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1.
Nanotechnology ; 33(49)2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36067708

ABSTRACT

Materials exhibiting an exchange bias effect are a class of magnetic systems that have a wide range of possible technological applications e.g. in sensors, read heads, and spintronic devices. In this study, we demonstrate the effect of laser interference patterning on the magnetic properties of Pd/CoO/Co/Pd multilayers. Laser patterning creates arrays of well-ordered stripes, rectangles, and squares on the substrate surface. We found that the laser treatment caused magnetic softening of the structure edges while the centers of the objects remained unchanged and exhibited the exchange bias effect. In this study we focused on the shape and configurational magnetic anisotropies induced by patterning and showed that the magnetic properties varied depending on the angle at which the external magnetic field was applied with respect to the pattern geometry.

2.
Nanotechnology ; 28(19): 194003, 2017 May 12.
Article in English | MEDLINE | ID: mdl-28332486

ABSTRACT

In this work, we propose a new method for the large-scale production of flexible, periodic alumina arrays with well-ordered pores. We show the incorporation of pre-patterning based on polystyrene (PS) nanosphere lithography into an aluminium anodization process. We prepared ordered monolayers of PS spheres with average diameters of (510 ± 10) nm and (430 ± 10) nm on a large area (1.5 × 1.5 cm2) of the Si substrate. Next, we deposited a 5 µm aluminium layer on arrays of PS nanospheres using the sputtering technique. After the deposition, we covered the aluminium film with a polymer Scotch adhesive tape, and separated it from the silicon substrate by ultrasonic-assisted lift-off. Finally, we performed the anodization of the aluminium. We compared the pore and cell sizes, and the pore distance for the templates obtained by this technique, with reference to the templates prepared by a two-step anodization process. Using this new approach, we obtained highly ordered hexagonal 2D lattices over a large area of up to 2 cm2 with sparse defects, amounting to not more than four defects per 1000 µm2 on average. Here, we show that the use of indentation techniques is not necessary and can be replaced by a fast, cheap and easy pre-patterning step based on nanosphere lithography.

3.
Nanotechnology ; 26(42): 425301, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26422608

ABSTRACT

Ordered FePdCu nanoisland arrays were formed by annealing at 600 °C, which caused solid state dewetting of [Cu/Fe/Pd] multilayers deposited on self-assembled SiO2 nanospheres with a size of 100 nm. A single FePdCu island was formed on the top of each SiO2 nanosphere. The structure of the obtained system was studied by x-ray diffraction (XRD), while its magnetic properties were studied by SQUID magnetometry. A partially ordered L10 alloy appeared in the annealed films, leading to magnetic hardening of the material. The paper presents the influence of the patterning on the system properties. It is shown that templated dewetting is a method providing nanoislands with well-controlled sizes and positions. The role of copper admixture in controlling the structural and magnetic properties is also discussed.

4.
Clin Exp Allergy ; 45(1): 146-53, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25323476

ABSTRACT

BACKGROUND: The large increase in asthma prevalence continues in several, but not all areas. Despite the individual risk factors that have been identified, the reasons for the observed trends in prevalence are largely unknown. OBJECTIVE: This study sought to characterize what trends in risk factors accompanied trends in asthma prevalence. METHODS: Two population-based cohorts of 7- to 8-year-old children from the same Swedish study areas examined by expanded International Study of Asthma and Allergy in Childhood questionnaires were compared 10 years apart. In 1996 and 2006, 3430 (97% participation) and 2585 (96% participation) questionnaires were completed, respectively. A subset was skin-prick-tested: in 1996 and 2006, 2148 (88% participation) and 1700 (90% participation) children, respectively. The adjusted population-attributable fraction (aPAF) was calculated using the prevalence and multivariate odds ratio of each risk factor. RESULTS: The prevalence of current asthma and wheeze was similar in 1996 and 2006. Allergic sensitization, however, increased from 21% to 30%. The prevalence of parental asthma increased from 17% to 24%, while respiratory infections and maternal smoking decreased (60% to 29% and 32% to 16%, respectively). The aPAFs of non-environmental risk factors for current asthma increased in 1996-2006: allergic sensitization from 35% to 41%, parental asthma from 27% to 45% and male sex from 20% to 25%. Conversely, the aPAFs of environmental risk factors decreased: respiratory infections from 36% to 32% and damp home and maternal smoking from 14% and 19%, respectively, to near zero in 2006. CONCLUSIONS AND CLINICAL RELEVANCE: From 1996 to 2006, the non-environmental risk factors parental asthma, allergic sensitization and male sex had an increasing or constant importance for current asthma in 7- to 8-year-old children. The importance of the environmental exposures damp home, respiratory infections and maternal smoking decreased. This counterbalancing in risk factors may explain the level of prevalence of current asthma.


Subject(s)
Asthma/epidemiology , Environmental Exposure/adverse effects , Surveys and Questionnaires , Asthma/etiology , Cetrimonium Compounds , Child , Drug Combinations , Female , Humans , Male , Myristates , Nicotinic Acids , Retrospective Studies , Risk Factors , Sex Factors , Simethicone , Stearic Acids , Sweden/epidemiology
5.
Clin Exp Allergy ; 42(12): 1765-71, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23181792

ABSTRACT

BACKGROUND: Previous studies have suggested an association between allergy and mood and anxiety disorders. Yet, extant work suffers from methodological limitations. OBJECTIVE: To investigate the association between physician-diagnosed allergy and DSM-IV mood and anxiety disorders in the general population, and to examine the role of allergy treatment in this relationship. METHODS: Data were drawn from the German National Health Interview and Examination Survey, a population-based, representative sample of 4,181 adults aged 18-65 in Germany. Allergy was diagnosed by physicians during medical examination and mental disorders were diagnosed using the CIDI. RESULTS: Allergy was associated with an increased prevalence of any anxiety disorder [OR = 1.3 (1.1, 1.6)], panic attacks [OR = 1.6 (1.1, 2.1)], panic disorder [OR = 1.6 (1.01, 2.3)], GAD [OR = 1.8 (1.1, 3.0)], any mood disorder [OR = 1.4 (1.1, 1.7)], depression [OR = 1.4 (1.1, 1.7)] and bipolar disorder [OR = 2.0, (1.0, 3.8)]. After adjusting for desensitization treatment status, these relationships were no longer significant. Those treated for allergy were significantly less likely to have any mood or anxiety disorder [OR = 0.65 (0.4, 0.96)], compared to those untreated. All relationships were adjusted for age, gender and socioeconomic status (SES). CONCLUSIONS & CLINICAL RELEVANCE: These findings provide the first evidence of a link between physician-diagnosed allergy and DSM-IV mood and anxiety disorders in a representative sample. Treatment for allergy may mitigate much of this relationship.


Subject(s)
Anxiety Disorders/epidemiology , Hypersensitivity/drug therapy , Mood Disorders/epidemiology , Adolescent , Adult , Aged , Anxiety Disorders/diagnosis , Comorbidity , Depressive Disorder/diagnosis , Depressive Disorder/epidemiology , Diagnostic and Statistical Manual of Mental Disorders , Female , Germany/epidemiology , Health Surveys , Humans , Hypersensitivity/diagnosis , Hypersensitivity/epidemiology , Male , Middle Aged , Mood Disorders/diagnosis , Population Surveillance , Prevalence , Young Adult
7.
J Physiol Pharmacol ; 62(2): 189-95, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21673367

ABSTRACT

UNLABELLED: One of the mechanisms supposed to explain the increasing prevalence of asthma, among children in particular, is the use of antibiotics because they may modify natural microbial exposure and development of the immune system in early childhood. The aim of this study is to investigate the association between the use of various classes of antibiotics (penicillin, cephalosporin and macrolide derivatives) in early childhood and the medical diagnosis of asthma or wheezing reported by mothers over the follow-up after adjustment for potential confounders and respiratory infections. In a population-based sample of 5-year-olds, a part of the ongoing birth cohort study, the standardized interviews on health outcomes, potential confounders (child's gender, maternal atopy, parity, prenatal and postnatal environmental tobacco smoke) and the use of antibiotics were gathered from mothers of 310 children. While the overall use of antibiotics during the early childhood was insignificantly associated with asthma (adjusted OR = 1.65, 95%CI: 0.93 - 2.93), the risk estimates were significant both for macrolide antibiotics (adjusted OR=2.14, 95%CI: 1.16-3.95) and cephalosporins (OR=1.98, 95%CI: 1.14-3.37). The significant excess in IRR (incident risk ratio) of wheezing episodes was related only to the use of macrolide antibiotics (adjusted IRR=1.91, 95%CI: 1.12-3.27). The use of other classes of antibiotics was found not to be associated with the medical diagnosis of asthma or wheezing episodes recorded in the study period. CONCLUSION: as early childhood use of broad spectrum antibiotics is associated with an increased risk of developing asthma in 5-year-olds, it may be hypothesized that the antibiotic- related suppression of allergic inflammatory responses in the course of treatment may later lead to greater than before atopic immune response in Th2 children or an impairment of Th1 immune responses in early childhood.


Subject(s)
Anti-Bacterial Agents/adverse effects , Asthma/chemically induced , Asthma/epidemiology , Drug Hypersensitivity/epidemiology , Pharmacoepidemiology/methods , Respiratory Sounds/etiology , Adolescent , Adult , Age Factors , Asthma/immunology , Child, Preschool , Cohort Studies , Drug Hypersensitivity/immunology , Female , Follow-Up Studies , Humans , Male , Pregnancy , Prospective Studies , Respiratory Sounds/immunology , Young Adult
9.
Indoor Air ; 19(3): 193-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19220508

ABSTRACT

UNLABELLED: In New York (NY), Latinos often have greater asthma morbidity than other ethnicities, and dust-mite sensitization is common despite low allergen levels. We investigated mite allergen exposure and sensitization in atopic and/or asthmatic women, the majority being Puerto Rican. Women (n = 274) recruited for a birth cohort study were visited postnatally. Dust from their homes was analyzed for mite allergens (Der f 1, Der p 1, and Blo t 5). Serum was analyzed for total and allergen-specific IgE. Thirty-seven percent were sensitized to Dermatophagoides pteronyssinus, 34% to Dermatophagoides farinae, and 21% to Blomia tropicalis. Only 5% of NY homes had levels of Der f 1 >2 microg/g; none had Blo t 5 or Der p 1 above this level. Caribbean or Latin American birthplace (a proxy for childhood exposure) was not associated with mite sensitization. Sensitization to D. pteronyssinus and D. farinae was associated with a report of doctor-diagnosed asthma [Odds ratio (OR) = 3.27, P = 0.003; OR = 2.81, P = 0.010, respectively]; sensitization to any mite was associated with asthma medication use in the past 12 months (OR = 3.12, P = 0.004). These associations held even after adjustment for cockroach, mouse, and cat sensitization. PRACTICAL IMPLICATIONS: Despite the low concentrations of mite allergen in our community, many of the women in the atopically enriched cohort were sensitized to mites, even Blomia tropicalis which is typically found only in tropical environments.


Subject(s)
Antigens, Dermatophagoides/analysis , Asthma/epidemiology , Pyroglyphidae/immunology , Adult , Animals , Antibody Specificity , Asthma/etiology , Asthma/immunology , Cats , Cohort Studies , Female , Hispanic or Latino , Humans , Immunoglobulin E/blood , Mice , New York City/epidemiology , Young Adult
10.
J Epidemiol Community Health ; 62(7): 647-9, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18450765

ABSTRACT

BACKGROUND: The prevalence of childhood asthma in the USA increased by 50% from 1980 to 2000, with especially high prevalence in poor urban communities. METHODS: Data on the prevalence of asthma among children aged 4-5 years and on hospitalisations for asthma among children less than 15 years old were available for 42 health service catchment areas within New York City. Street tree counts were provided by the New York City Department of Parks and Recreation. The proximity to pollution sources, sociodemographic characteristics and population density for each area were also measured. RESULTS: Controlling for potential confounders, an increase in tree density of 1 standard deviation (SD, 343 trees/km(2)) was associated with a lower prevalence of asthma (RR, 0.71 per SD of tree density; 95% CI, 0.64 to 0.79), but not with hospitalisations for asthma (RR, 0.89 per SD of tree density; 95% CI, 0.75 to 1.06). CONCLUSIONS: Street trees were associated with a lower prevalence of early childhood asthma. This study does not permit inference that trees are causally related to asthma at the individual level. The PlaNYC sustainability initiative, which includes a commitment to plant one million trees by the year 2017, offers an opportunity for a large prospective evaluation.


Subject(s)
Asthma/epidemiology , Hospitalization/statistics & numerical data , Trees , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Humans , Infant , Infant, Newborn , New York City/epidemiology , Prevalence , Residence Characteristics , Risk Factors , Urban Health
11.
Clin Exp Allergy ; 38(6): 968-76, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18355370

ABSTRACT

BACKGROUND: In past research, children with older siblings were more likely than others to wheeze at age 2 years, but less likely by age 6 years. Higher infection transmission and a down-regulated allergic immune response as a result of these infections, respectively, were suggested as the causes. However, in a study of children aged 0-3 years in a low-income urban community in New York City, USA, with high asthma prevalence, we observed no birth-order effect. OBJECTIVE: To evaluate the association between birth order and atopy and respiratory symptoms in 4-year-old children attending Head Start programs in NYC. METHODS: Respiratory symptoms were assessed by questionnaire for 1005 children (mean age 4.0 years) living in high asthma prevalence neighbourhoods. Serum was collected from a subgroup of the children (n=494) and specific IgE responses to dust mite, cockroach, mouse, and cat allergens were measured. RESULTS: Prevalence of specific IgE (> or =0.35 IU/mL) did not differ significantly among first (35%), second (35%), and later-born children (28%) (P=0.23). Increasing birth order was associated with increasing prevalence of respiratory symptoms in the prior year, including wheeze (first 20%, second 27%, third or later 35%; P<0.001), being awakened at night by cough (28%, 33%, 38%; P=0.005), emergency department visits (14%, 17%, 21%; P=0.02) and hospitalizations for difficulty breathing (6.1%, 6.6%, 10%; P=0.04). The associations of birth order with respiratory symptoms were statistically significant only for the non-seroatopic children and those without an asthmatic parent. CONCLUSIONS: Non-seroatopic children with older siblings were more likely than those without older siblings to have respiratory symptoms at age 4 years. Although the stability of these associations over time remains to be determined, the differences in findings between this study and our previous NYC birth cohort study suggest that patterns of asthma development may vary even among low-income populations within the same city.


Subject(s)
Asthma/epidemiology , Birth Order , Rhinitis, Allergic, Seasonal/epidemiology , Allergens/immunology , Animals , Asthma/blood , Asthma/pathology , Cats , Child, Preschool , Cohort Studies , Family Characteristics , Female , Hospitalization/statistics & numerical data , Humans , Immunoglobulin E/blood , Logistic Models , Male , Mice , Multivariate Analysis , New York City/epidemiology , Otitis Media/epidemiology , Poverty , Prevalence , Rhinitis, Allergic, Seasonal/blood , Rhinitis, Allergic, Seasonal/pathology , Risk Factors , Sex Factors , Siblings , Surveys and Questionnaires , Urban Population
12.
Clin Respir J ; 2 Suppl 1: 26-33, 2008 Oct.
Article in English | MEDLINE | ID: mdl-20298347

ABSTRACT

BACKGROUND: Prospective studies of asthma and allergic conditions based on the general population are scarce. AIM: To summarize the methods and main results from a prospective study among school children. METHODS: In 1996, a cohort of 3525 children aged 7/8 years in Northern Sweden were invited to a questionnaire survey using an expanded ISAAC protocol, and 97% participated. The cohort has been followed up yearly with high participation rate. Skin prick tests were conducted 1996, 2000 and 2006/2007. Allergens in dust from homes and schools have been analyzed. Sub samples have participated in interviews, lung function tests, bronchial hyper reactivity test, and analyses of IgE and IgG antibodies in serum. RESULTS: The prevalence of asthma was 6% at age 7-8 years and increased by age. The incidence of physician-diagnosed asthma after the age of 7-8 years was around 1/100/year. The prevalence of positive skin prick test increased from 21% at age 7-8 to 30% at age 11-12 years. Remission of allergic sensitization was rare, while asthma remission was 5% yearly. The main risk factor for asthma and allergic sensitization increased in importance with increasing age. Allergic and non-allergic asthma had different risk factor pattern. Environmental risk factors decreased in impact after the age of 7. Avoidance of pets at home did not protect from asthma or allergic sensitization. CONCLUSION: The study includes important sources of data for further longitudinal analyses that will contribute to the understanding of the development and the nature of asthma and allergic sensitization.


Subject(s)
Asthma/epidemiology , Hypersensitivity/epidemiology , Pulmonary Disease, Chronic Obstructive/epidemiology , Adolescent , Asthma/diagnosis , Child , Female , Humans , Hypersensitivity/diagnosis , Incidence , Longitudinal Studies , Male , Prevalence , Prospective Studies , Pulmonary Disease, Chronic Obstructive/diagnosis , Remission, Spontaneous , Reproducibility of Results , Risk Factors , Sensitivity and Specificity , Skin Tests , Surveys and Questionnaires/standards , Sweden/epidemiology
13.
Allergy ; 63(1): 87-94, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18053018

ABSTRACT

BACKGROUND: Striking differences in asthma prevalence have been reported among Hispanic adults and children living in different cities of the USA. Prevalence is highest among those of Puerto Rican and lowest among those of Mexican origin. We hypothesized that body size would mediate this association. METHODS: Parents of children in New York City Head Start programs completed a questionnaire including demographic factors, health history, a detailed history of respiratory conditions, lifestyle, and home environment. Children's height and weight were measured in home visits. Logistic regression was used to model the association of asthma with body mass index percentile (<85th percentile, gender/age specific vs>or=85th percentile, gender/age specific), national origin, and other factors. RESULTS: Of 517 children at mean age of 4.0 +/- 0.6 years, 34% met the study criteria for asthma, and 43% were above the 85th percentile. Asthma was strongly associated with non-Mexican national origin, male gender, allergy symptoms, and maternal asthma, and marginally with body size. The odds of asthma among boys of non-Mexican origin was 5.9 times that among boys of Mexican origin [95% confidence interval (CI): 2.9-12.2]; the comparable odds ratio (OR) among girls was 1.8 (95% CI: 0.9-3.6). Body mass was associated with asthma among girls [OR = 2.0 (95% CI: 1.1-3.7)], but not boys [OR = 1.4 (95% CI: 0.8-2.6)]. CONCLUSIONS: The association of asthma with both body mass and national origin was gender-specific among the children in our study. Ours is one of the first studies to report on pediatric asthma in different Hispanic populations in the same city, by gender.


Subject(s)
Asthma/diagnosis , Asthma/ethnology , Body Mass Index , Hispanic or Latino/statistics & numerical data , Age Distribution , Asthma/immunology , Child, Preschool , Cohort Studies , Confidence Intervals , Female , Humans , Incidence , Logistic Models , Male , Mexican Americans/statistics & numerical data , New York City/epidemiology , Odds Ratio , Risk Factors , Severity of Illness Index , Sex Factors , Surveys and Questionnaires , Urban Population
14.
Allergy ; 61(5): 549-55, 2006 May.
Article in English | MEDLINE | ID: mdl-16629783

ABSTRACT

BACKGROUND: Childhood is the most important time for asthma development. The aims of this study were to study changes in prevalence of asthma and wheeze, remission of asthma and changes in risk factor pattern from age 7-8 to age 11-12 in a cohort of school children. METHODS: In 1996, 3525 children aged 7-8 years in northern Sweden were invited to participate in a parental expanded ISAAC questionnaire survey. The cohort has been followed prospectively with yearly follow-ups to age 11-12, with a 97% yearly response rate. Skin prick tests were conducted at age 7-8 and 11-12. RESULTS: The prevalence of physician-diagnosed asthma increased from 5.7% at age 7-8 to 7.7% at age 11-12. Life-time prevalence of wheeze was 34.7% at age 11-12. The remission of asthma was 10% yearly and inversely related to allergic sensitization. Relapses were common, and remission persisting throughout the observation period was 5% yearly. Allergic sensitization was associated with current asthma at age 7-8 [adjusted odds ratio (OR) 4.9 (95% confidence interval (CI) 3.3-7.3)] and when the children were 4 years older [OR 5.6 (3.9-8.2)]. A family history of asthma was associated with current asthma at age 7-8 [OR 3.0 (2.1-4.5)] and 11-12 (OR 2.8 [2.0-3.9]). Ever having lived with a cat was significantly negatively associated with current asthma. CONCLUSIONS: The prevalence of asthma increased continuously during the primary school ages. Among several significant risk factors, allergic sensitization and a family history of asthma were the most important. With increasing age many known risk factors lost significance. Remission was inversely related to allergic sensitization.


Subject(s)
Asthma/epidemiology , Hypersensitivity/epidemiology , Age Distribution , Child , Cohort Studies , Comorbidity , Female , Humans , Longitudinal Studies , Male , Odds Ratio , Prevalence , Prospective Studies , Recurrence , Remission, Spontaneous , Respiratory Sounds/immunology , Risk Factors , Skin Tests , Surveys and Questionnaires , Sweden/epidemiology
15.
Indoor Air ; 15(4): 228-34, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15982269

ABSTRACT

UNLABELLED: Considering that high school students spend a large proportion of their waking hours in the school environment, this could be an important location for exposure to indoor allergens. We have investigated the levels of mouse and cockroach allergens in the settled dust and air from 11 schools in a major northeastern US city. Settled dust samples were vacuumed from 87 classrooms, three times throughout the school year. Two separate air samples (flow = 2.5 lpm) were collected by 53 students over a 5-day period from both their school and their home. Mouse allergen (MUP) in the dust varied greatly between schools with geometric means ranging from 0.21 to 133 microg/g. Mouse allergen was detectable in 81% of the samples collected. Cockroach allergen (Bla g 2) ranged from below limit of detection (<0.003 microg/g) to 1.1 microg/g. Cockroach allergen was detected (>0.003 microg/g) in 71% of the dust samples. Bla g 2 was detected in 22% of airborne samples from the schools. By comparison, mouse allergen was only detected in 5%. These results indicate that the school may be an important location for exposure to allergens from mice and cockroaches and is an indoor environment that should be considered in an overall allergen intervention strategy. PRACTICAL IMPLICATIONS: To date, cockroach and mouse allergen intervention strategies have been mainly focused on the home environment. Considering that children spend a significant amount of time in schools, some studies have assessed cockroach allergen levels in schools. This study provides a clearer picture of the distribution and variability of not only cockroach allergen, but also mouse allergen in the school environment. In addition, this study describes limitations of personal air sampling in a student population. Our results suggest that although cockroach and mouse allergens are commonly recovered in classroom dust samples of inner city schools, cockroach allergens are recovered in the personal air samples with a greater frequency relative to mouse allergens.


Subject(s)
Air Pollution, Indoor/analysis , Allergens/analysis , Dust , Environmental Exposure , Schools , Adolescent , Animals , Cities , Cockroaches/immunology , Environmental Monitoring , Humans , Mice/immunology , New England , Urban Population
16.
Allergy ; 60(7): 965-8, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15932390

ABSTRACT

BACKGROUND: Several epidemiology studies have found an increase in the major cockroach allergen Bla g 2 with reported pesticide use. AIMS OF THE STUDY: Our aim was to investigate the effect on the excretion of Bla g 1 and Bla g 2 allergens by cockroaches exposed to sub-lethal doses of the pesticides, boric acid and hydramethylnon gel. METHODS: German cockroaches in separate colonies were fed either boric acid or hydramethylnon gel at concentrations of 0.2, 0.1 and 0.01% in their water supply over a 2 week period. Ten colonies were exposed to each treatment concentration. Bla g 1 and Bla g 2 in fecal pellets were measured by ELISA. RESULTS: Cockroaches exposed to boric acid excreted fecal pellets with significantly higher concentrations of Bla g 2 (35,400 U/g) than did controls (12,700 U/g) (P = 0.001). Bla g 1 concentrations were not significantly different. There was no difference in either Bla g 1 or Bla g 2 concentrations between cockroaches that ingested hydramethylnon gel and those in the controls colonies. CONCLUSIONS: The application of boric acid, a common pesticide, appears to paradoxically increase the production of Bla g 2, a major allergen, by the surviving cockroaches. This may have important implications in avoidance strategies.


Subject(s)
Aspartic Acid Endopeptidases/immunology , Boric Acids/pharmacology , Cockroaches/immunology , Insecticides/pharmacology , Animals , Cockroaches/drug effects
17.
Respir Med ; 96(12): 1006-13, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12477216

ABSTRACT

Studies of incidence of asthma are still limited. A longitudinal study of asthma in school children was started in 1996 in Northern Sweden. The incidence of asthma and the associated risk factors have been studied over a 2 years period. The study started with a parental questionnaire, the ISAAC questionnaire with additional questions, and a skin-prick test. The cohort, 3,525 children, 7 and 8 years old at start, was followed after 1 and 2 years by using the same questions, Each year responded 97%. The cumulative incidence of physician-diagnosed asthma was 1.7%, 0.9/1,000/year the first year, and 0.8/1,000/year the second year. The cumulative incidence of wheezing was 6.3%, and of frequent or daily users of asthma medicines 2.1%. Significant risk factors for incident asthma were a positive skin test, OR 5.64 (3.10-10.25); rhinitis,OR 3.53 (1.80-6.90); eczema, OR 2.19 (1.26-3.82); a family history of asthma, OR 2.83 (1.75-4.56); low birth weight, OR 3.38 (1.61-754); respiratory infections, OR 2.12 (1.24-3.63); male gender, OR 1.71 (1.06-2.81); and a smoking mother OR 2.00 (1.07-3.73). In summary the incidence of asthma during 2 years after age 7 was high, almost 1/100/year. Allergy was the most important risk factor, but other factors were influential.


Subject(s)
Asthma/epidemiology , Animals , Animals, Domestic , Asthma/etiology , Asthma/immunology , Cats , Child , Dogs , Female , Follow-Up Studies , Humans , Hypersensitivity/complications , Hypersensitivity/diagnosis , Incidence , Male , Multivariate Analysis , Prevalence , Prospective Studies , Respiratory Sounds , Respiratory Tract Infections/complications , Risk Factors , Sex Factors , Skin Tests , Smoking/adverse effects , Sweden/epidemiology
19.
Pediatrics ; 108(6): E97, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11731624

ABSTRACT

OBJECTIVE: The increase in asthma prevalence has been documented worldwide, affecting many races living in many different climates. Multiple studies have demonstrated that the most striking prevalence and morbidity of asthma in the United States has been in black children, but little research has determined the scale of the increase, or specifically when the disease became severe in this group. This study sought to determine exactly when the rise in asthma hospitalizations among black patients began and what the pattern of asthma hospitalizations has been in different races and age groups over a 40-year period in 1 urban area. METHODS: A retrospective chart review of discharges from the Medical University of South Carolina was conducted from 1956 to 1997. Charts with the primary discharge diagnosis of asthma were examined for discharge date, race, and age group (0- to 4-year-olds, 5- to 18-year-olds, 19- to 50-year-olds, > or =51-year-olds). The diagnostic codes used were based on the International Classification of Diseases (ICD)-6, 1956-1957; ICD-7, 1958-1967; ICD-8, 1968-1978; and ICD-9, 1979-1997. Over the period studied, this hospital was the primary inpatient provider for children in this area, and the only provider for uninsured children. Between 1960 and 1990, the racial makeup of the area remained stable, as did the percentage of blacks living at the poverty level. The raw number of asthma discharges, rate per 10 000 discharges of the same race, and rate per 100 000 population in Charleston County were tabulated for each age group and racial category. RESULTS: Over the time period examined, there has been a progressive increase in asthma hospitalizations in black individuals of all age groups and in whites under 18 years. The most striking increase has been in black children 0 to 18 years old (figure). The increase either as raw values or as a rate per 100 000 began around 1970, and was linear. This increase in black children discharged with asthma as a rate per 100 000 population was 20-fold: the rate increased from 18 in 1970 to 370 in 1997. Asthma discharges as a rate per 10 000 black children discharged increased by 24-fold from 1960 to 1997. Total discharges from the hospital increased from 49 000 to 128 000 per year over this period. Blacks made up only 28% of discharges in 1957, but that proportion increased to 56% in 1960 and remained relatively stable over the following 35 years. The increase seen in white children 0 to 18 years of age as a rate per 100 000 population was 5-fold and began around 1980. Both increases seem to be consistent over the time period studied, and continued to 1997. [figure: see text]. CONCLUSIONS: Among a predominantly poor black population living in a southern US city, there has been a steady increase in childhood asthma hospitalizations over the past 30 years. A significant although less dramatic rise has occurred in white children. Over this time period, although there have been many changes in lifestyle that could have contributed to this rise, there have been no major changes in housing conditions for poor patients. In addition, Medicaid coverage for children in South Carolina did not change significantly until 1999. The time course of these increases parallels increases reported in other Western populations, suggesting that there must be 1 or more common factors contributing to the rise. Many explanations have been offered for the changes in incidence and severity of asthma. The scale of the change, time course, and linearity of the increase in this study represent a challenge to many of the hypotheses proposed to explain this epidemic.


Subject(s)
Asthma/epidemiology , Black or African American/statistics & numerical data , Hospitalization/statistics & numerical data , Adolescent , Adult , Asthma/ethnology , Asthma/therapy , Child , Child, Preschool , Humans , Infant , Middle Aged , Prevalence , Retrospective Studies , Socioeconomic Factors , South Carolina/epidemiology , Urban Population , White People/statistics & numerical data
20.
Clin Exp Allergy ; 31(12): 1891-5, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11737041

ABSTRACT

BACKGROUND: Sensitization to Alternaria alternata is a risk factor for the development of wheezing and asthma. Alt a 1 is the major Alternaria allergen causing sensitization in asthmatics. Some atopic dermatitis (AD) patients have very high immunoglobulin (Ig)E antibody (ab) to Alternaria as analysed by Pharmacia CAP, however, it is not clear whether these are specific responses or whether Alt a 1 is involved in disease symptoms. OBJECTIVE: The aim of this study was to analyse specific IgE and IgG ab responses to recombinant Alt a 1 in asthmatic and AD patients and to compare these results to IgE ab against Alternaria measured by CAP. METHODS: Sera from individuals who were IgE positive to Alternaria by CAP were obtained from 58 patients with asthma/rhinitis, 19 patients with AD, and 20 patients with cystic fibrosis (CF) who were included as specificity controls. IgE and IgG ab to recombinant Alt a 1 were measured by radioimmunoassay (RIA). RESULTS: Of 43 asthma/rhinitis patients having an Alternaria CAP score > 2, a high percentage (93%) had both IgE and IgG ab to Alt a 1, emphasizing its importance as a major allergen. Only, 47% of AD patients with CAP score greater than 2 had ab to Alt a 1, and their levels were low when compared to the asthmatics. For CF controls, 75% of these patients had no IgE ab to Alt a 1, and those which were positive to Alt a 1 by RIA were also positive by CAP. Overall, patients with a low CAP (1-2) had a low prevalence (20-30%) of IgE or IgG ab to Alt a 1. CONCLUSION: IgE and IgG ab to Alt a 1 in asthmatics are good markers for sensitization to Alternaria. Although AD patients gave high Alternaria CAP scores, they had low or undetectable levels of IgE to Alt a 1, suggesting that other Alternaria allergens may be important in AD or that the CAP results are non-specific. Recombinant allergens may provide more specific measures of sensitization to fungi.


Subject(s)
Alternaria/immunology , Asthma/immunology , Hypersensitivity, Immediate/immunology , Immunoglobulin E/immunology , Immunoglobulin G/immunology , Allergens/adverse effects , Allergens/immunology , Antibodies, Fungal/immunology , Antibody Formation , Antibody Specificity/immunology , Asthma/blood , Asthma/diagnosis , Biomarkers/blood , Boston/epidemiology , Enzyme-Linked Immunosorbent Assay , Humans , Hypersensitivity, Immediate/blood , Hypersensitivity, Immediate/diagnosis , Immunization , Immunoglobulin E/blood , Immunoglobulin G/blood , Prevalence , Proteins/analysis , Proteins/immunology , RNA, Long Noncoding , Transferases , Tumor Suppressor Proteins , Virginia/epidemiology
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