Caffeine (CAF) levels in instant regular coffees, instant decaffeinated coffees, and instant teas are determined and compared using spectrophotometric and gas chromatographic methods of determination. Modification of a previously reported spectrophotometric assay for CAF in biological fluids is necessary to reduce interference from theophylline (THP) and theobromine (THB). Readjustment of the b...

Cancer-associated fibroblasts (CAF) play a crucial role in regulating cancer progression, yet the molecular determinant that governs the tumor regulatory role of CAF remains unknown. Using a mouse melanoma model in which exogenous melanoma cells were grafted on the skin of two lines of mice where the genetic activation or inactivation of Notch1 signaling specifically occurs in natural host stro...

Alternative assessment approaches and, among them, self-assessment and peer-assessment are becoming increasingly important in educational contexts. Designed to compare self-assessment, peer-assessment, and teacher-assessment, this study included 90 EFL students from 3 intact classes divided into 3 groups: self-assessment, peer-assessment, and teacher-assessment. After taking the TOEFL Proficien...

background alzheimer's disease (ad) is the most common type of dementia. patients with ad have impaired semantic knowledge of nouns and verbs as well as the ability to verb retrieval. objectives the aim of this study was to compare verbal fluency and verb fluency and to investigate the association between severity and types of fluency (verbal-verb) in patients with ad. patients and methods this...

Sarcopenia is a recently defined medical condition described as age-associated loss of skeletal muscle mass and function. Recently, a transgenic mouse model was described linking dispersal of the neuromuscular junction caused by elevated agrin degradation to the rapid onset of sarcopenia. These mice show a significant elevation of serum levels of a C-terminal agrin fragment (CAF) compared to wi...

Purpose: Cancer-associated fibroblasts (CAF) actively participate in reciprocal communication with tumor cells and with other cell types in the microenvironment, contributing to a tumor-permissive neighborhood and promoting tumor progression. The aim of this study is the characterization of how CAFs from primary human colon tumors promote migration of colon cancer cells. Experimental design: Pr...

OBJECTIVES The aim of the study was to analyze the electrophysiologic characteristics of paroxysmal (PAF) and chronic (CAF) atrial fibrillation (AF) in the human right atrium (RA). BACKGROUND Differences that exist between PAF and CAF and the mechanisms of self-sustenance of these arrhythmias are incompletely understood. METHODS A total of 53 patients with PAF (25 patients, mean age 59 +/- ...

UNLABELLED Tumor cells lacking the functional p53 suppressor gene may arrest at the G2 phase of the cell cycle after exposure to ionizing radiation, resulting in increased radioresistance. Methylxanthines (MTXs), such as pentoxifylline (PTX) or caffeine (CAF), can inhibit the G2-phase checkpoint arrest of damaged cells and thus radiosensitize them. However, the effect of MTX in cells irradiated...

OBJECTIVES The purpose of this study was to compare the voltage-dependent K(+) currents of human cells of the right and left atria and determine whether electrical remodeling produced by chronic atrial fibrillation (CAF) is chamber-specific. BACKGROUND Several data point to the existence of interatrial differences in the repolarizing currents. Therefore, it could be possible that CAF-induced ...

This study evaluated the effects of ingesting sodium bicarbonate (NaHCO3) or caffeine individually or in combination on high-intensity cycling capacity. In a counterbalanced, crossover design, 13 healthy, noncycling trained males (age: 21 ± 3 years, height: 178 ± 6 cm, body mass: 76 ± 12 kg, peak power output (Wpeak): 230 ± 34 W, peak oxygen uptake: 46 ± 8 mL·kg(-1)·min(-1)) performed a graded ...