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1.
An Acad Bras Cienc ; 96(3): e20221041, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39194050

RESUMEN

Cerrado is the second largest biome in Brazil, and it is responsible for providing us several ecosystem services, including the functions of storing Carbon and biodiversity conservation. In this study, we developed a modeling approach to predict the Aboveground biomass (AGB) in Cerrado vegetation using Artificial Neural Networks (ANNs), vegetation indices retrieved from RapidEye satellite imagery, and field data acquired within the Federal District territory, Brazil. Correlation testing was performed to identify potential vegetation index candidates to be used as input in the AGB modeling. Several ANNs were trained to predict the AGB in the study area using vegetation indices and field data. The optimum ANN was selected according to criteria of mean error of the estimate, correlation coefficient, and graphical analysis. The best performing ANN showed a predictive power of 90% and RMSE less than 17%. The validation tests showed no significant difference between the observed and ANN-predicted values. We estimated an average AGB of 16.55± 8.6 Mg.ha-1 in shrublands in the study area. Our study results indicate that vegetation indices and ANNs combined could accurately estimate the AGB in the Cerrado vegetation in the study area, showing to be a promising methodological approach to be broadly applied throughout the Cerrado biome.


Asunto(s)
Biomasa , Redes Neurales de la Computación , Tecnología de Sensores Remotos , Brasil , Ecosistema , Monitoreo del Ambiente/métodos
2.
Braz J Med Biol Res ; 55: e12314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36477952

RESUMEN

Seminal studies stated that bean proteins are efficient neuronal tracers with affinity for brain tissue. A low molecular weight peptide fraction (<3kDa) from Phaseolus vulgaris (PV3) was previously reported to be antioxidant, non-cytotoxic, and capable of reducing reactive oxygen species and increasing nitric oxide in cells. We evaluated the effects of PV3 (5, 50, 100, 500, and 5000 µg/kg) on behavior and the molecular routes potentially involved. Acute and chronic PV3 treatments were performed before testing Wistar rats: i) in the elevated plus-maze (EPM) to assess the anxiolytic-like effect; ii) in the open field (OF) to evaluate locomotion and exploration; and iii) for depression-like behavior in forced swimming (FS). Catecholaminergic involvement was tested using the tyrosine hydroxylases (TH) enzyme inhibitor, α-methyl-DL-tyrosine (AMPT). Brain areas of chronically treated groups were dissected to assess: i) lipid peroxidation (LPO); ii) carbonylated proteins (CP); iii) superoxide dismutase (SOD) and catalase (CAT) enzymatic activities. Neuronal nitric oxide synthases (nNOS) and argininosuccinate synthase (ASS) protein expression was evaluated by western blotting. Acute treatment with PV3 increased the frequency and time spent in the EPM open arms, suggesting anxiolysis. PV3 increased crossing episodes in the OF. These PV3 effects on anxiety and locomotion were absent in the chronically treated group. Acute and chronic PV3 treatments reduced the immobility time in the FS test, suggesting an antidepressant effect. TH inhibition by AMPT reverted acute PV3 effects. PV3 decreased LPO and CP levels and SOD and CAT activities, whereas nNOS and ASS were reduced in few brain areas. In conclusion, PV3 displayed central antioxidant actions that are concomitant to catecholaminergic-dependent anxiolytic and antidepressant effects.


Asunto(s)
Phaseolus , Animales , Ratas , Peso Molecular , Óxido Nítrico , Ratas Wistar , Péptidos , Tirosina
3.
Braz. j. med. biol. res ; 55: e12314, 2022. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1403915

RESUMEN

Seminal studies stated that bean proteins are efficient neuronal tracers with affinity for brain tissue. A low molecular weight peptide fraction (<3kDa) from Phaseolus vulgaris (PV3) was previously reported to be antioxidant, non-cytotoxic, and capable of reducing reactive oxygen species and increasing nitric oxide in cells. We evaluated the effects of PV3 (5, 50, 100, 500, and 5000 µg/kg) on behavior and the molecular routes potentially involved. Acute and chronic PV3 treatments were performed before testing Wistar rats: i) in the elevated plus-maze (EPM) to assess the anxiolytic-like effect; ii) in the open field (OF) to evaluate locomotion and exploration; and iii) for depression-like behavior in forced swimming (FS). Catecholaminergic involvement was tested using the tyrosine hydroxylases (TH) enzyme inhibitor, α-methyl-DL-tyrosine (AMPT). Brain areas of chronically treated groups were dissected to assess: i) lipid peroxidation (LPO); ii) carbonylated proteins (CP); iii) superoxide dismutase (SOD) and catalase (CAT) enzymatic activities. Neuronal nitric oxide synthases (nNOS) and argininosuccinate synthase (ASS) protein expression was evaluated by western blotting. Acute treatment with PV3 increased the frequency and time spent in the EPM open arms, suggesting anxiolysis. PV3 increased crossing episodes in the OF. These PV3 effects on anxiety and locomotion were absent in the chronically treated group. Acute and chronic PV3 treatments reduced the immobility time in the FS test, suggesting an antidepressant effect. TH inhibition by AMPT reverted acute PV3 effects. PV3 decreased LPO and CP levels and SOD and CAT activities, whereas nNOS and ASS were reduced in few brain areas. In conclusion, PV3 displayed central antioxidant actions that are concomitant to catecholaminergic-dependent anxiolytic and antidepressant effects.

4.
Food Chem ; 339: 127818, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-32854038

RESUMEN

Native extracts from orange peels were obtained by a conventional method using acetone and, an alternative method using ionic liquid (1-butyl-3-methylimidazolium chloride ([C4mim]Cl)). The bioaccessibilities and cellular uptakes of carotenoids, esters and chlorophylls were evaluated, since the influence of esterification on bioaccessibility and bioavailability is not well established. For this, the extracts were emulsified, submitted to in vitro simulated digestion model according to the INFOGEST protocol, followed by uptake by Caco-2 cells. Compounds were separated, identified and quantified by HPLC-PDA-MS/MS. After digestion, 22.0% and 26.2% of the total carotenoids and 45.9% and 68.7% of the chlorophylls were bioaccessible from the acetone and [C4mim]Cl extracts, respectively. The bioaccessibilities of xanthophylls and carotenes were significantly higher than those of the mono- and diesters. The uptake by Caco-2 cells varied from 130.2 to 131.9 ng/mg cell protein for total carotenoids and from 243.8 to 234.2 ng/mg cell protein for chlorophylls in the acetone and [C4mim]Cl extracts, respectively. In general, xanthophylls and esters were better absorbed than carotenes.


Asunto(s)
Carotenoides/farmacocinética , Fraccionamiento Químico/métodos , Clorofila/farmacocinética , Citrus sinensis/química , Disponibilidad Biológica , Células CACO-2 , Carotenoides/análisis , Carotenoides/aislamiento & purificación , Clorofila/análisis , Clorofila/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Digestión , Ésteres/farmacocinética , Frutas/química , Humanos , Líquidos Iónicos/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacocinética , Espectrometría de Masas en Tándem , Xantófilas/análisis , Xantófilas/aislamiento & purificación , Xantófilas/farmacocinética
5.
Antioxidants (Basel) ; 8(12)2019 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-31816926

RESUMEN

Orange peel is a by-product produced in large amounts that acts as a source of natural pigments such as carotenoids. Xanthophylls, the main carotenoid class found in citrus fruit, can be present in its free form or esterified with fatty acids, forming esters. This esterification modifies the compound's chemical properties, affecting their bioavailability in the human body, and making it important to characterize the native carotenoid composition of food matrices. We aimed to evaluate the non-saponified carotenoid extracts of orange peel (cv. Pera) obtained using alternative green approaches: extraction with ionic liquid (IL), analyzed by high performance liquid chromatography coupled to a diode array detector with atmospheric pressure chemical ionization and mass spectrometry HPLC-DAD-APCI-MS, and supercritical fluid extraction (SFE), followed by supercritical fluid chromatography with atmospheric pressure chemical ionization and triple quadrupole mass spectrometry detection (SFC-APCI/QqQ/MS) in an online system. Both alternative green methods were successfully applied, allowing the total identification of five free carotenoids, one apocarotenoid, seven monoesters, and 11 diesters in the extract obtained with IL and analyzed by HPLC-DAD-APCI-MS, and nine free carotenoids, six carotenoids esters, 19 apocarotenoids, and eight apo-esters with the SFE-SFC-APCI/QqQ/MS approach, including several free apocarotenoids and apocarotenoid esters identified for the first time in oranges, and particularly in the Pera variety, which could be used as a fruit authenticity parameter.

6.
Food Res Int ; 126: 108653, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31732025

RESUMEN

The aim of this study was to develop a new method for carotenoid extraction from orange peel, using ionic liquid (IL) to replace conventional organic solvents, assisted by ultrasound. Four different IL were tested: 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), 1-n-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]), 1-n-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]), and 1-hexyl-3-methylimidazolium chloride ([HMIM][Cl]). Response surface methodology was applied in order to optimize the carotenoid extraction conditions, and Amberlite XAD-7HP resin was used to separate the carotenoids from the IL, allowing their recovery. Determination of carotenoids was carried out by high-performance liquid chromatography coupled to photodiode array and mass spectrometry detectors (HPLC-DAD-MSn). Thermal stability at different temperatures (60 °C and 90 °C) and peroxyl radical scavenging activity of the carotenoid extracts obtained with acetone and IL were evaluated. [BMIM][Cl] was the most effective IL, leading to a total carotenoid content of 32.08 ±â€¯2.05 µg/g, while 7.88 ±â€¯0.59 µg/g of dry matter was obtained by acetone extraction. IL and carotenoid recoveries using XAD-7HP resin were in the range of 59.5-63.8% and 52.2-58.7%, respectively. A carotenoid extract was successfully obtained with IL, finally isolated just by using ethanol, besides being more stable and presenting higher antioxidant activity than that obtained with acetone.


Asunto(s)
Carotenoides/aislamiento & purificación , Citrus sinensis/química , Frutas/química , Líquidos Iónicos , Acetona , Antioxidantes/química , Carotenoides/química , Estabilidad de Medicamentos , Depuradores de Radicales Libres/química , Calor , Imidazoles , Reproducibilidad de los Resultados , Ondas Ultrasónicas
7.
J Periodontal Res ; 51(3): 332-41, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26248485

RESUMEN

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the effects of administration of avocado/soybean unsaponifiable (ASU), a drug that is commonly used in the treatment of rheumatoid arthritis, on ligature-induced bone loss and bone repair after ligature removal in rats. MATERIAL AND METHODS: Eighty-four rats were randomly assigned to four groups of equal size and received a daily gavage of either sterile saline [control (CTR)] or ASU (0.6 mg/kg), starting 7 d before (ASU/-7), on the day of (ASU/0) or 7 d after (ASU/+7) periodontitis induction. Periodontitis was induced by placing silk ligatures into the gingival sulcus of the second maxillary molars for 7 d; after 7 d, the ligatures were removed. Seven rats from each group were sacrificed, 7, 15 or 30 d after ligature removal. Bone resorption was evaluated by histomorphometry and micro-computed tomography (micro-CT). Immunohistochemistry was used to evaluate the expression of TRAP, RANKL and alkaline phosphatase (ALP), and quantitative PCR (qPCR) was used to evaluate the levels of interleukin-1beta (Il1ß), tumor necrosis factor alpha (Tnfα), interleukin-6 (Il-6), Rankl and Alp. Statistical analysis was performed using the Shapiro-Wilk test, ANOVA and Tukey's test for normal data, and using the Kruskall-Wallis and Dunnet's tests for non-normal data (p < 0.05). RESULTS: Histomorphometry and micro-CT analysis showed greater bone resorption in the CTR group than in the ASU/0 (15 d) and ASU/+7 (7 and 15 d) groups. The CTR group also presented with a higher expression of TRAP (15 and 30 d) and RANKL (7 and 15 d) compared with ASU/0 and ASU/+7 groups. Similarly, qPCR analysis showed higher levels of Rankl and Il1ß mRNAs, and lower levels of Alp mRNA, in the CTR group compared with all other groups (for all periods). CONCLUSION: ASU exhibited a positive effect on bone repair following ligature-induced periodontitis in rats.


Asunto(s)
Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/patología , Glycine max/química , Persea/química , Extractos Vegetales/farmacología , Fosfatasa Alcalina/análisis , Animales , Artritis Reumatoide/tratamiento farmacológico , Expresión Génica , Encía/patología , Inmunohistoquímica , Interleucina-1beta/análisis , Interleucina-6/análisis , Ligadura , Masculino , Maxilar , Diente Molar , Periodontitis/patología , Extractos Vegetales/administración & dosificación , Reacción en Cadena de la Polimerasa , Ligando RANK/análisis , Distribución Aleatoria , Ratas , Seda , Fosfatasa Ácida Tartratorresistente/análisis , Factores de Tiempo , Factor de Necrosis Tumoral alfa/análisis , Microtomografía por Rayos X/métodos
8.
Pregnancy Hypertens ; 2(3): 268-9, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26105372

RESUMEN

INTRODUCTION: The ABO-system of antigens and the Rh-system (D-antigen) is genetically determined and remains the most important blood group systems clinically. Several studies have examined the association between ABO and Rhesus blood group systems and pre-eclampsia. At present there is no consensus to define this association, especially not in a Brazilian population. OBJECTIVES: The purpose of the present study was to evaluate the association between pre-eclampsia versus ABO and Rhesus blood group systems in pregnant women hospitalized in a University Hospital in Porto Alegre, Brazil -Hospital São Lucas (HSL). METHODS: Pre-eclampsia/eclampsia (PE/E) was diagnosed by the National High Blood Pressure Education Program Working Group Report on High Blood Pressure in Pregnancy guidelines. This study consisted of 14,894 pregnant women admitted to the Maternity Department between 2005 and 2010. The patients were reviewed retrospectively for inclusion. Complications in pregnancy not related to pre-eclampsia/eclampsia (PE/E) and those with uncompleted data were excluded. Medical records of 410 women were used to diagnose PE/E. The control group consisted of 8781 women. Each group was subdivided according to their blood groups. RESULTS: In comparison to the PE/E women and controls, no specific relation in blood groups was observed. With respect to ABO and Rh groups, no differences between PE/E and controls were observed (P=0.479 and P=0.169 respectively). When analyzed with both Rh and ABO Pearson Chi-Square also showed no differences (P=0.569). CONCLUSION: This study aimed to demonstrate some association between blood groups and PE/E using a large sample from the south of Brazil, a population not investigated before. In our study, no specific differences were observed between PE/E and controls in the distribution of the blood groups. In conclusion, the results of this study suggest no association between ABO and Rhesus blood group systems and PE/E in our population. FUNDING: CAPES Foundation-Ministry of Education of Brazil.

9.
Ultrason Sonochem ; 17(1): 34-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19632139

RESUMEN

An ultrasound-assisted preparation of a series of novel 3,5-diaryl-4,5-dihydro-1H-pyrazole-1-carboximidamides that proceeds via the efficient reaction of chalcones with aminoguanidine hydrochloride under clean conditions is described.


Asunto(s)
Amidas/síntesis química , Amidas/efectos de la radiación , Chalconas/química , Chalconas/efectos de la radiación , Guanidinas/química , Guanidinas/efectos de la radiación , Sonicación/métodos , Dosis de Radiación
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