Search results for: natural killer cells
7957 Developing a Thermo-Sensitive Conductive Stretchable Film to Allow Cell Sheet Harvest after Mechanical and Electrical Treatments
Authors: Wei-Wen Hu, Yong-Zhi Zhong
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Depositing conductive polypyrrole (PPy) onto elastic polydimethylsiloxane (PDMS) substrate can obtain a highly stretchable conductive film, which can be used to construct a bioreactor to cyclically stretch and electrically stimulate surface cells. However, how to completely harvest these stimulated muscle tissue to repair damaged muscle is a challenge. To address this concern, N-isopropylacrylamide (NIPAAm), a monomer of temperature-sensitive polymer, was added during the polymerization of pyrrole on PDMS so that the resulting P(Py-co-NIPAAm)/PDMS should own both conductivity and thermo-sensitivity. Therefore, cells after stimulation can be completely harvested as cell sheets by reducing temperature. Mouse skeletal myoblast, C2C12 cells, were applied to examine our hypothesis. In electrical stimulation, C2C12 cells on P(Py-co-NIPAAm)/PDMS demonstrated the best myo-differentiation under the electric field of 1 V/cm. Regarding cyclic stretching, the strain equal to or higher than 9% can highly align C2C12 perpendicular to the stretching direction. The Western blotting experiments demonstrated that the cell sheets harvested by cooling reserved more extracellular matrix (ECM) than cells collected by the traditional trypsin digestion method. Immunostaining of myosin heavy chain protein (MHC) indicated that both mechanical and electrical stimuli effectively increased the number of myotubes and the differentiation ratio, and the myotubes can be aligned by cyclic stretching. Stimulated cell sheets can be harvested by cooling, and the alignment of myotubes was still maintained. These results suggested that the deposition of P(Py-co-NIPAAm) on PDMS can be applied to harvest intact cell sheets after cyclic stretching and electrical stimulation, which increased the feasibility of bioreactor for the application of tissue engineering and regenerative medicine.Keywords: bioreactor, cell sheet, conductive polymer, cyclic stretching, electrical stimulation, muscle tissue engineering, myogenesis, thermosensitive hydrophobicity
Procedia PDF Downloads 967956 Quantitative Analysis of Orphan Nuclear Receptors in Insulin Resistant C2C12 Skeletal Muscle Cells
Authors: Masocorro Gawned, Stephen Myers, Guat Siew Chew
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Nuclear Receptors (NR) are a super family of transcription factors that play a major role in lipid and glucose metabolism in skeletal muscle. Recently, pharmacological evidence supports the view that stimulation of nuclear receptors alleviates Type 2 Diabetes (T2D). The orphan nuclear receptors (ONR) are members of the nuclear receptor (NR) superfamily whose ligands and physiological functions remain unknown. To date, no systematic studies have been carried out to screen for ONRs expressed in insulin resistant (IR) skeletal muscle cells. Therefore, in this study, we have established a model for IR by treating C2C12 skeletal muscle cells with insulin (10nM) for 48 hours. Western Blot analysis of phosphorylated AKT confirmed IR. Real-time quantitative polymerase chain reaction (qPCR) results highlighted key ONRs including NUR77 (NR4A1), NURR1 (NR4A2) and NOR1 (NR4A3) which have been associated with fatty acid oxidation regulation and glucose homeostasis. Increased mRNA expression levels of estrogen-related receptors (ERRs), REV-ERBα, NUR77, NURR1, NOR1, in insulin resistant C2C12 skeletal muscle cells, indicated that these ONRs could potentially play a pivotal regulatory role of insulin secretion in lipid metabolism. Taken together, this study has successfully contributed to the complete analysis of ONR in IR, and has filled in an important void in the study and treatment of T2D.Keywords: type 2 diabetes, orphan nuclear receptors, transcription receptors, quantitative mRNA expression
Procedia PDF Downloads 4277955 Electric Power Generation by Thermoelectric Cells and Parabolic Solar Concentrators
Authors: A. Kianifar, M. Afzali, I. Pishbin
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In this paper, design details, theoretical analysis and thermal performance analysis of a solar energy concentrator suited to combined heat and thermoelectric power generation are presented. The thermoelectric device is attached to the absorber plate to convert concentrated solar energy directly into electric energy at the focus of the concentrator. A cooling channel (water cooled heat sink) is fitted to the cold side of the thermoelectric device to remove the waste heat and maintain a high temperature gradient across the device to improve conversion efficiency.Keywords: concentrator thermoelectric generator, CTEG, solar energy, thermoelectric cells
Procedia PDF Downloads 3057954 The Role of Estradiol-17β and Type IV Collagen on the Regulation and Expression Level Of C-Erbb2 RNA and Protein in SKOV-3 Ovarian Cancer Cell Line
Authors: Merry Meryam Martgrita, Marselina Irasonia Tan
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One of several aggresive cancer is cancer that overexpress c-erbB2 receptor along with the expression of estrogen receptor. Components of extracellular matrix play an important role to increase cancer cells proliferation, migration and invasion. Both components can affect cancer development by regulating the signal transduction pathways in cancer cells. In recent research, SKOV-3 ovarian cancer cell line, that overexpress c-erbB2 receptor was cultured on type IV collagen and treated with estradiol-17β, to reveal the role of both components on RNA and protein level of c-erbB2 receptor. In this research we found a modulation phenomena of increasing and decreasing of c-erbB2 RNA level and a stabilisation phenomena of c-erbB2 protein expression due to estradiol-17β and type IV collagen. It seemed that estradiol-17β has an important role to increase c-erbB2 transcription and the stability of c-erbB2 protein expression. Type IV collagen has an opposite role. It blocked c-erbB2 transcription when it bound to integrin receptor in SKOV-3 cells.Keywords: c-erbB2, estradiol-17β, SKOV-3, type IV collagen
Procedia PDF Downloads 2847953 Cytoxicity Studies of Sachets Beverages Using Allium Cepa Test
Authors: Ja’Afar Umar, Naziru Salisu
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The consumption of powdered or industrialized juices has increased globally due to the fast pace of city life. These foods, with their attractive color, odor, and taste, are easily diluted in water and can lead to obesity, diabetes, hypertension, and cardiovascular problems. In a study, 80 purple varieties of onion bulbs were used to evaluate the cytotoxicity of the Tiara and Bevi mix beverage powder. The viability of the bulbs was tested using the A. cepa toxicity test. The bulbs were divided into five groups, and the root growth was recorded. The mixture was then squashed in a 45% acetic acid solution and examined for chromosomal abnormalities. The chromosomal abnormalities were classified as bridges, c-mitoses, vagrants, fragments, stickiness, bi-nuclei, and multi-polar. The study found that the highest number of dividing cells was in the negative control group, followed by the group treated with BM beverage. The highest number of aberrant cells was in the group treated with TR beverage, followed by BM 5%. Stickiness of cells was observed in both BM and TR 5% beverage concentrations. No lagging chromosome was present in the negative control group. The highest mitotic index was in the negative control group, and bridge fragrance was observed in the groups treated with different beverages. This study highlights the importance of Allium cepa L. in genotoxic substance testing, revealing chromosomal and mitotic abnormalities in root tip cells. The study also reveals that at 5% concentrations, root growth decreases, indicating potential genetic abnormalities in Allium cepa's genetic material.Keywords: cytotoxicity, Allium cepa, Beverages, Chromosome
Procedia PDF Downloads 177952 In vitro Cytotoxic and Genotoxic Effects of Arsenic Trioxide on Human Keratinocytes
Authors: H. Bouaziz, M. Sefi, J. de Lapuente, M. Borras, N. Zeghal
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Although arsenic trioxide has been the subject of toxicological research, in vitro cytotoxicity and genotoxicity studies using relevant cell models and uniform methodology are not well elucidated. Hence, the aim of the present study was to evaluate the cytotoxicity and genotoxicity induced by arsenic trioxide in human keratinocytes (HaCaT) using the MTT [3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and alkaline single cell gel electrophoresis (Comet) assays, respectively. Human keratinocytes were treated with different doses of arsenic trioxide for 4 h prior to cytogenetic assessment. Data obtained from the MTT assay indicated that arsenic trioxide significantly reduced the viability of HaCaT cells in a dose-dependent manner, showing a IC50 value of 34.18 ± 0.6 µM. Data generated from the comet assay also indicated a significant dose-dependent increase in DNA damage in HaCaT cells associated with arsenic trioxide exposure. We observed a significant increase in comet tail length and tail moment, showing an evidence of arsenic trioxide -induced genotoxic damage in HaCaT cells. This study confirms that the comet assay is a sensitive and effective method to detect DNA damage caused by arsenic.Keywords: arsenic trioxide, cytotoxixity, genotoxicity, HaCaT
Procedia PDF Downloads 2577951 Catalytic Study of Natural Gas Based Solid Oxide Fuel Cell
Authors: Nasir Iqbal, Khurram Siraj, Rizwan Raza
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Solid oxide fuel cell (SOFC) is the promising technology now days. SOFC can be operated with different types of fuels available. In this work catalytic anode is prepared with metal oxides i.e. Li, Ni, Zn and Sn and tested for catalytic activity with natural gas as a fuel. The operating temperature range is 170-750°C as observed with the help of TGA. Electrical conductivity and fuel cell performance has been observed for four different samples with varying composition of Sn and Zn. It is concluded that the sample having greater concentration of Zn shows better conductivity and power density results. All the results are promising and verified with different characterizations.Keywords: catalytic activity, solid oxide fuel cell, energy material, natural gas
Procedia PDF Downloads 797950 Caffeic Acid Methyl and Ethyl Esters Exhibit Beneficial Effect on Glucose and Lipid Metabolism in Cultured Murine Insulin-Sensitive Cells
Authors: Hoda M. Eid, Abir Nachar, Farah Thong, Gary Sweeney, Pierre S. Haddad
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Caffeic acid methyl ester (CAME) and caffeic ethyl esters (CAEE) were previously reported to potently stimulate glucose uptake in cultured C2C12 skeletal muscle cells via insulin-independent mechanisms involving the activation of adenosine monophosphate-activated protein kinase (AMPK). In the present study, we investigated the effect of the two compounds on the translocation of glucose transporter GLUT4 in L6 skeletal muscle cells. The cells were treated with the optimum non-toxic concentration (50 µM) of either CAME or CAEE for 18 h. Levels of GLUT4myc at the cell surface were measured by O-phenylenediamine dihydrochloride (OPD) assay. The effects of CAME and CAEE on GLUT1 and GLUT4 protein content were also measured by western immunoblot. Our results show that CAME and CAEE significantly increased glucose uptake, GLUT4 translocation and GLUT4 protein content. Furthermore, the effect of the two CA esters on two insulin-sensitive cell lines: H4IIE rat hepatoma and 3T3-L1 adipocytes were investigated. CAME and CAEE reduced the enzymatic activity of the key hepatic gluconeogenic enzyme glucose-6-phosphatase in a concentration-dependent manner. In addition, they exerted a concentration-dependent antiadipogenic effect on 3T3-L1 cells. Mitotic clonal expansion (MCE), a prerequisite for adipocytes differentiation was also concentration-dependently inhibited. The two compounds abrogated lipid droplet accumulation, blocked MCE and maintained cells in fibroblast-like state when applied at the maximum non-toxic concentration (100 µM). In addition, the expression of the early key adipogenic transcription factors CCAAT enhancer-binding protein beta (C/EBP-β) and the master regulator of adipogenesis peroxisome-proliferator-activated receptor gamma (PPAR-γ) were inhibited. We, therefore, conclude that CAME and CAEE exert pleiotropic benefits in several insulin-sensitive cell lines through insulin-independent mechanisms involving AMPK, hence they may treat obesity, diabetes and other metabolic diseases.Keywords: type 2 diabetes mellitus, insulin resistance, GLUT4, Akt, AMPK.
Procedia PDF Downloads 3097949 The Effect of Some Macrofungi Extracts on Cytoplasmic Membrane of Multidrug Resistant Bacteria by Flow Cytometry
Authors: Yener Tekeli, Hayri Baba
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The natural active compounds found in medicinal plants are belong to various chemical structures including polyphenolic compounds, flavonoids, essential oils, and vitamins and some of these compounds have anticancer, antioxidant, and antimicrobial activity. However, these compounds have been little known about mechanisms to confer antibacterial drug resistance. In this study; some macrofungi extracts (Pholiota lucifera, Gnaoderma applanatum and Pleurotus ostreatus) were investigated for their abilities to enhance bacterial permeability by flow cytometry. This experiments exhibited enhancement of these extracts to disrupt the cytoplasmic membrane of living bacterial (Listeria innocua and Escherichia coli) cells. These experiments were designed to detect uptake of PI&SYT by enhancing with a ranged concentration of herb extracts.Keywords: antimicrobial activity, flow cytometry, macrofungi, multidrug resistant
Procedia PDF Downloads 4457948 SPR Immunosensor for the Detection of Staphylococcus aureus
Authors: Muhammad Ali Syed, Arshad Saleem Bhatti, Chen-zhong Li, Habib Ali Bokhari
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Surface plasmon resonance (SPR) biosensors have emerged as a promising technique for bioanalysis as well as microbial detection and identification. Real time, sensitive, cost effective, and label free detection of biomolecules from complex samples is required for early and accurate diagnosis of infectious diseases. Like many other types of optical techniques, SPR biosensors may also be successfully utilized for microbial detection for accurate, point of care, and rapid results. In the present study, we have utilized a commercially available automated SPR biosensor of BI company to study the microbial detection form water samples spiked with different concentration of Staphylococcus aureus bacterial cells. The gold thin film sensor surface was functionalized to react with proteins such as protein G, which was used for directed immobilization of monoclonal antibodies against Staphylococcus aureus. The results of our work reveal that this immunosensor can be used to detect very small number of bacterial cells with higher sensitivity and specificity. In our case 10^3 cells/ml of water have been successfully detected. Therefore, it may be concluded that this technique has a strong potential to be used in microbial detection and identification.Keywords: surface plasmon resonance (SPR), Staphylococcus aureus, biosensors, microbial detection
Procedia PDF Downloads 4767947 Application of Thermoplastic Microbioreactor to the Single Cell Study of Budding Yeast to Decipher the Effect of 5-Hydroxymethylfurfural on Growth
Authors: Elif Gencturk, Ekin Yurdakul, Ahmet Y. Celik, Senol Mutlu, Kutlu O. Ulgen
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Yeast cells are generally used as a model system of eukaryotes due to their complex genetic structure, rapid growth ability in optimum conditions, easy replication and well-defined genetic system properties. Thus, yeast cells increased the knowledge of the principal pathways in humans. During fermentation, carbohydrates (hexoses and pentoses) degrade into some toxic by-products such as 5-hydroxymethylfurfural (5-HMF or HMF) and furfural. HMF influences the ethanol yield, and ethanol productivity; it interferes with microbial growth and is considered as a potent inhibitor of bioethanol production. In this study, yeast single cell behavior under HMF application was monitored by using a continuous flow single phase microfluidic platform. Microfluidic device in operation is fabricated by hot embossing and thermo-compression techniques from cyclo-olefin polymer (COP). COP is biocompatible, transparent and rigid material and it is suitable for observing fluorescence of cells considering its low auto-fluorescence characteristic. The response of yeast cells was recorded through Red Fluorescent Protein (RFP) tagged Nop56 gene product, which is an essential evolutionary-conserved nucleolar protein, and also a member of the box C/D snoRNP complexes. With the application of HMF, yeast cell proliferation continued but HMF slowed down the cell growth, and after HMF treatment the cell proliferation stopped. By the addition of fresh nutrient medium, the yeast cells recovered after 6 hours of HMF exposure. Thus, HMF application suppresses normal functioning of cell cycle but it does not cause cells to die. The monitoring of Nop56 expression phases of the individual cells shed light on the protein and ribosome synthesis cycles along with their link to growth. Further computational study revealed that the mechanisms underlying the inhibitory or inductive effects of HMF on growth are enriched in functional categories of protein degradation, protein processing, DNA repair and multidrug resistance. The present microfluidic device can successfully be used for studying the effects of inhibitory agents on growth by single cell tracking, thus capturing cell to cell variations. By metabolic engineering techniques, engineered strains can be developed, and the metabolic network of the microorganism can thus be manipulated such that chemical overproduction of target metabolite is achieved along with the maximum growth/biomass yield.Keywords: COP, HMF, ribosome biogenesis, thermoplastic microbioreactor, yeast
Procedia PDF Downloads 1717946 Chemical and Bioactive Constituents Isolated from the Formosa Zamia furfureace L.
Authors: Chien-Liang Chao, Yun-Sheng Lin
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Secondary metabolites are applied in the human life of the Chinese herbal medicine. Many drugs are originally extracted from natural products with combination of pharmaceutical and chemical studies. Crude extract of the leaves from Zamia furfureace L. has been shown to exhibit anticancer activities. The first chemical investigation of this plant was carried out by our group. In this study, four known compounds were isolated from Zamia furfureace L. with three lignins (Sesamin (1), Wodeshiol (2) and Paulownin (3)), and one dipeptide (Aurantiamide acetate (4)). The structures of these compounds were analyzed through the 1D-NMR(1H-NMR,13C-NMR)、2D-NMR(COSY、HMQC、HMBC、NOESY) spectroscopic analysis, and by comparison of variety of physical data (IR, mass spectrometry, ultraviolet, optical rotation). Among them, Aurantiamide acetate (4) exhibited weak cytotoxic activity against human gastric cancer cells.Keywords: Zamia furfureace L., AGS, sesamin, Aurantiamide acetate, secondary metabolites
Procedia PDF Downloads 4897945 Characterization of a Mesenchymal Stem Cells Pool in Killian Nasal Polyp
Authors: Emanuela Chiarella, Clelia Nisticò, Nicola Lombardo, Giovanna Lucia Piazzetta, Nadia Lobello, Maria Mesuraca
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Killian’s Antrochoanal Polyp is a benign lesion of the maxillary sinus characterized by unilateral nasal obstruction, pus discharge, and headache. It affects, more commonly children and young adults. Although its etiology still remains unclear, chronic inflammation, autoreactivity, allergies, and viral infections are strongly associated with its formation and development, resulting in nasal tissue remodeling. We aimed to investigate the stem cells components which reside in this pathological tissue. In particular, we adopted a protocol for the isolation and culturing of mesenchymal stem cells from surgical biopsies of three Killian nasal polyp patients (KNP-MSCs) as well as from their healthy nasal tissue (HNT-MSCs) that were used as controls. The immunophenotype profile of HNT-MSCs and KNP-MSCs was more similar, with a marked positivity for CD73, CD90, and CD105 expression, while being negative for CD34 and CD14 haematopoietic genes. Cell proliferation assay showed that KNP-MSCs had a replicative disadvantage compared to HNT-MSCs, as evidenced by the significantly lower number of cells in the S-phase of the cell cycle. KNP-MSCs also took longer to close a wound than HNT-MSCs, indicating a partial epithelial phenotype in which low levels of ICAM-1 mRNA and a significant increase in E-CAD transcript were detectable. Subsequently, the differentiation potential of both MSCs populations was analyzed by inducing osteoblastic or adipocyte differentiation for up to 20 days. KNP-MSCs showed the ability to differentiate into osteoblasts, although ALP activity as well as the number and size of calcium deposits were lower than osteogenic induced-HNT-MSCs. Also, mRNA levels of osteoblastic marker genes (OCN, OPN, OSX, RUNX2) resulted lower compared to control cell population. Instead, the analysis of the adipogenic differentiation potential showed a similar behavior between KNP-MSCs and HNT-MSCs considering that the amount of lipid droplets, the expression of adipocyte-specific genes (FABP4, AdipoQ, PPARγ2, LPL) and the content of triacylglycerols were almost overlapping. Taken together, these results first demonstrated that Killian's nasal polyp is a source of mesenchymal stem cells with self-renewal and multi-differentiative capabilities.Keywords: Mesenchymal stem cells, adipogenic differentiation, osteogenic differentiation, EMT
Procedia PDF Downloads 777944 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
Procedia PDF Downloads 4767943 An Electron Microscopic Study of Developing Human Fetal Pancreas
Authors: Gupta Renu, T. S. Roy
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Introduction: For the prospect of successful replacement therapies in treatment of Diabetes mallitus it is necessary to know events occurring during normal human pancreas development. Literature of human pancreas development are few in number as well as mainly related to first trimester because of ethical and technical difficulties. So the study was conducted on 12 fetuses from 12 gestational weeks (GW) to 5 months of infant to know normal development of exocrine and endocrine part of human pancreas. Material and Methods: Human fetalpancreases were screened by haematoxyline and eosin staining and done electron microscopy for suitable specimens to know ultrastructural detail of fetal pancreas. Results:It was observed arborized tubules, the cells budding out from these tubules differentiated into primitive acini and islets in 12thGW. At 14 weeks scanty granules were observed in the endocrine cells which coincided with the capillary invasion of the islets. The ducts and acini were surrounded by well-organized connective tissue. The acinihad elongated cells, small amount of cytoplasm and large open face euchromatic nuclei with single nucleolus. The mature form of islets of Langerhans was observed close to the acini and duct in 20 GW fetus. Connective tissue around the duct was well organized.No significant developmental change was observed early postnatal, infant. Conclusion: The development of both component exocrine as well as endocrine part of human fetal pancreas was studied by light and electron microscopy. Observations suggested that the fetal pancreas contained mainly ducts, few acini, many centroacinar cells, and large undifferentiated tissue.Keywords: gestational weeks (GW), acini, islets of Langerhans, ducts
Procedia PDF Downloads 2637942 Investigating Role of Autophagy in Cispaltin Induced Stemness and Chemoresistance in Oral Squamous Cell Carcinoma
Authors: Prajna Paramita Naik, Sujit Kumar Bhutia
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Background: Regardless of the development multimodal treatment strategies, oral squamous cell carcinoma (OSCC) is often associated with a high rate of recurrence, metastasis and chemo- and radio- resistance. The present study inspected the relevance of CD44, ABCB1 and ADAM17 expression as a putative stem cell compartment in oral squamous cell carcinoma (OSCC) and deciphered the role of autophagy in regulating the expression of aforementioned proteins, stemness and chemoresistance. Methods: A retrospective analysis of CD44, ABCB1 and ADAM17 expression with respect to the various clinicopathological factors of sixty OSCC patients were determined via immunohistochemistry. The correlation among CD44, ABCB1 and ADAM17 expression was established. Sphere formation assay, flow cytometry and fluorescence microscopy were conducted to elucidate the stemness and chemoresistance nature of established cisplatin-resistant oral cancer cells (FaDu). The pattern of expression of CD44, ABCB1 and ADAM17 in parental (FaDu-P) and resistant FaDu cells (FaDu-CDDP-R) were investigated through fluorescence microscopy. Western blot analysis of autophagy marker proteins was performed to compare the status of autophagy in parental and resistant FaDu cell. To investigate the role of autophagy in chemoresistance and stemness, sphere formation assay, immunofluorescence and Western blot analysis was performed post transfection with siATG14 and the level of expression of autophagic proteins, mitochondrial protein and stemness-associated proteins were analyzed. The statistical analysis was performed by GraphPad Prism 4.0 software. p-value was defined as follows: not significant (n.s.): p > 0.05;*: p ≤ 0.05; **: p ≤ 0.01; ***: p ≤ 0.001; ****: p ≤ 0.0001 were considered statistically significant. Results: In OSCC, high CD44, ABCB1 and ADAM17 expression were significantly correlated with higher tumor grades and poor differentiation. However, the expression of these proteins was not related to the age and sex of OSCC patients. Moreover, the expression of CD44, ABCB1 and ADAM17 were positively correlated with each other. In vitro and OSCC tissue double labeling experiment data showed that CD44+ cells were highly associated with ABCB1 and ADAM17 expression. Further, FaDu-CDDP-R cells showed higher sphere forming capacity along with increased fraction of the CD44+ population and β-catenin expression FaDu-CDDP-R cells also showed accelerated expression of CD44, ABCB1 and ADAM17. A comparatively higher autophagic flux was observed in FaDu-CDDP-R against FaDu-P cells. The expression of mitochondrial proteins was noticeably reduced in resistant cells as compared to parental cells indicating the occurrence of autophagy-mediated mitochondrial degradation in oral cancer. Moreover, inhibition of autophagy was coupled with the decreased formation of orospheres suggesting autophagy-mediated stemness in oral cancer. Blockade of autophagy was also found to induce the restoration of mitochondrial proteins in FaDu-CDDP-R cells indicating the involvement of mitophagy in chemoresistance. Furthermore, a reduced expression of CD44, ABCB1 and ADAM17 was also observed in ATG14 deficient cells FaDu-P and FaDu-CDDP-R cells. Conclusion: The CD44+ ⁄ABCB1+ ⁄ADAM17+ expression in OSCC might be associated with chemoresistance and a putative CSC compartment. Further, the present study highlights the contribution of mitophagy in chemoresistance and confirms the potential involvement of autophagic regulation in acquisition of stem-like characteristics in OSCC.Keywords: ABCB1, ADAM17, autophagy, CD44, chemoresistance, mitophagy, OSCC, stemness
Procedia PDF Downloads 1957941 Sound Absorbing and Thermal Insulating Properties of Natural Fibers (Coir/Jute) Hybrid Composite Materials for Automotive Textiles
Authors: Robel Legese Meko
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Natural fibers have been used as end-of-life textiles and made into textile products which have become a well-proven and effective way of processing. Nowadays, resources to make primary synthetic fibers are becoming less and less as the world population is rising. Hence it is necessary to develop processes to fabricate textiles that are easily converted to composite materials. Acoustic comfort is closely related to the concept of sound absorption and includes protection against noise. This research paper presents an experimental study on sound absorption coefficients, for natural fiber composite materials: a natural fiber (Coir/Jute) with different blend proportions of raw materials mixed with rigid polyurethane foam as a binder. The natural fiber composite materials were characterized both acoustically (sound absorption coefficient SAC) and also in terms of heat transfer (thermal conductivity). The acoustic absorption coefficient was determined using the impedance tube method according to the ASTM Standard (ASTM E 1050). The influence of the structure of these materials on the sound-absorbing properties was analyzed. The experimental results signify that the porous natural coir/jute composites possess excellent performance in the absorption of high-frequency sound waves, especially above 2000 Hz, and didn’t induce a significant change in the thermal conductivity of the composites. Thus, the sound absorption performances of natural fiber composites based on coir/jute fiber materials promote environmentally friendly solutions.Keywords: coir/jute fiber, sound absorption coefficients, compression molding, impedance tube, thermal insulating properties, SEM analysis
Procedia PDF Downloads 1137940 Assessment of HIV/Hepatitis B Virus Co-Infection among Patients Living with HIV in Northern and Southern Region of Nigeria
Authors: Folajinmi Oluwasina, Greg Abiaziem, Moses Luke, Mobolaji Kolawole, Nancy Yibowei, Anne Taiwo
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Background: Occurrence of HIV infection has an adverse effect on the natural causes of Hepatitis B Viral (HBV) infection, faster progression of hepatic fibrosis demonstrated in patients with co-infection. This study was carried out to determine the incidence of HBV infection among HIV-positive patients, and to retrospectively evaluate laboratory characteristics of patients with HIV/HBV co-infection. Methods: A retrospective analysis of patient files for all HIV-infected cases followed-up and treated at 52 health facilities. Among HIV-infected cases, those with HBsAg positivity and HIV/Hepatitis B co-infection were determined. Socio demographic, alcohol or substance use, ART, CD4, Viral Load levels and treatment durations were retrospectively evaluated. Results: Of the 125 HIV-infected patients evaluated retrospectively, 17 (13.6%) had HBsAg positivity. Of these 17 cases were 11(64.7%) male and 6 (35.3%) female, with a mean age of 48.7 years. No patients had a history of alcohol or substance use. The mean duration of follow up was 28 months. 9 (52.9%) patients had negative HBV DNA at presentation while 8(47%) had positive HBV DNA, with normal ALT levels in all subjects. Among the 9 cases with negative HBV DNA who had no indication for the treatment of chronic hepatitis B. In five cases, treatment was commenced since HBV DNA was elevated in conjunction with low CD4. One patient in whom treatment was not indicated based on HBV DNA and CD4 levels in conjunction with the absence of AIDS defining clinical picture was currently being followed-up without treatment. Of the patients receiving HAART therapy, the average CD4 count at presentation was 278 cells/mm3 vs. 466 cells/mm3 at the end of 12 months. In three subjects with positive HBV DNA, a decrease in HBV DNA was noted after initiation of treatment. In four patients with negative DNA who received treatment, the HBV DNA negative status was found to remain, while one patient who did not receive treatment had elevated HBV DNA and decreased CD4 levels. Conclusion: It was shown that this group of patients with HIV/HBV co-infection, HAART was found to be associated with a decrease in HBV DNA in HBV DNA positive cases, absence of transition to positivity among those with negative HBV DNA, and with increased CD4 in all subjects.Keywords: Hepatitis B, DNA, anti retroviral therapy, co-infection
Procedia PDF Downloads 2707939 Combined PV Cooling and Nighttime Power Generation through Smart Thermal Management of Photovoltaic–Thermoelectric Hybrid Systems
Authors: Abdulrahman M. Alajlan, Saichao Dang, Qiaoqiang Gan
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Photovoltaic (PV) cells, while pivotal for solar energy harnessing, confront a challenge due to the presence of persistent residual heat. This thermal energy poses significant obstacles to the performance and longevity of PV cells. Mitigating this thermal issue is imperative, particularly in tropical regions where solar abundance coexists with elevated ambient temperatures. In response, a sustainable and economically viable solution has been devised, incorporating water-passive cooling within a Photovoltaic-Thermoelectric (PV-TEG) hybrid system to address PV cell overheating. The implemented system has significantly reduced the operating temperatures of PV cells, achieving a notable reduction of up to 15 °C below the temperature observed in standalone PV systems. In addition, a thermoelectric generator (TEG) integrated into the system significantly enhances power generation, particularly during nighttime operation. The developed hybrid system demonstrates its capability to generate power at a density of 0.5 Wm⁻² during nighttime, which is sufficient to concurrently power multiple light-emitting diodes, demonstrating practical applications for nighttime power generation. Key findings from this research include a consistent temperature reduction exceeding 10 °C for PV cells, translating to a 5% average enhancement in PV output power compared to standalone PV systems. Experimental demonstrations underscore nighttime power generation of 0.5 Wm⁻², with the potential to achieve 0.8 Wm⁻² through simple geometric optimizations. The optimal cooling of PV cells is determined by the volume of water in the heat storage unit, exhibiting an inverse relationship with the optimal performance for nighttime power generation. Furthermore, the TEG output effectively powers a lighting system with up to 5 LEDs during the night. This research not only proposes a practical solution for maximizing solar radiation utilization but also charts a course for future advancements in energy harvesting technologies.Keywords: photovoltaic-thermoelectric systems, nighttime power generation, PV thermal management, PV cooling
Procedia PDF Downloads 877938 Pedagogical Technologies of Teaching Natural Geography
Authors: Mirzahmedov Ismoiljon Karimjon Ugli, Juraeva Shakhnoza Abdumalik Kizi
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The article deals with the current scientific problems of natural geography related to the development of new pedagogical technologies and their implementation in the educational process. The use of recommended interactive methods in independent study is considered very effective and is a very useful method for students, especially for students who work more on themselves. Today's demand is to make young people talented, intelligent, innovative, as well as mature and well-rounded individuals, as a result of the work carried out in the field of education today. This is how creating tables of different contents and filling them out shows the student's talent and desire for innovation. Also, the techniques and methods necessary for today's student are shown, the role of the teacher in conducting lessons meaningfully, the suitability of the method used by the teacher for the lesson, factors affecting the quality of education, and natural issues of the use of methods based on the specific features of geography are highlighted.Keywords: teaching methods, educational process, educational technologies, education, problem, didactics, natural geography
Procedia PDF Downloads 677937 ESDN Expression in the Tumor Microenvironment Coordinates Melanoma Progression
Authors: Roberto Coppo, Francesca Orso, Daniela Dettori, Elena Quaglino, Lei Nie, Mehran M. Sadeghi, Daniela Taverna
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Malignant melanoma is currently the fifth most common cancer in the white population and it is fatal in its metastatic stage. Several research studies in recent years have provided evidence that cancer initiation and progression are driven by genetic alterations of the tumor and paracrine interactions between tumor and microenvironment. Scattered data show that the Endothelial and Smooth muscle cell-Derived Neuropilin-like molecule (ESDN) controls cell proliferation and movement of stroma and tumor cells. To investigate the role of ESDN in the tumor microenvironment during melanoma progression, murine melanoma cells (B16 or B16-F10) were injected in ESDN knockout mice in order to evaluate how the absence of ESDN in stromal cells could influence melanoma progression. While no effect was found on primary tumor growth, increased cell extravasation and lung metastasis formation was observed in ESDN knockout mice compared to wild type controls. In order to understand how cancer cells cross the endothelial barrier during metastatic dissemination in an ESDN-null microenvironment, structure, and permeability of lung blood vessels were analyzed. Interestingly, ESDN knockout mice showed structurally altered and more permeable vessels compared to wild type animals. Since cell surface molecules mediate the process of tumor cell extravasation, the expression of a panel of extravasation-related ligands and receptors was analyzed. Importantly, modulations of N-cadherin, E-selectin, ICAM-1 and VAP-1 were observed in ESDN knockout endothelial cells, suggesting the presence of a favorable tumor microenvironment which facilitates melanoma cell extravasation and metastasis formation in the absence of ESDN. Furthermore, a potential contribution of immune cells in tumor dissemination was investigated. An increased recruitment of macrophages in the lungs of ESDN knockout mice carrying subcutaneous B16-F10 tumors was found. In conclusion, our data suggest a functional role of ESDN in the tumor microenvironment during melanoma progression and the identification of the mechanisms that regulate tumor cell extravasation could lead to the development of new therapies to reduce metastasis formation.Keywords: melanoma, tumor microenvironment, extravasation, cell surface molecules
Procedia PDF Downloads 3357936 CCR5 as an Ideal Candidate for Immune Gene Therapy and Modification for the Induced Resistance to HIV-1 Infection
Authors: Alieh Farshbaf, Tayyeb Bahrami
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Introduction: Cc-chemokine receptor-5 (CCR5) is known as a main co-receptor in human immunodeficiency virus type-1 (HIV-1) infection. Many studies showed 32bp deletion (Δ32) in CCR5 gene, provide natural resistance to HIV-1 infection in homozygous individuals. Inducing the resistance mechanism by CCR5 in HIV-1 infected patients eliminated many problems of highly-active-anti retroviral therapy (HAART) drugs like as low safety, side-effects and virus rebounding from latent reservoirs. New treatments solved some restrictions that are based on gene modification and cell therapy. Literature review: The stories of the “Berlin and Boston patients” showed autologous hematopoietic stem cells transplantation (HSCT) could provide effective cure of HIV-1 infected patients. Furthermore, gene modification by zinc finger nuclease (ZFN) demonstrated another successful result again. Despite the other studies for gene therapy by ∆32 genotype, there is another mutation -CCR5 ∆32/m303- that provides HIV-1 resistant. It is a heterozygote genotype for ∆32 and T→A point mutation at nucleotide 303. These results approved the key role of CCR5 gene. Conclusion: Recent studies showed immune gene therapy and cell therapy could provide effective cure for refractory disease like as HIV. Eradication of HIV-1 from immune system was not observed by HAART, because of reloading virus genome from latent reservoirs after stopping them. It is showed that CCR5 could induce natural resistant to HIV-1 infection by the new approaches based on stem cell transplantation and gene modifying.Keywords: CCR5, HIV-1, stem cell, immune gene therapy, gene modification
Procedia PDF Downloads 2907935 A Survey of the Applications of Sentiment Analysis
Authors: Pingping Lin, Xudong Luo
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Natural language often conveys emotions of speakers. Therefore, sentiment analysis on what people say is prevalent in the field of natural language process and has great application value in many practical problems. Thus, to help people understand its application value, in this paper, we survey various applications of sentiment analysis, including the ones in online business and offline business as well as other types of its applications. In particular, we give some application examples in intelligent customer service systems in China. Besides, we compare the applications of sentiment analysis on Twitter, Weibo, Taobao and Facebook, and discuss some challenges. Finally, we point out the challenges faced in the applications of sentiment analysis and the work that is worth being studied in the future.Keywords: application, natural language processing, online comments, sentiment analysis
Procedia PDF Downloads 2637934 Modelling and Simulation of Light and Temperature Efficient Interdigitated Back- Surface-Contact Solar Cell with 28.81% Efficiency Rate
Authors: Mahfuzur Rahman
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Back-contact solar cells improve optical properties by moving all electrically conducting parts to the back of the cell. The cell's structure allows silicon solar cells to surpass the 25% efficiency barrier and interdigitated solar cells are now the most efficient. In this work, the fabrication of a light, efficient and temperature resistant interdigitated back contact (IBC) solar cell is investigated. This form of solar cell differs from a conventional solar cell in that the electrodes are located at the back of the cell, eliminating the need for grids on the top, allowing the full surface area of the cell to receive sunlight, resulting in increased efficiency. In this project, we will use SILVACO TCAD, an optoelectronic device simulator, to construct a very thin solar cell with dimensions of 100x250um in 2D Luminous. The influence of sunlight intensity and atmospheric temperature on solar cell output power is highly essential and it has been explored in this work. The cell's optimum performance with 150um bulk thickness provides 28.81% efficiency with an 87.68% fill factor rate making it very thin, flexible and resilient, providing diverse operational capabilities.Keywords: interdigitated, shading, recombination loss, incident-plane, drift-diffusion, luminous, SILVACO
Procedia PDF Downloads 1467933 Single Cell Analysis of Circulating Monocytes in Prostate Cancer Patients
Authors: Leander Van Neste, Kirk Wojno
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The innate immune system reacts to foreign insult in several unique ways, one of which is phagocytosis of perceived threats such as cancer, bacteria, and viruses. The goal of this study was to look for evidence of phagocytosed RNA from tumor cells in circulating monocytes. While all monocytes possess phagocytic capabilities, the non-classical CD14+/FCGR3A+ monocytes and the intermediate CD14++/FCGR3A+ monocytes most actively remove threatening ‘external’ cellular materials. Purified CD14-positive monocyte samples from fourteen patients recently diagnosed with clinically localized prostate cancer (PCa) were investigated by single-cell RNA sequencing using the 10X Genomics protocol followed by paired-end sequencing on Illumina’s NovaSeq. Similarly, samples were processed and used as controls, i.e., one patient underwent biopsy but was found not to harbor prostate cancer (benign), three young, healthy men, and three men previously diagnosed with prostate cancer that recently underwent (curative) radical prostatectomy (post-RP). Sequencing data were mapped using 10X Genomics’ CellRanger software and viable cells were subsequently identified using CellBender, removing technical artifacts such as doublets and non-cellular RNA. Next, data analysis was performed in R, using the Seurat package. Because the main goal was to identify differences between PCa patients and ‘control’ patients, rather than exploring differences between individual subjects, the individual Seurat objects of all 21 patients were merged into one Seurat object per Seurat’s recommendation. Finally, the single-cell dataset was normalized as a whole prior to further analysis. Cell identity was assessed using the SingleR and cell dex packages. The Monaco Immune Data was selected as the reference dataset, consisting of bulk RNA-seq data of sorted human immune cells. The Monaco classification was supplemented with normalized PCa data obtained from The Cancer Genome Atlas (TCGA), which consists of bulk RNA sequencing data from 499 prostate tumor tissues (including 1 metastatic) and 52 (adjacent) normal prostate tissues. SingleR was subsequently run on the combined immune cell and PCa datasets. As expected, the vast majority of cells were labeled as having a monocytic origin (~90%), with the most noticeable difference being the larger number of intermediate monocytes in the PCa patients (13.6% versus 7.1%; p<.001). In men harboring PCa, 0.60% of all purified monocytes were classified as harboring PCa signals when the TCGA data were included. This was 3-fold, 7.5-fold, and 4-fold higher compared to post-RP, benign, and young men, respectively (all p<.001). In addition, with 7.91%, the number of unclassified cells, i.e., cells with pruned labels due to high uncertainty of the assigned label, was also highest in men with PCa, compared to 3.51%, 2.67%, and 5.51% of cells in post-RP, benign, and young men, respectively (all p<.001). It can be postulated that actively phagocytosing cells are hardest to classify due to their dual immune cell and foreign cell nature. Hence, the higher number of unclassified cells and intermediate monocytes in PCa patients might reflect higher phagocytic activity due to tumor burden. This also illustrates that small numbers (~1%) of circulating peripheral blood monocytes that have interacted with tumor cells might still possess detectable phagocytosed tumor RNA.Keywords: circulating monocytes, phagocytic cells, prostate cancer, tumor immune response
Procedia PDF Downloads 1627932 Evaluation of the Cytotoxicity and Cellular Uptake of a Cyclodextrin-Based Drug Delivery System for Cancer Therapy
Authors: Caroline Mendes, Mary McNamara, Orla Howe
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Drug delivery systems are proposed for use in cancer treatment to specifically target cancer cells and deliver a therapeutic dose without affecting normal cells. For that purpose, the use of folate receptors (FR) can be considered a key strategy, since they are commonly over-expressed in cancer cells. In this study, cyclodextrins (CD) have being used as vehicles to target FR and deliver the chemotherapeutic drug, methotrexate (MTX). CDs have the ability to form inclusion complexes, in which molecules of suitable dimensions are included within their cavities. Here, β-CD has been modified using folic acid so as to specifically target the FR. Thus, this drug delivery system consists of β-CD, folic acid and MTX (CDEnFA:MTX). Cellular uptake of folic acid is mediated with high affinity by folate receptors while the cellular uptake of antifolates, such as MTX, is mediated with high affinity by the reduced folate carriers (RFCs). This study addresses the gene (mRNA) and protein expression levels of FRs and RFCs in the cancer cell lines CaCo-2, SKOV-3, HeLa, MCF-7, A549 and the normal cell line BEAS-2B, quantified by real-time polymerase chain reaction (real-time PCR) and flow cytometry, respectively. From that, four cell lines with different levels of FRs, were chosen for cytotoxicity assays of MTX and CDEnFA:MTX using the MTT assay. Real-time PCR and flow cytometry data demonstrated that all cell lines ubiquitously express moderate levels of RFC. These experiments have also shown that levels of FR protein in CaCo-2 cells are high, while levels in SKOV-3, HeLa and MCF-7 cells are moderate. A549 and BEAS-2B cells express low levels of FR protein. FRs are highly expressed in all the cancer cell lines analysed when compared to the normal cell line BEAS-2B. The cell lines CaCo-2, MCF-7, A549 and BEAS-2B were used in the cell viability assays. 48 hours treatment with the free drug and the complex resulted in IC50 values of 93.9 µM ± 15.2 and 56.0 µM ± 4.0 for CaCo-2 for free MTX and CDEnFA:MTX respectively, 118.2 µM ± 16.8 and 97.8 µM ± 12.3 for MCF-7, 36.4 µM ± 6.9 and 75.0 µM ± 10.5 for A549 and 132.6 µM ± 16.1 and 288.1 µM ± 26.3 for BEAS-2B. These results demonstrate that free MTX is more toxic towards cell lines expressing low levels of FR, such as the BEAS-2B. More importantly, these results demonstrate that the inclusion complex CDEnFA:MTX showed greater cytotoxicity than the free drug towards the high FR expressing CaCo-2 cells, indicating that it has potential to target this receptor, enhancing the specificity and the efficiency of the drug. The use of cell imaging by confocal microscopy has allowed visualisation of FR targeting in cancer cells, as well as the identification of the interlisation pathway of the drug. Hence, the cellular uptake and internalisation process of this drug delivery system is being addressed.Keywords: cancer treatment, cyclodextrins, drug delivery, folate receptors, reduced folate carriers
Procedia PDF Downloads 3117931 Biobased Toughening Filler for Polylactic Acid from Ultrafine Fully Vulcanized Powder Natural Rubber Grafted with Polymethylmethacrylate
Authors: Panyawutthi Rimdusit, Krittapas Charoensuk, Sarawut Rimdusit
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A biobased toughening filler for polylactic acid (PLA) based on natural rubber is developed in this work. Deproteinized natural rubber (DPNR) was modified by grafting polymerization with methyl methacrylate monomer (MMA) and further crosslinked by e-beam irradiation and spray drying process to achieve ultrafine full vulcanized powdered natural rubber grafted with polymethylmethacrylate (UFPNRg-PMMA) to solves in the challenges of incompatibility between natural rubber and PLA. Intriguingly, UFPNR-g-PMMA revealed outstanding and unique properties with minimal particle aggregation. The average particle size of rubber powder obtained from UFPNR-g-PMMA at PMMA grafting content of 20 phr reduced to 3.3±1.2 µm, compared to that of neat UFPNR of 5.3±2.3 µm which also showed partial particle aggregation. It is also found that the impact strength of the filled PLA was enhanced to 33.4±5.6 kJ/m2 at PLA/UFPNR-gPMMA 20 wt% compared to neat PLA of 9.6±3 kJ/m2. The thermal degradation temperature of the PLA composites was enhanced with increasing UFPNR-g-PMMA content without affecting the glass transition temperature of the composites. The fracture surface of PLA/ UFPNR-g-PMMA suggested internal cavitation and crazes are the main effects of rubber toughening PLA with substantial interfacial interaction between the filler and the matrix.Keywords: natural rubber, ultrafine fully vulcanized powder rubber, polylactic acid, polymer composites
Procedia PDF Downloads 147930 Anti-Oxidant and Anti-Cancer Activity of Helix aspersa Aqueous Extract
Authors: Ibtissem El Ouar, Cornelia Braicu, Dalila Naimi, Alexendru Irimie, Ioana Berindan-Neagoe
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Helix aspersa, 'the garden snail' is a big land snail widely found in the Mediterranean countries, it is one of the most consumed species in the west of Algeria. It is commonly used in zootherapy to purify blood and to treat cardiovascular diseases and liver problems. The aim of our study is to investigate, the antitumor activity of an aqueous extract from Helix aspersa prepared by the traditional method on Hs578T; a triple negative breast cancer cell line. Firstly, the free radical scavenging activity of H. aspersa extract was assessed by measuring its capability for scavenging the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), as well as its ability to reduce ferric ion by the FRAP assay (ferric reducing ability). The cytotoxic effect of H. aspersa extract against Hs578T cells was evaluated by the MTT test (3-(4,5- dimethylthiazl-2-yl)-2,5- diphenyltetrazolium bromide)) while the mode of cell death induced by the extract has been determined by fluorescence microscopy using acredine orange/ethidium bromide (AO/EB) probe. The level of TNFα has also measured in cell medium by ELISA method. The results suggest that H. aspersa extract has an antioxidant activity, especially at high concentrations, it can reduce DPPH radical and ferric ion. The MTT test shows that H. aspersa extract has a great cytotoxic effect against breast cancer cells, the IC50 value correspond of the dilution 1% of the crude extract. Moreover, the AO/EB staining shows that TNFα induced necrosis is the main form of cell death induced by the extract. In conclusion, the present study may open new perspectives in the search for new natural anticancer drugs.Keywords: breast cancer, Helix aspersa, Hs578t cell line, necrosis
Procedia PDF Downloads 4237929 PPRA Regulates DNA Replication Initiation and Cell Morphology in Escherichia coli
Authors: Ganesh K. Maurya, Reema Chaudhary, Neha Pandey, Hari S. Misra
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PprA, a pleiotropic protein participating in radioresistance, has been reported for its roles in DNA replication initiation, genome segregation, cell division and DNA repair in polyextremophile Deinococcus radiodurans. Interestingly, expression of deinococcal PprA in E. coli suppresses its growth by reducing the number of colony forming units and provides better resistance against γ-radiation than control. We employed different biochemical and cell biology studies using PprA and its DNA binding/polymerization mutants (K133E & W183R) in E. coli. Cells expressing wild type PprA or its K133E mutant showed reduction in the amount of genomic DNA as well as chromosome copy number in comparison to W183R mutant of PprA and control cells, which suggests the role of PprA protein in regulation of DNA replication initiation in E. coli. Further, E. coli cells expressing PprA or its mutants exhibited different impact on cell morphology than control. Expression of PprA or K133E mutant displayed a significant increase in cell length upto 5 folds while W183R mutant showed cell length similar to uninduced control cells. We checked the interaction of deinococcal PprA and its mutants with E. coli DnaA using Bacterial two-hybrid system and co-immunoprecipitation. We observed a functional interaction of EcDnaA with PprA and K133E mutant but not with W183R mutant of PprA. Further, PprA or K133E mutant has suppressed the ATPase activity of EcDnaA but W183R mutant of PprA failed to do so. These observations suggested that PprA protein regulates DNA replication initiation and cell morphology of surrogate E. coli.Keywords: DNA replication, radioresistance, protein-protein interaction, cell morphology, ATPase activity
Procedia PDF Downloads 697928 Synergistic Effect of Doxorubicin-Loaded Silver Nanoparticles – Polymeric Conjugates on Breast Cancer Cells
Authors: Nancy M. El-Baz, Laila Ziko, Rania Siam, Wael Mamdouh
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Cancer is one of the most devastating diseases, and has over than 10 million new cases annually worldwide. Despite the effectiveness of chemotherapeutic agents, their systemic toxicity and non-selective anticancer actions represent the main obstacles facing cancer curability. Due to the effective enhanced permeability and retention (EPR) effect of nanomaterials, nanoparticles (NPs) have been used as drug nanocarriers providing targeted cancer drug delivery systems. In addition, several inorganic nanoparticles such as silver (AgNPs) nanoparticles demonstrated a potent anticancer activity against different cancers. The present study aimed at formulating core-shell inorganic NPs-based combinatorial therapy based on combining the anticancer activity of AgNPs along with doxorubicin (DOX) and evaluating their cytotoxicity on MCF-7 breast cancer cells. These inorganic NPs-based combinatorial therapies were designed to (i) Target and kill cancer cells with high selectivity, (ii) Have an improved efficacy/toxicity balance, and (iii) Have an enhanced therapeutic index when compared to the original non-modified DOX with much lower dosage The in-vitro cytotoxicity studies demonstrated that the NPs-based combinatorial therapy achieved the same efficacy of non-modified DOX on breast cancer cell line, but with 96% reduced dose. Such reduction in DOX dose revealed that the combination between DOX and NPs possess a synergic anticancer activity against breast cancer. We believe that this is the first report on a synergic anticancer effect at very low dose of DOX against MCF-7 cells. Future studies on NPs-based combinatorial therapy may aid in formulating novel and significantly more effective cancer therapeutics.Keywords: nanoparticles-based combinatorial therapy, silver nanoparticles, doxorubicin, breast cancer
Procedia PDF Downloads 437