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1.
Int J Nanomedicine ; 15: 6935-6944, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061360

RESUMO

Introduction: Nanoparticle solutions have been studied to improve antimicrobial effect. The aim of this study was to develop, characterize, and evaluate the in vitro and in vivo antiseptic efficacy of 0.25% aqueous-based chlorhexidine nanoemulsion (NM-Cl 0.25% w/v). Methods: The NM-Cl 0.25% w/v (2.5mg/mL) and free chlorhexidine nanoemulsion (FCN; same composition of NM-Cl without the molecule of chlorhexidine) were synthetized by the spontaneous emulsification method. Characterization analyses of physical and chemical properties were performed. The NM-Cl 0.25% w/v was compared with chlorhexidine 0.5% alcohol base (CS-Cl 0.5%) in vitro studies (microdilution study and kill curve study), and in vivo study (antisepsis of rats dorsum). Kruskal-Wallis test was used between groups and inside the same group, at different sample times and the Mann-Whitney test was performed when difference was detected. Results: The NM-Cl 0.25% w/v presented adequate physicochemical characteristics for a nanoemulsion, revealing a more basic pH than FCN and difference between zeta potential of NM-Cl 0.25% w/v and FCN. The NM-Cl 0.25% w/v and CS-Cl 0.5% solutions were more effective on Gram-positive than on Gram-negative bacteria (p≤0.05). NM-Cl 0.25% w/v presented upper antiseptic effect in the microdilution study and residual antiseptic effect was maintained for a longer time when compared to CS-Cl 0.5% (kill curve study). The four-fold (minimal inhibitory concentration) of NM-Cl 0.25% were the formulations with most durable effect within those tested, presenting residual effect until T6 for both bacteria. In the in vivo study, both formulations (NM-Cl 0.25% w/v and CS-Cl 0.5%) had a reduction of the microorganisms in the skin of the rats (p<0.0001) not revealing any difference between the formulations at different times, showing the antiseptic effect of NM-Cl (p≤0.05). Conclusion: Both in vitro and in vivo experiments demonstrated that NM-Cl showed promising future as an antiseptic for cutaneous microbiota.


Assuntos
Anti-Infecciosos Locais/farmacologia , Clorexidina/farmacologia , Emulsões/química , Nanoestruturas/química , Animais , Anti-Infecciosos Locais/química , Clorexidina/química , Emulsões/farmacologia , Etanol/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Nanoestruturas/uso terapêutico , Ratos Wistar , Pele/efeitos dos fármacos , Pele/microbiologia
2.
Proc Natl Acad Sci U S A ; 117(29): 17011-17018, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32636271

RESUMO

Few antibiotics are effective against Acinetobacter baumannii, one of the most successful pathogens responsible for hospital-acquired infections. Resistance to chlorhexidine, an antiseptic widely used to combat A. baumannii, is effected through the proteobacterial antimicrobial compound efflux (PACE) family. The prototype membrane protein of this family, AceI (Acinetobacter chlorhexidine efflux protein I), is encoded for by the aceI gene and is under the transcriptional control of AceR (Acinetobacter chlorhexidine efflux protein regulator), a LysR-type transcriptional regulator (LTTR) protein. Here we use native mass spectrometry to probe the response of AceI and AceR to chlorhexidine assault. Specifically, we show that AceI forms dimers at high pH, and that binding to chlorhexidine facilitates the functional form of the protein. Changes in the oligomerization of AceR to enable interaction between RNA polymerase and promoter DNA were also observed following chlorhexidine assault. Taken together, these results provide insight into the assembly of PACE family transporters and their regulation via LTTR proteins on drug recognition and suggest potential routes for intervention.


Assuntos
Acinetobacter baumannii , Antibacterianos , Proteínas de Bactérias , Clorexidina , Proteínas de Membrana Transportadoras , Acinetobacter baumannii/química , Acinetobacter baumannii/enzimologia , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Clorexidina/química , Clorexidina/metabolismo , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/metabolismo , Resistência Microbiana a Medicamentos , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/metabolismo , Ligação Proteica , Multimerização Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo
3.
Niger J Clin Pract ; 23(3): 381-385, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32134039

RESUMO

Objectives: This study aimed to compare the effect of different solutions on the removal of orange-brown precipitate with or without ultrasonic activation. Materials and Methods: One hundred and twenty extracted maxillary anterior teeth were instrumented. In experimental groups (n = 10), canals were flushed with 17% EDTA, 10% citric acid, 1% phytic acid, 96% alcohol and distilled water either using syringe irrigation or ultrasonic activation, after creating orange-brown precipitate. Teeth were sectioned longitudinally and subjected to stereomicroscopic analysis. The amount of precipitate was scored and the data were analyzed (P = 0.05). Results: There were no differences detected among the tested solutions (P > 0.05). There was a significant difference between ultrasonically activated irrigation and syringe irrigation for EDTA and distilled water in coronal, middle portions (P < 0.05). Conclusions: Ultrasonic activation significantly improved the precipitate removal capacity of EDTA and DW. Tested solutions were similarly effective regarding the removal of the precipitate.


Assuntos
Clorexidina/química , Hipoclorito de Sódio/química , Sonicação/métodos , Dente/química , Humanos , Preparo de Canal Radicular
4.
Braz Oral Res ; 34: e001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022221

RESUMO

This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Assuntos
Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Fabaceae/química , Óleos Vegetais/química , Análise de Variância , Clorexidina/química , Resinas Compostas/química , Cimentos Dentários/química , Infiltração Dentária , Dentina/química , Emulsões/química , Humanos , Teste de Materiais , Reprodutibilidade dos Testes , Cimentos de Resina/química , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração
5.
Molecules ; 25(2)2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31963668

RESUMO

Chlorhexidine (CHX) and octenidine (OCT), antimicrobial compounds used in oral care products (toothpastes and mouthwashes), were recently revealed to interfere with human sex hormone receptor pathways. Experiments employing model organisms-white-rot fungi Irpex lacteus and Pleurotus ostreatus-were carried out in order to investigate the biodegradability of these endocrine-disrupting compounds and the capability of the fungi and their extracellular enzyme apparatuses to biodegrade CHX and OCT. Up to 70% ± 6% of CHX was eliminated in comparison with a heat-killed control after 21 days of in vivo incubation. An additional in vitro experiment confirmed manganese-dependent peroxidase and laccase are partially responsible for the removal of CHX. Up to 48% ± 7% of OCT was removed in the same in vivo experiment, but the strong sorption of OCT on fungal biomass prevented a clear evaluation of the involvement of the fungi or extracellular enzymes. On the other hand, metabolites indicating the enzymatic transformation of both CHX and OCT were detected and their chemical structures were proposed by means of liquid chromatography-mass spectrometry. Complete biodegradation by the ligninolytic fungi was not achieved for any of the studied analytes, which emphasizes their recalcitrant character with low possibility to be removed from the environment.


Assuntos
Anti-Infecciosos Locais/metabolismo , Biodegradação Ambiental , Clorexidina/metabolismo , Fungos/metabolismo , Piridinas/metabolismo , Clorexidina/química , Assistência Odontológica , Humanos , Metabolômica/métodos , Piridinas/química , Transformação Genética
6.
J Appl Oral Sci ; 28: e20190039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939520

RESUMO

OBJECTIVE: This study aimed to evaluate the physical properties and antifungal activities of polymethyl methacrylate (PMMA) acrylic resins after the incorporation of chlorhexidine diacetate salt (CDA). METHODOLOGY: First, acrylic resin specimens were fabricated with Vipi Cor® and DuraLay® resins with and without the incorporation of 0.5%, 1.0% or 2.0% CDA. The residual monomer and CDA release were measured at intervals ranging from 2 hours to 28 days using ultraviolet spectrometry combined with high-performance liquid chromatography. The antifungal activity against C. albicans was evaluated with the agar diffusion method. Fourier transform infrared spectroscopy was used to analyze the degree of resin conversion. Finally, the water sorption values of the resins were also measured. RESULTS: The incorporated CDA concentration significantly changed the rate of CDA release (p<0.0001); however, the brand of the material appeared to have no significant influence on drug release. Subsequently, the inhibition zones were compared between the tested groups and within the same brand, and only the comparisons between the CDA 2% and CDA 1% groups and between the CDA 1% and CDA 0.5% groups failed to yield significant differences. Regarding the degrees of conversion, the differences were not significant and were lower only in the CDA 2% groups. Water sorption was significantly increased at the 1.0% and 2.0% concentrations. CONCLUSIONS: We concluded that the incorporation of CDA into PMMA-based resins enabled the inhibition of C. albicans growth rate, did not alter the degrees of conversion of the tested resins and did not change the release of residual monomers.


Assuntos
Antifúngicos/química , Clorexidina/análogos & derivados , Polimetil Metacrilato/química , Resinas Acrílicas/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Clorexidina/química , Clorexidina/farmacologia , Cromatografia Líquida de Alta Pressão , Teste de Materiais , Polimetil Metacrilato/farmacologia , Valores de Referência , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo , Água/química
7.
IET Nanobiotechnol ; 14(1): 14-18, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31935672

RESUMO

In this study, chlorhexidine (CHX)-silver (Ag) hybrid nanoparticles (NPs) coated gauze was developed, and their bactericidal effect and in vivo wound healing capacities were tested. A new method was developed to synthesise the NPs, wherein Ag nitrate mixed with sodium (Na) metaphosphate and reduced using Na borohydride. Finally, CHX digluconate was added to form the hybrid NPs. To study the antibacterial efficacy of particles, the minimal inhibition concentration and biofilm degradation capacity against Gram-positive and Gram-negative bacteria was studied using Escherichia coli and Staphylococcus aureus. The results indicated that the NP inhibited biofilm formation and was bactericidal as well. The gauze was doped with NPs, and its wound healing property was evaluated using mice model. Results indicated that the wound healing process was fastened by using the NPs gauze doped with NPs without the administration of antibiotics.


Assuntos
Antibacterianos , Bandagens , Clorexidina/análogos & derivados , Nanopartículas Metálicas/química , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Clorexidina/química , Clorexidina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Prata/química , Prata/farmacologia
8.
J Mater Sci Mater Med ; 30(12): 132, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31786679

RESUMO

The adhesive systems have the function to establish the connection between the restorative material and dental tissue, therefore it is of fundamental importance, because failures in the adhesive interface can reduce the life of a dental restoration. This study investigated the possibility of using the adhesive layer as a chlorhexidine modified release system evaluating their impact on the properties of these systems as well as evaluating the impact of these systems on immediate and post-aging dentin adhesion. Were used a matrix with BisGMA, UDMA, HEMA and TEGDMA copolymer and clay particles (Dellite 67G); associated with a chlorhexidine and a camphorquinone photoinitiator system. The properties of these systems were evaluated by the XRD, FTIR spectrophotometer, flexural strength, elasticity modulus, drug release, enzymatic inhibition and dentin adhesion resistance. The presence of the clay can raise the mechanical properties of the adhesive systems engendering a more resistant hybrid layer and led to a more sustained release of chlorhexidine in the systems, allowing a longer effective period of MMP-2 inhibition. The hypothesis that the addition of clays as release modulators could increase the effectiveness of these drugs in inhibiting the dentin's MPPs and consequently enhancing the adhesive durability was confirmed. These results indicate that the controlled release of chlorhexidine is able to reduce the process of loss of adhesion presenting itself as a promising system to increase the longevity of dental restorations.


Assuntos
Clorexidina/química , Argila/química , Materiais Dentários , Dentina/química , Liberação Controlada de Fármacos , Materiais Biocompatíveis , Preparações de Ação Retardada , Adesivos Dentinários , Teste de Materiais , Resistência à Tração , Fatores de Tempo
9.
Int J Pharm ; 572: 118833, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715363

RESUMO

Different types of in-situ forming implants based on poly(lactic-co-glycolic acid) (PLGA) for the controlled dual release of an antiseptic drug (chlorhexidine) and an anti-inflammatory drug (ibuprofen) were prepared and thoroughly characterized in vitro. N-methyl-pyrrolidone (NMP) was used as water-miscible solvent, acetyltributyl citrate (ATBC) as plasticizer and hydroxypropyl methylcellulose (HPMC) was added to enhance the implants' stickiness/bioadhesion upon formation within the periodontal pocket. Different drug forms exhibiting substantially different solubilities were used: chlorhexidine dihydrochloride and digluconate as well as ibuprofen free acid and lysinate. The initial drug loadings were varied from 1.5 to 16.1%. In vitro drug release, dynamic changes in the pH of the surrounding bulk fluid and in the systems' wet mass as well as polymer degradation were monitored. Importantly, the release of both drugs, chlorhexidine and ibuprofen, could effectively be controlled simultaneously during several weeks. Interestingly, the tremendous differences in the drug forms' solubilities (e.g., factor >5000) did not translate into major differences in the resulting release kinetics. In the case of ibuprofen, this can likely (at least in part) be attributed to significant drug-polymer interactions (ibuprofen acts as a plasticizer for PLGA). In the case of chlorhexidine, the release of the much less soluble dihydrochloride was even faster compared to the more soluble digluconate (when combined with ibuprofen free acid). In the case of ibuprofen, at higher initial drug loadings also limited solubility effects within the implants seem to play a role, in contrast to chlorhexidine. In the latter case, instead, increased system porosity effects likely dominate at higher drug loadings.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Clorexidina/administração & dosagem , Ibuprofeno/administração & dosagem , Adesividade , Anti-Infecciosos Locais/química , Anti-Inflamatórios não Esteroides/química , Química Farmacêutica , Clorexidina/química , Preparações de Ação Retardada , Combinação de Medicamentos , Implantes de Medicamento , Liberação Controlada de Fármacos , Excipientes/química , Ibuprofeno/química , Doenças Periodontais/tratamento farmacológico , Plastificantes/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Porosidade , Solubilidade , Solventes/química
10.
Int J Pharm ; 569: 118564, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31352049

RESUMO

Control of infection and inflammation is crucial for the success of periodontal treatment. In this study, in-situ forming implants (ISFI) loaded with chlorhexidine dihydrochloride (CHX) and ibuprofen (IBU) were developed and tested to optimize periodontal treatment outcomes. Release profiles were promising. Exposure to 1.5% and 5.3% CHX-IBU loaded ISFI's release media decreased significantly the P. gingivalis growth up to 20-fold and 35-fold, respectively, after 48 h (p < 0.05). The metabolic activity assay of gingival epithelial cells (EC) demonstrated 1.5% CHX-IBU-loaded ISFI to be non-toxic, therefore, it was selected for further experimentation. Furthermore, significant down-regulation of TNF-α release (34% at 6 h and 43% at 24 h, p < 0.05) in P. gingivalis lipopolysaccharide (Pg-LPS) stimulated EC exposed to 1.5% CHX-IBU ISFI release medium was demonstrated by ELISA. In vivo, 1.5% CHX-IBU ISFI was injected into the periodontal pocket in an experimental periodontitis mouse model and the reduction in inflammation and improvement in periodontal wound healing was evaluated through inflammatory cell scoring and histomorphometry at 7- and 15-days post-treatment. The results indicate that CHX-IBU loaded ISFI could be efficient as adjuvant to periodontal therapy for the control of infection and inflammation. Moreover, other (e.g., pro-regenerative) drugs could be incorporated into ISFI to further improve periodontal treatment outcomes.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Clorexidina/administração & dosagem , Ibuprofeno/administração & dosagem , Periodontite/tratamento farmacológico , Animais , Anti-Infecciosos Locais/química , Anti-Inflamatórios não Esteroides/química , Linhagem Celular , Clorexidina/química , Implantes de Medicamento , Liberação Controlada de Fármacos , Células Epiteliais/efeitos dos fármacos , Gengiva/citologia , Humanos , Ibuprofeno/química , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Estudo de Prova de Conceito , Cicatrização/efeitos dos fármacos
11.
Gen Dent ; 67(3): 58-61, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31199746

RESUMO

This study evaluated the effect of previous irrigation with chlorhexidine (CHX) on the bond strength of a calcium silicate-based material, Biodentine, when used for furcal repair. Furcal perforations were produced in 30 extracted mandibular molars. Teeth were divided into 3 groups according to the irrigant used: distilled water (DW), CHX followed by DW (CHX), and CHX followed by ethylenediaminetetraacetic acid (EDTA) and DW (CHX/EDTA). Biodentine was used to repair the perforations. A push-out bond strength test was performed after 7 days, and data were statistically analyzed using Kruskal-Wallis and Dunn tests (P < 0.05). The CHX/EDTA group showed significantly lower values than the DW and CHX groups (P < 0.05). The failure mode of the DW group was mainly mixed, while that of the CHX group was cohesive. The CHX/EDTA group exhibited adhesive and mixed failures. Irrigation with CHX prior to furcation repair did not result in a statistically significant difference, compared to the use of DW, in the push-out bond strength of Biodentine.


Assuntos
Compostos de Cálcio/química , Clorexidina/química , Colagem Dentária , Materiais Restauradores do Canal Radicular , Silicatos/química , Cálcio , Análise do Estresse Dentário , Dentina , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio
12.
Biomed Mater Eng ; 30(3): 279-285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30988236

RESUMO

The objective of this study was to evaluate the effect of sodium hypochlorite and chlorhexidine solutions and their inactivating agents on the push-out bond strength of mineral trioxide aggregate (MTA). One hundred fifty root slices were prepared and their root canal spaces were enlarged using diamond burs. MTA was prepared and compacted to root canal spaces. The samples were randomly separated to 4 groups that would be immersed into the selected solutions (5.25% sodium hypochlorite (NaOCl), 5.25% NaOCl and sodium thiosulfate, 2% chlorhexidine (CHX), 2% CHX and a mixture of Tween 80 and 0.3% L-alfa-lecithin) and a control group (n = 30). Push-out bond strength of each specimen was tested with universal testing machine. The data was analyzed by one-way analysis of variance and Tukey tests. There were no significant differences between the push-out bond strength values of the irrigation groups and the control group. A significant difference was found between the push-out bond strength values of NaOCl-Sodium thiosulfate and CHX-L-alpha-lecithin groups. Contact with NaOCl and its neutralizing agent with MTA after 10 minutes of setting period increased the push-out bond strength of MTA. On the other hand, any contact with CHX alone or with subsequent application using L-alfa-lecithin should be avoided since that might decrease the push-out bond strength of freshly mixed MTA.


Assuntos
Compostos de Alumínio/química , Compostos de Cálcio/química , Clorexidina/química , Materiais Dentários/química , Óxidos/química , Irrigantes do Canal Radicular/química , Silicatos/química , Hipoclorito de Sódio/química , Análise do Estresse Dentário/instrumentação , Combinação de Medicamentos , Desenho de Equipamento , Humanos , Lecitinas/química , Teste de Materiais/instrumentação , Polissorbatos/química , Irrigação Terapêutica
13.
Dokl Biochem Biophys ; 484(1): 48-51, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31012012

RESUMO

To select the optimum method for disinfecting scaffolds before recellularization, the effects of octenisept and chlorhexidine at different concentrations on lung biological matrices before and after decellularization were studied by using morphological methods (studies of biomechanical strength of extracellular matrix fibers) and by analyzing chemiluminescence in rats. Chlorhexidine diluted 1 : 10 had the least damage on the matrix properties and to the greatest extent contributed to disinfection of scaffolds for their further storage and experimental studies.


Assuntos
Anti-Infecciosos Locais/química , Clorexidina/química , Desinfecção/métodos , Matriz Extracelular/química , Pulmão/química , Animais , Ratos
14.
Braz Oral Res ; 33: e005, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30758405

RESUMO

The objective of this study was to assess the influence of chlorhexidine (liquid and gel) and zinc oxide in calcium hydroxide (CH) pastes on root pH in simulated external resorption. One hundred human anterior teeth with a single root canal were selected. After decoronation and root canal instrumentation, the specimens were divided into 4 experimental groups and 1 control group (without intracanal paste): CH + saline (CH+S), CH + 2% chlorhexidine liquid (CH+ CHX), CH + 2% chlorhexidine gel (CH+ CHXg), and CH + 2% chlorhexidine gel + zinc oxide (CH+ CHXg+ZnO). pH was measured using a microelectrode at 3 and 24 h, and 1, 2, 3, and 4 weeks after inserting intracanal pastes. Data were analyzed statistically using an ANOVA and Tukey's test (p < 0.05). The CH+CHXg+ZnO group had the highest pH values throughout (p<0.05). The CH+S and CH+ CHX groups had the highest pH values after 1 week and the CH+ CHXg group after 2 weeks. CH+ CHXg maintained the highest pH until the fourth week compared with CH+ CHX (p < 0.05). The control group remained at a neutral pH at all evaluated times. It can be concluded that chlorhexidine solution or gel maintained the alkaline pH of CH, and chlorhexidine gel allowed a slower decrease in pH over time. CH+ CHXg+ZnO showed the highest pH values and was an effective intracanal medication for maintaining alkaline root pH in the area of resorption.


Assuntos
Hidróxido de Cálcio/química , Clorexidina/química , Irrigantes do Canal Radicular/química , Raiz Dentária/efeitos dos fármacos , Óxido de Zinco/química , Análise de Variância , Géis , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Pomadas , Valores de Referência , Reprodutibilidade dos Testes , Reabsorção da Raiz/tratamento farmacológico , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo
15.
J Pharm Biomed Anal ; 164: 360-364, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30439663

RESUMO

Accurate knowledge of the safety of the combined use of hyper-pure chlorine dioxide (ClO2, Solumium) with different endodontic agents is not known. The objective was to investigate the possible interactions between hyper-pure ClO2 and Chlorhexidine digluconate (CHX) as well as hyper-pure ClO2 and ethylenediaminetetraacetic acid (EDTA) in vitro. High-performance liquid chromatography (HPLC) was used to analyse the reaction between ClO2 and CHX for studying the possible increase of para-chloroaniline (PCA). Nuclear magnetic resonance (NMR) method was applied to investigate if the oxidising property of ClO2 inactivates EDTA. CHX itself may contain PCA; however, its amount did not increase after the mixing up with ClO2. While ClO2 did not oxidise PCA, on the other hand, it oxidised EDTA into numerous degradation products, but this reaction was slow. Hyper-pure ClO2 of excellent antimicrobial properties should be considered as a safe alternative endodontic disinfectant agent in combinations or as a final rinse. The lack of chemical interaction between ClO2 and CHX confirms their safe application in combination.


Assuntos
Anti-Infecciosos Locais/química , Clorexidina/análogos & derivados , Compostos Clorados/química , Desinfetantes de Equipamento Odontológico/química , Ácido Edético/química , Óxidos/química , Anti-Infecciosos Locais/efeitos adversos , Anti-Infecciosos Locais/farmacologia , Clorexidina/efeitos adversos , Clorexidina/química , Compostos Clorados/efeitos adversos , Compostos Clorados/farmacologia , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Desinfetantes de Equipamento Odontológico/efeitos adversos , Desinfetantes de Equipamento Odontológico/farmacologia , Cavidade Pulpar/efeitos dos fármacos , Desinfecção/métodos , Combinação de Medicamentos , Interações Medicamentosas , Ácido Edético/efeitos adversos , Humanos , Oxirredução , Óxidos/efeitos adversos , Óxidos/farmacologia , Espectroscopia de Prótons por Ressonância Magnética/métodos
16.
Colloids Surf B Biointerfaces ; 174: 224-231, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30465997

RESUMO

This study synthesized and characterized a chlorhexidine (CHX)-carrier nanosystem based on iron oxide magnetic nanoparticles (IONPs) and chitosan (CS), and evaluated its antimicrobial effect on mono- and dual-species biofilms of Candida albicans and Streptococcus mutans. CHX was directly solubilized in CS-coated IONPs and maintained under magnetic stirring for obtaining the IONPs-CS-CHX nanosystem. Antimicrobial susceptibility testing for planktonic cells was performed by determining the minimum inhibitory concentration (MIC) of the nanosystem and controls. The effects of the IONPs-CS-CHX nanosystem on the formation of mono- and dual-species biofilms, as well as on pre-formed biofilms were assessed by quantification of total biomass, metabolic activity and colony-forming units. Data were analyzed by the Kruskal-Wallis' test or one-way analysis of variance, followed by the Student-Newman-Keuls' or Holm-Sidak's tests (α = 0.05), respectively. Physico-chemical results confirmed the formation of a nanosystem with a size smaller than 40 nm. The IONPs-CS-CHX nanosystem and free CHX showed similar MIC values for both species analyzed. In general, biofilm quantification assays revealed that the CHX nanosystem at 78 µg/mL promoted similar or superior antibiofilm effects compared to its counterpart at 39 µg/mL and free CHX at 78 µg/mL. These findings highlight the potential of CS-coated IONPs as preventive or therapeutic agents carrying CHX to fight biofilm-associated oral diseases.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Quitosana/química , Clorexidina/farmacologia , Óxido Ferroso-Férrico/química , Nanopartículas/química , Streptococcus mutans/efeitos dos fármacos , Antibacterianos/química , Clorexidina/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície
17.
Arch Oral Biol ; 98: 164-175, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30500666

RESUMO

This study identified potential inhibitory compounds of the phosphoenolpyruvate-sugar. Phosphotransferase system of S. mutans, specifically enzyme II mannose transporter (EIIMan) in its subunits IIA, IIB and IIC by means of a selection protocol and in silico molecular analysis. Intervening the phosphotransferase system would compromise the physiological behavior and the pathogenic expression of S. mutans, and possibly other acidogenic bacteria that use phosphotransferases in their metabolism-making the phosphotransferase system a therapeutic target for the selective control of acidogenic microorganisms in caries control. Several computational techniques were used to evaluate molecular, physicochemical, and toxicological aspects of various compounds. Molecular docking was used to calculate the binding potential (ΔG) between receptor protein subunits and more than 836,000 different chemical compounds from the ZINC database. Physicochemical parameters related to the compounds' pharmacokinetic and pharmacodynamic indicators were evaluated, including absorption, distribution, metabolism, excretion, and toxicity (ADMET), and chemical analysis characterized the compounds structures. Thirteen compounds with EII binding potential of the phosphotransferase system of S. mutans and favorable ADMET properties were identified. Six spirooxindoles and three pyrrolidones stand out from the found compounds; unique structural characteristics of spirooxindoles and pyrrolidones associated with various reported biological activities like anti-microbial, antiinflammatory, anticancer, nootropic, neuroprotective and antiepileptic effects, among other pharmacological effects with surprising differences in terms of mechanisms of action. Following studies will provide more evidence of the action of these compounds on the phosphotransferase system of S. mutans, and its possible applications.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Simulação de Acoplamento Molecular/métodos , Fosfotransferases/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Clorexidina/química , Clorexidina/farmacologia , Bases de Dados de Produtos Farmacêuticos , Cárie Dentária/prevenção & controle , Descoberta de Drogas/métodos , Terapia de Alvo Molecular/métodos , Farmacocinética , Fosfoenolpiruvato , Estrutura Terciária de Proteína , Pirrolidinas/química , Pirrolidinas/farmacologia , Pirrolidinonas/química , Pirrolidinonas/farmacologia , Análise de Sequência de Proteína , Software , Streptococcus mutans/enzimologia
18.
Drug Dev Ind Pharm ; 45(2): 314-322, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30372644

RESUMO

OBJECTIVE: The objective was to evaluate the influencing factors in the fabrication of gelatin matrix (gelatin chips) for drug delivery. The attributes affecting drug release characteristics of the gelatin products were examined. SIGNIFICANCE: Understanding the attributes that affect drug release from gelatin matrix could provide the knowledge base for the development, manufacturing, and performance evaluation of gelatin-based drug products for sustained drug delivery. METHODS: Chlorhexidine (CHX) was the model drug in the gelatin-product testing. The gelatin products were fabricated by two methods: a single-pot mixing of all the components and a two-step gelatin crosslinking followed by drug loading. Different gelatin types (Type A porcine and Type B bovine), glutaraldehyde (GTA) crosslinking conditions, glycerin concentration, and CHX concentration in drug loading and loading time were used to fabricate the products. The cumulative amounts of CHX release from the gelatin products were determined using in vitro release testing (IVRT). RESULTS: The attributes affecting CHX release from the gelatin products were gelatin type, GTA crosslinking, and CHX loading concentration. The fabrication methods (two-step method of gelatin crosslinking and drug loading by equilibration vs. direct mixing of the components) also affected CHX release. Other attributes such as glycerin and CHX loading time did not show significant effects on drug release under the conditions studied. In addition, the results in the two IVRT methods employed in this study were comparable. CONCLUSION: Gelatin products of qualitative (Q1) and quantitative (Q2) differences could lead to different drug release behaviors. Drug release was also affected by the ingredient mixing steps during gelatin chip fabrication.


Assuntos
Clorexidina/administração & dosagem , Clorexidina/química , Desinfetantes/administração & dosagem , Desinfetantes/química , Gelatina/química , Animais , Bovinos , Reagentes para Ligações Cruzadas , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Excipientes , Glutaral/química , Glicerol/química , Suínos
19.
J Prosthodont ; 28(2): e869-e872, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29520956

RESUMO

PURPOSE: To evaluate the effect of chemical disinfection on the color stability of room temperature vulcanizing (RTV) maxillofacial silicone elastomer with and without pigment addition. MATERIALS AND METHODS: Sixty specimens were obtained from a RTV maxillofacial silicone. The specimens were randomly divided into 6 groups according to pigments and disinfectant to be used (n = 10). NP-DW-nonpigmented silicone specimens to be immersed in distilled water (control). NP-S- nonpigmented silicone specimens to be rubbed with an anti-bacterial soap. NP-CHX-nonpigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). P-DW-pigmented silicone specimens to be immersed in distilled water (control). P-S-pigmented silicone specimens to be rubbed with antibacterial soap. P-CHX-pigmented silicone specimens to be immersed in chlorhexidine gluconate solution (2%). Disinfection was conducted 6 times a day for 60 days simulating 1 year of usage. Color was evaluated after 60 days (disinfection period) using a reflectance spectrophotometer. Color alterations were calculated by the CIE L∗ a∗ b∗ system. Data were analyzed by t-test, one-way ANOVA, and Tukey test (α = 0.05). RESULTS: NP-S and P-S exhibited the highest color alterations, whereas NP-DW and P-DW the lowest color alterations. CONCLUSION: Disinfection procedures affect the color stability of maxillofacial silicone. Chlorhexidine gluconate solution (2%) can be effectively used as a chemical disinfectant for maxillofacial prostheses. Antibacterial soap produced clinically unacceptable color changes in the silicone, hence is not advisable as a disinfectant.


Assuntos
Desinfetantes/química , Prótese Maxilofacial , Elastômeros de Silicone/química , Clorexidina/análogos & derivados , Clorexidina/química , Cor , Técnicas In Vitro , Teste de Materiais , Sabões/química , Propriedades de Superfície
20.
Pharm Dev Technol ; 24(4): 402-409, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30265590

RESUMO

In this study, chlorhexidine-loaded poly(ε-caprolactone) nanospheres (CHX-NS) were prepared and successfully coated on the urinary catheters. Properties of CHX-NS were evaluated including drug loading content and the nanosphere size. Effects of different lyoprotectants for long-term storage of CHX-NS were also investigated. In vitro release study and antibacterial activity were also conducted using 20 cycles coated-urinary catheters. Results showed that the high-pressure emulsification-solvent evaporation technique provided the drug loading content at 1.14 ± 0.16% and the size of nanospheres was 152 ± 37 nm. The suitable lyoprotectant for long-term storage of CHX-NS was sucrose which provided noticeably no aggregation at the degree of reconstitution at 89.95%. The amount of CHX loading on coated catheters was at 4.55 ± 0.31 mg. Drug release from the coated catheters in artificial urine could be prolonged up to 2 weeks and bacteria proliferation was inhibited up to 14 days. These results suggest that the antimicrobial activity of CHX-NS reduces the adherence of the uropathogens to the catheter surface. Chlorhexidine-loaded polymeric nanospheres were fabricated which can be successfully coated on urinary catheters. These systems have potential use for prolonged antimicrobial applications.


Assuntos
Antibacterianos/química , Anti-Infecciosos Locais/química , Caproatos/química , Clorexidina/química , Lactonas/química , Nanosferas/química , Cateteres Urinários , Antibacterianos/administração & dosagem , Anti-Infecciosos Locais/administração & dosagem , Caproatos/administração & dosagem , Clorexidina/administração & dosagem , Avaliação Pré-Clínica de Medicamentos/métodos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Liofilização/métodos , Lactonas/administração & dosagem , Testes de Sensibilidade Microbiana/métodos , Nanosferas/administração & dosagem , Cateteres Urinários/microbiologia
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