Search results for: A2780 and its resistant cells
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4111

Search results for: A2780 and its resistant cells

3451 Precursor Muscle Cell’s Phenotype under Compression in a Biomimetic Mechanical Niche

Authors: Fatemeh Abbasi, Arne Hofemeier, Timo Betz

Abstract:

Muscle growth and regeneration critically depend on satellite cells (SCs) which are muscle stem cells located between the basal lamina and myofibres. Upon damage, SCs become activated, enter the cell cycle, and give rise to myoblasts that form new myofibres, while a sub-population self-renew and re-populate the muscle stem cell niche. In aged muscle as well as in certain muscle diseases such as muscular dystrophy, some of the SCs lose their regenerative ability. Although it is demonstrated that the chemical composition of SCs quiescent niche is different from the activated niche, the mechanism initially activated in the SCs remains unknown. While extensive research efforts focused on potential chemical activation, no such factor has been identified to the author’s best knowledge. However, it is substantiated that niche mechanics affects SCs behaviors, such as stemness and engraftment. We hypothesize that mechanical stress in the healthy niche (homeostasis) is different from the regenerative niche and that this difference could serve as an early signal activating SCs upon fiber damage. To investigate this hypothesis, we develop a biomimetic system to reconstitute both, the mechanical and the chemical environment of the SC niche. Cells will be confined between two elastic polyacrylamide (PAA) hydrogels with controlled elastic moduli and functionalized surface chemistry. By controlling the distance between the PAA hydrogel surfaces, we vary the compression forces exerted by the substrates on the cells, while the lateral displacement of the upper hydrogel will create controlled shear forces. To establish such a system, a simplified system is presented. We engineered a sandwich-like configuration of two elastic PAA layer with stiffnesses between 1 and 10 kPa and confined a precursor myoblast cell line (C2C12) in between these layers. Our initial observations in this sandwich model indicate that C2C12 cells show different behaviors under mechanical compression if compared to a control one-layer gel without compression. Interestingly, this behavior is stiffness-dependent. While the shape of C2C12 cells in the sandwich consisting of two stiff (10 kPa) layers was much more elongated, showing almost a neuronal phenotype, the cell shape in a sandwich situation consisting of one stiff and one soft (1 kPa) layer was more spherical. Surprisingly, even in proliferation medium and at very low cell density, the sandwich situation stimulated cell differentiation with increased striation and myofibre formation. Such behavior is commonly found for confluent cells in differentiation medium. These results suggest that mechanical changes in stiffness and applied pressure might be a relevant stimulation for changes in muscle cell behavior.

Keywords: C2C12 cells, compression, force, satellite cells, skeletal muscle

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3450 The Retinoprotective Effects and Mechanisms of Fungal Ingredient 3,4-Dihydroxybenzalacetone through Inhibition of Retinal Müller and Microglial Activation

Authors: Yu-Wen Cheng, Jau-Der Ho, Liang-Huan Wu, Fan-Li Lin, Li-Huei Chen, Hung-Ming Chang, Yueh-Hsiung Kuo, George Hsiao

Abstract:

Retina glial activation and neuroinflammation have been confirmed to cause devastating responses in retinodegenerative diseases. The expression and activation of matrix metalloproteinase (MMP)-9 and inducible nitric oxide synthase (iNOS) could be exerted as the crucial pathological factors in glaucoma- and blue light-induced retinal injuries. The present study aimed to investigate the retinoprotective effects and mechanisms of fungal ingredient 3,4-dihydroxybenzalacetone (DBL) isolated from Phellinus linteus in the retinal glial activation and retinodegenerative animal models. According to the cellular studies, DBL significantly and concentration-dependently abrogated MMP-9 activation and expression in TNFα-stimulated retinal Müller (rMC-1) cells. We found the inhibitory activities of DBL were strongly through the STAT- and ERK-dependent pathways. Furthermore, DBL dramatically attenuated MMP-9 activation in the stimulated Müller cells exposed to conditioned media from LPS-stimulated microglia BV-2 cells. On the other hand, DBL strongly suppressed LPS-induced production of NO and ROS and expression of iNOS in microglia BV-2 cells. Consistently, the phosphorylation of STAT was substantially blocked by DBL in LPS-stimulated microglia BV-2 cells. In the evaluation of retinoprotective functions, the high IOP-induced scotopic electroretinographic (ERG) deficit and blue light-induced abnormal pupillary light response (PLR) were assessed. The deficit scotopic ERG responses markedly recovered by DBL in a rat model of glaucoma-like ischemia/reperfusion (I/R)-injury. DBL also reduced the aqueous gelatinolytic activity and retinal MMP-9 expression in high IOP-injured conditions. Additionally, DBL could restore the abnormal PLR and reduce retinal MMP-9 activation. In summary, DBL could ameliorate retinal neuroinflammation and MMP-9 activation by predominantly inhibiting STAT3 activation in the retinal Müller cells and microglia, which exhibits therapeutic potential for glaucoma and other retinal degenerative diseases.

Keywords: glaucoma, blue light, DBL, retinal Müller cell, MMP-9, STAT, Microglia, iNOS, ERG, PLR

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3449 Numerical Model for Investigation of Recombination Mechanisms in Graphene-Bonded Perovskite Solar Cells

Authors: Amir Sharifi Miavaghi

Abstract:

It is believed recombination mechnisms in graphene-bonded perovskite solar cells based on numerical model in which doped-graphene structures are employed as anode/cathode bonding semiconductor. Moreover, th‌‌‌‌e da‌‌‌‌‌rk-li‌‌‌‌‌ght c‌‌‌‌urrent d‌‌‌‌ens‌‌‌‌ity-vo‌‌‌‌‌‌‌ltage density-voltage cu‌‌‌‌‌‌‌‌‌‌‌rves are investigated by regression analysis. L‌‌‌oss m‌‌‌‌echa‌‌‌‌nisms suc‌‌‌h a‌‌‌‌‌‌s ba‌‌‌‌ck c‌‌‌ontact b‌‌‌‌‌arrier, d‌‌‌‌eep surface defect i‌‌‌‌n t‌‌‌‌‌‌‌he adsorbent la‌‌‌yer is det‌‌‌‌‌ermined b‌‌‌y adapting th‌‌‌e sim‌‌‌‌‌ulated ce‌‌‌‌‌ll perfor‌‌‌‌‌mance to t‌‌‌‌he measure‌‌‌‌ments us‌‌‌‌ing the diffe‌‌‌‌‌‌rential evolu‌‌‌‌‌tion of th‌‌‌‌e global optimization algorithm. T‌‌‌‌he performance of t‌‌‌he c‌‌‌‌ell i‌‌‌‌n the connection proc‌‌‌‌‌ess incl‌‌‌‌‌‌udes J-V cur‌‌‌‌‌‌ves that are examined at di‌‌‌‌‌fferent tempe‌‌‌‌‌‌‌ratures an‌‌‌d op‌‌‌‌en cir‌‌‌‌cuit vol‌‌‌‌tage (V) und‌‌‌‌er differ‌‌‌‌‌ent light intensities as a function of temperature. Ba‌‌‌‌sed o‌‌‌n t‌‌‌he prop‌‌‌‌osed nu‌‌‌‌‌merical mod‌‌‌‌el a‌‌‌‌nd the acquired lo‌‌‌‌ss mecha‌‌‌‌‌‌nisms, our approach can be used to improve the efficiency of the solar cell further. Due to the high demand for alternative energy sources, solar cells are good alternatives for energy storage using the photovoltaic phenomenon.

Keywords: numerical model, recombination mechanism, graphen, perovskite solarcell

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3448 iPSCs More Effectively Differentiate into Neurons on PLA Scaffolds with High Adhesive Properties for Primary Neuronal Cells

Authors: Azieva A. M., Yastremsky E. V., Kirillova D. A., Patsaev T. D., Sharikov R. V., Kamyshinsky R. A., Lukanina K. I., Sharikova N. A., Grigoriev T. E., Vasiliev A. L.

Abstract:

Adhesive properties of scaffolds, which predominantly depend on the chemical and structural features of their surface, play the most important role in tissue engineering. The basic requirements for such scaffolds are biocompatibility, biodegradation, high cell adhesion, which promotes cell proliferation and differentiation. In many cases, synthetic polymers scaffolds have proven advantageous because they are easy to shape, they are tough, and they have high tensile properties. The regeneration of nerve tissue still remains a big challenge for medicine, and neural stem cells provide promising therapeutic potential for cell replacement therapy. However, experiments with stem cells have their limitations, such as low level of cell viability and poor control of cell differentiation. Whereas the study of already differentiated neuronal cell culture obtained from newborn mouse brain is limited only to cell adhesion. The growth and implantation of neuronal culture requires proper scaffolds. Moreover, the polymer scaffolds implants with neuronal cells could demand specific morphology. To date, it has been proposed to use numerous synthetic polymers for these purposes, including polystyrene, polylactic acid (PLA), polyglycolic acid, and polylactide-glycolic acid. Tissue regeneration experiments demonstrated good biocompatibility of PLA scaffolds, despite the hydrophobic nature of the compound. Problem with poor wettability of the PLA scaffold surface could be overcome in several ways: the surface can be pre-treated by poly-D-lysine or polyethyleneimine peptides; roughness and hydrophilicity of PLA surface could be increased by plasma treatment, or PLA could be combined with natural fibers, such as collagen or chitosan. This work presents a study of adhesion of both induced pluripotent stem cells (iPSCs) and mouse primary neuronal cell culture on the polylactide scaffolds of various types: oriented and non-oriented fibrous nonwoven materials and sponges – with and without the effect of plasma treatment and composites with collagen and chitosan. To evaluate the effect of different types of PLA scaffolds on the neuronal differentiation of iPSCs, we assess the expression of NeuN in differentiated cells through immunostaining. iPSCs more effectively differentiate into neurons on PLA scaffolds with high adhesive properties for primary neuronal cells.

Keywords: PLA scaffold, neurons, neuronal differentiation, stem cells, polylactid

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3447 Standardization of a Methodology for Quantification of Antimicrobials Used for the Treatment of Multi-Resistant Bacteria Using Two Types of Biosensors and Production of Anti-Antimicrobial Antibodies

Authors: Garzon V., Bustos R., Salvador J. P., Marco M. P., Pinacho D. G.

Abstract:

Bacterial resistance to antimicrobial treatment has increased significantly in recent years, making it a public health problem. Large numbers of bacteria are resistant to all or nearly all known antimicrobials, creating the need for the development of new types of antimicrobials or the use of “last line” antimicrobial drug therapies for the treatment of multi-resistant bacteria. Some of the chemical groups of antimicrobials most used for the treatment of infections caused by multiresistant bacteria in the clinic are Glycopeptide (Vancomycin), Polymyxin (Colistin), Lipopeptide (Daptomycin) and Carbapenem (Meropenem). Molecules that require therapeutic drug monitoring (TDM). Due to the above, a methodology based on nanobiotechnology based on an optical and electrochemical biosensor is being developed, which allows the evaluation of the plasmatic levels of some antimicrobials such as glycopeptide, polymyxin, lipopeptide and carbapenem quickly, at a low cost, with a high specificity and sensitivity and that can be implemented in the future in public and private health hospitals. For this, the project was divided into five steps i) Design of specific anti-drug antibodies, produced in rabbits for each of the types of antimicrobials, evaluating the results by means of an immunoassay analysis (ELISA); ii) quantification by means of an electrochemical biosensor that allows quantification with high sensitivity and selectivity of the reference antimicrobials; iii) Comparison of antimicrobial quantification with an optical type biosensor; iv) Validation of the methodologies used with biosensor by means of an immunoassay. Finding as a result that it is possible to quantify antibiotics by means of the optical and electrochemical biosensor at concentrations on average of 1,000ng/mL, the antibodies being sensitive and specific for each of the antibiotic molecules, results that were compared with immunoassays and HPLC chromatography. Thus, contributing to the safe use of these drugs commonly used in clinical practice and new antimicrobial drugs.

Keywords: antibiotics, electrochemical biosensor, optical biosensor, therapeutic drug monitoring

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3446 Phylogenetic Analysis of Klebsiella Species from Clinical Specimens from Nelson Mandela Academic Hospital in Mthatha, South Africa

Authors: Sandeep Vasaikar, Lary Obi

Abstract:

Rapid and discriminative genotyping methods are useful for determining the clonality of the isolates in nosocomial or household outbreaks. Multilocus sequence typing (MLST) is a nucleotide sequence-based approach for characterising bacterial isolates. The genetic diversity and the clinical relevance of the drug-resistant Klebsiella isolates from Mthatha are largely unknown. For this reason, prospective, experimental study of the molecular epidemiology of Klebsiella isolates from patients being treated in Mthatha over a three-year period was analysed. Methodology: PCR amplification and sequencing of the drug-resistance-associated genes, and multilocus sequence typing (MLST) using 7 housekeeping genes mdh, pgi, infB, FusAR, phoE, gapA and rpoB were conducted. A total of 32 isolates were analysed. Results: The percentages of multidrug-resistant (MDR), extensively drug-resistance (XDR) and pandrug-resistant (PDR) isolates were; MDR 65.6 % (21) and XDR and PDR with 0 % each. In this study, K. pneumoniae was 19/32 (59.4 %). MLST results showed 22 sequence types (STs) were identified, which were further separated by Maximum Parsimony into 10 clonal complexes and 12 singletons. The most dominant group was Klebsiella pneumoniae with 23/32 (71.8 %) isolates, Klebsiella oxytoca as a second group with 2/32 (6.25 %) isolates, and a single (3.1 %) K. varricola as a third group while 6 isolates were of unknown sequences. Conclusions/significance: A phylogenetic analysis of the concatenated sequences of the 7 housekeeping genes showed that strains of K. pneumoniae form a distinct lineage within the genus Klebsiella, with K. oxytoca and K. varricola its nearest phylogenetic neighbours. With the analysis of 7 genes were determined 1 K. variicola, which was mistakenly identified as K. pneumoniae by phenotypic methods. Two misidentifications of K. oxytoca were found when phenotypic methods were used. No significant differences were observed between ESBL blaCTX-M, blaTEM and blaSHV groups in the distribution of Sequence types (STs) or Clonal complexes (CCs).

Keywords: phylogenetic analysis, phylogeny, klebsiella phylogenetic, klebsiella

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3445 In vitro Cytotoxicity Study on Silver Powders Synthesized via Different Routes

Authors: Otilia Ruxandra Vasile, Ecaterina Andronescu, Cristina Daniela Ghitulica, Bogdan Stefan Vasile, Roxana Trusca, Eugeniu Vasile, Alina Maria Holban, Carmen Mariana Chifiriuc, Florin Iordache, Horia Maniu

Abstract:

Engineered powders offer great promise in several applications, but little information is known about cytotoxicity effects. The aim of the current study was the synthesis and cytotoxicity examination of silver powders using pyrosol method at temperatures of 600°C, 650°C and 700°C, respectively sol-gel method and calcinations at 500°C, 600°C, 700°C and 800°C. We have chosen to synthesize and examine silver particles cytotoxicity due to its use in biological applications. The synthesized Ag powders were characterized from the structural, compositional and morphological point of view by using XRD, SEM, and TEM with SAED. In order to determine the influence of the synthesis route on Ag particles cytotoxicity, different sizes of micro and nanosilver synthesized powders were evaluated for their potential toxicity. For the study of their cytotoxicity, cell cycle and apoptosis have been done analysis through flow cytometry on human colon carcinoma cells and mesenchymal stem cells and through the MTT assay, while the viability and the morphological changes of the cells have been evaluated by using cloning studies. The results showed that the synthesized silver nanoparticles have displayed significant cytotoxicity effects on cell cultures. Our synthesized silver powders were found to present toxicity in a synthesis route and time-dependent manners for pyrosol synthesized nanoparticles; whereas a lower cytotoxicity has been measured after cells were treated with silver nanoparticles synthesized through sol-gel method.

Keywords: Ag, cytotoxicity, pyrosol method, sol-gel method

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3444 Bioactive Molecules Isolated for the First Time from Hyoscyamus albus L. and their Mechanisms Underlying the Anticancer Effects

Authors: Benhouda Afaf, Yahia Massinissa, Paolo Grieco

Abstract:

Hyoscyamus albus L. is a small genus from Solanaceae family known by its use in old traditional medicine in the east of Algeria. Aim: This study aimed to characterize bioactive molecules from H. albus, evaluate their anticancer activity in several cancer cells and investigate their possible molecular mechanism. Materials and Methods: Different compounds (Peak h of fraction F), (Peak 3 of Fraction F), (Peak 1 of fraction C) were isolated from H.albus L by using high-performance chromatography (HPLC), mass spectrometry (MS) and proton NMR (NMR H1). All isolated compounds were subjected to cytotoxicity and antiproliferative assays against a panel of the four cell lines: DU-145, U-2 OS, U-87 MG and LN-229 cell lines and were determined using MTT assay, Annexin V and propodium iodide were used to evaluate apoptosis. Results: The phytochemical study of H. albus Fractions led to the isolation of quercetin-3-O-β-dglucopyranosyl-( 1 → 6)-β-d-glucopyranosid, N-trans-feruloyltyramine, Hydrocaffeoyl-N8- caffeoylspermidine.The biological results indicated that all cell lines were consistently sensitive to P1 FC in a dose-dependent manner. This difference in cytotoxic sensitivity was more pronounced in osteosarcoma cell line, U-2 OS, when compared to prostate cancer and U-87 MG. Cell viability data also demonstrated that only U-87 MG cells were responsive to treatment with Ph FF. compounds P1 FC and Ph FF have induced necrosis and apoptosis in a large part of LN-229 cells. Conclusion: The overall results of the present study provided evidence that isolated compounds are potential therapeutic entities against cancer.

Keywords: hyoscyamus albus, cancer cells, coumpounds, HPLC

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3443 Electrodeposition of NiO Films from Organic Solvent-Based Electrolytic Solutions for Solar Cell Application

Authors: Thierry Pauporté, Sana Koussi, Fabrice Odobel

Abstract:

The preparation of semiconductor oxide layers and structures by soft techniques is an important field of research. Higher performances are expected from the optimizing of the oxide films and then use of new methods of preparation for a better control of their chemical, morphological, electrical and optical properties. We present the preparation of NiO by electrodeposition from pure polar aprotic medium and mixtures with water. The effect of the solvent, of the electrochemical deposition parameters and post-deposition annealing treatment on the structural, morphological and optical properties of the films is investigated. We remarkably show that the solvent is inserted in the deposited layer and act as a blowing agent, giving rise to mesoporous films after elimination by thermal annealing. These layers of p-type oxide have been successfully used, after sensitization by a dye, in p-type dye-sensitized solar cells. The effects of the solvent on the layer properties and the application of these layers in p-type dye-sensitized solar cells are described.

Keywords: NiO, layer, p-type sensitized solar cells, electrodeposition

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3442 Prevalence of Multidrug-resistant Escherichia coli Isolated from Ready to Eat: Crispy Fried Chicken in Jember, Indonesia

Authors: Enny Suswati, Supangat Supangat

Abstract:

Background. Ready-to-eat food products are becoming increasingly popular because consumers are increasingly busy, competitive, and changing lifestyles. Examples of ready-to-eat foods include crispy fried chicken. Escherichia coli is one of the most important causes of food-borne diseases and the most frequent antibiotic-resistant pathogen globally. This study assessed the prevalence and antibiotic resistance profile of E. coli from ready-to-eat crispy fried chicken in Jember city, Indonesia. Methodology. This cross-sectional study was conducted from November 2020 to April 2021 by collecting 81crispy fried chicken samples from 27 food stalls in campus area using a simple random sampling method. Isolation and determination of E. coli use were performed by conventional culture method. An antibiotic susceptibility test was conducted using Kirby Bauer disk diffusion method on the Mueller–Hinton agar. Result. Out of 81crispy fried chicken samples, 77 (95.06%) were positive for E. coli. High E. coli drug resistance was observed on ampicillin, amoxicillin (100%) followed by cefixime (98.72%), erythromycin (97.59%), sulfamethoxazole (93.59%), azithromicin (83.33%), cefotaxime (78.28%), choramphenicol (75.64%), and cefixime (74.36%). On the other hand, there was the highest susceptibility for ciprofloxacin (64.10%). The multiple antibiotic resistance indexes of E. coli isolates varied from 0.4 to 1. The predominant antimicrobial resistance profiles of E. coli were CfmCroAmlAmpAzmCtxSxtCE (n=17), CfmCroAmlCipAmpAzmCtxSxtCE (n=16), and CfmAmlAmpAzmCtxSxtCE (n=5), respectively. Multidrug resistance was also found in the isolates' 76/77 (98.70%). Conclusion. The resistance pattern CfmCroAmlAmpAzmCtxSxtCE was the most common among the E. coli isolates, with 17 showing it. The multiple antibiotic index (MAR index) ranged from 0.4 to 1. Hygienic measures should be rigorously implemented and monitoring resistance of E. coli is required to reduce the risks related to the emergence of multi-resistant bacteria

Keywords: antibacterial drug, ready to eat, crispy fried chicken, escherichia coli

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3441 Fabrication of Silicon Solar Cells Using All Sputtering Process

Authors: Ching-Hua Li, Sheng-Hui Chen

Abstract:

Sputtering is a popular technique with many advantages for thin film deposition. To fabricate a hydrogenated silicon thin film using sputtering process for solar cell applications, the ion bombardment during sputtering will generate microstructures (voids and columnar structures) to form silicon dihydride bodings as defects. The properties of heterojunction silicon solar cells were studied by using boron grains and silicon-boron targets. Finally, an 11.7% efficiency of solar cell was achieved by using all sputtering process.

Keywords: solar cell, sputtering process, pvd, alloy target

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3440 Design of a Controlled BHJ Solar Cell Using Modified Organic Vapor Spray Deposition Technique

Authors: F. Stephen Joe, V. Sathya Narayanan, V. R. Sanal Kumar

Abstract:

A comprehensive review of the literature on photovoltaic cells has been carried out for exploring the better options for cost efficient technologies for future solar cell applications. Literature review reveals that the Bulk Heterojunction (BHJ) Polymer Solar cells offer special opportunities as renewable energy resources. It is evident from the previous studies that the device fabricated with TiOx layer shows better power conversion efficiency than that of the device without TiOx layer. In this paper, authors designed a controlled BHJ solar cell using a modified organic vapor spray deposition technique facilitated with a vertical-moving gun named as 'Stephen Joe Technique' for getting a desirable surface pattern over the substrate to improving its efficiency over the years for industrial applications. We comprehended that the efficient processing and the interface engineering of these solar cells could increase the efficiency up to 5-10 %.

Keywords: BHJ polymer solar cell, photovoltaic cell, solar cell, Stephen Joe technique

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3439 Effect of Far Infrared and Endothelial Cell Growth Supplement on Human Umbilical Vascular Endothelial Cells

Authors: Ming-Tzu Tsai, Jui-Ting Hsu, Chia-Chieh Lin, Feng-Tsai Chiang, Cheng-Chin Huang

Abstract:

Far infrared (FIR), an invisible and short electromagnetic waves ranges from 6-14 μm also defines as the “growth ray.” Although the mechanism of FIR is still unknown, most data have suggested that FIR could accelerate the skin microcirculation by elevating the blood flow and nitric-oxide (NO) synthesis. In this present work, the effect of FIR irradiation and endothelial cell growth supplement (ECGS) on human umbilical vascular endothelial cells (HUVECs) was evaluated. To understand whether the cell viability and NO production of HUVECs affected by NO, cells with/without ECGS were treated in the presence or absence of L-NAME, an eNOS inhibitor. For FIR exposure, FIR-emitted ceramic powders consisted of a variety of well-mixed metal oxides were developed. The results showed that L-NAME did had a strong effect on the inhibition of NO production, especially in the ECGS-treated group. However, the cell viability of each group was rarely affected in the presence of L-NAME. Cells with the incubation of ECGS showed much higher cell viability compared to the control. Moreover, NO production of HUVECs exposed to FIR irradiation was significantly inhibited in the presence of L-NAME. It suggested that NO could play a role modulating the downstream signals of HUVECs during FIR exposure.

Keywords: far-infrared irradiation (FIR), nitric oxide (NO), endothelial nitric oxide synthase (eNOS), endothelial cell growth supplement (ECGS)

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3438 Suppression of Immunostimulatory Function of Dendritic Cells and Prolongation of Skin Allograft Survival by Dryocrassin

Authors: Hsin-Lien Lin, Ju-Hui Fu

Abstract:

Dendritic cells (DCs) are the major professional antigen-presenting cells for the development of optimal T-cell immunity. DCs can be used as pharmacological targets to screen novel biological modifiers for the treatment of harmful immune responses, such as transplantation rejection. Dryopteris crassirhizoma Nakai (Aspiadaceae) is used for traditional herbal medicine in the region of East Asia. The root of this fern plant has been listed for treating inflammatory diseases. Dryocrassin is the tetrameric phlorophenone component derived from Dryopteris. Here, we tested the immunomodulatory potential of dryocrassin on lipopolysaccharide (LPS)-stimulated activation of mouse bone marrow-derived DCs in vitro and in skin allograft transplantation in vivo. Results demonstrated that dryocrassin reduced the secretion of tumor necrosis factor-α, interleukin-6, and interleukin-12p70 by LPS-stimulated DCs. The expression of LPS-induced major histocompatibility complex class II, CD40, and CD86 on DCs was also blocked by dryocrassin. Moreover, LPS-stimulated DC-elicited allogeneic T-cell proliferation was lessened by dryocrassin. In addition, dryocrassin inhibited LPS-induced activation of IϰB kinase, JNK/p38 mitogen-activated protein kinase, as well as the translocation of NF-ϰB. Treatment with dryocrassin obviously diminished 2,4-dinitro-1-fluorobenzene- induced delayed-type hypersensitivity and prolonged skin allograft survival. Dryocrassin may be one of the potent immunosuppressive agents for transplant rejection through the destruction of DC maturation and function.

Keywords: dryocrassin, dendritic cells, immunosuppression, skin allograft

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3437 Hydrogel Based on Cellulose Acetate Used as Scaffold for Cell Growth

Authors: A. Maria G. Melero, A. M. Senna, J. A. Domingues, M. A. Hausen, E. Aparecida R. Duek, V. R. Botaro

Abstract:

A hydrogel from cellulose acetate cross linked with ethylenediaminetetraacetic dianhydride (HAC-EDTA) was synthesized by our research group, and submitted to characterization and biological tests. Cytocompatibility analysis was performed by confocal microscopy using human adipocyte derived stem cells (ASCs). The FTIR analysis showed characteristic bands of cellulose acetate and hydroxyl groups and the tensile tests evidence that HAC-EDTA present a Young’s modulus of 643.7 MPa. The confocal analysis revealed that there was cell growth at the surface of HAC-EDTA. After one day of culture the cells presented spherical morphology, which may be caused by stress of the sequestration of Ca2+ and Mg2+ ions at the cell medium by HAC-EDTA, as demonstrated by ICP-MS. However, after seven days and 14 days of culture, the cells present fibroblastoid morphology, phenotype expected by this cellular type. The results give efforts to indicate this new material as a potential biomaterial for tissue engineering, in the future in vivo approach.

Keywords: cellulose acetate, hydrogel, biomaterial, cellular growth

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3436 Energy Management Method in DC Microgrid Based on the Equivalent Hydrogen Consumption Minimum Strategy

Authors: Ying Han, Weirong Chen, Qi Li

Abstract:

An energy management method based on equivalent hydrogen consumption minimum strategy is proposed in this paper aiming at the direct-current (DC) microgrid consisting of photovoltaic cells, fuel cells, energy storage devices, converters and DC loads. The rational allocation of fuel cells and battery devices is achieved by adopting equivalent minimum hydrogen consumption strategy with the full use of power generated by photovoltaic cells. Considering the balance of the battery’s state of charge (SOC), the optimal power of the battery under different SOC conditions is obtained and the reference output power of the fuel cell is calculated. And then a droop control method based on time-varying droop coefficient is proposed to realize the automatic charge and discharge control of the battery, balance the system power and maintain the bus voltage. The proposed control strategy is verified by RT-LAB hardware-in-the-loop simulation platform. The simulation results show that the designed control algorithm can realize the rational allocation of DC micro-grid energy and improve the stability of system.

Keywords: DC microgrid, equivalent minimum hydrogen consumption strategy, energy management, time-varying droop coefficient, droop control

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3435 In Vitro Antibacterial Activity of Some Medicinal Plants Against Biofilm-Forming Methicillin-Resistant Staphylococcus aureus

Authors: Tesleem Adewale Ibrahim

Abstract:

Introduction: The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) has been slowly rising in Nigeria for the past few decades. Therefore, novel classes of antibiotics are indispensable to combat the increased incidence of newly emerging multidrug-resistant bacteria like MRSA. Plants have been commonly used in popular medicine of most cultures for the treatment of disease. The in vitro antibacterial activity of some Nigerian common medicinal plants used in traditional medicine has been reported. The aim of this study was to investigate the antibacterial and anti-biofilm of these native plants (Entada abysinnica (leaves), Croton macrostachyus (leaves), Bridelia speciosa (seeds, bark), and Aframomum melegueta (leaves, seeds, and stem) collected in Southwestern Nigeria against a panel of seven biofilm-forming MRSA. Methods: Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the plant extracts against MRSA were determined by the broth dilution method, and the anti-biofilm assay of the most potent plant extract was performed. Result: The results revealed that, of the four plants, water extracts of leaves of Entada abysinnica, leaves of Croton macrostachyus, seeds and bark Bridelia speciosa, and seeds of Aframomum melegueta exhibited significant antibacterial activity. Based on the MIC/MBC ratio, the extracts of these plants were determined to be bacteriostatic in nature. Anti-biofilm assay showed that the extract of seeds of Aframomum melegueta and leaves of Croton macrostachyus fairly inhibited the growth of MRSA in the preformed biofilm matrix. Conclusion: These four medicinal plant species may represent a source of alternative drugs derived from plant extracts based on folklore use and ethnobotanical knowledge from southwest Nigeria.

Keywords: extract, MRSA, antibacterial, biofilm, medicinal plants

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3434 Development of Cationic Gelatin Nanoparticles as an Antigen-Carrier for Mucosal Immunization

Authors: Ping-Lun Jiang, Hung-Jun Lin, Shen-Fu Lin, Mei-Yin Chien, Ting-Wei Li, Chun-Han Lin, Der-Zen Liu

Abstract:

Mucosal vaccine induces both mucosal (secretory IgA) and systemic immune responses and it is considered an ideal vaccination strategy for prevention of infectious diseases. One important point to be considered in mucosal vaccination is effective antigen delivery system which can manage effective delivery of antigen to antigen-presenting cells (APCs) of mucosal. In the present study, cationic gelatin nanoparticles were prepared as ideal carriers for more efficient antigen delivery. The average diameter of cationic gelatin nanoparticle was approximate 190 nm, and the zeta potential was about +45 mV, then ovalbumin (OVA) was physically absorbed onto cationic gelatin nanoparticle. The OVA absorption rate was near 95% the zeta potential was about +20 mV. We show that cationic gelatin nanoparticle effectively facilitated antigen uptake by mice bone marrow-derived dendritic cells (mBMDCs) and RAW264.7 cells and induced higher levels of pro-inflammatory cytokines. C57BL/6 mice twice immunized intranasally with OVA-absorbed cationic gelatin nanoparticle induced high levels of OVA-specific IgG in the serum and IgA in their in the nasal and lung wash fluid. These results indicate that nasal administration of cationic gelatin nanoparticles induced both mucosal and systemic immune responses and cationic gelatin nanoparticles might be a potential antigen delivery carrier for further clinical applications.

Keywords: antigen delivery, antigen-presenting cells, gelatin nanoparticle, mucosal vaccine

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3433 Towards a Biologically Relevant Tumor-on-a-Chip: Multiplex Microfluidic Platform to Study Breast Cancer Drug Response

Authors: Soroosh Torabi, Brad Berron, Ren Xu, Christine Trinkle

Abstract:

Microfluidics integrated with 3D cell culture is a powerful technology to mimic cellular environment, and can be used to study cell activities such as proliferation, migration and response to drugs. This technology has gained more attention in cancer studies over the past years, and many organ-on-a-chip systems have been developed to study cancer cell behaviors in an ex-vivo tumor microenvironment. However, there are still some barriers to adoption which include low throughput, complexity in 3D cell culture integration and limitations on non-optical analysis of cells. In this study, a user-friendly microfluidic multi-well plate was developed to mimic the in vivo tumor microenvironment. The microfluidic platform feeds multiple 3D cell culture sites at the same time which enhances the throughput of the system. The platform uses hydrophobic Cassie-Baxter surfaces created by microchannels to enable convenient loading of hydrogel/cell suspensions into the device, while providing barrier free placement of the hydrogel and cells adjacent to the fluidic path. The microchannels support convective flow and diffusion of nutrients to the cells and a removable lid is used to enable further chemical and physiological analysis on the cells. Different breast cancer cell lines were cultured in the device and then monitored to characterize nutrient delivery to the cells as well as cell invasion and proliferation. In addition, the drug response of breast cancer cell lines cultured in the device was compared to the response in xenograft models to the same drugs to analyze relevance of this platform for use in future drug-response studies.

Keywords: microfluidics, multi-well 3d cell culture, tumor microenvironment, tumor-on-a-chip

Procedia PDF Downloads 264
3432 Improving Physicochemical Properties of Milk Powder and Lactose-Free Milk Powder with the Prebiotic Carrier

Authors: Chanunya Fahwan, Supat Chaiyakul

Abstract:

A lactose-free diet is imperative for those with lactose intolerance and experiencing milk intolerance. This entails eliminating milk-based products, which may result in dietary and nutritional challenges and the main problems of Lactose hydrolyzed milk powder during production were the adhesion in the drying chamber and low-yield and low-quality powder. The use of lactose-free milk to produce lactose-free milk powder was studied here. Development of two milk powder formulas from cow's milk and lactose-free cow's milk by using a substitute for maltodextrin, Polydextrose (PDX), Resistant Starch (RS), Cellobiose (CB), and Resistant Maltodextrin (RMD) to improve quality and reduce the glycemic index from maltodextrin, which are carriers that were used in industry at three experimental levels 10%, 15% and 20% the properties of milk powder were studied such as color, moisture content, percentage yield (%yield) and solubility index. The experiment revealed that prebiotic carriers could replace maltodextrin and improve quality, such as solubility and percentage yield, and enriched nutrients, such as dietary fiber. CB, RMD, and PDX are three possible carriers, which are applied to both regular cow's milk formula and lactose-free cow milk.

Keywords: lactose-free milk powder, prebiotic carrier, co-particle, glycemic index

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3431 Development and Structural Characterization of a Snack Food with Added Type 4 Extruded Resistant Starch

Authors: Alberto A. Escobar Puentes, G. Adriana García, Luis F. Cuevas G., Alejandro P. Zepeda, Fernando B. Martínez, Susana A. Rincón

Abstract:

Snack foods are usually classified as ‘junk food’ because have little nutritional value. However, due to the increase on the demand and third generation (3G) snacks market, low price and easy to prepare, can be considered as carriers of compounds with certain nutritional value. Resistant starch (RS) is classified as a prebiotic fiber it helps to control metabolic problems and has anti-cancer colon properties. The active compound can be developed by chemical cross-linking of starch with phosphate salts to obtain a type 4 resistant starch (RS4). The chemical reaction can be achieved by extrusion, a process widely used to produce snack foods, since it's versatile and a low-cost procedure. Starch is the major ingredient for snacks 3G manufacture, and the seeds of sorghum contain high levels of starch (70%), the most drought-tolerant gluten-free cereal. Due to this, the aim of this research was to develop a snack (3G), with RS4 in optimal conditions extrusion (previously determined) from sorghum starch, and carry on a sensory, chemically and structural characterization. A sample (200 g) of sorghum starch was conditioned with 4% sodium trimetaphosphate/ sodium tripolyphosphate (99:1) and set to 28.5% of moisture content. Then, the sample was processed in a single screw extruder equipped with rectangular die. The inlet, transport and output temperatures were 60°C, 134°C and 70°C, respectively. The resulting pellets were expanded in a microwave oven. The expansion index (EI), penetration force (PF) and sensory analysis were evaluated in the expanded pellets. The pellets were milled to obtain flour and RS content, degree of substitution (DS), and percentage of phosphorus (% P) were measured. Spectroscopy [Fourier Transform Infrared (FTIR)], X-ray diffraction, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) analysis were performed in order to determine structural changes after the process. The results in 3G were as follows: RS, 17.14 ± 0.29%; EI, 5.66 ± 0.35 and PF, 5.73 ± 0.15 (N). Groups of phosphate were identified in the starch molecule by FTIR: DS, 0.024 ± 0.003 and %P, 0.35±0.15 [values permitted as food additives (<4 %P)]. In this work an increase of the gelatinization temperature after the crosslinking of starch was detected; the loss of granular and vapor bubbles after expansion were observed by SEM; By using X-ray diffraction, loss of crystallinity was observed after extrusion process. Finally, a snack (3G) was obtained with RS4 developed by extrusion technology. The sorghum starch was efficient for snack 3G production.

Keywords: extrusion, resistant starch, snack (3G), Sorghum

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3430 Advantages of Sexual Reproduction in Aspergillus nidulans

Authors: Adel Omar Ashour, Paul S. Dyer

Abstract:

Aspergillus nidulans can reproduce by asexual or sexual means, producing green conidiospores or red-purple ascospores respectively. The latter one is produced in dark-purple globose ‘cleistothecia’ which are surrounded by Hülle cells. The species has a homothallic (self fertile) sexual breeding system. Given the extra metabolic costs associated with sexual compared to asexual reproduction it would be predicted that ascospore production would confer evolutionary benefits. However, due to the homothallic breeding system there is very rarely any increased genetic variation in ascospore offspring and traditionally conidia and ascospores are considered to be equally environmental resistant. We therefore examined in detail whether conidia and ascospores might exhibit as yet undetected differences in spore viability when subjected to certain environmental stressors. Spores from two strains of A. nidulans (comprising wild-type and KU mutants) were exposed to various levels of temperature (50-70°C for 30 min) and UV (350 nm for 10-60 min) stress. Results of experiments will be presented, including comparison of ‘D’ (decimal point reduction) values of conidia versus ascospores of A. nidulans. We detected that under certain exposure levels ascospores have significantly increased resistance compared to conidia. The increased environmental resistance of ascospores might be a key factor explaining the persistence of sexuality in this homothallic species, and reasons for differential survival are suggested.

Keywords: Aspergillus nidulans, asexual reproduction, conidia, ascospores, cleistothecia, d-value

Procedia PDF Downloads 359
3429 Screening Deformed Red Blood Cells Irradiated by Ionizing Radiations Using Windowed Fourier Transform

Authors: Dahi Ghareab Abdelsalam Ibrahim, R. H. Bakr

Abstract:

Ionizing radiation, such as gamma radiation and X-rays, has many applications in medical diagnoses and cancer treatment. In this paper, we used the windowed Fourier transform to extract the complex image of the deformed red blood cells. The real values of the complex image are used to extract the best fitting of the deformed cell boundary. Male albino rats are irradiated by γ-rays from ⁶⁰Co. The male albino rats are anesthetized with ether, and then blood samples are collected from the eye vein by heparinized capillary tubes for studying the radiation-damaging effect in-vivo by the proposed windowed Fourier transform. The peripheral blood films are prepared according to the Brown method. The peripheral blood film is photographed by using an Automatic Image Contour Analysis system (SAMICA) from ELBEK-Bildanalyse GmbH, Siegen, Germany. The SAMICA system is provided with an electronic camera connected to a computer through a built-in interface card, and the image can be magnified up to 1200 times and displayed by the computer. The images of the peripheral blood films are then analyzed by the windowed Fourier transform method to extract the precise deformation from the best fitting. Based on accurate deformation evaluation of the red blood cells, diseases can be diagnosed in their primary stages.

Keywords: windowed Fourier transform, red blood cells, phase wrapping, Image processing

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3428 The Influence of Amygdalin on Glioblastoma Multiforme Cell Lines

Authors: Sylwia K. Naliwajko, Justyna Moskwa, Patryk Nowakowski, Renata Markiewicz-Zukowska, Krystyna Gromkowska-Kepka, Anna Puscion-Jakubik, Maria H. Borawska

Abstract:

Amygdalin is found in many fruit seeds, including apricot, peach, quince, apples, and almonds. Amygdalin (also named vitamin B17), as well as its sources, are commonly used as an alternative therapy or prevention of cancer. The potential activity of amygdalin is related to its enzymatic degradation to the hydrogen cyanide. Hydrogen cyanide is a toxic substance that causes liver and nerves damage, fever, coma or even death. Amygdalin is much better tolerated after intravenous than oral administration. The aim of this study was to examine the influence of amygdalin on glioblastoma multiforme cell lines. Three glioblastoma multiforme cell lines – U87MG, T98, LN18 were incubated (48 h) with amygdalin in concentrations 100, 250, 500, 1000 and 2000 µg/mL. The MTT (Thiazolyl Blue Tetrazolium Bromide) test and DNA binding test by [3H]-thymidine incorporation were used to determine the anti-proliferative activity of amygdalin. The secretion of metalloproteinases (MMP2 and MMP-9) from U87MG cells was estimated by gelatin zymography. The statistical analysis was performed using Statistica v. 13.0 software. The data was presented as a % of control. Amygdalin did not show significant inhibition of viability of all the glioblastoma cells in concentrations 100, 250, 500, 1000 µg/mL. In 2000 µg/mL there were significant differences compared to the control, but inhibition of viability was less than 20% (more than 80% of control). The average viability of U87MG cells was 92,0±4%, T98G: 85,8±3% and LN18: 94,7±2% of the control. There was no dose-response viability, and IC50 value was not recognized. DNA binding in U87MG cells was not inhibited (109,0±3 % of control). After treatment with amygdalin, we observed significantly increased secretion of MMP2 and MMP9 in U87MG cells (130,3±14% and 112,0±5% of control, respectively). Our results suggest that amygdalin has no anticancer activity in glioblastoma cell lines.

Keywords: amygdalin, anticancer, cell line, glioblastoma

Procedia PDF Downloads 216
3427 Targeting Basic Leucine Zipper Transcription Factor ATF-Like Mediated Immune Cells Regulation to Reduce Crohn’s Disease Fistula Incidence

Authors: Mohammadjavad Sotoudeheian, Soroush Nematollahi

Abstract:

Crohn’s disease (CD) is a chronic gastrointestinal segment inflammation encompassing immune dysregulation in a genetically susceptible individual in response to the environmental triggers and interaction between the microbiome and immune system. Uncontrolled inflammation leads to long-term complications, including fibrotic strictures and enteric fistulae. Increased production of Th1 and Th17-cell cytokines and defects in T-regulatory cells have been associated with CD. Th17-cells are essential for protection against extracellular pathogens, but their atypical activity can cause autoimmunity. Intrinsic defects in the control of programmed cell death in the mucosal T-cell compartment are strongly implicated in the pathogenesis of CD. The apoptosis defect in mucosal T-cells in CD has been endorsed as an imbalance of the Bcl-2 and the Bax. The immune system encounters foreign antigens through microbial colonization of mucosal surfaces or infections. In addition, FOSL downregulated IL-26 expression, a cytokine that marks inflammatory Th17-populations in patients suffering from CD. Furthermore, the expression of IL-23 is associated with the transcription factor primary leucine zipper transcription factor ATF-like (Batf). Batf-deficiency demonstrated the crucial role of Batf in colitis development. Batf and IL-23 mediate their effects by inducing IL-6 production. Strong association of IL-23R, Stat3, and Stat4 with IBD susceptibility point to a critical involvement of T-cells. IL-23R levels in transfer fistula were dependent on the AP-1 transcription factor JunB that additionally controlled levels of RORγt by facilitating DNA binding of Batf. T lymphocytes lacking JunB failed to induce IL-23- and Th17-mediated experimental colitis highlighting the relevance of JunB for the IL-23/ Th17 pathway. The absence of T-bet causes unrestrained Th17-cell differentiation. T-cells are central parts of immune-mediated colon fistula. Especially Th17-cells were highly prevalent in inflamed IBD tissues, as RORγt is effective in preventing colitis. Intraepithelial lymphocytes (IEL) contain unique T-cell subsets, including cells expressing RORγt. Increased activated Th17 and decreased T-regulatory cells in inflamed intestinal tissues had been seen. T-cells differentiate in response to many cytokines, including IL-1β, IL-6, IL-23, and TGF-β, into Th17-cells, a process which is critically dependent on the Batf. IL-23 promotes Th17-cell in the colon. Batf manages the generation of IL-23 induced IL-23R+ Th17-cells. Batf is necessary for TGF-β/IL-6-induced Th17-polarization. Batf-expressing T-cells are the core of T-cell-mediated colitis. The human-specific parts of three AP-1 transcription factors, FOSL1, FOSL2, and BATF, are essential during the early stages of Th17 differentiation. BATF supports the Th17 lineage. FOSL1, FOSL2, and BATF make possession of regulatory loci of genes in the Th17 lineage cascade. The AP1 transcription factor Batf is identified to control intestinal inflammation and seems to regulate pathways within lymphocytes, which could theoretically control the expression of several genes. It shows central regulatory properties over Th17-cell development and is intensely upregulated within IBD-affected tissues. Here, we demonstrated that targeting Batf in IBD appears as a therapeutic approach that reduces colitogenic T-cell activities during fistula formation while aiming to affect inflammation in the gut epithelial cells.

Keywords: immune system, Crohn’s Disease, BATF, T helper cells, Bcl, interleukin, FOSL

Procedia PDF Downloads 145
3426 Antibacterial Activity of Rosmarinus officinalis (Rosemary) and Murraya koenigii (Curry Leaves) against Multidrug Resistant S. aureus and Coagulase Negative Staphylococcus Species

Authors: Asma Naim, Warda Mushtaq

Abstract:

Staphylococcus species are the most versatile and adaptive organism. They are widespread and naturally found on the skin, mucosa and nose in humans. Among these, Staphylococcus aureus is the most important species. These organisms act as opportunistic pathogens and can infect various organs of the host, causing minor skin infection to severe toxin mediated diseases, and life threatening nosocomial infections. Staphylococcus aureus has acquired resistance against β-lactam antibiotics by the production of β-lactamase, and Methicillin-Resistant Staphylococcus aureus (MRSA) strains have also been reported with increasing frequency. MRSA strains have been associated with nosocomial as well as community acquired infections. Medicinal plants have enormous potential as antimicrobial substances and have been used in traditional medicine. Search for medicinally valuable plants with antimicrobial activity is being emphasized due to increasing antibiotic resistance in bacteria. In the present study, the antibacterial potential of Rosmarinus officinalis (Rosemary) and Murraya koenigii (curry leaves) was evaluated. These are common household herbs used in food as enhancer of flavor and aroma. The crude aqueous infusion, decoction and ethanolic extracts of curry leaves and rosemary and essential oil of rosemary were investigated in the present study for antibacterial activity against multi-drug resistant Staphylococcus strains using well diffusion method. In the present study, 60 Multi-drug resistant clinical isolates of S. aureus (43) and Coagulase Negative Staphylococci (CoNS) (17) were screened against different concentrations of crude extracts of Rosmarinus officinalis and Murraya koenigii. Out of these 60 isolates, 43 were sensitive to the aqueous infusion of rosemary; 23 to aqueous decoction and 58 to ethanolic extract whereas, 24 isolates were sensitive to the essential oil. In the case of the curry leaves, no antibacterial activity was observed in aqueous infusion and decoction while only 14 isolates were sensitive to the ethanolic extract. The aqueous infusion of rosemary (50% concentration) exhibited a zone of inhibition of 21(±5.69) mm. against CoNS and 17(±4.77) mm. against S. aureus, the zone of inhibition of 50% concentration of aqueous decoction of rosemary was also larger against CoNS 17(±5.78) mm. then S. aureus 13(±6.91) mm. and the 50% concentrated ethanolic extract showed almost similar zone of inhibition in S. aureus 22(±3.61) mm. and CoNS 21(±7.64) mm. whereas, the essential oil of rosemary showed greater zone of inhibition against S. aureus i.e., 16(±4.67) mm. while CoNS showed 15(±6.94) mm. These results show that ethanolic extract of rosemary has significant antibacterial activity. Aqueous infusion and decoction of curry leaves revealed no significant antibacterial potential against all Staphylococcal species and ethanolic extract also showed only a weak response. Staphylococcus strains were susceptible to crude extracts and essential oil of rosemary in a dose depend manner, where the aqueous infusion showed highest zone of inhibition and ethanolic extract also demonstrated antistaphylococcal activity. These results demonstrate that rosemary possesses antistaphylococcal activity.

Keywords: antibacterial activity, curry leaves, multidrug resistant, rosemary, S. aureus

Procedia PDF Downloads 248
3425 Positive Effects of Aerobic Exercise after Bone Marrow Stem Cell Transplantation on Recovery of Dopaminergic Neurons and Promotion of Angiogenesis Markers in the Striatum of Parkinsonian Rats

Authors: S. A. Hashemvarzi, A. Heidarianpour, Z. Fallahmohammadi, M. Pourghasem, M. Kaviani

Abstract:

Introduction: Parkinson’s disease (PD) is a progressive neurodegenerative in the central nervous system characterized by the loss of dopaminergic neurons in the substantia nigra resulting in loss of dopamine release in the striatum. Non-drug treatment options such as Stem cell transplantation and exercise have been considered for treatment of Parkinson's disease. Purpose: The purpose of this study was to evaluate the effect of aerobic exercise after bone marrow stem cells transplantation on recovery of dopaminergic neurons and promotion of angiogenesis markers in the striatum of parkinsonian rats. Materials and Methods: 42 male Wistar rats were divided randomly into six groups: Normal (N), Sham (S), Parkinson’s (P), Stem cells transplanted Parkinson’s (SP), Exercised Parkinson’s (EP) and Stem cells transplanted + Exercised Parkinson’s (SEP). To create a model of Parkinson's, the striatum was destroyed by injection of 6-hydroxy-dopamine into the striatum through stereotaxic apparatus. Stem cells were derived from the bone marrow of femur and tibia of male rats with 6-8 weeks old. After cultivation, approximately 5×105 cells in 5 microliter of medium were injected into the striatum of rats through the channel. Aerobic exercise was included 8 weeks of running on the treadmill with a speed of 15 meters per minute. At the end, all subjects were decapitated and striatum tissues were separately isolated for measurement of vascular endothelial growth factor (VEGF), dopamine (DA) and tyrosine hydroxylase (TH) levels. Results: VEGF, DA and TH levels in the striatum of parkinsonian rats significantly increased in treatment groups (SP, EP and SEP), especially in SEP group compared to P group after treatment (P<0.05). Conclusion: The findings implicate that the BMSCs transplantation in combination with exercise would have synergistic effects leading to functional recovery, dopaminergic neurons recovery and promotion of angiogenesis marker in the striatum of parkinsonian rats.

Keywords: stem cells, treadmill training, neurotrophic factors, Parkinson

Procedia PDF Downloads 342
3424 Microbial Fuel Cells and Their Applications in Electricity Generating and Wastewater Treatment

Authors: Shima Fasahat

Abstract:

This research is an experimental research which was done about microbial fuel cells in order to study them for electricity generating and wastewater treatment. These days, it is very important to find new, clean and sustainable ways for energy supplying. Because of this reason there are many researchers around the world who are studying about new and sustainable energies. There are different ways to produce these kind of energies like: solar cells, wind turbines, geothermal energy, fuel cells and many other ways. Fuel cells have different types one of these types is microbial fuel cell. In this research, an MFC was built in order to study how it can be used for electricity generating and wastewater treatment. The microbial fuel cell which was used in this research is a reactor that has two tanks with a catalyst solution. The chemical reaction in microbial fuel cells is a redox reaction. The microbial fuel cell in this research is a two chamber MFC. Anode chamber is an anaerobic one (ABR reactor) and the other chamber is a cathode chamber. Anode chamber consists of stabilized sludge which is the source of microorganisms that do redox reaction. The main microorganisms here are: Propionibacterium and Clostridium. The electrodes of anode chamber are graphite pages. Cathode chamber consists of graphite page electrodes and catalysts like: O2, KMnO4 and C6N6FeK4. The membrane which separates the chambers is Nafion117. The reason of choosing this membrane is explained in the complete paper. The main goal of this research is to generate electricity and treating wastewater. It was found that when you use electron receptor compounds like: O2, MnO4, C6N6FeK4 the velocity of electron receiving speeds up and in a less time more current will be achieved. It was found that the best compounds for this purpose are compounds which have iron in their chemical formula. It is also important to pay attention to the amount of nutrients which enters to bacteria chamber. By adding extra nutrients in some cases the result will be reverse.  By using ABR the amount of chemical oxidation demand reduces per day till it arrives to a stable amount.

Keywords: anaerobic baffled reactor, bioenergy, electrode, energy efficient, microbial fuel cell, renewable chemicals, sustainable

Procedia PDF Downloads 227
3423 Research on the Effect of Accelerated Aging Illumination Mode on Bifacial Solar Modules

Authors: T. H. Huang, C. L. Fern, Y. K. Tseng

Abstract:

The design and reliability of solar photovoltaic modules are crucial to the development of solar energy, and efforts are still being made to extend the life of photovoltaic modules to improve their efficiency because natural aging is time-consuming and does not provide manufacturers and investors with timely information, accelerated aging is currently the best way to estimate the life of photovoltaic modules. Bifacial solar cells not only absorb light from the front side but also absorb light reflected from the ground on the back side, surpassing the performance of single-sided solar cells. Due to the asymmetry of the two sides of the light, in addition to the difference in photovoltaic conversion efficiency, there will also be differences in heat distribution, which will affect the electrical properties and material structure of the bifacial solar cell itself. In this study, there are two types of experimental samples: packaged and unpackaged and then irradiated with UVC light sources and halogen lamps for accelerated aging, as well as a control group without aging. After two weeks of accelerated aging, the bifacial solar cells were visual observation, and infrared thermal images were taken; then, the samples were subjected to IV measurement, and samples were taken for SEM, Raman, and XRD analyses in order to identify the defects that lead to failure and chemical changes, as well as to analyze the reasons for the degradation of their characteristics. From the results of the analysis, it is found that aging will cause carbonization of the polymer material on the surface of bifacial solar cells, and the crystal structure will be affected.

Keywords: bifacial solar cell, accelerated aging, temperature, characterization, electrical measurement

Procedia PDF Downloads 111
3422 Using Electro-Biogrouting to Stabilize of Soft Soil

Authors: Hamed A. Keykha, Hadi Miri

Abstract:

This paper describes a new method of soil stabilisation, electro-biogrouting (EBM), for improvement of soft soil with low hydraulic conductivity. This method uses an applied voltage gradient across the soil to induce the ions and bacteria cells through the soil matrix, resulting in CaCO3 precipitation and an increase of the soil shear strength in the process. The EBM were used effectively with two injection methods; bacteria injection and products of bacteria injection. The bacteria cells, calcium ions and urea were moved across the soil by electromigration and electro osmotic flow respectively. The products of bacteria (CO3-2) were moved by electromigration. The results showed that the undrained shear strength of the soil increased from 6 to 65 and 70 kPa for first and second injection method respectively. The injection of carbonate solution and calcium could be effectively flowed in the clay soil compare to injection of bacteria cells. The detection of CaCO3 percentage and its corresponding water content across the specimen showed that the increase of undrained shear strength relates to the deposit of calcite crystals between soil particles.

Keywords: Sporosarcina pasteurii, electrophoresis, electromigration, electroosmosis, biocement

Procedia PDF Downloads 528