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1.
Pharmaceutics ; 14(12)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36559132

RESUMO

This study aimed to determine the damage mechanisms caused by naturally targeted nanoarchaeosomes made of diether lipids from Halorubrum tebenquichense loaded with curcumin (CUR, nATC), which mediated photodynamic therapy (PDT) on A549 cells and on THP-1-macrophages, two cell types found in airway cancers. The effect of nATC- PDT on vessels modeled with a chicken embryo chorioallantoic membrane (CAM), after dropping the formulations on its surface covered with mucins, was also determined. nATCs are known to efficiently trap CUR for at least six months, constituting easy-to-prepare, stable formulations suitable for nebulization. CUR instead, is easily released from carriers such as liposomes made of ordinary phospholipids and cholesterol after a few weeks. Irradiated at 9 J/cm2, nATC (made of archaeolipids: Tween 80: CUR at 1:0.4:0.04 w:w, size 180 ± 40 nm, ζ potential -24 mV, 150 µg CUR/15 mg lipids/mL) was phototoxic (3.7 ± 0.5 µM IC50), on A549 cells after 24 h. The irradiation reduced mitochondrial membrane potential (ΔΨm), ATP levels and lysosomal functionalism, and caused early apoptotic death and late necrosis of A549 cells upon 24 h. nATC induced higher extra and intracellular reactive oxygen species (ROS) than free CUR. nATC-PDT impaired the migration of A549 cells in a wound healing assay, reduced the expression of CD204 in THP-1 macrophages, and induced the highest levels of IL-6 and IL-8, suggesting a switch of macrophage phenotype from pro-tumoral M2 to antitumoral M1. Moreover, nATC reduced the matrix metalloproteinases (MMP), -2 and -9 secretion, by A549 cells with independence of irradiation. Finally, remarkably, upon irradiation at 9 J/cm2 on the superficial vasculature of a CAM covered with mucins, nATC caused the vessels to collapse after 8 h, with no harm on non-irradiated zones. Overall, these results suggest that nebulized nATC blue light-mediated PDT may be selectively deleterious on superficial tumors submerged under a thick mucin layer.

2.
Ecotoxicol Environ Saf ; 243: 113984, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988383

RESUMO

Aquatic environments have been found to be contaminated with a variety of inorganic and organic UV filters. This includes novel nano-sized titanium dioxide (TiO2) composite particles, which have been increasingly developed and incorporated into commercial sunscreens in recent years. So far, relatively little is known about the effects of this novel class of UV filters on aquatic life. Therefore, this study aimed to determine and compare the toxicity of three such nanoparticulate TiO2 UV filters with different surface coatings, namely Eusolex® T-Avo (SiO2-coated), T-Lite™ SF (Al(OH)3/PDMS-coated), and Eusolex® T-S (Al2O3/stearic acid-coated) either alone, or in the presence of selected organic UV filters (octinoxate, avobenzone, octocrylene), toward fish using RTgill-W1 cell cultures as an in vitro experimental model. Besides standard exposure protocols, alternative approaches (i.e., exposure to water accommodated fractions (WAFs), hanging-drop exposure) were explored to account for nanoparticle (NP)-specific fate in the medium and obtain additional/complementary information on their toxicity in different conditions. The AlamarBlue, CFDA-AM and Neutral Red Retention (NR) assays were used to measure effects on different cellular endpoints. Transmission electron microscopy (TEM) was used to examine NP uptake. Our results showed that none of the TiO2 NP UV filters were cytotoxic at the concentrations tested (0.1-10 µg/mL; 24 h) but there were differences in their uptake by the cells. Thus, only the hydrophilic T-AVO was detected inside cells, but the hydrophobic T-Lite SF and T-S were not. In addition, our results show that the presence of NPs (or the used dispersant) tended to decrease organic UV filter toxicity. The level of combination effect depended on both NP-type (surface chemistry) and concentration, suggesting that the reduced toxicity resulted from reduced availability of the organic UV filters due to their adsorption to the NP surface. Thus, mixtures of TiO2 NP UV filters and organic UV filters may have a different toxicological profile compared to the single substances, but probably do not pose an increased hazard.


Assuntos
Brânquias , Nanocompostos , Animais , Peixes , Dióxido de Silício , Protetores Solares/química , Protetores Solares/toxicidade , Titânio/química , Titânio/toxicidade
3.
Environ Sci Pollut Res Int ; 29(22): 33885-33899, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35032268

RESUMO

Legacy effects of P in agricultural soils have been highlighted in recent literature. However, co-accumulation and release of organic P (Po) have often been ignored in current agro-environmental assessments. The mineralizable Po fraction has a potential to increase the activity of phosphate in pore water, increasing fertility or degrading water quality. In this study, the effects of agricultural management practices (fertilizer applied corn-soybean rotation cropland and dairy manure applied pasture) on the Po/phosphate ratio were investigated in P-rich (290-1232 mg kg-1) agricultural soils and adjacent ditchwater using experimental soil-water chemistry. The effect of agricultural management was significant on both Po and the Po/phosphate ratio in soil and adjacent ditchwater. The Po content, dominated by orthophosphate monoesters, in the manure-amended pasture (average ~ 245 mg kg-1) was significantly greater than that in the fertilizer-applied cropland (average 103 mg kg-1). The Po/phosphate ratio was also significantly greater in the manure-amended pasture (0.54) than in the fertilizer-applied cropland (0.42). Similarly, water quality data also showed that ditchwater near the pasture had a significantly greater flux of dissolved non-reactive P and a greater Po/phosphate ratio compared to the water near the fertilizer-applied sites. Furthermore, a greater Po/phosphate ratio in ditchwater was often observed during wet periods, and the ratio was positively correlated to the discharge (r = 0.42, p = 0.003). The study showed the agricultural management-specific Po accumulation and release and - Po/phosphate ratio that might affect the fate of P in agroecosystems.


Assuntos
Fósforo , Solo , Agricultura , Fertilizantes/análise , Esterco , Fosfatos , Fósforo/química , Solo/química
4.
Caries Res ; 55(5): 521-533, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34348278

RESUMO

There is a requirement to ensure that in vitro studies that use demineralized human dentine models are reliable and clinically relevant. The literature reports several strategies for these studies with a lack of consensus on the mode of action of the different demineralizing acids on human dentine. This in vitro study aims to characterize the effect of clinically relevant acids on human dentine, using standardized substrates and complementary analytical techniques. The study focuses on an analysis of the mineral content and the integrity of the collagen following partial demineralization. Samples of human dentine were exposed to a range of acids commonly encountered in the oral cavity. Characterization of the mineral content used Vickers micro-hardness, energy-dispersive spectroscopy, and X-ray fluorescence. Characterization of the collagen integrity was undertaken by means of scanning electron microscopy and hydroxyproline assay. The following conclusions were reached: (i) each demineralizing agent tested had a unique effect on the mineral levels; (ii) chelating agents, strong acids, and weak acids affect the mineral and organic phases of dentine in significantly different ways with no correlation between them; and (iii) the demineralizing agents caused some degree of collagen denaturation, citric acid causing the most damage. Overall, there is no clear link between the type of demineralizing agent and the effect on the organic and inorganic dentine. The choice of demineralizing agent should be aligned to the experiment objectives so that the selected dentine (caries or erosion) model is fit for the purpose.


Assuntos
Cárie Dentária , Dentina , Colágeno , Humanos , Hidroxiprolina , Microscopia Eletrônica de Varredura
5.
Sleep ; 41(9)2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860401

RESUMO

Study Objectives: Sleep is a reliable indicator of cognitive health in older individuals. Sleep spindles (SS) are non-rapid eye movement (NREM) sleep oscillations implicated in sleep-dependent learning. Their generation imply a complex activation of the thalamo-cortico-thalamic loop. Since SS require neuronal synchrony, the integrity of the white matter (WM) underlying these connections is of major importance. During aging, both SS and WM undergo important changes. The goal of this study was to investigate whether WM integrity could predict the age-related reductions in SS characteristics. Methods: Thirty young and 31 older participants underwent a night of polysomnographic recording and a 3T magnetic resonance imaging acquisition including a diffusion sequence. SS were detected in NREM sleep and EEG spectral analysis was performed for the sigma frequency band. WM diffusion metrics were computed in a voxelwise design of analysis. Results: Compared to young participants, older individuals showed lower SS density, amplitude, and sigma power. Diffusion metrics were correlated with SS amplitude and sigma power in tracts connecting the thalamus to the frontal cortex for the young but not for the older group, suggesting a moderation effect. Moderation analyses showed that diffusion metrics explained between 14% and 39% of SS amplitude and sigma power variance in the young participants only. Conclusion: Our results indicate that WM underlying the thalamo-cortico-thalamic loop predicts SS characteristics in young individuals, but does not explain age-related changes in SS. Other neurophysiological factors could better explain the effect of age on SS characteristics.


Assuntos
Envelhecimento/fisiologia , Fases do Sono/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Adulto , Fatores Etários , Idoso , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Polissonografia/métodos , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Adulto Jovem
6.
Phytochemistry ; 109: 84-95, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25468537

RESUMO

In addition to the already reported nukuhivensiums 1 and 2, 11 indole alkaloids were isolated from the bark of the plant Rauvolfia nukuhivensis, growing in the Marquesas archipelago. The known sandwicine (3), isosandwicine (4), spegatrine (8), lochneram (9), flavopereirine (13) have been found in this plant together with the norsandwicine (5), isonorsandwicine (6), Nb-methylisosandwicine (7), 10-methoxypanarine (10), nortueiaoine (11), tueiaoine (12). The structure elucidation was performed on the basis of a deep exploration of the NMR and HRESIMS data as well as comparison with literature data for similar compounds. Norsandwicine, 10-methoxypanarine, tueiaoine, and more importantly nukuhivensiums, were shown to significantly induce a reduction of IKr amplitude (HERG current). Molecular modelling through docking was performed in order to illustrate this result.


Assuntos
Alcaloides/química , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Indóis/química , Rauwolfia/química , Alcaloides/isolamento & purificação , Animais , Células CHO , Cricetulus , Células HEK293 , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Indóis/isolamento & purificação , Simulação de Acoplamento Molecular , Estrutura Molecular , Casca de Planta/química , Extratos Vegetais/química
7.
Haematologica ; 98(7): 1045-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23585526

RESUMO

Reports are emerging of hematologic responses associated with iron chelation therapy; however, studies are limited in aplastic anemia patients. Deferasirox reduced iron overload in aplastic anemia patients enrolled in the EPIC (Evaluation of Patients' Iron Chelation with Exjade(®)) study (n=116). A post hoc analysis of hematologic responses was conducted on 72 patients with evaluable hematologic parameters (according to UK guideline criteria), 24 of whom received deferasirox without concomitant immunosuppressive treatment. Partial hematologic responses were observed in 11 of 24 (45.8%) patients; all became transfusion-independent. One patient had an additional platelet response and one patient had an additional platelet and hemoglobin response. Mean serum ferritin levels at end of study were significantly reduced in partial hematologic responders (n=11; -3948 ± 4998 ng/mL; baseline 6693 ± 7014 ng/mL; percentage change from baseline -45.7%; P=0.0029). In non-responders, the reduction in serum ferritin was less pronounced (n=13; -2021 ± 3242 ng/mL; baseline 4365 ± 3063 ng/mL; % change from baseline -27.6%; P=0.0171). Alongside reduction in iron overload, deferasirox may, therefore, improve hematologic parameters in a subset of aplastic anemia patients. Further investigation is required to elucidate the mechanisms involved.


Assuntos
Anemia Aplástica/sangue , Anemia Aplástica/tratamento farmacológico , Benzoatos/uso terapêutico , Quelantes de Ferro/uso terapêutico , Triazóis/uso terapêutico , Adolescente , Adulto , Anemia Aplástica/patologia , Plaquetas/metabolismo , Plaquetas/patologia , Criança , Deferasirox , Feminino , Ferritinas/antagonistas & inibidores , Ferritinas/sangue , Hemoglobinas/metabolismo , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Neutrófilos/patologia , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
8.
Blood Transfus ; 11(1): 108-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22871821

RESUMO

BACKGROUND AND OBJECTIVES: Many patients with chronic anaemia require blood transfusions as part of their treatment regimen. As a result, iron overload will inevitably develop if not adequately managed by iron chelation therapy. There are many guidelines relating to transfusion and chelation practices for patients with transfusion-dependent anaemia; however, there is a lack of information on how treatment practices differ around the world. The objective of this manuscript is to highlight key features of current transfusion and chelation management, including similarities and differences across various anaemias and between geographical regions worldwide. MATERIALS AND METHODS: Data collected at study entry to the multicentre Evaluation of Patients' Iron Chelation with Exjade (EPIC) study, which recruited 1,744 patients with a variety of transfusion-dependent anaemias across 23 countries from three geographic regions, were assessed. These analyses compared transfusion and chelation treatment prior to the start of study treatment, together with iron burden assessed at study entry by serum ferritin, liver iron concentration and labile plasma iron levels. RESULTS AND CONCLUSIONS: Data show that transfusion and iron chelation practices differ between anaemias and between geographical regions; this may be linked to availability and accessibility of transfusion and chelation therapy, patients' compliance, physicians' attitudes, costs and use of treatment guidelines. Approximately 60% of these transfusion-dependent patients were severely iron overloaded with a serum ferritin level over 2,500 ng/mL, indicating that the risks of iron burden may have been underestimated and current iron chelation therapy, if considered, may not have been adequate to control iron burden.


Assuntos
Anemia , Fidelidade a Diretrizes , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro , Reação Transfusional , Adolescente , Adulto , Idoso , Anemia/sangue , Anemia/terapia , Criança , Pré-Escolar , Feminino , Ferritinas/sangue , Humanos , Ferro/sangue , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/prevenção & controle , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade
9.
Molecules ; 17(10): 12015-22, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23085652

RESUMO

The first phytochemical inspection of the Marquesan endemic plant Rauvolfia nukuhivensis led to the isolation and structure characterization of two new indolo[2,3-a]quinolizinium derivatives named nukuhivensium and N12-methyl-nukuhivensium. They feature an aromatic indolo[2,3-a]quinolizinium core, substituted at C-2 by a n-propyl group, which is unusual in this family of alkaloid derivatives. The structure elucidation was performed on the basis of NMR spectroscopy and especially by interpretation of 2D HMBC correlations. A biosynthetic pathway is proposed on the basis of known enzymatic transformations for this family of natural products. These compounds exhibited low antimicrobial activities.


Assuntos
Quinolizinas/química , Rauwolfia/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Quinolizinas/farmacologia
10.
Anemia ; 2012: 297641, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22924125

RESUMO

Treatment of iron overload using deferoxamine (DFO) is associated with significant deficits in patients' health-related quality of life (HRQOL) and low treatment satisfaction. The current article presents patient-reported HRQOL, satisfaction, adherence, and persistence data from ß-thalassemia (n = 274) and myelodysplastic syndrome (MDS) patients (n = 168) patients participating in the Evaluation of Patients' Iron Chelation with Exjade (EPIC) study (NCT00171821); a large-scale 1-year, phase IIIb study investigating the efficacy and safety of the once-daily oral iron chelator, deferasirox. HRQOL and satisfaction, adherence, and persistence to iron chelation therapy (ICT) data were collected at baseline and end of study using the Medical Outcomes Short-Form 36-item Health Survey (SF-36v2) and the Satisfaction with ICT Questionnaire (SICT). Compared to age-matched norms, ß-thalassemia and MDS patients reported lower SF-36 domain scores at baseline. Low levels of treatment satisfaction, adherence, and persistence were also observed. HRQOL improved following treatment with deferasirox, particularly among ß-thalassemia patients. Furthermore, patients reported high levels of satisfaction with deferasirox at end of study and greater ICT adherence, and persistence. Findings suggest deferasirox improves HRQOL, treatment satisfaction, adherence, and persistence with ICT in ß-thalassemia and MDS patients. Improving such outcomes is an important long-term goal for patients with iron overload.

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