Search results for "Hydrogen"
showing 10 items of 4254 documents
Following Hydrogen Cyanide in the Valencian Country (1907-1933): Risk, Accidents and Standards in Fumigation
2019
Abstract Pests had represented a major problem in agriculture for centuries, but the huge changes in the food chain around the late nineteenth century intensified their effects in a totally unprecedented way and many new chemical substances were introduced in the attempt to control them. In this paper I will focus on the implementation of hydrogen cyanide, a highly toxic pesticide which has not received particular consideration from researchers to date. I shall analyse the introduction of this pesticide in the Valencian Country and focus on the attention given to the safety of workers and consumers. I aim to examine the role of the poison in its different uses and analyse the impact of each…
Biochemical and histological alterations of cellular metabolism from jerboa (Jaculus orientalis) by 2,4-dichlorophenoxyacetic acid: Effects on d-3-hy…
2007
?; International audience; 2,4-Dichlorophenoxyacetic acid (2,4D) is one of the widely used herbicide of the phenoxy family with possible startling number of adverse effects on species other than the weeds which is designed to kill. The effects of 2,4D were investigated in jerboa (Jaculus orientalis), a wild animal of subdesert highlands. The jerboas have been daily treated intraperitonally with 2,4D 3 mg/kg body weight for 4 weeks. Plasmatic markers, and antioxidants defences systems were assessed and histological alterations were evaluated. The in vivo and in vitro effects of 2,4D on the mitochondrial D-3-hydroxybutyrate dehydrogenase (BDH) were also determined. Our results showed a strong…
The Presence of Gestational Diabetes is Associated with Increased Detection of Anti-HLA-class II Antibodies in the Maternal Circulation
2006
Problem Gestational diabetes (GD) may be associated with temporarily reduced immune tolerance toward alloantigens for the time of pregnancy. The aim of this study was to assess anti-HLA-class I and -II antibodies as markers for an aberrant immunostimulation in women with GD. Method of study The percentage of anti-HLA-class I and -II antibodies was estimated in women with GD, normal term delivery and fetal distress, which was confirmed by demonstrating low cord blood pH for this patient group. These antibodies may cross the placental barrier and cause interleukin-6 (IL-6) release from fetal monocytes by cross-linking monocytes with antibody-loaded cells. Therefore we estimated the percentage…
NAD- and NADP-linked dehydrogenases in the sciatic nerve of rats injected with di-isopropylfluorophosphate.
1966
Is there a critical tissue oxygen tension for bioenergetic status and cellular pH regulation in solid tumors?
1996
Bioenergetic and metabolic status have been correlated with tissue oxygenation in murine fibrosarcomas (FSaII) of varying sizes (44-600 mm3). Ratios of beta-nucleoside triphosphates to inorganic phosphate (beta NTP/P) and phosphocreatine to inorganic phosphate (PCr/P(i)) ratios derived from 31P nuclear magnetic resonance spectroscopy (NMR) were positively correlated to median tissue O2 tension (pO2) values using O2-sensitive needle electrodes. pH declined during growth with intracellular acidosis being evident in tumors350 mm3. Whereas lactic acid formation greatly contributed to this decline in small and medium-sized tumors, adenosine triphosphate (ATP) hydrolysis and slowing down of the a…
Intracellular acidosis in murine fibrosarcomas coincides with ATP depletion, hypoxia, and high levels of lactate and total Pi
1994
Bioenergetic and metabolic status of murine FSaII tumours were evaluated using 31P MRS, acid extracts ('global' techniques) and quantitative bioluminescence ('microregional' assay). Data obtained from s.c. tumours of varying sizes (44-600 mm3) have been correlated with the oxygenation status evaluated using O2-sensitive needle electrodes. beta-NTP/Pi and phosphocreatine (PCr)/Pi ratios derived from 31P MRS were positively correlated to the median tissue pO2 values. pH declined during growth with intracellular acidosis being evident in tumours > 350 mm3. Whereas lactic acid formation greatly contributed to this decline in small- and medium-sized tumours, ATP hydrolysis and slowing down of th…
Prediction of dilutional acidosis based on the revised classical dilution concept for bicarbonate
2004
Due to the controversy surrounding the term dilutional acidosis, the classical dilution concept for bicarbonate has been rigorously revised for the prediction of pH, actual bicarbonate concentration, and base excess. In the algorithms derived for buffer solutions, blood, and whole body (1-, 2-, and 3-fluid compartment), only bicarbonate is considered. On dilution at constant Pco2, the final concentration of bicarbonate is the sum in terms of pH, due to the following processes: dilution, formation from chemical reaction with the nonbicarbonate buffers phosphate, hemoglobin, and plasma proteins, and transfer from erythrocytes and interstitial fluid to plasma. At constant Pco2, the level of c…
Base Excess and Lactate Concentration in Infusion Solutions and Blood Products
2002
Oxidative stress induces myeloperoxidase expression in endocardial endothelial cells from patients with chronic heart failure.
2009
Increased oxidative stress has been implicated in the pathogenesis of a number of cardiovascular diseases. Recent findings suggest that myeloperoxidase (MPO) may play a key role in the initiation and maintenance of chronic heart failure (CHF) by contributing to the depletion of the intracellular reservoir of nitric oxide (NO). NO consumption through MPO activity may lead to protein chlorination or nitration, leading to tissue damage. Primary cultures of human endocardial endothelial cells (EEC) obtained at heart transplantation of patients with CHF and human umbilical vein endothelial cells (HUVEC) were subjected to oxidative stress by incubation with hydrogen peroxide at non lethal (60 mic…
Expression of R-3-hydroxybutyrate dehydrogenase, a ketone body converting enzyme in heart and liver mitochondria of ruminant and non-ruminant mammals
1992
1. The properties of rat liver and bovine heart R-3-hydroxybutyrate dehydrogenase (BDH) have been extensively studied in the past 20 years, but little is known concerning the biogenesis and the regulation of this dehydrogenase over different species. 2. In addition, controversial results were often reported concerning the activity, the level and the subcellular location of this enzyme in ruminants. 3. BDH activity found in liver and kidney mitochondria from ruminants (cow and sheep) is low, while it is much higher in rat. 4. However, the enzyme activity is detected in microsomes and in cytosol of liver and of kidney cells from ruminants. These activities are not correlated to ketonaemia lev…