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51.
Michel D. Gianeti Francisco M. Santana Leandro Yokota Jonas E. Vasconcelos June F. Dias Rosangela P. Lessa 《Journal of fish biology》2019,94(3):481-488
We collected 729 Hypanus guttatus from the northern coast of the state of Rio Grande do Norte (RN), of which 196 were used to estimate age and growth. Ninety-five were male (12.7 to 57.0 cm disc width; WD) and 101 were female (13.0 to 88.5 cm WD); females were significantly larger than males. Cross sections of vertebrae showed band-pairs ranging from 0 to > 14 in females and from 0 to 9 in males. New-borns presented an opaque edge at birth in vertebrae without a birthmark. The average percentage of error (APE; %E) for the entire sample provided evidence that ages were repeatable. The mean monthly marginal increment (IM) indicates annual band-pair formation from August to November. The annual cycle model for one band-pair deposition provided the best fit to data based on the AIC, with peaks between August and October, similar to that found in the IM analysis, suggesting an annual formation pattern. A multi-model approach that included four models based on the observed mean WD at age indicated a modified von Bertalanffy growth model as the best for describing the species growth: W0 (WD at birth) = 14.6 cm for both sexes; females W∞ = 98.61 cm (95% CI = 87.34–114.61 cm); k = 0.112 year−1 (CI = 0.086–0.148 year−1); males W∞ = 60.22 cm (CI = 55.66–65.35 cm); k = 0.219 year−1 (CI = 0.185–0.276 year−1). The age-at-maturity in males and females is 5 years and 7 years, respectively. The age composition shows that most (84%) specimens were aged 0 to 2 years. The information provided here is essential for analytical assessments of H. guttatus, which is subject to significant fishing pressure mainly on new-borns and juveniles. 相似文献
52.
Trichoderma species conidiate in response to blue light, however, unlike in the blue-light model fungus Neurospora crassa, conidiation in Trichoderma spp. has been considered to be non-circadian. In this study we uncovered evidence for circadian conidiation in Trichoderma pleuroticola and identified orthologues of the key N. crassa clock components, wc-1 (blr-1) and frq. 相似文献
53.
In vitro activity of propyl gallate-azole drug combination against fluconazole- and itraconazole-resistant Candida albicans strains 总被引:1,自引:0,他引:1
AIMS: The influence of an antioxidant, propyl gallate (PG), on the in vitro antifungal activity of itraconazole and fluconazole, was investigated to determine whether PG could increase the antifungal activity and reduce strain resistance. METHODS AND RESULTS: Susceptibility tests were performed against azole-resistant isolates of Candida albicans by the microbroth dilution method in the presence of PG at 400 microg ml-1. PG-triazole combination brought about a marked reduction of inhibitory azole concentration. In particular, the MIC90 for itraconazole and fluconazole dropped from 1 microg ml-1 to 0.125 microg ml-1 and from > 64 microg ml-1-8 microg ml-1, respectively. CONCLUSION: It is likely that more than one mechanism is involved in the above synergistic interaction, including effects of PG on ATP synthesis, thus reducing the ABC transporters activity, or an effect on the target of azole, i.e. the P-450 cytochrome. SIGNIFICANCE AND IMPACT OF THE STUDY: The PG-triazole combination may have a role in future topical antifungal strategies but other studies are warranted. 相似文献
54.
Carlos E. Valdivia Javier A. Simonetti Carolina A. Henríquez 《Biodiversity and Conservation》2006,15(5):1845-1856
We studied the pollination and reproductive success in continuous and fragmented populations of Lapageria rosea, a self-compatible plant endemic to temperate forests of Chile. Pollinator abundance, visitation rates, flower abundance,
nectar volume and concentration, pollen germination and fruit and seed production, were compared between continuous forest
of 145 ha and four forest fragments of 6, 3, 3, and 1 ha respectively, surrounded by mature pine plantations of Pinus radiata. Flower abundance was lower in three out of four forest fragments relative to continuous forest. Nectar volume and sugar
concentration did not differ between flowers in the two habitats. Pollinators of L. rosea, the hummingbird Sephanoides sephaniodes and bumblebee Bombus dahlbomii were less abundant and visited flowers of L. rosea at lower rates in fragments than in continuous forest. In addition, in vitro rates of pollen germination were lower for flowers in forest fragments. The number of seeds per fruit was also lower in forest
fragments. We suggest that fragmentation affects the reproductive success of L. rosea, lowering the total numbers of seeds produced and possibly compromising long term persistence of fragmented populations. 相似文献
55.
Amarildo Emanuel Correia Jordão Bruno Cogliati Bernard Ernesto Jensch-Junior Leandro Nogueira Pressinotti Osório Miguel Parra Francisco Javier Hernandez-Blazquez José Roberto Machado Cunha da Silva 《Polar Biology》2007,30(3):387-390
The Notothenia coriiceps liver is commonly infected with parasites, reducing the hepatic mass and inducing the regeneration. In order to better understand
the effect of nutrient influx on hepatic regeneration at 0°C, a usual mammal hepatotrophic factor (HF) solution was injected
into ten fish (HF group), while ten fish were injected with saline solution (control), twice a day, for 15 days. The liver
and carcass weight were measured, and samples were obtained for histological studies. The HF group presented a higher liver/carcass
weight (62.5%) than control group. This increase in liver mass was due mainly to hepatocytes hypertrophy, including nuclear
size increase and cytoplasmic inclusions of glycogen. Hyperplasia is also observed, although to a lesser extent. The hepatic
reaction to HF in Antarctic fish was here demonstrated for the first time, helping to understand the liver response to seasonal
nutrient. 相似文献
56.
Toxicity,behavior impairment,and repellence of essential oils from pepper‐rosmarin and patchouli to termites 下载免费PDF全文
Leandro Bacci Janaína K.A. Lima Ana Paula A. Araújo Arie F. Blank Indira M.A. Silva Abraão A. Santos Ane C.C. Santos Péricles B. Alves Marcelo C. Picanço 《Entomologia Experimentalis et Applicata》2015,156(1):66-76
Plant essential oils are potential sources of insecticidal compounds, but have rarely been explored for their effect on termites. In the present study, we assessed the chemical composition of essential oils of Lippia sidoides Cham. (pepper‐rosmarin; Verbenaceae) and Pogostemon cablin (Blanco) Benth. (patchouli; Lamiacaeae) and evaluated their toxicity, behavioral impairment, and repellence to termite species of the genera Amitermes and Microcerotermes (Isoptera: Termitidae: Termitinae). The main components of essential oils of L. sidoides and P. cablin were thymol (44.6%) and patchouli alcohol (36.6%), respectively. The essential oil of P. cablin was most potent against Amitermes cf. amifer Silvestri and had the lowest LD50 (0.63 μg mg?1). There was no difference in toxicity for Microcerotermes indistinctus Mathews between the essential oils of L. sidoides (LD50 = 1.49 μg mg?1) and P. cablin (LD50 = 1.67 μg mg?1). Pogostemon cablin essential oil was the most toxic to M. indistinctus (LC50 = 0.32 μl ml?1) and A. cf. amifer (LC50 = 0.29 μl ml?1). The essential oils analyzed exhibited high toxicity and repellence to the termites, in addition to reducing behavioral interactions among individuals, thus constituting potential termiticides. 相似文献
57.
58.
Sayani Dasgupta Leandro M. Castro Russell Dulman Ciyu Yang Marion Schmidt Emer S. Ferro Lloyd D. Fricker 《PloS one》2014,9(7)
The proteasome cleaves intracellular proteins into peptides. Earlier studies found that treatment of human embryonic kidney 293T (HEK293T) cells with epoxomicin (an irreversible proteasome inhibitor) generally caused a decrease in levels of intracellular peptides. However, bortezomib (an antitumor drug and proteasome inhibitor) caused an unexpected increase in the levels of most intracellular peptides in HEK293T and SH-SY5Y cells. To address this apparent paradox, quantitative peptidomics was used to study the effect of a variety of other proteasome inhibitors on peptide levels in HEK293T and SH-SY5Y cells. Inhibitors tested included carfilzomib, MG132, MG262, MLN2238, AM114, and clasto-Lactacystin β-lactone. Only MG262 caused a substantial elevation in peptide levels that was comparable to the effect of bortezomib, although carfilzomib and MLN2238 elevated the levels of some peptides. To explore off-target effects, the proteosome inhibitors were tested with various cellular peptidases. Bortezomib did not inhibit tripeptidyl peptidase 2 and only weakly inhibited cellular aminopeptidase activity, as did some of the other proteasome inhibitors. However, potent inhibitors of tripeptidyl peptidase 2 (butabindide) and cellular aminopeptidases (bestatin) did not substantially alter the peptidome, indicating that the increase in peptide levels due to proteasome inhibitors is not a result of peptidase inhibition. Although we cannot exclude other possibilities, we presume that the paradoxical increase in peptide levels upon treatment with bortezomib and other inhibitors is the result of allosteric effects of these compounds on the proteasome. Because intracellular peptides are likely to be functional, it is possible that some of the physiologic effects of bortezomib and carfilzomib arise from the perturbation of peptide levels inside the cell. 相似文献
59.
A new species of Lauraceae, Beilschmiedia vestita, from the Brazilian Atlantic forest, in Minas Gerais state, is described and illustrated. Its morphological similarities
and differences in relation to other species of Beilschmiedia are discussed. Distribution, habitat, phenology, etymology, and the IUCN Red List category are also provided. 相似文献
60.
Molecular evidence and clinical importance of β‐arrestins expression in patients with acromegaly 下载免费PDF全文
Maria Caroline Alves Coelho Marina Lipkin Vasquez Luiz Eduardo Wildemberg Mari C. Vázquez‐Borrego Luciana Bitana Aline Helen da Silva Camacho Débora Silva Liana Lumi Ogino Nina Ventura Leila Chimelli Raul M. Luque Leandro Kasuki Mônica R. Gadelha 《Journal of cellular and molecular medicine》2018,22(4):2110-2116
β‐arrestins seem to have a role in endocytosis and desensitization of somatostatin receptor subtype 2 (sst2) and could be associated with the responsiveness to somatostatin receptor ligands (SRL) in patients with acromegaly. To investigate the in vivo correlation between β‐arrestins 1 and 2 with sst2, sst5 and dopamine receptor subtype 2 (D2) expressions, and the association of β‐arrestins with response to first‐generation SRL and invasiveness in somatotropinomas. β‐arrestins 1 and 2, sst2, sst5 and D2 mRNA expressions were evaluated by quantitative real‐time RT‐PCR on tumoral tissue of 96 patients. Moreover, sst2 and sst5 protein expressions were also evaluated in 40 somatotropinomas by immunohistochemistry. Response to SRL, defined as GH <1 μg/l and normal IGF‐I levels, was assessed in 40 patients. The Knosp‐Steiner criteria were used to define invasiveness. Median β‐arrestin 1, β‐arrestin 2, sst2, sst5 and D2 mRNA copy numbers were 478; 9375; 731; 156 ; and 3989, respectively. There was a positive correlation between β‐arrestins 1 and 2 (R = 0.444, P < 0.001). However, no correlation between β‐arrestins and sst2, sst5 (mRNA and protein levels) or D2 was found. No association was found between β‐arrestins expression and SRL responsiveness or tumour invasiveness. Although previous data suggest a putative correlation between β‐arrestins and sst2, our data clearly indicated that no association existed between β‐arrestins and sst2, sst5 or D2 expression, nor with response to SRL or tumour invasiveness. Therefore, further studies are required to clarify whether β‐arrestins have a role in the response to treatment with SRL in acromegaly. 相似文献