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1.
Mol Divers ; 26(6): 3399-3409, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35143033

RESUMO

The rise of antimicrobial-resistant phenotypes and the spread of the global pandemic of COVID-19 are worsening the outcomes of hospitalized patients for invasive fungal infections. Among them, candidiases are seriously worrying, especially since the currently available drug armamentarium is extremely limited. We recently reported a new class of macrocyclic amidinoureas bearing a guanidino tail as promising antifungal agents. Herein, we present the design and synthesis of a focused library of seven derivatives of macrocyclic amidinoureas, bearing a second phenyl ring fused with the core. Biological activity evaluation shows an interesting antifungal profile for some compounds, resulting to be active on a large panel of Candida spp. and C. neoformans. PAMPA experiments for representative compounds of the series revealed a low passive diffusion, suggesting a membrane-based mechanism of action or the involvement of active transport systems. Also, compounds were found not toxic at high concentrations, as assessed through MTT assays.


Assuntos
COVID-19 , Cryptococcus neoformans , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Candida
2.
Mycoses ; 65(12): 1127-1136, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35842900

RESUMO

BACKGROUND: Onychomycosis (OM) accounts for about 50% of nail disorders in industrialised countries. Essential oils (EOs), aromatic natural compounds, are known for their antimicrobial activity. OBJECTIVE: The aim of this work was to evaluate the antifungal efficacy of seven EOs and a commercial MIX against 10 dermatophytes responsible for OM to select the most effective ones to be included in a preventive or curative formulation based on a green natural nail polish (GNNP). METHODS: Micro-broth dilution tests in line with EUCAST guidelines and olfactory satisfaction test were performed to select the best natural compounds previously analysed by SPME coupled with GC-MS. The same method was used to evaluate the release over time of the active compounds present in the two modified-GNNPs made by adding the best natural compound selected (the C. citratus EO) and the MIX. Furthermore, to evaluate the preventive and curative activity of modified-GNNPs, ex vivo experiments on healthy or colonised nails were performed. RESULTS AND CONCLUSIONS: Data showed that MIX-modified-GNNP had preventive activity as it inhibits the fungal growth by releasing its active ingredients for 7 days, while the OE-modified GNNP acts as a natural drug showing cytocidal activity on nails colonised by dermatophytes, but it requires two weekly applications.


Assuntos
Óleos Voláteis , Onicomicose , Humanos , Onicomicose/tratamento farmacológico , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Polônia , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Unhas
3.
Odontology ; 110(4): 710-718, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35355145

RESUMO

Membrane exposure is a widely reported and relatively common complication in Guided Bone Regeneration (GBR) procedures. The introduction of micro-porous dPTFE barriers, which are impervious to bacterial cells, could reduce the technique sensitivity to membrane exposure, even if there are no studies investigating the potential passage of bacterial metabolites through the barrier. Aim of this study was the in vitro evaluation of the permeability of three different GBR membranes (dPTFE, native and cross-linked collagen membranes) to Porphyromonas gingivalis; in those cases, where bacterial penetration could not be observed, another purpose was the analysis of the viability and differentiation capability of an osteosarcoma (U2OS) cell line in presence of bacteria eluate obtained through membrane percolation. A system leading to the percolation of P. gingivalis broth culture through the experimental membranes was arranged to assess the permeability to bacteria after 24 and 72 h of incubation. The obtained solution was then added to U2OS cell cultures which underwent, after 10 days of incubation, MTT and red alizarin essays. The dPTFE membrane showed resistance to bacterial penetration, while both types of collagen membranes were crossed by P. gingivalis after 24 h. The bacteria eluate filtered through dPTFE membrane didn't show any toxicity on U2OS cells. Results of this study demonstrate that dPTFE membranes can contrast the penetration of both P. gingivalis and its metabolites toxic for osteoblast-like cells. The toxicity analysis was not possible for the collagen membranes, since permeability to bacterial cells was observed within the first period of incubation.


Assuntos
Colágeno , Membranas Artificiais , Regeneração Óssea , Osteoblastos/metabolismo , Permeabilidade , Porphyromonas gingivalis
4.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35216297

RESUMO

The increasing resistance of fungi to antibiotics is a severe challenge in public health, and newly effective drugs are required. Promising potential medications are lipopeptides, linear antimicrobial peptides (AMPs) conjugated to a lipid tail, usually at the N-terminus. In this paper, we investigated the in vitro and in vivo antifungal activity of three short myristoylated and non-myristoylated peptides derived from a mutant of the AMP Chionodracine. We determined their interaction with anionic and zwitterionic membrane-mimicking vesicles and their structure during this interaction. We then investigated their cytotoxic and hemolytic activity against mammalian cells. Lipidated peptides showed a broad spectrum of activity against a relevant panel of pathogen fungi belonging to Candida spp., including the multidrug-resistant C. auris. The antifungal activity was also observed vs. biofilms of C. albicans, C. tropicalis, and C. auris. Finally, a pilot efficacy study was conducted on the in vivo model consisting of Galleria mellonella larvae. Treatment with the most-promising myristoylated peptide was effective in counteracting the infection from C. auris and C. albicans and the death of the larvae. Therefore, this myristoylated peptide is a potential candidate to develop antifungal agents against human fungal pathogens.


Assuntos
Antifúngicos , Candida , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Biofilmes , Candida albicans , Humanos , Larva , Lipopeptídeos/farmacologia , Mamíferos , Testes de Sensibilidade Microbiana
5.
Microb Ecol ; 82(1): 215-223, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33471174

RESUMO

Here, we investigated the possible linkages among geophagy, soil characteristics, and gut mycobiome of indri (Indri indri), an endangered lemur species able to survive only in wild conditions. The soil eaten by indri resulted in enriched secondary oxide-hydroxides and clays, together with a high concentration of specific essential micronutrients. This could partially explain the role of the soil in detoxification and as a nutrient supply. Besides, we found that soil subject to geophagy and indris' faeces shared about 8.9% of the fungal OTUs. Also, several genera (e.g. Fusarium, Aspergillus and Penicillium) commonly associated with soil and plant material were found in both geophagic soil and indri samples. On the contrary, some taxa with pathogenic potentials, such as Cryptococcus, were only found in indri samples. Further, many saprotrophs and plant-associated fungal taxa were detected in the indri faeces. These fungal species may be involved in the digestion processes of leaves and could have a beneficial role in their health. In conclusion, we found an intimate connection between gut mycobiome and soil, highlighting, once again, the potential consequent impacts on the wider habitat.


Assuntos
Indriidae , Lemur , Micobioma , Animais , Ecossistema , Pica , Microbiologia do Solo
6.
Phytother Res ; 35(5): 2477-2486, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33300141

RESUMO

The aim of this systematic review is to collect clinical trials conducted using essential oils (EOs) in obstetric symptoms by evaluating if and in which context the aromatherapy practice is effective in obstetrics. The research was conducted by using the databases of EMBASE, Medline, Biosis and Toxcenter, PubMed, and Google Scholar search engine, selecting articles from January 2004 to July 2020. This study was performed according to the MOOSE and PRISMA guidelines. Only the randomized clinical trials were considered, and in cases of multiple publications, it was considered the most up to date information. Biases were highlighted. In the presence of homogeneous data, pooling statistics and meta-analysis were applied. The research led to 71 articles, 17 of which were eligible. Among the trials selected, eight investigated the effectiveness of EOs on anxiety, depression, and stress. Two concerned the treatment of nausea and vomiting, six evaluated the application of EOs on labor for pain treatment, and two showed the effectiveness in the treatment of episiotomy. The heterogeneity of works carried out so far has made it possible to develop a meta-analysis only in the field of pain treatment during childbirth, identifying the effectiveness of the EOs Lavandula spp. and Rosa damascena.

7.
Adv Exp Med Biol ; 1282: 21-35, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468360

RESUMO

The clinical challenge on surface engineering of medical devices to prevent microorganisms adhesion and biofilm formation, has become an essential aspect for medical implants. Antibacterial properties of Graphene Oxide (GO) have been demonstrated across a broad spectrum of bacteria, and the different mechanisms of action with which this nanomaterial interacts with the microbial surface have been elucidated in detail. Innovative protective coatings based on graphene film and hydrogel could represent an innovative solution for the prevention of nosocomial pathogens colonization on implantable device. This brief review mainly focuses on the applications of graphene in nanomedicine with a particular deepening on the antibacterial properties of GO and GO-based nanomaterials. In order to evaluate the possible future applications of GO as an anti-biofilm coating material for medical devices, studies on the ability of graphene coated surface to prevent microbial adhesion are also discussed. A concise review on in vitro toxicity and in vivo safety is also presented.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Equipamentos e Provisões/microbiologia , Grafite/farmacologia , Humanos
8.
Proc Natl Acad Sci U S A ; 113(19): 5388-93, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27118832

RESUMO

Targeting a host factor essential for the replication of different viruses but not for the cells offers a higher genetic barrier to the development of resistance, may simplify therapy regimens for coinfections, and facilitates management of emerging viral diseases. DEAD-box polypeptide 3 (DDX3) is a human host factor required for the replication of several DNA and RNA viruses, including some of the most challenging human pathogens currently circulating, such as HIV-1, Hepatitis C virus, Dengue virus, and West Nile virus. Herein, we showed for the first time, to our knowledge, that the inhibition of DDX3 by a small molecule could be successfully exploited for the development of a broad spectrum antiviral agent. In addition to the multiple antiviral activities, hit compound 16d retained full activity against drug-resistant HIV-1 strains in the absence of cellular toxicity. Pharmacokinetics and toxicity studies in rats confirmed a good safety profile and bioavailability of 16d. Thus, DDX3 is here validated as a valuable therapeutic target.


Assuntos
Antivirais/administração & dosagem , RNA Helicases DEAD-box/antagonistas & inibidores , RNA Helicases DEAD-box/metabolismo , Terapia de Alvo Molecular/métodos , Replicação Viral/efeitos dos fármacos , Replicação Viral/fisiologia , Desenho de Fármacos , Inibidores Enzimáticos
9.
Helicobacter ; 22(2)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27484400

RESUMO

BACKGROUND: Preeclampsia (PE) is a major cause of maternal and neonatal morbidity and mortality. Epidemiological association between Helicobacter pylori (Hp) infection and PE onset has been widely shown. The aim of this study was to analyze a possible correlation between Hp infection and the severity of clinical presentation of PE and to identify an immunologic mechanism triggered by Hp infection potentially contributing to the pathogenesis of PE. MATERIALS AND METHODS: Sera from 93 preeclamptic women and 87 healthy pregnant women were tested for Hp infection by immunoassay and for anti-CagA antibodies by Western blot assay. The serologic results were correlated with the clinical features of PE. The functional effect of serum IgG fractions, positive or negative for Hp, from preeclamptic women or controls were tested on trophoblast and endothelial cell cultures and in a murine model of angiogenesis. RESULTS: Preeclamptic women showed higher seroprevalence of Hp infection (57.0%) compared to controls (33.3%) (P<.001). The seropositivity for CagA-positive strains of Hp was 45.2% in preeclamptic women vs 13.7% in controls (P<.001). In PE women, Hp infection was associated with abnormality of uterine arteries Doppler (P<.001). Hp+ IgG fractions from preeclamptic women bound to trophoblast and endometrial endothelial cell cultures, reducing in vitro invasiveness and angiogenesis, respectively, and inhibited angiogenesis in mice. CONCLUSIONS: Our data show, for the first time, an association between Hp infection and PE with abnormal uterine arteries Doppler velocimetry, suggesting a role for Hp infection in impairing placental development and increasing the risk to develop PE. This study opens the new perspective of a potential screening and treatment for Hp infection in pregnancy.


Assuntos
Infecções por Helicobacter/complicações , Placenta/patologia , Pré-Eclâmpsia/patologia , Adulto , Animais , Anticorpos Antibacterianos/sangue , Western Blotting , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Feminino , Humanos , Camundongos Nus , Neovascularização Fisiológica/efeitos dos fármacos , Gravidez , Trofoblastos/efeitos dos fármacos , Trofoblastos/fisiologia , Ultrassonografia Doppler , Artéria Uterina/diagnóstico por imagem , Artéria Uterina/patologia , Adulto Jovem
10.
Appl Environ Microbiol ; 82(22): 6633-6644, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590821

RESUMO

Besides being part of anti-Helicobacter pylori treatment regimens, proton pump inhibitors (PPIs) are increasingly being used to treat dyspepsia. However, little is known about the effects of PPIs on the human gastric microbiota, especially those related to H. pylori infection. The goal of this study was to characterize the stomach microbial communities in patients with dyspepsia and to investigate their relationships with PPI use and H. pylori status. Using 16S rRNA gene pyrosequencing, we analyzed the mucosa-associated microbial populations of 24 patients, of whom 12 were treated with the PPI omeprazole and 9 (5 treated and 4 untreated) were positive for H. pylori infection. The Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria phyla accounted for 98% of all of the sequences, with Helicobacter, Streptococcus, and Prevotella ranking among the 10 most abundant genera. H. pylori infection or PPI treatment did not significantly influence gastric microbial species composition in dyspeptic patients. Principal-coordinate analysis of weighted UniFrac distances in these communities revealed clear but significant separation according to H. pylori status only. However, in PPI-treated patients, Firmicutes, particularly Streptococcaceae, were significantly increased in relative abundance compared to those in untreated patients. Consistently, Streptococcus was also found to significantly increase in relation to PPI treatment, and this increase seemed to occur independently of H. pylori infection. Our results suggest that Streptococcus may be a key indicator of PPI-induced gastric microbial composition changes in dyspeptic patients. Whether the gastric microbiota alteration contributes to dyspepsia needs further investigation. IMPORTANCE: Although PPIs have become a popular treatment choice, a growing number of dyspeptic patients may be treated unnecessarily. We found that patients treated with omeprazole showed gastric microbial communities that were different from those of untreated patients. These differences regarded the abundances of specific taxa. By understanding the relationships between PPIs and members of the gastric microbiota, it will be possible to envisage new strategies for better managing patients with dyspepsia.


Assuntos
Bactérias/isolamento & purificação , Dispepsia/microbiologia , Mucosa Gástrica/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Infecções por Helicobacter/microbiologia , Inibidores da Bomba de Prótons/uso terapêutico , Adulto , Idoso , Antibacterianos/uso terapêutico , Bactérias/classificação , Bactérias/genética , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Dispepsia/tratamento farmacológico , Feminino , Firmicutes/classificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Mucosa Gástrica/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Genes de RNAr , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Omeprazol/uso terapêutico , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Inibidores da Bomba de Prótons/efeitos adversos , RNA Ribossômico 16S/genética , Streptococcus/classificação , Streptococcus/genética , Streptococcus/isolamento & purificação
11.
Blood Purif ; 42(4): 294-300, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27577953

RESUMO

BACKGROUND: This study aims to evaluate, in patients on chronic hemodialysis (PHD), the levels of endotoxin through a chemiluminescent bioassay based on the oxidative burst reaction of activated neutrophils to complement coated LPS-IgM immune complexes and define the variables possibly correlated. METHODS: In 61 PHD, we measured serum endotoxin activity (EA) with the Endotoxin Activity Assay (EAA™) and we defined the possible association with demographic, clinical and laboratory variables. RESULTS: Mean serum EA was 0.43 ± 0.26 UI. EA was low (<0.40) in 29 patients (47.5%), intermediate (0.40-0.60) in 14 (23%) and high (>0.60) in 18 (29.5%). A significant exponential relationship was detected between EA and serum interleukin-6 (IL-6) levels (r = 0.871). At the multiple regression analysis, intermediate-high EA was directly associated only with serum IL-6 levels. In a second model of multiple regression analysis without the variable serum IL-6 levels, intermediate-high EA was directly associated with constipation and serum troponin levels and inversely associated with serum albumin and the monthly number of sevelamer tablets. CONCLUSIONS: A high percentage of PHD has intermediate or high EA. Intermediate-high EA is significantly associated with serum IL-6 levels.


Assuntos
Interleucina-6/sangue , Diálise Renal , Endotoxinas/sangue , Humanos , Análise Multivariada , Albumina Sérica
12.
Infect Immun ; 83(1): 364-71, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385793

RESUMO

We previously showed that the mutant strain of Enterococcus faecalis lacking the transcriptional regulator SlyA is more virulent than the parental strain. We hypothesized that this phenotype was due to overexpression of the second gene of the slyA operon, ef_3001, renamed pmvE (for polyamine metabolism and virulence of E. faecalis). PmvE shares strong homologies with N(1)-spermidine/spermine acetyltransferase enzymes involved in the metabolism of polyamines. In this study, we used an E. faecalis strain carrying the recombinant plasmid pMSP3535-pmvE (V19/p3535-pmvE), which allows the induction of pmvE by addition of nisin. Thereby, we showed that the overexpression of PmvE increased the virulence of E. faecalis in the Galleria mellonella infection model, as well as the persistence within peritoneal macrophages. We were also able to show a direct interaction between the His-tagged recombinant PmvE (rPmvE) protein and putrescine by the surface plasmon resonance (SPR) technique on a Biacore instrument. Moreover, biochemical assays showed that PmvE possesses an N-acetyltransferase activity toward polyamine substrates. Our results suggest that PmvE contributes to the virulence of E. faecalis, likely through its involvement in the polyamine metabolism.


Assuntos
Acetiltransferases/metabolismo , Enterococcus faecalis/crescimento & desenvolvimento , Acetiltransferases/genética , Animais , Expressão Gênica , Lepidópteros , Ligação Proteica , Putrescina/metabolismo , Ressonância de Plasmônio de Superfície , Virulência
13.
BMC Microbiol ; 15: 112, 2015 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-26003173

RESUMO

BACKGROUND: Mechanisms underlying the transition from commensalism to virulence in Enterococcus faecalis are not fully understood. We previously identified the enterococcal leucine-rich protein A (ElrA) as a virulence factor of E. faecalis. The elrA gene is part of an operon that comprises four other ORFs encoding putative surface proteins of unknown function. RESULTS: In this work, we compared the susceptibility to phagocytosis of three E. faecalis strains, including a wild-type (WT), a ΔelrA strain, and a strain overexpressing the whole elr operon in order to understand the role of this operon in E. faecalis virulence. While both WT and ΔelrA strains were efficiently phagocytized by RAW 264.7 mouse macrophages, the elr operon-overexpressing strain showed a decreased capability to be internalized by the phagocytic cells. Consistently, the strain overexpressing elr operon was less adherent to macrophages than the WT strain, suggesting that overexpression of the elr operon could confer E. faecalis with additional anti-adhesion properties. In addition, increased virulence of the elr operon-overexpressing strain was shown in a mouse peritonitis model. CONCLUSIONS: Altogether, our results indicate that overexpression of the elr operon facilitates the E. faecalis escape from host immune defenses.


Assuntos
Proteínas de Bactérias/genética , Enterococcus faecalis/fisiologia , Óperon , Peritonite/microbiologia , Fagocitose , Animais , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Enterococcus faecalis/genética , Enterococcus faecalis/patogenicidade , Regulação Bacteriana da Expressão Gênica , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Macrófagos/metabolismo , Camundongos , Virulência
14.
Eur Endod J ; 9(1): 81-88, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37965676

RESUMO

OBJECTIVE: The aim of this in vitro study was to compare the smear layer and debris removal and antimicrobial activity of two dual-action irrigating solutions for continuous chelation (Triton; Brasseler, Savannah, USA and Dual Rinse HEDP; Medcem GmbH, Weinfelden, Switzerland) with a dual step irrigation protocol with sodium hypochlorite (NaOCl) followed by ethylenediaminetetraacetic acid (EDTA). METHODS: Thirty single-rooted single-canal teeth were divided into three groups (n=10) and irrigated with Triton, Dual Rinse HEDP mixed with 6% NaOCl and 6% NaOCl/17% EDTA. The teeth were observed under a scanning electron microscope (SEM) to assess the canal wall cleanliness. In addition, 80 dentine discs were contaminated with Candida albicans and 80 discs with Enterococcus faecalis and irrigated with Triton, Dual Rinse HEDP mixed with 6% NaOCl and 6% NaOCl/17% EDTA or not treated (n=20). Fifteen discs were used to evaluate colony-forming units, while 5 discs were analysed by SEM. Data were analysed using the Shapiro- Wilk, Kruskal-Wallis and One-Way ANOVA tests. RESULTS: Triton was statistically more effective than Dual Rinse HEDP and NaOCl/EDTA in removing debris (p<0.05), except with NaOCl/EDTA in the coronal third. Triton was more effective than Dual Rinse HEDP in removing the smear layer from the apical and middle thirds (p<0.05). All the irrigation protocols significantly re- duced the number of E. faecalis. The Triton group showed the lowest number of remaining C. albicans (p<0.05). CONCLUSION: Triton was the most effective irrigation solution in removing debris and as effective as NaOCl/ EDTA in removing the smear layer. Triton showed the highest efficacy against C. albicans. New irrigating solutions that provide continuous chelation may provide an alternative to current irrigation protocols.


Assuntos
Anti-Infecciosos , Camada de Esfregaço , Humanos , Ácido Edético/farmacologia , Ácido Etidrônico , Microscopia Eletrônica de Varredura , Cavidade Pulpar , Preparo de Canal Radicular/métodos , Irrigantes do Canal Radicular/farmacologia , Quelantes/farmacologia , Anti-Infecciosos/farmacologia
15.
Plants (Basel) ; 13(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38611496

RESUMO

BACKGROUND: The 2015 Nobel Prize in Medicine, awarded for the discovery of artemisinin in Artemisia annua, reignited interest in aromatic plants, including Artemisia absinthium L. This article delves into the historical, ethnopharmacological and medicinal significance of A. absinthium, examining its bitter taste noted since ancient Greek times and its association with medicinal properties throughout history. Despite being banned in the 20th century due to perceived health risks; recent research has led to the reconsideration of A. absinthium's potential applications. This study focuses on the prebiotic efficacy of essential oils (EOs) from two Artemisia species: A. absinthium and A. annua. MATERIALS AND METHODS: A broth microdilution test, growth curve test and in vivo models were used to study the impact of low doses (from 0.5% v/v to 0.00048 v/v) of Artemisia spp-EO on the three probiotic strains (Lactobacillus, Lactobacillus casei and Saccharomyces boulardii). RESULTS: These essential oils, when used in minimal concentrations (lower than 0.06% v/v), are safe and exhibit prebiotic effects on major probiotic strains, supporting the traditional culinary use of Artemisia spp. CONCLUSION: This research opens avenues for potential applications in the food industry, emphasizing the need for further exploration into the prebiotic properties of Artemisia spp-EOs and their influence on the microbiota.

16.
Sci Rep ; 14(1): 3344, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336904

RESUMO

Endoscopic Retrograde Cholangio-Pancreatography (ERCP) with biliary stenting is a minimally invasive medical procedure employed to address both malignant and benign obstructions within the biliary tract. Benign biliary strictures (BBSs), typically arising from surgical interventions such as liver transplants and cholecystectomy, as well as chronic inflammatory conditions, present a common clinical challenge. The current gold standard for treating BBSs involves the periodic insertion of plastic stents at intervals of 3-4 months, spanning a course of approximately one year. Unfortunately, stent occlusion emerges as a prevalent issue within this treatment paradigm, leading to the recurrence of symptoms and necessitating repeated ERCPs. In response to this clinical concern, we initiated a pilot study, delving into the microbial composition present in bile and on the inner surfaces of plastic stents. This investigation encompassed 22 patients afflicted by BBSs who had previously undergone ERCP with plastic stent placement. Our preliminary findings offered promising insights into the microbial culprits behind stent occlusion, with Enterobacter and Lactobacillus spp. standing out as prominent bacterial species known for their biofilm-forming tendencies on stent surfaces. These revelations hold promise for potential interventions, including targeted antimicrobial therapies aimed at curtailing bacterial growth on stents and the development of advanced stent materials boasting anti-biofilm properties.


Assuntos
Sistema Biliar , Colestase , Humanos , Bile , Projetos Piloto , Resultado do Tratamento , Colestase/cirurgia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Stents , Estudos Retrospectivos
17.
Antimicrob Agents Chemother ; 57(3): 1275-82, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23263007

RESUMO

Aspergillus fumigatus biofilms represent a problematic clinical entity, especially because of their recalcitrance to antifungal drugs, which poses a number of therapeutic implications for invasive aspergillosis, the most difficult-to-treat Aspergillus-related disease. While the antibiofilm activities of amphotericin B (AMB) deoxycholate and its lipid formulations (e.g., liposomal AMB [LAMB]) are well documented, the effectiveness of these drugs in combination with nonantifungal agents is poorly understood. In the present study, in vitro interactions between polyene antifungals (AMB and LAMB) and alginate lyase (AlgL), an enzyme degrading the polysaccharides produced as extracellular polymeric substances (EPSs) within the biofilm matrix, against A. fumigatus biofilms were evaluated by using the checkerboard microdilution and the time-kill assays. Furthermore, atomic force microscopy (AFM) was used to image and quantify the effects of AlgL-antifungal combinations on biofilm-growing hyphal cells. On the basis of fractional inhibitory concentration index values, synergy was found between both AMB formulations and AlgL, and this finding was also confirmed by the time-kill test. Finally, AFM analysis showed that when A. fumigatus biofilms were treated with AlgL or polyene alone, as well as with their combination, both a reduction of hyphal thicknesses and an increase of adhesive forces were observed compared to the findings for untreated controls, probably owing to the different action by the enzyme or the antifungal compounds. Interestingly, marked physical changes were noticed in A. fumigatus biofilms exposed to the AlgL-antifungal combinations compared with the physical characteristics detected after exposure to the antifungals alone, indicating that AlgL may enhance the antibiofilm activity of both AMB and LAMB, perhaps by disrupting the hypha-embedding EPSs and thus facilitating the drugs to reach biofilm cells. Taken together, our results suggest that a combination of AlgL and a polyene antifungal may prove to be a new therapeutic strategy for invasive aspergillosis, while reinforcing the EPS as a valuable antibiofilm drug target.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Proteínas de Bactérias/farmacologia , Biofilmes/efeitos dos fármacos , Ácido Desoxicólico/farmacologia , Hifas/efeitos dos fármacos , Polissacarídeo-Liases/farmacologia , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/ultraestrutura , Biofilmes/crescimento & desenvolvimento , Combinação de Medicamentos , Sinergismo Farmacológico , Polissacarídeos Fúngicos/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica
18.
Clin Dev Immunol ; 2013: 403121, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23878583

RESUMO

Invasive candidiasis (IC) represents the leading fungal infection of humans causing life-threatening disease in immunosuppressed and neutropenic individuals including also the intensive care unit patients. Despite progress in recent years in drugs development for the treatment of IC, morbidity and mortality rates still remain very high. Historically, cell-mediated immunity and innate immunity are considered to be the most important lines of defense against candidiasis. Nevertheless recent evidence demonstrates that antibodies with defined specificities could act with different degrees showing protection against systemic and mucosal candidiasis. Mycograb is a human recombinant monoclonal antibody against heat shock protein 90 (Hsp90) that was revealed to have synergy when combined with fluconazole, caspofungin, and amphotericin B against a broad spectrum of Candida species. Furthermore, recent studies have established an important role for Hsp90 in mediating Candida resistance to echinocandins, giving to this antibody molecule even more attractive biological properties. In response to the failure of marketing authorization by the CHMP (Committee for Medicinal Products for Human Use) a new formulation of Mycograb, named Mycograb C28Y variant, with an amino acid substitution was developed in recent years. First data on Mycograb C28Y variant indicate that this monoclonal antibody lacked efficacy in a murine candidiasis model.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antifúngicos/uso terapêutico , Candidíase Invasiva/tratamento farmacológico , Anticorpos Monoclonais Humanizados , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Proteínas Recombinantes/uso terapêutico
19.
J Infect Dis ; 206(6): 952-60, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22782954

RESUMO

Enterococcus faecalis is an established nosocomial pathogen, yet the pathogenesis of enterococcal infections, particularly of urinary tract infections (UTIs), remains to be fully elucidated. Fibronectin-binding proteins have been identified as potent adhesins in pathogenic Gram-positive cocci. Here, we characterized EfbA, which is encoded by the enterococcal orthologue of Streptococcus pneumoniae pavA. Similar to PavA, the anchorless EfbA protein was localized to the enterococcal cell outer surface and bound to immobilized human fibronectin. In addition to abrogated EfbA expression, deletion of the efbA gene eliminated EfbA from the cell surface and drastically reduced the enterococcal cell binding to immobilized fibronectin. The ΔefbA deletion mutant was highly attenuated vs wild-type in a murine ascending UTI model, consistent with an increased tropism for the kidney relative to the bladder. These results provide the first evidence that EfbA of E. faecalis plays a role in UTIs, probably contributing to the pathogenesis in this site.


Assuntos
Proteínas de Bactérias/metabolismo , Enterococcus faecalis/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções Urinárias/microbiologia , Animais , Aderência Bacteriana , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Enterococcus faecalis/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Fibronectinas/metabolismo , Imunofluorescência , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Immunoblotting , Proteínas de Membrana/metabolismo , Camundongos , Microscopia Imunoeletrônica , Ligação Proteica , Proteínas Recombinantes , Virulência
20.
Plants (Basel) ; 12(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679069

RESUMO

BACKGROUND: Candida auris represents an emerging pathogen that results in nosocomial infections and is considered a serious global health problem. The aim of this work was to evaluate the in vitro antifungal efficacy of Cinnamomum cassia essential oil (CC-EO) pure or formulated in polycaprolactone (PCL) nanoparticles against ten clinical strains of C. auris. METHODS: nanoparticles of PCL were produced using CC-EO (nano-CC-EO) and cinnamaldehyde (CIN) through the nanoprecipitation method. The chemical profile of both CC-EO and nano-CC-EO was evaluated using SPME sampling followed by GC-MS analysis. Micro-broth dilution tests were performed to evaluate both fungistatic and fungicidal effectiveness of CC-EO and CIN, pure and nano-formulated. Furthermore, checkerboard tests to evaluate the synergistic action of CC-EO or nano-CC-EO with micafungin or fluconazole were conducted. Finally, the biofilm disrupting activity of both formulations was evaluated. RESULTS: GC-MS analysis shows a different composition between CC-EO and nano-CC-EO. Moreover, the microbiological analyses do not show any variation in antifungal effectiveness either towards the planktonic form (MICCC-EO = 0.01 ± 0.01 and MICnano-CC-EO = 0.02 ± 0.01) or the biofilm form. No synergistic activity with the antifungal drugs tested was found. CONCLUSIONS: both CC-EO and nano-CC-EO show the same antimicrobial effectiveness and are potential assets in the fight against C. auris.

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