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1.
Virol J ; 21(1): 120, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816738

RESUMO

BACKGROUND: The Porcine Epidemic Diarrhea Virus (PEDV) has caused significant economic losses in the global swine industry. As a potential drug for treating diarrhea, the antiviral properties of attapulgite deserve further study. METHODS: In this study, various methods such as RT-qPCR, Western blot, viral titer assay, Cytopathic Effect, immunofluorescence analysis and transmission electron microscopy were used to detect the antiviral activity of attapulgite and to assess its inhibitory effect on PEDV. RESULTS: When exposed to the same amount of virus, there was a significant decrease in the expression of the S protein, resulting in a viral titer reduction from 10-5.613 TCID50/mL to 10-2.90 TCID50/mL, which represents a decrease of approximately 102.6 folds. Results of cytopathic effect and indirect immunofluorescence also indicate a notable decrease in viral infectivity after attapulgite treatment. Additionally, it was observed that modified materials after acidification had weaker antiviral efficacy compared to powdered samples that underwent ultrasonic disintegration, which showed the strongest antiviral effects. CONCLUSION: As a result, Attapulgite powders can trap and adsorb viruses to inhibit PEDV in vitro, leading to loss of viral infectivity. This study provides new materials for the development of novel disinfectants and antiviral additives.


Assuntos
Antivirais , Vírus da Diarreia Epidêmica Suína , Compostos de Silício , Vírus da Diarreia Epidêmica Suína/efeitos dos fármacos , Vírus da Diarreia Epidêmica Suína/genética , Vírus da Diarreia Epidêmica Suína/fisiologia , Animais , Antivirais/farmacologia , Compostos de Silício/farmacologia , Compostos de Silício/química , Chlorocebus aethiops , Compostos de Magnésio/farmacologia , Suínos , Células Vero , Carga Viral/efeitos dos fármacos , Efeito Citopatogênico Viral/efeitos dos fármacos , Doenças dos Suínos/virologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/veterinária , Microscopia Eletrônica de Transmissão
2.
Pestic Biochem Physiol ; 202: 105959, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879341

RESUMO

ε-Poly-l-lysine (ε-PL) is an effective antimicrobial peptide for controlling fungal plant diseases, exhibiting significant antifungal activity and safety. Despite its known efficacy, the potential of ε-PL in combating plant bacterial diseases remains underexplored. This study evaluated the effectiveness of ε-PL and its nanomaterial derivative in managing tomato bacterial spot disease caused by Pseudomonas syringae pv. tomato. Results indicated that ε-PL substantially inhibited the growth of Pseudomonas syringae pv. tomato. Additionally, when ε-PL was loaded onto attapulgite (encoded as ATT@PL), its antibacterial effect was significantly enhanced. Notably, the antibacterial efficiency of ATT@PL containing 18.80 µg/mL ε-PL was even close to that of 100 µg/mL pure ε-PL. Further molecular study results showed that, ATT@PL stimulated the antioxidant system and the salicylic acid signaling pathway in tomatoes, bolstering the plants disease resistance. Importantly, the nanocomposite demonstrated no negative effects on both seed germination and plant growth, indicating its safety and aligning with sustainable agricultural practices. This study not only confirmed the effectiveness of ε-PL in controlling tomato bacterial spot disease, but also introduced an innovative high antibacterial efficiency ε-PL composite with good bio-safety. This strategy we believe can also be used in improving other bio-pesticides, and has high applicability in agriculture practice.


Assuntos
Antibacterianos , Doenças das Plantas , Polilisina , Pseudomonas syringae , Compostos de Silício , Solanum lycopersicum , Pseudomonas syringae/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Polilisina/farmacologia , Polilisina/química , Antibacterianos/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Compostos de Silício/farmacologia , Compostos de Silício/química , Compostos de Magnésio
3.
Int J Mol Sci ; 24(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37628838

RESUMO

Hydrolytic reactions taking place at the surface of a silicon nitride (Si3N4) bioceramic were found to induce instantaneous inactivation of Human herpesvirus 1 (HHV-1, also known as Herpes simplex virus 1 or HSV-1). Si3N4 is a non-oxide ceramic compound with strong antibacterial and antiviral properties that has been proven safe for human cells. HSV-1 is a double-stranded DNA virus that infects a variety of host tissues through a lytic and latent cycle. Real-time reverse transcription (RT)-polymerase chain reaction (PCR) tests of HSV-1 DNA after instantaneous contact with Si3N4 showed that ammonia and its nitrogen radical byproducts, produced upon Si3N4 hydrolysis, directly reacted with viral proteins and fragmented the virus DNA, irreversibly damaging its structure. A comparison carried out upon testing HSV-1 against ZrO2 particles under identical experimental conditions showed a significantly weaker (but not null) antiviral effect, which was attributed to oxygen radical influence. The results of this study extend the effectiveness of Si3N4's antiviral properties beyond their previously proven efficacy against a large variety of single-stranded enveloped and non-enveloped RNA viruses. Possible applications include the development of antiviral creams or gels and oral rinses to exploit an extremely efficient, localized, and instantaneous viral reduction by means of a safe and more effective alternative to conventional antiviral creams. Upon incorporating a minor fraction of micrometric Si3N4 particles into polymeric matrices, antiherpetic devices could be fabricated, which would effectively impede viral reactivation and enable high local effectiveness for extended periods of time.


Assuntos
Herpesvirus Humano 1 , Humanos , Compostos de Silício/farmacologia , Antivirais/farmacologia , DNA Viral
4.
Int J Mol Sci ; 23(12)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35742996

RESUMO

Silicon nitride possesses a variety of excellent properties that can be specifically designed and manufactured for different medical applications. On the one hand, silicon nitride is known to have good mechanical properties, such as high strength and fracture toughness. On the other hand, the uniqueness of the osteogenic/antibacterial dualism of silicon nitride makes it a favorable bioceramic for implants. The surface of silicon nitride can simultaneously inhibit the proliferation of bacteria while supporting the physiological activities of eukaryotic cells and promoting the healing of bone tissue. There are hardly any biomaterials that possess all these properties concurrently. Although silicon nitride has been intensively studied as a biomedical material for years, there is a paucity of comprehensive data on its properties and medical applications. To provide a comprehensive understanding of this potential cornerstone material of the medical field, this review presents scientific and technical data on silicon nitride, including its mechanical properties, osteogenic behavior, and antibacterial capabilities. In addition, this paper highlights the current and potential medical use of silicon nitride and explains the bottlenecks that need to be addressed, as well as possible solutions.


Assuntos
Cerâmica , Compostos de Silício , Antibacterianos/farmacologia , Materiais Biocompatíveis , Compostos de Silício/farmacologia
5.
J Mater Sci Mater Med ; 30(4): 43, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30929122

RESUMO

Robust cell adhesion is known to be necessary to promote cell colonization of biomaterials and differentiation of progenitors. In this paper, we propose the functionalization of Silicon Oxycarbide (SiOxCy) nanowires (NWs) with 3-mercaptopropyltrimethoxysilane (MPTMS), a molecule containing a terminal -SH group. The aim of this functionalization was to develop a surface capable to adsorb proteins and promote cell adhesion, proliferation and a better deposition of extracellular matrix. This functionalization can be used to anchor other structures such as nanoparticles, proteins or aptamers. It was observed that surface functionalization markedly affected the pattern of protein adsorption, as well as the in vitro proliferation of murine osteoblastic cells MC3T3-E1, which was increased on functionalized nanowires (MPTMS-NWs) compared to bare NWs (control) (p < 0.0001) after 48 h. The cells showed a better adhesion on MPTMS-NWs than on bare NWs, as confirmed by immunofluorescence studies on the cytoskeleton, which showed a more homogeneous vinculin distribution. Gene expression analysis showed higher expression levels for alkaline phosphatase and collagen I, putative markers of the osteoblast initial differentiation stage. These results suggest that functionalization of SiOxCy nanowires with MPTMS enhances cell growth and the expression of an osteoblastic phenotype, providing a promising strategy to improve the biocompatibility of SiOxCy nanowires for biomedical applications.


Assuntos
Adesão Celular/efeitos dos fármacos , Nanofios/química , Osteoblastos/efeitos dos fármacos , Compostos de Silício/farmacologia , Compostos de Sulfidrila/farmacologia , Alicerces Teciduais/química , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Teste de Materiais , Camundongos , Nanofios/efeitos adversos , Compostos de Organossilício , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Espectroscopia Fotoeletrônica , Silanos/química , Silanos/farmacologia , Compostos de Silício/química , Compostos de Sulfidrila/química , Propriedades de Superfície , Alicerces Teciduais/efeitos adversos
6.
Int J Mol Sci ; 20(3)2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30744184

RESUMO

Tremendous efforts are applied in the ferroalloy industry to control and reduce exposure to dust generated during the production process, as inhalable Mn-containing particulate matter has been linked to neurodegenerative diseases. This study aimed to investigate the toxicity and biological effects of dust particles from laboratory-scale processes where molten silicomanganese (SiMn) was exposed to air, using a human astrocytoma cell line, 1321N1, as model system. Characterization of the dust indicated presence of both nano-sized and larger particles averaging between 100 and 300 nm. The dust consisted mainly of Si, Mn and O. Investigation of cellular mechanisms showed a dose- and time-dependent effect on cell viability, with only minor changes in the expression of proteins involved in apoptosis. Moreover, gene expression of the neurotoxic biomarker amyloid precursor protein (APP) increased, whereas APP protein expression decreased. Finally, induction of gap junctional intercellular communication (GJIC) increased with higher doses and correlated with the other endpoints. Thus, the effects of SiMn dust on 1321N1 cells are highly dependent on the dose of exposure and involves changes in APP, apoptosis-related proteins and intercellular communication.


Assuntos
Antineoplásicos/farmacologia , Poeira , Manganês/farmacologia , Compostos de Silício/farmacologia , Antineoplásicos/química , Astrocitoma , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Manganês/química , Nanotecnologia , Exposição Ocupacional , Compostos de Silício/química
7.
Cell Biol Int ; 42(3): 353-364, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29105212

RESUMO

The aim of this study was to investigate the in vitro effect of Silicon, in the soluble form of sodium orthosilicate, combined and not with the concentrated growth factors (CGF), a platelet-rich preparation, on three different human cell lines of fibroblasts (NHDF), endothelial cells (HUVEC), and osteoblasts (HOBs). Each cell type was treated with sodium orthosilicate at the final concentration of 0.5 mM and 1 mM, CGF, and sodium orthosilicate combined with CGF, for 72 h. At the end of the experimental period, the in vitro effect on cell growth, proliferation, and metabolic activity was evaluated by performing a simple cell count, using an automated cell counter and by evaluating the expression of the intracellular proliferation marker Ki-67, using Fluorescence-activated cell sorting (FACS) analysis. Moreover, the expression of other cell markers and active molecules, such as Collagen type I, Osteopontin, Vascular Endothelial Growth Factor, and endothelial Nitric Oxide Synthase, was evaluated, through immunohistochemistry. Results obtained showed that the combined use of CGF and sodium orthosilicate stimulates cell growth, proliferation, and metabolic activity, suggesting that this treatment could be effective in tissue regeneration.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Compostos de Silício/farmacologia , Plaquetas , Contagem de Células , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Osteoblastos/efeitos dos fármacos , Compostos de Silício/metabolismo , Sódio
8.
J Anim Physiol Anim Nutr (Berl) ; 102(6): 1574-1584, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30113108

RESUMO

This experiment was designed to investigate effects of different levels of modified palygorskite (MPal) supplementation on growth performance, immunity, oxidative status and intestinal integrity and barrier function of broilers. A total of 320 1-day-old Arbor Acres broilers were randomly assigned into 5 dietary treatments and fed a basal diet supplemented with 0, 0.25, 0.5, 1 and 2 g/kg MPal, respectively, for a 42-day feeding trial. Treatments quadratically reduced feed/gain ratio (F:G) during 1-21 days and linearly decreased average daily feed intake and F:G during 22-42 days, and linearly and quadratically decreased average daily feed intake and F:G during overall period (p < 0.05, 0.50 g/kg treatment showed the lowest F:G). MPal supplementation increased the contents of 21-day jejunal secretory immunoglobulin A (SIgA) quadratically, and 21-day jejunal immunoglobulin G (IgG), immunoglobulin M (IgM) and 42-day jejunal total superoxide dismutase (T-SOD) activity linearly and quadratically (0.50 g/kg treatment showed the highest immunoglobulin concentration), whereas linearly reduced 21-day ileal SIgA level and 42-day jejunal malondialdehyde (MDA) accumulation and serum diamine oxidase activity, and quadratically decreased 21-day ileal MDA level (p < 0.05). The 42-day jejunal SIgA, IgG and IgM concentrations, and T-SOD activity in jejunum at 21 days and ileum at both 21 days and 42 days were quadratically increased with MPal administration (p < 0.05, 0.50 g/kg treatment showed the highest T-SOD activity). The mucin 2 mRNA abundances in 42-day jejunum and 21-day ileum were quadratically increased with MPal supplementation (p < 0.05). Treatments linearly increased 42-day ileal zonula occludens-1, claudin-3 and jejunal claudin-3 mRNA level, whereas linearly and quadratically increased ileal claudin-2 mRNA level (p < 0.05). In conclusion, MPal supplementation exhibited beneficial effects on growth performance, intestinal immunity, antioxidant capacity and intestinal integrity and barrier function of broiler with its optimum dosage being 0.5 g/kg.


Assuntos
Galinhas/crescimento & desenvolvimento , Intestinos/efeitos dos fármacos , Compostos de Magnésio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Compostos de Silício/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Compostos de Magnésio/administração & dosagem , Distribuição Aleatória , Compostos de Silício/administração & dosagem , Superóxido Dismutase
9.
Langmuir ; 32(12): 3024-35, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26948186

RESUMO

Organisms of Gram-negative phylum bacteroidetes, Porphyromonas gingivalis, underwent lysis on polished surfaces of silicon nitride (Si3N4) bioceramics. The antibacterial activity of Si3N4 was mainly the result of chemically driven principles. The lytic activity, although not osmotic in nature, was related to the peculiar pH-dependent surface chemistry of Si3N4. A buffering effect via the formation of ammonium ions (NH4(+)) (and their modifications) was experimentally observed by pH microscopy. Lysis was confirmed by conventional fluorescence spectroscopy, and the bacteria's metabolism was traced with the aid of in situ Raman microprobe spectroscopy. This latter technique revealed the formation of peroxynitrite within the bacterium itself. Degradation of the bacteria's nucleic acid, drastic reduction in phenilalanine, and reduction of lipid concentration were observed due to short-term exposure (6 days) to Si3N4. Altering the surface chemistry of Si3N4 by either chemical etching or thermal oxidation influenced peroxynitrite formation and affected bacteria metabolism in different ways. Exploiting the peculiar surface chemistry of Si3N4 bioceramics could be helpful in counteracting Porphyromonas gingivalis in an alkaline pH environment.


Assuntos
Antibacterianos/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Compostos de Silício/farmacologia , Amônia/metabolismo , Antibacterianos/química , Proteínas de Bactérias/metabolismo , Bacteriólise , Cerâmica , DNA Bacteriano/metabolismo , Concentração de Íons de Hidrogênio , Ácido Peroxinitroso/metabolismo , Fosfolipídeos/metabolismo , Porphyromonas gingivalis/metabolismo , RNA Bacteriano/metabolismo , Compostos de Silício/química , Dióxido de Silício
10.
J Appl Microbiol ; 120(4): 1033-40, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26725456

RESUMO

AIMS: The objective of this study was twofold: (i) to examine the effect of early-posthatch dietary inclusion of the clay mineral palygorskite on laying pullets' growth and (ii) to determine the potential effects of the latter diet on caecal microbial communities. METHODS AND RESULTS: Four hundred and thirty-two female, 1-day-old Hyline Brown chickens were equally and randomly allocated to two dietary treatment groups; control and palygorskite (0 and 0·5% palygorskite respectively). They were reared in floor pens for 18 weeks. Feed intake, feed conversion ratio, body weight gain and uniformity were assessed. At the end of the rearing period, 53 birds per group were transferred to laying cages without any changes in their respective dietary treatments. At onset of lay, eight birds from each group were euthanized and their caeca were obtained for analysis. Culture-independent and sequencing-based methods were used to analyse caecal microbial composition. CONCLUSIONS: Palygorskite dietary supplementation increased the uniformity of the relative group at the end of the rearing period. Pullets that received palygorskite had different and more homogeneous caecal microbial profiles at onset of lay when compared to controls. Moreover, in the caeca of the former pullets a more favourable microbiota was evident; it comprised largely of bacteria that are major degraders of resistant polysaccharides and efficient in butyrate production. SIGNIFICANCE AND IMPACT OF THE STUDY: The novelty of this study lies to the beneficial effect of palygorskite (a clay mineral) to pullets growth and health, likely through modulation of the gut microbiota.


Assuntos
Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais , Compostos de Magnésio/farmacologia , Compostos de Silício/farmacologia , Animais , Galinhas/microbiologia , Feminino , Microbiota/efeitos dos fármacos
11.
Am J Dent ; 28(2): 90-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26087574

RESUMO

PURPOSE: To compare the dentin tubule-occluding ability of fluoroaluminocalciumsilicate-based (Nanoseal), calcium phosphate-based (Teethmate Desensitizer), resin-containing oxalate (MS Coat ONE) and diamine silver fluoride (Saforide) dentin desensitizers using artificially demineralized bovine dentin. METHODS: Simulated hypersensitive dentin was created using cervical dentin sections derived from bovine incisors using phosphoric acid etching followed by polishing with a paste containing hydroxyapatite. The test desensitizers were applied in one, two, or three cycles, where each cycle involved desensitizer application, brushing, and immersion in artificial saliva (n= 5 each). The dentin surfaces were examined with scanning electron microscopy, and the dentin tubule occlusion rate was calculated. The elemental composition of the deposits was analyzed with electron probe microanalysis. Data were analyzed by one-way ANOVA and the Tukey honestly significant different test. RESULTS: Marked deposit formation was observed on the specimens treated with Nanoseal or Teethmate Desensitizer, and tags were detected in the specimens' dentin tubules. These findings became more prominent as the number of application cycles increased. The major elemental components of the tags were Ca, F, and Al (Nanoseal) and Ca and P (Teethmate Desensitizer). The tubule occlusion rates of MS Coat ONE and Saforide were significantly lower than those of Nanoseal and Teethmate Desensitizer (P< 0.05).


Assuntos
Dessensibilizantes Dentinários/farmacologia , Dentina/efeitos dos fármacos , Alumínio/análise , Compostos de Alumínio/farmacologia , Animais , Cálcio/análise , Fosfatos de Cálcio/farmacologia , Bovinos , Dentina/ultraestrutura , Sensibilidade da Dentina/patologia , Durapatita/farmacologia , Microanálise por Sonda Eletrônica , Fluoretos/farmacologia , Fluoretos Tópicos , Microscopia Eletrônica de Varredura , Nanopartículas , Oxalatos/farmacologia , Fósforo/análise , Compostos de Amônio Quaternário/farmacologia , Distribuição Aleatória , Saliva Artificial/química , Compostos de Silício/farmacologia , Compostos de Prata , Escovação Dentária/instrumentação
12.
ACS Biomater Sci Eng ; 10(6): 4059-4072, 2024 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-38748565

RESUMO

The silicon nitride (Si3N4) coating exhibits promising potential in oral applications due to its excellent osteogenic and antibacterial properties. However, a comprehensive investigation of Si3N4 coatings in the context of dental implants is still lacking, especially regarding their corrosion resistance and in vivo performance. In this study, Si3N4 coatings were prepared on a titanium surface using the nonequilibrium magnetron sputtering method. A systematic comparison among the titanium group (Ti), Si3N4 coating group (Si3N4-Ti), and sandblasted and acid-etched-treated titanium group (SLA-Ti) has been conducted in vitro and in vivo. The results showed that the Si3N4-Ti group had the best corrosion resistance and antibacterial properties, which were mainly attributed to the dense structure and chemical activity of Si-O and Si-N bonds on the surface. Furthermore, the Si3N4-Ti group exhibited superior cellular responses in vitro and new bone regeneration and osseointegration in vivo, respectively. In this sense, silicon nitride coating shows promising prospects in the field of dental implantology.


Assuntos
Antibacterianos , Materiais Revestidos Biocompatíveis , Implantes Dentários , Osteogênese , Compostos de Silício , Titânio , Titânio/química , Titânio/farmacologia , Compostos de Silício/química , Compostos de Silício/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/administração & dosagem , Osteogênese/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Animais , Propriedades de Superfície , Osseointegração/efeitos dos fármacos , Camundongos , Teste de Materiais , Corrosão
13.
Int J Biol Macromol ; 275(Pt 1): 133399, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945323

RESUMO

The development of efficient, safe, environmentally friendly, and user-friendly hemostatic dressings remains a great challenge for researchers. A variety of clay minerals and plant extracts have garnered considerable attention due to their outstanding hemostatic efficacy and favorable biosafety. In this study, a facile solution casting strategy was employed to prepare nanocomposite films by incorporating natural nanorod-like palygorskite (Pal) and herb-derived hemostat dencichine (DC) based on chitosan and polyvinylpyrrolidone. The dynamic blood clotting index demonstrated that the nanocomposite film with a DC addition of 1.0 wt% exhibited significantly superior hemostatic properties compared to both pure DC powder or commercial hemostatic agent Yunnan Baiyao. This improvement was primarily attributed to proper blood affinity, increased porosity, enhanced adhesion of platelets and erythrocytes, as well as the accelerated activation of coagulation factors and platelets. Under the synergistic effect of Pal and DC, the nanocomposite film displayed suitable tensile strength (20.58 MPa) and elongation at break (47.29 %), which may be due to the strong intermolecular hydrogen bonding and electrostatic interaction between Pal/DC and macropolymers. Notably, the nanocomposite film exhibited remarkable antibacterial effectiveness and desirable cytocompatibility, as well as the capability of promoting wound healing in vitro. Taken together, the nanocomposite film synergized with Pal and DC is expected to be an efficacious and suitable wound dressing.


Assuntos
Quitosana , Hemostasia , Hemostáticos , Compostos de Magnésio , Nanocompostos , Povidona , Compostos de Silício , Cicatrização , Nanocompostos/química , Quitosana/química , Povidona/química , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Compostos de Silício/química , Compostos de Silício/farmacologia , Hemostáticos/química , Hemostáticos/farmacologia , Hemostasia/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Animais , Humanos , Coagulação Sanguínea/efeitos dos fármacos , Bandagens
14.
J Mech Behav Biomed Mater ; 155: 106579, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749266

RESUMO

Silicon nitride is utilized clinically as a bioceramic for spinal fusion cages, owing to its high strength, osteoconductivity, and antibacterial effects. Nevertheless, silicon nitride exhibits suboptimal damping properties, a critical factor in mitigating traumatic bone injuries and fractures. In fact, there is a scarcity of spinal implants that simultaneously demonstrate proficient damping performance and support osteogenesis. In our study, we fabricated a novel sodium alginate-silicon nitride/poly(vinyl alcohol) (SA-SiN/PVA) composite scaffold, enabling enhanced energy absorption and rapid elastic recovery under quasi-static and impact loading scenarios. Furthermore, the study demonstrated that the incorporation of physical and chemical cross-linking significantly improved stiffness and recoverable energy dissipation. Concerning the interaction between cells and materials, our findings suggest that the addition of silicon nitride stimulated osteogenic differentiation while inhibiting Staphylococcus aureus growth. Collectively, the amalgamation of ceramics and tough hydrogels facilitates the development of advanced composites for spinal implants, manifesting superior damping, osteogenic potential, and antibacterial properties. This approach holds broader implications for applications in bone tissue engineering.


Assuntos
Alginatos , Materiais Biocompatíveis , Teste de Materiais , Álcool de Polivinil , Compostos de Silício , Staphylococcus aureus , Alginatos/química , Alginatos/farmacologia , Álcool de Polivinil/química , Compostos de Silício/química , Compostos de Silício/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Osteogênese/efeitos dos fármacos , Fenômenos Mecânicos , Alicerces Teciduais/química , Humanos
15.
Langmuir ; 29(17): 5279-85, 2013 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-23547786

RESUMO

In order to extend the antibacterial time of quaternary phosphonium salt in bacteria, palygorskite (PGS) is used as the carrier of dodecyl triphenyl phosphonium bromide (DTP), and a DTP-PGS hybrid is prepared. Antibacterial performance of this novel hybrid is investigated for both Gram-positive and Gram-negative bacteria. The results show that the DTP could be absorbed on the surface of PGS which had bacteria-adsorbed capability. The DTP-PGS hybrid, combining the advantages of PGS and DTP, display specific-targeting capability, long-term antibacterial activity, and lower cytotoxicity, suggesting the great potential application as PGS-based antibacterial powder.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Magnésio/farmacologia , Organofosfonatos/química , Compostos de Silício/farmacologia , Adsorção , Antibacterianos/química , Antineoplásicos/química , Bactérias/química , Bactérias/crescimento & desenvolvimento , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Compostos de Magnésio/química , Testes de Sensibilidade Microbiana , Sais/química , Compostos de Silício/química , Relação Estrutura-Atividade , Propriedades de Superfície
16.
Am J Dent ; 26(4): 191-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24693628

RESUMO

PURPOSE: To investigate the effect of a fluoride-containing aluminocalciumsilicate nanoparticle glass dispersed aqueous solution (Nanoseal) on enamel and dentin, under the hypothesis that this material can form insoluble mineral deposits that confer acid resistance to the tooth structure and occlude open dentin tubules. METHODS: Labial enamel and dentin of human extracted incisors were used. Morphology of the enamel and dentin artificially demineralized with a lactic acid solution that before and/or after coated with the test material were analyzed with a wavelength-dispersive X-ray spectroscopy electron probe microanalyzer with an image observation function (SEM-EPMA). Moreover, incorporation of the calcium and silicon by enamel and dentin were also detected with SEM-EPMA. RESULTS: Application of the fluoroaluminocalciumsilicate-based tooth coating material resulted in the deposition of substances (nanoparticles) onto the enamel surface porosities and open dentin tubules on the artificial lesions. Prior coating with the test material reduced the demineralization-induced loss of enamel and dentin. Moreover, Ca and Si incorporation into superficial enamel and dentin was detected.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Fluoretos/farmacologia , Nanopartículas/química , Silicatos/farmacologia , Compostos de Silício/farmacologia , Cálcio/farmacocinética , Cariostáticos/farmacologia , Esmalte Dentário/ultraestrutura , Solubilidade do Esmalte Dentário/efeitos dos fármacos , Dentina/ultraestrutura , Dessensibilizantes Dentinários/farmacologia , Solubilidade da Dentina/efeitos dos fármacos , Microanálise por Sonda Eletrônica , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Microscopia Eletrônica de Varredura , Saliva Artificial/química , Silício/farmacocinética , Espectrometria por Raios X , Temperatura , Fatores de Tempo , Desmineralização do Dente/patologia
17.
Biomater Adv ; 153: 213569, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37531822

RESUMO

This study reported the development of a composite sponge (ACATS) based on alkylated chitosan (AC) and attapulgite (AT) for rapid hemostasis. The well-designed ACATS, with an optimal AC N-alkylation of 5.9 % and an optimal AC/AT mass ratio of 3:1, exhibited a hierarchical porous structure with a favorable biocompatibility. The ACATS can effectively and rapidly stop the uncontrolled bleeding in 235 ± 64 s with a total blood loss of 8.4 ± 4.0 g in comparison with those of Celox as a positive control (602 ± 101 s and 22.3 ± 2.4 g, respectively) using rabbit carotid artery injury model in vivo. ACATS could rapidly interact with blood and its components, including platelets (PLs), red blood cells (RBCs), and coagulation factors, resulting in these blood components rapidly accumulation and the following thrombus formation and coagulation factors activation.


Assuntos
Quitosana , Hemostáticos , Animais , Coelhos , Quitosana/química , Quitosana/farmacologia , Hemostáticos/uso terapêutico , Hemostáticos/química , Hemostáticos/farmacologia , Hemostasia , Compostos de Silício/farmacologia
18.
Bioorg Med Chem Lett ; 22(4): 1664-9, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22264474

RESUMO

To synthesise and characterize the polyoxometalate Cs(2)K(4)Na[SiW(9)Nb(3)O(40)]·H(2)O 1 for its anti-hepatitis B virus (HBV) properties by using the HepG2.2.15 cell. The methylthiazol tetrazolium assay was used to evaluate the growth inhibitory effect of Compound 1 on HepG2.2.15 cell. By using ELISA and real-time PCR, respectively, the presence of extracellular hepatitis B surface antigen (HBsAg), e antigen (HBeAg), and HBV DNA were measured. The levels of intracellular HBV DNA and mRNA were determined by using Southern blot or reverse-transcription-PCR, respectively. Intracellular distribution of antigen were measured by Western blot. A 1995 µmol/L concentration of the commercially-available hepatitis B drug, adefovir dipivoxil (ADV), was required to achieve 50% cytotoxicity against cultured cells (CC(50)) by day nine; in contrast, only 1747 µmol/L of Compound 1 was required for the same result. Treatment of HepG2.2.15 cells with Compound 1 effectively suppress the secretion of HBV antigens and HBV DNA in a dose-dependent and time-dependent manner. IC(50) values were determined to be 80 µmol/L for HBsAg, 75 µmol/L for HBeAg and 3.72 µmol/L for supernatant HBV DNA at day nine post-exposure, as opposed to 266, 296, 30.09 µmol/L, respectively, for ADV. Intracellular HBV DNA, mRNA and antigen were also found to be decreased by Compound 1. The same dose of ADV yielded a significantly less robust inhibitory effect. Compound 1 can clear HBV from hepatic cells and may represent a therapeutic agent to treat HBV infection.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Nióbio/química , Compostos de Silício/síntese química , Compostos de Silício/farmacologia , Compostos de Tungstênio/síntese química , Compostos de Tungstênio/farmacologia , Antivirais/química , Linhagem Celular , Cristalografia por Raios X , Humanos , Compostos de Silício/química , Compostos de Tungstênio/química
19.
Inorg Chem ; 51(2): 812-21, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22191427

RESUMO

Two axially ligated rhodamine-Si(IV)-phthalocyanine (Rh-SiPc) conjugates, bearing one and two rhodamine B, were synthesized and their linear and two-photon photophysical, subcellular localization and photocytotoxic properties were studied. These Rh-SiPc conjugates exhibited an almost exclusive mitochondrial localizing property in human nasopharyngeal carcinoma (HK-1) cells and human cervical carcinoma (HeLa) cells. Strong photocytotoxic but low dark cytotoxic properties were also observed for the two Rh-SiPc conjugates toward the HK-1 cells. Using nuclei staining method and flow cytometric DNA content analysis, apoptotic cell death was induced by these conjugates upon photoactivation. This observation is consistent with their mitochondrial localization property. The observed properties of these conjugates qualify them as promising PDT agents.


Assuntos
Indóis/química , Mitocôndrias/efeitos dos fármacos , Fotoquimioterapia/métodos , Rodaminas/química , Compostos de Silício/química , Compostos de Silício/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma , Linhagem Celular Tumoral , Células HeLa/efeitos dos fármacos , Humanos , Isoindóis , Espectroscopia de Ressonância Magnética , Mitocôndrias/metabolismo , Estrutura Molecular , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Compostos de Silício/síntese química , Oxigênio Singlete/metabolismo
20.
Mater Sci Eng C Mater Biol Appl ; 127: 112241, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34225881

RESUMO

Orthopedic implant is commonly associated with occurrence or relapse of osteomyelitis. This study developed a hydrofluoric acid (HF) cleaned silicon nitride (Si3N4) implant Si3N4_AC for osteomyelitis control and established a rat tibial osteomyelitis model to evaluate its efficacy on eradicating periprosthetic infection and enhancing bone regeneration. In vitro studies revealed Si3N4_AC had improved biocompatibility and inhibited Staphylococcus aureus adhesion. A custom-made Si3N4_AC implant was prepared and inserted into the rat tibia longitudinal cavity inoculated with Staphylococcus aureus. The in vivo bacteriostatic and osteogenic efficacies of Si3N4_AC implant were evaluated by histological, microbiological and Micro-CT analyses and compared with implants of pure Ti and Si3N4 . Si3N4_AC implant group revealed 99.5% inhibition of periprosthetic Staphylococcus aureus compared to the osteomyelitis group after 14 days post-operation. Implant-adhering bacteria density of Si3N4_AC was also much lower than pure Ti and Si3N4. In addition, micro-CT evaluation of peri-implant bone formation under the condition of periprosthetic osteomyelitis after 30 days post-surgery confirmed the osteogenic ability of Si3N4_AC. Taken together, Si3N4_AC can be an effective orthopedic biomaterial to eradicate periprosthetic infection and enhance bone regeneration.


Assuntos
Osteomielite , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Regeneração Óssea , Modelos Animais de Doenças , Ácido Fluorídrico , Osteomielite/tratamento farmacológico , Próteses e Implantes , Ratos , Compostos de Silício/farmacologia , Infecções Estafilocócicas/tratamento farmacológico
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