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991.
Carmen-María López-Saiz Carlos Velázquez Javier Hernández Francisco-Javier Cinco-Moroyoqui Maribel Plascencia-Jatomea Maribel Robles-Sánchez Lorena Machi-Lara Armando Burgos-Hernández 《International journal of molecular sciences》2014,15(12):23555-23570
Shrimp is one of the most popular seafood items worldwide, and has been reported as a source of chemopreventive compounds. In this study, shrimp lipids were separated by solvent partition and further fractionated by semi-preparative RP-HPLC and finally by open column chromatography in order to obtain isolated antiproliferative compounds. Antiproliferative activity was assessed by inhibition of M12.C3.F6 murine cell growth using the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay. The methanolic fraction showed the highest antiproliferative activity; this fraction was separated into 15 different sub-fractions (M1–M15). Fractions M8, M9, M10, M12, and M13 were antiproliferative at 100 µg/mL and they were further tested at lower concentrations. Fractions M12 and M13 exerted the highest growth inhibition with an IC50 of 19.5 ± 8.6 and 34.9 ± 7.3 µg/mL, respectively. Fraction M12 was further fractionated in three sub-fractions M12a, M12b, and M12c. Fraction M12a was identified as di-ethyl-hexyl-phthalate, fraction M12b as a triglyceride substituted by at least two fatty acids (predominantly oleic acid accompanied with eicosapentaenoic acid) and fraction M12c as another triglyceride substituted with eicosapentaenoic acid and saturated fatty acids. Bioactive triglyceride contained in M12c exerted the highest antiproliferative activity with an IC50 of 11.33 ± 5.6 µg/mL. Biological activity in shrimp had been previously attributed to astaxanthin; this study demonstrated that polyunsaturated fatty acids are the main compounds responsible for antiproliferative activity. 相似文献
992.
Teresa Auguet Alba Berlanga Esther Guiu-Jurado Salomé Martinez José Antonio Porras Gemma Aragonès Fátima Sabench Mercé Hernandez Carmen Aguilar Joan Josep Sirvent Daniel Del Castillo Cristóbal Richart 《International journal of molecular sciences》2014,15(12):22173-22187
Lipid accumulation in the human liver seems to be a crucial mechanism in the pathogenesis and the progression of non-alcoholic fatty liver disease (NAFLD). We aimed to evaluate gene expression of different fatty acid (FA) metabolism-related genes in morbidly obese (MO) women with NAFLD. Liver expression of key genes related to de novo FA synthesis (LXRα, SREBP1c, ACC1, FAS), FA uptake and transport (PPARγ, CD36, FABP4), FA oxidation (PPARα), and inflammation (IL6, TNFα, CRP, PPARδ) were assessed by RT-qPCR in 127 MO women with normal liver histology (NL, n = 13), simple steatosis (SS, n = 47) and non-alcoholic steatohepatitis (NASH, n = 67). Liver FAS mRNA expression was significantly higher in MO NAFLD women with both SS and NASH compared to those with NL (p = 0.003, p = 0.010, respectively). Hepatic IL6 and TNFα mRNA expression was higher in NASH than in SS subjects (p = 0.033, p = 0.050, respectively). Interestingly, LXRα, ACC1 and FAS expression had an inverse relation with the grade of steatosis. These results were confirmed by western blot analysis. In conclusion, our results indicate that lipogenesis seems to be downregulated in advanced stages of SS, suggesting that, in this type of extreme obesity, the deregulation of the lipogenic pathway might be associated with the severity of steatosis. 相似文献
993.
Roberta Barbizan Mateus V. Castro Rui Seabra Ferreira Jr. Benedito Barraviera Alexandre L. R. Oliveira 《International journal of molecular sciences》2014,15(11):19535-19551
We recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of reimplantation. Female Lewis rats (seven weeks old) were subjected to unilateral ventral root avulsion (VRA) at L4, L5 and L6 levels and divided into the following groups (n = 5 for each group): Avulsion, sealant reimplanted roots and sealant reimplanted roots plus MC. After four weeks and 12 weeks post-surgery, the lumbar intumescences were processed by transmission electron microscopy, to analyze synaptic inputs to the repaired α motoneurons. Also, the ipsi and contralateral sciatic nerves were processed for axon counting and morphometry. The ultrastructural results indicated a significant preservation of inhibitory pre-synaptic boutons in the groups repaired with sealant alone and associated with MC therapy. Moreover, the average number of axons was higher in treated groups when compared to avulsion only. Complementary to the fiber counting, the morphometric analysis of axonal diameter and “g” ratio demonstrated that root reimplantation improved the motor component recovery. In conclusion, the data herein demonstrate that root reimplantation at the lesion site may be considered a therapeutic approach, following proximal lesions in the interface of central nervous system (CNS) and peripheral nervous system (PNS), and that MC therapy does not further improve the regenerative recovery, up to 12 weeks post lesion. 相似文献
994.
Jesús Lozano-Sánchez María Castro-Puyana Jose A. Mendiola Antonio Segura-Carretero Alejandro Cifuentes Elena Ibá?ez 《International journal of molecular sciences》2014,15(9):16270-16283
The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals. 相似文献
995.
Ryan M. Williams Cassandra L. Crihfield Srikanth Gattu Lisa A. Holland Letha J. Sooter 《International journal of molecular sciences》2014,15(8):14332-14347
Widespread use of the chlorotriazine herbicide, atrazine, has led to serious environmental and human health consequences. Current methods of detecting atrazine contamination are neither rapid nor cost-effective. In this work, atrazine-specific single-stranded DNA (ssDNA) molecular recognition elements (MRE) were isolated. We utilized a stringent Systematic Evolution of Ligands by Exponential Enrichment (SELEX) methodology that placed the greatest emphasis on what the MRE should not bind to. After twelve rounds of SELEX, an atrazine-specific MRE with high affinity was obtained. The equilibrium dissociation constant (Kd) of the ssDNA sequence is 0.62 ± 0.21 nM. It also has significant selectivity for atrazine over atrazine metabolites and other pesticides found in environmentally similar locations and concentrations. Furthermore, we have detected environmentally relevant atrazine concentrations in river water using this MRE. The strong affinity and selectivity of the selected atrazine-specific ssDNA validated the stringent SELEX methodology and identified a MRE that will be useful for rapid atrazine detection in environmental samples. 相似文献
996.
Effect of green manure and supplemental fertility amendments on selected soil quality parameters in an organic potato rotation in Eastern Canada 总被引:1,自引:0,他引:1
Mehdi Sharifi Derek H. Lynch Andrew Hammermeister David L. Burton Aime J. Messiga 《Nutrient Cycling in Agroecosystems》2014,100(2):135-146
The effects of green manure, crop sequence and off-farm composts on selected soil quality parameters were assessed in a three-year organic potato (Solanum tuberosum L.) rotation in Eastern Canada. Three crop sequences varying in preceding green manure [red clover (RCl) + RCl, and beans/buckwheat or carrots + oats/peas/vetch mixture (OPV)] as main plots and four fertility treatments applied in the potato phase only [control; inorganic fertilizer; municipal solid waste compost (MSW); composted paper mill biosolid (PMB)] as subplots were compared. In 2008 and 2010, changes in selected soil quality parameters (0–15 cm) were assessed prior to planting of potatoes and at potato tuber initiation stage. Potentially mineralizable nitrogen (N) and the acid phosphatase enzyme activity average values across years were greater following RCl (1.51 abs and 622 kg ha?1) compared with OPV (1.32 abs and 414 kg ha?1) at potato planting. Soil NO3–N average value was greater following RCl compared with OPV (63 vs. 52 kg ha?1) at tuber initiation. For the other measured parameters, OPV and RCl were similar. The soil organic carbon (C) and particulate organic matter-C were greater under PMB and MSW (31.1 and 7.57 kg ha?1) compared with fertilizer treatment (27.9 and 6.05 kg ha?1). The microbial biomass C and microbial biomass quotient were greater under MSW (216 kg ha?1 and 0.73 %) than PMB and fertilizer (147 kg ha?1 and 0.50 %) across crop rotations. Annual legume green manures and off-farm composts can be used to satisfy potato N requirement and maintains soil quality in organic potato rotations. 相似文献
997.
Katelyn A. Congreves R. Paul Voroney Laura L. Van Eerd 《Nutrient Cycling in Agroecosystems》2014,100(3):257-271
After cole crop harvest, over 400 kg N ha?1 may remain in the field as crop residues and soil mineral N. Thus, methods to reduce potential post-harvest N losses are needed. Urea with 5 % 15N excess was incorporated in mini-plots to produce 15N enriched broccoli (Brassica olecerea var italica L.). The fate of above-ground crop residue-derived N (15Nresidue-above) and below-ground residual fertilizer or root biomass N (15Nresidue-below) were studied from broccoli harvest (Aug and Sept 2011) to spring wheat (Triticum durum L.) harvest (July 2012), with and without an amendment of used cooking oil. The 15Nresidue-below remained mostly as organic N, was not influenced by the amendment, and was resistant to post-harvest losses. With the oil amendment, soil mineral 15Nresidue-above was reduced by 19 kg ha?1 and microbial biomass 15Nresidue-above was increased by 21 kg ha?1 2 weeks after broccoli harvest, indicating immobilization of 15Nresidue-above and reduced potential N losses. At spring wheat harvest, amended soil had greater total, organic, and mineral 15Nresidue-above compared to the unamended control, by 44, 43, and 0.75 kg ha?1, respectively. The amendment increased the recovery of 15Nresidue-above in the soil total N pool by 209 % at spring wheat harvest, and it did not affect spring wheat yields or plant 15Nresidue-above content. It is possible that the amendment facilitated the incorporation of 15Nresidue-above into organic compounds, which were less susceptible to losses. Growers should consider applying used cooking oil at harvest to minimize potential N losses and to increase the soil organic N fraction. 相似文献
998.
Niels A. J. Cremers Ditte M. S. Lundvig Stephanie C. M. van Dalen Rik F. Schelbergen Peter L. E. M. van Lent Walter A. Szarek Raymond F. Regan Carine E. Carels Frank A. D. T. G. Wagener 《International journal of molecular sciences》2014,15(10):17974-17999
Mesenchymal stem cell (MSC) administration is a promising adjuvant therapy to treat tissue injury. However, MSC survival after administration is often hampered by oxidative stress at the site of injury. Heme oxygenase (HO) generates the cytoprotective effector molecules biliverdin/bilirubin, carbon monoxide (CO) and iron/ferritin by breaking down heme. Since HO-activity mediates anti-apoptotic, anti-inflammatory, and anti-oxidative effects, we hypothesized that modulation of the HO-system affects MSC survival. Adipose-derived MSCs (ASCs) from wild type (WT) and HO-2 knockout (KO) mice were isolated and characterized with respect to ASC marker expression. In order to analyze potential modulatory effects of the HO-system on ASC survival, WT and HO-2 KO ASCs were pre-treated with HO-activity modulators, or downstream effector molecules biliverdin, bilirubin, and CO before co-exposure of ASCs to a toxic dose of H2O2. Surprisingly, sensitivity to H2O2-mediated cell death was similar in WT and HO-2 KO ASCs. However, pre-induction of HO-1 expression using curcumin increased ASC survival after H2O2 exposure in both WT and HO-2 KO ASCs. Simultaneous inhibition of HO-activity resulted in loss of curcumin-mediated protection. Co-treatment with glutathione precursor N-Acetylcysteine promoted ASC survival. However, co-incubation with HO-effector molecules bilirubin and biliverdin did not rescue from H2O2-mediated cell death, whereas co-exposure to CO-releasing molecules-2 (CORM-2) significantly increased cell survival, independently from HO-2 expression. Summarizing, our results show that curcumin protects via an HO-1 dependent mechanism against H2O2-mediated apoptosis, and likely through the generation of CO. HO-1 pre-induction or administration of CORMs may thus form an attractive strategy to improve MSC therapy. 相似文献
999.
Marie Stiborová Eva Frei Heinz H. Schmeiser Volker M. Arlt Václav Martínek 《International journal of molecular sciences》2014,15(6):10271-10295
This review summarizes the results found in studies investigating the enzymatic activation of two genotoxic nitro-aromatics, an environmental pollutant and carcinogen 3-nitrobenzanthrone (3-NBA) and a natural plant nephrotoxin and carcinogen aristolochic acid I (AAI), to reactive species forming covalent DNA adducts. Experimental and theoretical approaches determined the reasons why human NAD(P)H:quinone oxidoreductase (NQO1) and cytochromes P450 (CYP) 1A1 and 1A2 have the potential to reductively activate both nitro-aromatics. The results also contributed to the elucidation of the molecular mechanisms of these reactions. The contribution of conjugation enzymes such as N,O-acetyltransferases (NATs) and sulfotransferases (SULTs) to the activation of 3-NBA and AAI was also examined. The results indicated differences in the abilities of 3-NBA and AAI metabolites to be further activated by these conjugation enzymes. The formation of DNA adducts generated by both carcinogens during their reductive activation by the NOQ1 and CYP1A1/2 enzymes was investigated with pure enzymes, enzymes present in subcellular cytosolic and microsomal fractions, selective inhibitors, and animal models (including knock-out and humanized animals). For the theoretical approaches, flexible in silico docking methods as well as ab initio calculations were employed. The results summarized in this review demonstrate that a combination of experimental and theoretical approaches is a useful tool to study the enzyme-mediated reaction mechanisms of 3-NBA and AAI reduction. 相似文献
1000.
Nadielly R. Andrade Silva Marcos A. C. Luna André L. C. M. A. Santiago Luciana O. Franco Grayce K. B. Silva Patrícia M. de Souza Kaoru Okada Clarissa D. C. Albuquerque Carlos A. Alves da Silva Galba M. Campos-Takaki 《International journal of molecular sciences》2014,15(9):15377-15395
A Mucoralean fungus was isolated from Caatinga soil of Pernambuco, Northeast of Brazil, and was identified as Cunninghamella echinulata by morphological, physiological, and biochemical tests. This strain was evaluated for biosurfactant/bioemulsifier production using soybean oil waste (SOW) and corn steep liquor (CSL) as substrates, added to basic saline solution, by measuring surface tension and emulsifier index and activity. The best results showed the surface water tension was reduced from 72 to 36 mN/m, and an emulsification index (E24) of 80% was obtained using engine oil and burnt engine oil, respectively. A new molecule of biosurfactant showed an anionic charge and a polymeric chemical composition consisting of lipids (40.0% w/w), carbohydrates (35.2% w/w) and protein (20.3% w/w). In addition, the biosurfactant solution (1%) demonstrated its ability for an oil displacement area (ODA) of 37.36 cm2, which is quite similar to that for Triton X-100 (38.46 cm2). The stability of the reduction in the surface water tension as well as of the emulsifier index proved to be stable over a wide range of temperatures, in pH, and in salt concentration (4%–6% w/v). The biosurfactant showed an ability to reduce and increase the viscosity of hydrophobic substrates and their molecules, suggesting that it is a suitable candidate for mediated enhanced oil recovery. At the same time, these studies indicate that renewable, relatively inexpensive and easily available resources can be used for important biotechnological processes. 相似文献