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Search results for: ANTIBIOTIC COMPOUNDS
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Sonocatalytic degradation of tetracycline antibiotic using zinc oxide nanostructures loaded on nano-cellulose from waste straw as nanosonocatalyst
PublicationThe aim of the present investigation was the combination of ZnO nanostructures with nano-cellulose (NC) for the efficient degradation of tetracycline (TC) antibiotic under ultrasonic irradiation. The removal efficiency of 12.8% was obtained by the sole use of ultrasound (US), while the removal efficiency increased up to 70% by the US/ZnO treatment process. Due to the integration of ZnO nanostructures with NC, the removal efficiency...
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The Substantial Improvement of Amphotericin B Selective Toxicity Upon Modification of Mycosamine with Bulky Substituents
PublicationAbstract: Background: It is assumed that the unfavorable selective toxicity of an antifungal drug Amphotericin B (AmB) can be improved upon chemical modification of the antibiotic molecule. Objective: The aim of this study was verification of the hypothesis that introduction of bulky substituents at the amino sugar moiety of the antibiotic may result in diminishment of mammalian vitro toxicity of thus prepared AmB derivatives. Methods:...
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Właściwości katalityczne i biomedyczne związków zawierających jony rutenu(II) oraz rutenu(III)
PublicationRuthenium complexes appear in scientific publications mainly as catalysts in the olefins metathesis process. In this review, we want to indicate the research niche regarding the use of ruthenium(II) and ruthenium(III) complexes in other catalytic processes, i.e. polymerization or epoxidation of olefins and depolymerization. We would like to combine the catalytic properties of ruthenium(II,III) complex compounds with their biomedical...
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Amphotericin B and Its New Derivatives - Mode of Action
PublicationAmphotericin B (AmB) is a well known antifungal and antiprotozoal antibiotic used in the clinic for several decades. Clinicalapplications of AmB, however, are limited by its nephrotoxicity and many other acute side effects which are not acceptable by patientswhen their life is not threaten. In order to improve the therapeutic index of this drug, lipid formulations have been introduced and manyefforts have been made to obtain less...
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Iso-Partricin, an Aromatic Analogue of Amphotericin B: How Shining Light on Old Drugs Might Help Create New Ones
PublicationPartricin is a heptaene macrolide antibiotic complex that exhibits exceptional antifungal activity, yet poor selective toxicity, in the pathogen/host system. It consists of two compounds, namely partricin A and B, and both of these molecules incorporate two cis-type bonds within their heptaenic chromophores: 28Z and 30Z. In this contribution, we have proven that partricins are susceptible to a chromophore-straightening photoisomerization...
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Heptaene macrolides biosynthesis by Streptomyces species
PublicationPolyene macrolides are one of the groups of secondary metabolites, generated by microorganisms belonging to the Streptomyces genus. These compounds, containing 3 - 7 conjugated double bonds systems in their molecules exhibit high antifungal activity against a broad spectrum of fungal pathogens with heptaenes demonstrating the highest antifungal potential. At the large extent, efficiency of biosynthesis of these natural products...
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Comparative molecular modelling of biologically active sterols
PublicationMembrane sterols are targets for a clinically important antifungal agent – amphotericin B. The relatively specific antifungal action of the drug is based on a stronger interaction of amphotericin B with fungal ergosterol than with mammalian cholesterol. Conformational space occupied by six sterols has been defined using the molecular dynamics method to establish if the conformational features correspond to the preferential interaction...
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Evaluating the antibacterial activity of muramyl dipeptide derivatives, retro-tuftsin derivatives, and anthraquinone oligopeptides against a range of pathogenic bacteria
PublicationSearch for new and efficient antibiotic is crucial because of microbial drug resistance and problems with side effects of the administered medication. In this study, we evaluate the in vitro microbiological activity of muramyl dipeptide derivatives, retro-tuftsin derivatives (i.e., tuftsin with reversed amino acid sequences), and combinations of retro-tuftsin derivatives with substituted anthraquinones. The potency of the investigated...
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Anthra[1,2-d][1,2,3]triazine-4,7,12(3H)-triones as a New Class of Antistaphylococcal Agents: Synthesis and Biological Evaluation
PublicationThe development and spread of resistance of human pathogenic bacteria to the action of commonly used antibacterial drugs is one of the key problems in modern medicine. One of the especially dangerous and easily developing antibiotic resistant bacterial species is Staphylococcus aureus. Anthra[1,2-d][1,2,3]triazine-4,7,12(3H)-triones 22–38 have been developed as novel effective antistaphylococcal agents. These compounds have been...
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MXenes Antibacterial Properties and Applications: A Review and Perspective
PublicationThe mutations of bacteria due to the excessive use of antibiotics, and generation of antibiotic-resistant bacteria have made the development of new antibacterial compounds a necessity. MXenes have emerged as biocompatible transition metal carbide structures with extensive biomedical applications. This is related to the MXenes’ unique combination of properties, including multifarious elemental compositions, 2D-layered structure,...
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Diaryl Sulfide Derivatives as Potential Iron Corrosion Inhibitors: A Computational Study
PublicationThe present work aimed to assess six diaryl sulfide derivatives as potential corrosion inhibitors. These derivatives were compared with dapsone (4,4′-diaminodiphenyl sulfone), a common leprosy antibiotic that has been shown to resist the corrosion of mild steel in acidic media with a corrosion efficiency exceeding 90%. Since all the studied compounds possess a common molecular backbone (diphenyl sulfide), dapsone was taken as the...
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Hybrid metal and non-metal activation of Oxone by magnetite nanostructures co-immobilized with nano-carbon black to degrade tetracycline: Fenton and electrochemical enhancement with bio-assay
PublicationElectrochemically synthesized magnetite nanostructures (ESMNPs) as a metal activator and nano-carbon black (NCB) as a non-metal activator were co-immobilized by alginate natural polymer to activate Oxone for the degradation of tetracycline (TC) antibiotic. The formation of sulfate radical was indirectly confirmed during the Oxone/ESMNPs/NCB/alginate process via the addition of scavenging compounds. This study revealed the high...
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Novel Nystatin A1 derivatives exhibiting low host cell toxicity and antifungal activity in an in vitro model of oral candidosis
PublicationOpportunistic oral infections caused by Candida albicans are frequent problems in immunocompromised patients. Management of such infections is limited due to the low number of antifungal drugs available, their relatively high toxicity and the emergence of antifungal resistance. Given these issues, our investigations have focused on novel derivatives of the antifungal antibiotic Nystatin A1, generated by modifications at the amino...
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Antibiotic resistance in wastewater, does the context matter? Poland and Portugal as a case study
PublicationAntibiotic resistance has been considered a major human health threat that may endanger the success of medicine. Recent studies have unveiled worldwide asymmetries of antibiotic resistance occurrence, being factors as diverse as climate, socioeconomic, or antibiotic use possible drivers of such asymmetric distribution. In Europe, where clinical antibiotic resistance is surveyed for more than 20 years, the European Center for Disease...
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Untargeted Lipidomics Reveals Differences in the Lipid Pattern among Clinical Isolates of Staphylococcus aureus Resistant and Sensitive to Antibiotics
PublicationStaphylococcus aureus resistance to antibiotics is a significant clinical problem worldwide. In this study, an untargeted lipidomics approach was used to compare the lipid fingerprints of S. aureus clinical isolates that are resistant and sensitive to antibiotics. High-performance liquid chromatography coupled with time-of-flight mass spectrometry was employed to rapidly and comprehensively analyze bacterial lipids. Chemometric...
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Antibiotic-Based Conjugates Containing Antimicrobial HLopt2 Peptide: Design, Synthesis, Antimicrobial and Cytotoxic Activities
PublicationRecent studies have shown that modified human lactoferrin 20−31 fragment, named HLopt2, possesses antibacterial and antifungal activity. Thus, we decided to synthesize and evaluate the biological activity of a series of conjugates based on this peptide and one of the antimicrobials with proven antibacterial (ciprofloxacin, CIP, and levofloxacin, LVX) or antifungal (fluconazole, FLC) activity. The drugs were covalently connected...
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The Action Mechanisms, Anti-Cancer and Antibiotic-Modulation Potential of Vaccinium myrtillus L. Extract
PublicationHerbal medicinal products containing Vaccinium myrtillus L. (bilberry) fruits and fruit extracts are widely available in the market. Although bilberry leaves and stems are considered as bio-waste, they contain much higher levels of phenolic compounds than fruits. The study aimed to investigate the antimicrobial and anticancer potential of aerial part extracts from Vaccinium myrtillus L. (V. myrtillus, VM) plants harvested at high...
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A global multinational survey of cefotaxime-resistant coliforms in urban wastewater treatment plants
PublicationThe World Health Organization Global Action Plan recommends integrated surveillance programs as crucial strategies for monitoring antibiotic resistance. Although several national surveillance programs are in place for clinical and veterinary settings, no such schemes exist for monitoring antibiotic-resistant bacteria in the environment. In this transnational study, we developed, validated, and tested a low-cost surveillance and...
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Does the chemical modification of Nystatin A1 affect the drug's ability to overcome the multidrug resistance of fungi?
PublicationAlthough the contemporary medicine keeps moving forward, disseminated infections caused by fungal pathogens are an emerging challenge. The dramatic rise of fungal diseases, especially the most life-threatening systemic mycoses is associated with a permanently growing number of immunodeficient patients. Undoubted difficulties in the treatment of fungal infections are caused by lack of highly effective and selective antifungal drugs,...
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Light-Induced Transformation of the Aromatic Heptaene Antifungal Antibiotic Candicidin D into Its All-Trans Isomer
PublicationIllumination of the aromatic heptaene macrolide antifungal antibiotic candicicin D with UV light results in an isomerization of the molecule. The product formed after irradiation of the candicidin complex with UV light (λ=365nm), namely, iso-candicidin D, was isolated and subjected to 2D NMR studies, consisting of DQF-COSY, ROESY, TOCSY, HSQC, and HMBC experiments. The obtained spectral data unambiguously evidenced that iso-candicidin...
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Analysis of the impact of wastewater discharge on recipients: synergistic approach
PublicationThe dissertation presents the analysis of chemical and microbial composition of wastewater and examines the impact of wastewater discharge on the environment. Various case studies were analysed: from small settlements in a pristine European Arctic, to large municipal wastewater treatment plants in areas subjected to greater anthropogenic pressure. In order to comprehensively analyse the impact of wastewater discharge on the receiving...
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The treatment of wastewater containing pharmaceuticals in microcosm constructed wetlands: the occurrence of integrons (int1–2) and associated resistance genes (sul1–3, qacEΔ1)
PublicationThe aim of this study was to analyze the occurrence of sulfonamide resistance genes (sul1–3) and other genetic elements as antiseptic resistance gene (qacEΔ1) and class 1 and class 2 integrons (int1–2) in the upper layer of substrate and in the effluent of microcosm constructed wetlands (CWs) treating artificial wastewater containing diclofenac and sulfamethoxazole (SMX), which is a sulfonamide antibiotic. The bacteria in the substrate...
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Effect of aeration of antibiotic-loaded bone cement on its properties and bactericidal effectiveness
PublicationBACKGROUND: Antibiotic-loaded bone cements are now widely used in medicine. They are able to locally deliver antibiotic particles and they allow treat or protect against infection. It is assumed that the bactericidal effectiveness of bioactive bone cements depend on the parameters of its production. Hence, the aim of this study was to check the effect of aeration of bone cement before mixing the components on its properties as...
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Bee Products and Essential Oils as Alternative Agents for Treatment of Infections Caused by S. aureus
PublicationBacteria of the genus Staphylococcus are important human and veterinary pathogens. A crucial characteristic for this group of bacteria is that they can easily acquire mechanisms of antibiotic resistance for a plethora of antibiotics currently in use for human and animal therapies. Therefore, there is a great need to find novel, non-antibiotic chemotherapeutics with marked antistaphylococcal activity. Promising but still underestimated...
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Influence of a lipid bilayer on the conformational behavior of amphotericin B derivatives - A molecular dynamics study.
PublicationAmphotericin B (AmB) is an effective but very toxic antifungal antibiotic. In our laboratory a series of AmB derivatives of improved selectivity of action was synthesized and tested. To understand molecular basis of this improvement, comparative conformational studies of amphotericin B and its two more selectivederivatives were carried out in an aqueous solution and in a lipid membrane. These molecular simulation studies revealed...
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Stereostructure of mycoheptin A2
PublicationThe absolute configurations of all the stereogenic centers of the antibiotic mycoheptin A2 were established upon previouslyelaborated general procedure, consisting of DQF-COSY, NOESY, ROESY, HSQC and HMBC experiments as major tools. Thestructure of mycoheptin A2 without stereochemistry of its aglycone has been reported before.
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Determination of amikacin and ciprofloxacin by liquid chromatography with pre-column derivatization to evaluate sustained delivery of antibiotics from Drug-Eluting Biopsy Needle
PublicationDetermination of chosen antibacterial antibiotics: amikacin and ciprofloxacin was carried out by HPLC-UV after derivatization with 9-fluorenylmethyl chloroformate and in their native form by HPLC-MS/MS. Developed methods have been applied to control the kinetics of antibiotic release from polymer-based controlled drug delivery system.
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Stereostructure of mycoheptin A2
PublicationThe absolute configurations of all the stereogenic centers of the antibiotic mycoheptin A2 were established upon previously elaborated general procedure, consisting of DQF-COSY, NOESY, ROESY, HSQC and HMBC experiments as major tools. The structure of mycoheptin A2 without stereochemistry of its aglycone has been reported before.
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A new assay for simultaneous identification and differentiation of Klebsiella oxytoca strains
PublicationBacterial strain typing, or identifying bacteria at the strain level, is particularly important for diagnosis, treatment, and epidemiological surveillance of bacterial infections. This is especially the case for bacteria exhibiting high levels of antibiotic resistance or virulence, and those involved in nosocomial or pandemic infections. Strain typing also has applications in studying bacterial population dynamics.
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Lipidomics of Staphylococcus aureus – a new insight into the antibiotic resistant phenotype
PublicationStaphylococcus aureus is an aggressive pathogen responsible for a variety of diseases, in cluding life-threatening sepsis. Many strains of these bacteria are resistant to multiple classes of antibiotics, which is a substantial clinical problem in the treatment of S. aureus infections. We developed a comprehensive untargeted lipidomic workflow, including sample preparation, liquid chromatography-quadrupole-time-of-flight mass spectrometry...
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Intramolecular transformation of an antifungal antibiotic nystatin A1 into its isomer, iso-nystatin A1 - structural and molecular modeling studies
PublicationNystatin A1, a polyene macrolide antifungal antibiotic, in a slightly basic or acidic solution undergoes an intramolecular transformation, yielding a structural isomer, the translactonization product, iso-nystatin A1 with lactone ring diminished by two carbon atoms. Structural evidence is provided by advanced NMR and Mass Spectrometry (MS) studies. Molecular dynamics simulations and quantum mechanics calculations gave the insight...
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The structure, including stereochemistry, of levorin A1
PublicationThe constitution and stereostructure of levorin A1 1, an aromatic heptaeneantifungal antibiotic, was established on the basis of NMR studies, which contained DQFCOSY,ROESY, HSQC and HMBC experiments. Mycosamine moiety was used as an internalchiral probe to determine the absolute configuration of levorin A1 stereogenic centers: 13S,15R, 17S, 18R, 19S, 21R. The relative configuration of the remaining stereogenic centers wasassigned...
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Determination of antibiotic residues in honey
PublicationHoney produced by honeybees is a valuable food product. The presence of xenobiotics in honey may harm its quality and constitute a danger to human health. Antibiotics are commonly applied by beekeepers to eliminate disease among honeybees. Moreover, ubiquitous administration of antibiotics may cause bacteria to become resistant to many drugs and spread antibioticresistant strains of bacteria. Appropriate sample preparation and...
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Polyurethanes as a carrier of drugs for gentamicin
PublicationGentamicin is one of the most popular drug and is widely used due to its antibiotic properties. 3% of world production of polyurethanes (PU) is dedicated to biomedical applications, where they can serve are parts of orthopedic prosthesis or artificial organs, disposable medical devices, wound and burn dressing, contact lenses among others. In the study, to obtain drug carriers, a combination of these two materials were prepared...
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Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020
PublicationThe aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January–June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. Escherichia coli (52.2%), Klebsiella pneumoniae (13.7%), Enterococcus faecalis (9.3%), E. faecium (6.2%), and Proteus mirabilis (4,3%) were...
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Turmeric nanofiber-encapsulated natural product formulation act as a phytogenic feed additive—A study in broilers on growth performance, biochemical indices of blood, and E. coli in cecum
PublicationA phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased...
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Molecular Umbrellas Modulate the Selective Toxicity of Polyene Macrolide Antifungals
PublicationAntifungal polyene macrolide antibiotics Amphotericin B (AmB) and Nystatin (NYS) were conjugated through the ω-amino acid linkers with diwalled “molecular umbrellas” composed of spermidine-linked deoxycholic or cholic acids. The presence of “umbrella” substituents modulated biological properties of the antibiotics, especially their selective toxicity. Some of the AmB-umbrella conjugates demonstrated antifungal in vitro activity...
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Antibiotic resistance in Staphylococcus aureus strains isolated from cows with mastitis in the eastern Poland and analysis of susceptibility of resistant strains to alternative non-antibiotic agents: lysostaphin, nisin and polymyxin B.
PublicationThe aim of the studies was analysis of resistance of Staphylococcus aureus isolates from bovine mastitis in eastern part of Poland to a set of 20 antibiotics and three alternative agents: lysostaphin, nisin and polymyxin B. Eighty-six out of 123 examined isolates were susceptible to all of 20 tested antibiotics (70 %). The highest percentage of resistance was observed in the case of β-lactam antibiotics: amoxicillin (n=22, 17.9...
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Pharmaceuticals and other contaminants of emerging concern in Admiralty Bay as a result of untreated wastewater discharge: Status and possible environmental consequences
PublicationConsidering how the impact of human activity in Antarctica is growing, the aim of this study was to conduct the first assessment of pharmaceuticals and personal care products (PPCPs), other emerging contaminants (ECs), and antibiotic resistance genes present in the western shore of the Admiralty Bay region of King George Island. In total, more than 170 substances were evaluated to assess the potential environmental risks they pose...
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The complete stereochemistry of the antibiotic candicidin A3 (syn. ascosin A3, levorin A3)
PublicationHerein, the stereostructure of the aromatic heptaene macrolide (AHM) antifungal antibiotic candicidin A3 (syn. ascosin A3, levorin A3) has been established upon the 2D NMR studies, consisting of DQF-COSY, TOCSY, ROESY, HSQC and HMBC experiments, as well as upon extensive molecular dynamics simulations. The geometry of the heptaenic chromophore was defined as: (22E, 24E, 26Z, 28Z, 30E, 32E, 34E). The previously unreported absolute...
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Mechanism of Binding of Antifungal Antibiotic Amphotericin B to Lipid Membranes: An Insight from Combined Single-Membrane Imaging, Microspectroscopy, and Molecular Dynamics
PublicationAmphotericin B is a lifesaving polyene antibiotic used in the treatment of systemic mycoses. Unfortunately, the pharmacological applicability of this drug is limited because of its severe toxic side effects. At the same time, the lack of a well-defined mechanism of selectivity hampers the efforts to rationally design safer derivatives. As the drug primarily targets the biomembranes of both fungi and humans, new insights into the...
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Detection of sulfonamide resistance genes via in situ PCR-FISH
PublicationDue to the rising use of antibiotics and as a consequence of their concentration in the environment an increasing number of antibiotic resistant bacteria is observed. The phenomenon has a hazardous impact on human and animal life. Sulfamethoxazole is one of the sulfonamides commonly detected in surface waters and soil. The aim of the study was to detect sulfamethoxazole resistance genes in activated sludge biocenosis by use of...
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Antibiotic resistance, virulence, and phylogenetic analysis of Escherichia coli strains isolated from free-living birds in human habitats
PublicationWild birds can be colonized by bacteria, which are often resistant to antibiotics and have various virulence profiles. The aim of this study was to analyze antibiotic resistance mechanisms and virulence profiles in relation to the phylogenetic group of E. coli strains that were isolated from the GI tract of wildfowl. Out of 241 faecal samples, presence of E. coli resistant to a cephalosporin (ESBL/AmpC) was estimated for 33 isolates...
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Ciprofloxacin-modified degradable hybrid polyurethane-polylactide porous scaffolds developed for potential use as an antibacterial scaffold for regeneration of skin
PublicationThe aim of the performed study was to fabricate an antibacterial and degradable scaffold that may be used in the field of skin regeneration. To reach the degradation criterion for the biocompatible polyurethane (PUR), obtained by using amorphous α,ω-dihydroxy(ethylene-butylene adipate) macrodiol (PEBA), was used and processed with so-called “fast-degradable” polymer polylactide (PLA) (5 or 10 wt %). To meet the antibacterial requirement...
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Greenness assessment of analytical methods used for antibiotic residues determination in food samples
PublicationFood of animal origin plays an important role in ensuring a healthy and sustainable human diet. However, residues of pharmaceuticals, especially antibiotics, can be the cause of many health problems. To protect consumers and improve food quality, analytical methods used to determine contaminants should be simple, selective, and have high throughput and low detection limits. Recently, greenness metric tools have proven useful in...
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Natural Products Counteracting Cardiotoxicity during Cancer Chemotherapy: The Special Case of Doxorubicin, a Comprehensive Review
PublicationCardiotoxicity is a frequent undesirable phenomenon observed during oncological treatment that limits the therapeutic dose of antitumor drugs and thus may decrease the effec-‐‑ tiveness of cancer eradication. Almost all antitumor drugs exhibit toxic properties towards cardiac muscle. One of the underlying causes of cardiotoxicity is stimulation of oxidative...
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Quest for the Molecular Basis of Improved Selective Toxicity of All-Trans Isomers of Aromatic Heptaene Macrolide Antifungal Antibiotics
PublicationThree aromatic heptaene macrolide antifungal antibiotics, Candicidin D, Partricin A (Gedamycin) and Partricin B (Vacidin) were subjected to controlled cis-trans to all trans photochemical isomerization. The obtained all-trans isomers demonstrated substantially improved in vitro selective toxicity in the Candida albicans cells: human erythrocytes model. This effect was mainly due to the diminished hemotoxicity. The molecular modeling...
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Linezolid-resistant Enterococcus faecium strains isolated from one hospital in Poland –commensals or hospital-adapted pathogens?
PublicationOne of the most pressing problems of enterococci infections is occurring resistance to linezolid, which is an antibiotic used in the treatment of infections caused by vancomycin-resistant strains (VRE). The main objective of our research was to investigate the relationship of 19 linezolid-resistant E. faecium isolates from 18 patients hospitalized at Clinical Hospital in Gdansk (Poland). One of the LZDREF was isolated in 2003...
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Implant system for treatment of the orbital floor defects of blowout fractures in the maxillofacial region using polypropylene yarn and bioactive bone cement
PublicationFractures in the craniofacial region are a serious problem in terms of treatment. The most reasonable solution is the use of individual implants dedicated to a specific patient. The aim of this study was to develop the implant system specifically for treatment of the orbital floor defects of blowout fractures of maxillofacial region, using polypropylene yarn and bone cement. Three types of bone cement were used to fix the polypropylene...
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Self-Association of Amphotericin B: Spontaneous Formation of Molecular Structures Responsible for the Toxic Side Effects of the Antibiotic
PublicationAmphotericin B (AmB) is a lifesaving antibiotic used to treat deep-seated mycotic infections. Both the pharmaceutical activity and highly toxic side effects of the drug rely on its interaction with biomembranes, which is governed by the molecular organization of AmB. In the present work we present detailed analysis of self-assembly of AmB molecules in different environments, interesting from the physiological standpoint, based...