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    PublicationOpen Access
    25-hydroxyvitamin D levels are low but not associated with disease activity in chronic spontaneous urticaria and depression
    (AEPress, 2020) Vurgun, Eren; Güntaş, Gürkan; Kocatürk Göncü, Özgür Emek; Memet, Bachar; Doctor; School of Medicine; Koç University Hospital; 217219; N/A
    Aim: to evaluate vitamin D levels in patients with chronic spontaneous urticaria (CSU), depression and both of them, thus to fi nd out whether vitamin D may be a common causative factor of CSU and depression. Methods: thirty patients with CSU, 30 patients with depression, 30 patients with both CSU and depression and 30 healthy volunteers as control group were involved in the study. Serum 25-hydroxyvitamin D (25(OH) D) levels of these groups were measured and compared. Correlations between 25(OH)D levels and the activity of CSU and depression were analyzed. Results: healthy controls' 25(OH)D levels (17.2±8.8 ng/mL) were higher than patients with CSU (9.1±5.1 ng/mL), depression (8.9±6.1 ng/mL) and CSU with depression (7.7±4.7 ng/mL) (p<0.001, p<0.001 and p<0.001, respectively). There were no differences in 25(OH)D levels between CSU patients with and without depression, between depression patients and CSU patients with and without depression (p=0.43, p=0.82 and p=0.92, respectively). There were no correlations between 25(OH)D levels and the activity of CSU or depression (p=0.99 and p=0.76, respectively). Conclusion: Lower 25(OH)D levels in CSU and/or depression may appear as a secondary phenomenon, which means being result of these diseases rather than the cause (Tab. 1, Fig. 2, Ref. 41).
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    PublicationOpen Access
    A comparison of glycemic parameters and their relationship with C-peptide and Proinsulin levels during partial remission and non-remission periods in children with type 1 diabetes mellitus-a cross-sectional study
    (BioMed Central, 2021) Çakır, Esra Papatya; Yeşiltepe Mutlu, Rahime Gül; Çapacı, Merve; Can, Ecem; Gökçe, Tuğba; Bayrakçı, Gizem; Muradoğlu, Serra Küpçüoğlu; İncir, Said; Hatun, Şükrü; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 153511; N/A; N/A; N/A; N/A; N/A; N/A; 153504
    Background: currently, there is a lack of data relating to glycemic parameters and their relationship with C-peptide (CP) and proinsulin (PI) during the partial remission period (PRP) in type 1 diabetes mellitus (T1D). The aim of this study was to evaluate glycemic parameters in children with T1D who are in the PRP using intermittently scanned continuous glucose monitoring systems (isCGMS) and to investigate any relationships between CP and PI levels. Methods: the study included 21 children who were in the PRP and 31 children who were not. A cross-sectional, non-randomized study was performed. Demographic, clinical data were collected and 2 week- isCGMS data were retrieved. Results: the Serum CP showed a positive correlation with time-in-range in the PRP (p:0.03), however PI showed no correlations with glycemic parameters in both periods. The Serum CP and PI levels and the PI:CP ratio were significantly higher in the PRP group than in the non-PRP group. In the non-PRP group, the PI level was below 0.1 pmol/L (which is the detectable limit) in only 2 of the 17 cases as compared with none in the PRP group. Similarly, only 2 of the 17 children in the non-PRP group had CP levels of less than 0.2 nmol / L, although both had detectable PI levels. Overall time-in-range (3. 9-1.0 mmol/L) was significantly high in the PRP group. In contrast, the mean sensor glucose levels, time spent in hyperglycemia, and coefficient of variation levels (32.2vs 40.5%) were significantly lower in the PRP group. Conclusions: although the mean glucose and time in range during the PRP was better than that in the non-PRP group, the glycemic variability during this period was not as low as expected. While the CP levels showed an association with TIR during the PRP, there was no correlation between PI levels and glycemic parameters. Further studies are needed to determine if PI might prove to be a useful parameter in clinical follow-up.
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    PublicationOpen Access
    A new prognostic model for primary sclerosing cholangitis
    (Aves, 2019) Acar, Sencan; N/A; Akyıldız, Murat; Faculty Member; School of Medicine
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    PublicationOpen Access
    A new risk-scoring system for colorectal cancer and polyp screening by Turkish Colorectal Cancer and Polyp Study Group
    (Aves, 2022) Erdem, L.; Akbal, E.; Koçak, E.; Tucer, D.; Üçbilek, E.; Uyanıkoğlu, A.; Dolapçıoğlu, C.; Şirin, G.; Alkım, H.; Soylu, A.; Doğanay, L.; Kürbüz, A.K.; Özdil, K.; Alagözlü, H.; Erürker Öztürk, T.; Sezikli, M.; Adalı, G.; Çoban, M.; Hülagü, S.; Değertekin, H.; Atasoy, A.; Akyüz, F.; Gaffarlı, İ.; Saruç, M.; Altıntaş, E.; Sezgin, O.; Tözün N.; Ahıshalı, Emel; School of Medicine
    Background: colorectal cancer is one of the most commonly diagnosed types of cancer worldwide. An early diagnosis and detection of colon cancer and polyp can reduce mortality and morbidity from colorectal cancer. Even though there are a variety of options in screening tests, the question remains on which test is the most effective for the early detection of colorectal cancer. In this prospective study, we aimed to develop a simple, useful, effective, and reliable scoring system to detect colon polyp and colorectal cancer. Methods: we enrolled 6508 subjects over the age of 18 from 16 centers, with colonoscopy screening. The age, smoking status, alcohol consumption, body mass index, polyp incidence, polyp size, number and localization, and pathologic findings were recorded. Results: the age, male gender, obesity, smoking, and family history were found as independent risk factors for adenomatous polyp. We have developed a new scoring system which can be used for these factors. With a score of 4 or above, we found the following: sensitivity 81%, specificity 40%, positive predictive value 25.68%, and negative predictive value 89.84%, for adenomatous polyp detection; and sensitivity 96%, specificity 39%, positive predictive value 3.35%, negative predictive value 99.29%, for colorectal cancer detection. Conclusion: even though the first colorectal cancer screening worldwide is generally performed for individuals over 50 years of age, we recommend that screening for colorectal cancer might begin for those under 50 years of age as well. Individuals with a score ? 4 must be included in the screening tests for colorectal cancer.
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    PublicationOpen Access
    A rehabilitation protocol for patients with lumbar degenerative disc disease treated with posterior transpedicular dynamic stabilization
    (Turkish Neurosurgical Society, 2017) Ataker, Yaprak; Çerezci, Önder; Canbulat, Nazan; Öktenoğlu, Bekir Tunç; Sasani, Mehdi; Erçelen, Ömür; Süzer, Süleyman Tuncer; Özer, Ali Fahir; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Koç University Hospital; 58534; N/A; N/A; N/A; 221691; 1022
    AIM: To evaluate the efficacy of the rehabilitation protocol on patients with lumbar degenerative disc disease after posterior transpedicular dynamic stabilization (PTDS) surgery. MATERIAL and METHODS: Patients (n=50) with single level lumbar degenerative disc disease were recruited for this study. Patients had PTDS surgery with hinged screws. A rehabilitation program was applied for all patients. Phase 1 was the preoperative evaluation phase. Phase 2 (active rest phase) was the first 6 weeks after surgery. During phase 3 (minimal movement phase, 6-12 weeks) pelvic tilt exercises initiated. In phase 4 (dynamic phase, 3-6 months) dynamic lumbar stabilization exercises were started. Phase 5 (return to sports phase) began after the 6th month. The primary outcome criteria were the Visual Analogue Pain Score (VAS) and the Oswestry Disability Index (ODI). Patients were evaluated preoperatively, postoperative 3rd, 12th and 24th months. RESULTS: The mean preoperative VAS and ODI scores were 7.52±0.97 and 60.96±8.74, respectively. During the 3rd month, VAS and ODI scores decreased to 2.62±1.05 and 26.2±7.93, respectively. VAS and ODI scores continued to decrease during the 12th month after surgery to 1.4±0.81 and 13.72±6.68, respectively. At the last follow-up (mean 34.1 months) the VAS and ODI scores were found to be 0.68±0.62 and 7.88±3.32, respectively. (p=0.0001). CONCLUSION: The protocol was designed for a postoperative rehabilitation program after PTDS surgery for patients with lumbar degenerative disc disease. The good outcomes are the result of a combination of very careful and restrictive patient selection, surgical technique, and the presented rehabilitation program.
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    PublicationOpen Access
    Ai driven advanced internet of things (Iotx(2)): the future seems irreversibly connected in medicine
    (Turkish Society of Cardiology, 2019) Belcastro, Kristen D.; Department of Electrical and Electronics Engineering; Ergen, Onur; Department of Electrical and Electronics Engineering; College of Engineering; 272106
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    PublicationOpen Access
    Ambulatory arterial stiffness index is increased in obese children
    (Turkish National Pediatric Society, 2020) Gayret, Özlem Bostan; Taşdemir, Mehmet; Erginöz, Ergin; Bilge, İlmay; Doctor; Undergraduate Student; Faculty Member; School of Medicine; N/A; N/A; 198907
    Background and objectives: one way to measure arterial stiffness is the ambulatory arterial stiffness index (AASI), which is the relationship between diastolic and systolic ambulatory blood pressure (BP) over 24-hours. Methods: we studied the difference in AASI between obese and lean children. AASI was calculated from 24-hour ambulatory blood pressure monitoring in 53 obese children (33 girls) and compared with age-matched 42 healthy subjects (20 girls). Hypertension was defined according to the criteria of the American Heart Association. To evaluate inflammation, the blood level of high-sensitive C-reactive protein was measured. Results: the mean age was 10.6 +/- 2.83 years in obese children and 11.3 +/- 3.17 years in healthy subjects. Hypertension was determined in three (5.6%) obese children. The median heart rate-SDS, pulse pressure and blood pressure values did not differ between the two groups. The mean AASI was significantly higher in obese children compared to healthy subjects (0.42 +/- 0.15 vs. 0.29 +/- 0.18, p <0.001). AASI significantly correlated with nighttime SBP-SDS, nighttime SBP-load, systolic and diastolic nocturnal dipping, with no independent predictor. Conclusion: this study confirms that AASI is increased in obese children. AASI calculation is a useful, cost-effective, and an easy method to evaluate arterial stiffness. Early detection of increased arterial stiffness can help clinicians come up with preventive measures in the management of patients.
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    PublicationOpen Access
    Assessment of sleep pattern and quality before and after liver transplantation using different methods
    (Aves, 2020) Gençdal, Genco; Türker, Gamze; Gençdal, Işıl Yazıcı; Ekinci, Burçak; Acar, Şencan; Dinçkan, Ayhan; Akyıldız, Murat; Faculty Member; School of Medicine
    Background/aims: sleep disorders (SDs) are frequently seen in patients with liver cirrhosis. Polysomnography (PSG), actigraphy, and electroencephalogram (EEG) are the common objective methods to diagnose SDs. The most commonly used subjective methods are the Pittsburgh sleep quality index (PSQI) and Epworth sleepiness scale (ESS). We aimed to evaluate the effect of liver transplantation (LTx) on SDs using a combination of objective (PSG and EEG) and subjective (PSQI and ESS) methods. Materials and methods: a total of 18 patients with cirrhosis on an LTx waiting list were included in this study. Patient clinical status and biochemical parameters were evaluated. All patients completed the validated Turkish forms of the PSQI and ESS before and 9 months after LTx. All patients underwent EEG and PSG before and 9 months after LTx. Results: in total, 18 patients with liver cirrhosis (men: 12; 66.7%, mean age: 53.22 +/- 10.43 years) were included in this study. Pretransplant mean PSQI and ESS scores were 8.4 +/- 3.11 and 7.28 +/- 3.89, respectively; 9-month posttransplant mean PSQI and ESS scores were 4.5 +/- 2.8 and 4.72 +/- 2.91 (p<0.01), respectively. Before transplantation, metabolic encephalopathy was detected in 6 patients by EEG, whereas metabolic encephalopathy was detected in only 1 patient posttransplant. Posttransplantation PSG sleep duration (all stages) increased relative to pretransplant PSG values. Sleep latency and rapid eye movement latency were found to be reduced compared to the pretransplant values. Conclusion: this pilot study compared SDs in patients with pre- and post-LTx by combining the subjective and objective methods. Significant SD improvements were found at the 9th month.
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    PublicationOpen Access
    Baseline hemoglobin <11.0 g/dL has stronger prognostic value than anemia status in nasopharynx cancers treated with chemoradiotherapy
    (Sage, 2019) Topkan, Erkan; Ekici, Nur Yücel; Özdemir, Yurday; Besen, Ali Ayberk; Yıldırım, Berna Akkuş; Mertsoylu, Hüseyin; N/A; Sezen, Duygu; Selek, Uğur; Faculty Member; Faculty Member; School of Medicine; N/A; 27211
    Background: to retrospectively investigate the influence of pretreatment anemia and hemoglobin levels on the survival of nasopharyngeal carcinoma patients treated with concurrent chemoradiotherapy (C-CRT). Methods: a total of 149 nasopharyngeal carcinoma patients who received C-CRT were included. All patients had received 70 Gy to the primary tumor plus the involved lymph nodes, and 59.4 Gy and 54 Gy to the intermediate- and low-risk neck regions concurrent with 1-3 cycles of cisplatin. Patients were dichotomized into non-anemic and anemic (hemoglobin <12 g/dL (women) or <13 g/dL (men)) groups according to their pre-treatment hemoglobin measures. Receiver operating characteristic (ROC) curve analysis was utilized for accessibility of a pre-treatment hemoglobin cut-off that impacts outcomes. Potential interactions between baseline anemia status and hemoglobin measures and overall survival, locoregional progression-free survival (LRPFS), and progression-free survival were assessed. Results: Anemia was evident in 36 patients (24.1%), which was related to significantly shorter overall survival (P=0.007), LRPFS (P<0.021), and progression-free survival (P=0.003) times; all three endpoints retained significance in multivariate analyses (P<0.05, for each). A baseline hemoglobin value of 11.0 g/dL exhibited significant association with outcomes in ROC curve analysis: hemoglobin <11.0 g/dL (N=26) was linked with shorter median overall survival (P<0.001), LRPFS (P=0.004), and progression-free survival (P<0.001) times, which also retained significance for all three endpoints in multivariate analyses and suggested a stronger prognostic worth for the hemoglobin Conclusion: pre-C-CRT hemoglobin <11.0 g/dL has a stronger prognostic worth than the anemia status with regard to LRPFS, progression-free survival, and overall survival for nasopharyngeal carcinoma patients.
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    PublicationOpen Access
    Baseline low prognostic nutritional index predicts poor survival in locally advanced nasopharyngeal carcinomas treated with radical concurrent chemoradiotherapy
    (Sage, 2019) N/A; Selek, Uğur; Faculty Member; School of Medicine; 27211
    Background: to retrospectively assess the impact of prognostic nutritional index (PNI) on survival outcomes of patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) treated with concurrent chemoradiotherapy (CCRT). Methods: this study incorporated 154 patients with LA-NPC who received exclusive cisplatinum-based CCRT. Receiver operating characteristic (ROC) curve analysis was utilized for accessibility of pretreatment PNI cutoffs influencing survival results. The primary end point was the interaction between the overall survival (OS) and PNI values, while cancer-specific survival (CSS) locoregional progression-free survival (LR-PFS), distant metastasis–free survival (DMFS), and PFS were the secondary end points. Results: a rounded PNI cutoff value of 51 was identified in ROC curve analyses to exhibit significant link with CSS, OS, DMFS, and PFS outcomes, but not LR-PFS. Patients grouping per PNI value (≥51 [N = 95] vs <51 [N = 49]) revealed that PNI < 51 group had significantly shorter median CSS (P <.001), OS (P <.001), DMFS (P <.001), and PFS (P <.001) times than the PNI ≥ 51 group, and the multivariate results confirmed the PNI < 51 as an independent predictor of poor outcomes for each end point (P <.05 for each). The unfavorable impact of the low PNI was also continued at 10-year time point with survival rates of 77.9% versus 42.4%, 73.6% versus 33.9%, 57.9% versus 27.1%, and 52.6% versus 23.7% for CSS, OS, DMFS, and PFS, respectively. Additionally, we found that PNI < 51 was significantly associated with higher rates of weight loss >5% over past 6 months (49.2% versus 11.6%; P =.002) compared to PNI < 51 group. Conclusion: low pre-CCRT PNI levels were independently associated with significantly reduced CSS, OS, DMFS, and PFS outcomes in patients with LA-NPC treated with definitive CCRT.