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41.
In a previous work, the in vitro and in vivo activity of a series of diarylheptanoid derivatives against Leishmania amazonensis has been described. Based on the promising results, ten new compounds belonging to the same chemical class were synthesized and have been investigated in relation to their leishmanicidal activity. The compounds were obtained through several chemical modifications on the basic structure of curcumin (1,7-bis-(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) in an attempt to increase its effectiveness and decrease the potential toxic effects. The drugs were assayed in vitro against L. amazonensis promastigotes and using pentamidine isethionate as reference drug. The results showed that the most effective compound is 1,7-bis-(4-propargyl-3-methoxyphenyl)-1,6-heptadiene-3,5-dione, which is about ten times more efficient than the original curcumin. Nevertheless, these results did not allow us to make any correlation between the leishmanicidal activity and the chemical structure of the compounds. 相似文献
42.
Silva EP Fonseca FA Ihara SS Izar MC Lopes IL Pinto LE Badimon JJ Tuffik S Paiva TB Kasinski N de Paola AV Carvalho AC 《Journal of cardiovascular pharmacology》2002,39(3):389-395
There is little information regarding the time of hypolipidemic treatment of changes in atherosclerotic plaque, tissue cholesterol content, and also for the recovery of endothelial function. To assess the early effects of lipid-lowering treatment on these parameters, six groups of New Zealand male rabbits were studied. Animals in groups I and II were fed regular chow; groups III and IV received a 12-week 0.5% cholesterol diet followed by 12 weeks of 0.05% cholesterol diet. Finally, groups V and VI were fed a 12-week 0.5% cholesterol diet and were then shifted to a regular diet for 12 weeks. During the last four weeks, the rabbits in groups I, III, and V received low-dose pravastatin (2 mg/day), added to the diet. Group IV animals had the highest cholesterol plasma levels (vs. groups I, II, III, and V, p < 0.01) and presented atherosclerotic plaques in a more advanced stage. Nonatherogenic diet was insufficient to restore endothelial function in animals previously fed cholesterol-enriched diets (groups IV and VI). Conversely, pravastatin treatment promoted significant improvement in endothelial function and reduced the progression of atherosclerosis. Marked increase in cholesterol content was seen in aorta and liver in response to the atherogenic diet. However, neither treatment with pravastatin nor nonatherogenic diet was capable of modifying the tissue cholesterol content. Our study supports the hypothesis that the early use of statins can attenuate the progression of atherosclerosis and ameliorate endothelial function. In addition, significant changes in the tissue cholesterol pool probably need a longer period of treatment. 相似文献
43.
In this study we have determined the different signalling pathways involved in adenosine A(1)-receptor (A(1)-receptor)-dependent inhibition of contractility in rat isolated atria. N-cyclopentyladenosine (CPA) stimulation of A(1)-receptor exerts: negative inotropic response, inositol phosphates accumulation, stimulation of nitric oxide synthase (NOS), increased production of nitric oxide (NO) and cyclic GMP. Inhibitors of phospholipase C (PLC), protein kinase C (PKC), calcium/calmodulin, NOS and guanylate cyclase shifted the dose-response curve of CPA on contractility to the right. Those inhibitors also attenuated the A(1)-receptor-dependent increase in cyclic GMP and activation of NOS. These results suggest that CPA activation of A(1)-receptors exerts a negative inotropic effect associated with increased production of nitric oxide and cyclic GMP. The mechanism appears to occur secondarily to stimulation of phosphoinositide turnover via PLC activation. This, in turn, triggers cascade reactions involving calcium/calmodulin and PKC, leading to activation of NOS and soluble guanylate cyclase. 相似文献
44.
Valero N Bonilla E Pons H Chacin-Bonilla L Añez F Espina LM Medina-Leendertz S García Tamayo J 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2002,96(3):348-351
We determined the influence of melatonin (MLT) on the induction of interleukin (IL)-2, IL-1 beta, IL-4, tumour necrosis factor-alpha (TNF-alpha) and gamma interferon (IFN-gamma) on mice infected with the Venezuelan equine encephalomyelitis (VEE) virus. Levels of IFN-gamma in the MLT-treated group were significantly increased (P < 0.001) when compared with the control non-infected group from day 1 to 6 post-infection (p.i.), while in infected mice treated with 500 micrograms MLT/kg of bodyweight enhanced levels of IFN-gamma were evident from 4 to 6 days p.i. No differences were detected in the levels of IL-2 between the controls, the infected mice treated with MLT and the infected untreated group, from day 2 p.i. No changes in serum levels of IL-4 were detected. In infected mice treated with MLT, blood levels of IL-1 beta were elevated almost 10-fold from day 1 to day 6 p.i. when compared to the control, the infected and the non-infected MLT-treated mice (P < 0.001). A highly significant rise (P < 0.001) of TNF-alpha was found in infected mice treated with MLT, from day 1 to 6 p.i. when compared to the other groups. A significant rise (P < 0.001) was also evident in the infected non-MLT-treated group and a less pronounced rise in the non-infected mice treated with MLT when compared to controls. The blockade of IFN-gamma and TNF-alpha did not inhibit the protective effect of MLT but when IL-1 beta was neutralized, 100% of the infected mice died suggesting that IL-1 beta induced by MLT treatment is a target cytokine to generate an immune response against the viral infection. 相似文献
45.
OBJECTIVE: To design an instrument for measuring beliefs about the social, psychological, and physiological consequences of women's climacteric stage. MATERIAL AND METHODS: The study included 340 women affiliated to Instituto de Seguridad y Servicios Sociales para los Trabajadores del Estado (Institute for Social Services and Security for State Workers, ISSSTE) (age mean = 49.46, (SD 7.92). The mean number of pregnancies in the sample was 3.75 (SD 2.57), and the mean number of born children was 3.21 (SD 2.19); 48% of women were premenopausal, 10.9% perimenopausal, and 40.6% postmenopausal. The instrument consisted of 25 items. RESULTS: A factorial analysis with Varimax rotation was carried out. Four factors were confirmed: disadvantages (alpha = 0.769), advantages (alpha = 0.839), physiological (alpha = 0.659), and psychological (alpha = 0.711). CONCLUSION: This instrument shows good internal consistency, and measures four climacteric belief groups: a) beliefs on disadvantages, b) beliefs on advantages, c) beliefs on physiological ailments, and d) beliefs on psychological symptoms. All three confirmed dimensions of the climacteric phase have been proposed in other studies. 相似文献
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49.
IB SEWERIN 《European journal of oral sciences》1971,79(2):73-80
abstract – A study of habitual self mutilation of the buccal and/or labial mucosa by biting was conducted on 8,589 persons attending the Royal Dental College, Copenhagen. Forty-two cases were found. The youngest patient was 5 years old and the oldest was 47. The condition occurred most frequently (1.77%) among persons aged 15–19 years. There was no difference in prevalence between males and females. Combined mutilation of cheek(s) and lip(s) was more frequent (62%) than isolated mutilation of the cheek(s) (24%) or isolated mutilation of the lip(s) (14%). Bilateral biting of the cheeks was more frequent than unilateral biting, and biting of the lower lip was more frequent than biting of the upper lip. Ninety-three per cent of the patients were aware of their habit, and most of them stated that they had been biting for years. Twenty patients were re-examined; in all but one patients the biting persisted but in 7 patients the location of the lesions had changed. In several cases a link could be traced to personal problems and mental stress. It was further noticed that many patients were students and white-collar workers, suggesting that "intellectual" work may predispose for the habit. 相似文献
50.
González-Arrieta ML 《Gaceta médica de México》2004,140(2):225-227
Medicine and literature are bound humanistically disciplines from the moment that Man has the necessity to communicate his restlessness, anguish and fears with regard to the presence of illness and death. Medical topics are a frequent resource in literary works in which the writer amalgamates the patient, the doctor, illness, and death from the human point of view. Specifically in the historical quality of the novel, the author is forced nevertheless to be documented thoroughly on the topic on which his work rotate, in such a way that he avoids incorrect historical data, combined with the necessity to give flight to his imagination in the creation of fictitious situations for his narration. Here we analyze as example of the details of medicine in the Egyptian culture beginning with the novel "Sinuhé the Egyptian", as an answer to scientific commentary at an international on congress of neurosurgery. 相似文献