Avaliação in vitro da atividade de óleos essenciais sobre Candida auris / In vitro evaluation of the activity of essential oils about Candida auris

O objetivo deste trabalho foi avaliar a atividade in vitro dos óleos essenciais de Cinnamomum cassia, Eucalyptus citriodora; Eucalyptus globulus, Eugenia caryophyllus, Melaleuca alternifólia, Myristica fragans, Ocimum basilicum, Origanum majorana, Origanum vulgare, Rosamarinus officinalis, Salvia sclarea, Schinus terebinthifolius, Thymus vulgaris e Zingiber officinale, bem como dos compostos químicos desses óleos essenciais, com as menores concentrações fungicidas mínimas sobre três isolados biológicos de Candida auris de origem humana. Determinar e avaliar in vitro as concentrações fungicidas mínimas dos antifúngicos sintéticos anfotericina B, cetoconazol, flucitocina, fluconazol, itraconazol e voriconazol sobre Candida auris. Para avaliação da atividade antifúngica e obtenção da concentração fungicida mínima (CFM) utilizou-se a técnica de microdiluição em caldo, na base 2, em meio RPMI 1640, acrescido de tensoativo Tween20, e a confirmação da inibição em Agar Sabouraud dextrose, a 37ºC por 24hs. Para a avaliação da sensibilidade a anfotericina B, cetoconazol, flucitocina...(AU)

The objective of this search was to evaluate the in vitro activity of the essential oils Cinnamomum cassia, Eucalyptus citriodora; Eucalyptus globulus, Eugenia caryophyllus, Melaleuca alternifolia, Myristica fragans, Ocimum basilicum, Origanum majorana, Origanum vulgare, Rosamarinus officinalis, Salvia sclarea, Schinus terebinthifolius, Thymus vulgaris and Zingiber officinale as well as the chemical compounds of these essencial oils with the lowest minimum fungicidal concentrations on three biological isolates of Candida auris of human origin. Determine and evaluate in vitro the minimum fungicidal concentrations of the synthetic antifungals amphotericin B, ketoconazole, flucitocin, fluconazole, itraconazole and voriconazole on Candida auris. To evaluate the antifungal activity and obtain the minimum fungicidal concentration (CFM), the broth microdilution technique was used in RPMI 1640 medium, plus Tween20 surfactant, and confirmation of inhibition in Sabouraud dextrose Agar, at 37ºC for 24 hours. For the evaluation of sensitivity to amphotericin B, ketoconazole, flucitocin, fluconazole, itraconazole and voriconazole, the commercial test E-test® was used. The three isolates were resistant to the oils Myristica fragans, Shinus terebinthifolius and Zenziber officinale. The other essential oils showed inhibitory activity on Candida auris. The three isolates were more sensitive to Cinnamomum cassia essential oil, with CFM of 0.00001 µg/mL for isolate 1 and CFM of 0.10 µg/mL for isolate 2 and CFM of 0.05 µg/mL for isolate 3. Thymus vulgaris also showed lower fungicidal concentration for isolates 1 and 2, with CFM results of 684.76 µg/mL for isolate 1 and CFM of 171.19 µg/mL for isolate 2. The three biological isolates evaluated were more sensitive to cinnamic aldehyde, isoeugenol and timol, with the following results being found for isolates 1, 2 and 3 respectively: Cinnamic aldehyde - CFM 0.026µg/mL, 0.83 µg/mL and 3, 33 µg/ml; Isoeugenol CFM of 1.60 µg/ml, 1.60 µg/ml and 12.82 µg/ml; timol CFM of 2.93 µg/ml, 1.46 µg/ml and 11.74 µg/ml. The three isolates were resistant to chemical compounds: α-Humulene, ßCaryophyllene, γ-Terpinene and P-Cimene. For synthetic antifungal agents, 7 the three isolates were resistant to fluconazole and voriconazole. The MIC of amphotericin B was 0.50 µg / ml for isolates 1 and 3 and 0.75 µg / ml for isolate 2; for ketoconazole, MIC was 3 µg / ml for isolates 1 and 2 and 4 µg / ml for isolate 3; the MIC of flucitocin was 2 µg / ml for isolate 1, 1 µg / ml for isolate 2 and 1.5 µg / ml for isolate 3; for itraconazole the MIC was 4 µg / ml for the three isolates. According to the conditions of this research, the essential oils of Cinnamomum cassia, Thymus vulgaris and Origanum vulgare and the chemical compounds cinnamic aldehyde, isoeugenol and thymol showed antifungal activity with the lowest concentrations of fungicides in biological isolates of Candida auris. (AU)

Investigação dos processos biológicos associados à produção endógena de aldeídos reativos / Research on biological processes associated with endogenous production of reactive aldehydes

Os aldeídos são espécies reativas que podem ser produzidos endogenamente por processos como a lipoperoxidação, podendo reagir com lipídios, proteínas e DNA. Diversas evidências apontam para o envolvimento de aldeídos reativos na progressão de patologias como doenças cardiovasculares, arteriosclerose e doenças neurodegenerativas. Uma meta central do CEPIDRedoxoma é estudar a reatividade química de intermediários redox em ambientes biológicos e consequentes mudanças na estrutura e função de biomoléculas, entender como cada intermediário redox reage com biomoléculas específicas e os efeitos resultantes, essenciais para a concepção de biomarcadores e antioxidantes. O nosso grupo estuda os mecanismos de formação, detoxificação e reação com biomoléculas de aldeídos reativos endógenos e exógenos e seu papel em patologias como a esclerose lateral amiotrófica (ALS). Um dos mecanismos de detoxificação desses aldeídos é através da conjugação com a carnosina. Recentemente, foi observado que a suplementação de animais transgênicos ALS SOD G93A com carnosina via oral resultou em retardo da perda de peso e tendência de aumento da sobrevida dos animais. O presente projeto buscou investigar o possível papel da carnosina em animais modelo para ALS. Para isso as modificações em DNA induzidas por aldeídos reativos e a formação de adutos de carnosina-aldeídos foram analisadas através de metodologia HPLC-MS/MS. Assim observamos que ratos suplementados com carnosina apresentaram níveis significativamente menores de proteína carbonilada em músculo e fígado. Em fígadoforam vistos níveis menores de dois adutos de DNA, 8-oxodGuo e1,N2-HO-propanodGuo, em animais suplementados. Em cérebro foram detectados níveis menores de 1, N2-εdGuo. Com relação aos adutos carnosina-aldeídos, foi observado níveis significativamente maiores do aduto CAR-HHE na medula. Com embasamento nos resultados aqui apresentados, sugere-se a utilização de sequestradores de aldeídos como uma estratégia terapêutica em condições fisiopatológicas nas quais ao acúmulo dessas espécies está comprovado

Aldehydes are reactive species that can be produced endogenously by processes such as lipid peroxidation, which can react with lipids, proteins and DNA. Several evidences point to the involvement of reactive aldehydes in the progression of pathologies such as cardiovascular diseases, atherosclerosis and neurodegenerative diseases. A central goal of CEPID-Redoxoma is to study the chemical reactivity of redox intermediates in biological environments and consequent changes in the structure and function of biomolecules, to understand how each redox intermediate reacts with specific biomolecules and the resulting effects, essential for the design of biomarkers and antioxidants. Our group studies the mechanisms of formation, detoxification and reaction with biomolecules of endogenous and exogenous reactive aldehydes and their role in pathologies such as amyotrophic lateral sclerosis (ALS). One of the detoxification mechanisms of these aldehydes is through carnosine conjugation. Recently, we observed that oral carnosine supplementation in transgenic ALS SODG93A animals resulted in delayed weight loss and a tendency to increase the survival of the animals. The present project investigated the potential role of carnosine in animal models for ALS. Thus, reactive aldehydes induced DNA modifications and carnosine aldehyde adducts were analyzed by HPLC-MS/MS. We observed that rats supplemented with carnosine presented significantly lower levels of protein carbonylation in muscle and liver. Lower levels of two DNA adducts, 8-oxodGuo and 1, N2-HO-propanodGuo, were observed in liver of the supplemented animals. Lower levels of 1, N2-εdGuo were detected in the brain. Regarding the carnosine-aldehydeadducts, significantly higher levels of the CAR-HHE adduct were observed in spinal cord. The results presented here suggest the use of aldehyde scavengers as a therapeutic strategy under pathological conditions in which is proven the accumulation of these species

Aumento de estresse oxidativo no sangue de pacientes com ostomia / Increased oxidative stress in the blood of ostomy patients

ABSTRACT BACKGROUND: Ostomy is a surgical procedure that creates a stoma that aims to construct a new path for the output of feces or urine. The relationship of oxidative stress (OxS) markers in patients with ostomy is still poorly described. OBJECTIVE: The present study was aimed at investigating the changes in oxidative stress parameters in peripheral blood collected from ostomy patients when compared with a healthy control group. METHODS: It was evaluated 29 ostomy patients and 30 healthy control patients. The oxidative stress parameters evaluated were: lipid peroxidation [lipid hydroperoxide (LPO), 8-isoprostane (8-ISO) and 4-hydroxynonenal (4-HNE)], protein oxidation and nitration [carbonyl and 3-nitrotyrosine (3-NT)] and DNA oxidation [8-hydroxy-2'-deoxyguanosine (8-OHDG)] in serum from ostomy patients compared to health controls. RESULTS: The data showed an increase of LPO, 8-ISO, 4-HNE, 3-NT and 8-OHDG in serum collected from ostomy patients when compared to healthy controls. CONCLUSION: The findings support the hypothesis that ostomy triggers the oxidative stress observed in the blood collected from these patients.

RESUMO CONTEXTO: Ostomia é um procedimento cirúrgico que cria um estoma com objetivo de construir um novo caminho para a saída das fezes ou urina. A relação dos marcadores de estresse oxidativo em pacientes ostomizados ainda é pouco descrita. OBJETIVO: O presente estudo tem como objetivo investigar as alterações dos parâmetros de estresse oxidativo em sangue de pacientes ostomizados comparados a controles saudáveis. MÉTODOS: Foram avaliados 29 pacientes ostomizados e 30 controles saudáveis. Os parâmetros de estresse oxidativo avaliados foram: peroxidação lipídica [hidroperóxido de lipídio (LPO), 8-isoprostano (8-ISO) e 4-hidroxinonenal (4-HNE)], oxidação e nitração de proteínas [carbonila e 3-nitrotirosina (3-NT)] e oxidação do DNA [8-hidroxi-2'-desoxiguanosina (8-OHDG)] em soro de pacientes ostomizados comparados a controles saudáveis. RESULTADOS: Os dados mostraram um aumento de LPO, 8-ISO, 4-HNE, 3-NT e 8-OHDG em soro de pacientes ostomizados em comparação a controles saudáveis. CONCLUSÃO: Os achados sustentam a hipótese de que a ostomia desencadeia o estresse oxidativo observado no sangue coletado destes pacientes.

Efeito de aldeídos de colesterol na esclerose lateral amiotrófica: estudo em modelo animal e na agregação da SOD1 in vitro / Effect of secosterol aldehydes on Amyotrophic Lateral Sclerosis: study in animal model and SOD1 aggregation in vitro

Aldeídos de colesterol (Secosterol A e Secosterol B) têm sido detectados em amostras de cérebro humano e investigados em modelos de doenças neurodegenerativas como possíveis marcadores e intermediários do processo patológico. Estes oxisteróis constituem uma classe de eletrófilos derivados de lipídeos que podem modificar e induzir agregação de proteínas. A esclerose lateral amiotrófica (ELA) é um distúrbio neurodegenerativo associado ao acúmulo de agregados imunorreativos de superóxido dismutase (Cu, Zn-SOD, SOD1). O objetivo deste trabalho foi avaliar a presença de aldeídos de colesterol em ratos modelo ELA e sua capacidade de induzir a formação de agregados de SOD1 in vitro. Aldeídos de colesterol foram analisados no plasma, medula espinhal e córtex motor de ratos ELA. Uma quantidade elevada de Secosterol B foi detectada no córtex motor desses ratos em comparação com animais controle. Adicionalmente, os experimentos in vitro mostraram que Secosterol B e Secosterol A induziram a agregação da SOD1 em uma forma amiloidogênica que se liga à tioflavina T. Esta agregação não foi observada com o colesterol e os seus hidroperóxidos. Usando aldeídos de colesterol marcados com grupo alquinil e um ensaio de click chemistry, foi observado que os agregados de SOD1 estão ligados covalentemente aos aldeídos. A modificação covalente da proteína foi confirmada por análise de MALDI-TOF, que mostrou a adição de até cinco moléculas de aldeídos de colesterol à proteína por base de Schiff. Curiosamente, a análise comparativa com outros eletrófilos derivados de lipídeos (e.g. HHE e HNE) demonstrou que a agregação de SOD1 aumentou proporcionalmente à hidrofobicidade dos aldeídos, observando-se a maioragregação com aldeídos de colesterol. Os sítios de modificação da SOD1 foram caracterizados por nanoLC-MS/MS após digestão da proteína com tripsina, onde foram identificadas lisinas como o principal aminoácido modificado. Em geral, nossos dados mostram que a oxidação do colesterol que leva à produção de aldeídos de colesterol é aumentada no cérebro de ratos ELA e que os aldeídos altamente hidrofóbicos derivados de colesterol podem promover eficientemente modificação e agregação de SOD1

Secosterol aldehydes (Secosterol B and Secosterol A) have been detected in human brain samples and investigated in models of neurodegenerative diseases as possible markers and intermediates of the pathological process. These oxysterols constitute a class of lipid-derived electrophiles that can modify and induce aggregation of proteins. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder associated with the accumulation of immunoreactive aggregates of superoxide dismutase (Cu, Zn-SOD, SOD1). The objective of this work is to evaluate the presence of secosterol aldehydes in ALS rats and their ability to induce formation of SOD1 aggregates in vitro. Secosterol aldehydes were analyzed in plasma, spinal cord and motor cortex of ALS rats. A higher amount of Secosterol B was detected in the motor cortex of these rats compared to control animals. In addition, in vitro experiments have shown that Secosterol B and Secosterol A induce aggregation of SOD1 into an amyloidogenic form that binds to thioflavin T. This aggregation was not apparent in incubations with cholesterol and its hydroperoxides. Using alkynyl-labeled secosterol aldehydes and a click chemistry assay, it was found that the SOD1 aggregates are covalently linked to the aldehydes. Covalent modification of the protein was confirmed by MALDI-TOF analysis, which showed the addition of up to five molecules of secosterol aldehydes to the protein by Schiff base formation. Interestingly, the comparative analysis with other lipid-derived electrophiles (e.g. HHE and HNE) demonstrated that the aggregation of SOD1 increased according to the hydrophobicity of the aldehydes. Compared to the other electrophiles, a higher SOD1 aggregation was observed with secosterol aldehydes. SOD1 modification sites were characterized by nanoLC-MS/MS afterprotein digestion with trypsin, revealing lysine as the major amino acid modified in these experiments. Collectively, our data show that cholesterol oxidation leads to the production of secosterol aldehydes, which are increased in the brain of ALS rats, and that these highly hydrophobic aldehydes can efficiently promote the modification and aggregation of SOD1

Insights into the intracellular mechanisms of citronellal in Candida albicans: implications for reactive oxygen species-mediated necrosis, mitochondrial dysfunction, and DNA damage

Abstract INTRODUCTION Citronellal (Cit) possesses antifungal activity and has possible implications for reactive oxygen species (ROS) generation in Candida albicans. In this study, the effects of Cit on ROS generation and the mechanisms by which Cit exerts anti-Candida effects were examined. METHODS A 2′,7′-dichlorodihydrofluorescein diacetate assay was used to assess oxidative damage. Cell necrosis was determined by flow cytometry after FITC-Annexin V staining. Mitochondrial function was studied based on mitochondrial potential, metabolic activity (MTT assay), and phenotypic susceptibility on a non-fermentable carbon source. Membrane intactness and DNA damage were estimated by a propidium iodide (PI) uptake assay and 4',6-diamidino-2-phenylindole (DAPI) staining. RESULTS ROS generation was enhanced in response to Cit, leading to necrosis (2%). Additional hallmarks of cell death in response to Cit, such as mitochondrial membrane depolarization and DNA damage, were also observed. Cit treatment resulted in dysfunctional mitochondria, as evidenced by poor labeling with the mitochondrial membrane potential-sensitive probe rhodamine B, reduced metabolic activity (61.5%), and inhibited growth on a non-fermentable carbon source. Furthermore, Cit induced DNA damage based on DAPI staining. These phenotypes were reinforced by RT-PCR showing differences in gene expression (30-60%) between control and Cit-treated cells. Finally, PI uptake in the presence of sodium azide confirmed non-intact membranes and suggested that Cit activity is independent of the energy status of the cell. CONCLUSIONS Cit possesses dual anticandidal mechanisms, including membrane-disruptive and oxidative damage. Taken together, our data demonstrated that cit could be used as a prominent antifungal drug.

Modificações em proteínas induzidas por compostos eletrofílicos. possível papel em esclerose lateral amiotrófica / Modifications in proteins induced by electrophilic compounds. Possible role in amyotrophic lateral

Danos em biomoléculas podem ocorrer a partir de uma interação direta entre as biomoléculas e espécies reativas de oxigênio e nitrogênio como também, pela reação de produtos secundários dessas espécies como eletrófilos gerados na peroxidação lipídica. Alguns desses produtos secundários possuem estabilidade química maior que as espécies reativas das quais foram derivadas e podem se ligar covalentemente as biomoléculas comprometendo o funcionamento normal das mesmas. Portanto, modificações em proteínas por aldeídos gerados na lipoperoxidação têm sido investigadas por suas implicações com desordens patológicas relacionadas à agregação proteica, e modificações em diversas vias de sinalização amplificando os efeitos deletérios em sistemas biológicos. Os objetivos desse trabalho foi contribuir na elucidação dos mecanismos moleculares associados ao desenvolvimento da esclerose lateral amiotrófica (ELA) através da identificação, caracterização e quantificação de modificações póstraducionais em proteínas pelos aldeídos 4-hidroxi-2-hexenal (HHE) e trans-4-hidroxi-2-nonenal (HNE) in vitro (citocromo c) e in vivo (modelo ELA) a partir de técnicas de Western blot, imunoprecipitação e espectrometria de massa com abordagem proteômica de "shotgun" em ratosSOD1G93A modelo de esclerose lateral amiotrófica (ELA). Estudos com citocromo c mostraram a ligação dos aldeídos ao citocromo c e mecanismos de reação foram propostos. Foram encontrados seis peptídeos modificados por HHE e um para o HNE, e o peptídeo TGPNLHGLFGR se mostrou modificado pelos dois aldeídos paralelamente. Foi demonstrado que a histidina 33 é um "hot spot" frente as adições pelos aldeídos. Nas análises por western blot das proteínas ligadas a aldeídos foi possível observar uma tendência de aumento na concentração de proteínas ligadas ao HNE nos animais ELA, mais acentuada nas amostras de 70 dias comparadas ao controle. Com relação aos resultados obtidos com HHE tanto os animais pré-sintomáticos quanto os sintomáticos não apresentaram diferenças de HHE-proteína, tantonos controles quanto nos animais ELA. Nas amostras dos animais sintomáticos não detectamos diferença significativa na concentração de aldeído-proteína entre os grupos. Já as análises proteômicas revelaram 24 proteínas diferencialmente expressas, com destaque para proteínas com os maiores valores de significância (p-value), como a ubiquitina no grupo dos pré- sintomáticos e a neurogranina, no grupo dos animais sintomáticos e várias proteínas de metabolismo energético, de neurofilamentos, proteínas de processos redox e proteínas ligadas o metabolismo de cálcio (fundamentais na fisiopatologia em ELA). Algumas proteínas importantes foram encontradas com exclusividades nos grupos pré-sintomáticos e sintomáticos pelo diagrama de Venn. Com relação a proteínas modificadas pelos aldeídos, foram encontradas algumas relevantes como a proteína 2 de interação com a polimerase delta que foi modificada por HNE via adição de Michael encontrada nos animais ELA pré-sintomáticos e sintomáticos, a catalase que foi encontrada modificada por HNE via base de Schiff apenas nos ELA pré- sintomáticos, e a tiol redutase induzível por interferon gama no grupo dos animais ELA sintomáticos. Com relação a proteínas modificadas por HHE, foram encontradas a Janus quinase e proteína 3 de interação com microtúbulo, modificadas tanto por adição de Michael quanto via base de Schiff nos animais ELA sintomáticos. É interessante ressaltar que algumas modificações encontradas em proteínas não caracterizadas podem indicar proteínas novas ainda não descritas como modificadas por esses aldeídos. Os resultados mostram que algumas das proteínas modificadas por HNE e HHE encontradas neste trabalho, estão relacionadas ao estresse redox, vias metabólicas energéticas, proteínas envolvidas na resposta a danos oxidativos, e processos inflamatórios. Tais modificações ocorrem não só no modelo de neurodegeneração, mas foram previamente descritas em outros processos patológicos, como doença cardiovascular, lesão hepática por uso crônico de álcool

Damage to biomolecules can occur from a direct interaction between biomolecules and reactive of oxygen and nitrogen species as well as from the reaction of secondary products of these species as electrophiles generated in lipid peroxidation. Some of these by-products have greater chemical stability than the derived reactive species and can bind to biomolecules compromising their normal function. Therefore, protein modifications by aldehydes generated during lipoperoxidation have been investigated for their implications with pathological disorders related to protein aggregation and modifications in signaling pathways amplifying the deleterious effects in biological systems. The aim of this work was to contribute to the elucidation of the molecular mechanisms associated with the development of amyotrophic lateral sclerosis (ALS) through the identification, characterization and quantification of posttranslational modifications in proteins by 4-hydroxy-2-hexenal (HHE) and trans-4-hydroxy-2- nonenal (HNE) in vitro, cytochrome c, and in vivo, rat model (SOD1G93A) of amyotrophic lateral sclerosis (ALS), throught Western blot techniques, and mass spectrometry with shotgun proteomics approach. The results showed the binding of aldehydes to cytochrome c. Six peptides were modified by HHE and one by HNE. The peptide TGPNLHGLFGR was modified by the two aldehydes. Histidine 33 has been shown to be a hot spot against aldehydes additions. By western blot analysis of the aldehyde-bound proteins, it was possible to observe a tendency of increase in the concentration of HNE-bound proteins in the ALS animals, more pronounced in the samples of 70 days compared to control samples. Regarding the results obtained with HHE, both pre-symptomatic and symptomatic animals did not show HHE-protein differences, both in controls and in ALS animals. We did not detect a significant difference in the aldehyde-protein concentration between the groups in the samples of the symptomatic animals. Proteomic analysis revealed 24 differentially expressed proteins, with emphasis on proteins with thehighest values of significance (p-value), such as the ubiquitin in the pre-symptomatic group and neurogranin in the group of the symptomatic animals and several proteins of the energetic metabolism pathways, neurofilaments, proteins of redox processes and proteins linked to calcium metabolism (fundamental in the pathophysiology of ALS). Some important proteins were found exclusivity in the pre-symptomatic and symptomatic groups by the Venn diagram. With regard to aldehyde-modified proteins, some relevant ones such as Delta-2 polymerase interaction protein, that was modified by HNE via the addition of Michael found in presymptomatic and symptomatic ELA animals, catalase that was found to be modified by HNE via Schiff's base only in pre-symptomatic ALS, and gamma interferon-inducible thiol reductase in the group of symptomatic ALS animals. Janus kinase and microtubule interaction protein 3, were found to be modified by Michael addition and Schiff base pathway respectively in symptomatic ALS animals. It is interesting to note that some modifications found in uncharacterized proteins may indicate new proteins not yet described as modified by these aldehydes. The results show that some of the proteins modified by HNE and HHE found in this work are related to redox stress, energetic metabolic pathways, proteins involved in the response to oxidative damage, and inflammatory processes. Such modifications occur not only in the neurodegeneration model, but were previously described in other pathological processes, such as cardiovascular disease, liver injury due to chronic alcohol use

Citronellal-induced disruption of membrane homeostasis in candida albicans and attenuation of its virulence attributes

Abstract: INTRODUCTION There is an increasing burden of multidrug resistance. As a result, deciphering the mechanisms of action of natural compounds with antifungal activity has gained considerable prominence. We aimed to elucidate the probable mechanism of action of citronellal, a monoterpenoid found in the essential oil extracted from Cymbopogon plants, against Candida albicans. METHODS Drug susceptibility was measured by broth microdilution and spot assays. Ergosterol levels were estimated using the alcoholic potassium hydroxide method and H+ extrusion was assessed by monitoring the glucose-induced acidification of the external medium. Virulence traits were studied by hyphal morphogenesis and biofilm formation, along with fungal cell adherence to polystyrene surface and human oral epithelial cells. RESULTS Citronellal showed anticandidal activity against C. albicans and non-albicans species of Candida at a minimum inhibitory concentration of 1 mg/ml. Citronellal interfered with membrane homeostasis, which is the major target of known antifungal drugs, by increasing the hypersensitivity of the fungi to membrane-perturbing agents, reducing ergosterol levels, and diminishing glucose-induced H+ extrusion. In addition, oxidative and genotoxic stresses were induced via an increased production of reactive oxygen species. Furthermore, citronellal inhibited the virulent attributes of yeast-to-hypha transition and biofilm formation. It also reduced cell adherence to polystyrene surface and the human oral epithelial cells. CONCLUSIONS This is the first study to propose the cell membrane, morphogenetic switching, biofilm formation, and cell adherence of Candida albicans as potential targets for the anticandidal activity of citronellal. However, clinical investigations on the therapeutic applications of citronellal are required.

Suicide attempts among children and adolescents: partial or total injury? / Tentativa de suicídio infanto-juvenil: lesão da parte ou do todo?

This study sought to verify the records on file and the number of cases of attempted suicide among children and adolescents who were attended by Emergency Care health professionals in the municipality of Matozinhos, Minas Gerais, Brazil. Documentary and descriptive research was conducted, the data for which was collected by means of an investigation of Outpatient Records from 2008 to 2010. Of the 73,000 files evaluated, those dealing with cases of attempted suicide among children and adolescents between the age of 3 and 18 years were selected. It was revealed that the health professionals, particularly physicians and nurses, fail to register the cases appropriately, invalidating information about the problem and potential prevention measures. The conclusion reached was that underreporting and the discrepancy of the diagnoses which were not duly referred to the competent agencies require rethinking and reviewing medical practices, and taking a systematic and careful look to address the individual as a complex whole.

Neste estudo procurou-se verificar o registro e o número de casos de tentativa de suicídio entre crianças e adolescentes do município de Matozinhos, Minas Gerais, Brasil, que foram atendidos pelos profissionais de saúde do Pronto-Atendimento. Trata-se de uma pesquisa documental e descritiva, cuja coleta dos dados ocorreu por meio de investigação nas Fichas Ambulatoriais, no período de 2008 a 2010. Das 73.000 fichas levantadas, selecionaram-se aquelas que tratavam de casos de tentativa de suicídio entre crianças e adolescentes do município, com idades entre três e 18 anos. Percebeu-se que os profissionais de saúde, mais especificamente os médicos e enfermeiros, não registram os casos de forma adequada, inviabilizando a informação sobre o problema e as medidas de prevenção. Concluiu-se que a subnotificação, a discrepância dos diagnósticos e o não encaminhamento aos órgãos competentes exigem repensar e rever a prática médica e dirigir um olhar sistematizado e cuidadoso para perceber o sujeito como um todo complexo.

Serological detection of Toxoplasma gondii, Leishmania infantum and Neospora caninum in cats from an area endemic for leishmaniasis in Brazil / Detecção sorológica de Toxoplasma gondii, Leishmania infantum e Neospora caninum em gatos de uma área endêmica para leishmaniose no Brasil

An investigation was made into the occurrence of antibodies to Toxoplasma gondii, Leishmania infantum and Neospora caninum in 151 domestic cats, based on the indirect fluorescent antibody test (IFAT). Serum samples were collected from 151 domestic cats (65 free-roaming and 86 domiciled cats; 55 males and 96 females) in Campo Grande, Mato Grosso do Sul, Brazil between January and April 2013. IgG antibodies to T. gondii, L. infantum and N. caninum were found, respectively, in 49 (32.5%), 34 (22.5%) and 10 (6.6%) sampled cats. A positive correlation was found between T. gondii and N. caninum, T. gondii and L. infantum, and N. caninum and L. infantum (p <0.05) infections. Also, a significant interaction was identified between gender and area of activity on the probability of T. gondii (p = 0.0324) infection. However, no significant interaction was observed between gender and area of activity on infections by either N. caninum or L. infantum. This study showed that cats from an area endemic for visceral leishmaniasis in Brazil are exposed to three different protozoans, two of which are causal agents of important zoonosis.

O presente estudo teve como objetivo investigar a ocorrência de anticorpos anti-Toxoplasma gondii, Leishmania infantum e Neospora caninum, em 151 gatos, por meio da Reação de Imunofluorescência Indireta (RIFI). Entre os meses de janeiro e abril de 2013, amostras de soro foram coletadas de 151 gatos domésticos (65 gatos errantes e 86 gatos domiciliados; 55 machos e 96 fêmeas), de Campo Grande, Mato Grosso do Sul, Brasil. Anticorpos IgG anti-T. gondii, anti-L. infantum e anti-N. caninum foram encontrados em 49 (32,5%), 34 (22,5%) e 10 (6,6%) gatos amostrados, respectivamente. Verificou-se uma associação estatisticamente significativa entre as infecções por T. gondii e N. caninum, T. gondii e L. infantum e N. caninum e Leishmania infantum (p <0,05). Além disso, foi observada uma interação significativa entre sexo, área de atividade na probabilidade de infecção por T. gondii (p = 0,0324). No entanto, não foi observada interação significativa entre sexo e área de atividade nas infecções por N. caninum e L. infantum. Este estudo mostrou que os gatos de uma área endêmica brasileira para leishmaniose visceral são expostos a três diferentes protozoários, sendo dois deles importantes agentes zoonóticos.

Investigação de potenciais biomarcadores redox - um enfoque em aldeídos e seus produtos / Potential redox biomarkers investigation - focus on aldehydes and their products

As espécies reativas são associadas a processos toxicológicos e fisiopatológicos, agindo como importantes mediadores, por exemplo, na sinalização celular. Diversas classes de compostos têm sido utilizadas como possíveis biomarcadores de estresse redox, destacando-se os aldeídos α,ß-insaturados, capazes de alquilar biomoléculas como o DNA. Para evitar efeitos deletérios, estes aldeídos são detoxificados por glutationilação e posterior metabolização a derivados mercaptúricos. Contudo, avaliar o estado redox em sistemas biológicos ainda é tarefa bastante complexa, sendo a dificuldade em quantificar de forma prática e acurada os efeitos de sinalização e/ou dano molecular o maior problema dos estudos redox. Assim, o objetivo deste trabalho foi desenvolver métodos acurados e sensíveis de análise de potenciais biomarcadores de estresse redox, isto é: nucleosídeos modificados, aldeídos endógenos e exógenos, glutationa e produtos de glutationilação, e avaliá-los em sistemas modelos, celular e animal, e em humanos. A avaliação dos níveis urinários de três nucleosídeos modificados por metodologia de HPLC-MS/MS desenvolvida pelo grupo em moradores da cidade de São Paulo - região com poluição atmosférica - demonstrou aumento significativo de 1,N2-propanodGuo comparado aos moradores de região não poluída. Ademais, comprova-se pela primeira vez que células deficientes em reparo de ligações cruzadas apresentam níveis basais elevados de 1,N2-propanodGuo, em duas linhagens independentes, colocando este aduto como potencial mediador de carcinogênese em pacientes portadores de Anemia de Fanconi. Utilizando cérebro de ratos SOD1G93A (modelo de Esclerose Lateral Amiotrófica - ELA), verificou-se aumento de 50% nos níveis de 1,N2-propanodGuo e de 100% nos de 1,N6-εdAdo em fase sintomática, sugerindo influência do conteúdo lipídico cerebral, levando a comprometimento do metabolismo neuronal e morte celular. O perfil de aldeídos determinado em cérebro de ratos SOD1G93A demonstrou aumento de trans-hexa-2-enal e trans,trans-hexa-2,4-dienal em fase assintomática e de trans,trans-deca-2,4-dienal em fase sintomática, não sendo observada nenhuma alteração na medula. Conhecer estas variações permite direcionar estudos de modificações em biomoléculas, além de a metodologia per se corroborar com as áreas de análises lipidômicas. Técnicas distintas e o preparo de amostras refletiram nos níveis de glutationa reduzida (GSH) e oxidada (GSSG) relatados. A técnica de espectrometria de massas mostrou-se mais precisa que a detecção eletroquímica; e a alquilação do grupo tiol minimizou interferências de matriz. Por análise de HPLC-UV/Vis-ESI-MS/MS, a quantificação de trans-4-hidroxi-2-nonenal (HNE) e crotonaldeido conjugados com GSH demonstrou não haver alterações em cérebro e medula de ratos SOD1G93A. Contudo, há formação esteroespecífica dos adutos de HNE in vivo. Ressalta-se que a metodologia desenvolvida é extremamente sensível e específica e permite análise simultânea de GSH, GSSG, cisteína, cistina e dos adutos supracitados, servindo para análise de outros adutos de glutationilação de aldeídos que possam ser importantes em doenças associadas a estresse redox

Free radicais and oxidant species are associated with toxicological and pathophysiological processes. It has been demonstrated that production of reactive oxygen species may be involved in cell signaling and regulation. Several biomarkers of redox processes have been used, including adducts formed through the reaction of α,ß-unsaturated aldehydes with biomolecules such as DNA. In order to avoid these deleterious effects, aldehydes are detoxified through glutathionylation and further metabolized to mercapturic derivatives. However, assessing the redox status in biological systems is still a very complex task, and the difficulty in practical and accurate quantification of signaling effects and/or molecular damage is a major problem in redox studies. The objective of this work was to develop accurate and sensitive methods for analysis of potential biomarkers of redox stress, i.e., modified nucleosides, endogenous and exogenous aldehydes, glutathione and glutathionylation products, and their evaluation in cell, animal model and humans. Evaluation of urinary levels of 1,N2-propano-2'-deoxyguanosine (1,N2-propanodGuo), 1,N2-etheno-2'-deoxyguanosine and 8-oxo-7,8-dihydro-2'-deoxyguanosine in residents of São Paulo City - polluted region - showed a significant increase (p<0.05) in 1,N2-propanodGuo levels compared to residents of an unpolluted region by a HPLC-MS/MS methodology developed by the group. Moreover, it was proven, for the first time, that repair deficient cells have basal levels of 1,N2-propanodGuo higher than proficient cells in two independent strains, placing 1,N2-propanodGuo as a potential mediator of carcinogenesis in Fanconi Anemia patients. In an Amyotrophic Lateral Sclerosis (ALS) animal model (SOD1G93A rat) , a 50% increase in the levels of 1,N2-propanodGuo and 100% in the 1,N6-etheno-2'-deoxyadenosine in brain tissue in the symptomatic phase was observed, suggesting that the high brain lipid content may play a role, leading to impairment of cell metabolism and neuronal cell death. There is an increase of trans-hex-2-enal and trans,trans-hexa-2,4-dienal in asymptomatic SOD1G93A rats brain and of trans,trans-deca-2,4-dienal in symptomatic ones. However, no alteration was observed in spinal cord. Our approach contributes to a better understanding of the aldehyde status in vivo and allows us to predict biomolecule modifications. The developed methodology can contribute to lipidomic studies. The use of different techniques and sample preparation reflected in the reported levels of reduced (GSH) and oxidized glutathione (GSSG). The mass spectrometry technique proved to be more accurate than the electrochemical one, and the use of thiol alkylating agent minimizes matrix interference. No changes were observed in the levels of the GSH conjugates of trans-4-hydroxy-2-nonenal (HNE) and crotonaldehyde in brain and spinal cord of SOD1G93A rats quantified by HPLC-UV/Vis-ESI-MS/MS compared to controls. However, it was observed stereospecific HNE adducts formation in vivo. Note that this methodology is extremely sensitive and specific and allows simultaneous analysis of GSH, GSSG, Cys, cystine and the aforementioned adducts, serving for analysis of other aldehyde-glutathionylation adducts that may be important in pathologies associated with stress redox

Modificação de proteínas por produtos de oxidação do colesterol: mecanismos e implicações biológicas / Modification of proteins by oxidation products of cholesterol: mechanisms and biological implications

O colesterol é um importante componente das membranas celulares em eucariotos superiores, desempenhando papéis estruturais e funcionais. O colesterol possui uma insaturação em sua estrutura sendo, portanto, alvo de oxidação mediada por espécies reativas de oxigênio e/ou nitrogênio. A oxidação não enzimática do colesterol gera, como produtos primários, os hidroperóxidos de colesterol. Tais moléculas, por sua vez, são altamente reativas e podem reagir com metais livres e/ou metaloproteínas, trazendo consequências à celula. Neste sentido, o primeiro capítulo deste trabalho tem como objetivo estudar a reação dos hidroperóxidos de colesterol (ChOOH) com o citocromo c (citc), uma heme proteína envolvida no transporte de elétrons na mitocôndria. Análises de espectroscopia no UV-Vis mostraram que o ChOOH promove o bleaching da banda Soret do citc de uma maneira dose-dependente. Mais ainda, esta reação leva à formação de radicais centrados em carbono tanto na proteína como no lipídeo, sugerindo uma redução homolítica do ChOOH. Como consequências, pode-se observar a oligomerização do citc, um processo que pode influenciar no transporte de elétrons bem como na sinalização para a apoptose. A partir da reação do citc com ChOOH podem surgir, direta ou indiretamente, outras espécies reativas, como aldeídos, cetonas e epóxidos. Dentre estas, destacam-se os aldeídos de colesterol, em particular o colesterol secoaldeído (CSec) e o carboxialdeído (ChAld), uma vez que foram encontrados elevados em placas ateroscleróticas e em tecidos cerebrais de pacientes com doenças neurodegenerativas. Tais espécies podem reagir com resíduos de aminoácidos provocando alterações estruturais e funcionais em proteínas. Neste sentido, o segundo capítulo deste trabalho tem como objetivo estudar a reação do ChAld com citc. Usando modelos mimétivos de membrana e espectrometria de massas, foi mostrado que o ChAld modifica covalentemente o citc por um mecanismo consistente com a formação de bases de Schiff. Tal modificação ocorre preferencialmente em resíduos de lisina que interagem com a membrana. Estas modificações influenciam na afinidade do citc pela membrana, aumentando sua aderência, o que pode ter influência no transporte de elétrons e sinalização para a apoptose. No terceiro e último capítulo deste trabalho nós buscamos uma ferramente analítica que permitisse analisar modificação de proteínas promovidas por produtos de oxidação de colesterol e outros esteróis. Em um estudo realizado em colaboração com o grupo do professor Porter na Universidade de Vanderbilt, utilizamos ensaios baseados em click chemistry para buscar proteínas modificadas. Para isso, foram sintetizados derivados de colesterol e 7-deidrocolesterol (7-DHC, precursor imediato do colesterol) contendo um grupo alquinil na sua cadeia lateral. Este grupo pode ser ligado a um grupo azida por meio de uma reação de cicloadição, em um processo conhecido como click chemistry. Após a síntese e caracterização dos derivados lipídicos contendo o grupo alquinil na cadeia lateral, células Neuro2a foram tratadas com o alquinil-7-DHC e o alquinil-colesterol para averiguar seu metabolismo. Análises por HPLC-MS/MS mostraram que ambos derivados contendo o grupo alquinil foram metabolisados e convertdos nos respectivos ésteres. Usando um modelo celular para a doença conhecida como Sindrome de Smith-Lemli-Opitz (SLOS), doença caracterizada pela deficiência na enzima 7-deidrocolesterol redutase, foi mostrado que o acúmulo característico de 7-DHC nos pacientes pode levar a uma maior modificação de proteínas promovidas por seus derivados, o que pode contribuir para o desenvolvimento da doença

Cholesterol is an important component of eukaryotic cellular membranes, where it has an influence in the fluidity and stability. Due to the presence of a double bond in its structure, cholesterol can be oxidized by reactive oxygen and nitrogen species. This non-enzymatic oxidation generates, as primary products, cholesterol hydroperoxides. Such molecules, in turn, are highly reactive and can react with free metal ions and/or metalloproteins, affecting cell metabolism. Therefore, the first chapter of the present study aims to investigate the reaction of cholesterol hydroperoxides (ChOOH) with cytochrome c (cytc), a heme protein involved in the mitochondrial electron transport. Spectroscopic analyses in the UV-Vis region showed that ChOOH induces a dose-dependent bleaching of cytc's Soret band. In addition, this reaction leads to the formation of carbon-centered radicals on both protein and lipid, suggesting a homolytic reduction of ChOOH. As consequences, cytc undergoes oligomerization, a process that can influence electron transport and apoptosis signaling. The reaction of cytc and ChOOH can produce, directly or indirectly, reactive species such as epoxides, aldehydes and ketones. Among them, cholesterol aldehydes, such as cholesterol secoaldehyde (CSec) and cholesterol carboxyaldehyde (ChAld), are of particular interest, since they were previously found elevated in atherosclerotic plaques and brain tissue of patients bearing neurodegenerative diseases. These species can also react with amino acid residues leading to protein denaturation and malfunction. With that in mind, the second chapter of this study aims to investigate the reaction of ChAld and cytc. Using mimetic membrane models and mass spectrometry analyses, we showed that ChAld covalently modifies cytc through a mechanism consistent with the formation of Schiff base adducts. Such modification occurs mostly at lysine residues that are known to interact with the membrane. The modifications have an influence in the affinity of cytc to the membrane, where they increase its binding to the membrane, a process that could affect the electron transport and apoptosis signaling. In the last and third chapter of this study we wanted an analytical tool that allowed the investigation of protein adduction promoted by cholesterol and other sterols-derived oxidation products. In a study performed in collaboration with the Porter group from Vanderbilt University, we used analyses based on click chemistry to search for protein adduction. To address that, we first synthesized derivatives of cholesterol and 7-dehydrocholesterol (7-DHC, the immediate precursor of cholesterol) containing an alkynyl group in the side chain. The alkynyl group can be ligated to an azide group through a cycloaddition reaction, in a process known as click chemistry. After the synthesis and characterization of alkynyl derivatives, Neuro2a cells were treated with alkynyl-7-DHC and alkynyl-cholesterol to check their metabolism. HPLC-MS/MS analyses showed that both alkynyl derivatives are metabolized and converted into their respective esters. In addition, using a cell model for Smith-Lemli-Optiz Syndrome (SLOS), a disease characterized by the deficiency in the dehydrocholesterol reductase 7, we showed that the characteristic accumulation of 7-DHC in SLOS patients might be associated with protein adduction promoted by its oxidation products, which might contribute to the development of the disease

Carboidratos como matéria-prima para a preparação de substratos quirais: aplicações em catálise enantiosseletiva e processos diastereosseletivos / Carbohydrates as starting materials for the preparation of chiral substrates: applications in enantioselective and diastereoselective processes

O presente trabalho descreve o uso de carboidratos como materiais de partida para a preparação de catalisadores quirais e também de substratos quirais. Primeiramente estudos envolvendo a aplicação de amino álcoois derivados de carboidratos na arilação assimétrica de aldeídos, usando ácidos arilborônicos como fontes de grupos arila transferíveis, revelaram que um ligante preparado a partir da D-xilose mostrou-se bastante eficiente e conduziu aos produtos em excelentes rendimentos e altos excessos enantioméricos. Posteriormente a arilação de aldeídos derivados de carboidratos é descrita. Em alguns casos diastereosseletividades maiores que 20:1 foram observadas e a metodologia foi aplicada a síntese total da 7-epi-goniofufurona e análogos

The work described herein is centered on the use of carbohydrates as starting materials for the synthesis of chiral ligands and chiral sugar-derivatives. Initially, chiral amino alcohols were studied as ligands for the asymmetric arylation of aldehydes using aryl boronic acids as the source of transferable aryl groups. We found that a chiral ligand derived from D-xylose was very efficient and the desired products were obtained in excellent yields and enantiomeric excesses. In addition, the arylation of sugar-based aldehydes was also studied. In many cases, excellent diastereoselectivities of >20:1 were achieved and the methodology was employed in the total synthesis of 7-epi-goniofufurone and analogues

Water sorption of CH3- and CF3-Bis-GMA based resins with additives

OBJECTIVES: To evaluate the effect of additives on the water sorption characteristics of Bis-GMA based copolymers and composites containing TEGDMA, CH3Bis-GMA or CF3Bis-GMA. MATERIAL AND METHODS: Fifteen experimental copolymers and corresponding composites were prepared combining Bis-GMA and TEGDMA, CH3Bis-GMA or CF3Bis-GMA, with aldehyde or diketone (24 and 32 mol%) totaling 30 groups. For composites, barium aluminosilicate glass and pyrogenic silica was added to comonomer mixtures. Photopolymerization was effected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Specimen densities in dry and water saturated conditions were obtained by Archimedes' method. Water sorption and desorption were evaluated in a desorption-sorption-desorption cycle. Water uptake (%WU), water desorption (%WD), equilibrium solubility (ES; µg/mm³), swelling (f) and volume increase (%V) were calculated using appropriate equations. RESULTS: All resins with additives had increased %WU and ES. TEGDMA-containing systems presented higher %WU, %WD, ES, f and %V values, followed by resins based on CH3Bis-GMA and CF3Bis-GMA. CONCLUSIONS: Aldehyde and diketone led to increases in the water sorption characteristics of experimental resins.

Preservation of Haemal Nodes Fixed by Means of Two Different Aldehyde Fixatives: a Scanning Electron Microscopic Study / Preservación de Nodos Linfáticos Hemales Fijados por Dos Fijadores de Aldehído Diferentes: un Estudio de Microscopía Electrónica de Barrido

Glutaraldehyde is the fixative most commonly used in electron microscope studies of biological tissues, however it is often necessary to use samples which were not fixed in this fixative, even with the usual uncertainty of the results that may be obtained. The fixation is the more delicate step of the sample processing. Therefore in this work, the quality of preservation of haemal nodes fixed with two classic aldehyde fixatives: formaldehyde and glutaraldehyde we have compared under the scanning electron microscope. Our results showed that both fixatives were successful in preserving the morphology of haemal nodes components; however glutaraldehyde conferred satisfactory results mainly in the preservation of parenchymal cells, whereas formaldehyde was better for preservation of stromal fibres.

El glutaraldehido es el fijador que se utiliza con más frecuencia en estudios en los tejidos biológicos a través microscopía electrónica. Sin embargo, a menudo es necesario utilizar muestras que no han sido fijadas con este fijador, aún con la incertidumbre de los resultados que se puedan obtener. La fijación es el paso más importante en el procesamiento de los tejidos. Por lo anterior, hemos efectuado este estudio comparando la calidad de conservación de nodos linfáticos hemales fijados con formaldehido y glutaraldehido. Los resultados muestran que ambos fijadores conservaron adecuadamente la morfología de los componentes de los nodos linfáticos hemales, sin embargo, el glutaraldehido conservó en mejores condiciones, principalmente, las células del parénquima, pero el formaldehido conservó mejor las fibras del estroma en nodos linfáticos.

Influence of the pH of glutaraldehyde and the use of dextran aldehyde on the preparation of cross-linked enzyme aggregates (CLEAs) of lipase from Burkholderia cepacia

The preparation of cross-linked enzyme aggregates (CLEAs) of lipase has been a challenge due the low amount of lysine residues that lipases have on their surface. The results show that CLEAs prepared using dextran aldehyde (100-200KDa) have a higher hydrolysis activity and particle size (activities between 3186 +/- 21 U/g of CLEA and 4800 +/- 30 U/g of CLEA and particle sizes between 52.6 +/- 18.7 um and 126.2 +/- 53.5 um) than CLEAs prepared with glutaraldehyde (0.1 KDa) (activities between 894 +/- 16 U/g of CLEA and 2874 +/- 20 U/g of CLEA and particle sizes between 21.2 +/- 5.1 um and 83.4 +/- 24.9 um); Thermal stability assays of bioctalysts at 60 ºC at pH 7.0 using phosphate buffer 25 mM showed that CLEAs prepared with dextran aldehyde have lower residual activity after 50 hrs (maximum residual activity of 46.8 percent in the CLEA) than CLEAs prepared with glutaraldehyde (maximum residual activity of 70.2 percent in CLEA). When considering hydrolysis activity, thermal stability and residual activity of CLEAs as a criteria for selecting the best preparation conditions, it has been found that the best condition for CLEAs preparation are to use glutaraldehyde as cross-linking reagent at pH 9.5, at a concentration of 3.5 g/l, and an enzyme/albumin ratio of 15.

Anti-inflammatory and redox-protective activities of citronellal

The anti-inflammatory and redox protective effects of the citronellal (CT) were evaluated using in vivo and in vitro tests. Intraperitoneal (i.p.) administration of CT (50, 100, and 200 mg/kg) inhibited (p < 0.05) the carrageenan-induced leukocyte migration to the peritoneal cavity. Additionally, the carrageenan- and arachidonic acid-induced rat hind paw edema was significantly inhibited (p < 0.05) by i.p. administration of 100 and 200 mg/kg of the compound. When the redox activity was evaluated, CT (200 mg/kg) significantly reduced hepatic lipoperoxidation (p < 0.001), as well as oxidation of plasmatic (p < 0.05) and hepatic (p < 0.01) proteins. The results of the present study support the hypothesis that CT possesses anti-inflammatory and redox protective activities. It is suggested that its effects are associated with the inhibition of the enzymes in the arachidonic acid pathway, which prevent cell migration by inhibiting leukotriene production, edema formation and the increase of reactive oxygen species in tissues. Therefore, CT is of potential benefit to manage inflammatory disorders and correlated damages caused by oxidant agents.

Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection / Mycobacterium massiliense clone BRA100 associado a infecções pós-cirúrgicas: resistência a altas concentrações de glutaraldeído e produtos alternativos para desinfecção de alto nível

PURPOSE: To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). METHODS: Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5 percent to 8 percent), and commercial orthophthaldehyde (OPA) and peracetic acid (PA) - based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. RESULTS: All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8 percent GTA and were susceptible to OPA and PA. CONCLUSION: M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7 percent), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA - based solutions for HLD.

OBJETIVO: Avaliar a concentração mínima inibitória (CMI) de GTA frente a M. massiliense e a susceptibilidade a produtos alternativos para desinfecção de alto nível (DAN). MÉTODOS: Cepas de M. massiliense de origem clínica e de referência foram incluídas no estudo. As culturas ativadas foram submetidas a testes qualitativos com diluições de GTA (de 1,5 por cento a 8 por cento) e com soluções comerciais de ortoftaldeído (OPA) ou ácido peracético (PA), utilizando os tempos de exposição recomendados pela Agência Nacional de Vigilância Sanitária para DAN. RESULTADOS: Todas as cepas de referência e M. massiliense não-BRA100, obtida de escarro, foram susceptíveis às concentrações de GTA, e soluções de OPA e PA. As cepas de M. massiliense BRA100 apresentaram CMI de 8 por cento para GTA e foram susceptíveis a OPA e PA. CONCLUSÃO: M. massiliense BRA100 é resistente a altas concentrações de GTA (até 7 por cento), o que demonstra que esse composto não é eficaz, e deve ser substituído por OPA ou PA nos processos de DAN.

In vitro larvicidal activity of geraniol and citronellal against Contracaecum sp (Nematoda: Anisakidae)

Human infection with fish parasites can result from the ingestion of incompletely cooked or raw fish, giving origin to parasitic diseases such as anisakiasis, caused by parasites of the Anisakidae family. The present study assessed the in vitro larvicidal effect of two monoterpene compounds, geraniol and citronellal, against Contracaecum sp (Nematoda: Anisakidae). Four hundred live larvae of Contracaecum sp obtained from "traíra" fish (Hoplias malabaricus, Bloch, 1974) were analyzed on 40 Petri dishes (10 larvae each) with the compounds to be tested. The final concentrations tested for each compound were 250, 125, 62.5, and 31.2 µg/mL and the evaluation was carried out at five different times (2, 4, 8, 24, and 48 h). The larvicidal action of geraniol and citronellal was statistically superior (P < 0.005) to the control (1 percent ethanol) at concentrations of 250 and 31.2 µg/mL (geraniol) and 250, 125, and 62.5 μg/mL (citronellal). However, no larvicidal activity was observed at concentrations of 125 and 62.5 µg/mL for geraniol and 31.2 µg/mL for citronellal. When the larvicidal action of geraniol was compared to that of citronellal, the former was found to be statistically superior (P < 0.05) to the latter at concentrations of 250 and 31.2 μg/mL. On the other hand, citronellal was statistically superior (P < 0.005) to geraniol at concentrations of 125 and 62.5 μg/mL. The larval mortality rate in terms of time (hours) was higher for geraniol with the passing of time at the 250 μg/mL concentration. At this concentration (in 48 h) the best larvicidal effect was observed with 90 percent lethality. The larvae were considered to be dead using no motility and loss of structural integrity as parameters. The data indicate that natural terpene compounds should be more explored for antihelminthic activity and can be useful for other studies about anisakiasis treatment.

Novel antiviral activity of dialdehyde starch

A significant effort worldwide is being directed toward development of novel biocides against drug-resistant bacterial and viruses because of the significant potential human infection risks in the general population. We report here the discovery of a strong antiviral biocide, dialdheyde starch (DAS). Antiviral tests were carried out against three non-envelop viruses, including two bacterial viruses MS2 and PRD1, and one human virus Poliovirus. Dialdehyde starch aqueous suspensions were effective biocides against these three test viruses in a 1 hr exposure test. The antiviral activity was significantly enhanced in a four-hour exposure test, with maximum seven orders of magnitude reductions against MS2 and PRD1, and four-order reduction against Poliovirus. The antiviral activity of dialdehyde starch was found to be pH dependent, being more active in alkaline and acidic conditions than in neutral conditions.

Caracterização das emissões de aldeídos de veículos do ciclo diesel / Emission of aldehydes from light duty diesel vehicles

OBJETIVO: Caracterizar as emissões de acetaldeído e formaldeído, substâncias nocivas para a saúde das pessoas e cujas emissões dos veículos a diesel ainda não estão regulamentadas. MÉTODOS: Testes padronizados foram realizados em quatro veículos leves comerciais do ciclo diesel, testados num dinamômetro de chassis, usando o procedimento de teste FTP-75. Os poluentes foram analisados por cromatografia líquida de alta eficiência. RESULTADOS: Os resultados mostraram que a emissão de acetaldeído variou de 5,9 a 45,4 mg/km e a de formaldeído variou de 16,5 a 115,2 mg/km. A emissão média para a soma dos aldeídos foi de 58,7 mg/km, variando de 22,5 mg/km a 160 mg/km. A proporção entre os dois se manteve constante, próximo de 74 por cento de formaldeído e 26 por cento de acetaldeído. CONCLUSÕES: A emissão de aldeídos provenientes de veículos movidos a diesel foi significativa quando comparada com as emissões reais dos veículos de ignição por centelha ou com o limite previsto para os veículos do ciclo Otto na legislação brasileira. O estabelecimento de limites de emissão para essas substâncias para veículos a diesel mostra-se importante, considerando o crescimento da frota de veículos a diesel, a toxicidade desses compostos e sua participação como precursores nas reações de formação de gás ozônio na baixa troposfera.