Search results for "succinic acid"
showing 10 items of 57 documents
Oxidative metabolism in a rat hepatoma (N13) and isolated rat hepatocytes: A flow cytometric comparative study
1996
Recently, we have developed a new and fast kinetic method for assessing mitochondrial membrane potential by flow cytometry, based on the quantitation of the initial rate of rhodamine 123 (Rh123) uptake by living cells. This test has proved suitable to detect metabolic and toxic effects on mitochondria. To characterize energy metabolism in a rat hepatoma cell line (N13), we applied this method to assess several metabolic pathways that eventually generate mitochondrial membrane potential. Using this approach, we found that N13 hepatoma cells retain an oxidative capacity comparable with that observed in isolated hepatocytes under the same conditions. These results show that this cell line may …
Different guidelines for imaging after first UTI in febrile infants: yield, cost, and radiation.
2013
OBJECTIVE: To evaluate the yield, economic, and radiation costs of 5 diagnostic algorithms compared with a protocol where all tests are performed (ultrasonography scan, cystography, and late technetium99dimercaptosuccinic acid scan) in children after the first febrile urinary tract infections. METHODS: A total of 304 children, 2 to 36 months of age, who completed the diagnostic follow-up (ultrasonography, cystourethrography, and acute and late technetium99dimercaptosuccinic acid scans) of a randomized controlled trial (Italian Renal Infection Study 1) were eligible. The guidelines applied to this cohort in a retrospective simulation were: Melbourne Royal Children’s Hospital, National Insti…
Commentary to 'Early clean intermittent catheterization may not prevent dimercaptosuccinic acid renal scan abnormalities in children with spinal dysr…
2013
The authors aimed to address a clinically relevant issue: do we prevent new renal scarring by early administration of clean intermittent catheterization (CIC) in patients with spina bifida? In 2006, Peter Dik and co-workers presented their results of the concept of prophylactic initiation of CIC combined with antimuscarinic therapy in myelodysplastic newborns. Out of 144 children, five patients had pre-existing renal abnormalities, 69 had an overactive sphincter, 27 had reflux, and six had renal scarring. Five of the six patients with renal scarring were put on CIC and antimuscarinic therapy several months after birth. This study provided prima facie evidence that early initiation of CIC an…
Heterogeneous photocatalytic aqueous succinic acid formation from maleic acid reduction
2022
This study reports the anaerobic reduction of maleic acid to succinic acid in aqueous dispersion of different TiO2 based photocatalysts. Some home prepared and commercial solids containing different polymorphic phases of TiO2 and loaded with Pt and Ru were compared at different acidic pHs. The aim of the work was to verify the feasibility of the process and to determine the best samples and the optimal experimental conditions of the reaction. The best selectivity towards succinic acid was 23.2 % at 70 % of maleic acid conversion. Fumaric acid was also formed as another high added value compound, and its quantity was related to the experimental conditions and the photocatalyst used.
Molecular composition and chemotaxonomic aspects of Eocene amber from the Ameki Formation, Nigeria
2012
The molecular composition of fossil resin from the Eocene Ameki Formation, southern Nigeria has been analyzed by infrared spectroscopy, pyrolysis–gas chromatography–mass spectrometry and thermochemolysis gas chromatography–mass spectrometry to determine the structural class and botanical source of the resin. The pyrolysis products were dominated by bicyclic products derived from regular labdatriene structure and lacked succinic acid indicating Class Ib type amber. The biomarker compositions in the pyrolysates are dominated by sesquiterpenoids of the cadinane and bisabolane classes that are common constituents of higher plants and labdane type diterpenoids. The exclusive presence of labdane …
Lineare polyester mit alkoholischen endgruppen und deren bestimmung
1955
Lineare Bernsteinsaure-1,6-Hexandiol-Polyester mit alkoholischen Endgruppen werden mit einem uberschus des Diols durch Schmelz- und durch Losungskondensation hergestellt. Hohermolekulare Polyester mit uberwiegend alkoholischen Endgruppen werden durch. Nachkondensation mit dem Diol erhalten. Die Umsetzung der Produkte mit Phenylisocyanat fuhrt zu Polyesterdiurethanen. Die Ermittlung des Stickstoffs nach Kjeldahl liefert mit befriedigender Genauigkeit Endgruppenmolekulargewichte bis zum Molgewicht ∼5 · 103. Bei der Totalhydrolyse der Polyesterdiurethane bildet sich Anilin, das mit einem empfindlichen, photometrischen Verfahren quantitative erfast wird. Aus der so bestimmten Anilinmenge wurden…
Partial purification and characterization of succinyl-CoA synthetase from Saccharomyces cerevisiae
1983
Succinyl-CoA synthetase from Saccharomyces cerevisiae was partially purified (20-fold) with a yield of 44%. The Michaelis-Menten constants were determined: Km (succinate) = 17 mM; Km (ATP) = 0.13 mM; Km (CoA) = 0.03 mM. The succinyl-CoA synthetase has a molecular weight of about 80000 dalton (as determined by polyacrylamide gradient gel electrophoresis). The pH optimum is at 6.0. During fermentation the activity of succinyl-CoA synthetase is lower than in aerobically grown yeast cells. The presence of succinyl-CoA synthetase in fermenting yeasts may be regarded as an indication for the oxidative formation of succinate. In fermenting yeast cells succinyl-CoA synthetase is repressed by glucos…
Escherichia coli possesses two homologous anaerobic C4-dicarboxylate membrane transporters (DcuA and DcuB) distinct from the aerobic dicarboxylate tr…
1994
The nucleotide sequences of two Escherichia coli genes, dcuA and dcuB (formerly designated genA and genF), have been shown to encode highly homologous products, M(r) 45,751 and 47,935 (434 and 446 amino acid residues) with 36% sequence identity (63% similarity). These proteins have a high proportion (approximately 61%) of hydrophobic residues and are probably members of a new group of integral inner membrane proteins. The locations of the dcu genes, one upstream of the aspartase gene (dcuA-aspA) and the other downstream of the anaerobic fumarase gene (fumB-dcuB), suggested that they may function in the anaerobic transport of C4-dicarboxylic acids. Growth tests and transport studies with mut…
Effects of combinational use of controlled atmosphere, cold storage and edible coating applications on shelf life and quality attributes of fresh-cut…
2022
Abstract Background Persimmon fruits are cherished for their unique flavor and high nutrient content. In the present study, the effects of Aloe vera-based edible coatings (EC) added with 1% ascorbic acid, 1% citric acid and 5% calcium chloride in modified atmosphere packaging (MAP) and their impact on shelf-life quality of fresh-cut persimmon fruit, were investigated. The experimental design consisted of four treatments 1) Aloe vera edible coating + modified atmosphere packaging (EC + MAP), 2) untreated fruit packaged with MAP (CTR + MAP); 3) Aloe vera-based edible coating in passive atmosphere (EC PASSIVE); 4) untreated fruit in passive atmosphere (CTR PASSIVE). Persimmon fruit were stored…
Structure, stability, and fragmentation of sodium bis(2-ethylhexyl)sulfosuccinate negatively charged aggregates in vacuo by MD simulations.
2014
Negatively charged supramolecular aggregates formed in vacuo by n bis(2-ethylhexyl)sulfosuccinate (AOT(-)) anions and n + n(c) sodium counterions (i.e., [AOT(n) Na(n+nc)](nc)) have been investigated by molecular dynamics (MD) simulations for n = 1 to 20 and n(c) = -1 to -5. By comparing the maximum excess charge values of negatively and positively charged AOTNa aggregates, it is found that the charge storage capability is higher for the latter systems, the difference decreasing as the aggregation number increases. Statistical analysis of physical properties like gyration radii and moment of inertia tensors of aggregates provides detailed information on their structural properties. Even for …