Epidemiological study of risk factors in pediatric asthma

Background: Childhood asthma is a major public health problem in Egypt and worldwide. Epidemiologic, physiologic, and social factors appear to be associated with an increased risk of asthma. Objective: The aim of the study was to determine the most frequent risk factors of childhood asthma exacerbation and severity in our community. Methods: This cross sectional study involved 206 asthmatic children, 5 to 15 years old. They were enrolled from the School Students Health Insurance facility of El-Matareya Teaching Hospital and from the Pediatric Outpatient Clinic of Saint Mark Charity Hospital representing several social and residential classes. They were assessed clinically and by peak expiratory flow rate (PEFR). Parents of children were interviewed for symptoms and some demographic, social, environmental, housing and familial data as well as asthma triggers through a comprehensive detailed questionnaire. Results: Residential distribution and social status were significantly associated with asthma severity as most moderate persistent asthmatics lived in semi-urban areas (70.8%) and belonged to the low-level segment of social classification (47.9%). In the majority of the study population (69.9%), a family member or more had a positive history of bronchial asthma, and this was especially evident in moderate persistent cases (70.8%). Passive smoking and dust triggered exacerbations in 48.6% and 65% of the studied sample respectively and in most moderate persistent asthmatics (83.4% and 93.7%). Most houses of moderate asthmatics were infested with cockroaches (91.7%) and domestic animals were present in 56.2%. Recurrent chest infections and cold/flu attacks were strongly associated with asthma exacerbation and severity (93.8% and 93.7% of moderate persistent cases respectively). Most moderate persistent asthmatics (91.7%) reported exercise-induced asthma while 64.6% stated that emotional stress triggered their symptoms. Indoor pollutants such as insecticides, household chemicals and odors were strongly associated with asthma severity and exacerbation especially in moderate persistent cases (triggered symptoms in 66.7%, 52.1% and 58.3% of cases respectively). Conclusion: Smoking, emotional stress and dust were the most significant triggers of asthma exacerbation and severity in our series. Identification and avoidance of risk factors for persistent asthma, combined with early institution of pharmacologic and other intervention strategies, may lead to a better outcome.Keywords: asthma severity; asthma triggers; children; residence; risk factors; smoking; social statusEgypt J Pediatr Allergy Immunol 2007; 5(1): 11-1

Epidemiological study of school performance and asthma medications among asthmatic Egyptian school children

Background: Childhood asthma is a major health problem in Egypt and worldwide. Barriers to reducing the burden of asthma include symptom-based rather than disease-based approaches, tendency of care to be ‘‘acute’’ rather than “regular” and cultural attitudes towards drugs and drug delivery systems. Objective: To measure the disease effect on school performance and to map asthma medications with respect to types, routes and course of use. Methods: This cross sectional study involved 206 Cairene asthmatic school children, enrolled from the school students’ health insurance facility of El-Matareya Teaching Hospital and the pediatric outpatient clinic of Saint Mark Charity Hospital representing different social classes and residential locations. Their ages ranged between 5 and 15 years and they comprised 100 males and 106 females. They were assessed clinically and by peak expiratory flowmetry. Parents or caregivers were interviewed about disease symptoms, school achievement and attendance and medications used including relievers and controllers, route and course of use, whether continuously, intermittently and/or during attacks. Results: Asthma had a strong impact on school achievement and school absence; 77.3% of study population reported school absence due to asthma and 41.3% reported weak to average school achievement. School performance was associated with asthma severity; the majority of moderate asthmatics (64.6%) had average and weak school performance. Number of days of school absence demonstrated highly significant relation with asthma severity; 43.6% of moderate asthmatics had 5-6 absent days/month and 33.4% had 3-4 absent days/month. Combined β2-agonists and xanthines was the most commonly used (54.8%) reliever therapy followed by β2-agonists alone (44.2%) while corticosteroids were the most common controllers used (97.6%). Therapy was taken mainly by oral than inhalation route. Other medications like cromolyns, anti-histamines, anti-leukotrienes and anti-cholinergics were rarely used. Both rectal and injection routes were rarely used also. Conclusion: Asthma has a social burden on asthmatic children as it affects both school achievement and school attendance. Medical management of asthma in Egyptian children still lags behind available medical knowledge. Patients’ and health care givers’ education is a cornerstone in improving the current status of asthma management in Egypt.Keywords: asthma medications; asthma severity; children; school performanceEgypt J Pediatr Allergy Immunol 2009;7(1):23-3

A de novo marker chromosome derived from 9p in a patient with 9p partial duplication syndrome and autism features: genotype-phenotype correlation

<p>Abstract</p> <p>Background</p> <p>Previous studies focusing on candidate genes and chromosomal regions identified several copy number variations (CNVs) associated with increased risk of autism or autism spectrum disorders (ASD).</p> <p>Case Presentation</p> <p>We describe a 17-year-old girl with autism, severe mental retardation, epilepsy, and partial 9p duplication syndrome features in whom GTG-banded chromosome analysis revealed a female karyotype with a marker chromosome in 69% of analyzed metaphases. Array CGH analysis showed that the marker chromosome originated from 9p24.3 to 9p13.1 with a gain of 38.9 Mb. This mosaic 9p duplication was detected only in the proband and not in the parents, her four unaffected siblings, or 258 ethnic controls. Apart from the marker chromosome, no other copy number variations (CNVs) were detected in the patient or her family. Detailed analysis of the duplicated region revealed: i) an area extending from 9p22.3 to 9p22.2 that was previously identified as a critical region for the 9p duplication syndrome; ii) a region extending from 9p22.1 to 9p13.1 that was previously reported to be duplicated in a normal individual; and iii) a potential ASD locus extending from 9p24.3 to 9p23. The ASD candidate locus contained 34 genes that may contribute to the autistic features in this patient.</p> <p>Conclusion</p> <p>We identified a potential ASD locus (9p24.3 to 9p23) that may encompass gene(s) contributing to autism or ASD.</p

Dynamics and within-host interaction of Theileria lestoquardi and T. ovis among naive sheep in Oman

Mixed species infections of Theileria spp. are common in nature. Experimental and epidemiological data suggest that mixed species infections elicit cross-immunity that can modulate pathogenicity and disease burden at the population level. The present study examined within-host interactions, over a period of 13 months during natural infections with two Theileria spp., pathogenic (T. lestoquardi) and non-pathogenic (T. ovis), amongst a cohort of naive sheep in Oman. In the first two months after exposure to infection, a high rate of mortality was seen among sheep infected with T. lestoquardi alone. However, subsequently mixed-infections of T. lestoquardi and T. ovis prevailed, and no further death occurred. The overall densities of both parasite species were significantly higher as single infection vs mixed infection and the higher relative density of pathogenic T. lestoquardi indicated a competitive advantage over T. ovis in mixed infection. The density of both species fluctuated significantly over time, with no difference in density between the very hot (May to August) and warm season (September to April). A high degree of genotype multiplicity was seen among T. lestoquardi infections, which increased with rising parasite density. Our results illustrate a potential competitive interaction between the two ovine Theileria spp., and a substantial reduction in the risk of mortality in mixed parasite infections, indicating that T. ovis confers heterologous protection against lethal T. lestoquardi infection

An LES Turbulent Inflow Generator using A Recycling and Rescaling Method

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.The present paper describes a recycling and rescaling method for generating turbulent inflow conditions for Large Eddy Simulation. The method is first validated by simulating a turbulent boundary layer and a turbulent mixing layer. It is demonstrated that, with input specification of mean velocities and turbulence rms levels (normal stresses) only, it can produce realistic and self-consistent turbulence structures. Comparison of shear stress and integral length scale indicates the success of the method in generating turbulent 1-point and 2-point correlations not specified in the input data. With the turbulent inlet conditions generated by this method, the growth rate of the turbulent boundary/mixing layer is properly predicted. Furthermore, the method can be used for the more complex inlet boundary flow types commonly found in industrial applications, which is demonstrated by generating non-equilibrium turbulent inflow and spanwise inhomogeneous inflow. As a final illustration of the benefits brought by this approach, a droplet-laden mixing layer is simulated. The dispersion of droplets in the near-field immediately downstream of the splitter plate trailing edge where the turbulent mixing layer begins is accurately reproduced due to the realistic turbulent structures captured by the recycling/rescaling method

Identification of Post-cardiac Arrest Blood Pressure Thresholds Associated With Outcomes in Children: An ICU-Resuscitation Study

INTRODUCTION: Though early hypotension after pediatric in-hospital cardiac arrest (IHCA) is associated with inferior outcomes, ideal post-arrest blood pressure (BP) targets have not been established. We aimed to leverage prospectively collected BP data to explore the association of post-arrest BP thresholds with outcomes. We hypothesized that post-arrest systolic and diastolic BP thresholds would be higher than the currently recommended post-cardiopulmonary resuscitation BP targets and would be associated with higher rates of survival to hospital discharge. METHODS: We performed a secondary analysis of prospectively collected BP data from the first 24 h following return of circulation from index IHCA events enrolled in the ICU-RESUScitation trial (NCT02837497). The lowest documented systolic BP (SBP) and diastolic BP (DBP) were percentile-adjusted for age, height and sex. Receiver operator characteristic curves and cubic spline analyses controlling for illness category and presence of pre-arrest hypotension were generated exploring the association of lowest post-arrest SBP and DBP with survival to hospital discharge and survival to hospital discharge with favorable neurologic outcome (Pediatric Cerebral Performance Category of 1-3 or no change from baseline). Optimal cutoffs for post-arrest BP thresholds were based on analysis of receiver operator characteristic curves and spline curves. Logistic regression models accounting for illness category and pre-arrest hypotension examined the associations of these thresholds with outcomes. RESULTS: Among 693 index events with 0-6 h post-arrest BP data, identified thresholds were: SBP \u3e 10th percentile and DBP \u3e 50th percentile for age, sex and height. Fifty-one percent (n = 352) of subjects had lowest SBP above threshold and 50% (n = 346) had lowest DBP above threshold. SBP and DBP above thresholds were each associated with survival to hospital discharge (SBP: aRR 1.21 [95% CI 1.10, 1.33]; DBP: aRR 1.23 [1.12, 1.34]) and survival to hospital discharge with favorable neurologic outcome (SBP: aRR 1.22 [1.10, 1.35]; DBP: aRR 1.27 [1.15, 1.40]) (all p \u3c 0.001). CONCLUSIONS: Following pediatric IHCA, subjects had higher rates of survival to hospital discharge and survival to hospital discharge with favorable neurologic outcome when BP targets above a threshold of SBP \u3e 10th percentile for age and DBP \u3e 50th percentile for age during the first 6 h post-arrest

Genetic Diversity and Population Structure of <i>Theileria annulata</i> in Oman

Background: Theileriosis, caused by a number of species within the genus Theileria, is a common disease of livestock in Oman. It is a major constraint to the development of the livestock industry due to a high rate of morbidity and mortality in both cattle and sheep. Since little is currently known about the genetic diversity of the parasites causing theileriosis in Oman, the present study was designed to address this issue with specific regard to T. annulata in cattle. Methods Blood samples were collected from cattle from four geographically distinct regions in Oman for genetic analysis of the Theileria annulata population. Ten genetic markers (micro- and mini-satellites) representing all four chromosomes of T. annulata were applied to these samples using a combination of PCR amplification and fragment analysis. The resultant genetic data was analysed to provide a first insight into the structure of the T. annulata population in Oman. Results: We applied ten micro- and mini-satellite markers to a total of 310 samples obtained from different regions (174 [56%] from Dhofar, 68 [22%] from Dhira, 44 [14.5%] from Batinah and 24 [8%] from Sharqia). A high degree of allelic diversity was observed among the four parasite populations. Expected heterozygosity for each site ranged from 0.816 to 0.854. A high multiplicity of infection was observed in individual hosts, with an average of 3.3 to 3.4 alleles per locus, in samples derived from Batinah, Dhofar and Sharqia regions. In samples from Dhira region, an average of 2.9 alleles per locus was observed. Mild but statistically significant linkage disequilibrium between pairs of markers was observed in populations from three of the four regions. In contrast, when the analysis was performed at farm level, no significant linkage disequilibrium was observed. Finally, no significant genetic differentiation was seen between the four populations, with most pair-wise FST values being less than 0.03. Slightly higher FST values (GST’ = 0.075, θ = 0.07) were detected when the data for T. annulata parasites in Oman was compared with that previously generated for Turkey and Tunisia. Conclusion: Genetic analyses of T. annulata samples representing four geographical regions in Oman revealed a high level of genetic diversity in the parasite population. There was little evidence of genetic differentiation between parasites from different regions, and a high level of genetic diversity was maintained within each sub-population. These findings are consistent with a high parasite transmission rate and frequent movement of animals between different regions in Oman