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81.
The plasma metallothionein concentration was studied in renal transplant patients. These patients are submitted to an attack of free radicals catalyzed by metals such as copper, zinc, cadmium, and others. The function of metallothionein is to bind toxic metals inhibiting the attack of free radicals and oxidative stress that patients receiving renal transplants are submitted to. This is the reason for studying this protein in this work. The metalloprotein was separated from the plasma by thermoprecipitation and molecular exclusion chromatography with Sephadex G-75 followed by anionic-ionic exchange chromatographic purification with a CINa gradient. Identification was done by SDS electrophoresis in acrylamide gel with markers and commercial protein. Finally, determinations were made by atomic absorption, silver saturation method. In this work, determinations were made in the plasma of 11 patients before and 48 h and 1 and 2 weeks after renal transplantation. The same study was carried out in parallel in a control group of 11 blood donors. The results obtained show the existence in the plasma of metallothionein, with lower concentrations in patients than in controls (19 +/- 1.2 mg vs. 12 +/- 1.2 mg). The levels were lowest in the patient group analyzed 48 h after having received the transplant (6.34 mg) and had recovered slightly one and two weeks later. 相似文献
82.
Mateo R Beyer WN Spann JW Hoffman DJ Ramis A 《Journal of toxicology and environmental health. Part A》2003,66(14):1371-1389
Some of the adverse effects of lead (Pb) may be associated with oxidative damage of lipids, proteins, or DNA. In a previous study a linkage was observed between the susceptibilities of waterfowl species to Pb poisoning with oxidative stress. To investigate this relationship among the individuals of a single species, for 3 wk 4 groups of 12 mallards were fed diets containing high or low levels of vitamin E (20 or 220 UI/kg) and high or low levels of Pb (0 or 2 g/kg). During the first week of Pb exposure, mallards developed hemolytic anemia, and during the second week, signs of neurological impairment. Histological findings in the Pb-exposed mallards were hemosiderosis, demyelinization of sciatic and brachial nerves, and tumefaction of renal tubular epithelium with the presence of intranuclear inclusion bodies. Lipid peroxidation increased with Pb exposure in blood, liver, bile, and brain, but decreased in nerves. Glutathione (GSH) increased with Pb exposure in liver and bile, and its oxidized/reduced ratio only increased in bile. Pb exposure inhibited GSH peroxidase activity (GPX) in plasma, liver, and brain, and decreased protein thiols (PSH) in blood and liver. Vitamin E resulted in significantly lower lipid peroxidation in nerves of control birds relative to unsupplemented controls, but did not alleviate any sign of lead posioning. Pb-induced pathological changes associated with hepatic and nervous functions were significantly correlated with lower GPX activity and PSH concentrations in these tissues rather than lipid peroxidation. Data suggest that inhibition of antioxidant enzymes and interaction with sulfhydryl groups of proteins may play a more important role in Pb poisoning of waterfowl than lipid peroxidation. 相似文献
83.
Hervás I Bello P Fernández JM González-Cabezas P Flores D Torres MJ Cañete A Pérez-Velasco R Rivas A Alonso J Castel V Mateo A 《Revista espanola de medicina nuclear》2003,22(6):367-375
Langerhans cell histiocytosis (LCH) is a granulomatous disease which can involve multiples sites of the body. Diagnostic imaging is of utmost importance in the management of these patients. Up to now radiographic skeletal survey and bone scintigraphy (BS) have been used to assess bone involvement (both with low specificity). Magnetic resonance imaging (MRI) and CT have been used to assess visceral involvement but with the limitation that they cannot give information about the functional status. Recently somatostatin receptor scintigraphy (SSRS) has been proposed to detect active lesions and to monitor response to treatment. The aim of this study is to assess bone and somatostatin receptor scintigraphy in the detection of bone involvement in LCH in children. Twenty scintigraphies (12 SSRS and 8 BS) were performed in seven patients (3 girls and 4 boys) aged at diagnosis: 18 month-12 years (mean age 6 years). The findings obtained in the scintigraphies were compared with clinical evolution and other imaging techniques. Bone scintigraphy detected all the LCH bone lesions, and discovered one unknown lesion. SSRS scintigraphy visualised the active lesions in 3 patients (clinical and other imaging techniques were also positive). SSRS was negative in one patient classified as disease free and another in clinical remission. SSRS detected 2 new unknown bone lesions, but could not detect LCH bone lesions confirmed in other imaging techniques in 2 patients. Somatostatin receptor and Bone scintigraphy can be used to detect active LCH bone lesions in children and can help to monitor response to treatment. Further studies with more patients are needed to confirm the diagnostic usefulness of these techniques. 相似文献
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86.
Care of patients who have sustained a mild traumatic brain injury (MTBI) requires collaboration between the case manager, other disciplines, the patients, and their significant other. The case manager's knowledge of the evaluation tools that may be used to assess patient status in various phases of care is essential in planning and dealing with possible variances of care, which could affect outcomes of care. An overview of the etiology of MTBI, diagnosis, recovery, evaluation at various stages, outcome measurement, and examples of valid and reliable tools are presented. 相似文献
87.
Hervás Benito I Pérez Velasco R Vera Espallardo F Bello Arques P Saura Quiles A González Cabezas P Mateo Navarro A 《Revista espanola de medicina nuclear》2001,20(4):299-304
The primary vertebral osteosarcoma in adults is a rare tumor which represents less than 2% of all osteosarcomas. We present the cases of two men (40 and 33 years old) who began with pain and neurological compression symptoms. The imaging methods used to study the tumors were X-rays, CT, MRI and bone scintigraphy with 99mTc-HMDP. After the pathological diagnosis, the tumors were removed surgically and the treatment was completed with chemotherapy and radiotherapy. In this report the authors review the published cases of vertebral osteosarcoma, its epidemiology, clinical presentation and characteristics in the different imaging techniques. 相似文献
88.
Hervás Benito I Vera Espallardo F Rivas Sánchez A López Aznar D Saura Quiles A Muñoz M Bello Arques P Mateo Navarro A 《Revista espanola de medicina nuclear》2001,20(2):116-119
Thyroid hemiagenesis is a very infrequent abnormality. We present a case of Graves disease associated to a congenital hemiagenesis of the thyroid gland. The thyroid scintigraphy, ultrasonography and laboratory analysis (that showed the existence of thyroid hyperfunction and the present of thyroid stimulating antibodies) were decisive in the diagnosis. 相似文献
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90.
RATIONALE: Social isolation from weaning in the rat produces a variety of neurochemical and behavioural effects in the adult that in part parallel changes seen in human schizophrenia. OBJECTIVES: The study investigated the effects of central noradrenaline (NA) depletion by the selective neurotoxin, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4), on the behaviour of isolation-reared rats. METHODS: Male Lister hooded rats were reared singly or in groups after weaning. During week 2, the rats were tested in photocell activity cages and were then injected with DSP-4 (25 mg/kg, IP). During week 4, rats were tested in the open field under the following conditions: open field alone, with two novel stimuli (T1), and with a familiar and a novel object (T2), and in the activity cages. RESULTS: DSP-4 significantly reduced cortical and hippocampal NA levels with no effect on the hypothalamus. Isolation-reared rats exhibited locomotor hyperactivity and reduced habituation to the testing arena, although their exploration of the novel objects in T1 was not significantly different from group-reared rats. DSP-4 treatment in group-reared rats increased inner zone activity in the open field but did not significantly affect the exploration of novel objects. DSP-4 treatment in isolates reduced exploration of objects at T2 while increasing exploration of the general environment. CONCLUSIONS: Isolation rearing influences the behavioural effects of central NA depletion. The results suggest isolation-induced changes in the central noradrenergic system in the isolated rat, supporting the view that early environmental factors can have long-term effects on central noradrenergic function as well as other neurotransmitter systems. 相似文献