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1.
Mar Drugs ; 21(4)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37103346

RESUMO

The wound-healing process is a significant area of interest in the medical field, and it is influenced by both external and patient-specific factors. The aim of this review paper is to highlight the proven wound-healing potential of the biocompounds found in jellyfish (such as polysaccharide compounds, collagen, collagen peptides and amino acids). There are aspects of the wound-healing process that can benefit from polysaccharides (JSPs) and collagen-based materials, as these materials have been shown to limit exposure to bacteria and promote tissue regeneration. A second demonstrated benefit of jellyfish-derived biocompounds is their immunostimulatory effects on growth factors such as (TNF-α), (IFN-γ) and (TGF), which are involved in wound healing. A third benefit of collagens and polysaccharides (JSP) is their antioxidant action. Aspects related to chronic wound care are specifically addressed, and within this general theme, molecular pathways related to tissue regeneration are explored in depth. Only distinct varieties of jellyfish that are specifically enriched in the biocompounds involved in these pathways and live in European marine habitats are presented. The advantages of jellyfish collagens over mammalian collagens are highlighted by the fact that jellyfish collagens are not considered transmitters of diseases (spongiform encephalopathy) or various allergic reactions. Jellyfish collagen extracts stimulate an immune response in vivo without inducing allergic complications. More studies are needed to explore more varieties of jellyfish that can be exploited for their biocomponents, which may be useful in wound healing.


Assuntos
Cnidários , Cifozoários , Animais , Humanos , Cnidários/metabolismo , Cicatrização , Cifozoários/química , Colágeno/química , Antioxidantes/farmacologia , Mamíferos/metabolismo
2.
Int J Mol Sci ; 24(6)2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36982751

RESUMO

In this paper, we report the synthesis of ZnO nanoparticles (NPs) by forced solvolysis of Zn(CH3COO)2·2H2O in alcohols with a different number of -OH groups. We study the influence of alcohol type (n-butanol, ethylene glycol and glycerin) on the size, morphology, and properties of the obtained ZnO NPs. The smallest polyhedral ZnO NPs (<30 nm) were obtained in n-butanol, while in ethylene glycol the NPs measured on average 44 nm and were rounded. Polycrystalline particles of 120 nm were obtained in glycerin only after water refluxing. In addition, here, we report the photocatalytic activity, against a dye mixture, of three model pollutants: methyl orange (MO), methylene blue (MB), and rhodamine B (RhB), a model closer to real situations where water is polluted with many chemicals. All samples exhibited good photocatalytic activity against the dye mixture, with degradation efficiency reaching 99.99%. The sample with smallest nanoparticles maintained a high efficiency >90%, over five catalytic cycles. Antibacterial tests were conducted against Gram-negative strains Salmonella enterica serovar Typhimurium, Pseudomonas aeruginosa, and Escherichia coli, and Gram-positive strains Enterococcus faecalis, Bacillus subtilis, Staphylococcus aureus, and Bacillus cereus. The ZnO samples presented strong inhibition of planktonic growth for all tested strains, indicating that they can be used for antibacterial applications, such as water purification.


Assuntos
Nanopartículas Metálicas , Óxido de Zinco , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Nanopartículas Metálicas/química , Azul de Metileno/farmacologia , Azul de Metileno/química , 1-Butanol , Glicerol , Antibacterianos/química , Água , Etilenoglicóis
3.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069172

RESUMO

This study aimed to investigate, for the first time, the chemical composition and antioxidant activity of fluid extracts obtained from three Romanian cultivars of haskap berries (Lonicera caerulea L.) var. Loni, bitter cherries (Prunus avium var. sylvestris Ser.) var. Silva, and pomace from red grapes (Vitis vinifera L.) var. Mamaia, and their capacity to modulate in vitro steatosis, in view of developing novel anti-obesity products. Total phenolic, flavonoid, anthocyanin, and ascorbic acid content of fluid extracts was spectrophotometrically assessed and their free radical scavenging capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and free 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition assays. The Pearson coefficients showed a moderate correlation between the antioxidant activity of fluid extracts and their phenolic content, but a strong correlation between anthocyanin and ascorbic acid content. HPLC analysis identified and quantified the main phenolic compounds of chlorogenic and syringic acid, catechin, and glycosylated kaempferol, apigenin, and quercetin, in variable proportions. An in vitro experimental model of steatosis was developed in HepG2 hepatocytes treated with a mixture of free fatty acids. Cell culture analyses showed that cytocompatible concentrations of fluid extracts could significantly reduce the lipid accumulation and inhibit the reactive oxygen species, malondialdehyde, and nitric oxide secretion in stressed hepatocytes. In conclusion, these results put an emphasis on the chemical compounds' high antioxidant and liver protection capacity of unstudied fluid extracts obtained from Romanian cultivars of bitter cherries var. Silva and pomace of red grapes var. Mamaia, similar to the fluid extract of haskap berries var. Loni, in particular, the positive modulation of fat deposition next to oxidative stress and the lipid peroxidation process triggered by fatty acids in HepG2 hepatocytes. Consequently, this study indicated that these fluid extracts could be further exploited as hepatoprotective agents in liver steatosis, which provides a basis for the further development of novel extract mixtures with synergistic activity as anti-obesity products.


Assuntos
Fígado Gorduroso , Vitis , Antioxidantes/química , Frutas/química , Antocianinas/química , Romênia , Extratos Vegetais/química , Ácido Ascórbico/química , Fenóis/química , Fígado Gorduroso/tratamento farmacológico
4.
Mar Drugs ; 20(11)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36354993

RESUMO

Fabrication of three-dimensional (3D) scaffolds using natural biomaterials introduces valuable opportunities in bone tissue reconstruction and regeneration. The current study aimed at the development of paste-like 3D printing inks with an extracellular matrix-inspired formulation based on marine materials: sodium alginate (SA), cuttlebone (CB), and fish gelatin (FG). Macroporous scaffolds with microporous biocomposite filaments were obtained by 3D printing combined with post-printing crosslinking. CB fragments were used for their potential to stimulate biomineralization. Alginate enhanced CB embedding within the polymer matrix as confirmed by scanning electron microscopy (ESEM) and micro-computer tomography (micro-CT) and improved the deformation under controlled compression as revealed by micro-CT. SA addition resulted in a modulation of the bulk and surface mechanical behavior, and lead to more elongated cell morphology as imaged by confocal microscopy and ESEM after the adhesion of MC3T3-E1 preosteoblasts at 48 h. Formation of a new mineral phase was detected on the scaffold's surface after cell cultures. All the results were correlated with the scaffolds' compositions. Overall, the study reveals the potential of the marine materials-containing inks to deliver 3D scaffolds with potential for bone regeneration applications.


Assuntos
Alginatos , Gelatina , Animais , Gelatina/farmacologia , Alginatos/farmacologia , Tinta , Alicerces Teciduais , Engenharia Tecidual/métodos , Impressão Tridimensional , Regeneração Óssea
5.
Int J Mol Sci ; 23(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35682664

RESUMO

The synthesis of nanoparticles from noble metals has received high attention from researchers due to their unique properties and their wide range of applications. Silver nanoparticles (AgNPs), in particular, show a remarkable inhibitory effect against microorganisms and viruses. Various methods have been developed to obtain AgNPs, however the stability of such nanostructures over time is still challenging. Researchers attempt to obtain particular shapes and sizes in order to tailor AgNPs properties for specific areas, such as biochemistry, biology, agriculture, electronics, medicine, and industry. The aim of this study was to design AgNPs with improved antimicrobial characteristics and stability. Two different wet chemical routes were considered: synthesis being performed (i) reduction method at room temperatures and (ii) solvothermal method at high temperature. Here, we show that the antimicrobial properties of the obtained AgNPs, are influenced by their synthesis route, which impact on the size and shape of the structures. This work analyses and compares the antimicrobial properties of the obtained AgNPs, based on their structure, sizes and morphologies which are influenced, in turn, not only by the type or quantities of precursors used but also by the temperature of the reaction. Generally, AgNPs obtained by solvothermal, at raised temperature, registered better antimicrobial activity as compared to NPs obtained by reduction method at room temperature.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Prata/química , Prata/farmacologia
6.
Medicina (Kaunas) ; 58(4)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35454303

RESUMO

Pre-procedure mitral regurgitation (MR) is a frequent coexistent finding in patients undergoing transcatheter aortic valve replacement (TAVR), and most of them (up to 55%) experience a significant improvement in MR after the procedure. Although seldom described, mitral valve perforation after TAVR is a potentially serious complication that physicians should be aware of, as moderate or severe MR in TAVR recipients is associated with a high early mortality rate. We herein describe the case of a 65-year-old man presenting with worsening heart failure symptoms 5 months after TAVR due to an intraprocedural anterior mitral leaflet perforation and discuss the diagnostic process and therapeutic course of the case. Furthermore, we draw attention to the essential role of echocardiography in the management of TAVR procedures, taking into account its ability in detecting early complications, and emphasize the value of CT as a main determinant to predict long-term MR improvement after TAVR and to assess the potential candidates for double valve repair with percutaneous techniques.


Assuntos
Estenose da Valva Aórtica , Insuficiência da Valva Mitral , Idoso , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Humanos , Masculino , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Índice de Gravidade de Doença , Resultado do Tratamento
7.
Europace ; 23(1): 149-156, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33503658

RESUMO

The aim of this European Heart Rhythm Association (EHRA) survey was to assess the utilization of same-day discharge (SDD) in electrophysiology (EP). An online-based questionnaire was shared with the EHRA community between 12 and 30 June 2020 and recorded institutional information, complication assessment, recent experiences, and opinions regarding possible advantages or concerns with SDD. In total, 218 responses from 49 countries provided information on current SDD management. Overall, SDD was implemented in 77.5%, whereas this proportion was significantly higher in tertiary and high-volume centres (83.8% and 85.3%, both P < 0.01). The concept of SDD was most commonly used following implantations of cardiac event recorders (97%), diagnostic EP procedures (72.2%), and implantations of pacemakers with one or two intracardiac leads (50%), while the lowest SDD utilization was observed after catheter ablations of left atrial or ventricular arrhythmias. Within SDD-experienced centres, ∼90% respondents stated that this discharge concept is recommendable or highly recommendable and reported that rates of increased rehospitalization and complication rates were low. Most respondents assumed a better utilization of hospital resources (78.2%), better cost effectiveness (77.3%), and an improved patients' comfort but were concerned about possible impairment of detection (72.5%) and management (78.7%) of late complications. In conclusion, >75% of respondents already implement SDD following EP interventions with a large heterogeneity with regard to specific procedures. Further research is needed to confirm or disprove existing and expected benefits and obstacles.


Assuntos
Ablação por Cateter , Alta do Paciente , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/terapia , Europa (Continente) , Humanos , Percepção , Inquéritos e Questionários
8.
Echocardiography ; 38(7): 1157-1164, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34028880

RESUMO

BACKGROUND: Right ventricular - arterial (RV-PA) coupling can be estimated by echocardiography using the ratio between (TAPSE) and pulmonary arterial systolic pressure (PASP). TAPSE/PASP ratio proved to be a prognostic parameter in patients with heart failure and reduced ejection fraction (HFrEF). OBJECTIVE: To evaluate the significance of RV-PA coupling in patients with HFrEF undergoing cardiac resynchronization therapy (CRT). METHODS: Patients undergoing CRT in our center between January 2017 and November 2019 were eligible. Response to CRT was defined by a reduction of more than 15% of left ventricle systolic volume (LVESV) one year after CRT. Primary endpoint was a composite of HF hospitalizations and death during follow-up. RESULTS: 54 patients (Age 64.0 ± 13.8 years; 58% male; left ventricular ejection fraction (LVEF) 28.4 ± 1.3%) were prospectively included. After a mean follow-up of 31 ± 12.9months, the primary endpoint had occurred in 18 (33.3%) patients. A lower TAPSE/PASP ratio was associated with baseline worse HF symptoms, lower LVEF and long-term less LV reverse remodeling (P < .05). After one year CRT improved RV systolic function (TAPSE, RV global longitudinal strain, P < .05), but not TAPSE/PASP ratio (P = .4). The ratio TAPSE/PASP (AUC=0.834) ≥ 0.58 mm/mm Hg showed good sensitivity (90%) and specificity (81.8%) for predicting response to CRT while a ratio <0.58 mm/mm Hg was associated with a higher risk of death and HF hospitalizations during the follow-up (HR 5.37 95%CI [1.6-18], P < .001). CONCLUSION: RV-PA coupling evaluation using TAPSE/PASP ratio predicts CRT response. A lower TAPSE/PASP ratio is associated with a higher risk of adverse cardiovascular events.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Idoso , Ecocardiografia Doppler , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/terapia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Volume Sistólico , Função Ventricular Esquerda , Função Ventricular Direita
9.
Europace ; 21(12): 1876-1889, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625553

RESUMO

AIMS: The present study sought to determine predictors for success and outcomes of patients who underwent cardiac implantable electronic devices (CIED) extraction indicated for systemic or local CIED related infection in particular where complete lead removal could not be achieved. METHODS AND RESULTS: ESC-EORP ELECTRa (European Lead Extraction ConTRolled Registry) is a European prospective lead extraction registry. Out of the total cohort, 1865/3510 (52.5%) patients underwent removal due to CIED related infection. Predictors and outcomes of failure were analysed. Complete removal was achieved in 1743 (93.5%) patients, partial (<4 cm of lead left) in 88 (4.7%), and failed (>4 cm of lead left) in 32 (1.8%) patients. Removal success was unrelated to type of CIED infection (pocket or systemic). Predictors for failure were older leads and older patients [odds ratio (OR) 1.14 (1.08-1.19), P < 0.0001 and OR 2.68 (1.22-5.91), P = 0.0146, respectively]. In analysis by lead, predictors for failure were: pacemaker vs. defibrillator removal and failure to engage the locking stylet all the way to the tip [OR 0.20 (0.04-0.95), P = 0.03 and OR 0.32 (0.13-0.74), P = 0.008, respectively]. Significantly higher complication rates were noted in the failure group (40.6% vs. 15.9 for partial and 8.7% for success groups, P < 0.0001). Failure to remove a lead was a strong predictor for in hospital mortality [hazard ratio of 2.05 (1.01-4.16), P = 0.046]. CONCLUSION: A total of 6.5% of infected CIED patients failed attempted extraction. Only were >4 cm of lead remained resulted in higher procedural complications and mortality rates.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Remoção de Dispositivo/estatística & dados numéricos , Marca-Passo Artificial , Infecções Relacionadas à Prótese/terapia , Fatores Etários , Idoso , Antibacterianos/uso terapêutico , Eletrodos Implantados , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Tempo , Falha de Tratamento , Resultado do Tratamento
10.
Lasers Surg Med ; 48(3): 281-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26696586

RESUMO

BACKGROUND: Current lead extraction (LE) devices can harm the blood vessel endothelium, increasing the risk of perforation. OBJECTIVE: Proof of concept for using a solid-state pulsed laser at 355 nm with a hybrid catheter in LE. METHODS: A hybrid catheter was used comprising optical fibers for the delivery of 355 nm laser pulses at 30 Hz and 6 J/cm(2) combined with a blunt mechanical blade. Specific parameters were chosen to enable selectivity in ablation, thereby reducing the risk of blood vessel perforation. The design exploits differences in the mechanical properties of the fibrotic tissue and the normal blood vessel. Ex vivo ablation was performed to evaluate a hybrid catheter operation on various tissues. Two ex/in vivo pig studies used a free-floating electrode to which three bovine tendon pieces were glued. Finally, two in vivo dog model studies were performed on specimens with 4-5-year-old pacing lead implants, followed by a histopathology study. RESULTS: Catheter penetration rate in the ex vivo experiments was 0.1 mm/seconds for bovine tendon, 0.025 mm/seconds for porcine superior vena cava and 0.033 mm/seconds for porcine aorta. In the ex/in vivo pig study, the three tissue blocks were successfully dissected. In the in vivo dog study, the two leads were successfully extracted. In all in vivo tests, hemodynamic stability was maintained. Gross histopathology did not reveal any injury. CONCLUSIONS: Ablation using 355 nm laser pulses in combination with a mechanical blunt blade may potentially constitute a viable alternative for LE.


Assuntos
Ablação por Cateter/métodos , Catéteres , Desfibriladores Implantáveis , Remoção de Dispositivo/métodos , Endotélio Vascular/cirurgia , Lasers de Estado Sólido/uso terapêutico , Animais , Ablação por Cateter/instrumentação , Bovinos , Remoção de Dispositivo/instrumentação , Cães , Feminino , Suínos
11.
Am J Nephrol ; 42(4): 295-304, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26529418

RESUMO

BACKGROUND: Renal dysfunction is associated with increased mortality in heart failure (HF) patients. However, there are limited data regarding clinical and arrhythmic outcomes associated with implantable cardioverter defibrillator (ICD) therapy in this population. METHODS: We evaluated outcomes associated with the severity of renal dysfunction with or without dialysis among 2,289 patients who were enrolled and prospectively followed up in the Israeli ICD Registry. The primary endpoint of the study was all-cause mortality. Secondary endpoints included cardiac mortality, HF hospitalization, non-cardiac hospitalization, and appropriate and inappropriate ICD therapy. RESULTS: Severe renal dysfunction patients (estimated glomerular filtration rate<30 ml/min/1.73 m2; n=144 patients; 6%) were older, with higher comorbidities prevalence, and more likely to suffer from advanced HF. Among severe renal dysfunction patients, those on dialysis had a lower prevalence of wide QRS and complete left bundle branch morphology, resulting in lower cardiac resynchronization therapy defibrillator (CRTD) implantation rates. Dialysis was associated with an overall increased risk for all-cause mortality (hazard ratio (HR) 3.22; 95% CI 1.69-6.13; p<0.01) and for noncardiac hospitalizations (HR 2.80; p<0.001) compared to all other study patients. However, within the subgroup of patients with severe renal dysfunction, the presence of dialysis was not an independent risk factor for all-cause mortality (HR 0.99; p=0.97) as compared to non-dialysis. The rate of appropriate ICD therapy for ventricular tachyarrhythmias increased with declining renal function, with the highest rate observed among those undergoing dialysis. CONCLUSIONS: The present findings suggest that dialysis does not significantly modify the adverse outcomes associated with severe renal dysfunction following ICD/CRTD implantation.


Assuntos
Arritmias Cardíacas/terapia , Dispositivos de Terapia de Ressincronização Cardíaca , Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Insuficiência Cardíaca/terapia , Falência Renal Crônica/complicações , Implantação de Prótese , Sistema de Registros , Idoso , Arritmias Cardíacas/complicações , Feminino , Taxa de Filtração Glomerular , Insuficiência Cardíaca/complicações , Hospitalização , Humanos , Estimativa de Kaplan-Meier , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/complicações , Isquemia Miocárdica/terapia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Diálise Renal , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia , Índice de Gravidade de Doença , Volume Sistólico
12.
J Cardiovasc Electrophysiol ; 25(11): 1188-95, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24891182

RESUMO

INTRODUCTION: Renal dysfunction is associated with increased morbi-mortality in heart failure patients. Data regarding functional and clinical efficacy of cardiac resynchronization therapy (CRT) in this population are limited. METHODS AND RESULTS: We aimed to evaluate the rate of functional response to CRT in patients with renal dysfunction and its association with long-term mortality. Our study included a total of 179 consecutive patients implanted between 2007 and 2010. The rate of functional response to CRT (defined by a composite score using New York Heart Association functional class, 6-minute walk test, and quality of life) was compared between patients with and without renal dysfunction (defined as eGFR < or ≥60 mL/min/1.73 m(2) ). Survival analysis estimates were constructed according to the Kaplan-Meier method, with results comparison using the log-rank test. During a median follow-up of 4.2 years, 73 patients (40%) died. Patients with low eGFR were older (72 ± 8 years vs. 64 ± 12 years; P < 0.001), and had higher prevalence of ischemic heart disease (75% vs. 53%; P = 0.003). Functional response rates did not differ significantly between patients with and without renal dysfunction (58% and 69%, respectively; P = 0.14). Despite overall higher mortality in patients with low eGFR (53.8% vs. 22.7%; P < 0.001), the presence of functional response at 1 year among patients with renal dysfunction was still independently associated with an improved long-term survival (HR = 0.49 [95%CI: 0.28-0.83]; P = 0.009). CONCLUSION: Functional response to CRT at 1 year does not differ significantly between patients with or without kidney disease, and is an independent predictor of improved long-term survival in patients with renal dysfunction.


Assuntos
Terapia de Ressincronização Cardíaca/mortalidade , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Nefropatias/mortalidade , Nefropatias/terapia , Idoso , Idoso de 80 Anos ou mais , Terapia de Ressincronização Cardíaca/métodos , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular/fisiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Nefropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Fatores de Tempo , Resultado do Tratamento
13.
Photochem Photobiol Sci ; 13(4): 703-16, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24590004

RESUMO

The aim of this research was to develop advanced lipid nanocarriers based on renewable vegetable resources (rice bran oil and raspberry seed oil) that possess self-antioxidative properties, having advantages in terms of minimal side effects and exhibiting the ability to simultaneously co-encapsulate and co-release two active compounds. The focus has been oriented towards developing safe cosmetic formulations with broad-spectrum photoprotection based on these new lipid nanocarriers that contain large amounts of vegetable oils and low concentrations of synthetic UVA and UVB filters (butyl-methoxydibenzoylmethane - BMDBM and octocrylene - OCT). The lipid nanocarriers have a spherical shape and show good physical stability, with a zeta potential in the range of -25.5 to -32.4 mV. Both vegetable oils play a key role in the preparation of efficient nanocarriers, leading to a less ordered arrangement of the lipid core that offers many spaces for the entrapment of large amounts of BMDBM (79%) and OCT (90%), as wells as improved antioxidant activity and UV absorption properties, particularly for the lipid nanocarriers prepared from rice bran oil. By formulating the lipid nanocarriers into creams containing only 3.5% of the UV filters and 10.5% of the vegetable oils, the resulting sunscreens exhibited improved photoprotection, reflecting up to 91% and 93% of UVA and UVB rays, respectively. A new direction of research achieved by this study is the multiple release strategy of both UV filters from the same lipid nanocarrier. After 24 hours, a slow release of BMDBM (less than 4%) and OCT (17.5%) was obtained through a Fick diffusion process. This study demonstrates a significant advance in the areas of both nanotechnology and cosmetics, developing safer cosmetic formulations that possess broad antioxidant, photoprotective and co-release effectiveness due to the existence of a high content of nanostructured vegetable oils combined with a low amount of synthetic UV filters in the same carrier system.


Assuntos
Frutas/química , Nanocápsulas/química , Oryza/química , Óleos de Plantas/química , Sementes/química , Protetores Solares/química , Absorção de Radiação , Acrilatos/química , Alcanos/química , Antioxidantes/química , Chalconas/química , Química Farmacêutica , Cosméticos/química , Cristalização , Difusão , Estabilidade de Medicamentos , Cinética , Lipídeos/química , Tamanho da Partícula , Processos Fotoquímicos , Propiofenonas , Raios Ultravioleta
17.
Molecules ; 19(4): 5013-27, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24759068

RESUMO

This paper reports the synthesis and characterization of amoxicillin- functionalized magnetite nanostructures (Fe3O4@AMO), revealing and discussing several biomedical applications of these nanomaterials. Our results proved that 10 nm Fe3O4@AMO nanoparticles does not alter the normal cell cycle progression of cultured diploid cells, and an in vivo murine model confirms that the nanostructures disperse through the host body and tend to localize in particular sites and organs. The nanoparticles were found clustered especially in the lungs, kidneys and spleen, next to the blood vessels at this level, while being totally absent in the brain and liver, suggesting that they are circulated through the blood flow and have low toxicity. Fe3O4@AMO has the ability to be easily circulated through the body and optimizations may be done so these nanostructures cluster to a specific target region. Functionalized magnetite nanostructures proved a great antimicrobial effect, being active against both the Gram positive pathogen S. aureus and the Gram negative pathogen E. coli. The fabricated nanostructures significantly reduced the minimum inhibitory concentration (MIC) of the active drug. This result has a great practical relevance, since the functionalized nanostructures may be used for decreasing the therapeutic doses which usually manifest great severe side effects, when administrated in high doses. Fe3O4@AMO represents also a suitable approach for the development of new alternative strategies for improving the activity of therapeutic agents by targeted delivery and controlled release.


Assuntos
Amoxicilina/farmacologia , Antibacterianos/farmacologia , Óxido Ferroso-Férrico/química , Óxido Ferroso-Férrico/farmacologia , Nanopartículas de Magnetita/química , Amoxicilina/química , Amoxicilina/farmacocinética , Animais , Antibacterianos/química , Antibacterianos/farmacocinética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Portadores de Fármacos , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Óxido Ferroso-Férrico/farmacocinética , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Nanopartículas de Magnetita/toxicidade , Camundongos , Tamanho da Partícula , Baço/efeitos dos fármacos , Baço/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
18.
Molecules ; 19(8): 12011-30, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25120054

RESUMO

Novel derivatives were prepared by reaction of aromatic amines with 2-(4-ethylphenoxymethyl)benzoyl isothiocyanate, affording the N-[2-(4-ethylphenoxymethyl) benzoyl]-Nꞌ-(substituted phenyl)thiourea. Structural elucidation of these compounds was performed by IR, NMR spectroscopy and elemental analysis. The new compounds were used in combination with Fe3O4 and polyvinylpyrrolidone (PVP) for the coating of medical surfaces. In our experiments, catheter pieces were coated by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. The microbial adherence ability was investigated in 6 multi-well plates by using culture based methods. The obtained surfaces were also assessed for their cytotoxicity with respect to osteoblast cells, by using fluorescence microscopy and MTT assay. The prepared surfaces by advanced laser processing inhibited the adherence and biofilm development ability of Staphylococcus aureus and Pseudomonas aeruginosa tested strains while cytotoxic effects on the 3T3-E1 preosteoblasts embedded in layer shaped alginate hydrogels were not observed. These results suggest that the obtained medical surfaces, based on the novel thiourea derivatives and magnetic nanoparticles with a polymeric shell could represent a promising alternative for the development of new and effective anti-infective strategies.


Assuntos
Antibacterianos/química , Benzamidas/química , Biofilmes/efeitos dos fármacos , Compostos de Ferro/química , Polivinil/química , Pirrolidinas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Benzamidas/síntese química , Benzamidas/farmacologia , Biofilmes/crescimento & desenvolvimento , Humanos , Compostos de Ferro/farmacologia , Espectroscopia de Ressonância Magnética , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Polivinil/síntese química , Polivinil/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pirrolidinas/síntese química , Pirrolidinas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
19.
Biomedicines ; 12(3)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38540108

RESUMO

INTRODUCTION: Prognosis after electrical storm (ES) ablation remains severe, especially in patients with recurrent sustained monomorphic ventricular tachycardia (SMVT) or progressive heart failure (HF). However, single-factor-based prediction is suboptimal and may be refined by more complex algorithms. We sought to evaluate if a novel score MSA-VT (M = moderate/severe mitral regurgitation, S = severe HF at admission, A = atrial fibrillation at admission, VT = inducible SMVT after ablation) may improve prediction of death and recurrences compared to single factors and previous scores (PAINESD, RIVA and I-VT). METHODS: A total of 101 consecutive ES ablation patients were retrospectively analyzed over a 32.8-month (IQR 10-68) interval. The MSA-VT score was calculated as the sum of the previously mentioned factors' coefficients based on hazard ratio values in Cox regression analysis. The AUC for death prediction by MSA-VT was 0.84 (p < 0.001), superior to PAINESD (AUC 0.63, p = 0.03), RIVA (AUC 0.69, p = 0.02) and I-VT (0.56, p = 0.3). MSA-VT ≥ 3 was associated with significantly higher mortality during follow-up (52.7%, p < 0.001). CONCLUSIONS: Prediction by single factors and previously published scores after ES ablation may be improved by the novel MSA-VT score; however, this requires further external validation in larger samples.

20.
Int J Pharm ; 661: 124420, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971512

RESUMO

Colorectal cancer represents a worldwide spread type of cancer and it is regarded as one of the leading death causes, along with lung, breast, and prostate cancers. Since conventional surgical resection and chemotherapy proved limited efficiency, the use of alternative drug delivery systems that ensure the controlled release of cytostatic agents possess immense potential for treatment. In this regard, the present study aimed to develop and evaluate the efficiency of a series of irinotecan-loaded magnetite-silica core-shell systems. The magnetite particles were obtained through a solvothermal treatment, while the silica shell was obtained through the Stöber method directly onto the surface of magnetite particles. Subsequently, the core-shell systems were physico-chemically and morpho-structurally evaluated trough X-ray diffraction (XRD) and (high-resolution) transmission electron microscopy ((HR-)TEM) equipped with a High Annular Angular Dark Field Detector (HAADF) for elemental mapping. After the irinotecan loading, the drug delivery systems were evaluated through Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry and differential scanning calorimetry (TG-DSC), and UV-Vis spectrophotometry. Additionally, the Brunauer-Emmett-Teller (BET) method was employed for determining the surface area and pore volume of the systems. The biological functionality of the core-shells was investigated through the MTT assay performed on both normal and cancer cells. The results of the study confirmed the formation of highly crystalline magnetite particles comprising the core and mesoporous silica layers of sizes varying between 2 and 7 nm as the shell. Additionally, the drug loading and release was dependent on the type of the silica synthesis procedure, since the lack of hexadecyltrimethylammonium bromide (CTAB) resulted in higher drug loading but lower cumulative release. Moreover, the nanostructured systems demonstrated a targeted efficiency towards HT-29 colorectal adenocarcinoma cells, as in the case of normal L929 fibroblast cells, the cell viability was higher than for the pristine drug. In this manner, this study provides the means and procedures for developing drug delivery systems with applicability in the treatment of cancer.

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