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1.
Antibiotics (Basel) ; 12(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38136705

RESUMO

The increasing bacterial drug resistance and the associated challenges in the treatment of infections warrant the search for alternative therapeutic methods. Hope is placed in antimicrobial peptides, which have a broad spectrum of action and are effective against strains which are resistant to conventional antibiotics. Antimicrobial peptides are also tested for their efficacy in the treatment of infections associated with the formation of biofilm. The aim of the present study was to examine the effect of Camel peptide on S. epidermidis and S. haemolyticus adhesion to and formation of biofilm on steel cortical bone screws and also on the process of reducing mature biofilm in orthopedic implants. The tests were performed on steel implants for osteosynthesis. The MIC value and MBEC values of the peptide were determined using the microdilution method in microtiter plates. The effect of the peptide on adhesion and biofilm formation, as well as on the activity on the preformed biofilm, was evaluated using quantitative methods and confocal microscopy. The presented research results indicate that the peptide exhibits very good antimicrobial properties against the analyzed strains. Concentrations above MIC reduced biofilm in the range of 90-99%.

2.
Nutrients ; 14(3)2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35276782

RESUMO

Gut dysbiosis, alongside a high-fat diet and cigarette smoking, is considered one of the factors promoting coronary arterial disease (CAD) development. The present study aimed to research whether gut dysbiosis can increase bacterial metabolites concentration in the blood of CAD patients and what impact these metabolites can exert on endothelial cells. The gut microbiomes of 15 age-matched CAD patients and healthy controls were analyzed by 16S rRNA sequencing analysis. The in vitro impact of LPS and indoxyl sulfate at concentrations present in patients' sera on endothelial cells was investigated. 16S rRNA sequencing analysis revealed gut dysbiosis in CAD patients, further confirmed by elevated LPS and indoxyl sulfate levels in patients' sera. CAD was associated with depletion of Bacteroidetes and Alistipes. LPS and indoxyl sulfate demonstrated co-toxicity to endothelial cells inducing reactive oxygen species, E-selectin, and monocyte chemoattractant protein-1 (MCP-1) production. Moreover, both of these metabolites promoted thrombogenicity of endothelial cells confirmed by monocyte adherence. The co-toxicity of LPS and indoxyl sulfate was associated with harmful effects on endothelial cells, strongly suggesting that gut dysbiosis-associated increased intestinal permeability can initiate or promote endothelial inflammation and atherosclerosis progression.


Assuntos
Disbiose , Indicã , Disbiose/microbiologia , Células Endoteliais , Endotoxinas , Humanos , Indicã/toxicidade , RNA Ribossômico 16S/genética
3.
Acta Bioeng Biomech ; 24(3): 107-118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38314484

RESUMO

PURPOSE: Conventional orthodontic treatment with stainless steel orthodontic wires may be detrimental to oral health, as it contributes to demineralized lesions and increases adhesion and bacterial biofilm formation, which contributes to cavity development. An alternative that has been investigated to reduce the side effects of orthodontic treatment is the use of coating materials with antimicrobial nanoparticles. This study aims to evaluate the antiadherent and antibacterial properties of TiO2-coated and TiO2:Ag-coated stainless steel orthodontic wires against S. mutans bacteria. METHODS: In the sol-gel method, TiO2:Ag thin films were deposited on stainless steel orthodontic wires. Coated archwires were analyzed for their antibacterial and antiadherent properties. The evaluation of Streptococcus mutans adhesion to the orthodontic wires' surface was conducted according to the type of coating used, biofilm formation assay, and measurement of the pH of the bacterial community. RESULTS: In the microbiological test, the TiO2:Ag coatings revealed a statistically significant difference in terms of microbial adhesion and biofilm formation by Streptococcus mutans. The TiO2:Ag coating on stainless steel wire increased pH levels in the saliva environment. CONCLUSIONS: It can be concluded that antimicrobial orthodontic wires coated with silver TiO2 nanoparticles using the sol-gel thin film are a promising choice for improving orthodontic treatment.

4.
Oxid Med Cell Longev ; 2020: 7697851, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299531

RESUMO

BACKGROUND AND AIMS: Inflammatory bowel disease pharmacotherapy, despite substantial progress, is still not satisfactory for both patients and clinicians. In view of the chronic and relapsing disease course and not always effective treatment with adverse effects, attempts to search for new, more efficient, and safer substances are essential and reasonable. This study was designed to elucidate the impact of cornelian cherry iridoid-polyphenolic extract (CE) and loganic acid (LA) on adherent-invasive E. coli growth and adhesion in vitro and to assess the effect of pretreatment with CE or LA on the course of intestinal inflammation in rat experimental colitis compared with sulfasalazine. METHODS: Antibacterial and antiadhesive activities of CE and LA were assessed using microdilution, Int407 cell adherence, and yeast agglutination assays. The colitis model was induced by 2,4,6-trinitrobenzenesulfonic acid. Studied substances were administered intragastrically for 16 days prior to colitis induction. Body weight loss; colon index; histological injuries; IL-23, IL-17, TNF-α, and chemerin levels; and STAT3, Muc2, and TFF3 mRNA expression were evaluated. RESULTS: Only CE exerted antimicrobial and antiadhesive activities in vitro and alleviated colonic symptoms. CE coadministrated with sulfasalazine was more effective than single compounds in reversing increased concentrations of TNF-α, IL-17, and chemerin and decreased Muc2 mRNA expression. CONCLUSIONS: CE exerted a protective effect against experimental colitis via impaired mucosal epithelial barrier restoration and intestinal inflammatory response attenuation and given concomitantly with sulfasalazine counteracted colitis in a more effective way than sulfasalazine alone, which indicates their synergistic interaction. The beneficial effect of CE may also be due to its bacteriostatic and antiadhesive activities.


Assuntos
Antibacterianos/farmacologia , Colite/metabolismo , Colo/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Ácido Trinitrobenzenossulfônico/farmacologia , Animais , Colite/induzido quimicamente , Escherichia coli/metabolismo , Humanos , Inflamação/patologia , Mucosa Intestinal/metabolismo , Iridoides/farmacologia , Masculino , Ratos Wistar , Ácido Trinitrobenzenossulfônico/metabolismo
5.
Adv Clin Exp Med ; 28(7): 899-905, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31066244

RESUMO

BACKGROUND: The relationship of diffusely adherent Escherichia coli (DAEC) with pediatric inflammatory bowel disease (IBD) has not been previously studied. Diffusely adherent E. coli are a common cause of long-lasting childhood diarrhea and we postulated that they may induce inflammation of the intestinal mucosa, contributing to the development of IBD in susceptible children. OBJECTIVES: The aim of the study was to investigate the relationship between DAEC and pediatric IBD, including Crohn's disease (CD) and ulcerative colitis (UC). Diffusely adherent E. coli isolates were also assessed regarding their pathogenicity. MATERIAL AND METHODS: Diffusely adherent E. coli were screened among 130 E. coli strains isolated from intestinal biopsy specimens from 26 children with IBD using polymerase chain reaction (PCR) with primers specific to the pathotype and adherence assays to HEp-2 cells. Diffusely adherent E. coli were further analyzed for their ability to adhere to and invade polarized Caco-2 cells. The immunomodulatory effect of DAEC on the secretion of tumor necrosis factor α (TNF-α) by human monocyte-derived macrophages (MDM) was assessed using an immunoenzymatic assay. RESULTS: Diffusely adherent E. coli were recovered from 18 (69.2%) of the 26 intestinal biopsy specimens from both CD and UC patients. Most DAEC isolates carried AfaE3 adhesin, adhered to and were internalized by Caco-2 cells, and induced secretion of elevated levels of TNF-α. CONCLUSIONS: The study demonstrated the internalization of DAEC by intestinal epithelial cells and their ability to induce secretion of increased level of TNF-α in a Caco-2/macrophage compartmentalized culture. This indicated that the pathovar should be considered a pathobiont inducing inflammation of the intestinal mucosa in pediatric patients with IBD.


Assuntos
Aderência Bacteriana , Moléculas de Adesão Celular/metabolismo , Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Infecções por Escherichia coli/epidemiologia , Escherichia coli/isolamento & purificação , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/microbiologia , Adesinas de Escherichia coli , Células CACO-2 , Moléculas de Adesão Celular/genética , Criança , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/imunologia , Doença de Crohn/epidemiologia , Doença de Crohn/imunologia , Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Polônia/epidemiologia , Prevalência
6.
Int J Med Microbiol ; 309(5): 274-282, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31113736

RESUMO

Amyloid curli fibrils produced by Escherichia coli are well-known virulence factor influencing E. coli adhesion and biofilm formation. However, the impact of curli on intestinal epithelial barrier stimulated with proinflammatory cytokines is unknown. In the study, we examined the effect of curli produced by nonpathogenic E. coli K-12 and wild-type E. coli EC32 strains, and purified CsgA proteins on differentiated Caco-2 cell monolayers stimulated with a mixture of IL-1ß, TNF-α, and INFγ cytokines as a model of 'inflamed intestinal epithelial barrier' in vitro. The results of the study indicated that curliated E. coli adhered better to polarized Caco-2 cells than their curli-deficient mutants and the adherence was further augmented by stimulation of epithelial cells with proinflammatory cytokines. Interestingly, curli reduced internalization but enhanced intracellular survival of the wild-type E. coli strain EC32 within intestinal epithelial cells. Curli-expressing E. coli, as well as purified CsgA proteins, attenuated IL-8 secretion by unstimulated Caco-2 cells, although the effect was barely observed on cytokine-stimulated cells. The findings of the study revealed that curli fibrils are an important virulence factor enabling curliated E. coli to effectively colonize intestinal epithelium especially in individuals with inflammatory intestinal disorders.


Assuntos
Aderência Bacteriana , Citocinas/farmacologia , Células Epiteliais/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/patogenicidade , Intestinos/citologia , Células CACO-2 , Técnicas de Cultura de Células , Células Epiteliais/efeitos dos fármacos , Escherichia coli/genética , Humanos , Interferon gama/farmacologia , Interleucina-1beta/farmacologia , Intestinos/imunologia , Fator de Necrose Tumoral alfa/farmacologia , Fatores de Virulência/genética
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