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1.
Braz J Biol ; 83: e274991, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909589

RESUMO

The objective of this study was to evaluate the water status, photosynthetic pigments, and photochemical efficiency of mini watermelon plants under salt stress and phosphate fertilization. The experiment was conducted in pots under greenhouse conditions in Pombal, PB, Brazil. The experimental design used was randomized blocks in a 5 × 4 factorial scheme, with five levels of electrical conductivity of irrigation water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four doses of phosphorus (60, 80, 100, and 120% of the recommendation), with three replicates. The relative water content in the tissues decreased with the increase in ECw levels in all phosphorus doses, with decreases of 7.05, 7.81 and 8.83% per unit increase in ECw, in plants fertilized with 80, 100 and 120% P2O5. On the other hand, ECw levels increased electrolyte leakage, regardless of phosphorus doses of the recommendation. The synthesis of photosynthetic pigments and the quantum efficiency of photosystem II were inhibited by increasing water salinity from 0.3 dS m-1 in plants grown under phosphorus doses above 60% of the recommendation. Water salinity from 0.3 dS m-1 reduced chlorophyll b contents, initial, maximum, and variable fluorescence of mini watermelon plants, with a decrease of 11.86, 4.51, 4.53, and 4.54% per unit increment of ECw, respectively.


Assuntos
Citrullus , Fosfatos , Fotossíntese , Águas Salinas , Fósforo
2.
Braz J Biol ; 83: e274595, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37792747

RESUMO

The objective of this study was to evaluate the salicylic acid applications in attenuating the harmful effects of saline nutrient solution on the physiology and growth of 'Gaúcho' melon cultivated in the NFT hydroponic system. The experiment was conducted in a greenhouse, in Pombal-PB, Brazil. The cultivation system used was the Nutrient Film Technique - NFT hydroponics. A completely randomized split-plot design was used, with the plot referring to four levels of salinity in the nutrient solution - ECns (2.1 control, 3.2, 4.3, and 5.4 dS m-1) and the sub-plot four concentrations of salicylic acid (SA) (0, 1.5, 3.0, and 4.5 mM), applied via foliar spray, with six replications. Nutrient solution of 4.3 and 5.4 dS m-1 electrical conductivity promotes higher maximum and variable fluorescence, respectively. The stomatal conductance, transpiration, stem diameter, main branch length, leaf dry mass, and stem dry mass of 'Gaúcho' melon plants decrease with the increase in salinity of the nutrient solution. Salicylic acid increases the initial fluorescence and the main branch length of 'Gaúcho' melon plants in hydroponic cultivation. Salicylic acid at a concentration of 1.5 to 4.5 mM did not attenuate the effects of salt stress on the internal CO2 concentration, CO2 assimilation rate, and root dry mass of 'Gaúcho' melon plants.


Assuntos
Dióxido de Carbono , Cucurbitaceae , Hidroponia , Ácido Salicílico/farmacologia , Fluorescência , Estresse Salino , Clorofila
3.
Nutr Res ; 104: 29-35, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35588611

RESUMO

Cardiovascular diseases (CVDs) represent the leading cause of death in individuals worldwide. Gut microbiota-derived metabolite trimethylamine N-oxide (TMAO) can be metabolized from phosphatidylcholine, choline, and l-carnitine and may play an important role in CVD etiology. Thus, this systematic review aimed to evaluate the effect of probiotics to mitigate TMAO concentrations by gut microbiota modulation. A systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis protocol from databases: PubMed, Web of Sciences, CENTRAL, and Scopus. Controlled intervention studies published until January 3, 2022, with a population at cardiovascular risk were included. The risk of bias was assessed by RoB 2.0 and SYRCLE's for humans and animals' studies, respectively. The search in the database returned 5389 studies, of which 8 matched all criteria to final qualitative analysis. Four studies were controlled trials with humans (total population = 115) and 4 were animal model studies. The body of evidence on the use of probiotics to reduce TMAO concentrations shows that only a few strains have this beneficial effect. This review can conclude that Lactobacillus rhamnosus GG were the most efficient strains in reducing the plasma TMAO level in both humans and animals. In addition, it is worth mentioning the promising character of Lactobacillus plantarum ZDY04, Lactobacillus amylovorus LAM 1345, Lactiplantibacillus plantarum LP1145, and Enterobacter aerogenes ZDY01 for having had the same effect in animals.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Probióticos , Animais , Doenças Cardiovasculares/etiologia , Colina/metabolismo , Humanos , Metilaminas
4.
Zygote ; 30(3): 419-422, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34689852

RESUMO

The aim of this study was to evaluate the effect of 1 µmol/l zearalenone (ZEN) and 1 µmol/l matairesinol (MAT), alone or in combination, on the morphology of in vitro-cultured ovarian preantral follicles. Ovaries from four adult sheep were collected at a local slaughterhouse and fragmented, and the ovarian pieces were submitted to in vitro culture for 3 days in the presence or absence of the test compounds. The morphology of primordial and primary follicles was impaired by ZEN. The plant lignan MAT alone did not maintain the morphology of the ovarian follicles; its combination with ZEN counteracted the negative effects observed when follicles were cultured in the presence of the mycotoxin alone. However, MAT was not able to promote the in vitro development of the ovarian follicles.


Assuntos
Lignanas , Zearalenona , Animais , Feminino , Furanos , Lignanas/farmacologia , Folículo Ovariano , Ovário , Ovinos , Zearalenona/toxicidade
5.
Theriogenology ; 174: 124-130, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34428678

RESUMO

The aim of this study was to evaluate the effect of 1 µmol/L zearalenone (ZEN) and 1 µmol/L enterolactone (ENL), alone or in combination, on the survival and morphology of in vitro cultured ovarian preantral follicles. Ovaries from 10 sheep were collected at a local abattoir and fragmented, and the ovarian pieces were submitted to in vitro culture for 3 days in the presence or absence of the test compounds. The morphology of primordial and primary follicles was impaired by ZEN, whereas that of cultured secondary follicles was improved by ENL. However, the combination of ENL with ZEN impaired the quality of primary and secondary follicles. Both ZEN and ENL induced apoptosis, but only ZEN was responsible for oocyte autophagy. None of these xenoestrogens affected endoplasmic reticulum stress as observed by the unaltered expression of ERP29. Differently from ZEN, ENL increased the expression of the efflux transporter ABCG2. In conclusion, although ENL can counteract the negative effects of ZEN on primordial and primary follicles, this positive effect is not similar to that observed in ovarian tissue cultures in the presence of ENL alone.


Assuntos
Zearalenona , 4-Butirolactona/análogos & derivados , Animais , Feminino , Lignanas , Oócitos , Folículo Ovariano , Ovário , Ovinos , Zearalenona/toxicidade
6.
J Mech Behav Biomed Mater ; 117: 104378, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33610021

RESUMO

Polymeric scaffolds provide several advantages when compared with other bone replacement and regenerating techniques. Namely, when compared with the current gold standard, bone autografts, there is no shortage of supply nor donor site morbidity. Contrarily to metallic implants, their mechanical properties are similar to those of cortical bone and they are biodegradable, therefore stress shielding is not expected to occur, and they will be gradually replaced by new bone tissue. Yet, there are still several challenges to overcome. After implantation scaffolds are subjected to dynamic loads, thus understanding polymeric scaffolds' fatigue behavior plays a major role on the design of better products. In this work PLA scaffolds were manufactured using 3D printing with optimized parameters. A total of six configurations were tested under static and dynamic load conditions. Static compression testing and numerical simulation showed good correlation. Numerical simulation provided a viable resource for scaffold design and innovation. Four different low-cycle fatigue loads were applied, during 3600 cycles with a frequency of 0.25 Hz. While under dynamic conditions, with a maximum stress of 24 MPa and R = 0.1, the apparent compressive modulus reached 973 MPa, due to pore collapse. Even after 3600 cycles no significant fatigue damage mechanisms were found on low porosity scaffolds, rendering them useful for trabecular bone replacement under dynamic conditions.


Assuntos
Osso Esponjoso , Tecidos Suporte , Força Compressiva , Teste de Materiais , Porosidade , Impressão Tridimensional , Engenharia Tecidual
7.
Mater Sci Eng C Mater Biol Appl ; 118: 111528, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255081

RESUMO

Bone transplant is still the gold standard approach when dealing with orthopedic trauma or disease. When this solution is not possible, scaffolding is a possibility provided by bone tissue engineering. To support the regeneration process, damaged bone tissue is removed and replaced by porous scaffold structures. In recent years, additive manufacturing has shown huge potential to produce scaffold structures with the required performance. In the current work, PLA scaffolds with different designs were 3D printed, using optimal manufacturing parameters. Scaffolds with three different porosity values were obtained by changing the filament offset from 571 to 1333 µm. A total of twelve designs were tested under monotonic and dynamic compression conditions. Numerical analysis showed good correlation with experimental results, allowing for a better assessment of scaffold mechanical behavior. Stress relaxation was measured on four different strain levels, assessing scaffold's behavior after implantation and consequent static response over time. Overall, orthogonal design provided better performance, due to improved material deposition. With lower porosity scaffolds equilibrium stress reached 24 MPa after 300 s relaxation time under 4% deformation, and the obtained equilibrium modulus was 428 MPa. Overall, attained results show that 3D printing with PLA can be applied in the manufacture of scaffolds for trabecular bone replacement.


Assuntos
Osso Esponjoso , Tecidos Suporte , Poliésteres , Porosidade , Impressão Tridimensional , Engenharia Tecidual
8.
Braz J Med Biol Res ; 53(6): e9031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401929

RESUMO

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1ß immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Assuntos
Apolipoproteína A-I/sangue , Dieta/efeitos adversos , Inflamação/metabolismo , Desnutrição/metabolismo , Animais , Apolipoproteína A-I/metabolismo , Brasil , Doença Crônica , Humanos , Inflamação/sangue , Inflamação/patologia , Fígado/metabolismo , Masculino , Desnutrição/sangue , Desnutrição/patologia , Camundongos , Camundongos Endogâmicos C57BL
9.
Trop Biomed ; 37(3): 763-777, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33612789

RESUMO

The aim of this study was to evaluate the prevalence of enteroparasitic infections in students and their hormonal and immunological repercussions on physical development. Students of basic education of both sexes were evaluated. Parasitological stool tests were performed using the Hoffman and Kato-Katz methods. The students were divided into two groups: a control group (negative parasitological examination, N=25) and an infected group (positive parasitological test, N=25). Anthropometric variables (height, weight, and BMI), concentrations of hormones (melatonin and cortisol), cytokine/chemokine levels (IL-1ß, IL-6, IL-8, IL-10, IL-12, IL-17 and TNF-α) and physical performance (aerobic capacity, upper- and lower-limb muscle strength and abdominal performance) were evaluated. The prevalence of parasitic infection among the students was 7.98%. No anthropometric differences were observed among the groups. IL-2 and TNF-α levels were higher and IL-8 levels were lower in serum from students who were positive for parasitic infection. Serum from students who were positive for parasitic infection showed higher levels of melatonin than that from parasitenegative students. No differences were observed in cortisol levels. Students who were positive for parasitic infection presented greater lower-limb strength and lower abdominal performance than parasite-negative students. In the parasitic infection group, IL-12 was positively correlated with melatonin. In the parasitic infection group, IL-8 showed a positive correlation with aerobic capacity, while IL-17 and TNF-α showed a positive correlation with abdominal performance. These data suggest that parasitic infections determine the profile of inflammatory cytokines and that melatonin may be involved in the control of this process to minimize tissue damage. Additionally, students' difficulty in practising physical exercises can be an indication of enteroparasitic infection.


Assuntos
Enteropatias Parasitárias/fisiopatologia , Aptidão Física , Adolescente , Brasil/epidemiologia , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Hidrocortisona/sangue , Enteropatias Parasitárias/epidemiologia , Masculino , Melatonina/sangue , Prevalência , Estudantes
10.
Tropical Biomedicine ; : 763-777, 2020.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-825630

RESUMO

@#The aim of this study was to evaluate the prevalence of enteroparasitic infections in students and their hormonal and immunological repercussions on physical development. Students of basic education of both sexes were evaluated. Parasitological stool tests were performed using the Hoffman and Kato-Katz methods. The students were divided into two groups: a control group (negative parasitological examination, N=25) and an infected group (positive parasitological test, N=25). Anthropometric variables (height, weight, and BMI), concentrations of hormones (melatonin and cortisol), cytokine/chemokine levels (IL-1β, IL-6, IL-8, IL-10, IL-12, IL-17 and TNF-α) and physical performance (aerobic capacity, upper- and lower-limb muscle strength and abdominal performance) were evaluated. The prevalence of parasitic infection among the students was 7.98%. No anthropometric differences were observed among the groups. IL-2 and TNF-α levels were higher and IL-8 levels were lower in serum from students who were positive for parasitic infection. Serum from students who were positive for parasitic infection showed higher levels of melatonin than that from parasitenegative students. No differences were observed in cortisol levels. Students who were positive for parasitic infection presented greater lower-limb strength and lower abdominal performance than parasite-negative students. In the parasitic infection group, IL-12 was positively correlated with melatonin. In the parasitic infection group, IL-8 showed a positive correlation with aerobic capacity, while IL-17 and TNF-α showed a positive correlation with abdominal performance. These data suggest that parasitic infections determine the profile of inflammatory cytokines and that melatonin may be involved in the control of this process to minimize tissue damage. Additionally, students’ difficulty in practising physical exercises can be an indication of enteroparasitic infection.

11.
Braz. j. med. biol. res ; 53(6): e9031, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132523

RESUMO

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1β immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.


Assuntos
Humanos , Animais , Masculino , Coelhos , Ratos , Apolipoproteína A-I/sangue , Desnutrição/metabolismo , Dieta/efeitos adversos , Inflamação/metabolismo , Brasil , Doença Crônica , Apolipoproteína A-I/metabolismo , Desnutrição/patologia , Desnutrição/sangue , Inflamação/patologia , Inflamação/sangue , Fígado/metabolismo , Camundongos Endogâmicos C57BL
12.
Int Immunopharmacol ; 73: 293-303, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128529

RESUMO

Egg yolk constitutes a relevant alternative source of antibodies. It presents some advantages over mammalian serum immunoglobulins regarding productivity, animal welfare and specificity. The main immunoglobulin present in avian blood (IgY) is transmitted to their offspring and accumulates in egg yolks, which enables the non-invasive harvesting of high amounts of antibodies. Moreover, due to structural differences and phylogenetic distance, IgY is more suitable for diagnostic purposes than mammalian antibodies, since it does not react with certain components of the human immune system and displays greater avidity for mammalian conserved proteins. IgY has been extensively used in health researches, as both therapeutic and diagnostic tool. This article aims to review its applications in both human and veterinary health.


Assuntos
Gema de Ovo/imunologia , Imunoglobulinas/uso terapêutico , Animais , Bioterrorismo , Conservação de Alimentos , Humanos , Imunoglobulinas/química , Imunoglobulinas/imunologia , Infecções/diagnóstico , Infecções/imunologia , Neoplasias/diagnóstico , Neoplasias/imunologia
13.
Transbound Emerg Dis ; 65(1): e40-e47, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28649801

RESUMO

Vaccinia virus (VACV) is the agent of bovine vaccinia (BV), an emerging zoonosis that causes exanthematic lesions on the teats of dairy cows and on the hands of milkers. The virus has been detected in the milk of naturally infected cows. The objective of this study was to investigate and quantify VACV DNA as well as the presence of infectious virus particles in samples of cheese curd, cheese whey and pasteurized milk produced using milk from cows experimentally inoculated with VACV-GP2, a Brazilian isolate of VACV (VACV-BR). VACV DNA was detected in samples of cheese and pasteurized milk at different time points, even after the resolution of the typical lesions caused by VACV, which occurred after 22 days post-infection (dpi), on average. Moreover, it was possible to detect infectious viral particles in cheese samples on alternate days until 27 dpi. The presence of both VACV DNA and infectious viral particles in cheese samples throughout the clinical course of BV and even after the disappearance of the typical clinical signs of disease draws attention to the risk associated with consumption of the cheese. Furthermore, VACV-contaminated milk and cheese may represent an occupational risk to cheesemakers who often manipulate milk and cheese curd without wearing gloves.


Assuntos
Doenças dos Bovinos/virologia , Laticínios/virologia , Doenças Transmitidas por Alimentos/virologia , Leite/virologia , Vírus Vaccinia/isolamento & purificação , Vaccinia/veterinária , Animais , Bovinos , Queijo/virologia , DNA Viral/análise , Feminino , Reação em Cadeia da Polimerase/veterinária , Saúde Pública , Vaccinia/virologia , Vírus Vaccinia/genética , Zoonoses
14.
Environ Toxicol Pharmacol ; 56: 198-203, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28961514

RESUMO

Carnauba wax is extracted from the leaves of the Copernicia prunífera and contains approximately 80% of esters in its composition. The purpose of the present study was evaluate the hypolipidemic effect of p-methoxycinnamic diesters (PCO-C) extracted from Copernicia prunífera in a model of acute and chronic dyslipidemia in mice. The levels of total cholesterol and triglycerides were significantly reduced plasma levels in PCO-C at the dose of 100mg/kg in a model of acute and chronic dyslipidemia. Histological studies showed that PCO-C has no hepatotoxic effect and reduces hepatic steatosis in animals that consumed hyperlipidemic ration. Thus, it was concluded that PCO-C isolated from Copernicia Prunifera was effective in reducing total cholesterol and triglyceride levels in both dyslipidemia induction models. The finding indicates that PCO-C might be beneficial in treatment of hyperlipidemia and atherosclerosis.


Assuntos
Arecaceae/química , Dislipidemias/tratamento farmacológico , Ésteres/administração & dosagem , Extratos Vegetais/administração & dosagem , Animais , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Dislipidemias/induzido quimicamente , Ésteres/química , Ésteres/farmacologia , Masculino , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Triglicerídeos/sangue , Ceras/química , Ceras/farmacologia
15.
Braz J Med Biol Res ; 50(10): e6361, 2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28876366

RESUMO

Diabetes mellitus is one of the most common chronic degenerative diseases, and it is estimated to increase worldwide to around 415 million and to impact 642 million in 2040. Research shows that some plants are sources of bioactive compounds against diabetes. Thus, the objective of this work was to evaluate the oral toxicity and the hypoglycemic effect of the aqueous extract of the leaves of Cnidoscolus quercifolius Pohl. Diabetes was induced in Swiss mice with streptozotocin and the mice were treated with an aqueous extract of C. quercifolius leaves for a period of 30 days. Phytochemical analysis showed that the extract was rich in flavonoids, catechins and triterpenoid, which did not show any mortality and behavioral alterations in mice treated with 200, 1000, and 2000 mg/kg body weight of the extract for 14 days. Histopathological analysis of organs (kidney, pancreas, liver) from mice treated with the 2000 mg/kg extract revealed no architectural change. In the present study, we found a 29% reduction in glucose levels in animals receiving 200 mg/kg body weight. These results are very promising because they showed that C. quercifolius had a hypoglycemic effect and did not present oral toxicity, thus being a new source of compounds for the control of diabetes.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Euphorbiaceae/química , Hipoglicemiantes/uso terapêutico , Extratos Vegetais/uso terapêutico , Animais , Feminino , Hipoglicemiantes/toxicidade , Rim/efeitos dos fármacos , Dose Letal Mediana , Fígado/efeitos dos fármacos , Masculino , Camundongos , Pâncreas/efeitos dos fármacos , Extratos Vegetais/toxicidade , Estreptozocina , Testes de Toxicidade
16.
Chemosphere ; 188: 650-658, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28923728

RESUMO

Brazil nut tree (Bertholletia excelsa) is native of the Amazon rainforest. Brazil nuts are consumed worldwide and are known as the richest food source of selenium (Se). Yet, the reasoning for such Se contents is not well stablished. We evaluated the variation in Se concentration of Brazil nuts from Brazilian Amazon basin, as well as soil properties, including total Se concentration, of the soils sampled directly underneath the trees crown, aiming to investigate which soil properties influence Se accumulation in the nuts. The median Se concentration in Brazil nuts varied from 2.07 mg kg-1 (in Mato Grosso state) to 68.15 mg kg-1 (in Amazonas state). Therefore, depending on its origin, a single Brazil nut could provide from 11% (in the Mato Grosso state) up to 288% (in the Amazonas state) of the daily Se requirement for an adult man (70 µg). The total Se concentration in the soil also varied considerably, ranging from <65.76 to 625.91 µg kg-1, with highest Se concentrations being observed in soil samples from the state of Amazonas. Se accumulation in Brazil nuts generally increased in soils with higher total Se content, but decreased under acidic conditions in the soil. This indicates that, besides total soil Se concentration, soil acidity plays a major role in Se uptake by Brazil nut trees, possibly due to the importance of this soil property to Se retention in the soil.


Assuntos
Bertholletia , Nozes/química , Selênio/análise , Solo/química , Adulto , Brasil , Humanos , Política Nutricional
18.
Sci Rep ; 7: 40585, 2017 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-28079159

RESUMO

Silencing of SOCS1 protein with shRNAi lentivirus (shR-SOCS1) led to partial reversion of the tumorigenic phenotype of B16F10-Nex2 melanoma cells. SOCS1 silencing inhibited cell migration and invasion as well as in vitro growth by cell cycle arrest at S phase with increased cell size and nuclei. Down-regulation of SOCS1 decreased the expression of epidermal growth factor receptor, Ins-Rα, and fibroblast growth factor receptors. The present work aimed at analyzing the SOCS1 cell signaling and expression of proteins relevant to tumor development. An RNA microarray analysis of B16F10-Nex2 melanoma cells with SOCS1 silenced by shRNAi-SOCS1 was undertaken in comparison with cells transduced with the empty vector. Among 609 differentially expressed genes, c-Kit, Met and EphA3 cytokine/tyrosine-kinase (TK) receptors were down regulated. A significant decrease in the expression of TK receptors, the phosphorylation of mediators of ERK1/2 and p38 pathways and STAT3 (S727) were observed. Subcutaneous immunization with shR-SOCS1-transduced viable tumor cells rendered protection against melanoma in a syngeneic model, with decreased expression of PD-L1 and of matrix metallo-proteinases (MMPs) and CD-10 in those cells. The present work shows the role of SOCS1 in murine melanoma development and the potential of SOCS1-silenced tumor cells in raising an effective anti-melanoma immune response.


Assuntos
Antígeno B7-H1/metabolismo , Progressão da Doença , Transição Epitelial-Mesenquimal , Imunidade , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/metabolismo , Linfócitos T CD8-Positivos/imunologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Melanoma Experimental/genética , Antígenos Específicos de Melanoma/metabolismo , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Substâncias Protetoras/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Transcrição AP-2/metabolismo , Transcrição Gênica , Fator de Crescimento Transformador beta/metabolismo , Microambiente Tumoral , Regulação para Cima/genética
19.
Mater Sci Eng C Mater Biol Appl ; 71: 412-424, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27987725

RESUMO

The nanotoxicity of Cd-containing quantum dots (QDs) for biomedical applications is very controversial and not completely understood. In this study, we evaluated the cytotoxicity of surface-biofunctionalized CdS QDs with chitosan directly synthesized via aqueous route at room temperature. These core-shell CdS-chitosan nanoconjugates showed different degrees of cytotoxic responses using MTT cell proliferation assay toward three human cell cultures, human osteosarcoma cell line (SAOS), non-Hodgkin's B cell lymphoma (Toledo), and human embryonic kidney cell line (HEK293T), under three exposure times (1, 3, and 5days) and three colloidal concentrations (10nM, 50nM, and 100nM). The results clearly demonstrated that the CdS QDs, regardless to the fact that they were coated with a biocompatible aminopolysaccharide shell, induced a severe dose- and time-dependent inhibition of cell viability. In addition, the HEK293T and SAOS cell lines showed much more sensitive response compared to Toledo, which indicated that the cytotoxicity was also cell-type dependent. The exceptional resistance of Toledo cells to toxic effects of CdS nanoconjugates even at severe test conditions was assigned to specific role of B-lineage cells of the immune defense system. Remarkably, no conclusive evidence of toxicity of CdS nanoconjugates was observed in vivo using intravenous injections of CdS nanoconjugates in BALB/c mouse animal models for 30days, but localized fluorescence was detected in ex-vivo liver tissue samples. Therefore, these results prove that there is no guarantee of "risk-free" use of CdS nanoconjugates for in vivo applications, even when functionalized with biopolymer ligands, as they can pose an excessive threat due to unpredicted and uncorrelated responses under in vitro and in vivo biological assays with highly toxic cadmium ions.


Assuntos
Compostos de Cádmio , Quitosana , Pontos Quânticos/química , Sulfetos , Animais , Compostos de Cádmio/efeitos adversos , Compostos de Cádmio/química , Compostos de Cádmio/farmacologia , Linhagem Celular Tumoral , Quitosana/efeitos adversos , Quitosana/química , Quitosana/farmacologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Sulfetos/efeitos adversos , Sulfetos/química , Sulfetos/farmacologia
20.
Braz J Med Biol Res ; 49(10): e5340, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27737316

RESUMO

Undernutrition represents a major public health challenge for middle- and low-income countries. This study aimed to evaluate whether a multideficient Northeast Brazil regional basic diet (RBD) induces acute morphological and functional changes in the ileum of mice. Swiss mice (∼25 g) were allocated into two groups: i) control mice were fed a standard diet and II) undernourished mice were fed the RBD. After 7 days, mice were killed and the ileum collected for evaluation of electrophysiological parameters (Ussing chambers), transcription (RT-qPCR) and protein expression (western blotting) of intestinal transporters and tight junctions. Body weight gain was significantly decreased in the undernourished group, which also showed decreased crypt depth but no alterations in villus height. Electrophysiology measurements showed a reduced basal short circuit current (Isc) in the undernourished group, with no differences in transepithelial resistance. Specific substrate-evoked Isc related to affinity and efficacy (glutamine and alanyl-glutamine) were not different between groups, except for the maximum Isc (efficacy) induced by glucose. Transcription of Sglt1 and Pept1 was significantly higher in the undernourished group, while SN-2 transcription was decreased. No changes were found in transcription of CAT-1 and CFTR, while claudin-2 and occludin transcriptions were significantly increased in the undernourished group. Despite mRNA changes, SGLT-1, PEPT-1, claudin-2 and occludin protein expression showed no difference between groups. These results demonstrate early effects of the RBD on mice, which include reduced body weight and crypt depth in the absence of significant alterations to villus morphology, intestinal transporters and tight junction expression.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Crescimento/fisiologia , Íleo/anatomia & histologia , Íleo/metabolismo , Desnutrição/metabolismo , Desnutrição/fisiopatologia , Doença Aguda , Animais , Peso Corporal , Modelos Animais de Doenças , Ingestão de Energia/fisiologia , Immunoblotting , Absorção Intestinal/fisiologia , Transporte de Íons/fisiologia , Masculino , Desnutrição/complicações , Proteínas de Membrana Transportadoras/análise , Camundongos , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas de Junções Íntimas/análise , Proteínas de Junções Íntimas/metabolismo , Fatores de Tempo
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