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41.

Ethnopharmacological relevance

The study was aimed at evaluating medicinal and therapeutic potentials of two Lycopodiaceae species, Lycopodium clavatum (L.) and Lycopodium thyoides (Humb. & Bonpl. ex Willd), both used in South American folk medicine for central nervous system conditions. Alkaloid extracts were evaluated for chemical characterization, acetylcholinesterase and antioxidant activities.

Materials and methods

The alkaloid extracts obtained by alkaline extraction were determined for each species by GC/MS examination. The evaluation of the anticholinesterase and the antioxidant activities of the extracts were tested by determining in vitro and ex vivo models. Effects on acetylcholinesterase (AChE) were tested in vitro using rat brain homogenates and ex vivo after a single administration (25, 10 and 1 mg/kg i.p.) of the alkaloid extracts in mice. The in vitro antioxidant effects were tested for the 2-deoxyribose degradation, nitric oxide (NO) interaction, 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity and total reactive antioxidant potential (TRAP). After an acute administration (25 and 10 mg/kg i.p.) of the extracts in middle-aged (12 months) mice, the antioxidant effects were estimated through the thiobarbituric acid reactive substances test (TBARS), and the antioxidant enzymes activities for catalase (CAT) and superoxide dismutase (SOD) were measured.

Results

AChE activity was inhibited in vitro by the alkaloid-enriched extracts of both Lycopodium species in a dose and time-dependent manner in rat cortex, striatum and hippocampus. A significant inhibition was also observed in areas of the brain after acute administration of extracts, as well as decreased lipid peroxidation and increased CAT activity in the cortex, hippocampus and cerebellum. A moderate antioxidant activity was observed in vitro for the extracts. Chemically, the main alkaloids found for the two species were lycopodine and acetyldihidrolycopodine.

Conclusion

This study showed that the biological properties of the folk medicinal plants Lycopodium clavatum and Lycopodium thyoides include AChE inhibitory activity and antioxidant effects, two possible mechanisms of action in Alzheimer's related processes.  相似文献   
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Pharmaceutical Research - With continuing advances in biotechnology and genetic engineering, there has been a dramatic increase in the availability of new biomacromolecules, such as peptides and...  相似文献   
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The definition of obesity is based on thresholds of body mass index associated with an increase in morbimortality. This approach is relevant at a population level but it reaches some limits as far as the individual is concerned. Advances in epidemiology, physiopathology and clinics of obesity should lead to new phenotypes and nosography of obesity included in a general framework of adipose tissue disorders  相似文献   
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Summary Spinal angiomas may be drained by a very extensive venous network and preferential channels of flow opened up over great distances. These large tortuous vessels may produce signs and symptoms which, especially in poorly documented cases, may lead to erroneous diagnoses of multifocal disease such as disseminated sclerosis. The authors describe three cases in which the venous pathways have been demonstrated extending into the cranium to involve the subtentorial and deep cerebral venous systems. They stress the necessity for carrying out late frontal and lateral cranial angiograms in those cases where ascending spinal venous channels are noted in the venous phase of spinal arteriographic examinations.Contribution of the 1st European Colloquium for Neuroradiology, September 6, 1969 Colmar  相似文献   
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We report a case of a 42 year-old female, who came to a leishmaniasis reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis lesion in the right forearm. Treatment with low-dose intramuscular meglumine antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after 28 days, although with the development of generalized eczema. After 87 days, the lesion worsened. Patient refused treatment with amphotericin B. MA was then infiltrated in the lesion, in two sessions, resulting in local eczema, with bullae formation; however, twenty days after, both the ulcer and eczema receded. Intralesional administration of MA should be used carefully when previous cutaneous hypersensitivity is detected.  相似文献   
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This study aims to describe the clinical consequences of vitamin A deficiency (VAD) in pregnant women after bariatric surgery. Included are studies on VAD during pregnancy and after bariatric surgery conducted in humans from 1993 to 2011. There are few investigations on the relationship between pregnancy and bariatric surgery and on the damage to the binomial mother–child resulting from VAD in this relationship. The high percentage of VAD in the postoperative period is a cause for concern, especially considering the function of this vitamin in certain biological moments and in moments of intense nutritional demand. This vitamin serum evaluation is recommended during the prenatal period.  相似文献   
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