LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 7 of total 7

Search options

  1. Article ; Online: Design, Synthesis, Antibacterial Evaluations and In Silico Studies of Novel Thiosemicarbazides and 1,3,4-Thiadiazoles

    Sara Janowska / Dmytro Khylyuk / Sylwia Andrzejczuk / Monika Wujec

    Molecules, Vol 27, Iss 3161, p

    2022  Volume 3161

    Abstract: The emergence of drug-resistant bacterial strains continues to be one of the major challenges of medicine. For this reason, the importance of searching for novel structures of antibacterial drugs chemically different from the currently known antibiotics ... ...

    Abstract The emergence of drug-resistant bacterial strains continues to be one of the major challenges of medicine. For this reason, the importance of searching for novel structures of antibacterial drugs chemically different from the currently known antibiotics is still of great importance. In this study, we synthesized the thiosemicarbazide and 1,3,4-thiadiazole derivatives and tested them for antibacterial activity. In in vitro tests, we examined the activity of the synthesized substances against Gram-positive and Gram-negative bacteria strains. While all 1,3,4-thiadiazoles tested lacked significant activity, the antimicrobial response of the thiosemicarbazides was moderate and it was also dependent on the type and position of the substituent on the phenyl ring. The highest activity towards all Gram-positive bacteria strains was shown by all three linear compounds containing the trifluoromethylphenyl group in the structure. The MIC (minimum inhibitory concentration) values were in the range of 3.9–250 µg/mL. Additionally, we try to explain the mechanism of the antibacterial activity of the tested compounds using the molecular docking to DNA gyrase and topoisomerase IV, following previous reports on the molecular basis of the activity of thiosemicarbazides. Docking simulations allow the purposing dual mechanism of the antibacterial activity of the synthesized compounds through inhibition of topoisomerase IV DNA gyrase with the moderate prevalence of the topoisomerase pathway.
    Keywords synthesis ; thiosemicarbazide ; 1,3,4-thiadiazole ; antibacterial activity ; Organic chemistry ; QD241-441
    Subject code 540
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  2. Article ; Online: Prevalence of Culturable Bacteria and Yeasts in the Nasopharynx Microbiota during the Physiological Course of Pregnancy

    Urszula Kosikowska / Dominik Franciszek Dłuski / Dorota Pietras-Ożga / Bożena Leszczyńska-Gorzelak / Sylwia Andrzejczuk

    Journal of Clinical Medicine, Vol 12, Iss 4447, p

    2023  Volume 4447

    Abstract: The aim of the study was to compare the prevalence of the nasopharyngeal carriage of culturable microorganisms in the microbiota of asymptomatic women with a physiological pregnancy (PW) and nonpregnant women (NPW). Nasopharyngeal swabs were collected ... ...

    Abstract The aim of the study was to compare the prevalence of the nasopharyngeal carriage of culturable microorganisms in the microbiota of asymptomatic women with a physiological pregnancy (PW) and nonpregnant women (NPW). Nasopharyngeal swabs were collected from 53 PW and 30 NPW to detect bacterial and fungal colonization. Isolates were identified using the culture method and the MALDI-TOF MS technique. The nasopharyngeal microbiota (NPM) partially differed between PW and NPW. These differences in the frequency of nasopharyngeal colonization between the PW and NPW groups were not statistically significant ( p > 0.05); all cases were colonized by bacteria and only two cases in the PW group were colonized by yeasts, namely, Rhodotorula spp. High levels of staphylococcal colonization, including predominantly coagulase-negative staphylococci and S. aureus in the nasopharyngeal sample, were present in both groups. The reduced number of Gram-negative rods colonized in the cases studied was seen in samples from the NPW group, particularly with Enterobacterales , and anaerobic Cutibacterium spp. were isolated only in the PW group ( p < 0.05). Moreover, a higher carriage rate of Enterobacter aerogenes colonization was statistically significant ( p < 0.05) and correlated with the NPW group. Pregnancy may disturb the composition of the NPM represented by commensals and opportunistic bacteria and promote yeast colonization as compared to nonpregnant women.
    Keywords asymptomatic patients ; bacterial colonization ; yeast colonization ; nasopharyngeal microbiota ; opportunistic pathogens ; pregnancy ; Medicine ; R
    Subject code 630
    Language English
    Publishing date 2023-07-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  3. Article ; Online: Influence of Thiazolidine-2,4-Dione Derivatives with Azolidine or Thiosemicarbazone Moieties on Haemophilus spp. Planktonic or Biofilm-Forming Cells

    Nazar Trotsko / Urszula Kosikowska / Sylwia Andrzejczuk / Agata Paneth / Monika Wujec

    Molecules, Vol 24, Iss 6, p

    2019  Volume 1051

    Abstract: Biofilm, naturally formed by microorganisms as integrated surface-bound communities, is one of the reasons for the development of antimicrobial resistance. Haemophilus spp. are common and representative opportunistic Gram-negative rods forming from the ... ...

    Abstract Biofilm, naturally formed by microorganisms as integrated surface-bound communities, is one of the reasons for the development of antimicrobial resistance. Haemophilus spp. are common and representative opportunistic Gram-negative rods forming from the upper respiratory tract microbiota. The aim of this paper was to evaluate the influence of thiazolidine-2,4-dionebased azolidine and chlorophenylthiosemicarbazone hybrids against both planktonic and biofilm-forming Haemophilus spp. cells. The in vitro activity against planktonic and biofilm-forming cells of the tested compounds were evaluated by using the broth microdilution method. These activities were detected against reference and clinical strains of Haemophilus spp. on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The target compounds showed potential activity against planktonic cells with MIC = 62.5–500 mg/L and biofilm-forming cells with MBIC = 62.5–1000 mg/L. The observed anti-adhesive properties of the tested compounds were reversible during long-term incubation in a lower concentration of compounds.
    Keywords Haemophilus spp ; thiazolidine-2,4-dione based azolidine and chlorophenylthiosemicarbazone hybrids ; anti-planktonic and antibiofilm activity ; anti-adhesive properties ; Organic chemistry ; QD241-441
    Subject code 540
    Language English
    Publishing date 2019-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  4. Article ; Online: Prevalence of Resistance to β-Lactam Antibiotics and bla Genes Among Commensal Haemophilus parainfluenzae Isolates from Respiratory Microbiota in Poland

    Sylwia Andrzejczuk / Urszula Kosikowska / Edyta Chwiejczak / Dagmara Stępień-Pyśniak / Anna Malm

    Microorganisms, Vol 7, Iss 10, p

    2019  Volume 427

    Abstract: 1) Background: Beta-lactams are the most frequently used antimicrobials, and are the first-line drugs in many infectious diseases, e.g., pneumonia, otitis media. Due to this fact, various bacteria have developed resistance to this group of drugs. (2) ... ...

    Abstract (1) Background: Beta-lactams are the most frequently used antimicrobials, and are the first-line drugs in many infectious diseases, e.g., pneumonia, otitis media. Due to this fact, various bacteria have developed resistance to this group of drugs. (2) Methods: Eighty-seven Haemophilus parainfluenzae isolates were obtained from adults 18−70 years old in eastern Poland. The presence of 10 bla genes and 2 substitutions in ftsI reported as the most frequent in H. parainfluenzae were analyzed. (3) Results: Among 57 beta-lactam-resistant isolates, 63.2% encoded bla genes; bla TEM-1 predominated (54.4%), followed by bla OXA (19.3%), bla DHA (12.3%), bla SHV (10.5%), bla GES (7.0%), bla CMY (5.3%), bla VEB (1.8%) and bla ROB-1 (1.8%). Lys-526 was the most common substitution in ftsI gene. The resistance genotypes were as follows: gBLNAS (17.5%), low-gBLNAR I (1.8%), low-gBLNAR II (1.8%), gBLNAR II (15.8%), gBLPAS (15.8%), gBLPAR (19.3%), gBLPBS I (8.8%) and gBLPBS II (1.8%); (4) Conclusions: This has been the first study to report on the high diversity of bla genes in H. parainfluenzae isolates in Poland. High sensitivity and specificity of benzylpenicillin test, as well as PCR of bla genes were shown, indicating that these methods may be useful as tools for the rapid screening of beta-lactamase prevalence and resistance to beta-lactams among H. parainfluenzae isolated from respiratory microbiota.
    Keywords haemophilus parainfluenzae ; beta-lactam resistance ; bla genes ; ftsi ; Biology (General) ; QH301-705.5
    Subject code 610
    Language English
    Publishing date 2019-10-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  5. Article: Inhibitory effect of 1,2,4-triazole-ciprofloxacin hybrids on Haemophilus parainfluenzae and Haemophilus influenzae biofilm formation in vitro under stationary conditions

    Kosikowska, Urszula / Anna Malm / Sylwia Andrzejczuk / Tomasz Plech

    Institut Pasteur Research in microbiology. 2016 Oct., v. 167, no. 8

    2016  

    Abstract: Haemophilus parainfluenzae and Haemophilus influenzae, upper respiratory tract microbiota representatives, are able to colonize natural and artificial surfaces as biofilm. The aim of the present study was to assay the effect of ten 1,2,4-triazole- ... ...

    Abstract Haemophilus parainfluenzae and Haemophilus influenzae, upper respiratory tract microbiota representatives, are able to colonize natural and artificial surfaces as biofilm. The aim of the present study was to assay the effect of ten 1,2,4-triazole-ciprofloxacin hybrids on planktonic or biofilm-forming haemophili cells in vitro under stationary conditions on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The reference strains of H. parainfluenzae and H. influenzae were included. The broth microdilution microtiter plate (MTP) method with twofold dilution of the compounds, or ciprofloxacin (reference agent) in 96-well polystyrene microplates, was used. The optical density (OD) reading was made spectrophotometrically at a wavelength of 570 nm (OD570) both to measure bacterial growth and to detect biofilm-forming cells under the same conditions with 0.1% crystal violet. The following values of parameters were estimated for 1,2,4-triazole-ciprofloxacin hybrids – MIC = 0.03–15.63 mg/L, MBIC = 0.03–15.63 mg/L, MBIC/MIC = 0.125–8, depending on the compound, and for ciprofloxacin – MIC = 0.03–0.06 mg/L, MBIC = 0.03–0.12 mg/L, MBIC/MIC = 1–2. The observed strong anti-adhesive properties (95–100% inhibition) of the tested compounds were reversible during long-term incubation at subinhibitory concentrations.Thus, 1,2,4-triazole-ciprofloxacin hybrids may be considered as starting compounds for designing improved agents not only against planktonic but also against biofilm-forming Haemophilus spp. cells.
    Keywords absorbance ; biofilm ; ciprofloxacin ; gentian violet ; Haemophilus influenzae ; Haemophilus parainfluenzae ; microbial growth ; microorganisms ; minimum inhibitory concentration ; plankton ; polystyrenes ; respiratory system ; wavelengths
    Language English
    Dates of publication 2016-10
    Size p. 647-654.
    Publishing place Elsevier Masson SAS
    Document type Article
    ZDB-ID 1004220-9
    ISSN 1769-7123 ; 0923-2508
    ISSN (online) 1769-7123
    ISSN 0923-2508
    DOI 10.1016/j.resmic.2016.05.009
    Database NAL-Catalogue (AGRICOLA)

    Full text online

    More links

    Kategorien

    In stock of ZB MED Bonn / Germany

    Z 63/179 A/B: Show issues

    Order via subito

    This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  6. Article ; Online: Antibiotic Resistance and Genotypes of Helicobacter pylori Strains in Patients with Gastroduodenal Disease in Southeast Poland

    Izabela Korona-Glowniak / Halina Cichoz-Lach / Radoslaw Siwiec / Sylwia Andrzejczuk / Andrzej Glowniak / Przemyslaw Matras / Anna Malm

    Journal of Clinical Medicine, Vol 8, Iss 7, p

    2019  Volume 1071

    Abstract: The aim of this study was to investigate genetic diversity of Helicobacter pylori virulence markers to predict clinical outcome as well as to determine an antibiotic susceptibility of H. pylori strains in Poland. Gastric biopsies from 132 patients with ... ...

    Abstract The aim of this study was to investigate genetic diversity of Helicobacter pylori virulence markers to predict clinical outcome as well as to determine an antibiotic susceptibility of H. pylori strains in Poland. Gastric biopsies from 132 patients with gastrointestinal disorders were tested for presence of H. pylori with the use of rapid urease test, microbial culture, and polymerase chain reaction (PCR) detection. The genetic diversity of 62 H. pylori positive samples was evaluated by detection of cagA and PCR-typing of vacA and iceA virulence-associated genes. Most common H. pylori genotypes were cagA (+) vacAs1m2 (27.4%) and cagA (−) vacAs2m2 (24.2%). In logistic regression analysis, we recognized the subsequent significant associations: gastritis with ureC , i.e., H. pylori infection ( p = 0.006), BMI index ( p = 0.032); and negatively with iceA1 ( p = 0.049) and peptic ulcer with cagA ( p = 0.018). Thirty-five H. pylori strains were cultured and tested by E-test method showing that 49% of strains were resistant to at least one of the tested antibiotics. This is the first study that reports the high incidence and diversity of allelic combination of virulence genes in gastroduodenitis patients in Poland. Genotyping of H. pylori strains confirmed the involvement of cagA gene and vacAs1m1 genotype in development and severity of gastric disorder.
    Keywords pylorus infection ; cagA ; vacA ; iceA ; antibiotic patterns ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2019-07-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

  7. Article ; Online: Synthesis, Structural Studies and Molecular Modelling of a Novel Imidazoline Derivative with Antifungal Activity

    Tomasz M. Wróbel / Urszula Kosikowska / Agnieszka A. Kaczor / Sylwia Andrzejczuk / Zbigniew Karczmarzyk / Waldemar Wysocki / Zofia Urbańczyk-Lipkowska / Maja Morawiak / Dariusz Matosiuk

    Molecules, Vol 20, Iss 8, Pp 14761-

    2015  Volume 14776

    Abstract: Six novel imidazoline derivatives were synthesized and tested in antifungal assays. One of the compounds, N-cyclohexyl-2-imino-3-(4-nitrophenyl)imidazolidine-1-carboxamide showed moderate activity against several clinical strains of Candida albicans. Its ...

    Abstract Six novel imidazoline derivatives were synthesized and tested in antifungal assays. One of the compounds, N-cyclohexyl-2-imino-3-(4-nitrophenyl)imidazolidine-1-carboxamide showed moderate activity against several clinical strains of Candida albicans. Its structure was solved by X-ray crystallography and its mode of action was deduced using molecular modelling. It was found to be similar to that of fluconazole. The potential for further optimization including SAR of the compound is briefly discussed.
    Keywords antifungal ; Candida albicans ; X-ray analysis ; 14-α-sterol demethylase ; molecular modelling ; synthesis ; Organic chemistry ; QD241-441
    Language English
    Publishing date 2015-08-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    Full text online

    More links

    Kategorien

    Inter-library loan at ZB MED

    Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

To top