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81.
Grabeklis Andrey R. Skalny Anatoly V. Skalnaya Anastasia A. Zhegalova Irina V. Notova Svetlana V. Mazaletskaya Anna L. Skalnaya Margarita G. Tinkov Alexey A. 《Biological trace element research》2019,187(1):230-242
Biological Trace Element Research - Chronic exposure to lead causes disruption to energy production mechanisms and tissue damage, in particular through its binding to thiol groups and competition... 相似文献
82.
Summary The effects of a number of organic compounds on the germination of spores of Agaricus bisporus (J. Lange) Pilat has been investigated and a preliminary analysis of spore lipids carried out. Germination was stimulated by isocaproic acid but not by straight-chain C5 to C11 fatty acids or by the amino acids leucine and iso-leucine. Cholesterol at a concentration of 1 ppm was inhibitory. The lipid reserve of the spore comprised mono-, di- and tri-glycerides, free fatty acids and sterols. The phospholipid fraction was unusually small and contained a lecithin and cephalin fraction, phosphatidylinositol and cardiolipin phosphatidic acid; phosphatidylcholine being the most prominent component. The role of lipids and various germination stimulants in the physiology of A. bisporus spores is discussed. 相似文献
83.
James Mallet Margarita Beltrán Walter Neukirchen Mauricio Linares 《BMC evolutionary biology》2007,7(1):28
Background
To understand speciation and the maintenance of taxa as separate entities, we need information about natural hybridization and gene flow among species. 相似文献84.
Mulet M Gomila M Lemaitre B Lalucat J García-Valdés E 《Systematic and applied microbiology》2012,35(3):145-149
An entomopathogenic, Gram-negative bacterium isolated from a female specimen of the fruit fly Drosophila melanogaster was taxonomically characterised. Strain L48(T) was strictly aerobic, non-fermentative, oxidase and catalase positive, rod-shaped, and motile due to a polar inserted flagellum. Phylogenetic analysis of the 16S rRNA gene and three other housekeeping genes placed strain L48 (T) in the Pseudomonas putida phylogenetic group. DNA-DNA hybridisation studies together with phenotypic metabolic tests and MALDI-TOF MS analysis justified the proposal of strain L48(T) as a representative of a novel species, for which the name Pseudomonas entomophila sp. nov. is proposed. The type strain is deposited in culture collections under accession numbers CCUG 61470(T) and CECT 7985(T). 相似文献
85.
Fernando Marqu��s-Garc��a Nuria Ferrandiz Rosal��a Fern��ndez-Alonso Laura Gonz��lez-Cano Marta Herreros-Villanueva Manuel Rosa-Garrido Bel��n Fern��ndez-Garc��a Jos�� P. Vaque Margarita M. Marqu��s Mar��a Eugenia Alonso Jos�� Carlos Segovia Javier Le��n Mar��a C. Mar��n 《The Journal of biological chemistry》2009,284(32):21139-21156
86.
Margarita Tenopoulou Jie Chen Jean Bastin Michael J. Bennett Harry Ischiropoulos Paschalis-Thomas Doulias 《The Journal of biological chemistry》2015,290(16):10486-10494
Very long acyl-CoA dehydrogenase (VLCAD) deficiency is a genetic pediatric disorder presenting with a spectrum of phenotypes that remains for the most part untreatable. Here, we present a novel strategy for the correction of VLCAD deficiency by increasing mutant VLCAD enzymatic activity. Treatment of VLCAD-deficient fibroblasts, which express distinct mutant VLCAD protein and exhibit deficient fatty acid β-oxidation, with S-nitroso-N-acetylcysteine induced site-specific S-nitrosylation of VLCAD mutants at cysteine residue 237. Cysteine 237 S-nitrosylation was associated with an 8–17-fold increase in VLCAD-specific activity and concomitant correction of acylcarnitine profile and β-oxidation capacity, two hallmarks of the disorder. Overall, this study provides biochemical evidence for a potential therapeutic modality to correct β-oxidation deficiencies. 相似文献
87.
Domingo Hernández Javier Tri?anes Eduardo Salido Sergio Pitti Margarita Rufino José Manuel González-Posada Armando Torres 《PloS one》2015,10(6)
Background
Kidney transplant recipients have high cardiovascular risk, and vascular inflammation may play an important role. We explored whether the inflammatory state in the vessel wall was related to carotid intima-media thickness (c-IMT) and patient survival following kidney transplantation.Methods
In this prospective observational cohort study we measured c-IMT and expression of proinflammatory cytokines and adhesion molecules in the inferior epigastric artery in 115 kidney transplant candidates. Another c-IMT measurement was done 1-year post-transplantation in 107. By stepwise multiple regression analysis we explored factors associated with baseline c-IMT and their changes over time. Multivariate Cox regression analysis was constructed to identify risk factors for mortality.Results
A worse cardiovascular profile (older age, smoker, diabetic, carotid plaque, systolic blood pressure and vascular calcification) and higher VCAM-1 levels were found in patients in the highest baseline c-IMT tertile, who also had a worse survival. Factors independently related to baseline c-IMT were age (β=0.369, P<0.0001), fasting glucose (β=0.168, P=0.045), smoking (β=0.228, P=0.003) and VCAM-1 levels (β=0.244, P=0.002). Independent factors associated with c-IMT measurement 1-year post-transplantation were baseline c-IMT (β=-0.677, P<0.0001), post-transplant diabetes (β=0.225, P=0.003) and triglycerides (β=0.302, P=0.023). Vascular VCAM-1 levels were associated with increased risk of mortality in bivariate and multivariate Cox regression. Notably, nearly 50% of patients showed an increase or maintenance of high c-IMT 1 year post-transplantation and these patients experienced a higher mortality (13 versus 3.5%; P=0.021).Conclusion
A worse cardiovascular profile and a higher vascular VCAM-1 protein levels at time of KT are related to subclinical atheromatosis. This could lead to a higher post-transplant mortality. Pre-transplant c IMT, post-transplant diabetes and triglycerides at 1-year post-transplantation may condition a high c-IMT measurement post-transplantation, which may decrease patient survival. 相似文献88.
Carolina I. Cura Tomas Duffy Raúl H. Lucero Margarita Bisio Julie Péneau Matilde Jimenez-Coello Eva Calabuig María J. Gimenez Edward Valencia Ayala Sonia A. Kjos José Santalla Susan M. Mahaney Nelly M. Cayo Claudia Nagel Laura Barcán Edith S. Málaga Machaca Karla Y. Acosta Viana Laurent Brutus Susana B. Ocampo Christine Aznar Cesar A. Cuba Cuba Ricardo E. Gürtler Janine M. Ramsey Isabela Ribeiro John L. VandeBerg Zaida E. Yadon Antonio Osuna Alejandro G. Schijman 《PLoS neglected tropical diseases》2015,9(5)
Background
Trypanosoma cruzi has been classified into six Discrete Typing Units (DTUs), designated as TcI–TcVI. In order to effectively use this standardized nomenclature, a reproducible genotyping strategy is imperative. Several typing schemes have been developed with variable levels of complexity, selectivity and analytical sensitivity. Most of them can be only applied to cultured stocks. In this context, we aimed to develop a multiplex Real-Time PCR method to identify the six T. cruzi DTUs using TaqMan probes (MTq-PCR).Methods/Principal Findings
The MTq-PCR has been evaluated in 39 cultured stocks and 307 biological samples from vectors, reservoirs and patients from different geographical regions and transmission cycles in comparison with a multi-locus conventional PCR algorithm. The MTq-PCR was inclusive for laboratory stocks and natural isolates and sensitive for direct typing of different biological samples from vectors, reservoirs and patients with acute, congenital infection or Chagas reactivation. The first round SL-IR MTq-PCR detected 1 fg DNA/reaction tube of TcI, TcII and TcIII and 1 pg DNA/reaction tube of TcIV, TcV and TcVI reference strains. The MTq-PCR was able to characterize DTUs in 83% of triatomine and 96% of reservoir samples that had been typed by conventional PCR methods. Regarding clinical samples, 100% of those derived from acute infected patients, 62.5% from congenitally infected children and 50% from patients with clinical reactivation could be genotyped. Sensitivity for direct typing of blood samples from chronic Chagas disease patients (32.8% from asymptomatic and 22.2% from symptomatic patients) and mixed infections was lower than that of the conventional PCR algorithm.Conclusions/Significance
Typing is resolved after a single or a second round of Real-Time PCR, depending on the DTU. This format reduces carryover contamination and is amenable to quantification, automation and kit production. 相似文献89.
90.
Borges R Pereda D Beltrán B Prunell M Rodríguez M Machado JD 《Cellular and molecular neurobiology》2010,30(8):1359-1364
Chromaffin granules are similar organelles to the large dense core vesicles (LDCV) present in many secretory cell types including
neurons. LDCV accumulate solutes at high concentrations (catecholamines, 0.5–1 M; ATP, 120–300 mM; or Ca2+, 40 mM (Bulenda and Gratzl Biochemistry 24:7760–7765, 1985). Solutes seem to aggregate to a condensed matrix to elude osmotic lysis. The affinity of solutes for LDCV matrix is responsible
for the delayed release of catecholamines during exocytosis. The aggregation of solutes occurs due to a specific H+ pump denominated V-ATPase that maintains an inner acidic media (pH ≈5.5). This pH gradient against cytosol is also responsible
for the vesicular accumulation of amines and Ca2+. When this gradient is reduced by modulation of the V-ATPase activity, catecholamines and Ca2+ are moved toward the cytosol. In addition, some drugs largely accumulate inside LDCV and not only impair the accumulation
of natural solutes, but also act as false neurotransmitters when they are co-released with catecholamines. There is much experimental
evidence to conclude that the physiological modulation of vesicle pH and the manipulation of intravesicular media with drugs
affect the LDCV cargo and change the kinetics of exocytosis. Here, we will present some experimental data demonstrating the
participation of drugs in the kinetics of exocytosis through changes in the composition of vesicular media. We also offer
a model to explain the regulation of exocytosis by the intravesicular media that conciliate the experimentally obtained data. 相似文献