Chest computed tomography in severe bronchopulmonary dysplasia: Comparing quantitative scoring methods.

PURPOSE: Bronchopulmonary dysplasia (BPD) is the most common complication of extreme preterm birth and structural lung abnormalities are frequently found in children with BPD. To quantify lung damage in BPD, three new Hounsfield units (HU) based chest-CT scoring methods were evaluated in terms of 1) intra- and inter-observer variability, 2) correlation with the validated Perth-Rotterdam-Annotated-Grid-Morphometric-Analysis (PRAGMA)-BPD score, and 3) correlation with clinical data. METHODS: Chest CT scans of children with severe BPD were performed at a median of 7 months corrected age. Hyper- and hypo-attenuated regions were quantified using PRAGMA-BPD and three new HU based scoring methods (automated, semi-automated, and manual). Intra- and inter-observer variability was measured using intraclass correlation coefficients (ICC) and Bland-Altman plots. The correlation between the 4 scoring methods and clinical data was assessed using Spearman rank correlation. RESULTS: Thirty-five patients (median gestational age 26.1 weeks) were included. Intra- and inter-observer variability was excellent for hyper- and hypo-attenuation regions for the manual HU method and PRAGMA-BPD (ICCs range 0.80-0.97). ICC values for the semi-automated HU method were poorer, in particular for the inter-observer variability of hypo- (0.22-0.71) and hyper-attenuation (-0.06-0.89). The manual HU method was highly correlated with PRAGMA-BPD score for both hyper- (ρs0.92, p < 0.001) and hypo-attenuation (ρs0.79, p < 0.001), while automated and semi-automated HU methods showed poor correlation for hypo- (ρs < 0.22) and good correlation for hyper-attenuation (ρs0.72-0.74, p < 0.001). Several scores of hyperattenuation correlated with the use of inhaled bronchodilators in the first year of life; two hypoattenuation scores correlated with birth weight. CONCLUSIONS: PRAGMA-BPD and the manual HU method have the best reproducibility for quantification of CT abnormalities in BPD.

Statistical modelling of groundwater contamination monitoring data: A comparison of spatial and spatiotemporal methods.

Field monitoring of groundwater contamination plumes is an important component of managing risks for downgradient receptors and remedial strategies that rely on monitored natural attenuation. Collection of groundwater quality data can however take a considerable effort and be associated with high cost. Here, we investigated the relative merits of analyzing groundwater quality data using spatial compared to spatiotemporal statistical modelling and assessed the accuracy of both methods and implications for data collection requirements. The aim of this was to determine whether the quantity of data collected can be reduced, while retaining the same level of estimation accuracy, by analyzing groundwater contamination data using a spatiotemporal model which "borrows strength" across time, rather than a spatial model for individual sampling events. To capture the variability encountered under field conditions, we used three hypothetical groundwater contamination plumes with increasing complexity, and site data for a large groundwater gasoline additive plume. The results show that spatiotemporal methods can increase efficiency markedly so that, in comparison with repeated spatial analysis, spatiotemporal methods can achieve the same level of performance but with smaller sample sizes.

Graph analysis of EEG resting state functional networks in dyslexic readers.

OBJECTIVE: Neuroimaging research suggested a mixed pattern of functional connectivity abnormalities in developmental dyslexia. We examined differences in the topological properties of functional networks between 29 dyslexics and 15 typically reading controls in 3rd grade using graph analysis. Graph metrics characterize brain networks in terms of integration and segregation. METHOD: We used EEG resting-state data and calculated weighted connectivity matrices for multiple frequency bands using the phase lag index (PLI). From the connectivity matrices we derived minimum spanning tree (MST) graphs representing the sub-networks with maximum connectivity. Statistical analyses were performed on graph-derived metrics as well as on the averaged PLI connectivity values. RESULTS: We found group differences in the theta band for two graph metrics suggesting reduced network integration and communication between network nodes in dyslexics compared to controls. CONCLUSION: Collectively, our findings point to a less efficient network configuration in dyslexics relative to the more proficient configuration in the control group. SIGNIFICANCE: Graph metrics relate to the intrinsic organization of functional brain networks. These metrics provide additional insights on the cognitive deficits underlying dyslexia and, thus, may advance our knowledge on reading development. Our findings add to the growing body literature suggesting compromised networks rather than specific dysfunctional brain regions in dyslexia.

Responsivity to dyslexia training indexed by the N170 amplitude of the brain potential elicited by word reading.

The present study examined training effects in dyslexic children on reading fluency and the amplitude of N170, a negative brain-potential component elicited by letter and symbol strings. A group of 18 children with dyslexia in 3rd grade (9.05±0.46years old) was tested before and after following a letter-speech sound mapping training. A group of 20 third-grade typical readers (8.78±0.35years old) performed a single time on the same brain potential task. The training was differentially effective in speeding up reading fluency in the dyslexic children. In some children, training had a beneficial effect on reading fluency ('improvers') while a training effect was absent in others ('non-improvers'). Improvers at pre-training showed larger N170 amplitude to words compared to non-improvers. N170 amplitude decreased following training in improvers but not in non-improvers. But the N170 amplitude pattern in improvers continued to differ from the N170 amplitude pattern across hemispheres seen in typical readers. Finally, we observed a positive relation between the decrease in N170 amplitude and gains in reading fluency. Collectively, the results that emerged from the present study indicate the sensitivity of N170 amplitude to reading fluency and its potential as a predictor of reading fluency acquisition.

Effects of aquifer thermal energy storage on groundwater quality and the consequences for drinking water production: a case study from The Netherlands.

We used data from an aquifer thermal energy storage (ATES) system located 570 m from a public water supply well field in the south of The Netherlands to investigate the relation between production of renewable energy with an ATES system and the production of drinking water. The data show that the groundwater circulation by the ATES system can impact chemical groundwater quality by introducing shallow groundwater with a different chemical composition at greater depth. However, the observed concentration changes are sufficiently small to keep groundwater suitable for drinking water production. Microbiological results showed that the ATES system introduced faecal bacteria in the groundwater and stimulated the growth of heterotrophic micro-organisms. At the studied site this forms no hygienic risk because of the long distance between the ATES wells and the public supply well field A further degradation of either chemical or microbiological groundwater quality however may necessitate additional water treatment which raises the energy requirements. The additional energy requirements for drinking water treatment may be up the same order of magnitude as the harvested energy by the ATES system.

Developmental and reproductive fitness of Orius laevigatus (Hemiptera: Anthocoridae) reared on factitious and artificial diets.

The developmental and reproductive fitness of the polyphagous predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) was compared on two factitious foods and four artificial diets. Adults fed factitious foods (Ephestia kuehniella Zeller eggs and Artemia franciscana Kellogg cysts) performed better than those fed artificial diets. Among the artificial diets, a diet composed of liver and ground beef scored better than meridic diets based on egg yolk. Within the egg yolk-based artificial diets, the developmental fitness varied proportionally with the amount of egg yolk present in the diet. A food switching experiment, in which nymphs and adults of the predator were fed either E. kuehniella eggs or an egg yolk-based artificial diet, showed that the impact of adult food on reproductive capacity was greater than that of nymphal food. An optimal adult food was able to wholly compensate for deficiencies incurred by an inferior artificial diet in the nymphal stage. A strong correlation was found between oocyte counts, lifetime oviposition, and the number of eggs laid after 8 d. A rapid dissection assay may thus be effective to reliably and economically assess the fitness of O. laevigatus as a function of the diet. This method also may prove useful as part of quality assurance procedure for commercially produced predators.

[Influence of patient's age and gender on doctors' decision making about coronary heart disease]. / Einfluss von Patientenalter und Patientengeschlecht auf ärztliche Entscheidungen bei koronarer Herzkrankheit.

BACKGROUND: Studies from the United Kingdom und the United States show that there are variations in doctors' decision making regarding coronary heart disease (CHD) and that patient attributes as well as physician characteristics have an impact on medical decisions regardless of the presented symptoms. This study examines how gender and age of patients influence primary care doctors' diagnostic and management decisions regarding CHD in Germany. METHODS: An experimental design with portrayed videotapes is used. Professional actors play the role of patients with symptoms of CHD. Videotapes were identical apart from varying patients' gender and age (55 vs. 75 years). A randomly selected sample of 128 primary care physicians viewed these videotapes in their practices. Afterwards physicians were asked to describe how to diagnose and treat the patient. RESULTS: Women were less likely to be asked about health related behaviours, less likely to get a CHD diagnosis and less likely to be referred to a cardiologist or other specialist. Younger patients were asked about medical history and smoking more frequently, but they were less likely to be asked about symptoms of pain and discomfort. Moreover, among older patients CHD diagnosis was mentioned more often and with higher certainty and medication appropriate for CHD was prescribed more often. DISCUSSION: Age and gender of patients influence primary care doctors' diagnostic and management strategies relating to CHD in Germany regardless of the presented symptoms.

[Endoscope-microscope combination (ENDO-OPMI) for endonasal paranasal sinus surgery]. / Endoskop-Mikroskop-Kombination (ENDO-OPMI) für die endonasale Nasennebenhöhlenchirurgie.

The development of modern endonasal sinus surgery is fundamentally based on the introduction of optical instrumentation. Endoscopes and microscopes are commonly used in such surgery. We tested a new combination of a stereoscopic single-channel endoscope with an operating microscope (ENDO-OPMI) for endonasal sinus surgery. This combination of the endoscope and microscope are connected in a way that results in a self-carried stereo-endoscope. To date, the ENDO-OPMI has been evaluated in cadaver studies and 7 cases of endonasal sinus surgery for chronic sinusitis. The trial was used to evaluate the clinical use of the current system and its possibilities for future developments. The ENDO-OPMI was demonstrated to be principally well-suited for endonasal sinus surgery. However, the current technical shortcomings make further developments necessary. Once these are implemented, the system should be superior to the use of an endoscope or microscope alone in endonasal surgery.

[Rapid determination of bactericidal kinetics by evaluating intracellular adenosine-triphosphate in bioluminescence]. / Détermination rapide de la vitesse de bactéricidie par évaluation de l'adénosine-triphosphate intracellulaire en bioluminescence.

Killing kinetics measurement is usually time-consuming and tedious. Bioluminescent adenosine-triphosphate (ATP) assay, after intracellular nucleotide release by bacterial lysis, selects very quickly normal from antibiotic-modified and dead bacteria. Two simultaneous assays are performed with more and less strong lysis reagents (nucleotide releasing bacterial NRB, nucleotide releasing somatic NRS, Lumac). Bioluminescence produced in a luciferine - luciferase system is measured with Biocounter M 2010 luminometer. Differential values of two assays reflect the intracellular ATP fraction of strongest bacteria in tested cultures. Killing curves of some beta lactamines (aminopenicillin and cephalosporins) were studied with active Escherichia coli and Streptococcus pneumoniae cultures. Bactericidal action was seen within few hours, and similar variations of intracellular ATP fraction and numbers of colony-forming units obtained by reference method were observed. This method, well-suited to large series of assays and very rapid (intracellular ATP assay within one minute), performs detailed killing kinetics in real time.

[A study of gamma-glutamyl-transpeptidase and of the ratio of IgA to transferrin in the pregnant woman (and when using oral contraception) and in the newborn (author's transl)]. / Etude de la gamma-glutamyl-transpeptidase et du rapport IgA sur transferrine chez la femme enceinte (et sous contraception orale) et le nouveau-né.

The authors confirm the absence of a marked variation in levels of gamma-glutamyl-transpeptidase in women under the influence of oestrogens, but a considerable rise in this enzyme in the newborn, particularly after delivery following vaginal obstetrical manoeuvre. They base these findings on 242 samples taken from pregnant women in the 3 trimesters of normal pregnancies and after delivery, and in the cord blood of newborn infants as well as in patients taking oral contraception. There is a slight rise in the levels of immunoglobulins A in the 3rd trimester of pregnancy. The overall rise in the blood levels of transferrin under the effect of oestrogens is confirmed. Norms were obtained for the levels of the IgA/T ratio which drops progressively as pregnancy progresses and with oral contraception. It has been found that in the last two trimesters the upper limit of the normal is 1 for the IgA/T ratio as compared with 1.9 in the general population. The study of these constants is of value when screening for maternal alcoholism and as a consequence for the prevention of the fetal alcohol syndrome.

[Fast immunochemical assay of proteins with Gemsaec centrifugal analyser. Application to serum transferrin and IgA assay]. / Dosage immunochimique rapide des protéines sur analyseur centrifuge gemsaec. Application au dosage de la transferrine et des IgA du sérum sanguin.

An automated method for measurement of specific proteins on a centrifugal analyser is reported. Based on the immunoprecipitin turbidimetric reaction enhanced by polyethylene-glycol, the technique, simple and fast, gives precise and accurate results with following cautions: the antigen and antibody concentrations must be carefully chosen according to defined specific antiserum, and two dilutions of each serum sample must be assayed to control quite satisfactory determination and exhibit any antigen excess error. Large series of serum transferrin and IgA assays were studied and compared with radial immunodiffusion and continuous-flow immunonephelometric method: good correlations prove the value of the reported method.