Laura Popa
ACS - Cercetari Arctice și Antarctice
Biografie
Efectuez atât cercetare fundamentală, cât și aplicată, specializându-mă în caracterizarea bacteriilor. Aceasta implică studierea izolatelor clinice și a tulpinilor bacteriene din mediile acvatice. Folosesc tehnici de microbiologie, cum ar fi cultivarea, selecția, conservarea, teste fenotipice și genotipice și experimente de conjugare. Sunt expert în tehnologiile de secvențiere de generația a doua (HiSeq, MiSeq, NovaSeq Illumina, Ion Torrent) și de generația a treia (MinION, Oxford Nanopore Technologies). Pentru analiza datelor, am experiență cu instrumente și platforme bioinformatice, inclusiv Geneious, ABRicate, SPAdes, CGE (ResFinder, PathogenFinder, VirulenceFinder, MLST, PlasmidFinder, MGE, CARD), BLAST NCBI și Clustal Omega, concentrându-mă pe rezistența la antibiotice și pe agenții patogeni ESKAPE.
Publicatii
Publication | Authors | Date | |
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article
Green Extraction Techniques Of Phytochemicals From Hedera Helix L. And In Vitro Characterization Of The Extracts |
Gavrila Adina I.; Zalaru Christina M.; Tatia Rodica; Seciu-Grama Ana-Maria; Negrea Cristina L.; Calinescu Ioan; Chipurici Petre; Trifan Adrian; Popa Ioana | Plants-Basel, 2023 | |
RezumatHedera helix L. contains phytochemicals with good biological properties which are beneficial to human health and can be used to protect plants against different diseases. The aim of this research was to find the most suitable extraction method and the most favorable parameters for the extraction of different bioactive compounds from ivy leaves. Different extraction methods, namely microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and conventional heating extraction (CHE), were used. The most suitable method for the extraction of saponins is MAE with an extraction efficiency of 58%, while for carbohydrates and polyphenols, the best results were achieved via UAE with an extraction efficiency of 61.7% and 63.5%, respectively. The antioxidant activity (AA) of the extracts was also determined. The highest AA was obtained via UAE (368.98 +/- 9.01 mu mol TR/gDM). Better results were achieved at 50( degrees)C for 10 min of extraction, using 80% ethanol in water as solvent. In order to evaluate their in vitro cytotoxicity, the extracts richest in bioactive compounds were tested on NCTC fibroblasts. Their influence on the DNA content of RAW 264.7 murine macrophages was also tested. Until 200 mu g/mL, the extracts obtained via UAE and MAE were cytocompatible with NCTC fibroblasts at 48 h of treatment. Summarizing the above, both MAE and UAE can be employed as green and efficient methods for producing extracts rich in bioactive compounds, exhibiting strong antioxidant properties and good noncytotoxic activity. |
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conference
Identification And Measurments Of Organochlorine Compounds In Danube Delta |
C. Itcus; C. Coman; L. Popa. D. Florea; M. Sidoroff; I. Tusa | The 7Th International Conference Ecological And Environmental Chemistry, Chisinau, Republic Of Moldova, 2022 | |
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article
Ultrasound Assisted Extraction Of Saponins From Hedera Helix L. And An In Vitro Biocompatibility Evaluation Of The Extracts |
Gavrila Adina I; Tatia Rodica; Seciu-Grama Ana-Maria; Tarcomnicu Isabela; Negrea Cristina; Calinescu Ioan; Zalaru Christina; Moldovan Lucia; Raiciu Anca D.; Popa Ioana | Pharmaceuticals, 2022 | |
RezumatThe aim of this study was to establish the best ultrasound assisted extraction (UAE) conditions of saponins from Hedera helix L. leaves and to evaluate the in vitro biocompatibility of the extracts richest in saponins. Different parameters, such as extraction time, temperature, ultrasound power, solvent to plant material ratio, and solvent concentration, were investigated. The most efficient extraction conditions were a temperature of 50 degrees C, an ultrasound amplitude of 40%, an extraction time of 60 min, a plant material to solvent ratio of 1:20 (w:v), and 80% ethanol as solvent. In vitro cytotoxicity of the extracts richest in saponins and their influence on the DNA content of L929 (NCTC) fibroblasts were tested. Until 200 mu g/mL, the studied extracts were cytocompatible with L929 fibroblast cell lines at 48 h of treatment. These in vitro cell culture results provide useful information for further applications of Hedera helix extracts in a pharmaceutical field. |
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article
Network Analytics For Drug Repurposing In Covid-19 |
Siminea Nicoleta; Popescu Victor; Martin Jose Angel Sanchez; Florea Daniela; Gavril Georgiana; Gheorghe Ana-Maria; Itcus Corina; Kanhaiya Krishna; Pacioglu Octavian; Popa Laura Lona; Trandafir Romica; Tusa Maria Iris; Sidoroff Manuela; Paun Mihaela; Czeizler Eugen; Paun Andrei; Petre Ion | Briefings In Bioinformatics, 2022 | |
RezumatTo better understand the potential of drug repurposing in COVID-19, we analyzed control strategies over essential host factors for SARS-CoV-2 infection. We constructed comprehensive directed protein-protein interaction (PPI) networks integrating the top-ranked host factors, the drug target proteins and directed PPI data. We analyzed the networks to identify drug targets and combinations thereof that offer efficient control over the host factors. We validated our findings against clinical studies data and bioinformatics studies. Our method offers a new insight into the molecular details of the disease and into potentially new therapy targets for it. Our approach for drug repurposing is significant beyond COVID-19 and may be applied also to other diseases. |
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article
Temporo-Spatial Variations In Resistance Determinants And Clonality Of Acinetobacter Baumannii And Pseudomonas Aeruginosa Strains From Romanian Hospitals And Wastewaters |
Gheorghe-Barbu Irina; Barbu Ilda Czobor; Popa Laura Ioana; Pircalabioru Gratiela Gradisteanu; Popa Marcela; Marutescu Luminita; Nita-Lazar Mihai; Banciu Alina; Stoica Catalina; Gheorghe Stefania; Lucaciu Irina; Sandulescu Oana; Paraschiv Simona; Surleac Marius; Talapan Daniela; Muntean Andrei Alexandru; Preda Madalina; Muntean Madalina-Maria; Dragomirescu Cristiana Cerasella; Popa Mircea Ioan; Otelea Dan; Chifiriuc Mariana Carmen | Antimicrobial Resistance And Infection Control, 2022 | |
RezumatBackground: Romania is one of the European countries reporting very high antimicrobial resistance (AMR) rates and consumption of antimicrobials. We aimed to characterize the AMR profiles and clonality of 304 multi-drug resistant (MDR) Acinetobacter baumannii (Ab) and Pseudomonas aeruginosa (Pa) strains isolated during two consecutive years (2018 and 2019) from hospital settings, hospital collecting sewage tanks and the receiving wastewater treatment plants (WWTPs) located in the main geographical regions of Romania. Methods: The strains were isolated on chromogenic media and identified by MALDI-TOF-MS. Antibiotic susceptibility testing and confirmation of ESBL- and CP- producing phenotypes and genotypes were performed. The genetic characterization also included horizontal gene transfer experiments, whole-genome sequencing (WGS), assembling, annotation and characterization. Results: Both clinical and aquatic isolates exhibited high MDR rates, especially the Ab strains isolated from nosocomial infections and hospital effluents. The phenotypic resistance profiles and MDR rates have largely varied by sampling point and geographic location. The highest MDR rates in the aquatic isolates were recorded in Galati WWTP, followed by Bucharest. The Ab strains harbored mostly bla(OX)(A-)(23), bla(OXA-)(24), bla(SHV), bla(TEM) and bla(GES), while Pa strains bla(IMP), bla(VIM), bla(NDM), bla(V)(EB), bla(GES) and bla(TEM), with high variations depending on the geographical zone and the sampling point. The WGS analysis revealed the presence of antibiotic resistance genes (ARGs) to other antibiotic classes, such as aminoglycosides, tetracyclines, sulphonamides, fosfomycin, phenicols, trimethoprim-sulfamethoxazole as well as class 1 integrons. The molecular analyses highlighted: (i) The presence of epidemic clones such as ST2 for Ab and ST233 and ST357 for Pa; (ii) The relatedness between clinical and hospital wastewater strains and (iii) The possible dissemination of clinical Ab belonging to ST2 (also proved in the conjugation assays for bla(OX)(A-)(23) or bla(OX)(A-)(72) genes), ST79 and ST492 and of Pa strains belonging to ST357, ST640 and ST621 in the wastewaters. Conclusion: Our study reveals the presence of CP-producing Ab and Pa in all sampling points and the clonal dissemination of clinical Ab ST2 strains in the wastewaters. The prevalent clones were correlated with the presence of class 1 integrons, suggesting that these isolates could be a significant reservoir of ARGs, being able to persist in the environment. |
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conference
Persitența Unei Clone Klebsiella Pneumoniae St101 Multi-Rezistente Din Mediul Clinic În Influentul Și Ef-Luentul Spitalului După Clorinare |
Popa L.I; Gheorghe I.; Czobor Barbu I.; Surleac M.; Paraschiv S.; Marutescu L.; Popa M.; Pircalabioru G.;et al. | Conferinţa Ştiinţifică De Primăvară A Aosr - On-Line Sub Genericul „Academia Oamenilor De Ştiinţă Din România –Personalităţi, Realizări, Obiective”, Bucuresti, Romania, 2021 | |
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conference
Aspecte Privind Epide-Miologia Moleculară A Rezistenței La Antibiotice Beta-Lactamice De Ultimă Generație În Mediul Clinic Și Acvatic |
Popa L.I.; Surleac M.; Muntean A.; Dragomirescu C.; Popa M.I.; Chifiriuc C. | Sesiunea Științifică Anuală, Simpozion Omagial Cu Titlul Institutul „Cantacuzino”, 100 De Ani În Slujba Sănătății, 2021 | |
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conference
Network Controllability Analysis For Drug Repurposing In Covid-19 |
Nicoleta Siminea; Victor Popescu; Jose Angel Sanchez Martin; Ana-Maria Dobre; Daniela Florea; Geor-giana Gavril; Corina Ițcuș; Krishna Kanhaiya; Octavian Pacioglu; Laura Ioana Popa; Romica Trandafir; Maria Iris Tușa; Manuela Sidoroff; Mihaela Păun; Eugen Czeizler; Andrei Păun; Ion Petre | The 29Th Conference On Inteligent Systems For Molecular Biology, Joint With The 20Th European Conference On Computational Biology, 2021 | |
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conference
Tracking Down Multidrug-Resistant Acinetobacter Baumannii Isolates From Hospital To The Aquat-Ic Environment Via The Wastewater Network |
Gheorghe I.; Barbu I. *; Surleac M.; Popa L.; Paraschiv S.; Popa M.; Grădișteanu G.; Măruțescu L.; Talapan D.; Banciu A.; Stoica C; Gheorghe S; Irina L.; Nita Lazar M.; Muntean A.; Otelea D.; Popa M.I.; Chifiriuc M.C.; 2021 | 31St European Congress Of Clinical Microbiology & Infectious Diseases, Vienna, Austria, 2021 | |
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article
Phenotypic And Genotypic Virulence Features Of Staphylococcal Strains Isolated From Difficult-To-Treat Skin And Soft Tissue Infections |
Preda Madalina; Mihai Mara Madalina; Popa Laura Ioana; Ditu Lia-Mara; Holban Alina Maria; Manolescu Loredana Sabina Cornelia; Popa Gabriela-Loredana; Muntean Andrei-Alexandru; Gheorghe Irina; Chifiriuc Carmen Mariana; Popa Mircea-Ioan | Plos One, 2021 | |
RezumatChronic infections represent an important burden on the healthcare system and have a significant impact on the patients' quality of life. While Staphylococcus spp. are commensal bacteria, they can become pathogenic, leading to various types of infections. In this study we aimed to characterize the virulence profiles of staphylococcal strains involved in difficult-to-treat skin and soft tissue infections, from both phenotypic and genotypic points of view. Phenotypic ability of the strains to secrete soluble virulence factors was assessed by a culturing dependent assay and their capacity to develop biofilms on inert substrate was screened by an adapted crystal violet microtiter method. We also tested the presence of several virulence genes by PCR. Most of the studied strains were isolated from purulent secretions of acne lesions and frequently secreted two or three soluble virulence factors. Most frequently secreted soluble virulence factors were caseinase (89%), lipase (71%) and lecithinase (67%). Almost half of the strains produced a well-represented biofilm. The molecular characterization showed the presence of the genes cna, hlg, clfA, and clfB. Staphylococcal strains that produce difficult-to-treat skin and soft tissue infections seem to be characterized by an enhanced ability to produce different soluble virulence factors and to develop biofilms in vitro. Further studies need to be developed in other Staphylococcus spp. infections in order to confirm this hypothesis. |
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article
Multidrug Resistant Klebsiella Pneumoniae St101 Clone Survival Chain From Inpatients To Hospital Effluent After Chlorine Treatment |
Popa Laura Ioana; Gheorghe Irina; Barbu Ilda Czobor; Surleac Marius; Paraschiv Simona; Marutescu Luminita; Popa Marcela; Pircalabioru Gratiela Gradisteanu; Talapan Daniela; Nita Mihai; Streinu-Cercel Anca; Streinu-Cercel Adrian; Otelea Dan; Chifiriuc Mariana Carmen | Frontiers In Microbiology, 2021 | |
RezumatIn this paper we describe the transmission of a multi-drug resistant Klebsiella pneumoniae ST101 clone from hospital to wastewater and its persistence after chlorine treatment. Water samples from influents and effluents of the sewage tank of an infectious diseases hospital and clinical strains collected from the intra-hospital infections, during a period of 10 days prior to wastewater sampling were analyzed. Antibiotic resistant K. pneumoniae strains from wastewaters were recovered on selective media. Based on antibiotic susceptibility profiles and PCR analyses of antibiotic resistance (AR) genetic background, as well as whole-genome sequencing (Illumina MiSeq) and subsequent bioinformatic analyses, 11 ST101 K. pneumoniae strains isolated from hospital wastewater influent, wastewater effluent and clinical sector were identified as clonally related. The SNP and core genome analyses pointed out that five strains were found to be closely related (with <= 18 SNPs and identical cgMLST profile). The strains belonging to this clone harbored multiple acquired AR genes [bla(CTX-M-)(15), bla(OXA-)(48), bla(OXA-)(1), bla(SHV-)(106), bla(TEM-)(150), aac(3)-IIa, aac(6 ')-Ib-cr, oqxA10, oqxB17, fosA, catB3, dfrA14, tet(D)] and chromosomal mutations involved in AR (Delta mgrB, Delta ompK35, amino acid substitutions in GyrA Ser83Tyr, Asp87Asn, ParC Ser80Tyr). Twenty-nine virulence genes involved in iron acquisition, biofilm and pili formation, adherence, and the type six secretion system - T6SS-III were identified. Our study proves the transmission of MDR K. pneumoniae from hospital to the hospital effluent and its persistence after the chlorine treatment, raising the risk of surface water contamination and further dissemination to different components of the trophic chain, including humans. |
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article
Subtypes, Resistance And Virulence Platforms In Extended-Drug Resistant Acinetobacter Baumannii Romanian Isolates |
Gheorghe I.; Barbu I.C.; Surleac M.; Sârbu I.; Popa L.I.; Paraschiv S.; Feng Y.; Lazăr V.; Chifiriuc M.C.; Oţelea D.; Zhiyong Z. | Scientific Reports, 2021 | |
RezumatAcinetobacter baumannii has emerged worldwide as a dominant pathogen in a broad range of severe infections, raising an acute need for efficient antibacterials. This is the first report on the resistome and virulome of 33 extended drug-resistant and carbapenem-resistant A. baumannii (XDR CRAB) strains isolated from hospitalized and ambulatory patients in Bucharest, Romania. A total of 33 isolates were collected and analyzed using phenotypic antibiotic susceptibility and conjugation assays, PCR, whole-genome sequencing (WGS), pulsed-field gel electrophoresis (PFGE) and MultiLocus Sequence Typing (MLST). All isolates were extensively drug-resistant (XDR), being susceptible only to colistin. The carbapenem resistance was attributed by PCR mainly to blaOXA-24 and blaOXA-23 genes. PFGE followed by MLST analysis demonstrated the presence of nine pulsotypes and six sequence types. WGS of seven XDR CRAB isolates from healthcare-associated infections demonstrated the high diversity of resistance genes repertoire, as well as of mobile genetic elements, carrying ARGs for aminoglycosides, sulphonamides and macrolides. Our data will facilitate the understanding of resistance, virulence and transmission features of XDR AB isolates from Romanian patients and might be able to contribute to the implementation of appropriate infection control measures and to develop new molecules with innovative mechanisms of action, able to fight effectively against these bugs, for limiting the spread and decreasing the infection rate and mortality. © 2021, The Author(s). |
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article
Targeting Plasmids To Limit Acquisition And Transmission Of Antimicrobial Resistance |
Vrancianu Corneliu Ovidiu; Popa Laura Ioana; Bleotu Coralia; Chifiriuc Mariana Carmen | Frontiers In Microbiology, 2020 | |
RezumatAntimicrobial resistance (AMR) is a significant global threat to both public health and the environment. The emergence and expansion of AMR is sustained by the enormous diversity and mobility of antimicrobial resistance genes (ARGs). Different mechanisms of horizontal gene transfer (HGT), including conjugation, transduction, and transformation, have facilitated the accumulation and dissemination of ARGs in Gram-negative and Gram-positive bacteria. This has resulted in the development of multidrug resistance in some bacteria. The most clinically significant ARGs are usually located on different mobile genetic elements (MGEs) that can move intracellularly (between the bacterial chromosome and plasmids) or intercellularly (within the same species or between different species or genera). Resistance plasmids play a central role both in HGT and as support elements for other MGEs, in which ARGs are assembled by transposition and recombination mechanisms. Considering the crucial role of MGEs in the acquisition and transmission of ARGs, a potential strategy to control AMR is to eliminate MGEs. This review discusses current progress on the development of chemical and biological approaches for the elimination of ARG carriers. |
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article
Dna Origami Design And Implementation: The Romanian Map |
Popa Laura Ioana; Dobre Ana-Maria; Itcus Corina; Amarioarei Alexandru; Paun Andrei; Paun Mihaela; Pop Felician; Tusa Iris; Minh-Kha Nguyen; Kuzyk Anton; Czeizler Eugen | Romanian Biotechnological Letters, 2020 | |
RezumatSince its introduction in the early 2000s, DNA origami had a big impact on the development of nanotechnology by gathering numerous applications. During this time, many tools were designed and used to generate arbitrary shapes capable of self-assembly which make this technique more approachable. In this paper, we have created the map of Romania at nanoscale dimensions by using a new open-source software - PERDIX. For this purpose, we used a scaffold strand with a length of 6959 nucleotides and 162 staple strands with a variable length ranging between 20 and 63 nucleotides. All the computational tools that were used in this experiment are open-source and user-friendly. |
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article
Whole Genome Sequencing Snapshot Of Multi-Drug Resistant Klebsiella Pneumoniae Strains From Hospitals And Receiving Wastewater Treatment Plants In Southern Romania |
Surleac Marius; Barbu Ilda Czobor; Paraschiv Simona; Popa Laura Ioana; Gheorghe Irina; Marutescu Luminita; Popa Marcela; Sarbu Ionela; Talapan Daniela; Nita Mihai; Iancu Alina Viorica; Arbune Manuela; Manole Alina; Nicolescu Serban; Sandulescu Oana; Streinu-Cercel Adrian; Otelea Dan; Chifiriuc Mariana Carmen | Plos One, 2020 | |
RezumatWe report on the genomic characterization of 47 multi-drug resistant, carbapenem resistant and ESBL-producing K. pneumoniae isolates from the influent (I) and effluent (E) of three wastewater treatment plants (WWTPs) and from Romanian hospital units which are discharging the wastewater in the sampled WWTPs. The K. pneumoniae whole genome sequences were analyzed for antibiotic resistance genes (ARGs), virulence genes and sequence types (STs) in order to compare their distribution in C, I and E samples. Both clinical and environmental samples harbored prevalent and widely distributed ESBL genes, i.e. blaSHV, bla(OXA), bla(TEM) and bla(CTX M). The most prevalent carbapenemase genes were bla(NDM-1), bla(OXA-48) and bla(KPC-2). They were found in all types of isolates, while bla(OXA-162), a rare blaOXA-48 variant, was found exclusively in water samples. A higher diversity of carbapenemases genes was seen in wastewater isolates. The aminoglycoside modifying enzymes (AME) genes found in all types of samples were aac(6'), ant(2'')Ia, aph(3'), aaD, aac(3) and aph(6). Quinolone resistance gene qnrS1 and the multi-drug resistance oqxA/B pump gene were found in all samples, while qnrD and qnrB were associated to aquatic isolates. The antiseptics resistance gene qacEdelta1 was found in all samples, while qacE was detected exclusively in the clinical ones. Trimethroprim-sulfamethoxazole (dfrA, sul1 and sul2), tetracyclines (tetA and tetD) and fosfomycin (fosA6, known to be located on a transpozon) resistance genes were found in all samples, while for choramphenicol and macrolides some ARGs were detected in all samples (catA1 and catB3 / mphA), while other (catA2, cmIA5 and aac(6')Ib / mphE and msrE) only in wastewater samples. The rifampin resistance genes arr2 and 3 (both carried by class I integrons) were detected only in water samples. The highly prevalent ARGs preferentially associating with aquatic versus clinical samples could ascribe potential markers for the aquatic (blaSHV-145, qacEdelta1, sul1, aadA1, aadA2) and clinical (bla(OXA-1), bla(SHV-106),bla(TEM-150), aac(3)Iia, dfrA14, oqxA10; oqxB17,catB3, tetD) reservoirs of AR. Moreover, some ARGs (oqxA10; blaSHV-145; blaSHV-100, aac(6')Il, aph(3') VI, armA, arr2, cmlA5, blaCMY-4, mphE, msrE, oqxB13, blaOXA-10) showing decreased prevalence in influent versus effluent wastewater samples could be used as markers for the efficiency of the WWTPs in eliminating AR bacteria and ARGs. The highest number of virulence genes (75) was recorded for the I samples, while for E and C samples it was reduced to half. The most prevalent belong to three functional groups: adherence (fim genes), iron acquisition (ent, fep, fyu, irp and ybt genes) and the secretion system (omp genes). However, none of the genes associated with hypervirulent K. pneumoniae have been found. A total of 14 STs were identified. The most prevalent clones were ST101, ST219 in clinical samples and ST258, ST395 in aquatic isolates. These STs were also the most frequently associated with integrons. ST45 and ST485 were exclusively associated with I samples, ST11, ST35, ST364 with E and ST1564 with C samples. The less frequent ST17 and ST307 aquatic isolates harbored blaOXA-162, which was co-expressed in our strains with bla(CTX-M-15) and bla(OXA-1). |
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article
Whole Genome Sequencing Snapshot Of Multidrug Resistant Klebsiella Pneumoniae Strains From Hospitals And Receiving Wastewater Treatment Plants In Southern Romania |
Surleac M.; Barbu I.C.; Paraschiv S.; Popa L.I.; Gheorghe I.; Marutescu L.; Popa M.; Sarbu I.; Talapan D.; Nita M.; Iancu A.V.; Arbune M.; Manole A.; Nicolescu S.; Sandulescu O.; Streinu-Cercel A.; Otelea D.; Chifiriuc M.C. | Plos One, 2020 | |
RezumatWe report on the genomic characterization of 47 multi-drug resistant, carbapenem resistant and ESBL-producing K. pneumoniae isolates from the influent (I) and effluent (E) of three wastewater treatment plants (WWTPs) and from Romanian hospital units which are discharging the wastewater in the sampled WWTPs. The K. pneumoniae whole genome sequences were analyzed for antibiotic resistance genes (ARGs), virulence genes and sequence types (STs) in order to compare their distribution in C, I and E samples. Both clinical and environmental samples harbored prevalent and widely distributed ESBL genes, i.e. blaSHV, blaOXA, blaTEM and blaCTX M. The most prevalent carbapenemase genes were blaNDM-1, blaOXA-48 and blaKPC-2. They were found in all types of isolates, while blaOXA-162, a rare blaOXA-48 variant, was found exclusively in water samples. A higher diversity of carbapenemases genes was seen in wastewater isolates. The aminoglycoside modifying enzymes (AME) genes found in all types of samples were aac(6’), ant(2’’)Ia, aph(3’), aaD, aac(3) and aph(6). Quinolone resistance gene qnrS1 and the multi-drug resistance oqxA/B pump gene were found in all samples, while qnrD and qnrB were associated to aquatic isolates. The antiseptics resistance gene qacEdelta1 was found in all samples, while qacE was detected exclusively in the clinical ones. Trimethroprim-sulfamethoxazole (dfrA, sul1 and sul2), tetracyclines (tetA and tetD) and fosfomycin (fosA6, known to be located on a transpozon) resistance genes were found in all samples, while for choramphenicol and macrolides some ARGs were detected in all samples (catA1 and catB3 / mphA), while other (catA2, cmIA5 and aac(6’)Ib / mphE and msrE) only in wastewater samples. The rifampin resistance genes arr2 and 3 (both carried by class I integrons) were detected only in water samples. The highly prevalent ARGs preferentially associating with aquatic versus clinical samples could ascribe potential markers for the aquatic (blaSHV-145, qacEdelta1, sul1, aadA1, aadA2) and clinical (blaOXA-1, blaSHV-106,blaTEM-150, aac(3)Iia, dfrA14, oqxA10; oqxB17,catB3, tetD) reservoirs of AR. Moreover, some ARGs (oqxA10; blaSHV-145; blaSHV-100, aac(6’)Il, aph(3’) VI, armA, arr2, cmlA5, blaCMY-4, mphE, msrE, oqxB13, blaOXA-10) showing decreased prevalence in influent versus effluent wastewater samples could be used as markers for the efficiency of the WWTPs in eliminating AR bacteria and ARGs. The highest number of virulence genes (75) was recorded for the I samples, while for E and C samples it was reduced to half. The most prevalent belong to three functional groups: adherence (fim genes), iron acquisition (ent, fep, fyu, irp and ybt genes) and the secretion system (omp genes). However, none of the genes associated with hypervirulent K. pneumoniae have been found. A total of 14 STs were identified. The most prevalent clones were ST101, ST219 in clinical samples and ST258, ST395 in aquatic isolates. These STs were also the most frequently associated with integrons. ST45 and ST485 were exclusively associated with I samples, ST11, ST35, ST364 with E and ST1564 with C samples. The less frequent ST17 and ST307 aquatic isolates harbored blaOXA-162, which was co-expressed in our strains with blaCTX-M-15 and blaOXA-1. © 2020 Surleac et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
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article
Histo-Anatomic Aspects On Zea Mays L. Influenced By Spruce Bark Polyphenolic Extract |
Tanase Corneliu; Boz Irina; Popa Valentin I. | Romanian Biotechnological Letters, 2016 | |
RezumatThe paper present histo-anatomic aspects, recorded in seedlings of maize (Zea mays L.) grown under the influence of spruce bark polyphenolic extract (SBPE). Spruce barck polyphenolic extract was characterized in terms of the total content of polyphenols, tannins, flavonols, flavonoids and anthocyanins in a previous paper. It is known that, natural polyphenols are essential compounds in stimulating plant growth and development. The aim of this study was to identify the internal structure changes in maize seedlings, under the influence of SBPE, applied in two concentrations (SB1 - 190 mg GAE / L and SB2 - 130 mg GAE / L). It was observed, compared with the control, that SBPE determines a better development of the absorbents bristle and increase leading bundles number and central vessels metaxylem. SBPE in lower concentrations has positive effects that can be attributed to antioxidant properties. The results recorded in this study open new pathways of research in the field. |
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article
Eucalyptus-Collagen Composite Gels For Dentistry Applications |
Rusu L. C.; Kaya D. A.; Ghica M. V.; Albu M. G.; Popa L.; Butu A.; Dinu-Pirvu C. E. | Digest Journal Of Nanomaterials And Biostructures, 2014 | |
RezumatComposite gels based on collagen and eucalyptus oil were prepared in order to be used in dentistry. The main components such as beta-Cymene (32.1%), Eucalyptol (36.59%), Cryptone (4.35%) and Spathulenol (3.82%) of Eucalyptus camadulensis Dehnh. essential oil were determined by GC-MS. The eucalyptus oil dissolved in different concentration of ethanol (4 and 8% v/v) was embedded in collagen gels (0.4 and 0.8% w/w) and crosslinked with tannic acid (0.2 and 0.4% w/w). The stability of gels was depending on collagen concentration, only the gels with 0.8% of collagen being stable. The rheological analysis of composite gels showed that formulation containing a combination of ethanol and tannic acid at the ratio of 8% v/v: 0.4% w/w resulted in the highest consistency index and yield stress. All the 0.8% collagen gels exhibited a suitable pseudoplastic behaviour and could be recommended for an adequate administration in the oral cavity. |