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411.
412.
Rossana de Aguiar Cordeiro Ana Raquel Colares de Andrade Fernando Victor Monteiro Portela Lívia Maria Galdino Pereira Santiago Gonçalves Bezerra Moura Mônica Dantas Sampaio 《Biofouling》2020,36(5):610-620
AbstractThis study proposes a microcosm biofilm (MiB) model for the study of vulvovaginal candidiasis (VVC). Different conditions that mimic the vaginal environment were tested for MiB formation. The best growth conditions were obtained with samples incubated in vaginal fluid simulator medium pH 4.5 at 35?°C under a microaerophilic atmosphere. MiBs were evaluated for growth kinetics, fluconazole susceptibility and morphology. Samples containing high numbers of bacteria were analyzed for metagenomics. At 48?h, MiBs presented a higher cell density (CFU ml?1), a higher biomass and tolerance to fluconazole than their corresponding monospecies biofilms. Morphological analysis of MiBs revealed blastoconidia preferentially adhered to epithelial cells. Abundant Lactobacillus spp. were detected in two clinical samples; their MiBs showed a lower biomass and a higher fluconazole susceptibility. The proposed model proved to be a useful tool for the study of the complex microbial relationship in the vaginal environment, and may help to find new strategies for VVC control. 相似文献
413.
A Favre R Bezerra E Hajnsdorf Y Lemaigre Dubreuil A Expert-Bezan?on 《European journal of biochemistry》1986,160(3):441-449
In vivo incorporation of the uridine-photoactivable analogue, 4-thiouridine, into the ribosomal RNA of an Escherichia coli pyrD strain has been demonstrated. It is highly dependent on the exogenous uridine and 4-thiouridine concentrations as well as on temperature. We have defined conditions allowing the substitution of 13 +/- 2% of the uridine residues in bulk RNA by 4-thiouridine. On a high-Mg2+ sucrose gradient, 33 +/- 3% of ribonucleic particles sediment as 70S ribosomes, the remaining being in the form of non-associated 50S and 30S particles containing immature rRNA. The thiolated 70S ribosomes tolerate a 4-5% substitution level (40 thiouridine molecules/particle). Surprisingly, 3-4% of ribosomal proteins, about two protein molecules/particle, were spontaneously covalently bound to 4-thiouridine-substituted rRNA. Specific 366-nm photoactivation increased this proportion to 10-12%, i.e. up to six or seven ribosomal protein molecules/particle. The photochemical cross-linking proceeds with apparent first-order kinetics with a quantum yield close to 5 X 10(-3). Although extensive photodynamic breakage of rRNA occurs under aerobic conditions, both the kinetics and yield of ribosomal protein cross-linking were independent of oxygenation conditions. The thiolated (4.5%) 70S ribosomes allowed the poly(U)-directed poly(Phe)synthesis at 48% the control rate. Photoactivation decreased this activity to 28% and 10% when performed under nitrogen and in aerated conditions, respectively. 相似文献
414.
Riccardo Castiglia Andrés García Alexandra M. R. Bezerra Oscar Flores-Villela Ekaterina Gornung 《Rendiconti Lincei》2009,20(1):77-82
We analyzed chromosomes of male and female individuals of Phyllodactylus lanei Smith, 1935 (Squamata, Gekkonidae) from Chamela-Cuixmala Biosphere Reserve, Jalisco state, Mexico. The karyotype constructed
for these specimens is composed of 19 pairs of telocentric chromosomes (2n = 38, FN = 38). This karyotype, due to Robertsonian
fusions/fissions, differs from the one previously reported in samples from the State of Guerrero, which probably belonged
to a different subspecies (2n = 33−34, FN = 40−41). Moreover, a presumed ZW sex chromosome system was not confirmed in the
presently studied individuals.
相似文献
415.
416.
Predation on arboreal mammals is rarely observed in the wild. Here we describe the first confirmed observations of predation
on a juvenile wild common marmoset (Callithrix jacchus) and on a neonate wild pale-throated three-toed sloth (Bradypus tridactylus) by the mustelid carnivore Eira barbara, the tayra. We discuss predation on both of the prey species and review the nature of predation by the tayra. 相似文献
417.
418.
Maria Conceição M. Torres João Carlos Assunção Gilvandete Maria P. Santiago Manoel Andrade‐Neto Edilberto R. Silveira Leticia V. Costa‐Lotufo Daniel P. Bezerra José Delano B. Marinho Filho Francisco Arnaldo Viana Otília Deusdênia L. Pessoa 《化学与生物多样性》2008,5(12):2724-2728
The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC‐FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9–17.0%), p‐cymene (22.3–21.6%), and camphor (13.0–3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae. 相似文献