O impacto da amamentação no desenvolvimento de habilidades da linguagem infantil: um estudo populacional

O adequado desenvolvimento da linguagem oral na infância é fundamental e um dos marcos mais importantes para que a criança desenvolva outras capacidades cognitivas e sócioemocionais. Recentemente, estudos de forte impacto a nível global sugeriram que a amamentação poderia influenciar o desenvolvimento cognitivo. Evidenciaram a sua importância enquanto atividade motora da linguagem, e o seu reflexo em aspetos cognitivos (O presente estudo visou contribuir nesse sentido, evidenciando um dos marcos cruciais do desenvolvimento infantil: a linguagem e que comportamentos neonatais ajudam a protegê-la. Teve por objetivo compreender o impacto do aleitamento materno no desenvolvimento de diferentes aspetos da linguagem infantil e verificar se existe relação entre o tempo ou exclusividade da amamentação e os resultados do protocolo de avaliação da linguagem. Na presente investigação define-se como população os estudantes de 24 a 36 meses (de idade, da rede pública de escolas de educação infantil da cidade de Canoas, Rio Grande do Sul, Brasil. 193 crianças passaram pelo processo completo de avaliação (questionário preenchido pelos pais ou responsáveis e avaliação presencial, gravada em vídeo, para análise através do protocolo de observação comportamental, PROC). Os resultados obtidos nas diferentes provas foram submetidos à análise estatística com descrição dos valores da média, mediana, percentis 25 e 75 e desvio padrão. Foi considerado significante o valor de p < 0,05. No presente estudo foi possível observar a ação do tempo e da exclusividade da amamentação no desenvolvimento de todas as capacidades da linguagem infantil avaliadas pelo PROC. Demonstra-se que não somente as capacidades verbais (que justificadamente poderiam melhorar os scores pela ação da amamentação na musculatura facial), mas também as de aquisição e desenvolvimento da linguagem (como a compreensão verbal, a manipulação do objeto, o desenvolvimento do simbolismo, a organização do brinquedo, e os aspetos do desenvolvimento cognitivo) sofreram um impacto positivo na correlação “quanto maior o período de aleitamento materno exclusivo, maior a pontuação."The adequate development of oral language in infancy and childhood is fundamental and one of the most important factors in the progression of other skills, as well as in the process of socialization. However, recent global studies strongly suggest that breastfeeding could influence cognitive development. These studies evidenced the importance of breastfeeding in the motor activity of language (and its reflection in cognitive aspects. This study aimed to contribute in this sense, highlighting one of the crucial milestones of child development: language, and which neonatal behaviors help protect it. Along these lines, this research sought to understand the impact of breastfeeding on the different aspects of child language development and to verify the existence of a connection between the time or exclusivity of breastfeeding and the specific results of language evaluation protocols. The subjects in this investigation were students between 24-36 months of age in preschools of the public school system in the city of Canoas, in the state of Rio Grande do Sul, Brazil. One hundred ninety-three children were evaluated using a questionnaire completed by parents or guardians, as well as in-person evaluation recorded by video for analysis using a protocol for observational behavior. The results obtained from the different tests were submitted for statistical analysis consisting of mean, median, 25th and 75th percentiles, and standard deviation. A value of p < 0.05 was considered significant. In this study, it was possible to observe the effects of the time of exclusive breastfeeding in the development of every capacity of child language learning evaluated by the PROC.* The research showed that not only verbal capacities (an improvement which could be justified by the effects of breastfeeding on the facial muscles), but also the acquisition and development of language (such as verbal comprehension, object manipulation, use of symbolism, organization of toys, and aspects of cognitive development) were impacted positively in the correlation “the longer the period of exclusive breastfeeding, the better the results.”Le développement adéquat du langage oral lors de l'enfance est fondamental et l'un des moments les plus marquants pour que l'enfant développe d'autres habilités et puisse socialiser. Cependant, des récentes études à fort impact à niveau global ont suggéré que l'allaitement maternel pourrait influencer le développement cognitif de l'enfant. Ils ont souligné son importance notamment quant à l'activité motrice de langage (et son reflet sur l'aspect cognitif. La présente étude a visé contribuer dans ce sens, soulignant l'un des moments cruciaux du développement enfantin : le langage et les comportements néonatals aident à la protéger. De cette manière, cette étude a eu pour objectif de comprendre l'impact de l'allaitement maternel sur le développement des différents aspects du langage de l'enfant et de vérifier s'il existe une relation entre le temps ou l'exclusivité de l'allaitement ainsi que les résultats spécifiques du protocole d'évaluation du langage. Lors de cette investigation, l'échantillon de population étudié est composé d'étudiants de 24 à 36 mois (non complétés) d'âge, dans des établissements publics dans les villes de Canoas, Rio Grande do Sul, Brésil. 193 enfants sont passés par le processus complet d'évaluation (questionnaire complété par les parents ou représentants légaux et une évaluation présidentielle enregistrée en vidéo pour analyse selon le protocole d'observation comportementale). Les résultats obtenus lors des différentes épreuves ont été soumis pour analyse statistique avec descriptions des valeurs de moyenne, médiane, pourcentage 25, 75 e déviation de la norme. La valeur de p<0,05 a été considéré important. Dans la présente étude, il a été possible d'observer l'action du temps d'exclusivité dans le développement de toutes les capacités de langage de l'enfant évaluées par le PROC. A été démontré que non seulement les capacités verbales (que notamment pourraient améliorer les résultats par l'action de l'allaitement maternel dans la musculature faciale), mais aussi de l'acquisition et développement du langage (comme la compréhension verbale, la manipulation de l'objet, le développement de la symbolisme, l'organisation du jouet, et les aspects de développement cognitif ont eu un impact positif dans la corrélation «plus grande la période de l'allaitement exclusif, plus grand sera le résultat »

Hematological Changes in Dogs with Visceral Leishmaniasis Are Associated with Increased IFN-γ and TNF Gene Expression Levels in the Bone Marrow

Visceral leishmaniasis is associated with a variety of hematological abnormalities. In this study, we correlated the hematological changes in the peripheral blood of dogs naturally infected with Leishmania infantum (L. infantum) with the distribution of cell lineages and cytokine gene expression patterns in the bone marrow. Samples from 63 naturally semidomiciled dogs living in an endemic area of visceral leishmaniasis were analyzed. L. infantum infection was detected in 50 dogs (79.3%). Among those, 18 (32%) had positive splenic cultures and showed more clinical signs. They also had lower red blood cell counts and leukocytosis with an increased number of neutrophils and monocytes in peripheral blood compared to dogs negative to this test. L. infantum DNA was detected in the bone marrow of 8/14 dogs with positive splenic culture. Dogs with L. infantum infection in the bone marrow presented with histiocytosis (p = 0.0046), fewer erythroid cell clusters (p = 0.0127) and increased gene expression levels of IFN-γ (p = 0.0015) and TNF (p = 0.0091). The data shown herein suggest that inflammatory and cytokine gene expression changes in bone marrow may contribute to the peripheral blood hematological changes observed in visceral leishmaniasis.V.A. was supported by a scholarship from CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), FIOCRUZ and Instituto de Salud Carlos III (ISC-III).S

Parasite load in the blood and skin of dogs naturally infected by Leishmania infantum is correlated with their capacity to infect sand fly vectors

AbstractThe sand fly Lutzomyia longipalpis is primarily responsible for the transmission of visceral leishmaniasis (VL) in the New World, and dogs are considered to be the main urban reservoir of this disease. In order to improve the efficacy of control measures, it is essential to assess the transmission capacity of Leishmania infantum to the sand fly vector by naturally infected dogs. The present study investigated the existence of correlations between canine clinical presentation and the intensity of parasite load in the blood, skin and spleen of naturally infected dogs. In addition, we also attempted to establish correlations between the intensity of parasite load in canine tissue and the parasite load detected in sandflies five days after feeding on naturally infected dogs. A total of 23 dogs were examined and classified according to clinical manifestation of canine VL. Blood samples, splenic aspirate and skin biopsies were collected and parasite DNA was quantified by qPCR. Canine capacity to infect Lu. longipalpis with parasites was evaluated by xenodiagnosis and parasite loads were measured five days after feeding. No significant differences were observed with respect to canine clinical manifestation and the parasite loads detected in the blood, skin and spleen samples obtained from naturally infected dogs. Regardless of clinical canine visceral leishmaniasis (CVL) presentation and the degree of parasite burden, almost half of the dogs successfully infected sandflies with parasites, albeit to a low number of sandflies with correspondingly low parasite loads. Parasite loads in both canine blood and skin were shown to be positively correlated with the canine infectiousness to the sand fly vector, and positive correlations were also observed with respect to these tissues and the sand fly infection rate, as well as the parasite load detected in sandflies following xenodiagnosis. In conclusion, this indicates that parasite loads in both blood and skin can function as potentially reliable markers of canine capacity to infect sand fly vector

A multicentric evaluation of the recombinant Leishmania infantum antigen-based immunochromatographic assay for the serodiagnosis of canine visceral leishmaniasis.

Background: Visceral leishmaniasis (VL) is a serious public health challenge in Brazil and dogs are considered to be the main urban reservoir of the causative agent. The culling of animals to control VL in some countries makes the accurate diagnosis of canine VL (CVL) essential. Recombinant antigens rLci1A and rLci2B were selected from a cDNA library of Leishmania infantum amastigotes due to their strong potential as candidates in diagnostic testing for CVL. The present multicentric study aimed to evaluate the sensitivity of a prototype test using these antigens (DPPrLci1A/rLci2B) against 154 sera obtained from symptomatic dogs within three endemic areas of VL in Brazil. The specificity was evaluated using 40 serum samples from negative dogs and dogs infected with other pathogens. Sensitivity and specificity rates of DPP rLci1A/rLci2B prototype were compared to rates from other diagnostic tests currently in use by the Brazilian Ministry of Health, including DPP?LVC, EIE?LVC. Findings: DPP rLci1A/rLci2B prototype offered similar performance to that offered by DPP?LVC rapid test, as follows: sensitivity of 87% (CI 81?91) and 88% (CI 82?93) and specificity of 100% (CI 91?100) and 97% (CI 87?100), respectively for DPP rLci1A/rLci2B and DPP?LVC. When results of these two tests were considered concomitantly, sensitivity increased to 93.5% (CI 89?96). Conclusions: The recombinant antigens rLci1A and rLci2B represent promising candidates for use in a multi-antigen rapid test for CVL. The inclusion of novel antigens to the DPP rLci1A/rLci2B prototype model could offer additionally enhanced sensitivity to detect animals infected by L. infantum

Performance of recombinant chimeric proteins in the serological diagnosis of Trypanosoma cruzi infection in dogs.

Background: Dogs are considered sentinels in areas of Trypanosoma cruzi transmission risk to humans. ELISA is generally the method of choice for diagnosing T. cruzi exposure in dogs, but its performance substantially depends on the antigenic matrix employed. In previous studies, our group has developed four chimeric antigens (IBMP-8.1, 8.2, 8.3, and 8.4) and evaluated their potential for diagnosing T. cruzi exposure in humans. For human sera, these chimeric antigens presented superior diagnostic performances as compared to commercial tests available in Brazil, Spain, and Argentina. Therefore, in this study we have evaluated the potential of these antigenic proteins for detection of anti-T. cruzi IgG antibodies in dog sera. Methodology/Principal findings: The IBMP-ELISA assays were optimized by checkerboard titration. Subsequently, the diagnostic potential was validated through analysis of ROC curves and the performance of the tests was determined using double entry tables. Cross-reactivity was also evaluated for babesiosis, ehrlichiosis, dirofilariosis, anaplasmosis, and visceral leishmaniasis. Best performance was shown by IBMP-8.3 and IBMP-8.4, although all four antigens demonstrated a high diagnostic performance with 46 positive and 149 negative samples tested. IBMP-8.3 demonstrated 100% sensitivity, followed by IBMP-8.4 (96.7?100%), IBMP-8.2 (73.3?87.5%), and IBMP-8.1 (50?100%). The highest specificities were achieved with IBMP-8.2 (100%) and IBMP-8.4 (100%), followed by IBMP-8.3 (96.7?97.5%) and IBMP 8.1 (89.1?100%). Conclusions/Significance: The use of chimeric antigenic matrices in immunoassays for anti-T. cruzi IgG antibody detection in sera of infected dogs was shown to be a promising tool for veterinary diagnosis and epidemiological studies. The chimeric antigens used in this work allowed also to overcome the common hurdles related to serodiagnosis of T. cruzi infection, especially regarding variation of efficiency parameters according to different strains and cross-reactivity with other infectious diseases

Immunization of Experimental Dogs With Salivary Proteins From Lutzomyia longipalpis, Using DNA and Recombinant Canarypox Virus Induces Immune Responses Consistent With Protection Against Leishmania infantum

Metacyclic Leishmania promastigotes are transmitted by sand flies that inject parasites and saliva into the host's skin. Previous studies have demonstrated that DNA plasmids encoding Lutzomyia longipalpis salivary proteins LJM17 and LJL143, when used to immunize dogs, resulted in a systemic and local Th1 cell-mediated immunity that interfered in parasite survival in vitro. Here we evaluated the ability of these same salivary antigens to induce anti-Leishmania immunity and to confer protection by immunizing dogs using a novel vaccination strategy more suitable for use in the field. The strategy consisted of a single dose of plasmid followed by two doses of recombinant Canarypoxvirus (rCanarypoxvirus) expressing L. longipalpis salivary proteins (LJM17 or LJL143). Thirty days after the final immunization, dogs were intradermally challenged with 107Leishmania infantum promastigotes in the presence of L. longipalpis saliva. We followed the experimentally infected dogs for 10 months to characterize clinical, parasitological, and immunological parameters. Upon vaccination, all immunized dogs presented strong and specific humoral responses with increased serum concentrations of IFN-γ, TNF, IL-7, and IL-15. The serum of dogs immunized with LJM17 also exhibited high levels of IL-2, IL-6, and IL-18. L. infantum infection was established in all experimental groups as evidenced by the presence of anti-Leishmania IgG, and by parasite detection in the spleen and skin. Dogs immunized with LJM17-based vaccines presented higher circulating levels of IFN-γ, IL-2, IL-6, IL-7, IL-15, IL-18, TNF, CXCL10, and GM-CSF post-infection when compared with controls. Results demonstrated that relevant Leishmania-specific immune responses were induced following vaccination of dogs with L. longipalpis salivary antigen LJM17 administered in a single priming dose of plasmid DNA, followed by two booster doses of recombinant Canarypox vector. Importantly, a significant increase in pro-inflammatory cytokines and chemokines known to be relevant for protection against leishmaniasis was evidenced after challenging LJM17-vaccinated dogs as compared to controls. Although similar results were observed following immunization with LJL143, the pro-inflammatory response observed after immunization was attenuated following infection. Collectively, these data suggest that the LJM17-based vaccine induced an immune profile consistent with the expected protective immunity against canine leishmaniosis. These results clearly support the need for further evaluation of the LJM17 antigen, using a heterologous prime-boost vaccination strategy against canine visceral leishmaniosis (CVL)