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1.
J Toxicol Environ Health A ; 86(18): 678-695, 2023 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-37482814

RESUMO

Hymenaea genus has been used in folk medicine in Brazil, but few studies investigated its toxicity profile. Thus, the aim of this study was to determine toxicological parameters of Hymenaea courbaril stem bark hydroalcoholic extract by utilizing three cell lines including murine macrophages (RAW 264.7), mouse fibroblast cells (L929) and human lung fibroblast (MRC-5), as well as Salmonella/microsome assay, and in vivo Caenorhabditis elegans model. The predominant detected phytoconstituents in the extract were coumarins, flavonoids, phenolics, tannins and saponins and by HPLC analysis, astilbin (AST) was found to be the main component. The DPPH assay demonstrated that H. courbaril hydroalcoholic extract exhibited potent antioxidant activity, with an IC50 of 3.12 µg/ml. The extract at concentrations of 400 and 800 µg/ml decreased cell viability 48 hr after treatment in L929 and MRC-5 cell lines. In the Raw 264.7 strain, just the highest concentration (800 µg/ml) lowered cell viability within 48 hr following exposure. The concentration of 100 µg/ml did not markedly affect cell viability in the trypan blue assay. In the alkaline comet assay the extract was found to be non-genotoxic. In the Ames test, the extract exhibited low mutagenic potential without metabolic activation, since only the highest concentrations produced an effect. H. courbaril extract only affected the survival of C. elegans at concentrations of 800 and 1600 µl/ml. These findings demonstrate that H. courbaril extract appears to exert low toxicity as evidenced in vitro and mutagenicity assays; however, the biological relevance of the response of C. elegans survival to safety assessments needs further studies.


Assuntos
Caenorhabditis elegans , Hymenaea , Camundongos , Humanos , Animais , Extratos Vegetais/toxicidade , Casca de Planta , Linhagem Celular
2.
J Med Food ; 24(6): 626-634, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33337272

RESUMO

The Myrciaria dubia (Myrtaceae) fruit is traditionally used to treat malnutrition due to its high levels of vitamin C and phenolic compounds. Because of its composition, this plant is very promising in the research of novel natural treatment for pain disorders. This study analyzed the phytochemical profile of M. dubia juice and assessed its antinociceptive and antiedematogenic potential. The phytochemical profile was determined through high-performance liquid chromatography (HPLC), the oral antinociceptive effect of M. dubia 50% juice (Md50) was evaluated by formalin, hot plate and Complete Freund's Adjuvant tests and the antiedematogenic activity by paw edema. HPLC revealed the presence of ascorbic acid, rutin, and ellagic acid as major compounds. Md50 showed an antinociceptive effect in the acute and chronic phases of the formalin test. In the hot plate test, Md50 also induced an antinociceptive effect of 0.5 up to 6 h, showing antinociceptive and antiedematogenic potential without changing the spontaneous locomotion of animals. All protocols were submitted and approved by the Ethics Committee for use of Animals of the Lutheran University of Brazil (protocol No. 2013-30P).


Assuntos
Myrtaceae , Extratos Vegetais , Analgésicos , Animais , Frutas/química , Camundongos , Fenóis/análise
3.
J Toxicol Environ Health A ; 82(17): 956-968, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31570063

RESUMO

Myrciaria dubia is a native plant from the Amazon region which produces red-purplish fruit rich in antioxidant compounds such as ascorbic acid, carotenoids, and phenolic. M. dubia fruit is used to prepare juices considered to possess high nutritional content providing health benefits. The aim of this study was to examine the ability of M. dubia juice to protect DNA against genomic instability induced by sub-acute ethanol consumption attributed to oxidative stress. Mice were treated for 28 days with juice at 25% and 50% diluted in distilled water or with the diluted combination juice plus ethanol (5 g/kg). The genotoxic/antigenotoxic and mutagenic/antimutagenic effects were assessed using comet assay in blood, liver, and kidney and micronucleus (MN) test with bone marrow. In addition, the mutagenicity was also evaluated using Salmonella/microsome assay. Phytochemical compounds were determined using HPLC/PDA/MS/MS. The juice did not induce genotoxic effects in blood, kidney, and liver cells at both doses. In combination with ethanol, the juice reduced the alcohol-mediated DNA damage in all tissues analyzed. Further, the juice did not produce mutagenic effects and decreased mutagenicity induced by ethanol in the bone marrow. The anthocyanins were major compounds detected by HPLC/PDA/MS/MS, which modulated genotoxic and mutagenic effects initiated by ethanol and at least in part appeared responsible for the observed antigenotoxic and antimutagenic effects of M. dubia juice.


Assuntos
Antimutagênicos/química , Dano ao DNA/efeitos dos fármacos , Frutas/química , Mutagênicos/efeitos adversos , Myrtaceae/química , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Animais , Brasil , Masculino , Camundongos
4.
Radiol Bras ; 52(1): 7-11, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30804609

RESUMO

OBJECTIVE: To assess the percent agreement between diagnostic imaging modalities for the evaluation of lymphadenopathies in HIV-infected/AIDS patients. MATERIALS AND METHODS: This was an open, comparative, prospective study of diagnostic imaging methods for lymphadenopathy evaluation. We evaluated 30 patients (19 men and 11 women). All underwent ultrasound and computed tomography (CT). Twenty of the patients also underwent magnetic resonance imaging (MRI). We determined the percent agreement between two examiners using the various imaging methods to evaluate lymphadenopathies. RESULTS: CT had the highest percent agreement, at 93.3%, with a kappa coefficient of 0.85, corresponding to 28 of the 30 examinations. When we compared the percent agreement between the two examiners and between CT and ultrasound, examiner 1 had an observed rate of 80.0%, with a kappa of 0.49, corresponding to 24 of the 30 examinations, whereas examiner 2 had a rate of 70.0%, with a kappa of 0.31, corresponding to 21 of the 30 examinations. Between MRI and CT, the percent agreement for examiner 1 was 50.0%, with a kappa of -0.18, corresponding to 10 of the 20 examinations, whereas that for examiner 2 was 85.0%, with a kappa of 0.69, corresponding to 17 of the 20 examinations. For MRI and ultrasound, examiner 1 had a percent agreement of 70.0%, with a kappa of 0.20, corresponding to 14 of the 20 examinations, and examiner 2 had a percent agreement of 75.0%, with a kappa of 0.38, corresponding to 15 of the 20 examinations. CONCLUSION: This study indicates that intermethod agreement is highly dependent on the way in which the research is conducted, rather than on the level of experience of the examiner.


OBJETIVO: Avaliar a porcentagem de concordância entre métodos de diagnóstico por imagem na avaliação de linfonodomegalias em pacientes HIV(+)/AIDS. MATERIAIS E MÉTODOS: Foi realizado estudo aberto, comparativo e prospectivo dos métodos de diagnóstico por imagem na avaliação de linfonodomegalias. Foram avaliados 30 pacientes (19 homens e 11 mulheres). Todos foram submetidos a ultrassonografia e tomografia computadorizada (TC) e 20 também foram submetidos a ressonância magnética (RM). Foi determinado o grau de concordância entre dois examinadores usando-se métodos de diagnóstico por imagem. RESULTADOS: A TC obteve o maior grau de concordância, com taxa de 28/30 (93,3%) e coeficiente kappa de 0,85. Quando comparado o grau de concordância para linfonodomegalias entre dois examinadores e entre TC e ultrassonografia, o examinador 1 teve taxa de 24/30 (80,0%) e kappa de 0,49, e o examinador 2 teve taxa de 21/30 (70,0%) e kappa de 0,31. Entre RM e TC, o examinador 1 teve taxa de 10/20 (50,0%) e kappa de -0,18, e o examinador 2 teve taxa de 17/20 (85,0%) e kappa de 0,69. Entre RM e ultrassonografia, o examinador 1 teve taxa de 14/20 (70,0%) e kappa de 0,20, e o examinador 2 teve taxa de 15/20 (75,0%) e kappa de 0,38. CONCLUSÃO: Este estudo indica que a concordância entre métodos depende fortemente da forma como a pesquisa é conduzida e não da capacidade do examinador.

5.
Trop Anim Health Prod ; 47(8): 1531-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26245916

RESUMO

Eighty boars (19.3 ± 2.49 kg) were vaccinated twice (100 and 128 days of age) against gonadotropin releasing hormone (Vivax™ vaccine), for a randomised block design study aiming to evaluate five digestible lysine (DLys) level treatments, with three phase-feeding per treatments (9-8-7; 10-9-8; 11-10-9; 12-11-10 and 13-12-11 g/kg) during the growing-finishing phases (54-100, 100-128 and 128-155 days of age, respectively). Pigs were fed their respective diets ad libitum from 54 to 155 days and weighed at 100, 128 and 155 days. Pig loin (Longissimus dorsi) area, loin depth and backfat thickness were measured by ultrasound at 100 and 155 days. Hot carcass weight, meat quantity and meat yield were measured at slaughter. From 54 to 100 days (pre-immunocastration), DLys levels linearly improved pig feed conversion and loin area, the level of DLys for minimum feed conversion and maximum loin area was 13 g/kg. However, DLys levels had no effect on the performance of boars from 54 to 128 days (pre-immunocastration), nor on the performance and carcass parameters of immunocastrated male pigs between 54 and 155 days. A sequence of diets containing 9, 8 and 7 g/kg of DLys fed from 54 to 100, 100 to 128 and 128 to 155 days, respectively, meet the requirement of growing-finishing immunocastrated male pigs.


Assuntos
Suplementos Nutricionais , Lisina/química , Sus scrofa/crescimento & desenvolvimento , Vacinas/uso terapêutico , Ração Animal/análise , Animais , Composição Corporal , Peso Corporal , Castração , Dieta , Hormônio Liberador de Gonadotropina/química , Masculino , Carne , Músculo Esquelético/crescimento & desenvolvimento , Suínos , Fatores de Tempo , Vacinação
6.
Food Chem Toxicol ; 50(7): 2275-81, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22542553

RESUMO

Myrciaria dubia, a plant native to the Amazon region, stands out as a fruit rich in vitamin C and other metabolites with nutritional potential. We evaluated the antioxidant, genotoxic and antigenotoxic potential of M. dubia juice on blood cells of mice after acute, subacute and chronic treatments. Flavonoids and vitamin C present in the fruit of M. dubia were quantified. In vitro antioxidant activity was evaluated by DPPH assay. Blood samples were collected for analysis after treatment, and the alkaline comet assay was used to analyze the genotoxic and antigenotoxic activity (ex vivo analysis using H(2)O(2)). The amount of vitamin C per 100mL of M. dubia was 52.5mg. DPPH assay showed an antioxidant potential of the fruit. No M. dubia concentration tested exerted any genotoxic effect on mice blood cells. In the ex vivo test, the juice demonstrated antigenotoxic effect, and acute treatment produced the most significant results. After the treatments, there was no evidence of toxicity or death. In conclusion, our data show that M. dubia juice has antigenotoxic and antioxidant activities, though with no genotoxicity for blood cells. Nevertheless, more in-depth studies should be conducted to assess the safety of this fruit for human consumption.


Assuntos
Antimutagênicos/farmacologia , Células Sanguíneas/efeitos dos fármacos , Myrtaceae/química , Extratos Vegetais/farmacologia , Animais , Antimutagênicos/toxicidade , Ensaio Cometa , Feminino , Masculino , Camundongos , Mutagênicos/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Testes de Toxicidade Subaguda
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