Some properties of Cu-B4C composites manufactured by powder metallurgy

In this study, some properties of cold pressed Cu-B4C composites were investigated. Commercial copper powders with 40 µm particle size were reinforced with B4C in a 40µm particle size at ratios of 0, 1, 2, 3 wt.% for improving mechanical properties of copper used for electrical conductivity. Cu-B4C composites have been fabricated by powder metallurgy method and sintered at 700C for 2h in open atmosphere and then subjected to cold pressing following sintering process.  The presence of Cu and B4C which are dominant components in the sintered composites were confirmed by X-ray diffraction analyses technique and SEM-EDS.  Scanning electron microscope (SEM-EDS) was showed that B4C particles are distributed homogenously in the copper matrix. The relative densities of Cu and Cu-B4C composites sintered at 700°C are ranged from 97.5% to 90.19%. Microhardness of composites ranged from 80.65 to 87.5 HB and the electrical conductivity of composites changed between 90.04 %IACS and 68.87 %IACS. It was observed that cold pressed Cu - 1 wt.% B4C composites revealed promising physical properties

Automated dendritic spine tracking on 2-photon microscopic images (2-Foton mikroskopi görüntülerinde otomatik dendritik diken takibi)

The rapid and spontaneous morphological changes of dendritic spines have been an important observation to understand how information is stored in brain. Manual assessment of spine structure has been a useful tool to understand the differences between wild type (normal) and diseased cases. In order to perform a more through analysis, automatic tools need to be developed due to the immense amount of image data collected throughout the experiments. Additionally, dendritic spines are very dynamic structures and florescence microscopy contains high level of noise, blur and shift due to the optical properties. In this study, we track locations of dendritic spines in a full series of a time-lapse two photon microscopic images. To achieve this we propose a combined detection and tracking framework. For the detection we use a SIFT based algorithm, while the tracking requires a combination of registration and distance based spine matching. Experimental results show that this technique helps to track detected spines in time series even though the noise or blur deformed the image and complicated the detection

Dioxin analysis in pine honey from Turkey

The aim of the study is to determine concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (dl-PCBs) and indicator PCBs (ind-PCBs) in pine (honeydew) honey, which is endemic and popular in Turkey. Marchalina hellenica, which lives on Pinus brutia, is the main source of honeydew, and Apis mellifera L. collects the honeydew for making the pine honey. Pine honey is a very important bee product due to the export all over the world. In this study, honey samples were collected from Muğla and were researched via microscope. The quality of honey samples was determined by correlating NHE (Number of Honeydew Elements) to NTP (Number of Total Pollen) ratio and the honey, which has NHE to NTP ratio higher than 4.5 was accepted as a high density-superior quality pine honey. According to identifications, which have been made via microscope, pooled high quality pine honey sample was selected and analysed for dioxin. All the dioxin results were found lower than the European Union regulatory limits

Künt göğüs travması sonrası gelişen nefes darlığı ve karaciğer enzim yüksekliği

Son zamanlarda giderek artan taşıt kullanımı, Acil Servislere gelen araç içi trafik kazalarında artışı da beraberinde getirmiştir. Sıklıkla karşılaşılan delici olmayan göğüs yaralanmalarında akılda tutulması gereken bir diğer organ da kalptir. Özellikle bu hastalarda korda tendinea, papiller kas veya doğrudan kalp kası yırtılmaları ani ve hayatı tehdit edici acil durumlar yaratabilir. Ani gelişen ve/veya izlemde aniden kötüleşen kalp yetmezliği kliniklerinde, yeni saptanan karaciğer enzim testlerindeki yüksekliklerde ve kardiyak dinleme bulguları anormalliklerinde, öyküde delici olmayan göğüs yaralanması varsa, korda tendinea yırtılmaları ve kapak yetmezlik durumları akla gelmelidirRecently, an increased vehicle use, resulted in icreased in-vehicle traffic accidents at emergency departments. Heart is the another organ that should be kept in mind in frequently encountered blunt chest traumas. Chorda tendinea and papillary muscle ruptures even including myocardium may be life threatening emergent condition. Chorda ruptures and cardiac valve regurgitations should be kept in mind in patients with worsening heart failure symptoms, cardiac auscultatory abnormalities and elevated liver enzymes, who injured at in-vehicle acciden

Involvement of autophagy in T cell biology

Autophagy is an essential cellular pathway that sequesters various cytoplasmic components, including accumulated proteins, damaged organelles or invading microorganisms and delivers them to lysosomes for degradation. The function of autophagy has been reported in various tissues and systems, including its role in the regulation of cellular immunity. Autophagy plays a fundamental role at various stages of T cell maturation. It regulates the thymocyte selection and the generation of T cell repertoire by presenting intracellular antigens to MHC class molecules. Autophagy is crucial for metabolic regulation of T cells, and therefore supports cell survival and homeostasis, particularly in activated mature T cells. Furthermore, deletion of specific autophagy-related genes induces several immunological alterations including differentiation of activated T cells into regulatory, memory or natural killer T cells. In this review, we emphasize the impact of autophagy on T cell development, activation and differentiation, which is pivotal for the adaptive immune system

PMA functions as an autophagy inhibitor through activation of a serine threonine kinase

Serine-threonine kinases have vital roles in various signalling pathways such as proliferation, differentiation and apoptosis. Thus, they served as crucial players in health and disease including cancer. Isozymes of these families show tissue specific expression patterns and function specifically in different pathways. Autophagy is another major process in the cell which degrades long-lived, non-functional organelles and proteins to sustain the homeostasis. Moreover, as well as serine threonine kinases, autophagy was also found to relate with cancer in different stages. To date, relationship between serine-threonine protein kinases and autophagy has not been well studied. Therefore, we utilized PMA which is one of the three different activatory signals of this kinase family to activate the certain subgroup and we studied the role of these kinases on autophagy regulation

Identification of a serine-threonine kinase as a novel autophagic regulator

Phospholipid dependent Serine/Threonine kinases are shown to be involved in cellular mechanisms and disease related pathways. Upon different intracellular stimuli, these kinases are activated and functions. Several chemical analogues such as Phorbol 12-Mystrate 13-Acetate (PMA) and Ceramide were synthesized to mimic intracellular stimuli to study function of these kinases. For several of these kinases, activation is dependent on both PMA and a Calcium ionophore such as ionomycin. Strikingly, deregulation of these kinases has been identified in several cancers. Recent studies showed that autophagy, which evolutionary conserved cellular degradation mechanism to maintain homeostasis, is also involved in carcinogenesis. According to literature, there are no robust studies to show the interaction between autophagy and serine threonine kinases. Thus, in our study we focused to identify a novel Ser/Thr kinases involved in regulation of autophagy in cancer

Effect of serine/threonine kinases on autophagy mechanism

Autophagy is a degradation pathway, activating under stress conditions. It digests macromolecules, such as abnormal proteins and long-lived organelles by engulfing them and by subsequent delivery of the cargo to lysosomes. The members of the phospholipid-dependent serine/threonine kinases, involved in many signaling pathways, which are necessary for the regulation of cellular metabolic activation. Previous studies implicate that, serine/threonine kinases have crucial roles in the mechanism of many diseases depend on the activated and/or inactivated signaling pathway. Data indicates, the signaling pathways activated by serine/threonine kinases are also involved in activation of autophagy mechanism. However, the information about the effect of serine/threonine kinases on autophagy mechanism and the roles of these effects in disease formation is limited. In this study, we investigated the effect of activated serine/threonine kinases on autophagic pathway. We performed a commonly used autophagy technique, GFP-LC3 dot formation and by using microscopy analyses, we evaluated promotion and/or inhibition of autophagy in serine/threonine kinase-overexpressed fibroblasts as well as cancer cells. In addition, we carried out confocal microscopy analyses and examined autophagic flux by utilizing the differential pH sensitivities of RFP and GFP in mRFP-GFP-LC3 probe. Based on the shRNA-library based screening, we identified autophagy-related proteins affected by serine/threonine kinases. We further studied the involvement of serine/threonine kinases on the molecular mechanism of newly identified autophagy proteins and found that, autophagic pathway is indirectly controlled by serine/threonine kinases via specific autophagic proteins. Our data indicate the molecular connection between two critical cellular mechanisms, which have important roles in the formation of many disease pathologies, particularly cancer