Thyroid hormone modulates the responsiveness of rat aorta to alpha1-adrenergic stimulation: an effect due to increased activation of beta2-adrenergic signaling.

Aim: The ability of the thyroid hormone to increase cardiac output and to lower systemic vascular resistance may provide a novel treatment for cardiovascular diseases. Therefore, understanding the mechanisms of thyroid hormone action on the heart and peripheral vasculature could be of clinical importance. We previously found that thyroid hormone modulates the alpha1-adrenergic effect on vascular reactivity of rat aortas.

Comparison of high-resolution magnification narrow-band imaging and white-light endoscopy in the prediction of histology in Barrett's oesophagus.

Objective: To evaluate whether there is any appreciable difference in imaging characteristics between high-resolution magnification white-light endoscopy (WLE-Z) and narrow-band imaging (NBI-Z) in Barrett's oesophagus (BE) and if this translates into superior prediction of histology.

Material And Methods: This was a prospective single-centre study involving 21 patients (75 areas, corresponding NBI-Z and WLE-Z images) with BE. Mucosal patterns (pit pattern and microvascular morphology) were evaluated for their image quality on a visual analogue scale (VAS) of 1-10 by five expert endoscopists.

Narrow-band imaging with magnification in Barrett's esophagus: validation of a simplified grading system of mucosal morphology patterns against histology.

Background And Study Aims: Validation of a simplified classification of mucosal morphology in prediction of histology in Barrett's esophagus using narrow-band imaging with magnification (NBI-Z) and assessing its reproducibility by endoscopists experienced in the use of NBI (NBI-experts) and by endoscopists who were new to NBI (non-NBI-experts).

Patients And Methods: In a prospective cohort study of 109 patients with Barrett's esophagus at a single tertiary referral center, mucosal patterns visualized in Barrett's esophagus on NBI-Z were classified into four easily distinguishable types: A, round pits with regular microvasculature; B, villous/ridge pits with regular microvasculature; C, absent pits with regular microvasculature; D, distorted pits with irregular microvasculature. The NBI-Z grading was compared with the final histopathological diagnosis, and positive (PPV) and negative predictive values (NPV) were calculated.

Decreased vascular reactivity to alpha1 adrenergic stimulation in the presence of hypothyroid state: a part of an adaptive response?

Aim: A hypothyroid state frequently accompanies cardiac illnesses but its physiological significance for the cardiovascular hemodynamics remains largely unknown. Therefore, the present study investigated possible physiological consequences on vascular function in an experimental model of low thyroid hormone state.

Methods: Hypothyroidism was induced in rats by the administration of 6-n-propyl-2-thiouracil in drinking water (final concentration of 0.

Blockade of angiotensin II type 1 receptor diminishes cardiac hypertrophy, but does not abolish thyroxin-induced preconditioning.

Growth and stress seem to share common intracellular pathways and activation of growth signaling can increase resistance to stress. Thyroid hormone induces cardiac hypertrophy and preconditions the myocardium against ischemia reperfusion injury. The present study investigated whether this response is mediated by renin-angiotensin system (RAS).