176 research outputs found
Rapid microbiological diagnosis of infections in sterile body fluids including blood
Infections of normally sterile body fluids (SBF) including blood, cerebrospinal-, pleural-, peritoneal, – pericardial and synovial fluid are critical and require early diagnosis and rapid initiation of appropriate antimicrobial therapy. With the advanced and invasive care of modern medicine, infections of SBF are increasing worldwide. The clinical microbiology laboratory is crucial in facilitating targeted therapy through early microorganism detection, identification and antibiotic susceptibility testing. This actionable information will allow correct antimicrobial therapy early in the infectious process.
Blood culture systems as well as blood culture bottles are the standard diagnostic method in blood cultures and are utilized for SBF cultures. The overall aim of this thesis was to evaluate and improve the microbiological diagnosis of SBF including blood from positive blood culture bottles.
The first study focused on BacT/Alert Virtuo blood culture system introduced into the market to replace the BacT/Alert 3D blood culture system by the same company. The study presented in this thesis showed a significantly shorter time to detection for bottles incubated in the Virtuo system than those incubated in the BacT/Alert 3D system (median 12 h and 15 h, respectively; p < 0.0001) in simulated blood cultures.
In Study 2, the performance a unique method of short-term culture followed by MALDI-TOF
MS was analyzed prospectively. The study showed a successful identification of 424/515 (82.3%) bacteria with MALDI-TOF MS after 5.5 h subculture on solid media.
In Study 3 and 4, the FilmArray BCID panel was prospectively evaluated for accurate identification and limited antibiotic susceptibility testing. In Study 3, the FilmArray BCID showed accurate identification of microorganisms in 153/167 (91.6%) and 17/24 (71%) culture positive blood culture bottles with monomicrobial- and polymicrobial-growth. In Study 4, the performance of FilmArray BCID was analyzed for SBF other than blood. The assay could identify all microorganisms in 84/84 (100%) and 18/24 (75%) SBF samples with mono- and polymicrobial growth respectively. These studies showed that the FilmArray BCID panel is a reliable and fast method that may be utilized in blood cultures as well as other SBF that are cultured in blood culture bottles.
In Study 5, the performance of four S. pneumoniae antigen tests including ImmuLexTM, SlideX® pneumo-Kit, WellcogenTM, and BinaxNOW® were evaluated. The study revealed similar sensitivity of 99.6%-100% for all tests when excluding invalid results in the calculation. However, the study showed that the BinaxNow® had the lowest specificity (64.1% 9, p<0.01) among the four methods. The ImmuLexTM test had lower specificity than the Slidex® test (82.6% vs 97.6%, p<0.01) and performed similar to the WellcogenTM test (84.5%, p=ns).
In conclusion, the present thesis showed that the new Virtuo blood culture system allows faster detection of microorganisms in blood culture bottles. The thesis further presented several methods for rapid identification of microorganisms after detection of growth in blood culture bottles. These tests included FilmArray BCID panel and the latex agglutination tests directly from blood culture bottles while MALDI-TOF MS was performed after sub-culture on solid media. These rapid tests are important complements to the rigorous and extensive conventional culture methods and provide early critical actionable information for appropriate antimicrobial stewardship
Alev sprey yöntemiyle etilen-vinil-asetat kaplamaların üretilmesi ve karakterizasyonu
06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Anahtar Kelimeler: Alev Sprey Yöntemi, Polimer/plastik Kaplama, KorozyonGelişmekte olan ülkemizde, korozyon ve aşınma kayıpları net bir şekilde belirlenmemiş olmakla birlikte ekonomimize büyük kayıplar vermektedir. Günümüzde malzemelerin kullanım ömrünü sınırlayan aşınma ve korozyon etkilerinin giderilmesine yönelik olarak birçok yüzey işlemi ve kaplama teknolojisi kullanılmaktadır. Korozyon kayıpları astar boya (antipas) ve değişik kaplamalar ile önlenmeye çalışılmaktadır. Bu uygulamalar çok bilinmekte olup bir çok alanda başarılı olarak uygulanmaktadır.Sunulan tez kapsamında, alev sprey yöntemi ile boyaya alternatif olarak sunulan polimer/plastik ( EVA-etilen vinil asetat) püskürtme uygulamaları yapılmıştır. EVA kaplamalarının püskürtme yoluyla üretilmesi modifiye bir tabanca kullanımıyla gerçekleştirilmiştir. Bu kapsamda öncelikli olarak cihaz kullanımıyla ilgili gerekli optimum üretim parametreleri yapısal karakterizasyon yöntemleriyle belirlenmiş ve daha sonra bu parametreler kullanılarak üretilen kaplama numunelerine tuz püskürtme korozyon testi uygulanmıştır. Bunun yanı sıra üretilen bu kaplamaların UV yaşlandırma özellikleri ile, mazot, benzin, motor yağı ve saf alkol içerisindeki kullanım ömrü araştırılmıştır. Son olarak EVA polimer tozuna SiC, Al2O3, TiO2 ve soda-kireç camı ilaveleri yapılarak üretilen kaplamaların aşınma performansı araştırılmıştır.Keywords: Flame Spray Process, Plastics/Polymers, CorrosionIn our developing country, corrosion and wear loses, which are not still determined economically, has big disadvantes to our economy. In todays, there are many surface treatments and coating techologies which are used to overcome wear and corrosion disadvantages that limit directly materials service life. Wear loses could be overcame by primarily welding aplication and corrosion loses could be overcame by applying undercoat onto material which is desired protecting from corrosion. These applications are well known application and are used succesfully in many area.In this thesis, the polymer / flame spray plastic coating spray, being an alternative application for paint, applications carried out. Production of EVA coatings carried out by using a modified spraying gun. In this case, leading purpose is to achieve the optimum parameters for prime usage of the spraying system by considering structural characterization methods. Formerly the coating samples, produced with usage of optimum parameters established before, subjected to salt spray corrosion test, gasoline, diesel, engine oil and alcohol as well as UV ageing. Lastly, SiC, Al2O3, TiO2 and plain glass aded into EVA polymer powder and produced coatings using these mixed powders. The composite coatings wear performance was also studied
Koroner arter girişimi sırasında ani tıkanma: Bu kabus kontrast maddeyle ilişkili mi?
Kırk altı yaşında, koroner arter hastalığı için risk faktörü olarak hipertansiyon ve aile öyküsü olan erkek hasta akut anterior miyokard infarktüsünün ikinci saati içinde kliniğimize başvurdu. Kurtarıcı perkütan koroner girişim sırasında sol ön inen arterin tam tıkandığı gözlendi. İşlem sırasında kullanılan 150 ml non-iyonik, düşük osmolar kontrast maddenin trombüse yol açarak tam tıkanıklığa neden olabileceği düşünüldü. İntrakoroner bolus tirofiban infüzyonu sonrasında intrakoroner trombozun çözüldüğü görüldü. Lezyon bölgesine stent uygulandı ve TIMI III akımla birlikte çok iyi anjiyografik sonuç elde edildi. Beş ay sonra yapılan kontrol anjiyografide sol ön inen koroner arter tamamen açık idi. Kurtarıcı işlem sırasında gelişen akut koroner tıkanmaların tedavisinde tirofiban infüzyonuyla bareber stentleme tıkanıklığı etkin bir şekilde gidermektedir.A 46-year-old man with hypertension and family history for coronary artery disease presented to our department within the second hour of acute anterior wall myocardial infarction. During rescue percutaneous transluminal coronary angioplasty, total occlusion occured in the left anterior descending (LAD) coronary artery. A total of 150 ml of non-ionic, low-osmolar contrast agent was used and it was thought that non-ionic contrast media could have induced thrombus formation. After bolus intracoronary tirofiban administration, there was satisfactory resolution of the intracoronary thrombosis. Stent implantation at the lesion site resulted in an excellent angiographic result with a TIMI III flow. At five-month control angiography, the LAD was widely patent. Acute total occlusions during rescue coronary angioplasty can be effectively managed by tirofiban infusion and stenting
Improved chemotaxis differential evolution optimization algorithm
The social foraging behavior of Escherichia coli has recently received great attention and it has been employed to solve complex search optimization problems.This paper presents a modified bacterial foraging optimization BFO algorithm, ICDEOA (Improved Chemotaxis Differential Evolution Optimization Algorithm), to cope with premature convergence of reproduction operator.In ICDEOA, reproduction operator of BFOA is replaced with probabilistic reposition operator to enhance the intensification and the diversification of the search space.ICDEOA was compared with state-of-the-art DE and non-DE variants on 7 numerical functions of the 2014 Congress on Evolutionary Computation (CEC 2014). Simulation results
of CEC 2014 benchmark functions reveal that ICDEOA performs better than that of competitors in terms of the quality of the final solution for high dimensional problems
Identification of dynamic loads on structural component with artificial neural networks
Enhancing structural components by implementing sensors offers great potential regarding condition monitoring for lifetime analysis, predictive maintenance and automatic adaptation to environmental conditions. This article describes an approach to determining the operational forces applied to the front suspension arm of a car using strain gauges. Since suspension arms are components with free-form surfaces, an analytical calculation of applied forces by means of measured strains is not feasible. Hence, artificial neural networks are applied to approximate the functional relationship. The results reveal how artificial neural networks can be applied to identify load conditions on structural components and, therefore, deliver essential data for condition monitoring
Enhanced findability and reusability of Engineering Data by Contextual Metadata
Complex research problems are increasingly addressed by interdisciplinary, collaborate research projects generating large amounts of heterogeneous amounts of data. The overarching processing, analysis and availability of data are critical success factors for these research efforts. Data repositories enable long term availability of such data for the scientific community. The findability and therefore reusability strongly builds on comprehensive annotations of datasets stored in repositories. Often generic metadata schema are used to annotate data. In this publication we describe the implementation of discipline specific metadata into a data repository to provide more contextual information about data. To avoid extra workload for researchers to provide such metadata a workflow with standardised data templates for automated metadata extraction during the ingest process has been developed. The enriched metadata are in the following used in the development of two repository plugins for data comparison and data visualisation. The added values of discipline-specific annotations and derived search features to support matching and reusable data is then demonstrated by use cases of two Collaborative Research Centres (CRC 1368 and CRC 1153)
The Effects of Topical Antiglaucoma Drugs as Monotherapy on the Ocular Surface: A Prospective Study
Purpose. The aim was to compare the effects of antiglaucoma eye drops on the tear functions and ocular surface. Method. Eighty-five eyes of 43 patients with glaucoma were included into this randomized prospective study. Timolol without preservative (1), timolol with benzododecinium bromide (2), latanoprost (3), bimatoprost (4), travoprost with benzalkonium chloride (5), and brimonidine with purite (6) were given to 6 groups. Schirmer I, tear film breakup time (TBUT), staining scores, and impression cytology samples were evaluated before and during 12-month-follow-up period. Results. At the end of 12 months, there was no detected change in Schirmer I and TBUT tests indicating dry eye. Corneal staining scores were higher in groups 1 and 2, while conjunctival staining scores were higher in group 6. Goblet cell count decreased in groups 1 and 5 in superior and inferior, group 2 in superior, and groups 3 and 6 in inferior conjunctiva. Squamous metaplasia grades showed a significant increase in groups 1 and 2 at 3rd, 6th, and 12th month controls (P<0.05). Conclusion. We observed nonserious impact on tear functions and ocular surface with antiglaucoma monotherapy. Beta blockers induced more damage on the ocular surface suggesting the role of the dosing and active substances beside preservatives
Effect of Korean Red Ginseng on Noise-Induced Hearing Loss
Objective:Noise-induced hearing loss (NIHL) is one of the most important problems affecting both social and professional life of patients. There is no treatment method considered to be successful on the hearing loss that has become a permanent nature. Aim of this study is to evaluate protective effect of Korean Red Ginseng (KRG) against NIHL in an animal model.Methods:Twenty-eight rats were separated into four groups [control saline (group I), control KRG (group II), saline + noise (group III), KRG + noise (group IV)]. Rats in the saline and KRG groups were fed via oral gavage with a dose of 200 mg/kg/day throughout for 10 days. Fourteen rats (group III and IV) were exposed to 4 kHz octave band noise at 120 dB SPL for 5 hours. Hearing levels of rats were evaluated by distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) at 4, 8, 12, 16 and 32 kHz frequencies prior to and on days 1, 7 and 10 after the noise exposure. Rats were sacrificed on 10th day, after the last audiological test. Cochlea and spiral ganglion tissues were evaluated by light microscopy.Results:Audiological and histological results demonstrated that after noise the group IV showed better results than group III. In the noise exposed groups, the most prominent damage was seen at the 8 kHz frequency region than other regions. After the noise exposure, DPOAE responses were lost in 1st, 7th and 10th measurements in both group III and IV. Thus, we were not able to perform any statistical analyses for DPOAE results.Conclusion:Our findings suggest that KRG seems to be an efficient agent against NIHL. There is need for additional research to find out about the mechanisms of KRG’s protective effect
EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial
More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369
Diagnosis of comorbid migraine without aura in patients with idiopathic/genetic epilepsy based on the gray zone approach to the International Classification of Headache Disorders 3 criteria
BackgroundMigraine without aura (MwoA) is a very frequent and remarkable comorbidity in patients with idiopathic/genetic epilepsy (I/GE). Frequently in clinical practice, diagnosis of MwoA may be challenging despite the guidance of current diagnostic criteria of the International Classification of Headache Disorders 3 (ICHD-3). In this study, we aimed to disclose the diagnostic gaps in the diagnosis of comorbid MwoA, using a zone concept, in patients with I/GEs with headaches who were diagnosed by an experienced headache expert.MethodsIn this multicenter study including 809 consecutive patients with a diagnosis of I/GE with or without headache, 163 patients who were diagnosed by an experienced headache expert as having a comorbid MwoA were reevaluated. Eligible patients were divided into three subgroups, namely, full diagnosis, zone I, and zone II according to their status of fulfilling the ICHD-3 criteria. A Classification and Regression Tree (CART) analysis was performed to bring out the meaningful predictors when evaluating patients with I/GEs for MwoA comorbidity, using the variables that were significant in the univariate analysis.ResultsLonger headache duration (<4 h) followed by throbbing pain, higher visual analog scale (VAS) scores, increase of pain by physical activity, nausea/vomiting, and photophobia and/or phonophobia are the main distinguishing clinical characteristics of comorbid MwoA in patients with I/GE, for being classified in the full diagnosis group. Despite being not a part of the main ICHD-3 criteria, the presence of associated symptoms mainly osmophobia and also vertigo/dizziness had the distinguishing capability of being classified into zone subgroups. The most common epilepsy syndromes fulfilling full diagnosis criteria (n = 62) in the CART analysis were 48.39% Juvenile myoclonic epilepsy followed by 25.81% epilepsy with generalized tonic-clonic seizures alone.ConclusionLonger headache duration, throbbing pain, increase of pain by physical activity, photophobia and/or phonophobia, presence of vertigo/dizziness, osmophobia, and higher VAS scores are the main supportive associated factors when applying the ICHD-3 criteria for the comorbid MwoA diagnosis in patients with I/GEs. Evaluating these characteristics could be helpful to close the diagnostic gaps in everyday clinical practice and fasten the diagnostic process of comorbid MwoA in patients with I/GEs
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