Search results for " Laboratory"
showing 10 items of 622 documents
Semiautomatic growth analysis of multicellular tumor spheroids.
2011
Multicellular tumor spheroids (MCTS) are routinely employed as three-dimensional in vitro models to study tumor biology. Cultivation of MCTS in spinner flasks provides better growing conditions, especially with regard to the availability of nutrients and oxygen, when compared with microtiter plates. The main endpoint of drug response experiments is spheroid size. It is common practice to analyze spheroid size manually with a microscope and an ocular micrometer. This requires removal of some spheroids from the flask, which entails major limitations such as loss of MCTS and the risk of contamination. With this new approach, the authors present an efficient and highly reproducible method to an…
Tick-borne pathogens in Ixodes ricinus ticks collected from migratory birds in southern Norway
2020
Birds are important hosts for the first life stages of the Ixodes ricinus tick and they can transport their parasites over long distances. The aim of this study was to investigate the prevalence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Neoehrlichia mikurensis and Rickettsia helvetica in ticks collected from migratory birds in Norway. A total of 815 Ixodes ricinus ticks from 216 birds trapped at Lista Bird Observatory in southern Norway during spring and autumn migration in 2008 were analysed by real-time PCR. B. burgdorferi s. l. was the most prevalent pathogen, detected in 6.1% of the ticks. The prevalence of N. mikurensis, A. phagocytophilum and R. helvetica was 1.2%…
Culture and Real-time Polymerase Chain reaction sensitivity in the diagnosis of invasive meningococcal disease: Does culture miss less severe cases?
2019
BackgroundInvasive meningococcal disease (IMD) is a highly lethal disease. Diagnosis is commonly performed by culture or Realtime-PCR (qPCR).AimsOur aim was to evaluate, retrospectively, whether culture positivity correlates with higher bacterial load and fatal outcome. Our secondary aim was to compare culture and qPCR sensitivity.MethodsThe National Register for Molecular Surveillance was used as data source. Cycle threshold (CT), known to be inversely correlated with bacterial load, was used to compare bacterial load in different samples.ResultsThree-hundred-thirteen patients were found positive for Neisseria meningitidis by qPCR, or culture, or both; 41 died (case fatality rate 13.1%); 1…
Stimulated and unstimulated saliva samples have significantly different bacterial profiles
2018
Epidemiological studies use saliva on a regular basis as a non-invasive and easy-to-take sample, which is assumed to be a microbial representative of the oral cavity ecosystem. However, comparative studies between different kinds of saliva samples normally used in microbial studies are scarce. The aim of the current study was to compare oral microbiota composition between two different saliva samples collected simultaneously: non-stimulated saliva with paper points and stimulated saliva collected after chewing paraffin gum. DNA was extracted from saliva samples of ten individuals, then analyzed by 16S rRNA pyrosequencing to describe bacterial diversity. The results demonstrate significant d…
Re: The Clinical Impact of Bacteremia on Outcomes in Elderly Patients with Pyelonephritis or Urinary Sepsis: A Prospective Multicenter Study
2018
Background Bacteremia is common in severe urinary infections, but its influence on the outcomes is not well established. The aim of this study was to assess the association of bacteremia with outcomes in elderly patients admitted to hospital with pyelonephritis or urinary sepsis. Methods This prospective muticenter observational study was conducted at 5 Spanish hospitals. All patients aged >65 years with pyelonephritis or urinary sepsis admitted to the departments of internal medicine and with urine and blood cultures obtained at admission to hospital were eligible. Transfer to ICU, length of hospital stay, hospital mortality and all cause 30-day mortality in bacteremic and non-bacteremic g…
Performance of QuantiFERON-TB Gold Plus for detection of latent tuberculosis infection in pregnant women living in a tuberculosis- and HIV-endemic se…
2017
We evaluated the performance of QuantiFERON-TB Gold Plus (QFT-Plus), which includes two Mycobacterium tuberculosis antigen formulations (TB1 and TB2), for detection of latent tuberculosis infection during pregnancy. Eight-hundred-twenty-nine Ethiopian pregnant women (5.9% HIV-positive) were tested with QFT-Plus, with bacteriological sputum analysis performed for women with clinically suspected tuberculosis and HIV-positive women irrespective of clinical presentation. QFT-Plus read-out was categorized according to the conventional cut-off (0.35 IU/ml) for both antigen formulations. In addition, we analysed the distribution of QFT-Plus results within a borderline zone (0.20–0.70 IU/ml), and i…
Importance of Propionibacterium acnes hemolytic activity in human intervertebral discs: A microbiological study
2018
Most patients with chronic lower back pain (CLBP) exhibit degenerative disc disease. Disc specimens obtained during initial therapeutic discectomies are often infected/colonized with Propionibacterium acnes, a Gram-positive commensal of the human skin. Although pain associated with infection is typically ascribed to the body's inflammatory response, the Gram-positive bacterium Staphylococcus aureus was recently observed to directly activate nociceptors by secreting pore-forming α-hemolysins that disrupt neuronal cell membranes. The hemolytic activity of P. acnes in cultured disc specimens obtained during routine therapeutic discectomies was assessed through incubation on sheep-blood agar. T…
Experimental observations of upstream overdeepening
2005
The issue of morphodynamic influence in meandering streams is investigated through a series of laboratory experiments on curved and straight flumes. Both qualitative and quantitative observations confirm the suitability of the recent theoretical developments (Zolezzi & Seminara 2001) that indicate the occurrence of two distinct regimes of morphodynamic influence, depending on the value of the width ratio of the channel β. The threshold value βR separating the upstream from the downstream influence regimes coincides with the resonant value discovered by Blondeaux & Seminara (1985). Indeed it is observed that upstream influence may occur only in relatively wide channels, while narrower stream…
Evaluation of the laboratory prediction of surface properties of bituminous mixtures. Construction and Building Materials. Volume 23. Issue 2. Elsevi…
2009
An experimental and analytical investigation was carried out both in laboratory and in situ on wearing courses. The approach presented in this paper aims to predict the in situ density and surface properties of bituminous layers, during the phase of mix design in laboratory. Therefore, the main attempt of this study is to identify, amongst the commonly available laboratory equipments, the most adequate for producing specimens that, used for carrying out simple and reliable laboratory test, allow the prediction of the surface characteristics of the mixture as laid on site. This is done by comparing the data collected from an experimental site with those calculated from laboratory specimens c…
A Worldwide Perspective on COVID-19 and Diabetes Management in 22,820 Children from the SWEET Project: Diabetic Ketoacidosis Rates Increase and Glyce…
2021
Aims: To investigate the short-term effects of the first wave of COVID-19 on clinical parameters in children with type 1 diabetes (T1D) from 82 worldwide centers participating in the Better Control in Pediatric and Adolescent DiabeteS: Working to CrEate CEnTers of Reference (SWEET) registry. Materials and Methods: Aggregated data per person with T1D £21 years of age were compared between May/June 2020 (first wave), August/September 2020 (after wave), and the same periods in 2019. Hierarchic linear and logistic regression models were applied. Models were adjusted for gender, age-, and diabetes duration-groups. To distinguish the added burden of the COVID-19 pandemic, the centers were divided…