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1.
Oral Oncol ; 82: 48-52, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29909901

RESUMEN

Thyroid angiosarcoma (TAS) is rare and represents a very aggressive malignancy. Its rarity is principally linked to two major pitfalls. Firstly, TAS histopathology diagnosis can be difficult; second, the limited clinical experience with this condition can make its management complex. We conducted a detailed systematic review, focusing on the knowledge available regarding TAS etiopathogenesis, treatment options and prognosis. The aim is to present the main TAS characteristics and to summarize the clinical experiences described worldwide, in order to provide a useful clinical tool.


Asunto(s)
Hemangiosarcoma/diagnóstico , Neoplasias de la Tiroides/diagnóstico , Detección Precoz del Cáncer , Hemangiosarcoma/terapia , Humanos , Pronóstico , Neoplasias de la Tiroides/terapia
2.
Biochim Biophys Acta ; 596(3): 331-7, 1980 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-6767495

RESUMEN

Four groups of rats were used in a nutritionally-controlled study of effects of chronic ethanol consumption on brain membrane lipid composition. Rats chronically consuming ethanol were fed high-nutrient or low-thiamin, low-protein diets. After 4 months, lipid analyses were performed on brains, brain microsomes and myelin from each group and from pair-fed, non-ethanol controls. Among the effects of ethanol was an increase of the relative proportion of cholesterol in microsomal lipids while there was decrease of it in myelin. Ethanol also increased plasmenylethanolamine while decreasing phosphatidylethanolamine proportions in myelin and in whole brain lipids, decreased the total lipid phosphorus of whole brain, and elevated the proportion of phosphatidylserine in microsomal and whole brain lipids. Effects of poor diet generally did not interfere with ethanol effects except in the case of microsomal lipids, where it apparently prevented an ethanol-induced increase in proportion of cholesterol. These changes may be adaptive responses to the fluidizing effect of ethanol on membranes.


Asunto(s)
Química Encefálica , Encéfalo/metabolismo , Etanol/farmacología , Lípidos/análisis , Lípidos de la Membrana/análisis , Desnutrición Proteico-Calórica/metabolismo , Deficiencia de Tiamina/metabolismo , Animales , Encéfalo/efectos de los fármacos , Membrana Celular/análisis , Masculino , Microsomas/análisis , Vaina de Mielina/análisis , Fosfolípidos/análisis , Ratas
3.
Biochim Biophys Acta ; 730(2): 263-70, 1983 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-6303406

RESUMEN

Spin-labeled aqueous dispersions of total phospholipid extracts from whole brains of hibernating hamsters and rats chronically consuming ethanol were compared with dispersions from control animals. Order parameter values and approximate rotational correlation times for the nitroxide spin labels indicated that ethanol consumption results in an adaptive decrease in bilayer membrane fluidity, while hibernation produces increases in fluidity. Since it has been proposed that changes in plasmenylethanolamine such as those seen with hibernation play a role in the homeoviscous adaptation of brain membranes, electron spin resonance studies using aqueous phospholipid dispersions containing equimolar mixtures of rat brain phosphatidylethanolamine and phosphatidylcholine, or synthetic dioleylphosphatidylcholine and dioleylphosphatidylethanolamine, and brain plasmenylethanolamine were performed. The molar amount of plasmenylethanolamine was varied within the ethanolamineglycerophospholipid fraction of each dispersion. Order parameter values of spin labels in liposomes containing brain phosphatidylcholine and phosphatidylethanolamine increased in parallel with increases in plasmenylethanolamine concentrations, indicating that fluidity was decreasing. Liposomes composed of synthetic dioleyl phospholipids exhibited biphasic changes in order parameter (S) values as plasmenylethanolamine replaced the diacyl form. Below 30% (mol%) plasmenylethanolamine, S values decreased, while above 30%, S values were seen to increase; indicating an initial fluidization, followed by a decrease in fluidity.


Asunto(s)
Química Encefálica/efectos de los fármacos , Etanol/farmacología , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Plasmalógenos/metabolismo , Animales , Cricetinae , Espectroscopía de Resonancia por Spin del Electrón , Hibernación , Matemática , Mesocricetus , Ratas
4.
Lipids ; 13(4): 294-6, 1978 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-661514

RESUMEN

The effects of storage on rat brain lipid composition were studied in terms of ethanolamine glycerophospholipid, cerebrosides, and cholesterol. Rat brains were stored at several combinations of temperature and time. Storage conditions were: 2 hr at room temperature, 12 hr of refrigeration, and a sequence of both of these conditions. Two-dimensional thin layer chromatography followed by colorimetric analyses of eluted lipids were used to determine molar ratios of phosphatidylethanolamine, ethanolamine plasmalogen, lysophosphatidylethanolamine, and cerebrosides. Cholesterol was also determined. These studies revealed small but significant increases in lysophosphatidylethanolamine in all three cases. A slight increase was also noted in the apparent molar proportion of cholesterol.


Asunto(s)
Química Encefálica , Lípidos/análisis , Preservación Biológica , Animales , Cerebrósidos/análisis , Colesterol/análisis , Masculino , Fosfatidiletanolaminas/análisis , Plasmalógenos/análisis , Ratas , Temperatura , Factores de Tiempo
5.
Lipids ; 14(12): 1027-31, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-530000

RESUMEN

Microsomal and myelin membrane fractions were prepared from the brains of warm-adapted (room temperature) and hibernating Syrian Hamsters (Mesocricetus auratus). Ethanolamineglycerophospholipids were isolated and subjected to a fractionation scheme to separate the fatty acids of the plasmenylethanolamine and the phosphatidylethanolamine 1 and 2 positions. The major changes in microsomal phosphatidylethanolamine with hibernation were relative increases in 18:1 at the 1 position and 20:4(n-6) in the 2 position. In myelin, 18:1 increased and 18:0 decreased at the 1 position while the 2 position showed an increase in 16:0 and a decrease in 22:6(n-3). Plasmenylethanolamine fatty acids also changed in microsomes and myelin although the magnitudes were not as great and confined to longer chain fatty acids. In both membranes, fatty acid alterations were position-specific, and no new types of fatty acids were introduced at any position.


Asunto(s)
Química Encefálica , Ácidos Grasos/análisis , Hibernación , Membranas Intracelulares/análisis , Lípidos de la Membrana/análisis , Fosfatidiletanolaminas/análisis , Animales , Membrana Celular/análisis , Cricetinae , Masculino , Mesocricetus , Microsomas/análisis , Vaina de Mielina/análisis
10.
J Neurochem ; 40(4): 1100-5, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6834040

RESUMEN

Synaptosomes and mitochondria were isolated from the brains of warm-adapted, hibernating, and cold-acclimated golden hamsters (Mesocricetus auratus). Lipid extracts of these subcellular fractions were prepared and assayed for plasmenylethanolamine (ethanolamine plasmalogen) and cholesterol levels. The ganglioside composition of synaptosomes was also determined. Samples from the hibernating animals showed characteristic changes in lipid composition. These changes include decreases in plasmenylethanolamine levels and a shift in the ganglioside composition toward a higher percentage of the more polar gangliosides. Those animals which were exposed to cold and did not hibernate (cold-acclimated) showed no such changes. Fatty acid analyses of synaptosomal and mitochondrial ethanolamine glycerophospholipids demonstrated a similar trend. Samples from hibernators showed decreases in 16:0, 18:0, and 22:6 (n-3), and increases in 16:1, 18:1, and 20:4 (n-6) fatty acids. No changes were detectable in samples from cold-acclimated animals, indicating that hibernating and cold-acclimated hamsters represent chemically distinct populations.


Asunto(s)
Aclimatación , Encéfalo/fisiología , Hibernación , Metabolismo de los Lípidos , Mitocondrias/metabolismo , Sinaptosomas/metabolismo , Animales , Frío , Cricetinae , Femenino , Gangliósidos/metabolismo , Mesocricetus , Fosfolípidos/metabolismo
11.
Neurochem Res ; 10(4): 563-9, 1985 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-4000399

RESUMEN

Experimental spinal cord trauma was produced in 3-month-old SS-1 miniature pigs by dropping a 25 g weight from a height of 20 cm upon the exposed spinal cord. The histological lesion consisted of edema and hemorrhage. Phospholipid concentration and composition, cholesterol concentration and phospholipid fatty acid composition were determined in whole spinal cord 3 hours after injury, and in spinal cord myelin 5 hours after injury. Three hours after injury phospholipid and cholesterol concentration were decreased by about 14% in the whole spinal cord. Trauma had no effect on the phospholipid composition of whole spinal cord and myelin. Fatty acid composition of myelin also did not change after injury, and changed very slightly in the whole spinal cord. It is concluded that edema following spinal cord trauma is much more extensive than previously assumed. Furthermore, peroxidation of membrane lipid fatty acids does not appear to be a significant factor in spinal cord pathology 3 hours after injury.


Asunto(s)
Fosfolípidos/análisis , Traumatismos de la Médula Espinal/metabolismo , Médula Espinal/análisis , Animales , Fenómenos Químicos , Química , Colesterol/análisis , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/análisis , Vaina de Mielina/análisis , Porcinos , Porcinos Enanos
12.
J Nutr ; 109(3): 480-8, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-430250

RESUMEN

Three experiments were performed to investigate the possibility of a physiological relationship between zinc and essential fatty acids (EFA). Male weanling rats were fed diets low in zinc, EFA or both and their growth rates, dermal scores and tissue fatty acid profiles determined. In experiment 1, a basal soybean protein diet containing 7 ppm of added zinc and approximately 300 ppm EFA was used in a 2 X 2 factorial design: low Zn-low EFA; adequate Zn-low EFA; low Zn-adequate EFA and adequate Zn-adequate EFA. The low zinc status accentuated signs of EFA deficiency, including dermal lesions and growth rate, but it had no significant effect on the fatty acid profile in plasma. In experiment 2, a basal casein diet containing approximately 25 ppm of EFA and less than 1 ppm of zinc, was used in a similar design. For 7 weeks two groups of weanling rats were fed ad libitum either a diet adequate in Zn and low in EFA or a diet adequate in all nutrients. From 7 to 12 weeks zinc was removed from one-half of each group and all were pair-fed to the intake of the low zinc-low EFA group. Zinc deficiency accentuated dermal lesions in the group deprived of EFA and caused enlarged joints suggestive of an arthritic-like syndrome. In experiment 3, an egg albumin based diet containing approximately 25 ppm EFA and less than 1 ppm of zinc was used in a 2 X 2 factorial design. No signs of fatty acid deficiency occurred in 5 weeks with adequate zinc. Zinc and EFA deficiency accentuated dermal scores and severely depressed growth. Zinc deficiency increased the proportion of arachidonic acid in foot skin especially in the EFA deficient group. It is concluded that there is a physiological interaction between Zn and essential fatty acids.


Asunto(s)
Ácidos Grasos Esenciales/metabolismo , Zinc/metabolismo , Animales , Peso Corporal , Dermatitis/etiología , Dieta , Interacciones Farmacológicas , Ácidos Grasos Esenciales/sangre , Ácidos Grasos Esenciales/deficiencia , Masculino , Ratas , Zinc/sangre , Zinc/deficiencia
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