To examine asthma remission from childhood to middle age.
This was a population-based cohort study. In 1968 the Tasmanian Longitudinal Health Study enrolled 8583 7-year-old Tasmanian schoolchildren ...who were re-surveyed in 2004. Those reporting ever having asthma when last surveyed completed another questionnaire in 2007 ascertaining age at last asthma attack and asthma medication use. The main outcome measure was asthma remission, defined as no asthma attack for 2 years and no current asthma medication use, or no self-reported asthma in adult life but with parent-reported childhood asthma.
Of 5729 respondents to the 2004 survey, 1238 self-reported asthma. A further 573 denied asthma, but had parent-reported childhood asthma, giving a study sample of 1811. Asthma had remitted in 1177 (65.0%) of whom 649 (55.1%) were male. Childhood (OR 0.38, 95% CI 0.25 to 0.58) and later-onset allergic rhinitis (0.42, 0.29 to 0.63), childhood (0.66, 0.47 to 0.94) and later-onset eczema (0.66, 0.47 to 0.92), maternal asthma (0.66, 0.47 to 0.92) and childhood chronic bronchitis (0.56, 0.41 to 0.76) were negatively associated with remission. There was weaker evidence for a negative association between passive smoking (0.75, 0.54 to 1.04) and lower socio-economic status (p-trend 0.09) and remission. Childhood-onset asthma (3.76, 2.58 to 5.49) was more likely to remit than adult-onset asthma. Adult smoking was positively associated with remission in childhood-onset asthma (1.49, 1.06 to 2.09). Sex did not influence remission.
While inherited factors cannot be changed, the effect of allergic rhinitis or eczema on asthma remission might be altered by early, aggressive treatment. Every effort should be made to lessen passive exposure to tobacco smoke.
Purpose To measure right ventricular (RV) trabecular complexity by its fractal dimension (FD) in healthy subjects and patients with pulmonary hypertension (PH) and to assess its relationship with ...hemodynamic and functional parameters and future cardiovascular events. Materials and Methods This retrospective study used data acquired from May 2004 to October 2013 in 256 patients with newly diagnosed PH who underwent cardiac MRI, right-sided heart catheterization, and 6-minute walk distance testing, with median follow-up of 4.0 years. A total of 256 healthy control subjects underwent cardiac MRI only. Biventricular FD, volumes, and function were assessed on short-axis cine images. Reproducibility was assessed with the intraclass correlation coefficient, correlation between variables was assessed with the Pearson correlation test, and mortality prediction was compared by using uni- and multivariable Cox regression analyses. Results RV FD reproducibility had an intraclass correlation coefficient of 0.97 (95% confidence interval CI: 0.96, 0.98). RV FD was higher in patients with PH (median, 1.310; interquartile range IQR, 1.281-1.341) than in healthy subjects (median, 1.264; IQR, 1.242-1.295; P < .001), with the greatest difference near the apex. RV FD was associated with pulmonary vascular resistance (r = 0.30, P < .001). At univariable Cox regression analysis, RV FD was a significant predictor of death (hazard ratio HR, 1.256; 95% CI: 1.011, 1.560; P = .04); however, at multivariable analysis, RV FD did not enable prediction of survival independently of conventional parameters of RV remodeling (HR, 1.179; 95% CI: 0.871, 1.596; P = .29). Conclusion Fractal analysis of RV trabecular complexity is a highly reproducible measure of remodeling in patients with PH that is associated with afterload, although the gain in survival prediction over traditional markers is not significant. Published under a CC BY 4.0 license. Online supplemental material is available for this article.
OBJECTIVES
The purpose of this study was to determine the efficacy and risks of radiofrequency ablation of various forms of supraventricular tachycardia after Mustard and Senning operations for ...d-transposition of the great arteries.
BACKGROUND
In this patient group, the reported success rate of catheter ablation of intraatrial reentry tachycardia is about 70% with a negligible complication rate. There are no reports of the use of radiofrequency ablation to treat other types of supraventricular tachycardia.
METHODS
Standard diagnostic criteria were used to determine supraventricular tachycardia type. Appropriate sites for attempted ablation included 1) intraatrial reentry tachycardia: presence of concealed entrainment with a postpacing interval similar to tachycardia cycle length; 2) focal atrial tachycardia: a P-A interval ≤−20 ms; and 3) typical variety of atrioventricular (AV) node reentry tachycardia: combined electrographic and radiographic features.
RESULTS
Nine Mustard and two Senning patients underwent 13 studies to successfully ablate all supraventricular tachycardia substrates in eight (73%) patients. Eight of eleven (73%) patients having intraatrial reentry tachycardia, 3/3 having typical AV node reentry tachycardia, and 2/2 having focal atrial reentry tachycardia were successfully ablated. Among five patients having intraatrial reentry tachycardia (IART) and not having ventriculoatrial (V-A) conduction, two suffered high-grade AV block when ablation of the systemic venous portion of the medial tricuspid valve/inferior vena cava isthmus was attempted.
CONCLUSIONS
Radiofrequency catheter ablation can be effectively and safely performed for certain supraventricular tachycardia types in addition to intraatrial reentry. A novel catheter course is required for slow pathway modification. High-grade AV block is a potential risk of lesions placed in the systemic venous medial isthmus.
Measles Elimination in the United States Orenstein, Walter A.; Papania, Mark J.; Wharton, Melinda E.
The Journal of infectious diseases,
05/2004, Letnik:
189, Številka:
Supplement-1
Journal Article
Summary
Introduction
The hygiene hypothesis proposes that reduced exposure to infections in early life increases the risk of developing allergic conditions including allergic rhinitis. We examined ...the association between markers of the hygiene hypothesis and allergic rhinitis that developed before 7 years of age and allergic rhinitis that developed after 7 years of age.
Methods
The Tasmanian Longitudinal Health Study (TAHS) is a population‐based cohort (n=8583) study of respiratory disease. Participants have been followed from 7 to 44 years of age. Information on potential risk factors, allergies and respiratory symptoms was collected longitudinally. Using multi‐nomial logistic regression, exposure to siblings, infections, tonsillectomy and farm residence during childhood were examined as risk factors for allergic rhinitis that developed before or after 7 years of age. All analyses were adjusted for gender, maternal and paternal atopy, mother's age at participant's birth, paternal socio‐economic status in 1968 and personal socio‐economic status in 2004.
Results
Greater cumulative exposure to siblings before the age of 2 years was strongly inversely associated with early onset allergic rhinitis (<1 year sib exposure: OR=0.6, 95% CI 0.3–1.0; 1–3 years sib exposure: OR=0.6, 95% CI 0.4–0.9; >3 years sib exposure: OR=0.4, 95% CI 0.3–0.8) less so with later onset allergic rhinitis. The risk of early onset allergic rhinitis decreased with increasing viral infections (OR=0.7, 95% CI 0.5–0.9) during childhood. Having a tonsillectomy before 7 years of age increased the risk of early onset allergic rhinitis (OR=1.7, 95% CI 1.2–2.5). None of these factors was associated with later onset allergic rhinitis.
Conclusions
Exposures relevant to the hygiene hypothesis were important predictors for the development of early onset but less so for later onset allergic rhinitis. The exact mechanisms by which siblings and infections protect against allergic rhinitis are unclear. The stronger findings for earlier onset allergic rhinitis suggest that family structure and infections have most impact on disease risk in early life. Further research should focus on early onset allergic rhinitis when exploring causal explanations for any sibling effect.
Signal transducer and activator of transcription (STAT) proteins perform key roles in mediating signaling by cytokines and growth factors, including platelet-derived growth factor (PDGF). In ...addition, Src family kinases activate STAT signaling and are required for PDGF-induced mitogenesis in normal cells. One STAT family member, Stat3, has been shown to have an essential role in cell transformation by the Src oncoprotein. However, the mechanisms by which STAT-signaling pathways contribute to mitogenesis and transformation are not fully defined. We show here that disruption of Stat3 signaling by using dominant-negative Stat3β protein in NIH 3T3 fibroblasts suppresses c-Myc expression concomitant with inhibition of v-Src-induced transformation. Ectopic expression of c-Myc is able to partially reverse this inhibition, suggesting that c-Myc is a downstream effector of Stat3 signaling in v-Src transformation. Furthermore, c-myc gene knockout fibroblasts are refractory to transformation by v-Src, consistent with a requirement for c-Myc protein in v-Src transformation. In normal NIH 3T3 cells, disruption of Stat3 signaling with dominant-negative Stat3β protein inhibits PDGF-induced mitogenesis in a manner that is reversed by ectopic c-Myc expression. Moreover, inhibition of Src family kinases with the pharmacologic agent, SU6656, blocks Stat3 activation by PDGF. These findings, combined together, delineate the signaling pathway, PDGF → Src → Stat3 → Myc, that is important in normal PDGF-induced mitogenesis and subverted in Src transformation.
The left superior vena cava (LSVC) is the embryological precursor of the ligament of Marshall, which has been implicated in the initiation and maintenance of atrial fibrillation (AF). Rarely, the ...LSVC may persist and has been associated with some organized arrhythmias, though not with AF. We report 5 patients in whom the LSVC was a source of ectopy, initiating AF.
In 5 patients (4 men; age, 46+/-11 years) with symptomatic drug-refractory AF, ectopy from the LSVC resulting in AF was observed after pulmonary vein isolation. The ectopics were spontaneous in 2 and induced by isoproterenol in the others and preceded P-wave onset by 67+/-13 ms. During multielectrode or electroanatomic mapping, venous potentials were recorded circumferentially at the proximal LSVC near its junction with the coronary sinus (CS), but at the mid-LSVC level, they were recorded only on part of the circumference. The LSVC was electrically connected to the lateral left atrium (LA) and through the CS to the right atrium, with 4.1+/-2.3 CS-LSVC and 1.6+/-0.5 LA-LSVC connections per patient. Catheter ablation in the LSVC targeting these connections resulted in electrical isolation in 4 of the 5 patients without complications. After 15+/-10 months, the 4 patients with successful isolation, including 1 who had successful reablation for LA flutter, remained in sinus rhythm without drugs.
The LSVC can be the arrhythmogenic source of AF with connections to the CS and LA. Ablation of these connections resulted in electrical isolation.
Context. Realistic synthetic observations of theoretical source models are essential for our understanding of real observational data. In using synthetic data, one can verify the extent to which ...source parameters can be recovered and evaluate how various data corruption effects can be calibrated. These studies are the most important when proposing observations of new sources, in the characterization of the capabilities of new or upgraded instruments, and when verifying model-based theoretical predictions in a direct comparison with observational data. Aims. We present the SYnthetic Measurement creator for long Baseline Arrays (SYMBA), a novel synthetic data generation pipeline for Very Long Baseline Interferometry (VLBI) observations. SYMBA takes into account several realistic atmospheric, instrumental, and calibration effects. Methods. We used SYMBA to create synthetic observations for the Event Horizon Telescope (EHT), a millimetre VLBI array, which has recently captured the first image of a black hole shadow. After testing SYMBA with simple source and corruption models, we study the importance of including all corruption and calibration effects, compared to the addition of thermal noise only. Using synthetic data based on two example general relativistic magnetohydrodynamics (GRMHD) model images of M 87, we performed case studies to assess the image quality that can be obtained with the current and future EHT array for different weather conditions. Results. Our synthetic observations show that the effects of atmospheric and instrumental corruptions on the measured visibilities are significant. Despite these effects, we demonstrate how the overall structure of our GRMHD source models can be recovered robustly with the EHT2017 array after performing calibration steps, which include fringe fitting, a priori amplitude and network calibration, and self-calibration. With the planned addition of new stations to the EHT array in the coming years, images could be reconstructed with higher angular resolution and dynamic range. In our case study, these improvements allowed for a distinction between a thermal and a non-thermal GRMHD model based on salient features in reconstructed images.
AimTo assess whether the current starting age of 12 is suitable for diabetic retinopathy (DR) screening and whether diabetes duration should be taken into account when deciding at what age to start ...screening patients.Materials and methodsA retrospective analysis of 143 patients aged 12 years or younger who attended diabetic eye screening for the first time in the Birmingham, Solihull and Black Country Diabetic Eye Screening Programme was performed.ResultsThe mean age of the patients was 10.7 (7-12) years with 73 out of 143 aged below 12 years and 70 were 12 years of age. 98% had type 1 diabetes and mean diabetes duration was 5 (1 month-11 years) years. For those younger than 12 years, 7/73 (9.6%) had background DR (BDR), of these mean diabetes duration was 7 years (6-8). The youngest patient to present with DR was aged 8 years. In those aged 12 years, 5/70 (7.1%) had BDR; of these mean diabetes duration was 8 years (6-11). No patient developed DR before 6 years duration in either group.ConclusionsThe results show that no patient younger than the age of 12 had sight-threatening DR (STDR), but BDR was identified. Based on the current mission statement of the Diabetic Eye Screening Programme to identify STDR, 12 years of age is confirmed as the right age to start screening, but if it is important to diabetic management to identify first development of DR, then screening should begin after 6 years of diabetes diagnosis.
PDF
