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1.
J Steroid Biochem Mol Biol ; 232: 106361, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37419395

RESUMO

Over the past decades, a remarkable number of scientific studies supported the correlation between an adequate dietary intake of phytosterols (PS) and the reduced risk of cardiovascular diseases. PS are known to inhibit the intestinal absorption of cholesterol, thus promoting the reduction of the low-density lipoproteins (LDL) amount in the bloodstream. Despite the fact that a non-negligible atherogenicity was recognized to PS, thus requiring a careful risk-benefits assessment for plant sterol supplementation, the potential role of PS as cholesterol-lowering agents has been contributing to the spreading awareness of the health benefits associated with the consumption of plant-based foods. In recent years, this has been fueling the market of innovative vegetable products, such as microgreens. Surprisingly, the recent literature concerning microgreens exhibited the lack of studies focusing on the characterization of PS. To fill this gap, a validated analytical method based on the hyphenation of gas chromatography and tandem mass spectrometry is proposed here for the quantitative analysis of eight phytosterols, namely ß-sitosterol, campesterol, stigmasterol, brassicasterol, isofucosterol, and cholesterol, lathosterol and lanosterol. The method was exploited for the characterization of the PS content in 10 microgreen crops, i.e., chia, flax, soybean, sunflower, rapeseed, garden cress, catalogna chicory, endive, kale and broccoli raab. Finally, these results were compared to the PS content of mature forms of kale and broccoli raab. A remarkable amount of PS was detected in chia, flax, rapeseed, garden cress, kale, and broccoli raab microgreens. 100 g (wet weight) of these microgreen crops were found to contain from 20 to 30 mg of the investigated PS. Interestingly, in the case of kale and broccoli raab microgreens, the overall PS content was higher than the one measured in the edible parts of the corresponding mature forms. Additionally, a symmetric change of the PS inner profile was observed between the two growth stages of the latter two crops. Here, the overall decrease of the PS sterol content in the mature forms was associated with the increase of the relative amount of ß-sitosterol and campesterol at the expense of minor PS species, such as brassicasterol.


Assuntos
Fitosteróis , Esteróis , Espectrometria de Massas em Tandem , Cromatografia Gasosa-Espectrometria de Massas , Fitosteróis/química , Colesterol , Sitosteroides
2.
Sci Rep ; 10(1): 4739, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32179790

RESUMO

The melting of glaciers and ice sheets is nowadays considered a symbol of climate change. Many complex mechanisms are involved in the melting of ice, and, among these processes, surface darkening due to organic material on bare ice has recently received attention from the scientific community. The presence of microbes on glaciers has been shown to decrease the albedo of ice and promote melting. Despite several studies from the Himalaya, Greenland, Andes, and Alaska, no quantitative studies have yet been conducted in the European Alps. In this paper, we made use of DNA sequencing, microscopy and field spectroscopy to describe the nature of glacier algae found at a glacier (Vadret da Morteratsch) of the European Alps and to evaluate their effect on the ice-albedo feedback. Among different algal species identified in the samples, we found a remarkable abundance of Ancylonema nordenskioeldii, a species that has never previously been quantitatively documented in the Alps and that dominates algal blooms on the Greenland Ice Sheet. Our results show that, at the end of the ablation season, the concentration of Ancylonema nordenskioeldii on the glacier surface is higher than that of other algal species (i.e. Mesotaenium berggrenii). Using field spectroscopy data, we identified a significant correlation between a reflectance ratio (750 nm/650 nm) and the algae concentration. This reflectance ratio could be useful for future mapping of glacier algae from remote sensing data exploiting band 6 (740 nm) and band 4 (665 nm) of the MultiSpectral Instrument (MSI) on board Sentinel-2 satellite. Here we show that the biological darkening of glaciers (i.e. the bioalbedo feedback) is also occurring in the European Alps, and thus it is a global process that must be taken into account when considering the positive feedback mechanisms related to glacier melting.

3.
Water Res ; 159: 122-134, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31082643

RESUMO

This study aims at testing the effectiveness of Positive Matrix Factorization in characterizing groundwater and surface water quality, in terms of identifying main hydrochemical features and processes (natural and anthropogenic) that govern them. This method is applied in a hydro-system featured by a strong interrelation between groundwater and surface water and highly impacted by agricultural activities. Therefore, a holistic approach considering groundwater together with the surface water bodies, consisting in lake, several rivers and springs, was used. Multivariate statistical analysis, in particular Factor Analysis, has been proved to be effective in elaborating and interpreting water quality data highlighting the information carried within them, but it presents some limitations: it does not consider data uncertainty and it groups variables which are correlated positively and negatively. Moreover, in some cases the resulting factors are not clearly interpretable, describing each one various overlapping features/processes. Here, Positive Matrix Factorization is applied to groundwater and surface water quality data, and the results are compared to those obtained through a Factor Analysis in terms of both factor profiles and their spatial distribution through a GIS approach. Results of isotopes analysis are used to validate PMF output and support interpretation. Positive Matrix Factorization allows to consider data uncertainty and the solution respects two positivity constraints, based on the concept of chemical mass balance, which leads to a more environmentally interpretable solution. Results show that Positive Matrix Factorization identifies five different factors reflecting main features and natural and anthropogenic processes affecting the study area: 1) surface water used for irrigation, 2) groundwater subjected to reducing processes at advanced stages, 3) groundwater subjected to reducing processes at early stages, 4) groundwater residence time and 5) the effects of the agricultural land use on both groundwater and surface water. Positive Matrix Factorization leads to a more detailed understanding of the studied system as compared to Factor Analysis which identifies only three factors with overlapping information. Based on the results of this study, Positive Matrix Factorization could be a useful technique to perform groundwater and surface water quality characterization and to reach a deeper understanding of the phenomena that govern water chemistry.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Sistemas de Informação Geográfica , Rios , Qualidade da Água
4.
Br J Cancer ; 88(7): 996-1003, 2003 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-12671694

RESUMO

The Pretargeted Antibody-Guided RadioImmunoTherapy (PAGRIT) method is based on intravenous, sequential administration of a biotinylated antibody, avidin/streptavidin and (90)Y-labelled biotin. The hybridoma clone producing the monoclonal antitenascin antibody BC4, previously used for clinical applications, was found not suitable for further development because of the production of an additional, nonfunctional light chain. In order to solve this problem, the new cST2146 hybridoma clone was generated. The monoclonal antibody ST2146, produced by this hybridoma, having the same specificity as BC4 but lacking the nonfunctional light chain, was characterised. ST2146 was found able to bind human tenascin at an epitope strictly related, if not identical, to the antigenic epitope of BC4. It showed, compared to BC4, higher affinity and immunoreactivity and similar selectivity by immunohistochemistry. Biodistribution studies of biotinylated ST2146 and three other monoclonal antitenascin antibodies showed for ST2146 the highest and more specific tumour localisation in HT29-grafted nude mice. On the overall, ST2146 appears to be a good alternative to BC4 for further clinical development of PAGRIT.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias Experimentais/radioterapia , Radioimunoterapia , Tenascina/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacocinética , Afinidade de Anticorpos , Especificidade de Anticorpos , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Tecidual
5.
Int J Immunopharmacol ; 14(6): 1061-8, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1428361

RESUMO

ST 789 is a new synthetic compound characterized by an amino acidic group joined to the N9 position of the hypoxanthine ring, which has been shown recently to have immunomodulating properties and minimal toxicity. The drug has been reported to protect immunosuppressed mice from microbial infections and tumour growth, and to restore the mitogen-induced proliferation of splenocytes from immunosuppressed young mice. In this study, we show that in vitro addition of ST 789 is able to markedly augment the sheep red blood cells (SRBC) phagocytosis by PEC, and to potentiate the cytotoxic activity of peritoneal exudate (PE) macrophages (M phi) vs the L-M tumour cell line. We also found that ST 789 enhanced the rIFN-gamma-induced NO2- release from cultured PE M phi. Similarly, in vitro addition of ST 789 to the latter cultures significantly increased the production of interleukin 1 (IL-1) and tumour necrosis factor (TNF) induced by lipopolysaccharide (LPS). These studies demonstrate that ST 789 is a potent phagocyte activator for the induction of cytokine release, phagocytosis and cytotoxic activity against tumour cells in vitro.


Assuntos
Adjuvantes Imunológicos/farmacologia , Arginina/análogos & derivados , Hipoxantinas/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Animais , Arginina/farmacologia , Linhagem Celular , Citotoxicidade Imunológica/efeitos dos fármacos , Exsudatos e Transudatos/citologia , Interleucina-1/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos C3H , Óxido Nítrico/metabolismo , Cavidade Peritoneal/citologia , Fagocitose/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese
6.
Parassitologia ; 27(3): 303-11, 1985 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-3870647

RESUMO

In the period March 1983 - March 1984 a parasitological survey was carried out on 103 foxes killed in the Forli province (Italy). The parasites identified were: Toxocara canis (45.6%); Uncinaria stenocephala (14.6%); Mesocestoides lineatus (9.7%); Dipylidium caninum (2.9%); Taenia crassiceps (2.9%); Trichuris vulpis (2.9%). Out of all the cestodes found in 7 animals the authors identified only genus Taenia since their preservation conditions were not optimal. Other 13 subjects contained many cestodes similar to T. hydatigena, but considerably shorter in the mean length (20 cm vs 200). In a fecal sample the authors found a species of coccidium whose features do not correspond to any of those described in foxes, therefore it was called Eimeria sp. Finally, the autopsies' results were compared with coprological ones in order to asses their reliability.


Assuntos
Raposas/parasitologia , Animais , Fezes/parasitologia , Itália
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