Search results for "Concentration."

Synthesis of azoxystrobin transformation products and selection of monoclonal antibodies for immunoassay development

2012

The use of agrochemicals for crop protection may result in the presence of toxic residues in soils and aquatic environments, besides in foodstuffs. Most often just the parent compound is included in the definition of pesticide residue, even though chemicals resulting from biotransformation and degradation routes might also be of toxicological relevance. Azoxystrobin is a broad-spectrum systemic fungicide widely used worldwide to combat pathogenic fungi affecting plants. We herein report the synthesis and detailed chemical characterization of several of the most relevant metabolites and degradates of azoxystrobin. These compounds were further employed as ligands for screening a collection of…

An epidemiological study exploring a possible impact of treatment with ACE inhibitors or angiotensin receptor blockers on ACE2 plasma concentrations

2020

Tagesprofile von Plasmaaldosteron,-Cortisol, -Renin, -Angiotensinogen und -Angiotensinasen bei Normalpersonen

1976

Plasma cortisol and renin were estimated in 1 h intervals, plasma aldosterone, angiotensinogen and angiotensinases in 3 h intervals over periods of 24 h in six normal volunteers (age 20-26) under control conditions and subsequently under suppression of ACTH release by dexamethasone. Highest cortisol levels were found around 7 a.m., minimum levels between 9 p.m. and 1 a.m. Dexamethasone reduced cortisol to constantly low concentrations. Aldosterone was highest around 4 a.m. under control conditions and under dexamethasone, and showed lowest concentrations between 4 and 10 p.m. There were no significant differences between mean aldosterone concentrations at corresponding time points of the co…

Abnormal Nailfold Capillaries in Patients after Hand Transplantation

2020

Background: The development of graft vasculopathy may play a role in the long-term deterioration of hand grafts. The aim of study was to examine the patterns of the nailfold capillaries in hand transplant recipients. Methods: the study was performed on six patients who received hand transplantation. To normalize for the effect of immunosuppression an age- and sex-matched group of 12 patients with active kidney transplant was selected. As an additional control group, 12 healthy volunteers were recruited. Nailfold videocapillaroscopy was performed in all participants. Additionally, serum concentrations of vascular endothelial growth factor (VEGF) were measured. Results: Videocapillaroscopic e…

Possible reason for preferential damage to renal tubular epithelial cells evoked by amphotericin B

1996

An important determinant of nephrotoxicity, which is the major complication of long-term amphotericin B treatment, is dysfunction of distal tubular epithelial cells. The underlying cause for this rather selective damage to the cells is unknown. In the present investigation, it was shown that kidney epithelial cells were initially damaged by amphotericin B at concentrations of 2.5 to 10 micrograms/ml, as demonstrable by a dramatic drop in cellular K+ levels. Cells could recover from the initial toxic action of the polyene if they were kept in medium of neutral pH, and cellular K+ levels returned to normal after 6 h. However, the recovery mechanisms failed at lower pHs of 5.6 to 6.0. At low p…

Early postoperative substitution procedure of the antioxidant ascorbic acid.

2005

Postoperatively reduced concentration of ascorbic acid (AA) in plasma (or =45.5 micromol/l (or =800 microg/dl)) is commonly interpreted as increased metabolic requirements, but it is not shown yet that the patient benefits from a substitution toward normal levels of AA. This is due to the missing knowledge on how to substitute AA effectively to normal plasma values in postoperative patients. Therefore, a postoperative AA substitution procedure "overnight" to normal values in plasma was investigated on a postoperative intensive care unit (ICU) in a university hospital.Fifty-seven operated patients were randomly assigned to a control- or intervention group (CG and IG, respectively). In all pa…

Effects of polymorphisms in endothelial nitric oxide synthase and folate metabolizing genes on the concentration of serum nitrate, folate, and plasma…

2015

Abstract Objectives A number of studies have explored the effects of dietary nitrate on human health. Nitrate in the blood can be recycled to nitric oxide, which is an essential mediator involved in many important biochemical mechanisms. Nitric oxide is also formed in the body from l -arginine by nitric oxide synthase. The aim of this study was to investigate whether genetic polymorphisms in endothelial nitric oxide synthase (eNOS) and genes involved in folate metabolism affect the concentration of serum nitrate, serum folate, and plasma total homocysteine in healthy individuals after folic acid supplementation. Methods In a randomized double-blind, crossover study, participants were given …

Improving opportunities for effective management of gastro-oesophageal reflux disease

2002

The recent introduction of proton pump inhibitors has extraordinarily improved the therapeutic approach to gastro-oesophageal reflux disease. The concept of decreasing gastric acid secretion and increasing the pH in the lower oesophagus has been demonstrated to be therapeutically effective and the higher the level of pH achieved, the better the results. In spite of the evident efficacy of these molecules, there are still many patients who will continue to have symptoms despite medical treatment. Proton pump inhibitors suppress gastric acidity, but this effect shows a remarkable interindividual variation depending on different reasons. Thus, it is still possible to optimise medical therapy f…

Endothelial Cell Swelling and Brain Perfusion

1997

Background: Whereas the contribution of glial swelling to no-reflow conditions in the ischemic penumbra or during reperfusion after global ischemia is widely discussed, little is known about cell volume control of endothelial cells under reperfusion conditions. Methods: The effect of extracellular acidosis-a key mediator of secondary brain damage-on cell volume was studied in the GM7373 endothelial cell line. Experiments were performed at pH = 6.0 in the presence or absence of bicarbonate, and during exposure to inhibitors of specific transport systems such as ethyl isopropyl amiloride or 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid. Results: Endothelial swelling to 111.1 ± 3.4% was f…

pH stability of ophthalmic solutions.

2004

Background In this study, we evaluated the pH value of 17 ophthalmic solutions, and we investigated whether the pH of these solutions changed over time after the bottle was opened. Methods Fifteen bottles of each type of solution were chosen at random from different production lots. A 0.05-ml increment was taken from each bottle and was measured daily using a micropH 2002 Crison pH-meter over a period of 30 days. Results The results revealed differences between the pH values of the solutions; nine solutions presented pH values within ocular comfort range and eight solutions presented pH values between 3.5 and 6.4. Ten solutions presented non-statistically significant variations over time ( …