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1.
Pharmaceutics ; 16(7)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39065570

RESUMEN

Breast cancer is the second most common type of cancer in the world. Polyphenols can act at all stages of carcinogenesis and oxyresveratrol (OXY) promising anticancer properties, mainly associated with chemotherapy drugs. The aim of this study was to investigate the effect of OXY with doxorubicin (DOX) or melphalan (MEL), either isolated or associated, in MCF-7 and MDA-MB-231 breast cancer cells. Our results showed that OXY, DOX, and MEL presented cytotoxicity, in addition to altering cell morphology. The synergistic association of OXY + DOX and OXY + MEL reduced the cell viability in a dose-dependent manner. The OXY, DOX, or MEL and associations were able to alter the ROS production, ∆Ψm, and cell cycle; DOX and OXY + DOX led the cells to necrosis. Furthermore, OXY and OXY + MEL were able to lead the cells to apoptosis and upregulate caspases-3, -7, -8, and -9 in both cells. LC-HRMS showed that 7-deoxidoxorubicinone and doxorubicinol, responsible for the cardiotoxic effect, were not identified in cells treated with the OXY + DOX association. In summary, our results demonstrate for the first time the synergistic effect of OXY with chemotherapeutic agents in breast cancer cells, offering a new strategy for future animal studies.

2.
Toxics ; 12(3)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38535937

RESUMEN

Mercury contamination in the Amazon arising from both natural sources and intensive mining activities in the region is a significant public health concern. This metal is used to separate Au from sediments. Accordingly, this study aimed to assess the impact of mining on mercury contamination in the animal and human populations of the Amazon. This overall objective was pursued through a systematic review of the existing literature to assess the impact of Hg and identify gaps in geographic coverage arising from this assessment. Herein, we employed PECO and PRISMA-ScR protocols to select articles published between 2017 and 2023 based on projected points on a map within the biogeographic boundaries of the Amazon. We found that mercury concentrations increase with trophic levels, reaching high values of 3.7 µg/g in the muscles of predatory fish and 34.9 µg/g in human hair. The mean level of mercury in human hair in the whole (Amazon) region exceeds 6 µg/g, surpassing tolerance levels. Although mining regions show high concentrations of Hg, the highest incidence was observed among populations with fish-based diets. It was concluded that continuous research and monitoring of fish in the region are required in order to accurately assess the risk associated with Hg contamination, especially since fish are the main source of protein in this region.

3.
Toxics ; 11(11)2023 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-37999538

RESUMEN

This study evaluates the use of mercury (Hg) concentrations in fish muscle tissue to determine a species' trophic position (TP) in its environment. A campaign conducted in 2019 along 375 km in the middle Araguaia River basin, Brazil, resulted in 239 organisms from 20 species collected. The highest total mercury (THg) concentrations were found in Pellonacastelnaeana (6.93 µg·g-1, wet weight) and in Triportheus elongatus (3.18 µg·g-1, wet weight), whose TPs were different according to the FishBase database. However, they occupied the same trophic level in this study. The intra-specific comparison showed a difference in Hg concentrations between individuals captured in distinct sites. The study of the biota-sediment accumulation factor (BSAF) showed that spatiality interferes with a species' TP. Statistical analyses revealed that when we used a predicted species' TP based on each individual's size, it explained 72% of the variability in THg concentration across all fish species. Multiple regression analysis confirmed that standard length and FishBase values are positively associated with THg (R2 = 0.943). These results point to Hg as a viable indicator of a fish species' TP since it reflects regional, biological, and environmental factors, as demonstrated here for the middle Araguaia River.

4.
Environ Res ; 238(Pt 2): 117231, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37793585

RESUMEN

The Araguaia River floodplain is an important biogeographic boundary between the two largest South American biomes: the Cerrado (Brazilian Savanna) and the Amazon rainforest. The large-scale degradation due to land use conversion experienced in the Araguaia River watershed represents a potential source of mercury (Hg) transport to aquatic ecosystems. However, more information is needed about the dynamics of Hg distribution in savanna floodplains, including the Araguaia River floodplain. We analyzed total mercury (THg) concentrations in the bottom sediments of 30 lakes connected to the Araguaia River and four tributaries, aiming to evaluate the environment's integrity based on the geoaccumulation index (Igeo) and the ecological risk index (ERI). The principal component analysis was applied to examine associations between Hg concentrations, environmental conditions, and land use intensity among lakes associated with different river systems. We used indicator cokriging to identify areas with a greater probability of Hg pollution and ecological risk associated with land use intensity. The land use data showed the predominance of areas used for pasture in the Araguaia River basin. THg concentrations in the sediments varied between 22.6 and 81.9 ng g-1 (mean: 46.5 ± 17.7 ng g-1). Sediments showed no significant pollution (Igeo: 1.35 - 0.50; Classes 1 and 2) and low to considerable ecological risks (ERI: 23.5-85.1; Classes 1 to 3). THg in bottom sediments was associated with land use, water turbidity and electrical conductivity, and sediment organic matter. The indicator cokriging indicates a moderate to strong spatial dependence between land use intensity and Hg, confirming the contribution of anthropic sources to the increment of ecological risk but also the influence of extrinsic factors (such as environmental conditions, geology, and hydrology). Integrating sediment assessment and land use indices with geostatistical methods proved a valuable tool for identifying priority areas for Hg accumulation at a regional scale.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Mercurio/análisis , Ríos , Lagos , Brasil , Ecosistema , Pradera , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/análisis
5.
Heliyon ; 9(10): e19920, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37771527

RESUMEN

Large-scale oil palm cultivation with intensive pesticide use has been growing worldwide and reached the Brazilian Amazon. The rapid expansion of this crop over the last decade has reached vast areas, including the boundaries of different indigenous lands. This study aimed at assessing the occurrence of pesticide residues in surface and ground waters as well as drainage sediments in the Turé-Mariquita Indigenous Territory, in addition to other nearby indigenous villages in the northeastern state of Pará. Thirty-three (33) water samples were collected from streams, springs and from active and abandoned wells at 19 sampling points, as well as 16 sediment samples at 9 sampling sites both during dry and rainy seasons. In total, 49 environmental samples were taken during fieldworks and subsequently analyzed by means of liquid chromatography and mass-mass spectrometry. The analytical determination of pesticide residues showed the occurrence of three pesticides in the water both from streams and from wells, two of them knowingly used by the oil palm company: glyphosate-based herbicides (GBHs) and endosulfan insecticides. Although the highest glyphosate and endosulfan levels as well as the maximum concentration of glyphosate found in ground water are within the Brazilian environmental regulatory guidelines, all the values for human consumption found in the glyphosate-containing samples are well above the European Union regulatory standards. Our results draw the attention to the risks of biota contamination and human exposure to multiple-pesticide residues.

6.
Sci Rep ; 13(1): 13446, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596331

RESUMEN

Breast cancer is the second most common type of cancer worldwide and the leading cause of cancer death in women. Dietary bioactive compounds may act at different stages of carcinogenesis, including tumor initiation, promotion, and progression. Spices have been used for thousands of years and have many bioactive compounds with chemopreventive and chemotherapeutic properties. Curcumin has a multitude of beneficial biological properties, including anti-inflammatory and anticancer effects. This study investigated the effects of cotreatment with curcumin and the chemotherapeutic drug melphalan in cultured MDA-MB-231 breast cancer cells. When used alone, both curcumin and melphalan had a cytotoxic effect on breast cancer cells. Combined treatment with 11.65 µM of curcumin and 93.95 µM of melphalan (CURC/MEL) reduced cell viability by 28.64% and 72.43% after 24 h and 48 h, respectively. CURC/MEL reduced the number of colony-forming units and increased ROS levels by 1.36-fold. CURC/MEL alter cell cycle progression, induce apoptosis, and upregulate caspases-3, -7, and -9, in MDA-MB-231 cells. Cotreatment with curcumin and melphalan have anti-breast cancer cells effects and represent a promising candidate for clinical testing.


Asunto(s)
Neoplasias de la Mama , Curcumina , Femenino , Humanos , Melfalán/farmacología , Curcumina/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Puntos de Control del Ciclo Celular , Apoptosis
7.
Bull Environ Contam Toxicol ; 107(3): 500-505, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33834282

RESUMEN

Climate change coupled with inappropriate burning practices has increased large-scale wildfires in Brazilian tropical savannahs (Cerrado). Considering that the effects of ash from wildfires on water parameters are scarcely known in tropical savannahs, this study investigated the chemical changes caused by ash in the soft water, commonly used for bioassays. To this end, ash samples were collected immediately following a fire in a Cerrado area (Federal District, Brazil) and put into water (1:10 ash:soft-water m/v) to check physical parameters under laboratory conditions. Major water-extractable elements (K+, SO42-, Ca2+, PO43-, Na+, Mg2+) from ash strongly altered water quality parameters: elevated total dissolved solids and conductivity levels as well as an increase in pH and decrease in dissolved oxygen concentration were reported over the course of the experiment (15 days) compared to control conditions. Our results point out relevant solubilized compounds from ashes which may potentially impact water quality in post-fire scenarios.


Asunto(s)
Incendios , Contaminantes Químicos del Agua , Incendios Forestales , Laboratorios , Contaminantes Químicos del Agua/análisis , Calidad del Agua
8.
An Acad Bras Cienc ; 92(4): e20201181, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33295583

RESUMEN

Leishmaniasis is caused by protozoan parasites belonging to the genus Leishmania and includes cutaneous, mucocutaneous and visceral clinical forms. Drugs currently available for leishmaniasis treatment present high toxicity, and development of parasite resistance. Plants constitute an important source of compounds with leishmanicidal potential. This study aimed to evaluate the anti-Leishmania amazonensis activity of the terpenoid fraction of Eugenia pruniformis leaves (TF-EpL). TF-EpL was active against the promastigote and intracellular amastigote forms of L. amazonensis with IC50(24h) value of 43.60µg/mL and 44.77µg/mL, respectively. TF-EpL altered the cell cycle of the parasite, increasing 2.32-fold the cells in the Sub-G0/G1 phase. TF-EpL also changed the ΔΨm and increased ROS and the number of annexin-V-PI positive promastigotes, which suggests incidental death. ß-sitosterol, ursolic acid, corosolic acid and asiatic acid were isolated from TF-EpL. The results showed the antileishmanial activity of E. pruniformis terpenoids and its potential for further studies as a source of new drugs for leishmaniasis.


Asunto(s)
Antiprotozoarios , Eugenia , Leishmania mexicana , Leishmania , Antiprotozoarios/farmacología , Hojas de la Planta , Terpenos/farmacología
9.
Int J Mol Sci ; 21(15)2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32721999

RESUMEN

Breast cancer is the leading cause of cancer mortality in women worldwide. Conventional cancer treatment is costly and results in many side effects. Dietary bioactive compounds may be a potential source for breast cancer prevention and treatment. In this scenario, the aim of this study was to investigate the effects of the bioactive compounds resveratrol, curcumin and piperine (R-C-P) on MCF-7 breast cancer cells and to associate them to Glyoxalase 1 (GLO1) activity. The findings indicate that R-C-P exhibits cytotoxicity towards MCF-7 cells. R-C-P decreased mitochondrial membrane potential (ΔΨm) by 1.93-, 2.04- and 1.17-fold, respectively. Glutathione and N-acetylcysteine were able to reverse the cytotoxicity of the assessed bioactive compounds in MCF-7 cells. R-C-P reduced GLO1 activity by 1.36-, 1.92- and 1.31-fold, respectively. R-C-P in the presence of antimycin A led to 1.98-, 1.65- and 2.16-fold decreases in D-lactate levels after 2 h of treatment, respectively. Glyoxal and methylglyoxal presented cytotoxic effects on MCF-7 cells, with IC50 values of 2.8 and 2.7 mM and of 1.5 and 1.4 mM after 24 and 48 h of treatment, respectively. In conclusion, this study demonstrated that R-C-P results in cytotoxic effects in MCF-7 cells and that this outcome is associated with decreasing GLO1 activity and mitochondrial dysfunction.


Asunto(s)
Alcaloides/farmacología , Benzodioxoles/farmacología , Neoplasias de la Mama/enzimología , Curcumina/farmacología , Lactoilglutatión Liasa/metabolismo , Piperidinas/farmacología , Alcamidas Poliinsaturadas/farmacología , Resveratrol/farmacología , Neoplasias de la Mama/patología , Femenino , Humanos , Células MCF-7 , Potencial de la Membrana Mitocondrial/efectos de los fármacos
10.
J Environ Sci Health B ; 55(9): 794-802, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32586204

RESUMEN

Herbicide use, mainly glyphosate, has been intense in worldwide agriculture, including in the Brazilian Amazon region. This study aimed to validate a method for determining glyphosate and its degradation product, AMPA, and glufosinate by HPLC-FL in 58 water samples collected at the Santarém plateau region (Planalto Santareno), in the western of Pará state, Brazil. The method involves filtration and direct injection in the HPLC-FL for AMPA analysis, or previous concentration (10×) by lyophilization for glufosinate and glyphosate analysis. Analytes were oxidized and complexed with o-phthalaldehyde and 2-mercaptoethanol in a post-column reaction before fluorescence detection. LOQs for AMPA, glyphosate and glufosinate were established at 0.5, 0.2 and 0.3 µg L-1, respectively. A total of 58 samples were collected. Glyphosate and glufosinate were not detected in any of the 30 surface water samples collected in 2015 (

Asunto(s)
Aminobutiratos/análisis , Cromatografía Líquida de Alta Presión/métodos , Glicina/análogos & derivados , Contaminantes Químicos del Agua/análisis , Agua/química , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/análisis , Brasil , Monitoreo del Ambiente , Fluorescencia , Liofilización , Glicina/análisis , Herbicidas/análisis , Límite de Detección , Reproducibilidad de los Resultados , Glifosato
11.
Global Health ; 16(1): 36, 2020 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-32321543

RESUMEN

BACKGROUND: Research on changing dietary practices is rare in lower and middle income countries, and understanding the impact of global economic processes on population health and nutrition is important, especially of rural communities. We analyzed the diet of 22 families in Brasília Legal, a riverside community in the Tapajós River region of the Brazilian Amazon, using nonparametric tests to compare dietary surveys taken in 1999 and 2010. RESULTS: Data from the two surveys show that food obtained through commercial supply chains became more frequent in household diets, corresponding to significant increases in daily consumption of food items rich in energy, protein, and sugar. At the same time, there was a decline in traditional Amazonian food intake. CONCLUSIONS: Comparing these results with household socio-economic characteristics and drawing on open-ended interviews, we consider the multiple influences that economic development processes may have had on local diets. The introduction of new income sources and employment opportunities, infrastructural and transportation expansion, as well as environmental change appear to have influenced the observed dietary shifts. Such shifts are likely to have important implications for the nutritional status of communities in the Amazon, highlighting concerning trade-offs between current development trajectories and human health. Public policies and health education programs must urgently consider the interactions between sustainable development priorities in order to address emerging health risks in this rapidly changing region.


Asunto(s)
Composición Familiar , Conducta Alimentaria/psicología , Planificación Social , Adulto , Anciano , Brasil , Femenino , Calidad de los Alimentos , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores Socioeconómicos , Encuestas y Cuestionarios
12.
Sci Rep ; 9(1): 13960, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31562347

RESUMEN

Flotillin-1 and flotillin-2 are highly conserved proteins that localize into cholesterol-rich microdomains in cellular membranes. Flotillins are closely related to the occurrence and development of various types of human cancers. Flotillin-1 is highly expressed in breast cancer, and the high expression level of flotillin-1 is significantly correlated with poorer patient survival. Here we studied the relationship between the formation of lipid rafts and the expression of flotillins and lipids in human breast cancer cells. We used the polyphenol compound resveratrol to alter the structure and function of the plasma membrane. Our data revealed an increase in fatty acids in MCF-7 and MDA-MB-231 cells upon resveratrol treatment. Interestingly, we also found an increase in the expression of both flotillin-1 and flotillin-2 in breast tumor cells after treatment. Resveratrol also induced changes in the pattern of flotillin distribution among detergent-resistant lipid rafts fractions in both cell lines and induced the nuclear translocation of flotillin-2. Since resveratrol has been pointed out as a putative cancer therapy agent, our results could have an impact on the understanding of the effects of resveratrol in tumor cells.


Asunto(s)
Antioxidantes/farmacología , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ácidos Grasos/metabolismo , Proteínas de la Membrana/metabolismo , Resveratrol/farmacología , Neoplasias de la Mama/metabolismo , Membrana Celular/metabolismo , Humanos , Células MCF-7 , Microdominios de Membrana/efectos de los fármacos , Microdominios de Membrana/metabolismo
13.
J Environ Manage ; 203(Pt 1): 522-532, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28841519

RESUMEN

In addition to causing physical degradation and nutrient depletion, erosion of cultivated soils in the Amazon affects aquatic ecosystems through the release of natural soil mercury (Hg) towards lakes and rivers. While traditional agriculture is generally cited as being among the main causes of soil erosion, agroforestry practices are increasingly appreciated for soil conservation. This study was carried out in family farms of the rural Tapajós region (Brazil) and aimed at evaluating soil erosion and associated Hg release for three land uses. Soils, runoff water and eroded sediments were collected at three sites representing a land cover gradient: a recently burnt short-cycle cropping system (SCC), a 2-year-old agroforestry system (AFS) and a mature forest (F). At each site, two PVC soil erosion plots (each composed of three 2 × 5 m isolated subplots) were implemented on steep and moderate slopes respectively. Sampling was done after each of the 20 rain events that occurred during a 1-month study period, in the peak of the 2011 rain season. Runoff volume and rate, as well as eroded soil particles with their Hg and cation concentrations were determined. Total Hg and cation losses were then calculated for each subplot. Erosion processes were dominated by land use type over rainfall or soil slope. Eroded soil particles, as well as the amount of Hg and cations (CaMgK) mobilized at the AFS site were similar to those at the F site, but significantly lower than those at the SCC site (p < 0.0001). Erosion reduction at the AFS site was mainly attributed to the ground cover plants characterizing the recently established system. Moreover, edaphic change throughout AFS and F soil profiles differed from the SCC site. At the latter site, losses of fine particles and Hg were enhanced towards soil surface, while they were less pronounced at the other sites. This study shows that agroforestry systems, even in their early stages of implementation, are characterized by low erosion levels resembling those of local forest environments, thus contributing to the maintenance of soil integrity and to the reduction of Hg and nutrient mobility.


Asunto(s)
Mercurio , Contaminantes del Suelo , Agricultura , Brasil , Agricultura Forestal , Bosques , Suelo
14.
Environ Sci Pollut Res Int ; 24(24): 19671-19682, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28681306

RESUMEN

In a global scenario of climate change, several studies have predicted an increase in fires in different parts of the world. With the occurrence of rains following the fires in the Brazilian savanna (Cerrado biome), the compounds present in ashes may enter aquatic environments and cause adverse effects to these ecosystems. In this context, this study evaluated the potential toxicity of ashes from two areas of Cerrado and an area of pasture, through ecotoxicological bioassays and using three aquatic species from distinct trophic levels, which were exposed to different dilutions of ashes: the microcrustacean Ceriodaphnia dubia, the fish Danio rerio and the mollusc Biomphalaria glabrata. The ashes from the three sampled areas showed higher concentrations of some elements in relation to the soil samples (B, Ca, K, Mg, Mn, P, S, Si, Sr, Zn), but only a small quantity of these compounds was solubilised. Our data showed that all ash samples caused acute toxicity to C. dubia (48hs-LC50 = 13.4 g L-1; 48hs-LC50 = 6.33 g L-1; 48hs-LC50 = 9.73 g L-1 respectively for transition area, pasture, typical cerrado areas), while in relation to D. rerio and B. glabrata, no acute toxicity was observed when they were exposed to ashes from native Cerrado vegetation and pasture areas. Ashes from a transition area showed toxicity for D. rerio (48hs-LC50 = 25.0 g L-1); possibly, this was due to the combination of multiple preponderant inorganic elements of ashes with other organic compounds not analysed, such as polycyclic aromatic hydrocarbons (PAHs). In summary, these results suggest that wildfires may pose risks to zooplankton communities and emphasize the need for more studies to better understand the complexity of the ecological effects of fire on aquatic ecosystems.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Ceniza del Carbón/toxicidad , Pradera , Contaminantes Químicos del Agua/toxicidad , Incendios Forestales , Animales , Brasil , Ceniza del Carbón/análisis , Ecosistema , Ecotoxicología , Metales Pesados/análisis , Metales Pesados/toxicidad , Modelos Teóricos , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Contaminantes Químicos del Agua/análisis
15.
Parasitol Int ; 66(1): 940-947, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27793725

RESUMEN

Extracts of Serjania lethalis A. St.-Hil leaves and stems were tested in order to identify potential agents against Leishmania amazonensis. The hexane fraction (HF) and dichloromethane subfractions (DDF and MDF) showed leishmanicidal effect. The anti-promastigote IC50 values were 10.29 (HF), 11.41 (DDF) and 28.33µg/mL (MDF); whereas those against amastigote were 7.2 (HF), 8.1 (DDF) and 6.5µg/mL (MDF). Among the fractions and subfractions assayed, only HF altered the cell cycle of the parasite, increasing 3-fold the number of cells in the sub-G0/G1 phase. HF also changed the parasite mitochondrial membrane potential (ΔΨm) and the percentage of annexin-V-propidium iodide positive promastigotes. Our evaluations of the IC50 values showed that HF, DDF and MDF decreased NO production in infected macrophages stimulated with IFN-γ and LPS. Moreover, HF increased the production of TNF-α in Leishmania infected macrophages. This paper reports for the first time the leishmanicidal activity of extracts and fractions of Serjania lethalis leaves and also characterizes its leishmanicidal and immunomodulatory properties.


Asunto(s)
Antiprotozoarios/farmacología , Leishmania mexicana/efectos de los fármacos , Macrófagos Peritoneales/efectos de los fármacos , Magnoliopsida/química , Extractos Vegetales/farmacología , Animales , Anexina A5/análisis , Fase G1/efectos de los fármacos , Hexanos/química , Inmunomodulación , Concentración 50 Inhibidora , Interferón gamma/inmunología , Leishmania mexicana/crecimiento & desarrollo , Leishmania mexicana/fisiología , Lipopolisacáridos/inmunología , Macrófagos Peritoneales/inmunología , Macrófagos Peritoneales/parasitología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Cloruro de Metileno/química , Ratones , Óxido Nítrico/biosíntesis , Extractos Vegetales/química , Hojas de la Planta/química , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis
16.
Cad. saúde colet., (Rio J.) ; 24(1): 21-31, jan.-mar. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-781549

RESUMEN

Abstract This study associates blood antioxidants like copper (Cu), manganese (Mn), selenium (Se), zinc (Zn), β-carotene, lycopene and vitamins (A and E) to sociodemographic features and seasonality in communities from the Tapajós River region, Brazilian Amazon. We observed increased Mn, Se and Zn levels compared to the average Brazilian population, whereas this is only the case for β-carotene in the rainy season. Lycopene levels fall within the reference range, although lower than those found in other Brazilian regions. Cu, Se, Zn, β-carotene, lycopene and vitamin E levels vary among seasons. β-carotene, Mn and Se vary among communities. Se and Zn vary with smoking habits and sex, respectively. In addition, β-carotene and vitamins (A and E) are altered by alcohol consumption. Villagers who both farmed and fished present higher Cu and lower β-carotene levels than participants with a single occupation. Vitamin E levels depend upon the individual state of origin. These data provide important baseline information for antioxidant status in this Amazonian riparian population.


Resumo O presente estudo reporta as concentrações plasmáticas dos antioxidantes cobre (Cu), manganês (Mn), selênio (Se), zinco (Zn), β-caroteno, licopeno e vitaminas (A e E) em moradores da região do Rio Tapajós, Pará, Amazônia, e as relaciona com características sociodemográficas e sazonalidade (seca e cheia). Os teores de Mn, Se e Zn foram acima dos valores de referência (VR) e daqueles achados em outras regiões do Brasil, enquanto para o β-caroteno tal achado ocorreu apenas na estação da cheia. Os valores de licopeno foram dentro dos VR, porém abaixo dos achados em outras regiões do Brasil. Os níveis de Cu, Se, Zn, β-caroteno, licopeno e vitamina E variaram entre as estações. Variação intercomunitária foi constatada para β-caroteno, Mn e Se. Os teores de Se e Zn foram alterados, respectivamente, por tabagismo e sexo. Os níveis de β-caroteno e vitaminas (A e E) alteraram-se com o consumo de bebida alcoólica. A vitamina E foi dependente do estado de origem. Participantes que desempenhavam ambas as profissões de agricultor e pescador apresentavam teores de Cu superiores e de β-caroteno inferiores comparativamente àqueles que desempenhavam uma única profissão. Esses dados fornecem informações sobre os teores de antioxidantes para essa população amazônica.

17.
Rev. Soc. Bras. Clín. Méd ; 14(2): 110-113, 2016.
Artículo en Portugués | LILACS | ID: biblio-1257

RESUMEN

A arterite de Takayasu é uma vasculite autoimune rara, que afeta predominantemente a aorta e seus ramos principais, produzindo variados sinais e sintomas, como febre, mialgia, hipertensão, úlceras e isquemia. É mais comum na Ásia e menos frequente nos países ocidentais, acometendo mulheres em idade reprodutiva. As manifestações cutâneas podem estar presentes. Os critérios diagnósticos do American College of Rheumatology incluem idade <40 anos, diminuição dos pulsos braquiais, claudicação de extremidades, diferença de 10mmHg na pressão arterial sistólica de membros superiores, sopros em suclávia e aorta, e alterações angiográficas de aorta e seus arcos principais. Os melhores resultados terapêuticos baseiam-se na corticoterapia associada à imunossupressores como metotrexato. O uso de imunobiológicos é incipiente e carece de estudos para comprovar sua eficácia. A paciente em questão apresentava-se com quadro atípico, manifestando ulceração em couro cabeludo, decorrente de estenose em ramos superficiais da carótida externa. Evoluiu com trombose venosa cerebral e osteomielite, sendo submetida à oxigenoterapia hiperbárica e imunossupressão com 160mg de prednisona.Velocidade de hemossedimentação e proteína C-reativa estavam elevados, mas seu valor isolado carece de especificidade, embora sejam critérios de atividade da doença. A terapêutica com prednisona, metotrexato e anticoagulação com varfarina foi eficiente, pois reduziu a área da lesão em couro cabeludo e minimizou o quadro sistêmico, propiciando melhor qualidade de vida para a paciente.


Takayasu's arteritis is a rare autoimmune vasculitis, which primarily affects the aorta and its main branches, producing varied symptoms and signs, such as fever, myalgia, hypertension, ulcers, and ischemia. It is more common in Asia and less frequente in western countries, affecting women of childbearing age.Cutaneous manifestations may be present. The diagnostic criteria of the American College of Rheumatology include age <40 years,reduction of brachial pulses, extremity claudication, difference of 10 mmHg in systolic blood pressure of upper limbs, murmurs in subclavian artery and aorta, and angiographic changes of the aorta and its main arches. The best therapeutic results are based on corticosteroid therapy associated with immunosuppressants such as methotrexate. The use of immunobiologicals is incipiente and requires studies to prove its effectiveness. The patient presented with an atypical clinical picture, showing ulceration on the scalp as a result of stenosis in superficial branches of the external carotid. She progressed with cerebral venous thrombosis and osteomyelitis, undergoing hyperbaric oxygen therapy and immunosuppression with 160mg of prednisone. Erythrocyte sedimentationrate and C-Reactive Protein were high, but their individual value lacks specificity, although they are criteria for disease activity. Therapy with prednisone, methotrexate, and anticoagulation with warfarin were efficient, because they reduced the area of the lesion on the scalp, and minimized the systemic picture, providing better quality of life for the patient.


Asunto(s)
Humanos , Femenino , Adulto , Cuero Cabelludo/lesiones , Arteritis de Takayasu/diagnóstico , Arteritis de Takayasu/etiología , Arteritis de Takayasu/terapia , Prednisona/uso terapéutico
18.
PLoS One ; 10(10): e0141778, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26517558

RESUMEN

BACKGROUND: Stilbene-based compounds show antitumoral, antioxidant, antihistaminic, anti-inflammatory and antimicrobial activities. Here, we evaluated the effect of the trans-resveratrol analogs, pterostilbene, piceatannol, polydatin and oxyresveratrol, against Leishmania amazonensis. METHODOLOGY/PRINCIPAL FINDINGS: Our results demonstrated a low murine macrophage cytotoxicity of all four analogs. Moreover, pterostilbene, piceatannol, polydatin and oxyresveratrol showed an anti-L. amazonensis activity with IC50 values of 18 µM, 65 µM, 95 µM and 65 µM for promastigotes, respectively. For intracellular amastigotes, the IC50 values of the analogs were 33.2 µM, 45 µM, 29 µM and 30.5 µM, respectively. Among the analogs assayed only piceatannol altered the cell cycle of the parasite, increasing 5-fold the cells in the Sub-G0 phase and decreasing 1.7-fold the cells in the G0-G1 phase. Piceatannol also changed the parasite mitochondrial membrane potential (ΔΨm) and increased the number of annexin-V positive promastigotes, which suggests incidental death. CONCLUSION/SIGNIFICANCE: Among the analogs tested, piceatannol, which is a metabolite of resveratrol, was the more promising candidate for future studies regarding treatment of leishmaniasis.


Asunto(s)
Antiprotozoarios/farmacología , Leishmania/efectos de los fármacos , Estilbenos/farmacología , Animales , Antiprotozoarios/toxicidad , Ciclo Celular/efectos de los fármacos , Macrófagos Peritoneales/parasitología , Potencial de la Membrana Mitocondrial , Ratones , Ratones Endogámicos BALB C , Estilbenos/toxicidad
19.
Acta amaz. ; 45(2): 203-214, abr.-jun. 2015. mapas, tab, graf
Artículo en Inglés | VETINDEX | ID: vti-715259

RESUMEN

Pressures on the Brazilian Amazon forest have been accentuated by agricultural activities practiced by families encouraged to settle in this region in the 1970s by the colonization program of the government. The aims of this study were to analyze the temporal and spatial evolution of land cover and land use (LCLU) in the lower Tapajَs region, in the state of Parل. We contrast 11 watersheds that are generally representative of the colonization dynamics in the region. For this purpose, Landsat satellite images from three different years, 1986, 2001, and 2009, were analyzed with Geographic Information Systems. Individual images were subject to an unsupervised classification using the Maximum Likelihood Classification algorithm available on GRASS. The classes retained for the representation of LCLU in this study were: (1) slightly altered old-growth forest, (2) succession forest, (3) crop land and pasture, and (4) bare soil. The analysis and observation of general trends in eleven watersheds shows that LCLU is changing very rapidly. The average deforestation of old-growth forest in all the watersheds was estimated at more than 30% for the period of 1986 to 2009. The local-scale analysis of watersheds reveals the complexity of LCLU, notably in relation to large changes in the temporal and spatial evolution of watersheds. Proximity to the sprawling city of Itaituba is related to the highest rate of deforestation in two watersheds. The opening of roads such as the Transamazonian highway is associated to the second highest rate of deforestation in three watersheds.(AU)


As pressões sobre a Floresta Amazônica Brasileira têm sido acentuadas por atividades agrícolas de muitas famílias que foram estimuladas a se estabelecer nessa região durante o Programa de Colonização do Governo Federal, na década de 1970. Os objetivos deste presente estudo foram de analisar a evolução espacial e temporal em termos de mudanças de cobertura da terra e uso da terra (CTUT) na região do baixo Tapajós, no Estado do Pará. Contrastam-se 11 bacias que são geralmente representativas do processo de colonização regional por agricultores familiares, e para tanto imagens de satélite Landsat de três diferentes anos (1986, 2001, e 2009) foram analisadas utilizando-se um Sistema de Informação Geográfica. Imagens individuais não-supervisionadas foram classificadas usando-se GRASS, e o algoritmo de classificação de Probabilidade Máxima, para todos os comprimentos de onda do espectro visível e infravermelho (1 a 5 e 7). As classes retidas para a representação do CTUT nesse estudo foram: (1) floresta primária levemente alterada; (2) floresta de sucessão; (3) terra agricultável e pastagem; e (4) solo nu. A análise e observação de tendências gerais em 11 bacias mostram que o CTUT tem mudado rapidamente. O desmatamento médio de floresta primária em todas as bacias foi estimado em mais de 30% no período de 1986 a 2009. A análise em escala local de bacias revela a complexidade do CTUT, notavelmente em relação a grandes mudanças na evolução espacial e temporal das bacias. A proximidade com a cidade de Itaituba, que se encontra em plena expansão, está relacionada com a maior taxa de desmatamento em duas bacias hidrográficas, ao passo que a abertura de estradas, como a Rodovia Transamazônica, está associada à segunda maior taxa de desmatamento em três bacias hidrográficas.(AU)


Asunto(s)
Análisis Espacio-Temporal , Usos del Suelo , Conservación de los Recursos Naturales , 24444 , Medición de Niveles de Agua , Tecnología de Sensores Remotos , Sistemas de Información Geográfica
20.
Acta amaz ; Acta amaz;45(2): 203-214, abr.-jun. 2015. map, tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1455245

RESUMEN

Pressures on the Brazilian Amazon forest have been accentuated by agricultural activities practiced by families encouraged to settle in this region in the 1970s by the colonization program of the government. The aims of this study were to analyze the temporal and spatial evolution of land cover and land use (LCLU) in the lower Tapajَs region, in the state of Parل. We contrast 11 watersheds that are generally representative of the colonization dynamics in the region. For this purpose, Landsat satellite images from three different years, 1986, 2001, and 2009, were analyzed with Geographic Information Systems. Individual images were subject to an unsupervised classification using the Maximum Likelihood Classification algorithm available on GRASS. The classes retained for the representation of LCLU in this study were: (1) slightly altered old-growth forest, (2) succession forest, (3) crop land and pasture, and (4) bare soil. The analysis and observation of general trends in eleven watersheds shows that LCLU is changing very rapidly. The average deforestation of old-growth forest in all the watersheds was estimated at more than 30% for the period of 1986 to 2009. The local-scale analysis of watersheds reveals the complexity of LCLU, notably in relation to large changes in the temporal and spatial evolution of watersheds. Proximity to the sprawling city of Itaituba is related to the highest rate of deforestation in two watersheds. The opening of roads such as the Transamazonian highway is associated to the second highest rate of deforestation in three watersheds.


As pressões sobre a Floresta Amazônica Brasileira têm sido acentuadas por atividades agrícolas de muitas famílias que foram estimuladas a se estabelecer nessa região durante o Programa de Colonização do Governo Federal, na década de 1970. Os objetivos deste presente estudo foram de analisar a evolução espacial e temporal em termos de mudanças de cobertura da terra e uso da terra (CTUT) na região do baixo Tapajós, no Estado do Pará. Contrastam-se 11 bacias que são geralmente representativas do processo de colonização regional por agricultores familiares, e para tanto imagens de satélite Landsat de três diferentes anos (1986, 2001, e 2009) foram analisadas utilizando-se um Sistema de Informação Geográfica. Imagens individuais não-supervisionadas foram classificadas usando-se GRASS, e o algoritmo de classificação de Probabilidade Máxima, para todos os comprimentos de onda do espectro visível e infravermelho (1 a 5 e 7). As classes retidas para a representação do CTUT nesse estudo foram: (1) floresta primária levemente alterada; (2) floresta de sucessão; (3) terra agricultável e pastagem; e (4) solo nu. A análise e observação de tendências gerais em 11 bacias mostram que o CTUT tem mudado rapidamente. O desmatamento médio de floresta primária em todas as bacias foi estimado em mais de 30% no período de 1986 a 2009. A análise em escala local de bacias revela a complexidade do CTUT, notavelmente em relação a grandes mudanças na evolução espacial e temporal das bacias. A proximidade com a cidade de Itaituba, que se encontra em plena expansão, está relacionada com a maior taxa de desmatamento em duas bacias hidrográficas, ao passo que a abertura de estradas, como a Rodovia Transamazônica, está associada à segunda maior taxa de desmatamento em três bacias hidrográficas.


Asunto(s)
Análisis Espacio-Temporal , Conservación de los Recursos Naturales , Producción de Cultivos , Medición de Niveles de Agua , Usos del Suelo , Sistemas de Información Geográfica , Tecnología de Sensores Remotos
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