Kinetics of antibody response to Coxiella burnetii infection (Q fever): Estimation of the seroresponse onset from antibody levels

AbstractBackgroundFrom 2007 to 2009, the Netherlands experienced a major Q fever epidemic. Long-term serological follow-up of acute Q fever patients enabled the investigation of longitudinal antibody responses and estimating the onset of the seroresponse in individual patients.MethodsAll available IgG and IgM phase I and II antibody measurements determined by immunofluorescence assay at month 3, 6, 12, and 48 from 2321 acute Q fever patients were retrospectively analyzed. Characteristic features of the antibody response were calculated. To model the seroresponse onset, serological data from patients diagnosed with a positive C. burnetii PCR test (n=364), and therefore with a known time of infection, were used as reference.ResultsIn 9083 IgG samples and 3260 IgM samples large heterogeneity in shape and magnitude of antibody responses was observed. Phase II reached higher levels than phase I, and IgG antibodies were more persistent than IgM. The estimated seroresponse latency allowed for determining the time since start of the seroresponse from the concentrations of the different antibodies against C. burnetii.ConclusionsThe extraordinary large serological dataset provides new insight into the kinetics of the immunoglobulins against C. burnetii antigens. This knowledge is useful for seroprevalence studies and helps to better understand infection dynamics

The use of typing methods and infection prevention measures to control a bullous impetigo outbreak on a neonatal ward

<p>Abstract</p> <p>Background</p> <p>We describe an outbreak of Bullous Impetigo (BI), caused by a (methicillin susceptible, fusidic acid resistant) <it>Staphylococcus aureus</it> (SA) strain, <it>spa-</it>type t408, at the neonatal and gynaecology ward of the Jeroen Bosch hospital in the Netherlands, from March-November 2011.</p> <p>Methods</p> <p>We performed an outbreak investigation with revision of the hygienic protocols, MSSA colonization surveillance and environmental sampling for MSSA including detailed typing of <it>SA</it> isolates. <it>Spa</it> typing was performed to discriminate between the SA isolates. In addition, Raman-typing was performed on all t408 isolates.</p> <p>Results</p> <p>Nineteen cases of BI were confirmed by SA positive cultures. A cluster of nine neonates and three health care workers (HCW) with <it>SA</it> t408 was detected. These strains were MecA^-, PVL^-, Exfoliative Toxin (ET)A^-, ETB⁺, ETAD^-, fusidic acid-resistant and methicillin susceptible. Eight out of nine neonates and two out of three HCW t408 strains yielded a similar Raman type. Positive t408 HCW were treated and infection control procedures were reinforced. These measures stopped the outbreak.</p> <p>Conclusions</p> <p>We conclude that treatment of patients and HCW carrying a predominant SA t408, and re-implementing and emphasising hygienic measures were effective to control the outbreak of SA t408 among neonates.</p

70-річчя члена-кореспондента НАН України В.І. Дубодєлова

16 квітня виповнилося 70 років відомому вченому в галузі металургії та технології металів членові-кореспондентові НАН України Вікторові Івановичу Дубодєлову

Large-scale production of LGR5-positive bipotential human liver stem cells

Background and Aims: The gap between patients on transplant waiting lists and available donor organs is steadily increasing. Human organoids derived from leucine‐rich repeat‐containing G protein‐coupled receptor 5 (LGR5)–positive adult stem cells represent an exciting new cell source for liver regeneration; however, culturing large numbers of organoids with current protocols is tedious and the level of hepatic differentiation is limited. Approach and Results: Here, we established a method for the expansion of large quantities of human liver organoids in spinner flasks. Due to improved oxygenation in the spinner flasks, organoids rapidly proliferated and reached an average 40‐fold cell expansion after 2 weeks, compared with 6‐fold expansion in static cultures. The organoids repopulated decellularized liver discs and formed liver‐like tissue. After differentiation in spinner flasks, mature hepatocyte markers were highly up‐regulated compared with static organoid cultures, and cytochrome p450 activity reached levels equivalent to hepatocytes. Conclusions: We established a highly efficient method for culturing large numbers of LGR5‐positive stem cells in the form of organoids, which paves the way for the application of organoids for tissue engineering and liver transplantation

Large-Scale Production of LGR5-Positive Bipotential Human Liver Stem Cells

Background and Aims: The gap between patients on transplant waiting lists and available donor organs is steadily increasing. H

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Alpha-hemolytic streptococci: a major pathogen of iatrogenic meningitis following lumbar puncture. Case reports and review of the literature

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Asymptomatic bacteriuria in women with diabetes mellitus - Effect on renal function after 6 years of follow-up

Background: The long-term consequences of asymptomatic bacteriuria (ASB) on renal function in women with diabetes mellitus (DM) are unknown. Methods: A prospective study was performed among women with type 1 or type 2 DM. Women with ASB (diagnosis based on findings from 1 urine culture specimen) were compared with women without ASB for differences in renal function development and incidence of hypertension. Results: A total of 644 women were included in the study (296 with type 1 DM and 348 with type 2 DM; mean [SD] age, 51 [15] years) and followed up for a mean (SD) duration of 6.1 (1.9) years. The prevalence of ASB was 17%. In women with DM and ASB, the creatinine clearance decreased from 87 mL/min (1.45 mL/s) at baseline to 76 mL/min (1.27 mL/s) at study end point; in women with DM without ASB the creatinine clearance decreased from 97 to 88 mL/min (from 1.62 to 1.47 mL/s). In the multivariate analyses, adjusted for age, length of follow- up, duration of DM, and microalbuminuria at baseline, no association was found between ASB and the relative or the absolute decrease in creatinine clearance; the same results were shown also when women with DM type 1 and women with DM type 2 were analyzed separately. Women with ASB developed hypertension more often than women without ASB (54% vs 37%; P=. 045), but there was no significant association in the multivariate analysis ( odds ratio, 1.5; 95% confidence interval, 0.7-3.6). Conclusion: Women with DM (type 1 or type 2) with ASB do not have an increased risk for a faster decline in renal function or the development of hypertension after 6 years of follow-up

Material objects of paint

The research paper ‘Material Objects of Paint’ is an extension or review of past endeavours by others to establish a credible argument that paint is capable of being adopted and used beyond conventional means in the creation of a broader range of works in the arena of visual art. The research covers the areas of the visual, theoretical and practical work directed at two objectives: The first objective is to study and report on the work of modernist and contemporary artists, writers and commentators. The second objective is to develop my potential to contribute to a greater knowledge and practical ability to extend the recognition of paint as a tool and vehicle in the area of Visual Arts

Relation between Q fever notifications and Coxiella burnetii infections during the 2009 outbreak in The Netherlands.

Contains fulltext : 109339.pdf (publisher's version ) (Open Access)Large outbreaks of Q fever in the Netherlands from 2007 to 2009 were monitored using notification data of acute clinical Q fever. However, the notification system provides no information on infections that remain subclinical or for which no medical attention is sought. The present study was carried out immediately after the peak of the 2009 outbreak to estimate the ratio between Coxiella burnetii infections and Q fever notifications. In 23 postcode areas in the high-incidence area, notification rates were compared with seroconversion rates in blood donors from whom serial samples were available. This resulted in a ratio of one Q fever notification to 12.6 incident infections of C. burnetii. This ratio is time and place specific and is based on a small number of seroconversions, but is the best available factor for estimating the total number of infections. In addition, as subclinical C. burnetii infection may lead to chronic Q fever, the ratio can be used to estimate the expected number of chronic Q fever patients in the coming years and as input for cost-benefit analyses of screening options