bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age effects on consumer demand: an additive partially linear regression model
Authors: Lyssiotou Panayiota , Pashardes Panos , Stengos Thanasis 
Published: March 2003

An additive partially linear regression model is used to estimate non‐parametrically the effects of total expenditure and age in the context of Engel curves and to investigate the specification and welfare interpretation of the age effects in parametric models of consumer behaviour. Empirical analysis based on data drawn from the U.K. Family Expenditure Survey shows that modelling of the effects of age requires a more sophisticated approach than that generally adopted in parametric demand analysis. It also shows that failing to adequately capture these effects can have misleading welfare implications. JEL Classification: C14, D12 L’effet de l’âge sur la demande des consommateurs : un modèle de régression additif partiellement linéaire. On utilise un modèle de régression additif partiellement linéaire pour faire la calibration non paramétrique des effets de la dépense totale et de l’âge dans le contexte de courbes de Engel, et pour enquêter sur la spécification des effets d’âge et leur interprétation en termes de bien‐être dans des modèles paramétriques de comportements du consommateur. L’analyse empirique est construite sur des données de la U.K. Family Expenditures Survey et montre que la modélisation des effets de l’âge réclame une approche plus sophistiquée que celle qui est généralement utilisée dans l’analyse paramétrique de la demande. On montre aussi que le manque à bien saisir ces effets peut conduire à des conclusions fausses pour ce qui est du niveau de bien‐être.
The Performance of Internet Firms Following Their Initial Public Offering
Authors: Johnston Jarrod , Madura Jeff 
Published: March 2003

We find that initial returns were more favorable for Internet initial public offerings (IPOs) than non–Internet firm IPOs. Since the demise of the Internet sector, the underpricing of Internet–firm IPOs is not significantly different from other IPOs.Initial returns of Internet firms are positively and significantly related to underwriter prestige and to pre–IPO market conditions. However, initial returns after the demise of the Internet sector are not significantly related to these characteristics.The aftermarket performance of Internet firms is initially favorable but weakens over time. Firms that experienced higher initial returns during the strong Internet cycle experience weaker aftermarket performance.
Association of heparin‐induced skin lesions, intracutaneous tests, and heparin‐induced IgG
Authors: Harenberg J , Huhle G , Wang L , Hoffmann U , Bayerl Ch , Kerowgan M 
Published: March 2003

Background: Cutaneous heparin‐induced allergic reactions to subcutaneous heparin may begin 2–5 days after administration. The relation of the delayed‐type hypersensitivity and a systemic immunologic response is controversial. The present investigation aimed to analyze the occurrence of thromboembolic complication, pathologic heparin‐induced platelet activation (HIPA), and the presence of circulating heparin‐induced IgG in patients with heparin‐induced skin reactions. Methods: Intracutaneous tests, HIPA assay, and heparin‐heparin IgG antibodies were performed in nine patients with heparin‐induced skin lesions. Results: Six of eight patients showed positive intracutaneous tests to heparin and to four low‐molecular‐weight heparins. Three of six heparin‐positive patients presented hypersensitivity to a heparinoid, too. Two of three patients had a positive HIPA test and elevated heparin‐induced IgG antibodies. Both patients developed complications presenting as heparin‐induced skin necrosis or arterial thrombosis. Two of nine patients were treated with danaparoid, 4/9 patients received r‐hirudin, and 1/9 received oral coumarin. In 2/9 patients, anticoagulant therapy was stopped, but these patients will receive r‐hirudin if indicated. Conclusions: On the basis of the coincidence of local and systemic hyperreactivity to heparin and danaparoid, patients with heparin‐induced skin lesions should receive r‐hirudin, a nonheparin compound, for anticoagulant treatment.
Wheat allergy: diagnostic accuracy of skin prick and patch tests and specific IgE
Authors: Majamaa H , Moisio P , Majamaa H , Turjanmaa K , Holm K 
Published: March 2003

Background: Food allergy makes an important contribution to the pathogenesis of atopic eczema in infants. However, clinical data on cereal allergy are scanty. The objective was to study the relevance of patch testing, skin prick tests, and the concentration of wheat‐specific IgE antibodies (CAP RAST) in correlation with oral wheat challenge in infants with suspected wheat allergy. In particular, we aimed to determine whether the patch test could increase the diagnostic accuracy in detecting wheat allergy. Methods: The study material comprised 39 infants under the age of 2 years. Of these patients, 36 were suffering from atopic eczema and three had only gastrointestinal symptoms. The patients were subjected to a double‐blind, placebo‐controlled or open wheat challenge. Wheat‐specific IgE was measured by CAP RAST, and skin prick and patch tests were performed. Results: Of the total 39 wheat challenges, 22 (56%) were positive. Of the positive reactions, five involved immediate‐type skin reactions over a period of 2 h from the commencement of the challenge. In 17 patients, delayed‐onset reactions of eczematous or gastrointestinal type appeared. Of the infants with challenge‐proven wheat allergy, 20% showed elevated IgE concentrations to wheat, 23% had a positive skin prick test, and 86% had a positive patch test for wheat. The specificities of CAP RAST, skin prick tests, and patch tests were 0.93, 1.00, and 0.35, respectively. Conclusions: Our study demonstrated that patch testing with cereals will significantly increase the probability of early detection of cereal allergy in infants with atopic eczema and is helpful in the planning of successful elimination diets before challenge. The specificity of the patch test was lower than that of other tests. Therefore, confirmation of the diagnosis with the elimination‐challenge test is essential in patients with positive patch test results.
Risk factors associated with asthma and rhinoconjunctivitis among Swedish farmers
Authors: Kronqvist M. , Johansson E. , Johansson S.G.O. , Van Hage‐Hamsten M. , Kronqvist M. , Pershagen G. 
Published: March 2003

Background: Earlier studies have shown a high prevalence of respiratory symptoms in farming communities and that storage mites constitute important allergens. We examined risk factors associated with asthma and rhinoconjunctivitis among Swedish farmers. Methods: A population of 1015 small‐scale dairy farmers was part of an epidemiologic survey. After selection based on symptom reports in a questionnaire, 461 of the farmers attended a medical examination, which comprised SPT, RAST analyses, and lung‐function measurements. Risk factors for sensitization to different allergens, and development of asthma and rhinoconjunctivitis were assessed by multiple logistic regression. Results: The prevalence of atopy was 26.7% among the farmers. For both asthma and rhinoconjunctivitis, sensitization to mites (OR=5.8 vs OR=3.8) and pollens (OR=10.3 vs OR=5.8) was a significant risk factor. There was a significant relationship between sensitization to mites and working time (OR=5.2). Environmental tobacco smoke and exposure to different animal species at the farm did not appear to affect the risk of allergen sensitization or respiratory symptoms. Farmers smoked less than the general population, but they more frequently had reduced FEV1. Conclusions: Allergen sensitization, especially to mites and pollens, was significantly associated with asthma and rhinoconjunctivitis in a farming community. The results point to allergen avoidance as a major goal for the prevention of occupational respiratory diseases among the farming population.
Exposure to an abundance of cat (Fel d 1) and dog (Can f 1) allergens in Swedish farming households
Authors: Parvaneh S , Kronqvist M , Johansson E , Van Hage‐Hamsten M 
Published: March 2003

Background: Earlier studies have shown that farmers are to a low degree sensitized to animal allergens. We have measured the amount of cat (Fel d 1) and dog (Can f 1) in farm households and examined the relationship between exposure and sensitization to cat and dog allergens. Methods: Dust samples from the homes of 403 farmers who had participated in an epidemiologic follow‐up study on respiratory symptoms were analyzed for allergen content by two‐site ELISA methods. Results: Fel d 1 was detected in 99.5% of the farmers' households ranging from 0.055 to 1455 μg/g dust in mattresses (GM 13.2) and to 3775 μg/g dust in living‐room carpets (GM 17.1). Can f 1 was detected in 90.6% of the households from 0.2 to 116 μg/g dust in mattresses (GM 2.0) and to 504 μg/g dust in carpets (GM 4.3). Homes with pets present had the highest levels of the allergens (P<0.001). A total of 8.4% and 7.4% of the farmers were sensitized to cat and dog, respectively. A significant correlation was noted between exposure to the allergens and specific IgE to cat and dog, respectively (P<0.001). Sensitization to cat (OR=4.9) and dog (OR=17.8) was significantly associated with asthma. Conclusions: In spite of the abundance of Fel d 1 and Can f 1, farmers are only to a low degree sensitized to cats and dogs.
Cytokine profiles of BAL T cells and T‐cell clones obtained from human asthmatic airways after local allergen challenge
Authors: Bodey K.J. , Semper A.E. , Redington A.E. , Madden J. , Teran L.M. , Holgate S.T. , Frew A.J. 
Published: March 2003

Background: This study assessed the heterogeneity of cytokine expression in asthma before and after local allergen challenge.Methods: BAL T cells were obtained 10 min or 24 h after local endobronchial allergen challenge in atopic asthmatic subjects. T cells were cloned by direct limiting dilution. mRNA expression was assessed by RT‐PCR, and cytokine protein production by ELISA.Results: Unstimulated baseline BAL T cells expressed mRNA for IFN‐γ, IL‐13, and TNF‐α. A minority of samples expressed IL‐4 and IL‐5, but no IL‐3 mRNA was detected. PHA stimulation increased expression of IL‐3, IL‐4, and IL‐5 mRNA in 4/6 samples. IL‐13 and GM‐CSF mRNA were found in BAL cells after allergen challenge, but expression of IFN‐γ was reduced. Both IL‐4 and IL‐3 were strongly upregulated after PHA stimulation, while the expression of TNF‐α and IFN‐γ was reduced, compared to equivalent baseline samples. Seventeen panels of BAL T‐cell clones were derived (average cloning efficiency 1/40 T cells). Seven panels survived to 8 weeks for analysis. Clones derived 4 h after saline challenge showed strong mRNA signals for IL‐13, IL‐4, and IFN‐γ, whereas clones derived 24 h after allergen challenge expressed IL‐13, GM‐CSF, IL‐3, IL‐4, and often IL‐5 (i.e., closer to the Th2 profile). There was considerable heterogeneity in the patterns of cytokine mRNA and protein production by different clones.Conclusions: T cells from asthmatic airways produce IL‐13, IFN‐γ, and TNF‐α, but after allergen challenge, type 2 cytokines are upregulated. mRNA and protein analysis provide complementary information on airways T‐cell cytokine profiles.Abbreviations: BAL: bronchoalveolar lavage; FEV1: forced expiratory volume in 1 s; IFN: interferon; IL: interleukin; PBMC: peripheral blood mononuclear cells; PBS: phosphate‐buffered saline; PC: cumulative provocative concentration producing 20% fall in FEV1; PE: phycoerythrin; Per‐CP: peridin chlorophyll‐protein conjugate; PHA: phytohaemagglutinin; TNF: tumour necrosis factor.
Allergic disease in teenagers in relation to urban or rural residence at various stages of childhood
Authors: Nilsson L , Castor O , Kjellman N‐im , Löfman O , Magnusson A 
Published: March 2003

Background: Higher prevalences of allergic diseases and IgE antibodies to inhalant allergens have been reported for persons living in urban areas than for persons living in rural areas. Methods: Associations between cumulative incidences of allergic diseases in 1878 children aged 13–14 years and their place of residence (urban, semiurban, or rural) from birth were assessed by questionnaire (ISAAC), in order to find out whether there is a period of increased sensitivity to external influences during the first few years of life. Family history and exposure to pets, tobacco smoke, and damp were considered in multiple regression. Results: There was a significantly higher prevalence of allergic diseases with urban residence than with rural residence during the first 2 years of life (e.g., for bronchial asthma, relative risk (RR) for the first year 2.1, 95% CI 1.2–3.7). An increased risk was still found after multiple regression (RR=1.7). Semiurban residence was associated with an intermediate cumulative incidence of allergic diseases. Maternal smoking during pregnancy was associated with asthma (RR=1.4, 95% CI 1.0–2.0). Conclusions: The findings support a period of increased susceptibility during the first years of life. Whether rural lifestyle protects against allergy or whether urban pollutants contribute to allergy has to be elucidated.
Clinicoimmunologic studies on Phoenix sylvestris Roxb. pollen: an aeroallergen from Calcutta, India
Authors: Chakraborty P. , Chowdhury I. , Gupta‐bhattacharya S. , Chanda S. , Gupta S. , Sengupta D.N. 
Published: March 2003

Background: This study highlights the allergenicity and allergenic components of the pollen of Phoenix sylvestris Roxb. (PS), or date sugar palm, which is predominantly airborne in the air of Greater Calcutta. Methods: A 2‐year aerobiologic survey was performed by Burkard sampler. PS pollen extract was used in skin tests of allergic patients, fractionated by (NH4)2SO4 and the SephacrylS‐200 column. The allergenicity of each fraction was checked by skin test and IgE ELISA inhibition. The principal allergenic fraction, Fr.IIa, was separated in 11% SDS–PAGE, and its allergenicity was confirmed by IgE ELISA inhibition and immunoblotting. Results: PS pollen grains were found to be prevalent in the air of the suburban zone of Calcutta from January to March with a peak in February. The pollen extract showed high (44.07%) positive skin reaction on 540 respiratory allergic patients. Among the (NH4)2SO4 cut fractions, Fr.II was the most active one, and it was resolved into four subfractions in the Sephacryl S‐200 column. Fr.IIa was the principal allergenic fraction, showing the presence of two components of 33 and 66 kDa in SDS–PAGE. In IgE immunoblotting, both of the components were found to be allergenic. Conclusions: The PS pollen grain is an important aeroallergen from Calcutta, India. The 33‐ and 66‐kDa components are the major allergens present in the relevant pollen extract.
Allergen‐specific immunotherapy in birch‐ and grass‐pollen‐allergic rhinitis. II. Side‐effects
Authors: Winther L. , Malling H.‐J. , Mosbech H. 
Published: March 2003

Background: Allergen‐specific immunotherapy (IT) involves the risk of side‐effects. Different side‐effect profiles have been reported for different allergens, and it would be of great benefit to be able more precisely to predict patient‐ and allergen‐related risk factors. Methods: Fifty‐two patients with rhinoconjunctivitis and allergy to birch as well as grass pollen participated in a 3‐year IT study, with a baseline year followed by 2 years of treatment. During the first treatment year, the patients received double‐blinded IT with either birch (Betula verrucosa) or grass (Phleum pratense) pollen extracts adsorbed to aluminum hydroxide. The following year, the other allergen extract was added. Assessment of systemic reactions (SRs) was performed, and related to patient pretreatment parameters such as seasonal symptoms and medication requirement, skin prick test (SPT), conjunctival provocation test (CPT), nasal provocation test (NPT), total and specific IgE, basophil histamine release (HR), eosinophil count (EOS), eosinophil cationic protein (ECP), and eosinophil protein X (EPX). Results: In total, 44 and 47 patients started IT with birch‐ and grass‐pollen extracts, respectively. All SRs occurred during the dose‐increase phase. No life‐threatening SRs were observed. There were a higher number of patients with SRs during IT with grass pollen than IT with birch pollen, 21 vs five patients (P<0.001), with SRs to 3.3% of grass‐pollen injections compared to 0.7% of birch‐pollen injections (P<0.0001). The SRs of birch‐pollen IT were mild, consisting of rhinoconjunctivitis and oral‐pharyngeal itching, whereas asthma and urticaria episodes were observed in the grass‐pollen IT. No difference was found in sensitivity to birch and grass, when measured by SPT, CPT, NPT, specific IgE, or HR, and no difference was found in age, duration of allergic symptoms, prevalence of asthma, mean seasonal birch/grass symptom score, eye‐drop use, or antihistamine or prednisolone intake between the group with and without subsequent SRs to IT. No difference was found in EOS, serum ECP, or EPX, between the group with and without subsequent SRs to IT. Conclusions: IT with grass‐pollen extract seems to be associated with a higher number and more severe SRs than birch‐pollen IT. Neither demographic data nor diagnostic tests of allergy such as specific IgE, HR, SPT, CPT, and NPT could identify the patients with subsequent SRs.
Correlation between atopic diseases and tuberculin responses
Authors: Yılmaz M. , Bingöl G. , Altıntaş D. , Kendirli S. G. 
Published: March 2003

Background:In recent decades, the prevalence of atopic diseases has risen steadily in developed countries. The reasons for this increase are not clear. It has been hypothesized that a reduction in infections and immunization programs may contribute to the increase in the prevalence of atopic diseases. We investigated the relationship between tuberculin response and atopic disease.Methods:A total of 538 (73.0%) atopic and 198 (27.0%) nonatopic children vaccinated with BCG were included in the study. All the children included in the study had neither been given BCG nor tuberculin skin‐tested in the previous 6 months, nor did they have a condition known to cause anergy. All the children were given five tuberculin units PPD, and PPD indurations were recorded after 48 h.Results:The PPD induration size was 6.8±5.6 mm (mean±SD) in atopic children and 7.4±5.9 mm in nonatopic children. The difference between the two groups was not significant (P>0.05). The PPD induration sizes of children with asthma, rhinitis, and atopic dermatitis were found to be similar. The children with atopic dermatitis had lower PPD induration size, but this was not statistically significant (P>0.05). The rates of negative (<5 mm skin induration) and intermediate (5–9 mm) responses were 32.6% and 30.5% in atopic children and 30.2% and 32.4% in nonatopic children, respectively. Positive tuberculin responses (PPD≥10 mm) were recorded in 36.9% of atopic children and 37.4% of nonatopic children. Total serum IgE levels of atopic and nonatopic children were 623.35 and 46.78 IU/ml, respectively. There was no correlation between serum total IgE level and PPD induration size (r=−0.0012,P=0.737).Conclusions:We did not find any relationship between tuberculin response and atopy status later in life in BCG‐immunized subjects. We need further studies to clarify the effect of BCG on the development of atopy.
Selective upregulation of a functional β7 integrin on differentiating eosinophils
Authors: Lundahl J. , Sehmi R. , Hayes L. , Howie K. , Denburg J. A. 
Published: March 2003

Background: The sequence of adhesion‐molecule expression during eosinophil differentiation remains unclear. Methods: We analyzed the surface expression of α4, β1, and β7 integrins and compared it to established myeloid developmental markers, using the eosinophilic cell line HL‐60 clone 15, as well as cord and peripheral blood differentiation assays. Results: Cells induced to eosinophil differentiation by treatment with butyric acid, IL‐5, and GM‐CSF showed a significant upregulation of β7 integrin expression coincident with a marked upregulation of CD35 and attenuation of CD33 and β1 integrin expression. In addition, adhesion of induced HL‐60 clone 15 cells to fibronectin was attenuated by a β7 integrin antibody. Conclusions: Our data show that protein synthesis‐dependent upregulation of the functional β7 integrin occurs under conditions when α4 and β1 integrins are fully expressed, indicating a sequential appearance of specific adhesion molecules on differentiating eosinophil progenitors.
The effect of platelet‐activating factor (PAF) on nasal airway resistance in healthy subjects is not mediated by nitric oxide
Authors: Maniscalco M. , Sofia M. , Faraone S. , Carratù L. 
Published: March 2003

Background: The nose is an important source of nitric oxide (NO) in man, but the relevance of NO production to the response to inflammatory mediators is not clear. Methods: In this study, we evaluated the effect of NO inhibition on nasal airway resistance (NAR) at baseline, after an acute challenge with platelet‐activating factor (PAF), a potent proinflammatory factor, and after an acute challenge with bradykinin (BK), both of which are mediators of allergic rhinitis in man. Eight healthy subjects were enrolled in the study. Nasal NO production was measured by the chemiluminescence method, and NAR was measured by active anterior rhinomanometry. Results: Basal nasal NO concentration was 500.6±115.6 ppb; it significantly decreased after topical administration of the NO‐synthase inhibitor L‐NAME, and the NO‐synthase substrate
l‐arginine caused a recovery in NO production. The administration of L‐NAME did not cause any change in basal NAR. In a double‐blind fashion, we performed nasal challenge with PAF and BK after topical pretreatment with either placebo or L‐NAME. After placebo pretreatment, both PAF and BK caused a significant increase in NAR (respectively, from 0.29±0.11 Pa s cm−3 to 0.75±0.21 Pa s cm−3, and from 0.36±0.18 Pa s cm−3 to 0.71±0.25 Pa s cm−3; P<0.001, n=8). Pretreatment with L‐NAME did not prevent the PAF‐induced increase in NAR (from 0.31±0.10 Pa s cm−3 to 0.71±0.27 Pa s cm−3), whereas it prevented the BK‐induced increase in NAR (from 0.33±0.15 Pa s cm−3 to 0.43±0.16 Pa s cm−3). Conclusions: Topical administration of the NO‐synthase inhibitor L‐NAME at doses sufficient to decrease NO nasal production does not prevent the PAF‐induced increase in NAR, indicating that NO generation in vivo is not involved in the nasal response to PAF.
Allergy to Diplotaxis erucoides pollen: occupational sensitization and cross‐reactivity with other common pollens
Authors: García‐Ortega P. , Bartolomé B. , Enrique E. , Gaig P. , Richart C. 
Published: March 2003

Background: Diplotaxis erucoides is a common weed of the Brassicaceae family widespread in southern and central Europe. Methods: A total of 410 consecutive patients referred for allergy study of rhinoconjunctivitis and/or asthma were skin tested with D. erucoides pollen, 14 proving positive. A purified D. erucoides pollen extract was prepared to perform quantitative skin tests, provocation tests, immunoblotting, and EIA inhibition in the 14 sensitized patients. Results: Three patients, directly involved in viniculture, had rhinoconjunctivitis related to D. erucoides pollen. No D. erucoides‐related symptoms were observed in most patients, who were also sensitized to Artemisia pollen. RAST was positive in 12/14 patients and nasal provocation tests in 9/12. The molecular masses of the most prevalent IgE‐binding proteins ranged from 26 to 27.5 and from 31 to 34 kDa. D. erucoides pollen inhibited the IgE‐binding of other sensitizing pollens in the three viniculture workers, whereas both Artemisia and D. erucoides pollen produced similar heterologous inhibition in the pooled serum of the remaining, nonclinically affected, D. erucoides‐sensitized patients. Conclusions: D. erucoides pollen may be an important prevalent aeroallergen, particularly in rural areas. It may act as an occupational allergen in vineyard workers, in whom it seems to be the primary sensitizing agent, playing a secondary cross‐reactive role in other sensitized patients.