The incidence and prevalence of neurodegenerative diseases (ND) increase with life expectancy. This paper reviews the role of oxidative stress (OS) in ND and pharmacological attempts to fight against reactive oxygen species (ROS)-induced neurodegeneration. Several mechanisms involved in ROS generation in neurodegeneration have been proposed. Recent articles about molecular pathways involved in ROS generation were reviewed. The progress in the development of neuroprotective therapies has been hampered because it is difficult to define targets for treatment and determine what should be considered as neuroprotective. Therefore, the attention was focused on researches about pharmacological targets that could protect neurons against OS. Since it is necessary to look for genes as the ultimate controllers of all biological processes, this paper also tried to identify gerontogenes involved in OS and neurodegeneration. Since neurons depend on glial cells to survive, recent articles about the functioning of these cells in aging and ND were also reviewed. Finally, clinical trials testing potential neuroprotective agents were critically reviewed. Although several potential drugs have been screened in in vitro and in vivo models of ND, these results were not translated in benefit of patients, and disappointing results were obtained in the majority of clinical trials.
Purpose:To compare the biocompatibility of ethyl-cyanoacrylate (ECA) and octylcyanoacrylate (OCA) wound closures to sutures in rat skin. Methods: Twenty-four male Wistar rats were subjected to three incisions which were closed using ECA, OCA or sutures . Rats were divided into four groups which received biopsies on the 3 rd , 7 th , 14 th or 21 st postoperative days. Necrosis, inflammation, dermatitis, infection, dehiscence, cicatricial enlargement and costs were examined; the histopathology evaluated was epithelialization, deep openings, foreign substance reaction, residues of synthesis material, fibrosis, inflammation, dehiscence and necrosis. Results: The tissue adhesives presented the largest dehiscence levels, and ECA the lowest cost while the other measures were similar. Regarding histopathology, deep openings were more common with OCA and granulomas were most frequently obtained with ECA. The two tissue adhesives produces less inflammation than the inicial suture from post-operative day 7, while ECA and OCA cause similar inflammatory reactions. ECA did not differ significantly from OCA and sutures on other measures. Conclusion: ECA was well tolerated in this study and did not induce necrosis, allergic reactions or infections, presenting several advantages in relation to OCA and sutures, including lower costs and fewer complications. Key words: Tissue adhesives. Cyanoacrylates. Materials Testing. Rats. RESUMOObjetivo: Investigar a biocompatibilidade do etil-cianoacrilato (ECA) em fechamento de pele em ratos comparativamente ao octil-cianoacrilato (OCA) e à sutura. Métodos: Rattus norvegicus albinus (n=24) foram submetidos a três incisões, cada uma fechada por um dos métodos de síntese estudados. Quatro grupos (n=6) foram feitos, conforme o dia pós-operatório (DPO) em que foram eutanasiados: 3DPO, 7DPO,14DPO e 21DPO. Necrose, edema, eritema, dermatite, infecção, deiscência, alargamento cicatricial e custos foram os itens examinados; histopatologicamente avaliou-se epitelização, abertura profunda, reação de corpo estranho, resíduos de material de síntese, fibrose, reação inflamatória, deiscência e necrose. Resultados: Os adesivos apresentaram os maiores níveis de deiscências, e o ECA o custo mais baixo; nos demais itens, não houve diferenças. Histopatologia: A abertura profunda foi mais comum com o OCA; ECA foi o material mais encontrado em granulomas; os adesivos foram mais brandos que a sutura a partir do 7º DPO no quesito inflamação, enquanto que o ECA causou uma reação similar ao OCA; nos outros itens, ECA não apresentou diferença importante em relação ao OCA e à sutura. Conclusão: O ECA foi bem tolerado neste grupo de estudo, sem induzir necrose, reações alérgicas e infecção, apresentando diversas vantagens de uso em relação ao OCA e à sutura. Descritores: Adesivos Teciduais. Cianoacrilatos. Teste de Materiais. Ratos. -ORIGINAL ARTICLE Souza SC et al 310
Os óleos essenciais das folhas, flores e frutos de Myrcia myrtifolia DC foram coletados ao longo dos anos de 2002 e 2003 e foram analisados utilizando CG-DIC e CG-EM. No total foram identificados 28 componentes sendo que o α-pineno foi a substância predominante em todas as amostras analisadas apresentando-se em concentrações que variaram entre 61.5 e 90.9%. As propriedades antimicrobianas do óleo essencial das folhas coletadas em outubro de 2002 foram avaliadas contra seis bactérias, duas leveduras e cinco fungos filamentosos sendo mais fortemente ativo contra Microsporum canis e Trichophyton rubrum, ativo contra Staphylococcus aureus, Staphylococcus aureus resistente à meticilina, Candida albicans, Cryptococcus neoformans e Aspergillus fumigatus. O óleo ainda mostrou uma toxicidade moderada, LC 50 of 479,16 μg mL -1 , contra Artemia salina.This work reports the seasonal variation of the composition of leaf volatile oils and the composition of volatile oils from flowers and fruits of Myrcia myrtifolia DC harvested in the sand dunes of Salvador, Bahia, northeastern region of Brazil between 2002 and 2003. The oils were analyzed by GC-FID and GC-MS so that 28 components were identified. α-Pinene was predominant in a range from 61.5 to 90.9% in all samples analyzed. The leaf oil collected in October 2002 had their antimicrobial properties tested against six bacteria, two yeasts and five filamentous fungi being active against Staphylococcus aureus, methicilin-resistant Staphylococcus aureus, Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus, and showed strongest activity against Microsporum canis and Trichophyton rubrum. The oil displayed moderate toxicity against Artemia salina showing a LC 50 of 479.16 μg mL -1 .Keywords: Myrtaceae, Myrcia myrtifolia, essential oil, monoterpene, sesquiterpene, antimicrobial activity IntroductionAromatic plants have been used since ancient times as antiseptics and anti-infectious agents, as aroma in perfumes and cosmetics as well as preservative and flavour ingredients in food and beverages. Their biological properties are directly related with their chemical compositions, which can be affected by environmental, geographical, seasonal and circadian variations.The family Myrtaceae is constituted by 140 genera with about 3000 species, which are widely distributed in America and Australia. 1 The genus Myrcia comprises more than 300 species that grow in all Brazilian territory. Indigenous tribes and traditional Brazilian communities have used several species of this genus as astringent, against diabetes and diarrhea, as diuretic, to stanch hemorrhages, against the hypertension and ulcers of the mouth. 2 Some works were published regarding the chemistry and the biological properties of Myrcia species. From M. citriofolia, the occurrence of a C-methylated flavone, eucalyptin, was related, 3 from the methanolic extract of M. multiflora were isolated flavonol, flavanone and acetophenone glucosides along with myricitrin, mearnssitin, quercitrin, desmanthin-1 and guaijaverin...
Recebido em 19/8/08; aceito em 28/1/09; publicado na web em 3/7/09 SEASONAL VARIATION OF THE COMPOSITION OF ESSENTIAL OIL FROM Myrcia salzmannii Berg. (Myrtaceae). This work report the seasonal variation of composition of the volatile oils from leaves and from flowers of Myrcia salzmannii harvested in the sand dunes of Salvador, Bahia, northeastern region of Brazil in the years 2001 and 2003. The oils were analyzed by GC-FID and GC-MS being identified 49 components. Nine essential oil samples of leaves collected on different months and years and one sample of flowers were analyzed. β-Caryophyllene and α-humulene were the only compounds present in all of the samples being the first the majority compound.Keywords: Myrcia salzmannii; essential oil; terpenes. INTRODUÇÃOAs plantas aromáticas têm sido utilizadas desde a Antigüidade como antissépticos e agentes anti-infecciosos, para dar aroma a perfumes e cosméticos e como flavorizantes em alimentos e bebidas. Suas propriedades biológicas estão diretamente relacionadas com a composição química, a qual pode ser afetada pelas variações ambiental, geográfica, sazonal e circadiana.As espécies da família Myrtaceae são particularmente ricas em óleos essenciais. Essa família é constituída de 140 gêneros e aproximadamente 3000 espécies 1 com dois principais centros de desenvolvimento, a América tropical e a Austrália, embora ocorram em outras regiões no mundo.2 O gênero Myrcia é um dos maiores da família com cerca de 300 espécies e muito bem representado em todo o território brasileiro. Espécies desse gênero têm sido utilizadas na medicina popular como adstringentes, diuréticos, contra o Diabetes mellitus, para estancar hemorragias e no tratamento de hipertensão e úlceras. 3Relativamente ao seu grande número, são poucas as publicações acerca da química das espécies do gênero Myrcia. Em M. citriofolia, foi relatada a ocorrência de eucaliptina, uma flavona C-metilada.4 O extrato metanólico de M. multiflora mostrou potente atividade inibitória da aldose redutase, 5,6 uma enzima que está relacionada com algumas complicações do Diabetes mellitus. 7,8 O fracionamento desse extrato levou ao isolamento de flavanonas glicosiladas (myrciacitrinas I e II) e acetofenonas glicosiladas (myrciafenonas A e B). Os óleos essenciais de 17 espécies do gênero já foram estudados e ficou demonstrado que os sesquiterpenos foram predominantes em todos eles exceto em M. myrtifolia, 9 em que houve uma larga predominância de monoterpenos e M. acuminatissima e M. bombycina, nos quais o conteúdo de monoterpenos foi apenas ligeiramente maior que o de sesquiterpenos.
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