Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and ...poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.
Many traditional remedies represent potential candidates for integration with modern medical practice, but credible data on their activities are often scarce. For the first time, the anti-virulence ...potential and the safety for human use of the ethanol extracts of two medicinal plants,
(PEM) and
(BIO), have been addressed. Ethanol extracts of both plants exhibited anti-virulence activity against the medically important opportunistic pathogen
. At the subinhibitory concentration of 50 µg/mL, the extracts demonstrated a maximal inhibitory effect (approx. 50%) against biofilm formation, the highest reduction of pyocyanin production (47% for PEM and 59% for BIO) and completely halted the swarming motility of
. Both extracts demonstrated better anti-quorum sensing and antibiofilm activities, and a better ability to interfere with LasR receptor, than the tested dominant extracts' constituents. The bioactive concentrations of the extracts were not toxic in the zebrafish model system. This study represents an initial step towards the integration of
and
for use in the treatment of
infections.
The aim of the study was to evaluate and adapt the PCR-based protocol that utilizes the developed serotype-specific primers to identify
species and its serotypes that are most frequently isolated ...from poultry samples in Vojvodina. Using the slide agglutination test, 64 and 33 out of 107
isolates were identified as
. Infantis and
. Enteritidis, respectively, while ten isolates were identified as eight different
serovars. Using the same isolates, presence of 993-bp (
gene), 636-bp (
gene) and 293-bp (sdf locus) amplicons in multiplex PCR unambiguously identified 31 isolates as
. Enteritidis. Two isolates identified as Enteritidis in slide agglutination test were not identified as such in PCR-based approach since they both were missing 293-bp long PCR product. Thirty-nine isolates produced a 727-bp amplicon in the specific simplex PCR, and thus were identified as
. Infantis. The greatest discrepancy in comparison to the results of conventional serotyping has been observed in the case of
. Infantis, since 25 more isolates were noted as
. Infantis by conventional serotyping. Seven isolates, with unexpected PCR profiles stayed unidentified by molecular typing, although they were serotyped as
. Typhimurium (1) and
. Infantis (6).
. Gallinarum serovar has to be additionally confirmed, since it shares the same PCR profile with
. Livingstone. Clearly, PCR-based identification has to be thoroughly checked, verified and adapted if it is to be applied as the routine identification protocol.
The growing demand to fulfill the needs of present-day medicine in terms of novel effective molecules has lead to reexamining some of the old and known bacterial secondary metabolites. Bacterial ...prodigiosins (prodiginines) have a long history of being re markable multipurpose compounds, best examined for their anticancer and antimalarial activities. Production of prodigiosin in the most common producer strain Serratia marcescens has been described in great detail. However, few reports have discussed the ecophysiological roles of these molecules in the producing strains, as well as their antibiotic and UV-protective properties. This review describes recent advances in the production process, biosynthesis, properties, and applications of bacterial prodigiosins. Special emphasis is put on undecylprodigiosin which has generally been a less studied member of the prodigiosin family. In addition, it has been suggested that proteins involved in undecylprodigiosin synthesis, RedG and RedH, could be a useful addition to the biocatalytic toolbox being able to mediate regio- and stereoselective oxidative cyclization. Judging by the number of recent references (216 for the 2007–2013 period), it has become clear that undecylprodigiosin and other bacterial prodigiosins still hold surprises in terms of valuable properties and applicative potential to medical and other industrial fields and that they still deserve continuing research curiosity.
A new strain, namely
sp. BV152.1 was isolated from the rhizosphere of ground ivy (
L.) producing metabolites with potent ability to inhibit biofilm formation of an important human pathogens
PAO1,
, ...and
. Structural characterization revealed di-rhamnolipids mixture containing rhamnose (Rha)-Rha-C10-C10, Rha-Rha-C8-C10, and Rha-Rha-C10-C12 in the ratio 7:2:1 as the active principle. Purified di-rhamnolipids, as well as commercially available di-rhamnolipids (Rha-Rha-C10-C10, 93%) were used as the substrate for the chemical derivatization for the first time, yielding three semi-synthetic amide derivatives, benzyl-, piperidine-, and morpholine. A comparative study of the anti-biofilm, antibacterial and cytotoxic properties revealed that di-Rha from
sp. BV152.1 were more potent in biofilm inhibition, both cell adhesion and biofilm maturation, than commercial di-rhamnolipids inhibiting 50% of
PAO1 biofilm formation at 50 μg mL
and 75 μg mL
, respectively. None of the di-rhamnolipids exhibited antimicrobial properties at concentrations of up to 500 μg mL
. Amide derivatization improved inhibition of biofilm formation and dispersion activities of di-rhamnolipids from both sources, with morpholine derivative being the most active causing more than 80% biofilm inhibition at concentrations 100 μg mL
. Semi-synthetic amide derivatives showed increased antibacterial activity against
, and also showed higher cytotoxicity. Therefore, described di-rhamnolipids are potent anti-biofilm agents and the described approach can be seen as viable approach in reaching new rhamnolipid based derivatives with tailored biological properties.
Bacterial infections have become increasingly difficult to treat due to the occurrence of antibiotic-resistant strains. A promising strategy to increase the efficacy of therapy is to combine ...antibacterials with agents that decrease pathogen virulence
via
the modulation of the quorum sensing (QS). Lactonases inhibit acylated homoserine lactone (AHL)-mediated QS in Gram-negative bacteria, including the leading nosocomial pathogen
Pseudomonas aeruginosa
. Here we describe the characteristics of heterologously expressed YtnP lactonase from
Bacillus paralicheniformis
ZP1 (YtnP-ZP1) isolated from agricultural soil using the culture enrichment method. Purified YtnP-ZP1 hydrolyzed different AHLs with preference to substrates with long acyl residues as evaluated in assays with biosensors and HPLC. The enzyme showed good thermostability and activity in a wide temperature range. YtnP-ZP1 in 50 μg mL
–1
concentration reduced the amount of
P. aeruginosa
-produced long-chain AHLs by 85%, while it hydrolyzed 50% of short-chain AHLs. Incubation of
P. aeruginosa
PAO1 with YtnP-ZP1 reduced its swarming motility and elastolytic activity without bactericidal effect. YtnP-ZP1 caused the inhibition of biofilm formation and disintegration of mature biofilms in
P. aeruginosa
PAO1 and multiresistant clinical strain BR5H that was visualized by crystal violet staining. The treatment with YtnP-ZP1 in concentrations higher than 25 μg mL
–1
improved the survival of
P. aeruginosa
PAO1-infected zebrafish (
Danio rerio
), rescuing 80% of embryos, while in combination with tobramycin or gentamicin survival rate increased to 100%. The treatment of
P. aeruginosa
PAO1 biofilms on infected zebrafish tail wounds with 50 μg mL
–1
YtnP-ZP1 and 2 × MIC tobramycin led to infection clearing in 2 days. The extensive toxicity studies proved YtnP-ZP1 was non-toxic to human cells and zebrafish. In conclusion, novel YtnP-ZP1 lactonase with its effective anti-virulence activity could be used to increase the efficacy of clinically approved antibiotics in clearing both systemic and biofilm-associated
P. aeruginosa
infections.
This study investigates the modification of commercial cellulose acetate microfiltration membranes by supercritical solvent impregnation with thymol to provide them with antibacterial properties. The ...impregnation process was conducted in a batch mode, and the effect of pressure and processing time on thymol loading was followed. The impact of the modification on the membrane's microstructure was analyzed using scanning electron and ion-beam microscopy, and membranes' functionality was tested in a cross-flow filtration system. The antibiofilm properties of the obtained materials were studied against
and
, while membranes' blocking in contact with bacteria was examined for
and
. The results revealed a fast impregnation process with high thymol loadings achievable after just 0.5 h at 15 MPa and 20 MPa. The presence of 20% of thymol provided strong antibiofilm properties against the tested strains without affecting the membrane's functionality. The study showed that these strong antibacterial properties could be implemented to the commercial membranes' defined polymeric structure in a short and environmentally friendly process.
Candidiasis caused by Candida albicans is one of the most common fungal infections in modern society. The limited arsenal of clinical drugs, their side effects and emerging resistance, largely ...contribute to the low efficacy of current antifungal therapies. The morphogenetic yeast-to-hyphae transition is the key virulence feature for the establishment of local and systemic C. albicans infections. We show that a delfinidin-rich fruit extract from Aristotelia chilensis (Molina, Stuntz) (maqui berry) inhibits filamentation of C. albicans, in both laboratory and clinical strains. The extract acts synergistically with nystatin, with filament formation completely prevented by the combination of ¼×MIC of nystatin and 0.125 mg/ml of the extract. The combination treatment results in increased survival of C. albicans-infected zebrafish embryos compared to treatment with nystatin. Neither the extract nor its combination with nystatin was toxic at effective doses. These results warrant further investigation of maqui berry extract as adjuvant antifungal treatment.
Chokeberry (Aronia melanocarpa) fruit extracts (CE) are rich in polyphenols and usually exhibit immunomodulatory, anti-viral and anti-bacterial effects. We have previously shown that the CE used in ...this study activated macrophages and stimulated effector T cell differentiation in vitro. When applied orally to healthy mice, CE increased the proportion of CD11c+ dendritic cells in the gut-associated lymphoid tissue. CE-pretreated BALB/c mice readily eradicated orally ingested Listeria monocytogenes as evidenced by a slighter decrease in body weight and number of bacteria recovered from the spleen and reduced spleen size compared to the control infected mice. CE pretreatment in infected mice resulted in higher proportions of CD11b+ macrophages and CD8+ cytotoxic T cells both in the gut and the spleen. Phagocytosis, reactive oxygen species production and the proportions of activated CD86+ macrophages (CD11b+) and dendritic cells (CD11c+) were also enhanced in CE-pretreated infected mice. Furthermore, the expression of inducible nitric oxide synthase and IL-6 was increased in CE-pretreated infected mice and similar results were obtained in peritoneal macrophages in vitro. This effect of CE was associated with increased phosphorylation of IκB and Notch1 production. Finally, CE pretreatment elevated the proportion of perforin-producing cells in the spleen compared to control infected mice. This study demonstrates that prophylactic treatment with CE leads to more rapid eradication of bacterial infection with L. monocytogenes predominantly through increased activity of myeloid cells in the gut and in the spleen.
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A series of new thiophene-based guanylhydrazones (iminoguanidines) were synthesized in high yields using a straightforward two-step procedure. The antifungal activity of compounds was ...evaluated against a wide range of medicaly important fungal strains including yeasts, molds, and dermatophytes in comparison to clinically used drug voriconazole. Cytotoxic properties of compounds were also determined using human lung fibroblast cell line and hemolysis assay. All guanylhydrazones showed significant activity against broad spectrum of clinically important species of Candida spp., Aspergillus fumigatus, Fusarium oxysporum, Microsporum canis and Trichophyton mentagrophytes, which was in some cases comparable or better than activity of voriconazole. More importantly, compounds 10, 11, 13, 14, 18 and 21 exhibited excellent activity against voriconazole-resistant Candida albicans CA5 with very low minimal inhibitory concentration (MIC) values <2μgmL−1. Derivative 14, bearing bromine on the phenyl ring, was the most effective compound with MICs ranging from 0.25 to 6.25μgmL−1. However, bis-guanylhydrazone 18 showed better selectivity in terms of therapeutic index values. In vivo embryotoxicity on zebrafish (Danio rerio) showed improved toxicity profile of 11, 14 and 18 in comparison to that of voriconazole. Most guanylhydrazones also inhibited C. albicans yeast to hyphal transition, essential for its biofilm formation, while 11 and 18 were able to disperse preformed Candida biofilms. All guanylhydrazones showed the equal potential to interact with genomic DNA of C. albicans in vitro, thus indicating a possible mechanism of their action, as well as possible mechanism of observed cytotoxic effects. Tested compounds did not have significant hemolytic effect and caused low liposome leakage, which excluded the cell membrane as a primary target. On the basis of computational docking experiments using both human and cytochrome P450 from Candida it was concluded that the most active guanylhydrazones had minimal structural prerequisites to interact with the cytochrome P450 14α-demethylase (CYP51). Promising guanylhydrazone derivatives also showed satisfactory pharmacokinetic profile based on molecular calculations.
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