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الطفل والكتاب : دراسة أدبية ونفسية
إن ردود أفعال الأطفال تجاه الأدب مثيرة للاهتمام على حد سواء من وجهة النظر النفسية والأدبية، وتتتبع الدراسة الاستكشافية التي أجراها نيكولاس تاكر العلاقة بين الطفل والكتاب باستخدام هذين المنظورين، من أول كتاب مصور للطفل إلى اللحظة التي يبدأ فيها القارئ المراهق في قراءة الأدب الموجه للكبار. وبالإضافة إلى ذلك، تدرس الدراسة بشكل نقدي الحجج التي تؤيد توخي الحذر والرقابة في اختيار الكتب المخصصة للأطفال، وتنظر في المقابل إلى ما يمكن أن تقدمه كتب الأطفال للقارئ البالغ. وتتراوح الانتقادات الحادة التي يقدمها المؤلف من أغاني الأطفال وقصص الجنيات إلى القصص المصورة والكتب الأكثر مبيعا وكتابات الأطفال الحديثة، وتقدم وجهة نظر متوازنة لموضوع مثير ومثير للجدل في بعض الأحيان.
Book
Reference values for healthy human myocardium using a T1 mapping methodology: results from the International T1 Multicenter cardiovascular magnetic resonance study
Background
T1 mapping is a robust and highly reproducible application to quantify myocardial relaxation of longitudinal magnetisation. Available T1 mapping methods are presently site and vendor specific, with variable accuracy and precision of T1 values between the systems and sequences. We assessed the transferability of a T1 mapping method and determined the reference values of healthy human myocardium in a multicenter setting.
Methods
Healthy subjects (n = 102; mean age 41 years (range 17–83), male, n = 53 (52%)), with no previous medical history, and normotensive low risk subjects (n=113) referred for clinical cardiovascular magnetic resonance (CMR) were examined. Further inclusion criteria for all were absence of regular medication and subsequently normal findings of routine CMR. All subjects underwent T1 mapping using a uniform imaging set-up (modified Look- Locker inversion recovery, MOLLI, using scheme 3(3)3(3)5)) on 1.5 Tesla (T) and 3 T Philips scanners. Native T1-maps were acquired in a single midventricular short axis slice and repeated 20 minutes following gadobutrol. Reference values were obtained for native T1 and gadolinium-based partition coefficients, λ and extracellular volume fraction (ECV) in a core lab using standardized postprocessing.
Results
In healthy controls, mean native T1 values were 950 ± 21 msec at 1.5 T and 1052 ± 23 at 3 T. λ and ECV values were 0.44 ± 0.06 and 0.25 ± 0.04 at 1.5 T, and 0.44 ± 0.07 and 0.26 ± 0.04 at 3 T, respectively. There were no significant differences between healthy controls and low risk subjects in routine CMR parameters and T1 values. The entire cohort showed no correlation between age, gender and native T1. Cross-center comparisons of mean values showed no significant difference for any of the T1 indices at any field strength. There were considerable regional differences in segmental T1 values. λ and ECV were found to be dose dependent. There was excellent inter- and intraobserver reproducibility for measurement of native septal T1.
Conclusion
We show transferability for a unifying T1 mapping methodology in a multicenter setting. We provide reference ranges for T1 values in healthy human myocardium, which can be applied across participating sites.
Journal Article
Cardiac stereotactic ablative radiotherapy for control of refractory ventricular tachycardia: initial UK multicentre experience
BackgroundOptions for patients with ventricular tachycardia (VT) refractory to antiarrhythmic drugs and/or catheter ablation remain limited. Stereotactic radiotherapy has been described as a novel treatment option.MethodsSeven patients with recurrent refractory VT, deemed high risk for either first time or redo invasive catheter ablation, were treated across three UK centres with non-invasive cardiac stereotactic ablative radiotherapy (SABR). Prior catheter ablation data and non-invasive mapping were combined with cross-sectional imaging to generate radiotherapy plans with aim to deliver a single 25 Gy treatment. Shared planning and treatment guidelines and prospective peer review were used.ResultsAcute suppression of VT was seen in all seven patients. For five patients with at least 6 months follow-up, overall reduction in VT burden was 85%. No high-grade radiotherapy treatment-related side effects were documented. Three deaths (two early, one late) occurred due to heart failure.ConclusionsCardiac SABR showed reasonable VT suppression in a high-risk population where conventional treatment had failed.
Journal Article
Importance of operator training and rest perfusion on the diagnostic accuracy of stress perfusion cardiovascular magnetic resonance
Background
Clinical evaluation of stress perfusion cardiovascular magnetic resonance (CMR) is currently based on visual assessment and has shown high diagnostic accuracy in previous clinical trials, when performed by expert readers or core laboratories. However, these results may not be generalizable to clinical practice, particularly when less experienced readers are concerned. Other factors, such as the level of training, the extent of ischemia, and image quality could affect the diagnostic accuracy. Moreover, the role of rest images has not been clarified.
The aim of this study was to assess the diagnostic accuracy of visual assessment for operators with different levels of training and the additional value of rest perfusion imaging, and to compare visual assessment and automated quantitative analysis in the assessment of coronary artery disease (CAD).
Methods
We evaluated 53 patients with known or suspected CAD referred for stress-perfusion CMR. Nine operators (equally divided in 3 levels of competency) blindly reviewed each case twice with a 2-week interval, in a randomised order, with and without rest images. Semi-automated Fermi deconvolution was used for quantitative analysis and estimation of myocardial perfusion reserve as the ratio of stress to rest perfusion estimates.
Results
Level-3 operators correctly identified significant CAD in 83.6% of the cases. This percentage dropped to 65.7% for Level-2 operators and to 55.7% for Level-1 operators (
p
< 0.001). Quantitative analysis correctly identified CAD in 86.3% of the cases and was non-inferior to expert readers (
p
= 0.56). When rest images were available, a significantly higher level of confidence was reported (
p
= 0.022), but no significant differences in diagnostic accuracy were measured (
p
= 0.34).
Conclusions
Our study demonstrates that the level of training is the main determinant of the diagnostic accuracy in the identification of CAD. Level-3 operators performed at levels comparable with the results from clinical trials. Rest images did not significantly improve diagnostic accuracy, but contributed to higher confidence in the results. Automated quantitative analysis performed similarly to level-3 operators. This is of increasing relevance as recent technical advances in image reconstruction and analysis techniques are likely to permit the clinical translation of robust and fully automated quantitative analysis into routine clinical practice.
Journal Article
Modelling accessibility of adult neurology care in Australia, 2020–2034
IntroductionIn 2015/2016, annual national expenditure on neurological conditions exceeded $A3 billion. However, a comprehensive study of the Australian neurological workforce and supply/demand dynamics has not previously been undertaken.MethodsCurrent neurological workforce was defined using neurologist survey and other sources. Workforce supply modelling used ordinary differential equations to simulate neurologist influx and attrition. Demand for neurology care was estimated by reference to literature regarding incidence and prevalence of selected conditions. Differences in supply versus demand for neurological workforce were calculated. Potential interventions to increase workforce were simulated and effects on supply versus demand estimated.ResultsModelling of the workforce from 2020 to 2034 predicted an increase in neurologist number from 620 to 89. We estimated a 2034 capacity of 638 024 Initial and 1 269 112 Review encounters annually, and deficits against demand estimated as 197 137 and 881 755, respectively. These deficits were proportionately greater in regional Australia, which has 31% of Australia’s population (Australian Bureau of Statistics) but is served by only 4.1% of its neurologists as determined by our 2020 survey of Australia and New Zealand Association of Neurologists members. Nationally, simulated additions to the neurology workforce had some effect on the review encounter supply deficit (37.4%), but in Regional Australia, this impact was only 17.2%.InterpretationModelling of the neurologist workforce in Australia for 2020–2034 demonstrates a significant shortfall of supply relative to current and projected demand. Interventions to increase neurologist workforce may attenuate this shortfall but will not eliminate it. Thus, additional interventions are needed, including improved efficiency and additional use of support staff.
Journal Article
Caseous Intracardiac Calcification: A Diagnostic Enigma
Intramyocardial calcification is a rare phenomenon often only discovered on postmortem. We describe the case of a healthy 69-year-old lady diagnosed with idiopathic caseous intracardiac calcification extending from the mitral valve annulus. We present high-quality images and propose an investigatory template for future cases.
Journal Article
Prevalence of myocardial crypts in a large retrospective cohort study by cardiovascular magnetic resonance
Background
Myocardial crypts are discrete clefts or fissures in otherwise compacted myocardium of the left ventricle (LV). Recent reports suggest a higher prevalence of crypts in patients with hypertrophic cardiomyopathy (HCM) and also within small samples of genotype positive but phenotype negative relatives. The presence of a crypt has been suggested to be a predictor of gene carrier status. However, the prevalence and clinical significance of crypts in the general population is unclear. We aimed to determine the prevalence of myocardial crypts in a large cohort of subjects using clinical cardiovascular magnetic resonance (CMR).
Methods
Consecutive subjects referred for clinical CMR during a 12-month period (n = 1020, age 52.6 ± 17, males: 61%) were included. Crypts were defined as >50% invagination into normal myocardium and their overall prevalence, location and shape was investigated and compared between different patient groups.
Results
The overall prevalence of crypts was 64/1020 (6.3%). In a predefined ‘normal’ control group the prevalence was lower (11/306, 3.6%, p = 0.031), but were equally prevalent in ischemic heart disease (12/236, 5.1%, p = n/s) and the combined non-ischemic cardiomyopathy (NICM) groups (24/373; 6.4%, p = n/s). Within the NICM group, crypts were significantly more common in HCM (9/76, 11.7%, p = 0.04) and hypertensive CM subjects (3/11, 27%, p = 0.03). In patients referred for CMR for family screening of inherited forms of CM, crypts were significantly more prevalent (10/41, 23%, p < 0.001), including a smaller group with a first degree relative with HCM (3/9, 33%, p = 0.01).
Conclusion
Myocardial crypts are relatively common in the normal population, and increasingly common in HCM and hypertensive cardiomyopathy. Crypts are also more frequently seen in normal phenotype subjects referred because of a family history of an inherited cardiomyopathy and HCM specifically. It is uncertain what the significance of crypts are in this group, and because of variability in the imaging protocols used and their relative frequency within the normal population, should not be used to clinically stratify these patients. Prospective studies are required to confirm the clinical significance of myocardial crypts, as their significance remains unclear.
Journal Article
Mortality in adult intensive care patients with severe systemic inflammatory response syndromes is strongly associated with the hypo-immune TNF −238A polymorphism
The systemic inflammatory response syndrome (SIRS) is associated with activation of innate immunity. We studied the association between mortality and measures of disease severity in the intensive care unit (ICU) and functional polymorphisms in genes coding for Toll-like receptor 4 (TLR4), macrophage migratory inhibitory factor (MIF), tumour necrosis factor (TNF) and lymphotoxin-alpha (LTA). Two hundred thirty-three patients with severe SIRS were recruited from one general adult ICU in a tertiary centre in the UK. DNA from patients underwent genotyping by 5′ nuclease assay. Genotype was compared to phenotype. Primary outcome was mortality in ICU. Minor allele frequencies were TLR4 +896G 7%, MIF 173C 16%, TNF −238A 10% and LTA +252G 34%. The frequency of the hypoimmune minor allele TNF −238A was significantly higher in patients who died in ICU compared to those who survived (p = 0.0063) as was the frequency of the two haplotypes LTA +252G, TNF −1031T, TNF −308G, TNF −238A and LTA +252G, TNF−1031T, TNF−308A and TNF−238A (p = 0.0120 and 0.0098, respectively). These findings re-enforce the view that a balanced inflammatory/anti-inflammatory response is the most important determinant of outcome in sepsis. Genotypes that either favour inflammation or its counter-regulatory anti-inflammatory response are likely to influence mortality and morbidity.
Journal Article
Cardiac magnetic resonance feature tracking in Kawasaki disease convalescence
Objective: The objective of this study was to determine whether left ventricular (LV) myocardial deformation indices can detect subclinical abnormalities in Kawasaki disease convalescence. We hypothesized that subclinical myocardial abnormalities due to inflammation represent an early manifestation of the disease that persists in convalescence.
Background: Myocardial inflammation has been described as a global finding in the acute phase of Kawasaki disease. Despite normal systolic function by routine functional measurements, reduced longitudinal strain and strain rate have been detected by echocardiography in the acute phase.
Methods and Results: Peak systolic LV myocardial longitudinal, radial, and circumferential strain and strain rate were examined in 29 Kawasaki disease convalescent patients (15 males; mean [standard deviation] age: 11 [6.6] years; median interval from disease onset: 5.8 [5.4] years) and 10 healthy volunteers (5 males; mean age: 14 [3.8] years) with the use of cardiac magnetic resonance (CMR) feature tracking. Routine indices of LV systolic function were normal in both groups. Comparisons were made between normal controls and (i) the entire Kawasaki disease group, (ii) Kawasaki disease subgroup divided by coronary artery involvement. Average longitudinal and circumferential strain at all levels was lower in patients compared to normal controls. In subgroup analysis, both Kawasaki disease patients with and without a history of coronary involvement had similar longitudinal and circumferential strain at all levels and lower when compared to controls. There were lower circumferential and longitudinal values in Kawasaki disease patients with persisting coronary artery lesions when compared to those with regressed ones.
Conclusion: In this CMR study in Kawasaki disease convalescent patients with preserved routine functional indices, we detected lower circumferential and longitudinal strain values compared to normal controls, irrespective of the coronary artery status.
Journal Article