NLRC4 Inflammasome-Mediated Regulation of Eosinophilic Functions

Akkaya Ilgin,Oylumlu Ece,Ozel Irem,Uzel Goksu,Durmus Lubeyne,Ciraci Ceren 대한면역학회 2021 Immune Network Vol.21 No.6

Eosinophils play critical roles in the maintenance of homeostasis in innate and adaptive immunity. Although primarily known for their roles in parasitic infections and the development of Th2 cell responses, eosinophils also play complex roles in other immune responses ranging from anti-inflammation to defense against viral and bacterial infections. However, the contributions of pattern recognition receptors in general, and NOD-like receptors (NLRs) in particular, to eosinophil involvement in these immune responses remain relatively underappreciated. Our in vivo studies demonstrated that NLRC4 deficient mice had a decreased number of eosinophils and impaired Th2 responses after induction of an allergic airway disease model. Our in vitro data, utilizing human eosinophilic EoL-1 cells, suggested that TLR2 induction markedly induced pro-inflammatory responses and inflammasome forming NLRC4 and NLRP3. Moreover, activation by their specific ligands resulted in caspase-1 cleavage and mature IL-1β secretion. Interestingly, Th2 responses such as secretion of IL-5 and IL-13 decreased after transfection of EoL-1 cells with short interfering RNAs targeting human NLRC4. Specific induction of NLRC4 with PAM3CSK4 and flagellin upregulated the expression of IL-5 receptor and expression of Fc epsilon receptors (FcεR1α, FcεR2). Strikingly, activation of the NLRC4 inflammasome also promoted expression of the costimulatory receptor CD80 as well as expression of immunoregulatory receptors PD-L1 and Siglec-8. Concomitant with NLRC4 upregulation, we found an increase in expression and activation of matrix metalloproteinase (MMP)-9, but not MMP-2. Collectively, our results present new potential roles of NLRC4 in mediating a variety of eosinopilic functions.

Effect of Receptor Density and Size on Signal Reception in Molecular Communication via Diffusion With an Absorbing Receiver

Akkaya, Ali,Yilmaz, H. Birkan,Chan-Byoung Chae,Tugcu, Tuna IEEE 2015 IEEE COMMUNICATIONS LETTERS Vol.19 No.2

<P>The performance of molecular communication is significantly impacted by the reception process of the messenger molecules. The receptors' size and density, however, have yet to be investigated. In this letter, we analyze the effect of receptor density and size on the signal reception of an absorbing receiver with receptors. The results show that, when the total receptor area is the same, better hitting probability is achieved by using a higher number of relatively small receptors. In addition, deploying receptors, which cover a small percentage of the receiver surface, is able to create an effective communication channel that has a detectable signal level.</P>

Ultrasound-guided femoral and sciatic nerve blocks combined with sedoanalgesia versus spinal anesthesia in total knee arthroplasty

Akcan Akkaya,Umit Yasar Tekelioglu,Abdullah Demirhan,Kutay Engin Ozturan,Hakan Bayir,Hasan Kocoglu,Murat Bilgi 대한마취통증의학회 2014 Korean Journal of Anesthesiology Vol.67 No.2

Background: Although regional anesthesia is the first choice for patients undergoing total knee arthroplasty (TKA), it may not be effective and the risk of complications is greater in patients who are obese or who have spinal deformities. We compared the success of ultrasound-guided femoral and sciatic nerve blocks with sedoanalgesia versus spinal anesthesia in unilateral TKA patients in whom spinal anesthesia was difficult. Methods: We enrolled 30 patients; 15 for whom spinal anesthesia was expected to be difficult were classified as the block group, and 15 received spinal anesthesia. Regional anesthesia was achieved with bupivacaine 62.5 mg and prilocaine 250 mg to the sciatic nerve, and bupivacaine 37.5 mg and prilocaine 150 mg to the femoral nerve. Bupivacaine 20 mg was administered to induce spinal anesthesia. Hemodynamic parameters, pain and sedation scores, and surgical and patient satisfaction were compared. Results: A sufficient block could not be obtained in three patients in the block group. The arterial pressure was significantly lower in the spinal group (P < 0.001), and the incidence of nausea was higher (P = 0.017) in this group. Saturation and patient satisfaction were lower in the block group (P < 0.028), while the numerical pain score (P < 0.046) and the Ramsay sedation score were higher (P = 0.007). Conclusions: Ultrasound-guided sciatic and femoral nerve blocks combined with sedoanalgesia were an alternative anesthesia method in selected TKA patients.

The Effects of Triton X-100 and Tween 80 Surfactants on the Thermal Performance of a Nano-Lubricant: An Experimental Study

Mustafa Akkaya,Tayfun Menlik,Adnan Sözen,Metin Gürü 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.3

In this experimental study, experiments were carried out using a nano-lubricant consisting of polyol ester (POE)—titanium dioxide (TiO2)—surfactant instead of POE oil used in the compressor in a refrigeration system cycle test apparatus. The main aim of the study was to provide more efficient operation of the refrigeration system. Triton X100 (TX-100) and sorbitan polyoxyethylene monooleate (Tween 80) were used as the surface-active material. Nano-lubricants were formed by mixing TiO2 nanoparticles with POE oil at different concentrations. At these different nanoparticle concentrations, 0.5% of the surfactant was used. The reason for using a surfactant in the nano-lubricant was to prevent agglomeration in the mixture. TX-100 and Tween 80 surfactants were also used to study the effects of the surfactant on the nano-lubricant. Experiments were carried out using three different concentrations and three measurements for each concentration using the POE/TiO2/surfactant nano-lubricants. The best improvement was achieved when a nano-lubricant consisting of a mixture of TX-100 and POE oil with a concentration of 1.5% TiO2 was used. The improvement in coefficient of performance (COP) for the refrigeration cycle was 39.42%.

Tibial Base Plate for Total Knee Arthroplasty: Symmetric or Asymmetric?

Murat Bozkurt,Mustafa Akkaya,Mesut Tahta,Safa Gursoy,Ahmet Firat 대한정형외과학회 2017 Clinics in Orthopedic Surgery Vol.9 No.3

Background: Ideal positioning and best coverage of the tibial base plate are essential in total knee arthroplasty. There are 2 types of tibial base plates: symmetric and asymmetric. The superiority of one to the other is still controversial. The aim of this study was to compare symmetric and asymmetric tibial base plates for total knee arthroplasty in terms of rotational alignment and coverage. Methods: The study was conducted on a total of 80 cadaveric tibial bones. Two surgeons were asked to place 20 symmetric (group 1) and 20 asymmetric (group 2) tibial base plates taking care to ensure the best coverage that they were able to determine. Afterwards, the rotational errors and coverage were assessed with reference to the posterior tibial margin and posterior condylar axis on the three-dimensional computed tomography (3D CT) scan. In the second part of the study, the surgeons were asked to place 20 symmetric (group 3) and 20 asymmetric (group 4) base plates taking care to ensure the best rotational alignment. The rotational errors and the areas uncovered or overstuffed after the application were measured on the 3D CT scan. Results: On the comparison of rotational errors, while there was no significant difference between group 1 and group 2 in terms of coverage (p = 0.624), the mean external rotation error was significantly greater in group 2 (p = 0.034). On the comparison of coverage, while there was no significant difference between group 3 and group 4 in terms of rotation (p = 0.36), the mean ratios of the uncovered tibial surface to the total tibial surface (p = 0.041) and also the overstuffed area to the total base plate surface (p = 0.029) were significantly greater in group 4. Conclusions: The determination of correct size and rotation of the tibial component is essential for favorable outcomes of total knee arthroplasty. In this study, the symmetric tibial base plate design was more effective than the asymmetric design in providing the ideal tibial rotation and coverage.

Static Worst-Case Energy and Lifetime Estimation of Wireless Sensor Networks

Liu, Yu,Zhang, Wei,Akkaya, Kemal Korean Institute of Information Scientists and Eng 2010 Journal of Computing Science and Engineering Vol.4 No.2

With the advance of computer and communication technologies, wireless sensor networks (WSNs) are increasingly used in many aspects of our daily life. However, since the battery lifetime of WSN nodes is restricted, the WSN lifetime is also limited. Therefore, it is crucial to determine this limited lifetime in advance for preventing service interruptions in critical applications. This paper proposes a feasible static analysis approach to estimating the worstcase lifetime of a WSN. Assuming known routes with a given sensor network topology and SMAC as the underlying MAC protocol, we statically estimate the lifetime of each sensor node with a fixed initial energy budget. These estimations are then compared with the results obtained through simulation which run with the same energy budget on each node. Experimental results of our research on TinyOS applications indicate that our approach can safely and accurately estimate worst-case lifetime of the WSN. To the best of our knowledge, our work is the first one to estimate the worst-case lifetime of WSNs through a static analysis method.

The Crystal Field Effects in the Spin-1 ising Model with FM/AFM Interactions on a Two-layer Bethe Lattice

Erhan Albayrak,Seyma Akkaya 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.4

The exact recursion equations in a pair-wise approach are used to study the phase transitions on a two-layer Bethe lattice with crystal field (D) and external magnetic field (H) acting on the layers. The ferromagnetic (FM) and the antiferromagnetic (AFM) interactions for the spins of the upper and the lower layers, respectively, and either a FM- or an AFM-type interaction between the adjacent spins of the layers are assumed. The ground state (GS) phase diagrams of the model are calculated on the (J2/J1, J3/qJ1) planes for given system parameters, and thirteen distinct GS configurations are obtained. With the GS phase diagrams, the temperature-dependent phase diagrams of the model are obtained by studying the thermal behaviors of the order parameters and the response functions. The model was found to exhibit first- and second-order phase transitions for the coordination numbers q = 3, 4, and 6; hence, tricritical points are also observed. A reentrant behavior is also found whenever the model displays two N´eel temperatures. The exact recursion equations in a pair-wise approach are used to study the phase transitions on a two-layer Bethe lattice with crystal field (D) and external magnetic field (H) acting on the layers. The ferromagnetic (FM) and the antiferromagnetic (AFM) interactions for the spins of the upper and the lower layers, respectively, and either a FM- or an AFM-type interaction between the adjacent spins of the layers are assumed. The ground state (GS) phase diagrams of the model are calculated on the (J2/J1, J3/qJ1) planes for given system parameters, and thirteen distinct GS configurations are obtained. With the GS phase diagrams, the temperature-dependent phase diagrams of the model are obtained by studying the thermal behaviors of the order parameters and the response functions. The model was found to exhibit first- and second-order phase transitions for the coordination numbers q = 3, 4, and 6; hence, tricritical points are also observed. A reentrant behavior is also found whenever the model displays two N´eel temperatures.

Primary Leiomyosarcoma of the Breast: A Case Report

Zülfikar Karabulut,Hampar Akkaya,Gökhan Moray 한국유방암학회 2012 Journal of breast cancer Vol.15 No.1

Primary leiomyosarcoma of the breast is an extremely rare tumor, accounting for less than 1% of all breast tumors and only 24 cases have been reported in the English medical journals. It is quite difficult to diagnose leiomyosarcoma preoperatively. Establishing an accurate diagnosis is very important in planning treatment. When preoperative diagnosis can be achieved before or during the operation, wide resection should be performed. There is no need for axillary lymph node dissection. In this case report, we present a case involving primary leiomysarcoma of the breast in a 48-year-old woman and we discuss optimal treatment options.

Impact of Jet-Grouting Pressure on the Strength and Deformation Characteristics of Sandy and Clayey Soils in the Compression Zone

Mutluhan Akin,İsmail Akkaya,Müge K. Akin,Ali Özvan,Yusuf Ak 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.8

Jet-grouting as a soil improvement method is extensively preferred in today’s civil engineering practice. High-modulus grout columns constructed by extremely high jetting pressures displace the surrounding soil causing a densification in soil particles. Accordingly, the strength as well as the deformation characteristics of subsurface soils are relatively improved across the compression zone which is under the influence of high jetting pressure. In this study, the modification of soil properties in compression zone after jetgrouting in sandy and clayey soils is investigated by standard penetration tests (SPT) and multi-channel analysis of surface waves (MASW) performed at a couple of construction sites along established jet-grout column rows. The in-situ test results point out significant improvement of the measured parameters compared to initial values. The rate of enhancement in the compression zone is higher in sandy strata than that of clayey deposits. The strengthening of soil due to jetting pressure is validated by finite element analyses as well. Furthermore, very low shear strain values are obtained in clayey soils with respect to the improved characteristics of compression zone representing extremely low shear deformation under foundation.

Is the diagnosis of calcified laryngeal cartilages on panoramic radiographs possible?

Cagirankaya, Leyla Berna,Akkaya, Nursel,Akcicek, Gokcen,Dogru, Hatice Boyacioglu Korean Academy of Oral and Maxillofacial Radiology 2018 Imaging Science in Dentistry Vol.48 No.2

Purpose: Detecting laryngeal cartilages (triticeous and thyroid cartilages) on panoramic radiographs is important because they may be confused with carotid artery calcifications in the bifurcation region, which are a risk factor for stroke. This study assessed the efficiency of panoramic radiography in the diagnosis of calcified laryngeal cartilages using cone-beam computed tomography (CBCT) as the reference standard. Materials and Methods: A total of 312 regions(142 bilateral, 10 left, 18 right) in 170 patients(140 males, 30 females) were examined. Panoramic radiographs were examined by an oral and maxillofacial radiologist with 11 years of experience. CBCT scans were reviewed by 2 other oral and maxillofacial radiologists. The kappa coefficient(${\kappa}$) was calculated to determine the level of intra-observer agreement and to determine the level of agreement between the 2 methods. Diagnostic indicators(sensitivity, specificity, accuracy, and false positive and false negative rates) were also calculated. P values <.05 were considered to indicate statistical significance. Results: Eighty-two images were re-examined to determine the intra-observer agreement level, and the kappa coefficient was calculated as 0.709 (P<.05). Statistically significant and acceptable agreement was found between the panoramic and CBCT images (${\kappa}=0.684$ and P<.05). The sensitivity, specificity, diagnostic accuracy rate, the false positive rate, and the false negative rate of the panoramic radiographs were 85.4%, 83.5%, 84.6%, 16.5%, and 14.6%, respectively. Conclusion: In most cases, calcified laryngeal cartilages could be diagnosed on panoramic radiographs. However, due to variation in the calcifications, diagnosis may be difficult.