Search results for: carragenan induced edema
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2866

Search results for: carragenan induced edema

1636 Effects of Coastal Structure Construction on Ecosystem

Authors: Afshin Jahangirzadeh, Shatirah Akib, Keyvan Kimiaei, Hossein Basser

Abstract:

Coastal defense structures were built to protect part of shore from beach erosion and flooding by sea water. Effects of coastal defense structures can be negative or positive. Some of the effects are beneficial in socioeconomic aspect, but environment matters should be given more concerns because it can bring bad consequences to the earth landscape and make the ecosystem be unbalanced. This study concerns on the negative impacts as they are dominant. Coastal structures can extremely impact the shoreline configuration. Artificial structures can influence sediment transport, split the coastal space, etc. This can result in habitats loss and lead to noise and visual disturbance of birds. There are two types of coastal defense structures, hard coastal structure and soft coastal structure. Both coastal structures have their own impacts. The impacts are induced during the construction, maintaining, and operation of the structures.

Keywords: ecosystem, environmental impact, hard coastal structures, soft coastal structures

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1635 EEG Signal Processing Methods to Differentiate Mental States

Authors: Sun H. Hwang, Young E. Lee, Yunhan Ga, Gilwon Yoon

Abstract:

EEG is a very complex signal with noises and other bio-potential interferences. EOG is the most distinct interfering signal when EEG signals are measured and analyzed. It is very important how to process raw EEG signals in order to obtain useful information. In this study, the EEG signal processing techniques such as EOG filtering and outlier removal were examined to minimize unwanted EOG signals and other noises. The two different mental states of resting and focusing were examined through EEG analysis. A focused state was induced by letting subjects to watch a red dot on the white screen. EEG data for 32 healthy subjects were measured. EEG data after 60-Hz notch filtering were processed by a commercially available EOG filtering and our presented algorithm based on the removal of outliers. The ratio of beta wave to theta wave was used as a parameter for determining the degree of focusing. The results show that our algorithm was more appropriate than the existing EOG filtering.

Keywords: EEG, focus, mental state, outlier, signal processing

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1634 Structure and Morphology of Electrodeposited Nickel Nanowires at an Electrode Distance of 20mm

Authors: Mahendran Samykano, Ram Mohan, Shyam Aravamudhan

Abstract:

The objective of this work is to study the effect of two key factors-external magnetic field and applied current density during the template-based electrodeposition of nickel nanowires using an electrode distance of 20 mm. Morphology, length, crystallite size, and crystallographic characterization of the grown nickel nanowires at an electrode distance of 20mm are presented. For this electrode distance of 20 mm, these two key electrodeposition factors when coupled was found to reduce crystallite size with a higher growth length and preferred orientation of Ni crystals. These observed changes can be inferred to be due to coupled interaction forces induced by the intensity of applied electric field (current density) and external magnetic field known as magnetohydrodynamic (MHD) effect during the electrodeposition process.

Keywords: anodic alumina oxide, electrodeposition, nanowires, nickel

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1633 Aftershock Collapse Capacity Assessment of Mid-Rise Steel Moment Frames Subjected to As-Recorded Mainshock-Aftershock

Authors: Mohammadmehdi Torfehnejada, Serhan Senso

Abstract:

Aftershock collapse capacity of Special Steel Moment Frames (SSMFs) is evaluated under aftershock earthquakes by considering building heights 8 and 12 stories. The assessment evaluates the residual collapse capacity under aftershock excitation when various levels of damage have been induced by the mainshock. For this purpose, incremental dynamic analysis (IDA) under aftershock follows the mainshock imposing the intended damage level. The study results indicate that aftershock collapse capacity of this structure may decrease remarkably when the structure is subjected to large mainshock damage. The capacity reduction under aftershock is finally related to the mainshock damage level through regression equations.

Keywords: aftershock collapse capacity, special steel moment frames, mainshock-aftershock sequences, incremental dynamic analysis, mainshock damage

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1632 Analyzing Concrete Structures by Using Laser Induced Breakdown Spectroscopy

Authors: Nina Sankat, Gerd Wilsch, Cassian Gottlieb, Steven Millar, Tobias Guenther

Abstract:

Laser-Induced Breakdown Spectroscopy (LIBS) is a combination of laser ablation and optical emission spectroscopy, which in principle can simultaneously analyze all elements on the periodic table. Materials can be analyzed in terms of chemical composition in a two-dimensional, time efficient and minor destructive manner. These advantages predestine LIBS as a monitoring technique in the field of civil engineering. The decreasing service life of concrete infrastructures is a continuously growing problematic. A variety of intruding, harmful substances can damage the reinforcement or the concrete itself. To insure a sufficient service life a regular monitoring of the structure is necessary. LIBS offers many applications to accomplish a successful examination of the conditions of concrete structures. A selection of those applications are the 2D-evaluation of chlorine-, sodium- and sulfur-concentration, the identification of carbonation depths and the representation of the heterogeneity of concrete. LIBS obtains this information by using a pulsed laser with a short pulse length (some mJ), which is focused on the surfaces of the analyzed specimen, for this only an optical access is needed. Because of the high power density (some GW/cm²) a minimal amount of material is vaporized and transformed into a plasma. This plasma emits light depending on the chemical composition of the vaporized material. By analyzing the emitted light, information for every measurement point is gained. The chemical composition of the scanned area is visualized in a 2D-map with spatial resolutions up to 0.1 mm x 0.1 mm. Those 2D-maps can be converted into classic depth profiles, as typically seen for the results of chloride concentration provided by chemical analysis like potentiometric titration. However, the 2D-visualization offers many advantages like illustrating chlorine carrying cracks, direct imaging of the carbonation depth and in general allowing the separation of the aggregates from the cement paste. By calibrating the LIBS-System, not only qualitative but quantitative results can be obtained. Those quantitative results can also be based on the cement paste, while excluding the aggregates. An additional advantage of LIBS is its mobility. By using the mobile system, located at BAM, onsite measurements are feasible. The mobile LIBS-system was already used to obtain chloride, sodium and sulfur concentrations onsite of parking decks, bridges and sewage treatment plants even under hard conditions like ongoing construction work or rough weather. All those prospects make LIBS a promising method to secure the integrity of infrastructures in a sustainable manner.

Keywords: concrete, damage assessment, harmful substances, LIBS

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1631 Distribution of Putative Dopaminergic Neurons and Identification of D2 Receptors in the Brain of Fish

Authors: Shweta Dhindhwal

Abstract:

Dopamine is an essential neurotransmitter in the central nervous system of all vertebrates and plays an important role in many processes such as motor function, learning and behavior, and sensory activity. One of the important functions of dopamine is release of pituitary hormones. It is synthesized from the amino acid tyrosine. Two types of dopamine receptors, D1-like and D2-like, have been reported in fish. The dopamine containing neurons are located in the olfactory bulbs, the ventral regions of the pre-optic area and tuberal hypothalamus. Distribution of the dopaminergic system has not been studied in the murrel, Channa punctatus. The present study deals with identification of D2 receptors in the brain of murrel. A phylogenetic tree has been constructed using partial sequence of D2 receptor. Distribution of putative dopaminergic neurons in the brain has been investigated. Also, formalin induced hypertrophy of neurosecretory cells in murrel has been studied.

Keywords: dopamine, fish, pre-optic area, murrel

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1630 Optimization of Rehabilitation in Scapolohumeral Periarthrosis Using Botulinum Toxin

Authors: M. A. Akulov, V. O. Zaharov, A. A. Tomskij

Abstract:

Introduction: Scapulohumeral periarthrosis, resulting as a reaction to mechanical injury of shoulder tendons and muscles, is associated with high incidence of temporal and permanent disability. There is a strong need for investigation of treatment of that patient group. Severe pain leads to limitation of movements range, which result in secondary alterations of joint capsule and ligamentous apparatus. Muscle tension and edema, swelling of fascial and fibrous structures result in nerve and vascular compression in intramuscular and osseo-muscular-fibrous spaces. Botulinum toxin injection leads to decrease of muscle tone, increase of movements range and associated pain alleviation. Study aim: Optimization of rehabilitation process in scapolohumeral periarthrosis using Xeomin. Patients and methods: 40 patients aged 37-56 years with scapulohumeral periarthrosis were evaluated. Patients were divided into two groups according to treatment regimen. The first (main) group included 21 patients, receiving intramuscular Xeomin 150-200 U in the area of brachio-scapular joint and trigger points (inducing motion range limitation and pain). Treatment procedures were combined with physical therapy and osteopathic procedures. The second (control) group included 19 patients, receiving conventional physical therapy and osteopathic procedures. The evaluation and efficacy comparison was carried out using McGill pain questionnaire, Clinical Global Impression scale (CGI), and patient-reported increase of brachio-scapular joint movement range and pain decrease at 1, 3 and 6 months of treatment. Results. The study demonstrated a significant improvement in the main group after one month of treatment, which persisted during months of treatment. At baseline, rank pain index on McGill pain questionnaire was 18,4±4,9 and 17,8±5,1 in the main and control group, respectively (p > 0,05). At 1 month of treatment we observed a significant decrease of pain syndrome (no pain or modest pain) and increase of movement range in angular degrees in the main group (р < 0,05). In the control group significant improvements were observed only on the 3 month of treatment (р < 0,05), but at 6 months of treatment the improvement in pain syndrome and motion range in brachio-scapular joint was significantly smaller, than in the main group. Rank pain index on McGill pain scale was 5,2±1,8 in the main group compared to 12,0±2,6 in the control group (р < 0,05). At 6 months of treatment patients in the first group reported a significant/highly significant improvement of general health on CGI, whereas in the second group most patients reported a minimal improvement. We observed a sustained and persistent improvement of motion range in brachio-scapular joint in the main group. Conclusion: Xeomin injections as a part of rehabilitation process in scapulohumeral periarthrosis lead to reduced time and increased quality of rehabilitation.

Keywords: botulinum toxin, rehabilitation, scapulohumeral periarthrosis

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1629 Acute Antihyperglycemic Activity of a Selected Medicinal Plant Extract Mixture in Streptozotocin Induced Diabetic Rats

Authors: D. S. N. K. Liyanagamage, V. Karunaratne, A. P. Attanayake, S. Jayasinghe

Abstract:

Diabetes mellitus is an ever increasing global health problem which causes disability and untimely death. Current treatments using synthetic drugs have caused numerous adverse effects as well as complications, leading research efforts in search of safe and effective alternative treatments for diabetes mellitus. Even though there are traditional Ayurvedic remedies which are effective, due to a lack of scientific exploration, they have not been proven to be beneficial for common use. Hence the aim of this study is to evaluate the traditional remedy made of mixture of plant components, namely leaves of Murraya koenigii L. Spreng (Rutaceae), cloves of Allium sativum L. (Amaryllidaceae), fruits of Garcinia queasita Pierre (Clusiaceae) and seeds of Piper nigrum L. (Piperaceae) used for the treatment of diabetes. We report herein the preliminary results for the in vivo study of the anti-hyperglycaemic activity of the extracts of the above plant mixture in Wistar rats. A mixture made out of equal weights (100 g) of the above mentioned medicinal plant parts were extracted into cold water, hot water (3 h reflux) and water: acetone mixture (1:1) separately. Male wistar rats were divided into six groups that received different treatments. Diabetes mellitus was induced by intraperitoneal administration of streptozotocin at a dose of 70 mg/ kg in male Wistar rats in group two, three, four, five and six. Group one (N=6) served as the healthy untreated and group two (N=6) served as diabetic untreated control and both groups received distilled water. Cold water, hot water, and water: acetone plant extracts were orally administered in diabetic rats in groups three, four and five, respectively at different doses of 0.5 g/kg (n=6), 1.0 g/kg(n=6) and 1.5 g/kg(n=6) for each group. Glibenclamide (0.5 mg/kg) was administered to diabetic rats in group six (N=6) served as the positive control. The acute anti-hyperglycemic effect was evaluated over a four hour period using the total area under the curve (TAUC) method. The results of the test group of rats were compared with the diabetic untreated control. The TAUC of healthy and diabetic rats were 23.16 ±2.5 mmol/L.h and 58.31±3.0 mmol/L.h, respectively. A significant dose dependent improvement in acute anti-hyperglycaemic activity was observed in water: acetone extract (25%), hot water extract ( 20 %), and cold water extract (15 %) compared to the diabetic untreated control rats in terms of glucose tolerance (P < 0.05). Therefore, the results suggest that the plant mixture has a potent antihyperglycemic effect and thus validating their used in Ayurvedic medicine for the management of diabetes mellitus. Future studies will be focused on the determination of the long term in vivo anti-diabetic mechanisms and isolation of bioactive compounds responsible for the anti-diabetic activity.

Keywords: acute antihyperglycemic activity, herbal mixture, oral glucose tolerance test, Sri Lankan medicinal plant extracts

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1628 Effect of Temperature on the Permeability and Time-Dependent Change in Thermal Volume of Bentonite Clay During the Heating-Cooling Cycle

Authors: Nilufar Chowdhury, Fereydoun Najafian Jazi, Omid Ghasemi-Fare

Abstract:

The thermal effect on soil properties induces significant variations in hydraulic conductivity, which is attributable to temperature-dependent transitions in soil properties. With the elevation of temperature, there can be a notable increase in intrinsic permeability due to the degeneration of bound water molecules into a free state facilitated by thermal energy input. Conversely, thermal consolidation may cause a reduction in intrinsic permeability as soil particles undergo densification. This thermal response of soil permeability exhibits pronounced heterogeneity across different soil types. Furthermore, this temperature-induced disruption of the bound water within clay matrices can enhance the mineral-to-mineral contact, initiating irreversible deformation within the clay structure. This indicates that when soil undergoes heating-cooling cycles, plastic strain can develop, which needs to be investigated for every soil type to understand the thermo-hydro mechanical behavior of clay properly. This research aims to study the effect of the heating-cooling cycle on the intrinsic permeability and time-dependent evaluation of thermal volume change of sodium Bentonite clay. A temperature-controlled triaxial permeameter cell is used in this study. The selected temperature is 20° C, 40° C, 40° C and 80° C. The hydraulic conductivity of Bentonite clay under 100 kPa confining stresses was measured. Hydraulic conductivity analysis was performed on a saturated sample for a void ratio e = 0.9, corresponding to a dry density of 1.2 Mg/m3. Different hydraulic gradients were applied between the top and bottom of the sample to obtain a measurable flow through the sample. The hydraulic gradient used for the experiment was 4000. The diameter and thickness of the sample are 101. 6 mm, and 25.4 mm, respectively. Both for heating and cooling, the hydraulic conductivity at each temperature is measured after the flow reaches the steady state condition to make sure the volume change due to thermal loading is stabilized. Thus, soil specimens were kept at a constant temperature during both the heating and cooling phases for at least 10-18 days to facilitate the equilibration of hydraulic transients. To assess the influence of temperature-induced volume changes of Bentonite clay, the evaluation of void ratio change during this time period has been monitored. It is observed that the intrinsic permeability increases by 30-40% during the heating cycle. The permeability during the cooling cycle is 10-12% lower compared to the permeability observed during the heating cycle at a particular temperature. This reduction in permeability implies a change in soil fabric due to the thermal effect. An initial increase followed by a rapid decrease in void ratio was observed, representing the occurrence of possible osmotic swelling phenomena followed by thermal consolidation. It has been observed that after a complete heating-cooling cycle, there is a significant change in the void ratio compared to the initial void ratio of the sample. The results obtained suggest that Bentonite clay’s microstructure can change subject to a complete heating-cooling process, which regulates macro behavior such as the permeability of Bentonite clay.

Keywords: bentonite, permeability, temperature, thermal volume change

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1627 The Effects of the Russian Crisis on Turkish Tourism Sector: A Case of Antalya Province, Turkey

Authors: Huseyin Cetin, Halil Akmese, Sercan Aras, Vahit Aytekin

Abstract:

Economic crisis, terrorism, global crisis and the relations between countries are the factors affecting tourism industry and tourism industry is vulnerable against these factors. In our study, there are two dimensions about Russian crisis. The crisis between Russia and Ukraine and decreased oil prices in global market have been entailed Russian economic crisis. This crisis has induced that the ruble, Russian currency, has depreciated against American dollars and consequently the purchasing power of Russian has weakened. This is the first dimension of our study. Second dimension is a political crisis between Turkey and Russia owing to the fact that the Russian Warcraft was brought down by Turkish army. The aim of this study is to explain the impact of the consequences of Russian crisis on Turkish tourism industry. The study has been limited only Antalya province.

Keywords: economic crisis, Turkey-Russian crisis, Turkey's tourism industry, tourism in Turkey

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1626 Degradation of Irradiated UO2 Fuel Thermal Conductivity Calculated by FRAPCON Model Due to Porosity Evolution at High Burn-Up

Authors: B. Roostaii, H. Kazeminejad, S. Khakshournia

Abstract:

The evolution of volume porosity previously obtained by using the existing low temperature high burn-up gaseous swelling model with progressive recrystallization for UO2 fuel is utilized to study the degradation of irradiated UO2 thermal conductivity calculated by the FRAPCON model of thermal conductivity. A porosity correction factor is developed based on the assumption that the fuel morphology is a three-phase type, consisting of the as-fabricated pores and pores due to intergranular bubbles whitin UO2 matrix and solid fission products. The predicted thermal conductivity demonstrates an additional degradation of 27% due to porosity formation at burn-up levels around 120 MWd/kgU which would cause an increase in the fuel temperature accordingly. Results of the calculations are compared with available data.

Keywords: irradiation-induced recrystallization, matrix swelling, porosity evolution, UO₂ thermal conductivity

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1625 Improoving Readability for Tweet Contextualization Using Bipartite Graphs

Authors: Amira Dhokar, Lobna Hlaoua, Lotfi Ben Romdhane

Abstract:

Tweet contextualization (TC) is a new issue that aims to answer questions of the form 'What is this tweet about?' The idea of this task was imagined as an extension of a previous area called multi-document summarization (MDS), which consists in generating a summary from many sources. In both TC and MDS, the summary should ideally contain the most relevant information of the topic that is being discussed in the source texts (for MDS) and related to the query (for TC). Furthermore of being informative, a summary should be coherent, i.e. well written to be readable and grammatically compact. Hence, coherence is an essential characteristic in order to produce comprehensible texts. In this paper, we propose a new approach to improve readability and coherence for tweet contextualization based on bipartite graphs. The main idea of our proposed method is to reorder sentences in a given paragraph by combining most expressive words detection and HITS (Hyperlink-Induced Topic Search) algorithm to make up a coherent context.

Keywords: bipartite graphs, readability, summarization, tweet contextualization

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1624 Metal-Based Anticancer Agents: In vitro DNA Binding, Cleavage and Cytotoxicity

Authors: Mala Nath, Nagamani Kompelli, Partha Roy, Snehasish Das

Abstract:

Two new metal-based anticancer chemotherapeutic agents, [(Ph2Sn)2(HGuO)2(phen)Cl2] 1 and [(Ph3Sn)(HGuO)(phen)]- Cl.CH3OH.H2O 2, were designed, prepared and characterized by analytical and spectral (IR, ESI-Mass, 1H, 13C and 119Sn NMR) techniques. The proposed geometry of Sn(IV) in 1 and 2 is distorted octahedral and distorted trigonal-bipyramidal, respectively. Both 1 and 2 exhibit potential cytotoxicity in vitro against MCF-7, HepG-2 and DU-145 cell lines. The intrinsic binding constant (Kb) values of 1 (2.33 × 105 M-1) and 2 (2.46 × 105 M-1) evaluated from UV-Visible absorption studies suggest non-classical electrostatic mode of interaction via phosphate backbone of DNA double helix. The Stern-Volmer quenching constant (Ksv) of 1 (9.74 × 105 M-1) and 2 (2.9 × 106 M-1) determined by fluorescence studies suggests the groove binding and intercalation mode for 1 and 2, respectively. Effective cleavage of pBR322 DNA is induced by 1. Their interaction with DNA of cancer cells may account for potency.

Keywords: anticancer agents, DNA binding studies, NMR spectroscopy, organotin

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1623 Study on Electromagnetic Plasma Acceleration Using Rotating Magnetic Field Scheme

Authors: Takeru Furuawa, Kohei Takizawa, Daisuke Kuwahara, Shunjiro Shinohara

Abstract:

In the field of a space propulsion, an electric propulsion system has been developed because its fuel efficiency is much higher than a conventional chemical one. However, the practical electric propulsion systems, e.g., an ion engine, have a problem of short lifetime due to a damage of generation and acceleration electrodes of the plasma. A helicon plasma thruster is proposed as a long-lifetime electric thruster which has non-direct contact electrodes. In this system, both generation and acceleration methods of a dense plasma are executed by antennas from the outside of a discharge tube. Development of the helicon plasma thruster has been conducting under the Helicon Electrodeless Advanced Thruster (HEAT) project. Our helicon plasma thruster has two important processes. First, we generate a dense source plasma using a helicon wave with an excitation frequency between an ion and an electron cyclotron frequencies, fci and fce, respectively, applied from the outside of a discharge using a radio frequency (RF) antenna. The helicon plasma source can provide a high-density (~1019 m-3), a high-ionization ratio (up to several tens of percent), and a high particle generation efficiency. Second, in order to achieve high thrust and specific impulse, we accelerate the dense plasma by the axial Lorentz force fz using the product of the induced azimuthal current jθ and the static radial magnetic field Br, shown as fz = jθ × Br. The HEAT project has proposed several kinds of electrodeless acceleration schemes, and in our particular case, a Rotating Magnetic Field (RMF) method has been extensively studied. The RMF scheme was originally developed as a concept to maintain the Field Reversed Configuration (FRC) in a magnetically confined fusion research. Here, RMF coils are expected to generate jθ due to a nonlinear effect shown below. First, the rotating magnetic field Bω is generated by two pairs of RMF coils with AC currents, which have a phase difference of 90 degrees between the pairs. Due to the Faraday’s law, an axial electric field is induced. Second, an axial current is generated by the effects of an electron-ion and an electron-neutral collisions through the Ohm’s law. Third, the azimuthal electric field is generated by the nonlinear term, and the retarding torque generated by the collision effects again. Then, azimuthal current jθ is generated as jθ = - nₑ er ∙ 2π fRMF. Finally, the axial Lorentz force fz for plasma acceleration is generated. Here, jθ is proportional to nₑ and frequency of RMF coil current fRMF, when Bω is fully penetrated into the plasma. Our previous study has achieved 19 % increase of ion velocity using the 5 MHz and 50 A of the RMF coil power supply. In this presentation, we will show the improvement of the ion velocity using the lower frequency and higher current supplied by RMF power supply. In conclusion, helicon high-density plasma production and electromagnetic acceleration by the RMF scheme with a concept of electrodeless condition have been successfully executed.

Keywords: electric propulsion, electrodeless thruster, helicon plasma, rotating magnetic field

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1622 Elucidation of Dynamics of Murine Double Minute 2 Shed Light on the Anti-cancer Drug Development

Authors: Nigar Kantarci Carsibasi

Abstract:

Coarse-grained elastic network models, namely Gaussian network model (GNM) and Anisotropic network model (ANM), are utilized in order to investigate the fluctuation dynamics of Murine Double Minute 2 (MDM2), which is the native inhibitor of p53. Conformational dynamics of MDM2 are elucidated in unbound, p53 bound, and non-peptide small molecule inhibitor bound forms. With this, it is aimed to gain insights about the alterations brought to global dynamics of MDM2 by native peptide inhibitor p53, and two small molecule inhibitors (HDM201 and NVP-CGM097) that are undergoing clinical stages in cancer studies. MDM2 undergoes significant conformational changes upon inhibitor binding, carrying pieces of evidence of induced-fit mechanism. Small molecule inhibitors examined in this work exhibit similar fluctuation dynamics and characteristic mode shapes with p53 when complexed with MDM2, which would shed light on the design of novel small molecule inhibitors for cancer therapy. The results showed that residues Phe 19, Trp 23, Leu 26 reside in the minima of slowest modes of p53, pointing to the accepted three-finger binding model. Pro 27 displays the most significant hinge present in p53 and comes out to be another functionally important residue. Three distinct regions are identified in MDM2, for which significant conformational changes are observed upon binding. Regions I (residues 50-77) and III (residues 90-105) correspond to the binding interface of MDM2, including (α2, L2, and α4), which are stabilized during complex formation. Region II (residues 77-90) exhibits a large amplitude motion, being highly flexible, both in the absence and presence of p53 or other inhibitors. MDM2 exhibits a scattered profile in the fastest modes of motion, while binding of p53 and inhibitors puts restraints on MDM2 domains, clearly distinguishing the kinetically hot regions. Mode shape analysis revealed that the α4 domain controls the size of the cleft by keeping the cleft narrow in unbound MDM2; and open in the bound states for proper penetration and binding of p53 and inhibitors, which points to the induced-fit mechanism of p53 binding. P53 interacts with α2 and α4 in a synchronized manner. Collective modes are shifted upon inhibitor binding, i.e., second mode characteristic motion in MDM2-p53 complex is observed in the first mode of apo MDM2; however, apo and bound MDM2 exhibits similar features in the softest modes pointing to pre-existing modes facilitating the ligand binding. Although much higher amplitude motions are attained in the presence of non-peptide small molecule inhibitor molecules as compared to p53, they demonstrate close similarity. Hence, NVP-CGM097 and HDM201 succeed in mimicking the p53 behavior well. Elucidating how drug candidates alter the MDM2 global and conformational dynamics would shed light on the rational design of novel anticancer drugs.

Keywords: cancer, drug design, elastic network model, MDM2

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1621 Serious Gaming for Behaviour Change: A Review

Authors: Ramy Hammady, Sylvester Arnab

Abstract:

Significant attention has been directed to adopt game interventions practically to change certain behaviours in many disciplines such as health, education, psychology through many years. That’s due to the intrinsic motivation that games can cause and the substantial impact the games can leave on the player. Many review papers were induced to highlight and measure the effectiveness of the game’s interventions on changing behaviours; however, most of these studies neglected the game design process itself and the game features and elements that can stimuli changing behaviours. Therefore, this paper aims to identify the most game design mechanics and features that are the most influencing on changing behaviour during or after games interventions. This paper also sheds light on the theories of changing behaviours that clearly can led the game design process. This study gives directions to game designers to spot the most influential game features and mechanics for changing behaviour games in order to exploit it on the same manner.

Keywords: behaviour change, game design, serious gaming, gamification, review

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1620 Alterations of Malondialdehyde and Heat Shock Protein-27 in Sheep with Naturally Infected Liver Cystic Echinococcosis

Authors: K. Azimzadeh, S. Rasouli

Abstract:

The present study investigates whether malondialdehyde (MDA) and heat shock protein-27 (HSP-27) are altered in sheep with cystic echinococcosis (CE). For this purpose, forty parasitized and thirty healthy sheep were selected based on severe cystic form observation in liver and lack of blood parasite along with no cystic conformation in carcass respectively. The results revealed a significant decrease (p<0.01) in albumin (Alb) and total plasma protein (TPP) and a significant increase (p<0.01) in HSP-27, MDA, total bilirubin and unconjugated bilirubin in the infected group compared with healthy ones.The results indicate low levels of TPP and Alb reveal liver damage in suffered sheep and MDA elevation demonstrates oxidative stress in infected group. In addition, HSP-27 enhancement may attribute to disease-induced stress conditions.

Keywords: malondialdehyde, heat shock protein-27, Echinococcosis, blood parasites

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1619 Hepatoprotective Effect of Mycophenolate Mofetil against Tacrolimus Exposure in Rat

Authors: Ferjani Hanen, El Arem Amira, Boussema Ayed Imen, Bacha Hassen

Abstract:

Tacrolimus (TAC), a calcineurin inhibitor, is clinically used as an immunosuppressive agent in the transplant recipient, but its use associated-hepatotoxicity. Mycophenolate mofetil (MMF), an anti-metabolite, is a potent immunosuppressive drug. MMF is not hepatotoxic and is the most common adjunctive immunosuppressant for TAC. The effects of TAC and MMF combination in the liver is still not well understood. This work aimed to investigate their combined effect against in liver in rats Wistar after 24 h. The oral median lethal doses (LD50) of TAC and MMF alone were evaluated in rats are 240 mg/kg and 500 mg/kg respectively. Oral administration of the MMF at 50 mg/kg to male Wistar intoxicated with TAC at 60 mg/kg, demonstrated a significant protective effect by lowering the levels of hepatic markers enzymes (AST, ALT) in the serum rat. MMF attenuated oxidative stress by restoring the activities of SOD, CAT and by reducing the malondialdehyde (MDA) and protein carbonyl levels liver. This study provided evidence that MMF protects rat liver from TAC-induced injury and suggests a most combination use for organ transplantation.

Keywords: tacrolimus, mycophenolate mofetil, combination, liver, rat

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1618 Evaluating the Feasibility of Magnetic Induction to Cross an Air-Water Boundary

Authors: Mark Watson, J.-F. Bousquet, Adam Forget

Abstract:

A magnetic induction based underwater communication link is evaluated using an analytical model and a custom Finite-Difference Time-Domain (FDTD) simulation tool. The analytical model is based on the Sommerfeld integral, and a full-wave simulation tool evaluates Maxwell’s equations using the FDTD method in cylindrical coordinates. The analytical model and FDTD simulation tool are then compared and used to predict the system performance for various transmitter depths and optimum frequencies of operation. To this end, the system bandwidth, signal to noise ratio, and the magnitude of the induced voltage are used to estimate the expected channel capacity. The models show that in seawater, a relatively low-power and small coils may be capable of obtaining a throughput of 40 to 300 kbps, for the case where a transmitter is at depths of 1 to 3 m and a receiver is at a height of 1 m.

Keywords: magnetic induction, FDTD, underwater communication, Sommerfeld

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1617 Effect of Ultrasonic Vibration on the Dilution, Mechanical, and Metallurgical Properties in Cladding of 308 on Mild Steel

Authors: Sandeep Singh Sandhu, Karanvir Singh Ghuman, Parminder Singh Saini

Abstract:

The aim of the present investigation was to study the effect of ultrasonic vibration on the cladding of the AISI 308 on the mild steel plates using the shielded metal arc welding (SMAW). Ultrasonic vibrations were applied to molten austenitic stainless steel during the welding process. Due to acoustically induced cavitations and streaming there is a complete mixture of the clad metal and the base metal. It was revealed that cladding of AISI 308 over mild steel along with ultrasonic vibrations result in uniform and finer grain structures. The effect of the vibration on the dilution, mechanical properties and metallographic studies were also studied. It was found that the welding done using the ultrasonic vibration has the less dilution and CVN value for the vibrated sample was also high.

Keywords: surfacing, ultrasonic vibrations, mechanical properties, shielded metal arc welding

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1616 Effect of T6 and Re-Aging Heat Treatment on Mechanical Properties of 7055 Aluminum Alloy

Authors: M. Esmailian, M. Shakouri, A. Mottahedi, S. G. Shabestari

Abstract:

Heat treatable aluminium alloys such as 7075 and 7055, because of high strength and low density, are used widely in aircraft industry. For best mechanical properties, T6 heat treatment has recommended for this regards, but this temper treatment is sensitive to corrosion induced and Stress Corrosion Cracking (SCC) damage. For improving this property, the over-aging treatment (T7) applies to this alloy, but it decreases the mechanical properties up to 30 percent. Hence, to increase the mechanical properties, without any remarkable decrease in SCC resistant, Retrogression and Re-Aging (RRA) heat treatment is used. This treatment performs in a relatively short time. In this paper, the RRA heat treatment was applied to 7055 aluminum alloy and then effect of RRA time on the mechanical properties of 7055 has been investigated. The results show that the 40 minute time is suitable time for retrogression of 7055 aluminum alloy and ultimate strength increases up to 625MPa.

Keywords: 7055 Aluminum alloy, mechanical properties, SCC resistance, heat Treatment

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1615 MicroRNA 200c-3p Regulates Autophagy Mediated Upregulation of Endoplasmic Reticulum Stress in PC-3 Cells

Authors: Eun Jung Sohn, Hwan Tae Park

Abstract:

Autophagy is a cellular response to stress or environment on cell survival. Here, we investigated the role of ectopic expression of miR 200c-3p in autophagy. Ectopic expression of miR 200c-3p increased the expression of IRE1alpha, ATF6 and CHOP by western blot and RT-qPCR. Furthermore, the level of microRNA 200c-3p was enhanced by treatment of TG or overexpression of GRP 78. Also, ectopic expression of miR200c-3p increased the LC3 II expression by western blot and RT-qPCR. Also, we found that western blot assay showed that miR200c-3p inhibitor was blocked the starvation–induced LC3II levels. Furthermore, starvation stress increased the level of miR200c-3p in different kinetics. Ectopic expression of miR200c-3p attenuated LC3II expression in IRE1 siRNA transfected PC3 cells. Here, we first demonstrate that miR200c-3p regulates autophagy via ER stress pathway.

Keywords: Autophagy, ER stress, LC3II, miR200c-3p

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1614 Modification of a Commercial Ultrafiltration Membrane by Electrospray Deposition for Performance Adjustment

Authors: Elizaveta Korzhova, Sebastien Deon, Patrick Fievet, Dmitry Lopatin, Oleg Baranov

Abstract:

Filtration with nanoporous ultrafiltration membranes is an attractive option to remove ionic pollutants from contaminated effluents. Unfortunately, commercial membranes are not necessarily suitable for specific applications, and their modification by polymer deposition is a fruitful way to adapt their performances accordingly. Many methods are usually used for surface modification, but a novel technique based on electrospray is proposed here. Various quantities of polymers were deposited on a commercial membrane, and the impact of the deposit is investigated on filtration performances and discussed in terms of charge and hydrophobicity. The electrospray deposition is a technique which has not been used for membrane modification up to now. It consists of spraying small drops of polymer solution under a high voltage between the needle containing the solution and the metallic support on which membrane is stuck. The advantage of this process lies in the small quantities of polymer that can be coated on the membrane surface compared with immersion technique. In this study, various quantities (from 2 to 40 μL/cm²) of solutions containing two charged polymers (13 mmol/L of monomer unit), namely polyethyleneimine (PEI) and polystyrene sulfonate (PSS), were sprayed on a negatively charged polyethersulfone membrane (PLEIADE, Orelis Environment). The efficacy of the polymer deposition was then investigated by estimating ion rejection, permeation flux, zeta-potential and contact angle before and after the polymer deposition. Firstly, contact angle (θ) measurements show that the surface hydrophilicity is notably improved by coating both PEI and PSS. Moreover, it was highlighted that the contact angle decreases monotonously with the amount of sprayed solution. Additionally, hydrophilicity enhancement was proved to be better with PSS (from 62 to 35°) than PEI (from 62 to 53°). Values of zeta-potential (ζ were estimated by measuring the streaming current generated by a pressure difference on both sides of a channel made by clamping two membranes. The ζ-values demonstrate that the deposits of PSS (negative at pH=5.5) allow an increase of the negative membrane charge, whereas the deposits of PEI (positive) lead to a positive surface charge. Zeta-potentials measurements also emphasize that the sprayed quantity has little impact on the membrane charge, except for very low quantities (2 μL/m²). The cross-flow filtration of salt solutions containing mono and divalent ions demonstrate that polymer deposition allows a strong enhancement of ion rejection. For instance, it is shown that rejection of a salt containing a divalent cation can be increased from 1 to 20 % and even to 35% by deposing 2 and 4 μL/cm² of PEI solution, respectively. This observation is coherent with the reversal of the membrane charge induced by PEI deposition. Similarly, the increase of negative charge induced by PSS deposition leads to an increase of NaCl rejection from 5 to 45 % due to electrostatic repulsion of the Cl- ion by the negative surface charge. Finally, a notable fall in the permeation flux due to the polymer layer coated at the surface was observed and the best polymer concentration in the sprayed solution remains to be determined to optimize performances.

Keywords: ultrafiltration, electrospray deposition, ion rejection, permeation flux, zeta-potential, hydrophobicity

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1613 The Impact of the Covid-19 Crisis on the Information Behavior in the B2B Buying Process

Authors: Stehr Melanie

Abstract:

The availability of apposite information is essential for the decision-making process of organizational buyers. Due to the constraints of the Covid-19 crisis, information channels that emphasize face-to-face contact (e.g. sales visits, trade shows) have been unavailable, and usage of digitally-driven information channels (e.g. videoconferencing, platforms) has skyrocketed. This paper explores the question in which areas the pandemic induced shift in the use of information channels could be sustainable and in which areas it is a temporary phenomenon. While information and buying behavior in B2C purchases has been regularly studied in the last decade, the last fundamental model of organizational buying behavior in B2B was introduced by Johnston and Lewin (1996) in times before the advent of the internet. Subsequently, research efforts in B2B marketing shifted from organizational buyers and their decision and information behavior to the business relationships between sellers and buyers. This study builds on the extensive literature on situational factors influencing organizational buying and information behavior and uses the economics of information theory as a theoretical framework. The research focuses on the German woodworking industry, which before the Covid-19 crisis was characterized by a rather low level of digitization of information channels. By focusing on an industry with traditional communication structures, a shift in information behavior induced by an exogenous shock is considered a ripe research setting. The study is exploratory in nature. The primary data source is 40 in-depth interviews based on the repertory-grid method. Thus, 120 typical buying situations in the woodworking industry and the information and channels relevant to them are identified. The results are combined into clusters, each of which shows similar information behavior in the procurement process. In the next step, the clusters are analyzed in terms of the post and pre-Covid-19 crisis’ behavior identifying stable and dynamic information behavior aspects. Initial results show that, for example, clusters representing search goods with low risk and complexity suggest a sustainable rise in the use of digitally-driven information channels. However, in clusters containing trust goods with high significance and novelty, an increased return to face-to-face information channels can be expected after the Covid-19 crisis. The results are interesting from both a scientific and a practical point of view. This study is one of the first to apply the economics of information theory to organizational buyers and their decision and information behavior in the digital information age. Especially the focus on the dynamic aspects of information behavior after an exogenous shock might contribute new impulses to theoretical debates related to the economics of information theory. For practitioners - especially suppliers’ marketing managers and intermediaries such as publishers or trade show organizers from the woodworking industry - the study shows wide-ranging starting points for a future-oriented segmentation of their marketing program by highlighting the dynamic and stable preferences of elaborated clusters in the choice of their information channels.

Keywords: B2B buying process, crisis, economics of information theory, information channel

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1612 Developing Three-Dimensional Digital Image Correlation Method to Detect the Crack Variation at the Joint of Weld Steel Plate

Authors: Ming-Hsiang Shih, Wen-Pei Sung, Shih-Heng Tung

Abstract:

The purposes of hydraulic gate are to maintain the functions of storing and draining water. It bears long-term hydraulic pressure and earthquake force and is very important for reservoir and waterpower plant. The high tensile strength of steel plate is used as constructional material of hydraulic gate. The cracks and rusts, induced by the defects of material, bad construction and seismic excitation and under water respectively, thus, the mechanics phenomena of gate with crack are probing into the cause of stress concentration, induced high crack increase rate, affect the safety and usage of hydroelectric power plant. Stress distribution analysis is a very important and essential surveying technique to analyze bi-material and singular point problems. The finite difference infinitely small element method has been demonstrated, suitable for analyzing the buckling phenomena of welding seam and steel plate with crack. Especially, this method can easily analyze the singularity of kink crack. Nevertheless, the construction form and deformation shape of some gates are three-dimensional system. Therefore, the three-dimensional Digital Image Correlation (DIC) has been developed and applied to analyze the strain variation of steel plate with crack at weld joint. The proposed Digital image correlation (DIC) technique is an only non-contact method for measuring the variation of test object. According to rapid development of digital camera, the cost of this digital image correlation technique has been reduced. Otherwise, this DIC method provides with the advantages of widely practical application of indoor test and field test without the restriction on the size of test object. Thus, the research purpose of this research is to develop and apply this technique to monitor mechanics crack variations of weld steel hydraulic gate and its conformation under action of loading. The imagines can be picked from real time monitoring process to analyze the strain change of each loading stage. The proposed 3-Dimensional digital image correlation method, developed in the study, is applied to analyze the post-buckling phenomenon and buckling tendency of welded steel plate with crack. Then, the stress intensity of 3-dimensional analysis of different materials and enhanced materials in steel plate has been analyzed in this paper. The test results show that this proposed three-dimensional DIC method can precisely detect the crack variation of welded steel plate under different loading stages. Especially, this proposed DIC method can detect and identify the crack position and the other flaws of the welded steel plate that the traditional test methods hardly detect these kind phenomena. Therefore, this proposed three-dimensional DIC method can apply to observe the mechanics phenomena of composite materials subjected to loading and operating.

Keywords: welded steel plate, crack variation, three-dimensional digital image correlation (DIC), crack stel plate

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1611 Diallyl Trisulfide Protects the Rat Liver from CCl4-Induced Injury and Fibrogenesis by Attenuating Oxidative Stress

Authors: Xiao-Jing Zhu, Liang Zhou, Shi-Zhong Zheng

Abstract:

Various studies have shown that diallyl trisulfide (DATS) can protect the liver injury, and DATS has a strong antioxidant property. The aim of this study is to evaluate the in vivo role of DATS in protecting the liver against injury and fibrogenesis and further explores the underlying mechanisms. Our results demonstrated that DATS protected the liver from CCl4-caused injury by suppressing the elevation of ALT and AST activities, and by improving the histological architecture of the liver. Treatment with DATS or colchicine improved the liver fibrosis by sirius red staining and immunofluorescence. In addition, immunohistochemistry, western blot, and RT-PCR analyses indicated that DATS inhibited HSC activation. Furthermore, DATS attenuated oxidative stress by increasing glutathione and reducing lipid peroxides and malondialdehyde. These findings suggest that the protective effect of DATS on CCl4-caused liver injury and liver fibrogenesis was, at least partially, attributed to its antioxidant activity.

Keywords: liver fibrogenesis, liver injury, oxidative stress, DATS

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1610 2D PbS Nanosheets Synthesis and Their Applications as Field Effect Transistors or Solar Cells

Authors: T. Bielewicz, S. Dogan, C. Klinke

Abstract:

Two-dimensional, solution-processable semiconductor materials are interesting for low-cost electronic applications [1]. We demonstrate the synthesis of lead sulfide nanosheets and how their size, shape and height can be tuned by varying concentrations of pre-cursors, ligands and by varying the reaction temperature. Especially, the charge carrier confinement in the nanosheets’ height adjustable from 2 to 20 nm has a decisive impact on their electronic properties. This is demonstrated by their use as conduction channel in a field effect transistor [2]. Recently we also showed that especially thin nanosheets show a high carrier multiplication (CM) efficiency [3] which could make them, through the confinement induced band gap and high photoconductivity, very attractive for application in photovoltaic devices. We are already able to manufacture photovoltaic devices out of single nanosheets which show promising results.

Keywords: physical sciences, chemistry, materials, chemistry, colloids, physics, condensed-matter physics, semiconductors, two-dimensional materials

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1609 Polarization Dependent Flexible GaN Film Nanogenerators and Electroluminescence Properties

Authors: Jeong Min Baik

Abstract:

We present that the electroluminescence (EL) properties and electrical output power of flexible N-face p-type GaN thin films can be tuned by strain-induced piezo-potential generated across the metal-semiconductor-metal structures. Under different staining conditions (convex and concave bending modes), the transport properties of the GaN films can be changed due to the spontaneous polarization of the films. The I-V characteristics with the bending modes show that the convex bending can increase the current across the films by the decrease in the barrier height at the metal-semiconductor contact, increasing the EL intensity of the P-N junction. At convex bending, it is also shown that the flexible p-type GaN films can generate an output voltage of up to 1.0 V, while at concave bending, 0.4 V. The change of the band bending with the crystal polarity of GaN films was investigated using high-resolution photoemission spectroscopy. This study has great significance on the practical applications of GaN in optoelectronic devices and nanogenerators under a working environment.

Keywords: GaN, flexible, laser lift-off, nanogenerator

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1608 Evaluation of Anti-inflammatory Activities of Extracts Obtained from Capparis Erythrocarpos In-Vivo

Authors: Benedict Ofori, Kwabena Sarpong, Stephen Antwi

Abstract:

Background: Medicinal plants are utilized all around the world and are becoming increasingly important economically. The WHO notes that ‘inappropriate use of traditional medicines or practices can have negative or dangerous effects and that future research is needed to ascertain the efficacy and safety of such practices and medicinal plants used by traditional medicine systems. The poor around the world have limited access to palliative care or pain relief. Pharmacologists have been focused on developing safe and effective anti-inflammatory drugs. Most of the issues related to their use have been linked to the fact that numerous traditional and herbal treatments are classified in different nations as meals or dietary supplements. As a result, there is no need for evidence of the quality, efficacy, or safety of these herbal formulations before they are marketed. The fact that access to drugs meant for pain relief is limited in low-income countries means advanced studies should be done on home drugs meant for inflammation to close the gap. Methods: The ethanolic extracts of the plant were screened for the presence of 10 phytochemicals. The Pierce BCA Protein Assay Kit was used for the determination of the protein concentration of the egg white. The rats were randomly selected and put in 6 groups. The egg white was sub-plantar injected into the right-hand paws of the rats to induce inflammation. The animals were treated with the three plant extracts obtained from the root bark, stem, and leaves of the plant. The control groups were treated with normal saline, while the standard groups were treated with standard drugs indomethacin and celecoxib. Plethysmometer was used to measure the change in paw volume of the animals over the course of the experiment. Results: The results of the phytochemical screening revealed the presence of reducing sugars and saponins. Alkaloids were present in only R.L.S (1:1:1), and phytosterols were found in R.L(1:1) and R.L.S (1:1:1). The estimated protein concentration was found to be 103.75 mg/ml. The control group had an observable increase in paw volume, which indicated that inflammation was induced during the 5 hours. The increase in paw volume for the control group peaked at the 1st hour and decreased gradually throughout the experiment, with minimal changes in the paw volumes. The 2nd and 3rd groups were treated with 20 mg/kg of indomethacin and celecoxib. The anti-inflammatory activities of indomethacin and celecoxib were calculated to be 21.4% and 4.28%, respectively. The remaining 3 groups were treated with 2 dose levels of 200mg/kg plant extracts. R.L.S, R.L, and S.R.L had anti-inflammatory activities of 22.3%, 8.2%, and 12.07%, respectively. Conclusions: Egg albumin-induced paw model in rats can be used to evaluate the anti-inflammatory activity of herbs that might have potential anti-inflammatory activity. Herbal medications have potential anti-inflammatory activities and can be used to manage various inflammatory conditions if their efficacy and side effects are well studied. The three extracts all possessed anti-inflammatory activity, with R.L.S having the highest anti-inflammatory activity.

Keywords: inflammation, capparis erythrocarpos, anti-inflammatory activity, herbal medicine, paw volume, egg albumin

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1607 Engineered Control of Bacterial Cell-to-Cell Signaling Using Cyclodextrin

Authors: Yuriko Takayama, Norihiro Kato

Abstract:

Quorum sensing (QS) is a cell-to-cell communication system in bacteria to regulate expression of target genes. In gram-negative bacteria, activation on QS is controlled by a concentration increase of N-acylhomoserine lactone (AHL), which can diffuse in and out of the cell. Effective control of QS is expected to avoid virulence factor production in infectious pathogens, biofilm formation, and antibiotic production because various cell functions in gram-negative bacteria are controlled by AHL-mediated QS. In this research, we applied cyclodextrins (CDs) as artificial hosts for the AHL signal to reduce the AHL concentration in the culture broth below its threshold for QS activation. The AHL-receptor complex induced under the high AHL concentration activates transcription of the QS-target gene. Accordingly, artificial reduction of the AHL concentration is one of the effective strategies to inhibit the QS. A hydrophobic cavity of the CD can interact with the acyl-chain of the AHL due to hydrophobic interaction in aqueous media. We studied N-hexanoylhomoserine lactone (C6HSL)-mediated QS in Serratia marcescens; accumulation of C6HSL is responsible for regulation of the expression of pig cluster. Inhibitory effects of added CDs on QS were demonstrated by determination of prodigiosin amount inside cells after reaching stationary phase, because production of prodigiosin depends on the C6HSL-mediated QS. By adding approximately 6 wt% hydroxypropyl-β-CD (HP-β-CD) in Luria-Bertani (LB) medium prior to inoculation of S. maecescens AS-1, the intracellularly accumulated prodigiosin was drastically reduced to 7-10%, which was determined after the extraction of prodigiosin in acidified ethanol. The AHL retention ability of HP-β-CD was also demonstrated by Chromobacterium violacuem CV026 bioassay. The CV026 strain is an AHL-synthase defective mutant that activates QS solely by adding AHLs from outside of cells. A purple pigment violacein is induced by activation of the AHL-mediated QS. We demonstrated that the violacein production was effectively suppressed when the C6HSL standard solution was spotted on a LB agar plate dispersing CV026 cells and HP-β-CD. Physico-chemical analysis was performed to study the affinity between the immobilized CD and added C6HSL using a quartz crystal microbalance (QCM) sensor. The COOH-terminated self-assembled monolayer was prepared on a gold electrode of 27-MHz AT-cut quartz crystal. Mono(6-deoxy-6-N, N-diethylamino)-β-CD was immobilized on the electrode using water-soluble carbodiimide. The C6HSL interaction with the β-CD cavity was studied by injecting the C6HSL solution to a cup-type sensor cell filled with buffer solution. A decrement of resonant frequency (ΔFs) clearly showed the effective C6HSL complexation with immobilized β-CD and its stability constant for MBP-SpnR-C6HSL complex was on the order of 102 M-1. The CD has high potential for engineered control of QS because it is safe for human use.

Keywords: acylhomoserine lactone, cyclodextrin, intracellular signaling, quorum sensing

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