Design, Performance and Calibration of the CMS Forward Calorimeter Wedges

We report on the test beam results and calibration methods using charged particles of the CMS Forward Calorimeter (HF). The HF calorimeter covers a large pseudorapidity region (3\l |\eta| \le 5), and is essential for large number of physics channels with missing transverse energy. It is also expected to play a prominent role in the measurement of forward tagging jets in weak boson fusion channels. The HF calorimeter is based on steel absorber with embedded fused-silica-core optical fibers where Cherenkov radiation forms the basis of signal generation. Thus, the detector is essentially sensitive only to the electromagnetic shower core and is highly non-compensating (e/h \approx 5). This feature is also manifest in narrow and relatively short showers compared to similar calorimeters based on ionization. The choice of fused-silica optical fibers as active material is dictated by its exceptional radiation hardness. The electromagnetic energy resolution is dominated by photoelectron statistics and can be expressed in the customary form as a/\sqrt{E} + b. The stochastic term a is 198% and the constant term b is 9%. The hadronic energy resolution is largely determined by the fluctuations in the neutral pion production in showers, and when it is expressed as in the electromagnetic case, a = 280% and b = 11%

Comparison of minimal inhibitory concentrations (MICs) of tigecycline in 2011 and 2015 years against multidrug-resistance acinetobacter baumannii strains

Acinetobacter baumannii is an opportunistic pathogen that causing nosocomial infections. The microorganisms can be developed resistance to antimicrobials very quickly by different mechanisms. Infections defend by MDR strains, caused require long-term hospitalization high morbidity and mortality. Tigecycline is one of the few antimicrobials which have activity against MDR A. baumannii strains. In Meta-analyzes and clinical study reported that a rising risk of mortality in tigecycline-treated patients due to an increase in resistance of these strains. In our study, we aimed to compare the MICs values of tigecycline and determine the resistance rates of tigecycline against to MDR A. baumannii strains in 2011 and 2015. Tigecycline MIC values of 200 A. baumannii isolates were determined by the broth microdilution method. Final concentrations were prepared as 16μg/ml to 0.06μg/ml. Tigecycline MICs breakpoint values comments on breakpoint values of Enterobacteriaceae that have been proposed by FDA. In 2011, tigecycline values of MIC50 and MIC 90 found 0.5μg/ml, 1μg/ml, respectively against to MDR A. baumannii strains. In 2015, tigecycline values of MIC50 and MIC90 found 1μg/ml, 4μg/ml, respectively. In 2011 the 4%, while in 2015, 16% of A. baumannii strains tigecycline MICs were determined over 2μg/ml. and that this was interpreted as the resistance. Tigecycline can be still use as an alternative antimicrobial for treatment of A. baumannii strains, especially in our hospitals intensive care units. However, to avoid the development of resistance against tigecycline, we should prevent the irrational use of antibiotics. The implementation of treatment should be based on antimicrobial susceptibility test results. [Med-Science 2017; 6(1.000): 26-9

Changing trends of carbapenem resistance of escherichia coli and klebsiella pneumoniae strains isolated from intensive care units, inpatient services and outpatients clinics: a five years retrospective analysis

Background: Carbapenem resistance (CR) was rarely reported in Klebsiella pneumoniae and Escherichia coli strains until ten years ago. In recent years, increasing carbapenem resistance in gram negative bacteria is a substantial concern. Objectives: In this study; we aimed to evaluate the changing frequency of CR in K.pneumoniae and E.coli strains that were isolated from the patients from intensive care units, inpatient services and outpatients clinics in the last five years. Methods: Data of antimicrobial susceptibility belonging to clinical isolates of K.pneumoniae and E.coli strains determined between 2013 and 2017 were retrospectively collected from Laboratory Information System. Results were statistically analyzed. Results: A total 4002 K.pneumoniae and 13462 E.coli strains were included. The CR of K.pneumoniae strains were found as 11.6%; while of E.colis were found as 0.6%. The highest CR frequency was detected among intensive care units isolates of K. pneumoniae as 20.1%. We determined that CR significantly increased in intensive care unit isolates of E.coli and K.pneumoniae about 5-10 folds throughout the study period; however, there was no remarkable change in the CR of E.coli strains from the outpatients clinics. Conclusion: We determined that the resistances of K.pneumoniae and E.coli strains to carbapenems were progressively increasing by years, especially in intensive care units and inpatient services. Therefore, appropriate antimicrobial use policies sought to be considered against to this growing problem. [Med-Science 2018; 7(3.000): 536-9

Is airborne transmission of Acinetobacter baumannii possible: A prospective molecular epidemiologic study in a tertiary care hospital

BAYINDIR, Yasar/0000-0003-3930-774X; Otlu, Baris/0000-0002-6220-0521; Ersoy, Yasemin/0000-0001-5730-6682WOS: 000392626300032PubMed: 27561435Background: Understanding the dynamics of aerial spread of Acinetobacter may provide useful information for production of effective control measurements. We investigated genetic relationships between air and clinical isolates of Acinetobacter baumannii in an intensive care unit (ICU) setting. Methods: We conducted a prospective surveillance study in a tertiary care hospital for 8 months. A total of 186 air samples were taken from 2 ICUs. Clonal characteristics of air isolates were compared with the prospective clinical strains and the previously isolated strains of ICU patients over a 23-month period. Results: Twenty-six (11.4%) air samples yielded A baumannii, of which 24 (92.3%) isolateswere carbapenemresistant. the Acinetobacter concentrationwas the highest in bedside sampling areas of infected patients (0.39 CFU/m(3)). Air isolateswere clustered in 13 genotypes, and 7 genotypes (including 18 air strains) were clonally related to the clinical strains of 9 ICU patients. One clone continued to be cultured over 27 days in ICU air, and air isolates could be clonally related to 7-week retrospective and approximately 15-week prospective clinical strains. Conclusions: the results of this study suggest that infected patients could spread significant amounts of Acinetobacter to ICU air. These strains could survive in air for some weeks and could likely still infect new patients after some months. Special control measurements may be required against the airborne spread of Acinetobacter in ICUs. (C) 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved

The Identification of Acinetobacter baumannii Blood Isolates by MALDI-TOF MS, ARDRA and bla(OXA-51-like) Gene-Specific Real-Time PCR

The Acinetobacter cakoaceticus-Acinetobacter baumannii (Acb) complex consists of phenotypically very similar nosocomial species; A.baumannii, Acinetobacter nosocomialis, Acinetobacter pittii, Acinetobacter seifertii and Acinetobacter djikshoorniae and one environmental species Acakoaceticus. The rapid and accurate identification of the members of Acb complex is critical as these nosocomial pathogens can show differences in antimicrobial susceptibility and clinical outcomes. The conventional phenotypic methods are slow, unreliable and less efficient for the differentiation of Acb complex species, including the A.baumannii species within the Acb complex. Although various molecular methods are available, such as amplified ribosomal DNA restriction analysis (ARDRA) and bla(OXA-51-like), gene specific PCR, they are usually inconvenient for the routine diagnostic laboratories. Recently, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) offers an opportunity for rapid, cost-effective and convenient bacterial identification in routine diagnostic procedures conducted in clinical laboratory. In this study, we aimed to evaluate the diagnosis performance of MALDI-TOF MS system to identify blood isolates of A.baumannii. A total of 180 nonduplicate carbapenem resistant Acb complex (strain numbers; TR1-TR60) and A.baumannii (TR61-TR180) blood isolates were collected from the intensive care units of the three university hospitals in Turkey from January 2016 to December 2016. All isolates were evaluated by using bla(OXA-51-like) gene specific real time (Rt-PCR) analysis, ARDRA (restriction enzymes-AIM, Cfol, Mbol, Mspl, Rsal) method and MALDI-TOF MS (VITEK (R) MS, bioMerieux, France) system. All the strains except TRIO, TR31, TR35 and TR52 were identified as A.baumannii by ARDRA method. Out of 177 of all the isolates, presence of bla(OXA-51-like) gene was found except for TR10, TR31 and TR52 isolates. However, TR31 without the presence of bla(OXA-51-like) gene was identified as A.pittii using the ARDRA. Totally 176 isolates which were identified as A. baumannii by both of the methods, ARDRA and Rt-PCR-bla(OXA-51-like) ,were accepted as a reference for the evaluation of the diagnosis performance capacity of the MALDI-TOF MS. Overall, for all 176 isolates tested, the sensitivity obtained with the MALDI-TOF MS were 99.4% with 75% specificity. The accuracy value of the method was determined as 98.9% for the identification of A.baumannii to the species level. MALDI-TOF MS is increasingly used in diagnostic microbiology for the routine identification of bacteria to the genus, species or subspecies level with high rates of sensitivity and specificity. In future, by expanding the database, MALDI-TOF MS system would possibly become the ideal method for routine diagnostic laboratories that could potentially identify more species and even determine some characteristics of antimicrobial resistance and virulence determinants

Molecular Characterization of Carbapenem-Resistant Acinetobacter baumannii Blood Culture Isolates from Three Hospitals in Turkey

We aimed to investigate the clonal relationships, common sequence types, and carbapenemase genes in 177 non-repetitive blood culture isolates of Acinetobacter baumannii collected from patients at three university hospitals in Turkey in 2016. Molecular epidemiological characteristics of the isolates were examined using pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing (MLST) (Pasteur scheme-cpn60, fusA, gltA, pyrG, recA, rplB, and rpoB). Multiplex PCR was used to investigate the carbapenemase genes, including bla(OXA-23-like),bla(OXA-24-like), bla(OXA-48-like), bla(OXA-58-like), bla(IMP), bla(VIM) and bla(NDm). PFGE genotyping yielded 92 pulsotypes with a clustering ratio of 69.7%. As per a >= 85% similarity coefficient, 159 (90.9%) isolates were found to be clonally related. The bla(OXA-)(23-like) and bla(OXA-)(58)-like genes were identified in 100% and 28.2% of the isolates, respectively. The bla(NDM) gene was identified in two isolates. The MLST analysis included 54 isolates with different pulsotypes, and 29 sequence types (STs). Most of the isolates (n = 36) belonged to the clonal complex (CC)2, one isolate belonged to CC1, and one isolate belonged to CC164. Sixteen new STs (ST1235-ST1250) were identified. Identifying both global ST2 and a large number of new STs, revealed high genetic diversity in A. baumannii isolates in the study population

Pseudo-outbreak of stenotrophomonas maltophilia isolated from kidney stones and attributed to inadequate sterilization: Investigation of molecular typing and clonal relationship

Stenotrophomonas maltophilia is a gram-negative bacterium. Hospitals can be a source of S. maltophilia because it adheres to nonliving surfaces and forms a biofilm. This study was performed to investigate the clonal relationship between S. maltophilia isolates obtained from kidney stone samples. Samples of kidney stones taken from patients and surrogate samples from nephroscopes, cleaning solution, disinfectant solution were included in the study. The clonal relationship between isolates was determined by PFGE. S. maltophilia was isolated from 34 of 94 kidney stone samples sent from the urology operating room between July 2017 and January 2018. A total of 26 S. maltophilia strains (21 from kidney stone samples, three from nephroscopes, and two from urine culture) were isolated. PFGE showed that the 21 kidney stone isolates and the 3 S. maltophilia isolates obtained from the nephroscope belonged to the same clone. The two urine culture isolates showed no clonal relationship to the outbreak isolates and were considered sporadic. Molecular typing confirmed that this pseudo-outbreak was attributed to inadequate disinfection of the nephroscopes. After disinfection protocols were reviewed and revised as needed, especially regarding the removal of organic material from nephroscopes after use, no further bacterial growth was detected from kidney stone specimens obtained with nephroscopes. [Med-Science 2020; 9(3.000): 589-94