Evidence for a 5'-nucleotidase in human leukemic leukocytes

Fifteen preparations of leukocytes isolated from patients with chronic leukemia, 9 lymphogenic (CLL) and 6 myelogenous (CML), were tested for 5'-nucleotidase activity. The presence of 5'-nucleotidase was demonstrated in 5 cases: four CLL and one CML. The properties of this enzyme were similar to those of 5'-nucleotidase from other tissues: its activity was dependent on Mg2+, and was not inhibited by tartrate, could not be solubilized by freezing and thawing and the enzyme was active at alkaline pH. On the other hand, an enzyme active on 5'-AMP in acid medium, found in all preparations, shared several characteristics with acid phosphatase. It was inhibited by tartrate, was not affected by the absence of Mg2+ and was partially solubilized by freezing and thawing. © 1973.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Isolation and characterization of plasma membranes from human leukemic lymphocytes

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Lipid composition of plasma membranes from human leukemic lymphocytes

The specific activity of adenosine 5' monophosphatase and the concentrations of cholesterol, glucosylceramide, lactosylceramide and phospholipids were compared in the whole homogenates and in plasma membrane fractions in 4 preparations of human leukemic lymphocytes taken over a 1 yr period from a patient with chronic lymphocytic leukemia. There was a 69.5 fold enrichment of the specific activity of adenosine 5' monophosphatase in plasma membrane fractions. This enzyme appeared to be the best plasma membrane marker of all compounds studied. The increase in lactosylceramide concentration in the plasma membranes was 34.4 fold. It was significantly higher than that of glucosylceramide. The enrichment of glucosylceramide in the plasma membranes was similar to that of cholesterol and total phospholipids. The pattern of individual phospholipids in the plasma membrane fraction, as compared with the whole homogenate, was characterized by a decrease in phosphatidylcholine and an increase in sphingomyelin.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Bovine and human endothelial cell growth on collagen microspheres and their infection with the rickettsia Cowdria ruminantium: prospects for cells and vaccine production.

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

The effect of vitamin E supplementation of cow diets containing rapeseed and linseed on the prevention of milk fat oxidation.

Two experiments involving lactating Holstein cows were carried out to quantify the effect of a 550-g supplement of lipids from extruded rapeseed and linseed on milk fatty acid profiles and the susceptibility of milk fat to oxidation. The effect of a daily oral supplement containing 9616 IU of vitamin E (all-rac-alpha-tocopheryl acetate) on milk alpha-tocopherol and protection against oxidation was also evaluated. The intake of oilseeds decreased protein and fat contents in milk, and the proportion of all C18 fatty acids increased. The trans isomers were 2.7 and 10.76% of the milk fatty acids, respectively, for cows fed the control diet and the diet containing extruded rapeseed and linseed. The ratio of oleic to palmitic acid was doubled, and the resistance to oxidation was reduced by 30 to 40% in both experiments. The dietary vitamin E supplement increased the alpha-tocopherol concentration in milk by about 45% and was sufficient to prevent milk fat depression and oxidation. The diet containing oilseeds and supplemented with an adequate amount of vitamin E allowed cows to yield milk that could be used to manufacture butter with high oleic acid content, good spreadability, and resistance to oxidation

Constitutive release of metalloproteinase-9 (92-kd Type IV collagenase) by Kaposi's sarcoma cells

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Cerebral metabolic correlates of four dementia scales in Alzheimer's disease

© 2005 Springer Medizin Verlag Gmb

Cerebral metabolic correlates of four dementia scales in Alzheimer's disease

Different scales can be used to evaluate dementia severity in Alzheimers disease (AD). They do assess different cognitive or functional abilities, but their global scores are frequently in mutual correlation. Functional imaging provides an objective method for the staging of dementia severity. Positron emission tomography was used to assess the relationship between brain metabolism and four dementia scales that reflect a patients global cognitive abilities (mini mental state), caregivers evaluation of cognitive impairment (newly designed scale), daily living functioning (instrumental activities of daily living) and global dementia (clinical dementia rating). We wondered whether different clinical dementia scales would be related to severity of metabolic impairment in the same brain regions, and might reflect impairment of common cognitive processes. 225 patients with probable AD were recruited in a prospective multicentre European study. All clinical scales were related to brain metabolism in associative temporal, parietal or frontal areas. A factorial analysis demonstrated that all scales could be classified in a single factor. That factor was highly correlated to decrease of cerebral activity in bilateral parietal and temporal cortices, precuneus, and left middle frontal gyrus. This finding suggests that global scores for all scales provided similar information on the neural substrate of dementia severity. Capitalizing on the neuroimaging literature, dementia severity reflected by reduced metabolism in posterior and frontal associative areas in AD might be related to a decrease of controlled processes

Biological response of endothelial cells and its modulation by cytokines: prospects for therapy and bioprocesses.

Endothelial cells are involved in important pathological situations. They could be the target for infectious processes as for example in Cowdriosis, an important disease in cattle due to the rickettsia Cowdria ruminantium prevalent in the south of the Sahara. They are also connected to angiogenic processes related to tumor invasion.Our results indicate that AIDS related Kaposi sarcoma cells may be of endothelial origin. We conclude from our data the mobility of those cells, related to the expression of the metalloproteinases (especially the 92 kD form of the enzyme), is an important factor in Kaposi saroma dissemination and is the main factor limiting the scale up of Cowdriosis vaccine production in Bovine Umbilical Endothelial Cell line. We showed that PMA and TNF increased the 92 kD Metallaproteinase and that TGFβ, produced in an inactive form in cultures of Human Umbilical Vein Endothelial Cells, is a potential inhibitor of Kaposi sarcoma spreading, and could also be useful in improving our process for Cowdria ruminantium vaccine production, since it reduces the sensitivity of the cells to mechanical stress without affecting significantly the overall infectious process.JOURNAL ARTICLEinfo:eu-repo/semantics/publishe