RESUMEN
BACKGROUND: Home fungus exposures may be associated with development or worsening of asthma. Little is known about the effects of school/classroom fungus exposures on asthma morbidity in students. OBJECTIVE: To evaluate the association of school-based fungus exposures on asthma symptoms in both fungus-sensitized and nonsensitized students with asthma. METHODS: In this prospective study, 280 children with asthma from 37 inner-city schools were phenotypically characterized at baseline and followed-up for 1 year. Fungal spores were collected by using a Burkard air sampler twice during the school year. Clinical outcomes were evaluated throughout the school year and linked to classroom-specific airborne spore sampling. The primary outcome was days with asthma symptoms per 2-week period. RESULTS: Fungal spores were present in all classroom samples. The geometric mean of the total fungi was 316.9 spores/m3 and ranged from 15.0 to 59,345.7 spores/m3. There was variability in total fungus quantity between schools and classrooms within the same school. Mitospores were the most commonly detected fungal grouping. Investigation of the individual mitospores revealed that exposure to Alternaria was significantly associated with asthma symptom days in students sensitized to Alternaria (OR = 3.61, CI = 1.34-9.76, P = .01), but not in children not sensitized to Alternaria (OR = 1.04, CI = 0.72-1.49, P = .85). Students sensitized to Alternaria and exposed to high levels (≥75th percentile exposure) had 3.2 more symptom days per 2-week period as compared with students sensitized but exposed to lower levels. CONCLUSION: Children with asthma who are sensitized to Alternaria and exposed to this fungus in their classroom may have significantly more days with asthma symptoms than those who were sensitized and not exposed. CLINICAL TRIAL REGISTRATION: Clinicaltrials.govNCT01756391.
Asunto(s)
Alérgenos/inmunología , Alternaria/inmunología , Asma/inmunología , Exposición a Riesgos Ambientales/estadística & datos numéricos , Hipersensibilidad/epidemiología , Esporas Fúngicas/inmunología , Población Urbana , Microbiología del Aire , Contaminación del Aire Interior , Asma/epidemiología , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Prospectivos , Instituciones Académicas , Estados Unidos/epidemiologíaRESUMEN
Statistically reliable, abridged, period life tables were produced for 88.7% of U.S. census tracts (65,662). A battery of tests revealed that the census-tract life table functions followed expected patterns; their distribution about state and U.S. values showed no aberrations; and their weighted mean values compared well with state- and national-level estimates. The weighted mean life expectancy at birth for the 65,662 census tracts was 78.7 years compared with the official U.S. estimate of 78.8 years in midyear 2013. The results of this study concur with previous research showing that a minimum population size of 5,000 is acceptable, with the caveat that missing age-specific death counts cannot be ignored. The methodology developed for this study addressed the issues of small populations and zero deaths as robustly as possible, although it is not without error.
Asunto(s)
Encuestas Epidemiológicas/métodos , Esperanza de Vida/tendencias , Tablas de Vida , Análisis de Área Pequeña , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Proyectos de Investigación , Factores Socioeconómicos , Estados Unidos/epidemiología , Adulto JovenRESUMEN
Desktop dust has been studied as a source of food allergen, but not as a source of potential aeroallergen exposure. Thirty-six wiped samples from desktop surfaces were collected from preschools and schools. Samples were analyzed for detectable levels of common aeroallergens including Alternaria, cockroach, dog, dust mite, cat, mouse, and rat allergens by immunoassay. Mouse allergen was the most prevalent, detectable in 97.2% of samples. Cat allergen was detectable in 80.6% of samples, and dog allergen was detectable in 77.8% of samples. Other allergens were not as prevalent. Mouse was the only allergen that was highly correlated with settled floor dust collected from the same rooms (r = 0.721, P < 0.001). This is the first study to detect aeroallergens on desktop surfaces by using moist wipes. Allergens for mouse, cat, and dog were highly detectable in wipes with mouse desktop surface levels correlating with levels in vacuumed floor dust.
Asunto(s)
Contaminación del Aire Interior/análisis , Alérgenos/análisis , Polvo/análisis , Exposición a Riesgos Ambientales/análisis , Instituciones Académicas , Animales , Gatos , Niño , Preescolar , Perros , Humanos , Ratones , Población UrbanaRESUMEN
BACKGROUND: Students spend a large portion of their day in classrooms which may be a source of mold exposure. We examined the diversity and concentrations of molds in inner-city schools and described differences between classrooms within the same school. METHODS: Classroom airborne mold spores, collected over a 2 day period, were measured twice during the school year by direct microscopy. RESULTS: There were 180 classroom air samples collected from 12 schools. Mold was present in 100% of classrooms. Classrooms within the same school had differing mold levels and mold diversity scores. The total mold per classroom was 176.6 ± 4.2 spores/m3 (geometric mean ± standard deviation) and ranged from 11.2 to 16,288.5 spores/m3. Mold diversity scores for classroom samples ranged from 1 to 19 (7.7 ± 3.5). The classroom accounted for the majority of variance (62%) in the total mold count, and for the majority of variance (56%) in the mold diversity score versus the school. The species with the highest concentrations and found most commonly included Cladosporium (29.3 ± 4.2 spores/m3), Penicillium/Aspergillus (15.0 ± 5.4 spores/m3), smut spores (12.6 ± 4.0 spores/m3), and basidiospores (6.6 ± 7.1 spores/m3). CONCLUSIONS: Our study found that the school is a source of mold exposure, but particularly the classroom microenvironment varies in quantity of spores and species among classrooms within the same school. We also verified that visible mold may be a predictor for higher mold spore counts. Further studies are needed to determine the clinical significance of mold exposure relative to asthma morbidity in sensitized and non-sensitized asthmatic children.
Asunto(s)
Contaminación del Aire Interior/análisis , Hongos/aislamiento & purificación , Instituciones Académicas/estadística & datos numéricos , Alérgenos/inmunología , Niño , Recuento de Colonia Microbiana , Hongos/clasificación , Humanos , Estaciones del Año , Esporas Fúngicas/citología , Esporas Fúngicas/inmunología , Población UrbanaRESUMEN
BACKGROUND: Most studies of indoor allergens have focused on the home environment. However, schools may be an important site of allergen exposure for children with asthma. We compared school allergen exposure to home exposure in a cohort of children with asthma. Correlations between settled dust and airborne allergen levels in classrooms were examined. METHODS: Settled dust and airborne samples from 12 inner-city schools were analyzed for indoor allergens using multiplex array technology (MARIA). School samples were linked to students with asthma enrolled in the School Inner-City Asthma Study (SICAS). Settled dust samples from students' bedrooms were analyzed similarly. RESULTS: From schools, 229 settled dust and 197 airborne samples were obtained. From homes, 118 settled dust samples were obtained. Linear mixed regression models of log-transformed variables showed significantly higher settled dust levels of mouse, cat and dog allergens in schools than homes (545% higher for Mus m 1, estimated absolute difference 0.55 µg/g, p < 0.0001; 198% higher for Fel d 1, estimated absolute difference 0.13 µg/g, p = 0.0033; and 144% higher for Can f 1, estimated absolute difference 0.05 µg/g, p = 0.0008). Airborne and settled dust Mus m 1 levels in classrooms were moderately correlated (r = 0.48; p < 0.0001). There were undetectable to very low levels of cockroach and dust mite allergens in both homes and schools. CONCLUSION: Mouse allergen levels in schools were substantial. In general, cat and dog allergen levels were low, but detectable, and were higher in schools. Aerosolization of mouse allergen in classrooms may be a significant exposure for students. Further studies are needed to evaluate the effect of indoor allergen exposure in schools on asthma morbidity in students with asthma.
Asunto(s)
Alérgenos/análisis , Asma/epidemiología , Exposición a Riesgos Ambientales , Vivienda , Instituciones Académicas , Población Urbana , Animales , Gatos , Niño , Perros , Polvo/análisis , Femenino , Humanos , Masculino , Ratones , Estudiantes , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Endotoxins are stimulators of the immune system and, despite their potential to protect against allergy, have been associated with early wheezing and asthma morbidity. OBJECTIVE: To compare inner-city school endotoxin exposure with home endotoxin exposure in children with asthma. METHODS: Students with asthma were recruited from 12 urban elementary schools. Settled and airborne dust samples, linked to enrolled students, were collected from school classrooms, gymnasiums, and cafeterias twice during the academic year. For comparison, settled dust was collected once from the bedrooms of students with asthma. RESULTS: Two hundred twenty-nine school settled dust samples and 118 bedroom settled dust samples were collected and analyzed for endotoxin. The median endotoxin concentration for school samples was 13.4 EU/mg (range, 0.7-360.7 EU/mg) and for home samples was 7.0 EU/mg (range = LLOD-843.0 EU/mg). The median concentration within each individual school varied from 6.6 EU/mg to 24.0 EU/mg. One hundred four students with asthma had matched classroom and bedroom endotoxin exposure measurements performed in the same season and demonstrated significantly higher concentrations of endotoxin in the students' classrooms (mean log value, 1.13 vs 0.99, P = .04). The median of the classrooms was 12.5 EU/mg compared with their bedrooms, with a median of 7.0 EU/mg. Within the school environment, no significant difference was seen between the fall and spring samples (mean log value 1.14 vs 1.09; P = .35). CONCLUSION: Inner-city children with asthma were exposed to higher concentrations of endotoxin in their classrooms as compared with their bedrooms. Further studies are needed to evaluate school endotoxin exposure as a factor in asthma morbidity.
Asunto(s)
Alérgenos/inmunología , Asma/inmunología , Polvo/inmunología , Endotoxinas/análisis , Adolescente , Contaminación del Aire Interior , Asma/epidemiología , Niño , Endotoxinas/inmunología , Femenino , Vivienda , Humanos , Masculino , Massachusetts/epidemiología , Instituciones Académicas , Estaciones del Año , Población UrbanaAsunto(s)
Asma/diagnóstico , Monitoreo Fisiológico/instrumentación , Asma/fisiopatología , Niño , Preescolar , Femenino , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Aplicaciones Móviles , Ápice del Flujo Espiratorio/fisiología , Instituciones Académicas , Espirometría/instrumentación , Espirometría/métodos , Capacidad Vital/fisiologíaAsunto(s)
Asma/psicología , Hipersensibilidad/psicología , Adolescente , Factores de Edad , Niño , Preescolar , Estudios de Cohortes , Humanos , Padres , Estudiantes , Encuestas y Cuestionarios , Población UrbanaRESUMEN
The objective of this study was to screen and evaluate the zinc deficiency tolerance among eight apple rootstocks, i.e., Malus baccata, M. rockii, M. xiaojinensis, M. sikkimensis, M. sieversii, M. robusta, M. hupehensis and Malus 'Flame'. The experiment took these 8 kinds of root-stocks as the research materials to observe and analyze the index of the rootstock's height, dry biomass, root architecture and zinc concentration, and with help of the fuzzy membership function to work out a comprehensive evaluation on their zinc deficiency tolerance. The result showed that several obvious zinc deficiency symptoms were observed in three kinds of rootstocks (M. rockii, M. sikkimensis and M. sieversii), such as dwarfed plant and newborn small leaves, while such symptoms were not obvious in M. xiaojinensis and M. 'Flame'. The plant biomass, height and zinc accumulation of aerial part greatly decreased under zinc deficiency stress, while smaller reduction was observed in M. xiaojinensis than in other rootstocks. M. xiaojinensis and M. baccata had higher zinc concentrations in leaves than others. According to the fuzzy membership function and cluster analysis, the resistance of the eight apple rootstocks to zinc deficiency was ranked: M. xiaojinensis was the highest one; M. 'Flame' was the second; M. baccata, M. sikkimensis, M. robusta and M. hupehensis were rather weaker; M. rockii and M. sieversii demonstrated the highest sensitivity to zinc deficiency.
Asunto(s)
Malus/fisiología , Raíces de Plantas/fisiología , Zinc/fisiología , Biomasa , Hojas de la Planta/químicaRESUMEN
In apple cultivation, simulation models may be used to monitor fruit size during the growth and development process to predict production levels and to optimize fruit quality. Here, Fuji apples cultivated in spindle-type systems were used as the model crop. Apple size was measured during the growing period at an interval of about 20 days after full bloom, with three weather stations being used to collect orchard temperature and solar radiation data at different sites. Furthermore, a 2-year dataset (2011 and 2012) of apple fruit size measurements were integrated according to the weather station deployment sites, in addition to the top two most important environment factors, thermal and sunshine hours, into the model. The apple fruit diameter and length were simulated using physiological development time (PDT), an indicator that combines important environment factors, such as temperature and photoperiod, as the driving variable. Compared to the model of calendar-based development time (CDT), an indicator counting the days that elapse after full bloom, we confirmed that the PDT model improved the estimation accuracy to within 0.2 cm for fruit diameter and 0.1 cm for fruit length in independent years using a similar data collection method in 2013. The PDT model was implemented to realize a web-based management information system for a digital orchard, and the digital system had been applied in Shandong Province, China since 2013. This system may be used to compute the dynamic curve of apple fruit size based on data obtained from a nearby weather station. This system may provide an important decision support for farmers using the website and short message service to optimize crop production and, hence, economic benefit.
Asunto(s)
Frutas/crecimiento & desarrollo , Frutas/efectos de la radiación , Malus/crecimiento & desarrollo , Malus/efectos de la radiación , Sistemas de Información Administrativa , Luz Solar , Temperatura , Teléfono Celular , Internet , Modelos Estadísticos , Factores de TiempoRESUMEN
AIM: The aim of this study was to investigate whether neighborhood safety as perceived by primary caregivers is associated with asthma morbidity outcomes among inner-city school children with asthma. METHODS: School children with asthma were recruited from 25 inner-city schools between 2009 and 2012 for the School Inner-City Asthma Study (N = 219). Primary caregivers completed a baseline questionnaire detailing their perception of neighborhood safety and their children's asthma symptoms, and the children performed baseline pulmonary function tests. In this cross-sectional analysis, asthma control was compared between children whose caregivers perceived their neighborhood to be unsafe versus safe. RESULTS: After adjusting for potential confounders, those children whose primary caregivers perceived the neighborhood to be unsafe had twice the odds of having poorly controlled asthma (odds ratio [OR] adjusted = 2.2, 95% confidence interval [CI] = 1.2-3.9, P = 0.009), four times the odds of dyspnea and rescue medication use (OR adjusted = 4.7; 95% CI = 1.7-13.0, P = 0.003, OR adjusted = 4.0; 95% CI = 1.8-8.8, P < 0.001, respectively), three times as much limitation in activity (OR adjusted = 3.2; 95% CI = 1.4-7.7, P = 0.008), and more than twice the odds of night-time symptoms (OR adjusted = 2.2; 95% CI = 1.3-4.0, P = 0.007) compared to participants living in safe neighborhoods. There was no difference in pulmonary function test results between the two groups. CONCLUSIONS: Primary caregivers' perception of neighborhood safety is associated with childhood asthma morbidity among inner-city school children with asthma. Further study is needed to elucidate mechanisms behind this association, and future intervention studies to address social disadvantage may be important.
Asunto(s)
Asma/epidemiología , Características de la Residencia , Seguridad , Población Urbana , Niño , Estudios Transversales , Disnea/epidemiología , Femenino , Disparidades en el Estado de Salud , Humanos , Masculino , Estudios Prospectivos , Estados UnidosRESUMEN
BACKGROUND: Children with asthma have increased prevalence of food allergies. The relationship between food allergy and asthma morbidity is unclear. OBJECTIVE: We aimed to investigate the presence of food allergy as an independent risk factor for increased asthma morbidity by using the School Inner-City Asthma Study, a prospective study that evaluates risk factors and asthma morbidity among urban children. METHODS: We prospectively surveyed, from inner-city schools, 300 children with physician-diagnosed asthma, followed by clinical evaluation. Food allergies were reported, which included symptoms experienced within 1 hour of food ingestion. Asthma morbidity, pulmonary function, and resource utilization were compared between children with food allergies and those without. RESULTS: Seventy-three of 300 children with asthma (24%) surveyed had physician-diagnosed food allergy, and 36 (12%) had multiple food allergies. Those with any food allergy independently had increased risk of hospitalization (OR [odds ratio] 2.35 [95% CI, 1.30-4.24]; P = .005) and use of controller medication (OR 1.99 [95% CI, 1.06-3.74]; P = .03). Those with multiple food allergies also had an independently higher risk of hospitalization in the past year (OR 4.10 [95% CI, 1.47-11.45]; P = .007), asthma-related hospitalization (OR 3.52 [95% CI, 1.12-11.03]; P = .03), controller medication use (OR 2.38 [95% CI, 1.00-5.66]; P = .05), and more provider visits (median, 4.5 vs 3.0; P = .008). Furthermore, lung function was significantly lower (percent predicted FEV1 and FEV1/FVC ratios) in both food allergy category groups. CONCLUSIONS: Food allergy is highly prevalent in inner-city school-aged children with asthma. Children with food allergies have increased asthma morbidity and health resource utilization with decreased lung function, and this association is stronger in those with multiple food allergies.