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  1. Book ; Thesis: Structure function relationships of toll-like receptor 7 and 8 signalling

    Colak, Elif

    2012  

    Author's details presented by Elif Colak
    Language English
    Size XVI, 138 S., Ill., graph. Darst.
    Publishing country Germany
    Document type Book ; Thesis
    Thesis / German Habilitation thesis Heidelberg, Univ., Diss., 2012
    HBZ-ID HT017331967
    Database Catalogue ZB MED Medicine, Health

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  2. Article ; Online: Performance analysis of pretrained convolutional neural network models for ophthalmological disease classification.

    Emir, Busra / Colak, Ertugrul

    Arquivos brasileiros de oftalmologia

    2023  

    Abstract: Purpose: This study aimed to evaluate the classification performance of pretrained convolutional neural network models or architectures using fundus image dataset containing eight disease labels.: Methods: A publicly available ocular disease ... ...

    Abstract Purpose: This study aimed to evaluate the classification performance of pretrained convolutional neural network models or architectures using fundus image dataset containing eight disease labels.
    Methods: A publicly available ocular disease intelligent recognition database has been used for the diagnosis of eight diseases. This ocular disease intelligent recognition database has a total of 10,000 fundus images from both eyes of 5,000 patients for the following eight diseases: healthy, diabetic retinopathy, glaucoma, cataract, age-related macular degeneration, hypertension, myopia, and others. Ocular disease classification performances were investigated by constructing three pretrained convolutional neural network architectures including VGG16, Inceptionv3, and ResNet50 models with adaptive moment optimizer. These models were implemented in Google Colab, which made the task straight-forward without spending hours installing the environment and supporting libraries. To evaluate the effectiveness of the models, the dataset was divided into 70%, 10%, and 20% for training, validation, and testing, respectively. For each classification, the training images were augmented to 10,000 fundus images.
    Results: ResNet50 achieved an accuracy of 97.1%; sensitivity, 78.5%; specificity, 98.5%; and precision, 79.7%, and had the best area under the curve and final score to classify cataract (area under the curve = 0.964, final score = 0.903). By contrast, VGG16 achieved an accuracy of 96.2%; sensitivity, 56.9%; specificity, 99.2%; precision, 84.1%; area under the curve, 0.949; and final score, 0.857.
    Conclusions: These results demonstrate the ability of the pretrained convolutional neural network architectures to identify ophthalmological diseases from fundus images. ResNet50 can be a good architecture to solve problems in disease detection and classification of glaucoma, cataract, hypertension, and myopia; Inceptionv3 for age-related macular degeneration, and other disease; and VGG16 for normal and diabetic retinopathy.
    Language English
    Publishing date 2023-04-03
    Publishing country Brazil
    Document type Journal Article
    ZDB-ID 603915-7
    ISSN 1678-2925 ; 0004-2749
    ISSN (online) 1678-2925
    ISSN 0004-2749
    DOI 10.5935/0004-2749.2022-0124
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Using Thin Films of Phase-Change Material for Active Tuning of Terahertz Waves Scattering on Dielectric Cylinders.

    Cakmak, Atilla Ozgur / Colak, Evrim / Serebryannikov, Andriy E

    Materials (Basel, Switzerland)

    2024  Volume 17, Issue 1

    Abstract: The scattering of electromagnetic waves by isotropic dielectric cylinders can be dramatically modified by means of vanadium dioxide (VO2) thin-film coatings. Efficient dynamic control of scattering is achieved due to the variations in material parameters ...

    Abstract The scattering of electromagnetic waves by isotropic dielectric cylinders can be dramatically modified by means of vanadium dioxide (VO2) thin-film coatings. Efficient dynamic control of scattering is achieved due to the variations in material parameters realizable by means of external biasing. In this paper, we study the scattering of terahertz waves in a case where the coating shells are made of VO2, a phase-change material, whose thin films may work rather as electromagnetic phase screens in the insulator material phase, but as lossy quasi-metallic components in the metallic material phase. The shells that uniformly cover the dielectric cylinders are investigated. Attention will be paid to the demonstration of the potential of VO2 in the external control of diverse scattering regimes of the dielectric-VO2 core-shell scatterer, while conductivity of VO2 corresponds to rather insignificant variations in temperature. In line with the purposes of this work, it is shown that the different resonant and nonresonant regimes have different sensitivity to the variations in VO2 conductivity. Both the total scattering cross section and field distributions inside and around the core are studied, as well as the angle-dependent scattering cross section.
    Language English
    Publishing date 2024-01-04
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma17010260
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Multidetector Computed Tomographic Evaluation of the Normal Characteristics of the Thymus in the Pediatric Population.

    Çolak, Edis / Özkan, Behzat

    Journal of the Belgian Society of Radiology

    2022  Volume 106, Issue 1, Page(s) 110

    Abstract: Objectives: The objective of the present study was to determine the morphologic features and measurements of the normal thymus on contrast-enhanced multi-detector computed tomography (MDCT) in subjects from the newborn period up to 18 years of age.: ... ...

    Abstract Objectives: The objective of the present study was to determine the morphologic features and measurements of the normal thymus on contrast-enhanced multi-detector computed tomography (MDCT) in subjects from the newborn period up to 18 years of age.
    Materials and methods: The MDCT scans obtained from 464 children with a mean age ± SD of 8.43 ± 5.60 years were retrospectively re-evaluated. The shape, margins, side predominance, density, and measurements of the thymic gland were defined for each age group.
    Results: A triangular thymic shape with a middle location and straight lateral contours were the most frequently seen morphologic features in children. The mean anteroposterior and transverse diameter of the thymus was 17.32 ± 4.58 and 29.99 ± 11.42 mm, respectively. The mean values for the width and thickness were 20.66 ± 5.36 and 15.15 ± 6.76 mm for the right thymic lobe, respectively; and 26.14 ± 7.85 and 14.91 ± 5.51 mm for the left, respectively. The transverse diameter of the thymus and thymic lobe dimensions decreased significantly with age, however, the anteroposterior diameter of the thymus was not significantly associated with age. Girls had higher mean thymic attenuation values compared to boys, however, this gender difference was not statistically significant (63.8 ± 22.4 HU vs. 60.1 ± 25.3, p = 0.164).
    Conclusion: Our study provides a better understanding of the normal thymic appearances in children that can aid in accurate diagnosis and avoid unnecessary, costly, and invasive interventions.
    Language English
    Publishing date 2022-11-17
    Publishing country England
    Document type Journal Article
    ZDB-ID 2834839-4
    ISSN 2514-8281
    ISSN 2514-8281
    DOI 10.5334/jbsr.2971
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Characteristics and surgical outcomes of patients with atraumatic splenic rupture.

    Colak, Elif / Ciftci, Ahmet Burak

    The Journal of international medical research

    2022  Volume 50, Issue 2, Page(s) 3000605221080875

    Abstract: Objective: Although rare, late-diagnosed atraumatic splenic rupture (ASR) may result in mortality. We investigated the occurrence of ASR cases at our centre over the previous six years.: Methods: This was a retrospective, cross-sectional study that ... ...

    Abstract Objective: Although rare, late-diagnosed atraumatic splenic rupture (ASR) may result in mortality. We investigated the occurrence of ASR cases at our centre over the previous six years.
    Methods: This was a retrospective, cross-sectional study that included all patients who underwent emergency splenectomy due to ASR between January 01, 2015, and January 01, 2021.
    Results: Of the 203 patients who underwent splenectomy, 15 met our criteria for ASR. Median age was 55 years (34-90), and 10 (67%) patients were male. Most common pre-existing diseases were diabetes mellitus (6, 40%) and heart valve disease (5, 33%). Ten (67%) patients had splenic rupture due to splenic infarction and abscess. There were two (13%) cases with diffuse large B cell lymphoma (DLBCL) and two (13%) cases with lung cancer and spleen metastasis. Median length of hospital stay was 6 days (2-24) and three (20%) patients died in hospital.
    Conclusions: Male sex, previous splenic infarctions, haematological malignancies, lung cancer spleen metastases, underlying cardiovascular disease and diabetes mellitus may increase the risk for ASR. Further prospective controlled studies are needed to confirm our results.
    MeSH term(s) Cross-Sectional Studies ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Rupture, Spontaneous/surgery ; Splenic Rupture/surgery ; Treatment Outcome
    Language English
    Publishing date 2022-02-17
    Publishing country England
    Document type Journal Article
    ZDB-ID 184023-x
    ISSN 1473-2300 ; 0300-0605 ; 0142-2596
    ISSN (online) 1473-2300
    ISSN 0300-0605 ; 0142-2596
    DOI 10.1177/03000605221080875
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Acute Biliary Pancreatitis Management during the Coronavirus Disease 2019 Pandemic.

    Çolak, Elif / Çiftci, Ahmet Burak

    Healthcare (Basel, Switzerland)

    2022  Volume 10, Issue 7

    Abstract: 1) Objective: We aimed to analyze and describe the management of acute biliary pancreatitis (ABP) during the coronavirus disease 2019 (COVID-19) pandemic. (2) Methods: This was a retrospective cohort study among patients with ABP during a control period ...

    Abstract (1) Objective: We aimed to analyze and describe the management of acute biliary pancreatitis (ABP) during the coronavirus disease 2019 (COVID-19) pandemic. (2) Methods: This was a retrospective cohort study among patients with ABP during a control period (16 March 2019 to 15 March 2020; period 1) and a COVID-19 period (16 March 2020 to 15 March 2021; period 2). (3) Results: We included 89 patients with ABP, being 58 in period 1 and 31 in period 2. The mean patient age was 62.75 ± 16.59 years, and 51 (57.3%) patients were women. The Quick Sequential Organ Failure Assessment score for sepsis and World Society of Emergency Surgery Sepsis Severity Score were significantly higher among patients in period 2. Twenty-two patients (37.9%) in period 1 and six (19.3%) in period 2 underwent cholecystectomy. There were no significant differences in surgical interventions between the two periods. The hospital mortality rate was 3.4 and 19.3% in period 1 and period 2, respectively. Mortality was significantly higher in period 2. Conclusion: During the COVID-19 pandemic, we observed a significant reduction in the number of patients with ABP but increased severity and mortality. Multicenter studies with more patients are needed to obtain additional evidence regarding ABP management during the COVID-19 pandemic.
    Language English
    Publishing date 2022-07-11
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2721009-1
    ISSN 2227-9032
    ISSN 2227-9032
    DOI 10.3390/healthcare10071284
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Ultrasonographic measurements of the testicular volume in Turkish boys aged 0-8 years and comparison with international references.

    Çolak, Edis / Özkan, Behzat

    Journal of pediatric endocrinology & metabolism : JPEM

    2022  Volume 35, Issue 4, Page(s) 489–495

    Abstract: Objectives: Proper diagnosis and follow-up of children with testicular disorders depend on the presence of adequate references for testicular volume. The objective of this study was to determine the testicular volume by ultrasound in Turkish boys aged ... ...

    Abstract Objectives: Proper diagnosis and follow-up of children with testicular disorders depend on the presence of adequate references for testicular volume. The objective of this study was to determine the testicular volume by ultrasound in Turkish boys aged between 0 and 8 years.
    Methods: A total of 320 boys with bilaterally descended testes underwent scrotal ultrasound examinations. The testicular volume (mL) was calculated by the empirical formula of Lambert (V=L × T × AP × 0.71) and the formula for an ellipsoid (V=L × T × AP × 
    Results: The median (IQR) volume of the right and left testis were 0.75 (0.57-0.99) and 0.72 (0.56-0.98) mL (formula of Lambert), respectively; and 0.56 (0.42-0.73) and 0.53 (0.41-0.72) mL, (formula for an ellipsoid), respectively. The age-specific median of the average volume of the right and left testis estimated by the Lambert equation in the first five years was measured between 0.63 and 0.71 mL, followed by an increase to about 1.31 mL at the age of 8. This increase was highly statistically significant (p<0.0001). No significant association was found between the Z-scores for weight, height, and BMI of boys and the testicular volumes.
    Conclusions: This study provides the first national ultrasound-based estimates for testicular volume in Turkish boys aged 0-8 years.
    MeSH term(s) Body Height ; Child ; Child, Preschool ; Humans ; Infant ; Infant, Newborn ; Male ; Organ Size ; Testicular Diseases ; Testis/diagnostic imaging ; Ultrasonography
    Language English
    Publishing date 2022-02-17
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1231070-0
    ISSN 2191-0251 ; 0334-018X
    ISSN (online) 2191-0251
    ISSN 0334-018X
    DOI 10.1515/jpem-2021-0635
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Sonographic evaluation of normal thyroid volume and thyroid isthmus depth among infants in the west coast of Turkey.

    Çolak, Edis / Özkan, Behzat

    Endokrynologia Polska

    2022  Volume 73, Issue 2, Page(s) 325–329

    Abstract: Introduction: The reference values for thyroid volume (TV) suggested by the WHO are recommended for children aged 6 to 12 years and cannot be considered relevant for infants. The present study aimed to establish the normal values for TV and thyroid ... ...

    Abstract Introduction: The reference values for thyroid volume (TV) suggested by the WHO are recommended for children aged 6 to 12 years and cannot be considered relevant for infants. The present study aimed to establish the normal values for TV and thyroid isthmus depth (TID) in infants aged between 1 and 12 months from the west coast of Turkey.
    Material and methods: The TV and TID were measured in 223 infants by a validated ultrasound technique. The TV was determined by the method of Brunn et al. and Brown et al. The 3rd, 25th, 50th, 75th, and 97th percentiles of the TV and TID according to age were produced. The TV and TID measurements were compared with infants' age, gender, and standard deviation (Z) scores for weight, height, and BMI.
    Results: The median (IQR) values for TV were 0.77 (0.61-1.00) and 0.84 (0.67-1.10) mL, calculated according to the formula of Brunn et al. and Brown et al., respectively. The TV was significantly associated with age, and Z scores for weight, height, and body mass index (BMI) (r = 0.366, p < 0.001; r = 0.343, p < 0.0001; r = 0.269, p < 0.0001; and r = 0.157, p = 0.019; respectively). The median (IQR) value for the TID was 1.5 (1.3-1.9) mm. The TID was significantly correlated with TV and the Z score for height (r = 0.190, p = 0.004; and r = 0.144, p = 0.032; respectively). In multivariable regression, the only independent predictor for TV was the Z score for BMI. No differences based on gender were found.
    Conclusions: This is the first study to report the normative values for TV and TID in healthy Turkish infants aged up to 12 months. Our findings may serve as a basis for developing national and international references for TV and TID in infants.
    MeSH term(s) Body Height ; Body Mass Index ; Body Weight ; Child ; Humans ; Infant ; Reference Values ; Thyroid Gland/diagnostic imaging ; Turkey ; Ultrasonography
    Language English
    Publishing date 2022-04-05
    Publishing country Poland
    Document type Journal Article
    ZDB-ID 419270-9
    ISSN 2299-8306 ; 0423-104X
    ISSN (online) 2299-8306
    ISSN 0423-104X
    DOI 10.5603/EP.a2022.0012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Genetic Polymorphism on Chromosome 4q25 (rs17570669) May Predict Recurrence After Successful Electrical Cardioversion in Patients with Persistent Atrial Fibrillation.

    Ulus, Taner / Aliyev, İlkin / Arslan, Serap / Çilingir, Oğuz / Çolak, Ertuğrul

    Turk Kardiyoloji Dernegi arsivi : Turk Kardiyoloji Derneginin yayin organidir

    2024  Volume 51, Issue 8, Page(s) 550–556

    Abstract: Objective: Direct current electrical cardioversion (DCCV) is an effective rhythm-control option for patients with atrial fibrillation (AF). Despite initial success, a high recurrence rate remains a significant challenge. There is limited data on the ... ...

    Title translation Kromozom 4q25 (Rs17570669) Üzerindeki Genetik Polimorfizm Dirençli Atriyal Fibrilasyon Hastalarında Başarılı Elektriksel Kardiyoversiyon Sonrası Nüksü Belirleyebilir.
    Abstract Objective: Direct current electrical cardioversion (DCCV) is an effective rhythm-control option for patients with atrial fibrillation (AF). Despite initial success, a high recurrence rate remains a significant challenge. There is limited data on the genetic predictors of AF recurrence following successful DCCV. In this study, we aimed to evaluate whether 11 single nucleotide polymorphisms (SNPs) previously associated with AF are also linked to recurrence after DCCV in the Turkish population.
    Methods: Seventy-five patients with persistent AF, who achieved stable sinus rhythm following DCCV, were included in the study. The patients were prospectively monitored for the onset of AF recurrence. Clinical characteristics and SNPs were analyzed and compared between patients who experienced recurrence and those who did not.
    Results: The average age of the patients was 61.9 ± 11.5, and 33 (44%) were female. Over an average follow-up period of 17.0 (11.0-25.0) months, AF recurrence was observed in 38 patients (50.7%). A SNP in the PITX2 gene (rs17570669) (OR: 9.00, 95% Confidence Interval (CI): 1.28-63.02) and another in the ZFHX3 gene (rs2106261) (OR: 8.96, 95% CI: 1.03-77.66) were notably associated with AF recurrence in the additive model (P = 0.027 and 0.047, respectively). Multivariate Cox regression analysis revealed that the rs17570669 SNP was the sole independent predictor of AF recurrence (Hazard Ratio (HR): 3.59, 95% CI: 1.05-12.21, P = 0.040).
    Conclusion: The SNP in the paired-like homeodomain 2 (PITX2) gene (rs17570669) emerges as an independent predictor for AF recurrence after successful electrical cardioversion.
    MeSH term(s) Humans ; Female ; Male ; Atrial Fibrillation/genetics ; Atrial Fibrillation/therapy ; Electric Countershock ; Polymorphism, Single Nucleotide ; Chromosomes ; Recurrence
    Language English
    Publishing date 2024-03-27
    Publishing country Turkey
    Document type Journal Article
    ZDB-ID 1215217-1
    ISSN 1308-4488 ; 1016-5169
    ISSN (online) 1308-4488
    ISSN 1016-5169
    DOI 10.5543/tkda.2023.37679
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Capsaicin Alters the Expression of Genetic and Epigenetic Molecules In Hepatocellular Carcinoma Cell.

    Ates, Beren / Öner, Çağrı / Akbulut, Zeynep / Çolak, Ertuğrul

    International journal of molecular and cellular medicine

    2023  Volume 11, Issue 3, Page(s) 236–243

    Abstract: Capsaicin is a natural product which is extracted from pepper and has the potential to be used in cancer treatment because of its anti- proliferative effects. The aim of the study was to determine the effect of capsaicin on the hepatocellular carcinoma ... ...

    Abstract Capsaicin is a natural product which is extracted from pepper and has the potential to be used in cancer treatment because of its anti- proliferative effects. The aim of the study was to determine the effect of capsaicin on the hepatocellular carcinoma cell proliferation and the expressions of related genetic markers as Ki-67, PI3K/AKT/mTOR and epigenetic markers as miR-126 and piR-Hep-1. The inhibitory concentration of capsaicin in HepG2 cells was determined. piR-Hep-1 and miR-126 expressions and Ki-67, PI3K, AKT and mTOR gene expressions were examined by RT-PCR. The inhibitory concentration of capsaicin for HepG2 cells was 200 nM and the decreased proliferation was observed at 24
    Language English
    Publishing date 2023-08-16
    Publishing country Iran
    Document type Journal Article
    ZDB-ID 2697015-6
    ISSN 2251-9645 ; 2251-9637
    ISSN (online) 2251-9645
    ISSN 2251-9637
    DOI 10.22088/IJMCM.BUMS.11.3.236
    Database MEDical Literature Analysis and Retrieval System OnLINE

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