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1.
Braz Oral Res ; 33: e060, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365705

RESUMO

This study evaluated the effect of hypertension on tissue response and biomineralization capacity of white Mineral Trioxide Aggregate (MTA), High-plasticity MTA (MTA HP), and Biodentine® (BDT) in rats. Polyethylene tubes filled with MTA, MTA HP, BDT, and the control group (empty tubes) were placed into the dorsal subcutaneous tissue of 32 male rats (16 normotensive (NT) and 16 hypertensive rats - 8 per group). After 7 and 30 days, the polyethylene tubes surrounded by connective tissue were removed, fixed, and embedded in histological resin. The mean number of inflammatory cells was estimated in HE-stained sections, biomineralization was quantified as area (µm2) by Kossa (VK) staining, and examination by polarized light (LP) microscopy was performed. The differences amongst the groups were analyzed statistically by the Mann-Whitney or Student's t test, according to Shapiro-Wilk test of normality (p < 0.05). The inflammatory responses to all materials were greater in hypertensive rats than in NT rats (p < 0.05). Positive VK staining in MTA and BDT were more pronounced in NT rats at 7 and 30 days (p < 0.05). Birefringent structures in LP for MTA, MTA HP, and BDT were more pronounced in NT rats at 7 days (p<0.05). In rats, hypertension was able to increase inflammatory infiltrate and decrease biomineralization of the tested materials.


Assuntos
Compostos de Alumínio/farmacologia , Materiais Biocompatíveis/farmacologia , Biomineralização/fisiologia , Compostos de Cálcio/farmacologia , Hipertensão/fisiopatologia , Óxidos/farmacologia , Silicatos/farmacologia , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/fisiopatologia , Animais , Combinação de Medicamentos , Hipertensão/complicações , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Teste de Materiais , Microscopia de Polarização , Ratos Wistar , Reprodutibilidade dos Testes , Tela Subcutânea/patologia , Fatores de Tempo
2.
J Appl Oral Sci ; 27: e20180550, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365709

RESUMO

PURPOSE: To compare, both qualitatively and quantitatively, the inflammatory cells, vascular density and IL-6 immunolabeled cells present in the pulp after pulpotomy with white MTA versus 15.5% ferric sulfate (FS). METHODOLOGY: Forty-eight mandibular first molars from 24 Wistar rats were divided into MTA or FS groups and subdivided according to the period after pulpotomy procedure (24, 48 and 72 hours). Four teeth (sound and untreated) were used as controls. Histological sections were obtained and assessed through the descriptive analysis of morphological aspects of pulp tissue and the quantification of inflammatory cells, vascular density and interleukin-6 (IL-6) expression. Data were statistically analyzed (p<0.05). RESULTS: The number of inflammatory cells was similar in both groups, being predominantly localized at the cervical radicular third. In the MTA group, increased inflammation was observed at 48 hours. Vascular density was similar in both groups and over time, being predominant in the medium radicular third. No correlation was found between the number of inflammatory cells and the vascular density. Pulp tissue was more organized in MTA-treated teeth. In both groups, a weak to moderate IL-6 expression was detected in odontoblasts and inflammatory cells. Comparing both groups, there was a greater IL-6 expression in the cervical radicular third of teeth treated with MTA at 24 hours and in the medium and apical thirds at 72 hours, while in the FS group a greater IL-6 expression was found in the apical third at 24 hours. CONCLUSION: The MTA group presented better histological features and greater IL-6 expression than the FS group. However, no difference was observed between the groups regarding the inflammatory status and vascularization, suggesting the usefulness of FS as a low-cost alternative to MTA.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Compostos Férricos/farmacologia , Inflamação/imunologia , Interleucina-6/análise , Óxidos/farmacologia , Pulpotomia/efeitos adversos , Silicatos/farmacologia , Animais , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/patologia , Combinação de Medicamentos , Masculino , Ratos Wistar , Estatísticas não Paramétricas , Fatores de Tempo
4.
Talanta ; 202: 591-599, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171226

RESUMO

Photodynamic therapy (PDT) was considered as an effective treatment. Whereas only PDT is not enough to achieve effective therapy on account of irradiation intensity decreases as depth increases as well as tumor hypoxia. Combination with gene therapy and photodynamic therapy have emerged as an effective strategy to improve therapeutic effectiveness. In the present study, a GSH responsive MnO2 was employed to delivery TB and DNAzyme for cancer imaging and PDT-gene combination treatment. TB, a photosensiters with aggregation-induced emission characteristic, was employed for photodynamic therapy, while DNAzyme, acting as catalysts for the degradation of EGR-1 mRNA, was exploited for gene silencing. All of the results of tumor treatment in vitro have implied that MnO2-DNAzyme-TB nanocomposite (MDT) can internalize into cells. Subsequently, MDT could decrease the expression of EGR-1 by gene silencing that enabling inhibition of cell growth. In addition, the singlet oxygen which was generated by the aggregated TB were able to further suppress cell growth. Combination therapy of photodynamic as well as gene therapy greatly enhanced antitumor efficiencies. Furthermore, in vivo tumor treatment experiments demonstrated that MDT under illumination can effectively inhibit the tumor growth of MCF-7 tumor-bearing mice by photodynamic and gene silencing combination therapy.


Assuntos
Antineoplásicos/farmacologia , DNA Catalítico/metabolismo , Terapia Genética , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA Catalítico/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Proteína 1 de Resposta de Crescimento Precoce/antagonistas & inibidores , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Compostos de Manganês/síntese química , Compostos de Manganês/química , Camundongos , Camundongos Nus , Nanocompostos , Imagem Óptica , Óxidos/síntese química , Óxidos/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , Relação Estrutura-Atividade , Propriedades de Superfície
5.
Int J Mol Sci ; 20(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072046

RESUMO

Chronic kidney disease (CKD) is characterized by an oxidative stress status, driving some CKD-associated complications, even at the gastrointestinal level. Indoxyl Sulfate (IS) is a protein-bound uremic toxin, poorly eliminated by dialysis. This toxin is able to affect the intestinal system, but its molecular mechanism/s in intestinal epithelial cells (IECs) remain poorly understood. This study's aim was to evaluate the effect of IS (31.2-250 µM) on oxidative stress in IEC-6 cells and on the intactness of IECs monolayers. Our results indicated that IS enhanced oxidative cell damage by inducing reactive oxygen species (ROS) release, reducing the antioxidant response and affecting Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) nuclear translocation as well its related antioxidant enzymes. In the wound healing assay model, IS reduced IEC-6 migration, slightly impaired actin cytoskeleton rearrangement; this effect was associated with connexin 43 alteration. Moreover, we reported the effect of CKD patients' sera in IEC-6 cells. Our results indicated that patient sera induced ROS release in IEC-6 cells directly related to IS sera content and this effect was reduced by AST-120 serum treatment. Results highlighted the effect of IS in inducing oxidative stress in IECs and in impairing the intactness of the IECs cell monolayer, thus significantly contributing to CKD-associated intestinal alterations.


Assuntos
Antioxidantes/farmacologia , Indicã/farmacologia , Intestinos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Insuficiência Renal Crônica/tratamento farmacológico , Animais , Carbono/farmacologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Conexina 43/genética , Células Epiteliais/efeitos dos fármacos , Humanos , Intestinos/patologia , Fator 2 Relacionado a NF-E2/genética , Óxidos/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Uremia/tratamento farmacológico , Uremia/metabolismo , Uremia/patologia
6.
Ren Fail ; 41(1): 284-293, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31014150

RESUMO

OBJECTIVE: We investigate the mechanism of neutrophil/lymphocyte ratio (NLR) elevation, a useful prognostic marker in patients with cardiovascular diseases (CVDs). METHODS: In this clinical study, we retrospectively searched for factors associated with NLR elevation in cardiovascular outpatients. In animal experiments using mice with adenine-induced nephropathy, we further examined the hematopoietic process in bone marrow and explored the mechanism of NLR elevation. RESULT: In patients with CVDs or their risk factors, multiple regression analysis revealed that decrease in estimated glemerular filtration rate and increase in white blood cell count were significantly associated with increase in NLR. In mice with adenine-induced nephropathy, NLR and serum indoxyl sulfate (IS) levels were increased. Fluorescence-activated cell sorting revealed the increase in the number of myeloid progenitors and decrease in the number of common lymphoid progenitors, suggesting biased granulocyte side in the hematopoietic process in bone marrow. Treatment with oral charcoal adsorbent AST-120 decreased serum concentration of IS and normalized NLR and bone marrow abnormalities in mice with adenine-induced nephropathy. CONCLUSION: Renal function was a strong determinant of NLR in cardiovascular outpatients. NLR elevation due to renal impairment is caused by distortion of the hematopoietic process in bone marrow. IS plays a significant role in these processes.


Assuntos
Doenças Cardiovasculares/etiologia , Nefropatias/complicações , Linfócitos , Neutrófilos , Adenina/toxicidade , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/sangue , Medula Óssea/patologia , Carbono/farmacologia , Carbono/uso terapêutico , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/prevenção & controle , Modelos Animais de Doenças , Feminino , Taxa de Filtração Glomerular , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Humanos , Indicã/sangue , Indicã/metabolismo , Nefropatias/sangue , Nefropatias/induzido quimicamente , Nefropatias/fisiopatologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Óxidos/farmacologia , Óxidos/uso terapêutico , Prognóstico , Estudos Retrospectivos , Fatores de Risco
7.
ACS Appl Mater Interfaces ; 11(16): 15014-15027, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30933472

RESUMO

A bacterial infection on the surface of medical apparatus and instruments as well as artificial implants is threatening human health greatly. Antibiotics and traditional bacterial-killing agents, even silver nanoparticles, can induce bacterial resistance during long-term interaction with bacteria. Hence, rapid surface sterilization and prevention of bacterial infection in the long term are urgent for biomedical devices, especially for artificial implant materials. Herein, a hybridized chitosan (CS), silver nanoparticles (AgNPs), and MnO2 nanosheets coating was designed on the surface of titanium plates, which can ensure the implants a rapid and highly effective antibacterial efficacy of 99.00% against Staphylococcus aureus ( S. aureus) and 99.25% against Escherichia coli ( E. coli) within 20 min of 808 nm near-infrared light (NIR) irradiation. The exogenous NIR irradiation can trigger the MnO2 nanosheets to produce enough hyperthermia within 10 min, which can combine with a low concentration of prereleased Ag+ from the coating to achieve superior antimicrobial efficacy through synergistic effects. In contrast, either prereleased Ag ions or a photothermal effect alone can achieve much lower antibacterial efficiency under the same concentration, i.e., 24.00% and 30.01% for the former and 30.00% and 42.54% for the later toward S. aureus and E. coli, respectively. The possible cytotoxicity of coatings could be eliminated owing to the low concentration of AgNPs and chitosan encapsulation. Thus, the novel bifunctional coating Ag/CS@MnO2 can exhibit great potential in deep site disinfection of Ti implants through the synergy of prereleased Ag ions and a photothermal effect within a short time.


Assuntos
Quitosana , Materiais Revestidos Biocompatíveis , Desinfecção , Escherichia coli/crescimento & desenvolvimento , Raios Infravermelhos , Compostos de Manganês , Nanopartículas/química , Óxidos , Prata , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Camundongos , Células NIH 3T3 , Óxidos/química , Óxidos/farmacologia , Prata/química , Prata/farmacologia
8.
J Nanobiotechnology ; 17(1): 54, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30992018

RESUMO

BACKGROUND: Nanomaterials that exhibit intrinsic enzyme-like characteristics have shown great promise as potential antibacterial agents. However, many of them exhibit inefficient antibacterial activity and biosafety problems that limit their usefulness. The development of new nanomaterials with good biocompatibility and rapid bactericidal effects is therefore highly desirable. Here, we show a new type of terbium oxide nanoparticles (Tb4O7 NPs) with intrinsic oxidase-like activity for in vitro and in vivo antibacterial application. RESULTS: We find that Tb4O7 NPs can quickly oxidize a series of organic substrates in the absence of hydrogen peroxide. The oxidase-like capacity of Tb4O7 NPs allows these NPs to consume antioxidant biomolecules and generate reactive oxygen species to disable bacteria in vitro. Moreover, the in vivo experiments showed that Tb4O7 NPs are efficacious in wound-healing and are protective of normal tissues. CONCLUSIONS: Our results reveal that Tb4O7 NPs have intrinsic oxidase-like activity and show effective antibacterial ability both in vitro and in vivo. These findings demonstrate that Tb4O7 NPs are effective antibacterial agents and may have a potential application in wound healing.


Assuntos
Antibacterianos/química , Escherichia coli , Nanopartículas Metálicas/química , Óxidos/química , Oxirredutases/química , Staphylococcus aureus , Térbio/química , Cicatrização , Animais , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Sobrevivência Celular , Escherichia coli/efeitos dos fármacos , Hemólise , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos Endogâmicos BALB C , Óxidos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Térbio/farmacologia
9.
J Appl Microbiol ; 127(2): 370-378, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31009147

RESUMO

AIMS: A major drawback of using dairy slurry as fertilizer is that it may contains pathogens such as Mycobacterium avium subsp. paratuberculosis (MAP), and it could represent a risk to animal and public health. Thus, the aim of this study was to evaluate the fate of MAP and bacterial communities in dairy slurry after chemical treatments. METHODS AND RESULTS: Cattle slurry, naturally contaminated with MAP, was collected from a dairy herd and divided into 32 glass bottles which were assigned to eight different treatments (control, 3·0% CaO, 0·5% NaOH; 0·087%, 0·11% and 0·14% H2 SO4 ; and 1·0 and 2·5% KMnO4 ). Treated dairy slurry samples were evaluated at 0, 1, 3, 7, 15, 30 and 60-days following treatment application for viable MAP and dairy slurry pH, and in addition temperature in this material was monitored continuously. Bacterial counts were estimated at each sampling time. A Bayesian zero-inflated Poisson mixed model was fitted to assess the effect of each treatment on the count of MAP cells. Model results indicated that only the 3·0% CaO treatment had a statistically important negative effect on MAP counts during the study period. For most treatments, MAP was undetectable immediately after chemical treatment but re-appeared over time, in some replicates at low concentrations. However, in those cases MAP counts were not statistically different than the control treatment. Regarding the fate of the other bacterial populations, the Firmicutes phylum was the dominant population in the un-treated slurry while Clostridia class members were among the most prevalent bacteria after the application of most chemical treatments. CONCLUSION: Only 3% CaO treatment had a statistically important negative effect on MAP viability in cattle slurry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence of MAP partial control in dairy slurry. This information should be considered as a best management practice to reduce MAP and other pathogens for slurry management on dairy farms.


Assuntos
Antibacterianos/farmacologia , Indústria de Laticínios , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Animais , Teorema de Bayes , Compostos de Cálcio/farmacologia , Bovinos , Feminino , Fertilizantes , Esterco/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Óxidos/farmacologia
10.
Mater Sci Eng C Mater Biol Appl ; 101: 674-685, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029361

RESUMO

In the present study, efficient adsorptive removal of fluoride and Direct Blue 53 (DB-53) dye solution on perovskite lanthanum aluminate (PLA) has been investigated. To characterize the prepared PLA with analytical techniques like FTIR, SEM, EDS, PXRD, PHZPC and BET. The influence of adsorbent dose (0.05-0.6) gL-1, pH (2-12), contact time (0-60 min) and initial adsorbate concentration (0-50 mg L-1) were studied on adsorption process. Mathematical modeling of kinetics and isotherms were computed using equations. The pseudo-second-order kinetic and Halsey isotherm equilibrium model are best fitted with experimentally computed data with R2 > 0.96. The value of free mean energy EDR per adsorbate molecule was 1.77 kJmol-1 (fluoride) and 1.86 kJmol-1 (DB-53) with an adsorption capacity 25.103 and 38.03 respectively, hence nature of adsorption suggested as physisorption process. The maximum Langmuir adsorption capacity of PLA was investigated to be 40.8 mgg-1 (fluoride) and 71.4 mgg-1 (DB-53). Present study PLA deficits efficient adsorbent for fluoride and DB-53 dye for ground and industrial wastewater. Further, the effect of in-vitro antimicrobial studies was carried out against six test microorganisms. PLA showed, a maximum antibacterial effect at MIC 63 µg mL-1 for Gram-negative bacteria: Pseudomonas aeruginosa (NCIM 5029) due to the interaction between the positively charged nanoparticle and negatively charged cell wall.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Compostos de Cálcio/farmacologia , Fluoretos/química , Óxidos/farmacologia , Titânio/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Compostos de Cálcio/química , Bactérias Gram-Negativas/efeitos dos fármacos , Cinética , Lantânio , Óxidos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Titânio/química
11.
Mater Sci Eng C Mater Biol Appl ; 98: 1122-1132, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30812996

RESUMO

The multifunctional biological active material design for bone tissue engineering is essential to induce osteoblast cell proliferation and attachment. Adhesion of bacteria on biomaterials to produce biofilms can be major contributors to the pathogenesis of implant material associated infections. This research work focuses on NPF& NBF elemental doping and functionalization of reduced graphene oxide using an imidazolium-based ionic liquid such as BMIM PF6 and BMIM BF4 by hydrothermal method. The resulting tri doped reduced graphene oxide (NPF-rGO and NBF-rGO) composite was further used as a scaffold for bone tissue engineering and anti-biofilm activities. The observation of the effect of NPF-rGO and NBF-rGO on the morphology, adhesion and cell proliferation of HOS cell was investigated. Moreover, the tri doped composite tested its antibiofilm properties against B. subtilis, E. coli, K. pneumoniae, and P. aeruginosa pathogenic bacteria. In-vitro studies clearly show the effectiveness of N, P, B, and F doping promoting the rGO mineralization, biocompatibility, and destruction of bacterial biofilm formation. The result of this study suggests that NPF-rGO and NBF-rGO hybrid material will be a promising scaffold for bone reaeration and implantation with a minimal bacterial infection.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Grafite/química , Grafite/farmacologia , Líquidos Iônicos/química , Equipamentos Ortopédicos/microbiologia , Óxidos/química , Óxidos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Líquidos Iônicos/farmacologia , Íons/química , Osteoblastos/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Engenharia Tecidual/métodos
12.
Food Microbiol ; 81: 108-114, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30910081

RESUMO

Fungi are able to grow on diverse food products and contribute to food spoilage worldwide causing food loss. Consumers prefer freshly squeezed fruit juices, however, the shelf life of these juices is limited due to outgrowth of yeast and fungi. The shelf life of pulsed electric field (PEF) treated juice can be extended from 8 days up to a few weeks before spoilage by moulds becomes apparent. Conidia produced by three Penicillium ssp. (Penicillium expansum, Penicillium buchwaldii and Penicillium bialowiezense), previously isolated from spoiled PEF treated fruit juice and smoothie, were characterized for resistance towards selected mild physical processing techniques in orange juice and toward sanitizers on surfaces. The results show that Penicillium spp. conidia are susceptible to mild heat, high pressure pasteurization (HPP), PEF, cold atmospheric plasma (CAP), UV, and chemical sanitizers chlorine dioxide and hypochlorite albeit with different susceptibility. Treatment with mild heat, HPP, PEF, or chlorine dioxide reduced conidia by more than 5 log. For hypochlorite, UV, and CAP the reduction was between 1 and 3 log. Together, this study provides data for the development of intervention strategies to eliminate spoilage mould conidia in fruit juices.


Assuntos
Desinfecção/métodos , Conservação de Alimentos/métodos , Sucos de Frutas e Vegetais/microbiologia , Penicillium/efeitos dos fármacos , Penicillium/efeitos da radiação , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/efeitos da radiação , Compostos Clorados/farmacologia , Citrus sinensis , Eletricidade , Manipulação de Alimentos , Armazenamento de Alimentos , Temperatura Alta , Ácido Hipocloroso/farmacologia , Testes de Sensibilidade Microbiana , Óxidos/farmacologia , Pasteurização/métodos , Penicillium/crescimento & desenvolvimento , Penicillium/isolamento & purificação , Gases em Plasma/farmacologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação , Raios Ultravioleta
13.
Braz Oral Res ; 33: e010, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30892409

RESUMO

This in situ study aimed to evaluate the antibacterial and anti-demineralization effects of an experimental orthodontic adhesive containing triazine and niobium phosphate bioglass (TAT) around brackets bonded to enamel surfaces. Sixteen volunteers were selected to use intra-oral devices with six metallic brackets bonded to enamel blocks. The experimental orthodontic adhesives were composed by 75% BisGMA and 25% TEGDMA containing 0% TAT and 20% TAT. Transbond XT adhesive (TXT) was used as a control group. Ten volunteers, mean age of 29 years, were included in the study. The six blocks of each volunteer were detached from the appliance after 7 and 14 days to evaluate mineral loss and bacterial growth including total bacteria, total Streptococci, Streptococci mutans, and Lactobacilli. Statistical analysis was performed using GLM model - univariate analysis of variance for microhardness and 2-way ANOVA for bacterial growth (p<0.05). The 20% TAT adhesive caused no difference between distances from bracket and the sound zone at 10-µm deep after 7 and 14 days. After 14 days, higher mineral loss was shown around brackets at 10- to 30-µm deep for TXT and 0% TAT adhesives compared to 20% TAT. S. mutans growth was inhibited by 20% TAT adhesive at 14 days. Adhesive with 20% TAT showed lower S. mutans and total Streptococci growth than 0% TAT and TXT adhesives. The findings of this study show that the adhesive incorporated by triazine and niobium phosphate bioglass had an anti-demineralization effect while inhibiting S. mutans and total Streptococci growth. The use of this product may inhibit mineral loss of enamel, preventing the formation of white spot lesions.


Assuntos
Antibacterianos/farmacologia , Cimentos Dentários/farmacologia , Lactobacillus/efeitos dos fármacos , Nióbio/farmacologia , Óxidos/farmacologia , Fosfatos/farmacologia , Streptococcus/efeitos dos fármacos , Desmineralização do Dente/prevenção & controle , Adulto , Antibacterianos/química , Cerâmica/química , Cerâmica/farmacologia , Cimentos Dentários/química , Método Duplo-Cego , Feminino , Humanos , Masculino , Adulto Jovem
14.
Indian J Dent Res ; 30(1): 31-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900653

RESUMO

Context: It is important to develop new therapeutic materials that have requisite clinical actions, are safe and economical. Aims: This study aims to histologically evaluate curcumin, an extract of turmeric (Curcuma longa) as a pulpotomy agent in rat molars and to compare it to mineral trioxide aggregate (MTA). Settings and Design: Animal study. Subjects and Methods: Twelve Wistar-Albino rats were randomly divided into two groups of 6 each. Pulpotomies were performed on caries free maxillary first and second molars on both sides of the arch, with MTA and curcumin (24 teeth each), respectively. Access cavities were sealed with resin-modified glass ionomer cement. Postoperative histological evaluation of pulpotomized teeth in both groups was done at 7, 14, and 30 days under a light microscope (×10). Statistical Analysis Used: Data were evaluated with Freidman's test and Mann-Whitney test at 0.05 level. Results: (a) There was a gradual reduction in inflammatory cell response in both groups across time periods tested (MTA P = 0.074, curcumin P = 0.039). (b) The overall architecture of pulp was maintained better in the curcumin group across all time periods tested (P = 0.368). (c) Dentinal bridge formation was consistently seen across time periods tested in MTA group (P = 0.9094) and was feeble in curcumin group (P = 0.9094) across time periods tested. Conclusions: Curcumin has been shown to have wound healing properties. It has the potential to be developed into a predictable and cost-effective vital pulp therapy medicament.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Curcumina/farmacologia , Polpa Dentária/patologia , Polpa Dentária/fisiologia , Óxidos/farmacologia , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Pulpotomia/métodos , Silicatos/farmacologia , Cicatrização/efeitos dos fármacos , Compostos de Alumínio/administração & dosagem , Animais , Compostos de Cálcio/administração & dosagem , Curcumina/administração & dosagem , Combinação de Medicamentos , Óxidos/administração & dosagem , Ratos Wistar , Silicatos/administração & dosagem
15.
ACS Appl Mater Interfaces ; 11(14): 13069-13078, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30883086

RESUMO

Multimodal probes are an asset for simplified, improved medical imaging. In particular, fluorescence and magnetic resonance imaging (MRI) are sought-after combined capabilities. Here, we show that pyrrolidin-2-one-capped manganese oxide nanoparticles (MnOpyrr NPs) combine MRI with fluorescence microscopy to function as efficient bifunctional bio-nanoprobes. We employ a one-pot synthesis for ca. 10 nm MnO NPs, wherein manganese(II) 2,4-pentadionate is thermally decomposed using pyrrolidin-2-one as a solvent and capping ligand. The MnOpyrr NPs are soluble in water without any further postsynthetic modifications. The r1 relaxivity and r2 /r1 ratio indicate that these NPs are potential T1 MRI contrast agents at clinical (3 T) and ultrahigh (9.4 T) magnetic fields. Serendipitously, the as-prepared NPs are photoluminescent. The unexpected luminescence is ascribed to the modification of the pyrrolidin-2-one during the thermal treatment. MnOpyrr NPs are successfully used to enable fluorescence microscopy of HeLa cells, demonstrating bifunctional imaging capabilities. A low cytotoxic response in two distinct cell types (HeLa, HepG2) supports the suitability of MnOpyrr NPs for biological imaging applications.


Assuntos
Meios de Contraste/farmacologia , Imagem por Ressonância Magnética/métodos , Nanopartículas/química , Imagem Óptica/métodos , Meios de Contraste/química , Fluorescência , Células HeLa , Humanos , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Nanopartículas/administração & dosagem , Óxidos/química , Óxidos/farmacologia , Tamanho da Partícula
16.
Mater Sci Eng C Mater Biol Appl ; 99: 696-709, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889743

RESUMO

A green, efficient synthesis of cadmium oxide decorated reduced graphene oxide nanocomposites (RGO/CdO) was prepared by one-step co-precipitation and hydrothermal method. Crystalline nature of the nanocomposites was characterized by X-ray diffraction analysis. To evaluate the structural morphology and particle size, high resolution transmission electron microscopy were used. X-ray photoelectron spectroscopy, Raman spectroscopy and Fourier transform infrared spectroscopy techniques were employed to establish chemical structure of the nanocomposites and Atomic Force Microscopy was done to measure the thickness. The optical properties were evaluated by UV-visible absorption spectroscopy. Thermo-gravimetric analysis, BET surface area and zeta potential measurements were carried out to study the thermal and surface characteristics. The CdO nano-particles (NPs) decorated on RGO sheets exhibit better electrical conductivity compared to RGO. The antibacterial activity of the nanocomposites has also been monitored in different culture media imparting good potentiality than RGO.


Assuntos
Antibacterianos/farmacologia , Compostos de Cádmio/farmacologia , Eletricidade , Grafite/farmacologia , Química Verde/métodos , Nanocompostos/química , Óxidos/farmacologia , Bactérias/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Espectroscopia Fotoeletrônica , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Eletricidade Estática , Temperatura Ambiente , Difração de Raios X
17.
Mater Sci Eng C Mater Biol Appl ; 99: 710-718, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889744

RESUMO

Surface chemistry and topography can determinatively affect the osseointegration of dental implants. Strontium (Sr) has a significant effect on the promotion of bone formation and inhibitation of bone resorption. The emphasis of this study lies on the evaluation of a new surface treatment that aims to improve the early osseointegration of dental implantation both in vitro and in vivo. A hydrothermal method was used to prepare an SrTiO3 incorporation on sandblasted large-grit double acid-etched (SLA) titanium surfaces in SrCl2 solution. The composition and morphology of the SrTiO3 doped surface were analyzed by X-ray diffraction, X-ray photoelectron spectroscopy,and scanning electron microscopy. In addition, the external release figure of Sr was examined by inductively coupled plasma mass spectrometry. The proliferation, adhesion and differentiation of MC3T3-E1 cells on this surface were evaluated in vitro and presented a significant increase in SLA-Sr group compared with that in SLA group. An in vivo study in 24 New Zealand rabbits indicated a remarkable growth in the volume of direct bone-to-implant contact and peri-implant bone in SLA-Sr group, which were compared with SLA group after 3 and 6 weeks, and removal torque tests exhibited a higher torque removal value of SLA-Sr implants. The study gave the result that the biological effect of SLA-Sr implants was significantly superior to that of the SLA implants at the early stage of osseointegration.


Assuntos
Osteogênese/efeitos dos fármacos , Óxidos/farmacologia , Estrôncio/farmacologia , Titânio/farmacologia , Ataque Ácido Dentário , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Íons , Masculino , Camundongos , Nanoestruturas/química , Osteocalcina/metabolismo , Espectroscopia Fotoeletrônica , Coelhos , Estrôncio/química , Propriedades de Superfície , Torque , Difração de Raios X
18.
Mater Sci Eng C Mater Biol Appl ; 99: 374-386, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30889712

RESUMO

Hydrogen trititanate (H2Ti3O7·2H2O) and hydrogen trititanate/Ag2O hybrid nanocomposites (NCs) with novel structure have been synthesized by a simple solvothermal route followed by Na+/H+ ion-exchange. Growths of hydrogen trititanate with nanofiber (HTNF) and nanotube (HTNT) morphologies and hydrogen trititanate-Ag2O (HTFAG and HTTAG) nanocomposites have been tailored by controlling the solvent media. Detailed microstructure characterization of all these samples have been carried out by Rietveld refinement of XRD data and analyzing FESEM/HRTEM micrographs and FTIR spectra. Band gap energies of all these semiconducting samples are obtained from UV-Vis absorption spectra. Both HTFAG and HTTAG NCs exhibit enhanced photocatalytic degradation of organic pollutant (Congo red dye) under visible light, in comparison to HTNF and HTNT respectively due to the formation of a heterojunction between H2Ti3O7·2H2O and Ag2O, which is supported by photoluminescence spectroscopy. HTFAG and HTTAG NCs also show superior antibacterial activity against both gram-negative (Escherichia coli) and gram-positive (Bacillus subtilis) bacteria compared to their pure counterparts. MTT assay reflects a sufficiently high percentage of cell viability and confirms the significant cytocompatibility of all the samples.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Hidrogênio/farmacologia , Luz , Nanocompostos/química , Óxidos/farmacologia , Compostos de Prata/farmacologia , Titânio/farmacologia , Animais , Células CHO , Catálise/efeitos da radiação , Morte Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
19.
Ann Pharm Fr ; 77(2): 126-135, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30709547

RESUMO

OBJECTIVES: This work aims at getting more insights into the distinct behavior of S-oxide derivatives of thiocarbonyl-containing antitubercular drugs, in order to better understand their mechanism of action and toxicity. METHODS: Computational calculation of relative free energy (ΔΔG) of S-oxide tautomers (sulfine R-C [SO]NH2), sulfenic acid (R-C [S-OH]NH) and sulfoxide (R-C [SHO]NH) derived from thioamide and thiourea antitubercular drugs and an update of the literature data with a new point of view about how the structural features of oxidized primary metabolites (S-oxide) can influence the outcome of the reactions and be determinant for the mechanisms of action and of toxicity of these drugs. RESULTS: The calculated free energy of S-oxide tautomers, derived from thioamide and thiourea-type antitubercular drugs, supported by some experimental results, revealed that S-oxide derivatives could be found under sulfine and sulfenic acid forms depending on their chemical structures. Thiocarbonyl compounds belonging to the thioamide series are firstly oxidized, in the presence of H2O2, into the corresponding S-oxide derivatives that are more stable under the sulfine tautomeric form. Otherwise, S-oxides of thiourea-type (acyclic and cyclic) compounds tend to adopt the sulfenic acid tautomeric form preferentially. While the intermediate ethionamide-SO under sulfine form can be isolated and in the presence of H2O2 can undergo further oxidation by a mechanism yielding radical species that are toxic for Mycobacterium tuberculosis and human, thioacetazone-SO, found mainly into sulfenic acid form, is unstable and sufficiently reactive in biological conditions to intercept different biochemical pathways and manifests thus its toxicity. CONCLUSION: Based on experimental and theoretical data, we propose that S-oxide derivatives of thioamide and thiourea-type antitubercular drugs have preference for distinct tautomeric forms. S-oxide of ethioamide is preferentially under sulfine form whereas S-oxide of thiourea compound as thioacetazone is mainly found under sulfenic acid form. These structural features lead to individual chemical reactivities that might explain the distinct mechanism of action and toxicity observed for the thioamide and thiourea antitubercular drugs.


Assuntos
Antituberculosos/química , Antituberculosos/farmacologia , Óxidos/química , Óxidos/farmacologia , Antituberculosos/toxicidade , Cromatografia Líquida de Alta Pressão , Óxidos/toxicidade , Estereoisomerismo , Ácidos Sulfênicos/química , Tioamidas/química , Tioamidas/farmacologia , Tioamidas/toxicidade , Tioureia/química , Tioureia/farmacologia , Tioureia/toxicidade
20.
Ecotoxicol Environ Saf ; 173: 266-272, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30776559

RESUMO

The influence of lime amendment on the absorption and accumulation of lead (Pb) in the grains of three rice cultivars ((Dong Lian 5 (DL-5, Indica), TeYou 009 (TY-009, Hybrid Indica), and YiYou 673 (YY-673, Hybrid Indica)) was investigated and the associated mechanisms were explored. Pot experiment was conducted in heavily Pb-polluted paddy soil. The transformation of Pb species in soil and roots under different levels of lime application was studied by Pb L3-edge X-ray absorption spectroscopy (Pb L3-XAS) and BCR sequential extraction. The results showed that lime amendment significantly increased soil pH and decreased DTPA-extractable Pb in soil. When the additional ratio of Liming was lower than 32 g kg-1, the Pb accumulation in rice plants, particularly in the grains was remarkably reduced. Moreover the biomass of rice was not significantly affected. Among the three cultivars, the lowest Pb content in rice grains occurred in YY-673. The cultivation of rice cultivar with low Pb accumulation will reduce the Pb content in the grains. Liming significantly inhibited the translocation of Pb from the roots to the aboveground parts, and from the stems and leaves to grains. Pb L3-XAS and BCR s sequential extraction method analysis revealed that lime amendment increased Pb2+ association with Fe oxides (Pb-Ferr), the precipitation of 2PbCO3·Pb(OH)2, the residual fraction of paddy soil, and also promoted the transformation of Pb(NO3)2 and Pb-pectin to 2PbCO3·Pb(OH)2 and Pb-Ferr in rice roots. The suitable lime addition (> 4 g kg-1, under this pot experiment) could effectively reduce Pb accumulation in rice grains.


Assuntos
Compostos de Cálcio/farmacologia , Chumbo/metabolismo , Oryza/efeitos dos fármacos , Óxidos/farmacologia , Poluentes do Solo/metabolismo , Grão Comestível/efeitos dos fármacos , Grão Comestível/metabolismo , Poluição Ambiental , Concentração de Íons de Hidrogênio , Oryza/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Solo/química
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