Hadiye Demirbakan

Dr. Hadiye Demirbakan

orcid

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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21 May 2021 in Journal of Medical Virology
Verified
Journal Article
Open access
PDF file
ABAysen Bayram
Aysen Bayram
HDHadiye Demirbakan
Hadiye Demirbakan
PKPınar Günel Karadeniz
Pınar Günel Karadeniz
MEMerve Erdoğan
Merve Erdoğan
IKIpek Koçer
Ipek Koçer
Quantitation of antibodies to the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) was performed for the detection of adaptive immune response in healthcare workers (HCWs) vaccinated with CorovaVac. We prospectively recruited HCWs from a university hospital in Turkey. Serum samples from 1072 HCWs were obtained following 28 days of the first, and 21 days of the second dose. Detection and quantitation of SARS‐CoV‐2 antispike antibodies were performed by the chemiluminescent microparticle immunoassay (SARS‐CoV‐2 IgG II Quant; Abbott). Results greater than or equal to the cutoff value 50.0 AU/ml were reported as positive. After the first dose, antispike antibodies were detected in 834 of 1072 (77.8%) HCWs. Seropositivity was higher among females (84.6%) than males (70.6%) (p < 0.001) and was found to be highest in both women and men between the ages of 18–34. After the second dose, antibodies were detected in 1008 of 1012 (99.6%) HCWs. Antibody titers were significantly higher in those who had coronavirus disease‐2019 before vaccination than those who did not (p < 0.001). Antibody positivity and median antibody titers were significantly less in HCWs with chronic diseases compared to those without (p < 0.05 and p < 0.001, respectively). In conclusion, our findings indicated that a relatively high frequency (99.6%) of humoral immunity was produced in HCWs aged 18–59 after two doses of CoronaVac. Quantitation of antibodies may help facilitate longitudinal monitoring of the antibody response, which will be especially useful in deciding the dose of the vaccine in vulnerable groups such as those over 60 years of age and those with chronic diseases.

6 February 2026 in Microorganisms
Verified
Journal Article
Open access
PDF file
GEGULFEM ECE
GULFEM ECE
AAAhmet Aktaş
Ahmet Aktaş
ÖÖÖzlem Koyuncu Özyurt
Özlem Koyuncu Özyurt
HDHadiye Demirbakan
Hadiye Demirbakan
HAHikmet Eda Alışkan
Hikmet Eda Alışkan
TATuğba Kula Atik
Tuğba Kula Atik
The human microbiome is increasingly recognized as a key determinant of health and disease, yet methodological variability continues to limit reproducibility and clinical translation of findings. This review synthesizes current approaches in microbiome research, critically evaluating each step from sampling to sequencing and downstream bioinformatics. Pre-analytical factors such as sample type, collection method, preservation, and storage conditions profoundly affect microbial community profiles and remain a major source of bias. Nucleic acid extraction protocols and quality assessment strategies are discussed with emphasis on optimized lysis techniques, contamination controls, and DNA yield evaluation. Advances in sequencing technologies are highlighted, including 16S rRNA amplicon sequencing, shotgun metagenomics, third-generation long-read platforms, and emerging single-cell and minimal-input methods, each with specific advantages and limitations in taxonomic and functional resolution. Bioinformatics pipelines for taxonomic profiling, variant detection, phylogenetic inference, and functional annotation are compared, with attention to widely used reference databases such as RefSeq, GTDB, and SILVA. Integrative multi-omics approaches, including metatranscriptomics, metabolomics, and genome-scale metabolic modeling, are presented as powerful tools for linking microbial community structure to host physiology and disease mechanisms. Despite these advances, the lack of standardized workflows across pre-analytical, sequencing, and computational steps continues to hinder inter-study comparability and biomarker validation. This review aims to provide a methodological framework that highlights both strengths and limitations of current technologies while underlining the need for harmonized protocols to ensure reproducibility and accelerate the translation of microbiome research into clinical practice.

1 February 2025 in Microorganisms
Verified
Journal Article
Open access
PDF file
GEGULFEM ECE
GULFEM ECE
AAAhmet Aktaş
Ahmet Aktaş
ACAyse Caner
Ayse Caner
ISIMRAN SAGLIK
IMRAN SAGLIK
TATuğba Kula Atik
Tuğba Kula Atik
OZOrçun Zorbozan
Orçun Zorbozan
The human microbiome, which encompasses microbial communities and their genetic material, significantly influences health and disease, including cancer. The urogenital microbiota, naturally present in the urinary and genital tracts, interact with factors such as age, lifestyle, and health conditions to affect homeostasis and carcinogenesis. Studies suggest that alterations in this microbiota contribute to the development and progression of genitourinary cancers, emphasizing the concept of oncobiome, which refers to microbial genetic contributions to cancer. Similarly, gut microbiota can influence hormone levels and systemic inflammation, impacting cancers such as cervical and prostate cancer. Advanced studies indicate that microbial communities in genitourinary cancers have distinct profiles that may serve as diagnostic biomarkers or therapeutic targets. Dysbiosis of the urinary microbiota correlates with bladder and kidney cancer. Additionally, gut microbiota influence the effectiveness of cancer treatments. However, further research is necessary to clarify causality, the role of microbial metabolites, and hormonal regulation. The aim of this review is to understand that these dynamics present opportunities for innovative cancer diagnostics and therapies, highlighting the need for integration of microbiology, oncology, and genomics to explore the role of microbiota in genitourinary cancers. For this, a comprehensive search of relevant databases was conducted, applying specific inclusion and exclusion criteria to identify studies examining the association between microbiota and urogenital cancers. Research into the mechanisms by which microbiota influence urogenital cancers may pave the way for new diagnostic and therapeutic approaches, ultimately improving patient outcomes.

1 January 2021 in International Journal of Hyperthermia
Verified
Journal Article
Open access
DGDeniz Gazel
Deniz Gazel
HDHadiye Demirbakan
Hadiye Demirbakan
MEMehmet Erinmez
Mehmet Erinmez
Swarming motility is a virulence factor for Proteus mirabilis and is a coordinated multicellular movement of bacteria. In this study, we investigated the inhibitory effect of hyperthermia on bacterial swarming motility and antimicrobial resistance. Thirty-one P. mirabilis isolates were included in the study. Seven inoculated agar plates were incubated inside incubators with increasing temperature levels: at 36 °C (control) and 40–45 °C. On the next day, inhibition of swarming was evaluated and minimum paralyzing temperature (MPT) values were determined. An antimicrobial susceptibility test (antibiogram) is performed by exposing bacteria to increasing concentrations of antibiotics, in vitro. Thus, we used the Kirby-Bauer disk diffusion test as a screening method to analyze the antibiogram profiles of the isolates at 36 °C and 42 °C. Finally, a time-kill assay was performed to analyze the killing effect of hyperthermia (42 °C) on planktonic bacteria, in combination with the antibiotic meropenem at the first and third hours. A Wilcoxon signed-rank test was used to compare the killing effects of meropenem, hyperthermia and their combinations. The median MPT value was determined as 44 °C. In the disk diffusion assay, susceptibility development was observed in 94% of isolates for at least one antibiotic. In the time-kill assay, we observed a significant killing effect of hyperthermia in combination with meropenem. Under the microscope, we observed the formation of spherical cells by the effect of heat. We conclude that these findings might be useful when employing the hyperthermia method to treat infectious diseases caused by P. mirabilis in the future.

10 October 2025 in Medicine
Verified
Journal Article
Open access
IKipek koçer
ipek koçer
HDHadiye Demirbakan
Hadiye Demirbakan
Background: Carbapenem-resistant Klebsiella pneumoniae (CRKp) is an urgent global health threat due to its rapid spread and limited treatment options. Ceftazidime–avibactam exhibits broad efficacy against gram-negative bacteria, including CRKp; however, emerging resistance to this agent is increasingly reported. Understanding the prevalence of ceftazidime–avibactam resistance and the underlying carbapenemase genes is critical for optimizing antimicrobial stewardship and guiding clinical management. This study aimed to determine the prevalence of ceftazidime avibactam resistance among CRKp isolates collected from various clinical specimens, and to analyze their associated carbapenemase genes and antibiotic resistance profiles. Methods: This cross-sectional study analyzed 312 K pneumoniae isolates obtained from various clinical specimens of hospitalized patients at a tertiary care hospital in Turkey. Antibiotic susceptibility testing was performed using the disk diffusion method for ceftazidime–avibactam and broth microdilution for both colistin and ceftazidime–avibactam. Molecular detection of carbapenemase genes was carried out using polymerase chain reaction. Results: Ceftazidime–avibactam resistance was identified in 21.5% (67/312) of CRKp isolates. Among these isolates, 37.3% harbored both OXA-48 and NDM genes, 13.4% carried NDM alone, 10.4% carried OXA-48 alone, and 38.8% lacked these genes. The majority of resistant isolates originated from urine (31.3%), followed by tracheal aspirate (29.9%), and blood (22.4%) specimens. The prevalence of colistin susceptibility among ceftazidime–avibactam-resistant CRKp isolates was 56.7%. Conclusions: The coexistence of NDM and OXA-48 genes is a major contributor to ceftazidime–avibactam resistance in CRKp isolates, particularly in urinary and respiratory tract infections. These findings underscore the need for ongoing surveillance and tailored antibiotic stewardship programs to control the spread of resistance in hospital settings.

8 December 2022 in Turkish Journal of Pediatric Emergency and Intensive Care Medicine
Verified
Journal Article
Closed access
HDHadiye Demirbakan
Hadiye Demirbakan
IKİpEk Koçer
İpEk Koçer
YSYusuf Ünal Sarıkabadayı
Yusuf Ünal Sarıkabadayı