Biruni University Institutional Repository
Not a member yet
2908 research outputs found
Sort by
Synthesis, Biological Evaluation and Docking Studies of Ring-Opened Analogues of Ipomoeassin F
Get PDFThe plant-derived macrocyclic resin glycoside ipomoeassin F (Ipom-F) binds to Sec61α and significantly disrupts multiple aspects of Sec61-mediated protein biogenesis at the endoplasmic reticulum, ultimately leading to cell death. However, extensive assessment of Ipom-F as a molecular tool and a therapeutic lead is hampered by its limited production scale, largely caused by intramolecular assembly of the macrocyclic ring. Here, using in vitro and/or in cellula biological assays to explore the first series of ring-opened analogues for the ipomoeassins, and indeed all resin glycosides, we provide clear evidence that macrocyclic integrity is not required for the cytotoxic inhibition of Sec61-dependent protein translocation by Ipom-F. Furthermore, our modeling suggests that open-chain analogues of Ipom-F can interact with multiple sites on the Sec61α subunit, most likely located at a previously identified binding site for mycolactone and/or the so-called lateral gate. Subsequent in silico-aided design led to the discovery of the stereochemically simplified analogue 3 as a potent, alternative lead compound that could be synthesized much more efficiently than Ipom-F and will accelerate future ipomoeassin research in chemical biology and drug discovery. Our work may also inspire further exploration of ring-opened analogues of other resin glycosides
Evaluation of the effect of different abutment materials on the final color of the restoration after aging: an ın vitro study
No full textAbstract
To compare the effect of thermomechanical aging on implant abutment color change when using different abutment backgrounds. Materials and Methods: In this study, three separate experimental groups (n = 10) with different implant abutment materials were used: zirconia, modified polyether ether ketone (MPEEK), and polyether ketone ketone (PEKK). Equal-sized glass-ceramic incisor crowns were cemented to the abutments using transparent dual-curing resin cement. The specimens were then subjected to the thermomechanical aging process for the clinical equivalent of 5 years of use. The color values of each specimen in the middle third and the incisal third were recorded by a digital spectrophotometer in the CIE L*a*b* color coordinates both before and after the aging process. Color differences between groups were compared using one-way analysis of variance (ANOVA), while Tukey test was used to compare differences within the groups (P = .05). Results: In terms of color change (Delta E00) values, the zirconia group was found to show statistically more color changes only in the middle third (P < .000), but there was no significant difference between the the MPEEK and PEKK groups. In all groups, the Delta E00 value was clinically acceptable (Delta E00 < 1.8). Conclusion: After the aging process, high-performance polymer abutments caused less color change than zirconia. Therefore, esthetically satisfying results can be obtained in the anterior region, especially when highly translucent crown materials are used
Teacher education in Turkey in the covid-19 pandemic: Experiences of the pre-service teachers about the online teaching practice
Get PDFThe aim of the study is to analyse the experience of the pre-service teachers about teaching practice courses delivered through distance education during the Covid-19 process. The study is designed as an interpretive research. The participants of the study were selected through the convenience sampling technique. The participants are 72 pre-service teachers attending the pedagogical formation program at Afyon Kocatepe University during the academic year 2020-2021. The data of the study were collected using a questionnaired with seven open-ended items which was developed by the authors. The data collected were examined through the descriptive analysis. The findings of the study indicate that pre-service teachers define distance education educationally and spatially as the teaching practice course given through distance education. They stated that they improved themselves in terms of professional and technological environment and that they liked the feature of screen sharing in the process. They also added that they mostly used the question-answer method in the course. In addition, it is found that teachers should include further methods to ensure active participation of students during the online courses. The participants reported some problems mostly caused by the students, and they offered various suggestions for the solution of these problems
Lump collision phenomena to a nonlinear physical model in coastal engineering
Get PDFAbstract: In this study, a dimensionally nonlinear evolution equation, which is the integrable shallow water wave-like equation, is investigated utilizing the Hirota bilinear approach. Lump solutions are achieved by its bilinear form and are essential solutions to various kind of nonlinear equations. It has not yet been explored due to its vital physical significant in various field of nonlinear science. In order to establish some more interaction solutions with some novel physical features, we establish collision aspects between lumps and other solutions by using trigonometric, hyperbolic, and exponential functions. The obtained novel types of results for the governing equation includes lump-periodic, two wave, and breather wave solutions. Meanwhile, the figures for these results are graphed. The propagation features of the derived results are depicted. The results reveal that the appropriate physical quantities and attributes of nonlinear waves are related to the parameter values
Evaluation of the optimal duration for retrograde intrarenal stone surgery to prevent postoperative complications
No full textAbstract Objective: To evaluate retrograde intrarenal surgery (RIRS) outcomes and to determine the effect of operative time on complications of RIRS. Methods: Patients undergoing RIRS for renal stones were evaluated. These patients were divided into two groups according to the operation time (Group 1[removed]60 minutes). Peroperative outcomes such as fluoroscopy time, stone-free rates, complications and duration of hospitalization were compared. Results: Group 1 consisted of 264 patients and Group 2 consisted of 297 patients. SFR rates, duration of hospitalization, and postoperative urinary tract infection rates were similar in both groups. Fluoroscopy time was 7.8±7.3 (0-49) sec in group 1 and 13.1±9.8 (0-81) sec in group 2. Complications according to modified Clavien–Dindo classification system (MCDCS) were 13 and 32 patients (Grade 1), 31 and 63 patients (Grade 2), 1 and 1 patient (Grade 3) in group 1 and 2, respectively. There was statistical difference between the two groups in terms of duration of fluoroscopy time and the MCDCS. Although duration of hospitalization and UTI rates were higher in group 2, no statistical significance was observed among groups. Conclusion: Limiting the operation time to 60 minutes in RIRS seems to be important in reducing postoperative complications
Synthesis and characterization of novel ssDNA X-aptamers targeting growth hormone releasing hormone (GHRH)
Get PDFBackground Growth Hormone Releasing Hormone (GHRH), 44 amino acids containing hypothalamic hormone, retains the biological activity by its first 29 amino acids. GHRH (NH2 1-29) peptide antagonists inhibit the growth of prostate, breast, ovarian, renal, gastric, pancreatic cancer in vitro and in vivo. Aptamers, single-strand RNA, or DNA oligonucleotides are capable of binding to target molecules with high affinity. Our aim in this study is to synthesize and select X-aptamers against both GHRH NH2 (1-29) and GHRH NH2 (1-44) and demonstrate synthesized aptamers' target binding activity as well as serum stability. Methods and results Aptamers against GHRH NH2 (1-44) and NH2 (1-29) peptides were synthesized, and binding affinity (Kd) of 24 putative X-aptamers was determined by the dot-blot method, co-immunofluorescence staining and, SPR analysis. The serum stability of TKY.T1.08, TKY1.T1.13, TKY.T2.08, TKY.T2.09 X-aptamers was 90-120 h, respectively. The dose-dependent binding of TKY1.T1.13, TKY.T2.08, TKY.T2.09 X-aptamers on GHRHR in MIA PaCa-2 was approved by co-IF assay results. Moreover, SPR analysis indicated the Kd (4.75, 1.21, and 4.0 nM) levels of TKY2.T1.13, TKY.T2.08, TKY.T2.09 putative X-aptamers, respectively. Conclusion Our results illustrate the synthesis of 24 putative X-aptamers against both GHRH NH2 (1- 44) and NH2 (1-29) peptides and TKY1.T1.13, TKY.T2.08, TKY.T2.09 X-aptamers have high serum stability, high target binding potential with low Kd levels
Corrosion, ion release, and surface hardness of Ti-6Al-4V and cobalt-chromium alloys produced by CAD-CAM milling and laser sintering
Get PDFAbstract Statement of problem: How the corrosion properties of cobalt-chromium (Co-Cr) and Ti (Ti-6Al-4V) alloys, frequently used in dental prostheses, are affected by different production methods is unclear. Purpose: The purpose of this in vitro study was to compare Co-Cr and Ti-6Al-4V alloys produced by computer-aided design and computer-aided manufacturing (CAD-CAM) milling or laser sintering in terms of corrosion, ion release, and surface hardness. Material and methods: Co-Cr and Ti-6Al-4V specimens were produced by CAD-CAM milling and direct metal laser sintering/selective laser sintering techniques. Testing included Vickers hardness and then open circuit potential (OCP), Tafel extrapolation, and static immersion to determine the corrosion behavior. The study used an inductively coupled plasma mass spectrometer to measure ion release. The data were analyzed by using the Kruskal-Wallis and Mann-Whitney U tests, with Bonferroni correction (α=.05). Results: The Ti-6Al-4V laser-sintered group showed the highest Vickers hardness value (P<.008), the lowest OCP value (P<.008), and the lowest corrosion potential (Vcorr) value (P<.008). The corrosion current density (Icorr) level of the Co-Cr CAD-CAM milling group was statistically significantly lower than that of the Ti-6Al-4V CAD-CAM milling and the Ti-6Al-4V laser-sintered groups (P<.008). The highest weight change was observed in the Ti-6Al-4V laser-sintered group. The Co, Cr, and Ti ion emissions were higher in specimens produced by laser sintering (P[removed].05). Conclusions: Ti-6Al-4V alloys may be a good alternative for patients with Co-Cr allergies, but as per the results of this study, Co-Cr still seems more suitable for clinical use
Does tacrolimus use have a sexual dysfunctional effect in women after renal transplant?
Get PDFBackground. Tacrolimus, one of the immunosuppressive agents, is used to prevent tissue rejection in renal transplant recipients, but the relationship between the plasma concentrations of tacrolimus and female sexual dysfunction has not yet been elucidated. The aim of this study was to determine the effect of tacrolimus use on sexual dysfunction of women after renal transplant. Methods. Twenty-one female patients who successfully underwent transplant and were treated with tacrolimus were enrolled as the patient group, while 21 patients presented to the obstetrics and gynecology clinic for different reasons were included in the study as the control group. The Beck Depression Inventory, Beck Anxiety Inventory, and Female Sexual Function Index were applied. Plasma concentrations of tacrolimus were simultaneously measured in transplant recipients. Results. The scores of all scales did not differ among groups in terms of depression, anxiety, and sexual dysfunction. All transplant recipients had a plasma concentration of tacrolimus in the range of 3 to 7 ng/L. When the patients were compared by the scores of depression and anxiety scales, the drug levels showed no effect on the depression, anxiety, and female sexual functions. Conclusions. Sexual dysfunction appears to be ameliorated in women because of the hormone levels after renal transplant at the end of the dialysis process, hence enhancing the quality of life. Normal plasma levels of tacrolimus, which is known to cause sexual dysfunction, could not change this result
Evaluation of foreign language teachers' opinions on foreign language education of children with different developments
No full textDanışman: Doç. Dr. Adeviye Tuğba TuncerÖzel gereksinimli bireyler kaynaştırma uygulamaları boyunca yaşıtlarıyla birlikte aynı müfredata dayalı eğitim almaktadırlar. Dolayısıyla bu bireylerin aldıkları eğitim içerisinde Türkçe, Matematik, Fen ve Teknoloji, Müzik, Görsel Sanatlar, Yabancı Dil, vb. dersleri bulunmaktadır ve bireyselleştirilmiş eğitim planları olsa bile bazı derslere katılmakta zorlanabilmektedir. Yabancı dil dersleri sözcük ve kavram öğretiminin oldukça yoğun olduğu dersler olduğu için kaynaştırma öğrencileri ekstra destek ihtiyaç duyabilir. Literatür taramasında kaynaştırma ve BEP hazırlığı ile ilgili farklı disiplinlerde çok sayıda araştırmalara rastlanmaktadır ancak yabancı dil eğitiminin kaynaştırma uygulamaları ile ilgili oldukça büyük bir araştırma eksiği bulunduğu görülmektedir. Bu çalışmada yabancı dil öğretmenlerinin yabancı dil derslerinde kaynaştırma uygulamalarının kullanımına yönelik görüş ve önerileri incelenmiştir. Olgubilim deseninin kullanıldığı araştırmada devlet okulu ve özel okullarda çalışan yabancı dil öğretmenlerine yarı yapılandırılmış görüşme soruları yöneltilmiş, görüşmeler sonucunda elde edilen sonuçlar betimsel analiz tekniği kullanılarak analiz edilmiştir. Yapılan analiz sonucunda elde edilen veriler doğrultusunda yabancı dil öğretmenlerine ve kaynaştırma öğrencilerine daha fazla destek olabilmek adına önerilerde bulunulmuştur.Individuals with special needs receive education based on the same curriculum with their peers during inclusion practices. The education these individuals receive includes Turkish, Mathematics, Science and Technology, Music, Visual Arts, Foreign Language courses. Even if there are individualized education plans, these individuals may find it difficult to attend some classes. Inclusion students may need extra support as the teaching of vocabulary and concepts in foreign language lessons is quite intense. In the literature review, there are many studies in different disciplines related to inclusion and IEP preparation, but it is seen that there is a great lack of research on inclusion practices in foreign language education. In this study, the views and suggestions of foreign language teachers on the use of inclusion practices in foreign language lessons were examined. In the study, in which the phenomenological design was used, semi-structured interview questions were asked to foreign language teachers working in public and private schools, and the results obtained from the interviews were analyzed using descriptive analysis technique. In line with the data obtained as a result of the analysis, suggestions were made in order to support foreign language teachers and inclusion students
Medroxyprogesterone acetate for abnormal uterine bleeding due to ovulatory dysfunction: The effect of 2 different-duration regimens
Get PDFBackground: Abnormal uterine bleeding (AUB) lowers the quality of life of women. This study attempted to determine which treatment protocol of medroxyprogesterone acetate (MPA), 15 vs 10 day-administration in a luteal phase, provides better outcomes in women with ovulatory dysfunction-related AUB (AUB-O). Material/Methods: The study included a total of 52 patients with AUB-O: Women in Group A were given MPA between days 11 and 25 of the menstrual cycle (15-day protocol), whereas women in Group B were given MPA between days 16 and 25 (10-day protocol). Outcomes were compared between the 2 groups. Results: Women in group B, compared with those in group A, more often showed regular menstrual cycles and decrement of AUB. In group B, 3 cycles of treatment were sufficient to achieve AUB-stop (p<0.05). Post-treatment hemogram parameters and surgical treatment requirements were not different between the 2 groups. Conclusions: In the second half of the cycle/predicted luteal phase, 10-day cyclic use of MPA (the group B) better regulated the menstrual cycle and more frequently stopped AUB-O