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1.
J Liposome Res ; 32(1): 83-91, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34839768

RESUMO

The aim of the present study is the development and evaluation of the physicochemical properties of chimeric hydrogenated soya phosphatidylcholine (HSPC) and egg phosphatidylcholine (EggPC) liposomes with incorporated triblock copolymer Poloxamer P407 (P407). The physicochemical assay was held in water HPLC-grade and Foetal Bovine Serum (FBS), in order to determine whether these systems can be used as drug or antigen delivery nanosystems. Dynamic and electrophoretic light scattering (DLS/ELS) techniques were used for the measurement of the hydrodynamic diameter, the polydispersity index, and the ζ-potential of the prepared nanosystems. The incorporation of the P407 resulted in a size reduction of all systems. A decrease in the hydrodynamic diameter and polydispersity index were also found as a result of increasing the storage temperature from 4 °C to 25 °C, attributed to P407. The experiments that were carried out in FBS, showed that the addition of P407 improved systems stealth properties. Concluding, we propose P407 as a promising alternative to PEG in the development of lipid nanoparticles with optimized bio- and shelf-stability.


Assuntos
Lipossomos , Nanopartículas , Materiais Biocompatíveis , Lipossomos/química , Nanopartículas/química , Poloxâmero/química
2.
Pharmaceutics ; 16(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38543244

RESUMO

Neurodegenerative diseases, such as Alzheimer's and Parkinson's, affect a wide variety of the population and pose significant challenges with progressive and irreversible neural cell loss. The limitations of brain-targeting therapies and the unclear molecular mechanisms driving neurodegeneration hamper the possibility of developing successful treatment options. Thus, nanoscale drug delivery platforms offer a promising solution. This paper explores and compares lipidic nanoparticles, extracellular vesicles (EVs), and hybrid liposomal-EV nanoplatforms as advanced approaches for targeted delivery to combat neurodegeneration. Lipidic nanoparticles are well-characterized platforms that allow multi-drug loading and scalable production. Conversely, EVs offer the ability of selectively targeting specific tissues and high biocompatibility. The combination of these two platforms in one could lead to promising results in the treatment of neurodegeneration. However, many issues, such as the regulatory framework, remain to be solved before these novel products are translated into clinical practice.

3.
Int J Pharm ; 651: 123788, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38185341

RESUMO

Exosomes are naturally derived information carriers that present interest as drug delivery systems. However, their vague cargo and isolation difficulties hinder their use in clinical practice. To overcome these limitations, we developed exosome-like nanoparticles, consisted of the main lipids of exosomes, using two distinct methods: thin-film hydration and 3D-printed microfluidics. Our novel microfluidic device, fabricated through digital light processing printing, demonstrated a favorable architecture to produce exosome-like nanoparticles. We compared these two techniques by analyzing the physicochemical characteristics (size, size distribution, and ζ-potential) of both unloaded and genistein-loaded exosome-like nanoparticles, using dynamic and electrophoretic light scattering. Our findings revealed that the presence of small lipophilic molecules, cholesterol and/or genistein, influenced the characteristics of the final formulations differently based on the development approach. Regardless of the initial differences of the formulations, all exosome-like nanoparticles, whether loaded with genistein or not, exhibited remarkable colloidal stability over time. Furthermore, an encapsulation efficiency of over 87% for genistein was achieved in all cases. Additionally, thermal analysis uncovered the presence of metastable phases within the membranes, which could impact the drug delivery efficiency. In summary, this study provides a comprehensive comparison between conventional and innovative methods for producing complex liposomal nanosystems, exemplified by exosome-like nanoparticles.


Assuntos
Exossomos , Nanopartículas , Microfluídica/métodos , Genisteína , Nanopartículas/química , Impressão Tridimensional
4.
J Clin Med ; 13(12)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38930033

RESUMO

Background: Diabetes is a rapidly growing global morbidity issue with high prevalence, and the associated dysglycemia leads to complications. Patients with type 2 diabetes mellitus (T2DM) often experience elevated anxiety levels, affecting their quality of life and diabetes management. This study investigated quercetin, a nutraceutical and potential senolytic with antioxidant activity, to detect its possible positive effect on the bio-clinical measurements and routine health of patients with T2DM. Methods: This prospective randomized controlled trial (RCT) investigated the clinical usefulness of quercetin in patients with T2DM receiving non-insulin medications. One hundred participants were stratified by age and sex (1:1) and randomized to control (n = 50) or intervention (n = 50) groups. The control received standard care only, while the intervention received 500 mg quercetin daily for 12 weeks, followed by an 8-week washout and a final consecutive 12-week supplementation period (total: 32 weeks), as adjunct to their usual care. Comprehensive health assessments, including blood analyses, were conducted at baseline and study termination. Quality of life and anxiety were assessed using the 36-item Short Form Health Survey (SF-36) and Short Anxiety Screening Test (SAST-10). Results: Eighty-eight patients with T2DM concluded the trial. Compared with the control, glycated hemoglobin (HbA1c) levels showed a significant decrease (Δ%-change: -4.0% vs. 0.1%, p = 0.011). Quercetin also significantly improved PiKo-6 readings (FEV1: 5.6% vs. -1.5%, p = 0.002), systolic blood pressure (-5.0% vs. -0.2%, p = 0.029), night-time sleep (11.6% vs. -7.3%, p < 0.001), anxiety levels (SAST-10) (-26.2% vs. 3.3%, p < 0.001), and quality of life (SF-36) (both physical and mental components, p < 0.001). Conclusions: Based on the current open-label study, quercetin appears to be a promising supplement for T2DM, providing lifestyle and care support. Further research is warranted to shift this potential from clinical usefulness and feasibility to multidisciplinary evidence.

5.
Front Pharmacol ; 13: 900610, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016560

RESUMO

RNA-delivery is a promising tool to develop therapies for difficult to treat diseases such as neurological disorders, by silencing pathological genes or expressing therapeutic proteins. However, in many cases RNA delivery requires a vesicle that could effectively protect the molecule from bio-degradation, bypass barriers i.e., the blood brain barrier, transfer it to a targeted tissue and efficiently release the RNA inside the cells. Many vesicles such as viral vectors, and polymeric nanoparticles have been mentioned in literature. In this review, we focus in the discussion of lipid-based advanced RNA-delivery platforms. Liposomes and lipoplexes, solid lipid nanoparticles and lipid nanoparticles are the main categories of lipidic platforms for RNA-delivery to the central nervous systems (CNS). A variety of surface particles' modifications and routes of administration have been studied to target CNS providing encouraging results in vivo. It is concluded that lipid-based nanoplatforms will play a key role in the development of RNA neuro-therapies.

6.
Plants (Basel) ; 11(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36559660

RESUMO

Chelmos-Vouraikos National Park is a floristic diversity and endemism hotspot in Greece and one of the main areas where Greek endemic taxa, preliminary assessed as critically endangered and threatened under the IUCN Criteria A and B, are mainly concentrated. The climate and land-cover change impacts on rare and endemic species distributions is more prominent in regional biodiversity hotspots. The main aims of the current study were: (a) to investigate how climate and land-cover change may alter the distribution of four single mountain endemics and three very rare Peloponnesian endemic taxa of the National Park via a species distribution modelling approach, and (b) to estimate the current and future extinction risk of the aforementioned taxa based on the IUCN Criteria A and B, in order to investigate the need for designing an effective plant micro-reserve network and to support decision making on spatial planning efforts and conservation research for a sustainable, integrated management. Most of the taxa analyzed are expected to continue to be considered as critically endangered based on both Criteria A and B under all land-cover/land-use scenarios, GCM/RCP and time-period combinations, while two, namely Alchemilla aroanica and Silene conglomeratica, are projected to become extinct in most future climate change scenarios. When land-cover/land-use data were included in the analyses, these negative effects were less pronounced. However, Silene conglomeratica, the rarest mountain endemic found in the study area, is still expected to face substantial range decline. Our results highlight the urgent need for the establishment of micro-reserves for these taxa.

7.
Int J Pharm ; 610: 121212, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34687816

RESUMO

While classic vaccines have proved greatly efficacious in eliminating serious infectious diseases, innovative vaccine platforms open a new pathway to overcome dangerous pandemics via the development of safe and effective formulations. Such platforms play a key role either as antigen delivery systems or as immune-stimulators that induce both innate and adaptive immune responses. Liposomes or lipid nanoparticles, virus-like particles, nanoemulsions, polymeric or inorganic nanoparticles, as well as viral vectors, all belong to the nanoscale and are the main categories of innovative vaccines that are currently on the market or in clinical and preclinical phases. In this paper, we review the above formulations used in vaccinology and we discuss their connection with the development of safe and effective prophylactic vaccines against SARS-CoV-2.


Assuntos
COVID-19 , Doenças Transmissíveis , Vacinas , Vacinas contra COVID-19 , Humanos , Lipossomos , Nanopartículas , Pandemias/prevenção & controle , SARS-CoV-2
8.
Surg Infect (Larchmt) ; 9(5): 521-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18983229

RESUMO

PURPOSE: To evaluate the prevalence of bacteremia after mask ventilation, laryngoscopy, and endotracheal intubation before induction of general anesthesia and to discover any correlation between traumatic manipulations and bacteremia. The specific bacteria responsible, knowledge of which may guide the prophylactic use of antibiotics, also were investigated. METHODS: Fifty patients were enrolled. Three 10-mL blood samples were collected from a peripheral vein 10 min before induction of anesthesia, 10 min after mask ventilation, and 10 min after intubation. All samples were placed in aerobic and anaerobic bottles for culture and bacterial identification. RESULTS: Cultures received 10 min after intubation were positive in 12% of patients. The following strains were isolated: Escherichia coli in two cases, Staphylococcus aureus in three cases, and Peptostreptococcus anaerobius in one case. A strong positive correlation was found between difficult intubation and bacteremia. No correlation between bacteremia and easy intubation or between bacteremia and face mask ventilation was identified. CONCLUSION: Traumatic manipulations during difficult laryngoscopy and endotracheal intubation could cause bacteremia. This finding may justify and guide prophylactic use of antibiotics.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/etiologia , Intubação Intratraqueal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Bacteriemia/microbiologia , Bacteriemia/prevenção & controle , Sangue/microbiologia , Meios de Cultura , Escherichia coli/isolamento & purificação , Humanos , Incidência , Laringoscopia/efeitos adversos , Pessoa de Meia-Idade , Peptostreptococcus/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Adulto Jovem
9.
Environ Pollut ; 211: 282-90, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26774775

RESUMO

Results from coastal water pollution monitoring (Lesvos Island, Greece) are presented. In total, 53 samples were analyzed for 58 polar organic micropollutants such as selected herbicides, biocides, corrosion inhibitors, stimulants, artificial sweeteners, and pharmaceuticals. Main focus is the application of a proposed wastewater indicator quartet (acesulfame, caffeine, valsartan, and valsartan acid) to detect point sources and contamination hot-spots with untreated and treated wastewater. The derived conclusions are compared with the state of knowledge regarding local land use and infrastructure. The artificial sweetener acesulfame and the stimulant caffeine were used as indicators for treated and untreated wastewater, respectively. In case of a contamination with untreated wastewater the concentration ratio of the antihypertensive valsartan and its transformation product valsartan acid was used to further refine the estimation of the residence time of the contamination. The median/maximum concentrations of acesulfame and caffeine were 5.3/178 ng L(-1) and 6.1/522 ng L(-1), respectively. Their detection frequency was 100%. Highest concentrations were detected within the urban area of the capital of the island (Mytilene). The indicator quartet in the gulfs of Gera and Kalloni (two semi-enclosed embayments on the island) demonstrated different concentration patterns. A comparatively higher proportion of untreated wastewater was detected in the gulf of Gera, which is in agreement with data on the wastewater infrastructure. The indicator quality of the micropollutants to detect wastewater was compared with electrical conductivity (EC) data. Due to their anthropogenic nature and low detection limits, the micropollutants are superior to EC regarding both sensitivity and selectivity. The concentrations of atrazine, diuron, and isoproturon did not exceed the annual average of their environmental quality standards (EQS) defined by the European Commission. At two sampling locations irgarol 1051 exceeded its annual average EQS value but not the maximum allowable concentration of 16 ng L(-1).


Assuntos
Água do Mar/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Atrazina , Desinfetantes/análise , Diurona , Grécia , Herbicidas/análise , Edulcorantes , Qualidade da Água
10.
Int J Environ Res Public Health ; 11(10): 10390-405, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25310538

RESUMO

Attenuation of micro-contaminants is a very complex field in environmental science and evidence suggests that biodegradation rates of micro-contaminants in the aqueous environment depend on the water matrix. The focus of the study presented here is the systematic comparison of biotransformation rates of caffeine, carbamazepine, metoprolol, paracetamol and valsartan in river water microcosms spiked with different proportions of treated effluent (0%, 0.1%, 1%, and 10%). Biotransformation was identified as the dominating attenuation process by the evolution of biotransformation products such as atenolol acid and valsartan acid. Significantly decreasing biotransformation rates of metoprolol were observed at treated effluent proportions ≥ 0.1% whereas significantly increasing biotransformation rates of caffeine and valsartan were observed in the presence of 10% treated effluent. Potential reasons for the observations are discussed and the addition of adapted microorganisms via the treated effluent was suggested as the most probable reason. The impact of additional phosphorus on the biodegradation rates was tested and the experiments revealed that phosphorus-limitation was not responsible.


Assuntos
Rios/química , Poluentes Químicos da Água/metabolismo , Acetaminofen/metabolismo , Biotransformação , Cafeína/metabolismo , Carbamazepina/metabolismo , Metoprolol/metabolismo , Preparações Farmacêuticas , Rios/microbiologia , Esgotos/análise , Esgotos/química , Tetrazóis/metabolismo , Valina/análogos & derivados , Valina/metabolismo , Valsartana , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise
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