Egg proteins as allergens and the effects of the food matrix and processing.

Hen eggs are an important and inexpensive source of high-quality proteins in the human diet. Egg, either as a whole or its constituents (egg yolk and white), is a key ingredient in many food products by virtue of its nutritional value and unique functional properties, such as emulsifying, foaming, and gelling. Nevertheless, egg is also known because of its allergenic potential and, in fact, it is the second most frequent source of allergic reactions, particularly in children. This review deals with the structural or functional properties of egg proteins that make them strong allergens. Their ability to sensitize and/or elicit allergic reactions is linked to their resistance to gastroduodenal digestion, which ultimately allows them to interact with the intestinal mucosa where absorption occurs. The factors that affect protein digestibility, whether increasing it, decreasing it, or inducing a different proteolysis pattern, and their influence on their capacity to induce or trigger an allergic reaction are discussed. Special attention is paid to the effect of the food matrix and the processing practices on the capacity of egg proteins to modulate the immune response.

In vivo methods for testing allergenicity show that high hydrostatic pressure hydrolysates of ß-lactoglobulin are immunologically inert.

The major milk allergen ß-lactoglobulin (ß-LG) exhibits an enhanced susceptibility to proteolysis under high hydrostatic pressure and this may be an efficient method to produce hypoallergenic hydrolysates. The aim of this work was to evaluate the in vivo allergenicity of 3 ß-LG hydrolysates produced under atmospheric pressure or high-pressure conditions. Hydrolysates were chosen based on previous experiments that showed that they provide a complete removal of intact ß-LG but differed in vitro IgE-binding properties that could be traced to the peptide pattern. The ability to trigger systemic anaphylaxis was assessed using C3H/HeJ mice orally sensitized to ß-LG. Outcome measures included symptom score, body temperature, serum mouse mast cell protease 1 (mMCP-1), and quantification of circulating basophils. Mast cell degranulation in vivo was assessed by passive cutaneous anaphylaxis. The 3 tested hydrolysates showed an abrogated allergenicity as revealed by the absence of anaphylactic symptoms and a decrease in body temperature. We demonstrated that the peptides present in the hydrolysates had lost their ability to cross-link 2 human IgE antibodies to induce mast cell degranulation, thus indicating that most of the peptides formed retain just one relevant IgE-binding epitope. The orally sensitized mouse model is a useful tool to address the in vivo allergenicity of novel milk formulas and demonstrates the safety of hydrolysates produced under high-pressure conditions.

Efficacy, safety and immunological actions of butanol-extracted Food Allergy Herbal Formula-2 on peanut anaphylaxis.

BACKGROUND: Therapies for peanut allergy (PNA) are urgently needed. Food Allergy Herbal Formula-2 (FAHF-2) has profound therapeutic effects in a murine PNA model and is safe for food-allergic adults in clinical trials. However, the large FAHF-2 pill-load is not conducive to clinical studies in children. Thus, refining FAHF-2 to decrease pill-load is essential for the inclusion of children in clinical trials and to facilitate studying FAHF-2 as a clinically useful botanical drug. OBJECTIVES: Testing long-term efficacy and safety of a butanol-purified extract of FAHF-2 (B-FAHF-2) in a murine model of PNA, and to explore its immunological mechanisms of action. METHODS: FAHF-2 was purified by butanol extraction. C3H/HeJ mice with established PNA received the first course of B-FAHF-2 at 6 mg, twice daily for 7 weeks (PNA/B-FAHF-2) or water (PNA/sham) and were then challenged immediately after completing the treatment and six more times every 1-2 months post-treatment up to week 50. Mice then received a second course of B-FAHF-2 treatment at week 52 and were challenged at week 65. In vivo and in vitro immunological effects on T, B and mast cells were also determined. RESULTS: Butanol purification reduced the volume of the effective dose ∼5-fold. All PNA/B-FAHF-2 mice were completely protected from PN anaphylaxis until the fifth challenge after the first course of treatment, as compared with PNA/sham mice. Partial protection persisted up to 50 weeks. A second treatment course restored complete protection. B-FAHF-2 significantly suppressed Th2 cytokine, IgE and histamine levels in vivo, and showed direct inhibition of Th2, IgE-producing B cells and mast cell activation in vitro. B-FAHF-2 had a high margin of safety. CONCLUSION AND CLINICAL RELEVANCE: B-FAHF-2 produced long-lasting protection against PN anaphylaxis for approximately half of the murine life span without side-effects. B-FAHF-2 exhibited direct effects on multiple food allergy effector cells.

Técnicas de diagnóstico genético en pediatría / Genetic diagnosis techniques in pediatrics

Los genes responsables de una importante proporción de enfermedades pediátricas o involucrados en las mismas, han sido clonados y caracterizados desde el punto de vista de su patología molecular. Las metodologías para la detección de mutaciones en ellos se van implementado cada vez más , y secuenciar un gen o determinar su dosificación forma parte de la rutina de una gran parte de los laboratorios de diagnóstico. Desde la biología molecular clásica de un gen-un experimento hasta la nueva tendencia de analizar en un experimento miles de genes por microarrays y, desde el tradicional estudio cromosómico hasta las técnicas de hibridación genómica comparada, no se debe olvidar el contexto de la patología genética dentro de la clínica del paciente. Este capítulo constituye una puesta al día resumida de las técnicas para estudiar las mutaciones y los cromosomas en la patología humana (AU)

The genes responsible of a high proportion of paediatric diseases have been cloned and characterized. Methologies to detect mutations in these genes are currently implemented in most of the molecular diagnosis laboratories. From a classical molecular biology experiment (one gene-one experiment= to the new micorarrays methodologies that analyse thousand of genes and form classical cytogenetics to the comparative genomic hybridization, the clinic context of the patient should not be forgotten. This chapter summarises most of the current methodologies to analyze genes and chromosomes involved in human pathologies (AU)

[Review of 22 patients with 22q11.2 deletion syndrome: phenotype spectrum]. / Revisión de 22 casos de deleción 22q11.2: espectro fenotípico.

INTRODUCTION: The 22q11.2 deletion syndrome is a contiguous gene deletion syndrome with an incidence rate of 1/4,000-6,000 live births. The most specific clinical features are: congenital conotruncal heart diseases, palate anomalies, hypocalcaemia, immunity and learning problems, and a characteristic facial phenotype. The objective of this work is to review the presenting phenotype and clinical features of children with 22q11.2 deletion syndrome as a guide for early diagnosis. PATIENTS AND METHODS: Retrospective study of 22 patients with 22q11.2 deletion syndrome diagnosed at our hospital in the time period 2004-2007. Variables analyzed: incidence, sex, age at diagnosis, presenting phenotype, clinical features, positive family history, mortality and natural history. RESULTS: From a total of 22 patients, 63 % were males, and the median age at diagnosis was of 4.5 years. Presenting pheno-type: congenital heart disease, milestones delay, velopharyngeal incompetence, hypocalcaemia, and mental retardation/psychiatric disturbances. CLINICAL FEATURES: congenital heart disease (84 %), velopharyngeal incompetence (47 %), milestones delay and learning disabilities (79 %). All of the deletions were de novo, except in one case where the deletion was present as mosaicism in the father. Three patients died, due to congenital heart disease. CONCLUSIONS: Clinical expression is widely variable, although a characteristic phenotype exists. Patients with heart disease are diagnosed earlier than other patients with unusual presenting phenotype such as congenital dysphagia. It is important to recognize less common phenotypes at early ages in order to provide multidisciplinary monitoring and accurate genetic counselling.

Revisión de 22 casos de deleción 22q11.2: espectro fenotípico / Review of 22 patients with 22q11.2 deletion syndrome: phenotype spectrum

Introducción: El síndrome de deleción 22q11.2 es un síndrome de genes contiguos con una incidencia de un caso por cada 4.000-6.000 recién nacidos. Posee una amplia variabilidad clínica y sus características clínicas más frecuentes son cardiopatía conotruncal, anomalías palatinas, hipocalcemia, problemas de inmunidad y de aprendizaje, y un fenotipo facial característico. El objetivo de este estudio es revisar las formas de presentación y las manifestaciones clínicas de los niños con deleción 22q11.2 como guía para su diagnóstico precoz. Pacientes y métodos: Estudio retrospectivo de 22 casos de deleción 22q11.2 diagnosticados en nuestro hospital entre los años 2004 y 2007, en que se analizan las siguientes variables: incidencia, sexo, edad en el momento del diagnóstico, forma de presentación, características clínicas, antecedentes familiares, mortalidad y evolución. Resultados: De los 22 pacientes, el 63 % fueron varones y la edad media en el momento de realizar el diagnóstico fue de 4,5 años. Las formas de presentación fueron cardiopatía, retraso psicomotor, insuficiencia velopalatina, hipocalcemia y retraso mental o alteraciones psiquiátricas. Las principales manifestaciones clínicas fueron cardiopatía (84 %), insuficiencia velopalatina (47 %), retraso psicomotor y problemas de aprendizaje (79 %). Todos los casos fueron deleciones de novo, salvo un caso en el que se identificó la deleción "en mosaico" en el padre. Fallecieron 3 pacientes a causa de cardiopatía. Conclusiones: La expresión clínica es muy variable, aunque existe un fenotipo característico. Los niños con cardiopatía conotruncal son diagnosticados más tempranamente, pero en otras formas de presentación, como la disfagia congénita, el diagnóstico se retrasa más. Es necesario tener en cuenta las formas de presentación menos habituales para identificar en edades tempranas a estos pacientes y proporcionarles una atención multidisciplinaria temprana y un asesoramiento genético familiar adecuado (AU)

Introduction: The 22q11.2 deletion syndrome is a contiguous gene deletion syndrome with an incidence rate of 1/4,000-6,000 live births. The most specific clinical features are: congenital conotruncal heart diseases, palate anomalies, hypocalcaemia, immunity and learning problems, and a characteristic facial phenotype. The objective of this work is to review the presenting phenotype and clinical features of children with 22q11.2 deletion syndrome as a guide for early diagnosis. Patients and methods: Retrospective study of 22 patients with 22q11.2 deletion syndrome diagnosed at our hospital in the time period 2004-2007. Variables analyzed: incidence, sex, age at diagnosis, presenting phenotype, clinical features, positive family history, mortality and natural history. Results: From a total of 22 patients, 63 % were males, and the median age at diagnosis was of 4.5 years. Presenting pheno-type: congenital heart disease, milestones delay, velopharyngeal incompetence, hypocalcaemia, and mental retardation/psychiatric disturbances. Clinical features: congenital heart disease (84 %), velopharyngeal incompetence (47 %), milestones delay and learning disabilities (79 %). All of the deletions were de novo, except in one case where the deletion was present as mosaicism in the father. Three patients died, due to congenital heart disease. Conclusions: Clinical expression is widely variable, although a characteristic phenotype exists. Patients with heart disease are diagnosed earlier than other patients with unusual presenting phenotype such as congenital dysphagia. It is important to recognize less common phenotypes at early ages in order to provide multidisciplinary monitoring and accurate genetic counseling (AU)

Synergistic effect between different milk-derived peptides and proteins.

Antimicrobial peptides derived from food proteins constitute a new field in the combined use of antimicrobial agents in food. The best examples of milk-derived peptides are those constituted by bovine lactoferricin [lactoferrin f(17-41)] (LFcin-B) and bovine alpha(s2)-casein f(183-207). The aim of this work was to study if the antimicrobial activity of a natural compound employed in food preservation, nisin, could be enhanced by combination with the aforementioned milk-derived peptides. Furthermore, the possibility of a synergistic effect between these peptides and bovine lactoferrin (LF) against Escherichia coli and Staphylococcus epidermidis was also studied. Finally, the most active combinations were assayed against the foodborne pathogens Listeria monocytogenes and Salmonella choleraesuis. Results showed a synergistic effect when LFcin-B was combined with bovine LF against E. coli. In the same way, the combination of LFcin-B with bovine LF was synergistic against Staph. epidermidis. Bovine LF and nisin increased their antimicrobial activity when they were assayed together with bovine alpha(s2)-casein f(183-207). It is important to note the synergistic effect among LFcin-B and bovine LF, because both compounds might be simultaneously in the suckling gastrointestinal tract and could, therefore, have a protective effect on it. The other synergistic effect high-lighted is that between alpha(s2)-casein f(183-207) and nisin against L. monocytogenes because of the ability of L. monocytogenes to develop resistance to nisin.

Duplication 19q13-qter and deletion 19p13-pter arising from an inversion (19)(p13.3q13.3) of maternal origin.

Pericentric inversion of chromosome 19 appears to be a rare abnormality with only a few families reported. As far as we are aware, none of them were ascertained because of a recombinant individual. We describe the first identified case due to an affected patient, with duplication deficiency for chromosome 19 arising from a maternal inversion confirmed by FISH and CGH. His features included prenatal growth retardation, microcephaly, dysmorphic facies, congenital heart defect, hypoplasia of corpus callosum and psychomotor delay. The identification of recombinant individuals contribute to calculate a precise risk for inv (19) carriers and to provide a more accurate genetic counselling.

Trisomía 22 en mosaico como causa de disgenesia ovárica asociada a un fenotipo Turner-Ullrich / Trisomy 22 mosaicism as a cause of ovarian dysgenesis associated with Turner-Ullrich phenotype

Se presenta un caso clínico de una paciente de 25 años con disgenesia ovárica debida a una trisomía 22 en mosaico. El cariotipo en sangre periférica resultó ser 46 XX. Las biopsias de ambas cintillas ováricas revelaron una trisomía 22 en mosaico, que se confirmó en fibroblastos cutáneos. Su hermana gemela es fenotípica y genotípicamente normal. La paciente fue diagnosticada en su infancia de enanismo tipo Russell-Silver. En la exploración clínica se apreció una hemiatrofia del hemicuerpo derecho, talla baja, cúbito valgo y amenorrea primaria, hallazgos clínicos compatibles con las características del síndrome de Ullrich-Turner. No se confirmó la presencia de disomía uniparental en sus progenitores como causa de la trisomía. Concluimos que la causa de la trisomía 22 en mosaico pudiera ser un error mitótico posfertilización

We report the case of a 25-year-old woman with ovarian dysgenesis due to trisomy 22 mosaicism. Karyotype in peripheral blood showed a normal 46 XX female. Biopsy of both ovarian streaks revealed trisomy 22 mosaicism in gonads. Cultured skin fibroblasts confirmed the alteration. The patient was born to a twin delivery. Although her sister was phenotypically normal, our patient was diagnosed with Russell-Silver dwarfism in childhood. Physical examination revealed significant right-side hemiatrophy, short stature, cubitus valgus, and absence of normal menarche. These findings are compatible with Ullrich-Turner syndrome. Uniparental disomy as a cause of the trisomy was investigated but was not confirmed in the parents' blood samples. We propose a postfertilization mitotic error as the cause of the trisomy 22 mosaicism