Search results for: regulatory T cells
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3884

Search results for: regulatory T cells

1334 Effect of Lactone Glycoside on Feeding Deterrence and Nutritive Physiology of Tobacco Caterpillar Spodoptera litura Fabricius (Noctuidae: Lepidoptera)

Authors: Selvamuthukumaran Thirunavukkarasu, Arivudainambi Sundararajan

Abstract:

The plant active molecules with their known mode of action are important leads to the development of newer insecticides. Lactone glycoside was identified earlier as the active principle in Cleistanthus collinus (Roxb.) Benth. (Fam: Euphorbiaceae). It possessed feeding deterrent, insecticidal and insect growth regulatory actions at varying concentrations. Deducing its mode of action opens a possibility of its further development. A no-choice leaf disc bioassay was carried out with lactone glycoside at different doses for different instars and Deterrence Indices were worked out. Using regression analysis concentrations imparting 10, 30 and 50 per cent deterrence (DI10, DI30 & DI50) were worked out. At these doses, effect on nutritional indices like Relative Consumption and Growth Rates (RCR & RGR), Efficiencies of Conversion of Ingested and Digested food (ECI & ECD) and Approximate Digestibility (AD) were worked out. The Relative Consumption and Growth Rate of control and lactone glycoside larva were compared by regression analysis. Regression analysis of deterrence indices revealed that the concentrations needed for imparting 50 per cent deterrence was 60.66, 68.47 and 71.10 ppm for third, fourth and fifth instars respectively. Relative consumption rate (RCR) and relative growth rate (RGR) were reduced. This confirmed the antifeedant action of the fraction. Approximate digestibility (AD) was found greater in treatments indicating reduced faeces because of poor digestibility and retention of food in the gut. Efficiency of conversion of both ingested and digested (ECI and ECD) food was also found to be greatly reduced. This indicated presence of toxic action. This was proved by comparing growth efficiencies of control and lactone glycoside treated larvae. Lactone glycoside was found to possess both feeding deterrent and toxic modes of action. Studies on molecular targets based on this preliminary site of action lead to new insecticide development.

Keywords: Spodoptera litura Fabricius, Cleistanthus collinus (Roxb.) Benth, feeding deterrence, mode of action

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1333 Rethinking Urban Informality through the Lens of Inclusive Planning and Governance in Contemporary Cities: A Case Study of Johannesburg, South Africa

Authors: Blessings Masuku

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Background: Considering that Africa is urbanizing faster than any other region globally, managing cities in the global South has become the centerpiece for the New Urban Agenda (i.e., a shared vision of how we rethink, rebuild, and manage our cities for a better and more sustainable future). This study is centered on governance and planning of urban informality practices with particular reference to the relationship between the state, informal actors (e.g., informal traders and informal dwellers), and other city stakeholders who are public space users (commuters, businesses, and environmental activists), and how informal actors organize themselves to lobby the state and claim for their rights in the city, and how they navigate their everyday livelihood strategies. Aim: The purpose of this study is to examine and interrogate contemporary approaches, policy and regulatory frameworks to urban spatial planning and management of informality in one of South Africa’s busiest and major cities, Johannesburg. Setting: The study uses the metropolitan region of the city of Johannesburg, South Africa to understand how this contemporary industrial city manages urban informality practices, including the use of public space, land zoning and street life, and paying a closer look at what progress has been made and gaps in their inclusive urban policy frameworks. Methods: This study utilized a qualitative approach that includes surveys (open-ended questions), archival research (i., e policy and other key document reviews), and key interviews mainly with city officials, and informality actors. A thematic analysis was used to analyze the data collected. Contribution: This study contributes to large urban informality scholarship in the global South cities by exploring how major cities particularly in Africa regulate and manage informality patterns and practices in their quest to build “utopian” smart cities. This study also brings a different perspective on the hacking ways used by the informal actors to resist harsh regulations and remain invisible in the city, which is something that previous literature has barely delved in-depth.

Keywords: inclusive planning and governance, infrastructure systems, livelihood strategies urban informality, urban space

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1332 Laboratory Calibration of Soil Pressure Transducer for a Specified Field Application

Authors: Mohammad Zahidul Islam Bhuiyan, Shanyong Wang, Scott William Sloan, Daichao Sheng

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Nowadays soil pressure transducers are widely used to measure the soil stress states in laboratory and field experiments. The soil pressure transducers, investigated here, are traditional diaphragm-type earth pressure cells (DEPC) based on strain gauge principle. It is found that the output of these sensors varies with the soil conditions as well as the position of a sensor. Therefore, it is highly recommended to calibrate the pressure sensors based on the similar conditions of their intended applications. The factory calibration coefficients of the EPCs are not reliable to use since they are normally calibrated by applying fluid (a special type of oil) pressure only over load sensing zone, which does not represent the actual field conditions. Thus, the calibration of these sensors is utmost important, and they play a pivotal role for assessing earth pressures precisely. In the present study, TML soil pressure sensor is used to compare its sensitivity under different calibration systems, for example, fluid calibration, and static load calibration with or without soil. The results report that the sensor provides higher sensitivity (more accurate results) under soil calibration system.

Keywords: calibration, soil pressure, earth pressure cell, sensitivity

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1331 Design of Liquid Crystal Based Tunable Reflectarray Antenna Using Slot Embedded Patch Element Configurations

Authors: M. Y. Ismail, M. Inam

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This paper presents the design and analysis of Liquid Crystal (LC) based tunable reflect array antenna with different design configurations within X-band frequency range. The effect of LC volume used for unit cell element on frequency tunability and reflection loss performance has been investigated. Moreover different slot embedded patch element configurations have been proposed for LC based tunable reflect array antenna design with enhanced performance. The detailed fabrication and measurement procedure for different LC based unit cells has been presented. The waveguide scattering parameter measured results demonstrated that by using the circular slot embedded patch elements, the frequency tunability and dynamic phase range can be increased from 180 MHz to 200 MHz and 120° to 124° respectively. Furthermore the circular slot embedded patch element can be designed at 10 GHz resonant frequency with a patch volume of 2.71 mm3 as compared to 3.47 mm3 required for rectangular patch without slot.

Keywords: liquid crystal, tunable reflect array, frequency tunability, dynamic phase range

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1330 Molecular Docking and Synthesis of Nitrogen-Containing Bisphosphonates

Authors: S. Ghalem, M. Mesmoudi, I. Daoudand, H. Allali

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The nitrogen-containing bisphosphonates (N-BPs) are well established as the treatments of choice for disorders of excessive bone resorption, myeloma and bone metastases, and osteoporosis. They inhibit farnesyl pyrophosphate synthase (FFPS), a key enzyme in the mevalonate pathway, resulting in inhibition of the prenylation of small GTP-binding proteins in osteoclasts and disruption of their cytoskeleton, adhesion/spreading, and invasion of cancer cells. A very few examples for synthesis of α-amino bisphosphonates based on several amino acids are known from the literature. In the present work, esters of aminoacid react with ketophsophonate (or their analog acid or acyl) to afford the desired products, α-iminophosphonates. The reaction of imine with dimethyl phosphate in the presence of catalytic amount of I2 give ester of α-aminobisphosphonate as sole product in good yield. Finally, we used computational docking methods to predict how several α-aminobisphosphonates bind to FPPS and how R and X influence. Pamidronate, β-aminobisphosphonate already marketed, was used as reference. These results are of interest since they represent a new and simple way to sythesize α-aminobisphosphonates with a free COOH group increased by R2 functionalisable and opening up the possibility of using the molecular docking to facilitate the design of other, novel FFPS inhibitors.

Keywords: drug research, cancer, α-amino bisphosphonates, molecular docking

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1329 Innovative Grafting of Polyvinylpyrrolidone onto Polybenzimidazole Proton Exchange Membranes for Enhanced High-Temperature Fuel Cell Performance

Authors: Zeyu Zhou, Ziyu Zhao, Xiaochen Yang, Ling AI, Heng Zhai, Stuart Holmes

Abstract:

As a promising sustainable alternative to traditional fossil fuels, fuel cell technology is highly favoured due to its enhanced working efficiency and reduced emissions. In the context of high-temperature fuel cells (operating above 100 °C), the most commonly used proton exchange membrane (PEM) is the Polybenzimidazole (PBI) doped phosphoric acid (PA) membrane. Grafting is a promising strategy to advance PA-doped PBI PEM technology. The existing grafting modification on PBI PEMs mainly focuses on grafting phosphate-containing or alkaline groups onto the PBI molecular chains. However, quaternary ammonium-based grafting approaches face a common challenge. To initiate the N-alkylation reaction, deacidifying agents such as NaH, NaOH, KOH, K2CO3, etc., can lead to ionic crosslinking between the quaternary ammonium group and PBI. Polyvinylpyrrolidone (PVP) is another widely used polymer, the N-heterocycle groups within PVP endow it with a significant ability to absorb PA. Recently, PVP has attracted substantial attention in the field of fuel cells due to its reduced environmental impact and impressive fuel cell performance. However, due to the the poor compatibility of PVP in PBI, few research apply PVP in PA-doped PBI PEMs. This work introduces an innovative strategy to graft PVP onto PBI to form a network-like polymer. Due to the absence of quaternary ammonium groups, PVP does not pose issues related to crosslinking with PBI. Moreover, the nitrogen-containing functional groups on PVP provide PBI with a robust phosphoric acid retention ability. The nuclear magnetic resonance (NMR) hydrogen spectrum analysis results indicate the successful completion of the grafting reaction where N-alkylation reactions happen on both sides of the grafting agent 1,4-bis(chloromethyl)benzene. On one side, the reaction takes place with the hydrogen atoms on the imidazole groups of PBI, while on the other side, it reacts with the terminal amino group of PVP. The XPS results provide additional evidence from the perspective of the element. On synthesized PBI-g-PVP surfaces, there is an absence of chlorine (chlorine in grafting agent 1,4-bis(chloromethyl)benzene is substituted) element but a presence of sulfur element (sulfur element in terminal amino PVP appears in PBI), which demonstrates the occurrence of the grafting reaction and PVP is successfully grafted onto PBI. Prepare these modified membranes into MEA. It was found that during the fuel cell operation, all the grafted membranes showed substantial improvement in maximum current density and peak power density compared to unmodified one. For PBI-g-PVP 30, with a grafting degree of 22.4%, the peak power density reaches 1312 mW cm⁻², marking a 59.6% enhancement compared to the pristine PBI membrane. The improvement is caused by the improved PA binding ability of the membrane after grafting. The AST test result shows that the grafting membranes have better long-term durability and performance than unmodified membranes attributed to the presence of added PA binding sites, which can effectively prevent the PA leaching caused by proton migration. In conclusion, the test results indicate that grafting PVP onto PBI is a promising strategy which can effectively improve the fuel cell performance.

Keywords: fuel cell, grafting modification, PA doping ability, PVP

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1328 Preparation of Novel Antimicrobial Meat Packaging Using Chitosan-Arginine

Authors: R. A. Lahmer, A. P. Williams, S. Townsend, S. Baker, D. L. Jones

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Chitosan-arginine (Ch-arg) has been proposed as an anti-microbial agent to reduce the proliferation of spoilage and pathogenic bacteria within meat products destined for human consumption. In the current experiment its use as an antimicrobial packaging material was examined. Two different concentrations of chitosan-arginine (0.05 and 0.15 % w/w) were blended into a cellulose film (Ch-arg film). When placed in contact with chicken and beef juice inoculated with a lux-marked strain of E. coli O157, the film incorporating the highest Ch-arg concentration resulted in a small reduction of E. coli O157 in chicken juice; however, there was no effect of the Ch-arg film on E. coli O157 in beef juice. The lack of observed effect in the beef juice experiment we ascribe to insufficient surface-to-surface contact between the film and the bacteria in the beef juice and the greater presence of other Ch-arg reactive components in the juice (e.g. fats, blood cells). Results suggest that, in combination with other anti microbials, Ch-arg packaging may offers some potential for limiting the growth of pathogenic bacteria in foodstuffs; however, further research is needed to enhance their anti-microbial performance.

Keywords: cross-contamination, foodborne pathogen, polymer film, shelf life

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1327 Human Microbiome Hidden Association with Chronic and Autoimmune Diseases

Authors: Elmira Davasaz Tabrizi, Müşteba Sevil, Ercan Arican

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In recent decades, there has been a sharp increase in the prevalence of several unrelated chronic diseases. The use of long-term antibiotics for chronic illnesses is increasing. The antibiotic resistance occurrence and its relationship with host microbiomes are still unclear. Properties of the identifying antibodies have been the focus of chronic disease research, such as prostatitis or autoimmune. The immune system is made up of a complicated but well-organized network of cell types that constantly monitor and maintain their surroundings. The regulated homeostatic interaction between immune system cells and their surrounding environment shapes the microbial flora. Researchers believe that the disappearance of special bacterial species from our ancestral microbiota might have altered the body flora that can cause a rise in disease during the human life span. This unpleasant pattern demonstrates the importance of focusing on discovering and revealing the root causes behind the disappearance or alteration of our microbiota. In this review, we gathered the results of some studies that reveal changes in the diversity and quantity of microorganisms that may affect chronic and autoimmune diseases. Additionally, a Ph.D. thesis that is still in process as Metagenomic studies in chronic prostatitis samples is mentioned.

Keywords: metagenomic, autoimmune, prostatitis, microbiome

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1326 The Ethical Imperative of Corporate Social Responsibility Practice and Disclosure by Firms in Nigeria Delta Swamplands: A Qualitative Analysis

Authors: Augustar Omoze Ehighalua, Itotenaan Henry Ogiri

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As a mono-product economy, Nigeria relies largely on oil revenues for its foreign exchange earnings and the exploration activities of firms operating in the Niger Delta region have left in its wake tales of environmental degradation, poverty and misery. This, no doubt, have created corporate social responsibility issues in the region. The focus of this research is the critical evaluation of the ethical response to Corporate Social Responsibility (CSR) practice by firms operating in Nigeria Delta Swamplands. While CSR is becoming more popular in developed society with effective practice guidelines and reporting benchmark, there is a relatively low level of awareness and selective applicability of existing international guidelines to effectively support CSR practice in Nigeria. This study, haven identified the lack of CSR institutional framework attempts to develop an ethically-driven CSR transparency benchmark laced within a regulatory framework based on international best practices. The research adopts a qualitative methodology and makes use of primary data collected through semi-structured interviews conducted across the six core states of the Niger Delta Region. More importantly, the study adopts an inductive, interpretivist philosophical paradigm that reveal deep phenomenological insights into what local communities, civil society and government officials consider as good ethical benchmark for responsible CSR practice by organizations. The institutional theory provides for the main theoretical foundation, complemented by the stakeholder and legitimacy theories. The Nvivo software was used to analyze the data collected. This study shows that ethical responsibility is lacking in CSR practice by firms in the Niger Delta Region of Nigeria. Furthermore, findings of the study indicate key issues of environmental, health and safety, human rights, and labour as fundamental in developing an effective CSR practice guideline for Nigeria. The study has implications for public policy formulation as well as managerial perspective.

Keywords: corporate social responsibility, CSR, ethics, firms, Niger-Delta Swampland, Nigeria

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1325 The Role of Cholesterol Oxidase of Mycobacterium tuberculosis in the Down-Regulation of TLR2-Signaling Pathway in Human Macrophages during Infection Process

Authors: Michal Kielbik, Izabela Szulc-Kielbik, Anna Brzostek, Jaroslaw Dziadek, Magdalena Klink

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The goal of many research groups in the world is to find new components that are important for survival of mycobacteria in the host cells. Mycobacterium tuberculosis (Mtb) possesses a number of enzymes degrading cholesterol that are considered to be an important factor for its survival and persistence in host macrophages. One of them - cholesterol oxidase (ChoD), although not being essential for cholesterol degradation, is discussed as a virulence compound, however its involvement in macrophages’ response to Mtb is still not sufficiently determined. The recognition of tubercle bacilli antigens by pathogen recognition receptors is crucial for the initiation of the host innate immune response. An important receptor that has been implicated in the recognition and/or uptake of Mtb is Toll-like receptor type 2 (TLR2). Engagement of TLR2 results in the activation and phosphorylation of intracellular signaling proteins including IRAK-1 and -4, TRAF-6, which in turn leads to the activation of target kinases and transcription factors responsible for bactericidal and pro-inflammatory response of macrophages. The aim of these studies was a detailed clarification of the role of Mtb cholesterol oxidase as a virulence factor affecting the TLR2 signaling pathway in human macrophages. As human macrophages the THP-1 differentiated cells were applied. The virulent wild-type Mtb strain (H37Rv), its mutant lacking a functional copy of gene encoding cholesterol oxidase (∆choD), as well as complimented strain (∆choD–choD) were used. We tested the impact of Mtb strains on the expression of TLR2-depended signaling proteins (mRNA level, cytosolic level and phosphorylation status). The cytokine and bactericidal response of THP-1 derived macrophages infected with Mtb strains in relation to TLR2 signaling pathway dependence was also determined. We found that during the 24-hours of infection process the wild-type and complemented Mtb significantly reduced the cytosolic level and phosphorylation status of IRAK-4 and TRAF-6 proteins in macrophages, that was not observed in the case of ΔchoD mutant. Decreasement of TLR2-dependent signaling proteins, induced by wild-type Mtb, was not dependent on the activity of proteasome. Blocking of TLR2 expression, before infection, effectively prevented the induced by wild-type strain reduction of cytosolic level and phosphorylation of IRAK-4. None of the strains affected the surface expression of TLR2. The mRNA level of IRAK-4 and TRAF-6 genes were significantly increased in macrophages 24 hours post-infection with either of tested strains. However, the impact of wild-type Mtb strain on both examined genes was significantly stronger than its ΔchoD mutant. We also found that wild-type strain stimulated macrophages to release high amount of immunosuppressive IL-10, accompanied by low amount of pro-inflammatory IL-8 and bactericidal nitric oxide in comparison to mutant lacking cholesterol oxidase. The influence of wild-type Mtb on this type of macrophages' response strongly dependent on fully active IRAK-1 and IRAK-4 signaling proteins. In conclusion, Mtb using cholesterol oxidase causes the over-activation of TLR2 signaling proteins leading to the reduction of their cytosolic level and activity resulting in the modulation of macrophages response to allow its intracellular survival. Supported by grant: 2014/15/B/NZ6/01565, National Science Center, Poland

Keywords: Mycobacterium tuberculosis, cholesterol oxidase, macrophages, TLR2-dependent signaling pathway

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1324 Cell Biomass and Lipid Productivities of Meyerella planktonica under Autotrophic and Heterotrophic Growth Conditions

Authors: Rory Anthony Hutagalung, Leonardus Widjaja

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Microalgae Meyerella planktonica is a potential biofuel source because it can grow in bulk in either autotrophic or heterotrophic condition. However, the quantitative growth of this algal type is still low as it tends to precipitates on the bottom. Beside, the lipid concentration is still low when grown in autotrophic condition. In contrast, heterotrophic condition can enhance the lipid concentration. The combination of autotrophic condition and agitation treatment was conducted to increase the density of the culture. On the other hand, a heterotrophic condition was set up to raise the lipid production. A two-stage experiment was applied to increase the density at the first step and to increase the lipid concentration in the next step. The autotrophic condition resulted higher density but lower lipid concentration compared to heterotrophic one. The agitation treatment produced higher density in both autotrophic and heterotrophic conditions. The two-stage experiment managed to enhance the density during the autotrophic stage and the lipid concentration during the heterotrophic stage. The highest yield was performed by using 0.4% v/v glycerol as a carbon source (2.9±0.016 x 106 cells w/w) attained 7 days after the heterotrophic stage began. The lipid concentration was stable starting from day 7.

Keywords: agitation, glycerol, heterotrophic, lipid productivity, Meyerella planktonica

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1323 Maize Farmers’ Perception of Sharp Practices among Agro-Input Dealers in Ibadan/Ibarapa Agricultural Zone, Oyo State

Authors: Ademola A. Ladele, Peace I. Aburime

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Fake and substandard agricultural inputs pose a serious stumbling block to farm productivity and subsequently improved livelihood. There is, therefore, a need to pave ways for sustainable agriculture and self-sufficiency in food production by proffering solutions to this challenge. Maize farmers' perception of sharp practices among agro-input dealers in Ibadan/Ibarapa agricultural zone in Oyo state was therefore investigated. A multi-stage random sampling technique was used to select registered maize farmers in the Ibadan/Ibarapa agricultural zone of the Oyo State Agricultural Development Programme (OYSADEP). A structured questionnaire was used to collect information on the perception of sharp practices and the effects of sharp practices. A total of seventy-five maize farmers were interviewed. A focus group discussion was organized to identify ways of curbing sharp practices to complement the survey. Data were analyzed using descriptive statistics, Chi-square, and Pearson Product Moment Correlation (PPMC). Forms of sharp practices indicated were sales of expired fertilizers, expired pesticides, expired herbicides, underweight fertilizers, adulterated fertilizers, adulterated herbicides, packs containing broken seeds, infested seeds, lack of truth in labeling/wrong labels, manipulation of measuring scales, and false declaration of hecterages covered by tractor operators. The majority had unfavorable perception of agro-input dealers on sharp practices. A significant relationship was observed between respondents’ level of education and their perception of sharp practices. There were no significant relationships between respondents’ sex, marital status and religion, and their perception of sharp practices. A significant correlation exists between the forms of sharp practices and the perceived effect on agricultural production. It is concluded that the perceived effect of sharp practices was critical and the endemic culture of sharp practices prevailed in agro-input in Ibadan/Ibarapa agricultural zone. A standard regulatory system that will certify and monitor the quality of inputs should be put in place.

Keywords: agricultural productivity, agro-input dealers, maize farmers, sharp practices

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1322 Extracellular Protein Secreted by Bacillus subtilis ATCC21332 in the Presence of Streptomycin Sulfate

Authors: M. N. Hanina, M. Hairul Shahril, I. Ismatul Nurul Asyikin, A. K. Abdul Jalil, M. R. Salina, M. R. Maryam, M. Rosfarizan

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The extracellular proteins secreted by bacteria may be increased in stressful surroundings, such as in the presence of antibiotics. It appears that many antibiotics, when used at low concentrations, have in common the ability to activate or repress gene transcription, which is distinct from their inhibitory effect. There have been comparatively few studies on the potential of antibiotics as a specific chemical signal that can trigger a variety of biological functions. Therefore, this study was carried out to determine the effect of Streptomycin Sulfate in regulating extracellular proteins secreted by Bacillus subtilis ATCC21332. Results of Microdilution assay showed that the Minimum Inhibition Concentration (MIC) of Streptomycin Sulfate on B. subtilis ATCC21332 was 2.5 mg/ml. The bacteria cells were then exposed to Streptomycin Sulfate at concentration of 0.01 MIC before being further incubated for 48h to 72 h. The extracellular proteins secreted were then isolated and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Proteins profile revealed that three additional bands with approximate sizes of 30 kDa, 22 kDa and 23 kDa were appeared for the treated bacteria with Streptomycin Sulfate. Thus, B. subtilis ATCC21332 in stressful condition with the presence of Streptomycin Sulfate at low concentration could induce the extracellular proteins secretion.

Keywords: Bacillus subtilis ATCC21332, streptomycin sulfate, extracellular proteins, antibiotics

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1321 Case Report: Rare Case of Endometrial Stromal Sarcoma with Omental Metastasis in a 19-Year Old Girl

Authors: Mukurdipi Ray, Seema Singh

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Extrauterine endometrial stromal sarcoma (ESS) is a rare entity and typified by delayed recurrence of primary ESS. Here, we present an unusual case of uterine ESS in a woman with a history of hysterectomy. A 19-year-old girl, underwent a hysterectomy and bilateral salpingo-oophorectomy for uterine ESS 12 months ago and now after remaining disease free for nine months ago she presented with ascites along with pelvic and peritoneal mass. Intraoperatively, the large omental mass was found, and optimal cytoreduction with total omentomy (supracolic and infracolic ) total peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC) was offered to the patient. Final histopathology report showed the involvement of only omentum by ESS cells. Immunohistochemistry (IHC) and receptor study were done and it was positive for CD-10 and desmin and negative for CK- 7. This case highlights the rarity of extrauterine ESS in the omentum with a known history of primary uterine ESS which was treated successfully with the above-mentioned procedure. Though active and long-term surveillance is recommended to monitor for late recurrences.

Keywords: endrometrial stromal sarcoma, complete cytoreduction, hyperthermic intra peritoneal chemotherapy, total omentectomy

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1320 Formal Innovations vs. Informal Innovations: The Case of the Mining Sector in Nigeria

Authors: Jegede Oluseye Oladayo

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The study mapped innovation activities in the formal and informal mining sector in Nigeria. Data were collected through primary and secondary sources. Primary data were collected through guided questionnaire administration, guided interviews and personal observation. A purposive sampling method was adopted to select firms that are micro, small and medium enterprises. The study covered 100 (50 in the formal sector and 50 in the informal sector) purposively selected companies in south-western Nigeria. Secondary data were collected from different published sources. Data were analysed using descriptive and inferential statistics. Of the four types of technological innovations sampled, organisational innovation was found to be highest both in the formal (100%) and informal (100%) sectors, followed by process innovation: 60% in the formal sector and 28% in the informal sector, marketing innovation and diffusion based innovation were implemented by 64% and 4% respectively in the formal sector. There were no R&D activities (intramural or extramural) in both sectors, however, innovation activities occur at moderate levels in the formal sector. This is characterised by acquisition of machinery, equipment, hardware (100%), software (56), training (82%) and acquisition of external knowledge (60%) in the formal sector. In the informal sector, innovation activities were characterised by acquisition of external knowledge (100%), training/learning by experience (100%) and acquisition of tools (68%). The impact of innovation on firm’s performance in the formal sector was expressed mainly as increased capacity of production (100%), reduced production cost per unit of labour (88%), compliance with governmental regulatory requirements (72%) and entry on new markets (60%). In the informal sector, the impact of innovation was mainly expressed in improved flexibility of production (70%) and machinery/energy efficiency (70%). The important technological driver of process innovation in the mining sector was acquisition of machinery which accounts for the prevalence of 100% both in the formal and informal sectors. Next to this is training and re-training of technical staff, 74% in both the formal and the informal sector. Other factors influencing organisational innovation are skill of workforce with a prevalence of 80% in both the formal and informal sector. The important technological drivers include educational background of the manager/head of technical department (54%) for organisational innovation and (50%) for process innovation in the formal sector. The study concluded that innovation competence of the firms was mostly organisational changes.

Keywords: innovation prevalence, innovation activities, innovation performance, innovation drivers

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1319 Correlation between Resistance to Non-Specific Inhibitor and Mammalian Pathogenicity of an Egg Adapted H9N2 Virus

Authors: Chung-Young Lee, Se-Hee Ahn, Jun-Gu Choi, Youn-Jeong Lee, Hyuk-Joon Kwon, Jae-Hong Kim

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A/chicken/Korea/01310/2001 (H9N2) (01310) was passaged through embryonated chicken eggs (ECEs) by 20 times (01310-E20), and it has been used for an inactivated oil emulsion vaccine in Korea. After sequential passages, 01310-E20 showed higher pathogenicity in ECEs and acquired multiple mutations including a potential N-glycosylation at position 133 (H3 numbering) in HA and 18aa-deletion in NA stalk. To evaluate the effect of these mutations on the mammalian pathogenicity and resistance to non-specific inhibitors, we generated four PR8-derived recombinant viruses with different combinations of HA and NA from 01310-E2 and 01310-E20 (rH2N2, rH2N20, rH20N2, and rH20N20). According to our results, recombinant viruses containing 01310 E20 HA showed higher growth property in MDCK cells and higher virulence on mice than those containing 01310 E2 HA regardless of NA. The hemagglutination activity of rH20N20 was less inhibited by egg white and mouse lung extract than that of other recombinant viruses. Thus, the increased pathogenicity of 01310-E20 may be related to both higher replication efficiency and resistance to non-specific inhibitors in mice.

Keywords: avian influenza virus, egg adaptation, H9N2, N-glycosylation, stalk deletion of neuraminidase

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1318 Interaction of Steinernema Glaseri, an Entomopathogenic Nematode with a Predatory Fungus Arthrobotrys Superba on Different Nutrient Media

Authors: Varsha Baweja

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Steinernema glaseri is known to be the most potent biocontrol agent against a number of insect pests of various orders and of diverse habitats under laboratory conditions. But in nature many micro pathogens may affect the efficacy of such entomopathogenic nematodes. Keeping this in view, the interaction of Steinernema glaseri with a predatory fungus Arthrobotrys superba was assessed on eight different nutrient media. The activity of A.superba was evaluated in terms of trap formation, conidiophore formation, and number of adhesive cells formed in the presence and absence of nematodes. The fungus failed to form any trap on any of the culture media in the absence of nematodes. However, in the presence of nematodes, the trap formation by the test fungus was increased but the number of conidiophores decreased with increase in dilution of Corn Meal Agar from 5% to 2%. Higher number of chlamydospores were observed in phenylalanine treated medium which indicates the inhibiting effect of phenylalanine on the growth of A. superba. Our results suggest that care should be taken during release of entomopathogenic nematodes in an agroecosystem for managing various insect pests in a more efficient manner.

Keywords: Entomopathogenic Nematode , Steinernema Glaseri, Predatory Fungus, Arthrobotrys Superba

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1317 Recent Volatility in Islamic Banking Sector of Bangladesh: Nexus Between Economy, Religion and Politics

Authors: Abdul Kader

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This paper attempts to investigate several contributory factors to recent volatility in the Islamic Banking sector of Bangladesh. In particular, the study explores corporate governance, credit management, credit regulations, inept board of directors, using religious sentiment as a means to deceive general people, and the degree of political interference as potential contributory factors. To find the correlation among different variables, semi-structured questionnaires were distributed among the clients, bank managers, some Banking scholars and ex-members of the board of directors of three Islamic Banks in Bangladesh. Later, ten interviews were collected from key informants to gain in-depth information about the present mismanagement of Islamic Banks in Bangladesh. After then, data were analyzed using statistical software and substantiated by secondary sources like newspapers, reports and investigative reports aired in screen media. The paper found a correlation between almost all contributory factors and recent unstable conditions in the Islamic banking sector. After performing regression analysis, this paper found a more significant relationship between some of the contributory factors with Banking volatility than others. For instance, credit management, inept board of directors, depriving customers of proving no profit in the name of business—no interest-- and political interference have a strong significant positive correlation with the present poor condition of Islamic Banking. This paper concludes that while internal management is important in recovering the losses, the government needs to ensure framing better policy for the Islamic Banking system, Central Bank needs to supervise and monitor all Islamic banks meticulously and loan receivers must go through the impartial evaluation and approved by the representatives of the Central Shariah Board. This paper also recommends that there is a need to strengthen the auditing system and improve regulatory oversight of the Islamic Banks in Bangladesh. Policy recommendations that this paper put forward could provide an outline for dealing with the existing challenging condition of Islamic Banks and these could be applied to similar problems in other countries where the Islamic Banking model exists.

Keywords: Islamic bank, volatility in banking sector, shariah law, credit management, political interference

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1316 Magnesium Nanoparticles for Photothermal Therapy

Authors: E. Locatelli, I. Monaco, R. C. Martin, Y. Li, R. Pini, M. Chiariello, M. Comes Franchini

Abstract:

Despite the many advantages of application of nanomaterials in the field of nanomedicine, increasing concerns have been expressed on their potential adverse effects on human health. There is urgency for novel green strategies toward novel materials with enhanced biocompatibility using safe reagents. Photothermal ablation therapy, which exploits localized heat increase of a few degrees to kill cancer cells, has appeared recently as a non-invasive and highly efficient therapy against various cancer types; anyway new agents able to generate hyperthermia when irradiated are needed and must have precise biocompatibility in order to avoid damage to healthy tissues and prevent toxicity. Recently, there has been increasing interest in magnesium as a biomaterial: it is the fourth most abundant cation in the human body, and it is essential for human metabolism. However magnesium nanoparticles (Mg NPs) have had limited diffusion due to the high reduction potential of magnesium cations, which makes NPs synthesis challenging. Herein, we report the synthesis of Mg NPs and their surface functionalization for the obtainment of a stable and biocompatible nanomaterial suitable for photothermal ablation therapy against cancer. We synthesized the Mg crystals by reducing MgCl2 with metallic lithium and exploiting naphthalene as an electron carrier: the lithium–naphthalene complex acts as the real reducing agent. Firstly, the nanocrystal particles were coated with the ligand 12-ethoxy ester dodecanehydroxamic acid, and then entrapped into water-dispersible polymeric micelles (PMs) made of the FDA-approved PLGA-b-PEG-COOH copolymer using the oil-in-water emulsion technique. Lately, we developed a more straightforward methodology by introducing chitosan, a highly biocompatible natural product, at the beginning of the process, simultaneously using lithium–naphthalene complex, thus having a one-pot procedure for the formation and surface modification of MgNPs. The obtained MgNPs were purified and fully characterized, showing diameters in the range of 50-300 nm. Notably, when coated with chitosan the particles remained stable as dry powder for more than 10 months. We proved the possibility of generating a temperature rise of a few to several degrees once MgNPs were illuminated using a 810 nm diode laser operating in continuous wave mode: the temperature rise resulted significant (0-15 °C) and concentration dependent. We then investigated potential cytotoxicity of the MgNPs: we used HN13 epithelial cells, derived from a head and neck squamous cell carcinoma and the hepa1-6 cell line, derived from hepatocellular carcinoma and very low toxicity was observed for both nanosystems. Finally, in vivo photothermal therapy was performed on xenograft hepa1-6 tumor bearing mice: the animals were treated with MgNPs coated with chitosan and showed no sign of suffering after the injection. After 12 hours the tumor was exposed to near-infrared laser light. The results clearly showed an extensive damage to tumor tissue after only 2 minutes of laser irradiation at 3Wcm-1, while no damage was reported when the tumor was treated with the laser and saline alone in control group. Despite the lower photothermal efficiency of Mg with respect to Au NPs, we consider MgNPs a promising, safe and green candidate for future clinical translations.

Keywords: chitosan, magnesium nanoparticles, nanomedicine, photothermal therapy

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1315 Effect of Oxidative Stress from Smoking on Erythrocyte Phosphatidylserine Externalization

Authors: Ratchaneewan Maneemaroj, Paveena Noisuwan, Chonlada Lakhonphon

Abstract:

The smoking is one of the major risk factors in Non-Communicable Disease. Free radicals from cigarette smoke can cause oxidative stress. The oxidative insults can lead to red blood cell (RBC) senescence and are involved in the clearance of red blood cells. The objective of the present study is to assess the association between smoke, oxidative stress evaluated with serum Malondialdehyde (MDA) level and phosphatidylserine (PS) externalization (biomarker of RBC senescence) evaluated with annexin V binding. A total of sixty-four male volunteers aged 25-60 years old were recruited in this study. MDA was measured by colorimetric method. Annexin V binding was detected by flow cytometry. Our results show that there was a significant increase in MDA levels in cigarette smokers as compared to non-smokers (p < 0.001). However, there was no significant different between annexin V binding (% gate) in cigarette smokers and non-smokers (p = 0.978). These results provide evidence of free radical from smoking is associated with oxidative damage to erythrocytes. However, our results suggest that PS externalization is unlikely to have a role in RBC senescence pathway of stressed erythrocytes from cigarette smoke. The other biomarker of RBC senescence should be determined on cigarette smoker erythrocytes.

Keywords: malondialdehyde, phosphatidylserine, RBC senescence, annexin V

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1314 Prevalence of Sarcocystosis in Slaughtered Sheep and Goats

Authors: Shivan N. Hussein, Ihsan K. Zangana

Abstract:

A total of 2358 sheep and 532 goats were examined for the presence of macrocystis of Sarcocystis. For microcysts, different muscle tissues were randomly taken from 118 sheep and 110 goats. Macrocystis were examined through naked eye inspection, while microcysts were examined microscopically by using histopathology, pepsin digestion, mincing & squeezing, and muscle squash method. Overall prevalence of macrocystis was 1.2% in sheep and 2.6% in goats. The intensity rate of the cysts was 4 cysts/ gram in sheep & 3 cysts/ gram in goats, respectively, while the overall prevalence of microcysts in sheep and goats was 96.5%. The infection rate in sheep was 96.6% and in goats was 96.4%. The total intensity rate of microcysts was 32.4 cysts/ field in sheep and 16.8 cysts/ field in goats, respectively. Histopathological examination found different shapes, size, wall thickness, and intensity rates of microcysts in muscle tissues of sheep & goats. The pathological reaction showed mild to moderate granulocytosis, and mononuclear cells infiltrated surrounding the microcysts with necrotizing and degeneration of myofibrils. The largest average size of spindle and round shaped cysts (290 ± 89.7 x 76.1 ± 10 µm and 88.8 ± 10.3 µm) in goats and (127.2 ± 18.9 x 53.3 ± 5.4 µm and 74.4 ± 7.5 µm) in sheep, was detected in the esophageal muscle. Statistically, there was a significant difference (p < 0.05) in the prevalence of macrocystis in sheep and goats, while no significant difference (p > 0.05) was observed in the prevalence of microcysts between both animal species.

Keywords: macrocystis, microcysts, intensity rate, measurement size

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1313 Antiprotozoal Activity of Peganum harmala against Babesiosis in Cattle

Authors: Muhammad Mustafa Jafar, Syed Ashar Mahfooz, Muhammad Ejaz Saleem, Muhammad Asif Raza, Asghar Abbas, Rao Zahid Abbas, Muhammad Kasib Khan, Hafiz Muhammad Ishaq

Abstract:

The Babesia gradually attained resistance against the synthetic medicines. To overcome the drug resistance, herbal therapy has gained more attention as compared to allopathic therapy. Peganumharmala (harmal) is a plant which has shown effective results against various protozoal diseases. Therefore, the present study was planned to monitor the efficacy of Peganumharmala (aqueous extract) against Babesiosis in cattle. For this purpose, a total of forty (n=40) infected animals were randomly divided into four equal groups (A, B, C, and D). Group A was treated with aqueous extract of Peganum harmala at 7.5 mg/kg, group B at 10 mg/kg and group C at 12.5 mg/kg of body weight. Group D served as a control group (normal). It was observed that there was a stabilization in hematological parameters (white and red blood cells, hemoglobin and Packed cell volume) in infected animals treated with Peganum harmala at different doses. Results of this study hence indicated that Peganum harmala extract at 12.5mg/kg BW is more effective against Babesiosis than lower doses.

Keywords: Babesiosis, cattle, control, Peganum harmala

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1312 The Overexpression of Horsegram MURLK Improves Regulation of Cell Death and Defense Responses to Microbial Pathogens

Authors: Shikha Masand, Sudesh Kumar Yadav

Abstract:

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

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

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1311 A QoE-driven Cross-layer Resource Allocation Scheme for High Traffic Service over Open Wireless Network Downlink

Authors: Liya Shan, Qing Liao, Qinyue Hu, Shantao Jiang, Tao Wang

Abstract:

In this paper, a Quality of Experience (QoE)-driven cross-layer resource allocation scheme for high traffic service over Open Wireless Network (OWN) downlink is proposed, and the related problem about the users in the whole cell including the users in overlap region of different cells has been solved.A method, in which assess models of the BestEffort service and the no-reference assess algorithm for video service are adopted, to calculate the Mean Opinion Score (MOS) value for high traffic service has been introduced. The cross-layer architecture considers the parameters in application layer, media access control layer and physical layer jointly. Based on this architecture and the MOS value, the Binary Constrained Particle Swarm Optimization (B_CPSO) algorithm is used to solve the cross-layer resource allocation problem. In addition,simulationresults show that the proposed scheme significantly outperforms other schemes in terms of maximizing average users’ MOS value for the whole system as well as maintaining fairness among users.

Keywords: high traffic service, cross-layer resource allocation, QoE, B_CPSO, OWN

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1310 Microarray Data Visualization and Preprocessing Using R and Bioconductor

Authors: Ruchi Yadav, Shivani Pandey, Prachi Srivastava

Abstract:

Microarrays provide a rich source of data on the molecular working of cells. Each microarray reports on the abundance of tens of thousands of mRNAs. Virtually every human disease is being studied using microarrays with the hope of finding the molecular mechanisms of disease. Bioinformatics analysis plays an important part of processing the information embedded in large-scale expression profiling studies and for laying the foundation for biological interpretation. A basic, yet challenging task in the analysis of microarray gene expression data is the identification of changes in gene expression that are associated with particular biological conditions. Careful statistical design and analysis are essential to improve the efficiency and reliability of microarray experiments throughout the data acquisition and analysis process. One of the most popular platforms for microarray analysis is Bioconductor, an open source and open development software project based on the R programming language. This paper describes specific procedures for conducting quality assessment, visualization and preprocessing of Affymetrix Gene Chip and also details the different bioconductor packages used to analyze affymetrix microarray data and describe the analysis and outcome of each plots.

Keywords: microarray analysis, R language, affymetrix visualization, bioconductor

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1309 Alternative Hypotheses on the Role of Oligodendrocytes in Neurocysticercosis: Comprehensive Review

Authors: Humberto Foyaca Sibat, Lourdes de Fátima Ibañez Valdés

Abstract:

Background Cysticercosis (Ct) is a preventable and eradicable zoonotic parasitic disease secondary to a cestode infection by the larva form of pig tapeworm Taenia solium (Ts), mainly seen in people living in developing countries. When the cysticercus is in the brain parenchymal, intraventricular system, subarachnoid space (SAS), cerebellum, brainstem, optic nerve, or spinal cord, then it has named neurocysticercosis (NCC), and the often-clinical manifestations are headache and epileptic seizures/epilepsy among other less frequent symptoms and signs. In this study, we look for a manuscript related to the role played by oligodendrocytes in the pathogenesis of NCC. We review this issue and formulate some hypotheses regarding its role and the role played in the pathogenesis of calcified NCC and epileptic seizures, and secondary epilepsy. Method: We searched the medical literature comprehensively, looking for published medical subject heading (MeSH) terms like "neurocysticercosis", "pathogenesis of neurocysticercosis", "comorbidity in NCC"; OR "oligodendrocytes"; OR "oligodendrocyte precursor cells(OPC/NG2)"; OR "epileptic seizures(ES)/Epilepsy(Ep)/NCC" OR "oligodendrocytes(OLG)/ES/Ep”; OR "calcified NCC/OLG"; OR “OLG Ca2+.” Results: All selected manuscripts were peer-reviewed, and we did not find publications related to OLG/NCC.

Keywords: oligodendrocytes, neurocysticercosis, oligodendrocytes, oligodendrocyte precursor cell, KG2, calcified neurocysticercosis, cellular calcium influx.

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1308 Structural and Optical Properties of Ce3+ Doped YPO4: Nanophosphors Synthesis by Sol Gel Method

Authors: B. Kahouadji, L. Guerbous, L. Lamiri, A. Mendoud

Abstract:

Recently, nanomaterials are developed in the form of nano-films, nano-crystals and nano-pores. Lanthanide phosphates as a material find extensive application as laser, ceramic, sensor, phosphor, and also in optoelectronics, medical and biological labels, solar cells and light sources. Among the different kinds of rare-earth orthophosphates, yttrium orthophosphate has been shown to be an efficient host lattice for rare earth activator ions, which have become a research focus because of their important role in the field of light display systems, lasers, and optoelectronic devices. It is in this context that the 4fn- « 4fn-1 5d transitions of rare earth in insulating materials, lying in the UV and VUV, are the aim of large number of studies .Though there has been a few reports on Eu3+, Nd3+, Pr3+,Er3+, Ce3+, Tm3+ doped YPO4. The 4fn- « 4fn-1 5d transitions of the rare earth dependent to the host-matrix, several matrices ions were used to study these transitions, in this work we are suggesting to study on a very specific class of inorganic material that are orthophosphate doped with rare earth ions. This study focused on the effect of Ce3+ concentration on the structural and optical properties of Ce3+ doped YPO4 yttrium orthophosphate with powder form prepared by the Sol Gel method.

Keywords: YPO4, Ce3+, 4fn- <->4fn-1 5d transitions, scintillator

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1307 Epicatechin Metabolites and Its Effect on ROS Production in Bovine Aortic Endothelial Cells

Authors: Nasiruddin Khan

Abstract:

The action of (-)-epicatechin, a cocoa (Theobroma cacao) flavanol that modulates redox/oxidative stress are contributed mainly to their antioxidant properties. The present study investigates the concentration and time dependent effect of (-)-epicatechin metabolites 3MeEc, 4MeEc, and 4SulEc on the production of ROS on BAEC using L-012, Lucigenin as chemiluminescence dye and XO/HX system. Our result demonstrates that 3MeEc shows significant (P <0.05) lowering effect of ROS production in BAEC with increasing concentration of metabolite while L-012 was used as chemiluminescence dye but not in the case of Lucigenin. In XO/HX system, using L-012 as chemiluminescence dye, 3MeEc and 4MeEc showed significant lowering effect on ROS production with increasing concentration from 100-500nM as compared to the positive control (SOD). When Lucigenin was used as chemiluminescence dye, 3MeEc exerted significant lowering effect with increasing concentration when compared to the positive control (SOD) whereas 4MeEc showed significant lowering effect in ROS production from 250 nM on as compared to positive control. For 4SulEc, a significant lowering effect of ROS production was only observed at 100 and 250 nM. Overall, although each metabolite shows considerable effect, 3MeEc exhibited more pronounced effect on decreasing the production of ROS as compared to other two metabolites.

Keywords: epicatechin metabolites, HO-1, Nrf2, ROS

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1306 Broad Protection against Avian Influenza Virus by Using a Modified Vaccinia Ankara Virus Expressing a Mosaic Hemagglutinin

Authors: Attapon Kamlangdee, Brock Kingstad-Bakke, Tavis K. Anderson, Tony L. Goldberg, Jorge E. Osorio

Abstract:

A critical failure in our preparedness for an influenza pandemic is the lack of a universal vaccine. Influenza virus strains diverge by 1 to 2% per year, and commercially available vaccines often do not elicit protection from one year to the next, necessitating frequent formulation changes. This represents a major challenge to the development of a cross-protective vaccine that can protect against circulating viral antigenic diversity. We have constructed a recombinant modified vaccinia virus Ankara (MVA) that expresses an H5N1 mosaic hemagglutinin (H5M) (MVA-H5M). This mosaic was generated in silico using 2,145 field-sourced H5N1 isolates. A single dose of MVA-H5M provided 100% protection in mice against clade 0, 1, and 2 avian influenza viruses and also protected against seasonal H1N1 virus (A/Puerto Rico/8/34). It also provided short-term (10 days) and long-term (6 months) protection post vaccination. Both neutralizing antibodies and antigen-specific CD4+and CD8+ T cells were still detected at 5 months post vaccination, suggesting that MVA-H5M provides long-lasting immunity.

Keywords: modified vaccinia Ankara, MVA, H5N1, hemagglutinin, influenza vaccine

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1305 Changes in Global DNA Methylation and DNA Damage in Two Tumor Cell Lines Treated with Silver and Gold Nanoparticles

Authors: Marcin Kruszewski, Barbara Sochanowicz, Sylwia Męczyńska-Wielgosz, Maria Wojewódzka, Lucyna Kapka-Skrzypczak

Abstract:

Metallic NPs are widely used in a number of applications in industry, science and medicine. Among metallic NPs foreseen to be widely used in medicine are gold nanoparticles (AuNPs) due to their low toxicity, and silver NPs (AgNPs) due to their strong antimicrobial activity. In this study, we compared an effect of AgNPs and gold NPs (AuNPs) on the formation of DNA damage and global DNA methylation and in A2780 and 4T1 cell lines, widely used models of human ovarian carcinoma and murine mammary carcinoma, respectively. The cells were treated with AgNPs coated with citrate (AgNPs(cit) or PEG (AgNPs(PEG), or AuNPs. A global DNA methylation was investigated with ELISA, whereas the formation of DNA damage was investigated by a comet +/- FPG. AgNPs decreased global DNA methylation and increased the formation of DNA lesions in both cell lines. The effect was dependent on the type of NPs used, it's coating, and cell line used. In conclusion, the epigenetic and genotoxic effects of NPs strongly depends on NP nature and cellular context. Epigenetic changes observed upon the action of AgNPs may play a crucial role in NPs-induced changes in protein expression.

Keywords: DNA damage, gold nanoparticles, methylation, silver nanoparticles

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