The Experts below are selected from a list of 92571 Experts worldwide ranked by ideXlab platform
Erich Gnaiger - One of the best experts on this subject based on the ideXlab platform.
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mitochondrial respiratory control and early defects of oxidative phosphorylation in the failing human heart
The International Journal of Biochemistry & Cell Biology, 2011Co-Authors: Helene Lemieux, Severin Semsroth, H Antretter, Daniel Hofer, Erich GnaigerAbstract:Abstract Heart failure is a consequence of progressive deterioration of cardiac performance. Little is known about the role of impaired oxidative phosphorylation in the progression of the disease, since previous studies of mitochondrial injuries are restricted to end-stage chronic heart failure. The present study aimed at evaluating the involvement of mitochondrial dysfunction in the development of human heart failure. We measured the control of oxidative phosphorylation with high-resolution respirometry in permeabilized myocardial fibres from donor hearts (controls), and patients with no or mild heart failure but presenting with heart disease, or chronic heart failure due to dilated or ischemic cardiomyopathy. The capacity of the phosphorylation system exerted a strong limitation on oxidative phosphorylation in the human heart, estimated at 121 pmol O2 s−1 mg−1 in the healthy left ventricle. In heart disease, a specific defect of the phosphorylation system, Complex I-linked respiration, and mass-specific fatty acid oxidation were identified. These early defects were also significant in chronic heart failure, where the capacities of the oxidative phosphorylation and electron transfer systems per cardiac tissue mass were decreased with all Tested Substrate combinations, suggesting a decline of mitochondrial density. Oxidative phosphorylation and electron transfer system capacities were higher in ventricles compared to atria, but the impaired mitochondrial quality was identical in the four cardiac chambers of chronic heart failure patients. Coupling was preserved in heart disease and chronic heart failure, in contrast to the mitochondrial dysfunction observed after prolonged cold storage of cardiac tissue. Mitochondrial defects in the phosphorylation system, Complex I respiration and mass-specific fatty acid oxidation occurred early in the development of heart failure. Targeting these mitochondrial injuries with metabolic therapy may offer a promising approach to delay the progression of heart disease.
Surindra Suthar - One of the best experts on this subject based on the ideXlab platform.
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effect of thermal pre treatment on co digestion of duckweed lemna gibba and waste activated sludge on biogas production
Chemosphere, 2017Co-Authors: Rubia Zahid Gaur, Abid Ali Khan, Surindra SutharAbstract:Abstract The duckweeds (DW) are considered as a major problem in tropical aquatic system as they grow very fast and produce enormous rich-biomass, which can be harvested for renewable energy operations. But complex lignocellulosic compounds limit their utility in process like anaerobic digestion. This batch study aimed to analyse characteristics (proximate, ultimate and physico-chemical) and possible utility of DW for anaerobic co-digestion with waste activated sludge (WAS) under mesophilic conditions for 35 d. Two sets of experiment were Tested: Substrate with and without thermal pre-treatment. Five combinations of DW: WAS (70:20, 60:20, 50:20, 40:20 and 30:20%) were established and biomethanation along with changes in pH, volatile solids (VS), volatile fatty acids (VFAs), and soluble chemical oxygen demand (sCOD) of digestate were recorded. The total CH4 yield (mL CH4 g−1 VS) ranged between 60 and 468 for pre-treated, and 9 and 76 for non-pre-treated. The maximum CH4 yield was 468 mL CH4g−1 VS in DW: WAS (50:20). Thermally treated setups, showed about 13-, 24.1-, 21.1-, 1.4-, and 2.3-fold higher CH4 than non-treated setups. The treated mixtures showed high reduction of SCOD (>41–96) and VS (>59–98%) in co-digesters. The high degree of Gompertz curve fitting (R2 > 0.99) has suggested pre-treatment of Substrate for optimal outputs of co-digester. Based on results obtained, it is suggested that DW (50–60% in digester) can be used as renewable energy resource for biomethanation process after thermal pre-treatment.
Isabel C F R Ferreira - One of the best experts on this subject based on the ideXlab platform.
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cotton and cardoon byproducts as potential growing media components for cichorium spinosum l commercial cultivation
Journal of Cleaner Production, 2019Co-Authors: Spyridon A Petropoulos, ângela Fernandes, Dejan Stojkovic, Carla Pereira, Oludemi Taofiq, Francesco Di Gioia, Nikos Tzortzakis, Marina Sokovic, Lillian Barros, Isabel C F R FerreiraAbstract:Abstract The intensification of horticultural crops cultivation makes urgent the seeking for alternative growth Substrates that could substitute non-renewable and/or synthetic growing media, such as peat and rock wool. The aim of the present study was to evaluate the potential use of byproducts from two industrial crops commonly cultivated in the Mediterranean basin, namely cardoon and cotton, as growth Substrates for Cichorium spinosum, while zeolite addition was also Tested as a soil amendment. A pot experiment was carried for two consecutive growing periods and plant growth was evaluated for six growing media compositions, while plant extracts were also evaluated in terms of their phenolic compounds profile, antioxidant and antimicrobial activities. The results of this study showed that cotton byproducts and zeolite may partially substitute peat in growth Substrate of C. spinosum and high yields comparable to peat may be achieved. Phenolic compounds content and antioxidant activity of leaves' extracts was higher for plants grown in soil which showed severe stress symptoms comparing to the other Tested Substrate blends. Antimicrobial activity was also affected by growth Substrate composition, only in the case of antibacterial properties of leaves' extracts, whereas none of the extracts presented significant antifungal activities. In conclusion, the use of cotton ginning byproducts and zeolite in growth Substrate blends may partially substitute conventional Substrates as peat in horticultural crops production, resulting in reduction of production cost and lessening of bulky byproducts’ management and related environmental burden without compromising yield.
Irini Angelidaki - One of the best experts on this subject based on the ideXlab platform.
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thermophilic fermentative hydrogen production by the newly isolated thermoanaerobacterium thermosaccharolyticum psu 2
International Journal of Hydrogen Energy, 2008Co-Authors: Sompong Othong, P Prasertsan, Dimitar Borisov Karakashev, Irini AngelidakiAbstract:Abstract A thermophilic H 2 -producing bacterial strain was isolated from a biohydrogen reactor fed with palm oil mill effluent (POME) and identified as Thermoanaerobacterium thermosaccharolyticum using 16S rRNA gene analysis. The isolated bacterium, designated as T. thermosaccharolyticum PSU-2, showed a high yield and production rate of H 2 . Temperature optimum, pH optimum and Substrate utilization for H 2 production were investigated in batch conditions. All of Tested Substrate was utilized for H 2 production, while sucrose, xylose and starch were the preferred Substrates. The strain produced H 2 within a wide range of pH (4.5–8) and temperature (45– 70 ∘ C ), with the optimal temperature 60 ∘ C and optimal initial pH about 6.25. Maximum of H 2 production rate was registered from hour 8 to hour 16 in late exponential phase. The H 2 production was drastically reduced in a prolonged fermentation (24 h) and stopped at pH 4.5 due to the accumulation of organic acids. The maximum H 2 production yield and rate at sucrose concentration of 20 g l - 1 , pH 6.25 and temperature 60 ∘ C were 2.53 mol H 2 mol - 1 hexose and 12.12 mmol H 2 l - 1 h - 1 , respectively. Organic nitrogen amended medium improved the H 2 production with 68% compared to inorganic nitrogen amended medium. The strain performed ethanol–acetate type fermentation in inorganic nitrogen amended medium, while it performed butyrate–acetate type fermentation in organic nitrogen amended medium.
Helene Lemieux - One of the best experts on this subject based on the ideXlab platform.
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mitochondrial respiratory control and early defects of oxidative phosphorylation in the failing human heart
The International Journal of Biochemistry & Cell Biology, 2011Co-Authors: Helene Lemieux, Severin Semsroth, H Antretter, Daniel Hofer, Erich GnaigerAbstract:Abstract Heart failure is a consequence of progressive deterioration of cardiac performance. Little is known about the role of impaired oxidative phosphorylation in the progression of the disease, since previous studies of mitochondrial injuries are restricted to end-stage chronic heart failure. The present study aimed at evaluating the involvement of mitochondrial dysfunction in the development of human heart failure. We measured the control of oxidative phosphorylation with high-resolution respirometry in permeabilized myocardial fibres from donor hearts (controls), and patients with no or mild heart failure but presenting with heart disease, or chronic heart failure due to dilated or ischemic cardiomyopathy. The capacity of the phosphorylation system exerted a strong limitation on oxidative phosphorylation in the human heart, estimated at 121 pmol O2 s−1 mg−1 in the healthy left ventricle. In heart disease, a specific defect of the phosphorylation system, Complex I-linked respiration, and mass-specific fatty acid oxidation were identified. These early defects were also significant in chronic heart failure, where the capacities of the oxidative phosphorylation and electron transfer systems per cardiac tissue mass were decreased with all Tested Substrate combinations, suggesting a decline of mitochondrial density. Oxidative phosphorylation and electron transfer system capacities were higher in ventricles compared to atria, but the impaired mitochondrial quality was identical in the four cardiac chambers of chronic heart failure patients. Coupling was preserved in heart disease and chronic heart failure, in contrast to the mitochondrial dysfunction observed after prolonged cold storage of cardiac tissue. Mitochondrial defects in the phosphorylation system, Complex I respiration and mass-specific fatty acid oxidation occurred early in the development of heart failure. Targeting these mitochondrial injuries with metabolic therapy may offer a promising approach to delay the progression of heart disease.