One-scale model for domain wall network evolution Avelino, P. P.; Martins, C. J. A. P.; Oliveira, J. C. R. E.
Physical review. D, Particles, fields, gravitation, and cosmology,
10/2005, Letnik:
72, Številka:
8
Journal Article
Paraquat (PQ) is a free-radical producing herbicide that affects cell membranes and can upset the environmental balance of microorganisms present in soil, such as Cryptococcus spp. This study aimed ...to evaluate the in vitro activity of PQ against Cryptococcus spp. in planktonic and biofilm forms, as well as the protective effect of antioxidant agents against the antifungal effect of PQ and the kinetics of melanin production in response to PQ. Susceptibility to PQ was evaluated by the microdilution. Cryptococcus sp. strains exposed to PQ were grown in media with ascorbic acid (AA) and glutathione (GSH). Melanin production was assessed in the presence of L-dopa + PQ. The minimum inhibitory concentration (MIC) of PQ against Cryptococcus spp. ranged from 8 -256 μg/mL. Furthermore, PQ reduced biofilm formation. AA and GSH restored the fungal growth of Cryptococcus spp. exposed to PQ. In addition, L-dopa + PQ delayed melanin production by 24 and 48 hours for C. deuterogattii and C. neoformans sensu lato, respectively, suggesting that PQ induces a fitness trade off in melanin production. Taken together, our data suggest that antifungal effect of PQ against Cryptococcus spp. exerts a possibly selective pressures interfering with biofilm formation and melanin production by these yeasts.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT Technologies once applied exclusively in conventional systems have maximized gains in hydroponic systems; however, they still need information for proper use. Thus, the study aimed to ...evaluate the effect of foliar application of thiamine and niacin on growth and gas exchange activities in two lettuce cultivars in an ebb and flow hydroponic system. The completely randomized design (CRD) was used with four treatments and eight replications. The treatments were as follows: T1 - control, T2 - thiamine at a concentration of 200 mg L-1, T3 - niacin at 200 mg L-1, and T4 - thiamine and niacin combined at 100 mg L-1 of each vitamin. Each experimental plot consisted of a lettuce plant. The combined application of thiamine and niacin stood out, increasing the activity of gas exchange of lettuce plants and increasing by about 30% the fresh mass, concerning the control, for both cultivars, followed by the isolated application of niacin. For thiamine, the application alone did not result in significant changes. The vitamins affect the morphophysiology of lettuce, where the use of niacin has the potential for use in hydroponic production systems. Its combined use with thiamine increases this potential, with a synergistic effect between the compounds being verified.
RESUMO Tecnologias outrora aplicadas exclusivamente em sistemas convencionais, têm maximizado os ganhos em sistemas hidropônicos, porém, necessitando ainda de informações para uma adequada utilização. Assim, o estudo teve como objetivo avaliar o efeito da aplicação foliar de tiamina e niacina sobre o crescimento e atividades de troca gasosa em duas cultivares de alface em sistema hidropônico de fluxo e refluxo. O delineamento experimental utilizado foi o inteiramente casualizado (DIC), com quatro tratamentos e oito repetições. Os tratamentos foram: T1 - controle; T2 - tiamina em concentração de 200 mg L-1; T3 - niacina em concentração de 200 mg L-1; T4 - tiamina e niacina combinadas, em concentração de 100 mg L-1 de cada vitamina. Cada parcela experimental foi constituída por um vaso, contendo uma muda de alface. A aplicação conjunta de tiamina e niacina elevou as trocas gasosas das plantas de alface, aumentando em cerca de 30% a massa fresca, em relação ao controle, para ambas as cultivares, seguida pela aplicação isolada de niacina. Para a tiamina, a aplicação de forma isolada não resultou em alterações significativas. As vitaminas afetam a morfofisiologia da alface, onde o uso da niacina tem potencial para uso em sistemas de produção hidropônicos, sendo esse potencial aumentado pelo seu uso conjunto com a tiamina, verificando-se um efeito sinérgico entre os compostos.
We investigated the effects of physical detraining on lipogenesis/lipolysis and cellularity (apoptosis/adipogenesis) in rat subcutaneous (inguinal; SC) and visceral (retroperitoneal; RP) white ...adipose depots.
Three groups of male Wistar rats (6-wk old) were studied: (1) (T) trained for 12 weeks; (2) (D) trained for 8 weeks and detrained for 4 weeks; and (3) (S) age-matched sedentary. Training consisted of treadmill running sessions (1 h/day, 5 days/week, 50–60% maximal race capacity).
Physical detraining increased glucose oxidation, lipogenesis, and adipocyte size in the SC and RP depots. The number of apoptotic SC adipocytes was reduced by 53% in the T (p < 0.0001) and by 43% in the D (p < 0.001) as compared with S. RP adipocyte apoptosis in the T and D was 9.48% and 10.9% greater compared to the S, respectively (p < 0.05). In the SC stromal vascular fraction (SVF) of D rats, adiponectin, sterol regulatory element binding protein (SREBP)-1c, Peroxisome proliferator-activated receptor gamma (PPARγ), and Perilipin A mRNA expressions were more pronounced than S group, suggesting a more intense adipogenesis. This putative adipogenic effect was not observed in the RP depot. The physical detraining promoted rapid increase in the SC and RP depots however not through the same mechanisms.
Physical detraining induced fat cell hypertrophy (increase of lipogenesis) in both SC and RP whereas hyperplasia (increase of adipogenesis and reduction of apoptosis) was found in SC only. These results indicate the mechanism associated with obesogenic effects of detraining varies with the fat depot.
Hair is one widely used alternative matrix for endocrine studies. Not only can it maintain hormone content during storage for long periods of time, but its collection also induces little to no ...stress. Noninvasive techniques have broadened the opportunities for endocrine research, particularly regarding wild animals. Despite its advantages, many sources of variation may affect the steroid concentration found in hair, such as body location harvested, fur color, reproductive status, and sex. Thus, domestic species, such as the dog, are an excellent and approachable model for understanding this variability. For such, we addressed diverse sources of variation in testosterone concentrations from 24 domestic dogs (Canis lupus familiaris) of the Poodle breed of various colors and neuter status, and from both sexes. The variation comprised the comparison between 2 different matrices (blood vs hair); 2 different extraction storage methods (refrigerator vs freezer); 3 body regions (head, torso, and limbs); 3 coat colors (black, brown, and white); different neuter status (intact vs castrated males) and, finally, sex. Our results showed no correlation between blood and hair testosterone concentrations. Additionally, we did not find differences related to the storage method, body region, or coat color. There were differences in concentration between males and females, but not between females and castrated males. We discuss hair testosterone levels exhibited reasonable stability, and we present practical applications for both domestic and wildlife animals.
•We established hair as a promising noninvasive matrix for monitoring testosterone in dogs and, hopefully, wild canids.•Testosterone concentrations in hair are relatively stable, even when stored on refrigerator.•There were no differences in hormone concentrations among distinct body regions or coat colors.•As expected, we found differences according to sex and neuter status (however, there was no difference between spayed males and entire females).
AIM: To establish whether virulence factor genes vacA and cagA are present in Helicobacter pylori (H. pylori) retrieved from gastric mucosa and dental plaque in pa-tients with dyspepsia. METHODS: ...Cumulative dental plaque specimens and gastric biopsies were submitted to histological exami-nation, rapid urease test and polymerase chain reac-tion (PCR) assays to detect the presence of cagA and vacA polymorphisms.RESULTS: Detection of H. pylori from dental plaque and gastric biopsy samples was greater by PCR co...
We present chitosan (CHT)/heparin (HP) polyelectrolyte complexes (PECs) that quickly adsorb citrate-capped silver nanoparticles (AgNPs). CHT/HP blends in ionic liquid (HMImHSO4) form durable PECs ...after precipitation in water. CHT/HP PECs have positive Zeta potentials (higher than +20 mV). They adsorb citrate-capped AgNPs (Zeta potential of - 12.25 mV) synthesized from Turkevich's method. PEC/AgNPs composites are characterized by spectroscopic, thermal, and microscopy analyses. AgNPs on the PEC surfaces are confirmed by transmission electron microscopy. PECs adsorb AgNPs from aqueous suspensions, achieving ≈ 95% of removal (17.18 μg of AgNPs per milligram of PEC) after only 10 min. The pseudo-second-order kinetic model adjusted well to the experimental data. The PECs release approximately 11.80 μg/mg Ag+ (66%) compared to the initial adsorbed AgNPs content (17.18 μg/mg) after 7200 min at pH 2.0. The PECs present low swelling degrees (between 130 and 150%), supporting high stability in water. PEC/AgNPs composites promote significant bactericidal activity toward Staphylococcus aureus and Escherichia coli between 0.25 and 0.5 mg/mL. This study shows a new strategy to create hybrid polysaccharide/AgNPs composites. PECs can stabilize the AgNPs and release Ag+ ions, supporting antimicrobial materials.
•Polyelectrolyte complexes (PECs) were synthesized using a green solvent.•95% of the citrate-capped silver nanoparticles were adsorbed on PECs' surface.•Citrate-capped silver nanoparticles are visible on PECs.•Hybrid materials present low heparin release at simulated fluids.•The Citrate-capped silver nanoparticles sorption is faster than the Ag+ ion release.
Anopheles darlingi is the principal neotropical malaria vector, responsible for more than a million cases of malaria per year on the American continent. Anopheles darlingi diverged from the African ...and Asian malaria vectors ∼100 million years ago (mya) and successfully adapted to the New World environment. Here we present an annotated reference A. darlingi genome, sequenced from a wild population of males and females collected in the Brazilian Amazon. A total of 10 481 predicted protein-coding genes were annotated, 72% of which have their closest counterpart in Anopheles gambiae and 21% have highest similarity with other mosquito species. In spite of a long period of divergent evolution, conserved gene synteny was observed between A. darlingi and A. gambiae. More than 10 million single nucleotide polymorphisms and short indels with potential use as genetic markers were identified. Transposable elements correspond to 2.3% of the A. darlingi genome. Genes associated with hematophagy, immunity and insecticide resistance, directly involved in vector-human and vector-parasite interactions, were identified and discussed. This study represents the first effort to sequence the genome of a neotropical malaria vector, and opens a new window through which we can contemplate the evolutionary history of anopheline mosquitoes. It also provides valuable information that may lead to novel strategies to reduce malaria transmission on the South American continent. The A. darlingi genome is accessible at www.labinfo.lncc.br/index.php/anopheles-darlingi.
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