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Free radical reactions in erythrocytes of stroke patients
FREE RADICAL REACTIONS IN ERYTHROCYTES OF STROKE PATIENTS S. G. Imre, Z. Szikszai and I. Fekete Department of Pathophysiology and Department of Neurology, University Medical School of Debrecen, Hungary
PSAMMOMA BODIES OF HUMAN CHOROID PLEXUS D Korzhevsky Department qf Morpholom, Institute of Experimental Medicine, St. Petersburg. Russia Multiple psammoma bodies (PB) are commonly found in choroid plexus of aged human. The causes and mechanism of their formation are yet unclear. Present investigation is devoted to PB formation in human telencephalic choroid plexus. 130 choroid plexuses from different age groups were studied using histochemical and immunocytochemical (reaction to vimentin, smooth muscle actin, von Villebrand factor) methods. PB formation was found to start during childhood. In early stages of development PBS are not calcified and are formed by fibroblasts posessing a number of cytologlcal diversities from fibroblasts of the surrounding connective tissue. Cytoplasm of PB-forming fibroblasts contains great amount of vimentin Comparison of common morphology and vimentin expression of PBforming cells to meningioma cells leads to suggestion on existence of special population of fibroblasts-meningocytes, which have an ability to form PBS in choroid plexus, meninges and meningocytic tumors. It is possible that some metabolic and barrier alterations cause activation of this special meningocytes and induce PB formation.
Investigations were carried out to elucidate the biochemical background of reduced deformability of erythrocytes in 40 acute ischemic stroke patients and in 20 healthy subjects. Deformability was characterized by determining the relativ cell transit time (RCTT) and initial f&ration rate (IFR) of erythrocytes with St. George filtiometer. Malondialdehyde (MDA) content of erythrocytes was measured as a marker of lipidperoxidation before and after the autoxidative test as described previously (Stroke, 25, 2416, 1994). The RCTT increased, the IFR decreased significantly in patients. The effect of autoxidative test on the MDA content has been observed to be minimal, however the initial MDA content was significantly higher in patients. These findings suggest that the free radical reactions play a central role in the background of rheological alterations found in stroke patients
OXIDATIVE STABILITY OF LIPOSOMES PREPARED FROM MARINE PHOSPHOLIPIDS E. Ltivaas, J. K. MidtbPr, and T. Strom Institute of Technology, The Norwegian College of Fishery Science, Universify of Tromsti, Norway
CAPSAICIN ACTIVATES HEAT LOSS AND HEAT PRODUCTION SIMULTANEOUSLY AND INDEPENDENTLY IN RATS S. Inoue, A. Kobayashi, 71 Osaka, Y Namba, S. Kimura and TH.Lee National Institute of Health and Nutrition, Showa Women’s University Graduate School, and Chonnam National University, Tokyo and Kwangiu, Japan and Korea
All liposomes undergo autoxidation that is accelerated by elevated temperature, light, metal ions, and free radical initiators. As a result there is a dramatic change in liposome permeability, and development of toxic degradation products that make the liposome preparation useless as a pharmaceutical vehicle, cosmetological component. Marine ingredient or a food/feed phospholipids isolated from cod roe predominantly consist of phosphatidylcholin (62%) and cholesterol (33%), and contains a high amount of polyunsaturated fatty acids (20:5 (16%) and 22:6 (31%)). Such liposomes have a high inherent instability which may be exploited for the examination of various types of oxidative stress and in the evaluation of antioxidant efficacy. We have investigated the oxidative stability of liposomes prepared from marine phospholipids in the presence of a large number of antioxidants including metal chelators (citric acid, EDTA, polyamines, curcumin, phytic acid, desferal), phenols, polyphenols and flavonoids (rutin, quercetin, ethoxyquin, BHT, BHA) as well as cc-tocophenol, ascorbic acid, uric acid, thiourea, and taurin. We describe a strategy for investigating oxidative stability based on the combined use of a number of techniques, including TBARS, diene conjugation, Clark oxygen electrode, and the measurement of peroxides.
There are controversy about the effect of capsalcin on thermoregulation. This study was undertaken to clarify the mechanism of capsaicin on heat production and heat loss using Wistar famale rats. Subcutaneous administration of capsaicin (5mglkg)immediately increased the temperature of the tail skin (Tsk) for 2 hrs in urethane-anesthetized rats, suggesting increase in heat loss. Oxygen consumption, an index of heat production, also immediately mcreased after the capsaicin injection, and this increase lasted more than 10 hrs. Colonic temperature (Tco) decreased within one hour after the injection, and this decrease was followed by a longlasting hyperthermic period. Adrenal demedullatlon largely attenuated the capsaicin-induced increase in oxygen sympathetic denervation of the and consumption, interscapular brown adipose tissue (IBAT) partly did SO. However, capsaicin-induced heat loss was normal in these rats. To prevent the capsaicin-induced change in Tsk, we cutaneous vasodilation by warming and maximized administration of hexamethonium. Capsaicin did not further increase Tsk but normally induced heat production in these rats. Tco gradually rose without a hypothermic period. Thus, capsaicin- simultaneously increased heat loss and heat nroduction. and inhibition of one response did not affect the other. These finding suggest that capsaicin simultaneously and independently activates networks for heat loss and heat production So
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PSAMMOMA BODIES OF HUMAN CHOROID PLEXUS D Korzhevsky Department qf Morpholom, Institute of Experimental Medicine, St. Petersburg. Russia Multiple psammoma bodies (PB) are commonly found in choroid plexus of aged human. The causes and mechanism of their formation are yet unclear. Present investigation is devoted to PB formation in human telencephalic choroid plexus. 130 choroid plexuses from different age groups were studied using histochemical and immunocytochemical (reaction to vimentin, smooth muscle actin, von Villebrand factor) methods. PB formation was found to start during childhood. In early stages of development PBS are not calcified and are formed by fibroblasts posessing a number of cytologlcal diversities from fibroblasts of the surrounding connective tissue. Cytoplasm of PB-forming fibroblasts contains great amount of vimentin Comparison of common morphology and vimentin expression of PBforming cells to meningioma cells leads to suggestion on existence of special population of fibroblasts-meningocytes, which have an ability to form PBS in choroid plexus, meninges and meningocytic tumors. It is possible that some metabolic and barrier alterations cause activation of this special meningocytes and induce PB formation.
Investigations were carried out to elucidate the biochemical background of reduced deformability of erythrocytes in 40 acute ischemic stroke patients and in 20 healthy subjects. Deformability was characterized by determining the relativ cell transit time (RCTT) and initial f&ration rate (IFR) of erythrocytes with St. George filtiometer. Malondialdehyde (MDA) content of erythrocytes was measured as a marker of lipidperoxidation before and after the autoxidative test as described previously (Stroke, 25, 2416, 1994). The RCTT increased, the IFR decreased significantly in patients. The effect of autoxidative test on the MDA content has been observed to be minimal, however the initial MDA content was significantly higher in patients. These findings suggest that the free radical reactions play a central role in the background of rheological alterations found in stroke patients
OXIDATIVE STABILITY OF LIPOSOMES PREPARED FROM MARINE PHOSPHOLIPIDS E. Ltivaas, J. K. MidtbPr, and T. Strom Institute of Technology, The Norwegian College of Fishery Science, Universify of Tromsti, Norway
CAPSAICIN ACTIVATES HEAT LOSS AND HEAT PRODUCTION SIMULTANEOUSLY AND INDEPENDENTLY IN RATS S. Inoue, A. Kobayashi, 71 Osaka, Y Namba, S. Kimura and TH.Lee National Institute of Health and Nutrition, Showa Women’s University Graduate School, and Chonnam National University, Tokyo and Kwangiu, Japan and Korea
All liposomes undergo autoxidation that is accelerated by elevated temperature, light, metal ions, and free radical initiators. As a result there is a dramatic change in liposome permeability, and development of toxic degradation products that make the liposome preparation useless as a pharmaceutical vehicle, cosmetological component. Marine ingredient or a food/feed phospholipids isolated from cod roe predominantly consist of phosphatidylcholin (62%) and cholesterol (33%), and contains a high amount of polyunsaturated fatty acids (20:5 (16%) and 22:6 (31%)). Such liposomes have a high inherent instability which may be exploited for the examination of various types of oxidative stress and in the evaluation of antioxidant efficacy. We have investigated the oxidative stability of liposomes prepared from marine phospholipids in the presence of a large number of antioxidants including metal chelators (citric acid, EDTA, polyamines, curcumin, phytic acid, desferal), phenols, polyphenols and flavonoids (rutin, quercetin, ethoxyquin, BHT, BHA) as well as cc-tocophenol, ascorbic acid, uric acid, thiourea, and taurin. We describe a strategy for investigating oxidative stability based on the combined use of a number of techniques, including TBARS, diene conjugation, Clark oxygen electrode, and the measurement of peroxides.
There are controversy about the effect of capsalcin on thermoregulation. This study was undertaken to clarify the mechanism of capsaicin on heat production and heat loss using Wistar famale rats. Subcutaneous administration of capsaicin (5mglkg)immediately increased the temperature of the tail skin (Tsk) for 2 hrs in urethane-anesthetized rats, suggesting increase in heat loss. Oxygen consumption, an index of heat production, also immediately mcreased after the capsaicin injection, and this increase lasted more than 10 hrs. Colonic temperature (Tco) decreased within one hour after the injection, and this decrease was followed by a longlasting hyperthermic period. Adrenal demedullatlon largely attenuated the capsaicin-induced increase in oxygen sympathetic denervation of the and consumption, interscapular brown adipose tissue (IBAT) partly did SO. However, capsaicin-induced heat loss was normal in these rats. To prevent the capsaicin-induced change in Tsk, we cutaneous vasodilation by warming and maximized administration of hexamethonium. Capsaicin did not further increase Tsk but normally induced heat production in these rats. Tco gradually rose without a hypothermic period. Thus, capsaicin- simultaneously increased heat loss and heat nroduction. and inhibition of one response did not affect the other. These finding suggest that capsaicin simultaneously and independently activates networks for heat loss and heat production So
84