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1.
Colloids Surf B Biointerfaces ; 241: 114043, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38901266

RESUMO

Responsiveness of liposomes to external stimuli, such as light, should allow a precise spatial and temporal control of release of therapeutic agents or ion transmembrane transport. Here, some aryl-azo derivatives of thymol are synthesized and embedded into liposomes from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine to obtain light-sensitive membranes whose photo-responsiveness, release behaviour, and permeability towards Cl- ions are investigated. The hybrid systems are in-depth characterized by dynamic light scattering, atomic force microscopy and Raman spectroscopy. In liposomal bilayer the selected guests undergo reversible photoinduced isomerization upon irradiation with UV and visible light, alternately. Non-irradiated hybrid liposomes retain entrapped 5(6)-carboxyfluorescein (CF), slowing its spontaneous leakage, whereas UV-irradiation promotes CF release, due to guest trans-to-cis isomerization. Photoisomerization also influences membrane permeability towards Cl- ions. Data processing, according to first-order kinetics, demonstrates that Cl- transmembrane transport is enhanced by switching the guest from trans to cis but restored by back-switching the guest from cis to trans upon illumination with blue light. Finally, the passage of Cl- ions across the bilayer can be fine-tuned by irradiation with light of longer λ and different light-exposure times. Fine-tuning the photo-induced structural response of the liposomal membrane upon isomerization is a promising step towards effective photo-dynamic therapy.

2.
Healthcare (Basel) ; 11(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36767022

RESUMO

This systematic study aims at analyzing the differences between the approach of the European healthcare systems to the pharmaceutical market and the American one. This paper highlights the opportunities and the limitations given by the application of managed entry agreements (MEAs) in European countries as opposed to the American market, which does not regulate pharmaceutical prices. Data were collected from the Organisation for Economic Co-operation and Development (OECD), the European Medicines Agency, and the national healthcare agencies of US and European countries. A literature review was undertaken in PubMed, Scopus, MEDLINE, and Google for a period ten years (2010-2019). The period 2020-2021 was considered to compare health expenditure before and after the SARS-CoV-2 pandemic. Scarce information from national agencies has been given in terms of MEAs related to the COVID-19 pandemic. The comparison between the United States approach and the European one shows the importance of a market access regulation to reduce the cost of therapies, increasing the efficiency of national healthcare systems and the advantages in terms of quality and accessibility to the final users: patients. Nevertheless, it seems that the golden age of MEAs for Europe was during the examined period. Except for Italy, countries will move to other forms of reimbursements to obtain higher benefits, reducing the costs of an inefficient implementation and outcomes in the medium term.

3.
Front Cardiovasc Med ; 9: 1067501, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36568549
4.
Pharmaceutics ; 14(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36145568

RESUMO

The encapsulation of peptides and proteins in nanosystems has been extensively investigated for masking unfavorable biopharmaceutical properties, including short half-life and poor permeation through biological membranes. Therefore, the aim of this work was to encapsulate a small antimicrobial hydrophilic peptide (H-Ser-Pro-Trp-Thr-NH2, FS10) in PEG-PLGA (polyethylene glycol-poly lactic acid-co-glycolic acid) nanoparticles (Nps) and thereby overcome the common limitations of hydrophilic drugs, which because they facilitate water absorption suffer from rapid degradation. FS10 is structurally related to the well-known RNAIII inhibiting peptide (RIP) and inhibits S. aureus biofilm formation. Various parameters, including different method (double emulsion and nanoprecipitation), pH of the aqueous phase and polymeric composition, were investigated to load FS10 into PEG-PLGA nanoparticles. The combination of different strategies resulted in an encapsulation efficiency of around 25% for both the double emulsion and the nanoprecipitation method. It was found that the most influential parameters were the pH­which tailors the peptides charge­and the polymeric composition. FS10-PEG-PLGA nanoparticles, obtained under optimized parameters, showed size lower than 180 nm with zeta potential values ranging from −11 to −21 mV. In vitro release studies showed that the Nps had an initial burst release of 48−63%, followed by a continuous drug release up to 21 h, probably caused by the porous character of the Nps. Furthermore, transmission electron microscopy (TEM) analysis revealed particles with a spherical morphology and size of around 100 nm. Antimicrobial assay showed that the minimum inhibitory concentration (MIC) of the FS10-loaded Nps, against S. aureus strains, was lower (>128 µg/mL) than that of the free FS10 (>256 µg/mL). The main goal of this work was to develop polymeric drug delivery systems aiming at protecting the peptide from a fast degradation, thus improving its accumulation in the target site and increasing the drug-bacterial membrane interactions.

7.
RSC Med Chem ; 12(11): 1944-1949, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34825189

RESUMO

Novel boron-based compounds (BBCs) were synthesized and evaluated as potential candidates for the development of novel drugs against Alzheimer's disease (AD). The neuroprotective profile of novel BBCs was evaluated using Aß1-42-treated-SH-SY5Y cells while their antioxidant activity was evaluated by total antioxidant capacity (TAC) and total oxidative status (TOS) assays. Results showed that BLA (a novel boron-based hybrid containing an antioxidant portion) inhibited cell death induced by Aß1-42-exposure in differentiated SH-SY5Y cells, resulting in an increase in cell viability by 25-33% (MTT assay) and by 63-71% (LDH assay) in a concentration range of 25-100 µM. Antioxidant assays demonstrated a good capability of BLA to counteract the oxidative status. Moreover, BLA possessed a significant ability to inhibit acetylcholinesterase (AChE) (22.96% at 50 µM), an enzyme whose enzymatic activity is increased in AD patients. In the present work, absorption and distribution properties of boron-based hybrids were predicted using Pre-ADMET software. In vitro preliminary results suggested that boron-based hybrids could be new structural scaffolds for the development of novel drugs for the management of AD.

9.
Front Med (Lausanne) ; 8: 510421, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222267

RESUMO

Medical practice is increasingly coming under the guidance of statistical-mathematical models that are, undoubtedly, valuable tools but are also only a partial representation of reality. Indeed, given that statistics may be more or less adequate, a model is still a subjective interpretation of the researcher and is also influenced by the historical context in which it operates. From this opinion, I will provide a short historical excursus that retraces the advent of probabilistic medicine as a long process that has a beginning that should be sought in the discovery of the complexity of disease. By supporting the belonging of this evolution to the scientific domain it is also acknowledged that the underlying model can be imperfect or fallible and, therefore, confutable as any product of science. Indeed, it seems non-trivial here to recover these concepts, especially today where clinical decisions are entrusted to practical guidelines, which are a hybrid product resulting from the aggregation of multiple perspectives, including the probabilistic approach, to disease. Finally, before the advent of precision medicine, by limiting the use of guidelines to the original consultative context, an aged approach is supported, namely, a relationship with the individual patient.

10.
Medicine (Baltimore) ; 100(25): e26369, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34160409

RESUMO

BACKGROUND: Diseases of the oral cavity (OC) with an infectious trigger such as caries and periodontal disease are extremely common in the general population and can also have effects at the cardiovascular level. The oral salivary flow, with its buffering capacity, is able to regulate the pH of the OC and, therefore, significantly contribute to the ecological balance of the microenvironment in which the oral microbiome (OM) develops. On the other side, when the quality/quantity of salivary flow is altered it is supposed the disruption of this balance with the potential increase in oral pathogens and triggered diseases. Among the endogenous substances able to exert a significant effect on the salivary flow and its characteristics, carnosine (Car), a dipeptide originally isolated in skeletal muscle, represents, thanks to the known buffering properties, a promising principle. METHODS: We aimed this protocol to evaluate the quantitative/qualitative characteristics of the salivary flow in healthy volunteer subjects (n = 20) and in subjects suffering from common OC pathologies (n = 40), before and after 7 days of supplementation with SaliflussTM (Metis Healthcare srl, Milan, Italy), a Class I medical device on the market as 400 mg mucoadhesive oral tablets that has Car as the main ingredient. DISCUSSION: Combining the characteristics of saliva with the OM and comparing them with OC pathologies, we expect to clarify their reciprocal relationship and, using quantitative proteomics techniques, to help clarify the mechanism of action of Car.


Assuntos
Carnosina/administração & dosagem , Cárie Dentária/dietoterapia , Gengivite/dietoterapia , Periodontite/dietoterapia , Saliva/química , Administração Bucal , Adolescente , Adulto , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Cárie Dentária/complicações , Cárie Dentária/prevenção & controle , Suplementos Nutricionais , Gengivite/microbiologia , Gengivite/prevenção & controle , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Masculino , Microbiota/fisiologia , Mucosa Bucal/microbiologia , Periodontite/microbiologia , Periodontite/prevenção & controle , Saliva/metabolismo , Comprimidos , Adulto Jovem
11.
Biochim Biophys Acta Biomembr ; 1863(10): 183667, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111414

RESUMO

An amphiphilic calix[6]arene, alone or complexed with an axle to form a pseudo-rotaxane, has been embedded into liposomes prepared from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and the permeability of the membrane-doped liposomes towards Cl- ions has been evaluated by using lucigenin as the fluorescent probe. The pseudo-rotaxane promotes transmembrane transport of Cl- ions more than calix[6]arene does. Surprisingly, the quenching of lucigenin was very fast for liposomes doped with the positively charged axle alone. Molecular dynamics (MD) simulations and quantum-chemical calculations were also carried out for providing a semi-quantitative support to the experimental results.


Assuntos
Calixarenos/metabolismo , Cloretos/metabolismo , Ionóforos/metabolismo , Bicamadas Lipídicas , Lipossomos , Biologia Computacional/métodos , Simulação de Dinâmica Molecular , Relação Estrutura-Atividade
12.
Z Naturforsch C J Biosci ; 76(7-8): 329-335, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32889798

RESUMO

Several epidemiologic, clinical and experimental reports indicate that nonsteroidal anti-inflammatory drugs (NSAIDs) could have a potential as anticancer agents. The aim of this study was the evaluation of cytotoxic potential in human glioblastoma cells of novel synthesized NSAID derivatives, obtained by linking, through a spacer, α-lipoic acid (ALA) to anti-inflammatory drugs, such as naproxen (AL-3, 11 and 17), flurbiprofen (AL-6, 13 and 19) and ibuprofen (AL-9, 15 and 21). The effects on the level of gene expression were also determined using quantitative real-time polymerase chain reaction (qRT-PCR) analysis. According to our results, NSAID derivatives exhibited concentration dependent cytotoxic effects on U87-MG cell line when compared with the control group. Moreover, treatment of the most active compounds (AL-3, AL-6 and AL-9) caused upregulation of tumor suppressor gene PTEN and downregulation of some oncogenes such as AKT1, RAF1 and EGFR. In conclusion, our results revealed that AL-3, AL-6 and AL-9 could be suitable candidates for further investigation to develop new pharmacological strategies for the prevention of cancer.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Anti-Inflamatórios não Esteroides/química , Antineoplásicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Relação Dose-Resposta a Droga , Receptores ErbB/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Estrutura Molecular , Subunidade p50 de NF-kappa B/genética , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Acta Biomed ; 91(2): 234-235, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32420956

RESUMO

In western democracies, individual behaviour will be crucial to control the spread of COVID-19, as well as government actions [1] that unfortunately, except China, South Korea and Italy, followed by others,  seems to be generally unconvinced and, speculatively, late. Indeed human history has been marked by epidemics/pandemics which have affected, more or less, large geographical areas [2]. Italy, as well as the rest of Europe, has often been affected by these phenomena and, Lombardy, due to his position, was, as today by COVID-19, severely stroked in Italy that is, after China, the second most affected country [3]. This is also linked to the position of Lombardy and its capital, Milan, but this is beyond this brief comment. There are several differences between the past plagues and the actual COVID-19 pandemic and these must be sought in the increased ability to transmit diseases at-distance through the mobility of humans and goods [4], and in the catastrophic consequences of the breakdown of ecosystems, as told, a few years ago, by David Quammen in the book Spillover [5].


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Peste/história , Pneumonia Viral/epidemiologia , COVID-19 , História do Século XVII , Itália/epidemiologia , Pandemias , Peste/epidemiologia , SARS-CoV-2
19.
J Pharm Biomed Anal ; 184: 113205, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32113116

RESUMO

Plants belonging to Artemisia spp. are known to biosynthesize a wide panel of 3,3-dimethylallyl- and sesquiterpenyl- substituted coumarins. In this short communication we applied a novel extraction methodology based on the use of subcritical butane under a counter-current mode to further characterize the presence of selected biologically active oxyprenylated phenylpropanoids, namely coumarins and ferulic acid derivatives, in extracts deriving from aerial parts of Artemisia vulgaris L. (commonly known as "common mugwort") (Asteraceae). In the mean time, we assessed the efficiency of the above mentioned extractive methodology with other routes like maceration and ultrasounds and microwaves-based methods using absolute EtOH as the solvents. UHPLC analysis coupled to UV/Vis detection revealed that, among the 5 pure chemical standard assayed, only umbelliprenin (7-farnesyloxycoumarin) was recorded, while boropinic acid, 4'-geranyloxyferulic acid, 7-isopentenyloxycoumarin, and auraptene were not detected. The best extractive yield (0.18 %) was obtained after extaction with subcritical butane. The presence of umbelliprenin in Artemisia plant species has been reported herein for the first time. This coumarin may represent the biosynthetic precursors of sesquiterpenyloxycoumarins with more complex structures typically found in this genus.


Assuntos
Artemisia/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/química , Extratos Vegetais/química , Umbeliferonas/química , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Cumáricos/química , Cumarínicos/química
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