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Citation Count: 0
Anticipatory effect of execution on observation: an approach using ExoPinch finger robot
(Tubitak Scientific & Technological Research Council Turkey, 2019) Arıkan, Kutluk Bilge; Zadeh, Hassan Gol Mohammad; Turgut, Ali Emre; Zinnuroğlu, Murat; Bayer, Gözde; Günendi, Zafer; Cengiz, Bülent; Department of Mechatronics Engineering
Background/aim: This study aims to explore the mirror neuron system (MNS) involvement using mu (8–12 Hz)/beta (15–25 Hz) bandsuppression in an action observation-execution paradigm.Materials and methods: Electrophysiological (EEG) data from 16 electrodes were recorded while 8 participants observed video clips ofa hand squeezing a spring. Specifically, the effect of anticipated execution on observation was studied. For this purpose, a fully actuatedfinger exoskeleton robot was utilized to synchronize observation and execution and to control the execution condition for the participants. Anticipatory effect was created with a randomized robot accompany session.Results: The results showed that the observational condition (with or without anticipation) interacted with hemisphere at central channels near somatosensory cortex. Additionally, we explored the response of MNS on the kinetics features of visual stimuli (hard or softspring).Conclusion: The results showed an interaction effect of kinetics features and hemisphere at frontal channels corresponding nearly tothe ventral premotor cortex area of the brain. The activation of mirror neurons in this area plays a crucial role in observational learning.Based on our results, we propose that specific type of visual stimuli can be combined with the functional abilities of the MNS in the action observation based treatment of hand motor dysfunction of stroke patients to have a positive additional impact.
Citation Count: 0
Association between monocyte to high-density lipoprotein cholesterol ratio and bicuspid\raortic valve degeneration
(Tubitak Scientific & Technological Research Council Turkey, 2020) Karaduman, Bilge Duran; Ayhan, Hüseyin; Keles, Telat; Bozkurt, Engin
Background/aim: From a pathophysiological point of view, inflammation is thought to be more dominant in bicuspid aortic valve\r(BAV) stenosis than tricuspid aortic valve (TAV) stenosis. Our study aimed to determine the association between monocyte to highdensity lipoprotein cholesterol (HDL-C) ratio (MHR), a new inflammatory marker, and the speed of progression of stenosis and\rpathophysiology of BAV stenosis.\rMaterials and methods: A total of 210 severe aortic stenosis patients (70 consecutive BAV patients, 140 matched TAV patients) were\rretrospectively enrolled in the study. Clinical and echocardiographic data and laboratory results related to our research were collected\rretrospectively from the patients’ records. MHR was measured as the ratio of the absolute monocyte count to the HDL-C value.\rResults: Seventy BAV (mean age: 72.0 ± 9.1 years, 42.9% female) and 140 TAV patients (mean age: 77.9 ± 8.3 years, 51.4% female)\rwith severe aortic stenosis were enrolled in this study. There was no difference between the two groups in terms of another baseline\rdemographic or clinic findings except age (P < 0.001). Monocyte count, hemoglobin level, mean platelet volume was significantly\rhigher, and HDL-C level was significantly lower in the BAV group, while other lipid and CBC parameters were found to be similar. In\rthe multivariate analysis, MHR (P = 0.005, 95% CI: 0.90–0.98) and, as expected, age (P = 0.001, 95% CI: 1.02–1.11) were found to be\rsignificant as the independent predictor of BAV, after adjusting for other risk factors.\rConclusion: Our study showed a significant correlation between increased MHR and BAV. MHR was determined as a significant\rindependent predictor for the speed of progression and diagnosis of severe BAV stenosis in multivariate analysis.
Citation Count: 0
Author Correction: Using urine FTIR spectra to screen autism spectrum disorder
(Nature Portfolio, 2024) Sarigul, Neslihan; Bozatli, Leyla; Kurultak, Ilhan; Korkmaz, Filiz; Physics Group
[No Abstract Available]
Citation Count: 2
Avoiding contingent incidents by quadrotors due to one or two propellers failure
(Public Library Science, 2023) Altinuc, Kemal Orcun; Khan, Muhammad Umer; Iqbal, Jamshed; Mechatronics Engineering
With the increasing impact of drones in our daily lives, safety issues have become a primary concern. In this study, a novel supervisor-based active fault-tolerant (FT) control system is presented for a rotary-wing quadrotor to maintain its pose in 3D space upon losing one or two propellers. Our approach allows the quadrotor to make controlled movements about a primary axis attached to the body-fixed frame. A multi-loop cascaded control architecture is designed to ensure robustness, stability, reference tracking, and safe landing. The altitude control is performed using a proportional-integral-derivative (PID) controller, whereas linear-quadratic-integral (LQI) and model-predictive-control (MPC) have been investigated for reduced attitude control and their performance is compared based on absolute and mean-squared error. The simulation results affirm that the quadrotor remains in a stable region, successfully performs the reference tracking, and ensures a safe landing while counteracting the effects of propeller(s) failures.
Citation Count: 44
Biocompatible Electroactive Tetra(aniline)-Conjugated Peptide Nanofibers for Neural Differentiation
(Amer Chemical Soc, 2018) Arioz, Idil; Erol, Ozlem; Bakan, Gokhan; Dikecoglu, F. Begum; Topal, Ahmet E.; Urel, Mustafa; Guler, Mustafa O.; Department of Electrical & Electronics Engineering
Peripheral nerve injuries cause devastating problems for the quality of patients' lives, and regeneration following damage to the peripheral nervous system is limited depending on the degree of the damage. Use of nanobiomaterials can provide therapeutic approaches for the treatment of peripheral nerve injuries. Electroactive biomaterials, in particular, can provide a promising cure for the regeneration of nerve defects. Here, a supramolecular electroactive nanosystem with tetra(aniline) (TA)-containing peptide nanofibers was developed and utilized for nerve regeneration. Self-assembled TA conjugated peptide nanofibers demonstrated electroactive behavior. The electroactive self-assembled peptide nanofibers formed a well-defined three-dimensional nanofiber network mimicking the extracellular matrix of the neuronal cells. Neurite outgrowth was improved on the electroactive TA nanofiber gels. The neural differentiation of PC-12 cells was more advanced on electroactive peptide nanofiber gels, and these biomaterials are promising for further use in therapeutic neural regeneration applications.
Citation Count: 21
Bioengineered Bacterial Membrane Vesicles with Multifunctional Nanoparticles as a Versatile Platform for Cancer Immunotherapy
(American Chemical Society, 2023) Liu,X.Z.; Wen,Z.J.; Li,Y.M.; Sun,W.R.; Hu,X.Q.; Zhu,J.Z.; Wang,R.
Inducing immunogenic cell death (ICD) is a critical strategy for enhancing cancer immunotherapy. However, inefficient and risky ICD inducers along with a tumor hypoxia microenvironment seriously limit the immunotherapy efficacy. Non-specific delivery is also responsible for this inefficiency. In this work, we report a drug-free bacteria-derived outer membrane vesicle (OMV)-functionalized Fe3O4-MnO2 (FMO) nanoplatform that realized neutrophil-mediated targeted delivery and photothermally enhanced cancer immunotherapy. In this system, modification of OMVs derived from Escherichia coli enhanced the accumulation of FMO NPs at the tumor tissue through neutrophil-mediated targeted delivery. The FMO NPs underwent reactive decomposition in the tumor site, generating manganese and iron ions that induced ICD and O2 that regulated the tumor hypoxia environment. Moreover, OMVs are rich in pathogen-associated pattern molecules that can overcome the tumor immunosuppressive microenvironment and effectively activate immune cells, thereby enhancing specific immune responses. Photothermal therapy (PTT) caused by MnO2 and Fe3O4 can not only indirectly stimulate systemic immunity by directly destroying tumor cells but also promote the enrichment of neutrophil-equipped nanoparticles by enhancing the inflammatory response at the tumor site. Finally, the proposed multi-modal treatment system with targeted delivery capability realized effective tumor immunotherapy to prevent tumor growth and recurrence. © 2023 American Chemical Society.
Citation Count: 0
Calcium Carbonate/Polydopamine Composite Nanoplatform Based on TGF-β Blockade for Comfortable Cancer Immunotherapy
(Amer Chemical Soc, 2024) Li, Yunmeng; Wang, Deqiang; Sun, Jian; Hao, Zhaokun; Tang, Letian; Sun, Wanru; Wang, Ranran
Cancer pain seriously reduces the quality of life of cancer patients. However, most research about cancer focuses solely on inhibiting tumor growth, neglecting the issue of cancer pain. Therefore, the development of therapeutic agents with both tumor suppression and cancer pain relief is crucial to achieve human-centered treatment. Here, the work reports curcumin (CUR) and ropivacaine (Ropi) coincorporating CaCO3/PDA nanoparticles (CaPNMCUR+Ropi) that realized efficient tumor immunotherapy and cancer pain suppression. The therapeutic efficiency and mechanism are revealed in vitro and in vivo. The results indicate that CaPNMCUR+Ropi underwent tumor microenvironment-responsive degradation and realized rapid release of calcium ions, Ropi, and CUR. The excessive intracellular calcium triggered the apoptosis of tumor cells, and the transient pain caused by the tumor injection was relieved by Ropi. Simultaneously, CUR reduced the levels of immunosuppressive factor (TGF-beta) and inflammatory factor (IL-6, IL-1 beta, and TNF-alpha) in the tumor microenvironment, thereby continuously augmenting the immune response and alleviating inflammatory pain of cancer animals. Meanwhile, the decrease of TGF-beta leads to the reduction of transient receptor potential vanilloid 1 (TRPV1) expression, thereby alleviating hyperalgesia and achieving long-lasting analgesic effects. The design of the nanosystem provides a novel idea for human-centered tumor treatment in the future.
Citation Count: 15
Characteristics and outcomes of hospitalised older patients with chronic kidney disease and COVID-19: A multicenter nationwide controlled study
(Wiley-hindawi, 2021) Ozturk, Savas; Turgutalp, Kenan; Arici, Mustafa; Gok, Mahmut; Islam, Mahmud; Altiparmak, Mehmet Riza; Ates, Kenan
Objective Older adults with co-morbidities have been reported to be at higher risk for adverse outcomes of coronavirus disease 2019 (COVID-19). The characteristics of COVID-19 in older patients and its clinical outcomes in different kidney disease groups are not well known. Methods Data were retrieved from a national multicentric database supported by Turkish Society of Nephrology, which consists of retrospectively collected data between 17 April 2020 and 31 December 2020. Hospitalised patients aged 18 years or older with confirmed COVID-19 diagnosis suffering from stage 3-5 chronic kidney disease (CKD) or on maintenance haemodialysis (HD) treatment were included in the database. Non-uraemic hospitalised patients with COVID-19 were also included as the control group. Results We included 879 patients [388 (44.1%) female, median age: 63 (IQR: 50-73) years]. The percentage of older patients in the CKD group was 68.8% (n = 188/273), in the HD group was 49.0% (n = 150/306) and in the control group was 30.4% (n = 70/300). Co-morbidities were higher in the CKD and HD groups. The rate of presentation with severe-critical disease was higher in the older CKD and HD groups (43.6%, 55.3% and 16.1%, respectively). Among older patients, the intensive care unit (ICU) admission rate was significantly higher in the CKD and HD groups than in the control group (38.8%, 37.3% and 15.7%, respectively). In-hospital mortality or death and/or ICU admission rates in the older group were significantly higher in the CKD (29.3% and 39.4%) and HD groups (26.7% and 30.1%) compared with the control group (8.6% and 17.1%). In the multivariate analysis, in-hospital mortality rates in CKD and HD groups were higher than control group [hazard ratio (HR): 4.33 (95% confidence interval [CI]: 1.53-12.26) and HR: 3.09 (95% CI: 1.04-9.17), respectively]. Conclusion Among older COVID-19 patients, in-hospital mortality is significantly higher in those with stage 3-5 CKD and on maintenance HD than older patients without CKD regardless of demographic characteristics, co-morbidities, clinical and laboratory data on admission.
Citation Count: 0
Clinic-oriented injectable smart material for the treatment of diabetic wounds: Coordinating the release of GM-CSF and VEGF
(Elsevier, 2024) Kinali, Hurmet; Kalaycioglu, Gokce Dicle; Boyacioglu, Ozge; Korkusuz, Petek; Aydogan, Nihal; Vargel, Ibrahim; Basic Sciences
Chronic wounds are often caused by diabetes and present a challenging clinical problem due to vascular problems leading to ischemia. This inhibits proper wound healing by delaying inflammatory responses and angiogenesis. To address this problem, we have developed injectable particle-loaded hydrogels which sequentially release Granulocyte-macrophage- colony-stimulating-factor (GM-CSF) and Vascular endothelial growth factor (VEGF) encapsulated in polycaprolactone-lecithin-geleol mono-diglyceride hybrid particles. GM-CSF promotes inflammation, while VEGF facilitates angiogenesis. The hybrid particles (200 -1000 nm) designed within the scope of the study can encapsulate the model proteins Bovine Serum Albumin 65 +/- 5 % and Lysozyme 77 +/- 10 % and can release stably for 21 days. In vivo tests and histological findings revealed that in the hydrogels containing GM-CSF/VEGF-loaded hybrid particles, wound depth decreased, inflammation phase increased, and fibrotic scar tissue decreased, while mature granulation tissue was formed on day 10. These findings confirm that the hybrid particles first initiate the inflammation phase by delivering GM-CSF, followed by VEGF, increasing the number of vascularization and thus increasing the healing rate of wounds. We emphasize the importance of multi-component and sequential release in wound healing and propose a unifying therapeutic strategy to sequentially deliver ligands targeting wound healing stages, which is very important in the treatment of the diabetic wounds.
Citation Count: 0
The clinical and demographical characteristics of Turkish pediatric lymphedema patients: a multicenter study
(Tubitak Scientific & Technological Research Council Turkey, 2022) Borman, Pinar; Balcan, Aysegul; Eyigor, Sibel; Coskun, Evrim; Ayhan, Figen; Cakit, Burcu Duyur; Dogan, Sevil Ceyhan
Background/aim: Reducing lymphedema-associated burden and disability in the pediatric setting requires improved awareness and understanding clinical properties of the lymphedema. The aim of this study was to evaluate the clinical and demographic characteristics of patients with pediatric lymphedema presented to different lymphedema centers in Turkey. Materials and methods: The socio-demographic and clinical characteristics of the children including age, gender, presence of genetic syndromes, duration of edema, site and stage of lymphedema and the received therapies were determined. Parental and children education on self-management techniques were recorded. Results: A total of 122 children (female: 66, male: 56) with a mean age of 120.7 +/- 71.2 months were included from 7 centers. Of them; 92% had primary, 8% had secondary lymphedema mostly due to infection and trauma. Lymphedema was part of a syndrome in 18% of the children. The most common site of involvement was the lower extremity, followed by upper extremity and genital involvement. Lymphedema was complicated in 17 % of children, mainly with a clinical picture of cellulitis, infection, and pain. The median duration of lymphedema was 41 (5-216) months. Although most of the children had stage 2 lymphedema, only 40% of them received treatment. The most commonly received treatment was compression therapy. No family or child was educated for self-care management before. Conclusion: In conclusion, pediatric lymphedema has a comparable gender distribution and usually involves the lower extremities. Although most of the children had advanced disease, more than half of the patients did not receive any treatment indicating the unmet need for management of lymphedema. The education of patients and/or children about self-management methods were lacking. We suggest educational activities for both families of children with lymphedema and health care providers, in order to facilitate early reference to lymphedema units and to receive prompt preventive and therapeutic approaches for this suffering condition.
Citation Count: 0
Clinical and Laboratory Evaluation of Acute Pericarditis Associated with Antinuclear Antibodies Positivity
(Bentham Science Publ Ltd, 2023) Dursun, Ali Dogan; Saricam, Ersin; Erdem, Hakan; Sariyildiz, Gulcin Turkmen; Ozyer, Esref Umut; Bozkurt, Engin; Cantekin, Omer Faruk; Anesthesia Program; Basic Sciences
Background Up to 30% of patients with acute pericarditis develop recurrent pericarditis. Acute pericarditis may be a manifestation of an underlying systemic autoimmune disease. Therefore, we evaluated the characteristics of patients with acute pericarditis according to antinuclear antibodies (ANA) positivity/negativity. Methods Participants with acute pericarditis and negative ANA (n=29), recurrent pericarditis with positive ANA (n=30) and healthy controls (n=11) were examined. The groups were compared using serum parameters (ANA, C-reactive protein, leucocyte count, erythrocyte sedimentation rate, total antioxidant status, nitric oxide (NO), and oxidative stress index (OSI)) and imaging techniques (electrocardiogram, echocardiography, cardiovascular magnetic resonance, and venous Doppler ultrasound). Results In females, acute pericarditis associated with ANA occurred more frequently (p<0.001). ANA-positive acute pericarditis had significantly lower NO and OSI (p<0.05 and p<0.001, respectively) and pericardial inflammation on magnetic resonance. We found a pulmonary embolism in one patient with positive ANA. Slow venous flow (SVF) occurred more often in acute pericarditis associated with ANA than in the ANA-negative group on venous ultrasound (p<0.05). The prevalence of positive ANAs was 1.6 times higher among SVF patients than in controls. Conclusion This study suggests that acute pericarditis associated with ANA is more common in middle-aged females. SVF and lower oxidative stress tests were more common in patients with ANA-associated acute pericarditis. Acute pericarditis associated with ANA could be considered as a hypercoagulable state. Therefore, all newly diagnosed pericarditis patients (especially females) should be checked for ANA positivity. Awareness of this coexistence should be promptly addressed to establish management strategies.
Citation Count: 1
Commentary on "Spectral characterization of the binding and conformational changes of serum albumins upon interaction with an anticancer drug, anastrozole"
(Pergamon-elsevier Science Ltd, 2015) Korkmaz, Filiz; Physics Group
The manuscript by R. Punith and J. Seetharamappa (http://dx.doi.org/10.1016/j.saa.201202.038) presents the interaction between serum albumin from human (HAS) and from bovine (BSA) with a drug called Anastrozole (AZ). The drug is on the market for treating patients with breast cancer after surgery and for metastasis in women. The study utilizes various spectroscopic techniques such as; fluorescence, synchronous fluorescence, 3D fluorescence measurements, FTIR, CD and UV. Although there are some relatively minor comments on the paper, the main point that needs to be reviewed by the authors is the result of FTIR measurements. Based on the data provided in the text (there is no figure), the protein sample is not in its native state, which makes the data inconvenient to be used in drawing conclusions. Authors are kindly requested to take another look at the FUR experiments. (C) 2014 Elsevier B.V. All rights reserved.
Citation Count: 0
Comparison of Amiodarone Loading Dosage in the Treatment of Postoperative Atrial Fibrillation: High Versus Standard Dose Treatment
(Bentham Science Publ Ltd, 2024) Saricam, Ersin; Ocal, Arslan; Iscanli, Murat Dogan; Bozkurt, Engin; Ilkay, Erdogan; Cantekin, Omer Faruk
Background Postoperative atrial fibrillation (POAF) is associated with poor outcomes, including hemodynamic instability, stroke, myocardial infarction, and death. In hemodynamic stable patients, the rhythm-control strategy is more advantageous than rate control. Current standard intravenous amiodarone administration has limited success and a delayed effect; the acute success rate is 44% (8-12 h to several days).Purpose The aim of this study was to evaluate the effectiveness of higher amiodarone loading dosage to restore sinus rhythm in patients with POAF after noncardiac surgery.Methods This is a prospective, randomized, controlled single-center study. The study included 39 patients with POAF, divided into group I (n=27) (intravenous 600 mg amiodarone loading dosage over 2 h and infusion of 50 mg/h over a 24-h period) and group II (n=12) (standard protocol; 300 mg of bolus intravenously in 30 min and infusion of 50 mg/h over a 24-h period). The primary endpoint of the study was a restoration of sinus rhythm at the 24th hour.Results Baseline clinical, laboratory and echocardiographic characteristics of both groups were similar. The patients with higher loading amiodarone dosage had earlier restoration of sinus rhythm (2.38 +/- 1.41 vs 8.66 +/- 2.87 h, respectively; p=0.015). There was no significant difference in achieving sinus rhythm at the 24th hour between both groups.Conclusion Higher loading amiodarone dosage increased early conversions to sinus rhythm compared with standard amiodarone protocol in patients with POAF.
Citation Count: 20
A Computationally Efficient Method for Hybrid EEG-fNIRS BCI Based on the Pearson Correlation
(Hindawi Ltd, 2020) Hasan, Mustafa A. H.; Khan, Muhammad U.; Mishra, Deepti; Computer Engineering
A hybrid brain computer interface (BCI) system considered here is a combination of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). EEG-fNIRS signals are simultaneously recorded to achieve high motor imagery task classification. This integration helps to achieve better system performance, but at the cost of an increase in system complexity and computational time. In hybrid BCI studies, channel selection is recognized as the key element that directly affects the system's performance. In this paper, we propose a novel channel selection approach using the Pearson product-moment correlation coefficient, where only highly correlated channels are selected from each hemisphere. Then, four different statistical features are extracted, and their different combinations are used for the classification through KNN and Tree classifiers. As far as we know, there is no report available that explored the Pearson product-moment correlation coefficient for hybrid EEG-fNIRS BCI channel selection. The results demonstrate that our hybrid system significantly reduces computational burden while achieving a classification accuracy with high reliability comparable to the existing literature.
Citation Count: 98
Copper(0) Nanoparticles Supported on Silica-Coated Cobalt Ferrite Magnetic Particles: Cost Effective Catalyst in the Hydrolysis of Ammonia-Borane with an Exceptional Reusability Performance
(Amer Chemical Soc, 2012) Kaya, Murat; Zahmakiran, Mehmet; Ozkar, Saim; Volkan, Murvet; Chemical Engineering
Herein we report the development of a new and cost-effective nanocomposite catalyst for the hydrolysis of ammonia-borane (NH3BH3), which is considered to be one of the most promising solid hydrogen carriers because of its high gravimetric hydrogen storage capacity (19.6% wt) and low molecular weight. The new catalyst system consisting of copper nanoparticles supported on magnetic SiO2/CoFe2O4 particles was reproducibly prepared by wet-impregnation of Cu(II) ions on SiO2/CoFe2O4 followed by in situ reduction of the Cu(II) ions on the surface of magnetic support during the hydrolysis of NH3BH3 and characterized by ICP-MS, XRD, XPS, TEM, HR-TEM and N-2 adsorption-desorption technique. Copper nanoparticles supported on silica coated cobalt(II) ferrite SiO2/CoFe2O4 (CuNPs@SCF) act as highly active catalyst in the hydrolysis of ammonia-borane, providing an initial turnover frequency of TOF = 2400 h(-1) at room temperature, which is not only higher than all the non-noble metal catalysts but also higher than the majority of the noble metal based homogeneous and heterogeneous catalysts employed in the same reaction.. More importantly, they were easily recovered by using a permanent magnet in the reactor wall and reused for up, to 10 recycles without losing their inherent catalytic activity significantly, which demonstrates the exceptional reusability of the CuNPs@SCF catalyst.
Citation Count: 0
The day the earth shook
(Springer Heidelberg, 2023) Sezer, Siren; Tuglular, Serhan; Yildiz, Alaattin
[No Abstract Available]
Citation Count: 18
The design and fabrication of supramolecular semiconductor nanowires formed by benzothienobenzothiophene (BTBT)-conjugated peptides
(Royal Soc Chemistry, 2018) Khalily, Mohammad Aref; Usta, Hakan; Ozdemir, Mehmet; Bakan, Gokhan; Dikecoglu, F. Begum; Edwards-Gayle, Charlotte; Guler, Mustafa O.; Department of Electrical & Electronics Engineering
pi-Conjugated small molecules based on a [1]benzothieno[3,2-b]benzothiophene (BTBT) unit are of great research interest in the development of solution-processable semiconducting materials owing to their excellent charge-transport characteristics. However, the BTBT -core has yet to be demonstrated in the form of electro-active one-dimensional (1D) nanowires that are self-assembled in aqueous media for potential use in bioelectronics and tissue engineering. Here we report the design, synthesis, and self-assembly of benzothienobenzothiophene (BTBT)-peptide conjugates, the BTBT-peptide (BTBT-C-3-COHN-Ahx-VVAGKK-Am) and the C-8-BTBT-peptide (C-8-BTBT-C-3-COHN-Ahx-VVAGKK-Am), as -sheet forming amphiphilic molecules, which self-assemble into highly uniform nanofibers in water with diameters of 11-13(+/- 1) nm and micron-size lengths. Spectroscopic characterization studies demonstrate the J-type - interactions among the BTBT molecules within the hydrophobic core of the self-assembled nanofibers yielding an electrical conductivity as high as 6.0 x 10(-6) S cm(-1). The BTBT -core is demonstrated, for the first time, in the formation of self-assembled peptide 1D nanostructures in aqueous media for potential use in tissue engineering, bioelectronics and (opto)electronics. The conductivity achieved here is one of the highest reported to date in a non-doped state.
Citation Count: 5
Distinguishing Intermediate and Novice Surgeons by Eye Movements
(Frontiers Media Sa, 2020) Menekse Dalveren, Gonca Gokce; Cagiltay, Nergiz Ercil; Software Engineering
Surgical skill-level assessment is key to collecting the required feedback and adapting the educational programs accordingly. Currently, these assessments for the minimal invasive surgery programs are primarily based on subjective methods, and there is no consensus on skill level classifications. One of the most detailed of these classifications categorize skill levels as beginner, novice, intermediate, sub-expert, and expert. To properly integrate skill assessment into minimal invasive surgical education programs and provide skill-based training alternatives, it is necessary to classify the skill levels in as detailed a way as possible and identify the differences between all skill levels in an objective manner. Yet, despite the existence of very encouraging results in the literature, most of the studies have been conducted to better understand the differences between novice and expert surgical skill levels leaving out the other crucial skill levels between them. Additionally, there are very limited studies by considering the eye-movement behaviors of surgical residents. To this end, the present study attempted to distinguish novice- and intermediate-level surgical residents based on their eye movements. The eye-movement data was recorded from 23 volunteer surgical residents while they were performing four computer-based simulated surgical tasks under different hand conditions. The data was analyzed using logistic regression to estimate the skill levels of both groups. The best results of the estimation revealing a 91.3% recognition rate of predicting novice and intermediate surgical residents on one scenario were selected from four under the dominant hand condition. These results show that the eye-movements can be potentially used to identify surgeons with intermediate and novice skills. However, the results also indicate that the order in which the scenarios are provided, and the design of the scenario, the tasks, and their appropriateness with the skill levels of the participants are all critical factors to be considered in improving the estimation ratio, and hence require thorough assessment for future research.
Citation Count: 4
Do preterm babies sleep differently than their peers? Sleep characteristics and their associations with maternal depression and parenting stress
(Elsevier, 2022) Akkus, Pinar Zengin; Bahtiyar-Saygan, Bahar; Department of Psychology
Objectives: The findings regarding the association between prematurity, sleep problems, and maternal psychological well-being are mixed. This study examined preterm- and term-born infants' sleep patterns, ecology, and problems, in addition to the associations of these patterns with maternal parenting stress and depressive symptomatology. Methods: In total, 84 mothers of infants between 6 and 17 months of corrected age, in which 40 were preterm infants and 44 were healthy full-term infants, participated in the study. Children's sleep was evaluated by the Brief Infant Sleep Questionnaire. Maternal depressive symptoms were screened by the Edinburgh Postnatal Depression Scale. Maternal parenting stress was measured via the Parenting Stress Index-Short Form. Results: In preterm infants, lower total and nocturnal sleep duration and later falling asleep time were identified compared to term infants. Regarding sleep ecology, the percentages of poor sleepers, mother's perception of child's and her own sleep problems were similar in both groups. While the most common method of falling asleep was 'rocking the baby' in the preterm group, it was 'breastfeeding' in the term group. In both groups, the maternal perception of sleep problems positively predicted maternal parenting stress. Lastly, compared to good sleepers, higher maternal parenting stress, higher maternal perception of mother's and child's sleep problems, and lower infants' age were identified among poor sleepers. Conclusions: Despite many similarities in the sleep characteristics of preterm and term infants, several differences in sleep patterns and sleep ecology of preterm infants were identified. Since the maternal perception of sleep problems was found to predict parenting stress, guidance on infant sleep is suggested to support families. (C) 2022 Elsevier B.V. All rights reserved.
A Drop in Serum Progesterone From Oocyte Pick-Up +3 Days To +5 Days in Fresh Blastocyst Transfer, Using Hcg-Trigger and Standard Luteal Support, Is Associated With Lower Ongoing Pregnancy Rates
(Oxford University Press, 2023) Uyanik,E.; Mumusoglu,S.; Polat,M.; Yarali Ozbek,I.; Esteves,S.C.; Humaidan,P.; Yarali,H.; First and Emergency Aid Program
STUDY QUESTION: Do early-and mid-luteal serum progesterone (P4) levels impact ongoing pregnancy rates (OPRs) in fresh blastocyst transfer cycles using standard luteal phase support (LPS)? SUMMARY ANSWER: A drop in serum P4 level from oocyte pick-up (OPU) + 3 days to OPU + 5 days (negative ΔP4) is associated with a ∼2-fold decrease in OPRs. WHAT IS KNOWN ALREADY: In fresh embryo transfer cycles, significant inter-individual variation occurs in serum P4 levels during the luteal phase, possibly due to differences in endogenous P4 production after hCG trigger and/or differences in bioavailability of exogenously administered progesterone (P) via different routes. Although exogenous P may alleviate this drop in serum P4 in fresh transfer cycles, there is a paucity of data exploring the possible impact on reproductive outcomes of a reduction in serum P4 levels. STUDY DESIGN, SIZE, DURATION: Using a prospective cohort study design, following the initial enrollment of 558 consecutive patients, 340 fulfilled the inclusion and exclusion criteria and were included in the final analysis. The inclusion criteria were: (i) female age ≤40 years, (ii) BMI ≤35 kg/m2, (iii) retrieval of ≥3 oocytes irrespective of ovarian reserve, (iv) the use of a GnRH-Agonist or GnRH-Antagonist protocol with recombinant hCG triggering (6500 IU), (v) standard LPS and (vi) fresh blastocyst transfer. The exclusion criteria were: (i) triggering with GnRH-Agonist or GnRH-Agonist plus recombinant hCG (dual trigger), (ii) circulating P4 >1.5 ng/ml on the day of trigger and (iii) cleavage stage embryo transfer. Each patient was included only once. The primary outcome was ongoing pregnancy (OP), as defined by pregnancy ≥12 weeks of gestational age. PARTICIPANTS/MATERIALS, SETTING, METHODS: A GnRH-Agonist (n = 53) or GnRH-Antagonist (n = 287) protocol was used for ovarian stimulation. Vaginal progesterone gel (Crinone, 90 mg, 8%, Merck) once daily was used for LPS. Serum P4 levels were measured in all patients on five occasions: on the day of ovulation trigger, the day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days; timing of blood sampling was standardized to be 3-5 h after the morning administration of vaginal progesterone gel. The delta P4 (ΔP4) level was calculated by subtracting the P4 level on the OPU + 3 days from the P4 level on the OPU + 5 days, resulting in either a positive or negative ΔP4. MAIN RESULTS AND THE ROLE OF CHANCE: The median P4 (min-max) on the day of triggering, day of OPU, OPU + 3 days, OPU + 5 days and OPU + 14 days were 0.83 ng/ml (0.18-1.42), 5.81 ng/ml (0.80-22.72), 80.00 ng/ml (22.91-161.05), 85.91 ng/ml (15.66-171.78) and 13.46 ng/ml (0.18-185.00), respectively. Serum P4 levels uniformly increased from the day of OPU to OPU + 3 days in all patients; however, from OPU + 3 days to OPU + 5 days, some patients had a decrease (negative ΔP4; n = 116; 34.1%), whereas others had an increase (positive ΔP4; n = 220; 64.7%), in circulating P4 levels. Although the median (min-max) P4 levels on the day of triggering, the day of OPU, and OPU + 3 days were comparable between the negative ΔP4 and positive ΔP4 groups, patients in the former group had significantly lower P4 levels on OPU + 5 days [69.67 ng/ml (15.66-150.02) versus 100.51 ng/ml (26.41-171.78); P < 0.001] and OPU + 14 days [8.28 ng/ml (0.28-157.00) versus 19.01 ng/ml (0.18-185.00), respectively; P < 0.001]. A drop in P4 level from OPU + 3 days to OPU + 5 days (negative ΔP4) was seen in approximately one-Third of patients and was associated with a significantly lower OPR when compared with positive ΔP4 counterparts [33.6% versus 49.1%, odds ratio (OR); 0.53, 95% CI; 0.33-0.84; P = 0.008]; this decrease in OPR was due to lower initial pregnancy rates rather than increased overall pregnancy loss rates. For negative ΔP4 patients, the magnitude of ΔP4 was a significant predictor of OP (adjusted AUC = 0.65; 95% CI; 0.59-0.71), with an optimum threshold of-8.73 ng/ml, sensitivity and specificity were 48.7% and 79.2%, respectively. BMI (OR; 1.128, 95% CI; 1.064-1.197) was the only significant predictor of having a negative ΔP4; the higher the BMI, the higher the risk of having a negative ΔP4. Among positive ΔP4 patients, the magnitude of ΔP4 was a weak predictor of OP (AUC = 0.56, 95% CI; 0.48-0.64). Logistic regression analysis showed that blastocyst morphology (OR; 5.686, 95% CI; 1.433-22.565; P = 0.013) and ΔP4 (OR; 1.013, 95% CI; 0.1001-1.024; P = 0.031), but not the serum P4 level on OPU + 5 days, were the independent predictors of OP. LIMITATIONS, REASONS FOR CAUTION: The physiological circadian pulsatile secretion of P4 during the mid-luteal phase is a limitation; however, blood sampling was standardized to reduce the impact of timing. WIDER IMPLICATIONS OF THE FINDINGS: Two measurements (OPU + 3 days and OPU + 5 days) of serum P4 may identify those patients with a drop in P4 (approximately one-Third of patients) associated with ∼2-fold lower OPRs. Rescuing these IVF cycles with additional P supplementation or adopting a blastocyst freeze-All policy should be tested in future randomized controlled trials. STUDY FUNDING/COMPETING INTEREST(S): None. S.C.E. declares receipt of unrestricted research grants from Merck and lecture fees from Merck and Med.E.A. P.H. has received unrestricted research grants from MSD and Merck, as well as honoraria for lectures from MSD, Merck, Gedeon-Richter, Theramex, and IBSA. H.Y. declares receipt of honorarium for lectures from Merck, IBSA and research grants from Merck and Ferring. The remaining authors declare that they have no conflict of interest. TRIAL REGISTRATION NUMBER: The study was registered at clinical trials.gov (NCT04128436). © 2022 The Author(s). Published by Oxford University Press on behalf of European Society of Human Reproduction and Embryology. All rights reserved.

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