Influence of load on the recycling stability of nanospheres attached platinium ion for determination of glucose

Elvan Hasanog˘lu O¨ zkan,Nurdan Kurnaz Yetim,Dilek Nartop,Nurs¸ en Sarı 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.25 No.-

New nanospheres have been prepared with Pt2+ and Pt4+ for compare enzymatic properties of glucose oxidase enzyme (GOx). In this study nanoparticles, (aminomethyl)polystyrene (APS), 2-hydroxy-5- methylbenzaldehyde and Pt2+/Pt4+ have been synthesized by means of template and investigated the enzymatic properties of glucose oxidase enzyme (GOx) immobilized on there. The characteristics of the immobilized glucose oxidase (APS–Pt2+–GOx and APS–Pt4+–GOx) enzyme showed one optimum pH value. The influence of temperature, reusability and storage capacity on the free and immobilized glucose oxidase enzyme have been investigated. It is found that nanosphere including platinium atom exhibits excellent performance as the immobilized supporter of GOx, the immobilized enzyme demonstrates perfected storage and recycling stability. APS–Pt2+–GOx retains more than 30% of the initial activity after 32 successive cycles, which is a remarkable result.

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Elvan Onem Ozbilen,Hanife Nuray Yilmaz,Nazan Kucukkeles 대한치과교정학회 2019 대한치과교정학회지 Vol.49 No.3

Influence of Mechanical Alloying Time on Microstructure and Wear Behaviors of Fe–Cu–C Alloy

Elvan Büyükkayacı,İjlal Şimşek,Dursun Özyürek 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.11

In the present study, the influence of mechanical alloying time on microstructure and wear behavior was investigated for Fe–Cu–C alloy produced with powder metallurgy method. Within the scope of the study, Fe, Cu and C powders were mechanicalalloyed using various milling time (15, 30, 60, 90 and 120 min). After pressing (600 MPa) compacts were produced, thealloy powders were sintered for 1 h at 1150 °C in the atmosphere-controlled furnace. After sintering, the specimens wereprepared for microstructure examinations and wear testing. Wear tests were done using pin-on-disc device under variousloads (10–30 N), sliding distances (400–2000 m) and 1 ms−1 constant sliding speed. Result of the study showed that powdersize increased in Fe–Cu–C alloys up to 60 min mechanical alloying time. Maximum density and hardness values in Fe–Cu–Calloys were obtained in Fe–Cu–C alloy with 60 min mechanical alloying. In addition, the highest weight loss in wear testswas achieved in 120 min MA’ed specimen, while the lowest weight loss was achieved in 60 min MA’ed one.

Prostaglandin F receptor expression in intrauterine tissues of pregnant rats

Elvan Anadol,Halit Kanca,Atiye Seda Yar,Fatma Helvacioğlu,Sevda Menevşe,Engin Ҫalgüner,Deniz Erdoğan 대한수의학회 2014 Journal of Veterinary Science Vol.15 No.1

In this investigation, we studied the expression andlocalization of rat prostaglandin F (FP) receptor in uterinetissues of rats on gestational Days 10, 15, 18, 20, 21, 21.5 andpostpartal Days 1 and 3 using Western blotting analysis,real-time PCR, and immunohistochemistry. A high level ofimmunoreactivity was observed on gestational Days 20, 21,and 21.5 with the most significant signals found on Day 20. FP receptor protein was expressed starting on gestationalDay 15, and a fluctuating unsteady increase was observeduntil delivery. Uterine FP receptor mRNA levels were lowbetween Days 10 and 18 of gestation (p < 0.05). Thetranscript level increased significantly on Day 20 andpeaked on Day 21.5 just before labor (p < 0.05). There wasa positive correlation between FP receptor mRNAexpression and serum estradiol levels (rs = 0.78; p < 0.01)along with serum estradiol/progesterone ratios (rs = 0.79; p < 0.01). In summary, we observed an increase FP receptorexpression in rat uterus with advancing gestation, a markedelevation of expression at term, and a concominant decreaseduring the postpartum period. These findings indicate a rolefor uterine FP receptors in the mediation of uterinecontractility at term.

Comparison of the effects of rapid maxillary expansion and alternate rapid maxillary expansion and constriction protocols followed by facemask therapy

Elvan Onem Ozbilen,Hanife Nuray Yilmaz,Nazan Kucukkeles 대한치과교정학회 2019 대한치과교정학회지 Vol.49 No.1

Objective: The aim of this retrospective study was to evaluate and compare the changes in the pharyngeal airway (PA), maxillary sinus volume, and skeletal parameters after rapid maxillary expansion (RME) and alternate rapid maxillary expansion and constriction (Alt-RAMEC) followed by facemask (FM) therapy. Methods: The records of 40 patients with skeletal Class III malocclusion due to maxillary retrognathism were collected, and the patients were assigned into two groups. The first group comprised 8 male and 12 female patients (mean age, 10.0 ± 1.1 years) treated using RME/FM for an average of 10 months. The second group comprised 10 male and 10 female patients (mean age, 9.64 ± 1.3 years) treated using Alt-RAMEC/FM for an average of 12 months. Cone-beam computed tomography images acquired before (T0) and after treatment (T1) were evaluated. Results: Regarding the skeletal effects, significant differences between the groups were the increase in ANS-HRP (perpendicular distance of ANS to the horizontal reference plane, 0.99 mm, p <0.05) in the Alt-RAMEC/FM group and the decrease in PP-SN (palatal plane to Sella-Nasion plane, 0.93o, p < 0.05) in the RME/FM group. Maxillary sinus volumes increased significantly in both the groups, and the increase was statistically significantly higher in the Alt- RAMEC/FM group. Although no significant intergroup differences were observed in PA volumes, both lower (1,011.19 mm3) and total (1,601.21 mm3), PA volume increased significantly in the Alt-RAMEC/FM group. Conclusions: The different expansion devices and protocols used with FM therapy do not seem to affect the forward movement of the maxilla and PA volumes. In contrast, the increase in maxillary sinus volume was greater in the Alt-RAMEC/FM protocol.

Cell-specific and post-hoc spatial clustering tests based on nearest neighbor contingency tables

Elvan Ceyhan 한국통계학회 2017 Journal of the Korean Statistical Society Vol.46 No.2

Spatial clustering patterns in a multi-class setting such as segregation and association between classes have important implications in various fields, e.g., in ecology, and can be tested using nearest neighbor contingency tables (NNCTs). A NNCT is constructed based on the types of the nearest neighbor (NN) pairs and their frequencies. We survey the cell-specific (or pairwise) and overall segregation tests based on NNCTs in literature and introduce new ones and determine their asymptotic distributions. We demonstrate that cell-specific tests enjoy asymptotic normality, while overall tests have chi-square distributions asymptotically. Some of the overall tests are confounded by the unstable generalized inverse of the rank-deficient covariance matrix. To overcome this problem, we propose rank-based corrections for the overall tests to stabilize their behavior. We also perform an extensive Monte Carlo simulation study to compare the finite sample performance of the tests in terms of empirical size and power based on the asymptotic and Monte Carlo critical values and determine the tests that have the best size and power performance and are robust to differences in relative abundances (of the classes). In addition to the cell-specific tests, we discuss one(-class)-versus-rest type of tests as posthoc tests after a significant overall test. We also introduce the concepts of total, strong, and partial segregation/association to differentiate different levels of these patterns. We compare the new tests with the existing NNCT-tests in literature with simulations and illustrate the tests on an ecological data set.

Does surgically assisted maxillary protraction with skeletal anchorage and Class III elastics affect the pharyngeal airway? A retrospective, long-term study

Elvan Onem Ozbilen,Petros Papaefthymiou,Hanife Nuray Yilmaz,Nazan Küçükkeleş 대한치과교정학회 2023 대한치과교정학회지 Vol.53 No.1

Objective: Surgically assisted maxillary protraction is an alternative protocol in severe Class III cases or after the adolescent growth spurt involving increased maxillary advancement. Correction of the maxillary deficiency has been suggested to improve pharyngeal airway dimensions. Therefore, this retrospective study aimed to analyze the airway changes cephalometrically following surgically assisted maxillary protraction with skeletal anchorage and Class III elastics. Methods: The study population consisted of 15 Class III patients treated with surgically assisted maxillary protraction combined with skeletal anchorage and Class III elastics (mean age: 12.9 ± 1.2 years). Growth changes were initially assessed for a mean of 5.5 ± 1.6 months prior to treatment. Airway and skeletal changes in the control (T0), pre-protraction (T1), post-protraction (T2), and follow-up (T3) periods were monitored and compared using lateral cephalometric radiographs. Statistical significance was set at p < 0.05. Results: The skeletal or airway parameters showed no statistically significant changes during the control period. Sella to nasion angle, N perpendicular to A, Point A to Point B angle, and Frankfort plane to mandibular plane angle increased significantly during the maxillary protraction period (p < 0.05), but no significant changes were observed in airway parameters (p > 0.05). No statistically significant changes were observed in the airway parameters in the follow-up period either. However, Sella to Gonion distance increased significantly (p < 0.05) during the follow-up period. Conclusions: No significant changes in pharyngeal airway parameters were found during the control, maxillary protraction, and follow-up periods. Moreover, the significant increases in the skeletal parameters during maxillary protraction were maintained in the long-term.

Potential of AKT2 expression as a predictor of lymph-node metastasis in invasive breast carcinoma of no special type

Primariadewi Rustamadji,Elvan Wiyarta,Kristina Anna Bethania,Kusmardi Kusmardi 대한병리학회 2021 Journal of Pathology and Translational Medicine Vol.55 No.4

Background: Invasive breast carcinoma of no special type (IBC-NST) is the most common type of breast cancer and mainly causes regional lymph-node metastasis (LNM). We investigated the potential for AKT2 expression as a predictive biomarker for LNM in IBC-NST.Methods: Forty-eight paraffin blocks containing IBC-NST primary tumors were divided into two groups based on presence or absence of LNM. Age, tumor grade, tumor size, lymphovascular invasion (LVI), and AKT expression were assessed. AKT2 expression was assessed based on immunohistochemical staining, while other data were collected from archives. Results: Multiple logistic regression results showed that AKT2 expression and LVI were significantly associated with LNM (odds ratio [OR], 5.32; 95% confidence interval [CI], 1.42 to 19.93 and OR, 4.46; 95% CI, 1.17 to 16.97, respectively). AKT2 expression was able to discriminate against LNM (area under the receiver operating characteristic, 0.799 ± 0.063; 95% CI, 0.676 to 0.921) at an H-score cutoff of 104.62 (83.3% sensitivity, 62.5% specificity). Conclusions: AKT2 expression has potential as a predictor of LNM in IBC-NST. The H-score cutoff for AKT2 expression can be used as a classification guide in future studies.

Real Life Data of Treat and Extend Intravitreal Ranibizumab and Aflibercept Therapy in Wet Age-related Macular Degeneration Patients: 3-Year Results

Ozgul Ugurtay,Alev Kockar,Elvan Alper Sengul 대한안과학회 2021 Korean Journal of Ophthalmology Vol.35 No.4

Purpose: To compare functional and anatomic outcome of intravitreal ranibizumab (IVR) and intravitreal aflibercept (IVA) treatments in neovascular age-related macular degeneration by using the treat and extend (TE) protocol. Methods: In this retrospective chart study, treatment naïve 74 eyes of 74 age-related macular degeneration patients treated with IVR and IVA (38 eyes in IVR and 36 eyes in IVA group) with TE protocol were included. Following three consecutive monthly intravitreal injections, TE protocol was applied to each group. Patients were followed up for at least 36 months. Mean change in best-corrected visual acuity (BCVA), central macula thickness (CMT) and injection numbers over 3 years were compared. Results: Among 36 months period, the mean number of injections was 17 ± 4 for both groups (p > 0.05). In terms of CMT, there was no statistically significant difference between groups at 36 months compared to baseline. A decrease of 72.55 ±39.37 μm in CMT was detected in IVR group, whereas the decrease was 70.58 ± 33.96 μm in IVA group (p > 0.05). There was a significant increase in BCVA at 36 months of measurements. In addition, BCVA demonstrated an increase of 4.1 ± 0.44 letters in IVR group and 4.36 ± 0.67 letters in IVA group after 36 months compared to the baseline (p > 0.05). Conclusions: Both IVR and IVA injections provided significant improvements and stability in BCVA and CMT, however there was no significant difference between IVR and IVA injections with TE protocol of 36 months.

Paliperidone Palmitate-induced Urinary Incontinence: A Case Report

Ersin Hatice Karslıoglu,Elvan Özalp,Ali Çayköylü 대한정신약물학회 2016 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.14 No.1

Urinary incontinence, although rarely reported, is one of the most important adverse effects of antipsychotic medication. It can be an embarrassing, distressing, and potentially treatment-limiting. Several antipsychotics, including both typical and atypical varieties, are known to induce urinary incontinence. Many antipsychotic drugs target the neural pathways controlling continence by binding to receptors of some neurotransmitters such as serotonin, dopamine, acetylcholine, and adrenaline. Pharmacological management of incontinence should be considered if there is a risk of cessation of the antipsychotic therapy or any decline in patients' compliance. Amitriptyline, desmopressin, ephedrine, and anticholinergics such as oxybutynin and trihexyphenidyl are the most frequently used agents to treat incontinence. We think that the frequency of incontinence is higher than reported in the literature, and that follow-up routines should include a form of standardized screening for all possible adverse effects, including incontinence, of any given antipsychotic. In this article, we report a case of urinary incontinence as an adverse effect of paliperidone palmitate use during maintenance therapy in a patient with schizophrenia.