N-vinylcaprolactam-based temperature and pH-sensitive graft hydrogels for controlled drug release of 5-FU: a comprehensive study on synthesis, characterization, and release kinetics

İ. K. Akbay,T. Özdemir 한국고분자학회 2024 Macromolecular Research Vol.32 No.3

Stimuli-responsive polymers can be used for various purposes due to their amazing properties within the context of controlled release systems. In this study, the aim was to prepare hydrogels that are stimulus-responsive to temperature and pH and utilize them in drug release investigations. N-Vinyl caprolactam-based polymers were synthesized and optimized based on the swelling ratio data. Both temperature and pH sensitivity, along with their respective transition values, were determined. The best sample was selected based on 5-FU encapsulation efficiency. To enhance the swelling ratio and encapsulation values, different amounts of poly-(ethylene glycol) were added to improve water swelling ratio and 5-FU release properties. All obtained samples were characterized using water swelling ratio, SEM, FTIR, and DSC analyses. Additionally, the encapsulation and release of the 5-FU drug from the hydrogels were studied. According to the results, it was understood that it could release the 5-FU drug approximately 14% when below the transition temperature and pH value, and approximately 99% when above the transition temperature and pH value. The kinetics of the drug release were thoroughly examined. The results of thekinetic study revealed a drug release pattern consistent with Fick's law.

How Does Spousal Support Affect Women’s Quality of Life in the Postpartum Period in Turkish Culture?

Ay?e Sevim Akbay,Emel Ta?cı-Duran 숙명여자대학교 아시아여성연구원 2018 Asian Women Vol.34 No.3

The purpose of this study is to determine the relationship between spousal support and postpartum women’s quality of life. This is a descriptive study carried out between July 1, 2014 and October 31, 2014. Data were collected from the homes of 301 women who were in the postpartum period. A demographic questions form, the Maternal Postpartum Quality of Life Questionnaire (MPQLQ), and the Spouse Support Scale (SSS) were used to collect the data. According to the results, there was a moderate positive relationship between general spousal support and quality of life after birth. The age of the participating women, the educational status of the women and their spouses, the duration of their marriage, the type of delivery, whether the pregnancy was planned/unplanned, acceptance of the baby after learning of the pregnancy, the type of marriage, spouses’ relationships, work hours of the spouse, and time spent at home were important variables for determining spousal support and quality of life. The relationship between general spousal support and postpartum quality of life in this study suggests that support of spouses is important in improving the maternal quality of life in the postpartum period. This study contributes to the importance of postpartum support of spouses and the importance of spousal awareness in this regard.

Effect of application factors on optimum design of reinforced concrete retaining systems

Aylin Ece Kayabekir,Zülal Akbay Arama,Gebrail Bekdaş 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.80 No.2

Retaining walls and cantilever soldier pile walls are both can be used in interchangeable manner so it is so important to evaluate the relationship between the cost and sizing. In this paper, an investigation of the effect of the design restraints and cost limits of both reinforced concrete retaining walls and cantilever soldier pile walls on optimum design is done. Pure frictional soils are evaluated as the surrounding soil medium of retaining structures and Rankine lateral earth pressure theory is used to derive the lateral thrust effected through the selected retaining systems. Fictionalized different cases are created for all retaining systems to compare optimal dimensions and minimum costs for the same project requirements. Jaya algorithm is used to perform optimization process. Parametrical analyses are conducted according to change of excavation depth, unit weight of soil, and cost of concrete, surcharge load and workmanship multiplier. The results of the parametric analysis has provided to suggest on the design and application differences of both retaining systems having regard to the effects of both cost and sizing simultaneously. As a consequence of the study, some limitations that have to be considered before design are given for the selection of proper retaining structure not to cause overinvestment.

Numerical modelling and finite element analysis of \r\nstress wave propagation for ultrasonic pulse velocity testing of concrete

Ismail Ozgur Yaman,Zekai Akbay,Haluk Aktan 한국계산역학회 2006 Computers and Concrete, An International Journal Vol.3 No.6

Stress wave propagation through concrete is simulated by finite element analysis. The concrete medium is modeled as a homogeneous material with smeared properties to investigate and establish the suitable finite element analysis method (explicit versus implicit) and analysis parameters (element size, and solution time increment) also suitable for rigorous investigation. In the next step, finite element analysis model of the medium is developed using a digital image processing technique, which distinguishes the mortar and aggregate phases of concrete. The mortar and aggregate phase topologies are, then, directly mapped to the finite element mesh to form a heterogeneous concrete model. The heterogeneous concrete model is then used to simulate wave propagation. The veracity of the model is demonstrated by evaluating the intrinsic parameters of nondestructive ultrasonic pulse velocity testing of concrete. Quantitative relationships between aggregate size and testing frequency for nondestructive testing are presented.

Effects of calcium silicate cements on neuronal conductivity

Deniz-Sungur Derya,Onur Mehmet Ali,Akbay Esin,Tan Gamze,Daglı-Comert Fügen,Sayın Taner Cem 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.2

Objectives This study evaluated alterations in neuronal conductivity related to calcium silicate cements (CSCs) by investigating compound action potentials (cAPs) in rat sciatic nerves. Materials and Methods Sciatic nerves were placed in a Tyrode bath and cAPs were recorded before, during, and after the application of test materials for 60-minute control, application, and recovery measurements, respectively. Freshly prepared ProRoot MTA, MTA Angelus, Biodentine, Endosequence RRM-Putty, BioAggregate, and RetroMTA were directly applied onto the nerves. Biopac LabPro version 3.7 was used to record and analyze cAPs. The data were statistically analyzed. Results None of the CSCs totally blocked cAPs. RetroMTA, Biodentine, and MTA Angelus caused no significant alteration in cAPs (p > 0.05). Significantly lower cAPs were observed in recovery measurements for BioAggregate than in the control condition (p < 0.05). ProRoot MTA significantly but transiently reduced cAPs in the application period compared to the control period (p < 0.05). Endosequence RRM-Putty significantly reduced cAPs. Conclusions Various CSCs may alter cAPs to some extent, but none of the CSCs irreversibly blocked them. The usage of fast-setting CSCs during apexification or regeneration of immature teeth seems safer than slow-setting CSCs due to their more favorable neuronal effects.

Facile and Fast Photo-Polymerization of N-Vinyl Caprolactam via UV-C Irradiation

Habil Uzun,Ahmet Gungor,?smail Kutlugun Akbay,Tonguc Ozdemir 한국고분자학회 2021 폴리머 Vol.45 No.1

Different polymerization techniques of poly(N-vinyl caprolactam) (PNVCL) have been reported including the photo polymerization via ultraviolet (UV). However, photo polymerization of PNVCL via UV-C (wavelength of 254 nm) has not been reported. In this study, N-vinyl caprolactam was polymerized via UV-C irradiation at different time periods. Fouirer transform infrared spectroscopy (FTIR) analysis showed that the PNVCL has been successfully synthesized via the photo polymerization method. The optimum conversion time was found as about 70 min and the conversion was found as 71.2%. Gels displayed different swelling behavior at temperatures above and below lower critical solution temperature (LCST), and swelling analysis, dynamic light scattering (DLS) and differential scanning calorimetry (DSC) were performed to investigate the phase change behavior. It was observed that LCST of the synthesized gels occurs between 31 and 35 oC determined by DSC analysis, which is also consistent with DLS and swelling analysis results. In conclusion, a facile and short time period polymerization technique is reported via use of UV-C photo polymerization technique.

The Effect of Stinging Nettle (Urtica dioica) Seed Oil on Experimental Colitis in Rats

Zeynep Genc,Aysen Yarat,Tugba Tunali-Akbay,Goksel Sener,Sule Cetinel,Rabia Pisiriciler,Esin Caliskan-Ak,Ayhan Altıntas,Betul Demirci 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.12

This study investigated the effect of Urtica dioica, known as stinging nettle, seed oil (UDO) treatment on colonic tissue and blood parameters of trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats. Experimental colitis was induced with 1mL of TNBS in 40% ethanol by intracolonic administration with a 8-cm-long cannula with rats under ether anesthesia, assigned to a colitis group and a colitis +UDO group. Rats in the control group were given saline at the same volume by intracolonic administration. UDO (2.5mL/kg) was given to the colitis +UDO group by oral administration throughout a 3-day interval, 5 minutes later than colitis induction. Saline (2.5 mL/kg) was given to the control and colitis groups at the same volume by oral administration. At the end of the experiment macroscopic lesions were scored, and the degree of oxidant damage was evaluated by colonic total protein, sialic acid, malondialdehyde (MDA), and glutathione levels, collagen content, tissue factor activity, and superoxide dismutase and myeloperoxidase activities. Colonic tissues were also examined by histological and cytological analysis. Pro-inflammatory cytokines (tumor necrosis factor-a, interleukin-1b, and interleukin-6), lactate dehydrogenase activity, and triglyceride and cholesterol levels were analyzed in blood samples. We found that UDO decreased levels of pro-inflammatory cytokines, lactate dehydrogenase, triglyceride, and cholesterol, which were increased in colitis. UDO administration ameliorated the TNBS-induced disturbances in colonic tissue except for MDA. In conclusion, UDO, through its anti-inflammatory and antioxidant actions, merits consideration as a potential agent in ameliorating colonic inflammation.

Histological and morphological development of the prepuce from birth to prepubertal age

Erim Erdem,Mustafa Kaplan Caliskan,Meryem Ilkay Karagul,Erdem Akbay,Banu Coskun Yilmaz,Yuksel Cem Aygun 대한비뇨의학회 2024 Investigative and Clinical Urology Vol.65 No.2

Purpose: To study the histological changes of the preputial tissue from birth to prepubertal age in order to define unnoticed morphological changes. Materials and Methods: Prepuce samples were obtained from 79 healthy boys who underwent routine ritual circumcision. Specimens were divided into six groups according to the boys’ age: newborn, 0–1 year of age, 2–3 years of age, 4–5 years of age, 6–7 years of age, and 8–9 years of age. Histologic analysis of the specimens was performed by H&E, Masson’s trichrome, Verhoeff–Von Gieson, immunohistochemical staining. Results: Microscopic examinations showed that average epithelial thickness increased after the neonatal period (p=0.001). When collagen fiber density was evaluated, no significant differences between groups were found (p=0.083). When the elastic fibers in the dermis were evaluated, it was determined that the number and thickness of elastic fibers increased with age. Immunohistochemical examinations showed that the number of peripheral nerves marked with S100 was lower in the neonatal period than at other ages (p=0.048). When the vessels marked with CD105 antibody were counted, there was no significant difference between the groups (p=0.078). Conclusions: This is the first study to examine the age-related structure of connective tissue elements in the foreskin. Our results showed that the prepuce’s prepubertal maturation process is continuous, and the first 2 years of life are appropriate not only in relation to the physiological effects of age but also the optimum structural changes for wound healing, such as vessel diameter, epithelium thickness, peripheral nerve count.

Clinical Significance of Atypical Squamous Cells of Undetermined Significance in Detecting Preinvasive Cervical Lesions in Post-Menopausal Turkish Women

Tokmak, Aytekin,Guzel, Ali Irfan,Ozgu, Emre,Oz, Murat,Akbay, Serap,Erkaya, Salim,Gungor, Tayfun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

Background: To evaluate the clinical significance of atypical squamous cells of undetermined significance (ASCUS) in PAP test in post-menopausal women and compare with reproductive age women. Materials and Methods: A total of 367 patients who referred to our gynecologic oncology clinic were included to the study between September 2012 and August 2013. Data for 164 post-menopausal (group 1) and 203 pre-menopausal (group 2) women with ASCUS cytology were evaluated retrospectively. Immediate colposcopy and endocervical curettage was performed for both groups and conization for all women with a result suggestive of CIN2-3. Histopathological results and demographic features of patients were compared between the two groups. Results: Mean age of the patients was $54.6{\pm}6.5$ years in group 1 and $38{\pm}6.6$ years in group 2. Some 14 (8.5%) of post-menopausal women and 36 (17.7%) of pre-menopausal women were current smokers (p=011). Totals of 38 (23.2%) post-menopausal and 64 (31.5%) pre-menopausal women were assessed for HPV-DNA. High risk HPV was detected in 7 (4.3%) and 21 (10.3%), respectively (p=0.029). Final histopathological results recorded were normal cervix, low grade cervical intra-epithelial neoplasia (CIN 1), and high grade cervical intra-epithelial neoplasia (CIN2-3). In group 1 results were 84.8%, 12.2% and 1.8%, respectively, and in group 2 were 71.9%, 23.2% and 4.9%. There were no cases of micro invasive or invasive cervical carcinoma in either group. Two cases were detected as endometrial carcinoma in the menopausal group (1.2%). Conclusions: In current study we found that preinvasive lesions were statistically significantly higher in pre-menopausal women than post-menopausal women with ASCUS. Cervicitis was more common in menopausal women. Therefore, we think that in case of ASCUS in a post-menopausal woman there is no need for radical management.

ASSESSMENT OF AORTIC ELASTICITY PROPERTIES IN PATIENTS WITH CELIAC DISEASE

Nermin Bayar,Ayhan Hilmi Çekin,Şakir Arslan,Göksel Çağırcı,Selçuk Küçükseymen,Serkan Çay,Ferda Akbay Harmandar,Bayram Yeşil 대한심장학회 2016 Korean Circulation Journal Vol.46 No.2

Background and Objectives Celiac disease (CD) is a chronic autoimmune disorder induced by dietary gluten intake by individuals who are genetically sensitive. Many studies report an increased risk of cardiovascular diseases in such patients. The aim of this study is to assess aortic elasticity properties in patients with CD that may be associated with an increased risk of cardiovascular disease. Subjects and Methods Eighty-one patients diagnosed with CD by antibody test and biopsy and 63 healthy volunteers were included in this prospective study. Electrocardiographic and echocardiographic examinations were performed. Results The CD group did not have any differences in the conventional echocardiographic parameters compared to the healthy individuals. However, patients in the CD group had an increased aortic stiffness beta index (4.3±2.3 vs. 3.6±1.6, p=0.010), increased pressure strain elastic modulus (33.6±17.0 kPa vs. 28.5±16.7 kPa, p=0.037), decreased aortic distensibility (7.0±3.0×10-6 cm2/dyn vs. 8.2±3.6×10-6 cm2/dyn, p=0.037), and similar aortic strain (17.9±7.7 vs. 16.0±5.5, p=0.070) compared to the control group. Patients with CD were found to have an elevated neutrophil/lymphocyte ratio compared to the control group (2.54±0.63 vs. 2.24±0.63, p=0.012). However, gluten-free diet and neutrophil/lymphocyte ratio were not found to be associated with aortic elasticity. Conclusion Patients with CD had increased aortic stiffness and decreased aortic distensibility. Gluten-free diet enabled the patients with CD to have a reduction in the inflammatory parameters whereas the absence of a significant difference in the elastic properties of the aorta may suggest that the risk of cardiovascular disease persists in this patient group despite a gluten-free diet.