Issue 1 - "Update on adverse respiratory effects of outdoor air pollution" Part 2): Outdoor air pollution and respiratory diseases: Perspectives from Angola, Brazil, Canada, Iran, Mozambique and Portugal.

OBJECTIVE: To analyse the GARD perspective on the health effects of outdoor air pollution, and to synthesise the Portuguese epidemiological contribution to knowledge on its respiratory impact. RESULTS: Ambient air pollution has deleterious respiratory effects which are more apparent in larger, densely populated and industrialised countries, such as Canada, Iran, Brazil and Portugal, but it also affects people living in low-level exposure areas. While low- and middle-income countries (LMICs), are particularly affected, evidence based on epidemiological studies from LMICs is both limited and heterogeneous. While nationally, Portugal has a relatively low level of air pollution, many major cities face with substantial air pollution problems. Time series and cross-sectional epidemiological studies have suggested increased respiratory hospital admissions, and increased risk of respiratory diseases in people who live in urban areas and are exposed to even a relatively low level of air pollution. CONCLUSIONS: Adverse respiratory effects due to air pollution, even at low levels, have been confirmed by epidemiological studies. However, evidence from LMICs is heterogeneous and relatively limited. Furthermore, longitudinal cohort studies designed to study and quantify the link between exposure to air pollutants and respiratory diseases are needed. Worldwide, an integrated approach must involve multi-level stakeholders including governments (in Portugal, the Portuguese Ministry of Health, which hosts GARD-Portugal), academia, health professionals, scientific societies, patient associations and the community at large. Such an approach not only will garner a robust commitment, establish strong advocacy and clear objectives, and raise greater awareness, it will also support a strategy with adequate measures to be implemented to achieve better air quality and reduce the burden of chronic respiratory diseases (CRDs).

Detection and function of lipopolysaccharide and its purified lipid A after treatment with auxiliary chemical substances and calcium hydroxide dressings used in root canal treatment.

AIM: To investigate the influence of auxiliary chemical substances (ACSs) and calcium hydroxide [Ca(OH)2 ] dressings on lipopolysaccharides (LPS)/lipid A detection and its functional ability in activating Toll-like receptor 4 (TLR4). METHODOLOGY: Fusobacterium nucleatum pellets were exposed to antimicrobial agents as following: (i) ACS: 5.25%, 2.5% and 1% sodium hypochlorite solutions (NaOCl), 2% chlorhexidine (CHX) (gel and solution) and 17% ethylenediaminetetraacetic acid (EDTA); (ii) intracanal medicament: Ca(OH)2 paste for various periods (1 h, 24 h, 7 days, 14 days and 30 days); (iii) combination of substances: (a) 2.5% NaOCl (1 h), followed by 17% EDTA (3 min) and Ca(OH)2 (7 days); (b) 2% CHX (1 h), afterwards, 17% EDTA (3 min) followed by Ca(OH)2 (7 days). Saline solution was the control. Samples were submitted to LPS isolation and lipid A purification. Lipid A peaks were assessed by matrix-assisted laser desorption ionization time-of-flight mass spectrom (MALDI-TOF MS) whilst LPS bands by SDS-PAGE separation and silver staining. TLR4 activation determined LPS function activities. Statistical comparisons were carried out using one-way anova with Tukey-Kramer post-hoc tests at the 5% significance level. RESULTS: Matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of control lipid A demonstrated the ion cluster at mass/charge (m/z) 1882 and an intense band in SDS-PAGE followed by silver staining of control LPS. In parallel, LPS control induced a robust TLR4 activation when compared to ACS (P ≤ .001). 5.25% NaOCl treatment led to the absence of lipid A peaks and LPS bands, whilst no changes occurred to lipid A/LPS after treatment with others ACS. Concomitantly, 5.25% NaOCl-treated LPS did not activate TLR4 (P < .0001). As for Ca(OH)2 , lipid A was not detected by MALDI-TOF nor by gel electrophoresis within 24 h. LPS treated with Ca(OH)2 was a weak TLR4 activator (P < .0001). From 24 h onwards, no significant differences were found amongst the time periods tested (P > 0.05). The addition of Ca(OH)2 for 7 days to cells treated either with 2.5% NaOCl or 2% CHX led to the absence of lipid A peaks and LPS bands, leading to a lower activation of TLR4. CONCLUSION: 5.25% NaOCl and Ca(OH)2 dressings from 24 h onwards were able to induce both, loss of lipid A peaks and no detection of LPS bands, rendering a diminished immunostimulatory activity through TLR4.

The school as a health promoter for children with asthma: The purpose of an education programme.

BACKGROUND: Not only is asthma one of the leading causes of hospitalisation in children under 15 years and one of the main reasons for primary care outpatient visits, it also accounts for 13 million lost days of school annually, which can affect children's learning, integration at school and overall academic achievements. MATERIAL AND METHODS: This review article highlights the important role of the school in helping children and adolescents to control and manage their asthma through integrated and coordinated actions of health professionals, school staff, family, and the community. RESULTS: We recommended key elements for a multidisciplinary team asthma school programme that can be replicated and implemented especially in developing countries where children and adolescents are in a more disadvantaged environment. CONCLUSION: This multidisciplinary asthma school intervention when demonstrated with efficacy can be applied in the context of the real world, where many children and families who need care the most currently do not receive it.

Timing of voiding cystourethrogram in the investigation of urinary tract infections in children.

OBJECTIVE: To determine whether the detection of vesicoureteral reflux (VUR) in children with a urinary tract infection (UTI) is more likely if the voiding cystourethrogram (VCUG) is performed early (within the first 7 days after diagnosis) or late (>7 days after diagnosis). STUDY DESIGN: We conducted a retrospective case review of children <5 years of age admitted with a first episode of UTI to a tertiary care pediatric hospital over a 2-year period. Timing of the VCUG was at the discretion of the attending pediatrician. Differences in age, sex, mean time to performing the VCUG, and incidence of VUR between the 2 groups (VCUG performed early vs late) were compared by using Student t test (for age) and chi(2) test (for sex and incidence of VUR). Potential confounders (age and sex) were included in a multiple logistic regression analysis. RESULTS: A total of 162 patients were eligible for inclusion. Mean age was 181 days, and 43.8% were female. The incidence of VUR was 21.6%. The early group consisted of 82 patients, and the late group consisted of 80. No significant difference was found for age or sex or for the incidence of reflux (17.1% vs 26.3%, P =.219), with a crude odds ratio of.59 (95% CI 0.3-1.2, P >.05). CONCLUSION: The rate of detection of VUR in children with a first episode of UTI does not increase when the VCUG is done early (within the first 7 days of diagnosis) rather than later.

Risk factors for breast cancer mortality among the National Breast Screening Study of Canada participants.

We studied the relationship between risk factor information and breast cancer mortality by means of a case control study, nested within the population of the National Breast Screening Study of Canada (NBSS). The characteristics of women aged 40-59 years, identified at the initial screen, who subsequently died of breast cancer up to 7 years from the initial screen, were compared with those of controls drawn from the same population. Among the factors evaluated in this study, number of live births and presence of symptoms in the breast revealed on direct questioning were found to be significantly related to breast cancer mortality. The results suggest a decrease in risk of dying of breast cancer associated with one or more live births (OR: 0.79, 95% CI: 0.68, 0.93), and an increase in risk of dying of breast cancer associated with symptoms in the breast revealed on direct questioning at the initial screen (OR: 2.01, 95% CI: 1.20, 3.37).

Association between duration of neonatal hospital stay and readmission rate.

OBJECTIVE: A recent rapid decrease in the duration of neonatal hospital stay in Ontario, Canada, enabled us to study the association between healthy infants' age at neonatal hospital discharge and subsequent readmission rates. DESIGN: (1) Population-based and (2) single hospital-based retrospective studies. SETTING AND STUDY POPULATION: (1) A total of 920,554 healthy infants with a birth weight of 2500 gm or more, born in Ontario from 1987 to 1994. (2) Infants with a birth weight of 2500 gm or more, born during the same period, and readmitted before 15 days from home to the Hospital for Sick Children for jaundice or dehydration. MEASUREMENT: Duration of neonatal stay in the hospital and readmission rates were measured, and diagnostic codes were analyzed. Severity of illness was evaluated in infants readmitted to our hospital. RESULTS: In Ontario the mean length of stay decreased from 4.5 days to 2.7 days (p = 0.000), and the readmission rate during the first 2 weeks of life increased from 12.9 to 20.7 per 1000 (p = 0.000). Increased rates of readmission were most marked for jaundice and dehydration. The infants readmitted to our hospital had evidence of increased severity of illness as indicated by higher serum bilirubin and sodium concentrations. Two deaths occurred in infants with hypernatremic dehydration, one in 1992-1993 and another in 1993-1994. CONCLUSIONS: In Ontario, shorter neonatal hospital stay was associated with increased readmission rates for conditions that may not give rise to symptoms or signs on days 1 to 3 of life. In our hospital the severity of jaundice and dehydration in readmitted infants increased. The severity-of-illness data raise the question of whether shorter neonatal hospital stay of apparently healthy infants is always safe. Decisions to discharge infants should be based on rigorous evaluation of individual infants.