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1.
BMC Cardiovasc Disord ; 24(1): 4, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166554

RESUMO

BACKGROUND AND AIM: Interventional cardiologists face challenges in managing chronic total occlusion (CTO) lesions, with conflicting results when comparing rotational atherectomy (RA) to conventional PCI. This meta-analysis aims to provide a critical evaluation of the safety and feasibility of RA in CTO lesions. METHODS: PubMed, Scopus, Web of Science, Ovid, and Cochrane central library until April 2023 were searched for relevant studies. MACE was our primary outcomes, other outcomes were all cause of death, cardiac death, MI, and TVR. Also, we reported angiographic outcomes as technical success, procedural success, and procedural complications in a random effect model. The pooled data was analyzed using odds ratio (OR) with its 95% CI using STATA 17 MP. RESULTS: Seven studies comprising 5494 patients with a mean follow-up of 43.1 months were included in this meta-analysis. Our pooled analysis showed that RA was comparable to PCI to decrease the incidence of MACE (OR = 0.98, 95% CI [0.74 to 1.3], p = 0.9). Moreover, there was no significant difference between RA and conventional PCI in terms of other clinical or angiographic outcomes. CONCLUSION: Our study showed that RA had comparable clinical and angiographic outcomes as conventional PCI in CTO lesions, which offer interventional cardiologists an expanded perspective when addressing calcified lesions. PROSPERO REGISTRATION: CRD42023417362.


Assuntos
Aterectomia Coronária , Oclusão Coronária , Intervenção Coronária Percutânea , Humanos , Doença Crônica , Oclusão Coronária/diagnóstico por imagem , Oclusão Coronária/cirurgia , Estudos de Viabilidade , Intervenção Coronária Percutânea/métodos , Fatores de Risco , Resultado do Tratamento
2.
Curr Probl Cardiol ; 48(11): 101890, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37336307

RESUMO

The use of percutaneous coronary intervention (PCI) in patients with chronic total occlusion (CTO) is still a subject of debate, with conflicting outcomes reported in different studies when compared to non-CTO lesions. This meta-analysis aims to clarify the clinical outcomes of PCI in CTO cases compared to non-CTO lesions, both in the short and long-term. PubMed, Scopus, Web of Science, Ovid, and Cochrane Central were searched until March 2023 for relevant studies addressing short- and long-term outcomes of PCI in CTO vs non-CTO lesions. Dichotomous data were pooled as odds ratio (OR) with its 95% confidence interval (CI) in a random Der-Simonian lair effect model using STATA 17 MP. Eight studies with a total of 690,123 patients were included. In terms of short-term outcomes, CTO PCI was associated with higher rates of vessel perforation (OR = 2.16, 95% CI: 1.31-3.57) and cardiac tamponade (OR = 5.19, 95% CI: 4.29-6.28). Additionally, CTO PCI showed lower rates of procedural success (OR = 0.84, 95% CI: 0.73-0.96). Moreover, in the long-term, CTO PCI had higher rates of MACE (OR = 1.02, 95% CI: 1.01-1.04), however, it showed lower rates of cardiac death (OR = 0.61, 95% CI: 0.38-0.98), with no significant difference in other reported outcomes. Our findings underscore the challenges and adverse outcomes associated with using PCI to treat CTO lesions in the short term. This suggests that interventional cardiologists should carefully evaluate the risks and benefits before proceeding with PCI in CTO lesions.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Humanos , Oclusão Coronária/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , Doença Crônica , Razão de Chances , Resultado do Tratamento , Fatores de Risco
3.
Sci Rep ; 13(1): 1927, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732552

RESUMO

In the current work, rice straw nanofibers (RSNF) with the width of elementary fibrils (~ 4-5 nm) were isolated from rice straw. The isolated nanofibers were used with zinc oxide nanoparticles (ZnONPs) to prepare flexible nanopaper films. Tensile strength and electrical properties of the prepared RSNF/ZnONPs nanopaper were investigated. The addition of ZnONPs to RSNF nanopaper did not deteriorate its mechanical properties and showed a slight improvement in tensile strength and Young's modulus of about 14% and 10%, respectively, upon the addition of 5% of ZnONPs. Microscopy investigation using scanning electron microscopy (SEM) showed the inclusion of the ZnONPs within the RSNF. Electrical conductivity and dielectric properties as a function of frequency at different temperatures were studied. The ac-electrical conductivity increased with frequency and fitted with the power law equation. The dc- electrical conductivity of the samples verified the Arrhenius equation and the activation energies varied in the range from 0.9 to 0.42 eV. The dielectric constant decreased with increasing frequency and increased with increasing temperature, probably due to the free movement of dipole molecular chains within the RSNF nanopaper. The high values of the dielectric constant and conductivity of the prepared nanopaper films support their use in electronic components.

4.
Polymers (Basel) ; 14(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36365599

RESUMO

Bio-based polymer composites find increasing research and industrial interest in different areas of our life. In this study, cellulose nanofibers (CNFs) isolated from sugar beet pulp and nanoemulsion prepared from sugar beet pectin and pomegranate extract (PGE) were used for making films and used as coating with antioxidant and antimicrobial activities for paper. For Pectin/PGE nanoemulsion preparation, different ratios of PGE were mixed with pectin using ultrasonic treatment; the antibacterial properties were evaluated to choose the formula with the adequate antibacterial activity. The antioxidant activity of the nanoemulsion with the highest antimicrobial activity was also evaluated. The nanoemulsion with the optimum antibacterial activity was mixed with different ratios of CNFs. Mechanical, greaseproof, antioxidant activity, and antibacterial properties of the CNFs/Pectin/PGE films were evaluated. Finally, the CNFs/Pectin/PGE formulation with the highest antibacterial activity was tested as a coating material for paper. Mechanical, greaseproof, and air porosity properties, as well as water vapor permeability and migration of the coated layer from paper sheets in different media were evaluated. The results showed promising applicability of the CNFs/Pectin/PGE as films and coating material with antibacterial and antioxidant activities, as well as good stability for packaging aqueous, fatty, and acidic food products.

5.
Sci Rep ; 10(1): 11278, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647119

RESUMO

There has been an increasing interest in recent years in isolating cellulose nanofibers from unbleached cellulose pulps for economic, environmental, and functional reasons. In the current work, cellulose nanofibers isolated from high-lignin unbleached neutral sulfite pulp were compared to those isolated from bleached rice straw pulp in making thin-film ultrafiltration membranes by vacuum filtration on hardened filter paper. The prepared membranes were characterized in terms of their microscopic structure, hydrophilicity, pure water flux, protein fouling, and ability to remove lime nanoparticles and purify papermaking wastewater effluent. Using cellulose nanofibers isolated from unbleached pulp facilitated the formation of a thin-film membrane (with a shorter filtration time for thin-film formation) and resulted in higher water flux than that obtained using nanofibers isolated from bleached fibers, without sacrificing its ability to remove the different pollutants.

6.
Int J Biol Macromol ; 113: 616-622, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29481954

RESUMO

Bioactive films from hydroxypropyl methylcellulose (HPMC), nisin (N), and different percentage (5% to 75%) of TEMPO-oxidized nanofibrillated cellulose (NFC) isolated from rice straw pulp were prepared by solution casting technique and their properties were studied. Scanning electron microscope images (SEM) of films showed homogeneous surface with absence of nanofibers agglomeration. The mechanical and barrier properties were evaluated by measuring their tensile strength, tensile modulus, strain at maximum load, dynamic mechanical thermal properties (DMTA), and water vapor permeability (WVP). In all films, there was an improvement in the mechanical, thermomechanical, and moisture barrier properties as a result of presence of NFC. The molecular structure of the films was studied by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction patterns (XRD). Presence of NFC in HPMC films affected crystallinity of the later. The prepared HPMC/N, NFC/N, and HPMC/N/NFC films exhibited significant antimicrobial activities against Gram-positive bacteria Staphylococcus aureus with noticeable controlled release of nisin in case of films containing HPMC/NFC.


Assuntos
Óxidos N-Cíclicos/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Derivados da Hipromelose/química , Fenômenos Mecânicos , Nanofibras/química , Nisina/química , Nanocompostos/química , Oxirredução , Permeabilidade , Vapor , Temperatura , Resistência à Tração
7.
Int J Biol Macromol ; 111: 604-613, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29325745

RESUMO

The aim of the present work was to study the use of cellulose nanocrystals (CNC) and chitosan nanoparticles (CHNP) for developing controlled-release drug delivery system of the anti-hyperglycemic drug Repaglinide (RPG). CNC was isolated from palm fruit stalks by sulfuric acid hydrolysis; the dimensions of the isolated nanocrystals were 86-237 nm in length and 5-7 nm in width. Simple and economic method was used for the fabrication of controlled release drug delivery system from CNC and CHNP loaded with RPG drug via ionic gelation of chitosan in the presence of CNC and RPG. The prepared systems showed high drug encapsulation efficiency of about ~98%. Chemical modification of CNC by oxidation to introduce carboxylic groups on their surface (OXCNC) was also carried out for further controlling of RPG release. Particles size analysis showed that the average size of CHNP was about 197 nm while CHNP/CNC/RPG or CHNP/OXCNC/RPG nanoparticles showed average size of 215-310 nm. Compatibility studies by Fourier transform infrared (FTIR) spectroscopy showed no chemical reaction between RPG and the system's components used. By studying the drug release kinetic, all the prepared RPG formulations followed Higuchi model, indicating that the drug released by diffusion through the nanoparticles polymeric matrix.


Assuntos
Carbamatos/química , Quitosana/química , Hiperglicemia/tratamento farmacológico , Nanopartículas/química , Piperidinas/química , Carbamatos/uso terapêutico , Celulose/química , Celulose/uso terapêutico , Quitosana/uso terapêutico , Preparações de Ação Retardada/química , Preparações de Ação Retardada/uso terapêutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Hidrólise , Nanocompostos/química , Nanocompostos/uso terapêutico , Nanopartículas/uso terapêutico , Piperidinas/uso terapêutico , Espectroscopia de Infravermelho com Transformada de Fourier
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