Reducing the foreign body response on human cochlear implants and their materials in vivo with photografted zwitterionic hydrogel coatings

The foreign body response to implanted materials often complicates the functionality of sensitive biomedical devices. For cochlear implants, this response can reduce device performance, battery life and preservation of residual acoustic hearing. As a permanent and passive solution to the foreign body response, this work investigates ultra-low-fouling poly(carboxybetaine methacrylate) (pCBMA) thin film hydrogels that are simultaneously photo-grafted and photo-polymerized onto polydimethylsiloxane (PDMS). The cellular anti-fouling properties of these coatings are robustly maintained even after six-months subcutaneous incubation and over a broad range of cross-linker compositions. On pCBMA-coated PDMS sheets implanted subcutaneously, capsule thickness and inflammation are reduced significantly in comparison to uncoated PDMS or coatings of polymerized poly(ethylene glycol dimethacrylate) (pPEGDMA). Further, capsule thickness is reduced over a wide range of pCBMA cross-linker compositions. On cochlear implant electrode arrays implanted subcutaneously for one year, the coating bridges over the exposed platinum electrodes and dramatically reduces the capsule thickness over the entire implant. Coated cochlear implant electrode arrays could therefore lead to persistent improved performance and reduced risk of residual hearing loss. More generally, the in vivo anti-fibrotic properties of pCBMA coatings also demonstrate potential to mitigate the fibrotic response on a variety of sensing/stimulating implants. STATEMENT OF SIGNIFICANCE: This article presents, for the first time, evidence of the in vivo anti-fibrotic effect of zwitterionic hydrogel thin films photografted to polydimethylsiloxane (PDMS) and human cochlear implant arrays. The hydrogel coating shows no evidence of degradation or loss of function after long-term implantation. The coating process enables full coverage of the electrode array. The coating reduces fibrotic capsule thickness 50-70% over a broad range of cross-link densities for implantations from six weeks to one year.

Onset of nut allergy in a pediatric cohort: clinical and molecular patterns. AFRUSEN study

Nut Allergy, Peanut, Walnut, Allergy Onset, Sensitization Profile, Component Resolved Diagnosis, Anaphylaxis, Food Allergy.

In situ Near-Ambient Pressure X-ray Photoelectron Spectroscopy Reveals the Influence of Photon Flux and Water on the Stability of Halide Perovskite

For several years, scientists have been trying to understand the mechanisms that reduce the long-term stability of perovskite solar cells. In this work, we examined the effect of water and photon flux on the stability of CH3 NH3 PbI3 perovskite films and solar cells using in situ near-ambient pressure X-ray photoelectron spectroscopy (NAP-XPS), field emission scanning electron microscopy (FESEM), and current density-voltage (J-V) characterization. The used amount of water vapor (up to 1 mbar) had a negligible impact on the perovskite film. The higher the photon flux, the more prominent were the changes in the NAP-XPS and FESEM data; also, a faster decline in power conversion efficiency (PCE) and a more substantial hysteresis in the J-V characteristics were observed. Based on our results, it can be concluded that the PCE decrease originates from the creation of Frenkel pair defects in the perovskite film under illumination. The stronger the illumination, the higher the number of Frenkel defects, leading to a faster PCE decline and more substantial hysteresis in the J-V sweeps.

Oral Immunotherapy for Food Allergy: A Spanish Guideline. Immunotherapy Egg and Milk Spanish Guide (ITEMS Guide). Part I: Cow Milk and Egg Oral Immunotherapy: Introduction, Methodology, Rationale, Current State, Indications, Contraindications, and Oral Immunotherapy Build-up Phase

BACKGROUND AND OBJECTIVE

Cow milk and egg are the most frequent causes of food allergy in the first years of life. Oral immunotherapy (OIT) has been investigated as an alternative to avoidance diets. No clinical practice guidelines on the management of OIT with milk and egg are currently available. Objectives: To develop clinical guidelines for OIT based on available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published between 1984 and June 2016, doctoral theses published in Spain, summaries of communications at scientific meetings (SEAIC, SEICAP, EAACI, and AAAAI), and the consensus of opinion established by a group of experts from the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations were established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of adverse reactions.

CONCLUSIONS

Clinical practice guidelines based on the consensus reached between Spanish experts are presented for the management of OIT with milk and egg.

Profilin, a Change in the Paradigm

Profilin is a protein that is present in all eukaryotic cells and is responsible for cross-reactivity between pollen, latex, and plant foods. It has been classically acknowledged as a minor or nearly irrelevant allergen, although recent data are changing this conception. The objective of this manuscript is to provide a comprehensive review of published data on the role of this ubiquitous allergen in pollen, latex, and plant food allergy. The patterns of recognition of this minor allergen follow a north-south gradient. Although present in all pollens and vegetables, profilin is significantly associated with allergy to grass pollen and to Cucurbitaceae fruits. Heb v 8, the latex profilin, is usually a marker of profilin allergy in plant food-allergic patients, although it has no clinical relevance in latex allergy. Sensitization to profilin jeopardizes the diagnosis of pollen allergy and selection of immunotherapy, and although component-resolved diagnosis can identify its impact, there are no tailored treatments available. In recent years, several new publications have shown how profilin should be taken into account and, under certain circumstances, considered a marker of severity, an allergen capable of inducing respiratory symptoms, and, in its natural purified form, a potential candidate for etiological treatment of food allergy. Current data on profilin strongly support the need for a shift in the previously accepted paradigm for this allergen. More research should be done to assess the real clinical impact of sensitization in specific populations and to develop therapeutic strategies.

Oral immunotherapy for food allergy: A Spanish guideline. Immunotherapy egg and milk Spanish guide (items guide). Part I: Cow milk and egg oral immunotherapy: Introduction, methodology, rationale, current state, indications contraindications and oral immunotherapy build-up phase

INTRODUCTION

Cow's milk and egg are the most frequent causes of food allergy in the first years of life. Treatments such as oral immunotherapy (OIT) have been investigated as an alternative to avoidance diets. No clinical practice guides on the management of OIT with milk and egg are currently available.

OBJECTIVES

To develop a clinical guide on OIT based on the available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published in the period between 1984 and June 2016, Doctoral Theses published in Spain, and summaries of communications at congresses (SEAIC, SEICAP, EAACI, AAAAI), with evaluation of the opinion consensus established by a group of experts pertaining to the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations have been established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of suffering adverse reactions.

CONCLUSIONS

A clinical practice guide is presented for the management of OIT with milk and egg, based on the opinion consensus of Spanish experts.

Oral Immunotherapy for Food Allergy: A Spanish Guideline. Egg and Milk Immunotherapy Spanish Guide (ITEMS GUIDE). Part II: Maintenance Phase of Cow Milk (CM) and Egg Oral Immunotherapy (OIT), Special Treatment Dosing Schedules. Models of Dosing Schedules of OIT With CM and Egg

BACKGROUND AND OBJECTIVE

Cow milk and egg are the most frequent causes of food allergy in the first years of life. Oral immunotherapy (OIT) has been investigated as an alternative to avoidance diets. No clinical practice guidelines on the management of OIT with milk and egg are currently available. Objectives: To develop clinical guidelines for OIT based on available scientific evidence and the opinions of experts.

METHODS

A review was made of studies published between 1984 and June 2016, doctoral theses published in Spain, summaries of communications at scientific meetings (SEAIC, SEICAP, EAACI, and AAAAI), and the consensus of opinion established by a group of experts from the scientific societies SEICAP and SEAIC.

RESULTS

Recommendations were established regarding the indications, requirements and practical aspects of the different phases of OIT, as well as special protocols for patients at high risk of adverse reactions.

CONCLUSIONS

Clinical practice guidelines based on the consensus reached between Spanish experts are presented for the management of OIT with milk and egg.

Early sustained unresponsiveness after short-course egg oral immunotherapy: a randomized controlled study in egg-allergic children

BACKGROUND

No studies have evaluated the potential of egg oral immunotherapy (egg-OIT) to induce sustained unresponsiveness after discontinuing therapy following short-term treatments.

OBJECTIVE

We assessed the efficacy of short-course egg-OIT to induce sustained unresponsiveness.

METHODS

Sixty-one egg-allergic children, 5 to 17 years old, with positive double-blind placebo-controlled food challenge (DBPCFC) to dehydrated egg white (EW) were randomized to receive egg-OIT (OITG) for 3 months (maintenance dose one undercooked egg every 48 hours) or to continue egg avoidance diet (control group, CG) for 4 months. Children who completed egg-OIT avoided egg for 1 month. At 4 months, both groups underwent a DBPCFC. OITG participants who passed this challenge were instructed to add egg to their diet ad libitum. Immune markers were studied at different time points.

RESULTS

Ninety-three percent (28/30) of OITG children were desensitized in a median of 32.5 days (IQR, 14 days). At 4 months, 1/31 (3%) in CG passed DBPCFC and 11/30 (37%) of OITG (95% CI, 14 to 51%; P = 0.003), all of them were consuming egg at 36 months. A decrease in EW, OVA and OVM skin test results and OVA-specific IgE (sIgE) levels was observed on OITG at 4 months (P = 0.001). EW-, OVA- and OVM-sIgE levels prior to the start of egg avoidance diet were lower in OITG children who passed DBPCFC at 4 months than in those who did not pass it. EW- and OVM-sIgE showed the best diagnostic performance in predicting DBPCFC result at 4 months. Levels above optimal EW-sIgE cut-off of 7.1 kU/L indicated 90% probability of failing DBPCFC.

CONCLUSION

This is the first demonstration of sustained unresponsiveness with a three-month egg-OIT protocol. Almost all treated subjects were desensitized and 37% achieved sustained unresponsiveness. EW-sIgE levels at the end of treatment predicted sustained unresponsiveness. This protocol shows a new approach to OIT for egg-allergic children.

Diffusion in an expanding medium: Fokker-Planck equation, Green's function, and first-passage properties

We present a classical, mesoscopic derivation of the Fokker-Planck equation for diffusion in an expanding medium. To this end, we take a conveniently generalized Chapman-Kolmogorov equation as the starting point. We obtain an analytical expression for the Green's function (propagator) and investigate both analytically and numerically how this function and the associated moments behave. We also study first-passage properties in expanding hyperspherical geometries. We show that in all cases the behavior is determined to a great extent by the so-called Brownian conformal time τ(t), which we define via the relation τ[over ̇]=1/a^{2}, where a(t) is the expansion scale factor. If the medium expansion is driven by a power law [a(t)∝t^{γ} with γ>0], then we find interesting crossover effects in the mixing effectiveness of the diffusion process when the characteristic exponent γ is varied. Crossover effects are also found at the level of the survival probability and of the moments of the first passage-time distribution with two different regimes separated by the critical value γ=1/2. The case of an exponential scale factor is analyzed separately both for expanding and contracting media. In the latter situation, a stationary probability distribution arises in the long-time limit.

Optical pseudomotors for soft x-ray beamlines

Optical elements of soft x-ray beamlines usually have motorized translations and rotations that allow for the fine alignment of the beamline. This is to steer the photon beam at some positions and to correct the focus on slits or on sample. Generally, each degree of freedom of a mirror induces a change of several parameters of the beam. Inversely, several motions are required to actuate on a single optical parameter, keeping the others unchanged. We define optical pseudomotors as combinations of physical motions of the optical elements of a beamline, which allow modifying one optical parameter without affecting the others. We describe a method to obtain analytic relationships between physical motions of mirrors and the corresponding variations of the beam parameters. This method has been implemented and tested at two beamlines at ALBA, where it is used to control the focus of the photon beam and its position independently.

Comprehensive Review of Current Knowledge on Egg Oral Immunotherapy

Oral immunotherapy (OIT) is an attractive strategy for active treatment of IgE-mediated food allergy. Multiple egg OIT studies have been published to date, but many are uncontrolled. Furthermore, interpretation of the results is difficult because of significant heterogeneity in design, aims, and population. Most studies have demonstrated the potential of egg OIT to induce desensitization, albeit to different extents (0%-100% of patients). However, few studies have explored the capacity of OIT to maintain tolerance, that is, enabling the patient to continue consuming egg after suspension of therapy. Nowadays, 28% to 75% of patients maintain tolerance after 1 to 3 months of their elimination diet. Adverse effects are the main drawback of this treatment, which is still not recommended in routine practice. Adverse reactions are not reported homogeneously, with the result that it is difficult to properly assess outcomes. The overall impression is that adverse reactions affect most patients and tend to be frequent, although of mild to moderate severity. Nevertheless, severe events such as anaphylaxis or eosinophilic esophagitis may also occur. Immunological changes resulting from egg OIT, for example, the decrease in the size of the skin prick test wheal and the levels of egg white sIgE and a significant early increase in egg white sIgG4, have been reported. Several areas of egg OIT remain unclear, including patient selection, materials used, dosing schedule, treatment duration, long-term maintained effectiveness, requirements for implementation in clinical practice, influence on quality of life, and cost-effectiveness of treatment. In this review, we provide an in-depth examination of methodological differences between studies in order to understand the diversity in the efficacy and safety results of the procedures used in egg OIT.

Oral immunotherapy in children with IgE-mediated wheat allergy: outcome and molecular changes

BACKGROUND

IgE-mediated wheat allergy affects around 0.5% of the population, and current management is based on avoidance. We propose an active intervention to promote tolerance in wheat-allergic children.

OBJECTIVES

To investigate the efficacy and safety of an oral immunotherapy (OIT) protocol with wheat to treat IgE-mediated wheat-allergic children.

METHODS

Six wheat allergic patients assessed in a double-blind, placebo-controlled food challenge (DBPCFC) underwent wheat OIT with an up-dosing phase until 100 g of wheat was tolerated, followed by a 6-month maintenance phase. Tolerance to rye and oat was evaluated, as were specific IgE (sIgE) to wheat and other cereals and sIgE, slgG4, and sIgG1 to a panel of wheat proteins (alpha-amylase and trypsin inhibitors, wheat lipid transfer proteins, gliadins, and glutenins).

RESULTS

Threshold doses in the wheat DBPCFC ranged from 6.6 g to 96.6 g. Five out of 6 (83%) patients successfully finished the up-dosing phase in 3 to 24 days; after a 6-month maintenance phase, all the patients maintained good tolerance of 100 g of wheat daily. Only 6.25% of doses in the up-dosing phase elicited mild adverse reactions. All 5 patients who successfully finished the up-dosing phase tolerated rye after OIT, and all but 1 tolerated oat as well. The median baseline wheat sIgE was 47.5 kU(A)/L, increasing to 84.55 kU(A)/L after up-dosing and decreasing to 28.75 kU(A)/L after 6 months of follow-up. None of the patients showed sIgE to 5-omega-gliadin, but alpha-amylase inhibitors were recognized by all patients. Specific IgG4 and sIgG1 increased in all patients.

CONCLUSIONS

Our wheat OIT protocol was safe, efficient, and rapid. In our population, alpha-amylase was the major allergen.

Allopregnanolone and puberty: modulatory effect on glutamate and GABA release and expression of 3α-hydroxysteroid oxidoreductase in the hypothalamus of female rats

The hypothalamic release of glutamate and GABA regulates neurosecretory functions that may control the onset of puberty. This release may be influenced by neurosteroids such as allopregnanolone. Using superfusion experiments we examined the role of allopregnanolone on the K(+)-evoked and basal [(3)H]-glutamate and [(3)H]-GABA release from mediobasal hypothalamus and anterior preoptic area in prepubertal, vaginal opening and pubertal (P) rats and evaluated its modulatory effect on GABAA and NMDA (N-methyl-d-aspartic acid) receptors. Also, we examined the hypothalamic activity and mRNA expression of 3α-hydroxysteroid oxidoreductase (3α-HSOR) - enzyme that synthesizes allopregnanolone - using a spectrophotometric method and RT-PCR, respectively. Allopregnanolone increased both the K(+)-evoked [(3)H]-glutamate and [(3)H]-GABA release in P rats, being the former effect mediated by the modulation of NMDA receptors - as was reverted by Mg(2+) and by the NMDA receptor antagonist AP-7 and the latter by the modulation of NMDA and GABAA receptors - as was reverted by Mg(2+) and the GABAA receptor antagonist bicuculline. The neurosteroid also increased the basal release of [(3)H]-glutamate in VO rats in an effect that was dependent on the modulation of NMDA receptors as was reverted by Mg(2+). On the other hand we show that allopregnanolone reduced the basal release of [(3)H]-GABA in P rats although we cannot elucidate the precise mechanism by which the neurosteroid exerted this latter effect. The enzymatic activity and the mRNA expression of 3α-HSOR were both increased in P rats regarding the other two studied stages of sexual development. These results suggest an important physiological function of allopregnanolone in the hypothalamus of the P rat where it might be involved in the 'fine tuning' of neurosecretory functions related to the biology of reproduction of the female rats.

PP003. Antagonism in A2A and A2B adenosine receptor on fetal endothelium proliferation involves a nitric oxide-depended intracellular pathway in early and late-onset pre-eclampsia

INTRODUCTION

Adenosine A2A and A2B receptor intracellular pathway is associated with either increasing endothelial nitric oxide (NO) synthase (eNOS) expression or eNOS activation (i.e., tyrosine 1177 phosphorylation); a mechanism linked to pro or anti-proliferative effects depending of the cell type. However, there are no reports in pre-eclampsia.

OBJECTIVES

Investigate whether NO signaling pathway is involved in fetal endothelium proliferation induced by adenosine receptor activation in early and late-onset pre-eclampsia.

METHODS

Human umbilical vein endothelial cells (HUVEC) were isolated from normal (n=25), late-onset pre-eclampsia (n=11) and early-onset pre-eclampsia (n=22). Adenosine A2A and A2B expression was evaluated by immunocytochemistry and Western blot. Cell proliferation was analyzed using MTS-assay in absence or presence of non-selective adenosine receptor agonist (NECA 10μM), adenosine A2A receptor selective agonist (CGS-21680, 100nM), and/or the antagonists ZM-241385 (0-100μM) or MRS-1754 (0-1μM) for A2A and A2B receptors during 24h. In parallel experiments NOS inhibitor (L-NAME, 100μM) was used in co-incubation by either adenosine receptor agonist or antagonists. Nitrite concentration in the culture medium and protein nitration assessed by Western blot were measured in cells exposed to CGS-21680 (30min).

RESULTS

Early-onset pre-eclampsia was associated to low A2A (∼70%), but high (∼2-fold) A2B adenosine receptor protein abundance compared with normal or late-onset pre-eclampsia. Basally, HUVEC from early-onset showed a low (∼42%), whereas late-onset exhibited high proliferation (∼1.5-fold) compared with normal pregnancy. Cell proliferation was increased by CGS-21680 (∼2-fold) in late-onset or normal pregnancy and ∼5-fold in early-onset pre-eclampsia compared with respective control. NECA increased cell proliferation only in normal cells. Stimulatory effect of CGS-21680, was inhibited by ZM-241385 in normal pregnancies (Ki, 25nM) and late-onset (Ki 50nM) but not in early-onset (Ki ambiguous). Interestingly, MRS-1754 showed an increase in cell proliferation in a dose-response manner only in early-onset group. L-NAME partially blocked (∼25%) the stimulatory effect of CGS-21680 in late-onset and normal pregnancy. Interestingly, L-NAME revert the maximal stimulatory effect of MRS-1754 observed in early-onset. Total and phosphorylated eNOS protein was reduced (∼50%) in early-onset pre-eclampsia compared to late-onset or normal pregnancy. In turn, cells from late-onset pre-eclampsia exhibited high (∼2-fold) eNOS phosphorylation compared with normal pregnancy. In normal pregnancy, CGS-21680 (30min) increased (∼2-fold) the eNOS phosphorylation and nitrotyrosine formation, without changes in nitrite levels, but non-significant changes were observed in early or late-onset pre-eclamptic cells.

CONCLUSION

Fetal endothelium from early-onset exhibits a predominant anti-proliferative effect mediated by adenosine A2B receptors activation, whereas the stimulatory effect of adenosine A2A receptors prevails in cells from late-onset pre-eclampsia. Both pro and anti-proliferative effects seem mediated by a nitric oxide-depended intracellular pathway. Supported by FONDECYT 1100684, Conicyt Anillo ACT73.

The placenta in preeclampsia

The root cause of preeclampsia is the placenta. Preeclampsia begins to abate with the delivery of the placenta and can occur in the absence of a fetus but with the presence of trophoblast tissue with hydatidiform moles. In view of this, study of the placenta should provide insight into the pathophysiology of preeclampsia. In this presentation we examine placental pathological and pathophysiological changes with preeclampsia and fetal growth restriction (FGR). It would seem that this comparison should be illuminating as both conditions are associated with similarly abnormal placentation yet only in preeclampsia is there a maternal pathophysiological syndrome. Similar insights about early and late onset preeclampsia should also be provided by such information.We report that the placental abnormalities in preeclampsia are what would be predicted in a setting of reduced perfusion and oxidative stress. However, the differences from FGR are inconsistent. The most striking differences between the two conditions are found in areas that have been the least studied. There are differences between the placental findings in early and late onset preeclampsia but whether these are qualitative, indicating different diseases, or simply quantitative differences within the same disease is difficult to determine.We attempt to decipher the true differences, seek an explanation for the disparate results and provide recommendations that we hope may help resolve these issues in future studies.

Pattern formation in stromatolites: insights from mathematical modelling

To this day, computer models for stromatolite formation have made substantial use of the Kardar-Parisi-Zhang (KPZ) equation. Oddly enough, these studies yielded mutually exclusive conclusions about the biotic or abiotic origin of such structures. We show in this paper that, at our current state of knowledge, a purely biotic origin for stromatolites can neither be proved nor disproved by means of a KPZ-based model. What can be shown, however, is that whatever their (biotic or abiotic) origin might be, some morphologies found in actual stromatolite structures (e.g. overhangs) cannot be formed as a consequence of a process modelled exclusively in terms of the KPZ equation and acting over sufficiently large times. This suggests the need to search for alternative mathematical approaches to model these structures, some of which are discussed in this paper.

Oral desensitization as a useful treatment in 2-year-old children with cow's milk allergy

BACKGROUND

Limited published evidence shows oral desensitization to be a potential intervention option for cow's milk protein (CMPs) allergy.

OBJECTIVE

The aim of this study was to evaluate the safety and efficacy of oral desensitization in 2-year-old children with cow's milk allergy, as a treatment alternative to elimination diet.

METHODS

A total of 60 children aged 24-36 months with IgE-mediated allergy to CMPs were included in this multi-center study and were randomized into two groups. Thirty children (group A: treatment group) began oral desensitization immediately, whereas the remaining 30 (group B: control group) were kept on a milk-free diet and followed-up for 1 year.

RESULTS

After 1-year follow-up period, 90% of the children in group A had become completely tolerant vs. 23% of the children in group B. In group A, cow's milk skin reactivity and serum-specific IgE to milk and casein decreased significantly from the initial assessment, whereas group B showed no significant change after 1 year of follow-up. Twenty-four patients (80%) developed some reaction during the treatment period: 14 children developed moderate reaction (47%) and 10 mild reaction (33%). The most common manifestations were urticaria-angioedema, followed by cough.

CONCLUSIONS AND CLINICAL RELEVANCE

In this study, oral desensitization was found to be effective in a significant percentage of 2-year-old children with cow's milk allergy. Oral desensitization appears to be efficacious as an alternative to elimination diet in the treatment of 2-year-old children with cow's milk allergy. The side-effect profile appears acceptable but requires further study.

IFPA Meeting 2010 Workshop Report I: Immunology; ion transport; epigenetics; vascular reactivity; epitheliochorial placentation; proteomics

Workshops are an important part of the IFPA annual meeting. At IFPA Meeting 2010 there were twelve themed workshops, six of which are summarized in this report. 1. The immunology workshop focused on normal and pathological functions of the maternal immune system in pregnancy. 2. The transport workshop dealt with regulation of ion and water transport across the syncytiotrophoblast of human placenta. 3. The epigenetics workshop covered DNA methylation and its potential role in regulating gene expression in placental development and disease. 4. The vascular reactivity workshop concentrated on methodological approaches used to study placental vascular function. 5. The workshop on epitheliochorial placentation covered current advances from in vivo and in vitro studies of different domestic species. 6. The proteomics workshop focused on a variety of techniques and procedures necessary for proteomic analysis and how they may be implemented for placental research.

Eosinophilic esophagitis, celiac disease, and immunoglobulin E-mediated allergy in a 2-year-old child

Celiac disease, eosinophilic esophagitis, and urticaria are 3 manifestations of food allergy with different pathogenic mechanisms. We report the case of a 2-year-old child with digestive symptoms, slow growth, and severe asthma. The results of skin prick tests were positive to several foods. Endoscopy revealed eosinophilic esophagitis and celiac disease. Treatment consisted of a gluten-free diet and a 1-month course of oral corticosteroids. Endoscopy and biopsy findings were normal at 5 years of age. A gluten-free diet is the basis of treatment of celiac disease, but the role of an elimination diet in eosinophilic esophagitis is not well established. Our patient also developed urticaria when exposed to milk and egg.We present, to our knowledge, the first report of a patient with celiac disease, eosinophilic esophagitis, and immediate-type immunoglobulin E-mediated food allergy.

Discretization-related issues in the Kardar-Parisi-Zhang equation: consistency, Galilean-invariance violation, and fluctuation-dissipation relation

In order to perform numerical simulations of the Kardar-Parisi-Zhang (KPZ) equation, in any dimensionality, a spatial discretization scheme must be prescribed. The known fact that the KPZ equation can be obtained as a result of a Hopf-Cole transformation applied to a diffusion equation (with multiplicative noise) is shown here to strongly restrict the arbitrariness in the choice of spatial discretization schemes. On one hand, the discretization prescriptions for the Laplacian and the nonlinear (KPZ) term cannot be independently chosen. On the other hand, since the discretization is an operation performed on space and the Hopf-Cole transformation is local both in space and time, the former should be the same regardless of the field to which it is applied. It is shown that whereas some discretization schemes pass both consistency tests, known examples in the literature do not. The requirement of consistency for the discretization of Lyapunov functionals is argued to be a natural and safe starting point in choosing spatial discretization schemes. We also analyze the relation between real-space and pseudospectral discrete representations. In addition we discuss the relevance of the Galilean-invariance violation in these consistent discretization schemes and the alleged conflict of standard discretization with the fluctuation-dissipation theorem, peculiar of one dimension.

Adenosine mediates transforming growth factor-beta 1 release in kidney glomeruli of diabetic rats

Up regulation of the transforming growth factor-beta 1 (TGF-beta1) axis has been recognized as a pathogenic event for progression of glomerulosclerosis in diabetic nephropathy. We demonstrate that glomeruli isolated from diabetic rats accumulate up to sixfold more extracellular adenosine than normal rats. Both decreased nucleoside uptake activity by the equilibrative nucleoside transporter 1 and increased AMP hydrolysis contribute to raise extracellular adenosine. Ex vivo assays indicate that activation of the low affinity adenosine A2B receptor subtype (A2BAR) mediates TGF-beta1 release from glomeruli of diabetic rats, a pathogenic event that could support progression of glomerulopathy when the bioavailability of adenosine is increased.

Inhibition of the intimal hyperplasia in an arterial autograft model by blockade of the N-terminal of the integrin beta3 subunit by monoclonal antibody P37

Myointima formation or intimal hyperplasia is a major undesirable problem at the anastomotic ends of narrow bore arterial autografts and in other arterial wall injuries, which often leads to late restenosis and thrombosis and whose pathogenesis is still not understood. Platelets are suspected to intervene at some stages of its development, together with endothelial and muscle cells, the extracellular matrix and, most probably, adhesion receptors. To ascertain whether and at what stage beta3 integrins are involved, a rat arterial autograft model was used, together with monoclonal antibody P37, which is directed to the sequence 101-109 of the beta3 subunit of the human platelet fibrinogen receptor (integrin alphaIIbbeta3) and inhibits platelet aggregation in vitro and acute thrombosis in vivo. Three groups of animals were used: group I underwent an arterial autograft of a 5-mm segment of the right common iliac artery; group II received, intravenously, a single dose (0.8 mg/kg) of P37 at 15 min before the graft implantation; and group III was treated as group II but a similar dose of antibody was additionally given on day 14 after the operation. Animals in each group were sacrificed on days 7, 14, 21, 30 and 50 after the operation, and the grafts were removed for light and electron microscopy observation and further time-dependent morphometric analysis. By day 14, group I autografts already showed intimal hyperplasia and secretory smooth muscle cells, while group II and II autografts presented only some degenerative changes in the medial layer, with no signs of hyperplasia. Intimal hyperplasia was observed on day 21 in group II and on day 30 in group III, although less pronounced than in the corresponding controls. However, by day 50, the three groups had the same thickness of myointima. The immunohistochemical determination of metalloproteases suggests no role for these enzymes in the immunoinhibition of myointima formation. We conclude that P37 inhibits the onset of the intimal hyperplasia in the arterial autografts and that this onset in treated animals seems to be related to the decay of the circulating antibody. Further work is required to decide whether a higher or longer presence of circulating P37 can definitively prevent the development of intimal hyperplasia, as well as to ascertain which cells and which beta3 integrin receptors intervene.

Reduced l-arginine transport and nitric oxide synthesis in human umbilical vein endothelial cells from intrauterine growth restriction pregnancies is not further altered by hypoxia

Intrauterine growth restriction (IUGR) is associated with chronic fetal hypoxia, altered placental vasodilatation and reduced endothelial nitric oxide synthase (eNOS) activity. In human umbilical vein endothelial cells (HUVEC) from pregnancies complicated with IUGR (IUGR cells) and in HUVEC from normal pregnancies (normal cells) cultured under hypoxia l-arginine transport is reduced; however, the mechanisms leading to this dysfunction are unknown. We studied hypoxia effect on l-arginine transport and human cationic amino acid transporters 1 (hCAT-1) expression, and the potential NO and protein kinase C alpha (PKCalpha) involvement. Normal or IUGR HUVEC monolayers were exposed (0-24h) to 5% O(2) (normoxia), and 1 or 2% O(2) (hypoxia). l-Arginine transport and hCAT-1 expression, phosphorylated and total PKCalpha or eNOS protein and mRNA expression were quantified. eNOS involvement was tested using a siRNA against eNOS (eNOS-siRNA) adenovirus. IUGR cells in normoxia or hypoxia, and normal cells in hypoxia exhibited reduced l-arginine transport, hCAT-1 expression, NO synthesis and eNOS phosphorylation at Serine(1177), effects reversed by calphostin C (PKC inhibitor) and S-nitroso-N-acetyl-l,d-penicillamine (SNAP, NO donor). However, N(G)-nitro-l-arginine methyl ester (l-NAME, NOS inhibitor) reduced hCAT-1 expression only in normal cells in normoxia. Increased Thr(638)-phosphorylated PKCalpha was exhibited by IUGR cells in normoxia or hypoxia and normal cells in hypoxia. The effects of hypoxia in normal cells were mimicked in eNOS-siRNA transduced cells; however, IUGR phenotype was unaltered by eNOS knockdown. Thus, IUGR- and hypoxia-reduced l-arginine transport could result from increased PKCalpha, but reduced eNOS activity leading to a lower hCAT-1 expression in HUVEC. In addition, IUGR endothelial cells are either not responsive or maximally affected by hypoxia. These mechanisms could be responsible for placental dysfunction in diseases where fetal endothelium is chronically exposed to hypoxia, such as IUGR.

Development and validation of a new Spanish instrument to measure health-related quality of life in patients with allergic rhinitis: the ESPRINT questionnaire

OBJECTIVES

To develop and validate an instrument to measure health-related quality of life (HRQOL) specific to patients with allergic rhinitis (AR) and primarily for use in Spanish and Spanish-speaking populations.

METHODS

An initial item pool was generated from literature review, focus groups with AR patients, and consultations with clinical experts. Item reduction was performed using clinimetric and psychometric approaches after administration of the item pool to 400 AR patients. The resulting instrument's internal consistency, test-retest (2-4 weeks) reliability, known groups and convergent validity, and sensitivity to change were tested in a longitudinal, observational, multicenter study in 210 AR patients who also completed the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ).

RESULTS

The new questionnaire took a mean (SD) of 7.1 (5.4) minutes to answer. Floor and ceiling effects were less than 15% on all dimensions. Cronbach's alpha values and intraclass correlation coefficient values for six of the sevendimensions and the overall score exceeded 0.70. Statistically significant differences (P < 0.01) were observed on all ESPRINT-28 dimensions and the overall score between patients with mild (mean overall score 1.97, SD 0.99), moderate (mean overall score 2.78, SD 0.88), and severe AR (mean overall score 3.89, SD 0.87). Patients with persistent AR had worse scores (P < 0.05) on all dimensions than patients with intermittent AR. Correlations between the ESPRINT-28 and the RQLQ were generally as expected. Effect sizes for score changes between the two study visits ranged from 0.96 to 1.76 for individual dimensions and the overall score.

CONCLUSIONS

This new, Spanish-developed instrument to measure HRQOL in AR patients has shown good reliability, validity, and sensitivity to change. It has also proved easy to use and administer.

Bronchial responsiveness to bakery-derived allergens is strongly dependent on specific skin sensitivity

BACKGROUND

Quantitative relationships between immunological reactivity, non-specific bronchial responsiveness and bronchial responsiveness to allergens have scarcely been investigated in occupational asthma.

METHODS

We assessed the above relationships in 24 subjects with baker's asthma. The skin endpoint titration to bakery allergens as a measure of immunological reactivity, together with the methacholine PC20 and allergen PC20 during early asthmatic reaction were determined.

RESULTS

All patients had positive skin tests to some bakery allergens (wheat and rye flour, soybean flour, fungal enzymes and egg white proteins) and bronchial hyperresponsiveness to methacholine. Specific inhalation challenge (SIC) tests were performed with aqueous allergen extracts of cereal flour (n = 14), soybean (n = 8), baking enzymes (n = 12), and egg white proteins (n = 8) in sensitized workers. A positive asthmatic reaction was observed in 84% of the inhalation challenges. SIC elicited isolated early asthmatic reactions in 62%, dual reactions in 32% and isolated late reactions in 5%. Multiple linear regression analysis showed allergen PC20 as a function of skin sensitivity to allergen and methacholine PC20, yielding the following highly significant regression formula: log-allergen PC20 = 0.18 + 0.99 log(skin sensitivity) + 0.343 log(methacholine PC20) (r = 0.89, P < 0.001). This formula predicted allergen PC20 to within one double concentration in 67%, to within two double concentrations in 85% and within three double concentrations in 97%.

CONCLUSION

The main determinant of bronchial responsiveness to allergen in patients with baker's asthma is the degree of sensitization to occupational allergens as determined by skin reactivity, modulated to a lesser extent by non-specific bronchial hyperresponsiveness.

Antithrombotic map of the N-terminal domain of the GPIIIa subunit of the human platelet fibrinogen receptor (GPIIb-IIIa) determined in vivo by monoclonal, immunochemical inhibition of acute arterial thrombosis

The inhibition of the platelet fibrinogen receptor, the glycoprotein IIb-IIIa (GPIIb-IIIa) or integrin alphaIIbbeta3, has recently became an accepted practice in clinical cardiology. The interest lies now in the improvement of the antithrombotic activity and the minimization of the secondary effects of the receptor inhibitors, by their evaluation in vivo in the different dynamic conditions and pathological states under which these inhibitors have to perform. In this paper, we functionally map in vivo the N-terminal domain of the GPIIIa subunit, using the antithrombotic activity of five murine monoclonal antibodies (mabs) (P37, P40, 95-1, P95-2 and P97), all of them inhibitors of platelet aggregation in vitro and directed to this ligand binding domain of the human fibrinogen receptor. Competition experiments have shown that these mabs bind with high affinity (5-7 nM) and compete very strongly among themselves for binding to human resting platelets, except P40, which neither binds nor competes. These antibodies were assayed in a dog model of acute thrombosis in the carotid artery, which were induced 15 min after their intravenous administration (0.8 mg/kg). The antithrombotic activity was quantified by the measurement of the [111In]oxine-labelled platelet deposition at the site of the arterial lesion and was expressed as the percentage of the total circulating platelets. Antibody P37, directed to the GPIIIa 101-109 sequence, decreased the platelet deposition 630-fold with respect to control animals. P95-2, P97 and P95-1 decreased the platelet deposition 160-, 32- and 25-fold, respectively, while P40, directed to the GPIIIa 260-302 sequence, did not show any antithrombotic activity. We conclude that all the mabs directed to the N-terminal domain of GPIIIa, which inhibit platelet aggregation in vitro and whose epitopes are very close to each other and exposed in resting platelets, have high antithrombotic activity in vivo, which varies depending on the actual location of the epitopes in the receptor topography. Among these antibodies, P37, the strongest receptor inhibitor in vivo and whose epitope is most probably the closest to the fibrinogen binding site(s), seems the best candidate for comparative studies in animal models with today's best GPIIb-IIIa inhibitors and for clinical trials in humans in order to arrest or prevent thrombosis, reocclusion and late restenosis.