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1.
Molecules ; 26(4)2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33670043

RESUMEN

The aim of this study was to investigate and understand bacterial adhesion to different dental material surfaces like amalgam, Chromasit, an Co-Cr alloy, an IPS InLine ceramic, yttrium stabilized tetragonal polycrystalline zirconia (TPZ), a resin-based composite, an Au-Pt alloy, and a tooth. For all materials, the surface roughness was assessed by profilometry, the surface hydrophobicity was determined by tensiometry, and the zeta potential was measured by electrokinetic phenomena. The arithmetic average roughness was the lowest for the TPZ ceramic (Ra = 0.23 µm ± 0.02 µm), while the highest value was observed for the Au-Pt alloy (Ra = 0.356 µm ± 0.075 µm). The hydrophobicity was the lowest on the TPZ ceramic and the highest on the Co-Cr alloy. All measured streaming potentials were negative. The most important cause of tooth caries is the bacterium Streptococcus mutans, which was chosen for this study. The bacterial adhesion to all material surfaces was determined by scanning electron microscopy. We showed that the lowest bacterial extent was on the amalgam, whereas the greatest extent was on tooth surfaces. In general, measurements showed that surface properties like roughness, hydrophobicity and charge have a significant influence on bacterial adhesion extent. Therefore, dental material development should focus on improving surface characteristics to reduce the risk of secondary caries.


Asunto(s)
Aleaciones/química , Cerámica/química , Resinas Compuestas/química , Amalgama Dental/química , Metacrilatos/química , Streptococcus mutans/crecimiento & desarrollo , Uretano/química , Adhesión Bacteriana , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Propiedades de Superficie
2.
Water Res ; 196: 117037, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33751976

RESUMEN

The establishment of a sessile community is believed to occur in a sequence of steps where genetically distinct bacteria can become attached to partner cells via specific molecules, in a process known as coaggregation. The presence of bacteria with the ability to autoaggregate and coaggregate has been described for diverse aquatic systems, particularly freshwater, drinking water, wastewater, and marine water. In these aquatic systems, coaggregation already demonstrated a role in the development of complex multispecies sessile communities, including biofilms. While specific molecular aspects on coaggregation in aquatic systems remain to be understood, clear evidence exist on the impact of this mechanism in multispecies biofilm resilience and homeostasis. The identification of bridging bacteria among coaggregating consortia has potential to improve the performance of wastewater treatment plants and/or to contribute for the development of strategies to control undesirable biofilms. This study provides a comprehensive analysis on the occurrence and role of bacterial coaggregation in diverse aquatic systems. The potential of this mechanism in water-related biotechnology is further described, with particular emphasis on the role of bridging bacteria.


Asunto(s)
Bacterias , Adhesión Bacteriana , Bacterias/genética , Biopelículas , Agua Dulce
3.
Int J Nanomedicine ; 16: 1509-1523, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33658781

RESUMEN

Purpose: The study was intended to create a uniform zirconia layer even on the surface of complex structures via atomic layer deposition (ALD). The impact of crystalline zirconia deposited by ALD on bacterial adhesion and osteoblast viability was assessed via surface treatment of dental implants. Methods: Amorphous zirconia was deposited using an atomic layer deposition reactor (Atomic Classic, CN1, Hwaseong, Korea) on titanium discs. Heating the samples at 400°C resulted in crystallization. Samples were divided into three groups: the control group, the group carrying amorphous ALD-zirconia (Z group), and the heat-treated group following zirconia ALD deposition (ZH group).The surface of each sample was analyzed, followed by the assessment of adhesion of Streptococcus mutans and Porphyromonas gingivalis, and viability and differentiation of MC3T3-E1 cells. Results: The adhesion of S. mutans and P. gingivalis was significantly reduced in the Z and ZH groups compared with the control group (P < 0.05). The viability of MC3T3-E1 cells was significantly increased in the ZH group compared with the control group (P < 0.001), while no significant differences were observed in the Z group (P > 0.05). Differentiation of MC3T3-E1 cells showed a marginally significant increase in the ZH group compared with the control group (P < 0.1), while no significant differences were found in the Z group (P > 0.1). Conclusion: Compared with the pure titanium group, the groups that were coated with zirconia via ALD showed a decreased adhesion of S. mutans during the early stages of biofilm formation and P. gingivalis adhesion inducing peri-implantitis, and an increase in MC3T3-E1 cell viability and differentiation. The findings indicate the possibility of treating the implant surface to reduce peri-implantitis and improve osseointegration.


Asunto(s)
Adhesión Bacteriana , Osteoblastos/citología , Titanio/farmacología , Circonio/química , Animales , Adhesión Bacteriana/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Ratones , Microscopía de Fuerza Atómica , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/ultraestructura , Espectroscopía de Fotoelectrones , Espectrometría por Rayos X , Propiedades de Superficie , Difracción de Rayos X
4.
Methods Mol Biol ; 2291: 253-272, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33704757

RESUMEN

Therapeutic antibodies (Abs) inhibiting bacterial adhesion to host epithelia are an attractive option to reduce the load of Shiga toxin-producing E. coli (STEC) in the intestine of the patient and also in the bovine reservoir, thereby minimizing the risk of STEC contamination in the food chain. Of particular interest are recombinant single-domain Ab fragments called nanobodies (Nbs) derived from the variable domain of camelid heavy chain-only antibodies (VHH). The outer membrane adhesin intimin and the translocated intimin receptor (Tir) are essential for the attachment of STEC to host epithelia. In addition, EspA filaments of the bacterial type III protein secretion system are needed for Tir translocation into the host cell. Given their importance for bacterial adhesion and colonization, we developed Nbs against intimin, Tir and EspA proteins of STEC serotype O157:H7. Here, we report the screening methods used to isolate inhibitory Nbs blocking intimin-Tir protein-protein interaction, actin-pedestal formation, and intimate adhesion of STEC to epithelial cells in vitro. First, we describe how VHH gene repertoires can be produced as Nbs secreted by E. coli using the α-hemolysin (HlyA) protein secretion system. Next, we report the methods for identification of inhibitors of intimin-Tir protein-protein interaction and of STEC intimate adhesion to HeLa cells in culture. These methods can be adapted for the screening of Nbs against different adhesin-receptor complexes to block the adhesion of other pathogens to host cells.


Asunto(s)
Adhesinas Bacterianas/inmunología , Anticuerpos Antibacterianos/inmunología , Adhesión Bacteriana/inmunología , Células Epiteliales , Escherichia coli O157/inmunología , Proteínas de Escherichia coli/inmunología , Receptores de Superficie Celular/inmunología , Anticuerpos de Dominio Único/inmunología , Animales , Bovinos , Células Epiteliales/inmunología , Células Epiteliales/microbiología , Escherichia coli O157/patogenicidad , Humanos
5.
Nat Commun ; 12(1): 1625, 2021 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-33712575

RESUMEN

Many bacterial pathogens use a type III secretion system (T3SS) to manipulate host cells. Protein secretion by the T3SS injectisome is activated upon contact to any host cell, and it has been unclear how premature secretion is prevented during infection. Here we report that in the gastrointestinal pathogens Yersinia enterocolitica and Shigella flexneri, cytosolic injectisome components are temporarily released from the proximal interface of the injectisome at low external pH, preventing protein secretion in acidic environments, such as the stomach. We show that in Yersinia enterocolitica, low external pH is detected in the periplasm and leads to a partial dissociation of the inner membrane injectisome component SctD, which in turn causes the dissociation of the cytosolic T3SS components. This effect is reversed upon restoration of neutral pH, allowing a fast activation of the T3SS at the native target regions within the host. These findings indicate that the cytosolic components form an adaptive regulatory interface, which regulates T3SS activity in response to environmental conditions.


Asunto(s)
Citosol/metabolismo , Transporte de Proteínas/fisiología , Sistemas de Secreción Tipo III/metabolismo , Adhesión Bacteriana , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Concentración de Iones de Hidrógeno , Shigella flexneri/metabolismo , Sistemas de Secreción Tipo III/genética , Yersinia enterocolitica/metabolismo
6.
Nat Commun ; 12(1): 1140, 2021 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-33602902

RESUMEN

Clostridioides difficile spores produced during infection are important for the recurrence of the disease. Here, we show that C. difficile spores gain entry into the intestinal mucosa via pathways dependent on host fibronectin-α5ß1 and vitronectin-αvß1. The exosporium protein BclA3, on the spore surface, is required for both entry pathways. Deletion of the bclA3 gene in C. difficile, or pharmacological inhibition of endocytosis using nystatin, leads to reduced entry into the intestinal mucosa and reduced recurrence of the disease in a mouse model. Our findings indicate that C. difficile spore entry into the intestinal barrier can contribute to spore persistence and infection recurrence, and suggest potential avenues for new therapies.


Asunto(s)
/fisiología , Infecciones por Clostridium/microbiología , Células Epiteliales/microbiología , Células Epiteliales/patología , Intestinos/microbiología , Intestinos/patología , Esporas Bacterianas/fisiología , Animales , Adhesión Bacteriana/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Línea Celular , /ultraestructura , Colágeno/metabolismo , Endocitosis , Células Epiteliales/ultraestructura , Femenino , Fibronectinas/metabolismo , Humanos , Integrinas/metabolismo , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Masculino , Ratones Endogámicos C57BL , Nistatina/farmacología , Unión Proteica/efectos de los fármacos , Recurrencia , Esporas Bacterianas/efectos de los fármacos , Esporas Bacterianas/ultraestructura , Ácido Taurocólico/farmacología , Vitronectina/metabolismo
7.
Vet Microbiol ; 255: 109017, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33639390

RESUMEN

Bovine coronavirus (BCoV) is one of the agents causing bovine respiratory disease complex (BRDC), with single infection tending to be mild to moderate; the probability of developing pneumonia in BRDC may be affected by viral and bacterial combinations. Previously, we reported that bovine respiratory syncytial virus (BRSV) infection enhances adherence of Pasteurella multocida (PM) to cells derived from the bovine lower respiratory tract but that BRSV infection in cells derived from the upper respiratory tract reduces PM adherence. In this study, we sought to clarify whether the modulation of bacterial adherence to cells derived from the bovine upper and lower respiratory tract is shared by other BRDC-related viruses by infecting bovine epithelial cells from the trachea, bronchus and lung with BCoV and/or PM. The results showed that cells derived from both the upper and lower respiratory tract were susceptible to BCoV infection. Furthermore, all cells infected with BCoV exhibited increased PM adherence via upregulation of two major bacterial adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and platelet-activating factor receptor (PAF-R), suggesting that compared with BRSV infection, BCoV infection differentially modulates bacterial adherence. In summary, we identified distinct interaction between bovine respiratory viruses and bacterial infections.


Asunto(s)
Adhesión Bacteriana/fisiología , Coronavirus Bovino/fisiología , Mucosa Respiratoria/metabolismo , Animales , Western Blotting , Bovinos , Humanos , Mucosa Nasal/virología , Receptores de Superficie Celular/metabolismo , Mucosa Respiratoria/microbiología , Mucosa Respiratoria/virología , Células Tumorales Cultivadas , Regulación hacia Arriba
8.
Water Sci Technol ; 83(4): 877-885, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33617494

RESUMEN

Attachment and separation of sulfate-reducing bacteria (SRB) biofilm on stainless steel (SS) in simulated cooling water with and without different sterilization treatments was investigated by calculation of surface energy, theoretical work of adhesion and analysis of Scanning Electron Microscope/Energy Dispersive Spectrometer. Two types of biocides, glutaraldehyde and Polyhexamethylene guanidine (PHMG), and electromagnetic treatment were used in this paper. The results show that PHMG had the best bactericidal performance, followed by glutaraldehyde, and electromagnetic treatment was the lowest one. The theoretical work of adhesion was used to quantitatively evaluate the adhesion of biofilm on the surface of the metal. Theoretical work of adhesion between biofilm and SS in simulated cooling water increased with time. The theoretical adhesion work and adhesive capacity of biofilm to SS surface increased after treating with glutaraldehyde while decreasing after treating with PHMG and electromagnetic field. As the theoretical adhesion work decreased, the biofilm was gradually removed from the stainless steel surface. On the contrary, the biofilm adhered more firmly. The results of SEM were also consistent with the calculation results of theoretical adhesion work. The results obtained indicated that electromagnetic treatment had the lowest effect in sterilization but the best in biofilm separation.


Asunto(s)
Desinfectantes , Acero Inoxidable , Adhesión Bacteriana , Biopelículas , Desinfección , Propiedades de Superficie
9.
Monogr Oral Sci ; 29: 155-194, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33427213

RESUMEN

Biofilm formation depends on many factors, one of them being the surface (substrate) on which the biofilm is formed, and dental restorative materials are such substrates. Biofilms play a crucial role for caries formation and inflammation of gingival, periodontal, or mucosal tissues next to restorations. Even general health problems such as systemic infections in immunocompromised patients may result from biofilms on dental materials (e.g., on dentures). Furthermore, biofilms may change material or surface properties. Biofilms on restorative materials have been investigated by several in vitro, in situ, and in vivo methods measuring a large number of different endpoints. Basically, datasets obtained from different methodological approaches are most suitable for final assessments. While surface properties like wettability or surface free energy (SFE) influence biofilm formation to a certain extent, the most relevant surface properties are material roughness followed by surface chemistry. The pellicle, which is formed rapidly on restorations after in vivo exposure, masks or levels off the influence of surface properties like wettability or SFE on biofilm formation. The prevention of biofilm formation is mainly based on general oral hygiene regimens. Furthermore, optimal polishing of restorative materials is instrumental. Several antimicrobial substances have been incorporated into restorative materials, which act by being released or as surface repellents. However, the optimal biofilm-preventive restorative material has not been found so far. New approaches in this context should aim at: (1) better understanding the role of the biofilm matrix (extracellular polymeric substance), and (2) implementing ecology-based approaches for the modification of dysbiotic disease-associated biofilms.


Asunto(s)
Adhesión Bacteriana , Matriz Extracelular de Sustancias Poliméricas , Biopelículas , Materiales Dentales , Película Dental , Humanos
10.
Carbohydr Polym ; 256: 117524, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33483045

RESUMEN

Curdlan hydrogel obtained after thermal gelling exhibits elasticity and high water-absorbing capacity. However, its modifications leading to the increase of biofunctionality usually alter its solubility and reduce mechanical parameters. Therefore, curdlan hydrogel was modified by deposition of polydopamine to improve its capacity to bind biologically active molecules with free amino groups. It exhibited the unchanged structure, mechanical properties and increased soaking capacity. Aminoglycoside antibiotic (gentamicin) as a model molecule was effectively immobilized to such modified curdlan via quinone moiety (but not amino groups) of polydopamine. Approximately 50 % of the immobilized drug was released following Fickian diffusion and inhibited the bacterial growth in matrix-surrounding medium in prolonged manner. The remaining drug amount was stably attached and prevented the hydrogel against bacterial adhesion even when all the mobile drug has been released. Therefore, polydopamine-modified curdlan hydrogel shows the potential for fabrication of functional materials for different purposes, including drug-loaded biomaterials.


Asunto(s)
Antibacterianos/metabolismo , Materiales Biocompatibles Revestidos/síntesis química , Gentamicinas/metabolismo , Hidrogeles/síntesis química , Indoles/química , Polímeros/química , beta-Glucanos/química , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Portadores de Fármacos , Composición de Medicamentos/métodos , Liberación de Fármacos , Elasticidad , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Gentamicinas/farmacología , Humanos , Hidrogeles/farmacología , Cinética , Pruebas de Sensibilidad Microbiana , Solubilidad , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus epidermidis/efectos de los fármacos , Staphylococcus epidermidis/crecimiento & desarrollo , Humectabilidad
11.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33401545

RESUMEN

Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.


Asunto(s)
Materiales Biocompatibles/farmacología , Biopelículas/efectos de los fármacos , Resinas Compuestas/química , Materiales Dentales/farmacología , Boca/efectos de los fármacos , Polímeros/química , Impresión Tridimensional/instrumentación , Adhesión Bacteriana , Biopelículas/crecimiento & desarrollo , Humanos , Ensayo de Materiales , Metacrilatos/química , Boca/microbiología , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/metabolismo
12.
New Microbiol ; 44(1): 42-50, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33453704

RESUMEN

This work aims to assess the in vitro adhesion of two type strains of Lactobacillus plantarum (ATCC 14917 and ATCC BAA-793) (now Lactiplantibacillus plantarum). The experiments were conducted both in vitro on colon cells lines (Caco-2 and HT-29) and in vivo by adopting Galleria mellonella, a well-known alternative preclinical model. Data comparison obtained from in vitro and in vivo assays showed that adhesion performance is comparable in both models. Moreover, the type strain BAA-793, originally isolated from human saliva, showed enhanced adhesion performance, either in vitro to the low mucus-producing cell line (HT-29) or in vivo into the G mellonella gut. These results suggest a possible adaptation of this strain to its ecological niche compared to ATCC 14917. This preliminary pilot study, once again, showed the reliability of G. mellonella oral administration model as a first-line screening tool for in vitro to in vivo translation. Also, for the first time, the permanence of Lactobacillus strains into G. mellonella gut has been reported, reinforcing the claim that this preclinical model can be used, together with standardised in vitro and in vivo procedures already accepted across the scientific community, for the evaluation and investigation of new potential probiotic strains.


Asunto(s)
Lactobacillus plantarum , Lepidópteros , Probióticos , Administración Oral , Animales , Adhesión Bacteriana , Células CACO-2 , Humanos , Proyectos Piloto , Reproducibilidad de los Resultados
13.
J Med Microbiol ; 70(3)2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33492206

RESUMEN

Introduction. Staphylococcus epidermidis is predominant in implant-associated infections due to its capability to form biofilms. It can deploy several strategies for biofilm development using either polysaccharide intercellular adhesin (PIA), extracellular DNA (eDNA) and/or proteins, such as the extracellular matrix-binding protein (Embp).Hypothesis/Gap Statement. We hypothesize that the dichotomic regulation of S. epidermidis adhesins is linked to whether it is inside a host or not, and that in vitro biofilm investigations in laboratory media may not reflect actual biofilms in vivo.Aim. We address the importance of PIA and Embp in biofilm grown in 'humanized' media to understand if these components play different roles in biofilm formation under conditions where bacteria can incorporate host proteins in the biofilm matrix.Methodology. S. epidermidis 1585 WT (deficient in icaADBC), and derivative strains that either lack embp, express embp from an inducible promotor, or express icaADBC from a plasmid, were cultivated in standard laboratory media, or in media with human plasma or serum. The amount, structure, elasticity and antimicrobial penetration of biofilms was quantified to describe structural differences caused by the different matrix components and growth conditions. Finally, we quantified the initiation of biofilms as suspended aggregates in response to host factors to determine how quickly the cells aggregate in response to the host environment and reach a size that protects them from phagocytosis.Results. S. epidermidis 1585 required polysaccharides to form biofilm in laboratory media. However, these observations were not representative of the biofilm phenotype in the presence of human plasma. If human plasma were present, polysaccharides and Embp were redundant for biofilm formation. Biofilms formed in human plasma were loosely attached and existed mostly as suspended aggregates. Aggregation occurred after 2 h of exposing cells to plasma or serum. Despite stark differences in the amount and composition of biofilms formed by polysaccharide-producing and Embp-producing strains in different media, there were no differences in vancomycin penetration or susceptibility.Conclusion. We suggest that the assumed importance of polysaccharides for biofilm formation is an artefact from studying biofilms in laboratory media void of human matrix components. The cell-cell aggregation of S. epidermidis can be activated by host factors without relying on either of the major adhesins, PIA and Embp, indicating a need to revisit the basic question of how S. epidermidis deploys self-produced and host-derived matrix components to form antibiotic-tolerant biofilms in vivo.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Polisacáridos Bacterianos/metabolismo , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/fisiología , Adhesión Bacteriana , Regulación Bacteriana de la Expresión Génica , Humanos
14.
Arch Oral Biol ; 122: 105022, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33418434

RESUMEN

The objective of this study was to perform a comprehensive review of the use of antimicrobial peptides for the prevention and treatment of dental caries. The study included publications in the English language that addressed the use of antimicrobial peptides in the prevention and treatment of caries. These publications were also searchable on PubMed, Web of Science, Embase, Scopus, the Collection of Anti-Microbial Peptides and the Antimicrobial Peptide Database. A total of 3,436 publications were identified, and 67 publications were included. Eight publications reported seven natural human antimicrobial peptides as bactericidal to Streptococcus mutans. Fifty-nine publications reported 43 synthetic antimicrobial peptides developed to mimic natural antimicrobial peptides, fusing peptides with functional sequences and implementing new designs. The 43 synthetic antimicrobial peptides were effective against Streptococcus mutans, and nine peptides specifically targeted Streptococcus mutans. Ten antimicrobial peptides had an affinity for hydroxyapatite to prevent bacterial adhesion. Six antimicrobial peptides were also antifungal. Four antimicrobial peptides promoted remineralisation or prevented the demineralisation of teeth by binding calcium to hydroxyapatite. In conclusion, this study identified 67 works in the literature that reported seven natural and 43 synthetic antimicrobial peptides for the prevention and treatment of caries. Most of the antimicrobial peptides were bactericidal, and some prevented bacterial adhesion. A few antimicrobial peptides displayed remineralising properties with hydroxyapatite.


Asunto(s)
Antibacterianos/uso terapéutico , Caries Dental , Proteínas Citotóxicas Formadoras de Poros/uso terapéutico , Adhesión Bacteriana/efectos de los fármacos , Biopelículas , Caries Dental/tratamiento farmacológico , Caries Dental/prevención & control , Durapatita , Humanos , Streptococcus mutans/efectos de los fármacos , Remineralización Dental
15.
ACS Appl Mater Interfaces ; 13(4): 4874-4885, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33464809

RESUMEN

This work is strategically premeditated to study the potential of a herbal medicinal product as a natural bioactive ingredient to generate nanocellulose-based antibacterial architectures. In situ fibrillation of purified cellulose was done in cinnamon extract (ciE) to obtain microfibrillated cellulose (MFC). To this MFC suspension, carboxylated cellulose nanocrystals (cCNCs) were homogeneously mixed and the viscous gel thus obtained was freeze-dried to obtain lightweight and flexible composite aerogel architectures impregnated with ciE, namely, ciMFC/cCNCs. At an optimal concentration of 0.3 wt % cCNCs (i.e., for ciMFC/cCNCs_0.3), an improvement of around 106% in compressive strength and 175% increment in modulus were achieved as compared to pristine MFC architecture. The efficient loading and interaction of ciE components, specifically cinnamaldehyde, with MFC and cCNCs resulted in developing competent antibacterial surfaces with dense and uniform microstructures. Excellent and long-term antimicrobial activity of the optimized architectures (ciMFC/cCNCs_0.3) was confirmed through various antibacterial assays like the zone inhibition method, bacterial growth observation at OD600, minimum inhibitory concentration (MIC, here 1 mg/mL), minimum bactericidal concentration (MBC, here 3-5 mg/mL), and Live/Dead BacLight viability tests. The changes in the bacterial morphology with a disrupted membrane were further confirmed through various imaging techniques like confocal laser scanning microscopy, FESEM, AFM, and 3D digital microscopy. The dry composite architecture showed the persuasive capability of suppressing the growth of airborne bacteria, which in combination with antibacterial efficiency in the wet state is considered as an imperative aspect for a material to act as the novel biomaterial. Furthermore, these architectures demonstrated excellent antibacterial performance under real "in use" contamination prone conditions. Hence, this work provides avenues for the application of crude natural extracts in developing novel forms of advanced functional biomaterials that can be used for assorted biological/healthcare applications such as wound care and antimicrobial filtering units.


Asunto(s)
Acroleína/análogos & derivados , Antibacterianos/química , Celulosa/química , Cinnamomum aromaticum/química , Nanogeles/química , Extractos Vegetales/química , Acroleína/química , Acroleína/farmacología , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Infecciones Bacterianas/prevención & control , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología
16.
ACS Appl Mater Interfaces ; 13(4): 5478-5485, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33492929

RESUMEN

Biofilms which are self-organized communities can contaminate various infrastructural systems. Preventing bacterial adhesion on surfaces is more desirable than cleaning or disinfection of bacteria-contaminated surfaces. In this study, a 24 h bacterial adhesion test showed that "slippery surfaces" had increased resistance to bacterial contamination compared to polydimethylsiloxane and superhydrophobic surfaces. However, it did not completely inhibit bacterial attachment, indicating that it only retards surface contamination by bacteria. Hence, a strategy of killing bacteria with minimal bacterial adhesion was developed. A crystal violet-impregnated slippery (CVIS) surface with bactericidal and slippery features was produced through a simple dipping process. The CVIS surface had a very smooth and lubricated surface that was highly repellent to water and blood contamination. Bactericidal tests against Escherichia coli and Staphylococcus aureus showed that the CVIS surface exhibited bactericidal activity in dark and also showed significantly enhanced bactericidal activity (>3 log reduction in bacteria number) in white light.


Asunto(s)
Antiinfecciosos Locales/farmacología , Adhesión Bacteriana/efectos de los fármacos , Incrustaciones Biológicas/prevención & control , Violeta de Genciana/farmacología , Antiinfecciosos Locales/administración & dosificación , Infecciones Bacterianas/prevención & control , Biopelículas/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Violeta de Genciana/administración & dosificación , Humanos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Propiedades de Superficie
17.
ACS Appl Mater Interfaces ; 13(2): 2303-2315, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33395246

RESUMEN

Numerous studies have found that the surface topography affects the material antibacterial properties by reducing the attachment of bacteria on the surfaces without influencing the viability of the adhered cells. For Cu-bearing alloys with excellent contact-killing properties, bacterial adhesion on the surface is also accompanied by short-range interactions which regulate the toxic effects of the material surface against bacterial cells. Thus, the surface topography of Cu-bearing alloys, as an important factor dominating the exposure level of bacteria on the surfaces, should affect the subsequent contact-killing efficiency. In this work, our major focus was on the regulation mechanism of the surface features on the material-bacterial interactions. We correlated the surface properties including different surface roughnesses of Cu-bearing stainless steel (SS) with the bacterial damage pattern and attempted to clarify the role of surface roughness in mediating the contact-killing behavior of Cu-bearing SS. The results of both atomic force microscopy and scanning electron microscopy investigations showed that E. coli cells experienced the most rapid physical and mechanical damages after incubating with the diamond-polished Cu-bearing SS surface. The bacterial cells noticeably stiffened and the adhesion force significantly increased, as evidenced by force-distance curve measurements. Because of the enhanced hydrophobicity and higher surface potential of the diamond-polished surface, which strengthened the Lewis acid-base attractive forces and weakened the electrostatic barrier between the bacteria and the surface, a higher exposure surface for bacteria was generated. Furthermore, the contact-induced charge transfer, manifested by Cu ion burst release, and reactive oxygen species overexpression contribute to an efficient contact-killing process.


Asunto(s)
Antibacterianos/farmacología , Cobre/farmacología , Escherichia coli/efectos de los fármacos , Acero Inoxidable/farmacología , Aleaciones/química , Aleaciones/farmacología , Antibacterianos/química , Adhesión Bacteriana/efectos de los fármacos , Cobre/química , Escherichia coli/fisiología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/prevención & control , Humanos , Acero Inoxidable/química , Propiedades de Superficie
18.
ACS Appl Mater Interfaces ; 13(2): 3089-3097, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33400490

RESUMEN

Numerous efforts to fabricate antimicrobial surfaces by simple yet universal protocols with high efficiency have attracted considerable interest but proved to be particularly challenging. Herein, we designed and fabricated a series of antimicrobial polymeric coatings with different functions from single to multiple mechanisms by selectively utilizing diethylene glycol diglycidyl ether (PEGDGE), polylysine, and poly[glycidylmethacrylate-co-3-(dimethyl(4-vinylbenzyl)ammonium)propyl sulfonate] (poly(GMA-co-DVBAPS)) via straightforward mussel-inspired codeposition techniques. Bactericidal polylysine endowed the modified surfaces with a high ability (∼90%) to kill attached bacteria, while PEGDGE components with unique surface hydration prevented bacterial adhesion, avoiding the initial biofilm formation. Moreover, excellent salt-responsive poly(GMA-co-DVBAPS) enabled reactant polymeric coatings to change chain conformations from shrinkable to stretchable state and subsequently release >90% attached bacteria when treated with NaCl solution, even after repeated cycles. Therefore, the obtained polymeric coatings, polydopamine/poly(GMA-co-DVBAPS) (PDA/PDV), polydopamine/polylysine/poly(GMA-co-DVBAPS) (PDA/l-PDV), and polydopamine/polylysine/poly(GMA-co-DVBAPS)/diethylene glycol diglycidyl ether (PDA/l-PDV-PEGDGE), controllably realized functions from single and dual to multiple antimicrobial mechanisms, as evidenced by long-term antifouling activity to bacteria, high bactericidal efficiency, and salt-responsive bacterial regeneration performance with several bacterial killing-release cycles. This study not only contributes to mussel-inspired chemistry for polymeric coatings with controllable functions but also provides a series of reliable and highly efficient antimicrobial surfaces for potential biomedical applications.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Polímeros/química , Polímeros/farmacología , Animales , Adhesión Bacteriana/efectos de los fármacos , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/prevención & control , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Bivalvos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/fisiología , Glicoles de Etileno/química , Glicoles de Etileno/farmacología , Humanos , Indoles/química , Indoles/farmacología , Polilisina/química , Polilisina/farmacología , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Propiedades de Superficie
19.
Gene ; 773: 145415, 2021 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-33444678

RESUMEN

Heat shock protein 27 (HSP27) plays an important role in protecting cells from various stress factors. This study aimed to investigate the function of HSP27 gene and its regulatory mechanism as infected by Escherichia coli (E. coli) at the tissue and cellular levels. Real-time PCR was used to detect the differential expression of HSP27 gene in F18 resistant and sensitive Sutai pigs and the differential expression upon E. coli F18ab, F18ac, K88ac bacterial supernatant, thallus infection and LPS induction in IPEC-J2. In addition, the HSP27 gene overexpression vector was constructed to detect the effect of the HSP27 gene overexpression on the adhesion of E. coli F18 to IPEC-J2, secretion of pro-inflammatory factors, and the expression of the upstream key genes in Mitogen-activated protein kinase (MAPK) pathway. Ribosomal S6 kinase (RSK2) is an important protein in the MAPK pathway. Therefore, the RSK2 gene overexpression vector was constructed and the number of colonies was counted after co-transfection of HSP27 and RSK2 gene. Results revealed that the expression level of HSP27 gene in resistant individuals in 11 tissues was higher than sensitive type. At the cellular level, the relative expression levels of HSP27 gene were increased after F18ab, F18ac bacterial supernatant, F18ab thallus infection, and LPS induction for 4 h (P < 0.01). The adhesion ability of E. coli F18ab to IPEC-J2 was significantly reduced after HSP27 gene overexpression (P < 0.01), and the concentration of pro-inflammatory factors in the HSP27 gene overexpression group was significantly reduced compared with the control group after F18ab infection (P < 0.05). Furthermore, the expression of RSK2 was significantly increased in HSP27 overexpression group upon F18ab infection (P < 0.01). The colonies quantitative results also showed that the number of colonies was significantly reduced after co-transfection of HSP27 and RSK2 gene. We indicated that the high expression of HSP27 gene may resist the inflammatory response caused by exogenous stress and enhance the ability of IPEC-J2 to resist E. coli F18 infection. RSK2 gene in the MAPK pathway may cooperate with HSP27 gene to participate in the immune response of the organism, which provides a theoretical basis for the study of the mechanism of anti-E. coli infection in piglets.


Asunto(s)
Resistencia a la Enfermedad/genética , Infecciones por Escherichia coli/genética , Escherichia coli/genética , Proteínas de Choque Térmico HSP27/genética , Animales , Adhesión Bacteriana/genética , Diarrea/genética , Diarrea/microbiología , Diarrea/veterinaria , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Proteínas de Escherichia coli/genética , Regulación de la Expresión Génica/genética , Porcinos/genética , Porcinos/microbiología , Enfermedades de los Porcinos/genética , Enfermedades de los Porcinos/microbiología
20.
Carbohydr Polym ; 252: 117138, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33183597

RESUMEN

Bacterial adhesion infection caused by medical materials in clinical application has become a serious threat, and it urgently needs new strategies to deal with these clinical challenges. In this work, LED209, a highly selective histidine sensor kinase inhibitor of Gram-negative bacteria, was covalently attached on cellulose membrane (CM) via click reaction. The data of contact angle measurements, ATR-FTIR and X-ray photoelectron spectroscopy confirmed the successful synthesis of LED-CM. In addition, the results of antibacterial activity of the membranes shown that LED-CM exhibited excellent anti-adhesion ability to Enterohemorrhagic Escherichia coli (EHEC), and significantly reduced the formation of bacterial biofilm. Importantly, LED-CM was able to repress the expression of virulence genes in EHEC. Furthermore, LED209-functionalized cellulose membrane indicated no cytotoxicity to mammalian cells. Hence, our present work demonstrated that CM modified with LED209 possessed markedly anti-adhesion activity against EHEC, which offered a potent antimicrobial material for combating bacterial infections.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/antagonistas & inhibidores , Enzimas Inmovilizadas/farmacología , Infecciones por Escherichia coli/tratamiento farmacológico , Escherichia coli O157/efectos de los fármacos , Proteínas de Escherichia coli/antagonistas & inhibidores , Complejos Multienzimáticos/antagonistas & inhibidores , Sulfonamidas/farmacología , Animales , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Celulosa/química , Membranas Artificiales , Ratones , Células 3T3 NIH
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