Biomedical subjects

Dietrich Reinhardt

Publications and source records attributed to Dietrich Reinhardt.

17 recordsLinked to original sources

PubMed2006

Interaction of polyamine gene vectors with RNA leads to the dissociation of plasmid DNA-carrier complexes.

BACKGROUND: Plasmid DNA (pDNA) dissociation from polyamine gene vectors after cellular uptake has not been well characterized. A more detailed understanding of this process could lead to more efficient gene transfer agents. Since RNA is present in the cytoplasm at high concentrations and due to its structural similarity to DNA, we were interested in its conceivable interaction with polyamine gene vectors. METHODS: In a first set of experiments gene vectors were incubated in cell lysate and pDNA release was investigated by Southern blot analysis with or without RNase A pretreatment and by confocal laser scanning microscopy. Further, interaction of polyamine gene vectors with RNA was investigated by fluorescence quenching assay. These methods were complemented by a functionality assay using isolated nuclei. RESULTS: The incubation of gene vectors with cell lysate resulted in the dissociation of pDNA from the complexes. This effect was abolished when the cell lysate was pretreated with RNase A. The addition of RNA in the absence of cell lysate led also to a dissociation of pDNA. This process commenced instantaneously after the addition of RNA as analyzed by fluorescence quenching. When gene vectors were incubated in cell lysate containing isolated nuclei, the dissociation of pDNA from the polyamine gene vectors occurred preferentially extranuclearally as confirmed by confocal laser scanning microscopy. These results were further corroborated in a functional assay. CONCLUSIONS: These data suggest that RNA induces pDNA dissociation from the polyamine gene vectors. Furthermore, this process apparently occurs in the cytoplasm before the gene vectors enter the nucleus.

Cell Nucleus↗

PubMed2006

Surfactant protein D regulates chemotaxis and degranulation of human eosinophils.

The collectin surfactant protein D (SP-D) is an important component of the pulmonary innate host defence. Up to now, little is known about the regulation of eosinophil function by SP-D. Various murine models of pulmonary hypersensitivity suggest that SP-D may be a potent anti-allergic protein. We investigated the modulation of eosinophil chemotaxis and degranulation by human SP-D. SP-D markedly inhibited the chemotaxis of eosinophils triggered by eotaxin, a major tissue-derived CC-chemokine, as shown in a modified Boyden chamber assay. In addition, degranulation of ECP in response to Ca2+ ionophore, immobilized IgG and serum from allergic patients was inhibited by SP-D. In a fixed-cell enzyme linked immunosorbent assay and in flow cytometry, SP-D bound to eosinophils. This binding was saturable and was inhibited by the addition of maltose and ethylenediaminetetraacetic acid, suggesting the involvement of the carbohydrate recognition domain of SP-D. In addition, flow cytometry showed significant interaction of SP-D with CD32 (FcgammaII receptor) on eosinophils, which might explain the inhibitory effect of SP-D on the IgG and serum-triggered eosinophil cationic protein degranulation of eosinophils. Our data further support the concept of an anti-inflammatory function of SP-D in the lung of patients with allergic diseases.

Adult↗

PubMed2005

Uronic acids functionalized polyethyleneimine (PEI)-polyethyleneglycol (PEG)-graft-copolymers as novel synthetic gene carriers.

In this study, we investigated galacturonic (GalAc)- and mannuronic (ManAc) acids as novel targeting ligands for receptor-mediated gene delivery. GalAc and ManAc were coupled to either polyethyleneimine (PEI) or PEI-polyethyleneglycol (PEG). Furthermore, lactobionic acid (LacAc), which comprises a GalAc-related carbohydrate ring, was coupled to each of the polymers through its open-chain gluconic acid moiety. The molar mass distributions of the polymers were characterized by analytical ultracentrifugation and size exclusion chromatography. PEI-conjugate-pDNA complexes were transfected into HepG2-, HeLa-, and 16HBE14o(-)-cells. Gene expression mediated by GalAc- and LacAc-functionalized PEI-conjugates was lower than for PEI. In contrast, gene expression mediated by ManAc-functionalized PEI-conjugates was up to three orders of magnitude higher than for the other tested PEI-conjugates, in particular for negatively charged gene vectors at low N/P ratios, independent of the cell line. Pre-incubation of cells with an excess of ManAc before transfection significantly inhibited transfection rates only for ManAc-functionalized PEI-conjugates. Coupling of methyl-alpha-d-mannuronic acid to PEI resulted in significantly lower transfection rates than for ManAc-PEI based complexes. Together with fluorescence microscopy images of fluorescein-labelled ManAc-functionalized dextrans and FACS analyses of cells, these results demonstrate that receptor-mediated endocytosis of ManAc-PEI-conjugate-pDNA complexes via ManAc-specific receptors was involved in gene transfer. In conclusion, ManAc-modification of PEI-polymers represents a novel strategy for receptor-mediated gene delivery which could be promising for in vivo application.

Animals↗

PubMed2005

Parenteral nutrition is not superior to replacement fluid therapy for the supportive treatment of chemotherapy induced oral mucositis in children.

Many paediatric oncology centres apply parenteral nutrition (PN) in children with severe oral mucositis after chemotherapy. However, no convincing data exist to support this treatment strategy. The aim of our study was to elucidate a possible advantage of PN versus intravenous replacement fluid therapy (FT). In a prospective randomized study, 30 children with mucositis WHO grade IV were assigned to receive either PN or intravenous replacement FT. Weight, total body water, fat-free mass (measured by impedance analysis) and peripheral white blood cells were assessed daily. For aspects of quality of life and economics, the length of hospital stay, the incidence of infections, the days on intravenous antibiotics and delay of scheduled chemotherapy were examined. Children with PN gained body weight significantly compared to baseline and to FT due to an augmentation of fat mass while total body water and fat-free mass significantly decreased. In children with FT, body weight remained stable while total body water and fat-free mass significantly increased, thereby loosing fat mass. We observed no differences in recovery of peripheral white blood cells (WBC), incidence of infections, hospitalization time, days on intravenous antibiotics, days on opioid analgesics and delay of the next scheduled chemotherapy cycle. Although children with PN gained weight in form of fat mass, this did not translate into a clinical benefit for the patients such as earlier recovery of WBC counts, shorter hospitalization time, a decreased use of analgesics or less delay of the next scheduled chemotherapy cycle. Our findings therefore do not support the hypothesis that PN is superior to FT when used for less than 10 days for oral mucositis.

Adolescent↗

PubMed2005

Pulmonary T(H)2 response in Pseudomonas aeruginosa-infected patients with cystic fibrosis.

BACKGROUND: Pseudomonas aeruginosa infection determines the course of cystic fibrosis (CF) lung disease. Studies in human peripheral blood indicate that P aeruginosa infection is associated with a predominant T(H)2 immune response, whereas T(H)1 responses are accompanied by a better pulmonary outcome. OBJECTIVE: Analyses of peripheral blood may not correspond directly with the local pulmonary immune response. Therefore, we asked whether the T(H)1/T(H)2 response is altered in bronchoalveolar lavage fluid from P aeruginosa-infected patients with CF. METHODS: Bronchoalveolar lavage fluid was obtained from 12 patients with CF chronically infected with P aeruginosa, 11 noninfected patients with CF, and 8 healthy controls. Pulmonary CXCR3(+) (T(H)1) and CCR4(+) (T(H)2) expressing CD4(+) and CD8(+) lymphocytes were quantified by flow cytometry. Levels of T(H)1-associated (IL-2, IFN-gamma, IFN-gamma inducible T cell-alpha chemoattractant, Monokine induced by IFN-gamma, IFN-gamma inducible protein of 10 kd) and T(H)2-associated (IL-4, IL-5, IL-10, thymus and activation-regulated chemokine [TARC], macrophage-derived chemokine) cytokines and chemokines and a panel of proinflammatory molecules were quantified at the protein level. Chemokines mRNA levels were assessed by real time RT-PCR. RESULTS: P aeruginosa-infected patients with CF had significantly higher levels of pulmonary CCR4(+)CD4(+) (T(H)2) cells, IL-4, IL-13, and TARC and lower levels of IFN-gamma compared with noninfected patients with CF and healthy controls. Bronchoalveolar lavage fluid levels of IL-4, IL-13, and TARC correlated inversely with FEV(1) in P aeruginosa-infected patients with CF. CONCLUSION: These results reveal the prevalence of a pulmonary T(H)2 immune response in P aeruginosa-infected patients with CF. The modulation of the pulmonary T(H)2 response in P aeruginosa infection may be an option for the treatment of P aeruginosa lung disease in patients with CF.

Adolescent↗

PubMed2005

A role for MCP-1/CCR2 in interstitial lung disease in children.

BACKGROUND: Interstitial lung diseases (ILD) are chronic inflammatory disorders leading to pulmonary fibrosis. Monocyte chemotactic protein 1 (MCP-1) promotes collagen synthesis and deletion of the MCP-1 receptor CCR2 protects from pulmonary fibrosis in ILD mouse models. We hypothesized that pulmonary MCP-1 and CCR2+ T cells accumulate in pediatric ILD and are related to disease severity. METHODS: Bronchoalveolar lavage fluid was obtained from 25 children with ILD and 10 healthy children. Levels of pulmonary MCP-1 and Th1/Th2-associated cytokines were quantified at the protein and the mRNA levels. Pulmonary CCR2+, CCR4+, CCR3+, CCR5+ and CXCR3+ T cells were quantified by flow-cytometry. RESULTS: CCR2+ T cells and MCP-1 levels were significantly elevated in children with ILD and correlated with forced vital capacity, total lung capacity and ILD disease severity scores. Children with lung fibrosis had significantly higher MCP-1 levels and CCR2+ T cells in bronchoalveolar lavage fluid compared to non-fibrotic children. CONCLUSION: The results indicate that pulmonary CCR2+ T cells and MCP-1 contribute to the pathogenesis of pediatric ILD and might provide a novel target for therapeutic strategies.

Adolescent↗

PubMed2005

Pulmonary chemokines and their receptors differentiate children with asthma and chronic cough.

BACKGROUND: Cough is a frequent symptom in children, but the differentiation of asthmatic cough from cough of other origins can be difficult. Chemokines recruit T lymphocytes to inflamed tissues, and the corresponding chemokine receptors are differentially expressed on T H 1 and T H 2 cells. OBJECTIVE: We sought to determine whether levels of T H 1/T H 2-related chemokines and their receptors differ in bronchoalveolar lavage fluid (BALF) from 12 children with allergic asthma, 15 nonatopic children with chronic cough, and 10 children without airway disease. METHODS: The T H 1-related (IFN-gamma-inducible protein of 10 kd [IP-10], IFN-gamma-inducible T cell alpha chemoattractant [ITAC], monokine induced by IFN-gamma [Mig], and IFN-gamma) and T H 2-related (thymus- and activation-regulated chemokine [TARC], macrophage-derived chemokine [MDC], IL-5, and IL-4) chemokines and cytokines were quantified in BALF by ELISA and a particle-based multiplex array. Percentages of pulmonary lymphocytes expressing CXCR3 + and CCR5 + (T H 1) and CCR4 + and CCR3 + (T H 2) chemokine receptors were determined in BALF by flow cytometry. RESULTS: Pulmonary CCR4 + CD4 + cells and levels of TARC and MDC were significantly increased in asthmatic children versus children with chronic cough or without airway disease. In asthmatic children CCR4 + CD4 + cells correlated positively with levels of TARC, MDC, and serum IgE levels and negatively with FEV 1 . In contrast, CXCR3 + CD8 + cells and levels of ITAC were significantly increased in children with non-atopic chronic cough compared with the other groups. In children with chronic cough, CXCR3 + CD8 + cells correlated with levels of ITAC and IFN-gamma. CONCLUSION: Pulmonary CCR4 + CD4 + and CXCR3 + CD8 + cells and their ligands TARC, MDC, and ITAC clearly differentiate asthmatic children from nonatopic children with chronic cough. The analysis of these markers could facilitate the diagnostic discrimination of asthma versus other reasons for chronic cough in children.

Adolescent↗

PubMed2005

Increase of antigen-presenting cells in the gastric mucosa of Helicobacter pylori-infected children.

BACKGROUND: Infection with Helicobacter pylori leads to an increase of T cells in the gastric mucosa of children. In contrast to peripheral blood, where monocytes are the most abundant antigen-presenting cells, CD14+ macrophages are very rare in infected gastric mucosa. We postulated that other types of antigen-presenting cells must be present in infected gastric mucosa. MATERIAL AND METHODS: Antral biopsies were obtained from 56 children. The cellular expression of major histocompatibility complex (MHC) class II molecules, CD1a/b, and CD23, which are involved in antigen presentation were analyzed by immunohistochemistry. In addition, T cells (CD4, CD8, CD25, and gamma/delta-TCR), B cells (anti-IgM), macrophages (CD14) and granulocytes (CD15) were quantified. RESULTS: Twenty-eight children were H. pylori-infected. Thirteen children were healthy, 15 had other gastric pathologies. T cells (p<.0001), B cells (p<.0001), CD23+ (p<.0001), and CD1a/b+ (p<.005) cells were significantly increased in the lamina propria of H. pylori-infected children, whereas macrophages were rare without significant differences among the groups. Within the epithelium, CD8+ T lymphocytes predominated clearly over CD4+ cells. H. pylori-negative children had only few MHC class II-positive cells within the gastric epithelium, whereas MHC class II antigens were strongly expressed on epithelial cells (p<.0001) of all H. pylori-infected children. CONCLUSION: Helicobacter pylori infection leads to an enhanced expression of antigen-presenting molecules together with a parallel rise of T cells in the lamina propria. This may represent an effort of the immune system to optimize local immune responses against H. pylori. We speculate that the epithelium participates in the initiation of a local immune response against H. pylori.

Adolescent↗

PubMed2004

Gene delivery to respiratory epithelial cells by magnetofection.

BACKGROUND: For the topical application of DNA vector complexes to the airways, specific extracellular barriers play a major role. In particular, short contact time of complexes with the cell surface caused by the mucociliary clearance hinders cellular uptake of complexes. The aim of this study was to evaluate the ability of magnetofection, a technique based on the principle of magnetic drug targeting, to overcome these barriers in comparison with conventional nonviral gene transfer methods such as lipofection and polyfection. METHODS: Experiments were carried out on permanent (16HBE14o-) and primary airway epithelial cells (porcine and human), and native porcine airway epithelium ex vivo. Transfection efficiency and dose-response relationship of magnetofection were examined by luciferase reporter gene expression. Sedimentation patterns and uptake of gene transfer complexes were characterized by fluorescence and electron microscopy, respectively. RESULTS: We show that (i) application of a magnetic field allows the magnetofectins to sediment and to enrich at the cell surface within a few minutes, (ii) magnetofection bears an improved dose-response relationship, (iii) magnetofection enhances transfection efficiency in both, permanent and primary airway epithelial cells, and (iv) magnetofection leads to significant transgene expression at very short incubation times in an ex vivo airway epithelium organ model. CONCLUSIONS: Magnetofection provides a potential novel method, which may overcome fundamental limitations of nonviral gene transfer to the airways. Due to the accelerated enrichment at the cell surface it may be of major interest for in vivo applications, where long-term incubation times at the target tissue are hardly achievable.

Animals↗

PubMed2004

Effect of breast-feeding on the development of atopic dermatitis during the first 3 years of life--results from the GINI-birth cohort study.

OBJECTIVE: To investigate if exclusive breast-feeding for 4 months is associated with atopic dermatitis during the first 3 years of life. STUDY DESIGN: Data on 3903 children were taken from yearly parental-administered questionnaires from a birth cohort study in Germany (recruited 1995-1998) comprised of a noninterventional (NI) and an interventional (I) subgroup. Outcomes were physician-diagnosed atopic dermatitis (AD) and itchy rash. Multiple logistic regression was performed for the entire cohort and stratified by family history of allergy and by study group adjusting for a fixed set of risk factors for allergies. RESULTS: Exclusive breast-feeding (52 % of children) was not associated with higher risk for AD either in the entire cohort (OR(adj,) 0.95; 95% CI, 0.79-1.14) or if stratified by family history of AD. In the I subgroup, but not in the NI subgroup, exclusive breast-feeding showed a significant protective effect on AD if compared with conventional cow's milk formula (OR(adj), 0.64; 95% CI, 0.45-0.90). CONCLUSION: These findings do not support the hypothesis that exclusive breast-feeding is a risk factor for development of atopic dermatitis but is protective if compared with conventional cow's milk. Observational studies might not be able to effectively control for selection bias and reverse causation.

Animals↗

PubMed2004

Effect of enzyme-replacement therapy on gastrointestinal symptoms in Fabry disease.

Fabry disease is an X-linked recessive lysosomal storage disorder caused by deficiency of lysosomal alpha-galactosidase A. The disease affects not only kidney, myocardium, central nervous system and the skin but also, in many patients, the gastrointestinal tract. The recent advent of enzyme-replacement therapy has been reported to show beneficial effects on cardiomyopathy, renal function and autonomous nervous function. We report on a 34-year-old patient with Fabry disease in whom gastrointestinal symptoms were major complaints. Enzyme replacements led to remarkable improvement of diarrhoea and constipation. Abdominal pain, the feeling of fullness and meteorism improved, and metoclopramide, which previously had been used regularly, could be discontinued. There were also marked improvements of appetite, body weight, body mass index, physical activity and overall wellbeing. This observation should prompt further investigations into the pathophysiology of gastrointestinal manifestations in Fabry disease and the mechanisms of enzyme-replacement effects on gut function.

Adult↗

PubMed2003

A novel transfecting peptide comprising a tetrameric nuclear localization sequence.

The transport of exogenous DNA into the nucleus of eukaryotic cells is a prerequisite for successful gene delivery. To favor nuclear transport we synthesized a tetramer of the nuclear localization signal (NLS) of the SV40 large T-antigen as a novel nonviral gene delivery vector. This 4.4-kDa lysine-rich peptide (NLSV404) binds and compacts DNA by electrostatic interaction and forms stable polyplexes. Apart from its sequence-specific potency to mediate nuclear accumulation of conjugated albumin, NLSV404 also displays properties of nuclear transport for plasmid DNA as confirmed by fluorescence in situ hybridization. Further, NLSV404 polyplexes are shown to efficiently transfect various cell lines such as 16HBE14o-, HeLa S6, and Cos7 cells. NLSV404 polyplexes displayed at least 20-fold higher transfection rates than analogous polyplexes formed by the nuclear transport-deficient mutant sequence cNLS. Using growth-arrested cells, NLSV404 complexes were at least 100-fold more efficient than cNLS complexes. Combination of NLSV404 peptide but not of cNLS peptide with preformed polyethylenimine and dendrimer DNA complexes resulted in a strong increase in transfection efficiency. Incubation of cells prior to transfection with NLSV404 polyplexes with excess free peptide NLSV404 but not with cNLS resulted in a dose-dependent dramatic decrease in the transfection rate, suggesting a sequence-specific competitive inhibition. These results indicate that NLSV404 mediates nuclear accumulation of transfected plasmid DNA and that it can be a highly useful component of nonviral gene vectors.

Active Transport, Cell Nucleus↗

PubMed2003

Longitudinal follow-up of the changing gender ratio in asthma from childhood to adulthood: role of delayed manifestation in girls.

Boys suffer more often from asthma than girls, while in adults the gender ratio is reversed. It is not clear when exactly this change occurs and by what mechanism. From a cohort of all 5030 German 4th grade pupils (age 10 years) in Munich, 274 children with current asthma were identified (164 males, 110 females) through a questionnaire, and skin prick tests were performed. These subjects were re-evaluated at ages 14 and 20 years with a questionnaire. A random sample (n = 1000) of all 3538 German children without current asthma at age 10 was also re-evaluated at age 20 (controls). At age 20, only 24.5% (21 males, eight females) of the initial asthma group still had symptoms, and their gender ratio remained male dominated. In the controls, 4.8% (48/1000) had current asthma at age 20 and these were predominantly female: 6.4% (31/485) of control girls vs. 3.3% (17/515) of boys (p = 0.022). Half of the new asthma cases had had no symptoms or diagnoses until age 10, and atopy at age 10 was not associated with subsequent asthma in these. Asthma at age 10 has no better prognosis in boys than in girls, and the mechanism of the changing gender ratio appears to be late incidence of asthma among girls. Because the latter constitute a considerable part of adult asthma cases, it appears important to further explore this asthma phenotype and the risk factors associated with it.

Adolescent↗

PubMed2003

The effect of hydrolyzed cow's milk formula for allergy prevention in the first year of life: the German Infant Nutritional Intervention Study, a randomized double-blind trial.

BACKGROUND: The potential of extensively or partially hydrolyzed formulas to reduce the risks for allergies is controversial. OBJECTIVE: We sought to assess the preventive effect of differently hydrolyzed formulas compared with cow's milk formula (CMF) in high-risk infants. METHODS: Between 1995 and 1998, 2252 infants with a hereditary risk for atopy were enrolled in the German Infant Nutritional Intervention Study and randomly assigned at birth to one of 4 blinded formulas: CMF, partially hydrolyzed whey formula, extensively hydrolyzed whey formula, and extensively hydrolyzed casein formula (eHF-C). The primary end point at 1 year of age was the presence of allergic manifestation, which was defined as atopic dermatitis (AD), gastrointestinal manifestation of food allergy, allergic urticaria, or a combination of these factors. RESULTS: At 12 months per protocol, analysis was performed on 945 infants exposed to study formula: 304 (13.5%) infants had left the study, 138 (6.1%) infants were excluded because of noncompliance, and 865 infants were exclusively breast-fed the first 4 months of life. The incidence of allergic manifestation was significantly reduced by using eHF-C compared with CMF (9% vs 16%; adjusted OR, 0.51; 95% CI, 0.28-0.92), and the incidence of AD was significantly reduced by using eHF-C (OR, 0.42; 95% CI, 0.22-0.79) and partially hydrolyzed whey formula (OR, 0.56; 95% CI, 0.32-0.99). Family history of AD was a significant risk factor and modified the preventive effect of the hydrolysates. CONCLUSIONS: Prevention of allergic diseases in the first year of life is feasible by means of dietary intervention but influenced by family history of AD. The preventive effect of each hydrolyzed formula needs to be clinically evaluated.

Animals↗

PubMed2003

Frequency of Valpha24+CD161+ natural killer T cells and invariant TCRAV24-AJ18 transcripts in atopic and non-atopic individuals.

Th2 cells play a central role in type I allergies. However, the source of interleukin-4 which may lead to a Th1/Th2 imbalance is unknown. Valpha24+CD161+ Natural killer T (NKT) cells secrete high amounts of interleukin-4 and/or interferon-gamma and are assumed to participate in the initiation of Th1/Th2 immune responses. Their contribution to the development of Th2-dependent type I allergies is controversial. Our objective in this paper was to determine whether Valpha24+CD161+ NKT cells differ in atopic and non-atopic adults. Venous blood was obtained from thirteen atopic and sixteen healthy adult probands. Valpha24+CD161+ NKT cells were determined in CD4+, CD8(bright/dim) and CD4-CD8- lymphocytes by flow cytometry. At the molecular level, the amounts of T cell receptor (TCR) AV24-AJ18 transcripts were quantified with respect to TCRAV24 chain transcripts alone or to all TCR alpha chain transcripts. To detect potential inserted nucleotides in the N-region, a novel real-time PCR-based technology was applied. Both CD4+ and CD4-CD8- NKT cells were present at higher frequencies than CD8+ NKT cells in all probands. CD8(dim) NKT cell levels were lower in healthy individuals, although not statistically significantly different to the patients. Amounts of AV24-AJ18 transcripts in relation to total TCR alpha-chains and to TCRAV24 alone were equal in both proband groups. N-region diversity was detected in four clones from four different individuals, but altered the amino acid sequence in only one clone of an atopic donor. Analysis of Valpha24+CD161+ NKT cell frequencies at both the cellular and molecular levels failed to reveal significant differences in peripheral blood of atopic and non-atopic probands. If NKT cells contribute to development of type I allergies they must do so at earlier times or in other locations.

Adult↗

PubMed2002

Effect of exclusive breast-feeding and early solid food avoidance on the incidence of atopic dermatitis in high-risk infants at 1 year of age.

The aim of this study was to assess the preventive effect of exclusive breast-feeding and early solid food avoidance on atopic dermatitis (AD) in infancy. This study is part of a dietary clinical trial in a prospective cohort of healthy term newborns at risk of atopy. It was recommended to breast-feed for at least 4 months and to avoid solid food in the same time-period. Eight hundred and sixty-five infants exclusively breast-fed, and 256 infants partially or exclusively formula-fed, were followed-up until the end of the first year following birth. AD and sensitization to milk and egg were considered as study end-points. The 1-year incidence of AD was compared between the two study groups. Adjusted odds ratios (OR) with 95% confidence intervals (CI) were calculated by multiple logistic regression. The incidence of AD was calculated in relation to age at introduction of solid food and amount of food given. In the breast-fed group, the adjusted OR for AD was 0.47 (95% CI 0.30-0.74). The strongest risk factor was the occurrence of AD in the subject's core family. The risk of infants with AD to be sensitized to milk was four times higher, and to egg eight times higher, than in infants without AD. Age at first introduction of solid food and diversity of solid food showed no effect on AD incidence. We conclude that in infants at atopic risk, exclusive breast-feeding for at least 4 months is effective in preventing AD in the first year of life.

Breast Feeding↗

PubMed2002

Exposure to pets and atopic dermatitis during the first two years of life. A cohort study.

The aim of this study was to assess the association between keeping pets in early childhood and the occurrence of atopic dermatitis in an ongoing birth cohort followed up to the age of 2 years. We analyzed data of 4578 children in the intervention and observation part of an ongoing cohort study. The children were recruited at birth in the two study regions Wesel and Munich between January 1996 and June 1998. Information on atopic diseases and pet ownership was obtained by questionnaire at the child's first and second birthday. The logistic regression model showed a negative association between 'keeping any pet' and in particular 'keeping dogs' in the 1st year of life and the development of atopic dermatitis in the 1st and the 2nd years of life. The protective effects remained statistically significant after adjusting for several possible confounding variables (1st year(any) pet OR 0.71, 95% CI [0.55;0.92], 1st year(dog) OR 0.62, 95% CI [0.39;0.98], 2nd year(any) pet OR 0.74, 95% CI [0.57;0.97], 2nd year(dog) OR 0.63, 95% CI [0.40;0.98]). Ownership of small furred pets (hamster, rabbit and guinea pig) also showed a borderline protective effect for the 1st year. We assume an association between keeping pets and undefined environmental factor(s) that contribute protectively to the development of atopic dermatitis in early life, presumably by effects on the maturation of the immune system.

Animals↗