Search results for "Primer"

Following ionic activity by electrochemistry during the polymerase chain reaction

2009

The most commonly used technique for gene detection is the polymerase chain reaction (PCR). PCR is associated with alterations in ionic activity because inorganic pyrophosphate (PPi) and inorganic phosphate (Pi) ions are produced during nucleotide polymerization. To maintain electro-neutrality, magnesium, potassium, and ammonium ions are bound to DNA. Deoxynucleotides are also bound to DNA during PCR. Some authors have described DNA itself as an electrically conducting polymer formed by base stapling with the formation of extensive Pi systems. In the current study, alterations in electrical conductivity determined experimentally during PCR are reported, and a model explaining the observed c…

Mathematical problem-solving in early school years with Bee-bot

2018

Los entornos relacionados con la robótica y los lenguajes visuales de programación por bloques permiten plantear tareas que pueden ser entendidas como problemas con contenido matemático aptos para edades escolares tempranas. Estos entornos permiten proponer situaciones problemáticas en edades en las que el formalismo o el escaso conocimiento matemático impide a los estudiantes abordar problemas matemáticos más complejos. En este trabajo se da cuenta de cómo el robot programable Bee-bot constituye un dispositivo privilegiado donde poder observar cómo los estudiantes toman decisiones durante el proceso de resolución. The environments related to robotics and the visual block-based programming …

Postnatal overfeeding in rats leads to moderate overweight and to cardiometabolic and oxidative alterations in adulthood.

2011

In contrast to the masses of data on obesity, few data are available concerning the cardiometabolic and oxidative consequences of moderate overweight. The model of postnatal overfeeding (OF) induces an increase in body weight at weaning that remains during adult life. Litters of Wistar rats were either maintained at 12 pups (normal-fed group, NF), or reduced to 3 pups at birth in order to induce OF. At 6 months of age, metabolic parameters, circulating oxidative stress and aortic and coronary vasoreactivity were assessed. Cardiac susceptibility to ischemia-reperfusion injury was also evaluated ex vivo as were markers of cardiac remodeling. OF led to an increase in body weight at weaning (+5…

Differentiative pathway activated by 3-aminobenzamide, an inhibitor of PARP, in human osteosarcoma MG-63 cells

2004

AbstractThis study describes the molecular mechanism by which treatment with 3-AB, a potent inhibitor of PARP, allows human osteosarcoma MG-63 cells to restrict growth and enter differentiation. Our findings show that in MG-63 cells, aberrant gene expression keeps Rb protein constitutively inactivated through hyperphosphorylation and this promotes uncontrolled proliferation of the cells. After 3-AB-treatment, the poly(ADP-ribosyl)ation of nuclear proteins markedly decreases and this results in an increase in both the hypophosphorylated active form of Rb and pRb/E2F complexes. These effects are accompanied by G1 arrest, downregulation of gene products required for proliferation (cyclin D1, β…

Exposure to cadmium chloride influences astrocyte-elevated gene-1 (AEG-1) expression in MDA-MB231 human breast cancer cells

2011

Abstract It is known that cadmium (Cd) is able to regulate gene expression, drastically affecting the pattern of transcriptional activity and intracellular signalization in normal and pathological human cells. We have already shown that Cd exerts a cytotoxic effect on neoplastic MDA-MB231 cells from the human breast, which is characterized by the onset of a “non-classical” apoptotic kind of death, impairment of mitochondrial activity and drastic changes in gene expression pattern. In the present study, employing a combination of conventional and differential display-PCR techniques, immunocytochemical, ELISA and Western analyses, we extended the knowledge on the transcriptional modulation ex…

Growth of immobilized DNA by polymerase: bridging nanoelectrodes with individual dsDNA molecules.

2011

We present a method for controlled connection of gold electrodes with dsDNA molecules (locally on a chip) by utilizing polymerase to elongate single-stranded DNA primers attached to the electrodes. Thiol-modified oligonucleotides are directed and immobilized to nanoscale electrodes by means of dielectrophoretic trapping, and extended in a procedure mimicking PCR, finally forming a complete dsDNA molecule bridging the gap between the electrodes. The technique opens up opportunities for building from the bottom-up, for detection and sensing applications, and also for molecular electronics.

Human renal tubular epithelial cells as target cells for antibodies to proteinase 3 (c-ANCA)

1997

Rapamycin stimulates arginine influx through CAT2 transporters in human endothelial cells

2007

In endothelial cells Tumor Necrosis Factor-alpha (TNFalpha) stimulates arginine transport through the increased expression of SLC7A2/CAT2 transcripts. Here we show that also rapamycin, an inhibitor of mTOR kinase, stimulates system y(+)-mediated arginine uptake in human endothelial cells derived from either saphenous (HSVECs) or umbilical veins (HUVECs). When used together with TNFalpha, rapamycin produces an additive stimulation of arginine transport in both cell models. These effects are observed also upon incubation with AICAR, a stimulator of Adenosine-Monophosphate-dependent-Protein Kinase (AMPK) that produces a rapamycin-independent inhibition of the mTOR pathway. Rapamycin increases …

Regulation of IL-12 p40 Promoter Activity in Primary Human Monocytes: Roles of NF-κB, CCAAT/Enhancer-Binding Protein β, and PU.1 and Identification o…

2001

Abstract Appropriate regulation of IL-12 expression is critical for cell-mediated immune responses. In the present study, we have analyzed the regulation of IL-12 p40 promoter activity in primary human monocytes in vivo. Accordingly, we analyzed the p40 promoter by in vivo footprinting in resting and activated primary human blood CD14+ monocytes. Interestingly, footprints at binding sites for trans-activating proteins such as C/EBP, NF-κB, and ETS were only found upon stimulation with LPS and IFN-γ. In contrast, a footprint over a purine-rich sequence at −155, termed GA-12 (GATA sequence in the IL-12 promoter), was observed in resting, but not activated, cells. Further characterization of t…

Expression of Putative Fatty Acid Transporter Genes Are Regulated by Peroxisome Proliferator-activated Receptor α and γ Activators in a Tissue- and I…

1998

Regulation of gene expression of three putative long-chain fatty acid transport proteins, fatty acid translocase (FAT), mitochondrial aspartate aminotransferase (mAspAT), and fatty acid transport protein (FATP), by drugs that activate peroxisome proliferator-activated receptor (PPAR) alpha and gamma were studied using normal and obese mice and rat hepatoma cells. FAT mRNA was induced in liver and intestine of normal mice and in hepatoma cells to various extents only by PPARalpha-activating drugs. FATP mRNA was similarly induced in liver, but to a lesser extent in intestine. The induction time course in the liver was slower for FAT and FATP mRNA than that of an mRNA encoding a peroxisomal en…