Disinfectants and antiseptics lead in reducing the number of microorganisms, including pathogenic ones, thus limiting the number of infections. In the veterinary field, disinfection prevents the transfer of pathogenic microorganisms from animals to humans and , as well as among animals. Several assays of disinfectant antimicrobial activity testing, often not standardized, without appropriate controls, and not validated, have been used and published.
View Article and Find Full Text PDFDespite the urgent need for new antibiotics, very few innovative antibiotics have recently entered clinics or clinical trials. To provide a constant supply of new drug candidates optimized in terms of their potential to select for resistance in natural settings, in vitro resistance-predicting studies need to be improved and scaled up. In this review, the following in vitro parameters are presented: frequency of spontaneous mutant selection (FSMS), mutant prevention concentration (MPC), dominant mutant prevention concentration (MPC-D), inferior-mutant prevention concentration (MPC-F), and minimal selective concentration (MSC).
View Article and Find Full Text PDFRSC Med Chem
May 2024
Benzosiloxaboroles are an emerging class of medicinal agents possessing promising antimicrobial activity. Herein, the expedient synthesis of two novel thiol-functionalized benzosiloxaboroles 1e and 2e is reported. The presence of the SH group allowed for diverse structural modifications involving the thiol-Michael addition, oxidation, as well as nucleophilic substitution giving rise to a series of 27 new benzosiloxaboroles containing various polar functional groups, , carbonyl, ester, amide, imide, nitrile, sulfonyl and sulfonamide, and pendant heterocyclic rings.
View Article and Find Full Text PDFOver 30 compounds, including -, -, and -phenylenediboronic acids, -substituted phenylboronic acids, benzenetriboronic acids, di- and triboronated thiophenes, and pyridine derivatives were investigated as potential β-lactamase inhibitors. The highest activity against KPC-type carbapenemases was found for -phenylenediboronic acid , which at the concentration of 8/4 mg/L reduced carbapenems' MICs up to 16/8-fold, respectively. Checkerboard assays revealed strong synergy between carbapenems and with the fractional inhibitory concentrations indices of 0.
View Article and Find Full Text PDFThe efflux pumps, beside the class D carbapenem-hydrolysing enzymes (CHLDs), are being increasingly investigated as a mechanism of carbapenem resistance in . This study investigates the contribution of efflux mechanism to carbapenem resistance in 61 acquired -genes-carrying clinical strains isolated in Warsaw, Poland. Studies were conducted using phenotypic (susceptibility testing to carbapenems ± efflux pump inhibitors (EPIs)) and molecular (determining expression levels of efflux operon with regulatory-gene and whole genome sequencing (WGS)) methods.
View Article and Find Full Text PDFThe analysis of antimicrobial activity is usually MIC- and minimal bactericidal concentration (MBC)-focused, though also crucial are resistance-related parameters, e.g., the frequency of spontaneous mutant selection (FSMS), the mutant prevention concentration (MPC), and the mutant selection window (MSW).
View Article and Find Full Text PDFLevofloxacin is considered an alternative treatment option of infections to trimethoprim/sulfamethoxazole. The fluoroquinolone resistance in is usually caused by an overproduction of efflux pumps. In this study, the contribution of efflux systems to levofloxacin resistance in clinical isolates was demonstrated using phenotypic (minimal inhibitory concentrations, MICs, of antibiotics determination ± efflux pump inhibitors, EPIs) and molecular (real-time polymerase-chain-reaction and sequencing) methods.
View Article and Find Full Text PDFTwo isomeric benzosiloxaborole derivatives 3a and 5a bearing fluorine and 4,4-dimethyl-2-oxazolin-2-yl substituents attached to the aromatic rings were obtained. Both compounds were prone to hydrolytic cleavage of the oxazoline ring after initial protonation or methylation of the nitrogen atom. The derivative 3c featuring -methylammoniumalkyl ester functionality was successfully subjected to -sulfonylation and -acylation reactions to give respective derivatives which demonstrates its potential for modular synthesis of structurally extended benzosiloxaboroles.
View Article and Find Full Text PDFAn increase of nosocomial infections caused by strains has recently been observed all over the world. The isolation of these bacteria from the blood is of particular concern. In this study we performed the phenotypic and genotypic characterization of 94 isolates, including isolates from patients hospitalized in a tertiary Warsaw hospital ( = 79) and from outpatients ( = 15).
View Article and Find Full Text PDFA series of 22 benzosiloxaboroles, silicon analogues of strong antimicrobial agents - benzoxaboroles, have been synthesized and tested against β-lactamases KPC- and pAmpC-producing strains of Gram-negative rods. Comprehensive structural-property relationship studies supported by molecular modelling as well as biological studies reveal that 6-B(OH)-substituted derivative 27 strongly inhibits the activity of cephalosporinases (chromosomally encoded AmpC and plasmid encoded CMY-2) and KPC carbapenemases. It also shows strong ability to inhibit growth of the strains producing KPC-3 when combined with meropenem.
View Article and Find Full Text PDFNon-antibiotic medicinal products consist of drugs with diverse activity against bacteria. Many non-antibiotics demonstrate direct anti-bacterial activity against Gram-positive cocci. The activity observed against Gram-negative rods is much lower and non-antibiotics primarily from the following groups: non-steroidal anti-inflammatory drugs, cardiovascular and antidepressant medicinal products demonstrate this activity.
View Article and Find Full Text PDFSimplified method for simultaneous identification of proteins, drying oils, waxes, and resins in the works-of-art samples was developed. Liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry were used to identify natural materials most frequently encountered in historical paintings. Protein binders were extracted with ammonia and purified using miniaturized solid-phase microextraction (Omix tips) to efficiently suppress matrix interferences.
View Article and Find Full Text PDFKnowledge of the prevalence of ESBL enzymes among P. aeruginosa strains compared to the Enterobacteraiceae family is limited. The phenotypic tests recommended by EUCAST for the detection of ESBL-producing Enterobacteriaceae are not always suited for P.
View Article and Find Full Text PDFThe potential role of non-antibiotic medicinal products in the treatment of multidrug-resistant Gram-negative bacteria has recently been investigated. It is highly likely that the presence of efflux pumps may be one of the reasons for the weak activity of non-antibiotics, as in the case of some non-steroidal anti-inflammatory drugs (NSAIDs), against Gram-negative rods. The activity of eight drugs of potential non-antibiotic activity, active substance standards, and relevant medicinal products were analysed with and without of efflux pump inhibitors against 180 strains of five Gram-negative rod species by minimum inhibitory concentration (MIC) value determination in the presence of 1 mM MgSO₄.
View Article and Find Full Text PDFBackground: Most patients with bacterial infections suffer from fever and various pains that require complex treatments with antibiotics, antipyretics, and analgaesics. The most common drugs used to relieve these symptoms are non-steroidal anti-inflammatory drugs (NSAIDs), which are not typically considered antibiotics. Here, we investigate the effects of NSAIDs on bacterial susceptibility to antibiotics and the modulation of bacterial efflux pumps.
View Article and Find Full Text PDFChemical composition and antibacterial activity of aqueous (ethanolic and methanolic) extracts from herbs often used in Polish cuisine and traditional herbal medicine including thyme (Thymus vulgaris L.), rosemary (Rosmarinus officinalis L.), oregano (Origanum vulgare L.
View Article and Find Full Text PDFThe production of β-lactamases is the most important mechanism of Gram-negative rod resistance to β-lactams. Resistance to ceftazidime and cefepime in clinical isolates of Enterobacteriaceae (especially ESβL-positive E. coli and K.
View Article and Find Full Text PDFThe reaction of substituted benzylhalides, or of halomethyl derivatives of thiophene or furane, with thiourea or its derivatives yielded the respective isothioureas as hydrohalide salts. The products (a total of 17, including 16 novel compounds) were tested for activity against five Gram-positive and nine Gram-negative bacterial strains, six yeast species and two protozoan species. The most active against Gram-positive bacteria were S-(2,4-dinitrobenzyl)isothiourea hydrochloride (MIC range for four out of five strains tested: 12.
View Article and Find Full Text PDFTwo temperature-sensitive Saccharomyces cerevisiae mutants, sec59-1 and dpm1-6, impaired, respectively, in dolichol kinase (Sec59p) and dolichyl phosphate mannose (DolPMan) synthase (Dpm1p), have an aberrant cell wall structure and composition. We tested their sensitivity to four classes of antifungal drugs used in clinical practice: 5-fluorocytosine, amphotericin B, caspofungin and itraconasole. The strains were resistant to itraconazole and sensitive to the other drugs used.
View Article and Find Full Text PDFA novel isoquinoline alkaloid of molecular formula C10H9NO4, labeled JS-1, was isolated from the culture broth of Streptomyces sp. 8812. It was purified by acetone protein precipitation from the culture supernatant, followed by anion exchange and C18 RP HPLC columns.
View Article and Find Full Text PDFA multistep synthesis of a new analogue of ketoconazole, which was expected to show antifungal and antibacterial activity, has been described.
View Article and Find Full Text PDFA series of new trimethoprim [5-(3,4,5-trimethoxy-benzyl)-pyrimidine-2,4- diamine] analogues were prepared by condensation of adamantane-1-carbaldehyde with 3-methoxypropionitrile, followed by reaction of resulting mixture of 2-adamantan-1-ylmethyl-3-methoxy-acrylonitrile and 3-adamantan-1-yl-2-methoxymethyl-acrylonitrile with guanidine, acetamidine and thiourea, respectively. The activity of compounds obtained and sulfamethoxazole, alone and in combination, against several bacterial strains, as well as fungi was investigated.
View Article and Find Full Text PDFObjective: The aim of our study was to determine what a hazard for patients creates the presence of cockroaches in hospital environment.
Material And Methods: The probable hospital infections cases in 9 hospitals in Warsaw were found in database of the Country Hospital Morbidity Register for the year 2004 and correlation between such factors as: drug resistance of bacteria isolated from external part of cockroach's bodies, their ability to biofilm building, adherence, resistance to disinfectants, resistance of cockroaches to insecticides, infestation level vs. infections of several body systems was examined.
Expression of the Saccharomyces cerevisiae DPM1 gene (coding for dolichylphosphate mannose synthase) in Trichoderma reesei (Hypocrea jecorina) increases the intensity of protein glycosylation and secretion and causes ultrastructural changes in the fungal cell wall. In the present work, we undertook further biochemical and morphological characterization of the DPM1-expressing T. reesei strains.
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