scholarly journals MICROBIOLOGICAL FEATURES OF STAPHYLOCOCCUS AUREUS ISOLATED FROM RESPIRATORY TRACT OF CHILDREN WITH CYSTIC FIBROSIS

2021 ◽  
Vol 74 (9) ◽  
pp. 2094-2099
Author(s):  
Oksana Ishchenko ◽  
Iryna Koshova ◽  
Inna Borysova ◽  
Dmytro Stepanskyi
Keyword(s):  
Cystic Fibrosis ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Prevalence Rate ◽  
Posterior Pharyngeal Wall ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Pharyngeal Wall ◽  
Small Colony Variants ◽  
Small Colony

The aim: To determine the prevalence rate of Staphylococcus aureus infection among children with Cystic Fibrosis in the Dnieper region, to provide microbiological characteristics of the isolates and to elevate their susceptibility to antimicrobials. Materials and methods: Sputum, tracheobronchial lavage waters and/ or deep smear from the posterior pharyngeal wall were taken from children with genetically confirmed Cystic Fibrosis. Bacteriological method was the main. The first screening for small colony variants of Staphylococcus aureus was carried out after 48 hours of incubation. The antimicrobials susceptibility testing was determined by disk-diffusion method according to the EUCAST 2019. Microsoft Office Excel 2010 was used for statistical data processing. Results: Twenty one children were enrolled in the survey. The culture of Staphylococcus spp. was obtained from all patients with 40.8% positive for Staphylococcus aureus. Small colony variants appeared with the prevalence rate 21.6% after 48 hours of incubation. The frequency of associations between Staphylococcus aureus with auxotroph phenotype with the presence of Pseudomonas aeruginosa was significantly higher than with wild-type group. The 3d-generation aminoglycosides, the 3d-generation fluoroquinolones, linezolid, rifampicin and tetracyclines showed the best antimicrobial activity, however, resistance to cefoxitin and gentamicin was significantly higher in auxotroph-modified group. Conclusions: Infection Staphylococcus aureus is common among children. The appearance of auxotrophs registered after treatment with aminoglycosides and/ or co-trimoxazole and co-infection Pseudomonas aeruginosa. Isolates of Staphylococcus aureus showed good chemotherapeutic sensitivity, but tendency in increasing resistance registered for auxotroph-modified phenotype.

scholarly journals Microbiological features of Pseudomonas aeruginosa in children with Cystic Fibrosis

2021 ◽  
Vol 26 (3) ◽  
pp. 131-138
Author(s):  
O.V. Ishchenko ◽  
D.O. Stepanskyi
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Agents ◽  
Posterior Pharyngeal Wall ◽  
Biochemical Properties ◽  
Diffusion Method ◽  
Candida Spp ◽  
Disk Diffusion Method ◽  
Pharyngeal Wall ◽  
Main Research

The purpose of the study was to determine the frequency rate of Pseudomonas aeruginosa infection among children with cystic fibrosis (CF) in Dnipro region and to provide microbiological characteristics of the obtained isolates. The study was conducting from January 2019 to December 2020. Children with genetically confirmed CF diagnosis were enrolled. The main research method was bacteriological with identification of microorganisms by biochemical properties; antimicrobial susceptibility was determined by disk-diffusion method. Biological material: mucus from a deep smear from the posterior pharyngeal wall, sputum and tracheobronchial lavage waters. The Leeds criteria were used to define persons with chronic infection. The study involved 21 children. We collected 183 respiratory samples with 49 isolates of P. aeruginosa. The most important co-existing pathogens were Staphylococcus aureus, Aspergillus spp. and Candida spp. In our study, P. aeruginosa was associated with Aspergillus spp. (χ2=20.952; df=1; p˂0.001). Mucoid isolates were found in 24.49% of cases. P. aeruginosa showed variable sensitivity to different groups of antimicrobial agents, but the highest resistance was to penicillins. Mucoid P. aeruginosa was more resistant to penicillins (p˂0.001) and cephalosporins (p=0.036). Infection P. aeruginosa is frequent among children with CF; there were three children with chronic bronchopulmonary infection P. aeruginosa in Dnipro region in the end of 2020. The likelihood of Aspergillus spp. infection was higher in the case of current P. aeruginosa infection. P. aeruginosa showed variable susceptibility to different groups of antimicrobial agents, but mucoid isolates were more resistant.

scholarly journals Antimicrobial Activity of Cultivable Endophytic and Rhizosphere Fungi Associated with “Mile-a-Minute,” Mikania cordata (Asteraceae)

2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Pavithra L. Jayatilake ◽  
Helani Munasinghe
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Antimicrobial Properties ◽  
Pharmaceutical Products ◽  
Diffusion Method ◽  
Molecular Characteristics ◽  
Disk Diffusion Method ◽  
Rhizosphere Fungi

Endophytic and rhizosphere fungi are understood to be aiding the host plant to overcome a range of biotic and abiotic stresses (nutrition depletion, droughts, etc.) hence, they remain to be reservoirs of plethora of natural products with immense use. Consequently, this investigation of endophytic and rhizosphere fungi isolated from Mikania cordata (a perennial vine that is well established in Sri Lanka) for their antimicrobial properties was performed with the aim of future derivation of potential beneficial pharmaceutical products. Leaves, twigs, and roots of M. cordata were utilized to isolate a total of 9 endophytic fungi out of which the highest amount (44%) accounted was from the twigs. A sample of the immediate layer of soil adhering to the root of M. cordata was utilized to isolate 15 rhizosphere fungi. Fusarium equiseti and Phoma medicaginis were endophytes that were identified based on colony and molecular characteristics. The broad spectrum of antimicrobial activity depicted by F. equiseti (MK517551) was found to be significantly greater (p≤0.05, inhibitory against Bacillus cereus ATCC 11778, Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) than P. medicaginis (MK517550) (inhibitory against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa ATCC 25853) as assessed using the Kirby-Bauer disk diffusion method. Trichoderma virens and Trichoderma asperellum were rhizospere fungi that exhibited remarkable antimicrobial properties against the test pathogens chosen for the study. T. asperellum indicated significantly greater bioactivity against all four bacterial pathogens and Candida albicans ATCC 10231 under study. The ranges of minimum inhibitory concentrations (MICs) of the fungi depicting antimicrobial properties were determined. The results obtained suggest that F. equiseti, P. medicaginis, T. asperellum, and T. virens of M. cordata harness bioprospective values as natural drug candidates. This is the first report on isolation and evaluation of the antimicrobial properties of endophytic and rhizosphere fungi of Mikania cordata.

scholarly journals Pseudomonas aeruginosa Rugose Small-Colony Variants Have Adaptations That Likely Promote Persistence in the Cystic Fibrosis Lung

2009 ◽  
Vol 191 (11) ◽  
pp. 3492-3503 ◽  
Author(s):  
Melissa Starkey ◽  
Jason H. Hickman ◽  
Luyan Ma ◽  
Niu Zhang ◽  
Susan De Long ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Pseudomonas Aeruginosa ◽  
Intracellular Signaling ◽  
Tricarboxylic Acid Cycle ◽  
Gene Clusters ◽  
Wild Type ◽  
Phenotypic Analysis ◽  
Small Colony Variants ◽  
Airway Infections ◽  
Small Colony

ABSTRACT Pseudomonas aeruginosa is recognized for its ability to colonize diverse habitats, ranging from soil to immunocompromised people. The formation of surface-associated communities called biofilms is one factor thought to enhance colonization and persistence in these diverse environments. Another factor is the ability of P. aeruginosa to diversify genetically, generating phenotypically distinct subpopulations. One manifestation of diversification is the appearance of colony morphology variants on solid medium. Both laboratory biofilm growth and chronic cystic fibrosis (CF) airway infections produce rugose small-colony variants (RSCVs) characterized by wrinkled, small colonies and an elevated capacity to form biofilms. Previous reports vary on the characteristics attributable to RSCVs. Here we report a detailed comparison of clonally related wild-type and RSCV strains isolated from both CF sputum and laboratory biofilm cultures. The clinical RSCV had many characteristics in common with biofilm RSCVs. Transcriptional profiling and Biolog phenotypic analysis revealed that RSCVs display increased expression of the pel and psl polysaccharide gene clusters, decreased expression of motility functions, and a defect in growth on some amino acid and tricarboxylic acid cycle intermediates as sole carbon sources. RSCVs also elicited a reduced chemokine response from polarized airway epithelium cells compared to wild-type strains. A common feature of all RSCVs analyzed in this study is increased levels of the intracellular signaling molecule cyclic di-GMP (c-di-GMP). To assess the global transcriptional effects of elevated c-di-GMP levels, we engineered an RSCV strain that had elevated c-di-GMP levels but did not autoaggregate. Our results showed that about 50 genes are differentially expressed in response to elevated intracellular c-di-GMP levels. Among these genes are the pel and psl genes, which are upregulated, and flagellum and pilus genes, which are downregulated. RSCV traits such as increased exopolysaccharide production leading to antibiotic tolerance, altered metabolism, and reduced immunogenicity may contribute to increased persistence in biofilms and in the airways of CF lungs.

scholarly journals UJI AKTIVITAS ANTIBAKTERI EKSTRAK ETANOL RIMPANG KUNYIT (Curcuma longa L.) TERHADAP Staphylococcus aureus DAN Pseudomonas aeruginosa

2019 ◽  
Vol 4 (1) ◽  
pp. 278-287
Author(s):  
Lia Fikayuniar ◽  
Neni Sri Gunarti ◽  
Mellya Apriliani
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antibacterial Activity ◽  
Curcuma Longa ◽  
Ethanol Extract ◽  
Inhibition Zone ◽  
Negative Control ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Paper Disk

ABSTRAK Kunyit (Curcuma longa L.) merupakan salah satu jenis tanaman obat yang termasuk dalam keluarga Zingiberaceae. Senyawa aktif yang terkandung dalam rimpang kunyit (Curcuma longa L.) mampu bekerja sebagai antibakteri. Penelitian ini bertujuan untuk mengetahui aktivitas antibakteri dari ekstrak etanol rimpang kunyit (Curcuma longa L.) terhadap Staphylococcus aureus dan Pseudomonas aeruginosa. Ekstraksi dilakukan dengan cara refluks menggunakan pelarut etanol 96%. Pengujian aktivitas antibakteri dilakukan menggunakan metode difusi paper disk dengan masing-masing konsentrasi ekstrak 10%, 20%, 30%, 40% b/v. Kontrol positif yang digunakan adalah Ciprofloxacin sedangkan kontrol negatif yang digunakan adalah DMSO. Hasil skrining fitokimia ekstrak etanol rimpang kunyit mengandung alkaloid, flavonoid, fenol, tanin dan terpenoid. Berdasarkan hasil penelitian, ekstrak etanol rimpang kunyit dapat menghambat bakteri Staphylococcus aureus dan Pseudomonas aeruginosa pada konsentrasi 10%, 20%, 30%, 40% dan konsentrasi 40% merupakan konsentrasi yang memberikan diameter zona hambat terbesar terhadap kedua bakteri uji yaitu 8,63 mm dan 7,8 mm. Kata Kunci : aktivitas antibakteri, Curcuma longa L., Staphylococcus aureus,    ABSTRACT Turmeric (Curcuma longa L.) is one type of medicinal plant that belongs to the Zingiberaceae family. The active compounds contained in the Curcuma longa L. rhizome can work as antibacterial. This study aims to determine the antibacterial activity of the ethanol extract of Curcuma longa L. Antibacterial activity testing was carried out using the paper disk diffusion method with each extract concentration of 10%, 20%, 30%, 40%. The positive control used was Ciprofloxacin while the negative control used was DMSO. The results of phytochemical screening of the ethanol extract of Curcuma longa L. rhizome contain alkaloids, flavonoids, phenols, tannins and terpenoids. Based on the results of the study, the ethanol extract of turmeric rhizome can inhibit Staphylococcus aureus and Pseudomonas aeruginosa bacteria at concentrations of 10%, 20%, 30%, 40% and 40% concentrations which give the largest inhibition zone diameter of the two test bacteria which is 8.63 mm and 7.8 mm. Keywords: antibacterial activity, Curcuma longa L., Staphylococcus aureus,  

scholarly journals Tomatidine Inhibits Replication of Staphylococcus aureus Small-Colony Variants in Cystic Fibrosis Airway Epithelial Cells

2011 ◽  
Vol 55 (5) ◽  
pp. 1937-1945 ◽  
Author(s):  
Gabriel Mitchell ◽  
Mariza Gattuso ◽  
Gilles Grondin ◽  
Éric Marsault ◽  
Kamal Bouarab ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Staphylococcus Aureus ◽  
Electron Transport ◽  
Epithelial Cells ◽  
Airway Epithelial Cells ◽  
Plant Secondary Metabolite ◽  
Airway Epithelial ◽  
Small Colony Variants ◽  
Content Type ◽  
Small Colony

ABSTRACTSmall-colony variants (SCVs) often are associated with chronicStaphylococcus aureusinfections, such as those encountered by cystic fibrosis (CF) patients. We report here that tomatidine, the aglycon form of the plant secondary metabolite tomatine, has a potent growth inhibitory activity against SCVs (MIC of 0.12 μg/ml), whereas the growth of normalS. aureusstrains was not significantly altered by tomatidine (MIC, >16 μg/ml). The specific action of tomatidine was bacteriostatic for SCVs and was clearly associated with their dysfunctional electron transport system, as the presence of the electron transport inhibitor 4-hydroxy-2-heptylquinoline-N-oxide (HQNO) caused normalS. aureusstrains to become susceptible to tomatidine. Inversely, the complementation of SCVs' respiratory deficiency conferred resistance to tomatidine. Tomatidine provoked a general reduction of macromolecular biosynthesis but more specifically affected the incorporation of radiolabeled leucine in proteins of HQNO-treatedS. aureusat a concentration corresponding to the MIC against SCVs. Furthermore, tomatidine inhibited the intracellular replication of a clinical SCV in polarized CF-like epithelial cells. Our results suggest that tomatidine eventually will find some use in combination therapy with other traditional antibiotics to eliminate persistent forms ofS. aureus.

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