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1.
Braz Oral Res ; 33: e041, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508723

RESUMO

The objective of this study was to evaluate the effect of the hydrofluoridric acid (HF) concentration and time of acid conditioning on bond strength of three glass ceramics to a resin cement. Thus, fifty blocks (10 mm x 5 mm x 2 mm) of each ceramic (LDCAD: IPS e.max CAD; LCAD: IPS Empress CAD and LDHP: IPS e.max Press) were made and embedded in acrylic resin. The surfaces were polished with sandpaper (#600, 800, 1000, and 1200 grits) and blocks were randomly divided into 15 groups (n = 10) according to the following factors: Concentration of HF (10% and 5%), conditioning time (20 s and 60 s) and ceramic (LDCAD, LDHP, and L). After conditioning, silane (Prosil / FGM) was applied and after 2 min, cylinders (Ø = 2 mm; h = 2 mm) of dual resin cement (AllCem / FGM) were made in the center of each block using a Teflon strip as matrix and light cured for 40 s (1,200 mW/cm2). Then, the samples were thermocycled (10,000 cycles, 5/55°C, 30s) and submitted to the shear bond test (50 KgF, 0.5 mm/min). The data (MPa) were analyzed with 3-way ANOVA and Tukey's test (5%). Failure analysis was performed using a stereomicroscope (20x) and a scanning electron microscope (SEM). ANOVA revealed that the "concentration" factor (p = 0.01) and the interaction "acid concentration X ceramic" (p = 0.009) had a significant effect, however, the "ceramic" (p = 0.897) and "conditioning time" (p = 0.260) factors did not influence the results. The LDHP10%60s (10.98 MPa)aA* group presented significantly higher bond strength than LDHP10%20s (6.57 MPa)bA, LCAD5%20s (6,90 ±3,5)aB and LDHP5%60s (5.66 ± 2,9MPa)aA* groups (Tukey). Failure analysis revealed that 100% of specimens had mixed failure. In conclusion, etching with 5% HF for 20 seconds is recommended for lithium disilicate and leucite-reinforced CAD/CAM ceramics. However, for pressed lithium disilicate ceramic, 10% HF for 60 s showed significantly higher bond strength to resin cement.


Assuntos
Ataque Ácido Dentário , Cerâmica/química , Colagem Dentária/métodos , Ácido Fluorídrico/administração & dosagem , Porcelana Dentária/química , Análise do Estresse Dentário , Ácido Fluorídrico/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Cimentos de Resina/química , Resistência ao Cisalhamento , Propriedades de Superfície , Fatores de Tempo
2.
Braz Oral Res ; 33: e040, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31508724

RESUMO

The study characterizes dental implant surfaces treated with phosphoric acid to assess the effects of acid treatment on blood cells and correlate them with cytokine levels. The implant surfaces examined were divided into untreated metal surface (US; n = 50), metal surface treated with phosphoric acid (ATS; n = 50) and cement surface (CS; n = 50) groups. The samples were characterized by scanning electron microscopy (SEM) and rheometry. The implants were incubated with human blood mononuclear cells for 24 h, with surface rinsing in the ATS treatment. Cell viability was determined by colorimetric methods and cytokines in the culture supernatant were quantified using flow cytometry. In the ATS group, the surface porosity and contact surface were increased and plaques were observed on the surface. The blood flow and viscosity curves were similar among the treatments, and the high cell viability rates indicate the biocompatibility of the materials used. An increase in the levels of IL-2, IL-4, IL-6, IL-10 and TNF-α was observed in the ATS and CS groups. There were positive correlations between IL-10 and IL-2 levels and between IL-10 and IL-4 levels in the culture supernatant of the ATS group. The results suggest that implant surface treatment with phosphoric acid activates the production of inflammatory cytokines. The increased cytokine levels can modulate the immune response, thereby improving biofunctional processes and promoting the success of dental implants.


Assuntos
Citocinas/análise , Implantes Dentários , Materiais Dentários/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Ácidos Fosfóricos/farmacologia , Anti-Inflamatórios , Sobrevivência Celular , Citocinas/metabolismo , Cimentos Dentários , Humanos , Interleucina-10/análise , Interleucina-10/metabolismo , Microscopia Eletrônica de Varredura , Reologia , Propriedades de Superfície
3.
Braz Oral Res ; 33: e0045, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31531560

RESUMO

The aim of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on the osteogenic differentiation of dental follicle cells (DFCs) in vitro and on the regenerative effects of DFC-OsteoBoneTM complexes in vivo. DFCs were isolated and characterized. In the in vitro study, DFCs were cultured in an osteogenic medium in the presence or absence of LIPUS. The expression levels of ALP, Runx2, OSX, and COL-I mRNA were analyzed using real-time polymerase chain reaction (RT-PCR) on day 7. Alizarin red staining was performed on day 21. The state of the growth of the DFCs that were seeded on the scaffold at 3, 5, 7, and 9 days was detected by using a scanning electron microscope. In our in vivo study, 9 healthy nude mice randomly underwent subcutaneous transplantation surgery in one of three groups: group A, empty scaffold; group B, DFCs + scaffold; and group C, DFCs + scaffold + LIPUS. After 8 weeks of implantation, a histological analysis was performed by HE and Mason staining. Our results indicate that LIPUS promotes the osteogenic differentiation of DFCs by increasing the expression of the ALP, Runx2, OSX, and COL-I genes and the formation of mineralized nodules. The cells can adhere and grow on the scaffolds and grow best at 9 days. The HE and Mason staining results showed that more cells, fibrous tissue and blood vessels could be observed in the DFCs + scaffold + LIPUS group than in the other groups. LIPUS could promote the osteogenic differentiation of DFCs in vitro and promote tissue regeneration in a DFCs-scaffold complex in vivo. Further studies should be conducted to explore the underlying mechanisms of LIPUS.


Assuntos
Regeneração Óssea/efeitos da radiação , Saco Dentário/citologia , Osteogênese/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas , Animais , Cerâmica , Saco Dentário/efeitos da radiação , Citometria de Fluxo , Camundongos Nus , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Fatores de Tempo
4.
J Biol Regul Homeost Agents ; 33(3 Suppl. 1): 51-61, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538450

RESUMO

This study is to compare the cleaning effectiveness of two Ni-Ti files systems. Thirty single-rooted human teeth were selected and two NiTi rotary systems were used. Group A: canal shaping with ProTaper® Universal (Dentsply Tulsa Dental Specialties, Tulsa, OK) (PTU); Group B: (n=15) canal shaping with Mtwo Ni-Ti instruments (Sweden and Martina, Padova, Italy) and apical finishing with Mtwo Apical Ni-Ti instruments (Sweden and Martina, Padova, Italy). The amount of debris and smear layer were quantified on a basis of a numerical evaluation scale. The data established for scoring the debris and the smear layer was recorded separately and statistically analysed using the Kruskal-Wallis test. No significant differences were found for debris. Mtwo instruments resulted in significantly less smear layer (P less than 0.05) compared with ProTaper® Universal. Under the conditions of this study, Mtwo resulted in significantly less smear layer compared with canal preparation with ProTaper® Universal.


Assuntos
Desenho de Equipamento , Microscopia Eletrônica de Varredura , Preparo de Canal Radicular/instrumentação , Camada de Esfregaço , Humanos , Técnicas In Vitro , Titânio
5.
Anticancer Res ; 39(8): 4533-4537, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366556

RESUMO

BACKGROUND/AIM: Serum-derived macrophage activating factor, serum-MAF, is known to increase the phagocytic activity of macrophages by enhancing the engulfment efficiency. To elucidate the mechanisms underlying phagocytic activation, morphological changes were observed and analyzed. MATERIALS AND METHODS: Morphological changes in macrophages were observed and quantitatively analyzed using scanning electron microscope (SEM) and confocal microscope. RESULTS: SEM and confocal microscopy images revealed frill-like structures and active actin accumulations, respectively, in serum-MAF treated macrophages. Actin accumulation was induced within 5 min following serum-MAF treatment. CONCLUSION: Serum-MAF induced a rapid rearrangement of cytoskeletal actin and enhanced phagocytic activity. Findings of the current study may contribute to the development of techniques that facilitate activation of the human immune system, which in turn may be beneficial for cancer immunotherapy.


Assuntos
Actinas/química , Macrófagos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-maf/farmacologia , Actinas/ultraestrutura , Humanos , Imunoterapia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Microscopia Confocal , Microscopia Eletrônica de Varredura , Proteínas Proto-Oncogênicas c-maf/genética , Células U937 , Proteína de Ligação a Vitamina D/química , Proteína de Ligação a Vitamina D/metabolismo
6.
Chem Commun (Camb) ; 55(66): 9865-9868, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31364624

RESUMO

Au hydrogel with a well-defined nanowire network was rationally designed through one-step dopamine-induced self-assembly. Due to the porous nanostructure along with the polydopamine induced accumulation and interfacial electron transfer effects, the resulting Au hydrogel nanozyme exhibits enhanced glucose oxidase-like activity and peroxidase-like activity, with a biomimetic cascade catalysis.


Assuntos
Biomimética , Dopamina/química , Glucose Oxidase/química , Ouro/química , Hidrogéis/química , Nanopartículas Metálicas/química , Peroxidase/química , Catálise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Oxirredução
7.
An Acad Bras Cienc ; 91(3): e20180237, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365648

RESUMO

The aim of this study was to develop polyurethane (PU) wound dressing incorporated with cobalt nitrate using electrospinning technique. The morphology analysis revealed that the developed composites exhibited reduced fiber and pore diameter than the pristine PU. The electrospun membranes exhibited average porosity in the range of 67% - 71%. Energy-dispersive X-ray spectra (EDS) showed the presence of cobalt in the PU matrix. The interaction of cobalt nitrate with PU matrix was evident in Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The contact angle results indicated the improved wettability of the prepared PU/cobalt nitrate composites (82° ± 2) than the pure PU (100° ± 1). The incorporation of cobalt nitrate into the PU matrix enhanced the surface roughness and mechanical strength as evident in the atomic force microscopy (AFM) and tensile test analysis. The blood compatibility assays revealed the anticoagulant nature of the prepared composites by displaying prolonged blood clotting time than the PU control. Further, the developed composite exhibited less toxicity nature as revealed in the hemolysis and cytotoxicity studies. It was observed that the PU wound dressing added with cobalt nitrate fibers exhibited enhanced physicochemical, better blood compatibility parameters and enhanced fibroblast proliferation rates which may serve as a potential candidate for wound dressings.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Cobalto/administração & dosagem , Teste de Materiais , Engenharia Tecidual , Cicatrização , Materiais Biocompatíveis/química , Cobalto/química , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
8.
An Bras Dermatol ; 94(3): 358-360, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365670

RESUMO

Dermatofibroma is a proliferation of spindle cells located in the dermis. We used scanning electron microscopy to examine two histologically confirmed lesions and observed preserved collagen bundles in the perilesional area. In the lesional area, the collagen was denser, without formation of bundles. Higher magnification showed collagen with mesh-like appearance similar to stretched tufts of cotton. Very high magnification evidenced the tufts of cotton and spindle cells measuring 2 to 12 microns.


Assuntos
Histiocitoma Fibroso Benigno/patologia , Neoplasias Cutâneas/patologia , Derme/patologia , Feminino , Humanos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade
9.
Braz Oral Res ; 33: e057, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365704

RESUMO

The aim of this study was to evaluate the effect of peracetic acid (PAA) as a single irrigant on the smear layer, on the intraradicular dentinal bond strength, and on the penetrability of an epoxy-based resin sealer into the dentinal tubules. A total of 120 roots were distributed into 4 groups according to the irrigant used in root canal preparation: 1% PAA (PAA); 2.5% NaOCl followed by final irrigation with 17% EDTA and 2.5% NaOCl (NaOCl-EDTA-NaOCl); 2.5% NaOCl (NaOCl); and saline solution (SS). The smear layer was evaluated using scanning electron microscopy. The bond strength of an epoxy-based resin sealer (AH Plus) to root dentin was evaluated by the push-out test and penetrability of the sealer into dentinal tubules was observed by confocal laser microscopy. The results were analyzed by the Kruskal-Wallis and the Dunn post-test (α = 0.05). The use of 1% PAA as single root canal irrigant provided smear layer removal and improved the penetrability and bond strength of AH Plus to root dentin in a manner similar to that of the NaOCl-EDTA-NaOCl group (p > 0.05). The NaOCl and SS groups had higher values of smear layer and lower values of sealer penetrability and dentin bond strength than the PAA and NaOCl-EDTA-NaOCl groups (p < 0.05). Thus, 1% PAA has the potential to be used as a single irrigant in root canals.


Assuntos
Cavidade Pulpar/efeitos dos fármacos , Dentina/efeitos dos fármacos , Resinas Epóxi/química , Ácido Peracético/química , Materiais Restauradores do Canal Radicular/química , Irrigantes do Canal Radicular/química , Camada de Esfregaço/química , Colagem Dentária/métodos , Cavidade Pulpar/química , Dentina/química , Ácido Edético/química , Humanos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Hipoclorito de Sódio/química
10.
Sud Med Ekspert ; 62(4): 14-18, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407700

RESUMO

The purpose of the work is to study the possibility of using carbon nanotubes (CNT) as taggants in gun powder to provide expert differentiation of used small firearms cartridges; and to identify the main characteristics of the changes to carbon nanotubes under firing conditions, i.e. short-term exposure to high temperatures and pressures. The principal possibility of using carbon nanotube material for marking gunpowder in small firearms cartridges is stated. There is a need, in both the theory and practice of forensics, to develop such a labeling additive, one that is designed to analyze labeled cartridges and trace their use. We studied the effect of high temperatures and pressures (up to 3000-3500 ºC, 30 MPa) on the behavior of carbon nanotubes by using scanning electron microscopy. We found that the properties of carbon nanotube material - including high chemical and thermal resistance, low prevalence in nature, and a wide variety of forms and configurations - would help solve various investigative issues related to the circumstances of the use of small firearms, in particular, to determine the batch or sample of gunpowder used in the firing of a cartridge.


Assuntos
Armas de Fogo , Balística Forense/métodos , Nanotubos de Carbono , Temperatura Alta , Microscopia Eletrônica de Varredura , Pressão
11.
J Cosmet Sci ; 70(3): 149-159, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31398103

RESUMO

Ilmenite mineral sand was used to synthesize titanium bismonohydrogen orthophosphate monohydrate, Ti(HPO4)2·H2O, and titanium phosphate, TiP2O7, two white pigments suitable in cosmetic applications. Ti(HPO4)2·H2O was obtained after digesting ilmenite in 85% phosphoric acid at 150 °C for 5 hours. On standing, unreacted ilmenite and white Ti(HPO4)2·H2O solid separated into two layers and Ti(HPO4)2·H2O was calcined at 900 °C to obtain the crystalline TiP2O7. Chemical and morphological characteristics were investigated using X-ray diffraction, transmission electron microscopy, scanning electron microscopy coupled with energy dispersive X-ray analysis, Fourier-transform infrared, and X-ray photoelectron spectroscopic techniques. The water retention (WR) capacities were measured at a relative humidity of 57% and indicate that Ti(HPO4)2·H2O and TiP2O7 have increased WR ability when compared with the pigment grade (PG) TiO2. The optical properties of Ti(HPO4)2·H2O, TiP2O7, and PG-TiO2 were compared using Ultraviolet-visible diffuse reflectance spectroscopy. The relative photoactivity of Ti(HPO4)2·H2O and TiP2O7 was determined using a chemical method based on the photobleaching behavior of a stable radical, 1,1-diphenyl 2-picrylhydrazyl. The photoactivities of Ti(HPO4)2·H2O and TiP2O7 are lower than that of PG-TiO2.


Assuntos
Titânio/química , Ferro , Microscopia Eletrônica de Varredura , Minerais
12.
J Appl Oral Sci ; 27: e20180699, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411265

RESUMO

OBJECTIVE: This study investigated the role of extracellular deoxyribonucleic acid (eDNA) on Enterococcus faecalis ( E. faecalis ) biofilm and the susceptibility of E. faecalis to sodium hypochlorite (NaOCl). METHODOLOGY: E. faecalis biofilm was formed in bovine tooth specimens and the biofilm was cultured with or without deoxyribonuclease (DNase), an inhibitor of eDNA. Then, the role of eDNA in E. faecalis growth and biofilm formation was investigated using colony forming unit (CFUs) counting, eDNA level assay, crystal violet staining, confocal laser scanning microscopy, and scanning electron microscopy. The susceptibility of E. faecalis biofilm to low (0.5%) or high (5%) NaOCl concentrations was also analyzed by CFU counting. RESULTS: CFUs and biofilm formation decreased significantly with DNase treatment (p<0.05). The microstructure of DNase-treated biofilms exhibited less structured features when compared to the control. The volume of exopolysaccharides in the DNase-treated biofilm was significantly lower than that of control (p<0.05). Moreover, the CFUs, eDNA level, biofilm formation, and exopolysaccharides volume were lower when the biofilm was treated with DNase de novo when compared to when DNase was applied to matured biofilm (p<0.05). E. faecalis in the biofilm was more susceptible to NaOCl when it was cultured with DNase (p<0.05). Furthermore, 0.5% NaOCl combined with DNase treatment was as efficient as 5% NaOCl alone regarding susceptibility (p>0.05). CONCLUSIONS: Inhibition of eDNA leads to decrease of E. faecalis biofilm formation and increase of susceptibility of E. faecalis to NaOCl even at low concentrations. Therefore, our results suggest that inhibition of eDNA would be beneficial in facilitating the efficacy of NaOCl and reducing its concentration.


Assuntos
Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , DNA Bacteriano/farmacologia , Desoxirribonucleases/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Hipoclorito de Sódio/farmacologia , Animais , Bovinos , Contagem de Colônia Microbiana , Cavidade Pulpar/microbiologia , Testes de Sensibilidade Microbiana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Polissacarídeos Bacterianos/isolamento & purificação , Reprodutibilidade dos Testes , Fatores de Tempo
13.
An Acad Bras Cienc ; 91(3): e20181295, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31432907

RESUMO

The banana tree is associated with different species of endophytic bacteria that can stimulate plant growth. However, further studies are needed to better understand the relationships between this group of bacteria and the host plant. The objective of this study was to investigate the localization of the EB-40 (Bacillus sp.) through anatomical and ultrastructural analyses in micropropagated banana plantlets. The results demonstrated the effective colonization of the EB-40 isolate in the intercellular and intracellular spaces, as well as in the rhizosphere region. The wall of endophytic bacteria contains calcium and nitrogen. The EB-40 isolate was also observed to associate with the plasma membrane and cell wall. These results further our understanding of the mechanisms involved in the colonization of plant cells by endophytic bacteria in micropropagated banana plantlets.


Assuntos
Bacillus/fisiologia , Endófitos/ultraestrutura , Musa/microbiologia , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Bacillus/ultraestrutura , Microscopia Eletrônica de Varredura , Musa/crescimento & desenvolvimento , Musa/ultraestrutura , Raízes de Plantas/crescimento & desenvolvimento
14.
Vet Parasitol ; 273: 90-96, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31454711

RESUMO

Tritrichomonas foetus is a common cause of large bowel diarrhea in cats. Probiotics have been suggested to be effective for many intestinal pathogens; however, there are a lack of studies evaluating the effect of probiotics in T. foetus infection. In vitro studies were performed to evaluate the effect of a probiotic containing Enterococcus faecium (Efm) SF68 and a novel probiotic, Enterococcus hirae, on the inhibition of T. foetus growth, adhesion to, and cytotoxicity towards the intestinal epithelium. The effect of enterococci on T. foetus proliferation during co-culture was evaluated throughout log phase T. foetus growth. The previously validated in vitro co-culture model system using porcine intestinal epithelial cells (IPEC-J2) was used to evaluate the effect of enterococci on T. foetus adhesion and cytotoxicity towards intestinal epithelial cells. Cytotoxicity was assessed using fluorescent microscopy and spectrophotometry. Interactions of T. foetus, enterococci, and intestinal epithelial cells were assessed using scanning electron microscopy and immunofluorescence assays (IFA). Enterococcus-induced inhibition of T. foetus growth was demonstrated at concentrations as low as 104 enterococci colony forming units (CFU)/mL and was dependent, in part, on environmental pH and the presence of viable enterococci organisms. T. foetus adhesion, including with a ronidazole-resistant strain, was reduced with pretreatment of intestinal epithelial cells with enterococci but was not significantly affected when enterococci were introduced simultaneously or following T. foetus infection. Compared to Efm, E. hirae more effectively decreased T. foetus adhesion, suggesting its superior potential as a novel probiotic for T. foetus infection. There was no effect of enterococci treatment on T. foetus-induced intestinal epithelial cell cytotoxicity. Our results support further study into the investigation of a possible benefit of enterococci-containing probiotic treatment for prevention of T. foetus infection in at-risk uninfected cats.


Assuntos
Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Enterococcus/fisiologia , Mucosa Intestinal , Probióticos/farmacologia , Infecções Protozoárias em Animais/microbiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Gatos , Técnica Indireta de Fluorescência para Anticorpo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/parasitologia , Microscopia Eletrônica de Varredura , Tritrichomonas foetus
15.
Pestic Biochem Physiol ; 158: 25-31, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378357

RESUMO

Sodium pheophorbide a (SPA) is a natural photosensitizer. To explore its antifungal activity and mechanism, we studied its inhibitory effects on spore germination and mycelial growth of Pestalotiopsis neglecta. We used sorbitol, 2-thiobarbituric acid (TBA) and electron microscopy to determine its effects on cell wall integrity, cell membrane lipid peroxidation and mycelial morphology. Finally, the effects of SPA on enzyme activity in mycelia were determined. The results showed that SPA effectively inhibited spore germination and mycelial growth of P. neglecta under light conditions (4000 lx, 24 h). Scanning electron microscopy (SEM) revealed that SPA treatment resulted in a roughened, twisted and knotted mycelial surface and abnormal mycelial growth. SPA influenced cell wall integrity, and the content of MDA, a cell membrane lipid peroxidation product was significantly increased (P < 0.05). SPA also significantly inhibited SOD, POD and PG activity, but enhanced PPO activity (P < 0.05). In conclusion, SPA may have potential to become a biological pesticide.


Assuntos
Antifúngicos/farmacologia , Clorofila/análogos & derivados , Micélio/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Clorofila/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Micélio/ultraestrutura
16.
World J Microbiol Biotechnol ; 35(8): 121, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332590

RESUMO

The economics of bioflocculant production is coupled with the use of a low-cost substrate at appropriate culture conditions. The use of a waste substrate for this purpose offers an additional treatment measure to mitigate environmental pollution. We investigated the growth of Aspergillus flavus and its bioflocculant yield using chicken viscera hydrolysate as the sole media. The effects of culture conditions including time, pH, shaker speed, temperature and inoculum size on bioflocculant production were all investigated and optimised through response surface method based on the central component design (CCD) package of Design Expert. Next, the purified bioflocculant was physically and chemically characterised. Under optimised culture conditions (incubation time 72 h, pH 7, shaker speed 150 rpm, temperature 35 °C and inoculum 4%), 6.75 g/L yield of crude bioflocculant was recorded. The bioflocculant activity was mostly distributed in the cell-free supernatant with optimum efficiency of 91.8% at a dose of 4 mL/100 mL Kaolin suspension. The purified bioflocculant was a glycoprotein consisting of 23.46% protein and 74.5% sugar, including 46% neutral sugar and 2.01% uronic acid. The X-ray photoelectron spectroscopy fundamental analysis of the purified bioflocculant indicated that the mass proportion of C, O and N, were 63.46%, 27.87% and 8.86%, respectively. The bioflocculant is mainly composed of carbonyl, amino, hydroxyl, and amide functional groups. This study for the first time indicates a high potential of bioflocculant yield from chicken viscera at the appropriate culture conditions.


Assuntos
Aspergillus flavus/metabolismo , Meios de Cultura/química , Animais , Galinhas , Glicoproteínas/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Vísceras
17.
APMIS ; 127(10): 660-670, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31344275

RESUMO

Multiple approaches were employed to detect pathogens from bone margins associated with Diabetic Foot Osteomyelitis (DFO). Intra-operative bone specimens of 14 consecutive subjects with suspected DFO were collected over a six-month study period from Liverpool Hospital. Infected bone and a proximal bone margins presumed to be 'clean/non-infected' were collected. Bone material was subjected to conventional culture, DNA sequencing and microscopy. In total, eight of 14 (57%) proximal bone margins had no growth by conventional culture but were identified in all proximal bone specimens by DNA sequencing. Proximal margins had lower median total microbial counts than infected specimens, but these differences were not statistically significant. Pathogens identified by sequencing in infected specimens were identified in proximal margins and the microbiomes were similar (ANOSIM = 0.02, p = 0.59). Using a combination of SEM and/or PNA-FISH, we visualized the presence of microorganisms in infected bone specimens and their corresponding proximal margins of seven patients (50%) with DFO. We identify that bacteria can still reside in what seems to be proximal 'clean' margins. The significance and implications of clinical outcomes requires further analysis from a larger sample size that incorporates differences in surgical and post-operative approaches, correlating any outcomes back to culture-sequence findings.


Assuntos
Bactérias/isolamento & purificação , Técnicas Bacteriológicas/métodos , Osso e Ossos/microbiologia , Pé Diabético/microbiologia , Histocitoquímica/métodos , Metagenômica/métodos , Osteomielite/microbiologia , Bactérias/classificação , Bactérias/genética , Osso e Ossos/cirurgia , Pé Diabético/patologia , Pé Diabético/cirurgia , Humanos , Hibridização in Situ Fluorescente , Microscopia Eletrônica de Varredura , Osteomielite/patologia , Osteomielite/cirurgia , Análise de Sequência de DNA
18.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 54(7): 475-480, 2019 Jul 09.
Artigo em Chinês | MEDLINE | ID: mdl-31288328

RESUMO

Objective: To observe the effect of adenosine triphosphate (ATP) phosphorylation on type Ⅰ collagen mineralization and explore the role of small molecule compound ATP in biomimetic mineralization. Methods: Fourier transform infrared spectroscopy (FT-IR) was used to analyze the phosphorylation of collagen molecules by different concentrations (0, 25, 50, 100 mmol/L) of ATP. The concentration of 50 mmol/L ATP was chosen to construct the phosphorylated collagen mineralization model. Transmission electron microscopy (TEM) was used to observed the ultrastructure of mineralized collagen and the collagen mineralization rate was further calculated by ImageJ software. The surface morphology of the collagen gel ATP group and the control group was observed by scanning electron microscopy (SEM) and the elemental analysis was performed by using an X-ray energy spectrometer. The artificial demineralized dentin samples were mineralized for 2 days and 4 days to compare the effect of ATP on dentin remineralization by SEM. Results: FT-IR analysis showed that the formation of new peaks at wavenumbers of 642, 818, and 902 cm(-1) indicated that ATP can phosphorylate type Ⅰ collagen. Through TEM and SEM observation, the mineralization degree of type Ⅰ collagen and demineralized dentin pretreated with 50 mmol/L ATP were significantly higher than that of the control group. Compared with the control group [(31.65±1.62)%], the mineralization rate of collagen in the ATP group [(100±0)%] was significantly increased after 2 days of mineralization (P<0.05). Conclusions: ATP phosphorylation can effectively promote the mineralization process of type Ⅰ collagen.


Assuntos
Trifosfato de Adenosina , Materiais Biomiméticos , Colágeno Tipo I , Trifosfato de Adenosina/farmacologia , Materiais Biomiméticos/química , Colágeno Tipo I/química , Colágeno Tipo I/metabolismo , Colágeno Tipo I/ultraestrutura , Dentina/química , Dentina/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Fosforilação , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Int J Nanomedicine ; 14: 4589-4599, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31296988

RESUMO

Purpose: Ferulic acid (FA) is a poorly water-soluble natural antioxidant with anticancer activity. This poor solubility limits the application of FA in the food and pharmaceutical industry. Cyclodextrin nanosponges (CD-NSs) are a novel group of cross-linked CD derivatives which can be used to enhance the solubility of low-soluble bioactive compounds. Methods: In this study, FA was encapsulated into the NSs in the proportion of 1:4 (FA:NS). Diphenyl carbonate was used as a cross-linker in different proportions with ß-CD. Characterization of obtained NSs was performed using scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) analysis. Results: Our results revealed that the solubility of encapsulated FA was increased up to fifteenfold compared with pure FA in the proportion of 1:4 (CD:cross-linker). The results of FTIR, XRD, and DSC confirmed the interaction of FA with NSs. The cytotoxicity of encapsulated FA against MCF7 and 4T1 breast cancer cell lines was investigated using different concentrations of FA in 24, 48, and 72 hrs. The cytotoxicity assay indicated that FA treatment reduced viability and enhanced apoptosis of cancer cells. IC50 value of encapsulated FA (250 ppm) was decreased by threefold when compared with pure FA (750 ppm). Conclusion: In general, CD-NS was found to be a suitable delivery system for poorly soluble bioactives such as FA.


Assuntos
Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Ciclodextrinas/química , Nanoestruturas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Humanos , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X
20.
Anal Bioanal Chem ; 411(21): 5593-5603, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31289896

RESUMO

A novel SBA-15-based fluorescent sensor, SBA-PI: mesoporous SBA-15 structure modified with iminostilbene groups, was designed, synthesized, and characterized by Fourier transform-infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), low-angle X-ray diffraction techniques (low-angle XRD), and N2 adsorption-desorption techniques. The SBA-PI as a sensor with a selective behavior for detection of Cu2+ comprises iminostilbene carbonyl as the fluorophore group. The SBA-PI sensor displays an excellent fluorescence response in aqueous solutions and the fluorescence intensity quenches remarkably upon addition of Cu2+. Other common interfering ions even at high concentration ratio showed either no or very small changes in the fluorescence intensity of SBA-PI in the absence of Cu2+. A limit of detection of 8.7 × 10-9 M for Cu2+ indicated that this fluorescence sensor has a high sensitivity and selectivity toward the target copper (II) ion. The fabricated Cu2+ sensor was successfully applied for the determination of the Cu2+ in human blood samples without any significant interference. With the selective analysis of Cu2+ ions down to 0.9 nM in blood, the sensor is a promising and a novel detection candidate for Cu2+ and can be applied in the clinical laboratory. A reversibility and accuracy in the fluorescence behavior of the sensor was found in the presence of I¯ that was described as a masking agent for Cu2+. Graphical abstract.


Assuntos
Cobre/sangue , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Oligoelementos/sangue , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de Pó , Espectrometria por Raios X , Termogravimetria
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