Search results for "Pathogen"
showing 10 items of 1657 documents
The Role of Endothelium in COVID-19
2021
The 2019 novel coronavirus, known as severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) or coronavirus disease 2019 (COVID-19), is causing a global pandemic. The virus primarily affects the upper and lower respiratory tracts and raises the risk of a variety of non-pulmonary consequences, the most severe and possibly fatal of which are cardiovascular problems. Data show that almost one-third of the patients with a moderate or severe form of COVID-19 had preexisting cardiovascular comorbidities such as diabetes mellitus, obesity, hypertension, heart failure, or coronary artery disease. SARS-CoV2 causes hyper inflammation, hypoxia, apoptosis, and a renin–angiotensin system imbalance …
Sjøgren's syndrome-associated oxidative stress and mitochondrial dysfunction: Prospects for chemoprevention trials
2012
An involvement of oxidative stress (OS) was found in recent studies of Sjøgren's syndrome (SS) that reported significant changes in protein oxidation, myeloperoxidase activity, TNF-α, nitrotyrosine, and GSH levels in plasma from SS patients. Excess levels of OS markers, as oxidative DNA damage and propanoyl-lysine, were reported in saliva from SS patients. Previous reports concurred with a role of OS in SS pathogenesis, by showing a decreased expression of antioxidant activities in conjunctival epithelial cells of SS patients and in parotid gland tissue samples from SS patients. A link between OS and mitochondrial dysfunction (MDF) is recognized both on the grounds of the established role o…
Chemically induced mouse models of colitis.
2012
Crohn's disease (CD) and ulcerative colitis (UC), both of which are referred to as inflammatory bowel disease (IBD), are chronic inflammatory disorders of the gastrointestinal tract that have characteristic clinical, pathological, endoscopic, and radiologic features. Knowledge about the pathogenesis of IBD has dramatically increased in recent years based in part on the use of experimental models of IBD. Although none of these models exactly mimics the human disorder, they have proven to be useful for studying many important aspects of these conditions. Detailed in this unit is a description of the most commonly used chemically induced mouse models of IBD. These include trinitrobenzene sulfo…
Glycolysis Metabolites and Risk of Atrial Fibrillation and Heart Failure in the PREDIMED Trial
2021
The increased prevalence of atrial fibrillation (AF) and heart failure (HF) highlights the need to better understand the mechanisms underlying these cardiovascular diseases (CVDs). In the present study, we aimed to evaluate the association between glycolysis-related metabolites and the risk of AF and HF in a Mediterranean population at high risk of CVD. We used two case-control studies nested within the PREDIMED trial. A total of 512 incident AF cases matched to 734 controls, and 334 incident HF cases matched to 508 controls, were included. Plasma metabolites were quantified by using hydrophilic interaction liquid chromatography coupled with high-resolution negative ion mode MS detection. C…
Pathophysiology, diagnosis and prognostic implications of endothelial dysfunction
2008
Endothelial dysfunction (ED) in the setting of cardiovascular risk factors such as hypercholesterolemia, hypertension, diabetes mellitus, chronic smoking as well as in patients with heart failure has been shown to be at least in part dependent on the production of reactive oxygen species (ROS) such as superoxide and the subsequent decrease in vascular bioavailability of nitric oxide (NO). Methods to quantify endothelial dysfunction include forearm plethysmography, flow-dependent dilation of the brachial artery, finger-pulse plethysmography, pulse curve analysis, and quantitative coronary angiography after intracoronary administration of the endothelium-dependent vasodilator acetylcholine. S…
Potential involvement of fas and its ligand in the pathogenesis of Hashimoto's thyroiditis
1997
The mechanisms responsible for thyrocyte destruction in Hashimoto's thyroiditis (HT) are poorly understood. Thyrocytes from HT glands, but not from nonautoimmune thyroids, expressed Fas. Interleukin-1β (IL-1β), abundantly produced in HT glands, induced Fas expression in normal thyrocytes, and cross-linking of Fas resulted in massive thyrocyte apoptosis. The ligand for Fas (FasL) was shown to be constitutively expressed both in normal and HT thyrocytes and was able to kill Fas-sensitive targets. Exposure to IL-1β induced thyrocyte apoptosis, which was prevented by antibodies that block Fas, suggesting that IL-1β-induced Fas expression serves as a limiting factor for thyrocyte destruction. Th…
Histometric investigations of placental villi in cases of unexpected fetal acidosis.
1994
It is not unusual that, after an apparently uneventful pregnancy and birth, postpartal analysis of fetal blood unexpectedly reveals the presence of peripartal acidosis, a finding that is inexplicable on the basis of routine observation of the placenta. Using computer-assisted histometric procedures, it is possible to make a quantitative assessment with respect to the maturity and differentiation of villi, thus casting light on the functional anatomy of these structures. 89 single-birth pregnancies were grouped in accordance to the pH of blood in the umbilical artery (pre-acidosis, acidosis, non acidotic). In acidotic newborns, there is an absolute reduction in the surface area of the placen…
Helicobacter pyloriand Non-malignant Diseases
2008
In 2007 Helicobacter pylori research continued to deal with some controversies raised in the last decade. The main problems remain unsolved: peptic ulcer disease negative for H. pylori, synergism of H. pylori infection and aspirin and other nonsteroidal anti-inflammatory drugs or cyclooxygenase 2 specific inhibitors, the role of H. pylori eradication in uninvestigated and nonulcer dyspepsia, and the possible protective effect of H. pylori infection against gastroesophageal reflux disease and its complications such as Barrett's esophagus and adenocarcinoma. The incidence and prevalence of peptic ulcer disease as well as ulcer-related mortality are continuing to decline all over the world. Th…
Distinct subsets of regulatory T cells during pregnancy: is the imbalance of these subsets involved in the pathogenesis of preeclampsia?
2008
Abstract Regulatory T cells (CD4 + CD25 + FoxP3 + -Treg cells) are important regulators of tolerance induction during pregnancy. We now found that the number of CD4 + CD25 + FoxP3 + -Treg cells decreases during normal course of pregnancy and even more so in women affected by preeclampsia. The functional activity of these CD4 + CD25 + -Treg cells was significantly reduced in comparison to those of healthy pregnants. Further analysis revealed two Treg subsets that differed with regard to the FoxP3 and CD25 expression. The percentage of both, CD4 + CD25 + FoxP3 high+ -Treg and CD4 + CD25 high+ FoxP3 + , was maximal in the first and second trimenon, but declined severely in the third trimenon. …
Wastewater-based epidemiology, a tool to bridge biomarkers of exposure, contaminants, and human health
2021
The concept of wastewater-based epidemiology also known as sewage epidemiology was proposed by Daughton in 2001. Wastewater-based epidemiology has become now a reality that makes it possible to determine consumption or exposure to chemical substances or pathogens in a population by measuring certain compounds (drugs of abuse, metabolites, or biomarkers) or microorganisms (viruses, bacteria, and parasites) in wastewater. The first and most developed application is the estimation of illicit drug consumption in communities or populations, but it can be used to measure both consumption and exposure to a wide range of substances and pathogens. Its recent application to measure the severe acute r…