko Academic Hospital. (United States)

    Ehlers, Marthie M; Veldsman, Chrisna; Makgotlho, Eddy P; Dove, Michael G; Hoosen, Anwar A; Kock, Marleen M


    Extended-spectrum beta-lactamases (ESBLs) are considered to be one of the most important antibiotic resistance mechanisms. This study reported the ESBL-producing genes in 53 randomly selected clinical bacterial isolates from the Steve Biko Academic Hospital. The presence of the bla(SHV), bla(TEM) and bla(CTX-M) genes was determined, and the overall prevalence of these genes detected in this study was 87% (46/53) in comparison with the literature; these results were higher when compared with 33% for Escherichia coli in Europe and 0.8% in Denmark for similar pathogens. These research findings indicated that it is crucial to routinely monitor the prevalence of these resistance genes.

  2. Detection of extended-spectrum β-lactamases (blaCTX-M-1 and blaTEM in Escherichia coli, Salmonella spp., and Klebsiella pneumoniae isolated from poultry in North Eastern India

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    H. Lalzampuia


    Full Text Available Aim: The present study was conducted to record the association of extended spectrum β-lactamases (ESBLs producing enteric bacteria with diarrhea of poultry birds in Mizoram, India. Materials and Methods: Fecal samples were collected from poultry birds with the history of diarrhea from different parts of Mizoram. Samples were processed for isolation and identification of Escherichia coli, Salmonella, and Klebsiella pneumoniae. All the isolates were subjected to antibiotic sensitivity assays. Phenotypically, ESBLs production ability was determined by double discs synergy test (DDST method. ESBLs producing isolates were subjected to polymerase chain reaction (PCR for detection of ESBLs genes. Plasmids were cured by acridine orange. Transfer of resistance from donor to recipient strains was done by in vitro horizontal method. Results: A total of 134 enteric bacteria was isolated, of which 102 (76.12%, 21 (15.67% and 11 (8.21% were E. coli, Salmonella spp. and K. pneumoniae, respectively. By DDST 7 (5.22% isolates (6 E. coli and 1 K. pneumoniae were ESBLs producer. PCR analysis confirmed 5 (3.73% (4 E. coli and 1 K. pneumoniae isolates harboured blaCTX-M-1 gene and/or blaTEM gene. All the isolates were carrying plasmids ranging between 0.9 kb and ~30 kb. Of the 4 isolates positive for blaCTX-M-1 and/or blaTEM, 2 (1.84% were confirmed for blaCTX-M-1 gene in their plasmid. No blaTEM gene was detected from plasmid. The resistance plasmid could not be transferred to the recipient by in vitro horizontal gene transfer method. Conclusion: ESBLs producing enteric bacteria are circulating in poultry in North Eastern Region of India. As poultry is one of the most common food animals in this region, these organisms may enter in human population through them.

  3. Detection of blaSPM-1, blaKPC, blaTEM and blaCTX-M genes in isolates of Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella spp. from cancer patients with healthcare-associated infections. (United States)

    Jácome, Paula Regina Luna de Araújo; Alves, Lílian Rodrigues; Jácome-Júnior, Agenor Tavares; Silva, Maria Jesuíta Bezerra da; Lima, Jailton Lobo da Costa; Araújo, Paulo Sérgio Ramos; Lopes, Ana Catarina S; Maciel, Maria Amélia Vieira


    Pseudomonas aeruginosa, Acinetobacter spp. and Klebsiella spp. are three of the pathogens most frequently involved in infections of cancer patients, and the production of β -lactamases is a major mechanism of resistance due to its wide diversity of existing enzymes. Therefore, the aim of the present study was to investigate the microbiological profile and data related to patients and infections, and to search for β -lactamase genes in bacterial isolates from hospitalized cancer patients in a hospital in Recife, Pernambuco, Brazil. A total of 169 isolates were recovered between 2012 and 2014, of which 58 were P. aeruginosa, 36 were Acinetobacter spp. and 75 were Klebsiella spp. A high percentage of carbapenem resistance was observed in P. aeruginosa and Acinetobacter spp. Among the carbapenem-resistant bacteria, the blaSPM-1 gene was detected in P. aeruginosa (35.5 %) and Acinetobacter spp. (3.8 %), while blaKPC was detected in P. aeruginosa (25.8 %) only. Among the third- and fourth-generation cephalosporin-resistant strains, in Klebsiella spp. we detected the genes blaTEM (30.6 %), blaCTX-M (58.3 %) and blaKPC (5.6 %), and in Acinetobacter spp. only blaTEM (25.9 %). This the first report of an Acinetobacter baumannii blaSPM-1 gene carrier that has been isolated in Brazil. The most frequent cancer types were bowel tumour [14.8 %; 95 % confidence interval (CI95 %) 9.8-21.1 %], breast cancer (13.6 %; CI95 % 8.8-19.7 %) and prostate cancer (11.2%; CI95 % 6.9-17.0 %). These results therefore provide knowledge of susceptibility profile and resistance mechanisms and thus can contribute to the strategic formulation of hospital infection control plans and the rational use of antimicrobials, reducing mortality from infection levels in cancer patients.

  4. First Report of bla(IMP-8) in Raoultella planticola. (United States)

    Tseng, Sung-Pin; Wang, Jann-Tay; Liang, Chih-Yuan; Lee, Pei-Shan; Chen, Yee-Chun; Lu, Po-Liang


    Two carbapenem-resistant Raoultella planticola clinical isolates were isolated from patients with pneumonia and Port-A catheter-related bacteremia, respectively, in Taiwan. These isolates remained susceptible to fluoroquinolone, aminoglycoside, and colistin. Though the two isolates had the same antibiogram, plasmidic carbapenemase blaIMP-8, class 1 integron cassette (dfrA12-orfF-aadA2), and qnrB2, they had different pulsed-field gel electrophoresis patterns, plasmid sizes, and outer membrane protein loss profiles. To our knowledge, this is the first report of blaIMP-8 found in R. planticola. Interestingly, blaIMP-8 is the most common carbapenemase found in Klebsiella pneumoniae in Taiwan. In the literature, carbapenemase genes in R. planticola in each country were also found in carbapenem-resistant Enterobacteriaceae in the same country.

  5. Coexistence of blaOXA-48 and Truncated blaNDM-1 on Different Plasmids in a Klebsiella pneumoniae Isolate in China (United States)

    Xie, Lianyan; Dou, Yi; Zhou, Kaixin; Chen, Yue; Han, Lizhong; Guo, Xiaokui; Sun, Jingyong


    Objectives: To describe the genetic environment, transferability, and antibiotic susceptibility of one clinical Klebsiella pneumoniae isolate harboring both blaOXA-48 and blaNDM-1 on different plasmids from a Chinese hospital. Methods: The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using Etest and PCR. The plasmids harboring blaOXA-48 and blaNDM-1 were analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis, and hybridization with specific probes. Plasmid DNA was sequenced using Pacbio RS II and annotated using RAST. Results: K. pneumoniae RJ119, carrying both blaOXA-48 and blaNDM-1, was resistant to almost all carbapenems, cephalosporins, fluoroquinolone, and aminoglycosides and belonged to ST307. blaOXA-48 was located on a 61,748-bp IncL/M conjugative plasmid, which displayed overall nucleotide identity (99%) to pKPN-E1-Nr.7. blaNDM-1 was located on a 335,317-bp conjugative plasmid, which was a fusion of a blaNDM-1-harboring InA/C plasmid pNDM-US (140,825 bp, 99% identity) and an IncFIB plasmid pKPN-c22 (178,563 bp, 99% identity). The transconjugant RJ119-1 harboring blaNDM-1 was susceptible to carbapenem, and there was an insertion of IS10 into the blaNDM-1 gene. Conclusion: This is the first report of the coexistence of blaOXA-48 and blaNDM-1 in one K. pneumoniae clinical isolate in China. OXA-48 in RJ119 contributed to the majority to its high resistance to carbapenems, whereas NDM-1 remained unexpressed, most likely due to the insertion of IS10. Our results provide new insight for the relationship between genetic diagnosis and clinical treatment. They also indicate that increased surveillance of blaOXA-48 is urgently needed in China. PMID:28210248

  6. Two Multiplex Real-Time PCR Assays to Detect and Differentiate Acinetobacter baumannii and Non- baumannii Acinetobacter spp. Carrying blaNDM, blaOXA-23-Like, blaOXA-40-Like, blaOXA-51-Like, and blaOXA-58-Like Genes. (United States)

    Yang, Qiu; Rui, Yongyu


    Nosocomial infections caused by Acinetobacter spp. resistant to carbapenems are increasingly reported worldwide. Carbapenem-resistant Acinetobacter (CRA) is becoming a serious concern with increasing patient morbidity, mortality, and lengths of hospital stay. Therefore, the rapid detection of CRA is essential for epidemiological surveillance. Polymerase chain reaction (PCR) has been extensively used for the rapid identification of most pathogens. In this study, we have developed two multiplex real-time PCR assays to detect and differentiate A. baumannii and non-A. baumannii Acinetobacter spp, and common carbapenemase genes, including blaNDM, blaOXA-23-like, blaOXA-40-like, blaOXA-51-like, and blaOXA-58-like. We demonstrate the potential utility of these assays for the direct detection of blaNDM-, blaOXA-23-like-, blaOXA-40-like-, blaOXA-51-like-, and blaOXA-58-like-positive CRA in clinical specimens. Primers were specifically designed, and two multiplex real-time PCR assays were developed: multiplex real-time PCR assay1 for the detection of Acinetobacter baumannii 16S-23S rRNA internal transcribed spacer sequence, the Acinetobacter recA gene, and class-B-metalloenzyme-encoding gene blaNDM; and multiplex real-time PCR assay2 to detect class-D-oxacillinase-encoding genes (blaOXA-23-like, blaOXA-40-like, blaOXA-51-like,and blaOXA-58-like). The assays were performed on an ABI Prism 7500 FAST Real-Time PCR System. CRA isolates were used to compare the assays with conventional PCR and sequencing. Known amounts of CRA cells were added to sputum and fecal specimens and used to test the multiplex real-time PCR assays. The results for target and nontarget amplification showed that the multiplex real-time PCR assays were specific, the limit of detection for each target was 10 copies per 20 μL reaction volume, the assays were linear over six log dilutions of the target genes (r2 > 0.99), and the Ct values of the coefficients of variation for intra- and interassay

  7. Characterization of a novel blaIMP gene, blaIMP-58, using whole genome sequencing in a Pseudomonas putida isolate detected in Denmark

    DEFF Research Database (Denmark)

    Holmgaard, Dennis Back; Hansen, Frank; Hasman, Henrik;


    A multidrug-resistant strain of Pseudomonas putida was isolated from the urine of a 65-year-old women hospitalized for serious clinical conditions. Using whole genome sequencing a novel blaIMP gene, blaIMP-58 was discovered and characterized....

  8. Co-Carriage of blaKPC-2 and blaNDM-1 in Clinical Isolates of Pseudomonas aeruginosa Associated with Hospital Infections from India.

    Directory of Open Access Journals (Sweden)

    Deepjyoti Paul

    Full Text Available Global spread of KPC poses to be a serious threat complicating treatment options in hospital settings. The present study investigates the genetic environment of blaKPC-2 among clinical isolates of Pseudomonas aeruginosa from a tertiary referral hospital of India. The study isolates were collected from different wards and clinics of Silchar Medical College and Hospital, India, from 2012-2013. The presence of blaKPC was confirmed by genotypic characterization followed by sequencing. Cloning of the blaKPC-2 gene was performed and the genetic environment of this gene was characterized as well. Transferability of the resistance gene was determined by transformation assay and Southern hybridization. Additionally, restriction mapping was also carried out. Two isolates of P. aeruginosa were found to harbor blaKPC-2, were resistant towards aminoglycosides, quinolone and β-lactam-β-lactamase inhibitor combination. In both the isolates, the resistance determinant was associated with class 1 integron and horizontally transferable. Both the isolates were co-harboring blaNDM-1. The first detection of this integron mediated blaKPC-2 coexisting with blaNDM-1 in P. aeruginosa from India is worrisome, and further investigation is required to track the gene cassette mediated blaKPC-2 in terms of infection control and to prevent the spread of this gene in hospitals as well as in the community.

  9. Identification and molecular characterization of Escherichia coli blaSHV genes in a Chinese teaching hospital. (United States)

    Zhu, Mei; Yang, Guangjian; Li, Ailing; Zong, Li; Dong, Zhaoguang; Lu, Junwan; Zhang, Kaibo; Cheng, Cong; Chang, Qingli; Wu, Xiuying; Ying, Jianchao; Li, Xianneng; Ding, Li; Zheng, Haixiao; Yu, Junping; Ying, Jun; Xu, Teng; Yi, Huiguang; Li, Peizhen; Li, Kewei; Wu, Songquan; Bao, Qiyu; Wang, Junrong


    Escherichia coli (E. coli) commonly reside in human intestine and most E. coli strains are harmless, but some serotypes cause serious food poisoning. This study identified and molecularly characterized blaSHV genes from 490 E. coli strains with multi-drug resistance in a hospital population. PCR and molecular cloning and southern blot were performed to assess functions and localizations of this resistant E. coli gene and the pulsed-field gel electrophoresis (PFGE) was utilized to demonstrate the clonal relatedness of the positive E. coli strains. The data showed that 4 of these 490 E. coli strains (4/499, 0.8%) carried blaSHV genes that included EC D2485 (blaSHV-5), EC D2487 (blaSHV-5), EC D2684 (blaSHV-11) and EC D2616 (blaSHV-195, a novel blaSHV). Analysis of blaSHV open-reading frame showed that blaSHV-5 had a high hydrolysis activity to the broad-spectrum penicillin (ampicillin or piperacillin), ceftazidime, ceftriaxone, cefotaxime and aztreonam. blaSHV-195 and blaSHV-11 had similar resistant characteristics with high hydrolysis activities to ampicillin and piperacillin, but low activities to cephalosporins. Moreover, the two blaSHV-5 genes were located on a transferable plasmid (23kb), whereas the other two blaSHV variants (blaSHV-11 and blaSHV-195) seemed to be located in the chromosomal material. Both EC D2485 and EC D2487 clones isolated in 2010 had the same DNA finger printing profile and they might be the siblings of clonal dissemination. The data from the current study suggest that the novel blaSHV and clonal dissemination may be developed, although blaSHV genes were infrequently identified in this hospital population. The results of the work demonstrate the necessity for molecular surveillance in tracking blaSHV-producing strains in large teaching hospital settings and emphasize the need for epidemiological monitoring.

  10. Increasing secondary bacterial infections with Enterobacteriaceae harboring blaCTX-M-15 and blaCMY-6 in patients with bronchogenic carcinoma:an emerging point of concern

    Institute of Scientific and Technical Information of China (English)

    Mohammed Shahid; Abida Malik; Rakesh Bhargava


    Objective: To look for secondary bacterial infections in bronchogenic carcinoma (BCA) with resistant organisms harboring bla genes considering the paucity of relevant studies. Methods:A total of 137 confirmed cases of BCA and 34 healthy volunteers were studied for the occurrence and prevalence of blaCTX-M and and blaAmpC harboring-enterobacteriaceae. A subset of these patients (n=69) was previously reported for the secondary infection with the Aspergillus species. Bronchoalveolar lavages (BAL) were subjected for bacterial and fungal cultures and the bacterial isolates were screened by multiplex PCRs for the presence of blaCTX-M and blaAmpC. The isolates were also screened for the association of insertion sequence (IS26) by PCR and characterized by RAPD for any clonal relatedness. Results: A total of 143 bacterial isolates were obtained from 137 BAL specimens of BCA patients. The Enterobacteriaceae-isolates were multidrug-resistant showing concomitant resistance to fluoroquinolones and aminoglycosides. Both blaCTX-M and blaAmpC of CIT family were detected in 77.4% and 27.4% isolates, respectively. Sequencing revealed the presence of blaCTX-M-15 and blaCMY-6. Twenty one percent of the isolates were simultaneously harboring blaampC and blaCTX-M-15. IS26 PCR and RAPD typing revealed the presence of diverse bacterial population but no predominant clone was identified. The present study also suggests strong association of aspergillosis with lung cancer and further strengthens the potential use of non-validated serological tests suggested earlier. Conclusions: We emphasize that all patients of bronchogenic carcinoma should also be screened for secondary bacterial infections, along with secondary fungal infections, so as to introduce early and specific antimicrobial therapy and to prevent unwanted deaths.

  11. Outbreak Caused by blaOXA-72-Producing Acinetobacter baumannii ST417 Detected in Clinical and Environmental Isolates. (United States)

    Tamayo-Legorreta, Elsa; Turrubiartes-Martínez, Edgar; Garza-Ramos, Ulises; Niño-Moreno, Perla; Barrios, Humberto; Sánchez-Pérez, Alejandro; Reyna-Flores, Fernando; Tovar-Oviedo, Juana; Magaña-Aquino, Martin; Cevallos, Miguel Angel; Silva-Sanchez, Jesus


    We characterized an outbreak of imipenem-resistant Acinetobacter baumannii with clinical and environmental isolates from a tertiary care hospital in San Luis Potosi, Mexico. During a 4-month period, a total of 32 nonrepetitive imipenem-resistant clinical isolates of A. baumannii were collected. All isolates were susceptible to colistin and tigecycline and resistant to cefepime, ceftazidime, ceftriaxone, imipenem, and meropenem. Genotyping by pulsed-field gel electrophoresis showed a major clone (A). Multilocus sequence type (MLST) analysis was performed, revealing sequence type (ST) 417 (ST417) and 208 (ST208). The blaIMP-, blaVIM-, blaGIM-, blaSIM-, blaNDM-type, and blaOXA-type (blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, and blaOXA-58-like) genes were screened and showed that the blaOXA-51-like and blaOXA-24-like genes were present in all isolates. Sequencing and southern hybridization were performed, confirming the presence of the blaOXA-72 gene and its plasmid-borne nature. In addition, the blaOXA-72-XerC/XerD-like association was identified. These findings indicate that a clonal spread of blaOXA-72-producing A. baumannii ST417 had occurred throughout the hospital. The ST417 corresponded with a previous ST described in the United States.

  12. 75 FR 54343 - Center for Biologics Evaluation and Research eSubmitter Pilot Evaluation Program for Blood... (United States)


    ...The Food and Drug Administration (FDA), Center for Biologics Evaluation and Research (CBER) is announcing an invitation to participate in a pilot evaluation program for CBER's eSubmitter Program (eSubmitter). CBER's eSubmitter has been customized as an automated biologics license application (BLA) and BLA supplement (BLS) submission system for blood and blood components. Participation in the......

  13. Drug resistance of Acinetobacter baumannii and detection of blaOXA gene%鲍氏不动杆菌耐药性及blaOXA基因检测

    Institute of Scientific and Technical Information of China (English)

    张玉英; 赵志军; 师志云; 李刚; 贾伟


    目的:了解鲍氏不动杆菌(ABA)的耐药特点及blaOXA基因类型,为临床合理使用抗菌药物、有效控制医院感染的发生提供科学依据。方法收集医院自2006年1月-2009年12月临床感染标本分离的鲍氏不动杆菌309株采用K-B法进行药敏试验;利用PCR技术检测 blaOX A-23、blaOX A-24、blaOX A-51和 blaOX A-58基因。结果309株ABA对亚胺培南、美罗培南的耐药率最低,分别为19.7%、20.4%,其次是米诺环素29.5%,阿米卡星39.9%,对其余17种抗菌药物的耐药率均在>45.0%;blaOX A-23基因阳性46株,占14.9%,OX A-51基因阳性302株,占97.7%,未检测到blaOX A-24、blaOX A-58基因型。结论鲍氏不动杆菌耐药情况严重,blaOX A-23型碳青酶烯酶基因的产生是鲍氏不动杆菌耐药的重要机制之一。%OBJECTIVE To investigate the characteristics of drug resistance of Acinetobacter baumannii and observe the blaOXA genotypes so as to provide scientific bases for reasonable clinical use of antibiotics and effective control of nosocomial infections .METHODS From Jan 2006 to Dec 2009 ,totally 309 strains of A .baumannii isolated from infectious specimens were collected ,then the drug susceptibility testing was performed with the use of K-B meth-od ,and the PCR technique was employed to detect the blaOXA-23 ,blaOXA-24 ,blaOXA-51 ,and blaOXA-58 gene .RESULTS The drug resistance rate of the 309 strains of A .baumannii to imipenem was 19 .7% ,meropenem 20 .4% ,minocycline 29 .5% ,amikacin 39 .9% ;the drug resistance rates to other 17 antibiotics were more than 45 .0% .There were 46 (14 .9% ) strains with blaOXA-23 tested positive and 302 (97 .7% ) strains with blaOXA-51 tested positive ,while the genotypes of blaOXA-24 and blaOXA-58 have not been detected .CONCLUSION The A .baumannii strains are highly drug resistant ,and the production of carbapenemase gene blaOXA-23 is one of the important mechanisms of resistance

  14. Investigation of diversity of plasmids carrying the blaTEM-52 gene

    DEFF Research Database (Denmark)

    Bielak, Eliza Maria; Bergenholtz, Rikke D.; Jørgensen, Mikael Skaanning;


    OBJECTIVES: To investigate the diversity of plasmids that carry blaTEM-52 genes among Escherichia coli and Salmonella enterica originating from animals, meat products and humans. METHODS: A collection of 22 blaTEM-52-encoding plasmids was characterized by restriction fragment length polymorphism...... of self-transfer to a plasmid-free E. coli recipient. CONCLUSIONS: The blaTEM-52 gene found in humans could have been transmitted on transferable plasmids originating from animal sources. Some of the blaTEM-52 plasmids carry replicons that differ from the classical ones. Two novel replicons were detected...

  15. blaCTX-M,blaTEM, andblaSHV inEnterobacteriaceae from North-Indian tertiary hospital:high occurrence of combination genes

    Institute of Scientific and Technical Information of China (English)

    Mohammed Shahid; Anuradha Singh; Farrukh Sobia; Mohammad Rashid; Abida Malik; Indu Shukla; Haris Manzoor Khan


    Objective:To delineate the frequency of occurrence ofblaCTX-M,blaTEM, andblaSHV in Enterobacteriaceae from North-Indian tertiary hospital.Methods: A random collection of a subset of45Escherichia coli (E. coli) and28Klebsiella pneumoniae (K. pneumoniae) that was resistant to a third generation cephalosporin and obtained during2007-2008 was selected for detailed screening forblaCTX-M,blaTEM, andblaSHV by monoplexPCRs. The isolates demonstrating the presence of blaCTX-M alleles were characterized for the specificCTX-M-genogroup by using a multiplexPCR.Results:Resistance to cefoperazone, ceftazidime, ceftriaxone, cefotaxime, cefoxitin and piperacillin was 100% each inK. pneumoniae isolates, whereas these resistance-rates forE. coli isolates were93.1%, 83.8%, 91.9%, 93.6%, 97.3% and97.1%, respectively. Concomitant resistance to aminoglycosides, quinolones and aztreonam was also noticed. Presence of any of the bla genes (blaCTX-M,blaTEM, andblaSHV) was noticed in a total of28 (38.4%) isolates of the73isolates studied. Many isolates demonstrated occurrence of these genes in various combinations.blaCTX-M,blaTEM, andblaSHV were noticed in 28.8%,10.9% and13.7% isolates, respectively. MultiplexPCR inblaCTX-Mharboring isolates demonstrated the presence ofCTX-M-Genogroup-1 and sequencing for the specificCTX-M-type revealed presence ofCTX-M-15 type. RAPD typing showed wide diversity in isolates.Conclusions:This is amongst the premier report describing the simultaneous occurrence ofblaTEM,blaSHV, andblaampC in IndianEnterobacteriaceae and that wider dissemination of these genes, as demonstrated by diversity of isolates, raises concern and emphasizes a need for extensive search for the presence of these gene pools in Indian subcontinent.

  16. Complete sequencing of an IncX3 plasmid carrying blaNDM-5 allele reveals an early stage in the dissemination of the blaNDM gene

    Directory of Open Access Journals (Sweden)

    M Krishnaraju


    Full Text Available Purpose: The aim of the present study was to perform molecular characterisation of the blaNDM plasmids and to understand the mechanism of its spread among pathogenic bacteria. Materials and Methods: Seventy-six non-repetitive carbapenem-resistant isolates which were collected during Nov 2011 to April 2013 from four hospitals in Chennai were analyzed for the presence of the blaNDM gene by PCR. Further, the genetic context of the blaNDM gene was analyzed by PCR specific to ISAba125 and bleMBL gene. One of the blaNDM plasmid was completely sequenced in the Illumina HiSeq platform. Results: Twenty-three isolates consisting of 8 Escherichia coli, 8 Klebsiella pneumoniae, 3 Klebsiella oxytoca, 3 Acinetobacter baumanii and 1 Pseudomonas aeruginosa were found to carry the blaNDM gene. In 18 isolates the blaNDM gene was associated with a bleMBL gene and the ISAba125 element. The complete sequencing of pNDM-MGR194 revealed an IncX3 replication type plasmid, with a length of 46,253 bp, an average GC content of 47% and 59 putative ORFs. The iteron region contained the blaNDM5 gene and the bleMBL , trpF and dsbC genes downstream and an IS5 inserted within the ISAba125 element upstream. Conclusion: This is the first report where the blaNDM gene insertion in a plasmid is not accompanied by other resistance gene determinants. These observations suggest that the IncX3 plasmid pNDM-MGR194 is an early stage in the dissemination of the blaNDM .

  17. High prevalence of multidrug-resistance in Acinetobacter baumannii and dissemination of carbapenemase-encoding genes blaOXA-23-like, blaOXA-24-like and blaNDM-1 in Algiers hospitals

    Institute of Scientific and Technical Information of China (English)

    Khadidja Khorsi; Yamina Messai; Moufida Hamidi; Houria Ammari; Rabah Bakour


    Objective:To assess and characterize antibiotic resistance in Acinetobacter baumannii strains recovered from 5 health-care facilities in Algiers. Methods:Antibiotic susceptibility testing was performed by agar diffusion and agar dilution methods, resistance genes were identified by PCR and sequencing, and molecular typing of isolates was carried out by enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR). Results:Among 125 tested isolates, 117 (93.6%) were multidrug-resistant, of which 94 (75.2%) were imipenem resistant. The blaADC and blaOXA-51-like genes were detected in all isolates, in association with ISAba1 sequence in 84%and 8%(imipenem resistant) of isolates, respectively. The blaOXA-23-like and blaOXA-24-like carbapenemase genes were detected in 67.02%and 20.21%of imipenem-resistant isolates, respectively. The blaOXA-23-like gene is linked to ISAba1 or ISAba4 elements. The metallo-β-lactamase NDM-1 gene was found in 10 (10.6%) imipenem-resistant strains from three hospitals, it is linked to ISAba125 element in nine strains. Extended spectrumβ-lactamases production was not detected. Imipenem and cefotaxime resistance phenotypes could not be transferred to Escherichia coli by conjugation. Outer membrane protein CarO gene was not detected in four imipenem-resistant isolates. The aac(6’)-Ib, sul1, sul2, tetA and tetB genes were present in 5.31%, 36.17%, 77.65%, 1.06%and 65.92%of strains, respectively. Class 1 integrons were detected in 23.4%strains. ERIC-PCR typing showed a genetic diversity among blaOXA-23-like and blaOXA-24-like positive strains, while clonality was observed among blaNDM-1 positives. Conclusions:This study highlighted the high prevalence of imipenem resistance in Acinetobacter baumannii in Algiers hospitals mediated mainly by blaOXA-23-like, blaOXA-24-like, and blaNDM-1 genes.

  18. Klebsiella pneumoniae Isolate from a New York City Hospital Belonging to Sequence Type 258 and Carrying blaKPC-2 and blaVIM-4. (United States)

    Castanheira, Mariana; Deshpande, Lalitagauri M; Mills, Janet C; Jones, Ronald N; Soave, Rosemary; Jenkins, Stephen G; Schuetz, Audrey N


    Among 69 of 139 (49.6%) carbapenem-nonsusceptible Enterobacteriaceae carrying blaKPC, 1 Klebsiella pneumoniae was also positive for blaVIM. The isolate belonged to sequence type 258 (ST258) and carried blaKPC-2 on a copy of Tn4401a and blaVIM-4 on a class 1 integron. Genes were located on distinct plasmids belonging to Inc types A/C and FII. Elevated expression of the efflux pump AcrAB-TolC (acrA, 15.3 times) and reduced expression of outer membrane protein genes ompK35 and ompK37 (0.16 and 0.081 times, respectively) associated with various amino acid alterations on OmpK37 were observed. The presence of two carbapenemases in ST258 K. pneumoniae is of great concern due to the ability of this organism to widely disseminate.

  19. Evolution of IncA/C blaCMY-₂-carrying plasmids by acquisition of the blaNDM-₁ carbapenemase gene. (United States)

    Carattoli, Alessandra; Villa, Laura; Poirel, Laurent; Bonnin, Rémy A; Nordmann, Patrice


    The bla(NDM-1) gene has been reported to be often located on broad-host-range plasmids of the IncA/C type in clinical but also environmental bacteria recovered from the New Delhi, India, area. IncA/C-type plasmids are the main vehicles for the spread of the cephalosporinase gene bla(CMY-2), frequently identified in the United States, Canada, and Europe. In this study, we completed the sequence of IncA/C plasmid pNDM-KN carrying the bla(NDM-1) gene, recovered from a Klebsiella pneumoniae isolate from Kenya. This sequence was compared with those of three IncA/C-type reference plasmids from Escherichia coli, Yersinia ruckeri, and Photobacterium damselae. Comparative analysis showed that the bla(NDM-1) gene was located on a widely diffused plasmid scaffold known to be responsible for the spread of bla(CMY-2)-like genes and consequently for resistance to broad-spectrum cephalosporins. Considering that IncA/C plasmids possess a broad host range, this scaffold might support a large-scale diffusion of the bla(NDM-1) gene among Gram-negative rods.

  20. β-Lactam Resistance Genes: Characterization, Epidemiology, and First Detection of blaCTX-M-1 and blaCTX-M-14 in Salmonella spp. Isolated from Poultry in Brazil-Brazil Ministry of Agriculture's Pathogen Reduction Program. (United States)

    Fitch, Fernanda Marques; Carmo-Rodrigues, Mirian Silva; Oliveira, Vinicius Gomes Sales; Gaspari, Marcus Vinicius; Dos Santos, Amaury; de Freitas, Josinete Barros; Pignatari, Antonio C C


    Salmonella spp. are widespread in nature; however, human infections occur mainly through ingestion of contaminated food, specially poultry and eggs. In Brazil, the Ministry of Agriculture (MAPA) oversees food production in general, with the goal of preventing transmission of pathogens through the food chain. In 2004, MAPA initiated a program to monitor and control levels of Salmonella in poultry during slaughter. This study analyzes isolates from MAPA's program for β-lactam resistance and the resistance genes involved, as well as the geographic distributions of potentially clonal populations of resistant isolates within Brazil. Initially, 1,939 Salmonella spp. isolated between 2004 and 2011 were examined. These isolates were tested for antimicrobial susceptibility, and 100 isolates resistant or intermediate to ampicillin and ceftriaxone were screened initially for the presence of blaSHV, blaTEM, blaOXA, blaPSA, blaCMY-1, and blaCMY-2 genes. There were 55 isolates whose resistance genes were not identified by this panel and these isolates are the subject of this report. These 55 isolates were differentiated into 31 distinct ribogroups, with multiple β-lactam resistance genes, including AmpC blaCMY, blaTEM, blaCTX-M-1, blaCTX-M-2, blaCTX-M-8, and blaCTX-M-14. Isolates carrying variants of blaCTX-M were identified in three geographic regions. Salmonella carrying particular genetic variants of blaCTX-M and belonging to the same ribogroup were identified from multiple poultry slaughtering facilities. In some instances, these presumptive clonal-related isolates were from facilities over 300 miles apart, indicating potential clonal spread between two geographic regions. This is the first report of blaCTX-M-1 and blaCTX-M-14 in Salmonella in Brazil.

  1. Yersinia enterocolitica and Photorhabdus asymbiotica β-lactamases BlaA are exported by the twin-arginine translocation pathway. (United States)

    Schriefer, Eva-Maria; Hoffmann-Thoms, Stephanie; Schmid, Franz X; Schmid, Annika; Heesemann, Jürgen


    In general, β-lactamases of medically important Gram-negative bacteria are Sec-dependently translocated into the periplasm. In contrast, β-lactamases of Mycobacteria spp. (BlaC, BlaS) and the Gram-negative environmental bacteria Stenotrophomonas maltophilia (L2) and Xanthomonas campestris (Bla(XCC-1)) have been reported to be secreted by the twin-arginine translocation (Tat) system. Yersinia enterocolitica carries 2 distinct β-lactamase genes (blaA and blaB) encoding BlaA(Ye) and the AmpC-like β-lactamase BlaB, respectively. By using the software PRED-TAT for prediction and discrimination of Sec from Tat signal peptides, we identified a functional Tat signal sequence for Yersinia BlaA(Ye). The Tat-dependent translocation of BlaA(Ye) could be clearly demonstrated by using a Y. enterocolitica tatC-mutant and cell fractionation. Moreover, we could demonstrate a unique unusual temperature-dependent activity profile of BlaA(Ye) ranging from 15 to 60 °C and a high 'melting temperature' (T(M)=44.3°) in comparison to the related Sec-dependent β-lactamase TEM-1 (20-50°C, T(M)=34.9 °C). Strikingly, the blaA gene of Y. enterocolitica is present in diverse environmental Yersinia spp. and a blaA homolog gene could be identified in the closely related Photorhabdus asymbiotica (BlaA(Pa); 69% identity to BlaA(Ye)). For BlaA(Pa) of P. asymbiotica, we could also demonstrate Tat-dependent secretion. These results suggest that Yersinia BlaA-related β-lactamases may be the prototype of a large Tat-dependent β-lactamase family, which originated from environmental bacteria.

  2. Molecular detection of metallo-β-lactamase genes, blaIMP-1, blaVIM-2 and blaSPM-1 in imipenem resistant Pseudomonas aeruginosa isolated from clinical specimens in teaching hospitals of Ahvaz, Iran

    Directory of Open Access Journals (Sweden)

    Mojtaba Moosavian


    Full Text Available Background and Objectives: Carbapenem resistant Pseudomonas aeruginosa is a serious cause of nosocomial infections.The main purpose of the study is to determine the prevalence rate of imipenem resistant Pseudomonas aeruginosa carryingmetallo- beta- lactamase (MBL genes.Material and Methods: 236 Pseudomonas aeruginosa isolates were collected from teaching hospitals of Ahvaz Universityof Medical Sciences during a period of 9 months in 2012. These strains were identified using conventional microbiologicaltests. The susceptibility of isolates to antibiotics were assessed using disk diffusion test. The IMP-EDTA combination diskphenotypic test was performed for detection of MBL producing strains. Finally, polymerase chain reaction (PCR wasperformed to detect MBL genes, blaIMP-1, blaVIM-2 and blaSPM-1 in imipenem resistant strains.Results: Out of 236 examined isolates, 122 isolates (51.4% were resistant to imipenem. The IMP-EDTA combination testshowed that among 122 imipenem resistant strains, 110 strains (90% were phenotipically MBL producers. Additionally, theresults of PCR method showed that 2 strains (1.6% and 67strains (55% of imipenem resistant Pseudomonas aeruginosaisolates contained blaVIM-2 and blaIMP-1 genes respectively. No SPM-1gene was found in the examined samples.Conclusion: Resistance of P. aeruginosa isolates to imipenem due to MBL enzymes is increasing in Ahavaz. Becauseof clinical significance of this kind of resistance, rapid detection of MBL producing strains and followed by appropriatetreatment is necessary to prevent the spreading of these organisms.

  3. Multidrug-resistant Acinetobacter baumannii strains carrying the bla(OxA-23) and the bla(GES-11) genes in a neonatology center in Tunisia. (United States)

    Charfi-Kessis, Karama; Mansour, Wejdene; Ben Haj Khalifa, Anis; Mastouri, Maha; Nordmann, Patrice; Aouni, Mahjoub; Poirel, Laurent


    Multidrug-resistant and difficult-to-treat Acinetobacter baumannii may be responsible for nosocomial infections. The production of carbapenem-hydrolyzing class D β-lactamases (CHDLs) and extended-spectrum β-lactamase (ESBLs) of the GES type possessing a carbapenemase activity has been increasingly reported worldwide in A. baumannii. The aim of this study was to analyze the resistance mechanisms of two carbapenem resistant A. baumannii clinical isolates recovered in a neonatology center in the center-east of Tunisia. Two carbapenem resistant A. baumannii isolates were recovered. The first isolate co-harbored the blaGES-11 ESBL gene and the blaOxA-23 CHDL gene. Analyses of the genetic location indicated that the blaGES-11 gene was plasmid located (Gr6). However, the blaOxA-23 gene was located on the chromosome. The second strain had only the blaOxA-23 CHDL gene, which was plasmid located. This study showed the first description of the GES-type β-lactamase in A. baumannii in Tunisia.

  4. Detection and characterization of extended-spectrum β-lactamases (blaCTX-M-1 and blaSHV producing Escherichia coli, Salmonella spp. and Klebsiella pneumoniae isolated from humans in Mizoram

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    Iadarilin Warjri


    Full Text Available Aim: The present study was conducted to isolate and characterize the extended spectrum β-lactamases (ESBLs producing enteric bacteria in human beings in Mizoram, India. Materials and Methods: Fecal samples were collected from human beings with or without the history of diarrhea from different hospitals of Mizoram. Samples were processed for isolation and identification of Escherichia coli, Salmonella and Klebsiella pneumoniae. All the isolates were subjected to antibiotic sensitivity assays. Phenotypically, ESBLs production ability was determined by double discs synergy test (DDST method. ESBLs producing isolates were subjected to polymerase chain reaction (PCR for detection of ESBLs genes. Plasmids were cured by acridine orange. Transfer of resistance from a donor to recipient strains was done by in vitro horizontal method. Results: A total of 414 enteric bacteria were isolated from 180 fecal samples (113 were from diarrheic patients and 67 were from non-diarrheic patients, of which 333 (80.44%, 52 (12.56%, and 29 (7.00% were E. coli, K. pneumoniae and Salmonella spp., respectively. Double discs synergy test (DDST exhibited 72 (21.62% E. coli, 12 (23.08% K. pneumoniae and 4 (13.79% Salmonella spp. were ESBLs producers. Altogether, 24 (13.04% isolates were found to be positive for at least one resistance genes under this study. A total of 36 (8.70% E. coli, 4 (0.97% K. pneumoniae and 2 (0.48% Salmonella spp. were found to be positive for blaCTX-M-1 gene by PCR. Similarly, 5 (1.21% E. coli and 4 (0.97% K. pneumoniae isolates were found to be positive for blaSHV gene. A total of 3 (0.72% K. pneumoniae isolates were recorded as positive for both blaCTX-M-1 and blaSHV genes. All the isolates were carrying plasmids ranging between 0.9 kb and ~30 kb. The resistance plasmid could not be transferred to a recipient by in vitro horizontal gene transfer method. Conclusion: ESBLs producing enteric bacteria are circulating in human population in North

  5. Occurrence of blaNDM-1 & absence of blaKPC genes encoding carbapenem resistance in uropathogens from a tertiary care centre from north India

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    Balvinder Mohan


    Interpretation & conclusions: The bla NDM-1 gene was absent in our isolates obtained during 2008 but was present amongst Enterobacteriaceae isolated in 2012. The bla KPC gene was also not found. Nine isolates obtained during the two years had multiple genes encoding carbapenemases confirming the previous reports of emergence of GNB containing genes encoding multiple carbapenemases. Typing using BOX-PCR indicated that this emergence was not because of clonal expansion of a single strain, and multiple strains were circulating at a single point of time.

  6. Carbapenem-resistant Acinetobacter pittii strain harboring blaOXA-72 from Brazil. (United States)

    Chagas, Thiago Pavoni Gomes; Tavares E Oliveira, Thamirys Rachel; D'Alincourt Carvalho-Assef, Ana Paula; Albano, Rodolpho M; Asensi, Marise Dutra


    In this study, we report the isolation of OXA-72-producing Acinetobacter pittii in Brazil. A carbapenem-resistant A. pittii strain was recovered from a hospitalized female patient from Espírito Santo, Southeastern Brazil. PCR screening and DNA sequencing allowed us to identify the presence of blaOXA-72. We observed blaOXA-72 in a ~11kb plasmid and flanked by XerC/XerD-binding sites.

  7. Evaluation of LAMP assay using phenotypic tests and conventional PCR for detection of blaNDM-1 and blaKPC genes among carbapenem-resistant clinical Gram-negative isolates. (United States)

    Solanki, Rachana; Vanjari, Lavanya; Ede, Nagapriyanka; Gungi, Akhila; Soory, Amarendranath; Vemu, Lakshmi


    Carbapenem-resistant pathogens cause infections associated with significant morbidity and mortality. This study evaluates the use of the loop-mediated isothermal amplification (LAMP) assay for rapid and cost-effective detection of bla(NDM-1) and bla(KPC) genes among carbapenem-resistant Gram-negative bacteria in comparison with conventional PCR and existing phenotypic methods. A total of 60 carbapenem-resistant clinical isolates [Escherichia coli (15), Klebsiella pneumoniae (22), Acinetobacter baumannii (23)] were screened for the presence of carbapenemases (bla(KPC) and bla(NDM-1)) using phenotypic methods such as the modified Hodge test (MHT) and combined disc test (CDT) and molecular methods such as conventional PCR and LAMP assay. In all, 47/60 isolates (78.3%) were MHT positive while 48 isolates were positive by CDT [46.6% positive with EDTA, 30% with 3' aminophenylboronic acid (APB) plus EDTA and 1.6% with APB alone]. Isolates showing CDT positivity with EDTA or APB contained bla(NDM-1) and bla(KPC) genes, respectively. bla(NDM-1) was present as a lone gene in 28 isolates (46.7%) and present together with the bla(KPC) gene in 19 isolates (31.7%). Only one E. coli isolate had a lone bla(KPC) gene. The LAMP assay detected either or both bla(NDM-1) and bla(KPC) genes in four isolates that were missed by conventional PCR. Neither gene could be detected in 12 (20%) isolates. The LAMP assay has greater sensitivity, specificity and rapidity compared to the phenotypic methods and PCR for the detection of bla(NDM-1) and bla(KPC). With a turnaround time of only 2-3 h, the LAMP assay can be considered a point-of-care assay.

  8. Global Escherichia coli Sequence Type 131 Clade with blaCTX-M-27 Gene. (United States)

    Matsumura, Yasufumi; Pitout, Johann D D; Gomi, Ryota; Matsuda, Tomonari; Noguchi, Taro; Yamamoto, Masaki; Peirano, Gisele; DeVinney, Rebekah; Bradford, Patricia A; Motyl, Mary R; Tanaka, Michio; Nagao, Miki; Takakura, Shunji; Ichiyama, Satoshi


    The Escherichia coli sequence type (ST) 131 C2/H30Rx clade with the blaCTX-M-15 gene had been most responsible for the global dissemination of extended-spectrum β-lactamase (ESBL)-producing E. coli. ST131 C1/H30R with blaCTX-M-27 emerged among ESBL-producing E. coli in Japan during the late 2000s. To investigate the possible expansion of a single clade, we performed whole-genome sequencing for 43 Japan and 10 global ST131 isolates with blaCTX-M-27 (n = 16), blaCTX-M-14 (n = 16), blaCTX-M-15 (n = 13), and others (n = 8). We also included 8 ST131 genomes available in public databases. Core genome-based analysis of 61 isolates showed that ST131 with blaCTX-M-27 from 5 countries formed a distinct cluster within the C1/H30R clade, named C1-M27 clade. Accessory genome analysis identified a unique prophage-like region, supporting C1-M27 as a distinct clade. Our findings indicate that the increase of ESBL-producing E. coli in Japan is due mainly to emergence of the C1-M27 clade.

  9. How to identify Raoultella spp. including R. ornithinolytica isolates negative for ornithine decarboxylase? The reliability of the chromosomal bla gene. (United States)

    Walckenaer, Estelle; Leflon-Guibout, Véronique; Nicolas-Chanoine, Marie-Hélène


    Although Raoultella planticola and Raoultella ornithinolytica were described more than 20 years ago, identifying them remains difficult. The reliability of the chromosomal bla gene for this identification was evaluated in comparison with that of the 16S rDNA and rpoB genes in 35 Raoultella strains from different origins. Of the 26 strains previously identified as R. planticola by biochemical tests alone or in association with molecular methods, 21 harboured a bla gene with 99.8% identity with the bla gene of two reference R. ornithinolytica strains (bla(ORN) gene) and 5 harboured a bla gene with 99.2% identity with the bla gene of two reference R. planticola strains (bla(PLA) gene). The 9 isolates previously identified as R. ornithinolytica harboured a bla(ORN) gene. The bla gene-based identification was confirmed by 16S rDNA and rpoB sequencing. The 21 isolates newly identified as R. ornithinolytica had a test negative for ornithine decarboxylase (ODC). Molecular experiments suggested one copy of ODC-encoding gene in both ODC-negative R. ornithinolytica and R. planticola strains and two copies in ODC-positive R. orninthinolytica strains. Analysis of the 35 bla genes allowed us (i) to confirm an identity of only 94% between the bla genes of the two Raoultella species while this identity was > 98% for rpoB and > 99% for 16S rDNA genes and (ii) to develop and successfully apply a bla PCR RFLP assay for Raoultella spp. identification. Overall, this study allowed us to discover ODC-negative R. ornithinolytica and to provide a reliable Raoultella identification method widely available as not requiring sequencing equipment.

  10. Identification of Acinetobacter baumannii by detection of the blaOXA-51-like carbapenemase gene intrinsic to this species. (United States)

    Turton, Jane F; Woodford, Neil; Glover, Judith; Yarde, Susannah; Kaufmann, Mary E; Pitt, Tyrone L


    bla(OXA-51-like) was sought in clinical isolates of Acinetobacter species in a multiplex PCR, which also detects bla(OXA-23-like) and class 1 integrase genes. All isolates that gave a band for bla(OXA-51-like) identified as A. baumannii. This gene was detected in each of 141 isolates of A. baumannii but not in those of 22 other Acinetobacter species.

  11. Characterization of the genetic environment of the blaKPC-2 gene among Klebsiella pneumoniae isolates from a Chinese Hospital. (United States)

    Shen, Pinghua; Zhang, Ying; Li, Gang; Jiang, Xiaofei


    Infection caused by carbapenem-resistant Klebsiella pneumoniae has become a major healthcare threat and KPC-2 enzyme is a dominant factor mediating carbapenems resistance in K. pneumoniae. This study was designed to determine the genetic environment of blaKPC-2, which prevailed in clinical K. pneumoniae isolates recovered in Huashan Hospital, Shanghai, China. Forty-two clinical isolates were included in this study by blaKPC-2 screening. After multilocus sequence typing and plasmid analyses of PCR-based replicon typing (PBRT), junction PCR, mapping PCR and crossing PCR assays, primer walking, and amplicon sequencing were used to analyze the genetic environment of the blaKPC-2 gene. ST423, ST65, ST977, and ST11 were all detected in KPC-2-producing K. pneumoniae. Two types of blaKPC-2-bearing genetic structure were found: Tn1721-blaKPC-2-Tn3 and Tn1721-blaKPC-2-ΔTn3-IS26; and were carried in IncX and IncFII plasmids, respectively. In conclusion, the genetic environment of the blaKPC-2 gene was diverse and Tn1721-blaKPC-2-ΔTn3-IS26 was dominant in clinical K. pneumoniae isolates in Huashan Hospital. This study sheds some light on the genetic environment and should foster further studies about the mechanism of the blaKPC-2 dissemination.

  12. Beta-Lactamase Encoded Genes blaTEM and blaCTX Among Acinetobacter baumannii Species Isolated From Medical Devices of Intensive Care Units in Tehran Hospitals (United States)

    Khalilzadegan, Sara; Sade, Mojtaba; Godarzi, Hussein; Eslami, Gita; Hallajzade, Masoumeh; Fallah, Fatemeh; Yadegarnia, Davood


    Background Excessive consumption of antimicrobial materials in hospitals is considered as the main encoder leading to the emergence, development and acquisition of new bacterial resistance to beta-lactamase. Objectives Owing to the lack of proper information regarding the mechanism of the bacterial resistance to antibiotics and responsible genes in the country, the current study aimed to consider the resistance or sensitivity of the Acinetobacter baumannii multi drug resistant (MDR) isolates facing 2% glutaraldehyde. The study was conducted in the selected intensive care units in Tehran hospitals, Iran, in 2013. Materials and Methods In this study conducted over a period of 10 months, A. baumannii species were isolated by bacterial culture following biochemical tests from intensive care units (ICUs) of some hospitals in Tehran, Iran (Fayazbaksh, Taleghani, Imam Khomeini, Valiasr, Labafinejad). The resistance and sensitivity of the isolates to antibiotics were considered according to the clinical and laboratory standard institute CLSI (2012) guidelines. By multiplex PCR method, blaCTX and blaTEM genes were detected and finally, MDR strains were treated with 2% glutaraldehyde. PCR was used for each strain of MDR using specific primers. Results In the current study, 131 A. baumannii isolates (22.3%) out of 588 were studied. The level of resistance to various antibiotics was in the range of 69.4% to 100%. The frequencies of blaTEM and blaCTX genes were 3.2% and 19.4%, respectively. MIC50% and MIC90% of imipenem and meropenem antibiotics were 32 ± 1 µg/mL and 64 ± 1 µg/mL, respectively (P < 0.9). However no resistance to glutaraldehyde was observed. Different bands of MDR strains were observed in the PCR product by electrophoresis. Conclusions It seems that besides the variety and prevalence of blaTEM and blaCTX, enormous mechanisms such as porin and leaking systems (efflux pumps) are responsible for the information of the A. baumannii resistance to disinfectants

  13. Initial Assessment of the Molecular Epidemiology of blaNDM-1 in Colombia (United States)

    Rojas, Laura J.; Wright, Meredith S.; De La Cadena, Elsa; Motoa, Gabriel; Hujer, Kristine M.; Villegas, Maria V.


    We report complete genome sequences of four blaNDM-1-harboring Gram-negative multidrug-resistant (MDR) isolates from Colombia. The blaNDM-1 genes were located on 193-kb Inc FIA, 178-kb Inc A/C2, and 47-kb (unknown Inc type) plasmids. Multilocus sequence typing (MLST) revealed that these isolates belong to sequence type 10 (ST10) (Escherichia coli), ST392 (Klebsiella pneumoniae), and ST322 and ST464 (Acinetobacter baumannii and Acinetobacter nosocomialis, respectively). Our analysis identified that the Inc A/C2 plasmid in E. coli contained a novel complex transposon (Tn125 and Tn5393 with three copies of blaNDM-1) and a recombination “hot spot” for the acquisition of new resistance determinants. PMID:27067339

  14. Multiplex real-time PCR assay for detection and classification of Klebsiella pneumoniae carbapenemase gene (bla KPC) variants. (United States)

    Chen, Liang; Mediavilla, José R; Endimiani, Andrea; Rosenthal, Marnie E; Zhao, Yanan; Bonomo, Robert A; Kreiswirth, Barry N


    Carbapenem resistance mediated by plasmid-borne Klebsiella pneumoniae carbapenemases (KPC) is an emerging problem of significant clinical importance in Gram-negative bacteria. Multiple KPC gene variants (bla(KPC)) have been reported, with KPC-2 (bla(KPC-2)) and KPC-3 (bla(KPC-3)) associated with epidemic outbreaks in New York City and various international settings. Here, we describe the development of a multiplex real-time PCR assay using molecular beacons (MB-PCR) for rapid and accurate identification of bla(KPC) variants. The assay consists of six molecular beacons and two oligonucleotide primer pairs, allowing for detection and classification of all currently described bla(KPC) variants (bla(KPC-2) to bla(KPC-11)). The MB-PCR detection limit was 5 to 40 DNA copies per reaction and 4 CFU per reaction using laboratory-prepared samples. The MB-PCR probes were highly specific for each bla(KPC) variant, and cross-reactivity was not observed using DNA isolated from several bacterial species. A total of 457 clinical Gram-negative isolates were successfully characterized by our MB-PCR assay, with bla(KPC-3) and bla(KPC-2) identified as the most common types in the New York/New Jersey metropolitan region. The MB-PCR assay described herein is rapid, sensitive, and specific and should be useful for understanding the ongoing evolution of carbapenem resistance in Gram-negative bacteria. As novel bla(KPC) variants continue to emerge, the MB-PCR assay can be modified in response to epidemiologic developments.

  15. Crystal Structure of a Dimerized Cockroach Allergen Bla g 2 Complexed with a Monoclonal Antibody

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    Li, Mi; Gustchina, Alla; Alexandratos, Jerry; Wlodawer, Alexander; Wünschmann, Sabina; Kepley, Christopher L.; Chapman, Martin D.; Pomes, Anna (INDOOR Bio.); (VCU); (NIH)


    The crystal structure of a 1:1 complex between the German cockroach allergen Bla g 2 and the Fab' fragment of a monoclonal antibody 7C11 was solved at 2.8-{angstrom} resolution. Bla g 2 binds to the antibody through four loops that include residues 60-70, 83-86, 98-100, and 129-132. Cation-{pi} interactions exist between Lys-65, Arg-83, and Lys-132 in Bla g 2 and several tyrosines in 7C11. In the complex with Fab', Bla g 2 forms a dimer, which is stabilized by a quasi-four-helix bundle comprised of an {alpha}-helix and a helical turn from each allergen monomer, exhibiting a novel dimerization mode for an aspartic protease. A disulfide bridge between C51a and C113, unique to the aspartic protease family, connects the two helical elements within each Bla g 2 monomer, thus facilitating formation of the bundle. Mutation of these cysteines, as well as the residues Asn-52, Gln-110, and Ile-114, involved in hydrophobic interactions within the bundle, resulted in a protein that did not dimerize. The mutant proteins induced less {beta}-hexosaminidase release from mast cells than the wild-type Bla g 2, suggesting a functional role of dimerization in allergenicity. Because 7C11 shares a binding epitope with IgE, the information gained by analysis of the crystal structure of its complex provided guidance for site-directed mutagenesis of the allergen epitope. We have now identified key residues involved in IgE antibody binding; this information will be useful for the design of vaccines for immunotherapy.

  16. Clonal spread of blaOXA-72-carrying Acinetobacter baumannii sequence type 512 in Taiwan. (United States)

    Kuo, Han-Yueh; Hsu, Po-Jui; Chen, Jiann-Yuan; Liao, Po-Cheng; Lu, Chia-Wei; Chen, Chang-Hua; Liou, Ming-Li


    This is the first report to show an insidious outbreak of armA- and blaOXA-72-carrying Acinetobacter baumannii sequence type 512 (ST512) at a study hospital in northern Taiwan. Multilocus sequence typing revealed that this was a ST512 clone. All of the isolates with ST512 carried a novel 12,056-bp repGR2 in combination with a repGR12-type plasmid. This plasmid, designated pAB-ML, had one copy of the blaOXA-72 gene that was flanked by XerC/XerD-like sites and conferred resistance to carbapenems.

  17. XML Determination of Phylogenetic Group and Prevalence of blaCTX-M and blaCTX-M-15 Genes in Escherichia Coli Isolates from Intestinal and Urinary Tract Infections in under Five- Year- Old Children

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    Momeni, F. (MSc


    Full Text Available Background and Objective: CTX-M type extended spectrum beta-lactamases is a rapidly expanding group of enzymes encountered with increasing fre‌quency, especially, in Escherichia coli (E. coli. There are a few reports on phylogenetic background of E. coli isolates from clinical sources of under five-year- old children in Iran. The purpose of this study was phylotyping of E. coli isolates having blaCTX-M and blaCTX-M-15 genes from under five-year- old children with diarrhea and urinary tract infection (UTI. Material and Methods: A total of 121 E. coli isolates (75 diarrheas and 46 UTI were obtained and identified as E. coli based on standard bacteriological tests. DNA was extracted from E. coli isolates by alkaline lysis method. PCR assay was used because of high frequency of blaCTX-M and blaCTX-M-15 genes in the isolates and also determination of phylogenetic group/subgroups by detection of yjaA and chuA genes and fragment TspE4.C2. Results: The isolates belonged to four phylogenetic groups A (48.77%, B1 (14.04%, B2 (11.57%, and D (25.62%. In the diarrheic isolates,17.37% were positive for blaCTX-M and 14.04% of isolates possessed both blaCTX-M and blaCTX-15genes.Out of 46 UTI isolates, 21.73% were positive for blaCTX-M and 15.21% for blaCTX-M and blaCTX-M-15 genes. Conclusion: A rather high prevalence of E. coli isolates with blaCTX-M and blaCTX-M-15 genes was observed in fewer than five-year- old children in Khoramabad city. Phylotyping of isolates possessing blaCTX-M and blaCTX-15genes showed that most of them belonge to A and D phylo-groups

  18. Non-O1/Non-O139 Vibrio cholerae Avian Isolate from France Cocarrying the bla(VIM-1) and bla(VIM-4) Genes. (United States)

    Aberkane, Salim; Compain, Fabrice; Barraud, Olivier; Ouédraogo, Abdoul-Salam; Bouzinbi, Nicolas; Vittecoq, Marion; Jean-Pierre, Hélène; Decré, Dominique; Godreuil, Sylvain


    We describe here a non-O1/non-O139 Vibrio cholerae isolate producing both VIM-1 and VIM-4 carbapenemases. It was isolated from a yellow-legged gull in southern France. The blaVIM genes were part of a class 1 integron structure located in an IncA/C plasmid. This study emphasizes the presence of carbapenemase genes in wildlife microbiota.

  19. Genetic characteristics of blaNDM-1-positive plasmid in Citrobacter freundii isolate separated from a clinical infectious patient. (United States)

    Du, Xiao-Xing; Wang, Jian-Feng; Fu, Ying; Zhao, Feng; Chen, Yan; Wang, Hai-Ping; Yu, Yun-Song


    This study reports an infectious case involving an (NDM-1)-producing Citrobacter freundii and further explored the potential threat of the bla(NDM-1) gene by analysing the characteristics of the (NDM-1)-encoding plasmid sequence. A bla(NDM-1)-positive C. freundii with high resistance to carbapenems was separated from a clinical patient suffering from a urinary tract infection. S1 nuclease-based plasmid analysis followed by Southern blot hybridization, a conjugation experiment and electrotransformation confirmed that the bla(NDM-1) gene was located on a plasmid. High-throughput sequencing of the bla(NDM-1)-positive plasmid (pCFNDM-CN) showed that it was a 54 kb IncX-type plasmid and contained a backbone region and a variable region with two β-lactamase genes (bla(NDM-1) and bla(SHV-12)). The NDM-1 composite transposon in the variable region was surrounded by IS26 and IS5-truncated ISAba125, and shared a high sequence similarity to the bla(NDM-1) surrounding structure in Acinetobacter spp. Our research suggested that the NDM-1 composite transposon might play an essential role in mobilization of the bla(NDM-1) gene from Acinetobacter spp. to Enterobacteriaceae.

  20. First Indian report of IncX3 plasmid carrying blaNDM-7 in Escherichia coli from bloodstream infection: potential for rapid dissemination. (United States)

    Devanga Ragupathi, N K; Muthuirulandi Sethuvel, D P; Gajendiran, R; Daniel, J L K; Walia, K; Veeraraghavan, B


    Enterobacteriaceae with blaNDM-7 is only infrequently observed. Self-transmissible plasmids carrying the blaNDM gene increase the dissemination of carbapenem resistance in developing countries. This study investigates the whole genome sequence of a blaNDM-7-positive Escherichia coli. The isolate was an extended-spectrum β-lactamase producer by combined disc diffusion test and carbapenemase producer by CarbaNP method. Sequencing results revealed the isolate as E. coli ST-167 with IncX3 plasmid carrying blaNDM-7 in addition to blaTEM-1 and blaCMY-42 genes. The identification of IncX3-blaNDM-7 combination is the first report in India where blaNDM-7 is known to cause higher resistance to carbapenems compared to its variants.

  1. Genetic Structure Associated with blaOXA-18, Encoding a Clavulanic Acid-Inhibited Extended-Spectrum Oxacillinase▿ (United States)

    Naas, Thierry; Namdari, Fatemeh; Bogaerts, Pierre; Huang, Te-Din; Glupczynski, Youri; Nordmann, Patrice


    The genetic environment of the blaOXA-18 gene encoding a peculiar clavulanic acid-inhibitable Ambler class D extended-spectrum β-lactamase was determined from the prototype OXA-18-producing Pseudomonas aeruginosa MUS clinical isolate. An 8.2-kb genomic DNA fragment containing blaOXA-18 was cloned from P. aeruginosa MUS. Although most oxacillinases are located in integrons, blaOXA-18 lacked gene cassette-specific features. It was bracketed by two duplicated sequences containing ISCR19, a novel insertion sequence of the ISCR family of mobile elements; ΔintI1, a truncated integrase gene; and a truncated Δaac6′-Ib gene cassette. It is likely that ISCR19 was at the origin of the blaOXA-18 gene mobilization by a rolling-circle transposition event followed by homologous recombination. Furthermore, analysis of the cloned genomic DNA fragment revealed the presence of the integron-containing blaOXA-20 gene. Concomitantly, three P. aeruginosa clinical isolates, displaying a synergy image as determined by double-disk diffusion tests on cloxacillin-containing plates, were isolated from three patients hospitalized in different wards over a 9-month period at the Saint-Luc University hospital (Brussels, Belgium). These isolates were positive by PCR for blaOXA-18 and blaOXA-20 genes, genetically related to P. aeruginosa MUS as determined by pulsed-field gel electrophoresis, and carried the same blaOXA-18/blaOXA-20-associated genetic structures. This report characterized the genetic elements likely at the origin of blaOXA-18 gene mobilization in P. aeruginosa and suggests the spread of oxacillin-type extended-spectrum β-lactamases in P. aeruginosa at the Saint-Luc University hospital of Brussels, Belgium. PMID:18663027

  2. blaKPC RNA Expression Correlates with Two Transcriptional Start Sites but Not Always with Gene Copy Number in Four Genera of Gram-Negative Pathogens▿


    Roth, Amanda L.; Kurpiel, Philip M.; Lister, Philip D.; Hanson, Nancy D.


    Klebsiella pneumoniae carbapenemase (KPC)-producing organisms are therapeutically and diagnostically challenging. It is possible that blaKPC gene expression plays a role in the variability observed in clinical susceptibility testing. blaKPC transformants together with 10 clinical isolates representing four genera were evaluated for blaKPC copy number and gene expression and correlated with β-lactam MIC data. The data suggest that mechanisms other than gene copy number and expression of blaKPC...

  3. First report of the blaVIM gene in environmental isolates of Buttiauxella sp. (United States)

    Pitondo-Silva, André; Martins, Vinicius Vicente; Stehling, Eliana Guedes


    Several works have demonstrated the presence of metallo-β-lactamases (MBLs) in clinical bacteria. However, in environmental isolates, few works have reported on these enzymes. In this study, we report for the first time two environmental isolates of Buttiauxella sp. recovered from chrysanthemum plantations in Brazil containing blaVIM gene and producing MBLs.

  4. Identification of bla KPC-2 on different plasmids of three Morganella morganii isolates. (United States)

    Shi, D-S; Wang, W-P; Kuai, S-G; Shao, H-F; Huang, M


    Three Morganella morganii strains resistant to carbapenems were recovered from the surgical intensive care unit (SICU) in our hospital. Carbapenemases and extended-spectrum β-lactamases (ESBLs) were respectively detected by the modified Hodge test and the modified Clinical and Laboratory Standards Institute (CLSI) ESBL confirmatory test in all isolates. Amplification of whole-cell and plasmid DNAs extracted from isolates with primers specific for the bla (KPC) produced an amplicon confirmed to be bla (KPC-2) by sequence analysis. Pulsed-field gel electrophoresis (PFGE) typing revealed that three isolates belonged to two closely related types. Plasmids electrophoresis and restriction analysis revealed that the bla (KPC-2) was located on different plasmids. The transfer of carbapenem resistance from the three original isolates to Escherichia coli EC600 was successful by conjugation. An examination of the outer membrane proteins showed a lack of a 38-kDa outer membrane protein (OMP) compared with M. morganii susceptible to carbapenems. The production of KPC-2 and ESBLs, combined with OMP deficiency, resulted in high-level carbapenem resistance in the M. morganii strains. The genetic environment around bla (KPC-2) analysis revealed that this β-lactamase was located on the same mobile genetic elements which could transfer between different plasmids.

  5. Diversity and evolution of blaZ from Staphylococcus aureus and coagulase-negative staphylococci

    DEFF Research Database (Denmark)

    Olsen, John E.; Christensen, Henrik; Aarestrup, Frank Møller


    NS) and Staphylococcus aureus of bovine origin. Methods: blaZ was detected in 143 strains of penicillin-resistant S. aureus and CoNS from five Danish cattle herds (n = 25/23), random CoNS isolates from Denmark (n = 37), a collection of S. aureus from six different countries (n = 52), humans in Denmark (n = 3) and beta...... and sequences retrieved from public databases were compared. A phylogenetic tree showed that blaZ exists in three evolutionary lines: one group was of plasmid origin, one group was of chromosomal origin and one intermediate group. Sixty-nine sequence types were demonstrated. They translated into 11 BlaZ protein...... types. The major types all contained strains of both human and bovine origin, and more than one Staphylococcus species, demonstrating a shared gene pool. In a comparison of S. aureus and CoNS obtained from five Danish cattle herds, the same type of blaZ was only detected in one case. Conclusions...

  6. Genetic structures at the origin of acquisition of the beta-lactamase bla KPC gene. (United States)

    Naas, Thierry; Cuzon, Gaelle; Villegas, Maria-Virginia; Lartigue, Marie-Frédérique; Quinn, John P; Nordmann, Patrice


    Genetic structures surrounding the carbapenem-hydrolyzing Ambler class A bla KPC gene were characterized in several KPC-positive Klebsiella pneumoniae and Pseudomonas aeruginosa strains isolated from the United States, Colombia, and Greece. The bla KPC genes were associated in all cases with transposon-related structures. In the K. pneumoniae YC isolate from the United States, the beta-lactamase bla KPC-2 gene was located on a novel Tn3-based transposon, Tn4401. Tn4401 was 10 kb in size, was delimited by two 39-bp imperfect inverted repeat sequences, and harbored, in addition to the beta-lactamase bla KPC-2 gene, a transposase gene, a resolvase gene, and two novel insertion sequences, ISKpn6 and ISKpn7. Tn4401 has been identified in all isolates. However, two isoforms of this transposon were found: Tn4401a was found in K. pneumoniae YC and K. pneumoniae GR from the United States and Greece, respectively, and differed by a 100-bp deletion, located just upstream of the bla KPC-2 gene, compared to the sequence of Tn4401b, which was found in the Colombian isolates. In all isolates tested, Tn4401 was flanked by a 5-bp target site duplication, the signature of a recent transposition event, and was inserted in different open reading frames located on plasmids that varied in size and nature. Tn4401 is likely at the origin of carbapenem-hydrolyzing beta-lactamase KPC mobilization to plasmids and its further insertion into various-sized plasmids identified in nonclonally related K. pneumoniae and P. aeruginosa isolates.

  7. Hydrolysis of Clavulanate by Mycobacterium tuberculosis β-Lactamase BlaC Harboring a Canonical SDN Motif (United States)

    Soroka, Daria; Li de la Sierra-Gallay, Inès; Dubée, Vincent; Triboulet, Sébastien; van Tilbeurgh, Herman; Compain, Fabrice; Ballell, Lluis; Barros, David; Mainardi, Jean-Luc


    Combinations of β-lactams with clavulanate are currently being investigated for tuberculosis treatment. Since Mycobacterium tuberculosis produces a broad spectrum β-lactamase, BlaC, the success of this approach could be compromised by the emergence of clavulanate-resistant variants, as observed for inhibitor-resistant TEM variants in enterobacteria. Previous analyses based on site-directed mutagenesis of BlaC have led to the conclusion that this risk was limited. Here, we used a different approach based on determination of the crystal structure of β-lactamase BlaMAb of Mycobacterium abscessus, which efficiently hydrolyzes clavulanate. Comparison of BlaMAb and BlaC allowed for structure-assisted site-directed mutagenesis of BlaC and identification of the G132N substitution that was sufficient to switch the interaction of BlaC with clavulanate from irreversible inactivation to efficient hydrolysis. The substitution, which restored the canonical SDN motif (SDG→SDN), allowed for efficient hydrolysis of clavulanate, with a more than 104-fold increase in kcat (0.41 s−1), without affecting the hydrolysis of other β-lactams. Mass spectrometry revealed that acylation of BlaC and of its G132N variant by clavulanate follows similar paths, involving sequential formation of two acylenzymes. Decarboxylation of the first acylenzyme results in a stable secondary acylenzyme in BlaC, whereas hydrolysis occurs in the G132N variant. The SDN/SDG polymorphism defines two mycobacterial lineages comprising rapidly and slowly growing species, respectively. Together, these results suggest that the efficacy of β-lactam–clavulanate combinations may be limited by the emergence of resistance. β-Lactams active without clavulanate, such as faropenem, should be prioritized for the development of new therapies. PMID:26149997

  8. Mechanisms Involved in Acquisition of blaNDM Genes by IncA/C2 and IncFIIY Plasmids. (United States)

    Wailan, Alexander M; Sidjabat, Hanna E; Yam, Wan Keat; Alikhan, Nabil-Fareed; Petty, Nicola K; Sartor, Anna L; Williamson, Deborah A; Forde, Brian M; Schembri, Mark A; Beatson, Scott A; Paterson, David L; Walsh, Timothy R; Partridge, Sally R


    blaNDM genes confer carbapenem resistance and have been identified on transferable plasmids belonging to different incompatibility (Inc) groups. Here we present the complete sequences of four plasmids carrying a blaNDM gene, pKP1-NDM-1, pEC2-NDM-3, pECL3-NDM-1, and pEC4-NDM-6, from four clinical samples originating from four different patients. Different plasmids carry segments that align to different parts of the blaNDM region found on Acinetobacter plasmids. pKP1-NDM-1 and pEC2-NDM-3, from Klebsiella pneumoniae and Escherichia coli, respectively, were identified as type 1 IncA/C2 plasmids with almost identical backbones. Different regions carrying blaNDM are inserted in different locations in the antibiotic resistance island known as ARI-A, and ISCR1 may have been involved in the acquisition of blaNDM-3 by pEC2-NDM-3. pECL3-NDM-1 and pEC4-NDM-6, from Enterobacter cloacae and E. coli, respectively, have similar IncFIIY backbones, but different regions carrying blaNDM are found in different locations. Tn3-derived inverted-repeat transposable elements (TIME) appear to have been involved in the acquisition of blaNDM-6 by pEC4-NDM-6 and the rmtC 16S rRNA methylase gene by IncFIIY plasmids. Characterization of these plasmids further demonstrates that even very closely related plasmids may have acquired blaNDM genes by different mechanisms. These findings also illustrate the complex relationships between antimicrobial resistance genes, transposable elements, and plasmids and provide insights into the possible routes for transmission of blaNDM genes among species of the Enterobacteriaceae family.

  9. High prevalence of blaCTX-M group genes in Aeromonas dhakensis isolated from aquaculture fish species in South Korea. (United States)

    Yi, Seung-Won; Chung, Tae-Ho; Joh, Seong-Joon; Park, Chul; Park, Byoung-Yong; Shin, Gee-Wook


    The prevalence of resistant genes against β-lactams in 119 Aeromonas strains was determined. A large number (99.2%) of the present fish strains were resistant to one or more β- lactams including ceftiofur, amoxicillin-clavulanic acid, ampicillin, piperacillin and cefpodoxime. Among antibiotic resistance phenotypes, the simultaneous resistance to all β-lactams occurred in 25.2% (n=30) of all strains, which consisted of 18 strains of A. dhakensis, 8 strains of A. caviae, 2 strains of A. hydrophila and only one strain of A. veronii. For exploring genetic background of the antibiotic resistances, multiple PCR assays were subjected to detect β-lactamase-encoding genes, bla(TEM), bla(OXA-B) and bla(CTX-M). In the results, the bla(TEM-1) gene was harbored in all strains, whereas only 3 strains harbored bla(OXA) gene. In the case of bla(CTX-M) gene, the gene was detected in 21.0% (25 out of 119) of all strains, which countered with 80% (20 out of 25) of A. dhakensis, 8% (2 out of 25) of A. caviae and 12% (3 out of 25) of A. hydrophila. In addition, most of the bla(CTX-M) positive strains showed simultaneous resistance to all β-lactams (18 out of 30 strains). In sequence analysis for bla(CTX-M) genes detected, they were CTX-M group 1-encoding genes including bla(CTX-M-33) from 3 eel strains of A. dhakensis. Therefore, A. dhakensis obtained from cultured fish could represent a reservoir for spreading genes encoding CTX-M group 1 enzymes and hence should be carefully monitored, especially for its potential risk to public health.

  10. Functional Characterization of Tn4401, a Tn3-Based Transposon Involved in blaKPC Gene Mobilization


    G Cuzon; Naas, T; Nordmann, P


    The carbapenemase gene blaKPC, which is rapidly spreading worldwide, is located on a Tn3-based transposon, Tn4401. In a transposition-conjugation assay, Tn4401 was able to mobilize blaKPC-2 gene at a frequency of 4.4 × 10−6/recipient cell. A 5-bp target site duplication was evidenced upon each insertion without target site specificity. This study demonstrated that Tn4401 is an active transposon capable of mobilizing blaKPC genes at high frequency.

  11. Multiplex Real-Time PCR Assay for Detection and Classification of Klebsiella pneumoniae Carbapenemase Gene (blaKPC) Variants▿


    Chen, Liang; Mediavilla, José R.; Endimiani, Andrea; Rosenthal, Marnie E.; Zhao, Yanan; Robert A Bonomo; Kreiswirth, Barry N.


    Carbapenem resistance mediated by plasmid-borne Klebsiella pneumoniae carbapenemases (KPC) is an emerging problem of significant clinical importance in Gram-negative bacteria. Multiple KPC gene variants (blaKPC) have been reported, with KPC-2 (blaKPC-2) and KPC-3 (blaKPC-3) associated with epidemic outbreaks in New York City and various international settings. Here, we describe the development of a multiplex real-time PCR assay using molecular beacons (MB-PCR) for rapid and accurate identific...

  12. Isolation of Enterobacter aerogenes carrying blaTEM-1 and blaKPC-3 genes recovered from a hospital Intensive Care Unit. (United States)

    Pulcrano, Giovanna; Pignanelli, Salvatore; Vollaro, Adriana; Esposito, Matilde; Iula, Vita Dora; Roscetto, Emanuela; Soriano, Amata Amy; Catania, Maria Rosaria


    Enterobacter aerogenes has recently emerged as an important hospital pathogen. In this study, we showed the emergence of E. aerogenes isolates carrying the blaKPC gene in patients colonized by carbapenem-resistant Klebsiella pneumoniae strains. Two multiresistant E. aerogenes isolates were recovered from bronchial aspirates of two patients hospitalized in the Intensive Care Unit at the "Santa Maria della Scaletta" Hospital, Imola. The antimicrobial susceptibility test showed the high resistance to carbapenems and double-disk synergy test confirmed the phenotype of KPC and AmpC production. Other investigation revealed that ESBL and blaKPC genes were carried on the conjugative pKpQIL plasmid. This is a relevant report in Italy that describes a nosocomial infection due to the production of KPC beta-lactamases by an E. aerogenes isolate in patients previously colonized by K. pneumoniae carbapenem-resistant. In conclusion, it's necessary a continuous monitoring of multidrug-resistant strains for the detection of any KPC-producing bacteria that could expand the circulation of carbapenem-resistant pathogens.

  13. blaGES carrying Pseudomonas aeruginosa isolates from a public hospital in Rio de Janeiro, Brazil

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    Flávia L. P. C. Pellegrino


    Full Text Available Previous analysis of Pseudomonas aeruginosa class-1 integrons from Rio de Janeiro, Brazil, revealed the blaGES gene in one isolate. We screened isolates of two widespread PFGE genotypes, A and B, at a public hospital in Rio, for the presence of blaGES. The gene was detected in all seven P. aeruginosa isolates belonging to genotype B. Three of the seven genotype-B isolates were resistant to amikacin, aztreonam, ceftazidime, cefepime, ciprofloxacin, gentamicin, imipenem, meropenem, piperacillin-tazobactam and ticarcillin-clavulanic acid. The other four isolates were resistant to all these agents, except gentamicin, imipenem, meropenem and piperacillin-tazobactam. A synergistic effect between ceftazidime and imipenem or clavulanic acid suggested the production of GES-type ESBL.

  14. Characterization of blaOXA-143 variants in Acinetobacter baumannii and Acinetobacter pittii. (United States)

    Zander, Esther; Bonnin, Rémy A; Seifert, Harald; Higgins, Paul G


    The acquired carbapenem-hydrolyzing oxacillinase (OXA) OXA-143 has thus far been detected only in Acinetobacter baumannii isolates from Brazil. The aim of this study was to characterize three OXA-143 variants: OXA-231 and OXA-253 from carbapenem-resistant A. baumannii isolates and OXA-255 in a carbapenem-susceptible Acinetobacter pittii isolate originating from Brazil, Honduras, and the United States, respectively. The 5' rapid amplification of cDNA ends (RACE) technique identified the same transcription initiation site for all blaOXA-143-like genes and revealed differences in the putative promoter regions. However, all cloned OXA-143 variants conferred carbapenem resistance on A. baumannii ATCC 17978 and OXA-255 conferred carbapenem resistance on A. pittii SH024, which was correlated with blaOXA-255 gene expression. This is the first description of OXA-143-like outside A. baumannii. Detection of OXA-143-like in the United States and Honduras indicates its dissemination through the American continent.

  15. Distribution of allelic variants of the chromosomal gene bla OXA-114-like in Achromobacter xylosoxidans clinical isolates. (United States)

    Traglia, German Matías; Almuzara, Marisa; Merkier, Andrea Karina; Papalia, Mariana; Galanternik, Laura; Radice, Marcela; Vay, Carlos; Centrón, Daniela; Ramírez, María Soledad


    Achromobacter xylosoxidans is increasingly being documented in cystic fibrosis patients. The bla(OXA-114) gene has been recognized as a naturally occurring chromosomal gene, exhibiting different allelic variants. In the population under study, the bla(OXA-114)-like gene was found in 19/19 non-epidemiological-related clinical isolates of A. xylosoxidans with ten different alleles including 1 novel OXA-114 variant.

  16. Caracterização espectral de áreas de gramíneas forrageiras infectadas com a doença "mela-das-sementes da braquiária" por meio de imagens CCD/CBERS-2 Spectral characterization of forage grasses infected with the disease "mela-das-sementes da braquiária" through CCD/CDBERS -2 images

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    José C. Rosatti


    Full Text Available Imagens CCD/CBERS-2, nas bandas espectrais CCD2, CCD3 e CCD4, dos anos de 2004 e 2005, de Mirante do Paranapanema - SP, foram transformadas em reflectância de superfície usando o modelo 5S de correção atmosférica e normalizadas radiometricamente. O objetivo principal foi caracterizar espectralmente áreas de pastagens de Brachiaria brizantha em fase de florescimento, isentas e infectadas com a doença "mela-das-sementes da braquiária", possibilitando a sua detecção por meio da comparação entre os valores de reflectância de superfície denominada de Fator de Reflectância Bidirecional de Superfície (FRBS. Teve-se, também, o objetivo de avaliar a eficácia das imagens CCD/CBERS-2 para a obtenção de respostas espectrais de pastagens. Os dosséis sadios e doentes da Brachiaria brizantha foram identificados por meio da análise dos valores de reflectância e dos dados observados no Índice de Estresse Hídrico Acumulativo Relativo da Cultura (ACWSI obtidos na área de estudo. Os resultados indicaram que as principais diferenças foram a diminuição da reflectância na banda CCD3 e o aumento da reflectância na banda CCD4 nas áreas doentes. A metodologia empregada com o uso de dados do sensor CCD/CBERS-2, associados ao ACWSI, mostrou-se eficaz para discriminar dosséis infectados com a "mela-das-sementes da braquiária".CCD/CBERS-2 images in the spectral bands of CCD2, CCD3 and CCD4 of the years 2004 and 2005, from Mirante do Paranapanema - SP (Brazil, were transformed into surface reflectance images using the 5S atmospheric correction model and radiometrically normalized. The main objective was to spectrally characterize pastures of Brachiaria brizantha in the flowering phase, exempt and infected with the disease "mela-das-sementes da braquiária" making it possible its detection through the comparison among the SBRF - Surface Bidirectional Reflectance Factor values. At the same time, it was aimed to evaluate the effectiveness of the

  17. Chromosomal Integration of the Klebsiella pneumoniae Carbapenemase Gene, blaKPC, in Klebsiella Species Is Elusive but Not Rare (United States)

    Chai, Weidong; Carroll, Joanne; Barry, Katie; Cherunvanky, Anita; Sebra, Robert; Kasarskis, Andrew; Peto, Tim E.; Walker, A. Sarah; Sifri, Costi D.; Crook, Derrick W.; Sheppard, Anna E.


    ABSTRACT Carbapenemase genes in Enterobacteriaceae are mostly described as being plasmid associated. However, the genetic context of carbapenemase genes is not always confirmed in epidemiological surveys, and the frequency of their chromosomal integration therefore is unknown. A previously sequenced collection of blaKPC-positive Enterobacteriaceae from a single U.S. institution (2007 to 2012; n = 281 isolates from 182 patients) was analyzed to identify chromosomal insertions of Tn4401, the transposon most frequently harboring blaKPC. Using a combination of short- and long-read sequencing, we confirmed five independent chromosomal integration events from 6/182 (3%) patients, corresponding to 15/281 (5%) isolates. Three patients had isolates identified by perirectal screening, and three had infections which were all successfully treated. When a single copy of blaKPC was in the chromosome, one or both of the phenotypic carbapenemase tests were negative. All chromosomally integrated blaKPC genes were from Klebsiella spp., predominantly K. pneumoniae clonal group 258 (CG258), even though these represented only a small proportion of the isolates. Integration occurred via IS15-ΔI-mediated transposition of a larger, composite region encompassing Tn4401 at one locus of chromosomal integration, seen in the same strain (K. pneumoniae ST340) in two patients. In summary, we identified five independent chromosomal integrations of blaKPC in a large outbreak, demonstrating that this is not a rare event. blaKPC was more frequently integrated into the chromosome of epidemic CG258 K. pneumoniae lineages (ST11, ST258, and ST340) and was more difficult to detect by routine phenotypic methods in this context. The presence of chromosomally integrated blaKPC within successful, globally disseminated K. pneumoniae strains therefore is likely underestimated. PMID:28031204

  18. The Clinical Isolate Pseudomonas aeruginosa MMA83 Carries Two Copies of the blaNDM-1 Gene in a Novel Genetic Context


    Jovčić, Branko; Lepsanović, Zorica; Begović, Jelena; Rakonjac, Bojan; Perovanović, Jelena; Topisirović, Ljubiša; Kojić, Milan


    The genetic context of the blaNDM-1 gene in the genome of Pseudomonas aeruginosa MMA83 was investigated. Sequencing of the cosmid selected for the blaNDM-1 gene revealed the presence of two blaNDM-1 copies in the genome of P. aeruginosa MMA83 in a unique genetic environment. Additionally, mating assays, DNA-DNA hybridization, and an S1 nuclease assay strongly suggest that the blaNDM-1 gene in P. aeruginosa MMA83 is chromosome borne.

  19. bla(KPC) RNA expression correlates with two transcriptional start sites but not always with gene copy number in four genera of Gram-negative pathogens. (United States)

    Roth, Amanda L; Kurpiel, Philip M; Lister, Philip D; Hanson, Nancy D


    Klebsiella pneumoniae carbapenemase (KPC)-producing organisms are therapeutically and diagnostically challenging. It is possible that bla(KPC) gene expression plays a role in the variability observed in clinical susceptibility testing. bla(KPC) transformants together with 10 clinical isolates representing four genera were evaluated for bla(KPC) copy number and gene expression and correlated with β-lactam MIC data. The data suggest that mechanisms other than gene copy number and expression of bla(KPC) contribute to variability in susceptibility when testing KPC-producing isolates.

  20. Characterization of a novel plasmid type and various genetic contexts of bla OXA-58 in Acinetobacter spp. from multiple cities in China.

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    Yiqi Fu

    Full Text Available BACKGROUND/OBJECTIVE: Several studies have described the epidemiological distribution of blaOXA-58-harboring Acinetobacter baumannii in China. However, there is limited data concerning the replicon types of blaOXA-58-carrying plasmids and the genetic context surrounding blaOXA-58 in Acinetobacter spp. in China. METHODOLOGY/PRINCIPAL FINDINGS: Twelve non-duplicated blaOXA-58-harboring Acinetobacter spp. isolates were collected from six hospitals in five different cities between 2005 and 2010. The molecular epidemiology of the isolates was carried out using PFGE and multilocus sequence typing. Carbapenemase-encoding genes and plasmid replicase genes were identified by PCR. The genetic location of blaOXA-58 was analyzed using S1-nuclease method. Plasmid conjugation and electrotransformation were performed to evaluate the transferability of blaOXA-58-harboring plasmids. The genetic structure surrounding blaOXA-58 was determined by cloning experiments. The twelve isolates included two Acinetobacter pittii isolates (belong to one pulsotype, three Acinetobacter nosocomialis isolates (belong to two pulsotypes and seven Acinetobacter baumannii isolates (belong to two pulsotypes/sequence types. A. baumannii ST91 was found to be a potential multidrug resistant risk clone carrying both blaOXA-58 and blaOXA-23. blaOXA-58 located on plasmids varied from ca. 52 kb to ca. 143 kb. All plasmids can be electrotransformed to A. baumannii recipient, but were untypeable by the current replicon typing scheme. A novel plasmid replicase named repAci10 was identified in blaOXA-58-harboring plasmids of two A. pittii isolates, three A. nosocomialis isolates and two A. baumannii isolates. Four kinds of genetic contexts of blaOXA-58 were identified. The transformants of plasmids with structure of IS6 family insertion sequence (ISOur1, IS1008 or IS15-ΔISAba3-like element-blaOXA-58 displayed carbapenem nonsusceptible, while others with structure of intact ISAba3-like element-bla

  1. The emerge of a new superbug gene blaNDM-1

    Institute of Scientific and Technical Information of China (English)

    Wang Kaiji


    @@ NDM-- 1 in detail: NDM-1, which is the abbreviation of 'New Delhi metallo-beta-lactamase', is a recently dis-covered enzyme that is produced by some gram-negative Enterobaeteriaceae such as E coil (Esehe-riehia toll) and Klebsiella pneumonia.It is named after 'New Delhi', which is the capital of India, be-cause the first patient who was diagnosed to be colo-nized by bacteria with blaNDM-1 gene had gone toa hospital in New Delhi for cosmetic surgery not long before he was diagnosed.

  2. Genetic environments of the transferable plasmid-mediated blaCTX-M-3 gene in Serratia marcescens isolates. (United States)

    Chu, Pei-Yu; Peng, Chien-Fang


    In this study, genetic environments of the transferable plasmid-mediated blaCTX-M-3 gene were characterized among 14 isolates of cefotaxime-resistant Serratia marcescens using PCR and BLAST DNA sequence analysis. A total of 3 types of genetic architectures in the regions surrounding this blaCTX-M-3 gene were identified. Type I architecture was characterized by the presence of a complete insertion sequence of tnpA-ISEcp1, identified as interrupting a reverse IS26 sequence in the upstream region of the blaCTX-M-3 gene. A reverse-directional orf477 fragment was located downstream of the blaCTX-M-3 gene, which was in the same direction of the mucA gene. A common region containing the orf513 element was located upstream of the mucA gene. Moreover, a copy of the 3'-CS2 element was located immediately upstream of the orf513 element. A novel complex class 1 integron was characterized by the presence of the dfrA19 gene, which was flanked by two copies of class 1 integrons. This is the first report to describe the dfrA19 gene within a novel complex class 1 integron in S. marcescens isolates from Taiwan. This novel complex class 1 integron structure was located distantly upstream of the blaCTX-M-3 gene.

  3. A putative multi-replicon plasmid co-harboring beta-lactamase genes blaKPC-2, blaCTX-M-14 and blaTEM-1 and trimethoprim resistance gene dfrA25 from a Klebsiella pneumoniae sequence type (ST) 11 strain in China (United States)

    Tang, Yu; Shen, Pinghua; Liang, Wei; Jin, Jialin; Jiang, Xiaofei


    The global emergence of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae poses a major public health threat requiring immediate and aggressive action. Some older generation antibiotics, such as trimethoprim, serve as alternatives for treatment of infections. Here, we determined the complete nucleotide sequence of plasmid pHS091147, which co-harbored the carbapenemase (blaKPC-2) and trimethoprim resistance genes (dfrA25) from a Klebsiella pneumoniae sequence type (ST) 11 clone recovered in Shanghai, China. pHS091147 had three replication genes, several plasmid-stability genes and an intact type IV secretion system gene cluster. Besides blaKPC-2 and dfrA25, pHS091147 carried several other resistance genes, including β-lactamase genes blaTEM-1 and blaCTX-M-14, sulphonamide resistance gene sul1, a quinolone resistance gene remnant (ΔqnrB2), and virulence associated gene iroN. Notably, the multidrug-resistance region was a chimeric structure composed of three subregions, which shared strong sequence homology with several plasmids previously assigned in Genbank. To our knowledge, this is the first report of the co-localization of blaKPC-2 and dfrA25 on a novel putative multi-replicon plasmid in a Klebsiella pneumoniae ST11 clone. PMID:28152085

  4. Virulence of Klebsiella pneumoniae isolates harboring bla KPC-2 carbapenemase gene in a Caenorhabditis elegans model.

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    Jean-Philippe Lavigne

    Full Text Available Klebsiella pneumoniae carbapenemase (KPC is a carbapenemase increasingly reported worldwide in Enterobacteriaceae. The aim of this study was to analyze the virulence of several KPC-2-producing K. pneumoniae isolates. The studied strains were (i five KPC-2 clinical strains from different geographical origins, belonging to different ST-types and possessing plasmids of different incompatibility groups; (ii seven transformants obtained after electroporation of either these natural KPC plasmids or a recombinant plasmid harboring only the bla KPC-2 gene into reference strains K. pneumoniae ATCC10031/CIP53153; and (iii five clinical strains cured of plasmids. The virulence of K. pneumoniae isolates was evaluated in the Caenorhabditis elegans model. The clinical KPC producers and transformants were significantly less virulent (LT50: 5.5 days than K. pneumoniae reference strain (LT50: 4.3 days (p<0.01. However, the worldwide spread KPC-2 positive K. pneumoniae ST258 strains and reference strains containing plasmids extracted from K. pneumoniae ST258 strains had a higher virulence than KPC-2 strains belonging to other ST types (LT50: 5 days vs. 6 days, p<0.01. The increased virulence observed in cured strains confirmed this trend. The bla KPC-2 gene itself was not associated to increased virulence.

  5. Emergence of Acinetobacter baumannii ST730 carrying the bla OXA-72 gene in Brazil (United States)

    Pagano, Mariana; Rozales, Franciéli P; Bertolini, Diego; Rocha, Lisiane; Sampaio, Jorge LM; Barth, Afonso L; Martins, Andreza F


    Over the last decade, Acinetobacter baumannii resistant to carbapenems has emerged in many medical centres and has been commonly associated with high morbimortality. In Brazil, this resistance is mainly attributed to the spread of OXA-23-producing clones and, to a lesser extent, to OXA-143-producing clones. Here, we describe, for the first time, two OXA-72-producing A. baumannii isolates in southern Brazil to a broad spectrum of antibiotics, except polymyxin B and tigecycline. Molecular typing by multilocus sequence typing (MLST) demonstrated that both OXA-72-producing isolates belong to a new sequence type (ST), ST730, which was recently identified in OXA-23-producing A. baumannii isolates in São Paulo, Brazil. We demonstrate that the two A. baumannii ST730 isolates carrying blaOXA-72share a common ancestral origin with the blaOXA-23producers in Brazil. This observation reinforces the importance of strain-typing methods in order to clarify the dynamics of the emergence of new clones in a geographic region. PMID:27653364

  6. The role of the genetic elements bla oxa and IS Aba 1 in the Acinetobacter calcoaceticus-Acinetobacter baumannii complex in carbapenem resistance in the hospital setting

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    Vanessa Cristine Kobs

    Full Text Available Abstract: INTRODUCTION: Members of the Acinetobacter genus are key pathogens that cause healthcare-associated infections, and they tend to spread and develop new antibiotic resistance mechanisms. Oxacillinases are primarily responsible for resistance to carbapenem antibiotics. Higher rates of carbapenem hydrolysis might be ascribed to insertion sequences, such as the ISAba1 sequence, near bla OXA genes. The present study examined the occurrence of the genetic elements bla OXA and ISAba1 and their relationship with susceptibility to carbapenems in clinical isolates of the Acinetobacter calcoaceticus-Acinetobacter baumannii complex. METHODS: Isolates identified over 6 consecutive years in a general hospital in Joinville, Southern Brazil, were evaluated. The investigation of 5 families of genes encoding oxacillinases and the ISAba1 sequence location relative to bla OXA genes was conducted using polymerase chain reaction. RESULTS: All isolates presented the bla OXA-51-like gene (n = 78, and 91% tested positive for the bla OXA-23-like gene (n = 71. The presence of ISAba1 was exclusively detected in isolates carrying the bla OXA-23-like gene. All isolates in which ISAba1 was found upstream of the bla OXA-23-like gene (n = 69 showed resistance to carbapenems, whereas the only isolate in which ISAba1 was not located near the bla OXA-23-like gene was susceptible to carbapenems. The ISAba1 sequence position of another bla OXA-23-like-positive isolate was inconclusive. The isolates exclusively carrying the bla OXA-51-like gene (n = 7 showed susceptibility to carbapenems. CONCLUSIONS: The presence of the ISAba1 sequence upstream of the bla OXA-23-like gene was strongly associated with carbapenem resistance in isolates of the A. calcoaceticus-A. baumannii complex in the hospital center studied.

  7. Molecular typing and genetic environment of the blaKPC gene in Chilean isolates of Klebsiella pneumoniae. (United States)

    Barría-Loaiza, Carla; Pincheira, Andrea; Quezada, Mario; Vera, Alejandra; Valenzuela, Pedro; Domínguez, Mariana; Lima, Celia A; Araya, Ingrid; Araya, Pamela; Prat, Soledad; Aguayo, Carolina; Fernández, Jorge; Hormazábal, Juan Carlos; Bello-Toledo, Helia; González-Rocha, Gerardo


    The aim of this work was to determine the genetic environment and transferability of blaKPC as well as the pulsotypes of KPC-producing Klebsiella pneumoniae strains isolated from clinical samples in Chilean hospitals. Seventeen strains, principally isolated in Santiago (the capital of Chile) during the years 2012 and 2013, were included. The genetic environment of blaKPC was elucidated by PCR mapping and sequencing. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Curing and conjugation experiments were performed with six strains of different sequence types (STs) and pulsotypes. Thirteen pulsotypes and six STs, mainly belonging to clonal complex 258, were found. In addition, seven strains belonged to a new ST assigned ST1161. The blaKPC sequence indicated that 16 strains had the KPC-2 variant; in only one strain (UC331) an amino acid change (R6P) was detected, corresponding to a new KPC variant designated KPC-24. Molecular characterisation of the blaKPC genetic environment revealed two distinct platforms, namely variant 1a and the Tn4401a isoform, with the first being the most common (11/17 strains). Mating experiments failed to produce transconjugants; however, loss of blaKPC was achieved by plasmid curing in all assayed strains. In conclusion, in Chilean strains of K. pneumoniae, blaKPC is primarily found associated with the variant 1a and is located in non-transferable plasmids. In addition, this study highlights the description of the new ST1161 and the new KPC-24 variant.

  8. Sequence and expression of Acinetobacter baumannii blaNDM-1 gene%鲍曼不动杆菌blaNDM-1基因序列分析及表达

    Institute of Scientific and Technical Information of China (English)

    陈硕; 冯书章; 邱少富; 夏力亮; 王中强; 刘军; 柳楠; 祝令伟; 孙洋; 宋宏彬


    目的 研究NDM-1鲍曼不动杆菌厦门分离株耐药性产生的分子机制.方法 Vitek32测定耐药谱.根据GenBank发表blaNDM-1基因序列设计合成引物,利用PCR技术扩增NDM-1鲍曼不动杆菌的blaNDM-1结构基因及其上下游调控序列片段,连接T载体,转化至大肠杆菌E.coli DH5α,序列测定并进行BLAST分析比对.测定始发菌株与重组菌株对美洛培南的最小抑菌浓度.结果 药敏试验结果 显示,该菌株对碳青霉烯类及β-内酰胺类抗生素耐药.NDM-1鲍曼不动杆菌厦门分离株blaNDM-1基因与HK-01同源性为100%;与KP-05-506相比,在blaNDM-1和trpF之间有24 bp的插入.美洛培南最小抑菌浓度测定结果 表明,重组菌株E.coli DH5α(pMD18-T::blaNDM-1)MIC值比始发菌株E.coli DH5α升高256倍.结论 获得blaNDM-1基因的大肠杆菌能够表达碳青霉烯酶,该基因是碳青霉烯类抗生素耐药性产生的分子基础,该基因具有跨种水平传播的可能.%The emergence of plasmid-mediated carbapenemases, such as NDM-1 in Enlerobacleriaceae is a major public health issue. The first NDM-1 producing AcineLobacLer baiunannii isolated in Xiamen was characterized. Antibiotic susceptibility was assessed with Vitek32. The A. Baiunannii earring NDM-1 was resistant to carbapenems and |3-lactam antibiotics· And remained susceptible to aminoglycosides and flluoroquinolones. Gene transfer to E. Coli recipient was investigated by using PCR and transformation. Sequence analysis of blaNDM-1 encoding the metallo-fHactamase indicated that the blaNDM-1 of NDM-1 A. Baiunannii was 100% homology with E. Coli HK-01 from Hong Kong. And there was a 24bp insert sequence between blaNDM-1 and LrpF when compared with K. Pneumoniae KP-05-506 from India. Minimum inhibitory concentration (MIC) of the recombination strain E. Coli DH5a (pMD18-T: blaNDM-1 ) was increased 256 times more than E. Coli DH5a to meropenem. The result suggests that the E. Coli acquired the blaNDM-1 could express

  9. First descriptions of blaKPC in Raoultella spp. (R. planticola and R. ornithinolytica): report from the SENTRY Antimicrobial Surveillance Program. (United States)

    Castanheira, Mariana; Deshpande, Lalitagauri M; DiPersio, Joseph R; Kang, Julia; Weinstein, Melvin P; Jones, Ronald N


    Two strains of Raoultella planticola and one of Raoultella ornithinolytica showing carbapenem resistance were recovered from patients hospitalized in New Jersey and Ohio. All patients had received previous antimicrobial treatment, including carbapenems. These strains harbored bla(KPC-2) and bla(KPC-3). Carbapenemase genes were embedded in isoforms of Tn4401 and were plasmidic and chromosomal in location.

  10. Identificación genotípica de β-lactamasas de espectro espectro extendido (BLEE (blaTEM y blaSHV en Escherichia coli uropatógena

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    Yeffersson Grandas Franco


    Full Text Available Introducción: Las infecciones de tracto urinario (ITU son consideradas un problema de salud pública a nivel mundial debido a su incidencia y morbilidad. Entre los agentes causales que se aíslan con mayor frecuencia, se encuentra E. coli, con una prevalencia que va desde 40% al 95%. Actualmente, la problemática de las ITU ha venido en aumento, debido a la aparición de resistencia bacteriana a agentes antimicrobianos, influenciado por la presión selectiva, la preexistencia de genes de resistencia y el uso indiscriminado de antibióticos. Objetivo: Identificar molecularmente β-lactamasas de espectro extendido (blaTEM y blaSHV, en E. coli uropatógena, aislada en pacientes ambulatorios que asisten a un laboratorio clínico de tercer nivel de complejidad. Materiales y métodos: Estudio descriptivo de corte transversal. En este trabajo se estudiaron 250 cepas de las cuales 120 eran presuntivas de producir β-lactamasas de acuerdo al método de Kirby-bauer que se realizó años anteriores por el semillero de Inmunidad e Infección. Los genes de interés se amplificaron mediante PCR. Se utilizó Klebsiella pneumoniae ATCC 700603 como control positivo. Una vez amplificado el gen se llevó a cabo el corrido electroforético en gel de agarosa donde el producto amplificado fue de 470 pb en el caso de blaSHV y de 1080 pb para blaTEM. Los fenotipos compatibles con producción de β-lactamasas se analizaron por medio de distribución de frecuencia usando el software WHONET 5,6. La distribución de frecuencia de los genes analizados se calculó usando el software MedCalc versión 15.2.2 (Bélgica – Software BBVA. Resultados: De las cepas analizadas, el 52,8% portadoras del gen blaTEM y el 2,8% del gen blaSHV-2. Se encontró co-existencia de los genes blaSHV-2 y blaTEM en el 1,68% del total de las cepas. De todas las cepas presuntivas de producir BLEE (n=120, 94 fueron productoras de BLEE, lo que nos indicaría que las 21 cepas restantes, implementan

  11. Genotypic and Antimicrobial Susceptibility of Carbapenem-Resistant Acinetobacter baumannii: Analysis of ISAba Elements and blaOXA-23-like Genes Including A New Variant

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    Abbas eBahador


    Full Text Available Carbapenem-resistant Acinetobacter baumannii (CR-AB causes serious nosocomial infections, especially in ICU wards of hospitals, worldwide. Expression of blaOXA genes is the chief mechanism of conferring carbapenem resistance among CR-AB. Although some blaOXA genes have been studied among CR-AB isolates from Iran, their blaOXA-23-like genes have not been investigated. We used a multiplex-PCR to detect Ambler class A, B, and D carbapenemases of 85 isolates, and determined that 34 harbored blaOXA-23-like genes. Amplified fragment length polymorphism (AFLP genotyping, followed by DNA sequencing of blaOXA-23-like amplicons of CR-AB from each AFLP group was used to characterize their blaOXA-23-like genes. We also assessed the antimicrobial susceptibility pattern of CR-AB isolates, and tested whether they harbored insertion sequences ISAba1 and ISAba4. Sequence comparison with reference strain A. baumannii (NCTC12156 revealed five types of mutations in blaOXA-23-like genes; including one novel variant and four mutants that were already reported from China and the USA. All of the blaOXA-23-like genes mutations were associated with increased minimum inhibitory concentrations (MICs against imipenem. ISAba1 and ISAba4 sequences were detected upstream of blaOXA-23 genes in 19% and 7% of isolates, respectively. The isolation of CR-AB with new blaOXA-23 mutations including some that have been reported from the USA and China highlights CR-AB pervasive distribution, which underscores the importance of concerted national and global efforts to control the spread of CR-AB isolates worldwide.

  12. Rapid discrimination of Acinetobacter baumannii international clone II lineage by pyrosequencing SNP analyses of bla(OXA-51-like) genes. (United States)

    Matsui, Mari; Suzuki, Satowa; Suzuki, Masato; Arakawa, Yoshichika; Shibayama, Keigo


    We found that Acinetobacter baumannii international clone II generally possesses unique GTA sequence at nucleotide positions 106-108 in the bla(OXA-51-like) genes. We exploited this to develop an easy and rapid method for discrimination of international clone II from other A. baumannii by employing pyrosequencing analyses of single nucleotide polymorphisms.

  13. Identification of Achromobacter xylosoxidans by detection of the bla(OXA-114-like) gene intrinsic in this species. (United States)

    Turton, Jane F; Mustafa, Nazim; Shah, Jayesh; Hampton, Catherine V; Pike, Rachel; Kenna, Dervla T


    Achromobacter xylosoxidans is an emerging pathogen among patients with cystic fibrosis. Here we describe a specific PCR for identification of this organism, based on detection of bla(OXA-114-like). Comparison of isolates by pulsed-field gel electrophoresis revealed evidence of cross-infection in some cases, but most patients harbored their own strain.

  14. blaCTX-M-I group extended spectrum beta lactamase-producing Salmonella typhi from hospitalized patients in Lagos, Nigeria

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    Akinyemi KO


    Full Text Available Kabiru O Akinyemi,1 Bamidele A Iwalokun,2 Olajide O Alafe,1 Sulaiman A Mudashiru,1 Christopher Fakorede,11Department of Microbiology, Lagos State University, Ojo, Lagos, Nigeria; 2Biochemistry and Nutrition Division, Nigerian Institute of Medical Research, Yaba, Lagos, NigeriaPurpose: The global spread of blaCTX-M-I extended-spectrum beta-lactamase (ESBL-producing Salmonella spp. remains a major threat to treatment and control. Evidence of emergence and spread of this marker are lacking in Nigeria. This study investigated blaCTX-M-I ESBL production among Salmonella isolates from hospitalized patients.Methods: Patients (158 total made up of two groups were evaluated. Group A was composed of 135 patients with persistent pyrexia and group B was composed of 23 gastroenteritis patients and their stool samples. Samples were cultured, and isolates were identified and were subjected to antibiotic susceptibility testing by standard methods. Isolates were further screened for ESBL production, blaCTX-M-I genes and transferability by double disk synergy test, plasmid extraction, polymerase chain reaction, and conjugation experiment.Results: Thirty-five (25.9% Salmonella isolates were identified from group A, of which 74.3% were S. typhi, 22.9% were S. paratyphi and two (5.7% were invasive non-typhoidal S. enteritidis. Nine Plasmodium falciparum infections were recorded, four of which were identified as co-infections with typhoidal Salmonella. Only two (8.7% S. enteritidis samples were obtained from group B (P>0.05. A total of 24 isolates were ESBL-positive, eliciting resistance to five to seven antibiotics, and were multiple-drug resistant. ESBL production due to the blaCTX-M-I gene cluster was detected in eleven (45.8% Salmonella isolates. Nine (81.8% of the eleven blaCTX-M-I ESBL producers were S. typhi and two (18.2% isolates were S. enteritidis. Four of nine S. typhi blaCTX-M-I ESBL-producing strains harbored 23 kb self-transmissible plasmid that was co

  15. Replicon typing of plasmids carrying blaCTX-M-15 among Enterobacteriaceae isolated at the environment, livestock and human interface. (United States)

    Zurfluh, Katrin; Glier, Melinda; Hächler, Herbert; Stephan, Roger


    One of the currently most important antibiotic resistance mechanisms in Enterobacteriaceae is based on the production of ESBL enzymes that inactivate β-lactam antibiotics including cephalosporins and monobactams by hydrolyzing their β-lactam ring. In humans, the most prevalent ESBL enzyme type is encoded by blaCTX-M-15. CTX-M-15 producing enterobacterial strains were also frequently isolated from environmental samples including surface water and freshwater fish. Plasmids, which can be grouped in different plasmid incompatibility types, play a key role in the horizontal spread of these multidrug resistance genes. The purpose of this study was to investigate the diversity of plasmids that carry blaCTX-M-15 genes among Enterobacteriaceae isolated at the environment, livestock and human interface. In total, 81 blaCTX-M-15-harboring isolates collected between 2009 and 2014 were tested for its ability to transfer blaCTX-M-15 by conjugation. These plasmids were further typed. Transfer of a single blaCTX-M-15-harboring plasmid was observed in 32 (39.5%) of the isolates. The most frequent replicon types detected among these plasmids are IncF-type plasmids (n=12) (mostly multi replicon plasmids with a combination of following replicons: IncFII, IncFIA and IncFIB), followed by IncI1 (n=8), IncK (n=3) and IncR (n=1). A noticeable number of plasmids (n=8) could not be assigned to any of the tested replicon types. Knowledge about the plasmid types circulating in bacterial populations is indispensable for understanding epidemiological dynamics and for establishing intervention strategies to stop further dissemination of particular plasmids.

  16. First Description of the Extended Spectrum-Beta-Lactamase Gene blaCTX-M-109 in Salmonella Grumpensis Strains Isolated from Neonatal Nosocomial Infections in Dakar, Senegal.

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    Amadou Diop

    Full Text Available Nosocomial infections are very common in African hospitals, particularly in neonatal units. These infections are most often caused by bacteria such as Escherichia coli, Klebsiella spp and Staphylococcus spp. Salmonella strains are rarely involved in nosocomial infections. Here, we report the first description of S. Grumpensis in neonatal infections in Senegal. Seventeen Salmonella strains were isolated from hospitalized infants' stool samples. The following resistance phenotype was described in strains: AMXRTICRCFR FOXRCFXRCTXRCAZRIMPSATMRNARNORRCIPRTMRGMRTERSXTR. All isolates were susceptible to imipenem, 15 out of 17 produced an extended spectrum ß-lactamase (ESBL. blaOXA-1, blaSHV-1, blaTEM-1, blaCTX-M1 genes were detected in strains 8, 13, 5 and 8, respectively. blaCTX-M1 sequencing revealed the presence of blaCTX-M-109. Thirteen of the 17 Salmonella Grumpensis strains were analyzed by PFGE. These 13 isolates belonged to a single pulsotype and were genotypically identical. This is the first report of neonatal S. Grumpensis infections in Senegal, and the first report of blaCTX-M-109 in the genus Salmonella.

  17. Chromosomal blaCTX-M-₁₅ associated with ISEcp1 in Proteus mirabilis and Morganella morganii isolated at the Military Hospital of Tunis, Tunisia. (United States)

    Mahrouki, Sihem; Belhadj, Omrane; Chihi, Hela; Mohamed, Ben Moussa; Celenza, Giuseppe; Amicosante, Gianfranco; Perilli, Mariagrazia


    This study investigated the genetic environment of bla(CTX-M) genes and associated resistance genes in seven Proteus mirabilis and six Morganella morganii extended spectrum β-lactamase (ESBL)-positive isolates. The isolates were recovered from hospitalized patients with respiratory or urinary tract infections at the Military Hospital of Tunis, Tunisia. Twenty-one of the 200 strains exhibited non-susceptibility to third generation cephalosporins and, among these strains, the double-disk synergy test confirmed the ESBL phenotype in 13 isolates. These ESBL producers were co-resistant to chloramphenicol, tetracycline and oflaxacin but remained susceptible to ertapenem (MIC<0.25 mg l(-1)). The presence and nature of bla(CTX-M-15), bla(CTX-M-8), bla(TEM-24), bla(TEM-1) and bla(TEM-2) genes was determined by PCR and sequencing. Chromosomal localization of the bla(CTX-M-15) gene was confirmed in all strains, with the exception of M. morganii isolate M-17991, by Southern-blot analysis performed either on chromosomal or plasmid DNA. M. morganii M-12012 and M. morganii M-6019 showed the same PFGE pattern, whereas the remaining CTX-M-15-producing isolates were unrelated. The presence of ISEcp1 was ascertained in CTX-M-15-producing isolates. A class 1 integron with different gene cassettes (dfrA1, orfC and aadB) was found in five P. mirabilis and six M. morganii isolates.

  18. Class 1 integrons in non-clonal multidrug-resistant Acinetobacter baumannii from Iran, description of the new blaIMP-55 allele in In1243. (United States)

    Azizi, Omid; Shakibaie, Mohammad Reza; Badmasti, Farzad; Modarresi, Farzan; Ramazanzadeh, Rashid; Mansouri, Shahla; Shahcheraghi, Fereshteh


    Infections and outbreaks caused by multidrug-resistant Acinetobacter baumannii (MDR-AB) are prevalent and have been reported worldwide over the past 20 or more years. Class 1 integron in MDR-AB plays an important role in the spread of antibiotic resistance in clinical settings. This study has been conducted to evaluate the detection of metallo-β-lactamase, characterization of class 1 integron and determination of clonal relatedness among A. baumannii hospital isolates. Sixty-five clinical isolates of MDR-AB were recovered from two Iranian hospital's intensive care units from February to August 2013. Integrase (intI1) and blaIMP genes were detected in 70.8 % (n=46/65) and 9.23 % (n=6/65) of the isolates using PCR assay, respectively. No other metallo-β-lactamase genes (blaVIM, blaSIM and blaNDM) were detected. PCR sequencing of integron gene cassette revealed the following arrays: blaOXA10-aacA4-blaIMP-55-cmlA5 (as a novel array was designated In1243), aacC1 and aadA1. Analysis of blaIMP gene revealed a new allele designated as blaIMP-55. Gene transfer experiment by conjugation showed the 36 kb conjugative plasmid harbouring In1243. The clonal assessment by repetitive extragenic palindromic PCR demonstrated a high-degree relatedness among the strains, but strains harbouring In1243 displayed a different repetitive extragenic palindromic PCR profile. In this study, we found that a novel class 1 integron (In1243) that encoded a new blaIMP allele resided on a transferable plasmid in non-clonal strains of MDR-AB.

  19. Dissemination of blaOXA-23 in Acinetobacter spp. in China: main roles of conjugative plasmid pAZJ221 and transposon Tn2009. (United States)

    Liu, Li-Lin; Ji, Shu-Juan; Ruan, Zhi; Fu, Ying; Fu, Yi-Qi; Wang, Yan-Fei; Yu, Yun-Song


    Production of the OXA-23 carbapenemase is the most common reason for the increasing carbapenem resistance in Acinetobacter spp. This study was conducted to reveal the genetic basis of blaOXA-23 dissemination in Acinetobacter spp. in China. A total of 63 carbapenem-resistant OXA-23-producing Acinetobacter sp. isolates, representing different backgrounds, were selected from 28 hospitals in 18 provinces for this study. Generally, two patterns of plasmids carrying blaOXA-23 were detected according to S1-nuclease pulsed-field gel electrophoresis and Southern blot hybridization. A ca. 78-kb plasmid, designated pAZJ221, was found in 23 Acinetobacter baumannii and three Acinetobacter nosocomialis isolates, while a novel ca. 50-kb plasmid was carried by only two other A. baumannii isolates. Three of these isolates had an additional copy of blaOXA-23 on the chromosome. Transformation of the two plasmids succeeded, but only pAZJ221 was conjugative. Plasmid pAZJ221 was sequenced completely and found to carry no previously known resistance genes except blaOXA-23. The blaOXA-23 gene of the remaining 35 isolates was chromosome borne. The blaOXA-23 genetic environments were correlated with Tn2009 in 57 isolates, Tn2008 in 5 isolates, and Tn2006 in 1 isolate. The MIC values for the carbapenems with these isolates were not significantly associated with the genomic locations or the copy numbers of blaOXA-23. Overall, these observations suggest that the plasmid pAZJ221 and Tn2009 have effectively contributed to the wide dissemination of blaOXA-23 in Acinetobacter spp. in China and that horizontal gene transfer may play an important role in dissemination of the blaOXA-23 gene.

  20. [Genetic Investigation of bla(CTX-M)-typing in Extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae from Clinical Specimens and Commercially Available Chicken Liver]. (United States)

    Kan, Miki; Shinomiya, Hiroto; Kitao, Takashi


    A genetic investigation consisting of the bla(CTX-M) typing was performed using 40 extended spectrum β-lactamase (ESBL)-producing Escherichia coli isolates from chicken liver and 43 ESBL-producing E. coli and 42 ESBL-producing Klebsiella pneumoniae isolates from patients. The types were determined using a sequence analysis. In 31 isolates in the bla(CTX-M-1) group, there were 13 with the bla(CTX-M-1) and all were from chicken liver. Nine E. coli isolates from chicken liver and one E. coli isolate from patients were found to be bla(CTX-M-55). In the bla(CTX-M-15), there were 6 E. coli isolates and one K. pneumoniae isolate from patients. All 39 isolates in the bla(CTX-M-2) group had the blac(CTX-M-2). Fifty-five isolates were found in the bla(CTX-M-9) group, the highest detection frequency, with 36 possessing bla(CTX-M-14) : 20 E. coli and 13 K. pneumoniae from patients and 3 E. coli from chicken liver. There were 17 bla(CTX-M-27) isolates, including 10 E. coli and 7 K. pneumoniae from patients. One bla(CTX-M-90) K. pneumoniae isolate and one bla(CTX-M-9) E. coli isolate were also obtained from patients. These results indicate that the E. coli isolates from chicken liver consist of bla(CTX-M-1), bla(CTX-M-2) and bla(CTX-M-55) ; the E. coli isolates from patients consist of bla(CTX-M-14) and bla(CTX-M-27) ; and the K. pneumoniae isolates from patients consist of bla(CTX-M-2), bla(CTX-M-14) and bla(CTX-M-27). Therefore, the bla(CTX-M) type differs in isolates from chicken liver and those from humans. These results suggest that it is unlikely that ESBL-producing E. coli from chicken liver are firmly established in the human intestinal tract.

  1. Genetic Environment of the blaKPC-2 Gene in a Klebsiella pneumoniae Isolate That May Have Been Imported to Russia from Southeast Asia. (United States)

    Ageevets, Vladimir; Sopova, Julia; Lazareva, Irina; Malakhova, Maya; Ilina, Elena; Kostryukova, Elena; Babenko, Vladislav; Carattoli, Alessandra; Lobzin, Yuri; Uskov, Alexander; Sidorenko, Sergey


    The nucleotide sequence of a blaKPC-2-harboring plasmid (pKPCAPSS) from Klebsiella pneumoniae ST273 isolated in Saint Petersburg, Russia, from a patient with history of recent travel to Vietnam is presented. This 127,970-bp plasmid possessed both IncFII and IncR replicons. blaKPC-2 was localized on a hypothetical mobile element. This element was flanked by 38-bp inverted Tn3 repeats and included a Tn3-specific transposase gene, macrolide resistance operon (mphA-mrx-mphR), and a fragment of blaTEM with unique polymorphisms.

  2. Complete sequence of the IncT-type plasmid pT-OXA-181 carrying the blaOXA-181 carbapenemase gene from Citrobacter freundii. (United States)

    Villa, Laura; Carattoli, Alessandra; Nordmann, Patrice; Carta, Claudio; Poirel, Laurent


    The gene encoding the carbapenemase OXA-181 (an OXA-48 variant) was identified from a Citrobacter freundii isolate coproducing NDM-1. The whole sequence of plasmid pT-OXA-181 bearing the blaOXA-181 gene was determined and revealed a 84-kb mobilizable but non-self-conjugative IncT-type plasmid. It totally differs from the 7.6-kb ColE-type and blaOXA-181-bearing plasmid recently identified in a Klebsiella pneumoniae isolate. However, in both plasmids, insertion sequence ISEcp1 might have played a role in acquisition of the blaOXA-181 gene.

  3. Double Copies of bla(KPC-3)::Tn4401a on an IncX3 Plasmid in Klebsiella pneumoniae Successful Clone ST512 from Italy. (United States)

    Fortini, Daniela; Villa, Laura; Feudi, Claudia; Pires, João; Bonura, Celestino; Mammina, Caterina; Endimiani, Andrea; Carattoli, Alessandra


    A carbapenem-resistant sequence type 512 (ST512) Klebsiella pneumoniae carbapenemase 3 (KPC-3)-producing K. pneumoniae strain showing a novel variant plasmid content was isolated in Palermo, Italy, in 2014. ST512 is a worldwide successful clone associated with the spread of bla(KPC) genes located on the IncFIIk pKpQIL plasmid. In our ST512 strain, the bla(KPC-3) gene was unusually located on an IncX3 plasmid, whose complete sequence was determined. Two copies of bla(KPC-3)::Tn4401a caused by intramolecular transposition events were detected in the plasmid.

  4. IncA/C Plasmid Carrying bla(NDM-1), bla(CMY-16), and fosA3 in a Salmonella enterica Serovar Corvallis Strain Isolated from a Migratory Wild Bird in Germany. (United States)

    Villa, L; Guerra, B; Schmoger, S; Fischer, J; Helmuth, R; Zong, Z; García-Fernández, A; Carattoli, A


    A Salmonella enterica serovar Corvallis strain was isolated from a wild bird in Germany. This strain carried the IncA/C2 pRH-1238 plasmid. Complete sequencing of the plasmid was performed, identifying the blaNDM-1, blaCMY-16, fosA3, sul1, sul2, strA, strB, aac(6')-Ib, aadA5, aphA6, tetA(A), mphA, floR, dfrA7, and merA genes, which confer clinically relevant resistance to most of the antimicrobial classes, including β-lactams with carbapenems, fosfomycin, aminoglycosides, co-trimoxazole, tetracyclines, and macrolides. The strain likely originated from the Asiatic region and was transferred to Germany through the Milvus migrans migratory route.

  5. Prevalence of ESBL phenotype,blaCTX-M-1,blaSHV andblaTEM genes among uropathogenicEscherichia coli isolates from 3 military hospitals of Tehran, Iran

    Institute of Scientific and Technical Information of China (English)

    Farshad Nojoomi; Abdolmajid Ghasemian


    Objective:To determine the extended-spectrum beta-lactamase (ESBL) production and prevalence ofblaCTX-M-1,blaSHV andblaTEM genes among uropathogenic Escherichia coli(UPEC) isolates from 3 military hospitals of Tehran during 2015–2016. Methods: One-hundred and eleven isolates were adopted. The antibiotic susceptibility testing was conducted according to Clinical and Laboratory Standards Institute guidelines. The combine disk was used for phenotypicESBL production. The ceftazidimeMIC was conducted with the micro-broth dilution test. ThePCR assay was used to detect theblaCTX-M-1,blaSHV and blaTEM genes. Results:In the broth microdilution method, 103 (92.7%) isolates showed minimal inhibitory concentration (MIC)≥1µg/mL, and also in the combined disk method, 89 (80.1% of all) wereESBL positive. On the other hand, among 91 ceftazidime resistant isolates, 86 (77.4% of all) wereESBLpositive. The difference between the two methods forESBL confirmation was not significant. The result ofMIC was similar to the disk diffusion method in the detection of phenotypicESBL production. AmongESBLproducer isolates, the prevalence ofblaCTX-M-1, blaSHV andblaTEM was 77.4% (n= 86), 47.4% (n= 53) and 2.4% (n= 2), respectively. These genes were amplified in a wide rangeMIC of ceftazidime. Conclusions:The prevalence of multi-drug resistantUPEC andESBL positive isolates was high in military hospitals. The majority ofUPEC isolates amplifiedblaCTX-M-I andblaSHV typeβ-lactamase genes. One-third of isolates were positive in presence of both these genes. There was no relation between ceftazidimeMIC and presence of beta-lactamase genes.

  6. High prevalence of blaOXA-23 in Acinetobacter spp. and detection of blaNDM-1 in A. soli in Cuba: report from National Surveillance Program (2010–2012) (United States)

    Quiñones, D.; Carvajal, I.; Perez, Y.; Hart, M.; Perez, J.; Garcia, S.; Salazar, D.; Ghosh, S.; Kawaguchiya, M.; Aung, M.S.; Kobayashi, N.


    As a first national surveillance of Acinetobacter in Cuba, a total of 500 Acinetobacter spp. isolates recovered from 30 hospitals between 2010 and 2012 were studied. Acinetobacter baumannii–calcoaceticus complex accounted for 96.4% of all the Acinetobacter isolates, while other species were detected at low frequency (A. junii 1.6%, A. lwoffii 1%, A. haemolyticus 0.8%, A. soli 0.2%). Resistance rates of isolates were 34–61% to third-generation cephalosporins, 49–50% to β-lactams/inhibitor combinations, 42–47% to aminoglycosides, 42–44% to carbapenems and 55% to ciprofloxacin. However, resistance rates to colistin, doxycycline, tetracycline and rifampin were less than 5%. Among carbapenem-resistant isolates, 75% harboured different blaOXA genes (OXA-23, 73%; OXA-24, 18%; OXA-58, 3%). The blaNDM-1 gene was identified in an A. soli strain, of which the species was confirmed by sequence analysis of 16S rRNA gene, rpoB, rpoB–rpoC and rpoL–rpoB intergenic spacer regions and gyrB. The sequences of blaNDM-1 and its surrounding genes were identical to those reported for plasmids of A. baumannii and A. lwoffi strains. This is the first report of blaNDM-1 in A. soli, together with a high prevalence of OXA-23 carbapenemase for carbapenem resistance in Acinetobacter spp. in Cuba. PMID:26236494

  7. High prevalence of blaOXA-23 in Acinetobacter spp. and detection of blaNDM-1 in A. soli in Cuba: report from National Surveillance Program (2010–2012

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    D. Quiñones


    Full Text Available As a first national surveillance of Acinetobacter in Cuba, a total of 500 Acinetobacter spp. isolates recovered from 30 hospitals between 2010 and 2012 were studied. Acinetobacter baumannii–calcoaceticus complex accounted for 96.4% of all the Acinetobacter isolates, while other species were detected at low frequency (A. junii 1.6%, A. lwoffii 1%, A. haemolyticus 0.8%, A. soli 0.2%. Resistance rates of isolates were 34–61% to third-generation cephalosporins, 49–50% to β-lactams/inhibitor combinations, 42–47% to aminoglycosides, 42–44% to carbapenems and 55% to ciprofloxacin. However, resistance rates to colistin, doxycycline, tetracycline and rifampin were less than 5%. Among carbapenem-resistant isolates, 75% harboured different blaOXA genes (OXA-23, 73%; OXA-24, 18%; OXA-58, 3%. The blaNDM-1 gene was identified in an A. soli strain, of which the species was confirmed by sequence analysis of 16S rRNA gene, rpoB, rpoB–rpoC and rpoL–rpoB intergenic spacer regions and gyrB. The sequences of blaNDM-1 and its surrounding genes were identical to those reported for plasmids of A. baumannii and A. lwoffi strains. This is the first report of blaNDM-1 in A. soli, together with a high prevalence of OXA-23 carbapenemase for carbapenem resistance in Acinetobacter spp. in Cuba.

  8. Characterization of IncA/C conjugative plasmid harboring bla TEM-52 and bla CTX-M-15 extended-spectrum β-lactamases in clinical isolates of Escherichia coli in Tunisia. (United States)

    Chouchani, C; El Salabi, A; Marrakchi, R; Ferchichi, L; Walsh, T R


    To characterize the extended-spectrum β-lactamases (ESBLs) as well as their genetic environment in different isolates of Escherichia coli from patients with repeated urinary tract infections, large multidrug resistance (MDR) plasmids have been found. Definitive evidence for the presence of an A/C incompatibility complex (IncA/C) plasmid in the MDR isolates was provided by the probing of plasmids extracted from the clinical isolates. Conjugation experiments showed that bla genes were transferred by conjugation from the ten E. coli clinical isolates to E. coli XL1-Blue recipient. A comparative restriction fragment length polymorphism (RFLP) analysis of these plasmids showed that they are genetically similar, while the overall similarity of these plasmids supports the likelihood of recent movements among these E. coli isolates. Polymerase chain reaction (PCR) amplification and sequencing of the amplicons showed that the IncA/C plasmids harbor two ESBLs, identified as TEM-52 and CTX-M-15. Analysis of the plasmid DNA surrounding the bla (CTX-M-15) gene in the clinical isolates under study revealed a partially truncated fragment of ISEcp1 tnpA transposase. This result indicates the variety of genetic events that have enabled associations between ISEcp1 sequences and bla (CTX-M-15) genes in these clinical isolates.

  9. Lysine N[superscript zeta]-Decarboxylation Switch and Activation of the [beta]-Lactam Sensor Domain of BlaR1 Protein of Methicillin-resistant Staphylococcus aureus

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    Borbulevych, Oleg; Kumarasiri, Malika; Wilson, Brian; Llarrull1, Leticia I.; Lee, Mijoon; Hesek, Dusan; Shi, Qicun; Peng, Jeffrey; Baker, Brian M.; Mobashery, Shahriar (Notre)


    The integral membrane protein BlaR1 of methicillin-resistant Staphylococcus aureus senses the presence of {beta}-lactam antibiotics in the milieu and transduces the information to the cytoplasm, where the biochemical events that unleash induction of antibiotic resistance mechanisms take place. We report herein by two-dimensional and three-dimensional NMR experiments of the sensor domain of BlaR1 in solution and by determination of an x-ray structure for the apo protein that Lys-392 of the antibiotic-binding site is posttranslationally modified by N{sup {zeta}}-carboxylation. Additional crystallographic and NMR data reveal that on acylation of Ser-389 by antibiotics, Lys-392 experiences N{sup {zeta}}-decarboxylation. This unique process, termed the lysine N{sup {zeta}}-decarboxylation switch, arrests the sensor domain in the activated ('on') state, necessary for signal transduction and all the subsequent biochemical processes. We present structural information on how this receptor activation process takes place, imparting longevity to the antibiotic-receptor complex that is needed for the induction of the antibiotic-resistant phenotype in methicillin-resistant S. aureus.

  10. The sudden dominance of blaCTX-M harbouring plasmids in Shigella spp. Circulating in Southern Vietnam.

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    Nhu Thi Khanh Nguyen

    Full Text Available BACKGROUND: Plasmid mediated antimicrobial resistance in the Enterobacteriaceae is a global problem. The rise of CTX-M class extended spectrum beta lactamases (ESBLs has been well documented in industrialized countries. Vietnam is representative of a typical transitional middle income country where the spectrum of infectious diseases combined with the spread of drug resistance is shifting and bringing new healthcare challenges. METHODOLOGY: We collected hospital admission data from the pediatric population attending the hospital for tropical diseases in Ho Chi Minh City with Shigella infections. Organisms were cultured from all enrolled patients and subjected to antimicrobial susceptibility testing. Those that were ESBL positive were subjected to further investigation. These investigations included PCR amplification for common ESBL genes, plasmid investigation, conjugation, microarray hybridization and DNA sequencing of a bla(CTX-M encoding plasmid. PRINCIPAL FINDINGS: We show that two different bla(CTX-M genes are circulating in this bacterial population in this location. Sequence of one of the ESBL plasmids shows that rather than the gene being integrated into a preexisting MDR plasmid, the bla(CTX-M gene is located on relatively simple conjugative plasmid. The sequenced plasmid (pEG356 carried the bla(CTX-M-24 gene on an ISEcp1 element and demonstrated considerable sequence homology with other IncFI plasmids. SIGNIFICANCE: The rapid dissemination, spread of antimicrobial resistance and changing population of Shigella spp. concurrent with economic growth are pertinent to many other countries undergoing similar development. Third generation cephalosporins are commonly used empiric antibiotics in Ho Chi Minh City. We recommend that these agents should not be considered for therapy of dysentery in this setting.

  11. Diverse Genetic Array of blaCTXM-15 in Escherichia coli: A Single-Center Study from India. (United States)

    Maurya, Anand Prakash; Mishra, Shweta; Talukdar, Anupam Das; Dhar Chanda, Debadatta; Chakravarty, Atanu; Bhattacharjee, Amitabha


    CTX-M-15 is a chief contributor for expanded-spectrum cephalosporin and monobactam resistance in India, complicating treatment options. In this study, we have investigated genetic context of CTX-M-15 in Escherichia coli and their transmission dynamics in a tertiary referral hospital of India. A total of 198 isolates were collected, of which 66 were harboring blaCTXM-15. Among them, 14 isolates were carrying a single CTX-M-15 gene and 52 were harboring multiple extended-spectrum β-lactamase genes along with blaCTX-M-15. The resistance gene was flanked by tnpA, ISEcp1, IS26, and ORF477 in 10 different arrangements. The resistance determinant was horizontally transferable through F, W, I1, and P Inc types of plasmids. Restriction mapping of plasmids showed a variable band pattern even within the same Inc types. Minimum inhibitory concentration was found above the breakpoint level against expanded-spectrum cephalosporins and monobactam while susceptible against carbapenems. blaCTX-M-15 was highly stable and sustained in the cell after 115 serial passages. In pulse-field gel electrophoresis, eight pulsotypes of E. coli were found to be responsible for the spread of blaCTX-M-15 in the tertiary referral center. We conclude that the presence of CTX-M-15 in the heterogeneous group of E. coli is highly alarming in terms of infection control and it may require regular monitoring, so as to formulate appropriate antibiotic policy to stop the spread of this resistance determinant.

  12. Draft Genome Sequence of a Colistin-Resistant Klebsiella pneumoniae Clinical Strain Carrying the blaNDM-1 Carbapenemase Gene (United States)

    Yao, Zhihong; Feng, Yu; Lin, Ji


    ABSTRACT Klebsiella pneumoniae strain WCHKP1845, recovered from the sputum of a patient with pneumonia, was resistant to colistin and carried the carbapenemase gene blaNDM-1. Here, we report its 5.4-Mb draft genome sequence, comprising 140 contigs with an average 57.33% G+C content. The genome contains 5,118 coding sequences and 88 tRNA genes. PMID:28209835

  13. Limited transmission of bla(CTX-M-9)-type-positive Escherichia coli between humans and poultry in Vietnam. (United States)

    Ueda, Shuhei; Ngan, Bui Thi Kim; Huong, Bui Thi Mai; Hirai, Itaru; Tuyen, Le Danh; Yamamoto, Yoshimasa


    We examined whether Escherichia coli isolates that produce CTX-M-9-type extended-spectrum β-lactamases (ESBL) are transferred between humans and chickens in a Vietnamese community. The phylogenetic group compositions, sequence types, antimicrobial resistance profiles, the prevalence of plasmid antibiotic resistance genes, and the plasmid replicon types generally differed between the human and chicken E. coli isolates. Our results suggest that transmission of the bla(CTX-M-9)-positive E. coli between humans and poultry was limited.

  14. Virulence of Klebsiella pneumoniae isolates harboring bla KPC-2 carbapenemase gene in a Caenorhabditis elegans model. (United States)

    Lavigne, Jean-Philippe; Cuzon, Gaelle; Combescure, Christophe; Bourg, Gisèle; Sotto, Albert; Nordmann, Patrice


    Klebsiella pneumoniae carbapenemase (KPC) is a carbapenemase increasingly reported worldwide in Enterobacteriaceae. The aim of this study was to analyze the virulence of several KPC-2-producing K. pneumoniae isolates. The studied strains were (i) five KPC-2 clinical strains from different geographical origins, belonging to different ST-types and possessing plasmids of different incompatibility groups; (ii) seven transformants obtained after electroporation of either these natural KPC plasmids or a recombinant plasmid harboring only the bla KPC-2 gene into reference strains K. pneumoniae ATCC10031/CIP53153; and (iii) five clinical strains cured of plasmids. The virulence of K. pneumoniae isolates was evaluated in the Caenorhabditis elegans model. The clinical KPC producers and transformants were significantly less virulent (LT50: 5.5 days) than K. pneumoniae reference strain (LT50: 4.3 days) (pKPC-2 positive K. pneumoniae ST258 strains and reference strains containing plasmids extracted from K. pneumoniae ST258 strains had a higher virulence than KPC-2 strains belonging to other ST types (LT50: 5 days vs. 6 days, pKPC-2 gene itself was not associated to increased virulence.

  15. Bacillus licheniformis BlaR1 L3 loop is a zinc metalloprotease activated by self-proteolysis.

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    Stéphanie Berzigotti

    Full Text Available In Bacillus licheniformis 749/I, BlaP β-lactamase is induced by the presence of a β-lactam antibiotic outside the cell. The first step in the induction mechanism is the detection of the antibiotic by the membrane-bound penicillin receptor BlaR1 that is composed of two functional domains: a carboxy-terminal domain exposed outside the cell, which acts as a penicillin sensor, and an amino-terminal domain anchored to the cytoplasmic membrane, which works as a transducer-transmitter. The acylation of BlaR1 sensor domain by the antibiotic generates an intramolecular signal that leads to the activation of the L3 cytoplasmic loop of the transmitter by a single-point cleavage. The exact mechanism of L3 activation and the nature of the secondary cytoplasmic signal launched by the activated transmitter remain unknown. However, these two events seem to be linked to the presence of a HEXXH zinc binding motif of neutral zinc metallopeptidases. By different experimental approaches, we demonstrated that the L3 loop binds zinc ion, belongs to Gluzincin metallopeptidase superfamily and is activated by self-proteolysis.

  16. Ultrastructural changes caused by polymyxin B and meropenem in multiresistant Klebsiella pneumoniae carrying blaKPC-2 gene. (United States)

    Scavuzzi, Alexsandra Maria Lima; Alves, Luiz Carlos; Veras, Dyana Leal; Brayner, Fábio André; Lopes, Ana Catarina Souza


    The ultrastructural alterations caused by polymyxin B and meropenem and by the association between polymyxin B and meropenem were investigated in two multiresistant isolates of Klebsiella pneumoniae (K3-A2 and K12-A2) carriers of blaKPC-2, coming from infection and colonization in patients in a public hospital in Recife, Brazil. The ultrastructural changes were detected by transmission electron microscopy and scanning. The susceptibility of the isolates to antimicrobials was tested by the disc diffusion method and microdilution in broth. The analysis by electron microscopy showed that the isolates presented morphological and ultrastructural cellular changes when subjected to a clinically relevant concentration of antimicrobials alone or in combination. When subjected to meropenem, they presented retraction of the cytoplasmic material, rupture of the cell wall and extravasation of the cytoplasmic content. When submitted to polymyxin B, the isolates showed condensation of the ribosomes, DNA clotting, cell wall thickening and the presence of membrane compartment. When subjected to polymyxin B and meropenem in combination, the isolates showed a higher intensity of the ultrastructural changes visualized. This is the first report of the ultrastructural changes caused by polymyxin B and meropenem in multiresistant isolates of K. pneumoniae carriers of the blaKPC-2 gene. It should be noted that even when the K. pneumoniae isolates were multiresistant carriers of the blaKPC-2 gene, they underwent important structural change owing to the action of polymyxin B and meropenem.

  17. Within-Host and Population Transmission of blaOXA-48 in K. pneumoniae and E. coli. (United States)

    Haverkate, Manon R; Dautzenberg, Mirjam J D; Ossewaarde, Tjaco J M; van der Zee, Anneke; den Hollander, Jan G; Troelstra, Annet; Bonten, Marc J M; Bootsma, Martin C J


    During a large hospital outbreak of OXA-48 producing bacteria, most K. pneumoniaeOXA-48 isolates were phenotypically resistant to meropenem or imipenem, whereas most E. coliOXA-48 isolates were phenotypically susceptible to these antibiotics. In the absence of molecular gene-detection E. coliOXA-48 could remain undetected, facilitating cross-transmission and horizontal gene transfer of blaOXA-48. Based on 868 longitudinal molecular microbiological screening results from patients carrying K. pneumoniaeOXA-48 (n = 24), E. coliOXA-48 (n = 17), or both (n = 40) and mathematical modelling we determined mean durations of colonisation (278 and 225 days for K. pneumoniaeOXA-48 and E. coliOXA-48, respectively), and horizontal gene transfer rates (0.0091/day from K. pneumoniae to E. coli and 0.0015/day vice versa). Based on these findings the maximum effect of horizontal gene transfer of blaOXA-48 originating from E. coliOXA-48 on the basic reproduction number (R0) is 1.9%, and it is, therefore, unlikely that phenotypically susceptible E. coliOXA-48 will contribute significantly to the spread of blaOXA-48.

  18. β-Lactamases Encoded by blaCTX-M Group I Genes as Determinants of Resistance of Esbl-Positive Enterobacteriaceae in European Soldiers in Tropical Mali. (United States)

    Hagen, Ralf Matthias; Hinz, Rebecca; Frickmann, Hagen


    ESBL (extended-spectrum-β-lactamase)-positive Enterobacteriaceae, which colonized European soldiers in tropical Western African Mali, were subjected to a molecular assessment of their resistance determinants. By doing so, a better insight into the locally endemic pattern of ESBL-associated β-lactamase genes was aspired. From a previous study on diarrhea in European soldiers on deployment in tropical Mali, 15 ESBL-positive Escherichia coli with demonstrated high clonal diversity and one positive Klebsiella pneumoniae were assessed. Polymerase chain reactions (PCRs) for blaTEM and blaSHV β-lactamase genes with subsequent sequencing for the discrimination of ESBL- and non-ESBL variants were performed, followed by four group-specific PCRs for blaCTX-M genes. Non-ESBL-associated blaTEM-1 was identified in six out of 15 (40%) E. coli strains, while 100% of the assessed strains were positive for group I blaCTX-M . Considering the known clonal diversity of the assessed strains, the striking restriction to one group of blaCTX-M genes accounting for the ESBL phenotypes of the isolates suggests little genetic exchange in the local setting. Under such circumstances of restricted numbers of locally endemic target genes, PCR-based screening approaches for ESBL colonization might be promising.

  19. blaCTX-M-15 carried by IncF-type plasmids is the dominant ESBL gene in Escherichia coli and Klebsiella pneumoniae at a hospital in Ghana. (United States)

    Agyekum, Alex; Fajardo-Lubián, Alicia; Ansong, Daniel; Partridge, Sally R; Agbenyega, Tsiri; Iredell, Jonathan R


    Escherichia coli and Klebsiella pneumoniae producing extended-spectrum β-lactamases (ESBLs) are among the most multidrug-resistant pathogens in hospitals and are spreading worldwide. Horizontal gene transfer and spread of high-risk clones are involved in ESBL dissemination. Investigation of the resistance phenotypes of 101 consecutive clinical E. coli (n=58) and K. pneumoniae (n=43) isolated at the Komfo Anokye Teaching Hospital in Ghana over 3 months revealed 63 (62%) with an ESBL phenotype. All 63 had a blaCTX-M gene, and sequence analysis showed that 62 of these were blaCTX-M-15. blaCTX-M-15 was linked to ISEcp1 and orf477Δ in all isolates, and most isolates also carried blaTEM, aac(3)-II, aacA4cr, and/or blaOXA-30 genes on IncF plasmids. XbaI/pulsed-field electrophoresis showed heterogeneity among isolates of both species, suggesting that blaCTX-M-15 dissemination is caused by horizontal gene transfer rather than clonal spread of these species in Ghana.

  20. Complete Sequence of a Novel IncR-F33:A–:B– Plasmid, pKP1034, Harboring fosA3, blaKPC-2, blaCTX-M-65, blaSHV-12, and rmtB from an Epidemic Klebsiella pneumoniae Sequence Type 11 Strain in China (United States)

    Xiang, Dai-Rong; Li, Jun-Jie; Sheng, Zi-Ke; Yu, Hai-Ying; Deng, Mei; Bi, Sheng; Hu, Fei-Shu; Chen, Wei; Xue, Xiao-Wei; Zhou, Zhi-Bo; Doi, Yohei; Li, Lan-Juan


    A high fosfomycin resistance rate was observed in Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) in our previous study, but little is known about its mechanisms. In this study, we explored the prevalence of plasmid-mediated fosfomycin resistance determinants among fosfomycin-resistant KPC-KP strains from a Chinese university hospital and determined the complete sequence of a novel fosA3-carrying plasmid isolated from an epidemic K. pneumoniae sequence type (ST) 11 strain. A total of 97 KPC-KP strains were studied, of which 57 (58.8%) were resistant to fosfomycin, including 44 (45.4%) harboring fosA3 and 1 harboring fosA. All fosA3-positive strains belonged to the dominant ST11-pulse type (PT) A clone according to multilocus sequence typing and pulsed-field gel electrophoresis, suggesting clonal dissemination. The fosA-positive isolate belonged to ST11-PTE. The fosA3-carrying plasmid pKP1034 is 136,848 bp in length and is not self-transmissible. It is a multireplicon plasmid belonging to IncR-F33:A−: B−. Besides fosA3, a variety of other resistance determinants, including blaKPC-2, rmtB, blaCTX-M-65, and blaSHV-12, are identified in pKP1034, which would allow for coselection of fosA3 by most β-lactams and/or aminoglycosides and facilitate its dissemination despite limited use of fosfomycin in China. Detailed comparisons with related plasmids revealed that pKP1034 is highly mosaic and might have evolved from alarming recombination of the blaKPC-2-carrying plasmid pKPC-LK30 from Taiwan and the epidemic fosA3-carrying plasmid pHN7A8 from mainland China. PMID:26666939

  1. ESBL, plasmidic AmpC, and associated quinolone resistance determinants in coliforms isolated from hospital effluent: first report of qnrB2, qnrB9, qnrB19, and blaCMY-4 in Algeria. (United States)

    Anssour, Lynda; Messai, Yamina; Derkaoui, Meriem; Alouache, Souhila; Estepa, Vanesa; Somalo, Sergio; Torres, Carmen; Bakour, Rabah


    The characterization of extended-spectrum beta-lactamases , plasmidic AmpC (pAmpC), and associated plasmid-mediated quinolone resistance (PMQR) determinants in cefotaxime-resistant coliforms isolated from hospital effluent in Algiers showed blaCTX-M genes in 89%, blaTEM-1 in 79·8%, and pAmpC genes (blaCIT) in 2·7% isolates. Association of ISEcp1B with blaCTX-M was found in all CTX-M+ isolates, and 97·2% harboured class 1 integrons. Sequencing showed blaCTX-M-15, blaCTX-M-3, and blaCMY-4 genes. blaCTX-M-3 and blaCTX-M-15 were located in Inc L/M conjugative plasmids. The PMQR determinants identified were qnrB1, qnrB2, qnrB9, qnrB19, qnrS2, and aac(6')-Ib-cr. qnrB2, qnrB9, qnrB19, and blaCMY-4 are described for the first time in Algeria and qnrB19 for the first time in non-clinical environments. This study highlights the major potential role of hospital effluents as providers of resistance genes to natural environments.

  2. Dispersal of Carbapenemase blaVIM-1 Gene Associated with Different Tn402 Variants, Mercury Transposons, and Conjugative Plasmids in Enterobacteriaceae and Pseudomonas aeruginosa▿ (United States)

    Tato, Marta; Coque, Teresa M.; Baquero, Fernando; Cantón, Rafael


    The emergence of blaVIM-1 within four different genetic platforms from distinct Enterobacteriaceae and Pseudomonas aeruginosa isolates in an area with a low prevalence of metallo-β-lactamase producers is reported. Forty-three VIM-1-producing isolates (including 19 Enterobacter cloacae, 2 Escherichia coli, and 2 P. aeruginosa isolates, 18 Klebsiella pneumoniae isolate, and 2 Klebsiella oxytoca isolate) recovered from 2005 to 2007 and corresponding to 15 pulsed-field gel electrophoresis types were studied. The Enterobacteriaceae isolates corresponded to a hospital outbreak, and the P. aeruginosa isolates were sporadically recovered. The genetic context of the integrons carrying blaVIM-1 (arbitrarily designated types A, B, C, and D) was characterized by PCR mapping based on known Tn402 and mercury transposons and further sequencing. Among Enterobacteriaceae isolates, blaVIM-1 was part of integrons located either in an In2-Tn402 element linked to Tn21 (type A; In110-blaVIM-1-aacA4-aadA1) or in a Tn402 transposon lacking the whole tni module [type B; In113-blaVIM-1-aacA4-dhfrII (also called dfrB1)-aadA1-catB2] and the transposon was associated with an IncHI2 or IncI1 plasmid, respectively. Among P. aeruginosa isolates, blaVIM-1 was part of a new gene cassette array located in a defective Tn402 transposon carrying either tniBΔ3 and tniA (type C; blaVIM-1-aadA1) or tniC and ΔtniQ (type D; blaVIM-1-aadB), and both Tn402 variants were associated with conjugative plasmids of 30 kb. The dissemination of blaVIM-1 was associated with different genetic structures and bacterial hosts, depicting a complex emergence and evolutionary network scenario in our facility, Ramón y Cajal University Hospital, Madrid, Spain. Knowledge of the complex epidemiology of blaVIM-1 is necessary to control this emerging threat. PMID:19901094

  3. Structural Variabilities in β-Lactamase (blaA of Different Biovars of Yersinia enterocolitica: Implications for β-Lactam Antibiotic and β-Lactamase Inhibitor Susceptibilities.

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    Neelja Singhal

    Full Text Available Yersiniosis caused by Yersinia enterocolitica has been reported from all continents. The bacterial species is divided into more than fifty serovars and six biovars viz. 1A, 1B, 2, 3, 4 and 5 which differ in geographical distribution, ecological niches and pathogenicity. Most Y.enterocolitica strains harbor chromosomal genes for two β-lactamases, blaA an Ambler class A penicillinase and blaB an Ambler class C inducible cephalosporinase. In the present study, susceptibility to b-lactam antibiotics and β-lactamase inhibitor was studied for Y. enterocolitica strains of biovars 1A, 1B, 2 and 4. We observed that β-lactamases were expressed differentially among strains of different biovars. To understand the molecular mechanisms underlying such differential expression, the sequences of genes and promoters of blaA were compared. Also, the variants of blaA present in different biovars were modeled and docked with amoxicillin and clavulanic acid. The mRNA secondary structures of blaA variants were also predicted in-silico. Our findings indicated that neither variations in the promoter regions, nor the secondary structures of mRNA contributed to higher/lower expression of blaA in different biovars. Analysis of H-bonding residues of blaA variants with amoxicillin and clavulanic acid revealed that if amino acid residues of a β-lactamase interacting with amoxicillin and the clavulanic acid were similar, clavulanic acid was effective in engaging the enzyme, accounting for a significant reduction in MIC of amoxicillin-clavulanate. This finding might aid in designing better β-lactamase inhibitors with improved efficiencies in future.

  4. Structural Variabilities in β-Lactamase (blaA) of Different Biovars of Yersinia enterocolitica: Implications for β-Lactam Antibiotic and β-Lactamase Inhibitor Susceptibilities. (United States)

    Singhal, Neelja; Srivastava, Abhishikha; Kumar, Manish; Virdi, Jugsharan Singh


    Yersiniosis caused by Yersinia enterocolitica has been reported from all continents. The bacterial species is divided into more than fifty serovars and six biovars viz. 1A, 1B, 2, 3, 4 and 5 which differ in geographical distribution, ecological niches and pathogenicity. Most Y.enterocolitica strains harbor chromosomal genes for two β-lactamases, blaA an Ambler class A penicillinase and blaB an Ambler class C inducible cephalosporinase. In the present study, susceptibility to b-lactam antibiotics and β-lactamase inhibitor was studied for Y. enterocolitica strains of biovars 1A, 1B, 2 and 4. We observed that β-lactamases were expressed differentially among strains of different biovars. To understand the molecular mechanisms underlying such differential expression, the sequences of genes and promoters of blaA were compared. Also, the variants of blaA present in different biovars were modeled and docked with amoxicillin and clavulanic acid. The mRNA secondary structures of blaA variants were also predicted in-silico. Our findings indicated that neither variations in the promoter regions, nor the secondary structures of mRNA contributed to higher/lower expression of blaA in different biovars. Analysis of H-bonding residues of blaA variants with amoxicillin and clavulanic acid revealed that if amino acid residues of a β-lactamase interacting with amoxicillin and the clavulanic acid were similar, clavulanic acid was effective in engaging the enzyme, accounting for a significant reduction in MIC of amoxicillin-clavulanate. This finding might aid in designing better β-lactamase inhibitors with improved efficiencies in future.

  5. Structural Variabilities in β-Lactamase (blaA) of Different Biovars of Yersinia enterocolitica: Implications for β-Lactam Antibiotic and β-Lactamase Inhibitor Susceptibilities (United States)

    Singhal, Neelja; Srivastava, Abhishikha; Kumar, Manish; Virdi, Jugsharan Singh


    Yersiniosis caused by Yersinia enterocolitica has been reported from all continents. The bacterial species is divided into more than fifty serovars and six biovars viz. 1A, 1B, 2, 3, 4 and 5 which differ in geographical distribution, ecological niches and pathogenicity. Most Y.enterocolitica strains harbor chromosomal genes for two β-lactamases, blaA an Ambler class A penicillinase and blaB an Ambler class C inducible cephalosporinase. In the present study, susceptibility to b-lactam antibiotics and β-lactamase inhibitor was studied for Y. enterocolitica strains of biovars 1A, 1B, 2 and 4. We observed that β-lactamases were expressed differentially among strains of different biovars. To understand the molecular mechanisms underlying such differential expression, the sequences of genes and promoters of blaA were compared. Also, the variants of blaA present in different biovars were modeled and docked with amoxicillin and clavulanic acid. The mRNA secondary structures of blaA variants were also predicted in-silico. Our findings indicated that neither variations in the promoter regions, nor the secondary structures of mRNA contributed to higher/lower expression of blaA in different biovars. Analysis of H-bonding residues of blaA variants with amoxicillin and clavulanic acid revealed that if amino acid residues of a β-lactamase interacting with amoxicillin and the clavulanic acid were similar, clavulanic acid was effective in engaging the enzyme, accounting for a significant reduction in MIC of amoxicillin-clavulanate. This finding might aid in designing better β-lactamase inhibitors with improved efficiencies in future. PMID:25919756

  6. Whole-animal imaging of bacterial infection using endoscopic excitation of β-lactamase (BlaC)-specific fluorogenic probe (United States)

    Nooshabadi, Fatemeh; Yang, Hee-Jeong; Cheng, Yunfeng; Xie, Hexin; Rao, Jianghong; Cirillo, Jeffrey D.; Maitland, Kristen C.


    Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains one of the most frequent causes of death worldwide. The slow growth rate of Mtb limits progress toward understanding tuberculosis including diagnosis of infections and evaluating therapeutic efficacy. Development of near-infrared (NIR) β-lactamase (BlaC)-specific fluorogenic substrate has made a significant breakthrough in the whole-animal imaging to detect Mtb infection. The reporter enzyme fluorescence (REF) system using a BlaC-specific fluorogenic substrate has improved the detection sensitivity in whole-animal optical imaging down to ~104 colony forming units (CFU) of bacteria, about 100-fold improvement over recombinant strains. However, improvement of detection sensitivity is strongly needed for clinical diagnosis of early stage infection at greater tissue depth. In order to improve detection sensitivity, we have integrated a fiber-based microendoscpe into a whole-animal imaging system to transmit the excitation light from the fiber bundle to the fluorescent target directly and measure fluorescent level using BlaC-specific REF substrate in the mouse lung. REF substrate, CNIR800, was delivered via aerosol route to the pulmonary infected mice with M. bovis BCG strain at 24 hours post-infection and groups of mice were imaged at 1-4 hours post-administration of the substrate using the integrated imaging system. In this study we evaluated the kinetics of CNIR800 substrate using REF technology using the integrated imaging system. Integration of these technologies has great promise for improved detection sensitivity allowing pre-clinical imaging for evaluation of new therapeutic agents.

  7. Emerging Carbapenem-Resistant Pseudomonas aeruginosa Isolates Carrying blaIMP Among Burn Patients in Isfahan, Iran (United States)

    Radan, Mohsen; Moniri, Rezvan; Khorshidi, Ahmad; Gilasi, Hamidreza; Norouzi, Zohreh; Beigi, Fahimeh; Dasteh Goli, Yasaman


    Background Metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa is a significant pathogen in burn patients. Objectives The aim of this study was to determine the prevalence of carbapenem-resistant P. aeruginosa isolates, including those resistant to imipenemase (IMP), in a burn unit in Isfahan, Iran. Patients and Methods One hundred and fifty P. aeruginosa isolates from burn patients were tested for antibiotic susceptibility by the disc diffusion method in accordance with CLSI guidelines. Production of MBL was identified with the EDTA disk method. DNA was purified from the MBL-positive isolates, and detection of the blaIMP gene was performed with PCR. Results Fifty-seven out of 150 (38%) isolates were multi-drug resistant (MDR), and 93 (62%) were extensively-drug resistant (XDR). Among all isolates, the resistance rate to ciprofloxacin, tobramycin, imipenem, meropenem, amikacin, ceftazidime, and cefepime was higher than 90%, while the resistance rates to piperacillin/tazobactam and aztreonam were 70.7% and 86%, respectively. Colistin and polymyxin B remained the most effective studied antibiotics. All of the imipenem-resistant P. aeruginosa isolates were MBL-positive, and 107 out of 144 (74.3%) of the MBL isolates were positive for the blaIMP gene. Conclusions The results of this study show that the rate of P. aeruginosa-caused burn wound infections was very high, and many of the isolates were resistant to three or more classes of antimicrobials. Such extensive resistance to antimicrobial classes is important because few treatment options remain for patients with burn wound infections. blaIMP-producing P. aeruginosa isolates are a rising threat in burn-care units, and should be controlled by conducting infection-control assessments.

  8. Promoter Deletions of Klebsiella pneumoniae Carbapenemase (KPC)-Encoding Genes (blaKPC-2) and Efflux Pump (AcrAB) on β-Lactam Susceptibility in KPC-Producing Enterobacteriaceae


    Seecoomar, Gomattie D.; Marmol, Brenda C.; Kwon, Dong H.


    Klebsiella pneumoniae carbapenemase (KPC)-encoding genes containing promoter-deletions (blaKPC-2a, blaKPC-2b, and blaKPC-2c) have disseminated in Enterobacteriaceae. The minimal inhibitory concentrations (MICs) to β-lactams in clinical KPC-producing Enterobacteriaceae are ranging from susceptible to high-level resistant resulting in diagnostic problems. In order to better understand the variability in β-lactam MICs among KPC-producing Enterobacteriaceae, three isoforms of blaKPC-2 gene were u...

  9. The effect of BLA GABAB receptors in anxiolytic-like effect and aversive memory deficit induced by ACPA

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    Katayoon Kangarlu Haghighi


    Full Text Available Background: As a psychoactive plant, Cannabis sativa (Marijuana is widely used throughout the world. Several investigations have indicated that administration of Marijuana affects various cognitive and non-cognitive behaviors. These include anxiety-like behaviors and learning and memory deficit. It has been shown that three main cannabinoid receptors [i.e. CB1, CB2 and CB3 are involved in cannabinoids’ functions. CB1 receptors are abundantly expressed in the central nervous system regions such as hippocampus, amygdala, cerebellum and the cortex. Therefore, the neuropsychological functions of endocannabinoids are thought to be more linked to CB1 receptors. Among other brain regions, CB1 is highly expressed in the amygdala which is an integral component of the limbic circuitry. The amygdala plays a major role in the control of emotional behavior, including conditioned fear and anxiety. In present study we examined the possible roles of basolateral amygdala (BLA GABAB receptors in arachydonilcyclopropylamide (ACPA-induced anxiolytic-like effect and aversive memory deficit in adult male mice. Methods: This experimental study was conducted from September 2013 to December 2014 in Institute for Studies in Theoretical Physics and Mathematics, School of Cognitive Sciences, Tehran and Male albino NMRI mice (Pasture Institute, Iran, weighting 27-30 g, were used. Bilateral guide-cannulae were implanted to allow intra BLA microinjection of the drugs. We used Elevated Plus Maze (EPM to examine memory and anxiety behavior (test-retest protocol. ACPA administrate intra-peritoneal and GABAB agonist and antagonist administrated intra-amygdala. Results: Data showed that pre-test treatment with ACPA induced anxiolytic-like and aversive memory deficit The results revealed that pre-test intra-BLA infusion of baclofen (GABAB receptor agonist impaired the aversive memory while phaclofen (GABAB receptor antagonist improved it. Interestingly, pretreatment with a sub

  10. Structures of Two Major Allergens, Bla g 4 and Per a 4, From Cockroaches and Their IgE Binding Epitopes

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Y.; Chan, S; Ong, T; Yit, L; Tiong, Y; Chew, F; Sivaraman, J; Mok, Y


    Inhalant allergens from cockroaches are an important cause of asthma to millions of individuals worldwide. Here we report for the first time the structures of two major cockroach allergens, Bla g 4 and Per a 4, that adopt a typical lipocalin fold but with distinct structural features as compared with other known lipocalin allergens. Both Bla g 4 and Per a 4 contain two long-range disulfide bonds linking the N and C termini to a beta-barrel. The C-terminal helix of Bla g 4 is bent and greatly extended toward the N terminus. Bla g 4 is found to be a monomer, whereas Per a 4 exists as a dimer in solution with a novel dimeric interface involving residues from loops at the top and bottom of the beta-barrel. Putative ligand binding sites of both allergens are determined by docking of the juvenile hormone III inside the beta-barrel and found to interact with the ligand using non-conserved residues. Bla g 4 and Per a 4 are found to be cross-reactive in sera IgE binding, at least in the Singaporean Chinese population tested. A major IgE binding epitope unique to Per a 4 is found on the loops at the bottom of the beta-barrel that may aid the development of hypoallergens for immunotherapy.

  11. Theoretical Studies on the First Hyperpolarizabilities of One-dimensional Donor-bridge-acceptor Chromophores and New Applications of BLA in Determining Molecular First Hyperpolarizabilities

    Institute of Scientific and Technical Information of China (English)


    We present a quantum-chemical analysis of the relationship between the bond length alteration (BLA) and the static first hyperpolarizability of a series of one-dimensional (ID)chromophores with donor-bridge-acceptor (D-B-A) structures.The calculated results show that the parameter BLA can be considered as an indicator to evaluate the molecular first hyper-polarizability.Along the direction of molecular ground-state dipole moments, the evolutions of BLA can be classified into three categories: the first is a non-monotonic line, which represents most chromophores; the second is monotonic increasing; and the third, contrarily, is monotonic decreasing.On the whole, the first hyperpolarizabilities of these studied chromophores are the mortotonic functions of BLA along the direction of dipole moments.Therefore, the first hyper-polarizability of these 1D chromophores can be preliminarily evaluated in terms of the deve-lopment of BLA without a rigorous computation.In other words, one can roughly estimate the relative magnitude of the first hyperpolarizability according to the optimized geometry.

  12. 中巴资源卫星影像HR数据在煤矿矿区地面塌陷调查中的应用%Application of CBERS HR Image Data in Investigation of Surface Collapse in Coal Mine Zone

    Institute of Scientific and Technical Information of China (English)

    陈文平; 范英霞; 韩小明; 薛磊; 李少贞


    We apply, for the first time, the CBERS HR image data whose independent intellectual property rights are owned by China to investigate the surface collapse of coal mine zone through remote sensing technique. A problem which grows serious over time is coal mine zone' s surface collapse which features itself by its growing area and both its gradual and sudden change. It is difficult to deter- mine the boundary of the collapse zone and adapt to the development of the problem via conventional station observation. In this paper, we construct a remote sensing image lettering and interpreting system to interpret and delineate the boundary of collapse zones, collect relevant data and support the environmental protection of the region via human computer interaction using Liudaowan - Tieehanggou coal mine zone' s CBERS satellite HR image based on known fundamental features of the collapse zone as a case study.%首次应用具有我国自主知识产权的中巴资源卫星影像数据对煤矿矿区采煤地面塌陷进行遥感调查研究。煤矿采空区地面塌陷随着时间日趋严重,面积不断扩大,兼有渐变和突变的特点,用常规方法定点观测难以适应其发展,确定其边界分布非常困难。文章应用中巴资源卫星HR高分辨率影像数据,以六道湾一铁厂沟煤矿矿区为例,通过已知塌陷区的基本特点,建立塌陷区的遥感影像地物解译标志体系,通过人机交互遥感影像解译,圈定地面塌陷的边界并获得塌陷区的有关数据,为该地区环境地质灾害治理提供依据。

  13. Characterization of phenotypically metallo-β-lactamase positive Pseudomonas aeruginosa human isolates from Himachal Pradesh for MBL genes (blaVIM-2 and blaIMP-1, integrase gene class 1, 2, 3 (int1, int2 and int3 and sulphonamide resistance gene (sul1

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    Ruchi Chauhan


    Full Text Available Background & objectives: The present study highlights the occurrence of MBL gene (blaVIM-2, integron class 1 (int1 and sulphonamide resistance (sul1 genes in P. aeruginosa isolates recovered from patients of Shimla region of India. Methods: P. aeruginosa isolates detected positive for MBL by Combined Disc and Ezy MIC tests were characterized by PCR amplification of segments of blaIMP-1 and blaVIM-2, integrase genes encoding integron classes int1, int2 and int3, and sul1 gene. The nucleotide sequence homologies with the published sequences of Pseudomonas spp and other gram-negative bacilli were determined. Results: All the confirmed isolates of P. aeruginosa were further subjected to nucleotide sequencing of 16SrRNA amplicons. MBL gene (blaVIM-2 was amplified in six out of 27 MBL positive isolates, int1 gene in eleven and sul1 gene in 14 MBL positive isolates .Only one isolate Pa138 carried both blaVIM-2 and int1 genes. The specificity was established by nucleotide sequencing of the amplicons. Interpretation & Conclusion: The occurrence of blaVIM-2, int1 and sul1 genes has been reported in the P. aeruginosa isolates of Shimla region of Himachal Pradesh. The studies might be useful to the clinicians for selecting suitable antibiotic for treating and controlling P. aeruginosa infections in this region.

  14. Identifying ionic interactions within a membrane using BLaTM, a genetic tool to measure homo- and heterotypic transmembrane helix-helix interactions (United States)

    Schanzenbach, Christoph; Schmidt, Fabian C.; Breckner, Patrick; Teese, Mark G.; Langosch, Dieter


    The assembly of integral membrane protein complexes is frequently supported by transmembrane domain (TMD) interactions. Here, we present the BLaTM assay that measures homotypic as well as heterotypic TMD-TMD interactions in a bacterial membrane. The system is based on complementation of β-lactamase fragments genetically fused to interacting TMDs, which confers ampicillin resistance to expressing cells. We validated BLaTM by showing that the assay faithfully reports known sequence-specific interactions of both types. In a practical application, we used BLaTM to screen a focussed combinatorial library for heterotypic interactions driven by electrostatic forces. The results reveal novel patterns of ionizable amino acids within the isolated TMD pairs. Those patterns indicate that formation of heterotypic TMD pairs is most efficiently supported by closely spaced ionizable residues of opposite charge. In addition, TMD heteromerization can apparently be driven by hydrogen bonding between basic or between acidic residues. PMID:28266525

  15. The molecular phenomena of the blaZ genes forming betalactamase enzymes structure in Staphylococcus aureus resistant to beta-lactam antibiotics (ampicillin

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    Mieke Satari


    Full Text Available Background: Nowadays, infectious disease still an important problem. One of the bacteria causing infectious diseases is Staphylococcus aureus (S. aureus. In the effort to deal with infections caused by S. aureus, beta-lactam antibiotics, such as ampicillin, are used. In fact, it is unfortunately known that many of S. aureus bacteria are resistant to this group of antibiotics. Because of nucleotide base changes in the structure of the genes blaZ which encode beta-lactamase enzymes in S. aureus. Purpose: The objective of this study was to analyze the nucleotide base changes in the structure of the genes blaZ forming beta-lactamase enzymes in S. aureus resistant to ampicillin based on molecular point of view. Methods: Molecular examinations was conducted by isolating the genes, forming beta-lactamase enzyme, which length was 845bp, from 7 isolates of S. aureus resistant to ampicillin by using PCR technique. The results of blaZ amplification were then subjected to homology by using Tn 552 of S. aureus obtained from bank of genes. Results: Based on the result of the homology, it was found that there was a change in purine base TG, which was a pyrimidine base at the -37 position of the initial codon of blaZ. This change, however, did not affect the strength of the promoter since the number of A and T is still more than the number of G and C. In the structure of the blaZ gene there was even no mutation or deletion or nucleotide base substitution found, so it would not affect the effectiveness of beta-lactamase enzyme. Conclusion: It can be concluded that the resistance of S. aureus towards ampicillin was not caused by nucleotide base deletion/substation. It is suspected that there were other causes leading to the resistance, including the overproduction of beta-lactamase enzyme of the blaZ gene, causing the degradation of beta-lactam antibiotics.Latar belakang: Penyakit infeksi sampai saat ini masih merupakan masalah. Salah satu bakteri penyebab

  16. Persistence of Multidrug-Resistant Acinetobacter baumannii Isolates Harboring blaOXA-23 and bap for 5 Years. (United States)

    Sung, Ji Youn; Koo, Sun Hoe; Kim, Semi; Kwon, Gye Cheol


    The emergence and dissemination of carbapenemase-producing Acinetobacter baumannii isolates have been reported worldwide, and A. baumannii isolates harboring blaOXA-23 are often resistant to various antimicrobial agents. Antimicrobial resistance can be particularly strong for biofilm-forming A. baumannii isolates. We investigated the genetic basis for carbapenem resistance and biofilm-forming ability of multidrug-resistant (MDR) clinical isolates. Ninety-two MDR A. baumannii isolates were collected from one university hospital located in the Chungcheong area of Korea over a 5-year period. Multiplex PCR and DNA sequencing were performed to characterize carbapenemase and bap genes. Clonal characteristics were analyzed using REP-PCR. In addition, imaging and quantification of biofilms were performed using a crystal violet assay. All 92 MDR A. baumannii isolates involved in our study contained the blaOXA-23 and bap genes. The average absorbance of biomass in Bap-producing strains was much greater than that in non-Bap-producing strains. In our study, only three REP-PCR types were found, and the isolates showing type A or type B were found more than 60 times among unique patients during the 5 years of surveillance. These results suggest that the isolates have persisted and colonized for 5 years, and biofilm formation ability has been responsible for their persistence and colonization.

  17. Promoter deletions of Klebsiella pneumoniae carbapenemase (KPC)-encoding genes (blaKPC -2) and efflux pump (AcrAB) on β-lactam susceptibility in KPC-producing Enterobacteriaceae. (United States)

    Seecoomar, Gomattie D; Marmol, Brenda C; Kwon, Dong H


    Klebsiella pneumoniae carbapenemase (KPC)-encoding genes containing promoter-deletions (bla(KPC-2a), bla(KPC-2b), and bla(KPC-2c) have disseminated in Enterobacteriaceae. The minimal inhibitory concentrations (MICs) to β-lactams in clinical KPC-producing Enterobacteriaceae range from susceptible to high-level resistant, resulting in diagnostic problems. To better understand the variability in β-lactam MICs among KPC-producing Enterobacteriaceae, three isoforms of bla(KPC-2) gene were used to transform Escherichia coli W4573 and its deletion mutant of an efflux pump (AcrAB) to examine the effects on β-lactam susceptibility. MICs to β-lactams in E. coli W4573 and its acrAB mutant strain increased 1- to 500-fold (MIC from 0.125 to 64 μg mL(-1) of aztreonam) in the bla(KPC-2a), bla(KPC-2b), and bla(KPC-2c) transformants compared with the cloning vector alone. However, transformants of the acrAB mutant strain remained susceptible to all β-lactams tested except for aztreonam and carbenicillin. Levels of the three promoters' length and carbapenemase activities in the transformants harboring the bla(KPC-2a), bla(KPC-2b), and bla(KPC-2c) were correlated to the levels of β-lactam MICs in both E. coli W4573 and its mutant of an efflux pump (AcrAB). Overall, these results suggest that promoter-deletions of bla(KPC-2) gene and AcrAB may be associated with the variability in β-lactam MICs in KPC-producing Enterobacteriaceae.

  18. Emergence of blaCTX-M-15 Gene and Its Transferability in Enterobacter spp. Isolated From the Hospitals of Tehran, Iran

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    Salimian Rizi


    Full Text Available Background Enterobacter spp. is increasingly recognized as an important nosocomial pathogen and implicated in many episodes of hospital acquired infections. Objectives The current study aimed to describe distribution and transferability of blaCTX-M-15 gene, and the antibiotic susceptibility pattern in the clinical isolates of Enterobacter spp. Materials and Methods A total of 110 Enterobacter isolates were collected from five hospitals in Tehran, Iran from May 2012 to April 2013. Enterobacter species were identified by API 20E system. Antibacterial susceptibility was determined by disk diffusion method, and extended spectrum beta lactamase (ESBL production was confirmed by combined disk method. The blaCTX-M-15 gene was identified by PCR with specific primers. The transferability of the blaCTX-M-15was tested by conjugation with broth matting method. Results The prevalence of Enterobacter species was E. cloacae (78.2 %, E. aerogenes (6.13 % and E. sakazakii (8.2%. They were from different clinical sources. Maximal resistance in Enterobacter isolates was noticed against Augmentin®, trimethoprim - sulfamethoxazole and cefoxitin 75.5%, 64.5%, and 59.1%, respectively. Fourteen isolates, showed ESBL phenotype. The blaCTX-M-15 gene frequency in Enterobacter isolates was 11.8%. Three conjugative plasmids containing blaCTX-M-15 were found in one Enterobacter isolate. Conclusions It was the first report on the blaCTX-M-15 gene emergence in clinical Enterobacter spp. in Iran. The current study demonstrated the predominant presence of the gene encoding CTX-M-15 among ESBL producing Enterobacter spp. commonly with a large plasmid, in the setting.

  19. Complete sequencing of the bla(NDM-1-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens.

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    Tsuyoshi Sekizuka

    Full Text Available The complete sequence of the plasmid pNDM-1_Dok01 carrying New Delhi metallo-β-lactamase (NDM-1 was determined by whole genome shotgun sequencing using Escherichia coli strain NDM-1_Dok01 (multilocus sequence typing type: ST38 and the transconjugant E. coli DH10B. The plasmid is an IncA/C incompatibility type composed of 225 predicted coding sequences in 195.5 kb and partially shares a sequence with bla(CMY-2-positive IncA/C plasmids such as E. coli AR060302 pAR060302 (166.5 kb and Salmonella enterica serovar Newport pSN254 (176.4 kb. The bla(NDM-1 gene in pNDM-1_Dok01 is terminally flanked by two IS903 elements that are distinct from those of the other characterized NDM-1 plasmids, suggesting that the bla(NDM-1 gene has been broadly transposed, together with various mobile elements, as a cassette gene. The chaperonin groES and groEL genes were identified in the bla(NDM-1-related composite transposon, and phylogenetic analysis and guanine-cytosine content (GC percentage showed similarities to the homologs of plant pathogens such as Pseudoxanthomonas and Xanthomonas spp., implying that plant pathogens are the potential source of the bla(NDM-1 gene. The complete sequence of pNDM-1_Dok01 suggests that the bla(NDM-1 gene was acquired by a novel composite transposon on an extensively disseminated IncA/C plasmid and transferred to the E. coli ST38 isolate.

  20. Complete sequencing of the bla(NDM-1)-positive IncA/C plasmid from Escherichia coli ST38 isolate suggests a possible origin from plant pathogens. (United States)

    Sekizuka, Tsuyoshi; Matsui, Mari; Yamane, Kunikazu; Takeuchi, Fumihiko; Ohnishi, Makoto; Hishinuma, Akira; Arakawa, Yoshichika; Kuroda, Makoto


    The complete sequence of the plasmid pNDM-1_Dok01 carrying New Delhi metallo-β-lactamase (NDM-1) was determined by whole genome shotgun sequencing using Escherichia coli strain NDM-1_Dok01 (multilocus sequence typing type: ST38) and the transconjugant E. coli DH10B. The plasmid is an IncA/C incompatibility type composed of 225 predicted coding sequences in 195.5 kb and partially shares a sequence with bla(CMY-2)-positive IncA/C plasmids such as E. coli AR060302 pAR060302 (166.5 kb) and Salmonella enterica serovar Newport pSN254 (176.4 kb). The bla(NDM-1) gene in pNDM-1_Dok01 is terminally flanked by two IS903 elements that are distinct from those of the other characterized NDM-1 plasmids, suggesting that the bla(NDM-1) gene has been broadly transposed, together with various mobile elements, as a cassette gene. The chaperonin groES and groEL genes were identified in the bla(NDM-1)-related composite transposon, and phylogenetic analysis and guanine-cytosine content (GC) percentage showed similarities to the homologs of plant pathogens such as Pseudoxanthomonas and Xanthomonas spp., implying that plant pathogens are the potential source of the bla(NDM-1) gene. The complete sequence of pNDM-1_Dok01 suggests that the bla(NDM-1) gene was acquired by a novel composite transposon on an extensively disseminated IncA/C plasmid and transferred to the E. coli ST38 isolate.

  1. Influence of agricultural practice on mobile bla genes: IncI1-bearing CTX-M, SHV, CMY and TEM in Escherichia coli from intensive farming soils. (United States)

    Jones-Dias, Daniela; Manageiro, Vera; Caniça, Manuela


    Many calls have been made to address antibiotic resistance in an environmental perspective. With this study, we showed the widespread presence of high-level antibiotic resistant isolates on a collection of non-susceptible Gram-negative bacteria (n = 232) recovered from soils. Bacteria were selected using amoxicillin, cefotaxime and imipenem, from sites representing different agricultural practices (extensive, intensive and organic). Striking levels of non-susceptibility were noticed in intensive soils for norfloxacin (74%), streptomycin (50.7%) and tetracycline (46.6%); indeed, the exposure to intensive agricultural practices constituted a risk factor for non-susceptibility to many antibiotics, multidrug resistance and production of extended-spectrum β-lactamases (ESBL). Analyses of non-susceptibility highlighted that environmental and clinical bacteria from the same species might not share the same intrinsic resistance patterns, raising concerns for therapy choices in environment-borne infections. The multiple sequence-type IncI1-driven spread of penicillinases (blaTEM-1, blaTEM-135), ESBL (blaSHV-12 and blaCTX-M-1) and plasmid-mediated AmpC β-lactamases (blaCMY-2), produced by isolates that share their molecular features with isolates from humans and animals, suggests contamination of agricultural soils. This is also the first appearance of IncI1/ST28-harbouring blaCTX-M-1, which should be monitored to prevent their establishment as successfully dispersed plasmids. This research may help disclose paths of contamination by mobile antibiotic resistance determinants and the risks for their dissemination.

  2. Association of the Extended-Spectrum β-Lactamase Gene blaTLA-1 with a Novel ISCR Element, ISCR20▿ (United States)

    Berçot, Beatrice; Poirel, Laurent; Silva-Sanchez, Jesus; Nordmann, Patrice


    The blaTLA-1 gene encoding an extended-spectrum β-lactamase was identified in 11 enterobacterial isolates from Mexico City, Mexico. This gene was located on different plasmids and plasmid types with different sizes and incompatibility groups. It was associated with a novel insertion sequence, ISCR20, encoding a putative transposase that shared only 20% amino acid identity with the most closely related transposase of ISCR1. The ISCR20 element provided specific promoter sequences for expression of the blaTLA-1 gene. PMID:20585120

  3. Probable Interspecies Transfer of the bla(VIM-4) Gene between Enterobacter cloacae and Klebsiella pneumoniae in a Single Infant Patient. (United States)

    Piekarska, Katarzyna; Zacharczuk, Katarzyna; Rzeczkowska, Magdalena; Wołkowicz, Tomasz; Januszkiewicz, Aleksandra; Podsiadły, Edyta; Demkow, Urszula; Gierczyński, Rafał


    We report the interspecies transfer of the bla(VLM-4) gene in MBL-producing Enterobacter cloacae and Klebsiella pneumoniae isolates from a newborn patient who had received meropenem therapy. We show evidence that gene bla(VIM-4) was transmitted as a part of the class-1 integron on a ca. -90 kb conjugative plasmid. High homology of nucleotide sequence was observed between the integron found in VIM-4 producing E. cloacae and K. pneumoniae strains tested and class-1 integrons previously reporteded in Pseudomonas aeruginosa from Hungary and Poland. This finding may suggest P. aeruginosa as a potential source of acquired VIM-4 in Enterobacteriaceae.

  4. Mutations in blaKPC-3 that confer ceftazidime-avibactam resistance encode novel KPC-3 variants that function as extended-spectrum β-lactamases. (United States)

    Haidar, Ghady; Clancy, Cornelius J; Shields, Ryan K; Hao, Binghua; Cheng, Shaoji; Nguyen, M Hong


    We identified four blaKPC-3 mutations in ceftazidime-avibactam resistant clinical Klebsiella pneumoniae isolates, corresponding to D179Y, T243M, D179Y/T243M, and EL165 KPC-3 variants. Using site-directed mutagenesis and transforming vectors into Escherichia coli, we conclusively demonstrated that mutant blaKPC-3 encoded enzymes that functioned as extended-spectrum β-lactamases; mutations directly conferred higher MICs of ceftazidime-avibactam MICs, and decreased MICs of carbapenems and other β-lactams. Impact was strongest for the D179Y mutant, highlighting the importance of the KPC Ω-loop.

  5. Study on pan-resistant Klebsiella pneumoniae harboring blaKPC-2 type carbapenemase gene from a hospital outbreak in Huzhou, Zhejiang%携带blaKPC-2型碳青霉烯酶基因泛耐药肺炎克雷伯菌医院内感染暴发的病原学分析

    Institute of Scientific and Technical Information of China (English)

    黄支密; 糜家睿; 盛以泉; 邹玉秀; 储秋菊; 葛丽卫; 杨海燕


    Objective To investigate the status of genotype of the KPC(Klebsiella pneumoniae carbapenemase)-encoding genes in Pan-resistant K. Pneumoniae, isolated from the 98th Hospital of People' s Liberation Army, Huzhou district, Zhejiang province, China. Methods 19 strains of Pan-resistant K. Pneumoniae were isolated from the inpatients between November, 2008 and July,2009. Phenotypic confirmatory test for suspected carbapenemases production were carried out by Modified Hodge test. Carbapenemase gene of blaKPC was analyzed by PCR and verified by DNA sequencing. Results In 19 strains of K. Pneumoniae, the positive rates of Modified Hodge test and gene of blaKPC were both 100.0%. These genes all belonged to blaKPC-2 subtype confirmed by nucleotide sequence analysis. Among them, the blaKPC-2 gene sequence of the HZ001 strain (its original serial number was HZ9871 ) had been registered in GenBank (GenBank Accession Number: GU086225).Conclusion All of the Pan-resistant K. Pneumoniae isolated from the inpatients harbored blaKPC-2 type carbapenemases gene and causing an outbreak in a hospital. Carbapenemases that producing type KPC-2 might be the major reason which causing the resistance to Carbapenems antibiotics.%目的 了解引起医院内感染暴发临床分离的泛耐药肺炎克雷伯菌(Kpn)KPC型碳青霉烯酶基因blaKPC存在状况.方法 2008年11月至2009年7月从住院患者中分离19株泛耐药Kpn,采用改良Hodge试验检测菌株产碳青霉烯酶情况,采用PCR及序列分析的方法分析blaKPC基因.结果 19株泛耐药Kpn改良Hodge试验结果均阳性、blaKPC基因阳性率为100.0%,序列分析确认均为blaKPC-2亚型,其中HZ001号菌株(原始编号HZ9871)blaKPC-2基因序列已登录GenBank,注册号为GU086225.结论 临床分离的泛耐药Kpn均携带blaKPC-2基因,而产KPC-2型碳青霉烯酶是分离菌株对碳青霉烯类抗生素耐药的主要原因.

  6. Investigation of blaKPC and blaNDM of carbapenem-resistant Enterobacteriaceae%耐碳青霉烯类肠杆菌科细菌 KPC 与 NDM 的研究

    Institute of Scientific and Technical Information of China (English)

    陈丽; 员静; 杨洁; 热那古艾山; 季萍


    目的:检测耐碳青霉烯类肠杆菌科细菌的K PC和NDM 耐药基因,分析耐碳青霉烯类的耐药机制。方法收集2014年1月-2015年6月医院27株对碳青霉烯类抗菌药物敏感性降低的肠杆菌科细菌,筛选出耐亚胺培南或美罗培南的肠杆菌科细菌,采用改良Hodge试验初筛,聚合酶链反应(PCR)扩增检测细菌产KPC和 NDM耐药基因。结果针对碳青霉烯类抗菌药物耐药的27株菌,用改良的H o dg e试验5株阳性,有9株经PC R扩增检测细菌产KPC基因,有13株经PCR扩增检测细菌产NDM 耐药基因;基因测序比对结果为KPC‐2型碳青霉烯酶和NDM‐1型耐药基因。结论耐碳青霉烯类肠杆菌科细菌耐药机制主要携带K PC -2型碳青霉烯酶耐药基因和NDM‐1型耐药基因,临床与实验室应引起重视。%OBJECTIVE To detect blaK PC and blaNDM of carbapenem‐resistant Enterobacteriaceae ,and investi‐gate the mechanism of carbapenem‐resistance in Enterobacteriaceae .METHODS A total of 27 strains of carbapen‐em‐resistant Enterobacteriaceae from Jan .2014 to Jun .2015 were collected . Enterobacteriaceae bacteria which were resistant to imipenem or meropenem or both of them were screened .Modified Hodge test was used for early screening ,and polymerase chain reaction (PCR) amplification was used to detect drug‐resistant genes sequencing of producing KPC and NDM .RESULTS A total of 5 strains from 27 isolated strains were positive in modified Hodge test ,and there were 9 strains carrying blaK PC carbapenem‐resistant gene and 13 strains carrying blaNDM carbapenem‐resistant gene were detected by PCR .Genetic sequencing showed that KPC‐2 type carbon penicillium enzyme and NDM‐1 type resistant genes were related to drug‐resistance .CONCLUSION The mechanism of carbap‐enem‐resistance in Enterobacteriaceae is mainly due to KPC‐2 type carbon penicillium enzyme and NDM‐1 type re‐sistant genes ,which should be

  7. First characterisation of plasmid-mediated quinolone resistance-qnrS1 co-expressed bla CTX-M-15 and bla DHA-1 genes in clinical strain of Morganella morganii recovered from a Tunisian Intensive Care Unit

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    S Mahrouki


    Full Text Available Purpose: Aim of this study was to show the emergence of the qnr genes among fluoroquinolone-resistant, AMPC and ESBL (extended-spectrum-beta-lactamase co-producing Morganella morganii isolate. Materials and Methods: A multi resistant Morganella morganii SM12012 isolate was recovered from pus from a patient hospitalized in the intensive care unit at the Military hospital, Tunisia. Antibiotic susceptibility was tested with the agar disk diffusion method according to Clinical and Laboratory Standards Institute guidelines. ESBLs were detected using a standard double-disk synergy test. The characterization of beta-lactamases and associated resistance genes were performed by isoelectric focusing, polymerase chain reaction and nucleotide sequencing. Results: The antimicrobial susceptibility testing showed the high resistance to penicillins, cephalosporins (MICs: 64-512 μg/ml and fluoroquinolones (MICs: 32-512 μg/ml. But M. morganii SM12012 isolate remained susceptible to carbapenems (MICs: 4-<0.25 μg/ml. The double-disk synergy test confirmed the phenotype of extended-spectrum β-lactamases (ESBLs. Three identical β-lactamases with pI values of 6.5, 7.8 and superior to 8.6 were detected after isoelectric focusing analysis. These β-lactamases genes can be successfully transferred by the conjugative plasmid. Molecular analysis demonstrated the co-production of bla DHA-1, bla CTX-M-15 and qnrS1 genes on the same plasmid. The detection of an associated chromosomal quinolone resistance revealed the presence of a parC mutation at codon 80 (Ser80-lle80. Conclusion: This is the first report in Tunisia of nosocomial infection due to the production of CTX-M-15 and DHA-1 β-lactamases in M. morganii isolate with the association of quinolone plasmid resistance. The incidence of these strains invites continuous monitoring of such multidrug-resistant strains and the further study of their epidemiologic evolution.

  8. Emergence of blaCTX-M-15 Gene and Its Transferability in Enterobacter spp. Isolated From the Hospitals of Tehran, Iran


    Salimian Rizi; Najar Peerayeh; Bakhshi; Rahbar


    Background Enterobacter spp. is increasingly recognized as an important nosocomial pathogen and implicated in many episodes of hospital acquired infections. Objectives The current study aimed to describe distribution and transferability of blaCTX-M-15 gene, and the antibiotic susceptibility pattern in the clinical isolates of Enterobacter spp. Materials and Methods A total of 110 E...

  9. The IncP-6 Plasmid p10265-KPC from Pseudomonas aeruginosa Carries a Novel ΔISEc33-Associated blaKPC-2 Gene Cluster (United States)

    Dai, Xiaotian; Zhou, Dongsheng; Xiong, Wei; Feng, Jiao; Luo, Wenbo; Luo, Guangming; Wang, Haijing; Sun, Fengjun; Zhou, Xiangdong


    Pseudomonas aeruginosa strain 10265 was recovered from a patient with pneumonia in a Chinese public hospital, and it displays the carbapenem resistance phenotype due to the acquisition of a non-conjugative but mobilizable IncP-6-type plasmid p10265-KPC. p10265-KPC carries a Tn5563-borne defective mer locus, and a novel ΔISEc33-associated blaKPC-2 gene cluster without paired inverted repeats and paired direct repeats at both ends. Mobilization of this ΔISEc33-associated element in p10265-KPC would be attributed to homologous recombination-based insertion of a foreign structure Tn3-ISApu1-orf7-ISApu2- ISKpn27-ΔblaTEM-1-blaKPC-2-ΔISKpn6- korC-orf6-klcA-ΔrepB into a pre-existent intact ISEc33, making ISEc33 truncated at the 3′ end. The previously reported pCOL-1 represents the first sequenced KPC-producing IncP-6 plasmid, while p10265-KPC is the second one. These two plasmids carry two distinct blaKPC-2 gene clusters, which are inserted into the different sites of the IncP-6 backbone and have different evolutionary histories of assembly and mobilization. This is the first report of identification of the IncP-6-type resistance plasmid in China. PMID:27014233

  10. The IncP-6 plasmid p10265-KPC from Pseudomonas aeruginosa carries a novel ΔISEc33-associated blaKPC-2 gene cluster

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    Xiaotian eDai


    Full Text Available Pseudomonas aeruginosa strain 10265 was recovered from a patient with pneumonia in a Chinese public hospital, and it displays the carbapenem resistance phenotype due to the acquisition of a nonconjugative but mobilizable IncP-6-type plasmid p10265-KPC. p10265-KPC carries a Tn5563-borne defective mer locus and a novel ΔISEc33-associated blaKPC-2 gene cluster without paired invert repeats and direct repeats at both ends. Mobilization of this ΔISEc33-associated element in p10265-KPC would attribute to homologous recombination-based insertion of a foreign structure Tn3-ISApu1-orf7-ISApu2- ISKpn27-ΔblaTEM-1-blaKPC-2-ΔISKpn6-korC-orf6-klcA-ΔrepB into a pre-existent intact ISEc33, making ISEc33 truncated at the 3' end. The previously reported pCOL-1 represents the first sequenced KPC-producing IncP-6 plasmid, while p10265-KPC is the second one. These two plasmids carry two distinct blaKPC-2 gene clusters, which are inserted into the different sites of the IncP-6 backbone and have different evolutionary histories of assembly and mobilization. This is also the first report of identification of the IncP-6-type resistance plasmid in China.

  11. The IncP-6 Plasmid p10265-KPC from Pseudomonas aeruginosa Carries a Novel ΔISEc33-Associated bla KPC-2 Gene Cluster. (United States)

    Dai, Xiaotian; Zhou, Dongsheng; Xiong, Wei; Feng, Jiao; Luo, Wenbo; Luo, Guangming; Wang, Haijing; Sun, Fengjun; Zhou, Xiangdong


    Pseudomonas aeruginosa strain 10265 was recovered from a patient with pneumonia in a Chinese public hospital, and it displays the carbapenem resistance phenotype due to the acquisition of a non-conjugative but mobilizable IncP-6-type plasmid p10265-KPC. p10265-KPC carries a Tn5563-borne defective mer locus, and a novel ΔISEc33-associated bla KPC-2 gene cluster without paired inverted repeats and paired direct repeats at both ends. Mobilization of this ΔISEc33-associated element in p10265-KPC would be attributed to homologous recombination-based insertion of a foreign structure Tn3-ISApu1-orf7-ISApu2- ISKpn27-Δbla TEM-1 -bla KPC-2 -ΔISKpn6- korC-orf6-klcA-ΔrepB into a pre-existent intact ISEc33, making ISEc33 truncated at the 3' end. The previously reported pCOL-1 represents the first sequenced KPC-producing IncP-6 plasmid, while p10265-KPC is the second one. These two plasmids carry two distinct bla KPC-2 gene clusters, which are inserted into the different sites of the IncP-6 backbone and have different evolutionary histories of assembly and mobilization. This is the first report of identification of the IncP-6-type resistance plasmid in China.

  12. NDM-1-producing Enterobacteriaceae in a teaching hospital in Shanghai, China: IncX3-type plasmids may contribute to the dissemination of blaNDM-1

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    Hongping Qu


    Conclusion: This is the first report of NDM-1-positive Enterobacteriaceae from Shanghai, China. IncX3 plasmids, reported in various species in the United Arab Emirates and China, may contribute to the dissemination of blaNDM-1.. More attention should be devoted to monitoring the dissemination of the NDM-1 gene due to its potential horizontal transfer via mobile genetic elements.

  13. Complete Sequence of Four Multidrug-Resistant MOBQ1 Plasmids Harboring blaGES-5 Isolated from Escherichia coli and Serratia marcescens Persisting in a Hospital in Canada. (United States)

    Boyd, David; Taylor, Geoffrey; Fuller, Jeff; Bryce, Elizabeth; Embree, Joanne; Gravel, Denise; Katz, Kevin; Kibsey, Pamela; Kuhn, Magdalena; Langley, Joanne; Mataseje, Laura; Mitchell, Robyn; Roscoe, Diane; Simor, Andrew; Thomas, Eva; Turgeon, Nathalie; Mulvey, Michael


    The usefulness of carbapenems for gram-negative infections is becoming compromised by organisms harboring carbapenemases, enzymes which can hydrolyze the drug. Currently KPC (class A), NDM (class B), and OXA-48 types (class D) are the most globally widespread carbapenemases. However, among the GES-type class A extended-spectrum β-lactamases (ESBLs) there are variants that hydrolyze carbapenems, with blaGES-5 being the most common. Two Escherichia coli and two Serratia marcescens harboring blaGES-5 on plasmids were isolated by the Canadian Nosocomial Infection Surveillance Program (CNISP) from four different patients in a single hospital over a 2-year period. Complete sequencing of the blaGES-5 plasmids indicated that all four had nearly identical backbones consisting of genes for replication, partitioning, and stability, but contained variant accessory regions consisting of mobile elements and antimicrobial resistance genes. The plasmids were of a novel replicon type, but belonged to the MOBQ1 group based on relaxase sequences, and appeared to be mobilizable, but not self-transmissible. Considering the time periods of bacterial isolation, it would appear the blaGES-5 plasmid has persisted in an environmental niche for at least 2 years in the hospital. This has implications for infection control and clinical care when it is transferred to clinically relevant gram-negative organisms.

  14. A Carbapenem-Resistant Pseudomonas aeruginosa Isolate Harboring Two Copies of blaIMP-34 Encoding a Metallo-β-Lactamase.

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    Tatsuya Tada

    Full Text Available A carbapenem-resistant strain of Pseudomonas aeruginosa, NCGM1984, was isolated in 2012 from a hospitalized patient in Japan. Immunochromatographic assay showed that the isolate was positive for IMP-type metallo-β-lactamase. Complete genome sequencing revealed that NCGM1984 harbored two copies of blaIMP-34, located at different sites on the chromosome. Each blaIMP-34 was present in the same structures of the class 1 integrons, tnpA(ISPa7-intI1-qacG-blaIMP-34-aac(6'-Ib-qacEdelta1-sul1-orf5-tniBdelta-tniA. The isolate belonged to multilocus sequence typing ST235, one of the international high-risk clones. IMP-34, with an amino acid substitution (Glu126Gly compared with IMP-1, hydrolyzed all β-lactamases tested except aztreonam, and its catalytic activities were similar to IMP-1. This is the first report of a clinical isolate of an IMP-34-producing P. aeruginosa harboring two copies of blaIMP-34 on its chromosome.

  15. The IncI1 plasmid carrying the bla CTX-M-1 gene persists in in vitro culture of a Escherichia coli strain from broilers

    NARCIS (Netherlands)

    Fischer, E.A.J.; Dierikx, C.M.; Essen-Zandbergen, van A.; Roermund, van H.J.W.; Mevius, D.J.; Stegeman, A.; Klinkenberg, D.


    Commensal bacteria are a reservoir for antimicrobial-resistance genes. In the Netherlands, bacteria producing Extended Spectrum Beta-Lactamases (ESBL) are found on chicken-meat and in the gut of broilers at a high prevalence and the predominant ESBL-gene is the blaCTX-M-1 located on IncI1 plasmids.

  16. [Clonal relationship and detection of blaKPC gene in strains of Klebsiella pneumoniae resistant to carbapenems, at a hospital in Venezuela]. (United States)

    Martínez, Dianny; Araque, Yasmina; Roduifo, Hectorina; Caña, Luisa; García, José; Gonzáiez, Diorelis; Rodríguez, Lucy; De Donato, Marcos


    In order to study the clonal relationship and blaKPC gene detection in clinical isolates of Klebsiella pneumoniae resistant to carbapenems, we analyzed 22 clinical isolates of K. pneumoniae with resistance to imipenem and/ or meropenem, isolated in the laboratory of bacteriology at the University Hospital "Antonio Patricio de Alcalá" (HUAPA) from the Cumana city, Sucre state, Venezuela, for a period of five consecutive years. Susceptibility to different antimicrobials was determined, and the presence of carbapenemases was detected by modified Hodge method, phenyl boronic acid synergy and combination discs. blaKPC gene detection was conducted by polymerase chain reaction and the clonal relationship was determined by pulsed field electrophoresis. High rates of antimicrobial resistance were found, five strains were negative, at least one phenotypic method, and all carried the blaKPC gene. Clonal spread was observed only in the intensive care unit (ICU), while in other services, polyclonality was found. We concluded that blaKPC gene is present in K. pneumoniae strains resistant to carbapenems isolated in the HUAPA and clonal spread it was only in the ICU.

  17. Complete nucleotide sequence of pGA45, a 140,698-bp incFIIY plasmid encoding blaIMI-3-mediated carbapenem resistance, from river sediment

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    Bingjun eDang


    Full Text Available Plasmid pGA45 was isolated from the sediment of Haihe River using E. coli CV601 (gfp-tagged as recipients and indigenous bacteria from sediment as donors. This plasmid confers reduced susceptibility to imipenem which belongs to carbapenem group. Plasmid pGA45 was fully sequenced on an Illumina HiSeq 2000 sequencing system. The complete sequence of plasmid pGA45 was 140,698 bp in length with an average G+C content of 52.03%. Sequence analysis shows that pGA45 belongs to incFIIY group and harbors a backbone region shares high homology and gene synteny to several other incF plasmids including pNDM1_EC14653, pYDC644, pNDM-Ec1GN574, pRJF866, pKOX_NDM1 and pP10164-NDM. In addition to the backbone region, plasmid pGA45 harbors two notable features including one blaIMI-3-containing region and one type VI secretion system region. The blaIMI-3-containing region is responsible for bacteria carbapenem resistance and the type VI secretion system region is probably involved in bacteria virulence, respectively. Plasmid pGA45 represents the first complete nucleotide sequence of the blaIMI-harboring plasmid from environment sample and the sequencing of this plasmid provided insight into the architecture used for the dissemination of blaIMI carbapenemase genes.

  18. Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase

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    Adriano Martison Ferreira

    Full Text Available Abstract Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28 mm (penicillin resistant and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29 mm, 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%, followed by MIC determination (85.5%, but the specificity of the former was low (40.0%. The nitrocefin test was the least sensitive (28.9%. However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%. The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

  19. Correlation of phenotypic tests with the presence of the blaZ gene for detection of beta-lactamase. (United States)

    Ferreira, Adriano Martison; Martins, Katheryne Benini; Silva, Vanessa Rocha da; Mondelli, Alessandro Lia; Cunha, Maria de Lourdes Ribeiro de Souza da

    Staphylococcus aureus and Staphylococcus saprophyticus are the most common and most important staphylococcal species associated with urinary tract infections. The objective of the present study was to compare and to evaluate the accuracy of four phenotypic methods for the detection of beta-lactamase production in Staphylococcus spp. Seventy-three strains produced a halo with a diameter ≤28mm (penicillin resistant) and all of them were positive for the blaZ gene. Among the 28 susceptible strain (halo ≥29mm), 23 carried the blaZ gene and five did not. The zone edge test was the most sensitive (90.3%), followed by MIC determination (85.5%), but the specificity of the former was low (40.0%). The nitrocefin test was the least sensitive (28.9%). However, the nitrocefin test together with the disk diffusion method showed the highest specificity (100%). The present results demonstrated that the zone edge test was the most sensitive phenotypic test for detection of beta-lactamase, although it is still not an ideal test to detect this type of resistance since its specificity was low. However, the inhibition halo diameter of the penicillin disk can be used together with the zone edge test since the same disk is employed in the two tests. Combined analysis of the two tests shows a sensitivity of 90.3% and specificity of 100%, proving better sensitivity, especially for S. saprophyticus. This is a low-cost test of easy application and interpretation that can be used in small and medium-sized laboratories where susceptibility testing is usually performed by the disk diffusion method.

  20. Impact of three ampicillin dosage regimens on selection of ampicillin resistance in Enterobacteriaceae and excretion of blaTEM genes in swine feces. (United States)

    Bibbal, D; Dupouy, V; Ferré, J P; Toutain, P L; Fayet, O; Prère, M F; Bousquet-Mélou, A


    The aim of this study was to assess the impact of three ampicillin dosage regimens on ampicillin resistance among Enterobacteriaceae recovered from swine feces by use of phenotypic and genotypic approaches. Phenotypically, ampicillin resistance was determined from the percentage of resistant Enterobacteriaceae and MICs of Escherichia coli isolates. The pool of ampicillin resistance genes was also monitored by quantification of bla(TEM) genes, which code for the most frequently produced beta-lactamases in gram-negative bacteria, using a newly developed real-time PCR assay. Ampicillin was administered intramuscularly and orally to fed or fasted pigs for 7 days at 20 mg/kg of body weight. The average percentage of resistant Enterobacteriaceae before treatment was between 2.5% and 12%, and bla(TEM) gene quantities were below 10(7) copies/g of feces. By days 4 and 7, the percentage of resistant Enterobacteriaceae exceeded 50% in all treated groups, with some highly resistant strains (MIC of >256 microg/ml). In the control group, bla(TEM) gene quantities fluctuated between 10(4) and 10(6) copies/g of feces, whereas they fluctuated between 10(6) to 10(8) and 10(7) to 10(9) copies/g of feces for the intramuscular and oral routes, respectively. Whereas phenotypic evaluations did not discriminate among the three ampicillin dosage regimens, bla(TEM) gene quantification was able to differentiate between the effects of two routes of ampicillin administration. Our results suggest that fecal bla(TEM) gene quantification provides a sensitive tool to evaluate the impact of ampicillin administration on the selection of ampicillin resistance in the digestive microflora and its dissemination in the environment.

  1. Spread of the blaOXA–23-Containing Tn2008 in Carbapenem-Resistant Acinetobacter baumannii Isolates Grouped in CC92 from China (United States)

    Chen, Yisheng; Gao, Jing; Zhang, Haomin; Ying, Chunmei


    The rapid expansion of carbapenem-resistant Acinetobacter baumannii (CRAB) clinical isolates is a big issue. We investigated the antibiotic susceptibility, molecular epidemiology and resistance gene of A. baumannii collected at two hospitals in Shanghai, China. Besides, the A. baumannii PCR-based replicon typing method (AB-PBRT) was conducted to categorize the plasmids into homogeneous groups on the basis of replicase genes. Most CRAB isolates showed high-level resistance to almost all antibiotics but retain susceptibility to colistin and tigecycline. A total of 101 isolates carried blaOXA-51-like gene. Sequencing identified the presence of blaOXA-66 for CRAB isolates. blaOXA–23 gene were discovered in all CRAB isolates. Each CRAB isolate contained 1–3 of 19 different plasmid replicase (rep) gene homology groups (GRs) and the GR6 (repAci6) was ubiquitous. Genotyping by Multilocus Sequence Typing (MLST) showed seven defined MLST patterns and three novel STs were found. eBURST analysis indicated they were all grouped in CC92 (GCII) with the most frequent ST208 (50%). Two blaOXA–23-bearing transposons were found: Tn2006 and Tn2008. Tn2008 were detected in 54 (96.4%) isolates and Tn2006 in two remaining isolates. The blaOXA–23 carbapenem gene was vitally associated with repAci6 plasmid belong to CC92 clonal group. Our survey revealed severe drug resistance in A. baumannii isolates. Tn2008-containing CC92 A. baumannii were endemic, which may facilitate the blaoxa23 dissemination. PMID:28220115

  2. The influence of stress on fear memory processes

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    I.D. Martijena


    Full Text Available It is well recognized that stressful experiences promote robust emotional memories, which are well remembered. The amygdaloid complex, principally the basolateral complex (BLA, plays a pivotal role in fear memory and in the modulation of stress-induced emotional responses. A large number of reports have revealed that GABAergic interneurons provide a powerful inhibitory control of the activity of projecting glutamatergic neurons in the BLA. Indeed, a reduced GABAergic control in the BLA is essential for the stress-induced influence on the emergence of associative fear memory and on the generation of long-term potentiation (LTP in BLA neurons. The extracellular signal-regulated kinase (ERK subfamily of the mitogen-activated protein kinase (MAPK signaling pathway in the BLA plays a central role in the consolidation process and synaptic plasticity. In support of the view that stress facilitates long-term fear memory, stressed animals exhibited a phospho-ERK2 (pERK2 increase in the BLA, suggesting the involvement of this mechanism in the promoting influence of threatening stimuli on the consolidation fear memory. Moreover, the occurrence of reactivation-induced lability is prevented when fear memory is encoded under intense stressful conditions since the memory trace remains immune to disruption after recall in previously stressed animals. Thus, the underlying mechanism in retrieval-induced instability seems not to be functional in memories formed under stress. All these findings are indicative that stress influences both the consolidation and reconsolidation fear memory processes. Thus, it seems reasonable to propose that the emotional state generated by an environmental challenge critically modulates the formation and maintenance of long-term fear memory.

  3. Spread of blaCTX-M-14 Is Driven Mainly by IncK Plasmids Disseminated among Escherichia coli Phylogroups A, B1, and D in Spain▿ (United States)

    Valverde, Aránzazu; Cantón, Rafael; Garcillán-Barcia, M. Pilar; Novais, Ângela; Galán, Juan Carlos; Alvarado, Andrés; de la Cruz, Fernando; Baquero, Fernando; Coque, Teresa M.


    Since its first description in 2000, CTX-M-14 has become one of the most widespread extended-spectrum β-lactamases in Spain. In the present Escherichia coli multilevel population genetic study involving the characterization of phylogroups, clones, plasmids, and genetic platforms, 61 isolates from 16 hospitalized patients and 40 outpatients and healthy volunteers recovered from 2000 to 2005 were analyzed. Clonal relatedness (XbaI pulsed-field gel electrophoresis [PFGE] type, phylogenetic group, multilocus sequence type [MLST]) was established by standard methods. Analysis of transferred plasmids (I-CeuI; S1 nuclease; restriction fragment length polymorphism analysis; and analysis of RNA interference, replicase, and relaxase) was performed by PCR, sequencing, and hybridization. The genetic environment of blaCTX-M-14 was characterized by PCR on the basis of known associated structures (ISEcp1, IS903, ISCR1). The isolates were mainly recovered from patients in the community (73.8%; 45/61) with urinary tract infections (62.2%; 28/45). They were clonally unrelated by PFGE and corresponded to phylogenetic groups A (36.1%), D (34.4%), and B1 (29.5%). MLST revealed a high degree of sequence type (ST) diversity among phylogroup D isolates and the overrepresentation of the ST10 complex among phylogroup A isolates and ST359/ST155 among phylogroup B1 isolates. Two variants of blaCTX-M-14 previously designated blaCTX-M-14a (n = 59/61) and blaCTX-M-14b (n = 2/61) were detected. blaCTX-M-14a was associated with either ISEcp1 within IncK plasmids (n = 27), ISCR1 linked to an IncHI2 plasmid (n = 1), or ISCR1 linked to IncI-like plasmids (n = 3). The blaCTX-M-14b identified was associated with an ISCR1 element located in an IncHI2 plasmid (n = 1) or with ISEcp1 located in IncK (n = 1). The CTX-M-14-producing E. coli isolates in our geographic area are frequent causes of community-acquired urinary tract infections. The increase in the incidence of such isolates is mostly due to the

  4. Coexistence of blaOXA-23 with armA in quinolone-resistant Acinetobacter baumannii from a Chinese university hospital. (United States)

    Shen, Min; Luan, Guangxin; Wang, Yanhong; Chang, Yaowen; Zhang, Chi; Yang, Jingni; Deng, Shanshan; Ling, Baodong; Jia, Xu


    A total of 101 Acinetobacter baumannii isolates were collected to determine the mechanisms of quinolone resistance and investigate the occurrence of carbapenem and high-level aminoglycoside resistance genes among quinolone-resistant strains. Among 77 quinolone-resistant A. baumannii harbored mutations of gyrA and parC, 41 isolates, which belonged to European clone II, had resistance to aminoglycosides and carbapenems due to the expression of armA and acquisition of blaOXA-23. Most of sequence type belonged to clonal complex 92. These results suggested hospital dissemination of multidrug-resistant A. baumannii carrying blaOXA-23, armA, and mutations of quinolone resistance-determining regions in western China.

  5. pIMP-PH114 carrying bla IMP-4 in a Klebsiella pneumoniae strain is closely related to other multidrug-resistant IncA/C2 plasmids. (United States)

    Ho, Pak-Leung; Lo, Wai-U; Chan, Jane; Cheung, Yuk-Yam; Chow, Kin-Hung; Yam, Wing-Cheong; Lin, Chi-Ho; Que, Tak-Lun


    The IncA/C plasmids are broad host-range vehicles which have been associated with wide dissemination of CMY-2 among Enterobacteriaceae of human and animal origins. Acquired metallo-β-lactamases (MBLs) such as the IMP-type enzymes are increasingly reported in multidrug-resistant Gram-negative bacteria worldwide, particularly in Enterobacteriaceae. We described the complete sequence of the first IMP-4-encoding IncA/C2 plasmid, pIMP-PH114 (151,885 bp), from a sequence type 1 Klebsiella pneumoniae strain that was recovered from a patient who was hospitalized in the Philippines. pIMP-PH114 consists of a backbone from the IncA/C2 plasmids, with the insertion of a novel Tn21-like class 1 integron composite structure (containing the cassette array bla IMP-4-qacG-aacA4-catB3, followed by a class C β-lactamase bla DHA-1 and the mercury resistance operon, merRTPCADE) and a sul2-floR encoding region. Phylogenetic analysis of the IncA/C repA sequences showed that pIMP-PH114 formed a subgroup with other IncA/C plasmids involved in the international spread of CMY-2, TEM-24 and NDM-1. Identical bla IMP-4 arrays have been described among different Enterobacteriaceae and Acinetobacter spp. in China, Singapore and Australia but the genetic context is different. The broad host range of IncA/C plasmids may have facilitated dissemination of the bla IMP-4 arrays among different diverse groups of bacteria.

  6. Diversity of the Genetic Environment of the blaKPC-2 Gene Among Klebsiella pneumoniae Clinical Isolates in a Chinese Hospital. (United States)

    Wang, Lian-Hui; Wei, Dan-Dan; Wan, La-Gen; Yu, Yang; Deng, Qiong; Liu, Yang


    KPC-producing Klebsiella pneumoniae (KPC-Kp) has been frequently reported worldwide and constitutes a major healthcare threat, given their extensively drug-resistant phenotypes. In this study, we report the characterization of the genetic environment of blaKPC-2 gene in KPC-Kp clinical strains from China belonging to diverse genotypes. Thirty-five nonduplicated KPC-Kp isolates collected in a Chinese hospital during 2012 were analyzed. All were multidrug resistant due to the presence of other resistance determinants, including metallo-β-lactamases (IMP-4, NDM-1), extended-spectrum β-lactamases (CTX-M-14, -15, -3, -10, and SHV-12), 16S rRNA methylases (armA and rmtB), and plasmid-mediated quinolone resistance determinants [qnrA, B, S, aac(6')-Ib-cr]. Using pulsed-field gel electrophoresis (PFGE), the 35 isolates were grouped into 12 clusters that were further identified as 15 sequence types (STs) by multilocus sequence typing. ST11 K. pneumoniae was the predominant clone attributed to the outbreak. blaKPC-2 was carried in plasmids of various sizes and incompatibility types. The genetic environment analysis, based on genetic structure in the plasmid pKP048, revealed five distinct platforms: the most prevalent structure was the continual occurrence in diverse STs (ST11, ST258, ST340, ST395, ST437, and ST494), harboring plasmid of blaKPC-2 in a genetic environment flanked by ISKpn8 and ISKpn6 like. This study highlights the continued evolution of the genetic environment of the blaKPC-2 gene in our hospital and movement to multiple plasmid backbones that results in acquisition by multiple clones of K. pneumoniae.

  7. Sequential isolation in a patient of Raoultella planticola and Escherichia coli bearing a novel ISCR1 element carrying blaNDM-1.

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    Juan Li

    Full Text Available BACKGROUND: The gene for New Delhi metallo-β-lactamase 1 (NDM-1 has been reported to be transmitted via plasmids which are easily transferable and capable of wide distribution. We report the isolation of two NDM-1 producing strains and possible in vivo transfer of blaNDM-1 in a patient. METHODS: Clinical samples were collected for bacterial culture and antibiotic susceptibility testing from a patient during a 34-day hospitalization. The presence of blaNDM-1 was detected by PCR and sequencing. Plasmids of interest were sequenced. Medical records were reviewed for evidence of association between the administration of antibiotics and the acquisition of the NDM-1 resistance. RESULTS: A NDM-1 positive Raoultella planticola was isolated from blood on the ninth day of hospitalization without administration of any carbapenem antibiotics and a NDM-1 positive Escherichia coli was isolated from feces on the 29th day of hospitalization and eight days after imipenem administration. The blaNDM-1 was carried by a 280 kb plasmid pRpNDM1-1 in R. planticola and a 58 kb plasmid pEcNDM1-4 in E. coli. The two plasmids shared a 4812 bp NDM-1-ISCR1 element which was found to be excisable from the plasmid as a free form and transferrable in vitro to a NDM-1 negative plasmid from E. coli. CONCLUSION: blaNDM-1 was embedded in an ISCR1 complex class 1 integron as a novel 4812 bp NDM-1-ISCR1 element. The element was found to be able to self excise to become a free form, which may provide a new vehicle for NDM-1 dissemination. This mechanism could greatly accelerate the spread of NDM-1 mediated broad spectrum β-lactam resistance.

  8. Molecular detection of metallo-β-lactamase gene blaVIM-1 in imipenem-resistant Pseudomonas aeruginosa strains isolated from hospitalized patients in the hospitals of Isfahan

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    Mansour Sedighi


    Conclusion: The results demonstrated the serious therapeutic threat of the MBL-producing P. aeruginosa populations. The rate of imipenem resistance due to MBL was increased dramatically. Early detection and infection-control practices are the best antimicrobial strategies for this organism. None of MBL-producing isolates in this study carry the blaVIM-1 gene; therefore, another gene in the MBL family should be investigated.

  9. Vibrio cholerae InV117, a Class 1 Integron Harboring aac(6′)-Ib and blaCTX-M-2, Is Linked to Transposition Genes


    Alfonso J C Soler Bistué; Martín, Fernando A.; Petroni, Alejandro; Faccone, Diego; Galas, Marcelo; Tolmasky, Marcelo E.; Zorreguieta, Angeles


    A ca. 150-kbp Vibrio cholerae O1 biotype El Tor plasmid includes blaCTX-M-2 and a variant of aac(6′)-Ib within InV117, an orf513-bearing class 1 integron. InV117 is linked to a tnp1696 module in which IRl carries an insertion of IS4321R. The complete structure could be a potential mobile element.

  10. Detection of Ampicillin Resistance Genes (bla in Clinical Isolates of Escherichia coli with Polymerase Chain Reaction Method

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    Tiana Milanda


    Full Text Available Escherichia coli is a rod negative Gram which could be pathogenic, if its value increases or located in outer gastrointestinal tract. Pathogenic E. coli will produce enterotoxin which will cause diarrhoea or infection in urine tract. Ampicilin was one of particular antibiotics to overcome infection. Ampicilin nowadays is no longer used as primary medicine, because of its resistance case. The aim of this research is to detect the presence of gene which is responsible to ampicilin resistant E. coli. We used isolated midstream urine from cystitis object in Hasan Sadikin Hospital (RSHS as samples. Polymerase Chain Reaction (PCR method (colony-PCR and DNA-PCR were done to invenstigate the antibiotic resistency. Based on the result of antibiotic susceptibility testing to ampicillin, E. coli samples were resistant to ampicilin. Elektroforegram products of colony-PCR and DNA-PCR showed that the resistance case of ampicilin caused by bla gene (199 bp. Selective and rational antibiotic treatment is required to prevent ampicillin resistance in patients with symptoms

  11. Evaluation of modified hodge test as an indicator of klebsiella pneumoniae carbapenemase (KPC production by using bla kpc gene PCR

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    Priyadarshini Shanmugam, Nirupa Soundararajan, Jeya Meenakshisundaram


    Full Text Available Introduction: Carbapenems belong to the Beta Lactam group of antimicrobial agents. They are often used as “last-line agents” or “antibiotics of last resort” in critically ill patients. Carbapenem resistance in Enterobacteriaceae may be due to various reasons but Klebsiella pneumoniae Carbapenemase (KPC enzyme production is the commonest. Phenotypic as well as genotypic methods can be used to detect Carbapenemases. Among the phenotypic tests, Modified Hodge Test (MHT is relatively easy to perform. Aims and Objectives: This study aimed to determine the prevalence of carbapenem resistance among Enterobacteriaceae isolates and calculate the sensitivity of MHT as an indicator of KPC production. Materials and Methods: All Enterobacteriaceae isolates from clinical samples were included in this study and were screened for Carbapenem resistance. 45 randomly chosen Carbapenem Resistant Enterobacteriaceae isolates were subjected to MHT and blaKPC gene detection by PCR. Results: 2035 Enterobacteriaceae isolates were tested and 5.2% were found to be resistant to Imipenem, 22.9 % were resistant to Meropenem and 4.42 % were resistant to both Imipenem and Meropenem. The sensitivity of MHT was calculated to be 90% and specificity was calculated to be 60%

  12. Rapid emergence of high-level tigecycline resistance in Escherichia coli strains harbouring blaNDM-5 in vivo. (United States)

    Li, Xi; Mu, Xinli; Yang, Yunxing; Hua, Xiaoting; Yang, Qing; Wang, Nanfei; Du, Xiaoxing; Ruan, Zhi; Shen, Xiaoqiang; Yu, Yunsong


    Tigecycline (TIG) resistance is a growing concern because this antibiotic is regarded as one of the last resorts to treat infections caused by multidrug-resistant and extensively drug-resistant (XDR) bacteria. Information regarding TIG-resistant Escherichia coli isolates is scarce. In this study, we report the emergence of high-level TIG resistance in a longitudinal series of XDR E. coli isolates collected during TIG treatment. Whole-genome sequencing was performed for six E. coli strains harbouring bla(NDM-5) and genomic comparison revealed two amino acid substitutions. Mutation in rpsJ could be a significant factor conferring TIG resistance in these isolates. The fitness cost of TIG resistance in resistant strains was evaluated by determining the relative growth rate, indicating that TIG resistance reduced fitness by ca. 7%. This study is the first report to demonstrate high-level TIG resistance in E. coli in vivo. In addition, we report the first treatment-emergent minimum inhibitory concentration (MIC) development of TIG from 1mg/L to 64 mg/L in E. coli. Clinicians should be aware of the risk of an increase in the MIC of TIG under therapy.

  13. Complex integrons containing qnrB4-ampC (bla(DHA-1)) in plasmids of multidrug-resistant Citrobacter freundii from wastewater. (United States)

    Yim, Grace; Kwong, Waldan; Davies, Julian; Miao, Vivian


    Microbial populations in wastewater treatment plants (WWTPs) are increasingly being recognized as environmental reservoirs of antibiotic resistance genes. PCR amplicons for plasmid-mediated quinolone resistance determinants qnrA, qnrB, and qnrS were recorded in samples from a WWTP in Vancouver, British Columbia. Six strains of ciprofloxacin-resistant Citrobacter freundii were isolated and found to carry mutations in gyrA and parC, as well as multiple plasmid-borne resistance genes, collectively including qnrB; aac(6')-Ib-cr; β-lactamase-encoding genes from molecular classes A (blaTEM-1), C (ampC), D (blaOXA-1, blaOXA-10); and genes for resistance to 5 other types of antibiotics. In 3 strains, large (>60 kb) plasmids carried qnrB4 and ampC as part of a complex integron in a 14 kb arrangement that has been reported worldwide but, until recently, only among pathogenic strains of Klebsiella. Analysis of single-nucleotide polymorphisms in the qnrB4-ampC regions infers 2 introductions into the WWTP environment. These results suggest recent passage of plasmid-borne fluoroquinolone and β-lactam resistance genes from pathogens to bacteria that may be indigenous inhabitants of WWTPs, thus contributing to an environmental pool of antibiotic resistance.

  14. High-level fluoroquinolone resistant Salmonella enterica serovar Kentucky ST198 epidemic clone with IncA/C conjugative plasmid carrying bla(CTX-M-25) gene. (United States)

    Wasyl, Dariusz; Kern-Zdanowicz, Izabela; Domańska-Blicharz, Katarzyna; Zając, Magdalena; Hoszowski, Andrzej


    Multidrug resistant Salmonella Kentucky strains have been isolated from turkeys in Poland since 2009. Multiple mutations within chromosomal genes gyrA and parC were responsible for high-level ciprofloxacin resistance. One of the isolates was extended spectrum β-lactamase- (ESBL) positive: the strain 1643/2010 carried a conjugative 167,779 bps plasmid of IncA/C family. The sequence analysis revealed that it carried a blaCTX-M-25 gene and an integron with another β-lactamase encoding gene-blaOXA-21. This is the first known report of a CTX-M-25 encoding gene both in Poland and in Salmonella Kentucky world-wide, as well as in the IncA/C plasmid. Analysis of the integron showed a novel arrangement of gene cassettes-aacA4, aacC-A1 and blaOXA-21 where the latter might result from an intergeneric gene transfer. The study confirmed Salmonella Kentucky population isolated in Poland belongs to global epidemics of high level fluoroquinolone resistant clone ST198 that can carry rare β-lactamase genes.

  15. blaCMY-2-positive IncA/C plasmids from Escherichia coli and Salmonella enterica are a distinct component of a larger lineage of plasmids. (United States)

    Call, Douglas R; Singer, Randall S; Meng, Da; Broschat, Shira L; Orfe, Lisa H; Anderson, Janet M; Herndon, David R; Kappmeyer, Lowell S; Daniels, Joshua B; Besser, Thomas E


    Large multidrug resistance plasmids of the A/C incompatibility complex (IncA/C) have been found in a diverse group of Gram-negative commensal and pathogenic bacteria. We present three completed sequences from IncA/C plasmids that originated from Escherichia coli (cattle) and Salmonella enterica serovar Newport (human) and that carry the cephamycinase gene blaCMY-2. These large plasmids (148 to 166 kbp) share extensive sequence identity and synteny. The most divergent plasmid, peH4H, has lost several conjugation-related genes and has gained a kanamycin resistance region. Two of the plasmids (pAM04528 and peH4H) harbor two copies of blaCMY-2, while the third plasmid (pAR060302) harbors a single copy of the gene. The majority of single-nucleotide polymorphisms comprise nonsynonymous mutations in floR. A comparative analysis of these plasmids with five other published IncA/C plasmids showed that the blaCMY-2 plasmids from E. coli and S. enterica are genetically distinct from those originating from Yersinia pestis and Photobacterium damselae and distal to one originating from Yersinia ruckeri. While the overall similarity of these plasmids supports the likelihood of recent movements among E. coli and S. enterica hosts, their greater divergence from Y. pestis or Y. ruckeri suggests less recent plasmid transfer among these pathogen groups.

  16. Characterization of IncN plasmids carrying blaCTX-M-1 and qnr genes in Escherichia coli and Salmonella from animals, the environment and humans

    DEFF Research Database (Denmark)

    Dolejska, Monika; Villa, Laura; Hasman, Henrik;


    and ST8, respectively. Related plasmids circulating in human and animal isolates were identified. Complete nucleotide sequences of the ST1 pHHA45 plasmid carrying blaCTX-M-1, isolated from E. coli from pigs in Denmark, and the ST3 pKT58A plasmid harbouring qnrS1, identified in E. coli from a water bird......Objectives The aim of the study was to characterize a collection of Escherichia coli and Salmonella harbouring qnr and blaCTX-M-1 genes on IncN plasmids isolated from humans, food-producing, companion and wild animals, and the environment from six European countries.Methods Nineteen IncN plasmids...... DNA purified from the respective E. coli transformants.Results Three types of IncN plasmids carrying blaCTX-M-1, qnrS1 and qnrB19 genes were identified in strains isolated from the Czech Republic, Poland, Slovakia, Denmark, Italy and the Netherlands, corresponding to pMLST sequence type (ST) 1, ST3...

  17. Crystal Structure of Cockroach Allergen Bla g 2, an Unusual Zinc Binding Aspartic Protease with a Novel Mode of Self-inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Gustchina, Alla; Li, Mi; Wunschmann, Sabina; Chapman, Martin D.; Pomes, Anna; Wlodawer, Alexander (INDOOR Bio.); (NIH)


    The crystal structure of Bla g 2 was solved in order to investigate the structural basis for the allergenic properties of this unusual protein. This is the first structure of an aspartic protease in which conserved glycine residues, in two canonical DTG triads, are substituted by different amino acid residues. Another unprecedented feature revealed by the structure is the single phenylalanine residue insertion on the tip of the flap, with the side-chain occupying the S1 binding pocket. This and other important amino acid substitutions in the active site region of Bla g 2 modify the interactions in the vicinity of the catalytic aspartate residues, increasing the distance between them to {approx}4 {angstrom} and establishing unique direct contacts between the flap and the catalytic residues. We attribute the absence of substantial catalytic activity in Bla g 2 to these unusual features of the active site. Five disulfide bridges and a Zn-binding site confer stability to the protein, which may contribute to sensitization at lower levels of exposure than other allergens.

  18. Characterisation of IncA/C2 plasmids carrying an In416-like integron with the blaVIM-19 gene from Klebsiella pneumoniae ST383 of Greek origin

    NARCIS (Netherlands)

    Papagiannitsis, Costas C; Dolejska, Monika; Izdebski, Radosław; Giakkoupi, Panagiota; Skálová, Anna; Chudějová, Kateřina; Dobiasova, Hana; Vatopoulos, Alkiviadis C; Derde, Lennie P G; Bonten, Marc J M; Gniadkowski, Marek; Hrabák, Jaroslav


    The complete nucleotide sequences of three multidrug resistance (MDR) IncA/C-like plasmids from Enterobacteriaceae isolates carrying the VIM-type carbapenemase-encoding integrons In4863 (blaVIM-19-aacA7-dfrA1-ΔaadA1-smr2) or In4873 (blaVIM-1-aacA7-dfrA1-ΔaadA1-smr2) were determined, which are the fi

  19. Optogenetic Stimulation of Lateral Amygdala Input to Posterior Piriform Cortex Modulates Single-Unit and Ensemble Odor Processing. (United States)

    Sadrian, Benjamin; Wilson, Donald A


    Olfactory information is synthesized within the olfactory cortex to provide not only an odor percept, but also a contextual significance that supports appropriate behavioral response to specific odor cues. The piriform cortex serves as a communication hub within this circuit by sharing reciprocal connectivity with higher processing regions, such as the lateral entorhinal cortex and amygdala. The functional significance of these descending inputs on piriform cortical processing of odorants is currently not well understood. We have employed optogenetic methods to selectively stimulate lateral and basolateral amygdala (BLA) afferent fibers innervating the posterior piriform cortex (pPCX) to quantify BLA modulation of pPCX odor-evoked activity. Single unit odor-evoked activity of anesthetized BLA-infected animals was significantly modulated compared with control animal recordings, with individual cells displaying either enhancement or suppression of odor-driven spiking. In addition, BLA activation induced a decorrelation of odor-evoked pPCX ensemble activity relative to odor alone. Together these results indicate a modulatory role in pPCX odor processing for the BLA complex. This interaction could contribute to learned changes in PCX activity following associative conditioning, as well as support alternate patterns of odor processing that are state-dependent.

  20. Common findings of bla CTX-M-55-encoding 104-139 kbp plasmids harbored by extended-spectrum β-lactamase-producing Escherichia coli in pork meat, wholesale market workers, and patients with urinary tract infection in Vietnam. (United States)

    Hoang, T A V; Nguyen, T N H; Ueda, S; Le, Q P; Tran, T T N; Nguyen, T N D; Dao, T V K; Tran, M T; Le, T T T; Le, T L; Nakayama, T; Hirai, I; Do, T H; Vien, Q M; Yamamoto, Y


    Extended-spectrum, β-lactamase-producing Escherichia coli (ESBL-E) harboring the bla CTX-M-55-encoding plasmid (ESBL-E55) has been reported to be associated with urinary tract infection (UTI). The aims of this study were to clarify the prevalence of ESBL-E55 in pork meats and workers from the same wholesale market, as well as patients with UTI from a nearby hospital in Vietnam; we also investigated the plasmids encoding bla CTX-M-55. Sequencing analysis showed that 66.6% of the ESBL-E isolated from pork meats contained bla CTX-M-55, whereas the gene was present in 25.0% of workers and 12.5% of patients with UTI. Plasmid analysis showed that several sizes of plasmid encoded bla CTX-M-55 in ESBL-E55 isolated from pork meats, whereas ESBL-E55 isolated from workers and patients with UTI contained only 104-139 kbp of bla CTX-M-55-encoding plasmids. This indicates that the 104-139 kbp sizes of bla CTX-M-55-encoding plasmids were commonly disseminated in pork meats, wholesale market workers, and patients with UTI.

  1. Loop-mediated isothermal amplification assay targeting the blaCTX-M9 gene for detection of extended spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae. (United States)

    Thirapanmethee, Krit; Pothisamutyothin, Kanokporn; Nathisuwan, Surakit; Chomnawang, Mullika T; Wiwat, Chanpen


    Extended-spectrum β-lactamases (ESBLs) produced by Enterobacteriaceae are one of the resistance mechanisms to most β-lactam antibiotics. ESBLs are currently a major problem in both hospitals and community settings worldwide. Rapid and reliable means of detecting ESBL-producing bacteria is necessary for identification, prevention and treatment. Loop-mediated isothermal amplification (LAMP) is a technique that rapidly amplifies DNA with high specificity and sensitivity under isothermal conditions. This study was aimed to develop a convenient, accurate and inexpensive method for detecting ESBL-producing bacteria by a LAMP technique. ESBLs-producing Escherichia coli and Klebsiella pneumoniae were isolated from a tertiary hospital in Bangkok, Thailand and reconfirmed by double-disk synergy test. A set of four specific oligonucleotide primers of LAMP for detection of bla(CTX-M9) gene was designed based on bla(CTX-M9) from E. coli (GenBank Accession No. AJ416345). The LAMP reaction was amplified under isothermal temperature at 63°C for 60 min. Ladder-like patterns of band sizes from 226 bp of the bla(CTX-M9) DNA target was observed. The LAMP product was further analyzed by restriction digestion with MboI and TaqI endonucleases. The fragments generated were approximately 168, 177 and 250 bp in size for MboI digestion and 165, 193, 229, 281 and 314 bp for TaqI digestion, which is in agreement with the predicted sizes. The sensitivity of the LAMP technique to bla(CTX-M9) was greater than that of the PCR method by at least 10,000-fold. These results showed that the LAMP primers specifically amplified only the bla(CTX-M9) gene. Moreover, the presence of LAMP amplicon was simply determined by adding SYBR Green I in the reaction. In conclusion, this technique for detection of ESBLs is convenient, reliable and easy to perform routinely in hospitals or laboratory units in developing countries.

  2. Optogenetic stimulation of lateral amygdala input to posterior piriform cortex modulates single-unit and ensemble odor processing

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    Benjamin eSadrian


    Full Text Available Olfactory information is synthesized within the olfactory cortex to provide not only an odor percept, but also a contextual significance that supports appropriate behavioral response to specific odor cues. The piriform cortex serves as a communication hub within this circuit by sharing reciprocal connectivity with higher processing regions, such as the lateral entorhinal cortex and amygdala. The functional significance of these descending inputs on piriform cortical processing of odorants is currently not well understood. We have employed optogenetic methods to selectively stimulate lateral and basolateral amygdala (BLA afferent fibers innervating the posterior piriform cortex (pPCX to quantify BLA modulation of pPCX odor-evoked activity. Single unit odor-evoked activity of anaesthetized BLA-infected animals was significantly modulated compared with control animal recordings, with individual cells displaying either enhancement or suppression of odor-driven spiking. In addition, BLA activation induced a decorrelation of odor-evoked pPCX ensemble activity relative to odor alone. Together these results indicate a modulatory role in pPCX odor processing for the BLA complex, which could contribute to learned changes in PCX activity following associative conditioning.

  3. Prevalence of extended-spectrum cephalosporin-resistant Escherichia coli in a farrowing farm: ST1121 clone harboring IncHI2 plasmid contributes to the dissemination of blaCMY-2

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    Hui eDeng


    Full Text Available Abstract During a regular monitoring of antimicrobial resistance in a farrowing farm in Southern China, 117 Escherichia coli isolates were obtained from sows and piglets. Compared with the isolates from piglets, the isolates from sows exhibited higher resistance rates to the tested cephalosporins. Correspondingly, the total detection rate of the blaCMY-2/blaCTX-M genes in the sow isolates (34.2% was also significantly higher than that of the piglet isolates (13.6% (p<0.05. The blaCMY-2 gene had a relatively high prevalence (11.1% in the E. coli isolates. MLST and PFGE analysis revealed the clonal spread of ST1121 E. coli in most (7/13 of the blaCMY-2-positive isolates. An indistinguishable IncHI2 plasmid harboring blaCMY-2 was also identified in each of the seven ST1121 E. coli isolates. Complete sequence analysis of this IncHI2 plasmid (pEC5207 revealed that pEC5207 may have originated through recombination of an IncHI2 plasmid with a blaCMY-2-carrying IncA/C plasmid like pCFSAN007427_01. In addtion to blaCMY-2, pEC5207 also carried other resistance determinants for aminoglycosides (aacA7, sulfonamides (sul1, as well as heavy metals ions, such as Cu and Ag. The susceptibility testing showed that the pEC5207 can mediate both antibiotic and heavy metal resistance. This highlights the role of pEC5207 in co-selection of blaCMY-2-positive isolates under the selective pressure of heavy metals, cephalosporins and other antimicrobials. In conclusion, clonal spread of an ST1121 type E. coli strain harboring an IncHI2 plasmid contributed to the dissemination of blaCMY-2 in a farrowing farm in Southern China. We also have determined the first complete sequence analysis of a blaCMY-2-carrying IncHI2 plasmid.

  4. Investigation of blaKPC-2 and blaNDM-1 of carbapenem-resistant Enterobacteriaceae%耐碳青霉烯类肠杆菌科细菌KPC-2与NDM-1基因的研究

    Institute of Scientific and Technical Information of China (English)

    谢小芳; 沈海英; 周惠琴; 杨欢; 朱雪明; 杜鸿


    OBJECTIVE To detect the situation of enzyme production in carbapenem-resistance Enterobacteriaceae and the detected blaK PC and blaN DM-1 , and to investigate the mechanism of carbapenem-resistance in Enterobacteriaceae .METHODS The situation of enzyme production in 29 strains of carbapenem-resistance Enterobacteriaceae was detected by modified Hodge test and imipenem-EDTA double-disk synergy test and three-dimensional modified test .blaK PC and blaNDM-1 ,these two carbapenemases-resistance genes were analyzed by PCR and verified by DNA sequencing .RESULTS A total of 26 strains from 29 isolated strains were positive in modified Hodge test ,7 strains positive in imipenem-EDTA double-disk synergy test ,7 strains positive in three-dimensional modified test .There were 16 strains carrying blaK PC carbapenemase-resistant genes ,accounting for 55 .17% and no strains carrying blaNDM-1 carbapenemase-resistant gene .CONCLUSIONS The mechanism of drug resistance of carbapenem-resistant Enterobacteriaceae is mainly due to production of carbapenemase .%目的:检测耐碳青霉烯类抗菌药物肠杆菌科细菌产酶情况以及KPC-2和NDM-1耐药基因的检出,分析耐碳青霉烯类抗菌药物的耐药机制。方法采用改良Hodge试验、亚胺培南-EDTA纸片协同试验和AmpC酶三维试验检测29株耐碳青霉烯类抗菌药物肠杆菌科细菌产酶情况;PCR法检测KPC-2及NDM-1两种碳青霉烯酶耐药基因。结果29株分离菌中26株菌改良Hodge试验阳性,7株亚胺培南-EDTA纸片协同试验阳性,7株AmpC酶三维试验阳性,16株携带KPC-2型碳青霉烯酶耐药基因,占55.17%,未扩增出NDM-1碳青霉烯酶耐药基因。结论耐碳青霉烯类抗菌药物肠杆菌科细菌的耐药机制主要是产碳青霉烯酶。

  5. High prevalence of bla(CTX-M) extended-spectrum β-lactamase genes in Escherichia coli isolates from pets and emergence of CTX-M-64 in China. (United States)

    Sun, Y; Zeng, Z; Chen, S; Ma, J; He, L; Liu, Y; Deng, Y; Lei, T; Zhao, J; Liu, J-H


    As a cause of community-acquired infections, extended-spectrum β-lactamase (ESBL)-producing Escherichia coli constitute an emerging public-health concern. Few data on the molecular epidemiology of ESBL-producing E. coli isolates from pets are available in China. Detection and characterization of ESBL genes (bla(CTX-M), bla(SHV) and bla(TEM)) was conducted among 240 E. coli isolates recovered from healthy and sick pets in South China from 2007 to 2008. The clonal relatedness of ESBL-producing E. coli isolates was assessed by pulsed field gel electrophoresis. ESBL-encoding genes were identified in 97 (40.4%) of the 240 isolates and 96 (40.0%) of them harbored CTX-M. The most common CTX-M types were CTX-M-14 (n = 45) and CTX-M-55 (n = 24). The recently reported CTX-M-64 was identified in three isolates. Isolates producing CTX-M-27, -15, -65, -24, -3 and -9 were also identified. Ten isolates carried two or three CTX-M types, with the combination of CTX-M-14 and CTX-M-55 being the most frequent (n = 6). ISEcp1 was identified in the upstream region of 93 out of the 107 bla(CTX-M) genes (86.9%). The sequence of the spacer region (45 bp) between ISEcp1 and the start codon of all bla(CTX-M-55) genes (except four) was identical to that of bla(CTX-M-64). No major clonal relatedness was observed among these CTX-M producers. It is suggested that the horizontal transfer of bla(CTX-M) genes, mediated by mobile elements, contributes to their dissemination among E. coli isolates from pets. Our finding of high prevalence of ESBL in E. coli of companion animal origin illustrates the importance of molecular surveillance in tracking CTX-M-producing E. coli strains in pets.

  6. Prevalence of ST1193 clone and IncI1/ST16 plasmid in E-coli isolates carrying blaCTX-M-55 gene from urinary tract infections patients in China (United States)

    Xia, Liang; Liu, Yang; Xia, Shu; Kudinha, Timothy; Xiao, Shu-nian; Zhong, Nan-shan; Ren, Guo-sheng; Zhuo, Chao


    To study molecular epidemiology of CTX-M-55-carrying Escherichia coli isolates from urinary tract infections (UTIs) in China. 111 blaCTX-M-55-positive E.coli isolates from UTIs patients in China were studied. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to analyze the homologies among the strains. Conjugation experiments, S1nuclease PFGE and PCR analysis were performed to characterize plasmids harboring blaCTX-M-55 and their genetic environment. 111 isolates were clustered into 86 individual pulsotypes and three clusters by PFGE. Fifty-five (49.5%) of the isolates belonged to 8 STs. Most of the ST1193 isolates belonged to one PFGE cluster. Transconjugants (n = 45) derived from randomly selected blaCTX-M-55 donors (n = 58), were found to contain a single 90-kb conjugative plasmid, which mainly belonged to the IncI1 groups (34, 76%). Among the IncI1 plasmids, the blaCTX-M-55/IncI1/ST16 predominated (23/34, 68%). The blaTEM-1 and aac (3′)-II genes were frequently detected on the IncI1 plasmids, and the insertion of ISEcp1 or IS26 was observed at the 48 bp or 45 bp upstream of the start codon of blaCTX-M-55 gene. The dissemination of blaCTX-M-55 gene among E. coli UTI isolates, appeared to be due to both the major clonal lineage of ST1193 and the horizontal transfer of epidemic plasmid IncI1/ST16. PMID:28338012

  7. War wound treatment complications due to transfer of an IncN plasmid harboring bla(OXA-181) from Morganella morganii to CTX-M-27-producing sequence type 131 Escherichia coli. (United States)

    McGann, Patrick; Snesrud, Erik; Ong, Ana C; Appalla, Lakshmi; Koren, Michael; Kwak, Yoon I; Waterman, Paige E; Lesho, Emil P


    A 22-year-old male developed a recurrent sacral abscess associated with embedded shrapnel following a blast injury. Cultures grew extended-spectrum β-lactamase (ESBL)-producing, carbapenem-susceptible Escherichia coli. Ertapenem was administered, but the infection recurred after each course of antibiotics. Initial surgical interventions were unsuccessful, and subsequent cultures yielded E. coli and Morganella morganii, both nonsusceptible to carbapenems. The isolates were Carba NP test negative, gave ambiguous results with the modified Hodge test, and amplified the bla(OXA48)-like gene by real-time PCR. All E. coli isolates were sequence type 131 (ST131), carried nine resistance genes (including bla(CTX-M-27)) on an IncF plasmid, and were identical by genome sequencing, except for 150 kb of plasmid DNA in carbapenem-nonsusceptible isolates only. Sixty kilobases of this was shared by M. morganii and represented an IncN plasmid harboring bla(OXA-181). In M. morganii, the gene was flanked by IS3000 and ISKpn19, but in all but one of the E. coli isolates containing bla(OXA-181), a second copy of ISKpn19 had inserted adjacent to IS3000. To the best of our knowledge, this is the first report of bla(OXA-181) in the virulent ST131 clonal group and carried by the promiscuous IncN family of plasmids. The tendency of M. morganii to have high MICs of imipenem, a bla(OXA-181) substrate profile that includes penicillins but not extended-spectrum cephalosporins, and weak carbapenemase activity almost resulted in the presence of bla(OXA-181) being overlooked. We highlight the importance of surveillance for carbapenem resistance in all species, even those with intrinsic resistances, and the value of advanced molecular techniques in detecting subtle genetic changes.

  8. Prevalence and characterization of plasmid-mediated blaESBL with their genetic environment in Escherichia coli and Klebsiella pneumoniae in patients with pneumonia

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-rong; CHEN Ji-chao; KANG Yu; JIANG Ning; AN Shu-chang; GAO Zhan-cheng


    Background The extended spectrum β-lactamase (ESBL)-producing Escherichia coli (E.coli) and Klebsiella pneumoniae (K.pneumoniae) are the major pathogens causing pneumonia and have a significant impact on the clinical course.Limited data exist on molecular characterization of ESBL-producing E.coli and K.pneumoniae that cause pneumonia.The aim of this study was to investigate the comprehensive multilevel characteristics of E.coli and K.pneumoniae causing pneumonia in China for the first time.Methods E.coli (17) and K.pneumoniae (21) isolates responsible for pneumonia were isolated from 1270 specimens collected in a prospective multi-center study in eight teaching hospitals in China from June to December in 2007.The susceptibilities,ESBL confirmation,sequence typing,blaCTX-M and blaSHV genes,their genetic environment and plasmid Inc/rep types were determined.Results Sixteen E.coli (94.1%) and eleven K.pneumoniae (52.4%) isolates were ESBL producers.About 77.8% and 66.7% of them were resistance to ciprofloxacin and levofloxacin,and 100% were susceptible to imipenem.The most prevalent ESBL gene was CTX-M-14,followed by SHV-2,CTX-M-15,CTX-M-3,CTX-M-65,SHV-12,SHV-26 and SHV-28.SHV-1 and SHV-11 were also detected and coexisted with blaCTX-Ms in five strains,and three strains contained only SHV-1.All CTX-M-14 were detected ISEcp1 upstream and nine were found IS903 downstream and the majority of them (64.3%) were carried by IncF plasmids.All blasHv were flanked by recFand deoR,located on IncF,IncN,IncX and IncH plasmids.Two SHV-2,one SHV-1 and the only SHV-28 were further preceded by IS26.Genes lacYand lacZwere detected at further upstream of two blaSHv-1.The K.pneumoniae carrying SHV-28 was susceptible to β-lactams,and no mutations or deletions in gene or promoter sequences were identified to account for susceptibility.Multilocus sequence typing experiments showed the ESBL-producing strains were genetically diverse.Conclusions The rate of occurrence of bla

  9. Mechanisms of allergen-antibody interaction of cockroach allergen Bla g 2 with monoclonal antibodies that inhibit IgE antibody binding.

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    Jill Glesner

    Full Text Available BACKGROUND: Cockroach allergy is strongly associated with asthma, and involves the production of IgE antibodies against inhaled allergens. Reports of conformational epitopes on inhaled allergens are limited. The conformational epitopes for two specific monoclonal antibodies (mAb that interfere with IgE antibody binding were identified by X-ray crystallography on opposite sites of the quasi-symmetrical cockroach allergen Bla g 2. METHODOLOGY/PRINCIPAL FINDINGS: Mutational analysis of selected residues in both epitopes was performed based on the X-ray crystal structures of the allergen with mAb Fab/Fab' fragments, to investigate the structural basis of allergen-antibody interactions. The epitopes of Bla g 2 for the mAb 7C11 or 4C3 were mutated, and the mutants were analyzed by SDS-PAGE, circular dichroism, and/or mass spectrometry. Mutants were tested for mAb and IgE antibody binding by ELISA and fluorescent multiplex array. Single or multiple mutations of five residues from both epitopes resulted in almost complete loss of mAb binding, without affecting the overall folding of the allergen. Preventing glycosylation by mutation N268Q reduced IgE binding, indicating a role of carbohydrates in the interaction. Cation-π interactions, as well as electrostatic and hydrophobic interactions, were important for mAb and IgE antibody binding. Quantitative differences in the effects of mutations on IgE antibody binding were observed, suggesting heterogeneity in epitope recognition among cockroach allergic patients. CONCLUSIONS/SIGNIFICANCE: Analysis by site-directed mutagenesis of epitopes identified by X-ray crystallography revealed an overlap between monoclonal and IgE antibody binding sites and provided insight into the B cell repertoire to Bla g 2 and the mechanisms of allergen-antibody recognition, including involvement of carbohydrates.

  10. Development of a direct ELISA based on carboxy-terminal of penicillin-binding protein BlaR for the detection of β-lactam antibiotics in foods. (United States)

    Peng, Juan; Cheng, Guyue; Huang, Lingli; Wang, Yulian; Hao, Haihong; Peng, Dapeng; Liu, Zhenli; Yuan, Zonghui


    β-Lactam antibiotics, including penicillins and cephalosporins, are commonly used in veterinary medicine. Illegal use and abuse of β-lactams could cause allergy and selected bacterial resistance. BlaR-CTD, the carboxy-terminal of penicillin-recognizing protein BlaR from Bacillus licheniformis ATCC 14580, was utilized in this study to develop a receptor-based ELISA for detection and determination of β-lactam antibiotics in milk, beef, and chicken. This assay was based on directly competitive inhibition of binding of horseradish peroxidase-labeled ampicillin to the immobilized BlaR-CTD by β-lactams. The assay was developed as screening test with the option as semiquantitative assay, when the identity of a single type of residual β-lactam was known. The IC50 values of 15 β-lactam antibiotics, including benzylpenicillin, ampicillin, amoxicillin, dicloxacillin, oxacillin, nafcillin, cefapirin, cefoperazone, cefalotin, cefazolin, cefquinome, ceftriaxone, cefotaxime, cefalexin, ceftiofur and its metabolite desfuroylceftiofur were evaluated and ranged from 0.18 to 170.81 μg L(-1). Simple sample extraction method was carried out with only phosphate-buffered saline, and the recoveries of selected β-lactam antibiotics in milk, beef, and chicken were in the range of 53.27 to 128.29 %, most ranging from 60 to 120 %. The inter-assay variability was below 30 %. Limits of detection in milk, beef, and chicken muscles with cefquinome matrix calibration were 2.10, 30.68, and 31.13 μg kg(-1), respectively. This study firstly established a rapid, simple, and accurate method for simultaneous detection of 15 β-lactams in edible tissues, among which 11 β-lactams controlled by European Union could be detected below maximum residue limits.

  11. In vivo Acquisition of Carbapenemase Gene blaKPC-2 in Multiple Species of Enterobacteriaceae through Horizontal Transfer of Insertion Sequence or Plasmid (United States)

    Ding, Baixing; Shen, Zhen; Hu, Fupin; Ye, Meiping; Xu, Xiaogang; Guo, Qinglan; Wang, Minggui


    Objectives: Current worldwide spread of carbapenem resistance in Enterobacteriaceae constitutes a critical public health threat. This study aims to investigate how carbapenem resistance is acquired in Enterobacteriaceae in patients during antimicrobial therapy. Methods: Clinical strains from the same anatomical site of the same patients that converted from carbapenem-susceptible to resistant during antimicrobial therapy and showed identical or similar PFGE patterns were identified. The similarly sized plasmids carried by the susceptible and resistant strains, the latter containing the carbapenemase genes, were sequenced and analyzed. Results: Paired strains were identified from four patients: three had neurosurgical conditions while the other had acute exacerbation of COPD. Two pairs of Klebsiella pneumoniae (KP1-S/R and KP2-S/R, S and R indicating susceptible and resistant strains, respectively), one pair of Morganella morganii (MM-S/R) and one pair of Enterobacter aerogenes (EA-S/R) were collected. All four carbapenem-resistant strains carried plasmids harboring blaKPC−2. Compared with the similarly sized plasmids in KP1-S and KP2-S, an insertion sequence that includes ISKpn6-like, blaKPC−2 and ISKpn8 was noted in pKP1-R and pKP2-R. Strains MM-R and EA-R had blaKPC−2-carrying plasmids not resembling plasmids in strains MM-S and EA-S suggesting their new acquisition while on therapy. Conclusions: Enterobacteriaceae can acquire carbapenem resistance during antimicrobial therapy through horizontal transfer of an insertion sequence or plasmid. PMID:27818649

  12. In Vivo Acquisition of Carbapenemase Gene blaKPC-2 in Multiple Species of Enterobacteriaceae through Horizontal Transfer of Insertion Sequence or Plasmid

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    Baixing Ding


    Full Text Available Objectives: Current worldwide spread of carbapenem resistance in Enterobacteriaceae constitutes a critical public health threat. This study aims to investigate how carbapenem resistance is acquired in Enterobacteriaceae in patients during antimicrobial therapy. Methods: Clinical strains from the same anatomical site of the same patients that converted from carbapenem-susceptible to resistant during antimicrobial therapy and showed identical or similar PFGE patterns were identified. The similarly sized plasmids carried by the susceptible and resistant strains, the latter containing the carbapenemase genes, were sequenced and analyzed. Results: Paired strains were identified from four patients: three had neurosurgical conditions while the other had acute exacerbation of COPD. Two pairs of Klebsiella pneumoniae (KP1-S/R and KP2-S/R, S and R indicating susceptible and resistant strains, respectively, one pair of Morganella morganii (MM-S/R and one pair of Enterobacter aerogenes (EA-S/R were collected. All four carbapenem-resistant strains carried plasmids harboring blaKPC-2. Compared with the similarly sized plasmids in KP1-S and KP2-S, an insertion sequence that includes ISKpn6-like, blaKPC-2 and ISKpn8 was noted in pKP1-R and pKP2-R. Strains MM-R and EA-R had blaKPC-2-carrying plasmids not resembling plasmids in strains MM-S and EA-S suggesting their new acquisition while on therapy. Conclusions: Enterobacteriaceae can acquire carbapenem resistance during antimicrobial therapy through horizontal transfer of an insertion sequence or plasmid.

  13. 产NDM-1型碳青霉烯酶摩根摩根菌的分离及分子背景研究%Isolation and molecular analysis of blaNDM-1-positive Morganella morganii

    Institute of Scientific and Technical Information of China (English)

    王选; 吴晓燕; 李佳萍; 宋国蓉; 邱炳峰; 顾丹霞; 张嵘


    Objective To investigate the molecular background of the New Delhi-metallo-1 (NDM-1)-producing Morganella morganii.Methods Two carbapenem-resistant M.morganii named 1 and 2 were isolated in the Second Hospital of Jiaxing,Zhejiang on October 4th and 29th,respectively.Antimicrobial susceptibility was determined by agar dilution method.Pulsed-field gel electrophoresis (PFGE) was performed to analyse the homololgy of isolates.Amplification with specific primers,DNA sequencing,conjugation experiments and genetic environment analysis were conducted to investigate the molecular mechanisms of resistance.Results The two M.morganii isolates were resistant to carbapenem and fluoroquinolones,while susceptible to aztreonam.PFGE analysis indicated that the two isolates were distinguishable.Amplification and DNA sequencing confirmed the coexistence of blaNDM-1,blasHv-12,qnrS1 and aac(6')-Ib-cr in both isolates.Transconjugants were detected with blaNDM.1 and qnrS1 simultaneously.Genetic environment analysis demonstrated that the blaNDM-1-bleMBL-trpF-dsbC-cutA1 structure was in consistence with those from known blaNDM-1-carrying Klebsiella pneumoniae.Conclusion The blaNDM-1 in M.morganii isolates possiblely obtained from K.pneumoniae through translatable plasmids.%目的 对发现的产新德里金属β内酰胺酶1(NDM-1)型碳青霉烯酶摩根摩根菌进行分子背景研究.方法 两株碳青霉烯类抗生素耐药摩根摩根菌1和2分别于2013年10月4日和10月29日分离自浙江省嘉兴市第二医院.琼脂稀释法测定抗生素敏感性;脉冲场凝胶电泳(PFGE)分析两菌株同源性;特异性PCR扩增和序列分析、接合试验和耐药基因周围序列分析进行菌株耐药机制分子水平研究.结果 2株菌对喹诺酮类和碳青霉烯类抗生素耐药,对氨曲南敏感;PFGE结果显示2株菌非同源;特异性PCR扩增和序列分析发现2株菌同时携带耐药基因blaNDM-1、blaSHV-12、qnrS1和aac(6')-Ib-cr;接合子中同时携带bla

  14. Profiles of phenotype resistance to antibiotic other than β-lactams in Klebsiella pneumoniae ESBLs-producers, carrying blaSHV genes

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    Pawel Sacha


    Full Text Available Extended spectrum β-lactamases production is one of the most common mechanism of resistance to extendedspectrum β-lactam antibiotics is increasing worldwide. Twenty five strains of Klebsiella pneumoniae isolated from clinicalspecimens were tested. Based on the phenotypic confirmatory test all these strains were defined as ESBL producers namedESBL(+. The plasmid DNA from each strains was used to investigate the presence of blaSHV genes responsible for extendedspectrum β-lactamases production. Moreover, susceptibility of these strains to antibiotic other than β-lactams in was tested.

  15. CD3+ and BLA.36+ cells do not occur in the epidermis and adnexal epithelia of normal skin from the dorsolateral trunk of cats. (United States)

    Tranchina, Michelle M; Scott, Danny W; McDonough, Sean P


    A small population of resident T-lymphocytes is present in the normal epidermis of humans, mice, and rats. However, resident epidermal lymphocytes have not been reported in the normal skin of the cat. Skin-biopsy specimens from the normal skin of the dorsolateral trunk from 30 cats were examined histologically and immunohistochemically for the presence of lymphocytes, CD3+ cells, and BLA.36+ cells in epidermis and adnexal epithelia. All examinations were negative. It appears that lymphocytes occur rarely, if at all, in the epidermis and adnexal epithelial of normal cat skin. Hence, the presence of lymphocytes in these structures should be considered abnormal.

  16. The first report of infection with Klebsiella pneumoniae carrying the bla kpc gene in State of Mato Grosso do Sul, Brazil

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    Marilene Rodrigues Chang


    Full Text Available The increased frequency and dissemination of enterobacteria resistant to various antimicrobials is currently worldwide concern. In January 2010, a 94-year-old patient with chronic lymphocytic leukemia was admitted to the University Hospital. This patient died 21 days after hospitalization due to the clinical worsening. Klebsiella pneumoniae producing of extended-spectrum β-lactamases (ESBLs was isolated of urine culture. This bacterium demonstrated resistance to ceftazidime, ciprofloxacin, levofloxacin, ertapenem and imipenem. Susceptibility to cefoxitin, cefepime, meropenem, colistin and tigecycline. This study reports the first case of infection by Klebsiella pneumoniae carrying the bla kpc gene in the State of Mato Grosso do Sul, Brazil.

  17. Characterization of blaTEM-52-carrying plasmids of extended-spectrum-β-lactamase-producing Salmonella enterica isolates from chicken meat with a common supplier in Japan. (United States)

    Matsumoto, Yuko; Izumiya, Hidemasa; Sekizuka, Tsuyoshi; Kuroda, Makoto; Ohnishi, Makoto


    The acquisition of resistance to cephalosporins among Salmonella spp. is a major public health concern. This study identified clonal plasmids carrying bla(TEM-52) from 10 Salmonella enterica serovar Infantis and Manhattan isolates from retail chicken meats that originated from a common supplier in Japan. Whole-genome analyses of the representative plasmids, including pYM4, revealed that they are 38 kb in size and that pYM4 is identical to pDKX1 from beef in Denmark, suggesting a global dissemination of resistance mediated by the plasmids.

  18. The IncP-6 Plasmid p10265-KPC from Pseudomonas aeruginosa Carries a Novel ΔISEc33-Associated bla KPC-2 Gene Cluster


    Dai, Xiaotian; Zhou, Dongsheng; Xiong, Wei; Feng, Jiao; Luo, Wenbo; Luo, Guangming; Wang, Haijing; Sun, Fengjun; Zhou, Xiangdong


    Pseudomonas aeruginosa strain 10265 was recovered from a patient with pneumonia in a Chinese public hospital, and it displays the carbapenem resistance phenotype due to the acquisition of a non-conjugative but mobilizable IncP-6-type plasmid p10265-KPC. p10265-KPC carries a Tn5563-borne defective mer locus, and a novel ΔISEc33-associated bla KPC-2 gene cluster without paired inverted repeats and paired direct repeats at both ends. Mobilization of this ΔISEc33-associated element in p10265-KPC ...

  19. 多重PCR检测食源金黄色葡萄球菌nuc、blaZ和mecA基因方法的建立与应用%Multiplex PCR for detection of nuc, blaZ and mecA genes in food-borne Staphylococcus aureus and its application

    Institute of Scientific and Technical Information of China (English)

    刘书亮; 刘冬香; 贾仁勇; 韩新锋


    目的 建立快速检测食源金黄色葡萄球菌(Sa)耐热核酸酶基因(nuc)、β-内酰胺酶基因(blaZ)和甲氧西林耐药基因(mecA)的多重PCR方法.方法 根据GenBank Sa的nuc、blaZ和mecA基因序列,设计3对特异性引物,建立鉴定Sa及分析Sa耐β-内酰胺类抗生素三重PCR方法,并对79株食源Sa进行基因检测与表型比较.结果 显示供试Sa中检出nuc、blaZ基因阳性率分别为97.47%、73.42%,mecA基因检出为阴性;nuc基因检出与其表型符合率达97.47%;而blaZ扩增结果与β-内酰胺酶试验、青霉素类敏感试验同时符合率为49.37%,前者与后两者符合率分别为60.76%和75.95%;mecA与耐甲氧西林表型符合率为100%;此次79株食源Sa中无耐甲氧西林Sa.结论 该方法简便、快捷、准确,为食源Sa鉴定和耐药性分子分析提供了参考依据.

  20. Complete sequencing of IncI1 sequence type 2 plasmid pJIE512b indicates mobilization of blaCMY-2 from an IncA/C plasmid. (United States)

    Tagg, Kaitlin A; Iredell, Jonathan R; Partridge, Sally R


    Sequencing of pJIE512b, a 92.3-kb IncI1 sequence type 2 (ST2) plasmid carrying bla(CMY-2), revealed a bla(CMY-2) context that appeared to have been mobilized from an IncA/C plasmid by the insertion sequence IS1294. A comparison with published plasmids suggests that bla(CMY-2) has been mobilized from IncA/C to IncI1 plasmids more than once by IS1294-like elements. Alignment of pJIE512b with the only other available IncI1 ST2 plasmid revealed differences across the backbones, indicating variability within this sequence type.

  1. Loop-Mediated Isothermal Amplification untuk Mendeteksi Gen blaTEM sebagai Penyandi Extended-Spectrum Beta-Lactamase pada Isolat Enterobacteriaceae

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    Bayu A. P. Wilopo


    Full Text Available Extended-spectrum beta-lactamase (ESBL is a beta-lactamase enzyme that is capable of hydrolyzing penicillin, cephalosporin, and monobactam, and can be inhibited by clavulanic acid. This enzyme is encoded by multiple genes, one of them is blaTEM. Polymerase chain reaction (PCR is one of the DNA amplification methods that are frequently used; however, there are other methods that can be used including, among others, loop-mediated isothermal amplification (LAMP. LAMP requires simple equipment with quicker and easy-to-read results compared to PCR. This study was a diagnostic test to explore the sensitivity and specificity of LAMP method compared to PCR in detecting blaTEM gene. Furthermore, the concordance between LAMP and PCR methods was assessed. A total of 92 Enterobacteriaceae isolates were examined by PCR and LAMP methods and compared. The result showed that the LAMP method had a sensitivity of 91.4% and a specificity of 91.2% with a concordance value (kappa of 85.4%. In conclusion, LAMP method has a good validity and a very good conformity compared to the PCR method. Therefore, LAMP method can be used as an alternative diagnostic test, especially in limited settings.

  2. Dissemination of multidrug-resistant blaCTX-M-15/IncFIIk plasmids in Klebsiella pneumoniae isolates from hospital- and community-acquired human infections in Tunisia. (United States)

    Mansour, Wejdene; Grami, Raoudha; Ben Haj Khalifa, Anis; Dahmen, Safia; Châtre, Pierre; Haenni, Marisa; Aouni, Mahjoub; Madec, Jean-Yves


    This study investigated the molecular features of extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae from hospital- and community-acquired (HA/CA) infections in the region of Mahdia, Tunisia. Among 336 K. pneumoniae isolates recovered from both clinical contexts between July 2009 and December 2011, 49 and 15 were ESBL producers and originated from clinical and community sources, respectively. All isolates produced the CTX-M-15 enzyme. As shown by Southern blot on S1 nuclease treatment followed by pulsed-field gel electrophoresis (PFGE) gels, the blaCTX-M-15 gene was carried on IncFII (n=4), IncFIIk (n=25), IncL/M (n=4), IncK (n=1), or untypeable (n=15) plasmids in HA isolates. In CA isolates, the blaCTX-M-15 gene was carried on IncFIIk (n=6), IncFII (n=1), IncHI1 (n=1), or untypeable (n=7) plasmids. In all, 23 and 11 PFGE types were found among the HA and CA isolates. Multilocus sequence typing on representative isolates shows diverse sequence types (STs), such as ST307, ST101, ST39, ST4, ST140, ST15, and ST307 in HA isolates and ST101, ST664, and ST323 in CA isolates. This study is the first comprehensive report of ESBL plasmids in K. pneumoniae from HA and CA infections in Tunisia.

  3. Colistin- and Carbapenem-Resistant Escherichia coli Harboring mcr-1 and blaNDM-5, Causing a Complicated Urinary Tract Infection in a Patient from the United States

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    José R. Mediavilla


    Full Text Available Colistin is increasingly used as an antibiotic of last resort for the treatment of carbapenem-resistant Gram-negative infections. The plasmid-borne colistin resistance gene mcr-1 was initially identified in animal and clinical samples from China and subsequently reported worldwide, including in the United States. Of particular concern is the spread of mcr-1 into carbapenem-resistant bacteria, thereby creating strains that approach pan-resistance. While several reports of mcr-1 have involved carbapenem-resistant strains, no such isolates have been described in the United States. Here, we report the isolation and identification of an Escherichia coli strain harboring both mcr-1 and carbapenemase gene blaNDM-5 from a urine sample in a patient without recent travel outside the United States. The isolate exhibited resistance to both colistin and carbapenems, but was susceptible to amikacin, aztreonam, gentamicin, nitrofurantoin, tigecycline, and trimethoprim-sulfamethoxazole. The mcr-1- and blaNDM-5-harboring plasmids were completely sequenced and shown to be highly similar to plasmids previously reported from China. The strain in this report was first isolated in August 2014, highlighting an earlier presence of mcr-1 within the United States than previously recognized.

  4. [blaVIM-2 gene detection in metallo-beta-lactamase-producing Pseudomonas aeruginosa strains isolated in an intensive care unit in Ciudad Bolívar, Venezuela]. (United States)

    Guevara, Armando; de Waard, Jacobus; Araque, María


    Ten Pseudomonas aeruginosa strains with resistance to broad-spectrum cephalosporin and carbapenems were studied to determine the presence of genes that mediate the production of metallo-beta-lactamases. These strains were isolated from patients with nosocomial infection at the Intensive Care Unit of the Complejo Hospitalario "Ruiz y Paéz" of Ciudad Bolívar, Bolívar State, Venezuela, from 2003 to 2006. In all isolates a metallo-enzyme activity was detected by using the double disk synergism test. PCR amplification of genes encoding the families IMP, VIM and SPM metallo-beta-lactamases showed the presence of a blaVIM gene in all strains studied. DNA sequencing revealed that all isolates showed the presence of blaVIM-2. These results suggest that it is necessary to keep these strains under epidemiologic surveillance, establish laboratory strategies for opportune detection and the implementation of new policies to ensure the appropriate use of antibiotics in this institution.

  5. Characterization of Achromobacter Species in Cystic Fibrosis Patients: Comparison of blaOXA-114 PCR Amplification, Multilocus Sequence Typing, and Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry (United States)

    Rodrigues, Elenice R. A.; Ferreira, Alex G.; Leão, Robson S.; Leite, Cassiana C. F.; Carvalho-Assef, Ana Paula; Albano, Rodolpho M.


    Molecular methodologies were used to identify 28 Achromobacter spp. from patients with cystic fibrosis (CF). Multilocus sequence typing (MLST) identified 17 Achromobacter xylosoxidans isolates (all blaOXA-114 positive), nine Achromobacter ruhlandii isolates (all blaOXA-114 positive), one Achromobacter dolens isolate, and one Achromobacter insuavis isolate. All less common species were misidentified as A. xylosoxidans by matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). Chronic colonization by clonally related A. ruhlandii isolates was demonstrated. PMID:26400790

  6. Antibiotic-resistant Klebsiella pneumoniae and Escherichia coli high-risk clones and an IncFII(k) mosaic plasmid hosting Tn1 (blaTEM-4) in isolates from 1990 to 2004. (United States)

    Rodríguez, Irene; Novais, Ângela; Lira, Felipe; Valverde, Aránzazu; Curião, Tânia; Martínez, José Luis; Baquero, Fernando; Cantón, Rafael; Coque, Teresa M


    We describe the genetic background of bla(TEM-4) and the complete sequence of pRYC11::bla(TEM-4), a mosaic plasmid that is highly similar to pKpQIL-like variants, predominant among TEM-4 producers in a Spanish hospital (1990 to 2004), which belong to Klebsiella pneumoniae and Escherichia coli high-risk clones responsible for the current spread of different antibiotic resistance genes. Predominant populations of plasmids and host adapted clonal lineages seem to have greatly contributed to the spread of resistance to extended-spectrum cephalosporins.

  7. Use of WGS data for investigation of a long-term NDM-1-producing Citrobacter freundii outbreak and secondary in vivo spread of blaNDM-1 to Escherichia coli, Klebsiella pneumoniae and Klebsiella oxytoca

    DEFF Research Database (Denmark)

    Hammerum, Anette M; Hansen, Frank; Linde Nielsen, Hans


    Objectives An outbreak of NDM-1-producing Citrobacter freundii and possible secondary in vivo spread of blaNDM-1 to other Enterobacteriaceae were investigated. Methods From October 2012 to March 2015, meropenem-resistant Enterobacteriaceae were detected in 45 samples from seven patients at Aalbor...

  8. Molecular characterization of the bla(KPC-2) gene in clinical isolates of carbapenem-resistant Klebsiella pneumoniae from the pediatric wards of a Chinese hospital. (United States)

    Liu, Yang; Li, Xiang-Yang; Wan, La-Gen; Jiang, Wei-Yan; Li, Fang-Qu; Yang, Jing-Hong


    The present study was conducted to confirm the presence of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae associated with a nosocomial outbreak in a Chinese pediatric hospital. From July 2009 to January 2011, 124 nonduplicated K. pneumoniae isolates were collected from specimens from patients of pediatric units in the hospital. Twelve of the 124 isolates possessed the bla(KPC-2) gene and showed 7 different pulsed-field gel electrophoresis (PFGE) patterns. Meanwhile, 16S rRNA methylase, acc(6')-Ib-cr, and several types of β-lactamases were also produced by the majority of the KPC-producing isolates. Class 1 integron-encoded intI1 integrase gene was subsequently found in all strains, and amplification, sequencing, and comparison of DNA between 5' conserved segment and 3' conserved segment region showed the presence of several known antibiotic resistance gene cassettes of various sizes. The conjugation and plasmid-curing experiments indicated some KPC-2-encoding genes were transmissible. In addition, conjugal cotransfer of multidrug-resistant phenotypes with KPC-positive phenotypes was observed in KPC-producing strains. Restriction endonuclease analysis and DNA hybridization with a KPC-specific probe showed that the bla(KPC-2) gene was carried by plasmid DNA from K. pneumoniae of PFGE pattern B. The overall results indicate that the emergence and outbreak of KPC-producing K. pneumoniae in our pediatric wards occurred in conjunction with plasmids coharboring 16S rRNA methylase and extended-spectrum β-lactamases.

  9. 鲍曼不动杆菌多位点序列分型及 blaOXA-51-like基因的基因型分析%Multilocus sequence typing of Acinetobacter baumanni strains and the distribution of blaOXA-51-like genes in those isolates in Guangzhou

    Institute of Scientific and Technical Information of China (English)

    李裕军; 潘楚芝; 郭鹏豪; 赵子文; 赵祝香; 方昌全; 陈惠玲


    目的:对广州地区3家教学医院的鲍曼不动杆菌菌株进行分子流行病学分型及blaOXA-51-like基因的基因型分析,以了解鲍曼不动杆菌菌群结构及流行菌株。方法收集非重复鲍曼不动杆菌52株,多位点序列分型(MLST)进行分子分型,eBURST分析菌株亲缘性,将序列型(STs)归类为克隆复合体(CC), PCR扩增blaOXA-51-like基因全长并测序确定blaOXA-51-like基因型。结果 MLST将52株鲍曼不动杆菌分为5个已有ST型及7个新ST型,其中STn4包含新发现的gpi位点的等位基因G1,其与gpi 111的差别在于第3个碱基的T→C突变,STn5包含新发现的gltA的等位基因A1,其与gltA 1的差别在于第156位碱基的A→C突变及159位碱基的A→C突变。 ST195及ST208最常见,占到了总数的69.2%, eBURST分析显示其属于CC92。52株菌株中只有1株携带OXA-199,其余51株菌株均携带OXA-66。结论鲍曼不动杆菌CC92在广州地区广泛流行,携带OXA-66基因。%Objective To investigate the distribution of blaOXA-51-like genes and the clonal relation-ship among Acinetobacter baumannii strains isolated from three teaching hospitals in Guangzhou , China. Methods Fifty-two Acinetobacter baumannii isolates were genotyped by multilocus sequence typing (MLST).eBURST algorithm was performed to define clonal complexes (CCs).blaOXA-51-like genes were am-plified by using polymerase chain reaction ( PCR) and sequenced .Results MLST grouped the A.bauman-nii isolates into 5 existing sequence types (STs) and 7 new STs.STn4 carried allele G1 with a T→C muta-tion at the 3rd nucleotide site (nt3) on the gpi111 locus.STn5 carried allele A1, possessing A→C muta-tions at nt156 and nt159 on the gltA1 locus.ST195 and ST208 accounted for 69.2%of all isolates.Clonal relationship analysis showed that ST 195 and ST208 belonged to CC92.Fifty-one A.baumannii isolates car-ried OXA-66 and the rest one carried OXA-199.Conclusion A

  10. 肠道定植产KPC酶植生拉乌尔菌的耐药基因环境分析%Genetic Environment of blaKPC-2 in the Intestinal Colonized Raoultella planticolas

    Institute of Scientific and Technical Information of China (English)



    The increasing emergence and spread of Klebsiella pneumoniae carbapenemases ( KPCs ) leaves fewer available therapeutic options due to their broad-spectrum hydrolytic activity. Two KPC-2-producing Raoultella planticola isolates were first identified and analyzed using PCR, Southern hybridization and sequencing in China. Two isolates had an identical antimicrobial susceptibility profile, blaKPC-2 gene as well as its flanking sequences. They were resistant to 16 antimicrobial agents while sensitive to polymyxin B, colistin and minocycline. The results demonstrated that the blaKPC-2 gene was located on a 7 498 bp plasmid segment that encoded five open reading frames with the order of Tn3-transposase, Tn3-resolvase, ISKpn8, blaKPC-2 gene and ISKpn6-like.%碳青霉烯酶编码基因的传播是临床抗菌治疗面临的严重威胁之一。采用PCR、Southern杂交、测序比对等方法筛查和研究了碳青霉烯类抗菌药物的相关耐药基因。首次在国内发现了产KPC酸的植生拉乌尔菌两株。分离到的植生拉乌尔菌对被测试的19种常用抗菌药物中的16种耐药,只对多粘菌素B、粘菌素和米诺环素敏感。它们均产KPC-2型碳青霉烯酶,其编码基因blaKPC-2位于质粒上,两侧(包括blaKPC-2)长度为7498 bp的DNA序列所包含的结构从上游至下游分别为Tn3-transposase, Tn3-resolvase, ISKpn8, blaKPC-2和ISKpn6-like元件。

  11. Complete Sequence of a F33:A-:B- Conjugative Plasmid Carrying the oqxAB, fosA3 and blaCTX-M-55 Elements from a Foodborne Escherichia coli Strain

    Directory of Open Access Journals (Sweden)

    Marcus Ho-yin Wong


    Full Text Available This study reports the complete sequence of pE80, a conjugative IncFII plasmid recovered from an E. coli strain isolated from chicken meat. This plasmid harbors multiple resistance determinants including oqxAB, fosA3, blaCTX-M-55 and blaTEM-1, and is a close variant of the recently reported p42-2 element, which was recovered from E. coli of veterinary source. Recovery of pE80 constitutes evidence that evolution or genetic re-arrangement of IncFII type plasmids residing in animal-borne organisms is an active event, which involves acquisition and integration of foreign resistance elements into the plasmid backbone. Dissemination of these plasmids may further compromise the effectiveness of current antimicrobial strategies.

  12. Complete Genome Sequence of a Human-Invasive Salmonella enterica Serovar Typhimurium Strain of the Emerging Sequence Type 213 Harboring a Multidrug Resistance IncA/C Plasmid and a blaCMY-2-Carrying IncF Plasmid. (United States)

    Silva, Claudia; Calva, Edmundo; Calva, Juan J; Wiesner, Magdalena; Fernández-Mora, Marcos; Puente, José L; Vinuesa, Pablo


    Salmonella enterica subsp. enterica serovar Typhimurium strain 33676 was isolated in Mexico City, Mexico, from a patient with a systemic infection, and its complete genome sequence was determined using PacBio single-molecule real-time technology. Strain 33676 harbors an IncF plasmid carrying the extended-spectrum cephalosporin gene blaCMY-2 and a multidrug resistance IncA/C plasmid.

  13. Differential role of muscarinic transmission within the entorhinal cortex and basolateral amygdala in the processing of irrelevant stimuli. (United States)

    Barak, Segev; Weiner, Ina


    Cholinergic projections to the entorhinal cortex (EC) and basolateral amygdala (BLA) mediate distinct cognitive processes through muscarinic acetylcholine receptors (mAChRs). In this study, we sought to further differentiate the role of muscarinic transmission in these regions in cognition, using the latent inhibition (LI) phenomenon. LI is a cross-species phenomenon manifested as poorer conditioning to a stimulus experienced as irrelevant during an earlier stage of repeated non-reinforced pre-exposure to that stimulus, and is considered to index the ability to ignore, or to in-attend to, irrelevant stimuli. Given our recent findings that systemic administration of the mAChR antagonist scopolamine can produce two contrasting LI abnormalities in rats, ie, abolish LI under conditions yielding LI in non-treated controls, or produce abnormally persistent LI under conditions preventing its expression in non-treated controls, we tested whether mAChR blockade in the EC and BLA would induce LI abolition and persistence, respectively. We found that intra-EC scopolamine infusion (1, 10 mug per hemisphere) abolished LI when infused in pre-exposure or both pre-exposure and conditioning, but not in conditioning alone, whereas intra-BLA scopolamine infusion led to persistent LI when infused in conditioning or both stages, but not in pre-exposure alone. Although cholinergic innervation of the EC and BLA has long been implicated in attention to novel stimuli and in processing of motivationally significant stimuli, respectively, our results provide evidence that EC mAChRs also have a role in the development of inattention to stimuli, whereas BLA mAChRs have a role in re-attending to previously irrelevant stimuli that became motivationally relevant.

  14. First detection of AmpC β-lactamase bla(CMY-2) on a conjugative IncA/C plasmid in a Vibrio parahaemolyticus isolate of food origin. (United States)

    Li, Ruichao; Lin, Dachuan; Chen, Kaichao; Wong, Marcus Ho Yin; Chen, Sheng


    Vibrio parahaemolyticus is an important causative agent of gastroenteritis, with the consumption of contaminated seafood being the major transmission route. Resistance to penicillin is common among V. parahaemolyticus strains, whereas cephalosporin resistance remains rare. In an attempt to assess the current prevalence and characteristics of antibiotic resistance of this pathogen in common food samples, a total of 54 (17% of the total samples) V. parahaemolyticus strains were isolated from 318 meat and seafood samples purchased from supermarkets and wet markets in Shenzhen, China, in 2013. These isolates exhibited high-level resistance to ampicillin, yet they were mostly susceptible to other antimicrobials, except for two that were resistant to extended-spectrum cephalosporins. The β-lactamase gene blaPER-1 was detectable in one strain, V. parahaemolyticus V43, which was resistant to both third- and fourth-generation cephalosporins. Compared to other blaPER-1-positive V. parahaemolyticus strains reported in our previous studies, strain V43 was found to harbor an ∼200-kb conjugative plasmid carrying genes that were different from the antimicrobial resistance genes reported from the previous studies. The β-lactamase gene blaCMY-2 was detectable for the first time in another V. parahaemolyticus isolate, V4, which was resistant to third-generation cephalosporins. This blaCMY-2 gene was shown to be located in an ∼150-kb IncA/C-type conjugative plasmid with a genetic structure consisting of traB-traV-traA-ISEcp1-blaCMY-2-blc-sugE-encR-orf1-orf2-orf3-orf4-dsbC-traC, which is identical to that of other IncA/C conjugative plasmids in Enterobacteriaceae, albeit with a different size. These findings indicate that the transmission of extended-spectrum-β-lactamase (ESBL) and AmpC β-lactamase genes via conjugative plasmids can mediate the development of extended-spectrum cephalosporin resistance in V. parahaemolyticus, thereby posing a potential threat to public health.

  15. Occurrence of blaCTX-M-1, qnrB1 and virulence genes in avian ESBL-producing Escherichia coli isolates from Tunisia (United States)

    Kilani, Hajer; Abbassi, Mohamed Salah; Ferjani, Sana; Mansouri, Riadh; Sghaier, Senda; Ben Salem, Rakia; Jaouani, Imen; Douja, Gtari; Brahim, Sana; Hammami, Salah; Ben Chehida, Noureddine; Boubaker, Ilhem Boutiba-Ben


    Avian ESBL-producing Escherichia coli isolates have been increasingly reported worldwide. Animal to human dissemination, via food chain or direct contact, of these resistant bacteria has been reported. In Tunisia, little is known about avian ESBL- producing E. coli and further studies are needed. Seventeen ESBL-producing Escherichia coli isolates from poultry feces from two farms (Farm 1 and farm 2) in the North of Tunisia have been used in this study. Eleven of these isolates (from farm 1) have the same resistance profile to nalidixic acid, sulfonamides, streptomycin, tetracycline, and norfloxacine (intermediately resistant). Out of the six isolates recovered from farm 2, only one was co-resistant to tetracycline. All isolates, except one, harbored blaCTX-M-1 gene, and one strain co-harbored the blaTEM-1 gene. The genes tetA and tetB were carried, respectively, by 11 and 1 amongst the 12 tetracycline-resistant isolates. Sulfonamides resistance was encoded by sul1, sul2, and sul3 genes in 3, 17, and 5 isolates, respectively. The qnrB1 was detected in nine strains, one of which co-harbored qnrS1 gene. The search for the class 1 and 2 integrons by PCR showed that in farm 1, class 1 and 2 integrons were found in one and ten isolates, respectively. In farm 2, class 1 integron was found in only one isolate, class 2 was not detected. Only one gene cassette arrangement was demonstrated in the variable regions (VR) of the 10 int2-positive isolates: dfrA1- sat2-aadA1. The size of the VR of the class 1 integron was approximately 250 bp in one int1-positive isolate, whereas in the second isolate, no amplification was observed. All isolates of farm 1 belong to the phylogroup A (sub-group A0). However, different types of phylogroups in farm 2 were detected. Each of the phylogroups A1, B22, B23 was detected in one strain, while the D2 phylogroup was found in 3 isolates. The virulence genes iutA, fimH, and traT were detected in 3, 7, and 3 isolates, respectively. Two types of

  16. Occurrence of bla CTX-M-1, qnrB1 and virulence genes in avian ESBL-producing Escherichia coli isolates from Tunisia. (United States)

    Kilani, Hajer; Abbassi, Mohamed Salah; Ferjani, Sana; Mansouri, Riadh; Sghaier, Senda; Ben Salem, Rakia; Jaouani, Imen; Douja, Gtari; Brahim, Sana; Hammami, Salah; Ben Chehida, Noureddine; Boubaker, Ilhem Boutiba-Ben


    Avian ESBL-producing Escherichia coli isolates have been increasingly reported worldwide. Animal to human dissemination, via food chain or direct contact, of these resistant bacteria has been reported. In Tunisia, little is known about avian ESBL- producing E. coli and further studies are needed. Seventeen ESBL-producing Escherichia coli isolates from poultry feces from two farms (Farm 1 and farm 2) in the North of Tunisia have been used in this study. Eleven of these isolates (from farm 1) have the same resistance profile to nalidixic acid, sulfonamides, streptomycin, tetracycline, and norfloxacine (intermediately resistant). Out of the six isolates recovered from farm 2, only one was co-resistant to tetracycline. All isolates, except one, harbored bla CTX-M-1 gene, and one strain co-harbored the bla TEM-1 gene. The genes tetA and tetB were carried, respectively, by 11 and 1 amongst the 12 tetracycline-resistant isolates. Sulfonamides resistance was encoded by sul1, sul2, and sul3 genes in 3, 17, and 5 isolates, respectively. The qnrB1 was detected in nine strains, one of which co-harbored qnrS1 gene. The search for the class 1 and 2 integrons by PCR showed that in farm 1, class 1 and 2 integrons were found in one and ten isolates, respectively. In farm 2, class 1 integron was found in only one isolate, class 2 was not detected. Only one gene cassette arrangement was demonstrated in the variable regions (VR) of the 10 int2-positive isolates: dfrA1- sat2-aadA1. The size of the VR of the class 1 integron was approximately 250 bp in one int1-positive isolate, whereas in the second isolate, no amplification was observed. All isolates of farm 1 belong to the phylogroup A (sub-group A0). However, different types of phylogroups in farm 2 were detected. Each of the phylogroups A1, B22, B23 was detected in one strain, while the D2 phylogroup was found in 3 isolates. The virulence genes iutA, fimH, and traT were detected in 3, 7, and 3 isolates, respectively. Two types of

  17. Transcriptome mapping of pAR060302, a blaCMY-2-positive broad-host-range IncA/C plasmid. (United States)

    Lang, Kevin S; Danzeisen, Jessica L; Xu, Wayne; Johnson, Timothy J


    The multidrug resistance-encoding plasmids belonging to the IncA/C incompatibility group have recently emerged among Escherichia coli and Salmonella enterica strains in the United States. These plasmids have a unique genetic structure compared to other enterobacterial plasmid types, a broad host range, and a propensity to acquire large numbers of antimicrobial resistance genes via their accessory regions. Using E. coli strain DH5α harboring the prototype IncA/C plasmid pAR060302, we sought to define the baseline transcriptome of IncA/C plasmids under laboratory growth and in the face of selective pressure. The effects of ampicillin, florfenicol, or streptomycin exposure were compared to those on cells left untreated at logarithmic phase using Illumina platform-based RNA sequencing (RNA-Seq). Under growth in Luria-Bertani broth lacking antibiotics, much of the backbone of pAR060302 was transcriptionally inactive, including its putative transfer regions. A few plasmid backbone genes of interest were highly transcribed, including genes of a putative toxin-antitoxin system and an H-NS-like transcriptional regulator. In contrast, numerous genes within the accessory regions of pAR060302 were highly transcribed, including the resistance genes floR, bla(CMY-2), aadA, and aacA. Treatment with ampicillin or streptomycin resulted in no genes being differentially expressed compared to controls lacking antibiotics, suggesting that many of the resistance-associated genes are not differentially expressed due to exposure to these antibiotics. In contrast, florfenicol treatment resulted in the upregulation of floR and numerous chromosomal genes. Overall, the transcriptome mapping of pAR060302 suggests that it mitigates the fitness costs of carrying resistance-associated genes through global regulation with its transcriptional regulators.

  18. Clinical Specimen-Direct LAMP: A Useful Tool for the Surveillance of blaOXA-23-Positive Carbapenem-Resistant Acinetobacter baumannii. (United States)

    Yamamoto, Norihisa; Hamaguchi, Shigeto; Akeda, Yukihiro; Santanirand, Pitak; Kerdsin, Anusak; Seki, Masafumi; Ishii, Yoshikazu; Paveenkittiporn, Wantana; Bonomo, Robert A; Oishi, Kazunori; Malathum, Kumthorn; Tomono, Kazunori


    Healthcare-associated infections are a leading cause of morbidity and mortality worldwide. Treatment is increasingly complicated by the escalating incidence of antimicrobial resistance. Among drug-resistant pathogens, carbapenem-resistant Acinetobacter baumannii (CRAb) is of increasing concern because of the limited applicable therapies and its expanding global distribution in developed countries and newly industrialized countries. Therefore, a rapid detection method that can be used even in resource-poor countries is urgently required to control this global public health threat. Conventional techniques, such as bacterial culture and polymerase chain reaction (PCR), are insufficient to combat this threat because they are time-consuming and laborious. In this study, we developed a loop-mediated isothermal amplification (LAMP) method for detecting blaOXA-23-positive CRAb, the most prevalent form of CRAb in Asia, especially in Thailand, and confirmed its efficacy as a surveillance tool in a clinical setting. Clinical samples of sputum and rectal swabs were collected from patients in a hospital in Bangkok and used for LAMP assays. After boiling and centrifugation, the supernatants were used directly in the assay. In parallel, a culture method was used for comparison purposes to evaluate the specificity and sensitivity of LAMP. As a first step, a total of 120 sputum samples were collected. The sensitivity of LAMP was 88.6% (39/44), and its specificity was 92.1% (70/76) using the culture method as the "gold standard". When surveillance samples including sputum and rectal swabs were analyzed with the LAMP assay, its sensitivity was 100.0%. This method enables the direct analysis of clinical specimens and provides results within 40 minutes of sample collection, making it a useful tool for surveillance even in resource-poor countries.

  19. Clinical Specimen-Direct LAMP: A Useful Tool for the Surveillance of blaOXA-23-Positive Carbapenem-Resistant Acinetobacter baumannii.

    Directory of Open Access Journals (Sweden)

    Norihisa Yamamoto

    Full Text Available Healthcare-associated infections are a leading cause of morbidity and mortality worldwide. Treatment is increasingly complicated by the escalating incidence of antimicrobial resistance. Among drug-resistant pathogens, carbapenem-resistant Acinetobacter baumannii (CRAb is of increasing concern because of the limited applicable therapies and its expanding global distribution in developed countries and newly industrialized countries. Therefore, a rapid detection method that can be used even in resource-poor countries is urgently required to control this global public health threat. Conventional techniques, such as bacterial culture and polymerase chain reaction (PCR, are insufficient to combat this threat because they are time-consuming and laborious. In this study, we developed a loop-mediated isothermal amplification (LAMP method for detecting blaOXA-23-positive CRAb, the most prevalent form of CRAb in Asia, especially in Thailand, and confirmed its efficacy as a surveillance tool in a clinical setting. Clinical samples of sputum and rectal swabs were collected from patients in a hospital in Bangkok and used for LAMP assays. After boiling and centrifugation, the supernatants were used directly in the assay. In parallel, a culture method was used for comparison purposes to evaluate the specificity and sensitivity of LAMP. As a first step, a total of 120 sputum samples were collected. The sensitivity of LAMP was 88.6% (39/44, and its specificity was 92.1% (70/76 using the culture method as the "gold standard". When surveillance samples including sputum and rectal swabs were analyzed with the LAMP assay, its sensitivity was 100.0%. This method enables the direct analysis of clinical specimens and provides results within 40 minutes of sample collection, making it a useful tool for surveillance even in resource-poor countries.

  20. Connectivity processes and riparian vegetation of the upper Paraná River, Brazil (United States)

    Stevaux, José C.; Corradini, Fabrício A.; Aquino, Samia


    In fluvial systems, the relationship between a dominant variable (e.g. flood pulse) and its dependent ones (e.g. riparian vegetation) is called connectivity. This paper analyzes the connectivity elements and processes controlling riparian vegetation for a reach of the upper Paraná River (Brazil) and estimates the future changes in channel-vegetation relationship as a consequence of the managing of a large dam. The studied reach is situated 30 km downstream from the Porto Primavera Dam (construction finished in 1999). Through aerial photography (1:25,000, 1996), RGB-CBERS satellite imagery and a previous field botany survey it was possible to elaborate a map with the five major morpho-vegetation units: 1) Tree-dominated natural levee, 2) Shrubby upper floodplain, 3) Shrub-herbaceous mid floodplain, 4) Grass-herbaceous lower floodplain and 5) Shrub-herbaceous flood runoff channel units. By use of a detailed topographic survey and statistical tools each morpho-vegetation type was analyzed according to its connectivity parameters (frequency, recurrence, permanence, seasonality, potamophase, limnophase and FCQ index) in the pre- and post-dam closure periods of the historical series. Data showed that most of the morpho-vegetation units were predicted to present changes in connectivity parameters values after dam closing and the new regime could affect, in different intensity, the river ecology and particularly the riparian vegetation. The methods used in this study can be useful for dam impact studies in other South American tropical rivers.

  1. Characterisation of IncA/C2 plasmids carrying an In416-like integron with the blaVIM-19 gene from Klebsiella pneumoniae ST383 of Greek origin. (United States)

    Papagiannitsis, Costas C; Dolejska, Monika; Izdebski, Radosław; Giakkoupi, Panagiota; Skálová, Anna; Chudějová, Kateřina; Dobiasova, Hana; Vatopoulos, Alkiviadis C; Derde, Lennie P G; Bonten, Marc J M; Gniadkowski, Marek; Hrabák, Jaroslav


    The complete nucleotide sequences of three multidrug resistance (MDR) IncA/C-like plasmids from Enterobacteriaceae isolates carrying the VIM-type carbapenemase-encoding integrons In4863 (blaVIM-19-aacA7-dfrA1-ΔaadA1-smr2) or In4873 (blaVIM-1-aacA7-dfrA1-ΔaadA1-smr2) were determined, which are the first In416-like elements identified in Greece. Plasmids pKP-Gr642 and pKP-Gr8143 were from Klebsiella pneumoniae ST383 isolates, whereas plasmid pEcl-Gr4873 was from an Enterobacter cloacae ST88 isolate. Sequencing showed that pKP-Gr642 (162787bp) and pKP-Gr8143 (154395bp) consisted of the type 1 IncA/C2 conserved backbone, the blaCMY-2-like gene-containing region, and the ARI-B (with the sul2 gene) and ARI-A (with a class 1 integron) resistance islands, like the plasmid pUMNK88_161 from the USA. The third plasmid, pEcl-Gr4873 (153958bp), exhibited extensive similarity with the type 2 IncA/C2 plasmid pR55 from France. pEcl-Gr4873 carried only one resistance island of a hybrid transposon structure inserted in a different location to ARI-A in type 1 A/C2 plasmids. In all three plasmids, the In416-like integrons In4863 or In4873 were identified within non-identical class II transposon structures. All three In416-like-carrying regions presented significant similarities with the MDR region of the IncA/C2 plasmid pCC416 from Italy, carrying the prototype In416 integron (blaVIM-4-aacA7-dfrA1-ΔaadA1-smr2). These findings provided the basis for speculations regarding the evolution of IncA/C2 plasmids with In416-like integrons, and confirmed the rapid evolution of some IncA/C2 plasmid lineages. Considering the broad host range of IncA/C2 molecules, it seems that pKP-Gr642, pKP-Gr8143 and pEcl-Gr4873 plasmids might support the diffusion of In416-like integrons among Enterobacteriaceae.

  2. Routes of Synthesis of Carbapenems for Optimizing Both the Inactivation of L,D-Transpeptidase LdtMt1 of Mycobacterium tuberculosis and the Stability toward Hydrolysis by β-Lactamase BlaC. (United States)

    Iannazzo, Laura; Soroka, Daria; Triboulet, Sébastien; Fonvielle, Matthieu; Compain, Fabrice; Dubée, Vincent; Mainardi, Jean-Luc; Hugonnet, Jean-Emmanuel; Braud, Emmanuelle; Arthur, Michel; Etheve-Quelquejeu, Mélanie


    Combinations of β-lactams of the carbapenem class, such as meropenem, with clavulanate, a β-lactamase inhibitor, are being evaluated for the treatment of drug-resistant tuberculosis. However, carbapenems approved for human use have never been optimized for inactivation of the unusual β-lactam targets of Mycobacterium tuberculosis or for escaping to hydrolysis by broad-spectrum β-lactamase BlaC. Here, we report three routes of synthesis for modification of the two side chains carried by the β-lactam and the five-membered rings of the carbapenem core. In particular, we show that the azide-alkyne Huisgen cycloaddition reaction catalyzed by copper(I) is fully compatible with the highly unstable β-lactam ring of carbapenems and that the triazole ring generated by this reaction is well tolerated for inactivation of the L,D-transpeptidase LdtMt1 target. Several of our new carbapenems are superior to meropenem both with respect to the efficiency of in vitro inactivation of LdtMt1 and reduced hydrolysis by BlaC.

  3. Chromosomal location of the fosA3 and blaCTX-M genes in Proteus mirabilis and clonal spread of Escherichia coli ST117 carrying fosA3-positive IncHI2/ST3 or F2:A-:B- plasmids in a chicken farm. (United States)

    He, Dandan; Liu, Lanping; Guo, Baowei; Wu, Shengjun; Chen, Xiaojie; Wang, Jing; Zeng, Zhenling; Liu, Jian-Hua


    The aim of this study was to investigate the spread and location of the fosA3 gene among Enterobacteriaceae from diseased broiler chickens. Twenty-nine Escherichia coli and seven Proteus mirabilis isolates recovered from one chicken farm were screened for the presence of plasmid-mediated fosfomycin resistance genes by PCR. The clonal relatedness of fosA3-positive isolates, the transferability and location of fosA3, and the genetic context of the fosA3 gene were determined. Seven P. mirabilis isolates with three different pulsed-field gel electrophoresis (PFGE) patterns and five E. coli isolates belonging to sequence type 117 (ST117) and phylogenetic group D were positive for fosA3 and all carried the blaCTX-M gene. In E. coli, the genetic structures IS26-ISEcp1-blaCTX-M-65-IS26-fosA3-1758 bp-IS26 and IS26-ISEcp1-blaCTX-M-3-blaTEM-1-IS26-fosA3-1758 bp-IS26 were present on transferable IncHI2/ST3 and F2:A-:B- plasmids, respectively. However, fosA3 was located on the chromosome of the seven P. mirabilis isolates. IS26-ISEcp1-blaCTX-M-65-IS26-fosA3-1758 bp-IS26 and IS26-blaCTX-M-14-611 bp-fosA3-1222 bp-IS26 were detected in three and four P. mirabilis isolates, respectively. Minicircles that contained both fosA3 and blaCTX-M-65 were shared between E. coli and P. mirabilis. This is the first report of the fosA3 gene integrated into the chromosome of P. mirabilis isolates with the blaCTX-M gene. The emergence and clonal spread of avian pathogenic E. coli ST117 with the feature of multidrug resistance and high virulence are a serious problem.

  4. Nye oplysninger om bl.a. miljømæssig risikovurdering af PAT-protein og glufosinatammonium herbicider. Zea mays (Bt11). Supplerende materiale om Bt11. Modtaget 21-02-2005, deadline 29-03-2005, svar 07-03-2005

    DEFF Research Database (Denmark)

    Strandberg, Morten Tune


    Mail: Det tilsendte supplerende materiale om Bt-11 majsen (mail pr. 21-02-2005) omhandler bl.a. eventuelle uønskede konsekvenser ved ulovlig anvendelse af glufosinat ammonium herbicider i forbindelse med dyrkningen. Vi har allerede indraget dette aspekt i forbindelse med den økologiske risikovurd...

  5. Detection of staphylococcal cassette chromosome mec type XI carrying highly divergent mecA, mecI, mecR1, blaZ, and ccr genes in human clinical isolates of clonal complex 130 methicillin-resistant Staphylococcus aureus.

    LENUS (Irish Health Repository)

    Shore, Anna C


    Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec (SCCmec) elements. In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. The isolates were identified as methicillin-susceptible S. aureus using the GeneXpert real-time PCR assay. Whole-genome sequencing of one isolate (M10\\/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ-mecA-mecR1-mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). The SCCmec element was almost identical to that of SCCmec type XI (SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The open reading frames (ORFs) identified within SCCmec XI of M10\\/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. A third DR was identified ca. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. aureus strains were predominantly from bovine sources. The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon.

  6. Antimicrobial resistance and extended-spectrum β-lactamases of Salmonella enterica serotypes isolated from livestock and processed food in Portugal: an update. (United States)

    Figueiredo, Rui; Henriques, Ana; Sereno, Rui; Mendonça, Nuno; da Silva, Gabriela Jorge


    As Salmonella is a common foodborne pathogen, the present study aimed to determine the distribution of Salmonella enterica serotypes isolated during 2011-2012 from poultry, swine, cattle, and processed food in Portugal, and to characterize the antimicrobial susceptibility and the extended-spectrum β-lactamases (ESBLs). Results were also compared with data obtained before the implementation of the National Control Program in Poultry and the ban of antimicrobial agents in animal feed in the European Union (EU). A total of 14 serotypes were identified, from 258 isolates recovered, with Salmonella Typhimurium (32.6%, n=84) and Salmonella Enteritidis (10.1%, n=26) being the most common. Salmonella Enteritidis in poultry was less frequent than in previous studies, which might be associated with the implementation of the National Control Program for Salmonella in poultry. Nevertheless, other serotypes seem to occupy this biological niche, and may be more common in human salmonellosis in the future. The majority of isolates (70.2%, n=181) were resistant to at least one class of antimicrobial agent and exhibited higher frequency of resistance to tetracycline (47.7%, n=123) and ampicillin (36.0%, n=93), with Salmonella Typhimurium being the more resistant serotype. Resistance to fluoroquinolones was shown in 8% (n=21) of isolates, a lower value compared to data obtained before 2004. ESBLs producers Salmonella Typhimurium bla(CTX-M-1) and Salmonella Enteritidis bla(SHV-12) were isolated from swine and poultry, respectively. The bla(CTX-M-1) and bla(SHV-12) genes were carried on conjugative plasmids of IncHI2replicon types and IncI1, respectively. This was the first report of a bla(CTX-M-1) in Salmonella Typhimurium in Portugal. Overall, the results revealed changes in animal origin Salmonella serotypes, mainly emerging serotypes, in frequency of resistance, and in occurrence of ESBLs-producing Salmonella. The control measures taken by the EU seem to have some impact on the

  7. Reconsolidation and extinction are dissociable and mutually exclusive processes: behavioral and molecular evidence. (United States)

    Merlo, Emiliano; Milton, Amy L; Goozée, Zara Y; Theobald, David E; Everitt, Barry J


    Memory persistence is critically influenced by retrieval. In rats, a single presentation of a conditioned fear stimulus induces memory reconsolidation and fear memory persistence, while repeated fear cue presentations result in loss of fear through extinction. These two opposite behavioral outcomes are operationally linked by the number of cue presentations at memory retrieval. However, the behavioral properties and mechanistic determinants of the transition have not yet been explored; in particular, whether reconsolidation and extinction processes coexist or are mutually exclusive, depending on the exposure to non-reinforced retrieval events. We characterized both behaviorally and molecularly the transition from reconsolidation to extinction of conditioned fear and showed that an increase in calcineurin (CaN) in the basolateral amygdala (BLA) supports the shift from fear maintenance to fear inhibition. Gradually increasing the extent of retrieval induces a gradual decrease in freezing responses to the conditioned stimulus and a gradual increase in amygdala CaN level. This newly synthesized CaN is required for the extinction, but not the reconsolidation, of conditioned fear. During the transition from reconsolidation to extinction, we have revealed an insensitive state of the fear memory where NMDA-type glutamate receptor agonist and antagonist drugs are unable either to modulate CaN levels in the BLA or alter the reconsolidation or extinction processes. Together, our data indicate both that reconsolidation and extinction are mutually exclusive processes and also reveal the presence of a transitional, or "limbo," state of the original memory between these two alternative outcomes of fear memory retrieval, when neither process is engaged.

  8. Analysis of the observation of particle detector inside ‘CBERS-1’ satellite under solar quiet conditions

    Institute of Scientific and Technical Information of China (English)

    ZOU; Hong; XIAO; Zuo; HAO; Yongqiang; ZOU; Jiqing; ZHU; Wenming; WU; Zhongxiang


    Based on the knowledge and related theory of earth's radiation belt, the data chronous orbit were analyzed. It is proved that the observational results are in agreement with the theoretical description of the radiation belt structures. Analysis of more than 3years' data showed clearly that under quiet solar conditions, at a height of about 800 km the energetic particles were mainly located in three regions: northern auroral belt (40°-80°), southern auroral belt (-40°- -80°) and South Atlantic Geomagnetic Anomaly Region (SAA). Actually, this is for the global distribution, at each longitude the latitudinal coverage is much narrower and particles are along the geomagnetic latitude of about ±60°.The species of particles in different regions and their counting rates are different. In SAA,usually both electrons and protons are observed, which should come from inner radiation belt; in polar regions only energetic electrons are observed under the quiet condition,which belongs to the outer radiation belt. The distribution of outer radiation electrons is asymmetrical for longitudes as well as northern and southern polar regions. These asymmetries can be explained with the reflecting altitudes of the mirror points of charged particles at the same L shell.

  9. The discussion of different varieties of remote sensing images' frequent applying and essentials of processing in the forestry's daily work%浅谈林业工作中常用的遥感影像及处理要点

    Institute of Scientific and Technical Information of China (English)



    在遥感影像定义的基础之上,讨论了遥感影像的四个基本特征。对林业工作中常用的中分辨率遥感影像Landsate TM5、中巴资源卫星以及常用的高分辨率遥感影像Spot5、Rapideye、Alos、QuickBird、WorldviewⅠ、WorldviewⅡ等进行了介绍并做了对比分析,总结各种遥感影像的优缺点;并讨论了遥感影像基础数据准备,DOM与DEM参考数据准备以及的遥感影像正射纠正,并以ALOS为例,对算法及图像增强等工作进行了探讨。%According to the definition of remote sensing images (RSI) , four basic characteristics have been disscussed. Mid-resolution varieties of RSI that include Landsate TM5 and CBERS, and high-resolution varieties of RSI that include SpotS, Rapideye, Alos, QuickBird, Worldview I , Worldview II etc.,which have been introduced and frequently applied in inspection work of forestry. This article concluded merits and drawbacks of different varieties of RSI via comparing and analyzing based on mid-resolution and high-resolution varieties of RSI. Meanwhile, basic data's preparation of RSI, DOM and DEM, ortho-rectification.of RSI have been discussed. At last, taking Alos as a case, discussion and research of RSI's processing, enhancement and algorithm have been done as well.

  10. Primary Processing

    NARCIS (Netherlands)

    Mulder, W.J.; Harmsen, P.F.H.; Sanders, J.P.M.; Carre, P.; Kamm, B.; Schoenicke, P.


    Primary processing of oil-containing material involves pre-treatment processes, oil recovery processes and the extraction and valorisation of valuable compounds from waste streams. Pre-treatment processes, e.g. thermal, enzymatic, electrical and radio frequency, have an important effect on the oil r

  11. Elektrokemiske Processer

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers


    Electrochemical processes in: Power sources, Electrosynthesis, Corrosion.Pourbaix-diagrams.Decontamination of industrial waste water for heavy metals.......Electrochemical processes in: Power sources, Electrosynthesis, Corrosion.Pourbaix-diagrams.Decontamination of industrial waste water for heavy metals....

  12. Data processing

    CERN Document Server

    Fry, T F


    Data Processing discusses the principles, practices, and associated tools in data processing. The book is comprised of 17 chapters that are organized into three parts. The first part covers the characteristics, systems, and methods of data processing. Part 2 deals with the data processing practice; this part discusses the data input, output, and storage. The last part discusses topics related to systems and software in data processing, which include checks and controls, computer language and programs, and program elements and structures. The text will be useful to practitioners of computer-rel

  13. High Prevalence of Extended-Spectrum β-Lactamase, Plasmid-Mediated AmpC, and Carbapenemase Genes in Pet Food (United States)

    Seiffert, Salome N.; Carattoli, Alessandra; Tinguely, Regula; Lupo, Agnese; Perreten, Vincent


    We evaluated the pet food contained in 30 packages as a potential origin of extended-spectrum cephalosporin-resistant Gram-negative organisms and β-lactamase genes (bla). Live bacteria were not detected by selective culture. However, PCR investigations on food DNA extracts indicated that samples harbored the blaCTX-M-15 (53.3%), blaCMY-4 (20%), and blaVEB-4-like (6.7%) genes. Particularly worrisome was the presence of blaOXA-48-like carbapenemases (13.3%). The original pet food ingredients and/or the production processes were highly contaminated with bacteria carrying clinically relevant acquired bla genes. PMID:25092703

  14. Detection of Staphylococcal Cassette Chromosome mec Type XI Carrying Highly Divergent mecA, mecI, mecR1, blaZ, and ccr Genes in Human Clinical Isolates of Clonal Complex 130 Methicillin-Resistant Staphylococcus aureus▿† (United States)

    Shore, Anna C.; Deasy, Emily C.; Slickers, Peter; Brennan, Grainne; O'Connell, Brian; Monecke, Stefan; Ehricht, Ralf; Coleman, David C.


    Methicillin resistance in staphylococci is mediated by penicillin binding protein 2a (PBP 2a), encoded by mecA on mobile staphylococcal cassette chromosome mec (SCCmec) elements. In this study, two clonal complex 130 (CC130) methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients in Irish hospitals were identified that were phenotypically PBP 2a positive but lacked mecA by conventional PCR and by DNA microarray screening. The isolates were identified as methicillin-susceptible S. aureus using the GeneXpert real-time PCR assay. Whole-genome sequencing of one isolate (M10/0061) revealed a 30-kb SCCmec element encoding a class E mec complex with highly divergent blaZ-mecA-mecR1-mecI, a type 8 cassette chromosome recombinase (ccr) complex consisting of ccrA1-ccrB3, an arsenic resistance operon, and flanking direct repeats (DRs). The SCCmec element was almost identical to that of SCCmec type XI (SCCmec XI) identified by the Sanger Institute in sequence type 425 bovine MRSA strain LGA251 listed on the website of the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements. The open reading frames (ORFs) identified within SCCmec XI of M10/0061 exhibited 21 to 93% amino acid identity to ORFs in GenBank. A third DR was identified ca. 3 kb downstream of SCCmec XI, indicating the presence of a possible SCC remnant. SCCmec XI was also identified in the second CC130 MRSA isolate by PCR and sequencing. The CC130 MRSA isolates may be of animal origin as previously reported CC130 S. aureus strains were predominantly from bovine sources. The highly divergent nature of SCCmec XI relative to other SCCmec elements indicates that it may have originated in another taxon. PMID:21636525

  15. Design Processes

    DEFF Research Database (Denmark)

    Ovesen, Nis


    advantages and challenges of agile processes in mobile software and web businesses are identified. The applicability of these agile processes is discussed in re- gards to design educations and product development in the domain of Industrial Design and is briefly seen in relation to the concept of dromology......Inspiration for most research and optimisations on design processes still seem to focus within the narrow field of the traditional design practise. The focus in this study turns to associated businesses of the design professions in order to learn from their development processes. Through interviews...

  16. Magnetics Processing (United States)

    Federal Laboratory Consortium — The Magnetics Processing Lab equipped to perform testing of magnetometers, integrate them into aircraft systems, and perform data analysis, including noise reduction...

  17. Stochastic processes

    CERN Document Server

    Parzen, Emanuel


    Well-written and accessible, this classic introduction to stochastic processes and related mathematics is appropriate for advanced undergraduate students of mathematics with a knowledge of calculus and continuous probability theory. The treatment offers examples of the wide variety of empirical phenomena for which stochastic processes provide mathematical models, and it develops the methods of probability model-building.Chapter 1 presents precise definitions of the notions of a random variable and a stochastic process and introduces the Wiener and Poisson processes. Subsequent chapters examine

  18. Image processing

    NARCIS (Netherlands)

    Heijden, van der F.; Spreeuwers, L.J.; Blanken, H.M.; Vries de, A.P.; Blok, H.E.; Feng, L


    The field of image processing addresses handling and analysis of images for many purposes using a large number of techniques and methods. The applications of image processing range from enhancement of the visibility of cer- tain organs in medical images to object recognition for handling by industri

  19. Sustainable processing

    DEFF Research Database (Denmark)

    Kristensen, Niels Heine


    Kristensen_NH and_Beck A: Sustainable processing. In Otto Schmid, Alexander Beck and Ursula Kretzschmar (Editors) (2004): Underlying Principles in Organic and "Low-Input Food" Processing - Literature Survey. Research Institute of Organic Agriculture FiBL, CH-5070 Frick, Switzerland. ISBN 3-906081-58-3...

  20. Process mining

    DEFF Research Database (Denmark)

    van der Aalst, W.M.P.; Rubin, V.; Verbeek, H.M.W.


    Process mining includes the automated discovery of processes from event logs. Based on observed events (e.g., activities being executed or messages being exchanged) a process model is constructed. One of the essential problems in process mining is that one cannot assume to have seen all possible...... behavior. At best, one has seen a representative subset. Therefore, classical synthesis techniques are not suitable as they aim at finding a model that is able to exactly reproduce the log. Existing process mining techniques try to avoid such “overfitting” by generalizing the model to allow for more...... behavior. This generalization is often driven by the representation language and very crude assumptions about completeness. As a result, parts of the model are “overfitting” (allow only for what has actually been observed) while other parts may be “underfitting” (allowfor much more behavior without strong...

  1. Organizing Process

    DEFF Research Database (Denmark)

    Hull Kristensen, Peer; Bojesen, Anders

    This paper invites to discuss the processes of individualization and organizing being carried out under what we might see as an emerging regime of change. The underlying argumentation is that in certain processes of change, competence becomes questionable at all times. The hazy characteristics...... of this regime of change are pursued through a discussion of competencies as opposed to qualifications illustrated by distinct cases from the Danish public sector in the search for repetitive mechanisms. The cases are put into a general perspective by drawing upon experiences from similar change processes...

  2. Electrochemical Processes

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers


    The notes describe in detail primary and secondary galvanic cells, fuel cells, electrochemical synthesis and electroplating processes, corrosion: measurments, inhibitors, cathodic and anodic protection, details of metal dissolution reactions, Pourbaix diagrams and purification of waste water from...

  3. Processing Proteases

    DEFF Research Database (Denmark)

    Ødum, Anders Sebastian Rosenkrans

    Processing proteases are proteases which proteolytically activate proteins and peptides into their biologically active form. Processing proteases play an important role in biotechnology as tools in protein fusion technology. Fusion strategies where helper proteins or peptide tags are fused...... to the protein of interest are an elaborate method to optimize expression or purification systems. It is however critical that fusion proteins can be removed and processing proteases can facilitate this in a highly specific manner. The commonly used proteases all have substrate specificities to the N...... of few known proteases to have substrate specificity for the C-terminal side of the scissile bond. LysN exhibits specificity for lysine, and has primarily been used to complement trypsin in to proteomic studies. A working hypothesis during this study was the potential of LysN as a processing protease...

  4. Grants Process (United States)

    The NCI Grants Process provides an overview of the end-to-end lifecycle of grant funding. Learn about the types of funding available and the basics for application, review, award, and on-going administration within the NCI.

  5. Sewer Processes

    DEFF Research Database (Denmark)

    Hvitved-Jacobsen, Thorkild; Vollertsen, Jes; Nielsen, Asbjørn Haaning

    and valuable information on the sewer as a chemical and biological reactor. It focuses on how to predict critical impacts and control adverse effects. It also provides an integrated description of sewer processes in modeling terms. This second edition is full of illustrative examples and figures, includes...... microbial and chemical processes and demonstrates how this knowledge can be applied for the design, operation, and the maintenance of wastewater collection systems. The authors add chemical and microbial dimensions to the design and management of sewer networks with an overall aim of improved sustainability...... by hydrogen sulfide and other volatile organic compounds, as well as other potential health issues, have caused environmental concerns to rise. Reflecting the most current developments, Sewer Processes: Microbial and Chemical Process Engineering of Sewer Networks, Second Edition, offers the reader updated...

  6. In process...


    LI Xin


    Architecture is a wonderful world. As a student of architecture, time and time again I am inpressed by its powerful imagines. The more I study and learn, however, the more I question. What is the truth beyond those fantastic imagines? What is the nuture of Architecture? Is there any basic way or process to approach the work of Architecture? With these questions, I begin my thesis project and the process of looking for answers. MArch

  7. In process...


    LI Xin


    Architecture is a wonderful world. As a student of architecture, time and time again I am inpressed by its powerful imagines. The more I study and learn, however, the more I question. What is the truth beyond those fantastic imagines? What is the nuture of Architecture? Is there any basic way or process to approach the work of Architecture? With these questions, I begin my thesis project and the process of looking for answers.

  8. Renewal processes

    CERN Document Server

    Mitov, Kosto V


    This monograph serves as an introductory text to classical renewal theory and some of its applications for graduate students and researchers in mathematics and probability theory. Renewal processes play an important part in modeling many phenomena in insurance, finance, queuing systems, inventory control and other areas. In this book, an overview of univariate renewal theory is given and renewal processes in the non-lattice and lattice case are discussed. A pre-requisite is a basic knowledge of probability theory.

  9. Macdonald processes

    CERN Document Server

    Borodin, Alexei


    Macdonald processes are probability measures on sequences of partitions defined in terms of nonnegative specializations of the Macdonald symmetric functions and two Macdonald parameters q,t in [0,1). We prove several results about these processes, which include the following. (1) We explicitly evaluate expectations of a rich family of observables for these processes. (2) In the case t=0, we find a Fredholm determinant formula for a q-Laplace transform of the distribution of the last part of the Macdonald-random partition. (3) We introduce Markov dynamics that preserve the class of Macdonald processes and lead to new "integrable" 2d and 1d interacting particle systems. (4) In a large time limit transition, and as q goes to 1, the particles of these systems crystallize on a lattice, and fluctuations around the lattice converge to O'Connell's Whittaker process that describe semi-discrete Brownian directed polymers. (5) This yields a Fredholm determinant for the Laplace transform of the polymer partition function...

  10. Offshoring Process

    DEFF Research Database (Denmark)

    Slepniov, Dmitrij; Sørensen, Brian Vejrum; Katayama, Hiroshi


    The purpose of this chapter is to contribute to the knowledge on how production offshoring and international operations management vary across cultural contexts. The chapter attempts to shed light on how companies approach the process of offshoring in different cultural contexts. In order...... of globalisation. Yet there are clear differences in how offshoring is conducted in Denmark and Japan. The main differences are outlined in a framework and explained employing cultural variables. The findings lead to a number of propositions suggesting that the process of offshoring is not simply a uniform...

  11. Kontrol og dynamik i pædagogiske processer

    DEFF Research Database (Denmark)

    Ahrenkiel, Annegrethe

    Afhandlingen kombinerer kritisk diskursanalyse (Fairclough) med Basil Bernsteins uddannelsessociologi mhp. at belyse, hvordan læring hhv. fremmes og hæmmes i pædagogisk praksis. Empirisk vises det bl.a. med en tekstnær, lingvistisk analyse af en klasserumssamtale fra en daghøjskole. Afhandlingen...

  12. Processing Branches

    DEFF Research Database (Denmark)

    Schindler, Christoph; Tamke, Martin; Tabatabai, Ali;


    Angled and forked wood – a desired material until 19th century, was swept away by industrialization and its standardization of processes and materials. Contemporary information technology has the potential for the capturing and recognition of individual geometries through laser scanning and compu...

  13. Innovation process

    DEFF Research Database (Denmark)

    Kolodovski, A.


    Purpose of this report: This report was prepared for RISO team involved in design of the innovation system Report provides innovation methodology to establish common understanding of the process concepts and related terminology The report does not includeRISO- or Denmark-specific cultural, economic...


    Directory of Open Access Journals (Sweden)

    Anamarija Kutlić


    Full Text Available Bentonite has vide variety of uses. Special use of bentonite, where its absorbing properties are employed to provide water-tight sealing is for an underground repository in granites In this paper, bentonite processing and beneficiation are described.

  15. Optical Processing. (United States)


    34perceptron" (F. Rosenblatt, Principles of Neurodynamics ), workers in the neural network field have been seeking to understand how neural networks can perform...Moscow). 13. F. Rosenblatt, Principles of Neurodynamics , (Spartan, 1962). 14. W. Stoner "Incoherent optical processing via spatially offset pupil

  16. Protherics公司向美FDA递交Voraxaze的BLA

    Institute of Scientific and Technical Information of China (English)




  17. Ultrastructural Changes in Clinical and Microbiota Isolates of Klebsiella pneumoniae Carriers of Genes bla SHV, bla TEM, bla CTX-M, or bla KPC When Subject to β-Lactam Antibiotics. (United States)

    Veras, Dyana Leal; Lopes, Ana Catarina de Souza; da Silva, Grasielle Vaz; Gonçalves, Gabriel Gazzoni Araújo; de Freitas, Catarina Fernandes; de Lima, Fernanda Cristina Gomes; Maciel, Maria Amélia Vieira; Feitosa, Ana Paula Sampaio; Alves, Luiz Carlos; Brayner, Fábio André


    The aim of this study was to characterize the ultrastructural effects caused by β-lactam antibiotics in Klebsiella pneumoniae isolates. Three K. pneumoniae clinical isolates were selected for the study with resistance profiles for third-generation cephalosporins, aztreonam, and/or imipenem and with different resistance genes for extended-spectrum β-lactamases (ESBL) or Klebsiella pneumoniae carbapenemase (KPC). Two K. pneumoniae isolates obtained from the microbiota, which were both resistant to amoxicillin and ampicillin, were also analyzed. In accordance with the susceptibility profile, the clinical isolates were subjected to subminimum inhibitory concentrations (sub-MICs) of cefotaxime, ceftazidime, aztreonam, and imipenem and the isolates from the microbiota to ampicillin and amoxicillin, for analysis by means of scanning and transmission electron microscopy. The K. pneumoniae isolates showed different morphological and ultrastructural changes after subjection to β-lactams tested at different concentrations, such as cell filamentation, loss of cytoplasmic material, and deformation of dividing septa. Our results demonstrate that K. pneumoniae isolates harboring different genes that encode for β-lactamases show cell alterations when subjected to different β-lactam antibiotics, thus suggesting that they possess residual activity in vitro, despite the phenotypic resistance presented in the isolates analyzed.

  18. Antibiotic resistance spread potential in urban wastewater effluents disinfected by UV/H2O2 process. (United States)

    Ferro, Giovanna; Guarino, Francesco; Castiglione, Stefano; Rizzo, Luigi


    Urban wastewater treatment plants (UWTPs) are among the main hotspots of antibiotic resistance (AR) spread into the environment and the role of conventional and new disinfection processes as possible barrier to minimise the risk for AR transfer is presently under investigation. Accordingly, the aim of this work was to evaluate the effect of an advanced oxidation process (AOP) (specifically UV/H2O2) on AR transfer potential. UV/H2O2 disinfection experiments were carried out on real wastewater samples to evaluate the: i) inactivation of total coliforms, Escherichia coli and antibiotic resistant E. coli as well as ii) possible removal of target antibiotic resistance genes (ARGs) (namely, blaTEM, qnrS and tetW). In particular, DNA was extracted from both antibiotic resistant E. coli bacterial cells (intracellular DNA), grown on selective culture media, and the whole water suspension (total DNA) collected at different treatment times. Polymerase chain reaction (PCR) assay was performed to detect the absence/presence of the selected ARGs. Real Time quantitative Polymerase Chain Reaction (qPCR) was used to quantify the investigated ARGs in terms of copiesmL(-1). In spite of the bacterial inactivation and a decrease of ARGs in intracellular DNA after 60min treatment, UV/H2O2 process was not effective in ARGs removal from water suspension (total DNA). Particularly, an increase up to 3.7×10(3)copiesmL(-1) (p>0.05) of blaTEM gene was observed in total DNA after 240min treatment, while no difference (p>0.05) was found for qnrS gene between the initial (5.1×10(4)copiesmL(-1)) and the final sample (4.3×10(4)copiesmL(-1)). On the base of the achieved results, the investigated disinfection process may not be effective in minimising AR spread potential into the environment. The death of bacterial cells, which results in DNA release in the treated water, may pose a risk for AR transfer to other bacteria present in the receiving water body.

  19. Photobiomodulation Process

    Directory of Open Access Journals (Sweden)

    Yang-Yi Xu


    Full Text Available Photobiomodulation (PBM is a modulation of laser irradiation or monochromatic light (LI on biosystems. There is little research on PBM dynamics although its phenomena and mechanism have been widely studied. The PBM was discussed from dynamic viewpoint in this paper. It was found that the primary process of cellular PBM might be the key process of cellular PBM so that the transition rate of cellular molecules can be extended to discuss the dose relationship of PBM. There may be a dose zone in which low intensity LI (LIL at different doses has biological effects similar to each other, so that biological information model of PBM might hold. LIL may self-adaptively modulate a chronic stress until it becomes successful.

  20. Boolean process

    Institute of Scientific and Technical Information of China (English)

    闵应骅; 李忠诚; 赵著行


    Boolean algebra successfully describes the logical behavior of a digital circuit, and has been widely used in electronic circuit design and test With the development of high speed VLSIs it is a drawback for Boolean algebra to be unable to describe circuit timing behavior. Therefore a Boolean process is defined as a family of Boolean van ables relevant to the time parameter t. A real-valued sample of a Boolean process is a waveform. Waveform functions can be manipulated formally by using mathematical tools. The distance, difference and limit of a waveform polynomial are defined, and a sufficient and necessary condition of the limit existence is presented. Based on this, the concept of sensitization is redefined precisely to demonstrate the potential and wide application possibility The new definition is very different from the traditional one, and has an impact on determining the sensitizable paths with maximum or minimum length, and false paths, and then designing and testing high performance circuits

  1. Purification process

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, A.


    A process for the removal of hydrogen sulphide from gases or liquid hydrocarbons, comprises contacting the gas or liquid hydrocarbon with an aqueous alkaline solution, preferably having a pH value of 8 to 10, comprising (A) an anthraquinone disulphonic acid or a water-soluble sulphonamide thereof (B) a compound of a metal which can exist in at least two valency states and (C) a sequestering agent.

  2. Ceramic Processing

    Energy Technology Data Exchange (ETDEWEB)



    Ceramics represent a unique class of materials that are distinguished from common metals and plastics by their: (1) high hardness, stiffness, and good wear properties (i.e., abrasion resistance); (2) ability to withstand high temperatures (i.e., refractoriness); (3) chemical durability; and (4) electrical properties that allow them to be electrical insulators, semiconductors, or ionic conductors. Ceramics can be broken down into two general categories, traditional and advanced ceramics. Traditional ceramics include common household products such as clay pots, tiles, pipe, and bricks, porcelain china, sinks, and electrical insulators, and thermally insulating refractory bricks for ovens and fireplaces. Advanced ceramics, also referred to as ''high-tech'' ceramics, include products such as spark plug bodies, piston rings, catalyst supports, and water pump seals for automobiles, thermally insulating tiles for the space shuttle, sodium vapor lamp tubes in streetlights, and the capacitors, resistors, transducers, and varistors in the solid-state electronics we use daily. The major differences between traditional and advanced ceramics are in the processing tolerances and cost. Traditional ceramics are manufactured with inexpensive raw materials, are relatively tolerant of minor process deviations, and are relatively inexpensive. Advanced ceramics are typically made with more refined raw materials and processing to optimize a given property or combination of properties (e.g., mechanical, electrical, dielectric, optical, thermal, physical, and/or magnetic) for a given application. Advanced ceramics generally have improved performance and reliability over traditional ceramics, but are typically more expensive. Additionally, advanced ceramics are typically more sensitive to the chemical and physical defects present in the starting raw materials, or those that are introduced during manufacturing.

  3. Hydrocarbon processing

    Energy Technology Data Exchange (ETDEWEB)

    Hill, S.G.; Seddon, D.


    A process for the catalytic conversion of synthesis-gas into a product which comprises naphtha, kerosene and distillate is characterized in that the catalyst is a Fischer-Tropsch catalyst also containing a zeolite, the naphtha fraction contains 60% or less linear paraffins and the kerosene and distillated fractions contain more linear paraffins and olefins than found in the naphtha fraction. Reduction of the relative amount of straight chain material in the naphtha fraction increases the octane number and so enhances the quality of the gasoline product, while the high quality of the kerosene and distillate fractions is maintained.

  4. Crystallization process (United States)

    Adler, Robert J.; Brown, William R.; Auyang, Lun; Liu, Yin-Chang; Cook, W. Jeffrey


    An improved crystallization process is disclosed for separating a crystallizable material and an excluded material which is at least partially excluded from the solid phase of the crystallizable material obtained upon freezing a liquid phase of the materials. The solid phase is more dense than the liquid phase, and it is separated therefrom by relative movement with the formation of a packed bed of solid phase. The packed bed is continuously formed adjacent its lower end and passed from the liquid phase into a countercurrent flow of backwash liquid. The packed bed extends through the level of the backwash liquid to provide a drained bed of solid phase adjacent its upper end which is melted by a condensing vapor.

  5. Lithospheric processes

    Energy Technology Data Exchange (ETDEWEB)

    Baldridge, W. [and others


    The authors used geophysical, geochemical, and numerical modeling to study selected problems related to Earth's lithosphere. We interpreted seismic waves to better characterize the thickness and properties of the crust and lithosphere. In the southwestern US and Tien Shari, crust of high elevation is dynamically supported above buoyant mantle. In California, mineral fabric in the mantle correlate with regional strain history. Although plumes of buoyant mantle may explain surface deformation and magmatism, our geochemical work does not support this mechanism for Iberia. Generation and ascent of magmas remains puzzling. Our work in Hawaii constrains the residence of magma beneath Hualalai to be a few hundred to about 1000 years. In the crust, heat drives fluid and mass transport. Numerical modeling yielded robust and accurate predictions of these processes. This work is important fundamental science, and applies to mitigation of volcanic and earthquake hazards, Test Ban Treaties, nuclear waste storage, environmental remediation, and hydrothermal energy.

  6. Image Processing (United States)


    Electronic Imagery, Inc.'s ImageScale Plus software, developed through a Small Business Innovation Research (SBIR) contract with Kennedy Space Flight Center for use on space shuttle Orbiter in 1991, enables astronauts to conduct image processing, prepare electronic still camera images in orbit, display them and downlink images to ground based scientists for evaluation. Electronic Imagery, Inc.'s ImageCount, a spin-off product of ImageScale Plus, is used to count trees in Florida orange groves. Other applications include x-ray and MRI imagery, textile designs and special effects for movies. As of 1/28/98, company could not be located, therefore contact/product information is no longer valid.

  7. Dynamic Processes (United States)

    Klingshirn, C.

    . Phys. Lett. 92:211105, 2008). For this point, recall Figs. 6.16 and 6.33. Since the polarisation amplitude is gone in any case after the recombination process, there is an upper limit for T 2 given by T 2 ≤ 2 T1. The factor of two comes from the fact that T 2 describes the decay of an amplitude and T 1 the decay of a population, which is proportional to the amplitude squared. Sometimes T 2 is subdivided in a term due to recombination described by T 1 and another called 'pure dephasing' called T 2 ∗ with the relation 1 / T 2 = 1 / 2 T 1 + 1 / T2 ∗. The quantity T 2 ∗ can considerably exceed 2 T 1. In the part on relaxation processes that is on processes contributing to T 3, we give also examples for the capture of excitons into bound, localized, or deep states. For more details on dynamics in semiconductors in general see for example, the (text-) books [Klingshirn, Semiconductor Optics, 3rd edn. (Springer, Berlin, 2006); Haug and Koch, Quantum Theory of the Optical and Electronic Properties of Semiconductors, 4th edn. (World Scientific, Singapore, 2004); Haug and Jauho, Quantum Kinetics in Transport and Optics of Semiconductors, Springer Series in Solid State Sciences vol. 123 (Springer, Berlin, 1996); J. Shah, Ultrafast Spectroscopy of Semiconductors and of Semiconductor Nanostructures, Springer Series in Solid State Sciences vol. 115 (Springer, Berlin, 1996); Schafer and Wegener, Semiconductor Optics and Transport Phenomena (Springer, Berlin, 2002)]. We present selected data for free, bound and localized excitons, biexcitons and electron-hole pairs in an EHP and examples for bulk materials, epilayers, quantum wells, nano rods and nano crystals with the restriction that - to the knowledge of the author - data are not available for all these systems, density ranges and temperatures. Therefore, we subdivide the topic below only according to the three time constants T 2, T 3 and T 1.

  8. Data Processing (United States)

    Grangeat, P.

    A new area of biology has been opened up by nanoscale exploration of the living world. This has been made possible by technological progress, which has provided the tools needed to make devices that can measure things on such length and time scales. In a sense, this is a new window upon the living world, so rich and so diverse. Many of the investigative methods described in this book seek to obtain complementary physical, chemical, and biological data to understand the way it works and the way it is organised. At these length and time scales, only dedicated instrumentation could apprehend the relevant phenomena. There is no way for our senses to observe these things directly. One important field of application is molecular medicine, which aims to explain the mechanisms of life and disease by the presence and quantification of specific molecular entities. This involves combining information about genes, proteins, cells, and organs. This in turn requires the association of instruments for molecular diagnosis, either in vitro, e.g., the microarray or the lab-on-a-chip, or in vivo, e.g., probes for molecular biopsy, and tools for molecular imaging, used to localise molecular information in living organisms in a non-invasive way. These considerations concern both preclinical research for drug design and human medical applications. With the development of DNA and RNA chips [1], genomics has revolutionised investigative methods for cells and cell processes [2,3]. By sequencing the human genome, new ways have been found for understanding the fundamental mechanisms of life [4]. A revolution is currently under way with the analysis of the proteome [5-8], i.e., the complete set of proteins that can be found in some given biological medium, such as the blood plasma. The goal is to characterise certain diseases by recognisable signatures in the proteomic profile, as determined from a blood sample or a biopsy, for example [9-13]. What is at stake is the early detection of

  9. Information Processing - Administrative Data Processing (United States)

    Bubenko, Janis

    A three semester, 60-credit course package in the topic of Administrative Data Processing (ADP), offered in 1966 at Stockholm University (SU) and the Royal Institute of Technology (KTH) is described. The package had an information systems engineering orientation. The first semester focused on datalogical topics, while the second semester focused on the infological topics. The third semester aimed to deepen the students’ knowledge in different parts of ADP and at writing a bachelor thesis. The concluding section of this paper discusses various aspects of the department’s first course effort. The course package led to a concretisation of our discipline and gave our discipline an identity. Our education seemed modern, “just in time”, and well adapted to practical needs. The course package formed the first concrete activity of a group of young teachers and researchers. In a forty-year perspective, these people have further developed the department and the topic to an internationally well-reputed body of knowledge and research. The department has produced more than thirty professors and more than one hundred doctoral degrees.

  10. Technology transfer and scale-up of the Flublok recombinant hemagglutinin (HA) influenza vaccine manufacturing process. (United States)

    Buckland, Barry; Boulanger, Robert; Fino, Mireli; Srivastava, Indresh; Holtz, Kathy; Khramtsov, Nikolai; McPherson, Clifton; Meghrous, Jamal; Kubera, Paul; Cox, Manon M J


    Multiple different hemagglutinin (HA) protein antigens have been reproducibly manufactured at the 650L scale by Protein Sciences Corporation (PSC) based on an insect cell culture with baculovirus infection. Significantly, these HA protein antigens were produced by the same Universal Manufacturing process as described in the biological license application (BLA) for the first recombinant influenza vaccine approved by the FDA (Flublok). The technology is uniquely designed so that a change in vaccine composition can be readily accommodated from one HA protein antigen to another one. Here we present a vaccine candidate to combat the recently emerged H7N9 virus as an example starting with the genetic sequence for the required HA, creation of the baculovirus and ending with purified protein antigen (or vaccine component) at the 10L scale accomplished within 38 days under GMP conditions. The same process performance is being achieved at the 2L, 10L, 100L, 650L and 2500L scale. An illustration is given of how the technology was transferred from the benchmark 650L scale facility to a retrofitted microbial facility at the 2500L scale within 100 days which includes the time for facility engineering changes. The successful development, technology transfer and scale-up of the Flublok process has major implications for being ready to make vaccine rapidly on a worldwide scale as a defense against pandemic influenza. The technology described does not have the same vulnerability to mutations in the egg adapted strain, and resulting loss in vaccine efficacy, faced by egg based manufacture.

  11. Electrotechnologies to process foods (United States)

    Electrical energy is being used to process foods. In conventional food processing plants, electricity drives mechanical devices and controls the degree of process. In recent years, several processing technologies are being developed to process foods directly with electricity. Electrotechnologies use...

  12. Studies on process synthesis and process integration


    Fien, Gert-Jan A. F.


    This thesis discusses topics in the field of process engineering that have received much attention over the past twenty years: (1) conceptual process synthesis using heuristic shortcut methods and (2) process integration through heat-exchanger networks and energy-saving power and refrigeration systems. The shortcut methods for conceptual process synthesis presented in Chapter 2, utilize Residue Curve Maps in ternary diagrams and are illustrated with examples of processes...

  13. Extensible packet processing architecture

    Energy Technology Data Exchange (ETDEWEB)

    Robertson, Perry J.; Hamlet, Jason R.; Pierson, Lyndon G.; Olsberg, Ronald R.; Chun, Guy D.


    A technique for distributed packet processing includes sequentially passing packets associated with packet flows between a plurality of processing engines along a flow through data bus linking the plurality of processing engines in series. At least one packet within a given packet flow is marked by a given processing engine to signify by the given processing engine to the other processing engines that the given processing engine has claimed the given packet flow for processing. A processing function is applied to each of the packet flows within the processing engines and the processed packets are output on a time-shared, arbitered data bus coupled to the plurality of processing engines.

  14. Process mineralogy IX

    Energy Technology Data Exchange (ETDEWEB)

    Petruk, W.; Hagni, R.D.; Pignolet-Brandom, S.; Hausen, D.M. (eds.) (Canada Centre for Mineral and Energy Technology, Ottawa, ON (Canada))


    54 papers are presented under the headings: keynote address; process mineralogy applications to mineral processing; process mineralogy applications to gold; process mineralogy applications to pyrometallurgy and hydrometallurgy; process mineralogy applications to environment and health; and process mineralogy applications to synthetic materials. Subject and author indexes are provided. Three papers have been abstracted separately.

  15. Thinning spatial point processes into Poisson processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Schoenberg, Frederic Paik


    are identified, and where we simulate backwards and forwards in order to obtain the thinned process. In the case of a Cox process, a simple independent thinning technique is proposed. In both cases, the thinning results in a Poisson process if and only if the true Papangelou conditional intensity is used, and...

  16. Thinning spatial point processes into Poisson processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Schoenberg, Frederic Paik

    , and where one simulates backwards and forwards in order to obtain the thinned process. In the case of a Cox process, a simple independent thinning technique is proposed. In both cases, the thinning results in a Poisson process if and only if the true Papangelou conditional intensity is used, and thus can...

  17. Refactoring Process Models in Large Process Repositories.

    NARCIS (Netherlands)

    Weber, B.; Reichert, M.U.


    With the increasing adoption of process-aware information systems (PAIS), large process model repositories have emerged. Over time respective models have to be re-aligned to the real-world business processes through customization or adaptation. This bears the risk that model redundancies are introdu

  18. Process Intensification: A Perspective on Process Synthesis

    DEFF Research Database (Denmark)

    Lutze, Philip; Gani, Rafiqul; Woodley, John


    In recent years, process intensification (PI) has attracted considerable academic interest as a potential means for process improvement, to meet the increasing demands for sustainable production. A variety of intensified operations developed in academia and industry creates a large number...... of options to potentially improve the process but to identify the set of feasible solutions for PI in which the optimal can be found takes considerable resources. Hence, a process synthesis tool to achieve PI would potentially assist in the generation and evaluation of PI options. Currently, several process...... of the main concepts is illustrated through an example involving the operation of a membrane reactor....

  19. The permanental process

    DEFF Research Database (Denmark)

    McCullagh, Peter; Møller, Jesper


    We extend the boson process first to a large class of Cox processes and second to an even larger class of infinitely divisible point processes. Density and moment results are studied in detail. These results are obtained in closed form as weighted permanents, so the extension i called a permanental...... process. Temporal extensions and a particularly tractable case of the permanental process are also studied. Extensions of the fermion process along similar lines, leading to so-called determinantal processes, are discussed....

  20. Food processing and allergenicity

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Vissers, Y.M.; Baumert, J.L.; Faludi, R.; Feys, M.; Flanagan, S.; Herouet-Guicheney, C.; Holzhauser, T.; Shimojo, R.; Bolt, N. van der; Wichers, H.; Kimber, I.


    Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed. In this review the impact of processing (heat and non-heat tre

  1. Food Processing and Allergenicity

    NARCIS (Netherlands)

    Verhoeckx, K.; Vissers, Y.; Baumert, J.L.; Faludi, R.; Fleys, M.; Flanagan, S.; Herouet-Guicheney, C.; Holzhauser, T.; Shimojo, R.; Bolt, van der Nieke; Wichers, H.J.; Kimber, I.


    Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed.

    In this review the impact of processing (heat and non

  2. SAR processing using SHARC signal processing systems (United States)

    Huxtable, Barton D.; Jackson, Christopher R.; Skaron, Steve A.


    Synthetic aperture radar (SAR) is uniquely suited to help solve the Search and Rescue problem since it can be utilized either day or night and through both dense fog or thick cloud cover. Other papers in this session, and in this session in 1997, describe the various SAR image processing algorithms that are being developed and evaluated within the Search and Rescue Program. All of these approaches to using SAR data require substantial amounts of digital signal processing: for the SAR image formation, and possibly for the subsequent image processing. In recognition of the demanding processing that will be required for an operational Search and Rescue Data Processing System (SARDPS), NASA/Goddard Space Flight Center and NASA/Stennis Space Center are conducting a technology demonstration utilizing SHARC multi-chip modules from Boeing to perform SAR image formation processing.


    Directory of Open Access Journals (Sweden)

    Suyono .


    Full Text Available The marginal distribution of integrated renewal process is derived in this paper. Our approach is based on the theory of point processes, especially Poisson point processes. The results are presented in the form of Laplace transforms.

  4. Integrated Process Capability Analysis

    Institute of Scientific and Technical Information of China (English)

    Chen; H; T; Huang; M; L; Hung; Y; H; Chen; K; S


    Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best spec...

  5. Product Development Process Modeling

    Institute of Scientific and Technical Information of China (English)


    The use of Concurrent Engineering and other modern methods of product development and maintenance require that a large number of time-overlapped "processes" be performed by many people. However, successfully describing and optimizing these processes are becoming even more difficult to achieve. The perspective of industrial process theory (the definition of process) and the perspective of process implementation (process transition, accumulation, and inter-operations between processes) are used to survey the method used to build one base model (multi-view) process model.

  6. From Process Understanding to Process Control

    NARCIS (Netherlands)

    Streefland, M.


    A licensed pharmaceutical process is required to be executed within the validated ranges throughout the lifetime of product manufacturing. Changes to the process usually require the manufacturer to demonstrate that the safety and efficacy of the product remains unchanged. Recent changes in the regul

  7. Business Process Redesign: Design the Improved Process (United States)


    64 C. MULTIVOTING ......... .................. .. 65 D. ELECTRONIC VOTING TECHNOLOGY ... ......... .. 65 v E. PAIRED...PROCESS IMPROVEMENT PROCESS (PIP) Diagram of each Activity (AI-A4) ......... .. 122 vi APPENDIX D: PRODUCTS AND VENDORS WHICH SUPPORT ELECTRONIC VOTING ............. 126...requirements. D. ELECTRONIC VOTING TECHNOLOGY Nunamaker [1992] suggests that traditional voting usual- ly happens at the end of a discussion, to close

  8. Idaho Chemical Processing Plant Process Efficiency improvements

    Energy Technology Data Exchange (ETDEWEB)

    Griebenow, B.


    In response to decreasing funding levels available to support activities at the Idaho Chemical Processing Plant (ICPP) and a desire to be cost competitive, the Department of Energy Idaho Operations Office (DOE-ID) and Lockheed Idaho Technologies Company have increased their emphasis on cost-saving measures. The ICPP Effectiveness Improvement Initiative involves many activities to improve cost effectiveness and competitiveness. This report documents the methodology and results of one of those cost cutting measures, the Process Efficiency Improvement Activity. The Process Efficiency Improvement Activity performed a systematic review of major work processes at the ICPP to increase productivity and to identify nonvalue-added requirements. A two-phase approach was selected for the activity to allow for near-term implementation of relatively easy process modifications in the first phase while obtaining long-term continuous improvement in the second phase and beyond. Phase I of the initiative included a concentrated review of processes that had a high potential for cost savings with the intent of realizing savings in Fiscal Year 1996 (FY-96.) Phase II consists of implementing long-term strategies too complex for Phase I implementation and evaluation of processes not targeted for Phase I review. The Phase II effort is targeted for realizing cost savings in FY-97 and beyond.

  9. Technology or Process First?

    DEFF Research Database (Denmark)

    Siurdyban, Artur Henryk; Svejvig, Per; Møller, Charles

    between them using strategic alignment, Enterprise Systems and Business Process Management theories. We argue that the insights from these cases can lead to a better alignment between process and technology. Implications for practice include the direction towards a closer integration of process...... and technology factors in organizations. Theoretical implications call for a design-oriented view of technology and process alignment....

  10. Thin film processes

    CERN Document Server

    Vossen, John L


    Remarkable advances have been made in recent years in the science and technology of thin film processes for deposition and etching. It is the purpose of this book to bring together tutorial reviews of selected filmdeposition and etching processes from a process viewpoint. Emphasis is placed on the practical use of the processes to provide working guidelines for their implementation, a guide to the literature, and an overview of each process.

  11. Metallurgical process engineering

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Ruiyu [Central Iron and Steel Research Institute (CISRI), Beijing (China)


    ''Metallurgical Process Engineering'' discusses large-scale integrated theory on the level of manufacturing production processes, putting forward concepts for exploring non-equilibrium and irreversible complex system. It emphasizes the dynamic and orderly operation of the steel plant manufacturing process, the major elements of which are the flow, process network and program. The book aims at establishing a quasi-continuous and continuous process system for improving several techno-economic indices, minimizing dissipation and enhancing the market competitiveness and sustainability of steel plants. The book is intended for engineers, researchers and managers in the fields of metallurgical engineering, industrial design, and process engineering. (orig.)

  12. Acoustic signal processing toolbox for array processing (United States)

    Pham, Tien; Whipps, Gene T.


    The US Army Research Laboratory (ARL) has developed an acoustic signal processing toolbox (ASPT) for acoustic sensor array processing. The intent of this document is to describe the toolbox and its uses. The ASPT is a GUI-based software that is developed and runs under MATLAB. The current version, ASPT 3.0, requires MATLAB 6.0 and above. ASPT contains a variety of narrowband (NB) and incoherent and coherent wideband (WB) direction-of-arrival (DOA) estimation and beamforming algorithms that have been researched and developed at ARL. Currently, ASPT contains 16 DOA and beamforming algorithms. It contains several different NB and WB versions of the MVDR, MUSIC and ESPRIT algorithms. In addition, there are a variety of pre-processing, simulation and analysis tools available in the toolbox. The user can perform simulation or real data analysis for all algorithms with user-defined signal model parameters and array geometries.

  13. News: Process intensification (United States)

    Conservation of materials and energy is a major objective to the philosophy of sustainability. Where production processes can be intensified to assist these objectives, significant advances have been developed to assist conservation as well as cost. Process intensification (PI) h...

  14. Group Decision Process Support

    DEFF Research Database (Denmark)

    Gøtze, John; Hijikata, Masao


    Introducing the notion of Group Decision Process Support Systems (GDPSS) to traditional decision-support theorists.......Introducing the notion of Group Decision Process Support Systems (GDPSS) to traditional decision-support theorists....

  15. Business Process Inventory (United States)

    Office of Personnel Management — Inventory of maps and descriptions of the business processes of the U.S. Office of Personnel Management (OPM), with an emphasis on the processes of the Office of the...

  16. Towards better process understanding

    DEFF Research Database (Denmark)

    Matero, Sanni Elina; van der Berg, Franciscus Winfried J; Poutiainen, Sami


    The manufacturing of tablets involves many unit operations that possess multivariate and complex characteristics. The interactions between the material characteristics and process related variation are presently not comprehensively analyzed due to univariate detection methods. As a consequence......, current best practice to control a typical process is to not allow process-related factors to vary i.e. lock the production parameters. The problem related to the lack of sufficient process understanding is still there: the variation within process and material properties is an intrinsic feature...... and cannot be compensated for with constant process parameters. Instead, a more comprehensive approach based on the use of multivariate tools for investigating processes should be applied. In the pharmaceutical field these methods are referred to as Process Analytical Technology (PAT) tools that aim...

  17. Secure Processing Lab (United States)

    Federal Laboratory Consortium — The Secure Processing Lab is the center of excellence for new and novel processing techniques for the formation, calibration and analysis of radar. In addition, this...

  18. Radiochemical Processing Laboratory (RPL) (United States)

    Federal Laboratory Consortium — The Radiochemical Processing Laboratory (RPL)�is a scientific facility funded by DOE to create and implement innovative processes for environmental clean-up and...

  19. Infrared processing of foods (United States)

    Infrared (IR) processing of foods has been gaining popularity over conventional processing in several unit operations, including drying, peeling, baking, roasting, blanching, pasteurization, sterilization, disinfection, disinfestation, cooking, and popping . It has shown advantages over conventional...

  20. Dairy processing, Improving quality

    NARCIS (Netherlands)

    Smit, G.


    This book discusses raw milk composition, production and quality, and reviews developments in processing from hygiene and HACCP systems to automation, high-pressure processing and modified atmosphere packaging.

  1. Stochastic processes - quantum physics

    Energy Technology Data Exchange (ETDEWEB)

    Streit, L. (Bielefeld Univ. (Germany, F.R.))


    The author presents an elementary introduction to stochastic processes. He starts from simple quantum mechanics and considers problems in probability, finally presenting quantum dynamics in terms of stochastic processes.

  2. Drug Development Process (United States)

    ... Device Approvals The Drug Development Process The Drug Development Process Share Tweet Linkedin Pin it More sharing ... Pin it Email Print Step 1 Discovery and Development Discovery and Development Research for a new drug ...

  3. Polyamines in tea processing. (United States)

    Palavan-Unsal, Narcin; Arisan, Elif Damla; Terzioglu, Salih


    The distribution of dietary polyamines, putrescine, spermidine and spermine, was determined during processing of Camellia sinensis. Black tea manufacture is carried by a series of processes on fresh tea leaves involving withering, rolling, fermentation, drying and sieving. The aim of this research was to determine the effect of tea processing on the polyamine content in relation with antioxidant enzymes, superoxide dismutase, lipid peroxidase and glutathione peroxidase. Before processing, the spermine content was much higher than the putrescine and spermidine content in green tea leaves. Spermine was significantly decreased during processing while the putrescine and spermine contents increased during withered and rolling and decreased in the following stages. The superoxide dismutase activity increased at the withering stage and declined during processing. The transcript level of the polyamine biosynthesis-responsible enzyme ornithine decarboxylase was reduced during each processing step. This study reveals the importance of protection of nutritional compounds that are essential for health during the manufacturing process.

  4. Grind hardening process

    CERN Document Server

    Salonitis, Konstantinos


    This book presents the grind-hardening process and the main studies published since it was introduced in 1990s.  The modelling of the various aspects of the process, such as the process forces, temperature profile developed, hardness profiles, residual stresses etc. are described in detail. The book is of interest to the research community working with mathematical modeling and optimization of manufacturing processes.

  5. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne


    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  6. Software Process Improvement Defined

    DEFF Research Database (Denmark)

    Aaen, Ivan


    This paper argues in favor of the development of explanatory theory on software process improvement. The last one or two decades commitment to prescriptive approaches in software process improvement theory may contribute to the emergence of a gulf dividing theorists and practitioners....... It is proposed that this divide be met by the development of theory evaluating prescriptive approaches and informing practice with a focus on the software process policymaking and process control aspects of improvement efforts...

  7. Auditory processing models

    DEFF Research Database (Denmark)

    Dau, Torsten


    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook will pr...

  8. Semisolid Metal Processing Consortium

    Energy Technology Data Exchange (ETDEWEB)



    Mathematical modeling and simulations of semisolid filling processes remains a critical issue in understanding and optimizing the process. Semisolid slurries are non-Newtonian materials that exhibit complex rheological behavior. There the way these slurries flow in cavities is very different from the way liquid in classical casting fills cavities. Actually filling in semisolid processing is often counter intuitive

  9. Clinical Process Intelligence

    DEFF Research Database (Denmark)

    Vilstrup Pedersen, Klaus


    .e. local guidelines. From a knowledge management point of view, this externalization of generalized processes, gives the opportunity to learn from, evaluate and optimize the processes. "Clinical Process Intelligence" (CPI), will denote the goal of getting generalized insight into patient centered health...

  10. Biomass process handbook

    Energy Technology Data Exchange (ETDEWEB)


    Descriptions are given of 42 processes which use biomass to produce chemical products. Marketing and economic background, process description, flow sheets, costs, major equipment, and availability of technology are given for each of the 42 processes. Some of the chemicals discussed are: ethanol, ethylene, acetaldehyde, butanol, butadiene, acetone, citric acid, gluconates, itaconic acid, lactic acid, xanthan gum, sorbitol, starch polymers, fatty acids, fatty alcohols, glycerol, soap, azelaic acid, perlargonic acid, nylon-11, jojoba oil, furfural, furfural alcohol, tetrahydrofuran, cellulose polymers, products from pulping wastes, and methane. Processes include acid hydrolysis, enzymatic hydrolysis, fermentation, distillation, Purox process, and anaerobic digestion.

  11. Thin film processes II

    CERN Document Server

    Kern, Werner


    This sequel to the 1978 classic, Thin Film Processes, gives a clear, practical exposition of important thin film deposition and etching processes that have not yet been adequately reviewed. It discusses selected processes in tutorial overviews with implementation guide lines and an introduction to the literature. Though edited to stand alone, when taken together, Thin Film Processes II and its predecessor present a thorough grounding in modern thin film techniques.Key Features* Provides an all-new sequel to the 1978 classic, Thin Film Processes* Introduces new topics, and sever

  12. Colloid process engineering

    CERN Document Server

    Peukert, Wolfgang; Rehage, Heinz; Schuchmann, Heike


    This book deals with colloidal systems in technical processes and the influence of colloidal systems by technical processes. It explores how new measurement capabilities can offer the potential for a dynamic development of scientific and engineering, and examines the origin of colloidal systems and its use for new products. The future challenges to colloidal process engineering are the development of appropriate equipment and processes for the production and obtainment of multi-phase structures and energetic interactions in market-relevant quantities. The book explores the relevant processes and for controlled production and how they can be used across all scales.

  13. Silicon production process evaluations (United States)


    Chemical engineering analyses involving the preliminary process design of a plant (1,000 metric tons/year capacity) to produce silicon via the technology under consideration were accomplished. Major activities in the chemical engineering analyses included base case conditions, reaction chemistry, process flowsheet, material balance, energy balance, property data, equipment design, major equipment list, production labor and forward for economic analysis. The process design package provided detailed data for raw materials, utilities, major process equipment and production labor requirements necessary for polysilicon production in each process.

  14. Data processing made simple

    CERN Document Server

    Wooldridge, Susan


    Data Processing: Made Simple, Second Edition presents discussions of a number of trends and developments in the world of commercial data processing. The book covers the rapid growth of micro- and mini-computers for both home and office use; word processing and the 'automated office'; the advent of distributed data processing; and the continued growth of database-oriented systems. The text also discusses modern digital computers; fundamental computer concepts; information and data processing requirements of commercial organizations; and the historical perspective of the computer industry. The

  15. Dynamical laser spike processing

    CERN Document Server

    Shastri, Bhavin J; Tait, Alexander N; Rodriguez, Alejandro W; Wu, Ben; Prucnal, Paul R


    Novel materials and devices in photonics have the potential to revolutionize optical information processing, beyond conventional binary-logic approaches. Laser systems offer a rich repertoire of useful dynamical behaviors, including the excitable dynamics also found in the time-resolved "spiking" of neurons. Spiking reconciles the expressiveness and efficiency of analog processing with the robustness and scalability of digital processing. We demonstrate that graphene-coupled laser systems offer a unified low-level spike optical processing paradigm that goes well beyond previously studied laser dynamics. We show that this platform can simultaneously exhibit logic-level restoration, cascadability and input-output isolation---fundamental challenges in optical information processing. We also implement low-level spike-processing tasks that are critical for higher level processing: temporal pattern detection and stable recurrent memory. We study these properties in the context of a fiber laser system, but the addit...

  16. A secondary fuel removal process: plasma processing

    Energy Technology Data Exchange (ETDEWEB)

    Min, J. Y.; Kim, Y. S. [Hanyang Univ., Seoul (Korea, Republic of); Bae, K. K.; Yang, M. S. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)


    Plasma etching process of UO{sub 2} by using fluorine containing gas plasma is studied as a secondary fuel removal process for DUPIC (Direct Use of PWR spent fuel Into Candu) process which is taken into consideration for potential future fuel cycle in Korea. CF{sub 4}/O{sub 2} gas mixture is chosen for reactant gas and the etching rates of UO{sub 2} by the gas plasma are investigated as functions of CF{sub 4}/O{sub 2} ratio, plasma power, substrate temperature, and plasma gas pressure. It is found that the optimum CF{sub 4}/O{sub 2} ratio is around 4:1 at all temperatures up to 400 deg C and the etching rate increases with increasing r.f. power and substrate temperature. Under 150W r.f. power the etching rate reaches 1100 monolayers/min at 400 deg C, which is equivalent to about 0.5mm/min. (author).

  17. Business Model Process Configurations

    DEFF Research Database (Denmark)

    Taran, Yariv; Nielsen, Christian; Thomsen, Peter


    Purpose – The paper aims: 1) To develop systematically a structural list of various business model process configuration and to group (deductively) these selected configurations in a structured typological categorization list. 2) To facilitate companies in the process of BM innovation, by develop......Purpose – The paper aims: 1) To develop systematically a structural list of various business model process configuration and to group (deductively) these selected configurations in a structured typological categorization list. 2) To facilitate companies in the process of BM innovation......, by developing (inductively) an ontological classification framework, in view of the BM process configurations typology developed. Design/methodology/approach – Given the inconsistencies found in the business model studies (e.g. definitions, configurations, classifications) we adopted the analytical induction...... method of data analysis. Findings - A comprehensive literature review and analysis resulted in a list of business model process configurations systematically organized under five classification groups, namely, revenue model; value proposition; value configuration; target customers, and strategic...

  18. Decomposability for stable processes

    CERN Document Server

    Wang, Yizao; Roy, Parthanil


    We characterize all possible independent symmetric $\\alpha$-stable (S$\\alpha$S) components of a non--Gaussian S$\\alpha$S process, $0<\\alpha<2$. In particular, we characterize the independent stationary S$\\alpha$S components of a stationary S$\\alpha$S process. One simple consequence of our characterization is that all stationary components of the S$\\alpha$S moving average processes are trivial. As a main application, we show that the standard Brown--Resnick process has a moving average representation. This complements a result of Kabluchko et al. (2009), who obtained mixed moving average representations for these processes. We also develop a parallel characterization theory for max-stable processes.

  19. Badge Office Process Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Haurykiewicz, John Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dinehart, Timothy Grant [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Parker, Robert Young [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    The purpose of this process analysis was to analyze the Badge Offices’ current processes from a systems perspective and consider ways of pursuing objectives set forth by SEC-PS, namely increased customer flow (throughput) and reduced customer wait times. Information for the analysis was gathered for the project primarily through Badge Office Subject Matter Experts (SMEs), and in-person observation of prevailing processes. Using the information gathered, a process simulation model was constructed to represent current operations and allow assessment of potential process changes relative to factors mentioned previously. The overall purpose of the analysis was to provide SEC-PS management with information and recommendations to serve as a basis for additional focused study and areas for potential process improvements in the future.

  20. Linearity in Process Languages

    DEFF Research Database (Denmark)

    Nygaard, Mikkel; Winskel, Glynn


    The meaning and mathematical consequences of linearity (managing without a presumed ability to copy) are studied for a path-based model of processes which is also a model of affine-linear logic. This connection yields an affine-linear language for processes, automatically respecting open-map bisi......The meaning and mathematical consequences of linearity (managing without a presumed ability to copy) are studied for a path-based model of processes which is also a model of affine-linear logic. This connection yields an affine-linear language for processes, automatically respecting open......-map bisimulation, in which a range of process operations can be expressed. An operational semantics is provided for the tensor fragment of the language. Different ways to make assemblies of processes lead to different choices of exponential, some of which respect bisimulation....

  1. Process Improvement Essentials

    CERN Document Server

    Persse, James R


    Process Improvement Essentials combines the foundation needed to understand process improvement theory with the best practices to help individuals implement process improvement initiatives in their organization. The three leading programs: ISO 9001:2000, CMMI, and Six Sigma--amidst the buzz and hype--tend to get lumped together under a common label. This book delivers a combined guide to all three programs, compares their applicability, and then sets the foundation for further exploration.

  2. TEP process flow diagram

    Energy Technology Data Exchange (ETDEWEB)

    Wilms, R Scott [Los Alamos National Laboratory; Carlson, Bryan [Los Alamos National Laboratory; Coons, James [Los Alamos National Laboratory; Kubic, William [Los Alamos National Laboratory


    This presentation describes the development of the proposed Process Flow Diagram (PFD) for the Tokamak Exhaust Processing System (TEP) of ITER. A brief review of design efforts leading up to the PFD is followed by a description of the hydrogen-like, air-like, and waterlike processes. Two new design values are described; the mostcommon and most-demanding design values. The proposed PFD is shown to meet specifications under the most-common and mostdemanding design values.

  3. Business process transformation

    CERN Document Server

    Grover, Varun


    Featuring contributions from prominent thinkers and researchers, this volume in the ""Advances in Management Information Systems"" series provides a rich set of conceptual, empirical, and introspective studies that epitomize fundamental knowledge in the area of Business Process Transformation. Processes are interpreted broadly to include operational and managerial processes within and between organizations, as well as those involved in knowledge generation. Transformation includes radical and incremental change, its conduct, management, and outcome. The editors and contributing authors pay clo

  4. Jointly Poisson processes

    CERN Document Server

    Johnson, D H


    What constitutes jointly Poisson processes remains an unresolved issue. This report reviews the current state of the theory and indicates how the accepted but unproven model equals that resulting from the small time-interval limit of jointly Bernoulli processes. One intriguing consequence of these models is that jointly Poisson processes can only be positively correlated as measured by the correlation coefficient defined by cumulants of the probability generating functional.

  5. Multiphoton processes: conference proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Lambropoulos, P.; Smith, S.J. (eds.)


    The chapters of this volume represent the invited papers delivered at the conference. They are arranged according to thermatic proximity beginning with atoms and continuing with molecules and surfaces. Section headings include multiphoton processes in atoms, field fluctuations and collisions in multiphoton process, and multiphoton processes in molecules and surfaces. Abstracts of individual items from the conference were prepared separately for the data base. (GHT)

  6. Polygon mesh processing

    CERN Document Server

    Botsch, Mario; Pauly, Mark; Alliez, Pierre; Levy, Bruno


    Geometry processing, or mesh processing, is a fast-growing area of research that uses concepts from applied mathematics, computer science, and engineering to design efficient algorithms for the acquisition, reconstruction, analysis, manipulation, simulation, and transmission of complex 3D models. Applications of geometry processing algorithms already cover a wide range of areas from multimedia, entertainment, and classical computer-aided design, to biomedical computing, reverse engineering, and scientific computing. Over the last several years, triangle meshes have become increasingly popular,

  7. Basic digital signal processing

    CERN Document Server

    Lockhart, Gordon B


    Basic Digital Signal Processing describes the principles of digital signal processing and experiments with BASIC programs involving the fast Fourier theorem (FFT). The book reviews the fundamentals of the BASIC program, continuous and discrete time signals including analog signals, Fourier analysis, discrete Fourier transform, signal energy, power. The text also explains digital signal processing involving digital filters, linear time-variant systems, discrete time unit impulse, discrete-time convolution, and the alternative structure for second order infinite impulse response (IIR) sections.

  8. NASA Hazard Analysis Process (United States)

    Deckert, George


    This viewgraph presentation reviews The NASA Hazard Analysis process. The contents include: 1) Significant Incidents and Close Calls in Human Spaceflight; 2) Subsystem Safety Engineering Through the Project Life Cycle; 3) The Risk Informed Design Process; 4) Types of NASA Hazard Analysis; 5) Preliminary Hazard Analysis (PHA); 6) Hazard Analysis Process; 7) Identify Hazardous Conditions; 8) Consider All Interfaces; 9) Work a Preliminary Hazard List; 10) NASA Generic Hazards List; and 11) Final Thoughts

  9. Scientific information processing procedures

    Directory of Open Access Journals (Sweden)

    García, Maylin


    Full Text Available The paper systematizes several theoretical view-points on scientific information processing skill. It decomposes the processing skills into sub-skills. Several methods such analysis, synthesis, induction, deduction, document analysis were used to build up a theoretical framework. Interviews and survey to professional being trained and a case study was carried out to evaluate the results. All professional in the sample improved their performance in scientific information processing.

  10. Multimodal Processes Rescheduling

    DEFF Research Database (Denmark)

    Bocewicz, Grzegorz; Banaszak, Zbigniew A.; Nielsen, Peter


    Cyclic scheduling problems concerning multimodal processes are usually observed in FMSs producing multi-type parts where the Automated Guided Vehicles System (AGVS) plays a role of a material handling system. Schedulability analysis of concurrently flowing cyclic processes (SCCP) exe-cuted in the......Cyclic scheduling problems concerning multimodal processes are usually observed in FMSs producing multi-type parts where the Automated Guided Vehicles System (AGVS) plays a role of a material handling system. Schedulability analysis of concurrently flowing cyclic processes (SCCP) exe...

  11. Fuels Processing Laboratory (United States)

    Federal Laboratory Consortium — NETL’s Fuels Processing Laboratory in Morgantown, WV, provides researchers with the equipment they need to thoroughly explore the catalytic issues associated with...

  12. Process modeling style

    CERN Document Server

    Long, John


    Process Modeling Style focuses on other aspects of process modeling beyond notation that are very important to practitioners. Many people who model processes focus on the specific notation used to create their drawings. While that is important, there are many other aspects to modeling, such as naming, creating identifiers, descriptions, interfaces, patterns, and creating useful process documentation. Experience author John Long focuses on those non-notational aspects of modeling, which practitioners will find invaluable. Gives solid advice for creating roles, work produ

  13. Living olefin polymerization processes (United States)

    Schrock, Richard R.; Baumann, Robert


    Processes for the living polymerization of olefin monomers with terminal carbon-carbon double bonds are disclosed. The processes employ initiators that include a metal atom and a ligand having two group 15 atoms and a group 16 atom or three group 15 atoms. The ligand is bonded to the metal atom through two anionic or covalent bonds and a dative bond. The initiators are particularly stable under reaction conditions in the absence of olefin monomer. The processes provide polymers having low polydispersities, especially block copolymers having low polydispersities. It is an additional advantage of these processes that, during block copolymer synthesis, a relatively small amount of homopolymer is formed.

  14. Financial information processing

    Institute of Scientific and Technical Information of China (English)

    Shuo BAI; Shouyang WANG; Lean YU; Aoying ZHOU


    @@ The rapid growth in financial data volume has made financial information processing more and more difficult due to the increase in complexity, which has forced businesses and academics alike to turn to sophisticated information processing technologies for better solutions. A typical feature is that high-performance computers and advanced computational techniques play ever-increasingly important roles for business and industries to have competitive advantages. Accordingly, financial information processing has emerged as a new cross-disciplinary field integrating computer science, mathematics, financial economics, intelligent techniques, and computer simulations to make different decisions based on processed financial information.

  15. The Recruitment Process:

    DEFF Research Database (Denmark)

    Holm, Anna

    The aim of this research was to determine whether the introduction of e-recruitment has an impact on the process and underlying tasks, subtasks and activities of recruitment. Three large organizations with well-established e-recruitment practices were included in the study. The three case studies......, which were carried out in Denmark in 2008-2009 using qualitative research methods, revealed changes in the sequence, divisibility and repetitiveness of a number of recruitment tasks and subtasks. The new recruitment process design was identified and presented in the paper. The study concluded...... that the main task of the process shifted from processing applications to communicating with candidates....

  16. Biased predecision processing. (United States)

    Brownstein, Aaron L


    Decision makers conduct biased predecision processing when they restructure their mental representation of the decision environment to favor one alternative before making their choice. The question of whether biased predecision processing occurs has been controversial since L. Festinger (1957) maintained that it does not occur. The author reviews relevant research in sections on theories of cognitive dissonance, decision conflict, choice certainty, action control, action phases, dominance structuring, differentiation and consolidation, constructive processing, motivated reasoning, and groupthink. Some studies did not find evidence of biased predecision processing, but many did. In the Discussion section, the moderators are summarized and used to assess the theories.

  17. Acoustic Signal Processing (United States)

    Hartmann, William M.; Candy, James V.

    Signal processing refers to the acquisition, storage, display, and generation of signals - also to the extraction of information from signals and the re-encoding of information. As such, signal processing in some form is an essential element in the practice of all aspects of acoustics. Signal processing algorithms enable acousticians to separate signals from noise, to perform automatic speech recognition, or to compress information for more efficient storage or transmission. Signal processing concepts are the building blocks used to construct models of speech and hearing. Now, in the 21st century, all signal processing is effectively digital signal processing. Widespread access to high-speed processing, massive memory, and inexpensive software make signal processing procedures of enormous sophistication and power available to anyone who wants to use them. Because advanced signal processing is now accessible to everybody, there is a need for primers that introduce basic mathematical concepts that underlie the digital algorithms. The present handbook chapter is intended to serve such a purpose.

  18. Cooperative internal conversion process

    CERN Document Server

    Kálmán, Péter


    A new phenomenon, called cooperative internal conversion process, in which the coupling of bound-free electron and neutron transitions due to the dipole term of their Coulomb interaction permits cooperation of two nuclei leading to neutron exchange if it is allowed by energy conservation, is discussed theoretically. General expression of the cross section of the process is reported in one particle nuclear and spherical shell models as well in the case of free atoms (e.g. noble gases). A half-life characteristic of the process is also determined. The case of $Ne$ is investigated numerically. The process may have significance in fields of nuclear waste disposal and nuclear energy production.

  19. Kuhlthau's Information Search Process. (United States)

    Shannon, Donna


    Explains Kuhlthau's Information Search Process (ISP) model which is based on a constructivist view of learning and provides a framework for school library media specialists for the design of information services and instruction. Highlights include a shift from library skills to information skills; attitudes; process approach; and an interview with…

  20. The Analytical Hierarchy Process

    DEFF Research Database (Denmark)

    Barfod, Michael Bruhn


    The technical note gathers the theory behind the Analytical Hierarchy Process (AHP) and present its advantages and disadvantages in practical use.......The technical note gathers the theory behind the Analytical Hierarchy Process (AHP) and present its advantages and disadvantages in practical use....

  1. Mineral Processing Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)



    This document represents the roadmap for Processing Technology Research in the US Mining Industry. It was developed based on the results of a Processing Technology Roadmap Workshop sponsored by the National Mining Association in conjunction with the US Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Industrial Technologies. The Workshop was held January 24 - 25, 2000.

  2. Technologies for Optical Processing

    DEFF Research Database (Denmark)

    Stubkjær, Kristian


    The article consists of a Powerpoint presentation on technologies for optical processing. The paper concludes that the nonlinear elements based on SOA, fibers and waveguide structures have capabilities of simple processing at data rates of 100-600 Gb/s. Switching powers comparable to electronics...

  3. Cognitive Processes and Achievement. (United States)

    Hunt, Dennis; Randhawa, Bikkar S.

    For a group of 165 fourth- and fifth-grade students, four achievement test scores were correlated with success on nine tests designed to measure three cognitive functions: sustained attention, successive processing, and simultaneous processing. This experiment was designed in accordance with Luria's model of the three functional units of the…

  4. The process of entrepreneurship:

    DEFF Research Database (Denmark)

    Neergaard, Helle


    Growing a technology-based new venture is a complex process because these ventures are embedded in turbulent environments that require fast organisational and managerial transformation. This chapter addresses the evolutionary process of such ventures. It seeks to provide insight into the link...

  5. Process Writing Checklist. (United States)

    Jenks, Christopher J.

    This checklist is designed to help develop writing strategies for English language learners (ELLs), focusing on a variety of linguistic strategies inherent in the writing process. It provides them with a graphical representation of the cognitive process involved in complex writing, promoting self-assessment strategies and integrating oral…

  6. Food processing and allergenicity. (United States)

    Verhoeckx, Kitty C M; Vissers, Yvonne M; Baumert, Joseph L; Faludi, Roland; Feys, Marcel; Flanagan, Simon; Herouet-Guicheney, Corinne; Holzhauser, Thomas; Shimojo, Ryo; van der Bolt, Nieke; Wichers, Harry; Kimber, Ian


    Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed. In this review the impact of processing (heat and non-heat treatment) on the allergenic potential of proteins, and on the antigenic (IgG-binding) and allergenic (IgE-binding) properties of proteins has been considered. A variety of allergenic foods (peanuts, tree nuts, cows' milk, hens' eggs, soy, wheat and mustard) have been reviewed. The overall conclusion drawn is that processing does not completely abolish the allergenic potential of allergens. Currently, only fermentation and hydrolysis may have potential to reduce allergenicity to such an extent that symptoms will not be elicited, while other methods might be promising but need more data. Literature on the effect of processing on allergenic potential and the ability to induce sensitisation is scarce. This is an important issue since processing may impact on the ability of proteins to cause the acquisition of allergic sensitisation, and the subject should be a focus of future research. Also, there remains a need to develop robust and integrated methods for the risk assessment of food allergenicity.

  7. Process innovation laboratory

    DEFF Research Database (Denmark)

    Møller, Charles


    Most organizations today are required not only to operate effective business processes but also to allow for changing business conditions at an increasing rate. Today nearly every business relies on their enterprise information systems (EIS) for process integration and future generations of EIS...

  8. Hyperspectral image processing methods (United States)

    Hyperspectral image processing refers to the use of computer algorithms to extract, store and manipulate both spatial and spectral information contained in hyperspectral images across the visible and near-infrared portion of the electromagnetic spectrum. A typical hyperspectral image processing work...

  9. Flow generating processes

    NARCIS (Netherlands)

    Lanen, van H.A.J.; Fendeková, M.; Kupczyk, E.; Kasprzyk, A.; Pokojski, W.


    This chapter starts with an overview of how climatic water deficits affect hydrological processes in different type of catchments. It then continues with a more comprehensive description of drought relevant processes. Two catchments in climatologically contrasting regions are used for illustrative p

  10. WWTP Process Tank Modelling

    DEFF Research Database (Denmark)

    Laursen, Jesper

    hydrofoil shaped propellers. These two sub-processes deliver the main part of the supplied energy to the activated sludge tank, and for this reason they are important for the mixing conditions in the tank. For other important processes occurring in the activated sludge tank, existing models and measurements...

  11. Uranium processing and properties

    CERN Document Server


    Covers a broad spectrum of topics and applications that deal with uranium processing and the properties of uranium Offers extensive coverage of both new and established practices for dealing with uranium supplies in nuclear engineering Promotes the documentation of the state-of-the-art processing techniques utilized for uranium and other specialty metals

  12. Relational Processing Following Stroke (United States)

    Andrews, Glenda; Halford, Graeme S.; Shum, David; Maujean, Annick; Chappell, Mark; Birney, Damian


    The research examined relational processing following stroke. Stroke patients (14 with frontal, 30 with non-frontal lesions) and 41 matched controls completed four relational processing tasks: sentence comprehension, Latin square matrix completion, modified Dimensional Change Card Sorting, and n-back. Each task included items at two or three…

  13. Monitoring Business Processes (United States)

    Bellandi, Valerio; Ceravolo, Paolo; Damiani, Ernesto; Frati, Fulvio

    In this chapter, we introduce the TEKNE Metrics Framework that performs services to monitor business processes. This framework was designed to support the prescription and explanation of these processes. TEKNE's most innovative contribution is managing data expressed in declarative form. To face this challenge, the TEKNE project implemented an infrastructure that relies on declarative Semantic Web technologies designed to be used in distributed systems.

  14. Image processing mini manual (United States)

    Matthews, Christine G.; Posenau, Mary-Anne; Leonard, Desiree M.; Avis, Elizabeth L.; Debure, Kelly R.; Stacy, Kathryn; Vonofenheim, Bill


    The intent is to provide an introduction to the image processing capabilities available at the Langley Research Center (LaRC) Central Scientific Computing Complex (CSCC). Various image processing software components are described. Information is given concerning the use of these components in the Data Visualization and Animation Laboratory at LaRC.

  15. Hybrid quantum information processing

    Energy Technology Data Exchange (ETDEWEB)

    Furusawa, Akira [Department of Applied Physics, School of Engineering, The University of Tokyo (Japan)


    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  16. Organic food processing

    DEFF Research Database (Denmark)

    Kahl, Johannes; Alborzi, Farnaz; Beck, Alexander


    In 2007 EU Regulation (EC) 834/2007 introduced principles and criteria for organic food processing. These regulations have been analysed and discussed in several scientific publications and research project reports. Recently, organic food quality was described by principles, aspects and criteria....... These principles from organic agriculture were verified and adapted for organic food processing. Different levels for evaluation were suggested. In another document, underlying paradigms and consumer perception of organic food were reviewed against functional food, resulting in identifying integral product...... to evaluate processing methods. Therefore the goal of this paper is to describe and discuss the topic of organic food processing to make it operational. A conceptual background for organic food processing is given by verifying the underlying paradigms and principles of organic farming and organic food as well...

  17. Beryllium chemistry and processing

    CERN Document Server

    Walsh, Kenneth A


    This book introduces beryllium; its history, its chemical, mechanical, and physical properties including nuclear properties. The 29 chapters include the mineralogy of beryllium and the preferred global sources of ore bodies. The identification and specifics of the industrial metallurgical processes used to form oxide from the ore and then metal from the oxide are thoroughly described. The special features of beryllium chemistry are introduced, including analytical chemical practices. Beryllium compounds of industrial interest are identified and discussed. Alloying, casting, powder processing, forming, metal removal, joining and other manufacturing processes are covered. The effect of composition and process on the mechanical and physical properties of beryllium alloys assists the reader in material selection. The physical metallurgy chapter brings conformity between chemical and physical metallurgical processing of beryllium, metal, alloys, and compounds. The environmental degradation of beryllium and its all...

  18. Posttranslational processing of progastrin

    DEFF Research Database (Denmark)

    Bundgaard, Jens René; Rehfeld, Jens F.


    Gastrin and cholecystokinin (CCK) are homologous hormones with important functions in the brain and the gut. Gastrin is the main regulator of gastric acid secretion and gastric mucosal growth, whereas cholecystokinin regulates gall bladder emptying, pancreatic enzyme secretion and besides acts...... processing progastrin is often greatly disturbed in neoplastic cells.The posttranslational phase of the biogenesis of gastrin and the various progastrin products in gastrin gene-expressing tissues is now reviewed here. In addition, the individual contributions of the processing enzymes are discussed......, as are structural features of progastrin that are involved in the precursor activation process. Thus, the review describes how the processing depends on the cell-specific expression of the processing enzymes and kinetics in the secretory pathway....

  19. Managing Software Process Evolution

    DEFF Research Database (Denmark)

    This book focuses on the design, development, management, governance and application of evolving software processes that are aligned with changing business objectives, such as expansion to new domains or shifting to global production. In the context of an evolving business world, it examines...... the complete software process lifecycle, from the initial definition of a product to its systematic improvement. In doing so, it addresses difficult problems, such as how to implement processes in highly regulated domains or where to find a suitable notation system for documenting processes, and provides...... essential insights and tips to help readers manage process evolutions. And last but not least, it provides a wealth of examples and cases on how to deal with software evolution in practice. Reflecting these topics, the book is divided into three parts. Part 1 focuses on software business transformation...

  20. Business Process Management (United States)

    Mendling, Jan

    The recent progress of Business Process Management (BPM) is reflected by the figures of the related industry. Wintergreen Research estimates that the international market for BPM-related software and services accounted for more than USD 1 billion in 2005 with a tendency towards rapid growth in the subsequent couple of years [457]. The relevance of business process modeling to general management initiatives has been previously studied in the 1990s [28]. Today, Gartner finds that organizations that had the best results in implementing business process management spent more than 40 percent of the total project time on discovery and construction of their initial process model [265]. As a consequence, Gartner considers Business Process Modeling to be among the Top 10 Strategic Technologies for 2008.

  1. New Processes for Annulation

    Institute of Scientific and Technical Information of China (English)

    Liu Hsing-Jang


    Making use of the high propensity of 2-cyano-2-cycloalkenones to undergo conjugate addition with various carbanions and the high reactivity of the ensuing α -cyano ketone system, a number of new annulation processes have been developed recently in our laboratories. As shown in Eq. 1 (n=1) with a specific example, one such process involves the addition of 3-butenylmagnesium bromide, followed by a palladium (Ⅱ) acetate mediated oxidative cyclization, to facilitate methylenecyclopentane ring formation. This annulation process could be readily extended to effect methylenecyclohexane ring formation (Eq. 1, n=2), using 4-pentenylmagnesinm bromide as the initial reagent, and to install the carbomethoxy-substituted methylenecyclopentane and methylenecyclohexane rings, using the carbanions derived from methyl 4-pentenoate and methyl 5-hexenoate, respectively (Eq. 2). In another annulation process, the addition of the enolate of methyl 5-chloropentanoate is involved initially, and the ring formation is readily effected by an intramolecular alkylation process. A specific example is given in Eq. 3.

  2. Business process support

    Energy Technology Data Exchange (ETDEWEB)

    Carle, Adriana; Fiducia, Daniel [Transportadora de Gas del Sur S.A. (TGS), Buenos Aires (Argentina)


    This paper is about the own development of business support software. The developed applications are used to support two business processes: one of them is the process of gas transportation and the other is the natural gas processing. This software has interphases with the ERP SAP, software SCADA and on line gas transportation simulation software. The main functionalities of the applications are: entrance on line real time of clients transport nominations, transport programming, allocation of the clients transport nominations, transport control, measurements, balanced pipeline, allocation of gas volume to the gas processing plants, calculate of product tons processed in each plant and tons of product distributed to clients. All the developed software generates information to the internal staff, regulatory authorities and clients. (author)

  3. Nonhomogeneous fractional Poisson processes

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaotian [School of Management, Tianjin University, Tianjin 300072 (China)]. E-mail:; Zhang Shiying [School of Management, Tianjin University, Tianjin 300072 (China); Fan Shen [Computer and Information School, Zhejiang Wanli University, Ningbo 315100 (China)


    In this paper, we propose a class of non-Gaussian stationary increment processes, named nonhomogeneous fractional Poisson processes W{sub H}{sup (j)}(t), which permit the study of the effects of long-range dependance in a large number of fields including quantum physics and finance. The processes W{sub H}{sup (j)}(t) are self-similar in a wide sense, exhibit more fatter tail than Gaussian processes, and converge to the Gaussian processes in distribution in some cases. In addition, we also show that the intensity function {lambda}(t) strongly influences the existence of the highest finite moment of W{sub H}{sup (j)}(t) and the behaviour of the tail probability of W{sub H}{sup (j)}(t)

  4. Conceptualizing operations strategy processes

    DEFF Research Database (Denmark)

    Rytter, Niels Gorm; Boer, Harry; Koch, Christian


    Purpose - The purpose of this paper is to present insights into operations strategy (OS) in practice. It outlines a conceptualization and model of OS processes and, based on findings from an in-depth and longitudinal case study, contributes to further development of extant OS models and methods......; taking place in five dimensions of change - technical-rational, cultural, political, project management, and facilitation; and typically unfolding as a sequential and parallel, ordered and disordered, planned and emergent as well as top-down and bottom-up process. The proposed OS conceptualization...... outcomes for an OS process in practice, change agents may need to moderate their outcome ambitions, manage process dimensions and agendas in a situational manner, balance inherent process paradoxes, strive at bridging both language and reality, as well as mobilizing key stakeholders, especially middle...

  5. Branching processes in biology

    CERN Document Server

    Kimmel, Marek


    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  6. Formed HIP Can Processing

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, Kester Diederik [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    The intent of this report is to document a procedure used at LANL for HIP bonding aluminum cladding to U-10Mo fuel foils using a formed HIP can for the Domestic Reactor Conversion program in the NNSA Office of Material, Management and Minimization, and provide some details that may not have been published elsewhere. The HIP process is based on the procedures that have been used to develop the formed HIP can process, including the baseline process developed at Idaho National Laboratory (INL). The HIP bonding cladding process development is summarized in the listed references. Further iterations with Babcock & Wilcox (B&W) to refine the process to meet production and facility requirements is expected.

  7. Heavy oils processing materials requirements crude processing

    Energy Technology Data Exchange (ETDEWEB)

    Sloley, Andrew W. [CH2M Hill, Englewood, CO (United States)


    Over time, recommended best practices for crude unit materials selection have evolved to accommodate new operating requirements, feed qualities, and product qualities. The shift to heavier oil processing is one of the major changes in crude feed quality occurring over the last 20 years. The three major types of crude unit corrosion include sulfidation attack, naphthenic acid attack, and corrosion resulting from hydrolyzable chlorides. Heavy oils processing makes all three areas worse. Heavy oils have higher sulfur content; higher naphthenic acid content; and are more difficult to desalt, leading to higher chloride corrosion rates. Materials selection involves two major criteria, meeting required safety standards, and optimizing economics of the overall plant. Proper materials selection is only one component of a plant integrity approach. Materials selection cannot eliminate all corrosion. Proper materials selection requires appropriate support from other elements of an integrity protection program. The elements of integrity preservation include: materials selection (type and corrosion allowance); management limits on operating conditions allowed; feed quality control; chemical additives for corrosion reduction; and preventive maintenance and inspection (PMI). The following discussion must be taken in the context of the application of required supporting work in all the other areas. Within that context, specific materials recommendations are made to minimize corrosion due to the most common causes in the crude unit. (author)

  8. Stimulus Intensity-dependent Modulations of Hippocampal Long-term Potentiation by Basolateral Amygdala Priming

    Directory of Open Access Journals (Sweden)

    Zexuan eLi


    Full Text Available There is growing realization that the relationship between memory and stress/emotionality is complicated, and may include both memory enhancing and memory impairing aspects. It has been suggested that the underlying mechanisms involve amygdalar modulation of hippocampal synaptic plasticity, such as long-term potentiation (LTP. We recently reported that while in CA1 basolateral amygdala (BLA priming impaired theta stimulation induced LTP, it enhanced LTP in the dentate gyrus (DG. However, emotional and stressfull experiences were found to activate synaptic plasticity within the BLA, rasing the possibility that BLA modulation of other brain regions may be altered as well, as it may depend on the way the BLA is activated or is responding. In previous studies BLA priming stimulation was relatively weak (1V, 50 µs pulse duration. In the present study we assessed the effects of two stronger levels of BLA priming stimulation (1V or 2V, 100 µs pulse duration on LTP induction in hippocampal DG and CA1, in anesthetized rats. Results show that 1V-BLA priming stimulation enhanced but 2V-BLA priming stimulation impaired DG LTP; however, both levels of BLA priming stimulation impaired CA1 LTP, suggesting that modulation of hippocampal synaptic plasticity by amygdala is dependent on the degree of amygdala activation. These findings suggest that plasticity induced within the amygdala, by stressful experiences induces a form of metaplasticity that would alter the way the amygdala may modulate memory-related processes in other brain areas, such as the hippocampus.

  9. The Isasmelt process

    Energy Technology Data Exchange (ETDEWEB)

    Barrett, K.R. (MIM Technology Marketing Ltd., Northfleet (United Kingdom))


    The Isasmelt process was developed at Mt Isa Mines Ltd. in Queensland. The process was initially developed for the treatment of lead concentrate. After successful application of the process to lead production a pilot plant was built for the treatment of copper concentrate to produce copper matte. This was successful and as a result Mt Isa Mines decided to build a new copper smelter with a capacity of 180,000 t copper/ a in copper matte. Further commercialisation of the process has resulted in the construction of further plants for lead, nickel and copper production. Mt Isa Mines Ltd. has been associated with CSIRO (Commonwealth Scientific Industrial Research Organisation) in the development of the Isasmelt process since 1977, when a Sirosmelt lance was tested for reducing copper converter slags. Thermodynamic modelling and cruicible scale investigations on a lead smelting process were initiated in 1978. After further work on a 120 kg/h pilot plant the Isasmelt process for lead concentrate smelting was patented jointly by Mt Isa Mines and CSIRO. Since then a 5 t/h demonstration plant was commissioned 1983/85 for smelting and reduction. Finally in 1991 a commercial scale plant with a capacity of 60,000 t/a was commissioned. (orig.).

  10. Revealing the programming process

    DEFF Research Database (Denmark)

    Bennedsen, Jens; Caspersen, Michael Edelgaard


    One of the most important goals of an introductory programming course is that the students learn a systematic approach to the development of computer programs. Revealing the programming process is an important part of this; however, textbooks do not address the issue -- probably because the textb......One of the most important goals of an introductory programming course is that the students learn a systematic approach to the development of computer programs. Revealing the programming process is an important part of this; however, textbooks do not address the issue -- probably because...... the textbook medium is static and therefore ill-suited to expose the process of programming. We have found that process recordings in the form of captured narrated programming sessions are a simple, cheap, and efficient way of providing the revelation.We identify seven different elements of the programming...... process for which process recordings are a valuable communication media in order to enhance the learning process. Student feedback indicates both high learning outcome and superior learning potential compared to traditional classroom teaching....

  11. States in Process Calculi

    Directory of Open Access Journals (Sweden)

    Christoph Wagner


    Full Text Available Formal reasoning about distributed algorithms (like Consensus typically requires to analyze global states in a traditional state-based style. This is in contrast to the traditional action-based reasoning of process calculi. Nevertheless, we use domain-specific variants of the latter, as they are convenient modeling languages in which the local code of processes can be programmed explicitly, with the local state information usually managed via parameter lists of process constants. However, domain-specific process calculi are often equipped with (unlabeled reduction semantics, building upon a rich and convenient notion of structural congruence. Unfortunately, the price for this convenience is that the analysis is cumbersome: the set of reachable states is modulo structural congruence, and the processes' state information is very hard to identify. We extract from congruence classes of reachable states individual state-informative representatives that we supply with a proper formal semantics. As a result, we can now freely switch between the process calculus terms and their representatives, and we can use the stateful representatives to perform assertional reasoning on process calculus models.

  12. Semi-Markov processes

    CERN Document Server



    Semi-Markov Processes: Applications in System Reliability and Maintenance is a modern view of discrete state space and continuous time semi-Markov processes and their applications in reliability and maintenance. The book explains how to construct semi-Markov models and discusses the different reliability parameters and characteristics that can be obtained from those models. The book is a useful resource for mathematicians, engineering practitioners, and PhD and MSc students who want to understand the basic concepts and results of semi-Markov process theory. Clearly defines the properties and

  13. Transnational Learning Processes

    DEFF Research Database (Denmark)

    Nedergaard, Peter

    This paper analyses and compares the transnational learning processes in the employment field in the European Union and among the Nordic countries. Based theoretically on a social constructivist model of learning and methodologically on a questionnaire distributed to the relevant participants......, a number of hypotheses concerning transnational learning processes are tested. The paper closes with a number of suggestions regarding an optimal institutional setting for facilitating transnational learning processes.Key words: Transnational learning, Open Method of Coordination, Learning, Employment......, European Employment Strategy, European Union, Nordic countries....

  14. Plasma processing for VLSI

    CERN Document Server

    Einspruch, Norman G


    VLSI Electronics: Microstructure Science, Volume 8: Plasma Processing for VLSI (Very Large Scale Integration) discusses the utilization of plasmas for general semiconductor processing. It also includes expositions on advanced deposition of materials for metallization, lithographic methods that use plasmas as exposure sources and for multiple resist patterning, and device structures made possible by anisotropic etching.This volume is divided into four sections. It begins with the history of plasma processing, a discussion of some of the early developments and trends for VLSI. The second section

  15. Getting Started with Processing

    CERN Document Server

    Reas, Casey


    Learn computer programming the easy way with Processing, a simple language that lets you use code to create drawings, animation, and interactive graphics. Programming courses usually start with theory, but this book lets you jump right into creative and fun projects. It's ideal for anyone who wants to learn basic programming, and serves as a simple introduction to graphics for people with some programming skills. Written by the founders of Processing, this book takes you through the learning process one step at a time to help you grasp core programming concepts. You'll learn how to sketch wi

  16. Chemical Processing Manual (United States)

    Beyerle, F. J.


    Chemical processes presented in this document include cleaning, pickling, surface finishes, chemical milling, plating, dry film lubricants, and polishing. All types of chemical processes applicable to aluminum, for example, are to be found in the aluminum alloy section. There is a separate section for each category of metallic alloy plus a section for non-metals, such as plastics. The refractories, super-alloys and titanium, are prime candidates for the space shuttle, therefore, the chemical processes applicable to these alloys are contained in individual sections of this manual.

  17. The image processing handbook

    CERN Document Server

    Russ, John C


    Now in its fifth edition, John C. Russ's monumental image processing reference is an even more complete, modern, and hands-on tool than ever before. The Image Processing Handbook, Fifth Edition is fully updated and expanded to reflect the latest developments in the field. Written by an expert with unequalled experience and authority, it offers clear guidance on how to create, select, and use the most appropriate algorithms for a specific application. What's new in the Fifth Edition? ·       A new chapter on the human visual process that explains which visual cues elicit a response from the vie

  18. Study on Glulam Process

    Institute of Scientific and Technical Information of China (English)

    PENG Limin; WANG Haiqing; HE Weili


    This paper selected lumbers of Manchurian ash (Fraxinus rnandshurica), Manchurian walnut (Juglans mandshuricd) and Spruce (Picea jezoensis vai.kornamvii) for manufacturing glulam with water-borne polymeric-isocyanate adhesive to determine process variables. The process variables that include specific pressure, pressing time and adhesive application amount influencing the shear strength of the glulam, were investigated through the orthogonal test. The results indicated that optimum process variables for glulam manufacturing were as follows: Specific pressure of 1.5 MPa for Spruce and 2,0 MPa both for Manchurian ash and Manchurian walnut, pressing time of 60 min and adhesive application amount of 250 g/m2.

  19. Digital Differential Geometry Processing

    Institute of Scientific and Technical Information of China (English)

    Xin-Guo Liu; Hu-Jun Bao; Qun-Sheng Peng


    The theory and methods of digital geometry processing has been a hot research area in computer graphics, as geometric models serves as the core data for 3D graphics applications. The purpose of this paper is to introduce some recent advances in digital geometry processing, particularly mesh fairing, surface parameterization and mesh editing, that heavily use differential geometry quantities. Some related concepts from differential geometry, such as normal, curvature, gradient,Laplacian and their counterparts on digital geometry are also reviewed for understanding the strength and weakness of various digital geometry processing methods.

  20. Nano integrated circuit process

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yung Sup


    This book contains nine chapters, which are introduction of manufacture of semiconductor chip, oxidation such as Dry-oxidation, wet oxidation, oxidation model and oxide film, diffusion like diffusion process, diffusion equation, diffusion coefficient and diffusion system, ion implantation, including ion distribution, channeling, multiimplantation and masking and its system, sputtering such as CVD and PVD, lithography, wet etch and dry etch, interconnection and flattening like metal-silicon connection, silicide, multiple layer metal process and flattening, an integrated circuit process, including MOSFET and CMOS.

  1. Irreversible processes kinetic theory

    CERN Document Server

    Brush, Stephen G


    Kinetic Theory, Volume 2: Irreversible Processes deals with the kinetic theory of gases and the irreversible processes they undergo. It includes the two papers by James Clerk Maxwell and Ludwig Boltzmann in which the basic equations for transport processes in gases are formulated, together with the first derivation of Boltzmann's ""H-theorem"" and a discussion of this theorem, along with the problem of irreversibility.Comprised of 10 chapters, this volume begins with an introduction to the fundamental nature of heat and of gases, along with Boltzmann's work on the kinetic theory of gases and s

  2. Ultrasonic Processing of Materials (United States)

    Han, Qingyou


    Irradiation of high-energy ultrasonic vibration in metals and alloys generates oscillating strain and stress fields in solids, and introduces nonlinear effects such as cavitation, acoustic streaming, and radiation pressure in molten materials. These nonlinear effects can be utilized to assist conventional material processing processes. This article describes recent research at Oak Ridge National Labs and Purdue University on using high-intensity ultrasonic vibrations for degassing molten aluminum, processing particulate-reinforced metal matrix composites, refining metals and alloys during solidification process and welding, and producing bulk nanostructures in solid metals and alloys. Research results suggest that high-intensity ultrasonic vibration is capable of degassing and dispersing small particles in molten alloys, reducing grain size during alloy solidification, and inducing nanostructures in solid metals.

  3. Processer i undervisningen

    DEFF Research Database (Denmark)

    Bundsgaard, Jeppe

    Undersøgelsen har fokus på processer i undervisningen – og derigennem på hvordan digitale læremidler kan understøtte eller integreres i typiske processer. Undersøgelsen hviler på deltagende observation på Abildgårdskolen i Odense. Gennem observationerne er der identificeret en række eksempler på ...... udfordringer for at gennemføre de undervisningsmæssige processer og givet bud på digitale læremidler der forventes at kunne understøtte processerne. Undersøgelsen viser samtidig hvordan fokus på processer kan fungere som en metode til brugerdreven innovation....

  4. Processed Products Database System (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection of annual data on processed seafood products. The Division provides authoritative advice, coordination and guidance on matters related to the collection,...

  5. Reconfigurable network processing platforms

    NARCIS (Netherlands)

    Kachris, C.


    This dissertation presents our investigation on how to efficiently exploit reconfigurable hardware to design flexible, high performance, and power efficient network devices capable to adapt to varying processing requirements of network applications and traffic. The proposed reconfigurable network pr

  6. Quantum processes in semiconductors

    CERN Document Server

    Ridley, B K


    Aimed at graduate students, this is a guide to quantum processes of importance in the physics and technology of semiconductors. The fifth edition includes new chapters that expand the coverage of semiconductor physics relevant to its accompanying technology.


    Evaporation has been an established technology in the metal finishing industry for many years. In this process, wastewaters containing reusable materials, such as copper, nickel, or chromium compounds are heated, producing a water vapor that is continuously removed and condensed....

  8. Phenol removal pretreatment process (United States)

    Hames, Bonnie R.


    A process for removing phenols from an aqueous solution is provided, which comprises the steps of contacting a mixture comprising the solution and a metal oxide, forming a phenol metal oxide complex, and removing the complex from the mixture.

  9. Logistics Innovation Process Revisited

    DEFF Research Database (Denmark)

    Gammelgaard, Britta; Su, Shong-Iee Ivan; Yang, Su-Lan


    Purpose – The purpose of this paper is to learn more about logistics innovation processes and their implications for the focal organization as well as the supply chain, especially suppliers. Design/methodology/approach – The empirical basis of the study is a longitudinal action research project...... that was triggered by the practical needs of new ways of handling material flows of a hospital. This approach made it possible to revisit theory on logistics innovation process. Findings – Apart from the tangible benefits reported to the case hospital, five findings can be extracted from this study: the logistics...... innovation process model may include not just customers but also suppliers; logistics innovation in buyer-supplier relations may serve as an alternative to outsourcing; logistics innovation processes are dynamic and may improve supplier partnerships; logistics innovations in the supply chain are as dependent...


    Directory of Open Access Journals (Sweden)

    Yu. Taranenko


    Full Text Available The article deals with the theoretical basis of the simulation. The study shows the simulation of logistic processes in industrial countries is an integral part of many economic projects aimed at the creation or improvement of logistics systems. The paper was used model Beer Game for management of logistics processes in the enterprise. The simulation model implements in AnyLogic package. AnyLogic product allows us to consider the logistics processes as an integrated system, which allows reaching better solutions. Logistics process management involves pooling the sales market, production and distribution to ensure the temporal level of customer service at the lowest cost overall. This made it possible to conduct experiments and to determine the optimal size of the warehouse at the lowest cost.

  11. Ultrahigh bandwidth signal processing

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo


    Optical time lenses have proven to be very versatile for advanced optical signal processing. Based on a controlled interplay between dispersion and phase-modulation by e.g. four-wave mixing, the processing is phase-preserving, an hence useful for all types of data signals including coherent multi......-level modulation founats. This has enabled processing of phase-modulated spectrally efficient data signals, such as orthogonal frequency division multiplexed (OFDM) signa In that case, a spectral telescope system was used, using two time lenses with different focal lengths (chirp rates), yielding a spectral...... regeneratio These operations require a broad bandwidth nonlinear platform, and novel photonic integrated nonlinear platform like aluminum gallium arsenide nano-waveguides used for 1.28 Tbaud optical signal processing will be described....

  12. Radiation processing in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment


    Economic scale of radiation application in the field of industry, agriculture and medicine in Japan in 1997 was investigated to compare its economic impacts with that of nuclear energy industry. Total production value of radiation application accounted for 54% of nuclear industry including nuclear energy industry and radiation applications in three fields above. Industrial radiation applications were further divided into five groups, namely nondestructive test, RI instruments, radiation facilities, radiation processing and ion beam processing. More than 70% of the total production value was brought about by ion beam processing for use with IC and semiconductors. Future economic prospect of radiation processing of polymers, for example cross-linking, EB curing, graft polymerization and degradation, is reviewed. Particular attention was paid to radiation vulcanization of natural rubber latex and also to degradation of natural polymers. (S. Ohno)

  13. IT Project Prioritization Process

    DEFF Research Database (Denmark)

    Shollo, Arisa; Constantiou, Ioanna


    In most of the large companies IT project prioritization process is designed based on principles of evidencebased management. We investigate a case of IT project prioritization in a financial institution, and in particular, how managers practice evidence-based management during this process. We use...... a rich dataset built from a longitudinal study of the prioritization process for the IT projects. Our findings indicate that managers reach a decision not only by using evidence but from the interplay between the evidence and the judgment devices that managers employ. The interplay between evidence...... and judgment devices is manifested in three ways: supplementing, substituting, and interpreting evidence. We show that while evidence does not fully determine the decision, it plays a central role in discussions, reflections, and negotiations during the IT prioritization process....

  14. Cooperative processing data bases (United States)

    Hasta, Juzar


    Cooperative processing for the 1990's using client-server technology is addressed. The main theme is concepts of downsizing from mainframes and minicomputers to workstations on a local area network (LAN). This document is presented in view graph form.


    Directory of Open Access Journals (Sweden)

    Igor G. Fedorov


    Full Text Available We can be mistaken to formulate basic concepts of process management, and we are at risk to be on the wrong way solving the focused problems – instead of process management we could do automatization, instead of process system we could introduce function-oriented system. Without having a clear idea of the model we have to execute, we can plan this model as an analytical one and do not include all the necessary tools for management on the stage of planning. The article is targeted for the analysts who have skills in analytical modeling of business processes and would like to make a step forward to the implementation of these models. In order to become professionals in this field it is necessary to learn the terminology, first of all. 

  16. Essentials of stochastic processes

    CERN Document Server

    Durrett, Richard


    Building upon the previous editions, this textbook is a first course in stochastic processes taken by undergraduate and graduate students (MS and PhD students from math, statistics, economics, computer science, engineering, and finance departments) who have had a course in probability theory. It covers Markov chains in discrete and continuous time, Poisson processes, renewal processes, martingales, and option pricing. One can only learn a subject by seeing it in action, so there are a large number of examples and more than 300 carefully chosen exercises to deepen the reader’s understanding. Drawing from teaching experience and student feedback, there are many new examples and problems with solutions that use TI-83 to eliminate the tedious details of solving linear equations by hand, and the collection of exercises is much improved, with many more biological examples. Originally included in previous editions, material too advanced for this first course in stochastic processes has been eliminated while treatm...

  17. Assessing Process and Product

    DEFF Research Database (Denmark)

    Bennedsen, Jens; Caspersen, Michael E.


    The final assessment of a course must reflect its goals, and contents. An important goal of our introductory programming course is that the students learn a systematic approach for the development of computer programs. Having the programming process as learning objective naturally raises the ques......The final assessment of a course must reflect its goals, and contents. An important goal of our introductory programming course is that the students learn a systematic approach for the development of computer programs. Having the programming process as learning objective naturally raises...... the question how to include this in assessments. Traditional assessments (e.g. oral, written, or multiple choice) are unsuitable to test the programming process. We describe and evaluate a practical lab examination that assesses the students' programming process as well as the developed programs...

  18. Markovian risk process

    Institute of Scientific and Technical Information of China (English)

    WANG Han-xing; YAN Yun-zhi; ZHAO Fei; FANG Da-fan


    A Markovian risk process is considered in this paper, which is the generalization of the classical risk model. It is proper that a risk process with large claims is modelled as the Markovian risk model. In such a model, the occurrence of claims is described by a point process {N(t)}t≥o with N(t) being the number of jumps during the interval (0, t] for a Markov jump process. The ruin probability Ψ(u) of a company facing such a risk model is mainly studied. An integral equation satisfied by the ruin probability function Ψ(u) is obtained and the bounds for the convergence rate of the ruin probability Ψ(u) are given by using a generalized renewal technique developed in the paper.

  19. Fractional Pure Birth Processes

    CERN Document Server

    Orsingher, Enzo; 10.3150/09-BEJ235


    We consider a fractional version of the classical non-linear birth process of which the Yule-Furry model is a particular case. Fractionality is obtained by replacing the first-order time derivative in the difference-differential equations which govern the probability law of the process, with the Dzherbashyan-Caputo fractional derivative. We derive the probability distribution of the number $ \\mathcal{N}_\

  20. Harmonizable Processes: Structure. (United States)


    a related result of Thomas ([39], p. 146). However, the Bourbaki set up of these papers is inconvenient here, and they will be converted to the set ...of processes. 1 2 2i 1. Introduction. Recently there have been significant attempts for extending the well-understood theory of stationary processes...characterizations of the respective classes. This involves a free use of some elementary aspects of vector measure theory ; and it already raises some interesting

  1. Process for compound transformation

    KAUST Repository

    Basset, Jean-Marie


    Embodiments of the present disclosure provide for methods of using a catalytic system to chemically transform a compound (e.g., a hydrocarbon). In an embodiment, the method does not employ grafting the catalyst prior to catalysis. In particular, embodiments of the present disclosure provide for a process of hydrocarbon (e.g., C1 to C20 hydrocarbon) metathesis (e.g., alkane, olefin, or alkyne metathesis) transformation, where the process can be conducted without employing grafting prior to catalysis.

  2. Digital signal processing: Handbook (United States)

    Goldenberg, L. M.; Matiushkin, B. D.; Poliak, M. N.

    The fundamentals of the theory and design of systems and devices for the digital processing of signals are presented. Particular attention is given to algorithmic methods of synthesis and digital processing equipment in communication systems (e.g., selective digital filtering, spectral analysis, and variation of the signal discretization frequency). Programs for the computer-aided analysis of digital filters are described. Computational examples are presented, along with tables of transfer function coefficients for recursive and nonrecursive digital filters.

  3. Diasporic Relationships and Processes

    DEFF Research Database (Denmark)

    Singla, Rashmi


    How does moving across the geographical borders affect the relationships of diaspora members both here – in the country of residence and there- in the country of origin? The article delineates some of the processes through gendered experiences of the young adults perceived as active actors based...... an empirical longitudinal study. The results indicate transformations in belongings and longings indicating reinterpretation of the self, others and home in context of exclusion processes at various levels....

  4. Bank Record Processing (United States)


    Barnett Banks of Florida, Inc. operates 150 banking offices in 80 Florida cities. Banking offices have computerized systems for processing deposits or withdrawals in checking/savings accounts, and for handling commercial and installment loan transactions. In developing a network engineering design for the terminals used in record processing, an affiliate, Barnett Computing Company, used COSMIC's STATCOM program. This program provided a reliable network design tool and avoided the cost of developing new software.

  5. Poststroke neuroplasticity processes

    Directory of Open Access Journals (Sweden)

    I. V. Damulin


    Full Text Available The paper considers different aspects of neuroplasticity in patients with stroke. It underlines the dynamism of this process and the ambiguity of involvement of the structures of the contralateral cerebral hemisphere in the restorative process. It considers the periods after onset of stroke and the activation of different brain regions (of both the involved and intact hemisphere in the poststroke period. Particular emphasis is placed on the issues of neurorehabilitation in this category of patients. Delay in rehabilitation measures leads to a worse outcome, the patients must be at hospital longer. It is emphasized that the neurorehabilitaton measures should use strategies aimed at improving plasticity processes at the level of synaptic transmission and neuronal communications. At the same time, of great importance are the processes of structural and functional remodeling of neuronal communications with the involvement of surviving neurons that are located in the peri-infarct area and partially damaged during ischemia. To recover stroke-induced lost motor functions, measures are implemented to modulate the ipsilateral motor cortex, contralateral motor cortex, and sensory afferentation. Remodeling processes, one of the manifestations of neuroplasticity, vary with the size and location of an ischemic focus. The specific features of this process with subcortical and cortical foci are considered. It is stressed that there are genetically determined neurotrophic factors that may enhance remodeling processes in the peri-infarct area, as well as factors that inhibit these processes. The sensory system is noted to have a high potential of compensation, which is appreciably associated with the considerable extent of sensory fibers even at the level of the cerebral cortex.

  6. Cognitive Processes in Writing

    Institute of Scientific and Technical Information of China (English)



    Writing has become one of important topic to discuss in the new age.Its theories could be generally learnt,but its nature needs to handle in specific contents.In another words,every one who can write must generate his/her thinking or cognitive processes.Because writing thinking is to do meaningful activities,how to solove writing problems could be managed through cognitive process.

  7. Apple Image Processing Educator (United States)

    Gunther, F. J.


    A software system design is proposed and demonstrated with pilot-project software. The system permits the Apple II microcomputer to be used for personalized computer-assisted instruction in the digital image processing of LANDSAT images. The programs provide data input, menu selection, graphic and hard-copy displays, and both general and detailed instructions. The pilot-project results are considered to be successful indicators of the capabilities and limits of microcomputers for digital image processing education.

  8. Metoda Analytic Network Process



    The thesis is concerned with Multi-Criteria Decision Making, in particular the Analytic Network Process method. The introductory part is dedicated to compile all the theory necessary to understand the method and utilized throughout the paper. The Analytic Hierarchy Process method is described and later generalized in the form of the ANP. Part of the paper is a description of available software products that are able to solve the ANP models. The main focus is on the application of the method, ...

  9. Biomedical signal processing

    CERN Document Server

    Akay, Metin


    Sophisticated techniques for signal processing are now available to the biomedical specialist! Written in an easy-to-read, straightforward style, Biomedical Signal Processing presents techniques to eliminate background noise, enhance signal detection, and analyze computer data, making results easy to comprehend and apply. In addition to examining techniques for electrical signal analysis, filtering, and transforms, the author supplies an extensive appendix with several computer programs that demonstrate techniques presented in the text.

  10. Cauchy cluster process

    DEFF Research Database (Denmark)

    Ghorbani, Mohammad


    In this paper we introduce an instance of the well-know Neyman–Scott cluster process model with clusters having a long tail behaviour. In our model the offspring points are distributed around the parent points according to a circular Cauchy distribution. Using a modified Cramér-von Misses test st...... statistic and the simulated pointwise envelopes it is shown that this model fits better than the Thomas process to the frequently analyzed long-leaf pine data-set....

  11. Scramjet Combustion Processes (United States)


    plan for these flights is as follows: Scramjet Combustion Processes RTO-EN-AVT-185 11 - 21 HyShot 5 – A Free-Flying Hypersonic Glider HyShot...5 will be a hypersonic glider designed to fly at Mach 8. It will separate from its rocket booster in space and perform controlled manoeuvres as it...RTO-EN-AVT-185 11 - 1 Scramjet Combustion Processes Michael Smart and Ray Stalker Centre for Hypersonics The University of Queensland

  12. Solution Processing - Rodlike Polymers (United States)


    side it necessary and identify by block number) Para-ordered Polymers High Modulus Fibers and Films Polybenzobisoxazoles Polybenzobisthiazoles 20...considerations important in solution processing are considered, with special emphasis on the dry-jet wet spinning process used to form fibers . Pertinent...Company, Summit, N.J. iii TABLE OF CONTENTS 1. INTRODUCTION ................ .......................... .. 1 2. REMARKS ON DRY-JET WET SPUN FIBER

  13. Image Processing Software (United States)


    To convert raw data into environmental products, the National Weather Service and other organizations use the Global 9000 image processing system marketed by Global Imaging, Inc. The company's GAE software package is an enhanced version of the TAE, developed by Goddard Space Flight Center to support remote sensing and image processing applications. The system can be operated in three modes and is combined with HP Apollo workstation hardware.

  14. The Integrated Renovation Process

    DEFF Research Database (Denmark)

    Galiotto, Nicolas; Heiselberg, Per; Knudstrup, Mary-Ann

    The Integrated Renovation Process (IRP) is a user customized methodology based on judiciously selected constructivist and interactive multi-criteria decision making methods (Galiotto, Heiselberg, & Knudstrup, 2014 (expected)). When applied for home renovation, the Integrated Renovation Process...... for the quantitative analyses and the generation of the renovation scenarios so they get more time for the cost optimisation and the qualitative analysis of the homeowners’ needs, wishes and behaviours....

  15. Privatisation Process in Kosovo

    Directory of Open Access Journals (Sweden)

    Dr.Sc. Hysni Terziu


    Full Text Available This paper aims at analysing activities of the privatisation process in Kosovo, seeing that privatisation is treated as a fundamental factor of overall transformation of the whole society. It may be established that the primary aim of privatisation process is increasing economic efficiency, reflection of the current state and directions of development in general. Privatisation as a process has as primary aim of opening new areas of freedom, economic efficiency and individualism. Key aim of privatisation process in Kosovo must be increase of economic efficiency, preservation of the healthy economic potential created up to date, and ensuring of the long term concept, which enables growth and macroeconomic stability. The policy of privatisation should give a response related to strategic aspects of privatisation of these sectors: of models, procedures, potential investors, technological modernisation and overtaking of social barriers. Process of privatisation and transition which has now covered countries of the Eastern and Central Europe, aims at profound economic and political transformation of these countries. To achieve this, it is necessarily required to have some basic preconditions, which are related to incitement of general efficiency of the enterprises, expansion of the capital market, introduction of competition, development of business culture in private property and freedom of entrepreneurship. Impacts of privatisation in economic development of Kosovo take a considerable place compared to other countries, therefore our aim is that through this paper we analyse factors and methods of implementation in this process.

  16. PALSAR ground data processing (United States)

    Frick, Heinrich; Palsetia, Marzban; Carande, Richard; Curlander, James C.


    The upcoming launches of new satellites like ALOS, Envisat, Radarsat2 and ECHO will pose a significant challenge for many ground stations, namely to integrate new SAR processing software into their existing systems. Vexcel Corporation in Boulder, Colorado, has built a SAR processing system, named APEX -Suite, for spaceborne SAR satellites that can easily be expanded for the next generation of SAR satellites. APEX-Suite includes an auto-satellite-detecting Level 0 Processor that includes bit-error correction, data quality characterization, and as a unique feature, a sophisticated and very accurate Doppler centroid estimator. The Level 1 processing is divided into the strip mode processor FOCUST, based on the well-proven range-Doppler algorithm, and the SWATHT ScanSAR processor that uses the Chirp Z Trans-form algorithm. A high-accuracy ortho-rectification processor produces systematic and precision corrected Level 2 SAR image pro ducts. The PALSAR instrument is an L-band SAR with multiple fine and standard resolution beams in strip mode, and several wide-swath ScanSAR modes. We will address the adaptation process of Vexcel's APEX-Suite processing system for the PALSAR sensor and discuss image quality characteristics based on processed simulated point target phase history data.

  17. Helium process cycle (United States)

    Ganni, Venkatarao


    A unique process cycle and apparatus design separates the consumer (cryogenic) load return flow from most of the recycle return flow of a refrigerator and/or liquefier process cycle. The refrigerator and/or liquefier process recycle return flow is recompressed by a multi-stage compressor set and the consumer load return flow is recompressed by an independent consumer load compressor set that maintains a desirable constant suction pressure using a consumer load bypass control valve and the consumer load return pressure control valve that controls the consumer load compressor's suction pressure. The discharge pressure of this consumer load compressor is thereby allowed to float at the intermediate pressure in between the first and second stage recycle compressor sets. Utilizing the unique gas management valve regulation, the unique process cycle and apparatus design in which the consumer load return flow is separate from the recycle return flow, the pressure ratios of each recycle compressor stage and all main pressures associated with the recycle return flow are allowed to vary naturally, thus providing a naturally regulated and balanced floating pressure process cycle that maintains optimal efficiency at design and off-design process cycle capacity and conditions automatically.

  18. Novel food processing techniques

    Directory of Open Access Journals (Sweden)

    Vesna Lelas


    Full Text Available Recently, a lot of investigations have been focused on development of the novel mild food processing techniques with the aim to obtain the high quality food products. It is presumed also that they could substitute some of the traditional processes in the food industry. The investigations are primarily directed to usage of high hydrostatic pressure, ultrasound, tribomechanical micronization, microwaves, pulsed electrical fields. The results of the scientific researches refer to the fact that application of some of these processes in particular food industry can result in lots of benefits. A significant energy savings, shortening of process duration, mild thermal conditions, food products with better sensory characteristics and with higher nutritional values can be achieved. As some of these techniques act also on the molecular level changing the conformation, structure and electrical potential of organic as well as inorganic materials, the improvement of some functional properties of these components may occur. Common characteristics of all of these techniques are treatment at ambient or insignificant higher temperatures and short time of processing (1 to 10 minutes. High hydrostatic pressure applied to various foodstuffs can destroy some microorganisms, successfully modify molecule conformation and consequently improve functional properties of foods. At the same time it acts positively on the food products intend for freezing. Tribomechanical treatment causes micronization of various solid materials that results in nanoparticles and changes in structure and electrical potential of molecules. Therefore, the significant improvement of some rheological and functional properties of materials occurred. Ultrasound treatment proved to be potentially very successful technique of food processing. It can be used as a pretreatment to drying (decreases drying time and improves functional properties of food, as extraction process of various components

  19. Carbon dioxide reducing processes; Koldioxidreducerande processer

    Energy Technology Data Exchange (ETDEWEB)

    Svensson, Fredrik


    This thesis discusses different technologies to reduce or eliminate the carbon dioxide emissions, when a fossil fuel is used for energy production. Emission reduction can be accomplished by separating the carbon dioxide for storage or reuse. There are three different ways of doing the separation. The carbon dioxide can be separated before the combustion, the process can be designed so that the carbon dioxide can be separated without any energy consumption and costly systems or the carbon dioxide can be separated from the flue gas stream. Two different concepts of separating the carbon dioxide from a combined cycle are compared, from the performance and the economical point of view, with a standard natural gas fired combined cycle where no attempts are made to reduce the carbon dioxide emissions. One concept is to use absorption technologies to separate the carbon dioxide from the flue gas stream. The other concept is based on a semi-closed gas turbine cycle using carbon dioxide as working fluid and combustion with pure oxygen, generated in an air-separating unit. The calculations show that the efficiency (power) drop is smaller for the first concept than for the second, 8.7 % points compared to 13.7 % points, when power is produced. When both heat and power are produced, the relation concerning the efficiency (power) remains. Regarding the overall efficiency (heat and power) the opposite relation is present. A possible carbon dioxide tax must exceed 0.21 SEK/kg CO{sub 2} for it to be profitable to separate carbon dioxide with any of these technologies.

  20. Customer Innovation Process Leadership

    DEFF Research Database (Denmark)

    Lindgren, Peter; Jørgensen, Jacob Høj; Goduscheit, René Chester


    Innovation leadership has traditionally been focused on leading the companies' product development fast, cost effectively and with an optimal performance driven by technological inventions or by customers´ needs. To improve the efficiency of the product development process focus has been on diffe......Innovation leadership has traditionally been focused on leading the companies' product development fast, cost effectively and with an optimal performance driven by technological inventions or by customers´ needs. To improve the efficiency of the product development process focus has been...... to handle shorter and faster product life cycles. Continuously changing customer needs are pushing companies' competence of continuous innovation to a maximum - but still this seems not to be enough to stay competitive on the global market and reach the goals of growth. This article therefore suggests...... another outlook to future innovation leadership - Customer Innovation Process Leadership - CIP-leadership. CIP-leadership moves the company's innovation process closer to the customer innovation process and discusses how companies can be involved and innovate in customers' future needs and lead...

  1. VLSI signal processing technology

    CERN Document Server

    Swartzlander, Earl


    This book is the first in a set of forthcoming books focussed on state-of-the-art development in the VLSI Signal Processing area. It is a response to the tremendous research activities taking place in that field. These activities have been driven by two factors: the dramatic increase in demand for high speed signal processing, especially in consumer elec­ tronics, and the evolving microelectronic technologies. The available technology has always been one of the main factors in determining al­ gorithms, architectures, and design strategies to be followed. With every new technology, signal processing systems go through many changes in concepts, design methods, and implementation. The goal of this book is to introduce the reader to the main features of VLSI Signal Processing and the ongoing developments in this area. The focus of this book is on: • Current developments in Digital Signal Processing (DSP) pro­ cessors and architectures - several examples and case studies of existing DSP chips are discussed in...

  2. Due process traditionalism. (United States)

    Sunstein, Cass R


    In important cases, the Supreme Court has limited the scope of "substantive due process" by reference to tradition, but it has yet to explain why it has done so. Due process traditionalism might be defended in several distinctive ways. The most ambitious defense draws on a set of ideas associated with Edmund Burke and Friedrich Hayek, who suggested that traditions have special credentials by virtue of their acceptance by many minds. But this defense runs into three problems. Those who have participated in a tradition may not have accepted any relevant proposition; they might suffer from a systematic bias; and they might have joined a cascade. An alternative defense sees due process traditionalism as a second-best substitute for two preferable alternatives: a purely procedural approach to the Due Process Clause, and an approach that gives legislatures the benefit of every reasonable doubt. But it is not clear that in these domains, the first-best approaches are especially attractive; and even if they are, the second-best may be an unacceptably crude substitute. The most plausible defense of due process traditionalism operates on rule-consequentialist grounds, with the suggestion that even if traditions are not great, they are often good, and judges do best if they defer to traditions rather than attempting to specify the content of "liberty" on their own. But the rule-consequentialist defense depends on controversial and probably false assumptions about the likely goodness of traditions and the institutional incapacities of judges.

  3. Beyond the search process

    DEFF Research Database (Denmark)

    Hyldegård, Jette


    . It is concluded that the ISP-model does not fully comply with group members' problem solving process and the involved information seeking behavior. Further, complex academic problem solving seems to be even more complex when it is performed in a group based setting. The study contributes with a new conceptual......This paper reports on the findings from a longitudinal case study exploring Kuhlthau's information search process (ISP)-model in a group based academic setting. The research focus is on group members' activities and cognitive and emotional experiences during the task process of writing...... an assignment. It is investigated if group members' information behavior differ from the individual information seeker in the ISP-model and to what extent this behavior is influenced by contextual (work task) and social (group work) factors. Three groups of LIS students were followed during a 14 weeks period...

  4. Laser Processing and Chemistry

    CERN Document Server

    Bäuerle, Dieter


    This book gives an overview of the fundamentals and applications of laser-matter interactions, in particular with regard to laser material processing. Special attention is given to laser-induced physical and chemical processes at gas-solid, liquid-solid, and solid-solid interfaces. Starting with the background physics, the book proceeds to examine applications of lasers in “standard” laser machining and laser chemical processing (LCP), including the patterning, coating, and modification of material surfaces. This fourth edition has been enlarged to cover the rapid advances in the understanding of the dynamics of materials under the action of ultrashort laser pulses, and to include a number of new topics, in particular the increasing importance of lasers in various different fields of surface functionalizations and nanotechnology. In two additional chapters, recent developments in biotechnology, medicine, art conservation and restoration are summarized. Graduate students, physicists, chemists, engineers, a...

  5. Processes for xanthomonas biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Engelskirchen, K.; Stein, W.; Bahn, M.; Schieferstein, L.; Schindler, J.


    A process is described for producing xanthan gum in which the use of a stable, water-in-oil emulsion in the fermentation medium markedly lowers the viscosity of the medium, resulting in lower energy requirements for the process, and also resulting in enhanced yields of the biopolymer. In such an emulsion, the aqueous fermentation phase, with its microbial growth and metabolic processes, takes place in a finely dispersed homogeneous oil phase. The viscosity increase in each droplet of the aqueous nutrient solution will not noticeably affect this mixture in the fermenter because the viscosity of the reaction mixture in the fermenter is determined primarily by the viscosity of the oil phase. 45 claims

  6. Identification of wastewater processes

    DEFF Research Database (Denmark)

    Carstensen, Niels Jacob

    -known theory of the processes with the significant effects found in data. These models are called grey box models, and they contain rate expressions for the processes of influent load of nutrients, transport of nutrients between the aeration tanks, hydrolysis and growth of biomass, nitrification...... function. The grey box models are estimated on data sets from the Lundtofte pilot scale plant and the Aalborg West wastewater treatment plant. Estimation of Monod- kinetic expressions is made possible through the application of large data sets. Parameter extimates from the two plants show a reasonable......The introduction of on-line sensors for monitoring of nutrient salts concentrations on wastewater treatment plants with nutrient removal, opens a wide new area of modelling wastewater processes. The subject of this thesis is the formulation of operational dynamic models based on time series...

  7. Stochastic processes inference theory

    CERN Document Server

    Rao, Malempati M


    This is the revised and enlarged 2nd edition of the authors’ original text, which was intended to be a modest complement to Grenander's fundamental memoir on stochastic processes and related inference theory. The present volume gives a substantial account of regression analysis, both for stochastic processes and measures, and includes recent material on Ridge regression with some unexpected applications, for example in econometrics. The first three chapters can be used for a quarter or semester graduate course on inference on stochastic processes. The remaining chapters provide more advanced material on stochastic analysis suitable for graduate seminars and discussions, leading to dissertation or research work. In general, the book will be of interest to researchers in probability theory, mathematical statistics and electrical and information theory.

  8. Process window metrology (United States)

    Ausschnitt, Christopher P.; Chu, William; Hadel, Linda M.; Ho, Hok; Talvi, Peter


    This paper is the third of a series that defines a new approach to in-line lithography control. The first paper described the use of optically measurable line-shortening targets to enhance signal-to-noise and reduce measurement time. The second described the dual-tone optical critical dimension (OCD) measurement and analysis necessary to distinguish dose and defocus. Here we describe the marriage of dual-tone OCD to SEM-CD metrology that comprises what we call 'process window metrology' (PWM), the means to locate each measured site in dose and focus space relative to the allowed process window. PWM provides in-line process tracking and control essential to the successful implementation of low-k lithography.

  9. Quartz resonator processing system (United States)

    Peters, Roswell D. M.


    Disclosed is a single chamber ultra-high vacuum processing system for the oduction of hermetically sealed quartz resonators wherein electrode metallization and sealing are carried out along with cleaning and bake-out without any air exposure between the processing steps. The system includes a common vacuum chamber in which is located a rotatable wheel-like member which is adapted to move a plurality of individual component sets of a flat pack resonator unit past discretely located processing stations in said chamber whereupon electrode deposition takes place followed by the placement of ceramic covers over a frame containing a resonator element and then to a sealing stage where a pair of hydraulic rams including heating elements effect a metallized bonding of the covers to the frame.

  10. Process of timbral composing (United States)

    Withrow, Sam

    In this paper, I discuss the techniques and processes of timbral organization I developed while writing my chamber work, Afterimage. I compare my techniques with illustrative examples by other composers to place my work in historical context. I examine three elements of my composition process. The first is the process of indexing and cataloging basic sonic materials. The second consists of the techniques and mechanics of manipulating and assembling these collections into larger scale phrases, textures, and overall form in a musical work. The third element is the more elusive, and often extra-musical, source of inspiration and motivation. The evocative power of tone color is both immediately evident yet difficult to explain. What is timbre? This question cannot be answered solely in scientific terms; subjective factors affect our perception of it.

  11. The Nursing Process

    Directory of Open Access Journals (Sweden)

    M. Hammond


    Full Text Available The essence of the nursing process can be summed up in this quotation by Sir Francis Bacon: “Human knowledge and human powers meet in one; for where the cause is not known the effect cannot be produced.” Arriving at a concise, accurate definition of the nursing process was, for me, an impossible task. It is altogether too vast and too personal a topic to contract down into a niftylooking, we-pay-lip-service-to-it cliché. So what I propose to do is to present my understanding of the nursing process throughout this essay, and then to leave the reader with some overall, general impression of what it all entails.

  12. Quantum independent increment processes

    CERN Document Server

    Franz, Uwe


    This volume is the first of two volumes containing the revised and completed notes lectures given at the school "Quantum Independent Increment Processes: Structure and Applications to Physics". This school was held at the Alfried-Krupp-Wissenschaftskolleg in Greifswald during the period March 9 – 22, 2003, and supported by the Volkswagen Foundation. The school gave an introduction to current research on quantum independent increment processes aimed at graduate students and non-specialists working in classical and quantum probability, operator algebras, and mathematical physics. The present first volume contains the following lectures: "Lévy Processes in Euclidean Spaces and Groups" by David Applebaum, "Locally Compact Quantum Groups" by Johan Kustermans, "Quantum Stochastic Analysis" by J. Martin Lindsay, and "Dilations, Cocycles and Product Systems" by B.V. Rajarama Bhat.

  13. A support design process

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, J.; Scott, P.B. [Health and Safety Executive (United Kingdom)


    A workman suffered a fatal injury due to a fall of ground from the face of a development drivage, which was supported by passive supports supplemented with roof bolts. A working party was set up to review the support process and evaluate how protection of the workmen could be improved whilst setting supports.The working party included representatives from the trade unions, the mines inspectorate and mine operators.Visits were made to several mines and discussions were held with the workmen and management at these mines. The paper describes the results of the visits and how a support design process was evolved. The process will ensure that the support system is designed to reduce the inherent hazards associated with setting supports using either conventional or mixed support systems.

  14. Topological signal processing

    CERN Document Server

    Robinson, Michael


    Signal processing is the discipline of extracting information from collections of measurements. To be effective, the measurements must be organized and then filtered, detected, or transformed to expose the desired information.  Distortions caused by uncertainty, noise, and clutter degrade the performance of practical signal processing systems. In aggressively uncertain situations, the full truth about an underlying signal cannot be known.  This book develops the theory and practice of signal processing systems for these situations that extract useful, qualitative information using the mathematics of topology -- the study of spaces under continuous transformations.  Since the collection of continuous transformations is large and varied, tools which are topologically-motivated are automatically insensitive to substantial distortion. The target audience comprises practitioners as well as researchers, but the book may also be beneficial for graduate students.

  15. COTS software selection process.

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, William M. (Strike Wire Technologies, Louisville, CO); Lin, Han Wei; McClelland, Kelly (U.S. Security Associates, Livermore, CA); Ullrich, Rebecca Ann; Khanjenoori, Soheil; Dalton, Karen; Lai, Anh Tri; Kuca, Michal; Pacheco, Sandra; Shaffer-Gant, Jessica


    Today's need for rapid software development has generated a great interest in employing Commercial-Off-The-Shelf (COTS) software products as a way of managing cost, developing time, and effort. With an abundance of COTS software packages to choose from, the problem now is how to systematically evaluate, rank, and select a COTS product that best meets the software project requirements and at the same time can leverage off the current corporate information technology architectural environment. This paper describes a systematic process for decision support in evaluating and ranking COTS software. Performed right after the requirements analysis, this process provides the evaluators with more concise, structural, and step-by-step activities for determining the best COTS software product with manageable risk. In addition, the process is presented in phases that are flexible to allow for customization or tailoring to meet various projects' requirements.

  16. NTP comparison process (United States)

    Corban, Robert

    The systems engineering process for the concept definition phase of the program involves requirements definition, system definition, and consistent concept definition. The requirements definition process involves obtaining a complete understanding of the system requirements based on customer needs, mission scenarios, and nuclear thermal propulsion (NTP) operating characteristics. A system functional analysis is performed to provide a comprehensive traceability and verification of top-level requirements down to detailed system specifications and provides significant insight into the measures of system effectiveness to be utilized in system evaluation. The second key element in the process is the definition of system concepts to meet the requirements. This part of the process involves engine system and reactor contractor teams to develop alternative NTP system concepts that can be evaluated against specific attributes, as well as a reference configuration against which to compare system benefits and merits. Quality function deployment (QFD), as an excellent tool within Total Quality Management (TQM) techniques, can provide the required structure and provide a link to the voice of the customer in establishing critical system qualities and their relationships. The third element of the process is the consistent performance comparison. The comparison process involves validating developed concept data and quantifying system merits through analysis, computer modeling, simulation, and rapid prototyping of the proposed high risk NTP subsystems. The maximum amount possible of quantitative data will be developed and/or validated to be utilized in the QFD evaluation matrix. If upon evaluation of a new concept or its associated subsystems determine to have substantial merit, those features will be incorporated into the reference configuration for subsequent system definition and comparison efforts.

  17. AERONET Version 3 processing (United States)

    Holben, B. N.; Slutsker, I.; Giles, D. M.; Eck, T. F.; Smirnov, A.; Sinyuk, A.; Schafer, J.; Rodriguez, J.


    The Aerosol Robotic Network (AERONET) database has evolved in measurement accuracy, data quality products, availability to the scientific community over the course of 21 years with the support of NASA, PHOTONS and all federated partners. This evolution is periodically manifested as a new data version release by carefully reprocessing the entire database with the most current algorithms that fundamentally change the database and ultimately the data products used by the community. The newest processing, Version 3, will be released in 2015 after the entire database is reprocessed and real-time data processing becomes operational. All V 3 algorithms have been developed, individually vetted and represent four main categories: aerosol optical depth (AOD) processing, inversion processing, database management and new products. The primary trigger for release of V 3 lies with cloud screening of the direct sun observations and computation of AOD that will fundamentally change all data available for analysis and all subsequent retrieval products. This presentation will illustrate the innovative approach used for cloud screening and assesses the elements of V3 AOD relative to the current version. We will also present the advances in the inversion product processing with emphasis on the random and systematic uncertainty estimates. This processing will be applied to the new hybrid measurement scenario intended to provide inversion retrievals for all solar zenith angles. We will introduce automatic quality assurance criteria that will allow near real time quality assured aerosol products necessary for real time satellite and model validation and assimilation. Last we will introduce the new management structure that will improve access to the data database. The current version 2 will be supported for at least two years after the initial release of V3 to maintain continuity for on going investigations.

  18. Orchestrator Telemetry Processing Pipeline (United States)

    Powell, Mark; Mittman, David; Joswig, Joseph; Crockett, Thomas; Norris, Jeffrey


    Orchestrator is a software application infrastructure for telemetry monitoring, logging, processing, and distribution. The architecture has been applied to support operations of a variety of planetary rovers. Built in Java with the Eclipse Rich Client Platform, Orchestrator can run on most commonly used operating systems. The pipeline supports configurable parallel processing that can significantly reduce the time needed to process a large volume of data products. Processors in the pipeline implement a simple Java interface and declare their required input from upstream processors. Orchestrator is programmatically constructed by specifying a list of Java processor classes that are initiated at runtime to form the pipeline. Input dependencies are checked at runtime. Fault tolerance can be configured to attempt continuation of processing in the event of an error or failed input dependency if possible, or to abort further processing when an error is detected. This innovation also provides support for Java Message Service broadcasts of telemetry objects to clients and provides a file system and relational database logging of telemetry. Orchestrator supports remote monitoring and control of the pipeline using browser-based JMX controls and provides several integration paths for pre-compiled legacy data processors. At the time of this reporting, the Orchestrator architecture has been used by four NASA customers to build telemetry pipelines to support field operations. Example applications include high-volume stereo image capture and processing, simultaneous data monitoring and logging from multiple vehicles. Example telemetry processors used in field test operations support include vehicle position, attitude, articulation, GPS location, power, and stereo images.

  19. Biomedical Image Processing

    CERN Document Server

    Deserno, Thomas Martin


    In modern medicine, imaging is the most effective tool for diagnostics, treatment planning and therapy. Almost all modalities have went to directly digital acquisition techniques and processing of this image data have become an important option for health care in future. This book is written by a team of internationally recognized experts from all over the world. It provides a brief but complete overview on medical image processing and analysis highlighting recent advances that have been made in academics. Color figures are used extensively to illustrate the methods and help the reader to understand the complex topics.

  20. Exoplanet atmospheres physical processes

    CERN Document Server

    Seager, Sara


    Over the past twenty years, astronomers have identified hundreds of extrasolar planets--planets orbiting stars other than the sun. Recent research in this burgeoning field has made it possible to observe and measure the atmospheres of these exoplanets. This is the first textbook to describe the basic physical processes--including radiative transfer, molecular absorption, and chemical processes--common to all planetary atmospheres, as well as the transit, eclipse, and thermal phase variation observations that are unique to exoplanets. In each chapter, Sara Seager offers a conceptual introdu

  1. Semantic and Process Interoperability

    Directory of Open Access Journals (Sweden)

    Félix Oscar Fernández Peña


    Full Text Available Knowledge management systems support education at different levels of the education. This is very important for the process in which the higher education of Cuba is involved. Structural transformations of teaching are focused on supporting the foundation of the information society in the country. This paper describes technical aspects of the designing of a model for the integration of multiple knowledgemanagement tools supporting teaching. The proposal is based on the definition of an ontology for the explicit formal description of the semantic of motivations of students and teachers in the learning process. Its target is to facilitate knowledge spreading.

  2. Advanced Polymer Processing Facility

    Energy Technology Data Exchange (ETDEWEB)

    Muenchausen, Ross E. [Los Alamos National Laboratory


    Some conclusions of this presentation are: (1) Radiation-assisted nanotechnology applications will continue to grow; (2) The APPF will provide a unique focus for radiolytic processing of nanomaterials in support of DOE-DP, other DOE and advanced manufacturing initiatives; (3) {gamma}, X-ray, e-beam and ion beam processing will increasingly be applied for 'green' manufacturing of nanomaterials and nanocomposites; and (4) Biomedical science and engineering may ultimately be the biggest application area for radiation-assisted nanotechnology development.

  3. Hard exclusive QCD processes

    Energy Technology Data Exchange (ETDEWEB)

    Kugler, W.


    Hard exclusive processes in high energy electron proton scattering offer the opportunity to get access to a new generation of parton distributions, the so-called generalized parton distributions (GPDs). This functions provide more detailed informations about the structure of the nucleon than the usual PDFs obtained from DIS. In this work we present a detailed analysis of exclusive processes, especially of hard exclusive meson production. We investigated the influence of exclusive produced mesons on the semi-inclusive production of mesons at fixed target experiments like HERMES. Further we give a detailed analysis of higher order corrections (NLO) for the exclusive production of mesons in a very broad range of kinematics. (orig.)

  4. An Integrated Desgin Process

    DEFF Research Database (Denmark)

    Petersen, Mads Dines; Knudstrup, Mary-Ann


    Present paper is placed in the discussion about how sustainable measures are integrated in the design process by architectural offices. It presents results from interviews with four leading Danish architectural offices working with sustainable architecture and their experiences with it, as well...... as the requirements they meet in terms of how to approach the design process – especially focused on the early stages like a competition. The interviews focus on their experiences with working in multidisciplinary teams and using digital tools to support their work with sustainable issues. The interviews show...

  5. Research Planning Process (United States)

    Lofton, Rodney


    This presentation describes the process used to collect, review, integrate, and assess research requirements desired to be a part of research and payload activities conducted on the ISS. The presentation provides a description of: where the requirements originate, to whom they are submitted, how they are integrated into a requirements plan, and how that integrated plan is formulated and approved. It is hoped that from completing the review of this presentation, one will get an understanding of the planning process that formulates payload requirements into an integrated plan used for specifying research activities to take place on the ISS.

  6. Multivariate Statistical Process Control

    DEFF Research Database (Denmark)

    Kulahci, Murat


    As sensor and computer technology continues to improve, it becomes a normal occurrence that we confront with high dimensional data sets. As in many areas of industrial statistics, this brings forth various challenges in statistical process control (SPC) and monitoring for which the aim...... is to identify “out-of-control” state of a process using control charts in order to reduce the excessive variation caused by so-called assignable causes. In practice, the most common method of monitoring multivariate data is through a statistic akin to the Hotelling’s T2. For high dimensional data with excessive...

  7. Solar industrial process heat

    Energy Technology Data Exchange (ETDEWEB)

    Lumsdaine, E.


    The aim of the assessment reported is to candidly examine the contribution that solar industrial process heat (SIPH) is realistically able to make in the near and long-term energy futures of the United States. The performance history of government and privately funded SIPH demonstration programs, 15 of which are briefly summarized, and the present status of SIPH technology are discussed. The technical and performance characteristics of solar industrial process heat plants and equipment are reviewed, as well as evaluating how the operating experience of over a dozen SIPH demonstration projects is influencing institutional acceptance and economoc projections. Implications for domestic energy policy and international implications are briefly discussed. (LEW)

  8. Thermal stir welding process (United States)

    Ding, R. Jeffrey (Inventor)


    A welding method is provided for forming a weld joint between first and second elements of a workpiece. The method includes heating the first and second elements to form an interface of material in a plasticized or melted state interface between the elements. The interface material is then allowed to cool to a plasticized state if previously in a melted state. The interface material, while in the plasticized state, is then mixed, for example, using a grinding/extruding process, to remove any dendritic-type weld microstructures introduced into the interface material during the heating process.

  9. Genomic signal processing

    CERN Document Server

    Shmulevich, Ilya


    Genomic signal processing (GSP) can be defined as the analysis, processing, and use of genomic signals to gain biological knowledge, and the translation of that knowledge into systems-based applications that can be used to diagnose and treat genetic diseases. Situated at the crossroads of engineering, biology, mathematics, statistics, and computer science, GSP requires the development of both nonlinear dynamical models that adequately represent genomic regulation, and diagnostic and therapeutic tools based on these models. This book facilitates these developments by providing rigorous mathema

  10. Anaerobic Digestion: Process

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Batstone, Damien J.


    with very little dry matter may also be called a digest. The digest should not be termed compost unless it specifically has been composted in an aerated step. This chapter describes the basic processes of anaerobic digestion. Chapter 9.5 describes the anaerobic treatment technologies, and Chapter 9.......6 addresses the mass balances and environmental aspects of anaerobic digestion....

  11. Authenticizing the Research Process

    Directory of Open Access Journals (Sweden)

    Nora Elizondo-Schmelkes, MA, Ph.D. Candidate


    Full Text Available This study reflects the main concern of students (national and international who are trying to get a postgraduate degree in a third world (or “in means of development” country. The emergent problem found is that students have to finish their thesis or dissertation but they do not really know how to accomplish this goal. They resolve this problem by authenticizing the process as their own. The theory of authenticizing involves compassing their way to solve the problem of advancing in the research process. Compassing allows the student to authenticize his/her research process, making it a personal and „owned. process. The main categories of compassing are the intellectual, physical and emotional dimension patterns that the student has, learns and follows in order to finish the project and get a degree. Authenticizing implies to author with authenticity their thesis or dissertation. Compassing allows them to do this in their own way, at their own pace or time and with their own internal resources, strengths and weaknesses.

  12. Performance Evaluation Process. (United States)


    This document contains four papers from a symposium on the performance evaluation process and human resource development (HRD). "Assessing the Effectiveness of OJT (On the Job Training): A Case Study Approach" (Julie Furst-Bowe, Debra Gates) is a case study of the effectiveness of OJT in one of a high-tech manufacturing company's product…

  13. Advanced Biosignal Processing

    CERN Document Server

    Nait-Ali, Amine


    Presents the principle of many advanced biosignal processing techniques. This title introduces the main biosignal properties and the acquisition techniques. It concerns one of the most intensively used biosignals in the clinical routine, namely the Electrocardiogram, the Elektroenzephalogram, the Electromyogram and the Evoked Potential

  14. Matchmaking for business processes

    NARCIS (Netherlands)

    Wombacher, Andreas; Fankhauser, Peter; Mahleko, Bendick; Neuhold, Erich


    Web services have a potential to enhance B2B ecommerce over the Internet by allowing companies and organizations to publish their business processes on service directories where potential trading partners can find them. This can give rise to new business paradigms based on ad-hoc trading relations a

  15. Flax shive thermocatalytic processing (United States)

    Sulman, E. M.; Lugovoy, Yu. V.; Chalov, K. V.; Kosivtsov, Yu. Yu.; Stepacheva, A. A.; Shimanskaya, E. I.


    In the paper the thermogravimetric study of biomass waste thermodestruction process is presented. Metal chlorides have the highest influence on the flax shive thermodestruction. The results of kinetic modeling are also shown on the base of thermogravimetric analysis both of the samples of flax shive and flax shive with addition of 10% (wt.) nickel chloride at different heating rate.

  16. Ultrahigh bandwidth signal processing (United States)

    Oxenløwe, Leif Katsuo


    Optical time lenses have proven to be very versatile for advanced optical signal processing. Based on a controlled interplay between dispersion and phase-modulation by e.g. four-wave mixing, the processing is phase-preserving, and hence useful for all types of data signals including coherent multi-level modulation formats. This has enabled processing of phase-modulated spectrally efficient data signals, such as orthogonal frequency division multiplexed (OFDM) signals. In that case, a spectral telescope system was used, using two time lenses with different focal lengths (chirp rates), yielding a spectral magnification of the OFDM signal. Utilising such telescopic arrangements, it has become possible to perform a number of interesting functionalities, which will be described in the presentation. This includes conversion from OFDM to Nyquist WDM, compression of WDM channels to a single Nyquist channel and WDM regeneration. These operations require a broad bandwidth nonlinear platform, and novel photonic integrated nonlinear platforms like aluminum gallium arsenide nano-waveguides used for 1.28 Tbaud optical signal processing will be described.

  17. Obsolescence: the underlying processes

    NARCIS (Netherlands)

    Thomsen, A.F.; Nieboer, N.E.T.; Van der Flier, C.L.


    Obsolescence, defined as the process of declining performance of buildings, is a serious threat for the value, the usefulness and the life span of housing properties. Thomsen and van der Flier (2011) developed a model in which obsolescence is categorised on the basis of two distinctions, namely betw

  18. Cascaded Poisson processes (United States)

    Matsuo, Kuniaki; Saleh, Bahaa E. A.; Teich, Malvin Carl


    We investigate the counting statistics for stationary and nonstationary cascaded Poisson processes. A simple equation is obtained for the variance-to-mean ratio in the limit of long counting times. Explicit expressions for the forward-recurrence and inter-event-time probability density functions are also obtained. The results are expected to be of use in a number of areas of physics.

  19. Photonic curvilinear data processing (United States)

    Browning, Clyde; Quaglio, Thomas; Figueiro, Thiago; Pauliac, Sébastien; Belledent, Jérôme; Fay, Aurélien; Bustos, Jessy; Marusic, Jean-Christophe; Schiavone, Patrick


    With more and more photonic data presence in e-beam lithography, the need for efficient and accurate data fracturing is required to meet acceptable manufacturing cycle time. Large photonic based layouts now create high shot count patterns for VSB based tools. Multiple angles, sweeping curves, and non-orthogonal data create a challenge for today's e-beam tools that are more efficient on Manhattan style data. This paper describes techniques developed and used for creating fractured data for VSB based pattern generators. Proximity Effect Correction is also applied during the fracture process, taking into account variable shot sizes to apply for accuracy and design style. Choosing different fracture routines for pattern data on-the-fly allows for fast and efficient processing. Data interpretation is essential for processing curvilinear data as to its size, angle, and complexity. Fracturing complex angled data into "efficient" shot counts is no longer practical as shot creation now requires knowledge of the actual data content as seen in photonic based pattern data. Simulation and physical printing results prove the implementations for accuracy and write times compared to traditional VSB writing strategies on photonic data. Geometry tolerance is used as part of the fracturing algorithm for controlling edge placement accuracy and tuning to different e-beam processing parameters.

  20. The magnetization process: Hysteresis (United States)

    Balsamel, Richard


    The magnetization process, hysteresis (the difference in the path of magnetization for an increasing and decreasing magnetic field), hysteresis loops, and hard magnetic materials are discussed. The fabrication of classroom projects for demonstrating hysteresis and the hysteresis of common magnetic materials is described in detail.

  1. Sustainability of abrasive processes

    DEFF Research Database (Denmark)

    Aurich, J.C.; Linke, B.; Hauschild, Michael Zwicky


    This paper presents an overview of research on sustainability of abrasive processes. It incorporates results from a round robin study on ‘‘energy-efficiency of abrasive processes’’ which has been carried out within the scientific technical committee ‘‘abrasive processes’’ (STC G) of CIRP...


    Directory of Open Access Journals (Sweden)

    Magdalena LUCA (DEDIU


    Full Text Available Business process reengineering determines the change of organizational functions from an orientation focused on operations through a multidimensional approach. Former employees who were mere executors are now determined to take their own decisions and as a result the functional departments lose their reason to exist. Managers do not act anymore as supervisors, but mainly as mentors, while the employees focus more attention on customer needs and less than the head’s. Under these conditions, new organizational paradigms are required, the most important being that of learning organizations. In order to implement a reengineering of the economic processes and promoting a new organizational paradigm the information technology plays a decisive role. The article presents some results obtained in a research theme ANSTI funded by contract no. 501/2000. Economic and financial analysis is performed in order to know the current situation to achieve better results in the future. One of its objectives is the production analyzed as a labour process and the interaction elements of this process. The indicators investigated in the analysis of financial and economic activity of production reflect the development directions, the means and resources to accomplish predetermined objectives and express the results and effectiveness of what is expected.

  3. Attentional Processes in Autism. (United States)

    Goldstein, Gerald; Johnson, Cynthia R.; Minshew, Nancy J.


    Attention processes in 103 children and adults with high functioning autism were compared with a matched control group using a battery of attention measures. Differences were found only on tasks which placed demands on cognitive flexibility or psychomotor speed, suggesting that purported attention deficits in autism may actually be primary…

  4. Normal modified stable processes

    DEFF Research Database (Denmark)

    Barndorff-Nielsen, Ole Eiler; Shephard, N.


    Gaussian (NGIG) laws. The wider framework thus established provides, in particular, for added flexibility in the modelling of the dynamics of financial time series, of importance especially as regards OU based stochastic volatility models for equities. In the special case of the tempered stable OU process...

  5. Communicating Process Achitectures 2005

    NARCIS (Netherlands)

    Broenink, Jan F.; Roebbers, Herman W.; Sunters, Johan P.E.; Welch, Peter H.; Wood, David C.


    The awareness of the ideas characterized by Communicating Processes Architecture and their adoption by industry beyond their traditional base in safety-critical systems and security is growing. The complexity of modern computing systems has become so great that no one person – maybe not even a small

  6. Software Process Improvement

    DEFF Research Database (Denmark)

    Kuhrmann, Marco; Diebold, Philipp; Münch, Jürgen


    Software process improvement (SPI) is around for decades: frameworks are proposed, success factors are studied, and experiences have been reported. However, the sheer mass of concepts, approaches, and standards published over the years overwhelms practitioners as well as researchers. What is out...



    Carrión Muñoz, Rolando; Docente de la FII - UNMSM


    The article shows the role that ergonomics in automation of processes, and the importance for Industrial Engineering.  El artículo nos muestra el papel que tiene la ergonomía en la automatización de los procesos, y la importancia para la Ingeniería Industrial.

  8. Students' Differentiated Translation Processes (United States)

    Bossé, Michael J.; Adu-Gyamfi, Kwaku; Chandler, Kayla


    Understanding how students translate between mathematical representations is of both practical and theoretical importance. This study examined students' processes in their generation of symbolic and graphic representations of given polynomial functions. The purpose was to investigate how students perform these translations. The result of the study…

  9. Restricted broadcast process theory

    NARCIS (Netherlands)

    Ghassemi, F.; Fokkink, W.J.; Movaghar, A.; Cerone, A.; Gruner, S.


    We present a process algebra for modeling and reasoning about Mobile Ad hoc Networks (MANETs) and their protocols. In our algebra we model the essential modeling concepts of ad hoc networks, i.e. local broadcast, connectivity of nodes and connectivity changes. Connectivity and connectivity changes a

  10. Governing Knowledge Processes

    DEFF Research Database (Denmark)

    Foss, Nicolai Juul; Husted, Kenneth; Michailova, Snejina;


    An under-researched issue in work within the `knowledge movement' is therelation between organizational issues and knowledge processes (i.e., sharingand creating knowledge). We argue that managers can shape formalorganization structure and organization forms and can influence the moreinformal...

  11. Audio Spectral Processing (United States)


    Global Security & Engineering Solutions Division 1300-B Floyd Avenue Rome, NY 13440-4615 8. PERFORMING ORGANIZATION REPORT NUMBER...18 1 1. BACKGROUND This report is being submitted by L-3 Global Security...tasks. Utilized the Avid Xpress video enhancement system to process the Group 2, Phase II competency test A. This was done to attempt to recreate

  12. Qualitative Process Theory. (United States)


    write a heat flow process that violates energy conservation and transfers " caloric fluid" between the source and destination. The assumptions made about...removed in ease of ex1-0ClCits. Seco nd, if’ thle program is drawNing concilsions that rely criticaillyoi atClrsum in, then1 it IIos’t test ss

  13. Food processing in action (United States)

    Radio frequency (RF) heating is a commonly used food processing technology that has been applied for drying and baking as well as thawing of frozen foods. Its use in pasteurization, as well as for sterilization and disinfection of foods, is more limited. This column will review various RF heating ap...

  14. Udfordringer for transkulturelle processer

    DEFF Research Database (Denmark)

    Petersen, Karen Bjerg


    at indskrænke mulighedsrummet for transkulturelle processer og for det at lære fra en terra nullius position. Der er fokus på empiriske undersøgelser af kultursyn i lovgivning om opholdstilladelse fra 2010, lovgivning om statsborgerskab fra 2006 samt kultursyn i den i 2003 indførte obligatoriske...

  15. Sparsity and Information Processing


    Ikeda, Shiro


    Recently, many information processing methods utilizing the sparsity of the information source is studied. We have reported some results on this line of research. Here we pick up two results from our own works. One is an image reconstruction method for radio interferometory and the other is a motor command computation method for a two-joint arm.

  16. Image Processing for Teaching. (United States)

    Greenberg, R.; And Others


    The Image Processing for Teaching project provides a powerful medium to excite students about science and mathematics, especially children from minority groups and others whose needs have not been met by traditional teaching. Using professional-quality software on microcomputers, students explore a variety of scientific data sets, including…

  17. Image-Processing Program (United States)

    Roth, D. J.; Hull, D. R.


    IMAGEP manipulates digital image data to effect various processing, analysis, and enhancement functions. It is keyboard-driven program organized into nine subroutines. Within subroutines are sub-subroutines also selected via keyboard. Algorithm has possible scientific, industrial, and biomedical applications in study of flows in materials, analysis of steels and ores, and pathology, respectively.

  18. The Serendipitous Research Process (United States)

    Nutefall, Jennifer E.; Ryder, Phyllis Mentzell


    This article presents the results of an exploratory study asking faculty in the first-year writing program and instruction librarians about their research process focusing on results specifically related to serendipity. Steps to prepare for serendipity are highlighted as well as a model for incorporating serendipity into a first-year writing…

  19. Automated process planning system (United States)

    Mann, W.


    Program helps process engineers set up manufacturing plans for machined parts. System allows one to develop and store library of similar parts characteristics, as related to particular facility. Information is then used in interactive system to help develop manufacturing plans that meet required standards.

  20. Quantum image processing? (United States)

    Mastriani, Mario


    This paper presents a number of problems concerning the practical (real) implementation of the techniques known as quantum image processing. The most serious problem is the recovery of the outcomes after the quantum measurement, which will be demonstrated in this work that is equivalent to a noise measurement, and it is not considered in the literature on the subject. It is noteworthy that this is due to several factors: (1) a classical algorithm that uses Dirac's notation and then it is coded in MATLAB does not constitute a quantum algorithm, (2) the literature emphasizes the internal representation of the image but says nothing about the classical-to-quantum and quantum-to-classical interfaces and how these are affected by decoherence, (3) the literature does not mention how to implement in a practical way (at the laboratory) these proposals internal representations, (4) given that quantum image processing works with generic qubits, this requires measurements in all axes of the Bloch sphere, logically, and (5) among others. In return, the technique known as quantum Boolean image processing is mentioned, which works with computational basis states (CBS), exclusively. This methodology allows us to avoid the problem of quantum measurement, which alters the results of the measured except in the case of CBS. Said so far is extended to quantum algorithms outside image processing too.