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1.
Nutrients ; 14(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35011095

RESUMO

Saffron (Crocus sativus L.) is known as the most expensive spice. C. sativus dried red stigmas, called threads, are used for culinary, cosmetic, and medicinal purposes. The rest of the flower is often discarded, but is now being used in teas, as coloring agents, and fodder. Previous studies have attributed antioxidant, anti-inflammatory, hepatoprotective, neuroprotective, anti-depressant, and anticancer properties to C. sativus floral bio-residues. The aim of this study is to assess C. sativus flower water extract (CFWE) for its effects on hemoglobin, brush boarder membrane (BBM) functionality, morphology, intestinal gene expression, and cecal microbiome in vivo (Gallus gallus), a clinically validated model. For this, Gallus gallus eggs were divided into six treatment groups (non-injected, 18 Ω H2O, 1% CFWE, 2% CFWE, 5% CFWE, and 10% CFWE) with n~10 for each group. On day 17 of incubation, 1 mL of the extracts/control were administered in the amnion of the eggs. The amniotic fluid along with the administered extracts are orally consumed by the developing embryo over the course of the next few days. On day 21, the hatchlings were euthanized, the blood, duodenum, and cecum were harvested for assessment. The results showed a significant dose-dependent decrease in hemoglobin concentration, villus surface area, goblet cell number, and diameter. Furthermore, we observed a significant increase in Paneth cell number and Mucin 2 (MUC2) gene expression proportional to the increase in CFWE concentration. Additionally, the cecum microbiome analysis revealed C. sativus flower water extract altered the bacterial populations. There was a significant dose-dependent reduction in Lactobacillus and Clostridium sp., suggesting an antibacterial effect of the extract on the gut in the given model. These results suggest that the dietary consumption of C. sativus flower may have negative effects on BBM functionality, morphology, mineral absorption, microbial populations, and iron status.


Assuntos
Ceco/microbiologia , Crocus/química , Flores/química , Microbioma Gastrointestinal/efeitos dos fármacos , Microvilosidades/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Galinhas
2.
Atmos Chem Phys ; 21: 1-19, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34987561

RESUMO

Questions about how emissions are changing during the COVID-19 lockdown periods cannot be answered by observations of atmospheric trace gas concentrations alone, in part due to simultaneous changes in atmospheric transport, emissions, dynamics, photochemistry, and chemical feedback. A chemical transport model simulation benefiting from a multi-species inversion framework using well-characterized observations should differentiate those influences enabling to closely examine changes in emissions. Accordingly, we jointly constrain NO x and VOC emissions using well-characterized TROPOspheric Monitoring Instrument (TROPOMI) HCHO and NO2 columns during the months of March, April, and May 2020 (lockdown) and 2019 (baseline). We observe a noticeable decline in the magnitude of NO x emissions in March 2020 (14 %-31 %) in several major cities including Paris, London, Madrid, and Milan, expanding further to Rome, Brussels, Frankfurt, Warsaw, Belgrade, Kyiv, and Moscow (34 %-51 %) in April. However, NO x emissions remain at somewhat similar values or even higher in some portions of the UK, Poland, and Moscow in March 2020 compared to the baseline, possibly due to the timeline of restrictions. Comparisons against surface monitoring stations indicate that the constrained model underrepresents the reduction in surface NO2. This underrepresentation correlates with the TROPOMI frequency impacted by cloudiness. During the month of April, when ample TROPOMI samples are present, the surface NO2 reductions occurring in polluted areas are described fairly well by the model (model: -21 ± 17 %, observation: -29 ± 21 %). The observational constraint on VOC emissions is found to be generally weak except for lower latitudes. Results support an increase in surface ozone during the lockdown. In April, the constrained model features a reasonable agreement with maximum daily 8 h average (MDA8) ozone changes observed at the surface (r = 0.43), specifically over central Europe where ozone enhancements prevail (model: +3.73 ± 3.94 %, + 1.79 ppbv, observation: +7.35 ± 11.27 %, +3.76 ppbv). The model suggests that physical processes (dry deposition, advection, and diffusion) decrease MDA8 surface ozone in the same month on average by -4.83 ppbv, while ozone production rates dampened by largely negative J NO 2 [ NO 2 ] - k NO + O 3 [ NO ] [ O 3 ] become less negative, leading ozone to increase by +5.89 ppbv. Experiments involving fixed anthropogenic emissions suggest that meteorology contributes to 42 % enhancement in MDA8 surface ozone over the same region with the remaining part (58 %) coming from changes in anthropogenic emissions. Results illustrate the capability of satellite data of major ozone precursors to help atmospheric models capture ozone changes induced by abrupt emission anomalies.

3.
Biomaterials ; 160: 15-23, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29353104

RESUMO

Computed tomography (CT) with contrast plays an important role as a clinical diagnostic tool but still has a limited diagnostic range. In this work, we developed a novel injectable iodine-based small molecule CT contrast agent, even can be used for bile duct diagnostics. The bile duct diagnosable CT contrast agent (BDICA) is synthesized with 5-amino-2,4,6-triiodoisophthaloyl dichloride (ATIPC), tromethamine and lactobionic acid (LBA) for asialoglycoprotein receptor (ASGPR) targeted delivery via receptor-mediated endocytosis and transport to the bile canaliculi. Specific binding to the ASGPRs was confirmed by in vitro cellular uptake in HepG2 cells (ASGPR positive) and HCT 116 cells (ASGPR negative). Compared to iohexol, BDICA has equal in vivo distribution and a 13-fold iodine increase in content was observed in bile juice after BDICA injection. The radiopaque contrast effect in the bile duct has been clearly shown in in vivo CT scans. Furthermore, within 36 h, 91.3% of the BDICA was eliminated without organ damage, which verified the overall safety of the contrast agent. BDICA not only provides sufficient contrast images similar to iohexol, but also provides superior images of the bile duct. Based on recent studies, it has been shown that BDICA is a promising, safe and effective contrast agent for CT imaging of the organs and soft tissues, including the bile duct.


Assuntos
Ductos Biliares/diagnóstico por imagem , Meios de Contraste/síntese química , Iodo/química , Animais , Meios de Contraste/efeitos adversos , Meios de Contraste/metabolismo , Corantes Fluorescentes/química , Humanos , Iodo/efeitos adversos , Iodo/metabolismo , Masculino , Imagem Óptica/métodos , Ratos Sprague-Dawley , Distribuição Tecidual , Tomografia Computadorizada por Raios X
4.
J Anim Ecol ; 80(3): 577-85, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21226710

RESUMO

1. Much work on ecological consequences of community assembly history has focused on the formation of history-induced alternative stable equilibria. We hypothesize that assembly history may affect not only community composition but also population dynamics, with assembled communities differing in species composition potentially residing in different dynamical states. 2. We provided an empirical test of the aforementioned hypothesis using a laboratory microcosm experiment that manipulated both the colonization order of three bacterivorous protist species in the presence of a protist predator and environmental productivity. 3. Both priority effects and random divergence emerged, resulting in two different community compositional states: one characterized by the dominance of one prey species and the other by the extinction of the same prey. While communities in the former state exhibited noncyclic dynamics, the majority of communities in the latter state exhibited cyclic dynamics driven by the interaction between another prey and the predator. 4. Temporal variability of total prey community biovolume consequently differed among communities with different histories. 5. Changing productivity altered priority effects on the structure and dynamics of communities experiencing only certain histories. 6. Our results support the dual (compositional and dynamical) consequences of assembly history and emphasize the importance of incorporating the dynamical view into the field of community assembly.


Assuntos
Biota , Animais , Cilióforos , Cadeia Alimentar , Densidade Demográfica , Dinâmica Populacional , Tetrahymena pyriformis , Tetrahymenina
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