Purificación y caracterización del virus de la fiebre aftosa obtenido por el método Frenkel

Fil: Palma, Eduardo Lucio. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

The Paired Domain-containing Factor Pax8 and the Homeodomain-containing Factor TTF-1 Directly Interact and Synergistically Activate Transcription

Pax genes encode for transcription factors essential for tissue development in many species. Pax8, the only member of the family expressed in the thyroid tissue, is involved in the morphogenesis of the gland and in the transcriptional regulation of thyroid-specific genes. TTF-1, a homeodomain-containing factor, is also expressed in the thyroid tissue and has been demonstrated to play a role in thyroid-specific gene expression. Despite the presence of Pax8 and TTF-1 also in a few other tissues, the simultaneous expression of the two transcription factors occurs only in the thyroid, supporting the idea that Pax8 and TTF-1 might cooperate to influence thyroid-specific gene expression. In this report, we describe a physical and functional interaction between these two factors. The fusion protein GST-Pax8 is able to bind TTF-1 present in thyroid or in non-thyroid cell extracts, and by using bacterial purified TTF-1 we demonstrate that the interaction is direct. By co-immunoprecipitation, we also show that the interaction between the two proteins occurs in vivo in thyroid cells. Moreover, Pax8 and TTF-1 when co-expressed in HeLa cells synergistically activate Tg gene transcription. The synergism requires the N-terminal activation domain of TTF-1, and deletions of Pax8 indicate that the C-terminal domain of the protein is involved. Our results demonstrate a functional cooperation and a physical interaction between transcription factors of the homeodomain-containing and of the paired domain-containing gene families in the regulation of tissue-specific gene expression

Progression of the Total and Individual Capsaicinoids Content in the Fruits of Three Different Cultivars of Capsicum chinense Jacq.

The evolution of individual and total capsaicinoids content in three pepper varieties of Capsicum chinense Jacq. (‘Bode’ (B), ‘Habanero’ (H), and ‘Habanero Roxo’ (Hr)) during fruit ripening was studied. The five major capsaicinoids (nordihydrocapsaicin, capsaicin, dihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin) were extracted using ultrasound-assisted extraction and the extracts were analysed by ultra-performance liquid chromatography with fluorescence detection (UHPLC-Fl). The plants were grown in a glasshouse and sampled every 7 days until over-ripening. As expected, the results indicated that the total capsaicinoids content increases during the ripening of pepper fruits. The maximum contents of capsaicinoids were reached at different fruit development stages depending on the cultivar. The ‘Habanero Roxo’ pepper presented the greatest total capsaicinoids content (3.86 mg g1 fresh weigh, F.W.), followed by the ‘Habanero’ pepper (1.33 mg g1 F.W.) and ‘Bode’ pepper (1.00 mg g1 F.W.). In all the samples, capsaicin represented more than 80% of the total capsaicinoids content. Due to the high variability observed in the evolution of capsaicinoids content over the ripening process, this work intends to contribute to the existing knowledge on this aspect in relation to the quality of peppers

Oxidized Low-Density Lipoproteins Induce Tissue Factor Expression in T-Lymphocytes via activation of Lectin-Like Oxidized Low-Density Lipoprotein Receptor-1

T-lymphocytes plays an important role in the pathophysiology of acute coronary syndromes (ACS). T-cell activation in vitro by pro-inflammatory cytokines may lead to functional Tissue Factor (TF) expression, indicating a possible contribution of immunity to thrombosis. Oxidized low-density lipoproteins (oxLDLs) are found abundantly in atherosclerotic plaques. We aimed at evaluating the effects of oxLDLs on TF expression in T-cells and the role of the lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1)

Genetic investigations on 8 patients affected by ring 20 chromosome syndrome

<p>Abstract</p> <p>Background</p> <p>Mosaic Chromosome 20 ring [r(20)] is a chromosomal disorder associated with a rare syndrome characterized by a typical seizure phenotype, a particular electroclinical pattern, cognitive impairment, behavioural problems and absence of a consistent pattern of dysmorphology. The pathogenic mechanism underlying seizures disorders in r(20) syndrome is still unknown. We performed a detailed clinical and genetic study on 8 patients with r(20) chromosome, aimed at detecting the genetic mechanism underlying r(20) syndrome.</p> <p>Methods</p> <p>We submitted 8 subjects with a previous diagnosis of ring 20 chromosome mosaicism to a clinical re-evaluation, followed by cytogenetic, FISH, array-CGH and molecular analyses. The genetic study was also extended to their available parents.</p> <p>Results</p> <p>FISH and array-CGH experiments indicate that cryptic deletions on chromosome 20 are not the cause of the r(20) chromosome associated disease. Moreover, no evidence of chromosome 20 uniparental disomy was found. Analysis of FISH signals given by variant in size alphoid tandem repeats probes on the normal chromosome 20 and the r(20) chromosome in the mosaic carriers suggests that the r(20) chromosome is the same chromosome not circularized in the "normal" cell line.</p> <p>Conclusions</p> <p>Higher percentages of r(20) chromosome cells were observed to be related with precocious age at seizure onset and with resistance to antiepileptic drug treatment. Behavioural problems also seem to be associated with higher percentages of r(20) chromosome cells. Our results suggest that an epigenetic mechanism perturbing the expression of genes close to the telomeric regions, rather than deletion of genes located at the distal 20p and/or 20q regions, may underlie the manifestation of r(20) syndrome.</p

Integrated Bayesian Approaches Shed Light on the Dissemination Routes of the Eurasian Grapevine Germplasm

The domestication and spreading of grapevine as well as the gene flow history had been described in many studies. We used a high-quality 7k SNP dataset of 1,038 Eurasian grape varieties with unique profiles to assess the population genetic diversity, structure, and relatedness, and to infer the most likely migration events. Comparisons of putative scenarios of gene flow throughout Europe from Caucasus helped to fit the more reliable migration routes around the Mediterranean Basin. Approximate Bayesian computation (ABC) approach made possible to provide a response to several questions so far remaining unsolved. Firstly, the assessment of genetic diversity and population structure within a well-covered dataset of ancient Italian varieties suggested the different histories between the Northern and Southern Italian grapevines. Moreover, Italian genotypes were shown to be distinguishable from all the other Eurasian populations for the first time. The entire Eurasian panel confirmed the east-to-west gene flow, highlighting the Greek role as a “bridge” between the Western and Eastern Eurasia. Portuguese germplasm showed a greater proximity to French varieties than the Spanish ones, thus being the main route for gene flow from Iberian Peninsula to Central Europe. Our findings reconciled genetic and archaeological data for one of the most cultivated and fascinating crops in the world

Early Prediction of Response to Tyrosine Kinase Inhibitors by Quantification of EGFR Mutations in Plasma of NSCLC Patients.

IntroductionThe potential to accurately quantify epidermal growth factor receptor (EGFR) mutations in plasma from non–small-cell lung cancer patients would enable more rapid and more frequent analyses to assess disease status; however, the utility of such analyses for clinical purposes has only recently started to explore.MethodsPlasma samples were obtained from 69 patients with EGFR-mutated tumors and 21 negative control cases. EGFR mutations in plasma were analyzed by a standardized allele-specific polymerase chain reaction (PCR) test and ultra-deep next-generation sequencing (NGS). A semiquantitative index (SQI) was derived from dilutions of known EGFR mutation copy numbers. Clinical responses were evaluated by Response Evaluation Criteria in Solid Tumors 1.1 criteria and expressed as percent tumor shrinkage.ResultsThe sensitivity and specificity of the PCR test and NGS assay in plasma versus tissue were 72% versus 100% and 74% versus 100%, respectively. Quantitative indices by the PCR test and NGS were significantly correlated (p < 0.001). EGFR testing at baseline and serially at 4 to 60 days during tyrosine kinase inhibitor therapy revealed a progressive decrease in SQI, starting from day 4, in 95% of cases. The rate of SQI decrease correlated with percent tumor shrinkage at 2 months (p < 0.0001); at 14 days, it was more than 50% in 70% of patients (rapid responders). In two patients with slow response, an early increase in the circulating levels of the T790M mutation was observed. No early T790M mutations were seen in plasma samples of rapid responders.ConclusionsQuantification of EGFR mutations from plasma with a standardized PCR test is feasible. To our knowledge, this is the first study showing a strong correlation between the EGFR SQI in the first days of treatment and clinical response with relevant implications for patient management

Investigating the Paracrine Role of Perinatal Derivatives: Human Amniotic Fluid Stem Cell-Extracellular Vesicles Show Promising Transient Potential for Cardiomyocyte Renewal

Cardiomyocyte renewal represents an unmet clinical need for cardiac regeneration. Stem cell paracrine therapy has attracted increasing attention to resurge rescue mechanisms within the heart. We previously characterized the paracrine effects that human amniotic fluid-derived stem cells (hAFSC) can exert to provide cardioprotection and enhance cardiac repair in preclinical models of myocardial ischemia and cardiotoxicity. Here, we analyze whether hAFSC secretome formulations, namely, hAFSC conditioned medium (hAFSC-CM) over extracellular vesicles (hAFSC-EVs) separated from it, can induce cardiomyocyte renewal. c-KIT+ hAFSC were obtained by leftover samples of II trimester prenatal amniocentesis (fetal hAFSC) and from clinical waste III trimester amniotic fluid during scheduled C-section procedures (perinatal hAFSC). hAFSC were primed under 1% O2 to enrich hAFSC-CM and EVs with cardioactive factors. Neonatal mouse ventricular cardiomyocytes (mNVCM) were isolated from cardiac tissue of R26pFUCCI2 mice with cell cycle fluorescent tagging by mutually exclusive nuclear signal. mNVCM were stimulated by fetal versus perinatal hAFSC-CM and hAFSC-EVs to identify the most promising formulation for in vivo assessment in a R26pFUCCI2 neonatal mouse model of myocardial infarction (MI) via intraperitoneal delivery. While the perinatal hAFSC secretome did not provide any significant cardiogenic effect, fetal hAFSC-EVs significantly sustained mNVCM transition from S to M phase by 2-fold, while triggering cytokinesis by 4.5-fold over vehicle-treated cells. Treated mNVCM showed disorganized expression of cardiac alpha-actinin, suggesting cytoskeletal re-arrangements prior to cell renewal, with a 40% significant downregulation of Cofilin-2 and a positive trend of polymerized F-Actin. Fetal hAFSC-EVs increased cardiomyocyte cell cycle progression by 1.8-fold in the 4-day-old neonatal left ventricle myocardium short term after MI; however, such effect was lost at the later stage. Fetal hAFSC-EVs were enriched with a short isoform of Agrin, a mediator of neonatal heart regeneration acting by YAP-related signaling; yet in vitro application of YAP inhibitor verteporfin partially affected EV paracrine stimulation on mNVCM. EVs secreted by developmentally juvenile fetal hAFSC can support cardiomyocyte renewal to some extension, via intercellular conveyance of candidates possibly involving Agrin in combination with other factors. These perinatal derivative promising cardiogenic effects need further investigation to define their specific mechanism of action and enhance their potential translation into therapeutic opportunity