Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Exp Mol Pathol ; 125: 104757, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35339454

RESUMO

DNA methylation, as an epigenetic mechanism, occurs by adding a methyl group of cytosines in position 5 by DNA methyltransferases and has essential roles in cellular function, especially in the transcriptional regulation of embryonic and adult stem cells. Hypomethylation and hypermethylation cause either the expression or inhibition of genes, and there is a tight balance between regulating the activation or repression of genes in normal cellular activity. Abnormal methylation is well-known hallmark of cancer development and progression and can switch normal stem cells into cancer stem cells. Cancer Stem Cells (CSCs) are minor populations of tumor cells that exhibit unique properties such as self-regeneration, resistance to chemotherapy, and high ability of metastasis. The purpose of this paper is to show how aberrant DNA methylation accumulation affects self-renewal, differentiation, multidrug-resistant, and metastasis processes in cancer stem cells.


Assuntos
Metilação de DNA , Neoplasias , Adulto , Metilação de DNA/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia
2.
Drug Dev Ind Pharm ; 44(2): 296-305, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29022858

RESUMO

This research study aimed to develop a novel sustained release formulation of alprazolam that can also be used for transdermal delivery. This was carried out, for the first time, through encapsulation of alprazolam in nanoliposomes using ethanol injection. In order to obtain the best formulation, four process variables, including the solvent/nonsolvent volume ratio, phospholipid concentration, alprazolam concentration, and cholesterol content were considered as key factors. Response surface methodology (RSM) and a central composite design (CCD) model were used to investigate the effect of these factors on vesicle size (VS) and encapsulation efficiency (EE) as the major properties of nanoliposomes. Experimental data were statistically analyzed, and two significant quadratic models were developed to test the VS and EE responses. The findings indicate that alprazolam and phospholipid concentrations have a significant effect on the mean VS. However, EE was significantly affected by both the alprazolam and phospholipid concentrations and the cholesterol content. The optimized formulation for preparation of alprazolam-loaded nanoliposomes with appropriate VS and EE was suggested. Small unilamellar vesicles (SUVs), ranging in size from 50 to 100 nm were clearly observed in the transmission electron microscopy (TEM) images, which is appropriate for transdermal delivery of alprazolam. The study of the prepared nanoliposomes over 28 days at 4 °C confirmed the stability of the formulations containing cholesterol. The results of an in vitro release study of alprazolam-loaded nanoliposomes in phosphate buffered saline (PBS), pH 7.4 for 24 h at 37 °C using dialysis, indicated the sustained release of alprazolam due to encapsulation.


Assuntos
Alprazolam/química , Química Farmacêutica/métodos , Lipossomos/química , Nanopartículas/química , Administração Cutânea , Alprazolam/administração & dosagem , Colesterol/química , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Fosfolipídeos/química , Solventes , Propriedades de Superfície
3.
J Microencapsul ; 34(2): 121-131, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28609225

RESUMO

This study suggested successful encapsulation of polyhexamethylene biguanide chloride (PHMB) into nano cationic liposome as a biocompatible antibacterial agent with less cytotoxicity and higher activities. Phosphatidylcholine, cholesterol and stearylamine were used to prepare nano cationic liposome using thin film hydration method along with sonication or homogeniser. Sonication was more effective in PHMB loaded nano cationic liposome preparation with smaller size (34 nm). FTIR, 1H NMR and XRD analyses were used to confirm the encapsulation of PHMB into nano cationic liposome. PHMB inclusion in nano cationic liposome was beneficial for increased antibacterial activity against Staphylococcus aureus and Escherichia coli. PHMB-loaded cationic liposome enables to deliver high concentrations of the antibacterial agent into the infectious cell. The cytotoxicity of PHMB entrapped in positively charged liposome was prominently reduced showing no significant visible detrimental effect on normal primary human skin fibroblast cell lines morphology confirming the effective role of cationic liposome encapsulation. Comparing with PHMB alone, encapsulation of PHMB in nano cationic liposome resulted in significant increase in cell viability from 2.4 to 63%.


Assuntos
Antibacterianos/administração & dosagem , Biguanidas/administração & dosagem , Lipossomos/química , Nanopartículas/química , Linhagem Celular , Escherichia coli/efeitos dos fármacos , Fibroblastos , Humanos , Staphylococcus aureus/efeitos dos fármacos
4.
Pak J Med Sci ; 33(1): 42-47, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28367170

RESUMO

OBJECTIVE: To assess the efficacy of intercostal nerve protection by intercostal muscle (ICM) flap in post-thoracotomy pain improvement compared to intracostal suturing. METHODS: In a randomized controlled trial, ninety-four patients undergoing posterolateral thoracotomy surgery were divided into two subgroups. Intracostal sutures in isolation and in combination with ICM flap techniques were used for thoracotomy closure in both groups. Numeric Pain Scale and Visual Pain Scale as pain scores were assessed on the first, second, third, fourth, fifth, sixth and seventh postoperative days and follow-up visits during the 2nd week, 1st, 2nd, 4th and 6th months after thoracotomy. RESULTS: Out of 94 patients, 58 were male and 36 were females. While the mean age of patients in intracostal group was 45.3 ± 17.6 years, it was 47.4 ± 16.1 years in intracostal plus ICM flap group. The mean operation time for the first group was 191.0 ± 74.7 minutes, while it was 219.3 ± 68.8 minutes in the second (p>0.05). Numeric rating score and visual pain scale did not demonstrate any significant difference in pain severity on postoperative days and follow-up visits between both groups (p>0.05). Although the trend of pain reduction was significant in each group (p<0.001), the difference was not statistically significant (p>0.001). CONCLUSION: Intracostal sutures in combination with muscle flap did not reduce postoperative pain in thoracotomy compared with intracostal sutures alone in thoracotomy closure.

5.
Pak J Med Sci ; 33(5): 1117-1122, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29142549

RESUMO

BACKGROUND & OBJECTIVE: There is no special guideline for the best ventilation mode during laparoscopic anesthesia in obese patients and there are too many studies with different controversial points. The aim of this study was to compare the effect of pressure controlled ventilation (PCV) vs. volume controlled ventilation (VCV) on respiratory and oxygenation parameters in patients undergoing laparoscopic cholecystectomy. METHODS: Seventy patients with 30

6.
J Microencapsul ; 33(6): 497-510, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27701985

RESUMO

Herbal products have been widely used due to good antimicrobial, fragrance and medical properties. Essential oils and fragrances can be applied on the textile substrates as micro/nanocapsules to prolong lifetime by controlling the release rate. The present review tries to give a general overview on the application of micro/nanoencapsulated essential oils on the textile substrates to achieve aromatherapy textiles. These are divided into four diverse categories as the following: antimicrobial, perfumed, mosquito-repellent and medical textiles. The reports in this field revealed that the encapsulation technique plays an important role in the finishing of plant extracts on the textile substrates. It is also anticipated that aromatherapy textiles have to be developed in the new fields such as multifunctional textiles having wound-healing, antimicrobial and fragrant properties.


Assuntos
Anti-Infecciosos/química , Repelentes de Insetos/química , Nanocápsulas/química , Óleos Voláteis/química , Têxteis , Animais , Culicidae
7.
J Liposome Res ; 25(1): 38-45, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24960450

RESUMO

Ag:Au alloy nanoparticles were successfully synthesized through the new route using co-reduction method with silver nitrate, chloroauric acid, cetyl trimethyl ammonium bromide (CTAB) and sodium borohydride at room temperature. The Ag:Au alloy nanoparticles were then loaded within the phosphatidylcholine (97%) liposome structure. Various molar ratios of phosphotidylcholine and CTAB to the total metals were investigated showing its importance on the stability of nanocomposites suspension. The size distribution and morphology of encapsulated nanoparticles within the liposome structure were studied via ultraviolet (UV)-visible spectrum, transmission electron microscope (TEM) micrographs, and dynamic light scattering data. The synthesis of alloy nanoparticles were confirmed with formation of single band at 430, 465 and 500 nm for 75:25, 50:50 and 25:75 Ag:Au mole ratios, respectively. The TEM micrographs of different samples indicated formation of three various nanocomposite structures with size of 82-300 nm. The antibacterial activities of Ag:Au nanocomposites were studied against Pseudomonas aeruginosa through well-diffusion agar. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined by Broth microdilution method. The results showed that 10 ppm nanocomposite reasonably killed the above bacteria.


Assuntos
Antibacterianos/síntese química , Ligas de Ouro/síntese química , Nanocápsulas/química , Fosfatidilcolinas/química , Pseudomonas aeruginosa/efeitos dos fármacos , Prata/química , Antibacterianos/farmacologia , Coloides , Estabilidade de Medicamentos , Ligas de Ouro/farmacologia , Lipossomos , Testes de Sensibilidade Microbiana , Nanocompostos/química
8.
Carbohydr Polym ; 326: 121622, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142078

RESUMO

The textile industry produces 20 % of the industrial water pollution containing toxic substances mostly dyes. Reducing material consumption and developing more efficient and scalable textile waste-water treatment methods such as photocatalytic degradation is essential. In this work, manganese dioxide nanoparticles (MnO2 NPs) were synthesized on the cotton fabric via a facile in-situ process. The preparation process was optimized for the highest photocatalytic activity under sunlight and color change originating from the plasmonic structural color of the nanoparticles. This promotes the photocatalytic activity by delocalization of the hot electrons while demonstrating the best washing and light fastness by using the least chemicals, and energy in a short time. In this way, the fabric was colored without any dye and possessed robust photocatalytic activity. Further, no dye-containing waste-water is made, and also accomplished to degrade dyes in a few hours under sunlight which is substantial for sustainable development. The treated fabrics indicated favorable mechanical properties, enhanced thermal stability, and perfect biocompatibility.

9.
Heliyon ; 10(16): e36522, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39262991

RESUMO

Photocatalysts and noble metals have attracted considerable attention for their potential in addressing global environmental pollution through photochemical processes. At low temperatures, multifunctional self-cleanable wool fabric was developed through green photo-sonosynthesis of N-Ag/TiO2/ZnO. A narrower bandgap of the hybrid photocatalyst, the surface plasmonic resonance effect of silver nanostructures, and nitrogen doping resulted in synergistically enhanced self-cleaning activity. The self-cleaning activity was evaluated by monitoring the discoloration of methylene blue stains on the wool fabric exposed to natural sunlight, using CIELAB color space and ΔE measurements. The ΔE value of the N-Ag/TiO2/ZnO-sonicated wool was superior, showing a value of 45.9 compared to 15.7 for the control and 28.7 for the sample coated by the stirrer. Furthermore, the nanocomposite construction improved tensile strength, enhanced fabric hydrophilicity, and reduced the yellowness index. Additionally, the synthesis of TiO2 and silver particles on ZnO particles increased surface resistance to acid, reducing ZnO acid solubility. The reflectance of the non-treated wool ranged from 5 to 20 % within 200-380 nm, while the reflectance of the Ag/TiO2/ZnO-sonicated sample remained constant at 4 %, exhibiting protection against UV rays. AATCC test revealed 100 % bacteria reduction against E. coli and S. aureus and 99 % against C. albicans fungus for N-Ag/TiO2/ZnO-sonicated sample. Moreover, cell culture assays demonstrated a viability of over 70 %, indicating non-cytotoxicity.

10.
Bioimpacts ; 14(4): 27640, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104619

RESUMO

Introduction: High metastasis, resistance to common treatments, and high mortality rate, has made triple-negative breast cancer (TNBC) to be the most invasive type of breast cancer. High telomerase activity and mitochondrial biogenesis are involved in breast cancer tumorigenesis. The catalytic subunit of telomerase, telomerase reverse transcriptase (hTERT), plays a role in telomere lengthening and extra-biological functions such as gene expression, mitochondria function, and apoptosis. In this study, it has been aimed to evaluate intrinsic-, extrinsic-apoptosis and DNMT3a and TET2 expression following the inhibition of telomerase and mitochondria respiration in TNBC cell lines. Methods: TNBC cells were treated with IC50 levels of BIBR1532, tigecycline, and also their combination. Then, telomere length, and DNMT3a, TET2, and hTERT expression were evaluated. Finally, apoptosis rate, apoptosis-related proteins, and genes were analyzed. Results: The present results showed that IC50 level of telomerase and inhibition of mitochondria respiration induced apoptosis but did not leave any significant effect on telomere length. The results also indicated that telomerase inhibition induced extrinsic-apoptosis in MDA-MB-231 and caused intrinsic- apoptosis in MDA-MB-468 cells. Furthermore, it was found that the expression of p53 decreased and was ineffective in cell apoptosis. The expressions of DNMT3a and TET2 increased in cells. In addition, combination treatment was better than BIBR1532 and tigecycline alone. Conclusion: The inhibition of telomerase and mitochondria respiration caused intrinsic- and extrinsic- apoptosis and increased DNMT3a and TET2 expression and it could be utilized in breast cancer treatment.

11.
Carbohydr Polym ; 302: 120376, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36604054

RESUMO

Here, cellulose was cross-linked with folic acid (FA) using tetrafluoroborate (TBTU) and carbodiimide (DIC) as coupling reagents through the pad method at room temperature. The interactions between FA and cellulose were proposed and determined with FTIR, and UV-visible also confirmed with nitrogen content. The newly formed ester peak showed the grafting of FA to the cellulose through esterification followed by cellulose cross-linking. The surface morphology of treated fabrics indicated no significant changes and also remained similar after 5 washing cycles. This had no negative impacts on the various physical and mechanical fabric features. The fabric color was changed with reasonable fastness to laundering and light. More FA showed higher N content indicating more bacterial killing for Pseudomonas aeroginosa (Psa) and Methicillin-Resistant Staphylococcus (MRSA). The reasonable viability of L929 and MCF-7 cells showed for treated fabric with FA below 5 %.


Assuntos
Celulose , Staphylococcus aureus Resistente à Meticilina , Indicadores e Reagentes , Têxteis
12.
Int J Biol Macromol ; 232: 123292, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-36652983

RESUMO

This research focuses on preparing a natural-based drug delivery system for α-arbutin (AR) as a skin lightening. Bacterial cellulose nanofibers (BC) pad was used for controlled-AR release through two approaches. First was the dip-drying method (P-BC), in which AR cross-linked to BC pads using citric acid (CA). The second was simultaneously entrapping of AR in Tragacanth gum (AR-TG) and stabilized on BC (BC-T) through the ultrasonic-assisted microemulsion method. UV-Vis spectra revealed better control of AR release in BC-T in the first hour. High cell viability (above 70 %) of the pads containing 1-3 % AR was reported using MTT assay. The in-vitro permeation study indicated the proper AR penetration in the treated pads. The Fickian diffusion model was determined as a fitted model for all pads in the drug release kinetics. FTIR, XRD, and TGA analyses further characterized the pads. FESEM images verified AR-TG and BC structures with average diameters of 410.7 ± 25.4 and 34.5 ± 7.51 nm, respectively. The hydrophilicity and mechanical properties of the pads were also investigated. Finally, the high biocompatibility, initial controlled release, and proper permeation suggested BC-T as a more promising delivery platform for AR.


Assuntos
Nanofibras , Tragacanto , Arbutina , Sistemas de Liberação de Medicamentos , Pele
13.
Int J Biol Macromol ; 247: 125576, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37385318

RESUMO

This study explores the potential of using the carbonization of Zn-based metal-organic frameworks (Zn-MOF-5) under N2 and air to modify zinc oxide (ZnO) nanoparticle for the production of various photo and bio-active greyish-black cotton fabrics. The MOF-derived ZnO under N2 demonstrated a significantly higher specific surface area (259 m2g-1) compared to ZnO (12 m2g-1) and MOF-derived ZnO under air (41.6 m2 g-1). The products were characterized using various techniques, including FTIR, XRD, XPS, FE-SEM, TEM, HRTEM, TGA, DLS, and EDS. The tensile strength and dye degradation properties of the treated fabrics were also investigated. The results indicate that the high dye degradation capability of MOF-derived ZnO under N2 is likely due to the lower ZnO band gap energy and improvement in electron-hole pair stability. Additionally, the antibacterial activities of the treated fabrics against Staphylococcus and Pseudomonas aeruginosa were investigated. The cytotoxicity of the fabrics was studied on human fibroblast cell lines using an MTT assay. The study findings demonstrate that the cotton fabric covered with carbonized Zn-MOF under N2 is human-cell compatible while showing high antibacterial activities and stability against washing, highlighting its potential for use in developing functional textiles with enhanced properties.


Assuntos
Óxido de Zinco , Humanos , Óxido de Zinco/farmacologia , Zinco , Têxteis , Antibacterianos/farmacologia , Nitrogênio
14.
Int J Biol Macromol ; 242(Pt 4): 124916, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276903

RESUMO

Zinc oxide nanoparticles (ZnO NPs) have gained significant attention in the textile industry for their ability to enhance the physicochemical properties of fabrics. In recent years, there has been a growing focus on the development of ZnO-based nanomaterials and their applications for cotton and other fabrics. This review paper provides an overview of the synthesis and diverse applications of ZnO-based nanomaterials for textile fabrics, including protection against UV irradiation, bacteria, fungi, microwave, electromagnetic radiation, water, and fire. Furthermore, the study offers the potential of these materials in energy harvesting applications, such as wearable pressure sensors, piezoelectric nanogenerators, supercapacitors, and human energy harvesting. Additionally, we discuss the potential of ZnO-based nanomaterials for environmental cleaning, including water, oil, and solid cleaning. The current research in this area has focused on various materials used to prepare ZnO-based nanocomposites, such as metals/nonmetals, semiconductors, metal oxides, carbon materials, polymers, MXene, metal-organic frameworks, and layered double hydroxides. The findings of this review highlight the potential of ZnO-based nanomaterials to improve the performance of textile fabrics in a range of applications, and the importance of continued research in this field to further advance the development and use of ZnO-based nanomaterials in the textile industry.


Assuntos
Nanopartículas , Óxido de Zinco , Humanos , Óxido de Zinco/química , Têxteis , Nanopartículas/química , Água
15.
Iran J Med Sci ; 48(5): 465-473, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37786464

RESUMO

Background: Plasma total cholesterol is considered a negative acute phase reactant. In various pathological conditions, such as trauma, sepsis, burns, and liver dysfunction, as well as post-surgery, serum cholesterol level decreases. This study aimed to investigate the role of lipid profiles in determining the probability of organ dysfunction after surgery. Methods: This cross-sectional study included patients who underwent thoracoabdominal surgery and were admitted to the intensive care unit of Imam Reza Hospital in Tabriz, Iran, between October 2016 and September 2018. During the first two days of admission, blood samples were taken, and serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), Low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and albumin were measured. The relation between the changes in these laboratory markers and six organ functions including cardiovascular, respiratory, renal, central nervous system, hepatic, and hematologic, length of stay in the hospital and intensive care unit, mechanical ventilation duration, and vasopressor use were investigated. The independent t test was used to compare continuous variables. The association between different variables and organ dysfunction and mortality was evaluated by using logistic regression. Results: The serum TC increased the risk of mortality (OR=1.09, 95%CI=1.06-1.11, P<0.001), renal dysfunction (OR=1.09, 95%CI=1.06-1.12; P<0.001), liver dysfunction (OR=1.07, 95%CI=1.03-1.10; P<0.001), respiratory dysfunction (OR=1.08, 95%CI=1.05-1.13; P<0.001). Moreover, LDL, HDL, and TG were found to be inversely related to mortality, organ dysfunction, length of stay in the hospital and intensive care unit, mechanical ventilation duration, and vasopressor use. Conclusion: TC could be considered a risk factor for mortality, organ dysfunction, and clinical outcomes. On the other hand, LDL, HDL, and TG played a protective role in the patients' mortality, organ dysfunction, and clinical outcomes.


Assuntos
Insuficiência de Múltiplos Órgãos , Humanos , Estudos Transversais , Insuficiência de Múltiplos Órgãos/epidemiologia , Insuficiência de Múltiplos Órgãos/etiologia , Triglicerídeos , HDL-Colesterol , LDL-Colesterol
16.
Ann Med Surg (Lond) ; 85(6): 2781-2786, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37363555

RESUMO

Chylothorax is a crucial postoperative complication of esophagectomy. Characterized by the leakage of chyle and lymphatic fluid through the thoracic duct, chylothorax could result in pleural effusion, respiratory distress, shortness of breath, cardiac arrhythmia, electrolyte imbalance, and malnutrition. Postesophagectomy chylothorax is associated with high morbidity and mortality, and its diagnosis and management require prompt and accurate identification of risk factors and treatment strategies. A variety of strategies are available to treat postesophagectomy chylothorax, ranging from conservative management to pharmacological, lymphangiographic, and surgical treatments. This study reviews the physio-anatomical basis, disease presentation, diagnostic methods, risk factors, and management options for postesophageal chylothorax, filling the literature gap, and highlighting the importance of early recognition and timely intervention in improving patient outcomes.

17.
Chem Biol Drug Des ; 101(5): 1151-1161, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35993390

RESUMO

LncRNAs and miRNAs are the two most important non-coding RNAs, which have been identified to be associated with cancer progression or prevention. The dysregulation of lncRNAs conducts tumorigenesis and metastasis in different ways. One of the mechanisms is that lncRNAs interact with miRNAs to regulate distinct cellular and genomic processes and cancer progression. LncRNA SNHG7 as an oncogene sponges miRNAs and develops lncRNA-miRNA-mRNA axes, leading to the regulation of several signaling pathways such as Wnt/ß-Catenin, PI3K/AKT/mTOR, SIRT1, and Snail-EMT. Therefore, in this article, after a brief overview of lncRNA SNHG7-miRNA-mRNA axes' contribution to cancer development, we will discuss the role of lncRNA SNHG7 in the genes expression and signaling pathways related to cancers development via acting as a ceRNA.


Assuntos
MicroRNAs , Neoplasias , RNA Longo não Codificante , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes
18.
Mol Membr Biol ; 28(4): 206-15, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21428718

RESUMO

The antimicrobial property of stabilized silver nanoparticles (AgNPs) with phospholipid membrane was investigated on both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial strains. The influence of phospholipid concentrations on antibacterial kinetics actions of AgNPs was studied with two different methodologies in order to understand the bactericidal and bacteriostatic effects. The bacterial inactivation of synthesized AgNPs fitted well to the Chick-Watson model with a high regression coefficient, R(2) > 0.91. The antibacterial properties of AgNPs depend on the particle size, stabilizer and lecithin concentrations. Only the stabilized AgNPs that have the K(lec/Ag) values of 1 and 2 presented the inhabitation zone, while unstabilized AgNPs agglomerated quickly, settled on the wells and did not diffuse in agar. In addition, the specific coefficient of lethality depends on the lecithin concentration. An increase in lecithin concentration caused multilayer creation on the AgNPs' surface and reduced the release of AgNPs which led to low bacterial killing rate.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Fosfolipídeos/química , Prata/química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos
19.
Carbohydr Polym ; 275: 118584, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742403

RESUMO

Here, Cotton fabric was functionalized via hybrid coating including 2D MgAl LDH (layered double hydroxide) and SA (stearic acid). The urea hydrolysis was employed for construction of vertically aligned LDH on surface of cellulose fibers under hydrothermal condition. The in situ formation mechanism of LDH on cotton surface was nucleation, growth, and interaction with activated cellulose chains. The partial cellulose ionization in the alkaline solution led to nucleophilic behavior towards electron deficient atom. The effect of different ageing, synthesis temperature, and amount of SA were investigated and optimized at 100 °C for 24 h with 0.05 M. The superhydrophobic surface architecture of treated cotton with hierarchical micro/nanostructure was inspired from the Taro leaf structure with continuous contact line presented WCA of 154 ° and CAH of 9 °. The Cotton@LDH@SA exhibited efficient oil/water separation after several washes (>90%) with good stain resistant. Also, the physico-mechanical properties were studied.


Assuntos
Celulose/química , Colocasia/química , Fibra de Algodão , Hidróxidos/química , Ureia/química , Alumínio/química , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Magnésio/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ácidos Esteáricos/química , Têxteis , Molhabilidade , Difração de Raios X/métodos
20.
Int J Biol Macromol ; 219: 637-649, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-35914556

RESUMO

The amino-functionalized cellulose with folic acid, via an esterification reaction between carboxylic acid of folic acid and hydroxyl groups of cellulose, can develop multifunctional products with new chemical and physical properties. Folic acid contains two carboxylic groups as well as an amine group that can be used as a coupling agent and provide suitable conditions for coupling hydroxyl-based compounds to cellulose. Also; the multi-functionalized cellulose with folic acid has no effects on the physical and mechanical properties and also has benefits such as antibacterial, UV protection, and wrinkle resistance. The FTIR-ATR and Raman analysis confirmed the amino functionalized-cellulosic fabric via an esterification reaction between cellulose and folic acid. The cell viability of L929 fibroblast (NCBI C161) and MCF-7 (NCBI C135) cancer cells indicated more effectiveness on MCF-7 cancer cells. Therefore; folic acid can be used as a biocompatible natural cross-linker to modify cellulose fabrics for apparel and medical applications.


Assuntos
Antibacterianos , Ácido Fólico , Aminas , Antibacterianos/química , Antibacterianos/farmacologia , Ácidos Carboxílicos , Celulose/química , Celulose/farmacologia , Ácido Fólico/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA