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1.
Chem Commun (Camb) ; 55(77): 11619-11622, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501844

RESUMO

Mesoporous organosilica nanoparticles (PHT-PMO) have been prepared from an octa-triethoxysilylated Zn phthalocyanine precursor. These PHT-PMO nanoparticles had no dark toxicity but high phototoxicity when irradiated at 650 nm, and remarkable near-infrared phototoxicity when excited at 760 and 810 nm. The PHT-PMO were then aminated to promote electrostatic complexation with siRNA. Transfection experiments were performed upon NIR irradiation and photochemical internalization was very efficient, leading to 65% luciferase extinction in MCF-7 cancer cells expressing stable luciferase.


Assuntos
Indóis/química , Nanopartículas/química , Compostos Organometálicos/química , Fotoquimioterapia/métodos , RNA Interferente Pequeno/química , Silanos/química , Sobrevivência Celular , Cetrimônio/química , Humanos , Raios Infravermelhos , Luciferases/genética , Células MCF-7 , Processos Fotoquímicos , Porosidade , RNA Interferente Pequeno/metabolismo , Eletricidade Estática , Propriedades de Superfície
2.
J Agric Food Chem ; 67(40): 11129-11136, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31487456

RESUMO

4-Amion-2,2,6,6-tetramethylpiperidine (Temp) was grafted into sodium lignosulfonate (SL) to obtain hindered amine-modified lignosulfonate (SL-Temp). Then, the polymer surfactant (SL-Temp-CTAB) was prepared using cetyltrimethylammonium bromide (CTAB) and SL-Temp. Obtained SL-Temp-CTAB was used as an emulsifier to prepare a green emulsifiable concentrate (EC) of avermectin (AVM), which shows good emulsifying property and storage stability. The prepared AVM green EC can form AVM-loaded microspheres with nanometer particle size distribution after emulsification in water. After ultraviolet irradiation for 70 h, the AVM retention rate of the green EC prepared using SL-Temp-CTAB was 75.8%, which is much higher than that of commercial EC (0.4%) and the green EC prepared using unmodified SL (31.4%). Moreover, the AVM green EC prepared using SL-Temp-CTAB has slow-release performance, and the release equilibrium time is 5.3 times the commercial EC. Therefore, the newly prepared AVM green EC using a lignin-based functional emulsifier shows good antiphotolysis and slow-release performance compared to the traditional EC.


Assuntos
Aminas/química , Emulsificantes/síntese química , Lignina/química , Cetrimônio/química , Emulsificantes/química , Emulsões/química , Cinética , Lignina/análogos & derivados , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
3.
J Chromatogr A ; 1607: 460397, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31378525

RESUMO

Capillary electrophoresis has been used extensively for protein separations, but interactions of proteins with the negative charge on the surface of fused silica capillary create band broadening and diminish the separation efficiency. Coatings developed to mask the negative charge of the capillary affect the electroosmotic flow. The method presented in this work addresses these concerns through the use of a two-layer coating of a semi-permanent phospholipid substrate and cetyltrimethylammonium bromide (CTAB). When used alone, phospholipid coating suppresses the electroosmotic flow but cannot be used to simultaneously separate anionic and cationic proteins. When used alone, CTAB creates a dynamic coating that facilitates the separation of cationic proteins with good efficiency, but reduces the separation efficiency of anionic proteins. The use of a hybrid phospholipid-CTAB surface coating alleviates protein adsorption, as demonstrated through a comparison of protein separations obtained with a bare fused silica capillary. The hybrid phospholipid-CTAB surface enables high efficiency separations of cationic and anionic proteins simultaneously. This work verifies the role of the hydrophobic tail of CTAB in developing a stable coating with an electroosmotic flow of 3.14 × 10-4 cm2V-1s-1 (n = 10) from the cathode to the anode at a pH of 7. The coating yields a stable electroosmotic flow even after 2 h of flushing with background electrolyte devoid of CTAB (n = 3) and six consecutive protein injections with no flush sequence between runs. The coating can be used with background electrolytes with pH values ranging from 4 to 8 while maintaining 1% RSD (n = 10) in the electroosmotic flow for each background electrolyte. Six model proteins, lysozyme, ribonuclease A, α-chymotrypsinogen A, enolase, transferrin, and α-1-antitrypsin, with pI values ranging from 4.4 to 11 were used to demonstrate the stability of the phospholipid-CTAB coating, the lack of protein interaction with the wall, and the utility of the coating for the separation of proteins of similar isoelectric points and of protein isoforms.


Assuntos
Proteínas/isolamento & purificação , Adsorção , Ânions , Cátions , Cetrimônio/química , Eletro-Osmose , Eletroforese Capilar , Humanos , Concentração de Íons de Hidrogênio , Fosfolipídeos/química , Proteínas/química , Dióxido de Silício/química
4.
Molecules ; 24(13)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277526

RESUMO

At present, the management of Phytophthora capsici (P. capsici) mainly relies on chemical pesticides. However, along with the resistance generated by P. capsici to these chemical pesticides, the toxicity and non-degradability of this chemical molecule may also cause serious environmental problems. Herein, a new bio-based nano-antifungal material (CNC@CTAB) was made with coating hexadecyl trimethyl ammonium bromide (CTAB) on the surface of a cellulose nanocrystal (CNC). This material was then applied to the prevention of P. capcisi. This particle was facilely fabricated by mixing CTAB and sulfuric group modified CNC in an aqueous solvent. Compared to pure CTAB, the enrichment of CTAB on the CNC surface showed a better anti-oomycete activity both in vitro and in vivo. When CNC@CTAB was applied on P. capsici in vitro, the inhibition rate reached as high as 100%, while on the pepper leaf, the particle could also efficiently prevent the infection of P. capsici, and achieve a disease index as low as zero Thus, considering the high safety of CNC@CTAB in agricultural applications, and its high anti-oomycete activity against P. capsici, we believe that this CNC@CTAB has great application potential as a new green nano-fungicide in P. capsici management during the production of peppers or other vegetables.


Assuntos
Celulose/farmacologia , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Nanopartículas/química , Capsicum/efeitos dos fármacos , Capsicum/microbiologia , Cátions , Permeabilidade da Membrana Celular/efeitos dos fármacos , Cetrimônio/química , Condutividade Elétrica , Líquido Extracelular/química , Nanopartículas/ultraestrutura , Phytophthora , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Eletricidade Estática , Propriedades de Superfície
5.
Anticancer Res ; 39(7): 3621-3631, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262888

RESUMO

BACKGROUND/AIM: Cetrimonium bromide (CTAB), a quaternary ammonium surfactant, is an antiseptic agent against bacteria and fungi. However, the mechanisms by which its pharmacological actions affect epithelial-mesenchymal transition (EMT) in hepatocellular carcinoma (HCC) cells, such as adenocarcinoma in SK-HEP-1 cells, have not been investigated. We, thereby, investigated whether CTAB inhibits cellular mobility and invasiveness of human hepatic adenocarcinoma in SK-HEP-1 cells. MATERIALS AND METHODS: SK-HEP-1 cells were treated with CTAB, and subsequent migration and invasion were measured by wound healing and transwell assays. Protein expression was detected by immunoblotting analysis. RESULTS: Our data revealed that treatment of SK-HEP-1 cells with CTAB altered their mesenchymal spindle-like morphology. CTAB exerted inhibitory effects on the migration and invasion of SK-HEP-1 cells dose-dependently, and reduced protein levels of matrix metalloproteinase-2 (MMP-2), MMP-9, snail, slug, twist, vimentin, fibronectin, N-cadherin, Smad2, Smad3, Smad4, phosphoinositide-3-kinase (PI3K), p-PI3K, Akt, p-Akt, ß-catenin, mammalian target of rapamycin (mTOR), p-mTOR, p-p70S6K, p-extracellular signal-regulated kinases (ERK)1/2, p-p38 mitogen-activated protein kinase (MAPK) and p-c-Jun N-terminal kinase (JNK), but increased protein levels of tissue inhibitor matrix metalloproteinase-1 (TIMP-1), TIMP-2, claudin-1 and p-GSK3ß. Based on these observations, we suggest that CTAB not only inhibits the canonical transforming growth factor-ß (TGF-ß) signaling pathway though reducing SMADs (an acronym from the fusion of Caenorhabditis elegans Sma genes and the Drosophila Mad, Mothers against decapentaplegic proteins), but also restrains the non-canonical TGF-ß signaling including MAPK pathways like ERK1/2, p38 MAPK, JNK and PI3K. CONCLUSION: CTAB is involved in the suppression of TGF-ß-mediated mesenchymal phenotype and could be a potent medical agent for use in controlling the migration and invasion of hepatic adenocarcinoma.


Assuntos
Adenocarcinoma/metabolismo , Antineoplásicos/farmacologia , Cetrimônio/farmacologia , Neoplasias Hepáticas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adenocarcinoma/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Invasividade Neoplásica , Transdução de Sinais/efeitos dos fármacos
6.
Analyst ; 144(15): 4582-4588, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31236555

RESUMO

Plasmonic nanostructures have been broadly used for chemical detections, but their applications are limited by slow detection rates, insufficient visual resolution and sensitivity due to the chemical and structural stability of conventional plasmonic nanomaterials. It is thus essential to develop strategies to enhance the detection kinetics while promoting their excellent plasmonic properties. In this work, a colorimetric assay for HCHO measurement is developed based on the fact that HCHO can react with Tollens' reagent to anisotropically deposit a layer of silver shells onto the bone-shaped gold nanorod (Au NR) cores. Compared to the routine rod-shaped Au NRs, the bone-shaped Au NRs facilitate the deposition of Ag onto the sunken section due to their unique concave structures, giving rise to fast reaction kinetics and detection rate. It is also important to point out that the surface ligand exchange from CTAB to CTAC is helpful to accelerate the deposition of silver onto Au NRs, which significantly shortens the reaction time. The preferential deposition of Ag on the concave Au NRs induces more dramatic morphology changes and therefore promotes the plasmonic shift of the bone-shaped Au NRs and improves the sensing efficiency. Correspondingly, the apparent color of the solution changes from light gray to dark blue, purple, red, orange and finally to yellow as the longitudinal localized surface plasmon resonance (LSPR) band shifts from 710 to 500 nm along with the emergence of a new LSPR band at 400 nm almost covering the full visible region. The colorimetric method developed enables sensitive detection of HCHO with a low detection limit (1 nM), wide linear range (0.1-50 µM), high visual resolution and good specificity against other common indoor gases. It was successfully applied to the detection of gaseous HCHO present in the air collected from a furniture plaza, showing its potential practicality for on-site HCHO analysis.


Assuntos
Poluentes Atmosféricos/análise , Cetrimônio/química , Formaldeído/análise , Ouro/química , Nanotubos/química , Hidróxido de Amônia/química , Anisotropia , Colorimetria/métodos , Limite de Detecção , Nitrato de Prata/química , Ressonância de Plasmônio de Superfície/métodos
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 313-318, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31054495

RESUMO

The interactions between cetyltrimethylammonium bromide (CTAB) and hen egg white lysozymes (HEWL) was carried out to investigate protein-surfactant interaction mechanisms while both exist in the overall same charged state. The interactions between CTAB and the HEWL were examined with circular dichroism (CD), dynamic light scattering (DLS), fluorescence spectroscopy, and computational docking at a pH9.0 at room temperature. The far-UV CD and fluorescence results revealed that CTAB at concentrations from 0.15 to 10.0mM influenced the secondary as well as the tertiary structure of HEWL. The secondary structure of the HEWL was retained, while the tertiary structure of the HEWL was disrupted in the CTAB-treated samples at pH9.0. The hydrodynamic radii of the HEWL were also expanded in the presence of CTAB. Molecular docking studies showed that CTAB formed one electrostatic and four hydrophobic interactions, as well as one carbon hydrogen bond with HEWL. The data obtained from spectroscopic and computational studies demonstrated that the positively charged head and 18­carbon alkyl chain of the CTAB interacted through weak electrostatic and strong hydrophobic interactions.


Assuntos
Cetrimônio/metabolismo , Muramidase/metabolismo , Tensoativos/metabolismo , Animais , Galinhas , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Simulação de Acoplamento Molecular , Muramidase/química , Ligação Proteica , Conformação Proteica/efeitos dos fármacos , Desdobramento de Proteína/efeitos dos fármacos , Eletricidade Estática
8.
Enzyme Microb Technol ; 127: 58-64, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31088617

RESUMO

Cadaverine, also known as 1,5-pentanediamine, is an important platform chemical with a wide range of applications and can be produced either by fermentation or bioconversion. Bioconversion of cadaverine from l-lysine is the preferred method because of its many benefits, including rapid reaction time and an easy downstream process. In our previous study, we replaced pyridoxal-5-phosphate (PLP) with pyridoxal kinase (PdxY) along with pyridoxal (PL) because it could achieve 80% conversion with 0.4 M of l-lysine in 6 h. However, conversion was sharply decreased in the presence of high concentrations of l-lysine (i.e., 1 M), resulting in less than 40% conversion after several hours. In this study, we introduced an ATP regeneration system using polyphosphate kinase (ppk) into systems containing cadaverine decarboxylase (CadA) and PdxY for a sufficient supply of PLP, which resulted in enhanced cadaverine production. In addition, to improve transport efficiency, the use of surfactants was tested. We found that membrane permeabilization via hexadecyltrimethylammonium bromide (CTAB) increased the yield of cadaverine in the presence of high concentrations of l-lysine. By combining these two strategies, the ppk system and addition of CTAB, we enhanced cadaverine production up to 100% with 1 M of l-lysine over the course of 6 h.


Assuntos
Trifosfato de Adenosina/metabolismo , Cadaverina/metabolismo , Cetrimônio/metabolismo , Escherichia coli/metabolismo , Fosfato de Piridoxal/metabolismo , Biotransformação , Escherichia coli/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo
9.
Eur J Pharm Sci ; 135: 91-102, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31078644

RESUMO

Montmorillonite Clay (MMT) is aimed to develop as an orally administrable drug delivery vehicle with enhanced efficacy. Aiming to enhance the therapeutic index of methotrexate, curcumin is concomitantly used with methotrexate in the present study. Being folate antagonist in nature, methotrexate is internalized into cells by folate receptor (FR); which is over-expressed in certain human cancer cells such as cervical carcinoma cells (HeLa). Firstly, montmorillonite Clay (MMT) is organically modified (OMMT) with cetyl trimethyl ammonium bromide (CTAB) and used to intercalate curcumin and methotrexate separately, designated as OMMT-Cur and OMMT-MTX, respectively. XRD pattern demonstrated successful intercalation of therapeutics and an increase in clay interlayer distance facilitated by CTAB. The dissolution kinetics of methotrexate follows Higuchi model for both Simulated Gastric Fluid (SGF) and Simulated Intestinal Fluid (SIF), while the release kinetics for curcumin fitted into Higuchi model for SGF and Hixson-Crowell model for SIF, respectively. OMMT-MTX are able to discriminate FR-positive HeLa cells from FR-negative breast cancer cells (MCF7); irrespective of alike cellular phenotypes. Further, the pre-treatment of HeLa cells with curcumin improves its sensitivity towards methotrexate causing a greater killing of the Hela cells. Together, the results propose the concomitant use of curcumin and methotrexate for successfully targeting highly invasive FR-positive carcinomas by means of folate receptor using MMTs.


Assuntos
Antineoplásicos/administração & dosagem , Bentonita/química , Argila/química , Curcumina/farmacologia , Portadores de Fármacos/química , Antagonistas do Ácido Fólico/administração & dosagem , Metotrexato/administração & dosagem , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Cetrimônio/química , Liberação Controlada de Fármacos , Receptor 2 de Folato/metabolismo , Antagonistas do Ácido Fólico/química , Células HeLa , Humanos , Células MCF-7 , Metotrexato/química
10.
Anal Chim Acta ; 1067: 147-154, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31047146

RESUMO

Surfactant bilayers or admicelles at the solid surface-liquid interface inside 50-200 µm inner diameter (i.d.) open-tube fused-silica capillaries were developed as 'soft' stationary pseudophases for the liquid chromatographic (LC) separations of neutral and charged analytes. Admicelles were formed in-situ from buffered aqueous mobile phases with cetytrimethylammonium bromide at concentrations between the critical surface aggregation concentration and critical micelle concentration, which were determined by electroosmotic flow measurements using capillary electrophoresis. There were no micelles in the mobile phase solution. Also, there was no solid phase that is classically required in LC. Pressure and voltage driven modes or open-tubular admicellar liquid chromatography (OT-AMLC) and electrochromatography, respectively were proposed based on the separation of neutral analytes. The parameters (i.e., pH, concentration of surfactant, salt, and methanol in the mobile phase and capillary i.d.) that affected the surprising chromatographic effect of admicelles at the interface were investigated. The analytical performance of OT-AMLC for small molecules were found acceptable. Applications to environmental water and biological (HepG cell line metabolism media) samples analysis with appropriate sample preparation procedures were also conducted. The use of pseudophases at the solid surface-liquid interface could be a viable solution to problems associated with the use of solid stationary or support materials in nano- and micro-liquid chromatography and electrochromatography.


Assuntos
Eletrocromatografia Capilar/métodos , Micelas , Eletrocromatografia Capilar/instrumentação , Cetrimônio/química , Cromatografia Líquida , Meios de Cultura/química , Células Hep G2 , Humanos , Dióxido de Silício/química , Poluentes Químicos da Água/química
11.
Colloids Surf B Biointerfaces ; 180: 177-185, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31048243

RESUMO

One of the main toxicities associated to intravenous administration of amphiphilic drugs is pronounced hemolytic activity. To overcome this limitation, we investigated the anti-hemolytic properties of polymeric micelles of Pluronics, triblock copolymers of poly(ethylene oxide) and poly(propylene oxide). We studied the encapsulation of the amphiphilic compound miltefosine (HePC) into polymeric micelles of Pluronics F108, F68, F127, L44, and L64. In vitro hemolysis indicated that, among the five copolymers studied, only F127 completely inhibited hemolytic effect of HePC at 50 µg/mL, this effect was also observed for other two amphiphilic molecules (cetyltrimethylammonium bromide and cethylpyridinium chloride). To better understand this interaction, we analyzed the HC50 (concentration causing 50% of hemolysis) for HePC free and loaded into F127 micelles. Copolymer concentration influenced the hemolytic profile of encapsulated HePC; for F127 the HC50 increased relative to free HePC (40 µg/mL) up to 184, 441, 736 and 964 µg/mL, for 1, 3, 6 and 9% F127, respectively. Interestingly, a linear relationship was found between HC50-HePC and F127 concentration. At 3% of F127, it is possible to load up to 300 µg/mL of HePC with no hemolytic effect. By achieving this level of hemolysis protection, a promising application is on the view, bringing the parenteral use of HePC and other amphiphilic drugs. Additionally, small-angle X-ray scattering (SAXS) was used to asses structural information on the interactions between HePC and F127 micelles.


Assuntos
Antifúngicos/farmacologia , Portadores de Fármacos , Hemólise/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Tensoativos/farmacologia , Animais , Antifúngicos/química , Cetrimônio/química , Cetrimônio/farmacologia , Cetilpiridínio/química , Cetilpiridínio/farmacologia , Relação Dose-Resposta a Droga , Composição de Medicamentos/métodos , Eritrócitos/efeitos dos fármacos , Micelas , Fosforilcolina/química , Fosforilcolina/farmacologia , Poloxâmero/química , Poloxâmero/farmacologia , Ovinos , Tensoativos/química
12.
Mikrochim Acta ; 186(5): 322, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049692

RESUMO

A specific and sensitive colorimetric aptasensor is described for the determination of Malachite Green (MG). It is exploiting the inhibition of the peroxidase-like activity of gold nanoparticles (AuNPs). The AuNPs act as enzyme mimics that catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to yield a dark blue solution. The catalytic activity is inhibited by hexadecyl trimethyl ammonium ion, specifically by cetyltrimethylammonium bromide (CTAB), which causes the aggregation of AuNPs. If a (negatively charged) RNA-aptamer against MG is added, it binds to the positively charged CTAB and prevents aggregation. This enhances the enzyme mimicking activity of the AuNPs and leads to the formation of a dark blue solution. However, in the presence of MG, the aptamer binds to MG, and leads to the aggregation of AuNPs again. The aggregated AuNPs possess a light blue color. A colorimetric method (best performed at 650 nm) was work out that can detect MG in a concentration range from 10 to 500 nmol L-1. The detection limit based on 3σ/k criterion is 1.8 nmol L-1. The assay is highly specific and accurate. Recoveries from spiked real samples (aquaculture water) ranged from 80% to 120%. Graphical abstract Based on the inhibition of cetyltrimethyal ammonium ion and the enhancement of RNA-aptamer, the differences of the peroxidase-like activities of AuNPs can be greatly enlarged with and without MG, by which a colorimetric aptasensor can be constructed for the detection of Malachite Green (MG).


Assuntos
Aptâmeros de Nucleotídeos/química , Cetrimônio/química , Colorimetria/métodos , Ouro/química , Nanopartículas Metálicas/química , Peroxidase/química , Corantes de Rosanilina/análise , Benzidinas/química , Catálise , Cor , Peróxido de Hidrogênio/química , Limite de Detecção , Oxirredução
13.
PLoS One ; 14(4): e0216117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31026266

RESUMO

Using a mixture of neutral primary amine dehydroabietylamine (DHAA) and long-chain cetyltrimethyl ammonium bromide (CTAB) as the template, ordered lamellar supermicroporous silicas were synthesized with NaOH as the base source and tetraethylorthosilicate (TEOS) as the silica source. The concentrations of DHAA, CTAB, and NaOH in the synthesis system had great effects on the structural properties of the samples. When the molar ratio of components was nTEOS:nCTAB:nDHAA:nNaOH:nH2O = 1:0.114:0.00457:0.5:60, the material showed a lamellar phase with the highest ordering degree. By adding only a trace amount of DHAA into the synthesis system, the structure of the samples could be transformed from cubic phase to lamellar phase, since the added DHAA solubilized in CTAB micelles to change the effective surfactant ion pair packing parameter. The dosage of CTAB should be moderate; too high or too low will decay the ordering degree of the lamellar structure.A much higher concentration of NaOH resulted in an ethanol-rich solvent in which the DHAA did not solubilize in the micelles of CTAB, but adsorbed at the hydrophilic headgroup-solvent interface. Accordingly, a structural transformation from lamellar phase to hexagonal phase occurred.


Assuntos
Dióxido de Silício/química , Dióxido de Silício/síntese química , /química , Cátions , Cetrimônio/química , Nitrogênio/química , Porosidade , Hidróxido de Sódio/química , Temperatura Ambiente , Difração de Raios X
14.
Am J Obstet Gynecol ; 221(3): 261.e1-261.e20, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30954518

RESUMO

BACKGROUND: Direct comparison metaanalyses have reported benefits with presurgical vaginal preparation before cesarean delivery for the reduction of endometritis. These reports did not perform a multitreatment comparison of the various antiseptic solutions assessed in previous studies. OBJECTIVE: The purpose of this study was to review the literature systematically and quantitate and summarize indirectly the comparative efficacy of antiseptic formulations and their concentrations that are used for the preparation of the vagina before cesarean delivery in the prevention of endometritis and other infectious complications. STUDY DESIGN: We used MEDLINE, EMBASE (from their inception to November 2018) and Cochrane databases, biographies, and conference proceedings. We used randomized clinical trials of patients who underwent surgical preparation of the vagina with antiseptic formulations before cesarean delivery with the aim of reducing the risk of infectious morbidity. Our systematic review was registered and followed the Preferred Reporting Items for Systematic Review and Meta-analysis Extension for network meta-analysis guidelines. Network meta-analysis was performed with computerized software and used user-written programs to assess consistency, inconsistency, ranking probabilities, and graphing results. Direct and indirect pairwise comparisons of the various formulations and their concentrations were performed with the use of multivariate random-effects models and metaregression. A frequentist inference method was employed for the fitted model to estimate the ranking probabilities. Subgroup analyses for patients in labor, not in labor, and with ruptured membranes were conducted. RESULTS: For the prevention of endometritis, we identified 23 studies that comprised 7097 women who were allocated to the following treatments: povidone-iodine (1%, 5%, 10%), chlorhexidine (0.2%, 0.4%), metronidazole gel, cetrimide, or normal saline solution/no treatment. Direct and indirect pairwise comparisons indicated that, when compared with saline solution or no treatment, all antiseptic formulations decreased rates of endometritis (5.2% vs 9.1%; odds ratio, 0.48; 95% confidence interval, 0.35-0.65; 22 studies/6994 women). Individually, povidone-iodine (odds ratio, 0.43; 95% confidence interval, 0.28-0.64; 16 studies/5968 women), cetrimide (odds ratio, 0.34; 95% confidence interval, 0.13-0.90; 1 study/200 women), and metronidazole (odds ratio, 0.38; 95% confidence interval, 0.16-0.90; 1 study/224 women) significantly reduced the risk of endometritis. Rankings of vaginal preparations indicated that povidone-iodine 1% had the highest probability (72.7%) of being the most effective treatment for the prevention of endometritis. For the secondary outcomes of postoperative wound infection and fever, a significant reduction was found only with povidone-iodine (odds ratio, 0.61; 95% confidence interval, 0.48-0.78; 16 studies/5968 women; and odds ratio, 0.58; 95% confidence interval, 0.40-0.83; 12 studies/4667 women). Subgroup analyses also found that povidone-iodine significantly reduced risk of endometritis for women in labor (odds ratio, 0.42; 95% confidence interval, 0.20-0.88; 5 studies/1211 women), with ruptured membranes(odds ratio, 0.21; 95% confidence interval, 0.10-0.44; 4 studies/476 women), and undergoing planned cesarean delivery (odds ratio, 0.39; 95% confidence interval, 0.27-0.57; 8 studies/1825 women). CONCLUSION: Among patients who underwent cesarean delivery, presurgical vaginal irrigation with povidone-iodine had the highest probability of reducing the risk of endometritis, postoperative wound infections, and fever.


Assuntos
Anti-Infecciosos Locais/uso terapêutico , Cesárea , Endometrite/prevenção & controle , Povidona-Iodo/uso terapêutico , Cetrimônio/uso terapêutico , Clorexidina/uso terapêutico , Feminino , Humanos , Metronidazol/uso terapêutico , Meta-Análise em Rede
15.
Mater Sci Eng C Mater Biol Appl ; 99: 37-46, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889711

RESUMO

Novel biosensor architecture based on nanocrystalline cellulose (NCC)/CdS quantum dots (QDs) nanocomposite was developed for phenol determination. This nanocomposite was prepared with slight modification of nanocrystalline cellulose (NCC) with cationic surfactant of cetyltriammonium bromide (CTAB) and further decorated with 3-mercaptopropionic acid (3-MPA) capped CdS QDs. The nanocomposite material was then employed as scaffold for immobilization of tyrosinase enzyme (Tyr). The electrocatalytic response of Tyr/CTAB-NCC/QDs nanocomposite towards phenol was evaluated using differential pulse voltammetry (DPV). The current response obtained is proportional to the concentration of phenol which attributed to the reduction of o-quinone produced at the surface of the modified electrode. Under the optimal conditions, the biosensor exhibits good linearity towards phenol in the concentration range of 5-40 µM (R2 = 0.9904) with sensitivity and limit of detection (LOD) of 0.078 µA/µM and 0.082 µM, respectively.


Assuntos
Técnicas Biossensoriais/métodos , Celulose/química , Monofenol Mono-Oxigenase/metabolismo , Nanopartículas/química , Fenol/análise , Pontos Quânticos/química , Calibragem , Carbono , Cetrimônio/química , Técnicas Eletroquímicas , Eletrodos , Nanopartículas/ultraestrutura , Impressão , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
16.
J Appl Microbiol ; 126(5): 1391-1401, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30828950

RESUMO

AIMS: To investigate effects of the cationic surfactant cetyltrimethylammonium bromide (CTAB), a disinfectant, on spores of Bacillus species. METHODS AND RESULTS: The ability of CTAB to trigger release of Bacillus spores' large depot of dipicolinic acid (DPA) in a 1 : 1 chelate with Ca2+ (CaDPA), and to kill spores was investigated. CTAB-triggered CaDPA release from spores of Bacillus subtilis, Bacillus cereus and Bacillus megaterium, but was not followed by completion of germination. CaDPA release triggered by CTAB increased at higher temperatures, and was optimal for B. subtilis spores at pH 9·4 and 30 µg ml-1 CTAB. CTAB also killed Bacillus spores as shown by plate counts and vital staining of treated dormant spores, and after their germination. However, B. cereus and B. megaterium spores were more CTAB-sensitive than were B. subtilis spores. CaDPA release from and killing of CTAB-treated spores of isogenic B. subtilis mutants lacking germination proteins was also examined, and compared with effects of the well-known germinant dodecylamine on spores, to determine how CTAB exerts its effects on spores. CONCLUSIONS: The results of this investigation showed that CTAB kills spores of three Bacillus species, perhaps by damaging the spore inner membrane, although it is also possible that some killing by this agent follows its triggering of spore germination. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this work indicate that CTAB is also a disinfectant, but also a sporicide, and may be a useful adjunct in spore decontamination, especially at higher temperatures.


Assuntos
Bacillus/efeitos dos fármacos , Cetrimônio/farmacologia , Desinfetantes/farmacologia , Aminas/farmacologia , Bacillus cereus/efeitos dos fármacos , Bacillus megaterium/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Descontaminação , Temperatura Alta , Ácidos Picolínicos/análise , Esporos Bacterianos/química , Esporos Bacterianos/efeitos dos fármacos , Tensoativos/metabolismo
17.
Eur J Pharm Sci ; 131: 39-49, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30735821

RESUMO

Physicochemical characteristics and in vitro anti-skin aging activity of gallic acid loaded in niosomes were investigated. Gallic acid was loaded in neutral (Brij 52/cholesterol at 7:3) and cationic CTAB niosomes (Brij 52/cholesterol/cetyltrimethylammonium bromide at 7:3:0.65). The maximum loading capacity and entrapment efficiency of gallic acid were 3.5, 4.48 ±â€¯2.10 in neutral and 50%, w/w, 10.94 ±â€¯0.78% in cationic CTAB niosomes, respectively. All gallic acid loaded in niosomes showed the unilamellar structure under transmission electron microscope with size range of 131.23-508.03 nm at initial and after storage for 3 months. The highest remaining percentage of gallic acid at all storage temperatures after 3 months was about 77% when loaded in the cationic CTAB niosome, whereas gallic acid in solution was about 64%. The release profiles of gallic acid loaded in neutral and cationic CTAB niosomes revealed the gradual release in 24 h. The cytotoxicity of gallic acid loaded in neutral and cationic CTAB niosomes appeared the non-cytotoxic effect in B16F10 melanoma cells and human skin fibroblasts. The cationic CTAB niosome loaded with gallic acid demonstrated the highest anti-skin aging activity, including melanin suppression effect (55.92 ±â€¯4.92% of control) by inhibition of tyrosinase (53.18 ±â€¯3.67% of control) and tyrosinase-related protein-2 (24.61 ±â€¯7.92% of control), antioxidant (87.03 ±â€¯0.99% cell viability) and inhibition of matrix metalloproteinase-2 (38.46 ±â€¯1.53% of control). This study has demonstrated the superior stability and anti-skin aging activity of gallic acid loaded in cationic CTAB niosome for potential utilization in pharmaceutical and cosmetic products.


Assuntos
Cetrimônio/administração & dosagem , Ácido Gálico/administração & dosagem , Inibidores de Metaloproteinases de Matriz/administração & dosagem , Envelhecimento da Pele , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cetrimônio/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ácido Gálico/química , Humanos , Lipossomos , Metaloproteinase 2 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/química , Melaninas/metabolismo , Camundongos , Pele/citologia
18.
Int J Pharm ; 559: 410-419, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30738129

RESUMO

This study aimed to optimize the preparation conditions for cetyltrimethylammonium bromide-modified Polygonatum sibiricum polysaccharide cubosomes (CTAB-modified PSP-Cubs) by response surface methodology (RSM). Glyceryl-monooleate (GMO) was used as the lipid base for the cubosomes. The optimal preparation conditions of CTAB-modified PSP-Cubs were as follows: the mass percentage of PSP to GMO (X1), Poloxamer 407 (F127) to GMO (X2) and water to GMO (X3) was 1.4%, 9% and 50%, respectively. The encapsulation efficiency (EE) of CTAB-modified PSP-Cubs under the experimental conditions was 62.4 ±â€¯3.6%, which was close to our predicted value. The particle size, polydispersity index (PDI) and zeta potential of CTAB-modified PSP-Cubs were 427.7 ±â€¯8.0 nm, 0.236 ±â€¯0.024 and 19.2 ±â€¯0.4 mV, respectively. Specific modifications were able to slow down in vitro release behaviors and reduce cytotoxicity to some extent. The effects of CTAB-modified PSP-Cubs on splenic lymphocytes were also investigated. When splenic lymphocytes were treated with CTAB-modified PSP-Cubs together with LPS or PHA, the results showed more favorable effects on cellular proliferation than blank cubosomes or free PSP at certain concentrations.


Assuntos
Cetrimônio/química , Cetrimônio/farmacologia , Linfócitos/efeitos dos fármacos , Polygonatum/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Baço/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Glicerídeos/química , Glicerídeos/farmacologia , Camundongos , Tamanho da Partícula , Poloxâmero/química
19.
ACS Appl Mater Interfaces ; 11(10): 10356-10363, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30789700

RESUMO

Magnetic mesoporous silica microspheres with core-shell structure and large pores are highly desired in macromolecules delivery and biocatalysis, biospeparation, and adsorption. In this work, a controllable solvent evaporation induced solution-phase interface co-assembly approach was developed to synthesize core-shell structural magnetic mesoporous silica microspheres with ultralarge mesopore size (denoted as LP-MMS). The synthesis was achieved by employing large-molecular-weight amphiphilic block copolymers poly(ethylene oxide)- block-poly(methyl methacrylate) (PEO- b-PMMA) and small surfactant cetyltrimethylammonium bromide as co-templates, which can co-assemble with silica source in tetrahydrofuran/water solutions. The obtained LP-MMS microspheres possess uniform rasberry-like morphology with a diameter of 600 nm, large primary spherical mesopores (ca. 36 nm), large specific surface area (348 m2/g), high specific pore volume (0.59 cm3/g), and fast magnetic responsivity with high magnetization (15.9 emu/g). The mesopore morphology can be transformed from spherical to cylindrical through introducing a shearing force during the interfacial co-assembly in the synthesis system. The designed LP-MMS microspheres turn out to be good carriers for enzyme (trypsin) immobilization with a high loading capacity of 80 µg/mg and demonstrate excellent biocatalysis efficiency up to 99.1% for protein digestion within 30 min and good recycling stability with negligible decay in digestion efficiency after reuse for five times.


Assuntos
Biocatálise , Compostos de Cálcio/química , Enzimas Imobilizadas/química , Silicatos/química , Tripsina/química , Cetrimônio/química , Magnetismo , Microscopia Eletrônica de Transmissão , Microesferas , Polímeros/química , Polimetil Metacrilato/química , Propriedades de Superfície
20.
Mikrochim Acta ; 186(3): 194, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30778721

RESUMO

A fluorescent nanoprobe is designed for the determination of carbamazepine (CBZ) in exhaled breath condensate (EBC) of patients receiving CBZ. The probe consists of copper nanoclusters (Cu NCs) coated with cetyl trimethylammonium bromide. The interaction of probe with CBZ results in blocking non-radiative e-/h+ recombination defect sites on the surface of Cu NCs and consequently enhancing the blue-green fluorescence of Cu NCs (excitation/emission wavelengths: 290/480 nm). The experimental conditions were optimized using a response surface methodology (central composite design). Under the optimized conditions, the calibration plot is linear in the 0.2 to 20 µg mL-1 CBZ concentration range and the detection limit is as low as 0.08 µg mL-1. The intra-day and inter-day relative standard deviations for six replicated measurements of 10 µg mL-1 CBZ are 3.9% and 4.8%, respectively. The method was applied for the determination of CBZ level in EBC of patients receiving CBZ. The accuracy of the method was confirmed by HPLC-UV analysis as a reference method. Graphical abstract Graphical abstract contains poor quality and small text inside the artwork. Please do not re-use the file that we have rejected or attempt to increase its resolution and re-save. It is originally poor, therefore, increasing the resolution will not solve the quality problem. We suggest that you provide us the original format. We prefer replacement figures containing vector/editable objects rather than embedded images. Preferred file formats are eps, ai, tiff and pdf. "Figures 1 contains poor quality of text inside the artwork. Please do not re-use the file that we have rejected or attempt to increase its resolution and re-save. It is originally poor, therefore, increasing the resolution will not solve the quality problem. We suggest that you provide us the original format. We prefer replacement figures containing vector/editable objects rather than embedded images. Preferred file formats are eps, ai, tiff and pdf.A new PDF format of Graphical Abstract was provided in attachment section. Schematic presentation of cetyl trimethylammonium bromide coated copper nanocluster's response to carbamazepine.


Assuntos
Carbamazepina/análise , Cetrimônio/química , Cobre/química , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais , Testes Respiratórios/métodos , Cromatografia Líquida de Alta Pressão , Humanos , Limite de Detecção , Tamanho da Partícula , Espectrometria de Fluorescência , Propriedades de Superfície
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