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BACKGROUND & AIMS: Obeticholic acid (OCA) is the only licensed second-line therapy for primary biliary cholangitis (PBC). With novel therapeutics in advanced development, clinical tools are needed to tailor the treatment algorithm. We aimed to derive and externally validate the OCA response score (ORS) for predicting the response probability of individuals with PBC to OCA. METHODS: We used data from the Italian RECAPITULATE (N = 441) and the IBER-PBC (N = 244) OCA real-world prospective cohorts to derive/validate a score including widely available variables obtained either pre-treatment (ORS) or also after 6 months of treatment (ORS+). Multivariable Cox regressions with backward selection were applied to obtain parsimonious predictive models. The predicted outcomes were biochemical response according to POISE (alkaline phosphatase [ALP]/upper limit of normal [ULN]<1.67 with a reduction of at least 15%, and normal bilirubin), or ALP/ULN<1.67, or normal range criteria (NR: normal ALP, alanine aminotransferase [ALT], and bilirubin) up to 24 months. RESULTS: Depending on the response criteria, ORS included age, pruritus, cirrhosis, ALP/ULN, ALT/ULN, GGT/ULN, and bilirubin. ORS+ also included ALP/ULN and bilirubin after 6 months of OCA therapy. Internally validated c-statistics for ORS were 0.75, 0.78, and 0.72 for POISE, ALP/ULN<1.67, and NR response, which raised to 0.83, 0.88, and 0.81 with ORS+, respectively. The respective performances in validation were 0.70, 0.72, and 0.71 for ORS and 0.80, 0.84, and 0.78 for ORS+. Results were consistent across groups with mild/severe disease. CONCLUSIONS: We developed and externally validated a scoring system capable to predict OCA response according to different criteria. This tool will enhance a stratified second-line therapy model to streamline standard care and trial delivery in PBC.
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Endothelial dysfunction plays a key role in the development of liver cirrhosis. Among the biomarkers of endothelial dysfunction, the soluble form of Vascular Adhesion Protein-1 (sVAP-1) is an unconventional and less known adhesion molecule endowed also with amine oxidase activity. The aim of this study was to explore and correlate the behavior of sVAP-1 with that of the soluble vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) and with the severity of liver cirrhosis. A cross-sectional study was carried out by enrolling 28 controls, 59 cirrhotic patients without hepatocellular carcinoma, and 56 patients with hepatocellular carcinoma (HCC), mainly caused by alcohol abuse. The levels of adhesion molecules and of the pro-inflammatory cytokines (IL-6 and TNF-αα) were determined by immunoassay and the enzymatic activity of sVAP-1 by a fluorometric assay. In non-diabetic patients without HCC, a specific behavior of sVAP-1 was highlighted. Differently from sVCAM-1, sICAM-1, and cytokines, the sVAP-1 level was significantly increased only in the early stage of disease, and then, it decreased in the last stage (866 ± 390 ng/mL vs. 545 ± 316 ng/mL, in Child-Pugh class A vs. C, respectively, p < 0.05). Bivariate analysis correlates sVAP-1 to sVCAM-1, in the absence of HCC (Spearman's rho = 0.403, p < 0.01). Multiple linear regression analysis revealed that sVCAM-1 appears to be a predictor of sVAP-1 (ß coefficient = 0.374, p = 0.021). In conclusion, in non-diabetic and non-HCC cirrhotic patients, sVAP-1 may be a potential prognostic biomarker that, together with sVCAM-1 and pro-inflammatory cytokines, may provide information on the progression of sinusoidal liver endothelium damage.
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Amina Oxidase (contendo Cobre) , Biomarcadores , Carcinoma Hepatocelular , Cirrose Hepática , Molécula 1 de Adesão de Célula Vascular , Humanos , Masculino , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Feminino , Pessoa de Meia-Idade , Biomarcadores/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Prognóstico , Carcinoma Hepatocelular/sangue , Idoso , Amina Oxidase (contendo Cobre)/sangue , Neoplasias Hepáticas/sangue , Estudos Transversais , Molécula 1 de Adesão Intercelular/sangue , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Adulto , Fator de Necrose Tumoral alfa/sangue , Citocinas/sangue , Moléculas de Adesão CelularRESUMO
The ability of peculiar iron oxide nanoparticles (IONPs) to evade the immune system was investigated in vivo. The nanomaterial was provided directly into the farming water of zebrafish ( Danio rerio) and the distribution of IONPs and the delivery of oxytetracycline (OTC) was studied evidencing the successful overcoming of the intestinal barrier and the specific and prolonged (28 days) organotropic delivery of OTC to the fish ovary. Noteworthy, no sign of adverse effects was observed. In fish blood, IONPs were able to specifically bind apolipoprotein A1 (Apo A1) and molecular modeling showed the structural analogy between the IONP@Apo A1 nanoconjugate and high-density lipoprotein (HDL). Thus, the preservation of the biological identity of the protein suggests a plausible explanation of the observed overcoming of the intestinal barrier, of the great biocompatibity of the nanomaterial, and of the prolonged drug delivery (benefiting of the lipoprotein transport route). The present study promises novel and unexpected stealth materials in nanomedicine.
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Sistemas de Liberação de Medicamentos , Compostos Férricos/química , Nanopartículas Metálicas/química , Animais , Barreira Hematoencefálica , Cromatografia Líquida de Alta Pressão , Peixes , Espectrometria de Massas , Ligação ProteicaRESUMO
Polyamines (PAs) are involved in a variety of fundamental physio-pathologic processes. The concentration of these polycations in organs and tissues depends on their endogenous production and oxidation rates, and on their intake from foods. Besides being largely accepted as markers for the progress of several pathologies, PAs may exert themselves different effects on humans, ranging from being positive to be drastically detrimental depending on the organism conditions. Thus, if the determination of polyamines content in tissue samples is of great importance as they could be indicators of several diseases, their quantification in food is fundamental for modulating the diet to respond to a specific human health status. Thus, the determination of PA content in food is increasingly urgent. Standard analytical methods for polyamine quantification are mainly based on chromatography, where high-performance liquid chromatography and gas chromatography are the most often used, involving pre-column or post-column derivatization techniques. Driven by the growing need for rapid in situ analyses, electrochemical biosensors, comprising various combinations of different enzymes or nanomaterials for the selective bio-recognition and detection, are emerging as competitors of standard detection systems. The present review is aimed at providing an up-to-date overview on the recent progresses in the development of sensors and biosensors for the detection of polyamines in human tissues and food samples. Basic principles of different electrochemical (bio)sensor formats are reported and the applications in human tissues and in foods was evidenced.
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Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Análise de Alimentos , Poliaminas/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Humanos , Oxirredução , PolieletrólitosRESUMO
Custom immuno-magnetic devices are desirable tools for biomedical and biotechnological applications. Herein, surface active maghemite nanoparticles (SAMNs) are proposed as a versatile platform for developing tailored immuno-magnetic nano-carriers by simple wet reactions. Two examples for conjugating native and biotinylated antibodies were presented along with their successful applications in the recognition of specific foodborne pathogens. Nanoparticles were functionalized with rhodamine B isothiocyanate (RITC), leading to a fluorescent nano-conjugate, and used for binding anti-Campylobacter fetus antibodies (SAMN@RITC@Anti-Cf). The microorganism was selectively captured in the presence of two other Campylobacter species (C. jejuni and C. coli), as verified by PCR. Alternatively, SAMNs were modified with avidin, forming a biotin-specific magnetic nano-carrier and used for the immobilization of biotinylated anti-Listeria monocytogenes antibodies (SAMN@avidin@Anti-Lm). This immuno-magnetic carrier was integrated in piezoelectric quartz crystal microbalance (QCM) sensor for the detection of L. monocytogenes in milk, showing a detection limit of 3 bacterial cells. The present work presents a new category of customized immuno-magnetic nano-carriers as a competitive option for suiting specific applications. Graphical abstract á .
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Adjuvantes Imunológicos/química , Compostos Férricos/química , Magnetismo , Nanopartículas/química , Anticorpos Monoclonais/química , Avidina/química , Listeria/imunologia , Microscopia Eletrônica de Transmissão , Técnicas de Microbalança de Cristal de Quartzo/métodos , Propriedades de SuperfícieRESUMO
BACKGROUND: Mineral iron(III) recognition by bacteria is considered a matter of debate. The peculiar surface chemistry of novel naked magnetic nanoparticles, called SAMNs (surface active maghemite nanoparticles) characterized by solvent exposed Fe(3+) sites on their surface, was exploited for studying mineral iron sensing in Pseudomonas fluorescens. METHODS: SAMNs were applied for mimicking Fe(3+) ions in solution, acting as magnetically drivable probes to evaluate putative Fe(3+) recognition sites on the microorganism surface. Culture broths and nano-bio-conjugates were characterized by UV-Vis spectroscopy and mass spectrometry. RESULTS: The whole heritage of a membrane porin (OprF) of P. fluorescens Ps_22 cells was recognized and firmly bound by SAMNs. The binding of nanoparticles to OprF porin was correlated to a drastic inhibition of a siderophore (pyoverdine) biosynthesis and to the stimulation of the production and rate of formation of a secondary siderophore. The analysis of metabolic pathways, based on P. fluorescens Ps_22 genomic information, evidenced that this putative secondary siderophore does not belong to a selection of the most common siderophores. CONCLUSIONS: In the scenario of an adhesion mechanism, it is plausible to consider OprF as the biological component deputed to the mineral iron sensing in P. fluorescens Ps_22, as well as one key of siderophore regulation. GENERAL SIGNIFICANCE: The present work sheds light on mineral iron sensing in microorganisms. Peculiar colloidal naked iron oxide nanoparticles offer a useful approach for probing the adhesion of bacterial surface on mineral iron for the identification of the specific recognition site for this iron uptake regulation in microorganisms.
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Proteínas da Membrana Bacteriana Externa/genética , Nanopartículas de Magnetita/química , Porinas/genética , Tensoativos/química , Aderência Bacteriana/genética , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Compostos Férricos/química , Ferro/química , Minerais/química , Minerais/metabolismo , Porinas/química , Porinas/metabolismo , Pseudomonas fluorescens/química , Pseudomonas fluorescens/metabolismoRESUMO
BACKGROUND: Conversely to common coated iron oxide nanoparticles, novel naked surface active maghemite nanoparticles (SAMNs) can covalently bind DNA. Plasmid (pDNA) harboring the coding gene for GFP was directly chemisorbed onto SAMNs, leading to a novel DNA nanovector (SAMN@pDNA). The spontaneous internalization of SAMN@pDNA into cells was compared with an extensively studied fluorescent SAMN derivative (SAMN@RITC). Moreover, the transfection efficiency of SAMN@pDNA was evaluated and explained by computational model. METHODS: SAMN@pDNA was prepared and characterized by spectroscopic and computational methods, and molecular dynamic simulation. The size and hydrodynamic properties of SAMN@pDNA and SAMN@RITC were studied by electron transmission microscopy, light scattering and zeta-potential. The two nanomaterials were tested by confocal scanning microscopy on equine peripheral blood-derived mesenchymal stem cells (ePB-MSCs) and GFP expression by SAMN@pDNA was determined. RESULTS: Nanomaterials characterized by similar hydrodynamic properties were successfully internalized and stored into mesenchymal stem cells. Transfection by SAMN@pDNA occurred and GFP expression was higher than lipofectamine procedure, even in the absence of an external magnetic field. A computational model clarified that transfection efficiency can be ascribed to DNA availability inside cells. CONCLUSIONS: Direct covalent binding of DNA on naked magnetic nanoparticles led to an extremely robust gene delivery tool. Hydrodynamic and chemical-physical properties of SAMN@pDNA were responsible of the successful uptake by cells and of the efficiency of GFP gene transfection. GENERAL SIGNIFICANCE: SAMNs are characterized by colloidal stability, excellent cell uptake, persistence in the host cells, low toxicity and are proposed as novel intelligent DNA nanovectors for efficient cell transfection.
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DNA/química , Técnicas de Transferência de Genes , Nanopartículas/química , Transfecção/métodos , Fenômenos Biofísicos , Coloides/química , DNA/genética , Compostos Férricos/química , Vetores Genéticos , Humanos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Tamanho da Partícula , Plasmídeos/química , Plasmídeos/genéticaRESUMO
The present study is aimed at the exploration of achievable improvements for Cr(VI) ex situ and in situ water remediation by using novel naked colloidal maghemite (γ-Fe2 O3 ) nanoparticles (surface active maghemite nanoparticles, SAMNs). The reliability of SAMNs for Cr(VI) binding and removal was demonstrated, and SAMN@Cr(VI) complex was characterized, as well as the covalent nature of the absorption was unequivocally proved. SAMNs were structurally and magnetically well conserved after Cr(VI) binding. Thus, in consideration of their affinity for Cr(VI) , SAMNs were exploited in a biological model system, mimicking a real in situ application. The assay evidenced a progressive reduction of revertant colonies of Salmonella typhimurium TA100 strain, as maghemite nanoparticles concentration increased, till the complete suppression of Cr(VI) mutagen effect. Finally, an automatic modular pilot system for continuous magnetic removal and recovery of Cr(VI) from water is proposed. SAMNs, thanks to their colloidal, binding, and catalytic properties, represent a promising tool as a reliable nanomaterial for water remediation by Cr(VI) .
RESUMO
Dichromate binds to surface-active maghemite nanoparticles (SAMNs) to form a stable core-shell nanostructures (SAMN@Cr(VI) ). The hybrid was characterized by Mössbauer spectroscopy, high-angle annular dark-field imaging, electron energy-loss spectroscopy, and electrochemical techniques, which revealed a strong interaction of dichromate with the nanoparticle surface. Electrochemical characterization showed lower charge-transfer resistance, better electrochemical performance, and more reversible electrochemical behavior with respect to naked SAMNs. Moreover, SAMN@Cr(VI) is an excellent electrocatalyst for hydrogen peroxide reduction. Furthermore, an enzyme, namely, bovine serum amine oxidase (BSAO: ECâ 1.4.3.6), was immobilized on SAMN@Cr(VI) by self-assembly to give a ternary hybrid nanostructured catalyst for polyamine oxidation (SAMN@Cr(VI) -BSAO). SAMN@Cr(VI) -BSAO was applied for the development of a reagentless, fast, inexpensive, and interference-free polyamine biosensor, which was successfully exploited for the discrimination of tumorous tissue from healthy tissue in human crude liver extracts.
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Compostos Férricos/química , Neoplasias Hepáticas/diagnóstico , Nanopartículas/química , Neoplasias/diagnóstico , Poliaminas/análise , Animais , Técnicas Biossensoriais/métodos , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/diagnóstico , Bovinos , Técnicas Eletroquímicas , Enzimas Imobilizadas , Humanos , Neoplasias Hepáticas/química , Fenômenos Magnéticos , Nanomedicina , Neoplasias/química , Oxirredução , Oxirredutases/química , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
A novel core-shell hybrid nanomaterial composed of peculiar maghemite nanoparticles (surface-active maghemite nanoparticles (SAMNs)) as the core and tannic acid (TA) as the shell was developed by self-assembly of ferric tannates onto the surface of SAMNs by simple incubation in water. The hybrid nanomaterial (SAMN@TA) was characterized by using UV/Vis, FTIR, and Mössbauer spectroscopies, magnetization measurements, and X-ray powder diffraction, which provide evidence of a drastic reorganization of the iron oxide surface upon reaction with TA and the formation of an outer shell that consists of a cross-linked network of ferric tannates. According to a Langmuir isotherm analysis, SAMN@TA offers one of most stable iron complexes of TA reported in the literature to date. Moreover, SAMN@TA was characterized by using electrical impedance spectroscopy, voltammetry, and chronoamperometry. The nanostructured ferric tannate interface showed improved conductivity and selective electrocatalytic activity toward the oxidation of polyphenols. Finally, a carbon-paste electrode modified with SAMN@TA was used for the determination of polyphenols in blueberry extracts by square-wave voltammetry.
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Técnicas Eletroquímicas , Compostos Férricos/química , Nanoestruturas/química , Polifenóis/análise , Taninos/química , CatáliseRESUMO
Advantage has been taken of the relative promiscuity of commonly used inhibitors of protein kinase CK2 to develop compounds that can be exploited for the selective inhibition of druggable kinases other than CK2 itself. Here we summarize data obtained by altering the scaffold of CK2 inhibitors to give rise to novel selective inhibitors of DYRK1A and to a powerful cell permeable dual inhibitor of PIM1 and CK2. In the former case one of the new compounds, C624 (naphto [1,2-b]benzofuran-5,9-diol) displays a potency comparable to that of the first-in-class DYRK1A inhibitor, harmine, lacking however the drawback of drastically inhibiting monoamine oxidase-A (MAO-A) as harmine does. On the other hand the promiscuous CK2 inhibitor 4,5,6,7-tetrabromo-1H-benzimidazole (TBI,TBBz) has been derivatized with a sugar moiety to generate a 1-(ß-D-2'-deoxyribofuranosyl)-4,5,6,7-tetrabromo-1H-benzimidazole (TDB) compound which inhibits PIM1 and CK2 with comparably high efficacy (IC50 values<100nM) and remarkable selectivity. TDB, unlike other dual PIM1/CK2 inhibitors described in the literature is readily cell permeable and displays a cytotoxic effect on cancer cells consistent with concomitant inhibition of both its onco-kinase targets. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012).
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Caseína Quinase II/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Adipócitos/enzimologia , Benzimidazóis/química , Benzimidazóis/metabolismo , Benzimidazóis/farmacologia , Sítios de Ligação , Caseína Quinase II/química , Caseína Quinase II/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Harmina/química , Harmina/farmacologia , Humanos , Cinética , Modelos Moleculares , Estrutura Molecular , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/farmacologia , Fosforilação/efeitos dos fármacos , Ligação Proteica , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/química , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Quinases DyrkRESUMO
Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by inflammation and fibrosis of intra- and/or extrahepatic bile ducts leading to the formation of multifocal strictures alternated to bile duct dilatations. The diagnosis of the most common subtype of the disease, the large duct PSC, is based on the presence of elevation of cholestatic indices, the association of typical cholangiographic findings assessed by magnetic resonance cholangiography and the exclusion of causes of secondary sclerosing cholangitis. Liver biopsy is not routinely applied for the diagnosis of large duct PSC but is mandatory in the case of suspicion of small duct PSC or overlap with autoimmune hepatitis.
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Colangite Esclerosante , Humanos , Colangite Esclerosante/complicações , Colangite Esclerosante/diagnóstico por imagem , InflamaçãoRESUMO
An important tool to explore personal experience of symptoms, treatment and clinical outcome is stratification of illness perception in patients affected by PBC. AIM: To assess the perception of illness in a cohort of Italian patients with PBC. METHODS: Between June and December 2019, a specific questionnaire was administered to a pool of 210 patients from 7 tertiary Italian centers, in order to identify and assess the patient's past history, symptoms and their impact on the quality of life, follow-up, treatment and perceived satisfaction of patients toward the provided care. RESULTS: Fatigue, pruritus, and abdominal discomfort and sicca syndrome were present in 50.4%, 45%, 30.4% and 28.5% of patients, fatigue having the most impacting the daily-life. After a consultation with a specialist, the diagnosis of PBC was met within 18 months for 143 patients. Patients were mostly concerned about possible health problems that occur and in 25% of cases, symptoms had a negative impact on their life. Eighty percent of patients said they were satisfied with efficacy and tolerability of treatment, while 26% requested an improvement in the relationship with the specialist. CONCLUSIONS: The results highlight the importance of both promoting timely referral to the specialist and facilitating communication between healthcare professionals and patients.
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Colangite , Cirrose Hepática Biliar , Fadiga , Humanos , Motivação , Percepção , Qualidade de VidaRESUMO
Aedes aegypti mosquitos are widespread vectors of several diseases and their control is of primary importance for biological and environmental reasons, and novel safe insecticides are highly desirable. An eco-friendly photosensitizing magnetic nanocarrier with larvicidal effects on Aedes aegypti was proposed. The innovative core-shell hybrid nanomaterial was synthesized by combining peculiar magnetic nanoparticles (called Surface Active Maghemite Nanoparticles - SAMNs, the core) and chlorin-e6 as photosensitizer (constituting the shell) via self-assembly in water. The hybrid nanomaterial (SAMN@chlorin) was extensively characterized and tested for the photocidal activity on larvae of Aedes aegypti. The SAMN@chlorin core-shell nanohybrid did not present any toxic effect in the dark, but, upon light exposure, showed a higher photocidal activity than free chlorin-e6. Moreover, the eco-toxicity of SAMN@chlorin was determined in adults and neonates of Daphnia magna, where delayed toxicity was observed only after prolonged (≥4â¯h) exposure to intense light, on the green alga Pseudokirchneriella subcapitata and on the duckweed Lemna minor on which no adverse effects were observed. The high colloidal stability, the physico-chemical robustness and the magnetic drivability of the core-shell SAMN@chlorin nanohybrid, accompanied by the high photocidal activity on Aedes aegypti larvae and reduced environmental concerns, can be proposed as a safe alternative to conventional insecticides.
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Aedes , Compostos Férricos/química , Inseticidas/química , Larva , Nanopartículas/química , Porfirinas/química , Animais , Clorofíceas/efeitos dos fármacos , Clorofíceas/efeitos da radiação , Daphnia/efeitos dos fármacos , Daphnia/efeitos da radiação , Inseticidas/toxicidade , Luz , Porfirinas/toxicidade , Propriedades de Superfície , Água/químicaRESUMO
Iron oxide nanomaterials are considered promising tools for improved therapeutic efficacy and diagnostic applications in biomedicine. Accordingly, engineered iron oxide nanomaterials are increasingly proposed in biomedicine, and the interdisciplinary researches involving physics, chemistry, biology (nanotechnology) and medicine have led to exciting developments in the last decades. The progresses of the development of magnetic nanoparticles with tailored physico-chemical and surface properties produced a variety of clinically relevant applications, spanning from magnetic resonance imaging (MRI), drug delivery, magnetic hyperthermia, to in vitro diagnostics. Notwithstanding the wellknown conventional synthetic procedures and their wide use, along with recent advances in the synthetic methods open the door to new generations of naked iron oxide nanoparticles possessing peculiar surface chemistries, suitable for other competitive biomedical applications. New abilities to rationally manipulate iron oxides and their physical, chemical, and biological properties, allow the emersion of additional possibilities for designing novel nanomaterials for theranostic applications.
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Compostos Férricos/farmacologia , Nanopartículas Metálicas/química , Compostos Férricos/química , Humanos , MagnetismoRESUMO
An innovative core-shell nanocarrier, combining the magnetism of surface active maghemite nanoparticles (SAMNs, the core) and tannic acid (TA, the shell) was self-assembled by simple incubation in water. Due to the drastic reorganization of SAMN surface, the prepared magnetic nanocarrier (SAMN@TA) resulted as one of the most robust nanomaterial bearing TA to date. Nevertheless, the ferric tannates network, constituting the SAMN@TA shell, and the free tannic acid display comparable chemical behavior. The antimicrobial properties of SAMN@TA were tested on Listeria monocytogenes in comparison with free TA, showing similar bacteriostatic effects at relatively low concentrations. Besides the preservation of the TA inhibitory activity toward L. monocytogenes, the possibility of being magnetically removed leaving no residues into the matrix makes this nanocarrier an innovative processing aid for surface treatments. Thus, SAMN@TA can be used as an effective, low-cost and environmentally friendly antimicrobial nanomaterial for the food industry applications.
Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Nanopartículas/química , Antibacterianos/farmacologia , Compostos Férricos/química , Indústria Alimentícia , Magnetismo , Taninos/químicaRESUMO
Citrinin is a nephrotoxic mycotoxin which can be synthesized by Monascus mold during the fermentation process in foods. Monascus, generally described as red mold, is a red-pigmented filamentous fungus attracting a great interest for the production of natural dyes and cholesterol-lowering statins. We individuated a specie of Monascus producing high amount of natural dyes. However, this high pigmentation was correlated with the production of citrinin. Peculiar magnetic nanoparticles, synthesized in-house and called "Surface Active Maghemite Nanoparticles" (SAMNs), are proposed as an efficient and reliable mean for citrinin removal from Monascus treated foods. The nanomaterial efficiency for citrinin binding was proved on Monascus suspensions, and SAMN@citrinin complex was characterized by MÓ§ssbauer spectroscopy and magnetization measurements, showing that SAMNs resulted structurally and magnetically well conserved after citrinin binding. SAMNs are excellent and stable magnetic nano-carrier for toxin removal, which can be applied in food industry.
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Citrinina/análise , Indústria Alimentícia/métodos , Nanopartículas de Magnetita/química , Monascus/metabolismo , Fermentação , Corantes de Alimentos/metabolismo , Contaminação de Alimentos/prevenção & controle , Microscopia Eletrônica de Transmissão , Monascus/crescimento & desenvolvimento , Espectroscopia de Mossbauer , Propriedades de SuperfícieRESUMO
Proteome modifications in a biological fluid can potentially indicate the occurrence of pathologies, even if the identification of a proteome fingerprint correlated to a specific disease represents a very difficult task. When a nanomaterial is introduced into a biological fluid, macromolecules compete to form a protein corona on the nanoparticle surface, and depending on the specific proteome, different patterns of proteins will form the final protein corona shell depending on their affinity for the nanoparticle surface. Novel surface active maghemite nanoparticles (SAMNs) display a remarkable selectivity toward protein corona formation, and they are able to concentrate proteins and peptides presenting high affinities for their surface even if they are present in very low amounts. Thus, SAMNs may confer visibility to hidden biomarkers correlated to the occurrence of a pathology. In the present report, SAMNs were introduced into milk samples from healthy cows and from animals affected by mastitis, and the selectively bound protein corona shell was easily analyzed and quantified by gel electrophoresis and characterized by mass spectrometry. Upon incubation in mastitic milk, SAMNs were able to selectively bind αs2-casein fragments containing the FALPQYLK sequence, as part of the larger casocidin-1 peptide with strong antibacterial activity, which were not present in healthy samples. Thus, SAMNs can be used as a future candidate for the rapid diagnosis of mastitis in bovine milk. The present report proposes protein competition for SAMN protein corona formation as a means of mirroring proteome modifications. Thus, the selected protein shell on the nanoparticles results in a fingerprint of the specific pathology.
Assuntos
Biomarcadores/metabolismo , Mastite/metabolismo , Coroa de Proteína/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Sequência de Aminoácidos , Animais , Biomarcadores/química , Caseínas/química , Caseínas/metabolismo , Bovinos , Feminino , Compostos Férricos/química , Espectrometria de Massas/métodos , Mastite/diagnóstico , Nanopartículas Metálicas/química , Leite/química , Leite/metabolismo , Proteínas do Leite/química , Proteínas do Leite/metabolismo , Coroa de Proteína/química , Proteoma/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Propriedades de SuperfícieRESUMO
The biological effect of alkaline water consumption is object of controversy. The present paper presents a 3-year survival study on a population of 150 mice, and the data were analyzed with accelerated failure time (AFT) model. Starting from the second year of life, nonparametric survival plots suggest that mice watered with alkaline water showed a better survival than control mice. Interestingly, statistical analysis revealed that alkaline water provides higher longevity in terms of "deceleration aging factor" as it increases the survival functions when compared with control group; namely, animals belonging to the population treated with alkaline water resulted in a longer lifespan. Histological examination of mice kidneys, intestine, heart, liver, and brain revealed that no significant differences emerged among the three groups indicating that no specific pathology resulted correlated with the consumption of alkaline water. These results provide an informative and quantitative summary of survival data as a function of watering with alkaline water of long-lived mouse models.
RESUMO
Recently, the indiscriminate use of antibiotics in the aquaculture sector has raised public concern because of possible toxic effects, development of bacterial resistance, and accumulation of residues in individual tissues. Even if several countries have developed regulations about their use, it is clear that long-term growth of the aquaculture industry requires both ecologically sound practices and sustainable resource management. Alternative strategies for better management of antibiotic administration are of primary interest to improve absorption rates and, as a consequence, to reduce their release into the aquatic environment. The present study investigates, for the first time to our knowledge, a new methodology for oxytetracycline (OTC) administration through the use of iron oxide nanoparticles (NPs) (made of maghemite γ-Fe2O3) in zebrafish (Danio rerio). Fish were divided into 4 experimental groups: control; group A exposed to 4 mg/L OTC (through water); group B exposed to the 100 mg/L SAMNs@OTC complex (equivalent to 4 mg/L OTC), and group C exposed to bare NPs. No detoxification processes or anatomical alterations were observed in fish exposed to bare NPs. Exposure of fish to the SAMNs@OTC complex resulted in a 10 times higher OTC accumulation with respect to using water exposure. This new OTC administration method seems much more efficient with respect to the traditional way of exposure and has the potentiality to reduce antibiotic utilization and possible environmental impacts. However, the dynamics related to OTC release from the SAMNs@OTC complex are still not clear and need further investigations.