Search results for: mechanochemical activation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 979

Search results for: mechanochemical activation

499 Mutagenicity Evaluation of Locally Produced Biphasic Calcium Phosphate Using Ames Test

Authors: Nur Fathin Alia Che Wahab, Thirumulu Ponnuraj Kannan, Zuliani Mahmood, Ismail Ab. Rahman, Hanafi Ismail

Abstract:

Locally produced Biphasic Calcium Phosphate (BCP) consists of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) which is a promising material for dentin and bone regeneration as well as in tissue engineering applications. The study was carried out to investigate the mutagenic effect of locally produced BCP using Ames test. Mutagenicity was evaluated with and without the addition of metabolic activation system (S9). This study was performed on Salmonella typhimurium TA98, TA102, TA1537, and TA1538 strains using preincubation assay method. The doses tested were 5000, 2500, 1250, 625, 313 µg/plate. Negative and positive controls were also included. The bacteria were incubated for 48 hours at 37 ± 0.5 °C. Then, the revertant colonies were counted. Data obtained were evaluated using non-statistical method. The mean number of revertant colonies in strains with and without S9 mix treated with locally produced BCP was less than double when compared to negative control for all the tested concentrations. The results from this study indicate that the locally produced BCP is non-mutagenic under the present test conditions.

Keywords: ames test, biphasic calcium phosphate, dentin regeneration, mutagenicity

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498 Rauvolfine B Isolated from the Bark of Rauvolfia reflexa (Apocynaceae) Induces Apoptosis through Activation of Caspase-9 Coupled with S Phase Cell Cycle Arrest

Authors: Mehran Fadaeinasab, Hamed Karimian, Najihah Mohd Hashim, Hapipah Mohd Ali

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In this study, three indole alkaloids namely; rauvolfine B, macusine B, and isoreserpiline have been isolated from the dichloromethane crude extract of Rauvolfia reflexa bark (Apocynaceae). The structural elucidation of the isolated compounds has been performed using spectral methods such as UV, IR, MS, 1D, and 2D NMR. Rauvolfine B showed anti proliferation activity on HCT-116 cancer cell line, its cytotoxicity induction was observed using MTT assay in eight different cell lines. Annexin-V is serving as a marker for apoptotic cells and the Annexin-V-FITC assay was carried out to observe the detection of cell-surface Phosphatidylserine (PS). Apoptosis was confirmed by using caspase-8 and -9 assays. Cell cycle arrest was also investigated using flowcytometric analysis. rauvolfine B had exhibited significantly higher cytotoxicity against HCT-116 cell line. The treatment significantly arrested HCT-116 cells in the S phase. Together, the results presented in this study demonstrated that rauvolfine B inhibited the proliferation of HCT-116 cells and programmed cell death followed by cell cycle arrest.

Keywords: apocynacea, indole alkaloid, apoptosis, cell cycle arrest

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497 Synthesis, Characterization and Electrical Studies of Solid Polymer Electrolyte (1-x) PANI-KAg₄I₅.xAl₂O₃

Authors: Rafiuddin

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Solid polymer electrolytes have emerged as an area of interest in the field of solid state chemistry owing to their facile and cost-effective synthesis and number of applications in different areas of chemistry, extending over a wide range of temperatures. In the present work, polymer composite solid electrolyte comprising of Polyaniline (PANI) as polymer and potassium silver iodide (KAg4I5) using alumina (Al2O3) of different compositions having the formula (1-x) PANI- KAg4I5. x Al2O3 with x ranging from 0.0 to 0.5 was prepared by solid state reaction method. The structural elucidation and characterization was done by X- Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric- Differential Thermal Analysis (TG-DTA) and Impedance Spectroscopy. The thermal analysis shows a phase transition at 147°C attributed to β-α phase transition of AgI due to the disproportionation of KAg4I5 to AgI and KAg2I3 at temperatures higher than 36°C. The X Ray diffraction analysis also confirms the presence of both AgI and KAg2I3 in the samples. The conductivities recorded over a temperature range of 40-250° C lie in the range of 10-1 to 10-3 S cm-1. Maximum conductivity was seen in the compositon x = 0.4 i.e. 1.84 × 10-2 Scm-1 at 313 K and 1.38 × 10-1 Scm-1 at 513 K, with a minimum activation energy of 0.14 eV.

Keywords: polymer solid electrolytes, XRD, DTA, electrical conductivity, impedance spectroscopy

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496 The Overexpression of Horsegram MURLK Improves Regulation of Cell Death and Defense Responses to Microbial Pathogens

Authors: Shikha Masand, Sudesh Kumar Yadav

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Certain protein kinases have been shown to be crucial for plant cell signaling pathways associated with plant immune responses. Here we identified a horsegram [Macrotyloma uniflorum (Lam.) Verdc.] malectin-like leucine rich receptor-like protein kinase (RLK) gene MuRLK. The functional MuRLK protein preferentially binds to mannose and N-acetyl glucosamine residues. MuRLK exists in the cytoplasm and also localizes to the plasma membrane of plant cells via its N-terminus. Over-expression of MuRLK in Arabidopsis enhances the basal resistance to infection with Pseudomonas syringae pv. tomato, Alternaria brassicicola and Hyaloperonospora arabidopsidis, are associated with elevated ROS bursts, MAPK activation, thus ultimately leading to hypersensitive cell death. Moreover, salicylic acid-dependent and jasmonic acid-dependent defense responses are also enhanced in the MuRLK-overexpressed plants that lead to HR-induced cell death. Together, these results suggest that MuRLK plays a key role in the regulation of plant cell death, early and late defense responses after the recognition of microbial pathogens.

Keywords: horsegram, Pseudomonas syringae pv. tomato, MuRLK, ROS burst, cell death, plant defense

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495 Health Promoting Properties of Phytochemicals from Rosemary (Rosmarinus officinalis) for Cancer and Inflammatory Bowel Disease

Authors: Jeremy J. Johnson

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Mediterranean herbs including rosemary (Rosmarinus officinalis) contain a variety of phytochemicals including diterpenes that possess extensive biological activity. Applications of diterpenes, including the more abundant forms carnosol and carnosic acid, have been shown to possess anti-cancer, anti-inflammatory, anti-oxidant, and anti-proliferation properties. To confirm these properties, we have evaluated rosemary extract and selected diterpenes for biological activity in cancer and inflammatory models. Our preliminary data have revealed that select diterpenes can disrupt androgen receptor functionality in prostate and breast cancer cells. This property is unique among natural products for hormone-responsive cancers. The second area of interest has been evaluating rosemary extract and selected diterpenes for activation of sestrin-2, an antioxidant protein, in colon cancer cells. A combination of in vitro and in vivo approaches have been utilized to characterize the activity of rosemary diterpenes in rosemary. Taken together, these results suggest that phytochemicals found in rosemary have distinct pharmacological actions for disrupting cell-signaling pathways in cancer and inflammatory bowel disease.

Keywords: rosemary, diterpene, cancer, inflammation

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494 Role of Sodium Concentration, Waiting Time and Constituents’ Temperature on the Rheological Behavior of Alkali Activated Slag Concrete

Authors: Muhammet M. Erdem, Erdoğan Özbay, Ibrahim H. Durmuş, Mustafa Erdemir, Murat Bikçe, Müzeyyen Balçıkanlı

Abstract:

In this paper, rheological behavior of alkali activated slag concretes were investigated depending on the sodium concentration (SC), waiting time (WT) after production, and constituents’ temperature (CT) parameters. For this purpose, an experimental program was conducted with four different SCs of 1.85, 3.0, 4.15, and 5.30%, three different WT of 0 (just after production), 15, and 30 minutes and three different CT of 18, 30, and 40 °C. Solid precursors are activated by water glass and sodium hydroxide solutions with silicate modulus (Ms = SiO2/Na2O) of 1. Slag content and (water + activator solution)/slag ratio were kept constant in all mixtures. Yield stress and plastic viscosity values were defined for each mixture by using the ICAR rheometer. Test results were demonstrated that all of the three studied parameters have tremendous effect on the yield stress and plastic viscosity values of the alkali activated slag concretes. Increasing the SC, WT, and CT drastically augmented the rheological parameters. At the 15 and 30 minutes WT after production, most of the alkali activated slag concretes were set instantaneously, and rheological measurements were not performed.

Keywords: alkali activation, slag, rheology, yield stress, plastic viscosity

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493 Feature Extractions of EMG Signals during a Constant Workload Pedaling Exercise

Authors: Bing-Wen Chen, Alvin W. Y. Su, Yu-Lin Wang

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Electromyography (EMG) is one of the important indicators during exercise, as it is closely related to the level of muscle activations. This work quantifies the muscle conditions of the lower limbs in a constant workload exercise. Surface EMG signals of the vastus laterals (VL), vastus medialis (VM), rectus femoris (RF), gastrocnemius medianus (GM), gastrocnemius lateral (GL) and Soleus (SOL) were recorded from fourteen healthy males. The EMG signals were segmented in two phases: activation segment (AS) and relaxation segment (RS). Period entropy (PE), peak count (PC), zero crossing (ZC), wave length (WL), mean power frequency (MPF), median frequency (MDF) and root mean square (RMS) are calculated to provide the quantitative information of the measured EMG segments. The outcomes reveal that the PE, PC, ZC and RMS have significantly changed (p<.001); WL presents moderately changed (p<.01); MPF and MDF show no changed (p>.05) during exercise. The results also suggest that the RS is also preferred for performance evaluation, while the results of the extracted features in AS are usually affected directly by the amplitudes. It is further found that the VL exhibits the most significant changes within six muscles during pedaling exercise. The proposed work could be applied to quantify the stamina analysis and to predict the instant muscle status in athletes.

Keywords: electromyographic feature extraction, muscle status, pedaling exercise, relaxation segment

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492 Recovery of Hydrogen Converter Efficiency Affected by Poisoning of Catalyst with Increasing of Temperature

Authors: Enayat Enayati, Reza Behtash

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The purpose of the H2 removal system is to reduce a content of hydrogen and other combustibles in the CO2 feed owing to avoid developing a possible explosive condition in the synthesis. In order to reduce the possibility of forming an explosive gas mixture in the synthesis as much as possible, the hydrogen percent in the fresh CO2, will be removed in hydrogen converter. Therefore the partly compressed CO2/Air mixture is led through Hydrogen converter (Reactor) where the H2, present in the CO2, is reduced by catalytic combustion to values less than 50 ppm (vol). According the following exothermic chemical reaction: 2H2 + O2 → 2H2O + Heat. The catalyst in hydrogen converter consist of platinum on a aluminum oxide carrier. Low catalyst activity maybe due to catalyst poisoning. This will result in an increase of the hydrogen content in the CO2 to the synthesis. It is advised to shut down the plant when the outlet of hydrogen converter increased above 100 ppm, to prevent undesirable gas composition in the plant. Replacement of catalyst will be time exhausting and costly so as to prevent this, we increase the inlet temperature of hydrogen converter according to following Arrhenius' equation: K=K0e (-E_a/RT) K is rate constant of a chemical reaction where K0 is the pre-exponential factor, E_a is the activation energy, and R is the universal gas constant. Increment of inlet temperature of hydrogen converter caused to increase the rate constant of chemical reaction and so declining the amount of hydrogen from 125 ppm to 70 ppm.

Keywords: catalyst, converter, poisoning, temperature

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491 Molecular Motors in Smart Drug Delivery Systems

Authors: Ainoa Guinart, Maria Korpidou, Daniel Doellerer, Cornelia Palivan, Ben L. Feringa

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Stimuli responsive systems arise from the need to meet unsolved needs of current molecular drugs. Our study presents the design of a delivery system with high spatiotemporal control and tuneable release profiles. We study the incorporation of a hydrophobic synthetic molecular motor into PDMS-b-PMOXA block copolymer vesicles to create a self-assembled system. We prove their successful incorporation and selective activation by low powered visible light (λ 430 nm, 6.9 mW). We trigger the release of a fluorescent dye with high release efficiencies over sequential cycles (up to 75%) with the ability to turn on and off the release behaviour on demand by light irradiation. Low concentrations of photo-responsive units are proven to trigger release down to 1 mol% of molecular motor. Finally, we test our system in relevant physiological conditions using a lung cancer cell line and the encapsulation of an approved drug. Similar levels of cell viability are observed compared to the free-given drugshowing the potential of our platform to deliver functional drugs on demand with the same efficiency and lower toxicity.

Keywords: molecular motor, polymer, drug delivery, light-responsive, cancer, selfassembly

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490 Influence of Electrode Assembly on Catalytic Activation and Deactivation of a PT Film Immobilized H+ Conducting Solid Electrolyte in Electrocatalytic Reduction Reactions

Authors: M. A. Hasnat, M. Amirul Islam, M. A. Rashed, Jamil. Safwan, M. Mahabubul Alam

Abstract:

Symmetric (Cu–Pt|Nafion|Pt–Cu) and asymmetric(Pt|Nafion|Pt–Cu) assemblies were fabricated to study the nitrate reduction processes at the cathode. The electrocatalytic nitrate reduction reactions were performed in these assemblies in order to investigate the prerequisite for the enhanced catalytic activity, electrochemical cell durability as well as preferable product selectivity resulting from the reduction of nitrate at the cathode. It has been observed for the symmetric assembly that Cu particles were oxidized on the anode surface under an applied potential and the resulting copper ions migrated to the cathode surface through the Nafion membrane, which deposited as copper oxide on the cathode surface. The formation of this copper oxide covering layer on the Pt–Cu cathode surface is attributed as the reason for the deactivation of the cathode that governed the reduced nitrate reduction along with increasing nitrite selectivity. These problems were addressed and resolved with the asymmetric design of the electrocatalytic reactor, where enhanced hydrogen evolution activates the surface by eroding the CuO over layer as well as speeding up the slow rate determining hydrogenation reactions.

Keywords: membrane, nitrate, electrocatalysis, voltammetry, electrolysis

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489 Vitamin D Deficiency is Associated with Increases IgE Receptors in Children with Asthma

Authors: A. Vijayendra Chary, R. Hemalatha

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Background: Vitamin D is a potent modulator of the immune system and is involved in regulating cell proliferation and differentiation. Vitamin D deficiency has been linked to increased severity of asthma in children. Asthma has dramatically increased in past decades, particular in developing countries and affects up to 20% of the population. IgE and its receptors, CD23 (FcεRII) and CD 21, play an essential role in all allergic conditions. Methods: A case control study was conducted on asthma and age and sex matched control children. 25 hydroxyvitamin D3 was quantified by HPLC; CD23; and CD21 expression on B cells were performed by flow cytometry. Total Histamine, total IGE and IL-5 and IFN-γ cytokines were determined by ELISA in blood samples of bronchial asthma (n=45) and control children (n=45). Results: The mean ± SE of vitamin D was significantly (p<0.05) low in asthma children (13.6±0.54 ng/mL) than in controls (17.4 ± 0.37 ng/mL). The mean (%) ± SE of CD23 and CD21 expression on B cells were significantly (p<0.01) high in asthma (1.02±0.09; 1.67± 0.13), when compared to controls (0.24±0.01; 0.94±0.03) respectively. The mean± SE of Serum IgE and blood histamine levels in asthma children (354.52 ± 17.33 IU/mL; 53.27 ± 2.54 nM/mL) were increased (P<0.05) when compared to controls (183.12±17.62 IU/mL 39.34±4.16 nM/mL) respectively and IFN-γ (Th1 cytokine) was lower (P<0.01) (16.37±1.27 pg/mL) than in controls (43.34±6.21 pg/mL). Conclusion: Our study provides evidence that low vitamin D levels are associated with increased IgE receptors CD23 and CD21 on B cells. In addition, there was preferential activation of Th2 (IL-5) and suppression of Th1 (IFN-γ) cytokines in children with asthma.

Keywords: bronchial asthma, CD23, IgE, vitamin D

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488 Cellulose Acetate Nanofiber Modification for Regulating Astrocyte Activity via Simple Heat Treatment

Authors: Sang-Myung Jung, Jeong Hyun Ju, Gwang Heum Yoon, Hwa Sung Shin

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Central nervous system (CNS) consists of neuronal cell and supporting cells. Astrocytes are the most common supporting cells and play roles in metabolism between neurons and blood vessel. For this function, engineered astrocytes have been studied as a therapeutic source for CNS injury. In neural tissue engineering, nanofiber has been suggested as an effective scaffold for providing structure and mechanical properties influencing physiology. Cellulose acetate (CA) has been investigated for material to fabricate scaffold because of its biocompatibility, biodegradability and fine thermal stability. In this research, CA nanofiber was modified via heat treatment and its effect on astrocyte activity was evaluated. Adhesion and viability of astrocyte were increased in proportion to stiffness. Additionally, expression of GFAP, a marker of astrocyte activation, was increased via stiffness of scaffold. This research suggests a simple modification method to change stiffness of CA nanofiber and shows cellular behavior affecting stiffness of three-dimensional scaffold independently. For the results, we highlight that the stiffness is a factor to regulate astrocyte activity.

Keywords: astrocyte, cellulose acetate, cell therapy, stiffness of scaffold

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487 Activation of Google Classroom Features to Engage Introvert Students in Comprehensible Output

Authors: Raghad Dwaik

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It is well known in language acquisition literature that a mere understanding of a reading text is not enough to help students build proficiency in comprehension. Students should rather follow understanding by attempting to express what has been understood by pushing their competence to the limit. Learners' attempt to push their competence was given the term "comprehensible output" by Swain (1985). Teachers in large classes, however, find it sometimes difficult to give all students a chance to communicate their views or to share their ideas during the short class time. In most cases, students who are outgoing dominate class discussion and get more opportunities for practice which leads to ignoring the shy students totally while helping the good ones become better. This paper presents the idea of using Google Classroom features of posting and commenting to allow students who hesitate to participate in class discussions about a reading text to write their views on the wall of a Google Classroom and share them later after they have received feedback and comments from classmates. Such attempts lead to developing their proficiency through additional practice in comprehensible output and to enhancing their confidence in themselves and their views. It was found that virtual classroom interaction would help students maintain vocabulary, use more complex structures and focus on meaning besides form.

Keywords: learning groups, reading TESOL, Google Classroom, comprehensible output

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486 The Role of Arousal in Time Perception: Implications for Emotional Driving

Authors: Ewa Siedlecka

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Emotional stress is an important risk factor in the rate and severity of traffic accidents. Moreover, incorrect time perception is implicated in the increase of traffic violations, such as running red lights or collisions. While the role of emotional arousal on perceived time is well-established, the role of physiological arousal in time perception remains unexamined. Specific emotions can be, however, associated with distinct physiological responses. In the current research, two studies examined the role of physiological arousal in time perception. In the first experiment, 41 participants engaged in a cold pressor task and had their time perception measured throughout the experiment. In the second study, 138 participants engaged in either isometric or deep breathing exercises. These activities were designed to simulate the sympathetic and parasympathetic nervous systems, respectively. Participants completed a bisection task to measure time perception in both studies, as well as a physiological response via an Electrocardiography (ECG). Results found that activation of the parasympathetic nervous system is associated with greater time perception. These findings are discussed with reference to models of time perception, as well as implications for emotional driving and misperceptions of speed. It is important to consider the role of physiology in the misperception of time, as these factors can lead to increases in driving accidents.

Keywords: emotions, nervous system, physiology, time perception

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485 Properties of Bio-Phenol Formaldehyde Composites Filled with Empty Fruit Bunch Fiber

Authors: Sharifah Nabihah Syed Jaafar, Umar Adli Amran, Rasidi Roslan, Chia Chin Hua, Sarani Zakaria

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Bio-composites derived from plant fiber and bio-derived polymer, are likely more ecofriendly and demonstrate competitive performance with petroleum based. In this research, the green phenolic resin was used as a matrix and oil palm empty fruit bunch fiber (EFB) was used as filler. The matrix was synthesized from soda lignin, phenol and hydrochloric acid as a catalyst. The phenolic resin was synthesized via liquefaction and condensation to enhance the combination of phenol during the process. Later, the phenolic resin was mixed with EFB by using mechanical stirrer and was molded with hot press at 180 oC. In this research, the composites were prepared with EFB content of 5%, 10%, 15% and 20%. The samples that viewed under scanning electron microscopy (SEM) showed that the EFB filler remained embedded in the resin. From impact and hardness testing, samples 10% of EFB showed the optimum properties meanwhile sample 15% showed the optimum properties for flexural testing. Thermal stability of the composites was investigated using thermogravimetric (TGA) analysis and found that the weight loss and the activation energy (Ea) of the composites samples were decreased as the filler content increased.

Keywords: EFB, liquefaction, phenol formaldehyde, lignin

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484 Neural Correlates of Diminished Humor Comprehension in Schizophrenia: A Functional Magnetic Resonance Imaging Study

Authors: Przemysław Adamczyk, Mirosław Wyczesany, Aleksandra Domagalik, Artur Daren, Kamil Cepuch, Piotr Błądziński, Tadeusz Marek, Andrzej Cechnicki

Abstract:

The present study aimed at evaluation of neural correlates of humor comprehension impairments observed in schizophrenia. To investigate the nature of this deficit in schizophrenia and to localize cortical areas involved in humor processing we used functional magnetic resonance imaging (fMRI). The study included chronic schizophrenia outpatients (SCH; n=20), and sex, age and education level matched healthy controls (n=20). The task consisted of 60 stories (setup) of which 20 had funny, 20 nonsensical and 20 neutral (not funny) punchlines. After the punchlines were presented, the participants were asked to indicate whether the story was comprehensible (yes/no) and how funny it was (1-9 Likert-type scale). fMRI was performed on a 3T scanner (Magnetom Skyra, Siemens) using 32-channel head coil. Three contrasts in accordance with the three stages of humor processing were analyzed in both groups: abstract vs neutral stories - incongruity detection; funny vs abstract - incongruity resolution; funny vs neutral - elaboration. Additionally, parametric modulation analysis was performed using both subjective ratings separately in order to further differentiate the areas involved in incongruity resolution processing. Statistical analysis for behavioral data used U Mann-Whitney test and Bonferroni’s correction, fMRI data analysis utilized whole-brain voxel-wise t-tests with 10-voxel extent threshold and with Family Wise Error (FWE) correction at alpha = 0.05, or uncorrected at alpha = 0.001. Between group comparisons revealed that the SCH subjects had attenuated activation in: the right superior temporal gyrus in case of irresolvable incongruity processing of nonsensical puns (nonsensical > neutral); the left medial frontal gyrus in case of incongruity resolution processing of funny puns (funny > nonsensical) and the interhemispheric ACC in case of elaboration of funny puns (funny > neutral). Additionally, the SCH group revealed weaker activation during funniness ratings in the left ventro-medial prefrontal cortex, the medial frontal gyrus, the angular and the supramarginal gyrus, and the right temporal pole. In comprehension ratings the SCH group showed suppressed activity in the left superior and medial frontal gyri. Interestingly, these differences were accompanied by protraction of time in both types of rating responses in the SCH group, a lower level of comprehension for funny punchlines and a higher funniness for absurd punchlines. Presented results indicate that, in comparison to healthy controls, schizophrenia is characterized by difficulties in humor processing revealed by longer reaction times, impairments of understanding jokes and finding nonsensical punchlines more funny. This is accompanied by attenuated brain activations, especially in the left fronto-parietal and the right temporal cortices. Disturbances of the humor processing seem to be impaired at the all three stages of the humor comprehension process, from incongruity detection, through its resolution to elaboration. The neural correlates revealed diminished neural activity of the schizophrenia brain, as compared with the control group. The study was supported by the National Science Centre, Poland (grant no 2014/13/B/HS6/03091).

Keywords: communication skills, functional magnetic resonance imaging, humor, schizophrenia

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483 Precocious Puberty Due to an Autonomous Ovarian Cyst in a 3-Year-Old Girl: Case Report

Authors: Aleksandra Chałupnik, Zuzanna Chilimoniuk, Joanna Borowik, Aleksandra Borkowska, Anna Torres

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Background: Precocious puberty is the occurrence of secondary sexual characteristics in girls before the age of 8. The diverse etiology of premature puberty is crucial to determine whether it is true precocious puberty, depending on the activation of the hypothalamic-pituitary-gonadal axis, or pseudo-precocious, which is independent of the activation of this axis. Whatever the cause, premature action of the sex hormones leads to the common symptoms of various forms of puberty. These include the development of sexual characteristics, acne, acceleration of growth rate and acceleration of skeletal maturation. Due to the possible genetic basis of the disorders, an interdisciplinary search for the cause is needed. Case report: The case report concerns a patient of a pediatric gynecology clinic who, at the age of two years, developed advanced thelarhe (M3) and started recurrent vaginal bleeding. In August 2019, gonadotropin suppression initially and after LHRH stimulation and high estradiol levels were reported at the Endocrinology Department. Imaging examinations showed a cyst in the right ovary projection. The bone age was six years. The entire clinical picture indicated pseudo- (peripheral) precocious in the course of ovarian autonomic cyst. In the follow-up ultrasound performed in September, the image of the cyst was stationary and normalization of estradiol levels and clinical symptoms was noted. In December 2019, cyst regression and normal gonadotropin and estradiol concentrations were found. In June 2020, white mucus tinged with blood on the underwear, without any other disturbing symptoms, was observed for several days. Two consecutive USG examinations carried out in the same month confirmed the change in the right ovary, the diameter of which was 25 mm with a very high level of estradiol. Germinal tumor markers were normal. On the Tanner scale, the patient scored M2P1. The labia and hymen had puberty features. The correct vaginal entrance was visible. Another active vaginal bleeding occurred in the first week of July 2020. The considered laparoscopic treatment was abandoned due to the lack of oncological indications. Treatment with Tamoxifen was recommended in July 2020. In the initiating period of treatment, no maturation progression, and even reduction of symptoms, no acceleration of growth and a marked reduction in the size of the cysts were noted. There was no bleeding. After the size of the cyst and hormonal activity increased again, the treatment was changed to Anastrozole, the effect of which led to a reduction in the size of the cyst. Conclusions: The entire clinical picture indicates alleged (peripheral) puberty. Premature puberty in girls, which is manifested as enlarged mammary glands with high levels of estrogens secreted by autonomic ovarian cysts and prepubertal levels of gonadotropins, may indicate McCune-Albright syndrome. Vaginal bleeding may also occur in this syndrome. Cancellation of surgical treatment of the cyst made it impossible to perform a molecular test that would allow to confirm the diagnosis. Taking into account the fact that cysts are often one of the first symptoms of McCune-Albrigt syndrome, it is important to remember about multidisciplinary care for the patient and careful search for skin and bone changes or other hormonal disorders.

Keywords: McCune Albrigth's syndrome, ovarian cyst, pediatric gynaecology, precocious puberty

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482 Fast-Modulated Surface-Confined Plasma for Catalytic Nitrogen Fixation and Energy Intensification

Authors: Pradeep Lamichhane, Nima Pourali, E. V. Rebrov, Volker Hessel

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Nitrogen fixation is critical for plants for the biosynthesis of protein and nucleic acid. Most of our atmosphere is nitrogen, yet plants cannot directly absorb it from the air, and natural nitrogen fixation is insufficient to meet the demands. This experiment used a fast-modulated surface-confined atmospheric pressure plasma created by a 6 kV (peak-peak) sinusoidal power source with a repetition frequency of 68 kHz to fix nitrogen. Plasmas have been proposed for excitation of nitrogen gas, which quickly oxidised to NOX. With different N2/O2 input ratios, the rate of NOX generation was investigated. The rate of NOX production was shown to be optimal for mixtures of 60–70% O2 with N2. To boost NOX production in plasma, metal oxide catalysts based on TiO2 were coated over the dielectric layer of a reactor. These results demonstrate that nitrogen activation was more advantageous in surface-confined plasma sources because micro-discharges formed on the sharp edges of the electrodes, which is a primary function attributed to NOX synthesis and is further enhanced by metal oxide catalysts. The energy-efficient and sustainable NOX synthesis described in this study will offer a fresh perspective for ongoing research on green nitrogen fixation techniques.

Keywords: nitrogen fixation, fast-modulated, surface-confined, sustainable

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481 Identifying Metabolic Pathways Associated with Neuroprotection Mediated by Tibolone in Human Astrocytes under an Induced Inflammatory Model

Authors: Daniel Osorio, Janneth Gonzalez, Andres Pinzon

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In this work, proteins and metabolic pathways associated with the neuroprotective response mediated by the synthetic neurosteroid tibolone under a palmitate-induced inflammatory model were identified by flux balance analysis (FBA). Three different metabolic scenarios (‘healthy’, ‘inflamed’ and ‘medicated’) were modeled over a gene expression data-driven constructed tissue-specific metabolic reconstruction of mature astrocytes. Astrocyte reconstruction was built, validated and constrained using three open source software packages (‘minval’, ‘g2f’ and ‘exp2flux’) released through the Comprehensive R Archive Network repositories during the development of this work. From our analysis, we predict that tibolone executes their neuroprotective effects through a reduction of neurotoxicity mediated by L-glutamate in astrocytes, inducing the activation several metabolic pathways with neuroprotective actions associated such as taurine metabolism, gluconeogenesis, calcium and the Peroxisome Proliferator Activated Receptor signaling pathways. Also, we found a tibolone associated increase in growth rate probably in concordance with previously reported side effects of steroid compounds in other human cell types.

Keywords: astrocytes, flux balance analysis, genome scale metabolic reconstruction, inflammation, neuroprotection, tibolone

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480 Ordinary Differentiation Equations (ODE) Reconstruction of High-Dimensional Genetic Networks through Game Theory with Application to Dissecting Tree Salt Tolerance

Authors: Libo Jiang, Huan Li, Rongling Wu

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Ordinary differentiation equations (ODE) have proven to be powerful for reconstructing precise and informative gene regulatory networks (GRNs) from dynamic gene expression data. However, joint modeling and analysis of all genes, essential for the systematical characterization of genetic interactions, are challenging due to high dimensionality and a complex pattern of genetic regulation including activation, repression, and antitermination. Here, we address these challenges by unifying variable selection and game theory through ODE. Each gene within a GRN is co-expressed with its partner genes in a way like a game of multiple players, each of which tends to choose an optimal strategy to maximize its “fitness” across the whole network. Based on this unifying theory, we designed and conducted a real experiment to infer salt tolerance-related GRNs for Euphrates poplar, a hero tree that can grow in the saline desert. The pattern and magnitude of interactions between several hub genes within these GRNs were found to determine the capacity of Euphrates poplar to resist to saline stress.

Keywords: gene regulatory network, ordinary differential equation, game theory, LASSO, saline resistance

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479 Microanalysis of a New Cementitious System Containing High Calcium Fly Ash and Waste Material by Scanning Electron Microscopy (SEM)

Authors: Anmar Dulaimi, Hassan Al Nageim, Felicite Ruddock, Linda Seton

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Fast-curing cold bituminous emulsion mixture (CBEM) including active filler from high calcium fly ash (HCFA) and waste material (LJMU-A2) has been developed in this study. This will overcome the difficulties related with the use of hot mix asphalt such as greenhouse gases emissions and problems in keeping the temperature when transporting long distance. The aim of this study is to employ petrographic examinations using scanning electron microscopy (SEM) for characterizing the hydrates microstructure, in a new binary blended cement filler (BBCF) system. The new BBCF has been used as a replacement to traditional mineral filler in cold bituminous emulsion mixtures (CBEMs), comprises supplementary cementitious materials containing high calcium fly ash (HCFA) and a waste material (LJMU-A2). SEM analysis demonstrated the formation of hydrates after varying curing ages within the BBCF. The accelerated activation of HCFA by LJMU-A2 within the BBCF was revealed and as a consequence early and later stiffness was developed in novel CBEM.

Keywords: cold bituminous emulsion mixtures, indirect tensile stiffness modulus, scanning electron microscopy (SEM), and high calcium fly ash

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478 Autophagy Suppresses Tumorigenesis through Upregulation of MiR-449a in Colorectal Cancer

Authors: Sheng-Hui Lan, Shan-Ying Wu, Shu-Ching Lin, Wei-Chen Wang, Hsiao-Sheng Liu

Abstract:

Autophagy is an essential mechanism to maintain cellular homeostasis through its degradation function, and the autophagy deficiency is related various diseases including tumorigenesis in several cancers. MicroRNAs (miRNAs) are small none coding RNAs, which regulate gene expression through degradation of mRNA or inhibition of translation. However, the relationship between autophagy deficiency and dysregulated miRNAs is still unclear. We revealed a mechanism that autophagy up-regulates miR-449a expression at the transcriptional level through activation of forkhead transcription factor family member FoxO1 and then suppresses tumorigenesis in CRC. Our data showed that the autophagic activity and miR-449a expression were lower in colorectal cancer (CRC) and has a positive correlation. We further reveal that autophagy degrades p300 expression and then suppresses acetylation of FoxO1. Under autophagic induction conditions, FoxO1 is transported from the cytoplasm to the nucleus and binds to the miR-449a promoter and then promotes miR-449a expression. In addition, either miR-449a overexpression or amiodarone-induced autophagy inhibits cell cycle progression, proliferation, colony formation migration, invasion, and tumor formation of SW480 cells. Our findings indicate that autophagy inducers may have the potential to be used for prevention and treatment of CRC through upregulation of miR-449a expression.

Keywords: autophagy, MiR-449a, FoxO1, colorectal cancer

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477 Enhanced Biosorption of Copper Ions by Luffa Cylindrica: Biosorbent Characterization and Batch Experiments

Authors: Nouacer Imane, Benalia Mokhtar, Djedid Mabrouk

Abstract:

The adsorption ability of a powdered activated carbons (PAC) derived from Luffa cylindrica investigated in an attempt to produce more economic and effective sorbents for the control of Cu(II) ion from industrial liquid streams. Carbonaceous sorbents derived from local luffa cylindrica, were prepared by chemical activation methods using ZnCl2 as activating reagents. Adsorption of Cu (II) from aqueous solutions was investigated. The effects of pH, initial adsorbent concentration, the effect of particle size, initial metal ion concentration and temperature were studied in batch experiments. The maximum adsorption capacity of copper onto grafted Luffa cylindrica fiber was found to be 14.23 mg/g with best fit for Langmuir adsorption isotherm. The values of thermodynamic parameters such as enthalpy change, ∆H (-0.823 kJ/mol), entropy change, ∆S (-9.35 J/molK) and free energy change, ∆G (−1.56 kJ/mol) were also calculated. Adsorption process was found spontaneous and exothermic in nature. Finally, the luffa cylindrica has been evaluated by FTIR, MO and x-ray diffraction in order to determine if the biosorption process modifies its chemical structure and morphology, respectively. Luffa cylindrica has been proven to be an efficient biomaterial useful for heavy metal separation purposes that is not altered by the process.

Keywords: adsorption, cadmium, isotherms, thermodynamic, luffa sponge

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476 A Study on Energy-Saving Modular Housing Units Considering Environmental and Aesthetic Aspects

Authors: Jae Hee Chung, Tae Uk Kang, Byung Seo Kim

Abstract:

This study aims to propose design technologies for the energy-saving modular housing units considering environmental and aesthetic aspects. Modular houses are environmentally friendly based on 3R (Reduce, Reuse, Recycle) because they can dramatically reduce carbon dioxide and construction wastes generated during the construction, use, and disposal process by the pre-fabrication at the factory and the recyclability of the unit, compared to the existing construction methods. The existing modular housing, however, tends to focus on quantitative aspects of energy reduction, such as windows, insulation, and introduction of renewable energy, and there is not much research on energy-saving type units considering the environmental aspects such as daylighting and ventilation, and the design that goes beyond the standardized appearance. Therefore, this study conducts theoretical investigation and analytical case studies on the energy-saving methods through various architectural planning elements as well as materials like insulation considering the environmental and aesthetic aspects in the modular housing. Then, comparative analysis on the energy efficiency through the energy simulation is conducted. As a conclusion, the energy-saving modular housing units considering environmental and aesthetics aspects are proposed. It is expected that this study will contribute to the supply and activation of modular housing through deriving design technologies for the energy-saving modular housing units that consider not only quantitative aspects but also qualitative aspects.

Keywords: aesthetic aspects, energy-saving, environmental, modular housing

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475 New Quinazoline Derivative Exhibit Cytotoxic Effect agaisnt MCF-7 Human Breast Cancer Cell

Authors: Maryam Zahedifard, Fadhil Lafta Faraj, Nazia Abdul Majid, Hapipah Mohd Ali, Mahmood Ameen Abdulla

Abstract:

The new quinazoline Schiff bases have been synthesized through condensation reaction of 2-aminobenzhydrazide with 5-bromosalicylaldehyde and 3-methoxy-5-bromosalicylaldehyde. The compound was investigated for anticancer activity against MCF-7 human breast cancer cell line. It demonstrated a remarkable antiproliferative effect, with an IC50 value of 3.41±0.34, after 72 hours of treatment. Most apoptosis morphological features in treated MCF-7 cells were observed by AO/PI staining. The results of cell cycle analysis indicate that compounds did not induce S and M phase arrest in cell after 24 hours of treatment. Furthermore, MCF-7 cells treated with compound subjected to apoptosis death, as exhibited by perturbation of mitochondrial membrane potential and cytochrome C release as well as increase in ROS generation. We also found activation of caspases 3/7 and -9. Moreover, acute toxicity results demonstrated the nontoxic nature of the compounds in mice. Our results showed the selected compound significantly induce apoptosis in MCF-7 cells via intrinsic pathway, which might be considered as a potential candidate for further in vivo and clinical breast cancer studies.

Keywords: quinazoline Schiff base, apoptosis, MCF-7, caspase, cell cycle, acute toxicity

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474 TeleEmergency Medicine: Transforming Acute Care through Virtual Technology

Authors: Ashley L. Freeman, Jessica D. Watkins

Abstract:

TeleEmergency Medicine (TeleEM) is an innovative approach leveraging virtual technology to deliver specialized emergency medical care across diverse healthcare settings, including internal acute care and critical access hospitals, remote patient monitoring, and nurse triage escalation, in addition to external emergency departments, skilled nursing facilities, and community health centers. TeleEM represents a significant advancement in the delivery of emergency medical care, providing healthcare professionals the capability to deliver expertise that closely mirrors in-person emergency medicine, exceeding geographical boundaries. Through qualitative research, the extension of timely, high-quality care has proven to address the critical needs of patients in remote and underserved areas. TeleEM’s service design allows for the expansion of existing services and the establishment of new ones in diverse geographic locations. This ensures that healthcare institutions can readily scale and adapt services to evolving community requirements by leveraging on-demand (non-scheduled) telemedicine visits through the deployment of multiple video solutions. In terms of financial management, TeleEM currently employs billing suppression and subscription models to enhance accessibility for a wide range of healthcare facilities. Plans are in motion to transition to a billing system routing charges through a third-party vendor, further enhancing financial management flexibility. To address state licensure concerns, a patient location verification process has been integrated through legal counsel and compliance authorities' guidance. The TeleEM workflow is designed to terminate if the patient is not physically located within licensed regions at the time of the virtual connection, alleviating legal uncertainties. A distinctive and pivotal feature of TeleEM is the introduction of the TeleEmergency Medicine Care Team Assistant (TeleCTA) role. TeleCTAs collaborate closely with TeleEM Physicians, leading to enhanced service activation, streamlined coordination, and workflow and data efficiencies. In the last year, more than 800 TeleEM sessions have been conducted, of which 680 were initiated by internal acute care and critical access hospitals, as evidenced by quantitative research. Without this service, many of these cases would have necessitated patient transfers. Barriers to success were examined through thorough medical record review and data analysis, which identified inaccuracies in documentation leading to activation delays, limitations in billing capabilities, and data distortion, as well as the intricacies of managing varying workflows and device setups. TeleEM represents a transformative advancement in emergency medical care that nurtures collaboration and innovation. Not only has advanced the delivery of emergency medicine care virtual technology through focus group participation with key stakeholders, rigorous attention to legal and financial considerations, and the implementation of robust documentation tools and the TeleCTA role, but it’s also set the stage for overcoming geographic limitations. TeleEM assumes a notable position in the field of telemedicine by enhancing patient outcomes and expanding access to emergency medical care while mitigating licensure risks and ensuring compliant billing.

Keywords: emergency medicine, TeleEM, rural healthcare, telemedicine

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473 Study and Melanocyte Adrenocorticotropic Effects on Sugar Metabolism and Immune Response in Rabbits Oryctolagus cuniculus

Authors: A. Bouaouiche, M. S. Boulakoud

Abstract:

The functioning of the pineal gland, the transducer body of environmental information to the neuroendocrine system is subject to a circadian rhythm. Melatonin is the main neuro-hormone expressing this operation. It is synthesized in the pinealocytes after conversion serotonin via N-acetyl-transferase enzyme, itself subject to a photoperiodic modulation (activation dark inhibition by light). Some authors have suggested that melatonin is involved in diabetic disease and found that it could have a diabetogenic effect. To this study the effect of this hormone on glucose metabolism has long been subject to controversy. Agreeing in effect and hyperinsulinemic hypoglycemic effect. In order to illustrate the level of interaction of melatonin with neuro-immune- corticotropin axis and its impact on carbohydrate metabolism, we studied the impact homeostatic (glucose) through the solicitation of two control systems (gland pineal and corticotropin axis). We then found that melatonin could have an indirect influence on insulin control (glucose metabolism) to the levels of the growth hormone axis (somatostatin) and adrenocorticotropic (corticotropin). In addition, we have suggested that melatonin might limit the hyperglycemic action of corticosteroids by direct action at peripheral level.

Keywords: pinéal gland, melatonin, neuro-immuno-corticotrop, metabolism

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472 Preparation and Characterization of Maltodextrin Microcapsules Containing Walnut Green Husk Extract

Authors: Fatemeh Cheraghali, Saeedeh Shojaee-Aliabadi, Seyede Marzieh Hosseini, Leila Mirmoghtadaie

Abstract:

In recent years, the field of natural antimicrobial and antioxidant compounds is one of the main research topics in the food industry. Application of agricultural residues is mainly cheap, and available resources are receiving increased attention. Walnut green husk is one of the agricultural residues that is considered as natural compounds with biological properties because of phenolic compounds. In this study, maltodextrin 10% was used for microencapsulation of walnut green husk extract. At first, the extract was examined to consider extraction yield, total phenolic compounds, and antioxidant activation. The results showed the extraction yield of 81.43%, total phenolic compounds of 3997 [mg GAE/100 g], antioxidant activity [DPPH] of 84.85% for walnut green husk extract. Antioxidant activity is about 75%-81% and by DPPH. At the next stage, microencapsulation was done by spry-drying method. The microencapsulation efficiency was 72%-79%. The results of SEM tests confirmed this microencapsulation process. In addition, microencapsulated and free extract was more effective on gram-positive bacteria’s rather than the gram-negative ones. According to the study, walnut green husk can be used as a cheap antioxidant and antimicrobial compounds due to sufficient value of phenolic compounds.

Keywords: biopolymer, microencapsulation, spray-drying, walnut green husk

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471 Dielectric Spectroscopy Investigation of Hydrophobic Silica Aerogel

Authors: Deniz Bozoglu, Deniz Deger, Kemal Ulutas, Sahin Yakut

Abstract:

In recent years, silica aerogels have attracted great attention due to their outstanding properties, and their wide variety of potential applications such as microelectronics, nuclear and high-energy physics, optics and acoustics, superconductivity, space-physics. Hydrophobic silica aerogels were successfully synthesized in one-step by surface modification at ambient pressure. FT-IR result confirmed that Si-OH groups were successfully converted into hydrophobic and non-polar Si-CH3 groups by surface modification using trimethylchloro silane (TMCS) as co-precursor. Using Alpha-A High-Resolution Dielectric, Conductivity and Impedance Analyzer, AC conductivity of samples were examined at temperature range 293-423 K and measured over frequency range between 1-106 Hz. The characteristic relaxation time decreases with increasing temperature. The AC conductivity follows σ_AC (ω)=σ_t-σ_DC=Aω^s relation at frequencies higher than 10 Hz, and the dominant conduction mechanism is found to obey the Correlated Barrier Hopping (CBH) mechanism. At frequencies lower than 10 Hz, the electrical conduction is found to be in accordance with DC conduction mechanism. The activation energies obtained from AC conductivity results and it was observed two relaxation regions.

Keywords: aerogel, synthesis, dielectric constant, dielectric loss, relaxation time

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470 Intensive Crosstalk between Autophagy and Intracellular Signaling Regulates Osteosarcoma Cell Survival Response under Cisplatin Stress

Authors: Jyothi Nagraj, Sudeshna Mukherjee, Rajdeep Chowdhury

Abstract:

Autophagy has recently been linked with cancer cell survival post drug insult contributing to acquisition of resistance. However, the molecular signaling governing autophagic survival response is poorly explored. In our study, in osteosarcoma (OS) cells cisplatin shock was found to activate both MAPK and autophagy signaling. An activation of JNK and autophagy acted as pro-survival strategy, while ERK1/2 triggered apoptotic signals upon cisplatin stress. An increased sensitivity of the cells to cisplatin was obtained with simultaneous inhibition of both autophagy and JNK pathway. Furthermore, we observed that the autophagic stimulation upon drug stress regulates other developmentally active signaling pathways like the Hippo pathway in OS cells. Cisplatin resistant cells were thereafter developed by repetitive drug exposure followed by clonal selection. Basal levels of autophagy were found to be high in resistant cells to. However, the signaling mechanism leading to autophagic up-regulation and its regulatory effect differed in OS cells upon attaining drug resistance. Our results provide valuable clues to regulatory dynamics of autophagy that can be considered for development of improved therapeutic strategy against resistant type cancers.

Keywords: JNK, autophagy, drug resistance, cancer

Procedia PDF Downloads 270