RESUMEN
Major changes in the technological, economic, and social behavior of Middle Pleistocene hominins occurred at the onset of the Middle Paleolithic, 400-200 ka. However, until recently it was not possible to establish when, where, and how certain forms of Middle Paleolithic behavior appeared and spread into Southeastern Europe, mainly owing to gaps in the Paleolithic record. Here we report new results of dating, material culture, and the archaeological context of finds from the Balanica Cave Complex in Sicevo (Serbia). Two methods-thermoluminescence and electron spin resonance-were used to date the sequence. The geoarchaeological context was examined through sedimentology, micromorphology, and spatial analysis. Microfaunal remains were used to constrain the dates within an ecological zone, whereas macrofauna was analyzed for taxonomy and taphonomy to examine the source of accumulation and hominin behavior. Technological and typological features of the lithic assemblage were used to characterize lithic production at the site. Materials recovered from Layer 3 in Velika Balanica and from Layer 2 in Mala Balanica, both dated to MIS 9-7, include a distinctive set of archaeological assemblages which resemble contemporaneous Yabrudian assemblages from the Levant in important ways, and which are unlike contemporary material from the surrounding regions. In Velika Balanica, the lithic assemblages are associated with a large fireplace containing evidence of human activities similar to those from Qesem Cave (Israel). Dental remains uncovered in the same layer are consistent with Neanderthals. These findings suggest that the end of the Middle Pleistocene (before 300-240 ka) saw population movement and/or cultural transmission between Southwest Asia and the Balkans, which led eventually to a transfer of technology between Middle Eastern and European hominin populations and contributed to the shaping of Neanderthal behaviors throughout the eastern and northern Mediterranean.
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Hominidae , Hombre de Neandertal , Animales , Arqueología , Peninsula Balcánica , Cuevas , Fósiles , Humanos , SerbiaRESUMEN
Dry MeOH extracts of the twig barks of Pyrus communis subsp. pyraster, P.â spinosa and their hybrid P.×jordanovii nothosubsp. velenovskyi, collected in wild in Serbia, were analyzed. By LC/MS, the contents of arbutin (99.9-131.0â mg/g), chlorogenic acid (2.2-6.3â mg/g), catechin (1.0-5.3â mg/g) and total dimeric and trimeric procyanidins (42.2-61.3â mg/g), including procyanidin B2 (8.9-17.2â mg/g), were determined. Colorimetrically, high contents of total phenolics (436.2-533.4â mg GAE/g) and tannins (339.4-425.7â mg GAE/g), as well as strong total antioxidant activities (FRAP values 4.5-5.9â mmol Fe2+ /g), and DPPH (SC50 =6.6-7.1â µg/ml) and hydroxyl radical (SC50 =447.1-727.7â µg/ml) scavenging abilities were revealed. Inâ vitro, all extracts exhibited notable inhibition of α-amylase (IC50 =310.8-617.7â µg/ml) and particularly strong inhibition of α-glucosidase (IC50 =2.1-3.7â µg/ml). Molecular docking predicted that among identified compounds procyanidin B2 is the best inhibitor of these carbohydrate-digesting enzymes. Obtained results showed that the barks of investigated Pyrus hybrid and its parent taxa have similar composition and bioactivity.
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Antioxidantes/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Fenoles/farmacología , Extractos Vegetales/farmacología , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/metabolismo , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Modelos Moleculares , Fenoles/química , Fenoles/aislamiento & purificación , Picratos/antagonistas & inhibidores , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Pyrus/química , alfa-Amilasas/metabolismoRESUMEN
As soil cadmium (Cd) contamination becomes a serious concern and one of the significant environmental pollution issues all over the world, knowledge of the basic chemistry, origin, inputs, sources, quantity, chemical forms, reactions, as well as the fate and transport of Cd in different types of soil is crucial for better understanding Cd bioavailability, health risks and remedial options. This study aimed to increase the current knowledge on the complex interdependence between the factors affecting behavior, transport and fate of Cd in the soil and to test and compare the performance of the stabilization agents in different soil types. Soils demonstrated various sorption affinity and capacity for Cd accumulation, which proved to be positively correlated with soil pH and the cation exchange capacity (CEC). With increasing levels of contamination, sequential extraction analysis showed the highest increase of relative Cd amounts in the exchangeable fraction regardless of the soil properties, suggesting that added Cd is principally associated with the easily accessible and mobile fraction. For different initial Cd concentrations and soil types, Cd sorption reached the quasi-equilibrium within 24â¯h of contact. Prolonged aging (two months) influenced the natural stabilization of Cd in all types of soil, but only at low contamination level. The application of both, conventional (slaked lime Ca(OH)2) and alternative phosphate-rich (annealed bovine bones B400) amendments, resulted in Cd relocation and reduction of exchangeable Cd content. Although the effect was smaller when apatite amendment was utilized, observed re-distribution of Cd to more stable soil fractions is preferable for achieving long-term stabilization. Cd concentrations extracted in exchangeable and acid soluble fractions after the treatments of contaminated soil samples suggest that the practical applicability of in situ immobilization depends on the soil properties and the level of contamination, as well as that effect, should be monitored for the possible re-mobilization of Cd.
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Cadmio/análisis , Hidróxido de Calcio/química , Fertilizantes/análisis , Fosfatos/análisis , Contaminantes del Suelo/análisis , Suelo/química , Animales , Disponibilidad Biológica , Restauración y Remediación Ambiental , Factores de TiempoRESUMEN
The objective of the present study was to determine the impact of cadmium (Cd) concentration in the soil on its uptake by tobacco plants, and to compare the ability of diverse extraction procedures for determining Cd bioavailability and predicting soil-to-plant transfer and Cd plant concentrations. The pseudo-total digestion procedure, modified Tessier sequential extraction and six standard single-extraction tests for estimation of metal mobility and bioavailability were used for the leaching of Cd from a native soil, as well as samples artificially contaminated over a wide range of Cd concentrations. The results of various leaching tests were compared between each other, as well as with the amounts of Cd taken up by tobacco plants in pot experiments. In the native soil sample, most of the Cd was found in fractions not readily available under natural conditions, but with increasing pollution level, Cd amounts in readily available forms increased. With increasing concentrations of Cd in the soil, the quantity of pollutant taken up in tobacco also increased, while the transfer factor (TF) decreased. Linear and non-linear empirical models were developed for predicting the uptake of Cd by tobacco plants based on the results of selected leaching tests. The non-linear equations for ISO 14870 (diethylenetriaminepentaacetic acid extraction - DTPA), ISO/TS 21268-2 (CaCl2 leaching procedure), US EPA 1311 (toxicity characteristic leaching procedure - TCLP) single step extractions, and the sum of the first two fractions of the sequential extraction, exhibited the best correlation with the experimentally determined concentrations of Cd in plants over the entire range of pollutant concentrations. This approach can improve and facilitate the assessment of human exposure to Cd by tobacco smoking, but may also have wider applicability in predicting soil-to-plant transfer.
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Cadmio/análisis , Modelos Teóricos , Nicotiana/química , Contaminantes del Suelo/análisis , Suelo/química , Disponibilidad Biológica , Cadmio/metabolismo , Humanos , Valor Predictivo de las Pruebas , Contaminantes del Suelo/metabolismo , Nicotiana/crecimiento & desarrolloRESUMEN
Pulmonary artery intimal sarcoma (PAS) is a rare mesenchymal tumor mostly diagnosed in middle-aged women. In a 63-year-old female, the radiological findings showed cavitation in the left upper lobe of the lung and infiltrative tumor mass around the left pulmonary artery. PAS consisted of small, round tumor cells with about 80% of mitotic activity and with myxoid background and specific immunoprofile and diagnosed as undifferentiated sarcoma with round cell features type. The final diagnosis of PAS was established according to the pathohistological, chest computed tomography scan, and surgery finding.
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Diabetes is characterized by a deficit in the number of functional pancreatic ß-cells. Understanding the mechanisms that stimulate neogenesis of ß-cells should contribute to improved maintenance of ß-cell mass. Chemokine CXCL12 has recently become established as a novel ß-cell growth factor, however the mechanisms controlling its expression require clarification. We investigated the proteins involved in the transcriptional regulation of the rat ß-cell CXCL12 gene (Cxcl12). Using the electrophoretic mobility shift assay and chromatin immunoprecipitation, we established the in vitro and in vivo binding of C/EBPß, C/EBPα, STAT3, p53, FOXO3a, and HMG I/Y to the Cxcl12 promoter. Co-immunoprecipitation experiments revealed protein-protein interactions between YY1 and PARP-1, FOXO3a and PARP-1, Sp1 and PARP-1, p53 and PARP-1, C/EBPß and PARP-1, YY1 and p53, YY1 and FOXO3a, p53 and FOXO3a, Sp1 and FOXO3a, C/EBPß and FOXO3a, C/EBPα and FOXO3a, Sp1 and STAT3. Our data lay the foundation for research into the interplay of signaling pathways that determine the ß-cell Cxcl12 expression profile.
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Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Quimiocina CXCL12/genética , Células Secretoras de Insulina/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Sitios de Unión , Proteína beta Potenciadora de Unión a CCAAT/genética , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Ensayo de Cambio de Movilidad Electroforética , Regulación de la Expresión Génica , Regiones Promotoras Genéticas , Ratas , Factor de Transcripción STAT3/genética , Activación TranscripcionalRESUMEN
Glutathione (GSH) is a linchpin of cellular defences in plants and animals with physiologically-important roles in the protection of cells from biotic and abiotic stresses. Moreover, glutathione participates in numerous metabolic and cell signalling processes including protein synthesis and amino acid transport, DNA repair and the control of cell division and cell suicide programmes. While it is has long been appreciated that cellular glutathione homeostasis is regulated by factors such as synthesis, degradation, transport, and redox turnover, relatively little attention has been paid to the influence of the intracellular partitioning on glutathione and its implications for the regulation of cell functions and signalling. We focus here on the functions of glutathione in the nucleus, particularly in relation to physiological processes such as the cell cycle and cell death. The sequestration of GSH in the nucleus of proliferating animal and plant cells suggests that common redox mechanisms exist for DNA regulation in G1 and mitosis in all eukaryotes. We propose that glutathione acts as "redox sensor" at the onset of DNA synthesis with roles in maintaining the nuclear architecture by providing the appropriate redox environment for the DNA replication and safeguarding DNA integrity. In addition, nuclear GSH may be involved in epigenetic phenomena and in the control of nuclear protein degradation by nuclear proteasome. Moreover, by increasing the nuclear GSH pool and reducing disulfide bonds on nuclear proteins at the onset of cell proliferation, an appropriate redox environment is generated for the stimulation of chromatin decompaction. This article is part of a Special Issue entitled Cellular functions of glutathione.
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Núcleo Celular/metabolismo , Glutatión/metabolismo , Animales , Arabidopsis/genética , Arabidopsis/metabolismo , Ciclo Celular/fisiología , Muerte Celular/fisiología , Procesos de Crecimiento Celular/fisiología , Núcleo Celular/genética , Replicación del ADN , Glutatión/genética , Humanos , Oxidación-Reducción , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
Complete spontaneous regression of multiple melanocytic nevi after melanoma is an extremely rare phenomenon. We report 3 cases of patients with a history of melanoma that showed regression of almost all melanocytic nevi over time. One of the patients had 2 simultaneous primary cutaneous melanomas without metastasis. In the other 2 patients, regression of the melanocytic nevi was seen after the development of metastasis in lymph nodes. These patients had spontaneously developed an efficient immune response against melanocytes, and they would represent paradigmatic examples of the spontaneous immune responses in melanoma patients. Better understanding of the mechanisms involved in the complete regression of melanocytic lesions would lead to a better selection of melanoma patients for immunotherapy.
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Melanocitos/patología , Melanoma/secundario , Regresión Neoplásica Espontánea , Nevo Pigmentado/patología , Neoplasias Cutáneas/patología , Adolescente , Adulto , Biopsia , Dermoscopía , Progresión de la Enfermedad , Resultado Fatal , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Masculino , Melanocitos/inmunología , Melanoma/inmunología , Melanoma/cirugía , Nevo Pigmentado/inmunología , Nevo Pigmentado/cirugía , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/cirugía , Factores de Tiempo , Resultado del Tratamiento , Melanoma Cutáneo MalignoRESUMEN
The present study aimed to investigate the effects of the treatment with a-lipoic acid (LA), a naturally occurring compound possessing antioxidant activity, on liver oxidant stress in a rat model of streptozotocin (STZ)-induced diabetes by examining potential mechanistic points that influence changes in the expression of antioxidant enzymes such as catalase (CAT) and CuZn/Mn superoxide dismutase(s) (SOD). LA was administered for 4 weeks by daily intraperitoneal injections (10 mg/kg) to STZ-induced diabetic rats, starting from the last STZ treatment. LA administration practically normalised the activities of the indicators of hepatocellular injury, alanine and aspartate aminotransferases, and lowered oxidative stress, as observed by the thiobarbituric acid-reactive substance assay, restored the reduced glutathione:glutathione disulphide ratio and increased the protein sulfhydryl group content. The lower level of DNA damage detected by the comet assay revealed that LA reduced cytotoxic signalling, exerting a hepatoprotective effect. The LA-treated diabetic rats displayed restored specific enzymatic activities of CAT, CuZnSOD and MnSOD. Quantitative real-time PCR analysis showed that LA restored CAT gene expression to its physiological level and increased CuZnSOD gene expression, but the gene expression of MnSOD remained at the diabetic level. Although the amounts of CAT and CuZnSOD protein expression returned to the control levels, the protein expression of MnSOD was elevated. These results suggested that LA administration affected CAT and CuZnSOD expression mainly at the transcriptional level, and MnSOD expression at the post-transcriptional level. The observed LA-promoted decrease in the O-GlcNAcylation of extracellular signal-regulated kinase, protein 38 kinase, NF-kB, CCAAT/enhancer-binding protein and the antioxidative enzymes themselves in diabetic rats suggests that the regulatory mechanisms that supported the changes in antioxidative enzyme expression were also influenced by post-translational mechanisms.
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Antioxidantes/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Hígado/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Ácido Tióctico/uso terapéutico , Aminoacilación , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Factor de Unión a CCAAT , Catalasa/metabolismo , Daño del ADN/efectos de los fármacos , Diabetes Mellitus Experimental/metabolismo , Glutatión/metabolismo , Disulfuro de Glutatión/metabolismo , Hígado/metabolismo , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Oxidación-Reducción , Ratas , Ratas Wistar , Compuestos de Sulfhidrilo/metabolismo , Superóxido Dismutasa/metabolismo , Ácido Tióctico/farmacología , Transaminasas/metabolismo , Transcripción Genética/efectos de los fármacosRESUMEN
PURPOSE: The combined hyperglycemia lowering and antioxidant actions of α-lipoic acid (LA) contribute to its usefulness in preventing renal injury and other diabetic complications. The precise mechanisms by which LA alters diabetic oxidative renal injury are not known. We hypothesized that LA through its hypoglycemic effect lowers O-GlcNAcylation which influences the expression and activities of antioxidant enzymes which assume important roles in preventing diabetes-induced oxidative renal injury. METHODS: An experimental model of diabetes was induced in rats by the administration of 40 mg/kg streptozotocin (STZ) intraperitoneally (i.p.) for five consecutive days. LA was applied at a dose of 10 mg/kg i.p. for 4 weeks, starting from the last day of STZ administration. RESULTS: An improved glycemic status of LA-treated diabetic rats was accompanied by a significant suppression of oxidative stress and a reduction of oxidative damage of lipids, proteins and DNA. LA treatment normalized CuZn-superoxide dismutase (SOD) and catalase activities in renal tissue of diabetic rats. These changes were allied with upregulated gene expression and lower levels of O-GlcNA glycosylation. The accompanying increase in MnSOD activity was only linked with upregulated gene expression. The observed antioxidant enzyme gene regulation was accompanied by nuclear translocation of Nuclear factor-erythroid-2-related factor 2 (Nrf2), enhanced expression of heat shock proteins (HSPs) and by reduction in O-GlcNAcylation of HSP90, HSP70, and extracellular regulated kinase and p38. CONCLUSION: α-Lipoic acid administration activates a coordinated cytoprotective response against diabetes-induced oxidative injury in kidney tissue through an O-GlcNAc-dependent mechanism.
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Acetilglucosamina/metabolismo , Antioxidantes/metabolismo , Diabetes Mellitus Experimental/metabolismo , Riñón/efectos de los fármacos , Ácido Tióctico/farmacología , Animales , Glucemia/metabolismo , Catalasa/metabolismo , Daño del ADN/efectos de los fármacos , Diabetes Mellitus Experimental/inducido químicamente , Glutatión/metabolismo , Glicosilación , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Proteínas HSP90 de Choque Térmico/genética , Proteínas HSP90 de Choque Térmico/metabolismo , Hiperglucemia/tratamiento farmacológico , Riñón/enzimología , Enfermedades Renales/prevención & control , Peroxidación de Lípido/efectos de los fármacos , Masculino , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Transducción de Señal , Estreptozocina , Superóxido Dismutasa/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND: Three pure compounds that naturally occur in plants were of particular interest to our study regarding the possibility of using them as food preservatives: p-coumaric acid (found in peanuts, tomatoes, carrots, garlic, wine, vinegar, etc.), caffeic acid (found in argan oil, oats, wheat, rice and olive oil) and rutin (found in asparagus, citrus fruits, berries, apple, apricot, asparagus, beef and beer). In the following study we investigated in situ antioxidant and antimicrobial activities of three pure compounds, namely caffeic acid, p-coumaric acid and rutin, naturally occurring in plants. RESULTS: Two food systems were used in order to obtain information on how these compounds react in actual food systems rather than microbiological media. The results indicated good antioxidant activity in in situ food systems. For tested phenolic compounds it was further shown that they successively inhibited the development of the isolated food contaminant Staphylococcus aureus in chicken soup. Panelist found that organoleptic characteristics of chicken soup and pork meat improved after treatment with phenolics. CONCLUSION: Our findings alone, along with the potential use of phenolic compounds that are widespread in nature, may imply their potential use as preservatives in the food industry.
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Antiinfecciosos , Antioxidantes , Ácidos Cafeicos , Ácidos Cumáricos , Plantas/química , Rutina , Animales , Ácidos Cafeicos/farmacología , Pollos , Ácidos Cumáricos/farmacología , Microbiología de Alimentos/métodos , Conservantes de Alimentos , Carne/microbiología , Propionatos , Rutina/farmacología , Sensación , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , PorcinosRESUMEN
Pancreatic ß-cell death or dysfunction mediated by oxidative stress underlies the development and progression of diabetes mellitus. In the present study, we tested extracts from the edible mushroom Lactarius deterrimus and the chestnut Castanea sativa, as well as their mixture (MIX Ld/Cs), for potential beneficial effects on streptozotocin (STZ)-induced pancreatic ß-cell death. Analysis of chelating effects, reducing power and radical-scavenging assays revealed strong antioxidant effects of the C. sativa extract and MIX Ld/Cs, while the L. deterrimus extract displayed a weak to moderate effect. The antioxidative effect of the chestnut extract corresponds with the high content of phenolics and flavonoids identified by HPLC analysis. In contrast, the mushroom extract contains relatively small amounts of phenols and flavonoids. However, both extracts, and especially their combination MIX Ld/Cs, increased cell viability after the STZ treatment as a result of a significant reduction of DNA damage and improved redox status. The chestnut extract and MIX Ld/Cs significantly lowered the STZ-induced increases in superoxide dismutase and catalase activities, while the mushroom extract had no impact on the activities of these antioxidant enzymes. However, the L. deterrimus extract exhibited good NO-scavenging activity. Different mechanisms that underlie antioxidant effects of the mushroom and chestnut extracts were discussed. When combined as in the MIX Ld/Cs, the extracts exhibited diverse but synergistic actions that ultimately exerted beneficial and protective effects against STZ-induced pancreatic ß-cell death.
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Agaricales/química , Antioxidantes/farmacología , Productos Biológicos/farmacología , Fagaceae/química , Células Secretoras de Insulina/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Bosnia y Herzegovina , Línea Celular , Supervivencia Celular/efectos de los fármacos , Croacia , Daño del ADN/efectos de los fármacos , Flavonoides/análisis , Frutas/química , Cuerpos Fructíferos de los Hongos/química , Células Secretoras de Insulina/enzimología , Células Secretoras de Insulina/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Óxido Nítrico/antagonistas & inhibidores , Oxidorreductasas/antagonistas & inhibidores , Oxidorreductasas/metabolismo , Fenoles/análisis , Ratas , Estreptozocina/antagonistas & inhibidores , Estreptozocina/toxicidadRESUMEN
Nuts and seeds are an indispensable part of the plant-based diet, which is becoming increasingly popular due to the evidence of their health benefits and contribution to sustainability and planetary health. Since the health effects of consuming nuts and seeds directly depend on their nutritional composition and consumed amount, it is essential to know the exact chemical composition of each nut and seed so that appropriate dietary interventions can be adequately planned. The present study aimed to examine the chemical composition of nuts and seeds obtained from the Serbian market and to highlight the similarities and differences in their nutritional composition. In twenty-four samples of nuts and seeds, the content of total lipids, including fatty acid profile, total proteins, including amino acid profile, total carbohydrates (sugars and fibers), phytosterols, and minerals were determined. Content of selected nutrients in grams (g) or milligrams (mg) of nuts and seeds was expressed in one portion (28 g) and as a percentage of contribution of Reference Intakes (% RI) and Dietary Reference Value (% DRV) for macronutrients and minerals, respectively. Some of the seed representatives appeared to be rich sources of essential omega-3 fatty acid, α-linolenic acid (ALA) (flax seed vs. walnut, 6.50 vs. 0.56 g per portion, respectively), dietary fibers (chia seed vs. raw almond, 10.6 vs. 3.4 g per portion, respectively), calcium (black sesame seed vs. almond roasted, 32.4% NRV vs. 8.1% NRV per portion, respectively), magnesium (hemp seed vs. Brazil nut, 38.3% NRV vs. 27.8% NRV per portion, respectively), and zinc (hemp seed vs. pine nut, 21.4% NRV vs. 17.6% NRV per portion, respectively). Our results highlighted the crucial role of seeds in the diet, especially as a better source of nutrients compared to nuts. Furthermore, it was seen that nuts and seeds are different and complementary in their composition. Thus, in order to meet the needs for certain nutrients for which nuts and seeds are used as dietary sources (essential fatty acids, minerals, dietary fibers), it would be beneficial to combine both nuts and seeds as a part of a healthy dietary pattern.
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Organic synthesis could be very demanding, usually due to difficulties related to the separation of main reaction products from by-products. Steroidal compounds could have similar lipophilicity, which is mostly based on the lipophilicity of the steroidal core. This causes many problems during purification, i.e. in obtaining a pure single steroidal compound. In this research, a group of bile acid derivatives were subjected to HPLC analysis using four experimental systems, which presented combinations of C18 and F5 columns with methanol-water and acetonitrile-water as mobile phases. Retention parameters and retention order of the compounds were established and indicated that all experimental systems could be applicable in order to separate and/or purify some individual compounds or a mixture of a few compounds. However, the only experimental system that could separate a mixture of all investigated derivatives proved to be a C18 column with acetonitrile-water as a mobile phase. Since complex interactions between F5 column and the analytes exist, molecular surface polarity (MSP) was tested as a lipophilicity parameter, and also compared with logP using multivariate statistics. Retention parameters obtained on F5 column were used as descriptors, both with MSP and with logP, concluding that logP has shown to be a better lipophilicity descriptor.
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Ácidos y Sales Biliares , Agua , Acetonitrilos , Cromatografía Líquida de Alta Presión , Estudios de Factibilidad , EsteroidesRESUMEN
Cellular redox homeostasis and signalling are important in progression of the eukaryotic cell cycle. In animals, the low-molecular-weight thiol tripeptide glutathione (GSH) is recruited into the nucleus early in the cell proliferation cycle. To determine whether a similar process occurs in plants, we studied cell proliferation in Arabidopsis thaliana. We show that GSH co-localizes with nuclear DNA during the proliferation of A. thaliana cells in culture. Moreover, GSH localization in the nucleus was observed in dividing pericycle cells of the lateral root meristem. There was pronounced accumulation of GSH in the nucleus at points in the growth cycle at which a high percentage of the cells were in G(1) phase, as identified by flow cytometry and marker transcripts. Recruitment of GSH into the nucleus led to a high abundance of GSH in the nucleus (GSHn) and severe depletion of the cytoplasmic GSH pool (GSHc). Sequestration of GSH in the nucleus was accompanied by significant decreases in transcripts associated with oxidative signalling and stress tolerance, and an increase in the abundance of hydrogen peroxide, an effect that was enhanced when the dividing cells were treated with salicylic acid. Total cellular GSH and the abundance of GSH1 and GSH2 transcripts increased after the initial recruitment of GSH into the nucleus. We conclude that GSH recruitment into the nucleus during cell proliferation has a profound effect on the whole-cell redox state. High GSHn levels trigger redox adjustments in the cytoplasm, favouring decreased oxidative signalling and enhanced GSH synthesis.
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Arabidopsis/citología , Núcleo Celular/metabolismo , Proliferación Celular , Glutatión/metabolismo , Homeostasis , Arabidopsis/fisiología , Ciclo Celular , Células Cultivadas , Peróxido de Hidrógeno/metabolismo , Microscopía Confocal , Análisis de Secuencia por Matrices de Oligonucleótidos , Oxidación-ReducciónRESUMEN
To examine the protective potential of the Cotinus coggygria Scop. methanol extract, Wistar rats were treated with the hepatotoxic compound pyrogallol, which possesses a potent ability to generate free radicals and induce oxidative stress. The ability of the extract to counteract the oxidative stress was examined in rats that were injected with the extract intraperitoneally (500 mg·(kg body weight)(-1)) either 2 or 12 h before the pyrogallol treatment. The extract possesses a reducing activity in vitro and an ability to chelate the ferrous ion both in vivo and in vitro. Application of the extract prior to pyrogallol treatment led to a decrease in the levels of thiobarbituric acid-reactive substances, aspartate aminotransferase, and alanine aminotransferase, increased activities of antioxidant enzymes and attenuation of DNA damage, as well as increased Akt activity and inhibition of NF-κB protein expression. Treatment with the extract 12 h prior to pyrogallol administration was more effective in suppressing pyrogallol-induced oxidative damage than the 2 h pretreatment. Extract administration promoted an increase in acute phase reactants haptoglobin and α(2)-macroglobulin that was short of a full-fledged acute phase response. Administration of the extract considerably improved the markers of oxidative stress, thus revealing a potential hepatoprotective activity. Our results suggest that Akt activation, NF-κB inhibition, and induction of the acute phase play important roles in mediating hepatic protection by the extract. The greater effectiveness of the 12 h pretreatment with extract points to the important role that preconditioning assumes in improving resistance to subsequent exposure to oxidative stress.
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Anacardiaceae , Antioxidantes/farmacología , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Pirogalol/toxicidad , Animales , Catalasa/metabolismo , Glutatión/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/enzimología , Masculino , FN-kappa B/metabolismo , Oxidación-Reducción/efectos de los fármacos , Tallos de la Planta , Sustancias Protectoras/farmacología , Pirogalol/farmacología , Ratas , Ratas Wistar , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Factores de TiempoRESUMEN
The complex antioxidant network of plant and animal cells has the thiol tripeptide GSH at its centre to buffer ROS (reactive oxygen species) and facilitate cellular redox signalling which controls growth, development and defence. GSH is found in nearly every compartment of the cell, including the nucleus. Transport between the different intracellular compartments is pivotal to the regulation of cell proliferation. GSH co-localizes with nuclear DNA at the early stages of proliferation in plant and animal cells. Moreover, GSH recruitment and sequestration in the nucleus during the G1- and S-phases of the cell cycle has a profound impact on cellular redox homoeostasis and on gene expression. For example, the abundance of transcripts encoding stress and defence proteins is decreased when GSH is sequestered in the nucleus. The functions of GSHn (nuclear GSH) are considered in the present review in the context of whole-cell redox homoeostasis and signalling, as well as potential mechanisms for GSH transport into the nucleus. We also discuss the possible role of GSHn as a regulator of nuclear proteins such as histones and PARP [poly(ADP-ribose) polymerase] that control genetic and epigenetic events. In this way, a high level of GSH in the nucleus may not only have an immediate effect on gene expression patterns, but also contribute to how cells retain a memory of the cellular redox environment that is transferred through generations.
Asunto(s)
Ciclo Celular , Núcleo Celular/metabolismo , Glutatión/metabolismo , Animales , Compartimento Celular , Proliferación Celular , Glutatión/biosíntesis , Humanos , Oxidación-ReducciónRESUMEN
The toxicity of hybrid nanoparticles, consisting of non-toxic components, zirconium dioxide nanoparticles (ZrO2 NPs), and caffeic acid (CA), was examined against four different cell lines (HTR-8 SV/Neo, JEG-3, JAR, and HeLa). Stable aqueous ZrO2 sol, synthesized by forced hydrolysis, consists of 3-4 nm in size primary particles organized in 30-60 nm in size snowflake-like particles, as determined by transmission electron microscopy and direct light scattering measurements. The surface modification of ZrO2 NPs with CA leads to the formation of an interfacial charge transfer (ICT) complex followed by the appearance of absorption in the visible spectral range. The spectroscopic observations are complemented with the density functional theory calculations using a cluster model. The ZrO2 NPs and CA are non-toxic against four different cell lines in investigated concentration range. Also, ZrO2 NPs promote the proliferation of HTR-8 SV/Neo, JAR, and HeLa cells. On the other hand, hybrid ZrO2/CA NPs induced a significant reduction of the viability of the JEG-3 cells (39 %) for the high concentration of components (1.6 mM ZrO2 and 0.4 mM CA).
Asunto(s)
Ácidos Cafeicos/toxicidad , Nanopartículas del Metal/toxicidad , Placenta/efectos de los fármacos , Circonio/toxicidad , Ácidos Cafeicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Teoría Funcional de la Densidad , Femenino , Humanos , Nanopartículas del Metal/química , Modelos Químicos , Tamaño de la Partícula , Placenta/patología , Embarazo , Pruebas de Toxicidad , Circonio/químicaRESUMEN
Benign epithelial tumors of the lung are uncommon and can represent a diagnostic challenge. Herein, we describe one such emblematic case. A 59-year-old former smoker male was admitted to the hospital complaining of cough for a long time. A radiological examination showed a centrally excavated mass strictly connected to the visceral pleura. The patient underwent tumorectomy. At gross examination, the tumor was composed of solid and cystic areas containing clear liquid. Histological examination highlighted a sub-pleural encapsulated tumor, with foci of capsular invasion, characterized by a single layer of columnar and cuboidal epithelial cells lining moderately cellular fibro-vascular cores. A wide spectrum of immunohistochemical markers was performed. The final diagnosis was suggestive of a peripheral pulmonary papillary tumor of undetermined malignant potential. At the last follow-up, six years after surgery, no recurrence or metastases were described. Reporting this case, we would like to point out the existence of these rare entities that should be taken into account in the diagnostic process, thus avoiding potential misdiagnosis. Moreover, the presence of capsular invasion should be better investigated in order to reconsider the exact terminology of the tumor and the classification of its malignant potential.
RESUMEN
In this paper we argue that predictive processing (PP) theory cannot account for the phenomenon of affect-biased attention - prioritized attention to stimuli that are affectively salient because of their associations with reward or punishment. Specifically, the PP hypothesis that selective attention can be analyzed in terms of the optimization of precision expectations cannot accommodate affect-biased attention; affectively salient stimuli can capture our attention even when precision expectations are low. We review the prospects of three recent attempts to accommodate affect with tools internal to PP theory: Miller and Clark's (2018) embodied inference; Seth's (2013) interoceptive inference; and Joffily and Coricelli's (2013) rate of change of free energy. In each case we argue that the account does not resolve the challenge from affect-biased attention. For this reason, we conclude that prediction error minimization is not sufficient to explain all mental phenomena, contrary to the claim that the PP framework provides a unified theory of all mental phenomena or the brain's cognitive functioning. Nevertheless, we suggest that empirical investigation of the interaction between affective salience and precision expectations should prove helpful in understanding the limits of PP theory, and may provide new directions for the application of a Bayesian perspective to perception.