Ivan Verdenik

Dr. Ivan Verdenik

Obstetrics & Gynecology, University Medical Center Ljubljana, Ljubljana, Slovenia
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Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

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

Representative Publications

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13 April 2014 in BioMed Research International
Verified
Journal Article
Open access
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SKSara Korosec
Sara Korosec
HFHelena Ban Frangež
Helena Ban Frangež
IVIvan Verdenik
Ivan Verdenik
UKUrska Kladnik
Urska Kladnik
VKVanja Kotar
Vanja Kotar
EBEda Vrtacnik Bokal
Eda Vrtacnik Bokal
The aim of the study was to compare the single pregnancy and neonate outcome after fresh and frozen-thawed embryo transfer in the in vitro fertilization programme (IVF). The study focused on clinical and laboratory factors affecting the abnormal placentation, especially placenta praevia, in patients conceiving in the IVF programme. The results confirm that neonates born after frozen-thawed embryo transfer had significantly higher mean birth weight than after fresh embryo transfer (ET). Moreover, the birth weight distribution in singletons was found to shift towards “large for gestation” (LGA) after frozen-thawed ET. On the other hand, the pregnancies after fresh ET were characterized by a higher incidence of placenta praevia and 3rd trimester bleeding. Placenta praevia was more common in IVF patients with fresh ET in a stimulated cycle than in patients with ET in a spontaneous cycle. It occurred more frequently in patients with transfer of 2 embryos. From this point of view, single ET and ET in a spontaneous cycle should be encouraged in good prognosis patients in the future with more than two good quality embryos developed. An important issue arose of how the ovarian hormonal stimulation relates to abnormal placentation and if the serum hormone levels interfere with in the IVF treatment results.

22 June 2021 in Healthcare
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NVNevenka Kregar Velikonja
Nevenka Kregar Velikonja
Beata DobrowolskaBeata Dobrowolska
Beata Dobrowolska
SSSanja Stanisavljević
Sanja Stanisavljević
Karmen ErjavecKarmen Erjavec
Karmen Erjavec
VVVislava Globevnik Velikonja
Vislava Globevnik Velikonja
IVIvan Verdenik
Ivan Verdenik
Several preventive measures have been applied to limit the COVID-19 pandemic, including successful the development and introduction of vaccines. The aim of this study was to investigate adherence to preventive measures and vaccination intentions among nursing students in three European countries and the factors associated with vaccination intention and advising vaccination. A cross-sectional study using convenience/snow-ball sampling strategy was performed in Slovenia, Poland, and Serbia between 12 February and 5 March 2021. Data from 872 eligible respondents were analyzed (mean age 23.5 ± 6.5 years, 89% female). Higher adherence to preventive behavior was declared by those working in healthcare (p < 0.001), engaged in COVID-19 departments (p < 0.001), had not had the disease yet (p < 0.001), and had children (p = 0.01). Those groups also expressed higher vaccination intention and advised vaccination to others. Higher vaccination intention and advising vaccination were mostly associated with belief in benefits of vaccine, trust in institutions, perceived effectiveness of vaccine, influence of social environment, protection of patients and perceived health care professionals’ duty. Fear of side effects and general refusal of vaccines are the main reasons for vaccination hesitancy. The results of the study indicate how higher education institutions can support the development of appropriate professional attitudes and behaviors among nursing students.

19 December 2020 in Journal of Clinical Medicine
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MHMarko Hojnik
Marko Hojnik
NŠNataša Kenda Šuster
Nataša Kenda Šuster
ŠSŠpela Smrkolj
Špela Smrkolj
SFSnježana Frkovič-Grazio
Snježana Frkovič-Grazio
IVIvan Verdenik
Ivan Verdenik
Tea Lanišnik RižnerTea Lanišnik Rižner
Tea Lanišnik Rižner
The aldo-keto reductase (AKR) superfamily is gaining attention in cancer research. AKRs are involved in important biochemical processes and have crucial roles in carcinogenesis and chemoresistance. The enzyme AKR1C3 has many functions, which include production of prostaglandins, androgens and estrogens, and metabolism of different chemotherapeutics; AKR1C3 is thus implicated in the pathophysiology of different cancers. Endometrial and ovarian cancers represent the majority of gynecological malignancies in developed countries. Personalized treatments for these cancers depend on identification of prognostic and predictive biomarkers that allow stratification of patients. In this study, we evaluated the immunohistochemical (IHC) staining of AKR1C3 in 123 paraffin-embedded samples of endometrial cancer and 99 samples of ovarian cancer, and examined possible correlations between expression of AKR1C3 and other clinicopathological data. The IHC expression of AKR1C3 was higher in endometrial cancer compared to ovarian cancer. In endometrioid endometrial carcinoma, high AKR1C3 IHC expression correlated with better overall survival (hazard ratio, 0.19; 95% confidence interval, 0.06−0.65, p = 0.008) and with disease-free survival (hazard ratio, 0.328; 95% confidence interval, 0.12–0.88, p = 0.027). In patients with ovarian cancer, there was no correlation between AKR1C3 IHC expression and overall and disease-free survival or response to chemotherapy. These results demonstrate that AKR1C3 is a potential prognostic biomarker for endometrioid endometrial cancer.

25 January 2018 in Journal of Occupational and Environmental Hygiene
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Journal Article
Closed access
ALAndreja Lang
Andreja Lang
Maja OvsenikMaja Ovsenik
Maja Ovsenik
IVIvan Verdenik
Ivan Verdenik
MRMaja Remškar
Maja Remškar
ČOČedomir Oblak
Čedomir Oblak
During material treatment in dentistry particles of different size are released in the air. To examine the degree of particle exposure, air scanning to dental employees was performed by the Scanning Mobility Particle Sizer. The size, shape and chemical composition of particles collected with a low-pressure impactor were determined by scanning electronic microscopy and X-ray dispersive analysis. The average concentrations of nanoparticles during working periods in a clean dental laboratory (45,000–56,000 particles/cm3), in an unclean dental laboratory (28,000–74,000 particles/cm3), and in a dental office (21,000–50,000 particles/cm3), were significantly higher compared to average concentrations during nonworking periods in the clean dental laboratory (11,000–24,000 particles/cm3), unclean laboratory (14,000–40,000 particles/cm3), and dental office (13,000–26,000 particles/cm3). Peak concentration of nanoparticles in work-intensive periods were found significantly higher (up to 773,000 particles/cm3), compared to the non-working periods (147,000 particles/cm3) and work-less intensive periods (365,000 particles/cm3). The highest mass concentration value ranged from 0.055–0.166 mg/m3. X-ray dispersive analysis confirmed the presence of carbon, potassium, oxygen, iron, aluminum, zinc, silicon, and phosphorus as integral elements of dental restorative materials in form of nanoparticle clusters, all smaller than 100 nm. We concluded that dental employees are exposed to nanoparticles in their working environment and are therefore potentially at risk for certain respiratory and systematic diseases.

5 February 2022 in Cancers
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MHMarko Hojnik
Marko Hojnik
NŠNataša Kenda Šuster
Nataša Kenda Šuster
ŠSŠpela Smrkolj
Špela Smrkolj
DSDamjan Sisinger
Damjan Sisinger
SFSnježana Frkovič-Grazio
Snježana Frkovič-Grazio
Tea Lanišnik RižnerTea Lanišnik Rižner
Tea Lanišnik Rižner
Although aldo-keto reductases (AKRs) have been widely studied in cancer, no study to date has examined the roles of AKR family 1 members B1 (AKR1B1) and B10 (AKR1B10) in a large group of ovarian cancer patients. AKR1B1 and AKR1B10 play a significant role in inflammation and the metabolism of different chemotherapeutics as well as cell differentiation, proliferation, and apoptosis. Due to these functions, we examined the potential of AKR1B1 and AKR1B10 as tissue biomarkers. We assessed the immunohistochemical levels of AKR1B1 and AKR1B10 in tissue paraffin sections from 99 patients with high-grade serous ovarian cancer (HGSC) and compared these levels with clinicopathological characteristics, survival, and response to chemotherapy. A higher immunohistochemical AKR1B1 expression correlated with a better overall and disease-free survival of HGSC patients whereas AKR1B10 expression did not show any significant differences. A multivariant Cox analysis demonstrated that a high AKR1B1 expression was an important prognostic factor for both overall and disease-free survival. However, AKR1B1 and AKR1B10 were not associated with different responses to chemotherapy. Our data suggest that AKR1B1 is involved in the pathogenesis of HGSC and is a potential prognostic biomarker for this cancer.

7 July 2021 in Cancers
Verified
Journal Article
Open access
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MHMarko Hojnik
Marko Hojnik
SFSnježana Frkovič-Grazio
Snježana Frkovič-Grazio
IVIvan Verdenik
Ivan Verdenik
Tea Lanišnik RižnerTea Lanišnik Rižner
Tea Lanišnik Rižner
The roles of aldo-keto reductase family 1 member B1 (AKR1B1) and B10 (AKR1B10) in the pathogenesis of many cancers have been widely reported but only briefly studied in endometrial cancer. To clarify the potential of AKR1B1 and AKR1B10 as tissue biomarkers of endometrial cancer, we evaluated the immunohistochemical levels of AKR1B1 and AKR1B10 in tissue paraffin sections from 101 well-characterized patients with endometrioid endometrial cancer and 12 patients with serous endometrial cancer and compared them with the clinicopathological data. Significantly higher immunohistochemical levels of AKR1B1 and AKR1B10 were found in adjacent non-neoplastic endometrial tissue compared to endometrioid endometrial cancer. A trend for better survival was observed in patients with higher immunohistochemical AKR1B1 and AKR1B10 levels. However, no statistically significant differences in overall survival or disease-free survival were observed when AKR1B1 or AKR1B10 were examined individually in endometrioid endometrial cancer. However, analysis of AKR1B1 and AKR1B10 together revealed significantly better overall and disease-free survival in patients with both AKR1B1 and AKR1B10 staining above the median values compared to all other patients. Multivariant Cox analysis identified strong AKR1B1 and AKR1B10 staining as a statistically important survival prediction factor. Conversely, no significant differences were found in serous endometrial cancer. Our results suggest that AKR1B1 and AKR1B10 play protective roles in endometrioid endometrial cancer and show potential as prognostic biomarkers.