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1.
Environ Sci Pollut Res Int ; 31(9): 13185-13206, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38240971

RESUMO

To effectively remove pharmaceuticals, nitroaromatic compounds, and dyes from wastewater, an efficient multifunctional material was created based on silver nanoparticles (Ag) and MIL-125-NH2 (MOF) immobilized on viscose fibers (VF) as a support substrate. Firstly, silver nanoparticles (Ag) were immobilized on the surface of viscose fibers (VF) via in situ synthesis using trisodium citrate (TSC) as a reducing agent to create (VF-Ag). Then, VF and VF-Ag were decorated with the titanium metal-organic framework MIL-125-NH2 (MOF) to create VF-MOF and VF-Ag-MOF. The influence of VF-Ag, VF-MOF, and VF-Ag-MOF on the sonocatalytic or sonophotocatalytic degradation of sulfa drugs was investigated. The results show that VF-Ag-MOF showed excellent sonocatalytic and sonophotocatalytic activity towards the degradation of sulfa drugs compared to VF-Ag and VF-MOF. Furthermore, sonophotodegradation showed a dramatic enhancement in the efficiency of degradation of sulfa drugs compared to sonodegradation. The sonophotodegradation degradation percentage of sulfanilamide, sulfadiazine, and sulfamethazine drugs in the presence of VF-Ag-MOF was 65, 90, and 95 after 45 min of ultrasonic and visible light irradiation. The catalytic activity of VF-Ag, VF-MOF, and VF-Ag-MOF was evaluated through the conversion of p-nitrophenol (4-NP) to p-aminophenol (4-AP). The results demonstrate that VF-Ag-MOF had the highest catalytic activity, followed by VF-Ag and VF-MOF. The conversion percentage of 4-NP to 4-AP was 69%. The catalytic or photocatalytic effects of VF-Ag, VF-MOF, and VF-Ag-MOF on the elimination of methylene blue (MB) dye were investigated. The results demonstrate that VF-Ag-MOF showed high efficiency in removing the MB dye through the reduction (65%) or photodegradation (71%) after 60 min. VF-Ag-MOF composites structure-activity relationships represent that doping within silver NPs enhanced the photocatalytic activity of MIL-125-NH2, which could be explained as follows: (i) Due to the formation of a Schottky barrier at the junction between MIL-125-NH2 and Ag NPs, the photogenerated electrons in the conduction band of MIL-125-NH2 were supposed to be quickly transferred to the valence band of the Ag NPs, and subsequently, the electrons were transferred to the conduction band of Ag NPs. This considerable electron transferring process, which is reported as Z scheme heterojunction, can efficiently suppress the recombination of electron/hole pairs in VF-Ag-MIL-125-NH2 composites. (ii) Sufficient separation between the photogenerated charge carriers (holes and electrons) and avoiding their recombination enhanced the photocatalytic activity of composites.


Assuntos
Nanopartículas Metálicas , Prata , Prata/química , Nanopartículas Metálicas/química , Titânio/química , Luz , Fotólise
2.
Prz Menopauzalny ; 22(3): 121-125, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37829269

RESUMO

Introduction: The goal of this study is to evaluate the effectiveness of single-incision mini-sling in the surgical treatment of postmenopausal urodynamic stress urinary incontinence (SUI) compared to the standard trans-obturator mid-urethral sling. Material and methods: This prospective study was carried out in two tertiary centres; Al-Azhar University Maternity & Urology Hospitals. A total of 120 postmenopausal women with urodynamic SUI were randomized to undergo either single-incision mini-sling (n = 60) or standard trans-obturator mid-urethral sling procedure (n = 60) from May 2019 until Oct 2021. Main outcome measures: efficacy was evaluated utilizing objective cure rate (cough stress test) and subjective cure rate (Sandvik incontinence severity index and International Consultations on Incontinence Questionnaire - Short Form), intraoperative and postoperative complications, and postoperative pain (using a visual analogue scale). Results: The single-incision mini-sling (SIMS) and transobturator tape (TOT) groups had no statistically significant difference in subjective and objective cure rates (p > 0.05). Compared with the transvaginal tape O group, patients in the SIMS group had significantly less postoperative pain, shorter operative duration, and less intraoperative blood loss (all p-values < 0.05). No significant difference in perioperative complications was observed between both groups. Conclusions: Single-incision mini-sling was superior to TOT in postmenopausal as SIMS is of similar effectiveness, more safe and minimally invasive with earlier ambulance.

3.
Adv Urol ; 2022: 6996933, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187436

RESUMO

Background: Proximal hypospadias, with significant curvature, is one of the most challenging anomalies. Great diversity and a large number of procedures described over the last 4 decades confirmed the fact that no single procedure has been universally accepted or successful. So, the aim of this study is to evaluate double-faced tubularized preputial flap (DFPF) versus transverse tubularized inner preputial flap (Duckett's procedure) as regards surgical outcomes, complications rate, and cosmetic results for repair of penoscrotal hypospadias with chordee. Patients and Methods. This was a prospective comparative study on 144 children with primary penoscrotal hypospadias with moderate or severe chordee, conducted at New Damietta and Assuit hospitals, Al-Azhar University, from March 2016 to March 2022. The patients were randomly divided into two equal groups; group A (n = 72) underwent DFPF, and group B (n = 72) underwent Duckett's procedure. Results: No significant difference was identified as regards demographic data. The follow-up period ranged from 20 to 66 months (mean of 28 months after DFPF and 31 months after Duckett's repair), and the complication rate was 20.1% (29 of 144 children). There were statistically significant differences between the two groups as regards the urethral stricture, penile rotation, and total complication rate. HOSE score was adopted for assessment of surgical outcomes, urine stream, and cosmetic results. Conclusions: The DFPF technique is feasible and reliable for one-stage repair of penoscrotal hypospadias with chordee and can be considered as a good option as it ensures better surgical and cosmetic outcomes with lower incidence of complications.

4.
Medicine (Baltimore) ; 101(35): e30235, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36107538

RESUMO

INTRODUCTION: The classical way to treat urethral stricture is the direct vision cold knife internal urethrotomy (DVIU). Along with advances in laser technology, laser urethrotomy is widely used, such as neodymium-doped yttrium aluminum garnet, argon, potassium titanyl phosphate, and thulium laser. We aimed to compare thulium laser urethrotomy (TLU) and cold knife visual urethrotomy (CKVU) in terms of short bulbomembranous urethral stricture management. MATERIALS AND METHODS: This prospective interventional study was conducted for 24 months, from January 2018 to January 2020, on 60 patients with primary short bulbo-membranous urethral stricture who came to the Department of Urology of Al-Azhar University Hospital, New Damietta, Egypt. We divided these patients into 2 age-matched groups; 30 patients treated with CKVU and 30 patients with TLU. RESULTS: Regarding efficacy, postvoid residual urine volume (PVR) was reduced significantly in both groups (P < .001) after 6 months of follow-up; however, the reduction in TLU was greater than CKVU (P = .008). The improvement of Qmax after 6 months was significant and comparable in both groups. Regarding the quality of life, both groups showed a significant (<0.05) improvement in international prostate symptom score (IPSS) and the Male Sexual Health Questionnaire (MSHQ) scale, without no significant difference between both groups (>0.05). TLU showed a significantly (P = .038) shorter operative duration (24 ± 4.17 min) than CKVU duration (33 ± 4.86 min). Compared with CKVU, TLU was associated with less blood loss during surgery (P = .001), lower recurrence rate (46.7% vs. 19.97%, respectively), and lower frequencies of urethral dilatation (P = .001). CONCLUSION: TLU is an effective and safe therapy for managing bulbomembranous urethral strictures, with a relatively low recurrence rate. Further investigations of other techniques are recommended to look for the most appropriate procedure to combat the urethral stricture problem.


Assuntos
Estreitamento Uretral , Alumínio , Argônio , Humanos , Lasers , Masculino , Neodímio , Estudos Prospectivos , Qualidade de Vida , Túlio/uso terapêutico , Resultado do Tratamento , Estreitamento Uretral/cirurgia , Ítrio
5.
Nanomaterials (Basel) ; 11(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567743

RESUMO

Medical textiles have played an increasingly important protection role in the healthcare industry. This study was aimed at improving the conventional cotton gauze for achieving advanced biomedical specifications (coloration, UV-protection, anti-inflammation, and antimicrobial activities). These features were obtained by modifying the cotton gauze fabrics via in-situ precipitation of hydroxyapatite nanoparticles (HAp NP), followed by in-situ photosynthesis of silver (Ag) NPs with ginger oil as a green reductant with anti-inflammation properties. The HAp-Ag NPs coating provides good UV-protection properties. To further improve the HAp and Ag NPs dispersion and adhesion on the surface, the cotton gauze fabrics were modified by cationization with chitosan, or by partial carboxymethylation (anionic modification). The influence of the cationic and anionic modifications and HAp and Ag NPs deposition on the cotton gauze properties (coloration, UV-protection, antimicrobial activities, and water absorption) was thoroughly assessed. Overall, the results indicate that chemical (anionic and cationic) modification of the cotton gauze enhances HAp and Ag NPs deposition. Chitosan can increase biocompatibility and promotes wound healing properties of cotton gauze. Ag NP deposition onto cotton gauze fabrics brought high antimicrobial activities against Candida albicans, Gram-positive and Gram-negative bacteria, and improved UV protection.

6.
Carbohydr Polym ; 244: 116479, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32536384

RESUMO

Herein, a novel burn wound healing material was developed by new strategy. This strategy involved two steps. In the first step, the cotton gauze fabrics were modified with Quat 188 as cationizing agent. After that, the cationized cotton gauze fabrics were developed via in-situ incorporating of silver nanoparticles (Ag NPs) and then loaded with oxytetracyline hydrochloride drug to produce the cationized cotton gauze fabrics/Ag NPs/drug (S1). In the second step, chitosan (CS) was reacted with different amount of salicylaldehyde (SA) via Schiff base reaction to produce salicyl-imine-chitosan biopolymer. Then, the salicyl-imine-chitosan biopolymer was coated onto S1. The functional properties of modified cotton gauze fabrics, including the swelling rate capacity %, dehydration rate %, and antimicrobial as well as burn wound healing properties were evaluated. The overall results suggest that, the modified cotton gauze fabrics can be utilized in biomedical textiles as antimicrobial and burn wound healing properties.


Assuntos
Bandagens , Queimaduras/tratamento farmacológico , Fibra de Algodão , Nanopartículas Metálicas/uso terapêutico , Oxitetraciclina , Prata/uso terapêutico , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Quitosana/química , Feminino , Oxitetraciclina/uso terapêutico , Ratos
7.
Carbohydr Polym ; 231: 115740, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888855

RESUMO

Colorimetric nanocomposite film sensor was fabricated by incorporating TCFH spectroscopic probe into cellulose nanowhiskers (CNW)/Urease enzyme matrix. CNW-TCFH can be used as disposable molecular biosensor in which CNW is the probe carrier comprising high surface area-to-volume ratio, urease is the catalyst and TCFH is the molecular probe. Tricyanofuran-hydrazone (TCFH) spectroscopic probe was prepared. UV-vis absorption spectra demonstrated solvatochromic behavior and a reversible color change of the tricyanofuran-hydrazone probe solution in acetone under acid/base conditions. CNW were reinforced with sodium alginate biopolymer to introduce biocomposite film. This CNW-TCFH film biosensor responds through visible color shift from light yellow to pink when exposed to urea in aqueous media. The morphology properties of CNW and CNW-TCFH films were examined by different tools. The photophysical properties of the prepared TCFH probe, including solvatochromism and pH sensory, were also studied.

8.
Environ Sci Pollut Res Int ; 27(4): 3803-3818, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31838699

RESUMO

Color is a major attraction component of any fabric regardless of how admirable its constitution. Industrial production and utilization of synthetic dyestuffs for textile dyeing have consequently become a gigantic industry today. Synthetic dyestuffs have introduced a broad range of colorfastness and bright hues. Nonetheless, their toxic character has become a reason of serious concern to the environment. Usage of synthetic dyestuffs has adverse impacts on all forms of life. Existence of naphthol, vat dyestuffs, nitrates, acetic acid, soaping chemicals, enzymatic substrates, chromium-based materials, and heavy metals as well as other dyeing auxiliaries, makes the textile dyeing water effluent extremely toxic. Other hazardous chemicals include formaldehyde-based color fixing auxiliaries, chlorine-based stain removers, hydrocarbon-based softeners, and other non-biodegradable dyeing auxiliaries. The colloidal material existing alongside commercial colorants and oily froth raises the turbidity resulting in bad appearance and unpleasant odor of water. Furthermore, such turbidity will block the diffusion of sunlight required for the process of photosynthesis which in turn is interfering with marine life. This effluent may also result in clogging the pores of the soil leading to loss of soil productivity. Therefore, it has been critical for innovations, environmentally friendly remediation technologies, and alternative eco-systems to be explored for textile dyeing industry. Different eco-systems have been explored such as biocolors, natural mordants, and supercritical carbon-dioxide assisted waterless dyeing. Herein, we explore the different types of dyeing processes, water consumption, pollution, treatment, and exploration of eco-systems in textile dyeing industry.


Assuntos
Corantes/química , Resíduos Industriais , Indústria Têxtil , Corantes/análise , Meio Ambiente , Resíduos Industriais/análise , Têxteis
9.
Int J Biol Macromol ; 141: 1022-1034, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31487517

RESUMO

This current study aims to study of the thermal behavior of the polyurethane elastomers (PUEs) by varying blends of 1, 4-butanediol and chitosan (CS) into the backbone of polyurethane (PU). The polycaprolactone diol (PCL) was used as a macrodiol while a mixture of CS and 1, 4-butanediol was reacted to extend the polymer. For the preparation of NCO-endcapped polyurethane prepolymer; one equivalent of PCL was reacted with three equivalents of toluene diisocyanate (TDI). The obtained pre-polymer was further extended with CS and 1, 4-butanediol (2 mol) individually and with different blends. The characterization of the structure was determined using FTIR and NMR spectroscopy. The glass transition temperature of prepared polyurethanes was measured by differential scanning calorimetry (DSC). The results obtained showed that, the thermal behavior of PUs was enhanced as the CS contents were increased in the PU backbone. The crystalline behavior of CS increased the hydrophobicity of the prepared PUs. Moreover; the water absorption, contact angle, swelling behavior, work of water adhesion and surface free energy of the synthesized PUs were affected with the addition of chitosan. Finally, it has been concluded resultant chitosan based PU has a potential for biomedical implant i.e., non-absorbable suture.


Assuntos
Butileno Glicóis/química , Quitosana/química , Poliésteres/química , Poliuretanos/química , Temperatura , Propriedades de Superfície
10.
Int J Biol Macromol ; 124: 1016-1024, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30500494

RESUMO

Skin re-infection problems and its correlation with inflammation, causes rising wound temperature resulting wound healing impairment. In this current study, polyvinyl alcohol (PVA) hydrogel blended with thermosensitive sodium alginate-g-N-isopropyl acrylamide (SA-g-NIPAM) producing thermosensitive hydrogel (PVA/SA-g-NIPAM) for controlled response to re-infected wounds. The thermosensitive SA-g-NIPAM was prepared using redox copolymerization with NIPAM. The fabricated (PVA/SA-g-NIPAM) grafted copolymer was investigated via FTIR technique. The physical properties (swelling ratios) and the morphological structure of the formed PVA/SA-g-NIPAM blend (50/50) were examined. The prepared hydrogel of PVA/SA-g-NIPAM immobilized with anti-inflammatory drug; diclofenac sodium (DS) was assessed via studying the in-vitro release of DS at acidic and neutral pH (5.5 and 7) respectively. The results obtained indicated that the swelling behavior of hydrogel strongly effected with modification process applied onto SA in addition to the carboxylic groups of SA which showed a positive effect on the physical properties at neutral and basic medium. Furthermore, studying the in-vitro release of DS loaded PVA/SA-g-NIPAM in correlation with temperature indicated that 65% of DS at room temperature and 35% at over body temperature were released. On the other hand, the DS loaded PVA/SA hydrogel was completely released within the first 60 min. The obtained results considered to supply the medical field with new pH-thermosensitive hydrogel can face re-infection skin wounds troubles.


Assuntos
Resinas Acrílicas , Alginatos , Hidrogéis , Álcool de Polivinil , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico , Resinas Acrílicas/química , Resinas Acrílicas/farmacologia , Alginatos/química , Alginatos/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Temperatura Alta , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Concentração de Íons de Hidrogênio , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia
11.
Environ Sci Pollut Res Int ; 25(29): 29054-29069, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30109691

RESUMO

In this manuscript, we report the simple method to multifunctional wool fiber surfaces. The multifunctional wool fibers were devised with brilliant coloration, antimicrobial activity, and UV-protection property. These multifunctional properties were progressed by in situ assemble of silver nanoparticles (Ag NPs) into the wool fiber surface using green cleaner one-pot route. The proteins existing in the wool fibers acted being a redox active bio-template, facilitating the reduction of Ag+ to Ag0, with simultaneous binding of the produced Ag NPs both on the surface and within the center of the wool fibers. The entire results showed that the Ag NP in situ-incorporated wool fibers can be used as colorant wool fibers effectively, and these colored fibers also exhibit an improvement for multi-functionality properties.


Assuntos
Anti-Infecciosos/farmacologia , Nanopartículas Metálicas/química , Prata/química , Fibra de Lã , Animais , Anti-Infecciosos/química , Cor , Escherichia coli/efeitos dos fármacos , Micro-Ondas , Espectroscopia Fotoeletrônica , Protetores contra Radiação/química , Protetores contra Radiação/farmacologia , Prata/metabolismo , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta
12.
Carbohydr Polym ; 197: 227-236, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30007608

RESUMO

In situ synthesis of Ag/AgX nanoparticles (NPs) onto viscose fibers adds new functionalities and broadens their applications. In this study, Ag/AgX (X = Cl, I) NPs were in situ synthesized onto viscose fibers to impart brilliant colors, UV-protection, antimicrobial, self-cleaning, and photocatalytic properties. The AgX NPs were deposited on the fibers by ultrasonic irradiation, while Ag-NPs were formed by photoreduction of excess Ag+ ions under UV irradiation. The Ag/AgX NPs-loaded onto viscose fibers endowed with pale yellow for Ag/AgI and pale purple/violet for Ag/AgCl. The colored viscose fibers showed excellent antimicrobial activity against Escherichia coli (gram-negative), Staphylococcus aureus (Gram positive), and Candida Albican. The Ag/AgX/viscose fiber also showed excellent photocatalytic and self-cleaning activity toward degradation of methylene blue.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Iodetos/química , Iodetos/farmacologia , Testes de Sensibilidade Microbiana , Nanopartículas/química , Prata/química , Prata/farmacologia , Compostos de Prata/química , Compostos de Prata/farmacologia
13.
Carbohydr Polym ; 195: 143-152, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29804962

RESUMO

Smart clothing can be defined as textiles that respond to a certain stimulus accompanied by a change in their properties. A specific class herein is the photochromic and fluorescent textiles that change color with light. A photochromic and fluorescent cotton fabric based on pigment printing is obtained. Such fabric is prepared by aqueous-based pigment-binder printing formulation containing inorganic pigment phosphor characterized by good photo- and thermal stability. It exhibits optimal excitation wavelength (365 nm) results in color and fluorescence change of the fabric surface. To prepare the transparent pigment-binder composite film, the phosphor pigment must be well-dispersed via physical immobilization without their aggregation. The pigment-binder paste is applied successfully onto cotton fabric using screen printing technique followed by thermal fixation. After screen-printing, a homogenous photochromic film is assembled on a cotton substrate surface, which represents substantial greenish-yellow color development as indicated by CIE Lab color space measurements under ultraviolet light, even at a pigment concentration of 0.08 wt% of the printing paste. The photochromic cotton fabric exhibit three excitation peaks at 272, 325 and 365 nm and three emission peaks at 418, 495 and 520 nm. The fluorescent optical microscope, scanning electron microscope, elemental mapping, energy dispersive X-ray spectroscopy, fluorescence emission and UV/Vis absorption spectroscopic data of the printed cotton fabric are described. The printed fabric showed a reversible and rapid photochromic response during ultra-violet excitation without fatigue. The fastness properties including washing, crocking, perspiration, sublimation/heat, and light are described.

14.
Carbohydr Polym ; 195: 460-467, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29805000

RESUMO

Hemodialysis is one of the earliest artificial kidney systems, which removes uremic toxins through using a semipermeable porous membrane. Current report focuses on designation of metal organic framework (MOF) based zirconium@cotton fabric composite and its application in kidney dialysis. UiO-66-(COOH)2 as MOF material was directly grown within cotton fabric. Fabric was firstly reacted with benzene tetra carboxylic acid forming ester and then Zr was interacted with the free carboxylic groups in the formed ester to produce UiO-66-(COOH)2@cotton fabric composite. The obtained composite was characterized by using electron microscope, X-ray diffraction, infrared spectroscopy and colorimetric data. After modification with MOF, fabric was acquired yellowish color. The prepared composite was used in potential kidney application through studying the removal of creatinine from mimic blood. The maximum adsorption capacity of creatinine was 113.6 and 192.3-212.8 mg/g for pristine fabric and UiO-66-(COOH)2@fabric composite, respectively. From adsorption data, creatinine adsorption onto composite was followed to pseudo-second order kinetic model and Langmuir isotherm profile. After three regeneration cycles, the applied composite still achieved substantial adsorption capacity by removing of 82% from creatinine. UiO-66-(COOH)2@cotton could be considered as successful adsorbent capable of removing creatinine from blood with good reusability, which can be applied in kidney dialysis.


Assuntos
Fibra de Algodão , Membranas Artificiais , Compostos Organometálicos/química , Diálise Renal/instrumentação , Zircônio/química , Adsorção , Creatinina/química , Diálise Renal/métodos
15.
Carbohydr Polym ; 186: 310-320, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29455992

RESUMO

The current approach focuses on studying the leverage of nanosilver (AgNPs) incorporation on the dyeing process of viscose fibers by blue reactive dye. Nanosilver was straightway incorporated into viscose fibers using sodium citrate as nanogenerator. Owing to AgNPs incorporation, color of fibers was turned to greenish-blue and darker greenish color was observed with low Ag content (<1 g/kg). Regardless to the processes sequencing, color strength of fibers was magnified by increasing in Ag content. The constancy of fibers color was not affected by AgNPs inclusion, whatever the processes sequencing and Ag content. Release property of Ag from fibers into water was considerably depended on the processes sequencing. By incorporation of AgNPs firstly, the lowest Ag release value was estimated (0.25 g/kg after 24 h). Antimicrobial activities were significantly improved by AgNPs incorporation. Reduction in bacteria and fungi was reached 92.4% and 67.9% after 24 h contact time, respectively.


Assuntos
Antibacterianos/química , Antifúngicos/química , Celulose/química , Nanopartículas Metálicas/química , Prata/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos
16.
Carbohydr Polym ; 182: 29-41, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29279123

RESUMO

The present work addresses an innovative approach for benign development of environmentally synthesis of chitosan-based nanocomposite. The synthesis involves the inclusion via interaction of AgNPs and clay with chitosan (Cs) giving rise to Cs/AgNPs and Cs/AgNPs/clay nanocomposites which when applied independently induce super functionalities. Comparison is made among the two nanocomposites with respect to their intimate association with the in depth cotton fibre-fabric surfaces and the onset of this on the multi-functionalization of cotton fabrics. It is as well to emphasize that Cs/AgNPs/clay nanocomposites prove unequivocally that its use in one-step treatment process for cotton fabrics results in imparting very appreciable good technical properties which, in turn, are reflected on all the gained functionalities of cotton fabrics. Of these functional performance properties, mention is made of cotton fabrics which exhibit high strength, uniform morphology, increased thermal stability, successful deposition of the composite on the surface of cotton fabrics, high water absorption, antimicrobial activity, flame retardant, controlled release of fragrance and UV protection. The obtained data indicate that the treatment for cotton fabrics with these nanocomposite is stable against washing even after 20 washing cycles. Based on encourage data, the environmental benign synthesis of Cs/AgNPs/clay nanocomposites is considered as a promising nanocomposite for the multifunctional finishing textiles.


Assuntos
Silicatos de Alumínio/química , Quitosana/química , Fibra de Algodão , Nanocompostos/química , Prata/química , Argila
17.
Mater Sci Eng C Mater Biol Appl ; 80: 29-37, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28866167

RESUMO

The ideal biomedical fiber/fabric materials can both promote the drug delivery properties and prevent microbial infection. Herein we present an innovation-based strategy for fabrication of biomedical cotton gauze which concomitantly displays antimicrobial and drug delivery performance properties. The innovative strategy involved three distinct steps: (1) Cationization of cotton gauze by reacting it with 3-chloro-2-hydroxypropyl trimethyl ammonium chloride [Quat-188] or anionization of cotton gauze through partial carboxymethylation. (2) Thus modified samples of cotton gauze along with unmodified blank samples were submitted to in situ formation of silver nanoparticles (AgNPs) using trisodium citrate (TSC) which has three-fold functions: (a) reducing agent for conversion of Ag+ to Ago (atom), (b) stabilizing agent to prevent aggregation of AgNPs and, (c) linker for fixation of AgNPs on the surfaces of the cotton gauze. (3) All the modified and unmodified cotton gauze samples were loaded with oxytetracyline hydrochloride drug. To this end, characterization of the modified and unmodified cotton samples before and after being loaded with drug using state-of-the-art facilities was undertaken. These facilities comprised UV-vis spectroscopy, energy dispersive X-ray, scanning electron microscope and Infrared Spectroscopy by Attenuated total Reflectance (ATR/IR). Evaluation of the antimicrobial and drug release properties of the cotton gauze samples in question was conducting. Results obtained signified that the modified cotton gauze can be used in the area of biomedical textiles particularly as antimicrobial and drug delivery. Also reported were mechanisms entailed in chemical modifications of cotton gauze and interactions of this modified cotton gauze with antimicrobial as well as with drugs.


Assuntos
Fibra de Algodão , Anti-Infecciosos , Nanopartículas Metálicas , Prata , Têxteis
18.
Int J Biol Macromol ; 98: 877-886, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28215565

RESUMO

Herein, the highly multifunctional cotton fabric surfaces were designed with excellent coloration, UV-protection function, and antimicrobial activity. These multifunctional functions were developed by in-situ synthesis of silver nanoparticles (Ag NPs) into the cotton fabric surface using a simple green one-pot "UV-reduction" method. Cotton fabrics were pretreated with non-anionic detergent, immersed into alcoholic silver nitrate solution (concentration ranging from 100 to 500ppm), squeezed to remove excess solution and then exposed to UV-irradiation (range 320-400nm) for 1h. The influence UV-irradiation on the thermal, chemical, optical and biological properties of the cotton fabric surface was discussed in details. The UV-irradiation promotes reducing of Ag+ ions and the cotton fabrics act as seed medium for Ag NPs formation by "heterogeneous nucleation". Increasing Ag+ concentration (from 100 to 500ppm) results in Ag NPs of particle size (distribution) of 50-100nm. Interestingly, the Ag NPs exhibited different localized surface Plasmon resonance properties causing a coloration of the cotton fabrics with different color shades ranging from bright to dark brown with excellent color fastness properties. The treated cotton fabrics also show high protecting functions against UV-transmission (reduction of 65%) and Escherichia coli growth (99%). The side-effects of the UV-reduction process are further investigated.


Assuntos
Celulose/química , Nanopartículas Metálicas/química , Têxteis , Celulose/síntese química , Celulose/farmacologia , Celulose/efeitos da radiação , Fibra de Algodão , Escherichia coli/efeitos dos fármacos , Tamanho da Partícula , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Raios Ultravioleta
19.
ACS Appl Mater Interfaces ; 8(16): 10551-61, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27025589

RESUMO

Controlling the size and shape of noble Ag nanocrystals (NCs) is of great interest because of their unique size- and shape-dependent properties, especially below 20 nm, and because of interesting applications in drug delivery, sensing, and catalysis. However, the high surface energy and tendency of these tiny NCs to aggregate deteriorates their unique properties and limits their applications. To avoid the aggregation of Ag NCs and improve their performance, we report a seed-mediated hot injection approach to synthesize highly dispersed tiny Ag NCs on a nanosized solid CaCO3 support. This simple, low-cost, and effective chemical approach allows for synthesizing highly uniform Ag NCs (∼10 nm) on the surface of presynthesized CaCO3 single NCs (∼52 nm) without any aggregation of the Ag NCs. Viscose fibers were coated with the Ag@CaCO3 composite nanoparticles (NPs) produced, as well as with ∼126 nm Ag NPs for reference. The Ag@CaCO3 composite NPs show excellent UV protection and antibacterial activity against Escherichia coli. In addition, they give a satin sheen gold to a dark gold color to the viscose fibers, while the Ag NPs (∼126 nm) result in a silver color. The proposed synthesis approach is highly versatile and applicable for many other noble metals, like Au or Pt.

20.
J Parasitol ; 102(1): 69-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26509291

RESUMO

Giardia duodenalis is considered the most common intestinal parasite in humans worldwide. Children are especially affected, with more severe consequences than adults. The present study was designed to determine the distribution of assemblages A and B Giardia infection in children and adults, with the use of light microscopy and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) as diagnostic procedures, and to investigate its associations with clinical and epidemiological data collected from children and adult groups. This cross-sectional study was conducted from October 2012 to October 2013 by collecting fecal samples from 200 children and 200 adults complaining of diarrhea. Samples were subjected to parasitological examination by direct wet smear and formol-ether methods. Genotyping of G. doudenalis samples was conducted by PCR-RFLP analysis. Giardia duodenalis infection caused by assemblages A and B was identified in 60 samples, 34 from children and 26 from adults. Assemblage B was detected in 38 patients (63.34%), and assemblage A was detected in 22 patients (36.66%). Assemblage A was significantly more frequent in children with age range 2-8 yr, and assemblage B was higher in children with age range 6-16 yr old. Diarrhea frequency/day and recurrences per month affected patients infected with assemblage A (P value < 0.001) more frequently. Children infected with assemblage A presented significantly more severe diarrhea and dehydration than those infected with assemblage B (P value < 0.001). Although both Giardia assemblages A and B were identified in children and adults, assemblage A infected younger children more frequently and was more closely related to severe clinical manifestations than assemblage B.


Assuntos
Diarreia/parasitologia , Giardia/classificação , Giardíase/parasitologia , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Estudos Transversais , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Desidratação/parasitologia , Egito , Fezes/parasitologia , Feminino , Técnicas de Genotipagem , Giardia/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Recidiva , Adulto Jovem
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