High breast milk IL-1ß level is associated with reduced risk of childhood eczema.

BACKGROUND: We recently demonstrated a dual effect of breastfeeding with increased risk of eczema and decreased risk of wheezing in early childhood by increasing breastfeeding length. We hypothesize that immune mediators in breast milk could explain such association either through a direct effect or as a surrogate marker of maternal immune constitution. OBJECTIVE: To investigate the possible association between cytokine and chemokine levels in breast milk and development of eczema and recurrent wheeze during early childhood. METHODS: Levels of 19 pro-inflammatory and immunoregulatory cytokines and chemokines were measured in 223 breast milk samples from mothers in the Copenhagen Prospective Study on Asthma in Childhood2000 (COPSAC) high-risk birth cohort. Eczema and recurrent wheeze at the age of 0-3 years were prospectively diagnosed by COPSAC physicians adherent to predefined validated algorithms. Association analyses were performed by Cox regression adjusting for potential confounding factors and by multivariable principal component analysis. RESULTS: Increased IL-1ß in breast milk (≥ 0.7 pg/mL) was associated with more than a halved risk of eczema before age three (aHR = 0.41; 95% CI = 0.24-0.68; P < 0.001), which remained significant after false discovery rate adjustment (P = 0.008). The principal component analysis confirmed that a mediator pattern dominated by high levels of IL-1ß, IL-17A, and CCL17 and low levels of CXCL1 and TSLP in breast milk protected against eczema (aHR = 0.82; 95% CI = 0.68-0.98; P = 0.03). No associations were observed for recurrent wheeze. CONCLUSIONS AND CLINICAL RELEVANCE: Elevated breast milk IL-1ß level was associated with decreased risk of early childhood eczema suggesting either a direct protective effect of IL-1ß or IL-1b acting as a proxy for a healthy maternal immune system protecting high-risk offspring from eczema.

Enabling sense-making for patients receiving outpatient palliative treatment: A participatory action research driven model for person-centered communication.

OBJECTIVES: In clinical palliative cancer care, the diversity of patient concerns over time makes information provision a critical issue, the demands of information-seeking patients presenting a challenge to both the communicative and organizational skills of the health provider. This study puts forward a practice model for communication between patients, their family members, and professional health providers during ongoing palliative chemotherapy; a model which supports the providers in enabling person-centered communication. METHOD: A constant comparative analysis adapted to participatory action research was applied. The model was developed step-wise in three interrelated cycles, with results from previous studies from palliative cancer care processed in relation to professional health providers' experience-based clinical knowledge. In doing this, focus group discussions were carried out with providers and patients to develop and revise the model. RESULTS: The Enabling Sense Making model for person-centered communication gave rise to three domains (which are also the major communicative actors in palliative care): the patient, the family, and the provider. These actors were placed in the context of a communicative arena. The three respective domains were built up in different layers discriminating between significant aspects of person-centered communication, from the manifest that is most usually explicated in dialogues, to the latent that tends to be implicitly mediated. SIGNIFICANCE OF RESULTS: The model intends to facilitate timely reorientation of care from curative treatment or rehabilitation to palliation, as well as the introduction of appropriate palliative interventions over time during palliative phases. In this way the model is to be regarded a frame for directing the awareness of the professionals, which focuses on how to communicate and how to consider the patient's way of reasoning. The model could be used as a complement to other strategic initiatives for the advancement of palliative care communication. It needs to be further evaluated in regard to practice evidence.

Measurement of the spatial phase shift in high-gain photorefractive materials.

The correct determination of the spatial phase shift ø(p) in photorefractive materials is crucial to the proper characterization of novel materials. It is shown that the grating translation techniques commonly used for the measurement of ø(p) need to be reevaluated for high-gain materials. Strong energy and phase coupling leads to nonuniform slanted gratings, which result in an apparent dependence of the phase shift of the beam ratio and the optical polarization. A revised theory is presented, and analytical solutions are obtained for the special case of ø(p)?pi/2 . Numerical solutions for arbitrary ø(p) are in good agreement with measurements in a photorefractive polymer.

Convolution-kernel-based optimal trade-off filters for optical pattern recognition.

An architecture for the implementation of optical pattern recognition is proposed that makes use of convolution-kernel-based optimal trade-off filters to allow for an increased speed of operation and filter storage capability. The derivation of these new convolution-kernel-based optimal trade-off filters is presented, and their noise robustness and discrimination capabilities are discussed.

High-frequency resonances in photorefractive crystals.

Two-wave mixing in photorefractive materials is investigated for the case of applied dc electric fields and large detuning frequencies and for high-frequency alternating electric fields. The appearance of high-frequency resonances is demonstrated.

Characterization of regulatory T-cell responses in humans induced by the P. Falciparum blood stage antigen Pf155/RESA.

T-cells have a major role both as helper cells for efficient antibody production and as inducers and effector cells in antibody-independent malaria immunity. Thus, antigens to be included into a subunit vaccine must contain T-cell epitopes to become effectively immunogenic. The P. falciparum blood stage vaccine antigen Pf155/RESA has been shown to contain T-helper epitopes inducing T-dependent anti-malarial antibodies in vitro. We have also shown that synthetic peptides representing sequences from the amino-acid repeat regions of Pf155/RESA stimulate T-cells from P. falciparum primed donors to proliferate, to release IFN-gamma and/or IL-4. In individual donors there was no correlation between these different activities. Rather, they were frequently negatively associated. However, IL-4 secretion could be induced in T-cells from donors who had elevated concentrations of serum antibodies to the same peptide as used for T-cell activation. Taken together the results support the occurrence of malaria-specific CD4+ T-cell subsets (e.g. TH1 and TH2) in humans similar to what has been found in mice and suggest the involvement of TH2-type helper cells in the induction of some important P. falciparum specific antibodies. CD4+ T-cells recognize the antigen in the context of MHC class II molecules. However, in human outbred populations no consistent MHC restrictions of anti-Pf155/RESA immune responses could be demonstrated. This is not surprising in view of the extensive polymorphism of the HLA system. Neither were there any obvious MHC class II restrictions seen when antibody- and t-cell responses were measured in naturally primed monozygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of subharmonics on two-wave gain in Bi(12)SiO(20) under alternating electric fields.

It is demonstrated that the emergence of subharmonics during two-wave mixing in a Bi(12)SiO(20) photorefractive crystal under applied alternating electric fields will markedly reduce two-wave gain. The repetition frequency at which the observed drop in two-wave gain appears is correlated with threshold conditions for the subharmonic instability for a wide range of experimental parameters.

Construction of a multidimensional scale of job satisfaction.

A comprehensive, multidimensional scale measuring job satisfaction was constructed for use in a major project concerned with personnel recruitment and retention of health professionals. 11 dimensions relating to opinions of immediate supervisors, physical working conditions, satisfaction with coworkers and with pay, aspects related to promotion and work motivation, are identified. These dimensions are shown to distinguish among health professionals on sex and between locations and different occupations. The scale also has high internal validity, producing a multiple R of .78 with over-all job satisfaction.

Explants of human oral epithelium exposed to viruses and cancer chemotherapeutics.

Cultures of proliferating epithelial cells were established from explants of normal human oral epithelium from healthy young volunteers. The epithelial cells were found permissive for herpes simplex virus type 1 and type 2, coxsackie virus A-4 and A-16, adenovirus type 5, measles vaccine, rubella and influenza type A virus-. Medium from DEAE-pretreated epithelial cultures infected with two subtypes of human immunodeficiency virus-1 showed an increasing content of virusprotein with time by antigen ELISA testing. In contrast there was no evidence of infection with coxsackie virus type B-2, cytomegalovirus, Epstein-Barr virus and varicella zoster virus. Treatment of the epithelial cells with a non-cytotoxic dose of cancer chemotherapeutic prior to or after infection with coxsackie virus A-4 or herpes simplex virus type 1 influenced the virus production dependent on both compound, mode of application, and virus. Adriamycin (doxorubicin) in low dose was found to stimulate the production of the two viruses.

Effect of folic acid on human oral epithelium in vitro.

The cytomorphological effects of folic acid were studied using in vitro established human oral epithelium. It was demonstrated that a concentration twice that used clinically (200 micrograms/ml) did not induce marked cytotoxic reaction in the cultured cells. The most pronounced changes were observed in cultures exposed to 200 micrograms/ml folic acid both in primary culture and subculture. The cultures displayed areas of degenerating cells showing oedema and increased translucency of the cytoplasm, flattened cells with distinct tonofilaments and atypical mitotic figures. Identical changes were found in cultures exposed to 50 and 100 micrograms/ml folic acid but to a lesser extent than in 200 micrograms/ml. These changes indicated that folic acid increased the number of cells undergoing terminal differentiation. From this study we suggested that folic acid when applied topically may play a role in local stimulation of epithelial cell differentiation leading to enhanced healing of oral ulcers.

Behavior of in vitro grown normal human mucosal epithelial cells and tumorigenic rat cells inoculated into nude mice.

The present study describes the behavior of in vitro grown normal human oral mucosal epithelial cells and that of a tumorigenic epithelial cell line following subcutaneous inoculation into nude mice. A successful recovery of viable human epithelial cell inocula was seen in 25-90% of mice and there was no improvement in recovery rates after addition of fibroblasts. These inocula resulted in cyst formation lined by a 2-6 cell layer unkeratinized squamous epithelium without rete ridges. There was no increase in recovery rate or size of cysts when coinoculated with fibroblasts. The tumorigenic cell inocula were successfully recovered in all cases. Tumors established from these inocula had a low grade of differentiation and were without signs of metastasis. Inocula of tumorigenic cells showed an increased size after addition of fibroblasts to the inocula. The model may be useful in studies of interactions between inoculations of heterologous normal and pathologic cells as well as in studies of differentiation of carcinogen-treated epithelial cells.

Growth of stratified squamous epithelium on reconstituted extracellular matrices: long-term culture.

Oral keratinocytes grown at an air-liquid interface on stabilized matrices of collagen or a basement membrane exhibit a pattern of tissue organization more similar to the parent tissue than the same cells cultured conventionally. An orderly sequence of cell migration and differentiation is maintained, and the full complement of terminally differentiated cells is retained on the surface of the culture for up to 65 days following subculture. The pattern of histodifferentiation of cultured stratified squamous epithelium differs according to the matrix upon which it is grown. Pliant, fine meshed gels of type III collagen are corrugated by the cultured keratinocytes with adjustments occurring in the various suprabasal cell strata that result in the retention of a flat stratum corneum. Such pliant gels can be stabilized by pouring a supporting underlayer of coarse type I guinea pig collagen. Keratinocytes grown directly on the irregular surface of guinea pig type I collagen migrate into spaces between collagen fibrillar bundles and aberrantly keratinize 20-30 days following subculture. Keratinocytes grown on a basement membrane do not aberrantly keratinize, suggesting that contact with a basement membrane may suppress signals for keratinocyte differentiation. Keratinocytes also form hemidesmosomes opposite a basement membrane but not opposite collagen fibrils. The keratin pattern of oral keratinocytes cultured in different configurations does not change; a finding that indicates that a greater degree of tissue organization does not automatically result in the synthesis of keratins more characteristic of upper cell strata or cornified cells in the native tissue.

Antagonistic effect of selenite on tumor promoter induced cell proliferation in cultures of rat tongue epithelium.

In cultures of rat tongue epithelial cells, cell proliferation following incubation with different doses of the potent tumor promoter TPA has been studied by using a stathmokinetic method counting colchicine arrested metaphases. It was demonstrated that 24 h incubation with concentrations higher than 5 ng TPA/mL medium caused inhibition, whereas below 5 ng TPA/mL medium caused stimulation of the mitotic activity reaching a maximum around 30 h from the start of the incubation period. Based on the evidence of the anticarcinogenic effect of selenium in several animal models, experiments have been performed elucidating the influence of an atoxic dose (1/1.000.000M) of selenite on the observed TPA-induced cell proliferation. Our results indicate that addition to the culture medium of an atoxic dose of selenite, not affecting the mitotic activity of control cultures, inhibits the TPA-induced stimulation of cell proliferation.

The growth and structure of human oral keratinocytes in culture.

Human keratinocytes derived from explants of cheek (buccal) mucosa grow vigorously in culture and can be subcultivated twice. The structure of the oral keratinocytes in vitro is the same in primary cultures and subcultures. The cells stratify, are characterized by well-developed tonofibrillar-desmosomal complexes, and rarely exhibit signs of terminal differentiation. Unique features of the culture system that favor keratinocyte growth are: incubation at 34 degrees C, inclusion of 0.5% dimethyl sulfoxide in the culture medium, and initiating subcultures as 5.0 mm colonies containing 100,000/20 microliter of medium. One primary culture can yield 6 first-passage subcultures, which subsequently achieve confluence in 10-12 days. Such cultures are a useful source of human keratinocytes that stratify but generally do not undergo terminal differentiation.

Herpes simplex virus-induced changes of the keratin type intermediate filament in rat epithelial cells.

Herpes simplex virus type 1 (HSV-1) infection of human fibroblast cells grown in culture induces reorganization of the cytoskeleton fibrillar structures. Normal transport and insertion of HSV glycoproteins into the plasma membrane of the cells depend on the integrity of the microtubules. The natural host cells for HSV are epithelial cells, and an epithelial cell line established from rat palate was used in the present study. The effect of virus on the structure of the intermediate filaments and especially on the keratin proteins was studied. Two-dimensional gel electrophoresis of total cell extracts identified in uninfected cells two major acidic keratin proteins with apparent molecular weights of 44,000 (44K) and 48K (pI 5.45 to 5.30, 5.50 to 5.35). A new keratin protein of 46K (pI 5.40 to 5.25) appeared in infected cells between 8 h and 12 h post-infection. Pulse-chase experiments identified the 46K protein as a processed form of the 48K keratin component, which was also cleaved in uninfected cells grown in the presence of cycloheximide. Partial proteolysis of the 46K and 48K keratins with Staphylococcus aureus V8 protease showed that the 48K and the 46K proteins differed in only one oligopeptide. The significance of the changed keratin composition of HSV-infected cells is discussed.

Chemically unrelated tumor promoters induce identical morphological changes in cultured rat oral epithelium.

By use of phase contrast microscopy, transmission and scanning electron microscopy the cytomorphological effects of different known tumor promoters (TPA, teleocidin, mezerein and anthralin) were studied and compared to the cytomorphological effects of a variety of non- or weak promoting irritants (ethylphenylpropiolate (EPP), phorbol, acetone, ethanol and dimethyl sulfoxide (DMSO]. The studies were conducted in cultures of stratifying rat tongue epithelial cells. It was demonstrated that the tumor promoters induce characteristic cytomorphological alterations, the most striking changes being elongation of the cells and formation of long cytoplasmic extensions together with induction of so-called "dark cells". The non-promoting irritants exerted well-known cytotoxic reactions like cell rounding and cell sloughing. It is suggested that the characteristic tumor promotor induced cytomorphological effects partly reflects a block of the intercellular communication and thus should be paid more attention as an important characteristic event among the pleiotropic effects exerted by tumor promoters.

Metabolism of benzo[a]pyrene by cultured rat and human buccal mucosa cells.

Primary cultures of epithelial and fibroblast cells derived from human oral mucosa were studied for the ability to activate a tobacco smoke carcinogen, benzo[a]pyrene (BP). The cells were exposed to benzo[a]pyrene for 18 h. The cell-free medium was extracted with ethylacetate/acetone, and high-pressure liquid chromatography analysis of this fraction revealed that BP tetrols and diols were the major metabolites formed by both epithelial and fibroblast cells. However, the epithelial cells had a much higher rate of biotransformation of BP as measured by binding to cellular DNA. The mean binding level to human buccal mucosal DNA was among the highest observed in stratified human epithelia. The major BP-DNA adduct was formed by the reaction of the 'bay-region' BP diolepoxide with the exocyclic 2-amino group in guanine. In contrast to human cells, BP phenols and BP 9,10-diol were the major metabolites produced by primary epithelial and fibroblast cells derived from rat buccal mucosa. The DNA binding levels of BP in the two rat cell types were identical, and the binding level was several-fold lower than in the human epithelial cells. When an established rat tongue epithelial cell line (RTE 2) was treated with polycyclic aromatic hydrocarbons--BP and 7,12-dimethylbenz[a]-anthracene--a slight toxic effect was observed. Our results indicate that primary cultures of oral mucosa are able to metabolize BP into its ultimate carcinogenic form at a rate similar to or higher than other potential target tissues for BP-induced carcinogenesis.