Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
Add more filters










Publication year range
1.
Ann Soc Entomol de France (NS), v. 59, n.6, dez, 2023.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-5225

ABSTRACT

Three new species of the spider genus Speocera Berland, 1914 are described from caves of different lithologies, in the state of Minas Gerais, Brazil: Speocera canjica n. sp., S. pamonha n. sp. and S. vacaatolada n. sp., all based on males and females. Among the described species, S. vacaatolada n. sp., presents a palp morphology similar to that of Speocera pallida, where a reduction of bulb structures occurs. Résumé Trois nouvelles espèces du genre Speocera (Araneae : Ochyroceratidae) provenant de grottes de l'État de Minas Gerais, Brésil. Trois nouvelles espèces du genre d'araignées Speocera Berland, 1914, collectées dans des grottes de différentes lithologies de l'État de Minas Gerais, au Brésil, sont décrites : Speocera canjica n. sp., S. pamonha n. sp. et S. vacaatolada n. sp., toutes basées sur des mâles et des femelles. Parmi les espèces décrites, S. vacaatolada n. sp. est la première espèce avec une morphologie des palpes similaire à celle de Speocera pallida, où l’on constate une réduction des structures du bulbe.

2.
J Food Sci Technol ; 54(13): 4344-4352, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29184240

ABSTRACT

Most studies evaluating the use of essential oils (EO) as antibacterial agents focus mainly on minimal inhibitory concentrations (MIC) rather than minimal bactericidal concentrations (MBC). In this work, we compared MICs and MBCs of EO from condiment plants commonly used in Mediterranean Europe, namely Origanum vulgare, Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea and Rosmarinus officinalis, aiming to evaluate their application as disinfecting agents in minimally processed produce. Outbreaks-related pathogens such as Listeria monocytogenes, Pseudomonas aeruginosa and Yarrowia lipolytica were used. Results showed that all EO were able to reduce bacterial growth in all bacterial strains tested, particularly O. vulgare. However, fewer EO exhibited bactericidal activities, and were only effective against one or two bacterial strains, hence eliminating the possibility to use them as broad range disinfectants. Furthermore, the necessary concentrations were too high for food application. Hence, our work suggests the need to evaluate MBC rather than MIC and questions EO usefulness in controlling undesired microorganisms. Overall, and despite the large volume of data published on EO, results obtained were not very encouraging for a realistic application on produce and question the viability of EOs as disinfecting agents in food.

3.
Braz. j. biol ; 76(2): 428-434, Apr.-June 2016. tab, graf
Article in English | LILACS | ID: lil-781392

ABSTRACT

Abstract The antioxidant and anticandidal activities of leaves obtained from Camellia sinensis by non-fermentation (green and white teas), semi-fermentation (red tea) and fermentation method (black tea) were investigated. It was evaluated the total phenolic content by Folin-Ciocalteau assay; antioxidant capacities were evaluated in vitro using DPPH and ABTS radicals, hypochlorous acid and superoxide anion scavenger assays, induced hemolysis, lipid peroxidation by conjugated diene formation and myeloperoxidase activity. Anticandidal activity was performed on three strains of Candida spp. The results showed that non-fermented teas have a higher concentration of phenolic compounds, and then presented the best inhibitory activity of AAPH-induced hemolysis, the best inhibition of conjugated diene formation and more pronounced antioxidant activity in all tests. The highest anticandidal activity was obtained from fermented tea, followed by non-fermented tea. These results indicate that the antioxidant activity demonstrated has no direct relation with the anticandidal activity.


Resumo A atividade antioxidante e antifúngica das folhas obtidas da Camellia sinensis pelos métodos de não-fermentação (chás verde e branco), semi-fermentação (chá vermelho) e fermentação (chá preto) foram investigadas. Foi avaliado o conteúdo total de compostos fenólicos pelo método de Folin-Ciocalteau; a capacidade antioxidante foi avaliada in vitro usando os radicais artificiais DPPH e ABTS, o ácido hipocloroso, ensaios do ânion superóxido, hemólise induzida, peroxidação lipídica por formação de dienos conjugados e atividade da Mieloperoxidase. A atividade antifúngica foi obtida sobre três cepas de Candida spp. Os resultados obtidos mostram que os chás não fermentados apresentam a maior concentração de compostos fenólicos e também, apresentam a melhor atividade inibitória, sobre hemólise induzida por APPH, sobre a formação de dienos conjugados e a mais pronunciada atividade antioxidante sobre todos os testes. A maior atividade antifúngica foi obtida pelo chá fermentado, seguido pelo semi-fermentado e não-fermentados. Os resultados obtidos demonstram que a atividade antioxidante observada não apresenta relação com a atividade antifúngica.


Subject(s)
Plant Leaves/chemistry , Camellia sinensis/chemistry , Antifungal Agents/pharmacology , Antioxidants/pharmacology , Oxidation-Reduction , Phenols/analysis , Tea/chemistry , Plant Extracts , Lipid Peroxidation , Peroxidase/metabolism , Fermentation , Hemolysis , Antifungal Agents/analysis , Antioxidants/analysis
4.
Braz J Biol ; 76(2): 428-34, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26983085

ABSTRACT

The antioxidant and anticandidal activities of leaves obtained from Camellia sinensis by non-fermentation (green and white teas), semi-fermentation (red tea) and fermentation method (black tea) were investigated. It was evaluated the total phenolic content by Folin-Ciocalteau assay; antioxidant capacities were evaluated in vitro using DPPH and ABTS radicals, hypochlorous acid and superoxide anion scavenger assays, induced hemolysis, lipid peroxidation by conjugated diene formation and myeloperoxidase activity. Anticandidal activity was performed on three strains of Candida spp. The results showed that non-fermented teas have a higher concentration of phenolic compounds, and then presented the best inhibitory activity of AAPH-induced hemolysis, the best inhibition of conjugated diene formation and more pronounced antioxidant activity in all tests. The highest anticandidal activity was obtained from fermented tea, followed by non-fermented tea. These results indicate that the antioxidant activity demonstrated has no direct relation with the anticandidal activity.


Subject(s)
Antifungal Agents/pharmacology , Antioxidants/pharmacology , Camellia sinensis , Plant Leaves , Antifungal Agents/analysis , Antioxidants/analysis , Camellia sinensis/chemistry , Fermentation , Hemolysis , Lipid Peroxidation , Oxidation-Reduction , Peroxidase/metabolism , Phenols/analysis , Plant Extracts , Plant Leaves/chemistry , Tea/chemistry
5.
J Phys Chem A ; 112(15): 3432-43, 2008 Apr 17.
Article in English | MEDLINE | ID: mdl-18341311

ABSTRACT

This paper presents an overview of recent progress in spectroscopic studies of the energetic nitroimine 4,6-bis(nitroimino)-1,3,5-triazinan-2-one (DNAM), based on experimental and theoretical data. The following topics are considered: variable temperature FTIR spectroscopy (4000-400 cm(-1)) applied to the study of natural and isotopically substituted (deuterated) samples aiming to obtain a successful vibrational assignment of the spectra and to investigate H-bonding interactions; extensive theoretical work based on accurate quantum chemical calculations (ab initio MP2 and DFT/B3LYP; harmonic and anharmonic vibrational calculations) to model and help interpreting the experimental findings, as well as to provide fundamental data on this simple prototype nitroimine that can be used as a starting point to the study of more complex related compounds. This work allowed us to reveal detailed features of the IR spectrum of the title compound, presenting, for the first time, plausible assignments.

6.
J Phys Chem A ; 111(1): 150-8, 2007 Jan 11.
Article in English | MEDLINE | ID: mdl-17201397

ABSTRACT

This paper provides an overview of recent progress on structural data on the title compound. Theoretical work based on quantum mechanical calculations was performed to gain some understanding on the heterocyclic tautomerism potentially exhibited by the compound. The computational studies encompassed a wide range of tautomers/conformers, allowing the determination of the most probable molecular structure. In the gas phase, the nitroimine tautomers are computed to be substantially more stable than the nitramine tautomers. Among three plausible nitroimine forms, special attention was given to 4,6-bis(nitroimino)-1,3,5-triazinan-2-one, whose crystal structure was unequivocally solved by X-ray diffraction. The crystals are orthorhombic, space group Pnma with a = 6.187(2)A, b = 13.252(5)A, c = 8.802(4)A, and Z = 4. The structure was solved by direct methods and refined to a final R = 0.0326. The molecule has an approximate mirror plane relating the two symmetry related halves. The nitroimine groups are positioned in a syn-syn conformation. The least-squares (LS) plane of the heterocyclic ring and the nitroimine ([double bond]N-NO2) substituent LS plane make an angle of 10.05(11) degrees. The crystal structure is held together via hydrogen bonds that assemble the molecules in chains running along the b-axis. Every H-atom is involved in bifurcated hydrogen bonds.

7.
Neuroscience ; 91(4): 1291-7, 1999.
Article in English | MEDLINE | ID: mdl-10391436

ABSTRACT

Transient global cerebral ischemia induced in rats by four-vessel occlusion for 20 min produced an increase in the immunocontent of glial fibrillary acidic protein and a protein phosphorylation response that was different in the CA1 and dentate gyrus areas of the hippocampus. We studied different times of reperfusion (one, four, seven, 14 and 30 days) and observed that the immunocontent and in vitro rate of phosphorylation of glial fibrillary acidic protein in the CA1 region was significantly increased at all intervals after the ischemic insult, indicating that the astrocytic response was maintained for at least 30 days. After reperfusion for 14 days a significant increase in the ratio "in vitro phosphorylation rate/immunocontent" in the CA1 region was observed when compared to control values, to other intervals and to the dentate gyrus, suggesting a hyperphosphorylation of this intermediate filament protein at this interval. In the dentate gyrus, an area less vulnerable to the insult, labelling and immunocontent of glial fibrillary acidic protein were equally increased from four days of reperfusion and the increase remained significant until 30 days, confirming that neuronal death is not the only determining factor for gliosis to occur. In control sham-operated animals, neither the CA1 region nor the dentate gyrus showed significant increases in labelling or immunocontent. Changes in the phosphorylation of glial fibrillary acidic protein may be essential for the plastic response of astrocytes to neuronal damage, as neurons and astrocytes can act as functional units involved in homeostasis, plasticity and neurotransmission.


Subject(s)
Glial Fibrillary Acidic Protein/metabolism , Hippocampus/metabolism , Ischemic Attack, Transient/metabolism , Animals , Immunologic Techniques , Phosphoproteins/metabolism , Phosphorylation , Rats , Rats, Wistar
8.
Article in English | AIM (Africa) | ID: biblio-1271954

ABSTRACT

The authors examined a series of 400 children from different dental clinics of the island; aged 9 to 14 years; who were referred for malocclusion to the Orthodontic service. They found that a large proportion of children (25 per cent) had to be referred for orthodontic treatment. The most frequently retained teeth were the second superior and inferior premolars. They recommend (1) to increase the necessary conservation of the primary molars in the dental arch; (2) to maintain the space in the case of premature loss due to whatever reason; (3) to re-establish the contact points to prevent loss of the dental arch length; and (4) to promote proper institutional procedures for dental surveillance and prevention in children


Subject(s)
Malocclusion
SELECTION OF CITATIONS
SEARCH DETAIL
...