1. It is shown that free haematins will react with nitric oxide under certain conditions giving compounds with characteristic absorption spectra. 2. The reactions of nitric oxide with both protohaematin and urohaematin were examined. In acid solution each of these haematins changes colour from reddish brown to a bright red in the presence of nitric oxide, and two strong absorption bands appear ...

The aim of the present study was to evaluate the accuracy, in comparison with a reference method, of the Nellcor N-20P pulse oximeter in the assessment of oxyhaemoglobin saturation (Sa,O2). Sa,O2 was monitored at rest by the Nellcor N-20P pulse oximeter in 100 subjects (82 males, mean age 68+/-12 yrs) consecutively enroled. At the same time, an arterial blood sample was collected for the measur...

A complete pH and blood gas analysis of arterial and mixed venous blood may comprise more than forty different quantities. We have selected sixteen, including patient temperature. The arterial oxygen tension group includes the oxygen tension, fraction of oxygen in inspired air, and fraction of mixed venous blood in the arterial (total physiological veno-arterial shunting). The haemoglobin oxyge...

The present investigation was therefore extended to examine the effects of p-benzoquinone and 2,6-dimethoxybenzoquinone on cat liver mitochondria (Chappell & Hansford, 1972). It was shown that both quinones are potent inhibitors of mitochondria1 respiration. Mitochondria could be protected by an equimolar concentration of cysteine. A predictable consequence of the presence of quinones is the fo...

Previous studies have documented structural and functional changes induced by ethanol-erythrocyte membrane interaction. In order to perform an in vitro study on the effect of different ethanol concentrations on erythrocyte hemorheologic properties, blood samples were collected from 21 male donors at the Hospital of Santa Maria. Whole blood aliquots were incubated with ethanol solutions of risin...

Lipoperoxide concentration in erythrocytes from workers occupationally exposed to lead (mean blood lead concentration 57.1 (SD 17.6) micrograms/dl) was significantly higher than that in controls. It was not different in plasma from the two groups. The activity of superoxide dismutase (SOD) and catalase in erythrocytes from workers exposed to lead was significantly lower than that of control sub...

seems more likely that it is due to the formation of a pigment in the body from the condensation products of the drug itself (Marshall and Walzl, 1937). Posner and his colleagues (1938) described a highly unstable form of methsemoglobin which they thought, might account for cyanosis in some of these cases. In many instances, however, the cyanosis is associated with sulphor methaemoglobinaemia (...

1. A procedure for the rapid, accurate estimation of haptoglobin in serum and purified preparations is described, based on the peroxidase activity of haemoglobin in its complexes with haptoglobin. 2. Hydrogen peroxide, guaiacol and methaemoglobin reagents are used, under well-defined conditions which reduce the peroxidase activity of free haemoglobin essentially to zero. The reaction is followe...

AIMS Early phagocytosis of glucose-6-phosphate dehydrogenase (G6PD)-deficient erythrocytes parasitized by Plasmodium falciparum were shown to protect G6PD-deficient populations from severe malaria. Here, we investigated the mechanism of a novel antimalarial series, namely 3-[substituted-benzyl]-menadiones, to understand whether these NADPH-consuming redox-cyclers, which induce oxidative stress,...

Previous speakers have outlined the genetics and molecular pathology of the defects of enzymes of the glycolytic pathway. Recent work has shown that not only is glycolysis necessary for maintaining the integrity of the red cell and preventing the denaturation of haemoglobin by methaemoglobin formation or oxidation of the sulphydryl groups but it is intimately concerned with the control of oxyge...