98 research outputs found
Interaction of glutathione transferase from horse erythrocytes with 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole
7-Chloro-4-nitrobenzo-2-oxa-1,3-diazole reacts with two thiol groups of the dimeric horse erythrocyte glutathione transferase at pH 5.0, with strong inactivation reversible on dithiothreitol treatment. The inactivation kinetic follows a biphasic pattern, similar to that caused by other thiol reagents as recently reported. Both S-methylglutathione and 1-chloro-2,4-dinitrobenzene protect the enzyme from inactivation. Analysis of the reactive SH group-containing peptide gives the sequence Ala-Ser-Cys-Leu-Tyr, identical with that of the peptide that contains the reactive cysteine 47 of the human placental transferase. In the presence of glutathione, the enzyme is not inactivated by this reagent, but it catalyzes its conjugation to glutathione. At higher pH values, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole reacts with 2 tyrosines/dimer and lysines, as well as with cysteines. Reaction with lysine seems essentially without effect on activity; whether the reactive tyrosines are important for activity could not be determined using this reagent only. However, 2 tyrosines among the 4 that are nitrated by tetranitro-methane are important for activity
Active focal segmental glomerulosclerosis is associated with massive oxidation of plasma albumin
The basic mechanism for idiopathic FSGS still is obscure. Indirect evidence in humans and generation of FSGS by oxidants
in experimental models suggest a role of free radicals. In vitro studies demonstrate a main role of plasma albumin as
antioxidant, its modification representing a chemical marker of oxidative stress. With the use of complementary liquid
chromatography electron spray ionization tandem mass spectrometry (LC-ESI-MS/MS) and biochemical methods, plasma
albumin was characterized in 34 patients with FSGS; 18 had received a renal transplant, and 17 had IgM mesangial deposition.
Patients with FSGS that was in remission or without recurrence after transplantation had normal plasma albumin, and the
same occurred in patients with primary and secondary nephrites and with chronic renal failure. In contrast, patients with
active FSGS or with posttransplantation recurrence had oxidized plasma albumin. This finding was based on the characterization
of albumin Cys 34 with an mass-to-charge ratio of 511.71 in triple charge that was consistent with the formation of a
cysteic acid carrying a sulfonic group (alb-SO3-). The exact mass of albumin was increased accordingly (+48 Da) for
incorporation of three oxygen radicals. Direct titration of the free sulfhydryl group 34 of plasma albumin and electrophoretic
titration curves confirmed loss of free sulfhydryl group and formation of a fast-moving isoform in all cases with disease
activity. This is the first demonstration of in vivo plasma albumin oxidation that was obtained with an adequate structural
approach. Albumin oxidation seems to be specific for FSGS, suggesting some pathogenetic implications. Free radical
involvement in FSGS may lead to specific therapeutic interventions
The Epidemiologic Study in San Valentino
The efficacy of a 2-month treatment with oral colostrum in the prevention of flu episodes compared with antiinfluenza vaccination was evaluated. Groups included healthy subjects without prophylaxis and those receiving both vaccination and colostrum. After 3 months of follow-up, the number of days with flu was 3 times higher in the non-colostrum subjects. The colostrum group had 13 episodes versus 14 in the colostrum + vaccination group, 41 in the group without prophylaxis, and 57 in nontreated subjects. Part 2 of the study had a similar protocol with 65 very high-risk cardiovascular subjects, all of whom had prophylaxis. The incidence of complications and hospital admission was higher in the group that received only a vaccination compared with the colostrum groups. Colostrum, both in healthy subjects and high-risk cardiovascular patients, is at least 3 times more effective than vaccination to prevent flu and is very cost-effective
Corrigendum to “Circulating Cancer Stem Cell-Derived Extracellular Vesicles as a Novel Biomarker for Clinical Outcome Evaluation”
[This corrects the article DOI: 10.1155/2019/5879616.].Peer Reviewe
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Circulating Cancer Stem Cell-Derived Extracellular Vesicles as a Novel Biomarker for Clinical Outcome Evaluation.
The recent introduction of the "precision medicine" concept in oncology pushed cancer research to focus on dynamic measurable biomarkers able to predict responses to novel anticancer therapies in order to improve clinical outcomes. Recently, the involvement of extracellular vesicles (EVs) in cancer pathophysiology has been described, and given their release from all cell types under specific stimuli, EVs have also been proposed as potential biomarkers in cancer. Among the techniques used to study EVs, flow cytometry has a high clinical potential. Here, we have applied a recently developed and simplified flow cytometry method for circulating EV enumeration, subtyping, and isolation from a large cohort of metastatic and locally advanced nonhaematological cancer patients (N = 106); samples from gender- and age-matched healthy volunteers were also analysed. A large spectrum of cancer-related markers was used to analyse differences in terms of peripheral blood circulating EV phenotypes between patients and healthy volunteers, as well as their correlation to clinical outcomes. Finally, EVs from patients and controls were isolated by fluorescence-activated cell sorting, and their protein cargoes were analysed by proteomics. Results demonstrated that EV counts were significantly higher in cancer patients than in healthy volunteers, as previously reported. More interestingly, results also demonstrated that cancer patients presented higher concentrations of circulating CD31+ endothelial-derived and tumour cancer stem cell-derived CD133 + CD326- EVs, when compared to healthy volunteers. Furthermore, higher levels of CD133 + CD326- EVs showed a significant correlation with a poor overall survival. Additionally, proteomics analysis of EV cargoes demonstrated disparities in terms of protein content and function between circulating EVs in cancer patients and healthy controls. Overall, our data strongly suggest that blood circulating cancer stem cell-derived EVs may have a role as a diagnostic and prognostic biomarker in cancer
Diagnosis of a Neonatal Ophthalmic Discharge, Ophthalmia Neonatorum, in the “Molecular Age”: Investigation for a Correct Therapy
An early double case of acute Ophthalmia neonatorum in 3-day-old twins is reported. Culture of eye swabs showed a wide bacterial polymorphism, in which common bacteria, such as Klebsiella pneumoniae, Streptococcus pneumoniae, Corynebacterium ulcerans and other Enterobacteriaceae, coexisted with atypical Mycoplasmataceae and Chlamydiaceae from resident cervical-vaginal maternal microbiota. The neonates were in an apparently healthy state, but showed red eyes with abundant greenish-yellow secretion, mild chemosis and lid edema. The maternal cervical-vaginal ecosystem resulted differently positive to the same common cultivable, atypical bacteria culturally and molecularly determined. This suggested a direct maternal-foetal transmission or a further foetal contamination before birth. An extended culture analysis for common bacteria to atypical ones was decisive to describe the involvement of Mycoplasmas (M. hominis and U. urealyticum) within the scenario of the Ophthalmia neonatorum in a Caucasian couple. The introduction of a routine PCR molecular analysis for Chlamydiaceae and N. gonorrhoeae allowed to establish which of these were present at birth, and contributed to determine the correct laboratory diagnosis and to define an adequate therapeutic protocol obtaining a complete resolution after one year for culture and atypical bacteria controls. This study suggests to improve the quality of laboratory diagnosis as unavoidable support to a correct clinical diagnosis and therapy, in a standardized modality both for swabbing and scraping, to check the new-born microbial programming starting in uterus, overtaking the \u93cultural age\u94 to the \u93molecular age\u94, and to revise the WHO guidelines of \u93SAFE Strategy\u94 for trachoma eye disease, transforming it into \u93SAFES Strategy\u94 where the \u93S\u94 letter is the acronym of \u93Sexual ecosystem and behavioural valuation/education\u94
Role of tryptophan, histidine and methionine residues in the catalytic activity of mitochondrial aspartate aminotransferase from beef kidney.
The role of tryptophan, methionine, and histidine residues in mitochondrial aspartate aminotransferase from beef kidney has been established by using N-bromosuccinimide, 2-hydroxy-5-nitrobenzylbromide, and tetraiodofluoresceine as specific chemical modifiers of the amino acid residues of the enzyme. Since N-bromosuccinimide promotes extensive inactivation of the enzyme and the chemical modification of 1.65 tryptophan and 3 methionine residues per enzymes protomer, 2-hydroxy-5-nitrobenzylbromide modifies once more 1.65 tryptophan residues per enzyme protomer but induces only 10% inactivation of the enzyme. Tetraiodofluoresceine exerts a 40% inactivation of the enzyme which is due to the chemical modification of 5.8 histidine res i
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