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This study aimed to comprehensively assess the influence of the nanotube diameter and the presence of a silicon carbide (SiC) coating on microbial proliferation on nanostructured titanium surfaces. An experiment used 72 anodized titanium sheets with varying nanotube diameters of 50 and 100 nm. These sheets were divided into four groups: non-coated 50 nm titanium nanotubes, SiC-coated 50 nm titanium nanotubes, non-coated 100 nm titanium nanotubes, and SiC-coated 100 nm titanium nanotubes, totaling 36 samples per group. P. gingivalis and T. denticola reference strains were used to evaluate microbial proliferation. Samples were assessed over 3 and 7 days using fluorescence microscopy with a live/dead viability kit and scanning electron microscopy (SEM). At the 3-day time point, fluorescence and SEM images revealed a lower density of microorganisms in the 50 nm samples than in the 100 nm samples. However, there was a consistently low density of T. denticola across all the groups. Fluorescence images indicated that most bacteria were viable at this time. By the 7th day, there was a decrease in the microorganism density, except for T. denticola in the non-coated samples. Additionally, more dead bacteria were detected at this later time point. These findings suggest that the titanium nanotube diameter and the presence of the SiC coating influenced bacterial proliferation. The results hinted at a potential antibacterial effect on the 50 nm diameter and the coated surfaces. These insights contribute valuable knowledge to dental implantology, paving the way for developing innovative strategies to enhance the antimicrobial properties of dental implant materials and mitigate peri-implant infections.
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Titanium implants are subject to bacterial adhesion and peri-implantitis induction, and biosurfactants bring a new alternative to the fight against infections. This work aimed to produce and characterize the biosurfactant from Bacillus subtilis ATCC 19,659, its anti-adhesion and antimicrobial activity, and cell viability. Anti-adhesion studies were carried out against Streptococcus sanguinis, Staphylococcus aureus, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Proteus mirabilis as the minimum inhibitory concentration and the minimum bactericidal concentration. Cell viability was measured against osteoblast and fibroblast cells. The biosurfactant was classified as lipopeptide, with critical micelle concentration at 40 µg mL- 1, and made the titanium surface less hydrophobic. The anti-adhesion effect was observed for Staphylococcus aureus and Streptococcus sanguinis with 54% growth inhibition and presented a minimum inhibitory concentration of 15.7 µg mL- 1 for Streptococcus sanguinis and Aggregatibacter actinomycetemcomitans. The lipopeptide had no cytotoxic effect and demonstrated high potential application against bacterial biofilms.
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Aderência Bacteriana , Biofilmes , Implantes Dentários , Lipopeptídeos , Testes de Sensibilidade Microbiana , Titânio , Titânio/farmacologia , Titânio/química , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Aderência Bacteriana/efeitos dos fármacos , Implantes Dentários/microbiologia , Lipopeptídeos/farmacologia , Humanos , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Bacillus subtilis/efeitos dos fármacos , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/fisiologia , Porphyromonas gingivalis/crescimento & desenvolvimento , Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Propriedades de Superfície , Fibroblastos/efeitos dos fármacos , Fusobacterium nucleatum/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Tensoativos/farmacologiaRESUMO
Dental implant surface properties such as roughness, wettability, and porosity ensure cell interaction and tissue integration. The clinical performance of dental implants depends on the crystallographic texture and protein and cell bonds to the substrates, where grain size, orientation, and inclination are parameters responsible for favoring osteoblast adhesion and limiting bacterial adhesion. The lack of consensus on the best crystallographic plan for cell adhesion prompted this systematic review, which aims to answer the following question: "What is the influence of the crystallographic plane on titanium surfaces on cell adhesion?" by evaluating the literature on the crystallographic characteristics of titanium and how these dictate topographical parameters and influence the cell adhesion of devices made from this material. It followed the Preferred Reporting Standards for Systematic Reviews and Meta-Analyses (PRISMA 2020) registered with the Open Science Framework (OSF) (osf.io/xq6kv). The search strategy was based on the PICOS method. It chose in vitro articles that analyzed crystallographic structure correlated with cell adhesion and investigated the microstructure and its effects on cell culture, different crystal orientation distributions, and the influence of crystallinity. The search strategies were applied to the different electronic databases: PubMed, Scopus, Science Direct, Embase, and Google Scholar, and the articles found were attached to the Rayyan digital platform and assessed blindly. The Joanna Bringgs Institute (JBI) tool assessed the risk of bias. A total of 248 articles were found. After removing duplicates, 192 were analyzed by title and abstract. Of these, 18 were selected for detailed reading in their entirety, 9 of which met the eligibility criteria. The included studies presented a low risk of bias. The role of the crystallographic orientation of the exposed faces in a multicrystalline material is little discussed in the scientific literature and its impact is recognized as dictating the topographical characteristics of the material that facilitate cell adhesion.
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Adesão Celular , Titânio , Titânio/química , Humanos , Propriedades de Superfície , Implantes Dentários , Cristalografia , Animais , Osteoblastos/metabolismo , Osteoblastos/citologiaRESUMO
Candidemia is an opportunistic mycosis with high morbidity and mortality rates. Even though Candida albicans is the main causative agent, other Candida species, such as Candida tropicalis, are relevant etiological agents of candidiasis and candidemia. Compared with C. albicans, there is currently limited information about C. tropicalis' biological aspects, including those related to the cell wall and the interaction with the host. Currently, it is known that its cell wall contains O-linked mannans, and the contribution of these structures to cell fitness has previously been addressed using cells subjected to chemical treatments or in mutants where O-linked mannans and other wall components are affected. Here, we generated a C. tropicalis pmt2∆ null mutant, which was affected in the first step of the O-linked mannosylation pathway. The null mutant was viable, contrasting with C. albicans where this gene is essential. The phenotypical characterization showed that O-linked mannans were required for filamentation; proper cell wall integrity and organization; biofilm formation; protein secretion; and adhesion to extracellular matrix components, in particular to fibronectin; and type I and type II collagen. When interacting with human innate immune cells, it was found that this cell wall structure is dispensable for cytokine production, but mutant cells were more phagocytosed by monocyte-derived macrophages. Furthermore, the null mutant cells showed virulence attenuation in Galleria mellonella larvae. Thus, O-linked mannans are minor components of the cell wall that are involved in different aspects of C. tropicalis' biology.
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Obtener una buena adhesión entre esmalte y bracket es un aspecto fundamental para el éxito del tratamiento en Ortodoncia. Algunos casos presentan desafíos en esta adhesión, especialmente cuando nos enfrentamos ante un esmalte con alteraciones como hipomineralizaciones, hipoplasias o fluorosis dental. Para sobreponer esta dificultad en la unión adhesiva se han propuesto diversas estrategias terapéuticas como es el uso de agentes desproteinizantes. El objetivo de esta revisión narrativa es describir el uso de hipoclorito de sodio como agente desproteinizante en dientes con alteraciones de esmalte para mejorar la adhesión en Ortodoncia. Se realizó una búsqueda bibliográfica en PubMed de los últimos 5 años. Se encontraron 116 artículos, de los cuales 23 cumplieron con los criterios requeridos y fueron seleccionados para la revisión. La desproteinización del esmalte con hipoclorito de sodio como paso previo al grabado ácido, es una estrategia útil en el proceso de cementación de aparatología de ortodoncia fija en dientes con alteraciones del esmalte. El uso de hipoclorito de sodio al 5,25 % es una alternativa de bajo co sto, no invasiva y eficiente para mejorar la fuerza de adhesión en pacientes con alteraciones del esmalte.
Obtaining good adhesion between enamel and bracket is a fundamental aspect for success in Orthodontics. Some cases present challenges in this adhesion, especially when we are faced with enamel with alterations such as hypomineralization, hypoplasia or dental fluorosis. To overcome this difficulty in adhesive bonding, various therapeutic strategies have been proposed, such as the use of deproteinizing agents. The objective of this study is to describe the use of sodium hypochlorite as a deproteinizing agent in teeth with enamel alterations to improve adhesion in Orthodontics. A bibliographic search was carried out in PubMed for articles within the last 5 years. In this study 116 articles were found, of which 23 met the required criteria and were selected for the review. Deproteinization of the enamel with sodium hypochlorite as a prior step to acid etching is an important stage in the cementation process of fixed appliances in orthodontics. The use of 5.25% sodium hypochlorite is a low-cost, non-invasive and efficient alternative to improve adhesion strength in patients with anomalies of tooth enamel.
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La obstrucción intestinal mecánica es un problema quirúrgico significativo en términos de prevalencia, morbimortalidad y costos económicos asociados. En los últimos años se han realizado avances en: detectar mecanismos fisiopatológicos del desarrollo de adherencias, optimizar el diagnóstico de pacientes aptos para manejo conservador, valorar la utilidad intraoperatoria de herramientas que definan la necesidad de resección intestinal y hallar terapias preventivas. El objetivo de esta revisión narrativa es sintetizar la evidencia científica actualizada, publicada referente al diagnóstico y tratamiento de una obstrucción intestinal alta mecánica.
Mechanical small bowel obstruction is a significant surgical problem in terms of prevalence, morbimortality, and associated economic costs. In recent years, advances have been made in: detection of physio pathological mechanisms of adhesion genesis, improvement in diagnosis of patients suitable for conservative treatment, assessment the efficacy of intraoperative tools that define the need for intestinal resection, and development of preventive therapies. The objective of this narrative review is to synthesize the updated scientific evidence published, regarding the diagnosis and treatment of mechanical small bowel obstruction.
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This study aimed to investigating the possible interference caused by glass test tubes on the quantification of bacterial adhesion to hydrocarbons by the MATH test. The adhesion of four bacteria to hexadecane and to glass test tubes was evaluated employing different suspending polar phases. The role of the ionic strength of the polar phase regarding adhesion to glassware was investigated. Within the conditions studied, Gram-positive bacteria adhered to both the test tube and the hydrocarbon regardless of the polar phase employed; meanwhile, Escherichia coli ATCC 25922 did not attach to either one. The capacity of the studied microorganisms to adhere to glassware was associated with their electron-donor properties. The ionic strength of the suspending media altered the patterns of adhesion to glass in a strain-specific manner by defining the magnitude of electrostatic repulsion observed between bacteria and the glass surface. This research demonstrated that glass test tubes may interact with suspended bacterial cells during the MATH test under specific conditions, which may lead to overestimating the percentage of adhesion to hydrocarbons and, thus, to erroneous values of cell surface hydrophobicity.
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Aderência Bacteriana , Vidro , Vidro/química , Escherichia coli , Alcanos/química , Concentração Osmolar , Interações Hidrofóbicas e Hidrofílicas , Hidrocarbonetos/metabolismo , Bactérias Gram-Positivas/isolamento & purificaçãoRESUMO
HYPOTHESIS: The petal effect is a well-known natural phenomenon in surface science and has served as inspiration for the creation of several materials with superhydrophobic qualities and high adhesion. As surface roughness has a crucial role in these properties, being able to modulate it could help us design materials at will. Capillary penetration frustrates diffusion and promotes large contact angles as well as high adhesion. EXPERIMENTS: Polystyrene surfaces were created using the spin-coating technique. By varying the polymer concentration, the surface roughness was modified. To determine the roughness parameters, atomic force microscopy was used. We recorded advancing and receding contact angles using water and glycerol as test liquids to study contact angle hysteresis, the work of adhesion and the apparent surface energy, which was determined with the Chibowski and Perea-Carpio method. For the purpose of elucidating the wetting states, captive bubble experiments were conducted. FINDINGS: Using an easy method, we create polystyrene surfaces with both superhydrophobicity and strong adhesion, where the roughness area factor regulates wetting transitions from Cassie-Baxter to Wenzel. The receding contact angle suggests capillary penetration, which we demonstrate by captive bubble experiments. In addition, a link was found between the surface roughness and apparent surface energy.
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Cow dung (CD) is a material that has been used for millennia by humanity as a stabilizer in earth building techniques in vernacular architecture. However, this stabilization has been little addressed scientifically. In this study, the effect of CD additions was assessed on earth mortars produced with one type of earth from Brazil and two other types from Portugal (from Monsaraz and Caparica). The effect of two volumetric proportions of CD additions were assessed: 10% and 20% of earth + sand. The German standard DIN 18947 was used to perform the physical and mechanical tests, and classify the mortars. In comparison to the reference mortars without CD, the additions reduced linear shrinkage and cracking. An increase in flexural and compressive strengths was not observed only in mortars produced with earth from Monsaraz. In mortars produced with the earth from Caparica, the addition of 10% of CD increased flexural strength by 15% and compressive strength by 34%. For mortars produced with the earth from Brazil, the addition of 10% of CD increased these mechanical strengths by 40%. The increase in adhesive strength and water resistance promoted by the CD additions was observed in mortars produced with all three types of earth. Applied on ceramic brick, the proportion of 10% of CD increased the adherence by 100% for the three types of earth. Applied on adobe, the same proportion of CD also increased it more than 50%. For the water immersion test, the CD additions made possible for the mortar specimens not to disintegrate after a 30 min immersion, with the 20% proportion being more efficient. The effects of the CD on mechanical performance, including adhesion, were more significant on the tropical earth mortars but the effects on water resistance were more significant on the Mediterranean earthen mortars. CD has shown its positive effects and potential for both tropical and Mediterranean earthen plasters and renders tested, justifying being further studied as an eco-efficient bio-stabilizer.
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Here, a polysaccharide derivative acryloyl chitosan (AcCS) is exploited as macro-crosslinker to synthesize a novel ionogel poly (acrylic acid-co-1-Vinyl-3-butyl imidazolium chloride) (AA-IL/AcCS) via a one-pot method. AcCS provides abundant physical and chemical crosslinking sites contributing to the high mechanical stretchability (elongation at break 600 %) and strength (tensile strength 137 kPa) of AA-IL/AcCS. The high-density of dynamic bonds (hydrogen bonds and electrostatic interactions) in the network of ionogels enables self-healing and self-adhesive features of AA-IL/AcCS. Meanwhile, AA-IL/AcCS exhibits high ionic conductivity (0.1 mS/cm) at room temperature and excellent antifreeze ability (-58 °C). The AA-IL/AcCS-based sensor shows diverse sensory capabilities towards temperature and humidity, moreover, it could precisely detect human motions and handwritings signals. Furthermore, AA-IL/AcCS exhibits excellent bactericidal properties against both gram-positive and gram-negative bacteria. This work opens the possibility of polysaccharides as a macro-crosslinkers for preparing ionogel-based sensors for wearable electronics.
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Quitosana , Congelamento , Quitosana/química , Reagentes de Ligações Cruzadas/química , Géis/química , Antibacterianos/química , Antibacterianos/farmacologia , Condutividade Elétrica , Adesivos/química , Humanos , Dispositivos Eletrônicos Vestíveis , Resistência à TraçãoRESUMO
Salmonella Enteritidis, Escherichia coli, and Campylobacter jejuni are among the most common foodborne pathogens worldwide, and poultry products are strongly associated with foodborne pathogen outbreaks. These pathogens are capable of producing biofilms on several surfaces used in the food processing industry, including polyethylene and stainless steel. However, studies on multi-species biofilms are rare. Therefore, this study aimed to develop predictive mathematical models to simulate the adhesion and removal of multispecies biofilms. All combinations of microorganisms resulted in biofilm formation with differences in bacterial counts. E. coli showed the greatest ability to adhere to both surfaces, followed by S. Enteritidis and C. jejuni. The incubation time and temperature did not influence adhesion. Biofilm removal was effective with citric acid and benzalkonium chloride but not with rhamnolipid. Among the generated models, 46 presented a significant coefficient of determination (R2), with the highest R2 being 0.88. These results provide support for the poultry industry in creating biofilm control and eradication programs to avoid the risk of contamination of poultry meat.
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Este trabajo se apoya en los conceptos contrato narcisista primario y secundario para dar cuenta del proceso de filiación y afiliación de la paciente (caso de Agustina) AU
This work relies on the concepts of primary and secondary Narcissistic Contract to understand the process of affiliation and filiation of the patient (Agustina Ìs case) AU
Ce travail s'appuie sur les concepts de contrat narcissique primaire et secondaire pour rendre compte du processus de filiation et du processus d Ìadhésiondu patient (cas d ÌAgustina) AU
Este trabalho baseia-se nos conceitos de contrato narcísico primário e secundário para dar conta do processo de filiação e afiliaçãodo paciente (caso de Agustina) AU
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Humanos , Feminino , Adolescente , Família/psicologia , Identificação Psicológica , Psicoterapia Interpessoal/métodosRESUMO
Introduction: Post-processing (PP) is performed to improve the surface, which can favor microbial adhesion and consequent pathological manifestations that impair the indication of polylactic acid (PLA) obtained by fused filament fabrication (FFF) for biomedical applications. This aims to evaluate the influence of chemical, thermal, and mechanical PP on the adhesion of Streptococcus mutants and Candida albicans, roughness, and wettability of the PLA obtained by FFF with and without thermal aging. Methods: The specimens were designed in the 3D modeling program and printed. The chemical PP was performed by immersion in chloroform, the thermal by the annealing method, and the mechanical by polishing. Thermal aging was performed by alternating the temperature from 5 °C to 55 °C with 5000 cycles. Colony-forming unit (CFU/mL) counting was performed on dual-species biofilm of C. albicans and S. mutans. Roughness was analyzed by rugosimeter and wettability by the sessile drop technique. Data were verified for normality using the Shapiro-Wilk test, two-way ANOVA (α = 0.05) applied for CFU and wettability, and Kruskal-Wallis (α = 0.05) for roughness. Results: Chemical, thermal, and mechanical PP methods showed no influence on CFU/mL of C. albicans (p = 0.296) and S. mutans (p = 0.055). Thermal aging did not influence microbial adhesion. Chemical PP had lower roughness, which had increased after aging. Wettability of the mechanical PP was lower. Conclusions: Post-processing techniques, do not present an influence on the adhesion of S. mutans and C. albicans in PLA obtained by FFF, chemical PP reduced roughness, and mechanical reduced wettability. Thermal aging did not alter the microbial adhesion and altered the roughness and wettability.
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Human amoebiasis still represents a major health problem worldwide. Metronidazole has been used as the most common drug to treat the disease; however, it is also known that the drug causes undesirable side effects. This has led to the search for new pharmacological alternatives which include phytochemical compounds with antiamoebic effects. We analyzed the amoebicidal activity of stevioside (STV), a diterpene glycoside present in Stevia rebaudiana, on trophozoites of E. histolytica. Different concentrations of STV were tested, and an inhibitory concentration of 50% of cell viability (IC50) was determined with an exposition of 9.53 mM for 24 h. Trophozoites exposed to STV showed morphological changes evidenced by the decrease in the basic structures related to the movement and adherence to the substrate, as well as ultrastructural features characterized by a loss of regularity on the cell membrane, an increase in cytoplasmic granularity, and an increase in apparent autophagic vacuoles. Also, the decrease in cysteine protease expression and the proteolytic activity of trophozoites to degrade the cell monolayer were analyzed. A histological analysis of hamster livers inoculated with trophozoites and treated with STV showed changes related to the granulomatous reaction of the liver parenchymal tissue. Our results constitute the first report related to the possible use of STV as a therapeutic alternative in amoebiasis.
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BACKGROUND: Endometrial fibrosis, a significant characteristic of intrauterine adhesion (IUA), is caused by the excessive differentiation and activation of endometrial stromal cells (ESCs). Glutaminolysis is the metabolic process of glutamine (Gln), which has been implicated in multiple types of organ fibrosis. So far, little is known about whether glutaminolysis plays a role in endometrial fibrosis. METHODS: The activation model of ESCs was constructed by TGF-ß1, followed by RNA-sequencing analysis. Changes in glutaminase1 (GLS1) expression at RNA and protein levels in activated ESCs were verified experimentally. Human IUA samples were collected to verify GLS1 expression in endometrial fibrosis. GLS1 inhibitor and glutamine deprivation were applied to ESCs models to investigate the biological functions and mechanisms of glutaminolysis in ESCs activation. The IUA mice model was established to explore the effect of glutaminolysis inhibition on endometrial fibrosis. RESULTS: We found that GLS1 expression was significantly increased in activated ESCs models and fibrotic endometrium. Glutaminolysis inhibition by GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl) ethyl sulfide (BPTES or glutamine deprivation treatment suppressed the expression of two fibrotic markers, α-SMA and collagen I, as well as the mitochondrial function and mTORC1 signaling in ESCs. Furthermore, inhibition of the mTORC1 signaling pathway by rapamycin suppressed ESCs activation. In IUA mice models, BPTES treatment significantly ameliorated endometrial fibrosis and improved pregnancy outcomes. CONCLUSION: Glutaminolysis and glutaminolysis-associated mTOR signaling play a role in the activation of ESCs and the pathogenesis of endometrial fibrosis through regulating mitochondrial function. Glutaminolysis inhibition suppresses the activation of ESCs, which might be a novel therapeutic strategy for IUA.
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Glutamina , Mitocôndrias , Feminino , Camundongos , Humanos , Animais , Glutamina/metabolismo , Fibrose , Mitocôndrias/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , RNA/metabolismo , Endométrio/metabolismo , Endométrio/patologiaRESUMO
In several cancer types, metastasis is associated with poor prognosis, survival, and quality of life, representing a life risk more significant than the primary tumor itself. Metastasis is a multi-step process that spreads tumor cells from primary sites to surrounding or distant organs, originating secondary tumors. The interconnected steps that drive metastasis depend of several capabilities that enable cells to detach from the primary tumor, acquire motility and migrate through the basal membrane; invade and spread through the vascular system, and finally settle and originate a new tumor. Recently, stress-induced phosphoprotein 1 (STIP1) has emerged as a protein capable of driving tumor cells through these metastasis steps by mediating several biological processes and signaling pathways. This protein is mainly known for its function as a co-chaperone, acting as a scaffold for the interaction of its client heat-shock proteins Hsp70/90 chaperones; however, it is also known that STIP1 can act independently of chaperones to activate downstream phosphorylation pathways. The over-expression of STIP1 has been reported across various cancer types, identifying it as a potential biomarker for predicting patient prognosis and monitoring the progression of metastasis. Here, we present a discussion on how this co-chaperone mediates the initial steps of metastasis (cell adhesion loss, epithelial-to-mesenchymal transition, and angiogenesis), highlighting the biological mechanisms in which STIP1 plays a vital role, also presenting an overview of the current knowledge regarding its clinical relevance.
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Proteínas de Choque Térmico , Metástase Neoplásica , Neoplasias , Humanos , Neoplasias/patologia , Neoplasias/metabolismo , Proteínas de Choque Térmico/metabolismo , Transdução de Sinais , Animais , Chaperonas Moleculares/metabolismo , Transição Epitelial-MesenquimalRESUMO
Trichosporon spp. is an emerging opportunistic pathogen and a common cause of both superficial and invasive infections. Although Trichosporon asahii is the most frequently isolated species, Trichosporon cutaneum is also widely observed, as it is the predominant agent in cases of white Piedra and onychomycosis. Trichosporon spp. is a known to produce biofilms, which serve as one of its virulence mechanisms, however, there is limited data available on biofilms formed by T. cutaneum. Thus, the aim of this study was to assess the adhesion and biofilm formation of two clinical isolates of T. cutaneum under various environmental conditions (including temperature, nutrient availability, and carbon source), as well as their tolerance to fluconazole. Adhesion was tested on common abiotic substrates (such as silicone, glass, and stainless steel), revealing that T. cutaneum readily adhered to all surfaces tested. CV staining was applied for the evaluation of the environment influence on biofilm efficiency and it was proved that the nutrient availability has a major impact. Additionaly, fluorescent staining was employed to visualize the morphology of T. cutaneum biofilm and its survival in the presence of fluconazole. Hyphae production was shown to play a role in elevated biofilm production in minimal medium and increased tolerance to fluconazole.
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Biofilmes , Trichosporon , Biofilmes/crescimento & desenvolvimento , Trichosporon/fisiologia , Trichosporon/isolamento & purificação , Trichosporon/efeitos dos fármacos , Humanos , Tricosporonose/microbiologia , Antifúngicos/farmacologia , Fluconazol/farmacologiaRESUMO
The increase of bacterial resistance to antibiotics is a growing concern worldwide and the search for new therapies could cost billions of dollars and countless lives. Inert surfaces are major sources of contamination due to easier adhesion and formation of bacterial biofilms, hindering the disinfection process. Therefore, the objective of this study was to develop a photoactivatable and anti-adhesive kappa-carrageenan coating using proanthocyanidin as a photosensitizer. The complete reduction (>5-log10 CFU/cm3) of culturable cells of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa pathogens was achieved after 30 min of exposure to visible light (420 nm; 30 mW/cm2) with 5 % (w/v) of the photosensitizer. Cell membrane damage was confirmed by measuring potassium leakage, epifluorescence microscopy and bacterial motility analysis. Overall, visible light irradiation on coated solid surfaces mediated by proanthocyanidin showed no cytotoxicity and inactivated clinically important pathogens through the generation of reactive oxygen species, inhibiting bacterial initial adhesion. The developed coating is a promising alternative for a wide range of applications related to surface disinfection and food biopreservation.
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Fármacos Fotossensibilizantes , Proantocianidinas , Carragenina/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Proantocianidinas/farmacologia , Luz , Biofilmes , Escherichia coli , BactériasRESUMO
Glioblastoma (GBM) is one of the most common types of brain tumor in adults. Despite the availability of treatments for this disease, GBM remains one of the most lethal and difficult types of tumors to treat, and thus, a majority of patients die within 2 years of diagnosis. Infection with Zika virus (ZIKV) inhibits cell proliferation and induces apoptosis, particularly in developing neuronal cells, and thus could potentially be considered an alternative for GBM treatment. In the present study, two GBM cell lines (U-138 and U-251) were infected with ZIKV at different multiplicities of infection (0.1, 0.01 and 0.001), and cell viability, migration, adhesion, induction of apoptosis, interleukin levels and CD14/CD73 cell surface marker expression were analyzed. The present study demonstrated that ZIKV infection promoted loss of cell viability and increased apoptosis in U-138 cells, as measured by MTT and triplex assay, respectively. Changes in cell migration, as determined by wound healing assay, were not observed; however, the GBM cell lines exhibited an increase in cell adhesion when compared with non-tumoral cells (Vero). The Luminex immunoassay showed a significant increase in the expression levels of IL-4 specifically in U-251 cells (MOI 0.001) following exposure to ZIKV. There was no significant change in the expression levels of IFN-γ upon ZIKV infection in the cell lines tested. Furthermore, a marked increase in the percentage of cells expressing the CD14 surface marker was observed in both GBM cell lines compared with in Vero cells; and significantly increased CD73 expression was observed particularly in U-251 cells, when compared with uninfected cells. These findings indicate that ZIKV infection could lead to reduced cell viability, elevated CD73 expression, improved cellular adherence, and higher rates of apoptosis in glioblastoma cells. Further studies are required to explore the potential use of ZIKV in the treatment of GBM.