5 research outputs found
Aminoácidos não protéicos de Ateleia glazioviana Baillon
Ateleia glazioviana Baillon, Leguminosae-Papilionoideae, árvore de ocorrência na região de Palmeira das Missões (RS), possui atividade tóxica para o gado, ictiotóxica e repelente de insetos, referida por populares do interior do estado. Do extrato de sementes e pericarpo alado, foram isolados três aminoácidos não protéicos, dois dos quais identificados como o ácido 1-aminociclobutano-1,3-dicarboxÃlico e δ-acetilornitina.Ateleia glazioviana Baillon, Leguminosae-Papilionoideae, is a tree widespread in the state of Rio Grande do Sul. It is reputed to be toxic to cattle, fish and repellent to insects. In this work, two of the main non proteinogenic amino acids were identified through spectroscopic methods as 1-aminociclobutane-1, 3-dicarboxilic and δ-acetylornithine
Selection of moxifloxacin-resistant Staphylococcus aureus compared with five other fluoroquinolones
Fluoroquinolone-resistant mutants were selected from Staphylococcus aureus NCTC 8532 (F77), and two GrlA mutants of F77 (F193 and F194) with moxifloxacin, sparfloxacin, ofloxacin, grepafloxacin, levofloxacin and trovafloxacin. For mutants selected from F77, moxifloxacin,
grepafloxacin and sparfloxacin selected preferentially for mutations in gyrA (Glu-88→Lys). Ofloxacin and trovafloxacin selected most commonly for mutations in grlA, conferring substitutions for Ser-80. Three mutants of F77 were shown to have substitutions in both GrlA (Phe-80) and GyrA (Lys-88). Of the mutants selected from F193 (GrlA Phe-80), restriction fragment length polymorphism analysis of gyrA showed that 76/94 had a mutation at codon 84; those analysed in detail all had the substitution Ser→Leu. Two mutants selected with grepafloxacin contained the substitution Lys-88. One mutant selected with trovafloxacin contained a novel mutation in gyrA
substituting Gly-82→Cys. Of the mutants selected from F194 (GrlA Tyr-80), 6/8 had a mutation in gyrA codon 84; of which three contained Leu. The MICs of most agents for mutants selected from F193 and F194 were similar, irrespective of the mutation selected. No mutants had any changes in grlB, and only one had a mutation in gyrB giving rise to the novel substitution Asp-437→His.
The mutations arising in first-step mutants were influenced by the fluoroquinolone used for selection. The phenotypes and genotypes of second-step mutants, derived from mutants with existing mutations in grlA, were similar, regardless of the selecting antibiotic
Sparfloxacin and the fluoroquinolones : a review of classification, antibacterial activity, mechanism of action, pharmacokinetic properties, tolerability and pharmaceutical perspectives
Foi realizada uma revisão na literatura sobre as quinolonas, classe antibacteriana que possui amplo espectro de ação, enfocando, principalmente, o esparfloxacino, fluorquinolona de terceira geração que possui potente atividade contra bactérias Gram-positivas, como Streptococcus pneumoniae e Staphylococcus auieus inclusive cepas metilina resistentes (MRSA), bactérias Gram-negativas, anaeróbios, Legionella spp, Mycoplasma spp, Chlamydia spp e MycobacterÃum spp.A revision was accomplished in the literature on the quinolones, antibactenal class that presents wide action spectrum, focusing, mainly, the sparfloxacin, third generation fluorquinolone which has potente activity against Gram positive organisms, including Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA), Gram negative organisms, Legionella spp, Mycoplasma spp, Chlamydia spp and Mycobacterium spp, including multidrug resistant organisms
Cytotoxic activity of sparfloxacin and its degradation products in mononuclear human blood cells
O esparfloxacino (SPAX) é uma fluoroquinolona antibacteriana de amplo espectro e apresenta potente atividade contra bactérias gram-positivas, incluindo Streptococcus pneumoniae e Staphylococcus aureus inclusive cepas meticilina resistentes (MRSA), bactérias gram-negativas, não fermentadoras de glicose, anaeróbios, Legionella spp; Mycoplasma spp; Chlamydia spp e Mycobacterium spp. Uma importante caracterÃstica desta classe de antimicrobianos é a fototoxicidade. Esparfloxacino tem sido estudado quanto à s suas atividades terapêuticas, entretanto poucos métodos de análise são descritos na literatura. Este trabalho objetivou a determinação dos efeitos citotóxicos de esparfloxacino substância de referência (SPAX-SR), esparfloxacino comprimidos (SPAX-COMP), esparÃloxacino comprimidos su metidos à luz por 36 horas (SPAX-COMP.36), e dois produtos (7 e 9) isolados após a fotodegradação de esparfloxacino sob luz UV-C nas concentrações de 31,25; 62,5; 125 e 250 μ.g/mL, sobre o cultivo in vitro de células mononucleares humanas. Os resultados, analisados estatisticamente pelo Teste de Tukey, demonstraram que as soluções de esparfloxacino (SPAX-SR), SPAX-COMP e SPAX-COMP.36 em concentração de 250 μg/mL reduziram significativamente o número de células viáveis nestas condições. Este resultado não foi observado para as soluções das substâncias 7 e 9, o que sugere que estes produtos sejam menos citotóxicos do que o SPAX-SR, nas condições empregadas.Sparfloxacin, a difluorquinolone derivative, is a potent antibacterial agent active against a wide range of gram-positive and gram-negative organisms including Streptococcus pneumoniae, Staphylococcus aureus, methicillin resistant Saureus, Legionella spp, Mycoplasma spp; Chlamydia spp and Mycobacteria. A drawback of fluorquinolones is their photoreactivity. Sparfloxacin has been studied in terms of therapeutic activities. However, few reports about analytical methods of sparfloxacin are available in the literature. The aim of this study was to determine cytotoxic effects, using sparfloxacin reference substance (SPAX-SR), sparfloxacin tablets (SPAX-COMP) and sparfloxacin tablets submitted UV light during 36 hours (SPAX-COMP.36) solution, and two isolated products (7 and 9) of SPAX-SR submitted UV-C light, in concentrations of 31.25, 62.5, 125 and 250 μg/mL by in vitro mononuclear humane culture cells. The results, statistically analyzed by Teste de Tukey, showed SPAX, SPAX-COMP and SPAX-COMP.36 solutions could reduce the cells number in these conditions. These results could not be observed for products 7 or 9. These results can suggest that isolated product can be less cytotoxic than SPAX-SR, is method can also be used to identified products degradation of sparfloxacin in stability study. However, the low activity achieved with sparfloxacin submitted to UV-light is a source of concern and requires further investigation about its photodegradation mechanism