SARS-CoV-2 variants induce distinct disease and impact in the bone marrow and thymus of mice.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved to variants associated with milder disease. We employed the k18-hACE2 mouse model to study how differences in the course of infection by SARS-CoV-2 variants alpha, delta, and omicron relate to tissue pathology and the immune response triggered. We documented a variant-specific pattern of infection severity, inducing discrete lung and blood immune responses and differentially impacting primary lymphoid organs. Infections with variants alpha and delta promoted bone marrow (BM) emergency myelopoiesis, with blood and lung neutrophilia. The defects in the BM hematopoietic compartment extended to the thymus, with the infection by the alpha variant provoking a marked thymic atrophy. Importantly, the changes in the immune responses correlated with the severity of infection. Our study provides a comprehensive platform to investigate the modulation of disease by SARS-CoV-2 variants and underscores the impact of this infection on the function of primary lymphoid organs.

Lipid and color stability of the meat and sausages of broiler fed with calcium anacardate.

BACKGROUND: Anacardic acid, a phenolic compound, represents 90% of cashew nut shell liquid, which is a byproduct from the industrial processing of cashew nuts. This study aimed to add calcium anacardate (CA) to broilers' diets as a source of anacardic acid, to evaluate its antioxidant effect in breast meat and in processed meat products (sausages). For this purpose, birds were fed according to the following treatments: diet without antioxidant and diets containing 2.5, 5.0, 7.5, or 10.0 g kg-1 CA. Chicken breast meat was stored frozen for 90 days. The thigh and drumsticks were used to produce chicken sausages that were kept in refrigerated conditions for 90 days. Lipid oxidation and color stability were assessed every 30 days. RESULTS: For breast meat, a 2.5 g kg-1 concentration of CA was insufficient to retard lipid oxidation, whereas 10.0 g kg-1 gave rise to a pro-oxidant effect and 5.0 g kg-1 slowed the oxidation up to 50 days. A level of 7.5 g kg-1 of CA was effective in retarding oxidation, favoring colour stability during the 90-days frozen storage. For sausages, 2.5 g kg-1 of calcium anacardate in broiler diets was sufficient to retard lipid oxidation. Calcium anacardate 7.5 g kg-1 provided greater redness in the sausages compared with the control and with the other treatments containing 5.0 and 10.0 g kg-1 . CONCLUSIONS: Calcium anacardate is a potential natural antioxidant for breast meat and sausages in storage when added to broilers' diets. © 2018 Society of Chemical Industry.

Spouted bed as an efficient processing for probiotic orange juice drying.

This study evaluated the influence of spouted bed drying temperature and maltodextrin dextrose equivalent on the probiotic microbial survival during drying and storage period and on physicochemical properties of fermented probiotic orange juice in powder. Probiotic orange juice was spouted bed dried at 60, 70, 80 and 90°C using maltodextrin with a different dextrose equivalent (10, 20, 30 and 39). After drying, the microbial was higher when lower drying temperatures were applied. During the storage, the highest drying temperatures (80 and 90°C) negatively affected the microorganism survival. On the other hand, at the lowest drying temperature (60°C), the product presented higher Aw, what negatively affected the microbial survival during storage. The temperature of 70°C was the best to preserve the microbial viability during storage. Physicochemical parameters were improved when temperature increased and dextrose equivalent decreased.

Emotional and motor symptoms in riverside dwellers exposed to mercury in the Amazon. / Manifestações emocionais e motoras de ribeirinhos expostos ao mercúrio na Amazônia.

INTRODUCTION:: The investigation of clinical and neurological impactations associated with exposure to mercury levels in exposed populations is necessary in the Amazon. OBJECTIVE:: To analyze emotional and motor symptoms of riverside dwellers exposed by diet in the municipalities of Itaituba and Acará, in Pará, Brazil. METHODS:: Hair samples were collected to assess the total mercury (HgT). Demographic data as well as emotional (depression, anxiety and insomnia) and motor (paresthesia, muscle weakness, loss of balance when walking, tremors, limb pain and dysarthria) symptomatology data were obtained. RESULTS:: Mean levels of HgT in Itaituba were significantly higher (p < 0.0001) than in Acará. Emotional symptoms were identified in 26 (26.5%) participants from Itaituba and in 24 (52.2%) from Acará. Specific motor complaints in Itaituba occurred in 63 (64.3%) volunteers; the most frequently mentioned afflictions were limb pain (36.7%), paresthesia (32.6%) and muscle weakness (27.5%). In Acará, 33 (71.7%) participants had motor symptoms, the majority of which complained of paresthesia (54.3%), limb pain (52.2%) and tremors (34.8%). Average HgT levels in Itaituba in those with emotional and motor symptoms were above the tolerable levels (6 µg/g) determined by the World Health Organization. CONCLUSION:: Results showed that mercury levels in emotional and motor symptoms in Itaituba are higher than in riverside dwellers in Acará. Further studies, including the application of specific qualitative and/or quantitative standard tests, as well as the investigation of other clinical signs are necessary.

Powder lemon juice containing oligosaccharides obtained by dextransucrase acceptor reaction synthesis and dehydrated in sprouted bed.

Oligosaccharides can be synthesized using the sugars present in the fruit juices through the dextransucrase acceptor reaction. In the present work, the effect of reducing sugar and sucrose concentration on oligosaccharide formation in lemon juice was evaluated through response surface methodology. The oligosaccharide formation in lemon juice was favored at high concentrations of sucrose (75 g/L) and reducing sugar (75 g/L). At this synthesis conditions, an oligosaccharide concentration of 94.81 g/L was obtained with a conversion of 63.21% of the initial sugars into the target product. Oligosaccharides with degree of polymerization up to 11 were obtained. The lemon juice was dehydrated in spouted bed using maltodextrin as drying adjuvant. The powder obtained at 60°C with 20 % maltodextrin presented low moisture (2.24 %), low water activity (Aw = 0.18) and the lowest reconstitution time (~46 s). The results showed that lemon juice is suitable for oligosaccharides enzyme synthesis and can be dehydrated in spouted bed.

The use of headspace solid-phase microextraction (HS-SPME) to assess the quality and stability of fruit products: an example using red mombin pulp (Spondias purpurea L.).

The present study aimed to evaluate the volatiles profile of red mombin (Spondias purpurea) pulp and its powder produced by spray-drying (SD) as an example to show utility of headspace solid-phase microextraction (HS-SPME) in the analysis of parameters such as the quality and stability of fruit products. Volatiles profiles of the pulp were identified by gas chromatography-mass spectrometry (GC-MS), quantified by gas chromatography-flame ionization detector (GC-FID) and compared to the profile of the powder stored at 0, 60 and 120 days in plastic (PP) or laminated packages (LP). The results showed that the technique was able to identify 36 compounds in the red mombin pulp, 17 out of which have been described for the first time in this fruit, showing that red mombin fresh pulp appears to be unique in terms of volatiles composition. However, only 24 compounds were detected in the powder. This decrease is highly correlated (r2 = 0.99), at least for the majority of compounds, to the degree of volatility of compounds. Furthermore, the powder stored in PP or LP showed no statistical differences in the amounts of its components for a period of 120 days of storage. Finally, this work shows how HS-SPME analysis can be a valuable tool to assess the quality and stability of fruit products.

Hygroscopic behavior and degree of caking of grugru palm (Acrocomia aculeata) powder.

This work aims to investigate the hygroscopic behavior of grugru palm powder through adsorption isotherms and its degree of caking. The powders of grugru palm (T1 - without maltodextrin, T2 - with 8 % of maltodextrin) were obtained by oven drying at 65 °C for 25 h. The experimental data was obtained through static gravimetric method at temperatures of 25, 30, 35 and 40 °C with different saturated salt solutions. The models of GAB, BET, Henderson, and Oswin were fitted to experimental data. The values of hygroscopicity were 6.39 and 5.17 % and degrees of caking were 3.11 and 0.03 % for T1 and T2, respectively. The adsorption isotherms from mathematical models can be classified as Type III. The GAB and Oswin models were the best representing the behavior of the powder isotherms, T1 and T2, respectively. The grugru palm powder proved to be non-hygroscopic and non-agglomerating. The T2 with 8 % of maltodextrin presented the lowest hygroscopicity.

Endurance training stimulates growth and survival pathways and the redox balance in rat pancreatic islets.

Endurance training has been shown to increase pancreatic ß-cell function and mass. However, whether exercise modulates ß-cell growth and survival pathways signaling is not completely understood. This study investigated the effects of exercise on growth and apoptotic markers levels in rat pancreatic islets. Male Wistar rats were randomly assigned to 8-wk endurance training or to a sedentary control group. After that, pancreatic islets were isolated; gene expression and the total content and phosphorylation of several proteins related to growth and apoptotic pathways as well as the main antioxidant enzymes were determined by real-time polymerase chain reaction and Western blot analysis, respectively. Reactive oxygen species (ROS) production was measured by fluorescence. Endurance training increased the time to reach fatigue by 50%. Endurance training resulted in increased protein phosphorylation content of AKT (75%), AKT substrate (AS160; 100%), mTOR (60%), p70s6k (90%), and ERK1/2 (50%), compared with islets from control group. Catalase protein content was 50% higher, whereas ROS production was 49 and 77% lower in islets from trained rats under basal and stimulating glucose conditions, respectively. Bcl-2 mRNA and protein levels increased by 46 and 100%, respectively. Bax and cleaved caspase-3 protein contents were reduced by 25 and 50% in islets from trained rats, respectively. In conclusion, these results demonstrate that endurance training favors the ß-cell growth and survival by activating AKT and ERK1/2 pathways, enhancing antioxidant capacity, and reducing ROS production and apoptotic proteins content.

Comportamento higroscópico de pós de manga das variedades coité e espada e avaliação das características físico-químicas / Hygroscopic behavior of mango powder of coité and espada cultivar and evaluation of physicochemical characteristics

A manga, embora muito apreciada pelos seus aspectos nutricionais e sensoriais, é altamente perecível e requer técnicas peculiares para sua conservação e comercialização. Nesse contexto, este trabalho teve por objetivos avaliar o comportamento higroscópico dos pós de manga das variedades Coité e Espada por meio das isotermas de adsorção e também analisar as características físico-químicas dessas variedades de manga nas formas in natura e em pó. Os resultados indicaram que os pós de manga não mostraram diferença significativa em relação às características físico-químicas, exceto para o valor de pH. Contrariamente, nas amostras in natura, apenas o pH não apresentou diferença significativa. Entre os modelos matemáticos utilizados para ajuste das isotérmicas de adsorção, o modelo de GAB foi o mais adequado para se ajustar aos dados experimentais, apresentando o teor de água da monocamada (gx100g-1 de matéria seca) de 0,09086 e 0,08857, com erros relativos médios de 6,76 e 2,86 por cento para Coité e Espada, respectivamente. O modelo de Oswin foi o segundo modelo matemático que apresentou valores muito próximos de encaixar o modelo de GAB.

The mango, is much appreciated by its nutritional and sensorial characteristics, but is highly perishable and requires specific techniques for its conservation and marketing. In this sense, this study aimed to evaluate the hygroscopic behavior of powdered mango varieties Coite and Espada cv. using adsorption isotherms and physicochemical characteristics of theses varieties of mango in natura and powder. The results showed that the mango powders didn't show significant difference in relation to physicochemical characteristics, except for the pH value. In contrary, in nature samples only the pH didn´t show significant difference. Among the mathematical models used to fit the adsorption isotherms, the GAB model was the more appropriate to fit the experimental data showing the water content of the monolayer of 0,09086 and 0,08857 (gx100g-1 dry matter) and relative average errors of 6,76 and 2.86 percent for Coité and Espada, respectively. The Oswin model was the second mathematical model that showed very close values to fit the GAB model.

Atividade antioxidante e correlações com componentes bioativos de produtos comerciais de cupuaçu / Antioxidant activity and correlations with bioactive components from commercial products of cupuaçu

O cupuaçu é considerado um importante fruto tipicamente amazônico e apresenta polpa ácida, agradável e de aroma característico. Esses atributos de qualidade o colocam no ranking das exportações de frutas. No Brasil, o cupuaçu é consumido principalmente na forma de polpa congelada. Os estudos com marcas comerciais de polpa de cupuaçu que correlacionaram a atividade antioxidante aos níveis de compostos bioativos mostraram que a capacidade de sequestro de espécies radicalares, pelo método do radical ABTS, apresentou correlação positiva com os compostos fenólicos e não com os carotenoides e a vitamina C. Porém, todas as marcas avaliadas apresentaram diferenças significativas quanto aos teores de vitamina C, carotenoides e capacidade antioxidante total equivalente ao trolox.

The cupuaçu is considered an important Amazonic fruit, which presents acidic pulp, pleasant and characteristic flavor. This quality attributes places the cupuaçu in the ranking of exporting fruits. In Brazil, the cupuaçu is mostly consumed as frozen pulps. Studies with cupuaçu pulp brands correlated antioxidant activity with the levels of bioactive compounds and showed that antioxidant activity carried out through the ABTS radical presented a positive correlation only with the phenolic compounds and not with carotenoids and vitamin C. However, all the evaluated brands showed significant differences in the levels of vitamin C, carotenoids and trolox total equivalent antioxidant capacity.

Formulation and physicochemical and sensorial evaluation of biscuit-type cookies supplemented with fruit powders.

Cashew apple and guava residues from fruit juice industry were prepared as dehydrated fruit powders and used at different levels of wheat flour substitution for cookies formulations. The effects of guava and cashew apple fruit powders supplementation on physicochemical and sensorial characteristics of the cookies were evaluated. The pH, fibre and protein content were significantly affected. Biscuits with 15 g and 20 g/100g cashew apple and guava fruit powders showed the highest scores for sensorial attributes, respectively. The supplementation seems to be suited for wheat flour substitution and it is possible to obtain cookies with value-added food ingredient within the standards.

[Correlation between antioxidant activity and bioactive compounds of açaí (Euterpe oleracea Mart) comercial pulps]. / Correlação entre atividade antioxidante e compostos bioativos de polpas comerciais de açaí (Euterpe oleracea Mart).

The purpose of this work was to analyze commercial açaí pulp and to correlate the contribution of vitamin C, total carotenoids and phenolic compounds with the antioxidant activity of there products besides the examination of the standard related to the quality of the obtained products. Analysis were made with regard to pH, acidity total, soluble solids, sugars, color, water activity, vitamin C, total anthocyanins, total carotenoids, antioxidant activity and phenolic compounds. All parameters analyzed showed significative difference among the marks not added with preservatives and sucrose. The açaí fruit can be considered a fair source of vitamin C and good source of natural antioxidants. In regard to the correlation with the antioxidant activity only the total anthocyanins and the total carotenoids presented positive and significative correlation.

Correlação entre atividade antioxidante e compostos bioativos de polpas comerciais de açaí (Euterpe oleracea Mart)

Este trabalho objetivou caracterizar polpas comerciais de açaí, além de correlacionar a contribuição da vitamina C, carotenóides totais e compostos fenólicos com a atividade antioxidante desses produtos, verificando ainda os parâmetros referentes à qualidade dos produtos obtidos. Foram realizadas análises de pH, acidez total titulável, sólidos solúveis totais, açúcares, cor, atividade de água, vitamina C, antocianinas totais e carotenóides totais, atividade antioxidante e compostos fenólicos. Conclui-se que todos os parâmetros apresentaram diferença significativa entre as marcas não adicionadas de conservante e sacarose. O açaí pode ser considerado uma importante fonte de vitamina C, bem como uma grande fonte de antioxidantes. Em relação à correlação com a atividade antioxidante, somente as antocianinas totais e os carotenóides totais apresentaram correlação positiva e significativa.

Correlation between antioxidant activity and bioactive compounds of açaí (Euterpe oleracea Mart) comercial pulps. The purpose of this work was to analyze commercial açaí pulp and to correlate the contribution of vitamin C, total carotenoids and phenolic compounds with the antioxidant activity of there products besides the examination of the standard related to the quality of the obtained products. Analysis were made with regard to pH, acidity total, soluble solids, sugars, color, water activity, vitamin C, total anthocyanins, total carotenoids, antioxidant activity and phenolic compounds. All parameters analyzed showed significative difference among the marks not added with preservatives and sucrose. The açaí fruit can be considered a fair source of vitamin C and good source of natural antioxidants. In regard to the correlation with the antioxidant activity only the total anthocyanins and the total carotenoids presented positive and significative correlation.

Caracterização química de águas de coco de três variedades / Characterization chemical of coconut water for three varieties

O presente trabalho teve como objetivo avaliar as características físicas e químicas do coco e das águas de coco de três variedades: Anão Verde, Híbrido e Anão Amarelo. Nas determinações: peso do fruto, comprimento longitudinal e transversal, volume da água de coco, rendimento da polpa, sólidos solúveis totais, acidez total titulável, pH e condutividade elétrica, apenas esta última apresentou diferença estatisticamente significante (p=0,05) entre as variedades estudadas. Na análise dos resultados, no que diz respeito às características físicas, a variedade Híbrido apresentou maior peso e volume de água, enquanto a Anão Verde revelou maior rendimento de polpa. Em relação aos açúcares redutores totais e sacarose, a variedade Híbrido apresentou maiores teores que Anão Amarelo e Anão Verde (p 0,05). Dentre os minerais (Na, K, Ca, P e Mg), apenas o sódio apresentou diferença significante (p 0,05) entre as variedades pesquisadas.

Estudo da estabilidade do abacaxi pérola minimamente processado e embalado a vácuo, nas condições operacionais de uma empresa supermercadista / Study of the stability of the pineapple minimally processed and packed the vacuum, in the operational conditions of a supermarket company

Este trabalho teve como objetivo avaliar a estabilidade do abacaxi pérola minimamente processado e embalado a vácuo, nas condições operacionais de uma empresa supermercadista. Os frutos passaram pelas etapas de lavagem, desinfecção (200 ppm de hipoclorito de sódio por 5 minutos) e armazenamento em câmara fria por 12 horas. Sob uma temperatura de 18°C, os frutos sofreram dois tipos de processamento após serem descascados, imersos em solução de 20 ppm de hipoclorito de sódio e serem drenados por 3 minutos: o primeiro, embalado inteiro a vácuo e o segundo, cortado em rodelas e embalado em bandejas de isopor envolvidas por filme de PVC. A intervalos de 2 dias, durante um período de 10 dias foram coletadas amostras e submetidas às análises físicas, físico-químicas, microbiológicas e teste de aceitação. Ao final do experimento, conclui-se que os abacaxis embalados a vácuo apresentaram melhor padrão de qualidade e maior vida de prateleira que os abacaxis embalados em bandejas.

Variação espacial e temporal da precipitação no Estado do Pará / Spatial and temporal variation of precipitation in the State of Pará

Estudos sobre a climatologia das precipitações no Estado do Pará são essenciais para o planejamento das atividades agrícolas. A variação da precipitação anual e sazonal no Estado do Pará foi analisada com base em séries históricas de 23 anos (1976-1998) de dados diários de chuva. A análise foi realizada para 31 localidades do Estado do Pará, sendo os resultados representados em mapas com a utilização de técnicas de sistemas de informações geográficas (SIG). A variabilidade da precipitação anual e sazonal foi caracterizada com base no coeficiente de variação e no índice de variabilidade interanual relativo. A variação desses coeficientes para a precipitação anual no Estado do Pará foi de 15 a 30 por cento. As características mensais da estação chuvosa, em termos de início, fim e duração, foram determinadas utilizando-se o critério proposto por KASSAM (1979). A variação entre as datas de plantio precoces e tardias corresponderam aos decêndios identificados pelos dias julianos 309319 e 353363, respectivamente.