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1.
Mar Environ Res ; 167: 105287, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33657495

RESUMO

The role of the human-made structures in coastal ecosystems can determine the spatial distribution or patterns of spatial abundances of marine organisms. To contribute to the understanding of linkages between different components of habitats (i.e. natural and artificial structures), we explored the role of type of larval development (planktotrophic vs. non-planktotrophic) on patterns of spatial variation of gastropods on rocky shores, elucidating the possible responsibility of habitat fragmentation on their distribution. Obtained results suggest that habitat fragmentation affects differently the patterns of variability of species with different types of larval development. Namely, fragmentation caused by artificial structures mostly influence variability of species with non-planktotrophic development. Moreover, although abundance of the species with non-planktotrophic development varied at small spatial scales, suggesting that processes operating at this scale are likely the main drivers of their distribution, changes in species variability were not associated with differences in species abundance among habitats.


Assuntos
Ecossistema , Gastrópodes , Animais , Organismos Aquáticos , Humanos
2.
Micron ; 80: 112-21, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26520255

RESUMO

The diagenetic history of calcareous fossils is required for their application as palaeoenvironmental indicators. In this study, cathodoluminescence-microscopy (CL microscopy) and back scatter electron image-energy dispersive X-ray spectroscopy (BSE-EDS microscopy) were applied to Pliocene rhodoliths from the Azores Archipelago (NE Atlantic) in order to gain additional insight regarding the trace element content distribution throughout the algae thalli, and to ascertain palaeoenvironmental interpretations. Two types of luminescence were obtained: (1) high and (2) low luminescence. Rhodoliths with high luminescence are related with high concentrations of Mn(2+) in seawater and low luminescence rhodoliths are related with low concentrations of Mn(2+) in seawater. When the rhodoliths were deposited at about 4.0-4.5 Ma, the shoreline configuration of Santa Maria Island was much different than today. The influence of volcanic activity due to the extrusion of lavas and associated products and/or the presence of active shallow-water hydrothermal vents, was reflected in the sea water chemistry, with penecontemporaneous palaeoshores of the island featuring a high sea water concentration of Mn(2+), which mirrored on the rhodolith Mn(2+) high concentration. By contrast, rhodoliths located about 2.8 and 2.9 km from the shore, in areas with low seawater Mn(2+) concentration, had low luminescence, reflecting the low Mn(2+) concentration in seawater. Rhodoliths chemical data and the geological history of the island proved to be congruent with the palaeogeographical reconstruction of Santa Maria Island at the time of the formation of the rhodoliths.


Assuntos
Fósseis , Sedimentos Geológicos/química , Medições Luminescentes/métodos , Rodófitas/química , Oligoelementos/análise , Açores , Análise Espectral/métodos
3.
Biomater Sci ; 3(4): 581-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26222417

RESUMO

We propose a novel hanging spherical drop system for anchoring arrays of droplets of cell suspension based on the use of biomimetic superhydrophobic flat substrates, with controlled positional adhesion and minimum contact with a solid substrate. By facing down the platform, it was possible to generate independent spheroid bodies in a high throughput manner, in order to mimic in vivo tumour models on the lab-on-chip scale. To validate this system for drug screening purposes, the toxicity of the anti-cancer drug doxorubicin in cell spheroids was tested and compared to cells in 2D culture. The advantages presented by this platform, such as feasibility of the system and the ability to control the size uniformity of the spheroid, emphasize its potential to be used as a new low cost toolbox for high-throughput drug screening and in cell or tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Avaliação Pré-Clínica de Medicamentos/instrumentação , Ensaios de Triagem em Larga Escala/métodos , Esferoides Celulares/citologia , Engenharia Tecidual/métodos , Antineoplásicos/química , Antineoplásicos/farmacologia , Biomimética , Biotecnologia , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Humanos
5.
Mar Environ Res ; 94: 72-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24374052

RESUMO

Several studies have suggested that communities associated with artificial substrata support more non-indigenous species (NIS) than natural habitats, and may function as corridors for their expansion. Our study focused on the role of substrate type, timing and duration of submersion as determinants of fouling assemblage. We used plates made of basalt, concrete or fibreglass, to assess early, i.e., 3 months, and late, i.e., 12 months, succession in benthic communities. To assess spatial and temporal variability of the results, sampling was performed at 2 locations and the experiment was repeated in two seasons of the year. Our results showed that the timing and duration of submersion affected the number and percent cover of natives and NIS, as well as assemblage composition. Moreover, the present study showed no support for the hypothesis that marine NIS are more abundant on artificial substrata, as neither of the two artificial substrata tested supported a greater number of NIS compared to basalt (the natural substratum). Overall, fibreglass presented the most different benthic assemblage composition, supporting the fact that the extent and nature of the observed differences varied not only between natural and artificial substrata, but also according to the type of artificial habitat considered. Thus, our results are in agreement with previous studies that stated that appropriate strategies for environmental management should integrate ecological assessment in order to maintain natural patterns of distribution and abundance of organisms, scales of variability and relevant ecological processes.


Assuntos
Ecossistema , Espécies Introduzidas , Animais , Biodiversidade , Fatores de Tempo
6.
Nat Prod Res ; 27(7): 665-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22591127

RESUMO

The content of total lipids and the fatty acid (FA) profile were determined for eight macroalgae (Cystoseira abies-marina, Fucus spiralis, Chaetomorpha pachynema, Codium elisabethae, Porphyra sp., Osmundea pinnatifida, Pterocladiella capillacea and Sphaeroccoccus coronopifolius). Total lipids were extracted using a solvent mixture of methanol/chloroform (2/1, v/v) and further derivatised to FA methyl esters (FAME). The analyses of FAME samples were performed by gas chromatography coupled to a flame ionisation detector. The total lipid content ranged from 0.06 to 3.54 g (per 100 g). The most abundant saturated FA were palmitic (C16:0) and myristic (C14:0), while oleic (C18:1 n-9) was the dominant monounsaturated acid. All seaweeds contained linoleic FA (C18:2 n-6). The α-linolenic (C18:3 n-3) and eicosapentaenoic (20:5 n-3) acids were present only in Porphyra sp. (3.34% ± 0.13) and C. pachynema (0.47% ± 0.12), respectively. The n-6/n-3 and h/H ratios were low, suggesting a high nutritional value of the algae studied.


Assuntos
Ácidos Graxos/análise , Alga Marinha/química , Cromatografia Gasosa , Ácido Eicosapentaenoico/análise , Ácido Linoleico/análise , Ácido alfa-Linolênico/análise
7.
Braz J Med Biol Res ; 44(11): 1177-83, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22052375

RESUMO

The aim of this study was to determine the impact of antiretroviral therapy on the lipid profile of human immunodeficiency virus (HIV) patients before and after the initiation of highly active antiretroviral therapy (HAART). This was a cross-sectional analysis of patients receiving HAART at a reference center in Belo Horizonte, Brazil, on the basis of medical records from 2002 to 2006. Patients were included if they had at least one lipid test or a clinical or laboratory diagnosis of dyslipidemia/lipodystrophy. Among the 692 patients, 620 met the eligibility criteria. The majority were males (66.5%), middle age (average 39 years), had a low educational level (60.4%), and low income (51.0%). HAART duration ranged from 11 days to 4.6 years, with a mean of 28.6 months (SD = ± 470.19 days). The prevalence of dyslipidemia/lipodystrophy nearly tripled (11.3% pre- and 32.4% post-HAART). Dyslipidemia was associated with older age (P = 0.007), nucleoside reverse transcriptase inhibitor (NRTI) + protease inhibitor (PI) regimens (P = 0.04), NRTI + non-NRTI (NNRTI) regimens (P = 0.026), the use of stavudine (d4T) in any regimen (P = 0.002) or in NRTI-based regimens (P = 0.006), and longer exposure to HAART (P < 0.000). In addition, there was no correlation between dyslipidemia and gender (P = 0.084). Only 2.0% of the patients received treatment for dyslipidemia during the trial. These results show a need for continuous monitoring of patients under antiretroviral therapy, particularly those using NRTI-based regimens, especially when combined with d4T and PIs. Secondly, interventions should be developed to correct metabolic changes.


Assuntos
Dislipidemias/epidemiologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/efeitos adversos , Lipodistrofia/epidemiologia , Inibidores da Transcriptase Reversa/efeitos adversos , Estavudina/efeitos adversos , Adolescente , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Brasil/epidemiologia , Estudos Transversais , Quimioterapia Combinada/efeitos adversos , Dislipidemias/induzido quimicamente , Feminino , Humanos , Lipodistrofia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Resultado do Tratamento , Adulto Jovem
8.
Braz. j. med. biol. res ; 44(11): 1177-1183, Nov. 2011. tab
Artigo em Inglês | LILACS | ID: lil-604282

RESUMO

The aim of this study was to determine the impact of antiretroviral therapy on the lipid profile of human immunodeficiency virus (HIV) patients before and after the initiation of highly active antiretroviral therapy (HAART). This was a cross-sectional analysis of patients receiving HAART at a reference center in Belo Horizonte, Brazil, on the basis of medical records from 2002 to 2006. Patients were included if they had at least one lipid test or a clinical or laboratory diagnosis of dyslipidemia/lipodystrophy. Among the 692 patients, 620 met the eligibility criteria. The majority were males (66.5 percent), middle age (average 39 years), had a low educational level (60.4 percent), and low income (51.0 percent). HAART duration ranged from 11 days to 4.6 years, with a mean of 28.6 months (SD = ± 470.19 days). The prevalence of dyslipidemia/lipodystrophy nearly tripled (11.3 percent pre- and 32.4 percent post-HAART). Dyslipidemia was associated with older age (P = 0.007), nucleoside reverse transcriptase inhibitor (NRTI) + protease inhibitor (PI) regimens (P = 0.04), NRTI + non-NRTI (NNRTI) regimens (P = 0.026), the use of stavudine (d4T) in any regimen (P = 0.002) or in NRTI-based regimens (P = 0.006), and longer exposure to HAART (P < 0.000). In addition, there was no correlation between dyslipidemia and gender (P = 0.084). Only 2.0 percent of the patients received treatment for dyslipidemia during the trial. These results show a need for continuous monitoring of patients under antiretroviral therapy, particularly those using NRTI-based regimens, especially when combined with d4T and PIs. Secondly, interventions should be developed to correct metabolic changes.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Dislipidemias/epidemiologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/efeitos adversos , Lipodistrofia/epidemiologia , Inibidores da Transcriptase Reversa/efeitos adversos , Estavudina/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Brasil/epidemiologia , Estudos Transversais , Quimioterapia Combinada/efeitos adversos , Dislipidemias/induzido quimicamente , Lipodistrofia/induzido quimicamente , Estatísticas não Paramétricas , Resultado do Tratamento
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