Front Cell Dev Biol
August 2023
Bone metastasis is one of the causes that mainly decrease survival in patients with advanced breast cancer. Therefore, it is essential to find prognostic markers for the occurrence of this type of metastasis during the early stage of the disease. Currently, cancer-associated fibroblasts, which represent 80% of the fibroblasts present in the tumor microenvironment, are an interesting target for studying new biomarkers and developing alternative therapies.
View Article and Find Full Text PDFGlucosamine-6-phosphate (GlcN6P) deaminases from Escherichia coli (EcNagBI) and Shewanella denitrificans (SdNagBII) are special examples of what constitute nonhomologous isofunctional enzymes due to their convergence, not only in catalysis, but also in cooperativity and allosteric properties. Additionally, we found that the sigmoidal kinetics of SdNagBII cannot be explained by the existing models of homotropic activation. This study describes the regulatory mechanism of SdNagBII using enzyme kinetics, isothermal titration calorimetry (ITC), and X-ray crystallography.
View Article and Find Full Text PDFhas been associated with human obesity and type-2 diabetes by using a GWAS approach. GNPDA2 is an enzyme involved in the hexosamine biosynthesis pathway, which is known to be important for nutrient sensing in various organism. Its counter enzyme, GFAT, has previously been shown to be important to the development of insulin resistance in diabetes.
View Article and Find Full Text PDFPurpose: Dendritic cells (DCs) are the most potent antigen-presenting cells that play a major role in initiating the antitumor immune response in different types of cancer. However, the prognostic significance of the accumulation of these cells in human early breast tumors is not totally clear. The aim of this study is to evaluate the prognostic relevance of CD1a( +) and CD83( +) dendritic cells in early breast cancer patients.
View Article and Find Full Text PDFMultiple sclerosis (MS) is an immune-mediated central nervous system disease mostly affecting young people. Multiple sclerosis and other neurodegenerative and white matter disorders involve oligodendrocyte (OL) damage and demyelination. Therefore, elucidating the signaling pathways involved in the remyelination process through the maturation of OL progenitor cells (OPCs) may contribute to the development of new therapeutic approaches.
View Article and Find Full Text PDFUnlabelled: We have investigated the impact of growth on glucosamine (GlcN) and N-acetylglucosamine (GlcNAc) on cellular metabolism by quantifying glycolytic metabolites in Escherichia coli Growth on GlcNAc increased intracellular pools of both GlcNAc6P and GlcN6P 10- to 20-fold compared to growth on glucose. Growth on GlcN produced a 100-fold increase in GlcN6P but only a slight increase in GlcNAc6P. Changes to the amounts of downstream glycolytic intermediates were minor compared to growth on glucose.
View Article and Find Full Text PDFWe retrospectively analyzed the findings of a prospective cohort of 75 children referred for thyroid nodules between 2008 and 2013. Prevalence of papillary differentiated thyroid carcinoma was 18.7%.
View Article and Find Full Text PDFSeveral studies have confirmed that the breast tumor microenvironment drives cancer progression and metastatic development. The aim of our research was to investigate the prognostic significance of the breast tumor microenvironment in untreated early breast cancer patients. Therefore, we analyzed the association of the expression of α-SMA, FSP, CD105 and CD146 in CD34-negative spindle-shaped stromal cells, not associated with the vasculature, in primary breast tumors with classical prognostic marker levels, metastatic recurrence, local relapse, disease-free survival, metastasis-free survival and the overall survival of patients.
View Article and Find Full Text PDFThe influence, on arsenic (As) urinary metabolic profile, of the level of As exposure was evaluated on chronic-exposed inhabitants of several locations of the Chaco-Pampean Plains in Argentina. Urinary As (UAs) was quantified as a measure of the level of exposure. The metabolic profile of UAs (inorganic As, monomethylarsonic acid, and dimethylarsinic acid) was also evaluated.
View Article and Find Full Text PDFThe role of tertiary conformational changes associated to ligand binding was explored using the allosteric enzyme glucosamine-6-phosphate (GlcN6P) deaminase from Escherichia coli (EcGNPDA) as an experimental model. This is an enzyme of amino sugar catabolism that deaminates GlcN6P, giving fructose 6-phosphate and ammonia, and is allosterically activated by N-acetylglucosamine 6-phosphate (GlcNAc6P). We resorted to the nanoencapsulation of this enzyme in wet silica sol-gels for studying the role of intrasubunit local mobility in its allosteric activation under the suppression of quaternary transition.
View Article and Find Full Text PDFUnlabelled: Serial position effects are observed when a person memorises a series of words exceeding his or her attention span. Cognitively normal individuals recall words at the beginning and end of the list more frequently than those in the middle, which reflects the way that short- and long-term episodic memory works.
Objective: To study the serial position effect in patients with mild cognitive impairment (MCI) compared to subjects with Alzheimer-type dementia (AD) or normal ageing (NA).
The human genome contains two genes encoding for two isoforms of the enzyme glucosamine-6-phosphate deaminase (GNPDA, EC 3.5.99.
View Article and Find Full Text PDFLipases are useful catalysts for a wide variety of industrial purposes. Herein we report the stability and thermal dependence of the activity of wild-type Bacillus pumilus lipase (BplA) and four site-directed mutants designed to improve its thermal stability. The Gly28:Ser mutation produces a dramatic four-fold increase in its k(cat) and a remarkable increase in its stability.
View Article and Find Full Text PDFGrowth on N-acetylglucosamine (GlcNAc) produces intracellular N-acetylglucosamine-6-phosphate (GlcNAc6P), which affects the regulation of the catabolism of amino sugars in Escherichia coli in two ways. First, GlcNAc6P is the inducing signal for the NagC repressor, and thus it increases the expression of the enzymes of the nagE-nagBACD operon. Second, it is the allosteric activator of glucosamine-6P (GlcN6P) deaminase, NagB, and thus increases the catalytic capacity of this key enzyme in the metabolism of amino sugars.
View Article and Find Full Text PDFContext: Little is known about the neuroendocrine effects of androgens on the GnRH-LH unit in females.
Objective: Our objective was to evaluate androgen negative feedback on the GnRH-LH axis in eumenorrheic and polycystic ovary syndrome (PCOS) adolescents.
Design And Setting: We conducted a prospective, longitudinal, randomized, double-blind study at a pediatric endocrinology clinical research center.
Aim: To determine the association between overweight children and a) other components of the mothers' metabolic syndrome, such as body mass index (BMI), waist circumference (WC), HDL-cholesterol, triglycerides, glucose, HOMA-IR, blood pressure (BP), and age; and b) the mothers' perception of their children's overweight.
Methods: Six hundred and twenty children (297 M) aged 9 +/- 2 years and their mothers aged 37.7 +/- 7 years were examined between April and August 2006.
In the yeast Saccharomyces cerevisiae, the first committed step of the lysine biosynthetic pathway is catalysed by two homocitrate synthases encoded by LYS20 and LYS21. We undertook a study of the duplicate homocitrate synthases to analyse whether their retention and presumable specialization have affected the efficiency of lysine biosynthesis in yeast. Our results show that during growth on ethanol, homocitrate is mainly synthesized through Lys21p, while under fermentative metabolism, Lys20p and Lys21p play redundant roles.
View Article and Find Full Text PDFA study was carried out to investigate accelerated forgetting of new verbal and visual material in participants complaining of memory loss, individuals with Mild Cognitive Impairment(MCI) and controls. All groups were evaluated with a standard neuropsychological battery and two tests of delayed recall 6 weeks apart for the experimental tasks.Individuals with memory complaints,but not MCI, performed normally compared to controls on immediate and 30 minute recall,but showed a striking impairment in verbal and visual memory after 6 weeks.
View Article and Find Full Text PDFLactic acid bacteria are the most adequate microorganisms for natural preservation of food. In the present work, the strain of Enterococcus faecalis CECT7121 was employed in the manufacture of craft dry-fermented sausages and its performance as a biopreservative was analysed. This strain is devoid of the genes for haemolysin and gelatinase and does not produce biogenic amines.
View Article and Find Full Text PDFCognitive function and diffusion tensor imaging were assessed in a group of 12 patients with early relapsing-remitting multiple sclerosis (disease duration
Arch Pediatr Adolesc Med
December 2007
Objective: To determine the association between metabolic syndrome (MS) components in 620 children and their mothers.
Design: Cross-sectional assessment.
Setting: Three public elementary schools in Buenos Aires, Argentina.
Objective: The metabolic syndrome is associated with insulin resistance in adults. We defined pediatric metabolic syndrome using criteria analogous to Adult Treatment Panel III. The purpose of this study was to determine whether these criteria are reliable for insulin resistance in children.
View Article and Find Full Text PDFAim: To determine prevalence of H pylori infection in symptomatic children in Buenos Aires, Argentina, and to investigate factors associated with H pylori positivity.
Methods: A total of 395 children with upper gastrointestinal symptoms referred to the Gastroenterology Unit of the Children Hospital "Sor Maria Ludovica" were evaluated for the presence of H pylori by the (13)C-Urea Breath Test ((13)C-UBT). A questionnaire was applied to the recruited population.
Objective: Current recommendations for treatment of Helicobacter pylori infection include a proton pump inhibitor in combination with two antibiotics. We evaluated the potential activity of a probiotic food as an adjuvant to antibiotic triple therapy for eradication of H. pylori infection in children from Buenos Aires, Argentina.
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