The role of probiotics and prebiotics in pediatric practice

OBJECTIVE: To review the effects of probiotics and prebiotics in clinical pediatric practice. SOURCES: MEDLINE was searched, especially for articles that addressed their practical application, in the form of reviews, clinical trials and meta-analyses. Articles that had already been analyzed by the authors were also included. SUMMARY OF THE FINDINGS: Scientific literature on probiotics and prebiotics has remarkably increased in the last 10 years. Their mechanisms of action have been experimentally investigated. Studies indicate that probiotics can act by competing with pathogens, modifying the intestinal environment by reduction in pH, as a result of fermentation products, interacting and modulating local and systemic inflammatory and immune response, among others. Clinical trials and meta-analyses show that probiotics seem to contribute towards the prevention of acute diarrhea and of antibiotic-associated diarrhea, in addition to shortening the duration of acute diarrhea. However, the data are inconsistent and there are no studies confirming their efficacy in terms of cost-benefit ratio. Preliminary studies show that probiotics in early life can reduce the occurrence of atopic dermatitis. The addition of prebiotics to infant formulas is associated with the change in the profile of the intestinal microbiota compared to infants fed milk formulas without prebiotics. CONCLUSIONS: Evidence indicates that new studies should be carried out about probiotics, prebiotics and symbiotics. The specific clinical effects that each probiotic or prebiotic may cause must be considered.OBJETIVO: Revisar os efeitos dos probióticos e prebióticos em situações clínicas da prática pediátrica. FONTES DOS DADOS: MEDLINE, preferencialmente os artigos que abordavam aspectos de aplicabilidade prática, na forma de revisões, ensaios clínicos e meta-análises. Artigos que já eram do conhecimento dos autores também foram utilizados. SÍNTESE DOS DADOS: A literatura científica sobre probióticos e prebióticos apresentou crescimento expressivo nos últimos 10 anos. Seus mecanismos de ação vêm sendo investigados experimentalmente. Os estudos indicam que os probióticos podem exercer seus efeitos competindo com patógenos, modificando o ambiente intestinal pela redução do pH, em conseqüência dos produtos da fermentação, interagindo e modulando a resposta inflamatória e imunológica local e sistêmica, entre outros. Ensaios clínicos e meta-análises mostram que os probióticos parecem contribuir para a prevenção da diarréia aguda e da diarréia associada ao uso de antibióticos, além de encurtar a duração da diarréia aguda. No entanto, existem dados contraditórios, além de não existirem ainda estudos confirmando sua efetividade do ponto de vista da relação custo-benefício. Estudos preliminares mostram que probióticos no início da vida podem reduzir a ocorrência de dermatite atópica. A adição de prebióticos em fórmulas para lactentes associa-se com mudança do perfil da microbiota intestinal em relação aos lactentes que recebem fórmula láctea sem prebióticos. CONCLUSÕES: As evidências indicam que novos estudos devem ser realizados sobre probióticos, prebióticos e simbióticos. Um aspecto que deve ser reforçado é a especificidade dos efeitos que cada probiótico ou prebiótico pode apresentar do ponto de vista clínico.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUniversidade de São Paulo Faculdade de Medicina Hospital das ClínicasUNIFESP, EPM, Depto. de PediatriaSciEL

On the Short Distance Part of the QCD Anomaly Contribution to the b --> s eta' Amplitude

In addressing the B --> eta' K puzzle, there has been a considerable hope in the literature to resolve it by the QCD anomaly contribution to the b --> s eta' amplitude. This contribution corresponds to the electroweak b --> s g* g* transition followed by the off-shell gluon fusion g* g* --> eta'. In the present paper we perform a critical reassessment of this issue. We show that for the hard virtual gluons in a loop there is a well defined short distance amplitude corresponding to a remnant of the QCD anomaly. However, we find that it cannot account for the measured amplitude. In addition, we point out that the reduction of the gluon fusion vertex for the off-shell gluons is compensated by an absence of the claimed suppression in the electroweak vertex, and that some nonperturbative contributions related to the QCD anomaly may still be viable in explaining the physical B --> eta' K amplitude.Comment: 11 pages, 4 figures, LaTeX + elsart.cls, to appear in Phys. Lett.

Axial Vector Couplings of the Nucleon in Chiral Quark Model Incorporating U(1)A U(1)_A Anomaly Effects

Renormalization of the axial vector currents due to Goldstone loops is studied in a simple extension of Manohar - Georgi chiral quark model which incorporates $U(1)_A$ anomaly effects. The polarized strage quark sea in the polarized nucleon results from different renormalization of the flavor singlet and octet currents and is in reasonable agreement with the experiment.Comment: 11 pages REVtex, 2 figures sent upon reques

Estudo de marcadores imunológicos para o diagnóstico e avaliação terapêutica da toxocaríase

In human toxocariasis, there are few approaches using immunological markers for diagnosis and therapeutic assessment. An immunoblot (IB) assay using excretory-secretory Toxocara canis antigen was standardized for monitoring IgG, IgE and IgA antibodies in 27 children with toxocariasis (23 visceral, three mixed visceral and ocular, and one ocular form) for 22-116 months after chemotherapy. IB sensitivity was 100% for IgG antibodies to bands of molecular weight 29-38, 48-54, 95-116, 121-162, >;205 kDa, 80.8% for IgE to 29-38, 48-54, 95-121, >; 205 kDa, and 65.4% for IgA to 29-38, 48-54, 81-93 kDa. Candidates for diagnostic markers should be IgG antibodies to bands of low molecular weight (29-38 and 48-54 kDa). One group of patients presented the same antibody reactivity to all bands throughout the follow-up study; in the other group, antibodies decayed partially or completely to some or all bands, but these changes were not correlated with time after chemotherapy. Candidates for monitoring patients after chemotherapy may be IgG antibodies to >; 205 kDa fractions, IgA to 29-38, 48-54, 81-93 kDa and IgE to 95-121 kDa. Further identification of antigen epitopes related to these markers will allow the development of sensitive and specific immunoassays for the diagnosis and therapeutic assessment of toxocariasis.Métodos imunológicos desempenham papel importante no diagnóstico da toxocaríase, entretanto há poucos estudos sobre marcadores diagnósticos e de acompanhamento terapêutico. Foi padronizado ensaio de immunoblot (IB) empregando antígeno de excreção-secreção de Toxocara canis para pesquisa de anticorpos IgG, IgE e IgA em 27 crianças com toxocaríase nas formas visceral (23), mista visceral e ocular (3) e ocular (1), por 22-116 meses após quimioterapia. Foram observados dois perfis de reatividade dos anticorpos: permanência contra todas as frações no decorrer do estudo; diminuição ou negativação contra algumas ou todas as frações, porém, essas mudanças não se correlacionaram com tempo de tratamento. A sensibilidade do IB foi 100,0% para anticorpos IgG específicos para frações de massa molecular de 29-38, 48-54, 95-116, 121-162, >; 205 kDa, 80,8% para IgE específicos para 29-38, 48-54, 95-121, >; 205 kDa e 65,4% para IgA específicos para 29-38, 48-54, 81-93 kDa. Anticorpos IgG específicos para frações de baixa MM (29-38 e 48-54 kDa) podem ser sugeridos como candidatos a marcadores diagnósticos. Por sua vez, anticorpos IgG para fração >; 205 kDa, IgA para 29-38, 48-54, 81-93 kDa e IgE para 95-121 kDa podem ser candidatos a marcadores terapêuticos. A identificação de epítopos antigênicos relacionados a estes marcadores poderá ser importante para o desenvolvimento de ensaios altamente sensíveis e específicos no diagnóstico e avaliação terapêutica da toxocaríase

DiGeorge Syndrome: a not so rare disease

INTRODUCTION: The DiGeorge Syndrome was first described in 1968 as a primary immunodeficiency resulting from the abnormal development of the third and fourth pharyngeal pouches during embryonic life. It is characterized by hypocalcemia due to hypoparathyroidism, heart defects, and thymic hypoplasia or aplasia. Its incidence is 1:3000 live births and, despite its high frequency, little is known about its natural history and progression. ←This is probably due to diagnostic difficulties and the great variety of names used to describe it, such as velocardiofacial, Shprintzen, DiGeorge, and CATCH 22 Syndromes, as well as conotruncal facial anomaly. All represent the same genetic condition, chromosome 22q11.2 deletion, which might have several clinical expressions. OBJECTIVES: To describe clinical and laboratorial data and phenotypic characteristics of patients with DiGeorge Syndrome. METHODS: Patients underwent standard clinical and epidemiological protocol and tests to detect heart diseases, facial abnormalities, dimorphisms, neurological or behavioral disorders, recurrent infections and other comorbidities. RESULTS: Of 14 patients (8m - 18y11m), only one did not have 22q11.2 deletion detected. The main findings were: conotruncal malformation (n = 12), facial abnormalities (n = 11), hypocalcemia (n = 5) and low lymphocyte count (n=2). CONCLUSION: The authors pointed out the necessity of DGS suspicion in all patient presenting with heart defects, facial abnormalities (associated or not with hypocalcemia), and immunological disorders because although frequency of DGS is high, few patients with a confirmed diagnosis are followed up

Frequency of seropositivity to Toxocara canis in children of different socioeconomic strata

Para estudar a freqüência da infecção pelo Toxocara canis em crianças de classes sociais diferentes de Brasília, Brasil, foram testados soros de 602 crianças de ambos os sexos, de 1 a 12 anos, distribuídas em dois grupos representativos de condições socioeconômicas distintas. As amostras do primeiro grupo foram obtidas em laboratório público que atende bairros pobres. As do segundo grupo foram colhidas em laboratório privado, que serve à classe média. Os anticorpos anti-Toxocara foram detectados pelo método ELISA, com antígenos de Toxocara canis, e absorção com antígenos do Ascaris suum. A prevalência de soropositividade foi de 21,8% (66/302) no primeiro grupo e de 3% (9/300) no segundo (p<0,0001). Não houve diferença quanto ao gênero ou idade das crianças. Os resultados sugerem significativa prevalência de toxocaríase na população infantil de Brasília, com predomínio nas classes sociais menos favorecidas economicamente. __________________________________________________________________________________________ ABSTRACTFrequency of seropositivity for Toxocara in children from different socioeconomic strata in the city of Brasilia (Brazil) was measured. Six hundred and two children of both sexes, aged one to 12 years were distributed in two socioeconomically distinct groups. The samples of sera of the first group were obtained from blood drawn for routine tests in the laboratory of a public hospital attending children from low-income families. Samples from the second group were obtained from private laboratories attending children from middle-class families. Antitoxocara antibodies were detected by ELISA, using Toxocara canis excretory-secretory antigens previously absorbed with Ascaris suum extract. The prevalence of seropositivity was 21.8% (66/302) in the first group and 3% (9/300) in the second (p< 0.0001). No differences in frequency according to age or sex could be detected. Our results suggest a high prevalence of childhood toxocariasis in Brasilia, with children from lower income brackets being the most affected

Hipogamaglobulinemia secundária ao uso de carbamazepina: apresentação de caso clínico e revisão da literatura

As alterações imunológicas relacionadas ao uso de anti-convulsivantes têm sido descrita há três décadas, envolvendo alterações celulares e humorais, sendo os mecanismos fisiopatológicos ainda não totalmente elucidados. Este relato descreve o caso de paciente portador de epilepsia parcial complexa com hipogamaglobulinemia durante o tratamento com carbamazepina, tendo apresentado melhora clínica e laboratorial importantes após substituição da droga pelo ácido valpróico. Os autores ressaltam a importância do acompanhamento clínico e laboratorial, incluindo avaliação dos níveis de imunoglobulinas e hemogramas seriados dos pacientes em uso contínuo de anticonvulsivantes.Immunologic disorders related to anticonvulsant therapy have been described in the last three decades, including cellular and humoral alterations that result in recurrent infections; however, the physiopathologic mechanisms are not completely understood. This report describes a patient with complex partial epilepsy and hypogammaglobulinemia while in treatment with carbamazepine, with significant improvement in clinical signs and laboratory tests after substitution to sodium valproate. The authors stress the importance of clinical and laboratory evaluation of patients in continuous anticonvulsant therapy, including immunoglobulins levels and peripheral blood evaluations

Immunogenicity and allergenicity of 2S, 7S and 11S soy protein fractions

Sabe-se que uma parte da população, principalmente crianças, são hipersensíveis à proteína de soja, embora não esteja completamente esclarecido qual a fração protéica mais alergênica. O objetivo do estudo foi comparar a imunogenicidade e alergenicidade das frações protéicas 2S (conglicinina), 7S (beta conglicinina) e 11S (glicinina) da soja, isoladas por cromatografia de afinidade. Essas frações protéicas foram usadas como antígenos para imunizar camundongos BALB/c e avaliar sua imunogenicidade pela produção de anticorpos IgM e IgG por ELISA. A alergenicidade dessas frações foi avaliada de acordo com os seguintes procedimentos: i) produção de anticorpos IgE contra as três frações protéicas por camundongos BALBc pelo teste de anafilaxia cutânea passiva (PCA) e ii) produção de anticorpos IgG1 contra a fração 7S em camundongos BALB/c por ELISA. As frações 7S e 11S induziram a formação de anticorpos IgM e IgG. O teste de PCA mostrou que somente a fração 7S foi alergênica pela produção de anticorpos IgE. A fração protéica 7S induziu a formação de anticorpos IgG1 em camundongos imunizados com essa fração. Nosso estudo mostra que a fração protéica 7S da soja é importante para desencadear reações alérgicas em camundongos e pode contribuir para esclarecer a alergenicidade dos produtos derivados da soja.It is known that in a part of the population, mainly among children, some are hypersensitive to soybean protein, although it is not yet completely elucidated which protein fraction is more immunogenic/allergenic. The objective of the study was to compare the immunogenicity and allergenicity of the soy protein fractions. The 2S (conglycinin), 7S (beta conglycinin) and 11S (glycinin) fractions were isolated from soy protein by affinity chromatography. These purified soy protein fractions were used as antigens for immunizing BALB/c mice to evaluate their immunogenicity by following the appearance of specific IgM and IgG antibodies in blood serum by ELISA. The allergenicity of these soy protein fractions was evaluated by the following approaches: i) the production of IgE antibodies against 2S, 7S and 11S soy protein fractions by BALBc mice in the anaphylactic cutaneous passive test (PCA), and ii) the production of IgG1 specific antibodies against the 7S fraction in BALB/c mice. The 7S and 11S fractions induced the formation of IgM and IgG antibodies. The PCA test showed that only the 7S fraction was allergenic leading to the production of IgE antibodies. Another evidence that reinforces the allergenicity of the 7S soy protein fraction is the presence of IgG1 specific antibodies reactive to this protein fraction in immunized mice. Our study shows that the 7S soy protein fraction is important to elicit allergic reactions in mice and may contribute to elucidate the allergenicity of soy-derived products

Semileptonic six fermion processes at future e+e−e^+ e^- colliders: signal and irreducible background for top and WWZ physics

We compute several total and differential cross sections relevant to top and WWZ physics at future $e^+e^-$ colliders taking into account the full set of Feynman diagrams for six fermion final states. We also include in our calculations initial state radiation and beamstrahlung effects, and the most important QCD corrections in an approximate (naive) form. We compare such a complete approach with "production x decay" approximation and we suggest that in many physical studies the former is needed.Comment: 28 pages including 8 figures (7 ps). Latex. Uses Axodraw. Minor changes and some typos correcte

Interleukin 10 (IL10) and transforming growth factor 1 (TGF1) gene polymorphisms in persistent IgE-mediated cow's milk allergy

OBJECTIVES: The aim of this cross-sectional study was to evaluate whether interleukin 10 (IL10) and transforming growth factor β1 (TGFβ1) gene polymorphisms were associated with persistent IgE-mediated cow's milk allergy in 50 Brazilian children. The diagnostic criteria were anaphylaxis triggered by cow's milk or a positive double-blind, placebo-controlled food challenge. Tolerance was defined as the absence of a clinical response to a double-blind, placebo-controlled food challenge or cow's milk exposure. METHOD: The genomic DNA of the 50 patients and 224 healthy controls (HCs) was used to investigate five IL10 gene polymorphisms (-3575A/T, -2849A/G, -2763A/C, -1082G/A, -592C/A) and one TGFβ1 polymorphism (-509C/T). RESULTS: Among the five IL10 polymorphisms analyzed, homozygosis for the G allele at the -1082 position was significantly higher in the patients compared with the healthy controls (p = 0.027) and in the persistent cow's milk allergy group compared with the healthy controls (p = 0.001). CONCLUSIONS: Homozygosis for the G allele at the IL10 -1082G/A polymorphism is associated with the persistent form of cow's milk allergy