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21.
The effects of ginseng total saponins (GTS) on hypoxic damage of primary cultures of astrocytes were studied. Hypoxia was created by placing cultures in an air tight chamber that was flushed with 95% N(2)/5% CO(2) for 15 min before being sealed. Cultures showed evidence of significant cell injury after 24 h of hypoxia (increased lactate dehydrogenase (LDH) content in the culture medium, cell swelling and decreased glutamate uptake and protein content). Addition of GTS (0.1, 0.3 mg/ml) to the cultures during the exposure to hypoxic conditions produced dose-dependent inhibition of the LDH efflux. GTS (0.1, 0.3 mg/ml) also produced significant inhibition of the increased cell volume of astrocytes measured by [(3)H]O-methyl-D-glucose uptake under the hypoxic conditions. Decreased glutamate uptake and protein content was inhibited by GTS. These data suggest that GTS prevents astrocytic cell injury induced by severe hypoxiain vitro. 相似文献
22.
The effect of the root ofCoptis japonica (COPT), both the dichloromethane soluble (CH2Cl2) and insoluble (H2O) fractions, on catecholamine contents and tyrosine hydroxylase (TH) activity in PC12 cells was investigated. CH2Cl2 and H2O fractions showed 21 and 53% inhibitions on dopamine content, respectively, at a concentration of 40 μg/ml in medium: the H2O fraction provided a greater inhibitory effect. The TH activity was reduced by the treatment of COPT (H2O fraction). These results suggest that COPT has an inhibitory effect on the catecholamine biosynthesis by the reduction of TH activity in PC12 cells. 相似文献
23.
Veerhuis R Janssen I De Groot CJ Van Muiswinkel FL Hack CE Eikelenboom P 《Experimental neurology》1999,160(1):289-299
Complement activation products C1q, C4c/d, and C3c/d in amyloid plaques in Alzheimer's disease probably result from direct binding and activation of C1 by amyloid beta peptides. RT-PCR and in situ hybridization studies have shown that several complement factors are produced in the brain parenchyma. In the present study, cytokines that can be detected in amyloid plaques (i.e., interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-alpha) were found to differentially stimulate the expression of C1 subcomponents, C1-Inhibitor (C1-Inh), C4, and C3, by astrocyte and microglial cell cultures derived from postmortem adult, human brain specimens and by neuroblastoma cell lines in culture. C1r and C1s were secreted at low levels by astrocytes and neuroblastoma cell lines. Exposure of cells to IL-1 alpha, IL-1 beta, TNF-alpha and to a far lesser extent IL-6, markedly upregulated C1r, C1s, and C3 production. C4 synthesis increased in response to interferon (IFN)-gamma and IL-6, whereas that of C1-Inh could be stimulated only by IFN-gamma. Thus, C1-Inh production is refractory to stimulation by plaque-associated cytokines, whereas these cytokines do stimulate C1r, C1s, and also C4 and C3 secretion by astrocytes and neuronal cells in culture. In contrast to the amyloid plaque associated cytokines IL-1 beta, IL-1 alpha, and TNF-alpha, the amyloid peptide A beta 1-42 itself did not stimulate C1r and C1s synthesis by astrocytes, microglial cells, or neuroblastoma cell lines. Microglial cells were the only cell type that constitutively expressed C1q. The ability of C1q to reassociate with newly formed C1r and C1s upon activation of C1 and subsequent inactivation by C1-Inh, may enable ongoing complement activation at sites of amyloid deposition, especially when C1-Inh is consumed and not replaced. 相似文献
24.
L-Thyroxine (T4) is commonly prescribed medication for hypothyroidism in humans and animals. Overdose has generally resulted in limited symptomatology managed with sedatives and beta-adrenergic receptor antagonists. We describe the largest acute T4 ingestion ever reported, which resulted in a profound thyrotoxicosis, resistant to treatment. A 34-y-old man ingested 900 (0.8 mg) tablets of veterinary T4 (720 mg) and was given 60 g of activated charcoal. He became lethargic on post-ingestion days 2 and 3; had vomiting, diaphoresis and insomnia on day 4; on day 5 he "looked like he had too much coffee", began "using a lot of words" and became agitated, assaultive and stopped speaking intelligibly; and on day 6 returned to the hospital combative and confused. He was diaphoretic, mydriatic, hyperreflexic, tremulous, with clear lungs and active bowel sounds, and received activated charcoal, haloperidol, diazepam, and phenobarbital, and was tracheally intubated. During hospitalization he was rehydrated, treated with propranolol and diazepam, but remained continuously tachycardic. On day 12 he became afebrile and his tachycardia resolved. Free T4 levels ranged from > 13 mcg/dL on day 6 to 1.2 mcg/dL on day 12. By discharge (day 15) he had lost 20 kilograms of body weight, but was clinically euthyroid 2 w later. This case suggests that large intentional T4 ingestions should be managed differently than current T4 overdose protocol. 相似文献
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Thomas F Hack Tom Pickles Barry D Bultz J Dean Ruether Lorna M Weir Lesley F Degner John R Mackey 《Journal of clinical oncology》2003,21(22):4138-4144
PURPOSE: Women with breast cancer were provided with an audiotape of their primary adjuvant treatment consultation, and the following patient outcomes were measured at 12 weeks postconsultation: perceived degree of information provision, audiotape satisfaction and use, communication satisfaction with oncologist, mood state, and cancer-specific quality of life. PATIENTS AND METHODS: Participants included 628 women newly diagnosed with breast cancer and 40 oncologists from six cancer centers in Canada. The patients were block randomized to one of four consultation groups: standard care control, not audiotaped; audiotaped, no audiotape given; audiotaped, patient given audiotape; and audiotaped, patient offered choice of receiving audiotape or not. RESULTS: Patients receiving the consultation audiotape had significantly better recall of having discussed side effects of treatment than patients who did not receive the audiotape. Audiotape benefit was not significantly related to patient satisfaction with communication, mood state, or quality of life at 12 weeks postconsultation, and was not significantly affected by choice of receiving the audiotape. Patients rated the audiotape intervention positively, with an average score of 83.9 of 100. CONCLUSION: Audiotape provision benefits patients by facilitating their perception of being informed about treatment side effects, but does not significantly influence patient satisfaction with communication, mood state, or quality of life. 相似文献
28.
Higher fat and energy intakes confer a survival advantage in cystic fibrosis (CF). There is a need to develop effective nutrition programmes that ensure optimal energy intake in CF.
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
Methodology:
A cross-sectional measurement of clinical characteristics and energy and fat intakes in patients attending the CF outpatients clinic of the John Hunter Hospital, Newcastle was undertaken. Twenty-nine subjects, mean age 12 years (range 4.3–20.2), completed weighed food records to determine the contribution of fat to the percentage of the recommended energy intake obtained and to document use of pancreatic enzyme replacement therapy.
Results:
Diets with a high percentage of energy derived from fat did not guarantee that individuals with CF met their energy requirements. Subjects with total fat intakes of 100 g per day or greater, however, achieved in excess of 110% recommended daily intake (RDI) for energy. Up to 47% of subjects consumed more pancreatic enzyme replacement capsules than shown to give maximum effectiveness.
Conclusion:
Setting a 100 g daily fat target is a realistic way of ensuring high energy intakes in CF. Fat ready reckoners would identify the fat content of food and prescribe specific numbers of pancreatic enzyme replacement capsules to be consumed with each meal or food item. 相似文献
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