berna ozer

Mrs. berna ozer

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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21 January 2020 in Emerging Microbes & Infections
Verified
Journal Article
Open access
CVCansel vatansever
Cansel vatansever
SMSirin Menekse
Sirin Menekse
ODOzlem Dogan
Ozlem Dogan
LGLal Sude Gucer
Lal Sude Gucer
BOberna ozer
berna ozer
FCFüsun Can
Füsun Can
Here, we presented 11 cases with colistin-resistant Pseudomonas aeruginosa infection and co-existence of OXA-48 and NDM-1 in the ST235 high-risk clone. The molecular analyses were performed by Sanger sequencing and RT–PCR. The eight patients (72.7%) had an invasive infection and three (27.3%) had colonization. The 30-day mortality rate was 87.5% (7/8). Three patients (37.5%, 3/8) received colistin therapy before isolation of P. aeruginosa. In the Multilocus sequence typing (MLST) analysis of 11 isolates, eight (72.7%) isolates belonged to P. aeruginosa ST235 clone. All isolates were NDM-1 positive, and nine isolates (81.8%) were found to be positive for both OXA-48 and NDM-1. Sequences of pmrAB and phoPQ revealed numerous insertions and deletions in all isolates. In 10 isolates pmrAB and phoPQ were found to be upregulated. In conclusion, the co-existence of OXA-48 and NDM-1 genes in colistin-resistant P. aeruginosa ST235 high-risk clone indicates the spread of carbapenemases in clinical isolates and highlights need of continuous surveillance for high-risk clones of P. aeruginosa.

25 April 2023 in Cells
Verified
Journal Article
Open access
PDF file
ETEvangelia Thanou
Evangelia Thanou
FKFrank Koopmans
Frank Koopmans
DPDébora Pita-Illobre
Débora Pita-Illobre
RKRemco Klaassen
Remco Klaassen
BOberna ozer
berna ozer
Ka Wan LiKa Wan Li
Ka Wan Li
Suspension TRAPping filter (sTRAP) is an attractive sample preparation method for proteomics studies. The sTRAP protocol uses 5% SDS that maximizes protein solubilization. Proteins are trapped on a borosilicate glass membrane filter, where SDS is subsequently removed from the filter. After trypsin digestion, peptides are analyzed directly by LC-MS. Here, we demonstrated the use of a low-cost plasmid DNA micro-spin column for the sTRAP sample preparation of a dilution series of a synapse-enriched sample with a range of 10–0.3 µg. With 120 ng tryptic peptides loaded onto the Evosep LC system coupled to timsTOF Pro 2 mass spectrometer, we identified 5700 protein groups with 4% coefficient of variation (CoV). Comparing other sample preparation protocols, such as the in-gel digestion and the commercial Protifi S-TRAP with the plasmid DNA micro-spin column, the last is superior in both protein and peptide identification numbers and CoV. We applied sTRAP for the analysis of the hippocampal proteome from the 5xFAD mouse model of Alzheimer’s disease and their wildtype littermates, and revealed 121 up- and 54 down-regulated proteins. Protein changes in the mutant mice point to the alteration of processes related to the immune system and Amyloid aggregation, which correlates well with the known major Alzheimer’s-disease-related pathology. Data are available via ProteomeXchange with the identifier PXD041045.

27 July 2022 in Advanced Science
Verified
Journal Article
Open access
AKAlisan Kayabolen
Alisan Kayabolen
UAUgur Akcan
Ugur Akcan
DÖDoğancan Özturan
Doğancan Özturan
HPHivda Ulbegi Polat
Hivda Ulbegi Polat
GSGizem Nur Sahin
Gizem Nur Sahin
TBTugba Bagci-Onder
Tugba Bagci-Onder
Soluble ACE2 (sACE2) decoys are promising agents to inhibit SARS‐CoV‐2, as their efficiency is unlikely to be affected by escape mutations. However, their success is limited by their relatively poor potency. To address this challenge, multimeric sACE2 consisting of SunTag or MoonTag systems is developed. These systems are extremely effective in neutralizing SARS‐CoV‐2 in pseudoviral systems and in clinical isolates, perform better than the dimeric or trimeric sACE2, and exhibit greater than 100‐fold neutralization efficiency, compared to monomeric sACE2. SunTag or MoonTag fused to a more potent sACE2 (v1) achieves a sub‐nanomolar IC50, comparable with clinical monoclonal antibodies. Pseudoviruses bearing mutations for variants of concern, including delta and omicron, are also neutralized efficiently with multimeric sACE2. Finally, therapeutic treatment of sACE2(v1)‐MoonTag provides protection against SARS‐CoV‐2 infection in an in vivo mouse model. Therefore, highly potent multimeric sACE2 may offer a promising treatment approach against SARS‐CoV‐2 infections.

1 January 2021 in Bratislava Medical Journal
Verified
Journal Article
Open access
OCO. Catal
O. Catal
BOberna ozer
berna ozer
MSM. Sit
M. Sit
Management of patients with colorectal cancer in COVID-19 pandemic hospital

6 January 2021 in bioRxiv
Verified
Preprint
Open access
PDF file
AKAlisan Kayabolen
Alisan Kayabolen
UAUgur Akcan
Ugur Akcan
DODogancan Ozturan
Dogancan Ozturan
HPHivda Ulbegi Polat
Hivda Ulbegi Polat
GSGizem Nur Sahin
Gizem Nur Sahin
TBTugba Bagci-Onder
Tugba Bagci-Onder
Soluble ACE2 (sACE2) decoy receptors are promising agents to inhibit SARS-CoV-2, as their efficiency is less likely to be affected by common escape mutations in viral proteins. However, their success may be limited by their relatively poor potency. To address this challenge, we developed a large decoy library of sACE2 fusion proteins, generated with several protease inhibitors or multimerization tags. Among these decoys, multimeric sACE2 consisting of SunTag or MoonTag systems, which were originally utilized for signal amplification or gene activation systems, were extremely effective in neutralizing SARS-CoV-2 in pseudoviral systems and in clinical isolates. These novel sACE2 fusion proteins exhibited greater than 100-fold SARS-CoV-2 neutralization efficiency, compared to monomeric sACE2. SunTag or MoonTag in combination with a more potent version of sACE2, which has multiple point mutations for greater binding (v1), achieved near complete neutralization at a sub-nanomolar range, comparable with clinical monoclonal antibodies. Pseudoviruses bearing mutant versions of Spike, alpha, beta, gamma or delta variants, were also neutralized efficiently with SunTag or MoonTag fused sACE2(v1). Finally, therapeutic treatment of sACE2(v1)-MoonTag provided protection against SARS-CoV-2 infection in an in vivo mouse model. Overall, we suggest that the superior activity of the sACE2-SunTag or sACE2-MoonTag fusions is due to the greater occupancy of the multimeric sACE2 receptors on Spike protein as compared to monomeric sACE2. Therefore, these highly potent multimeric sACE2 decoy receptors may offer a promising treatment approach against SARS-CoV-2 infections. One Sentence Summary: Multimerization of sACE2 markedly enhanced the neutralization of SARS-CoV-2 by blocking multiple viral spike proteins simultaneously.

31 August 2021 in Infectious Diseases and Clinical Microbiology
Verified
Journal Article
Closed access
ODOzlem Dogan
Ozlem Dogan
HAHacer Aktürk
Hacer Aktürk
BOberna ozer
berna ozer
ENElif NURTOP
Elif NURTOP
CVCansel vatansever
Cansel vatansever
Onder ErgonulOnder Ergonul
Onder Ergonul
The clinical findings of SARS-CoV-2 infection are heterogeneous, and the duration of viral RNA shedding varies on the age of the patient, severity of the disease, and type of the sample. For that reason, a comprehensive analysis of the dynamics of viral shedding is critical for (...)