Oana Mariana Cristea

Dr. Oana Mariana Cristea

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Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 April 2022 in Antibiotics
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Journal Article
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Alice Elena GheneaAlice Elena Ghenea
Alice Elena Ghenea
OZOvidiu Mircea Zlatian
Ovidiu Mircea Zlatian
OCOana Mariana Cristea
Oana Mariana Cristea
AUAnca Ungureanu
Anca Ungureanu
Radu-Razvan MititeluRadu-Razvan Mititelu
Radu-Razvan Mititelu
MBMaria Balasoiu
Maria Balasoiu
Background: CTX-M betalactamases have shown a rapid spread in the recent years among Enterobacteriaceae and have become the most prevalent Extended Spectrum Beta-Lactamases (ESBLs) in many parts of the world. The introduction and dissemination of antibiotic-resistant genes limits options for treatment, increases mortality and morbidity in patients, and leads to longer hospitalization and expensive costs. We aimed to identify the beta-lactamases circulating encoded by the genes blaCTX-M-15, blaSHV-1 and blaTEM-1 in Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae) strains. Furthermore, we established the associated resistance phenotypes among patients hospitalized in the Intensive Care Unit (ICU) from County Clinical Emergency Hospital of Craiova, Romania. Methods: A total of 46 non-duplicated bacterial strains (14 strains of E. coli and 32 strains of K. pneumoniae), which were resistant to ceftazidime (CAZ) and cefotaxime (CTX) by Kirby–Bauer disk diffusion method, were identified using the automated VITEK2 system. Detection of ESBL-encoding genes and other resistance genes was carried out by PCR. Results. E. coli strains were resistant to 3rd generation cephalosporins and moderately resistant to quinolones, whereas K. pneumoniae strains were resistant to penicillins, cephalosporins, and sulfamides, and moderately resistant to quinolones and carbapenems. Most E. coli strains harbored blaCTX-M-15 gene (13/14 strains), a single strain had the blaSHV-1 gene, but 11 strains harbored blaTEM-1 gene. The mcr-1 gene was not detected. We detected tet(A) gene in six strains and tet(B) in one strain. In K. pneumoniae strains we detected blaCTX-M-15 in 23 strains, blaSHV-1 in all strains and blaTEM-1 in 14 strains. The colistin resistance gene mcr-1 was not detected. The tetracycline gene tet(A) was detected in 11 strains, but the gene tet(B) was not detected in any strains. Conclusions. The development in antibiotic resistance highlights the importance of establishing policies to reduce antibiotic use and improving the national resistance surveillance system in order to create local antibiotic therapy guidelines.

17 October 2022 in Infection and Drug Resistance
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AGAndreea Loredana Golli
Andreea Loredana Golli
OCOana Mariana Cristea
Oana Mariana Cristea
OZOvidiu Zlatian
Ovidiu Zlatian
AGAdina-Dorina Glodeanu
Adina-Dorina Glodeanu
ABAndrei Theodor Balasoiu
Andrei Theodor Balasoiu
SPSimona Georgiana Popa
Simona Georgiana Popa
Introduction: Bloodstream infections are the most severe infections that cause the highest mortality rate, especially in patients admitted to the intensive care unit (ICU). In this study, we aimed to analyze the distribution, resistance patterns and prevalence of MDR (multidrug-resistant) pathogens isolated in blood samples collected from patients with severe invasive infections hospitalized in the ICU. Methods: A retrospective study of bacterial pathogens was performed on 490 patients admitted to the ICU between 2017 and 2020. The resistance patterns were analyzed using Vitek 2 Compact system. Results: In total, 617 bacterial isolates were obtained. Four hundred and twenty-seven isolates (69.21%) were Gram positive and 190 isolates (30.79%) were Gram negative bacteria. The most frequently isolated micro-organisms identified in the blood samples for the entire period (2017– 2020) were Coagulase-negative staphylococci (CoNS) (318– 51.54%), followed by Klebsiella pneumoniae (70– 11.34%), Methicillin-Resistant Staphylococcus aureus (MRSA) (58– 9.40%), Acinetobacter baumannii (45– 7.29%) and Enterococcus faecalis (42– 6.80%). The number of Klebsiella pneumoniae strains significantly increased in 2020, compared to the previous year (p < 0.05). The Acinetobacter baumannii prevalence was significantly higher in the age group of 20– 64 years (10.89%) and over 65 years (3.53%) (p < 0.001). The difference between the prevalence of CoNS in the elderly (67.84%) and in adults (20– 64 years) (52.47%) was also statistically significant (p < 0.001). High rates of MDR were found for Acinetobacter baumannii (97.77%), Pseudomonas aeruginosa (65%), Klebsiella pneumoniae (50%), Enterococcus faecalis (47.61%) and MRSA (46.55%). More than 60% of the Klebsiella pneumoniae strains were found to be resistant to carbapenems. Conclusion: The study revealed an alarming prevalence of MDR strains isolated in blood samples of the patients admitted to the ICU, indicating the necessity of consistent application of the measures to control.

31 July 2017
Verified
Open access
OCOana Mariana Cristea
Oana Mariana Cristea
CACarmen Silvia Avrămescu
Carmen Silvia Avrămescu
MBMaria Bălășoiu
Maria Bălășoiu
FPF.D. Popescu
F.D. Popescu
FPFlorica Popescu
Florica Popescu
MAM.O. Amzoiu
M.O. Amzoiu
UTI with K. pneumoniae in patients with CKD is the second cause of urinary infection which raises problems of unfavorable evolution of CKD and also the recurrence of UTI with multiple drug resistance in CKD, which may lead to pharmacotherapeutical problems.

24 November 2023 in Biomedicines
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IPIoan Sabin Poenariu
Ioan Sabin Poenariu
BLBOLDEANU LIDIA
BOLDEANU LIDIA
Bogdan Silviu UngureanuBogdan Silviu Ungureanu
Bogdan Silviu Ungureanu
DCDaniel Cosmin Caragea
Daniel Cosmin Caragea
OCOana Mariana Cristea
Oana Mariana Cristea
Mihail Virgil BoldeanuMihail Virgil Boldeanu
Mihail Virgil Boldeanu
We intended to investigate the presence and medical application of serum hypoxia-inducible factor-1 alpha (HIF-1α) along with the already known systemic inflammatory markers and the new one’s inflammatory indices, the proportion of mean corpuscular volume and lymphocytes (MCVL) and the cumulative inflammatory index (IIC), for patients with ulcerative colitis (UC). We sought to establish correlations that may be present between the serum levels of HIF-1α and these inflammatory indices, as well as their relationship with disease activity and the extent of UC, which can provide us with a more precise understanding of the evolution, prognosis, and future well-being of patients. Serum samples were collected from 46 patients diagnosed with UC and 23 controls. For our assessment of the serum levels of HIF-1α, we used the Enzyme-Linked Immunosorbent Assay (ELISA) technique. Thus, for HIF-1α we detected significantly higher values in more severe and more extensive UC. When it came to MCVL and IIC, we observed statistically significant differences between the three groups being compared (Severe, Moderate, and Mild). Our study highlighted that HIF-1α correlated much better with a disease activity score, MCVL, and IIC. With MCVL and IIC, a strong and very strong correlation had formed between them and well-known inflammation indices. By examining the ROC curves of the analyzed parameters, we recognized that TWI (accuracy of 83.70%) provides the best discrimination of patients with early forms of UC, followed by HIF-1α (73.90% accuracy), MCVL (70.90% accuracy), and PLR (70.40%). In our study, we observed that HIF-1α, MCVL, and PLR had the same sensitivity (73.33%) but HIF-1α had a much better specificity (60.87% vs. 58.70%, and 54.35%). Also, in addition to the PLR, HIF-1α and MCVL can be used as independent predictor factors in the discrimination of patients with early forms of UC.

8 May 2023 in Diagnostics
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Mihail Virgil BoldeanuMihail Virgil Boldeanu
Mihail Virgil Boldeanu
BLBOLDEANU LIDIA
BOLDEANU LIDIA
OCOana Mariana Cristea
Oana Mariana Cristea
DCDana Alexandra Ciobanu
Dana Alexandra Ciobanu
IPIoan Sabin Poenariu
Ioan Sabin Poenariu
RIRazvan Ionescu
Razvan Ionescu
Identifying certain serum biomarkers associated with the degree of rheumatoid arthritis (RA) activity can provide us with a more accurate view of the evolution, prognosis, and future quality of life for these patients. Our aim was to analyze the presence and clinical use of matrix metalloproteinase-13 (MMP-13), along with vascular endothelial growth factor (VEGF) and well-known cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) for patients with RA. We also wanted to identify the possible correlations between MMP-13 and these serological markers, as well as their relationship with disease activity indices, quality of life, and ultrasonographic evaluation. For this purpose, we analyzed serum samples of 34 RA patients and 12 controls. In order to assess serum concentrations for MMP-13, VEGF, TNF-α, and IL-6, we used the enzyme-linked immunosorbent assay (ELISA) technique. Our results concluded that higher levels of MMP-13, VEGF, TNF-α, and IL-6 were present in the serum of RA patients compared to controls, with statistical significance. We furthermore identified moderately positive correlations between VEGF, MMP-13, and disease activity indices, as well as with the ultrasound findings. We also observed that VEGF had the best accuracy (97.80%), for differentiating patients with moderate disease activity. According to the data obtained in our study, that although MMP-13, TNF-α and C-reactive protein (CRP) have the same sensitivity (55.56%), MMP-13 has a better specificity (86.67%) in the diagnosis of patients with DAS28(4v) CRP values corresponding to moderate disease activity. Thus, MMP-13 can be used as a biomarker that can differentiate patients with moderate or low disease activity. VEGF and MMP-13 can be used as additional parameters, along with TNF-α and IL-6, that can provide the clinician a better picture of the inflammatory process, disease activity, and structural damage in patients with RA. Our data can certainly constitute a start point for future research and extended studies with multicenter involvement, to support the selection of individualized and accurate therapeutic management strategies for our patients.

1 January 2010
Verified
Journal Article
Closed access
CACarmen Avrămescu
Carmen Avrămescu
VBV Biciuşcă
V Biciuşcă
TDT Dăianu
T Dăianu
ATAdriana Turculeanu
Adriana Turculeanu
MBMaria Bălăşoiu
Maria Bălăşoiu
CSCristiana Eugenia Simionescu
Cristiana Eugenia Simionescu