EARSS: European Antimicrobial Resistance Surveillance System; gegevens uit Nederland (1999). Prevalentie en incidentie van resistentie voor Streptococcus pneumoniae en Staphylococcus aureus

In a porspective prevalence and incidence survey in The Netherlands in 1999 antimicrobial susceptibility data on invasive Streptococcus pneumoniae and Staphylococcus aureus infections were collected sithin the framework of European Antomicrobial Resistance Surveillance System (EARSS). The EARSS project covered approximately 40% of the Dutch population (extramural) and 40% of the total number of patient-days (intramural). Penicillin resistance in S. pneumoniae was minimal; only 9 of 767 (1,2%) isolates were non-susceptible. Resistance to oxacillin in S. aureus was low, only (0,3%) isolates were MRSA (mecA positive). The incidence of invasive S. pneumoniae was 117 cases/1.000.000 person-years; the incidence of invasive penicillin non-susceptible S. pneumoniae was 1 case/1.000.000 person-years. The incidence of invasive S. aureus infections was 0.25 cases/1000 patient-days; the incidence of invasive MRSA infections was 0.0006 cases/1000 patient-days. It may be concluded that resistance to antibiotics in these two pathogens, when compared to other European countries, is still very low.Gevoeligheid voor antimicrobiele middelen in Streptococcus pneumoniae en Staphylococcus aureus werd bepaald in 1999 in Nederland binnen het raamwerk van het European antomicrobial Resistance Surveillance System (EARSS). Het EARSS project had in Nederland een dekkingsgraad van 40% van de Nederlandse populatie (extramuraal) en 40% van het totale aantal patientdagen (intramuraal). Resistentiie tegen penicilline in S. pneumoniae was minimaal; slechts 9 van 767 (1,2%) isolatn waren niet gevoelig. Resistentie tegen oxacilline in S. aureus was ook laag; slechts 4 ((0,3%) isolaten waren MRSA. de incidentie van invasieve S. pneumoniae was 117 gevallen/1.000.000 persoonsjaren, de incidentie van invasieve penicilline niet gevoelige S. pneumoniae was 1 geval/1.000.000 persoonsjaren. De incidentie van invasieve S. aureus infecties was 0,25 gevallen/1000 patientdagen; de incidentie van invasieve MRSA infecties was 0,0006 gevallen/1000 patientdagen. hetis duidelijkj dat resistentie tegen antibiotica bij deze twee pathogenen in vergelijkijng tot andere Europese landen nog steeds erg laag is

Flavour-kinematics duality for Goldstone modes

Three scalar effective field theories have special properties in terms of non-linear symmetries, soft limits and on-shell constructability that arise from their Goldstone nature: the non-linear $\sigma$-model, multi-DBI theory and the special Galileon. We discuss how these theories are related via flavour-kinematic duality, analogous to the colour-kinematic duality between gravity and gauge theories. At the off-shell level, we identify a specific mapping between the three theories that is crucially dependent on their non-linear symmetries. Similarly, we demonstrate how the on-shell amplitudes factorise into BCJ numerators describing flavour and a scalar version of kinematics, naturally leading to the inclusion of graviton exchange in the $SO(M,N)$ non-linear $\sigma$-model. Finally, we map those numerators onto each other, and comment on a similar relation to tensor kinematics. Our results highlight a common structure that underlies the physics of different Goldstone modes.Comment: 22 pages, 4 figure

Whole genome sequencing as the ultimate tool to diagnose tuberculosis

AbstractIn the past two decades, DNA techniques have been increasingly used in the laboratory diagnosis of tuberculosis (TB). The (sub) species of the Mycobacterium tuberculosis complex are usually identified using reverse line blot techniques. The resistance is predicted by the detection of mutations in genes associated with resistance. Nevertheless, all cases are still subjected to cumbersome phenotypic resistance testing. The production of a strain-characteristic DNA fingerprint, to investigate the epidemiology of TB, is done by the 24-locus variable number tandem repeat (VNTR) typing. However, most of the molecular techniques in the diagnosis of TB can eventually be replaced by whole genome sequencing (WGS). Many international TB reference laboratories are currently working on the introduction of WGS; however, standardization in the international context is lacking. The European Centre for Infectious Disease Prevention and Control in Stockholm, Sweden organizes a yearly round of quality control on VNTR typing and in 2015 for the first time also WGS. In this first proficiency study, only three out of eight international TB laboratories produced WGS results in line with those of the reference laboratory. The whole process of DNA isolation, purification, quantification, sequencing, and analysis/interpretation of data is still under development. In this presentation, many aspects will be covered that influence the quality and interpretation of WGS results. The turn-around-time, analysis, and utility of WGS will be discussed. Moreover, the experiences in the use of WGS in the molecular epidemiology of TB in The Netherlands are detailed. It can be concluded that many difficulties still have to be conquered. The state of the art is that bacteria still have to be cultured to have sufficient quality and quantity of DNA for succesful WGS. The quality of sequencing has improved significantly over the past 7years, and the detection of mutations has, therefore, become more reliable. The resistance mutations detected in WGS are in line with the ones visualized in reverse line blot techniques. The turnover in the genome of M. tuberculosis is very low, ∼0.3–0.5 mutations per genome per year. However, there is a wide variation in the occurrence of mutations per strain and genotype. Still, the resolution of WGS in epidemiological typing is higher than that in VNTR typing; previously suggested epidemiological links by VNTR typing are sometimes refuted on the basis of WGS. Although WGS offers the highest resolution in typing, in a country like The Netherlands, there are many strains with a limited genetic distance up to 100 mutations, without an apparent epidemiological link between the respective cases. These lookalikes are presumably even more prevalent in settings where predominant genotypes of M. tuberculosis are circulating. In summary, WGS seems to yield a more reliable prediction of resistance by the (lack of) detection of mutations in all 25 genes ever associated with resistance. This may within a short while prevent the need for many phenotypic resistance tests. Although more robust algorithms need to be developed, the recognition of the (sub) species in the M. tuberculosis complex seems possible. The first detailed studies on the population structure of M. tuberculosis strains in The Netherlands provide more resolution in typing but also an interesting observation that a part of the strains are genetically so conserved that they are separated by less than 100 mutations. This demands a more extended and accurate validation and understanding of the utility of WGS in the epidemiology of TB

Randomized study of two different target levels of glycemic control within the acceptable range in type 2 diabetes - Effects on well-being at 1 year

OBJECTIVE - A randomized trial with 1-year follow-up was conducted in 23 general practices to study the relationship between target values for glycemic control and well-being in type 2 diabetes. RESEARCH DESIGN AND METHODS - A total of 176 patients with type 2 diabetes, aged 40-75 years, were included. General practitioners were encouraged to make decisions according to a standardized step-up regimen until the target level of glycemic control was reached. The random allocation to a strict or a less strict target level of glycemic control (fasting capillary glucose <6.5 or <8.5 mmol/l), change in HbA(1c) and fasting glucose, and initiating insulin or treatment with oral hypoglycemic agents were studied as putative determinants of scores on a type 2 diabetes symptom checklist, a profile of mood states, an affect balance scale, and general well-being. Adjustments were made for baseline scores on the outcome at issue. RESULTS - Positive affect (an odds ratio [OR] [95% CI] of 0.39 [0.19-0.83]) and perceived treatment burden (OR 0.48 [0.23-0.98]) were unfavorably altered in the group randomly allocated to stricter target levels (fasting capillary glucose <6.5 mmol/l). Patients who had a decrease in HbA(1c) of 1% or more tended to have comparatively favorable mood (OR displeasure score 0.35 [0.13-0.94]) and general well-being scores at 1 year (ORs of having unfavorable scores ranged from 0.4 to 0.5, NS). CONCLUSIONS - Perceived treatment burden and positive effect are unfavorably affected by random allocation to a strict target level for glycemic control. Improved glycemic control is associated with favorable mood and possibly general well-being in type 2 diabetes

Methicillin-Resistant Staphylococcus aureus in Pigs with Exudative Epidermitis

Despite a strict control program for methicillin-resistant Staphylococcus aureus (MRSA) in human medicine in the Netherlands, MRSA was cultured from exudative epidermitis lesions of 4 piglets on a breeding farm, 20 pigs on a supplier farm, and 2 workers on these farms. The MRSA strains were indistinguishable, suggesting direct transmission

Studies on Prn Variation in the Mouse Model and Comparison with Epidemiological Data

The virulence factor pertactin (Prn) is a component of pertussis vaccines and one of the most polymorphic Bordetella pertussis antigens. After the introduction of vaccination shifts in predominant Prn types were observed and strains with the Prn vaccine type (Prn1) were replaced by strains carrying non-vaccine types (Prn2 and Prn3), suggesting vaccine-driven selection. The aim of this study was to elucidate the shifts observed in Prn variants. We show that, although Prn2 and Prn3 circulated in similar frequencies in the 1970s and 1980s, in the 1990s Prn2 strains expanded and Prn3 strains disappeared, suggesting that in vaccinated populations Prn2 strains are fitter than Prn3 strains. We established a role for Prn in the mouse model by showing that a Prn knock-out (Prn-ko) mutation reduced colonization in trachea and lungs. Restoration of the mutation resulted in a significant increase in colonization compared to the knock-out mutant. The ability of clinical isolates with different Prn variants to colonize the mouse lung was compared. Although these isolates were also polymorphic at other loci, only variation in the promoter for pertussis toxin (ptxP) and Prn were found to contribute significantly to differences in colonization. Analysis of a subset of strains with the same ptxP allele revealed that the ability to colonize mice decreased in the order Prn1>Prn2 and Prn3. Our results are consistent with the predominance of Prn1 strains in unvaccinated populations. Our results show that ability to colonize mice is practically the same for Prn2 and Prn3. Therefore other factors may have contributed to the predominance of Prn2 in vaccinated populations. The mouse model may be useful to assess and predict changes in the B. pertussis population due to vaccination

Multi-centre evaluation of a phenotypic extended spectrum β-lactamase detection guideline in the routine setting

AbstractThis study aimed to evaluate the routine setting performance of a guideline for phenotypic detection of extended spectrum β-lactamases (ESBLs) in Enterobacteriaceae, recommending ESBL confirmation with Etest or combination disc for isolates with a positive ESBL screen test (i.e. cefotaxime and/or ceftazidime MIC >1 mg/L or an automated system ESBL warning). Twenty laboratories submitted 443 Enterobacteriaceae with a positive ESBL screen test and their confirmation test result (74% Escherichia coli, 12% Enterobacter cloacae, 8% Klebsiella pneumoniae, 3% Proteus mirabilis, 2% Klebsiella oxytoca). Presence of ESBL genes was used as reference test. Accuracy of local phenotypic ESBL detection was 88%. The positive predictive value (PPV) of local screen tests was 70%, and differed per method (Vitek-2: 69%, Phoenix: 68%, disc diffusion: 92%), and species (95% K. pneumoniae-27% K. oxytoca). A low PPV (3%) was observed for isolates with automated system alarm but third-generation cephalosporin MICs <2 mg/L. Local ESBL confirmation had a PPV and negative predictive value (NPV) of 93% and 90%, respectively. Compared with centrally performed confirmation tests, 7% of local tests were misinterpreted. Combination disc was more specific than Etest (91% versus 61%). Confirmation tests were not reliable for P. mirabilis and K. oxytoca (PPV 33% and 38%, respectively, although NPVs were 100%). In conclusion, performance of Etests could be enhanced by education of technicians to improve their interpretation, by genotypic ESBL confirmation of P. mirabilis and K. oxytoca isolates with positive phenotypic ESBL confirmation, and by interpreting isolates with a positive ESBL alarm but an MIC <2 mg/L for cefotaxime and ceftazidime as ESBL-negative

Связи изменений среднемесячных ОСО над Антарктикой и площади теплого тропического бассейна Тихого океана при современном потеплении климата

Объектом данного исследования выбраны изменения распределения среднемесячных значений ОСО над Антарктикой, а также площади ТТБ в западном полушарии. Предметом исследования есть изменения статистических связей между указанными процессами, происходившими за период современного потепления климата. Целью работы есть выявление их связей, которые на протяжении периода современного потепления климата усиливались устойчиво и ныне являются значимыми