1,313 research outputs found

    The effect of thyme and tea tree oils on morphology and metabolism of Candida albicans

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    Members of Candida species cause significant problems in medicine and in many industrial branches also. In order to prevent from Candida sp. development, essential oils are more and more frequently applied as natural, non-toxic, non-pollutive and biodegradable agents with a broad spectrum of antimicrobial activity. The aim of the research was to determine changes in morphology and metabolic properties of Candida albicans in the presence of thyme and tea tree oils. Changes of enzymatic activity of isolates were observed in the presence of both tested essential oils, and they were primarily associated with loss or decrease of activity of all enzymes detected for control. Furthermore, only for 3 out of 11 isolates additional activity of N-acetyl-β-glucosaminidase, α-mannosidase, α-fucosidase and trypsin was detected. Vivid changes in biochemical profiles were found after treatment with tea tree oil and they were related to loss of ability to assimilate d-xylose, d-sorbitol and d-trehalose. The main differences in morphology of isolates compared to the control strain concerned formation of pseudohyphae structures. Both examined essential oils caused changes in cell and colony morphology, as well as in the metabolism of Candida albicans. However, the extent of differences depends on the type and concentration of an essential oil. The most important finding is the broad spectrum of changes in yeast enzymatic profiles induced by thyme and tea tree oils. It can be supposed that these changes, together with loss of ability to assimilate saccharides could significantly impact Candida albicans pathogenicity

    Rompiendo barreras: Susan Glaspell y el teatro norteamericano / Breaking out: Susan Glaspell and the American Theatre

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    RESUMEN: Las obras de la dramaturga norteamericana Susan Glaspell (1876-1948) fueron representadas principalmente por los Provincetown Players, grupo teatral del que fue co-fundadora. Sin embargo, a partir de 1922, apenas se representaron, con la excepción de Alison’s House, escrita en 1930 y que le ganó el prestigioso Premio Pulitzer de teatro. Después de su muerte, tanto las obras teatrales como sus novelas y relatos fueron aparcados en el olvido, salvo la obra corta Trifles, que Glaspell re-escribió como el relato «A Jury of Her Peers». Ambas piezas fueron reconocidas como obras maestras de la literatura feminista norteamericana en los años setenta/ochenta. En este artículo se repasa las obras principales de Glaspell, haciendo ver su enorme habilidad para integrar las corrientes teatrales europeas en piezas intrínsecamente americanas así como su maestría en la innovación teatral. Glaspell rompió muchas barreras artísticas y sociales con sus obras, entrando así de lleno en la corriente modernista de su época, lo cual se puede apreciar en las reposiciones recientes de sus obras en EEUU y en Inglaterra. ABSTRACT: The plays of the American dramatist Susan Glaspell (1876-1948) were staged mainly by the Provincetown Players, a Little Theatre of which she was one of the co-founders. However, as from 1922 her plays were rarely, if ever, produced, with the exception of Alison’s House, written in 1930, which gained her the prestigious Pulitzer Prize for Drama. After her death, except for the short play Trifles, which she rewrote as the short story «A Jury of Her Peers», her oeuvre was forgotten. Both pieces were recognized as masterpieces of feminist literature in the seventies/eighties. This article looks at Glaspell’s main plays in order to show her ability to integrate the European theatrical trends of the time in truly American plays, and at her skills as a theatrical innovator. Glaspell broke the artistic and social boundaries of her time in her plays, thus entering the mainstream of the modernist tradition; this can be appreciated in the recent revivals of her work in the USA and in England

    Pre-columbian archeological textiles: A source of pseudomonas aeruginosa with virulence attributes

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    Pseudomonas aeruginosa is an opportunistic pathogen associated with a broad spectrum of infections in humans. However, the pathogenicity of environmental P. aeruginosa strains, especially isolates from museums and conservation laboratories, is not widely recognized. In this study, the virulence attributes of P. aeruginosa isolated from pre-Columbian textiles were compared to those of a clinical strain. Both genetically identified environmental strains (KP842564 and KP842565) exhibited a high ability to form biofilms on abiotic surfaces and high hemolytic activity. In addition, strain KP842564 was a moderate pyocyanin producer and showed proteolytic properties toward bovine serum albumin, fibrinogen, mucin, and casein. In contrast to the clinical isolate, the environmental strainswere susceptible to all the tested antimicrobial agents. The strains also showed high bioadhesion and colonization capacity on archeological textile samples, in which wool fibers were the only source of nutrients, as confirmed by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) analysis. This study highlights the need to identify microorganisms which inhabit historic objects, in order to avoid exposure to occupational hazards. Although the strain KP842565 exhibited only some of the examined virulence-related features, given that the production of pyocyanin and hemolysins as well as the formation of biofilm are important virulence factors of P. aeruginosa, the results indicate that these strains may present a potential health risk for humans.Fil: Rajkowska, Katarzyna. Lodz University of Technology; PoloniaFil: Otlewska, Anna. Lodz University of Technology; PoloniaFil: Guiamet, Patricia Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias; ArgentinaFil: Wrzosek, Henryk. Lodz University of Technology; PoloniaFil: Machnowski, Waldemar. Lodz University of Technology; Poloni

    The Trends and Prospects of Winemaking in Poland

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    Viticulture and winery origins in Poland date to the tenth century, but their tradition has been reborn in the last ten years, resulting in a development of small vineyards producing excellent wines not only for the local market. Due to the cold climate, usually short summers with moderate and low temperatures, the grapes are characterized by lower sugar content and higher acidity compared to those grown in the south of Europe. According to the European Union regulations, Poland was classified as the coldest wine-growing region (A) and officially acknowledged as a wine-producing country. The grapevine cultivars adopted to the harsh climatic conditions give the Polish grape wines some unique sensory features. The most popular varieties of grapes for the production of red wine are Regent, Rondo, Pinot Noir, Maréchal Foch, Cabernet Cortis, Tryumf Alzacji, Cascade and Dornfelder. For white wine production, Solaris, Riesling, Seyval Blanc, Pinot Gris, Johanniter, Jutrzenka, Hibernal, Aurora, Bianka, Traminer, Jutrzenka and Siberia are mostly used in Poland. This chapter presents Polish grape winery with its specificity and prospects for the future. The traditional products of Polish fermentation industry, fruit wines and meads, are also mentioned

    Probiotička aktivnost kvasca Saccharomyces cerevisiae var. boulardii u sprečavanju patogenih bakterija

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    Infectious diarrhoea is associated with a modification of the intestinal microflora and colonization of pathogenic bacteria. Tests were performed for seven probiotic yeast strains of Saccharomyces cerevisiae var. boulardii, designated for the prevention and treatment of diarrhoea. To check their possible effectiveness against diarrhoea of different etiologies, the activity against a variety of human pathogenic or opportunistic bacteria was investigated in vitro. In mixed cultures with S. cerevisiae var. boulardii, a statistically significant reduction was observed in the number of cells of Listeria monocytogenes, Pseudomonas aeruginosa and Staphylococcus aureus, by even 55.9 % in the case of L. monocytogenes compared with bacterial monocultures. The influence of yeasts was mostly associated with the shortening of the bacterial lag phase duration, more rapid achievement of the maximum growth rates, and a decrease by 4.4–57.1 % (L. monocytogenes, P. aeruginosa), or an increase by 1.4–70.6 % (Escherichia coli, Enterococcus faecalis, Salmonella Typhimurium) in the exponential growth rates. Another issue included in the research was the ability of S. cerevisiae var. boulardii to bind pathogenic bacteria to its cell surface. Yeasts have shown binding capacity of E. coli, S. Typhimurium and additionally of S. aureus, Campylobacter jejuni and E. faecalis. However, no adhesion of L. monocytogenes and P. aeruginosa to the yeast cell wall was noted. The probiotic activity of S. cerevisiae var. boulardii against human pathogens is related to a decrease in the number of viable and active cells of bacteria and the binding capacity of yeasts. These processes may limit bacterial invasiveness and prevent bacterial adherence and translocation in the human intestines.Promjene u crijevnoj mikroflori uzrokuju naseljavanje patogenih bakterija i infektivni proljev. Ispitano je sedam probiotičkih sojeva kvasca Saccharomyces cerevisiae var. boulardii radi prevencije i liječenja proljeva. Istražena je in vitro aktivnost tih sojeva u sprečavanju različitih patogenih i oportunističkih bakterija da bi se utvrdila njihova učinkovitost pri liječenju različitih uzroka proljeva. U miješanim kulturama kvasca S. cerevisiae var. boulardii, za razliku od monokultura, opaženo je statistički značajno smanjenje broja bakterija Listeria monocytogenes (i to čak za 55,9 %), Pseudomonas aeruginosa i Staphylococcus aureus. Prisutnost kvasaca prije svega skraćuje fazu mirovanja bakterija (lag faza), zatim ubrzava postizanje maksimuma rasta, te smanjuje stopu eksponencijalnog rasta za 4,4-57,1 % (L. monocytogenes, P. aeruginosa) ili ju povećava za 1,4-70,6 % (Escherichia coli, Enterococcus faecalis, Salmonella Typhimurium). Osim toga, ispitana je sposobnost vezivanja patogenih bakterija na površinu stanica kvasca S. cerevisiae var. boulardii. Kvasci su uspješno vezali bakterije E. coli, S. Typhimurium, S. aureus, Campylobacter jejuni i E. faecalis, ali ne i L. monocytogenes i P. aeruginosa. Probiotičkom aktivnošću kvasca S. cerevisiae var. boulardii smanjuje se broj živih i aktivnih stanica patogenih bakterija koje su se vezale na stanice kvasca. Ti procesi ograničavaju invazivnost bakterija i sprečavaju njihovo vezanje za stijenke crijeva

    The representation of abstract task rules in the human prefrontal cortex

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    We have previously reported sustained activation in the ventral prefrontal cortex while participants prepared to perform 1 of 2 tasks as instructed. But there are studies that have reported activation reflecting task rules elsewhere in prefrontal cortex, and this is true in particular when it was left to the participants to decide which rule to obey. The aim of the present experiment was to use functional magnetic resonance imaging (fMRI) to find whether there was activation in common, irrespective of the way that the task rules were established. On each trial, we presented a word after a variable delay, and participants had to decide either whether the word was abstract or concrete or whether it had 2 syllables. The participants either decided before the delay which task they would perform or were instructed by written cues. Comparing the self-generated with the instructed trials, there was early task set activation during the delay in the middle frontal gyrus. On the other hand, a conjunction analysis revealed sustained activation in the ventral prefrontal and polar cortex for both conditions. We argue that the ventral prefrontal cortex is specialized for handling conditional rules regardless of how the task rules were established

    The New Inhibitor of Monoamine Oxidase, M30, has a Neuroprotective Effect Against Dexamethasone-Induced Brain Cell Apoptosis

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    Stress detrimentally affects the brain and body and can lead to or be accompanied by depression. Although stress and depression may contribute to each other, the exact molecular mechanism underlying the effects is unclear. However, there is a correlation between stress and an increase in glucocorticoid secretion which causes a subsequent increase in monoamine oxidase (MAO) activity during stress. Consequently, MAO inhibitors have been used as traditional antidepressant drugs. Cellular treatment with the synthetic glucocorticoid, dexamethasone (a cellular stressor), has been reported to markedly increase both MAO A and MAO B catalytic activities, as well as apoptosis. This study compares the neuroprotective abilities of M30 (a new generation inhibitor of both MAO A and MAO B) with rasagiline (Azilect®, another new MAO B inhibitor) and selegiline (Deprenyl®, a traditional MAO B inhibitor) in the prevention of dexamethasone-induced brain cell death and MAO activity in human neuroblastoma cells, SH-SY5Y. M30 demonstrated the highest inhibitory effect on MAO A; however, M30 showed the lowest inhibitory effect on MAO B enzymatic activity in comparison to rasagiline and selegiline. Although, M30 exhibited the greatest neuroprotective effect by decreasing cell death rates and apoptotic DNA damage compared to rasagiline and selegiline, these neuroprotective effects of M30 were, overall, similar to rasagiline. Summarily, M30 has a generally greater impact on neuroprotection than the MAO B inhibitors, selegiline and rasagiline. Our results suggest that M30 may have great potential in alleviating disorders involving increases in both MAO A and MAO B, such as stress-induced disorders
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