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11.
A new purification method for cytosolic malate dehydrogenases from several sources has been developed. The procedure, employing chromatographies on 5'AMP-Sepharose, DEAE-Sephacel and Blue-Sepharose, allows for a rapid isolation of the enzyme (approximately 40 hours), in large quantities, with good yields (45-54%). The specific activity of final preparations were around 1300 I.U./mg and were judged homogeneous by polyacrylamide gradient gel and sodium dodecyl sulfate polyacrylamide gel electrophoresis, high performance size exclusion chromatography and isoelectric focusing. 相似文献
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Rosalem Gabriel Santos Las Casas Estevam Barbosa Lima Thiago Parente González-Torres Libardo Andrés 《Biomechanics and modeling in mechanobiology》2020,19(5):1537-1549
Biomechanics and Modeling in Mechanobiology - Cell migration is a process of crucial importance for the human body. It is responsible for important processes such as wound healing and tumor... 相似文献
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The succinate dehydrogenase consists of only four subunits, all nuclearly encoded, and is part of both the respiratory chain and the Krebs cycle. Mutations in the four genes encoding the subunits of the mitochondrial respiratory chain succinate dehydrogenase have been recently reported in human and shown to be associated with a wide spectrum of clinical presentations. Although a comparatively rare deficiency in human, molecularly defined succinate dehydrogenase deficiency has already been found to cause encephalomyopathy in childhood, optic atrophy or tumor in adulthood. Because none of the typical housekeeping genes encoding this respiratory chain complex is known to present tissue-specific isoforms, the tissue-specific involvement represents a quite intriguing question, which is mostly addressed in this review. A differential impairment of electron flow through the respiratory chain, handling of oxygen, and/or metabolic blockade possibly associated with defects in the different subunits that can be advocated to account for tissue-specific involvement is discussed. 相似文献
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Valentina Isetta Josep M. Montserrat Raquel Santano Alison J. Wimms Dinesh Ramanan Holger Woehrle Daniel Navajas Ramon Farré 《PloS one》2016,11(3)
Bench testing is a useful method to characterize the response of different automatic positive airway pressure (APAP) devices under well-controlled conditions. However, previous models did not consider the diversity of obstructive sleep apnea (OSA) patients’ characteristics and phenotypes. The objective of this proof-of-concept study was to design a new bench test for realistically simulating an OSA patient’s night, and to implement a one-night example of a typical female phenotype for comparing responses to several currently-available APAP devices. We developed a novel approach aimed at replicating a typical night of sleep which includes different disturbed breathing events, disease severities, sleep/wake phases, body postures and respiratory artefacts. The simulated female OSA patient example that we implemented included periods of wake, light sleep and deep sleep with positional changes and was connected to ten different APAP devices. Flow and pressure readings were recorded; each device was tested twice. The new approach for simulating female OSA patients effectively combined a wide variety of disturbed breathing patterns to mimic the response of a predefined patient type. There were marked differences in response between devices; only three were able to overcome flow limitation to normalize breathing, and only five devices were associated with a residual apnea-hypopnea index of <5/h. In conclusion, bench tests can be designed to simulate specific patient characteristics, and typical stages of sleep, body position, and wake. Each APAP device behaved differently when exposed to this controlled model of a female OSA patient, and should lead to further understanding of OSA treatment. 相似文献
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Julia I. Gavrilyuk Ulrich Wuellner Syed Salahuddin Rajib K. Goswami Subhash C. Sinha Carlos F. Barbas 《Bioorganic & medicinal chemistry letters》2009,19(14):3716-3720
Irreversible chemical programming of monoclonal aldolase antibody (mAb) 38C2 has been accomplished with β-lactam equipped mono- and bifunctional targeting modules, including a cyclic-RGD peptide linked to either the peptide (d-Lys6)-LHRH or another cyclic RGD unit and a small-molecule integrin inhibitor SCS-873 conjugated to (d-Lys6)LHRH. We also prepared monofunctional targeting modules containing either cyclic RGD or (d-Lys6)-LHRH peptides. Binding of the chemically programmed antibodies to integrin receptors α(v)β(3) and α(v)β(5) and to the luteinizing hormone releasing hormone receptor were evaluated. The bifunctional and bivalent c-RGD/LHRH and SCS-783/LHRH, the monofunctional and tetravalent c-RGD/c-RGD, and the monofunctional bivalent c-RGD chemically programmed antibodies bound specifically to the isolated integrin receptor proteins as well as to integrins expressed on human melanoma M-21 cells. c-RGD/LHRH, SCS-783/LHRH, and LHRH chemically programmed antibodies bound specifically to the LHRH receptors expressed on human ovarian cancer cells. This approach provides an efficient, versatile, and economically viable route to high-valency therapeutic antibodies that target defined combinations of specific receptors. Additionally, this approach should be applicable to chemically programmed vaccines. 相似文献
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Corine Vialas Geneviève Pratviel Jean Bernadou Bernard Meunier 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):1061-1063
Abstract Mn TMPyP in the presence of sulfite/O2 catalyses the oxidation of dG into dIz as selectively but slower and less efficiently than in the presence of KHSO5. 相似文献
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