Search results for: solid basal cell carcinoma
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6011

Search results for: solid basal cell carcinoma

1241 Ergosterol Biosynthesis: Non-Conventional Method for Improving Process

Authors: Madalina Postaru, Alexandra Tucaliuc, Dan Cascaval, Anca Irina Galaction

Abstract:

Ergosterol (ergosta-5,7,22-trien-3β-ol) is the precursor of vitamin D2 (ergocalciferol), known as provitamin D2 as it is converted under UV radiation to this vitamin. The natural sources of ergosterol are mainly the yeasts (Saccharomyces sp., Candida sp.), but it can be also found in fungus (Claviceps sp.) or plants (orchids). As ergosterol is mainly accumulated in yeast cell membranes, especially in free form in the plasma-membrane, and the chemical synthesis of ergosterol does not represent an efficient method for its production, this study aimed to analyze the influence of aeration efficiency on ergosterol production by S. cerevisiae in batch and fed-batch fermentations, by considering different levels of mixing intensity, aeration rate, and n-dodecane concentration. Our previous studies on ergosterol production by S. cerevisiae in batch and fed-batch fermentation systems indicated that the addition of n-dodecane led to the increase of almost 50% of this sterol concentration, the highest productivity being reached for the fed-batch process. The experiments were carried out in a laboratory stirred bioreactor, provided with computer-controlled and recorded parameters. In batch fermentation system, the study indicated that the oxygen mass transfer coefficient, kLa, is amplified for about 3 times by increasing the volumetric concentration of n-dodecane from 0 to 15%. Moreover, the increase of dissolved oxygen concentration by adding n-dodecane leads to the diminution for 3.5 times of the produced alcohol amount. In fed-batch fermentation process, the positive influence of hydrocarbon on oxygen transfer rate is amplified mainly at its higher concentration level, as the result of the increased yeasts cells amount. Thus, by varying n-dodecane concentration from 0 to 15% vol., the kLa value increase becomes more important than for the batch fermentation, being of 4 times

Keywords: ergosterol, yeast fermentation, n-dodecane, oxygen-vector

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1240 Mathematical Modelling and AI-Based Degradation Analysis of the Second-Life Lithium-Ion Battery Packs for Stationary Applications

Authors: Farhad Salek, Shahaboddin Resalati

Abstract:

The production of electric vehicles (EVs) featuring lithium-ion battery technology has substantially escalated over the past decade, demonstrating a steady and persistent upward trajectory. The imminent retirement of electric vehicle (EV) batteries after approximately eight years underscores the critical need for their redirection towards recycling, a task complicated by the current inadequacy of recycling infrastructures globally. A potential solution for such concerns involves extending the operational lifespan of electric vehicle (EV) batteries through their utilization in stationary energy storage systems during secondary applications. Such adoptions, however, require addressing the safety concerns associated with batteries’ knee points and thermal runaways. This paper develops an accurate mathematical model representative of the second-life battery packs from a cell-to-pack scale using an equivalent circuit model (ECM) methodology. Neural network algorithms are employed to forecast the degradation parameters based on the EV batteries' aging history to develop a degradation model. The degradation model is integrated with the ECM to reflect the impacts of the cycle aging mechanism on battery parameters during operation. The developed model is tested under real-life load profiles to evaluate the life span of the batteries in various operating conditions. The methodology and the algorithms introduced in this paper can be considered the basis for Battery Management System (BMS) design and techno-economic analysis of such technologies.

Keywords: second life battery, electric vehicles, degradation, neural network

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1239 Chitosan Hydrogel Containing Nitric Oxide Donors with Potent Antibacterial Effect

Authors: Milena Trevisan Pelegrino, Bruna De Araujo Lima, Mônica H. M. Do Nascimento, Christiane B. Lombello, Marcelo Brocchi, Amedea B. Seabra

Abstract:

Nitric oxide (NO) is a small molecule involved in a wide range of physiological and pathophysiological processes, including vasodilatation, control of inflammatory pain, wound healing, and antibacterial activities. As NO is a free radical, the design of drugs that generates therapeutic amounts of NO in controlled spatial and time manners is still a challenge. In this study, the NO donor S-nitrosoglutathione (GSNO) was incorporated into the thermoresponsive Pluronic F-127 (PL) - chitosan (CS) hydrogel, in an easy and economically feasible methodology. CS is a polysaccharide with known antimicrobial and biocompatibility properties. Scanning electron microscopy, rheology and differential scanning calorimetry techniques were used for hydrogel characterization. The results demonstrated that the hydrogel has a smooth surface, thermoresponsive behavior, and good mechanical stability. The kinetics of NO release and GSNO diffusion from GSNO-containing PL/CS hydrogel demonstrated a sustained NO/GSNO release, in concentrations suitable for biomedical applications, at physiological and skin temperatures. The GSNO-PL/CS hydrogel demonstrated a concentration-dependent toxicity to Vero cells, and antimicrobial activity to Pseudomonas aeruginosa (minimum inhibitory concentration and minimum bactericidal concentration values of 0.5 µg·mL-1 of hydrogel, which correspondents to 1 mmol·L-1 of GSNO). Interesting, the concentration range in which the NO-releasing hydrogel demonstrated antibacterial effect was not found toxic to Vero mammalian cell. Thus, GSNO-PL/CS hydrogel is suitable biomaterial for topical NO delivery applications.

Keywords: antimicrobial, chitosan, biocompatibility, S-nitrosothiols

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1238 Comparison of Acetylcholinesterase Reactivators Cytotoxicity with Their Structure

Authors: Lubica Muckova, Petr Jost, Jaroslav Pejchal, Daniel Jun

Abstract:

The development of acetylcholinesterase reactivators, i.e. antidotes against organophosphorus poisoning, is an important goal of defence research. The aim of this study was to compare cytotoxicity and chemical structure of 5 currently available (pralidoxime, trimedoxime, obidoxime, methoxime, and asoxime) and 4 newly developed compounds (K027, K074, K075, and K203). In oximes, there could be at least four important structural factors affecting their toxicity, including the number of oxime groups in the molecule, the position of oxime group(s) on pyridinium ring, the length of carbon linker, and the substitution by oxygen or insertion of the double bond into the connection chain. The cytotoxicity of tested substances was measured using colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay (MTT assay) in SH-SY5Y cell line. Toxicity was expressed as toxicological index IC₅₀. The tested compounds showed different cytotoxicity ranging from 1.5 to 27 mM. K027 was the least, and methoxime was the most toxic reactivator. The lowest toxicity was found in a monopyridinium reactivator and bispyridinium reactivators with simple 3C carbon linker. Shortening of connection chain length to 1C, incorporation of oxygen moiety into 3C compounds, elongation of carbon linker to 4C and insertion of a double bond into 4C substances increase AChE reactivators' cytotoxicity. Acknowledgements: This work was supported by a long-term organization development plan Medical Aspects of Weapons of Mass Destruction of the Faculty of Military Health Sciences, University of Defence.

Keywords: acetylcholinesterase, cytotoxicity, organophosphorus poisoning, reactivators of acetylcholinesterase

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1237 The Effects of Some Organic Amendments on Sediment Yield, Splash Loss, and Runoff of Soils of Selected Parent Materials in Southeastern Nigeria

Authors: Leonard Chimaobi Agim, Charles Arinzechukwu Igwe, Emmanuel Uzoma Onweremadu, Gabreil Osuji

Abstract:

Soil erosion has been linked to stream sedimentation, ecosystem degradation, and loss of soil nutrients. A study was conducted to evaluate the effect of some organic amendment on sediment yield, splash loss, and runoff of soils of selected parent materials in southeastern Nigeria. A total of 20 locations, five from each of four parent materials namely: Asu River Group (ARG), Bende Ameki Group (BAG), Coastal Plain Sand (CPS) and Falsebedded Sandstone (FBS) were used for the study. Collected soil samples were analyzed with standard methods for the initial soil properties. Rainfall simulation at an intensity of 190 mm hr-1was conducted for 30 minutes on the soil samples at both the initial stage and after amendment to obtain erosion parameters. The influence of parent material on sediment yield, splash loss and runoff based on rainfall simulation was tested for using one way analyses of variance, while the influence of organic material and their combinations were a factorially fitted in a randomized complete block design. The organic amendments include; goat dropping (GD), poultry dropping (PD), municipal solid waste (MSW) and their combinations (COA) applied at four rates of 0, 10, 20 and 30 t ha-1 respectively. Data were analyzed using analyses of variance suitable for a factorial experiment. Significant means were separated using LSD at 5 % probability levels. Result showed significant (p ≤ 0.05) lower values of sediment yield, splash loss and runoff following amendment. For instance, organic amendment reduced sediment yield under wet and dry runs by 12.91 % and 26.16% in Ishiagu, 40.76% and 45.67%, in Bende, 16.17% and 50% in Obinze and 22.80% and 42.35% in Umulolo respectively. Goat dropping and combination of amendment gave the best results in reducing sediment yield.

Keywords: organic amendment, parent material, rainfall simulation, soil erosion

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1236 Synthesis and in vitro Characterization of a Gel-Derived SiO2-CaO-P2O5-SrO-Li2O Bioactive Glass

Authors: Mehrnaz Aminitabar, Moghan Amirhosseinian, Morteza Elsa

Abstract:

Bioactive glasses (BGs) are a group of surface-reactive biomaterials used in clinical applications as implants or filler materials in the human body to repair and replace diseased or damaged bone. Sol-gel technique was employed to prepare a SiO2-CaO-P2O5 glass with nominal composition of 58S BG with the addition of Sr and Li modifiers which imparts special properties to the BG. The effect of simultaneous addition of Sr and Li on bioactivity and biocompatibility, proliferation, alkaline phosphatase (ALP) activity of osteoblast cell line MC3T3-E1 and antibacterial property against methicillin-resistant Staphylococcus aureus (MRSA) bacteria were examined. BGs were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy before and after soaking the samples in the simulated body fluid (SBF) for different time intervals to characterize the formation of hydroxyapatite (HA) formed on the surface of BGs. Structural characterization indicated that the simultaneous presence of 5% Sr and 5% Li in 58S-BG composition not only did not retard HA formation because of opposite effect of Sr and Li of the dissolution of BG in the SBF but also, stimulated the differentiation and proliferation of MC3T3-E1s. Moreover, the presence of Sr and Li on dissolution of the ions resulted in an increase in the mean number of DAPI-labeled nuclei which was in good agreement with live/dead assay. The result of antibacterial tests revealed that Sr and Li-substituted 58S BG exhibited a potential antibacterial effect against MRSA bacteria. Because of optimal proliferation and ALP activity of MC3T3-E1cells, proper bioactivity and high antibacterial potential against MRSA, BG-5/5 is suggested as a multifunctional candidate for bone tissue engineering.

Keywords: antibacterial activity, bioactive glass, sol-gel, strontium

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1235 A Comparative Analysis of the Performances of Four Different In-Ground Lagoons Anaerobic Digesters in the Treatment of Palm Oil Mill Effluent (POME)

Authors: Mohd Amran, Chan Yi Jing, Chong Chien Hwa

Abstract:

Production of biogas from POME requires anaerobic digestion (AD), thus, anaerobic digester performance in biogas plants is crucial. As POME from different sources have varying characteristics due to different process flows in mills, there is no ideal treatment parameters for POME. Hence, different treatment plants alter different parameters in anaerobic digestion to achieve desired biogas production levels and to meet POME waste discharge limits. The objective of this study is to evaluate the performance of mesophilic anaerobic digestion in four different biogas plants in Malaysia. Aspects of POME pre-treatment efficiency, analysis of treated POME and AD’s bottom sludge characteristics, including several parameters like chemical oxygen demand (COD), biological oxygen demand (BOD), total solid (TS) removal in the effluent, pH and temperature changes, total biogas produced, the composition of biogas including methane (CH₄), carbon dioxide (CO₂), hydrogen sulfide (H₂S) and oxygen (O₂) were investigated. The effect of organic loading rate (OLR) and hydraulic retention time (HRT) on anaerobic digester performance is also evaluated. In pre-treatment, it is observed that BGP B has the lowest average outlet temperature of 40.41°C. All BGP shows a high-temperature fluctuation (36 to 49 0C) and good pH readings (minimum 6.7), leaving the pre-treatment facility before entering the AD.COD removal of POME is considered good, with an average of 78% and maximum removal of 85%. BGP C has the lowest average COD and TS content in treated POME, 13,313 mg/L, and 12,048 mg/L, respectively. However, it is observed that the treated POME leaving all ADs, still contains high-quality organic substances (COD between 12,000 to 19,000 mg/L) that might be able to digest further to produce more biogas. The biogas produced in all four BGPs varies due to different COD loads. BGP B has the highest amount of biogas produced, 378,874.7 Nm³/month, while BGP D has the lowest biogas production of 272,378.5 Nm³/month. Furthermore, the composition of biogas produced in all plants is well within literature values (CH4 between 55 to 65% and CO₂ between 32 to 36%).

Keywords: palm oil mill effluent, in-ground lagoon anaerobic digester, anaerobic digestion, biogas

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1234 Removal of Nickel and Vanadium from Crude Oil by Using Solvent Extraction and Electrochemical Process

Authors: Aliya Kurbanova, Nurlan Akhmetov, Abilmansur Yeshmuratov, Yerzhigit Sugurbekov, Ramiz Zulkharnay, Gulzat Demeuova, Murat Baisariyev, Gulnar Sugurbekova

Abstract:

Last decades crude oils have tended to become more challenge to process due to increasing amounts of sour and heavy crude oils. Some crude oils contain high vanadium and nickel content, for example Pavlodar LLP crude oil, which contains more than 23.09 g/t nickel and 58.59 g/t vanadium. In this study, we used two types of metal removing methods such as solvent extraction and electrochemical. The present research is conducted for comparative analysis of the deasphalting with organic solvents (cyclohexane, carbon tetrachloride, chloroform) and electrochemical method. Applying the cyclic voltametric analysis (CVA) and Inductively coupled plasma mass spectrometry (ICP MS), these mentioned types of metal extraction methods were compared in this paper. Maximum efficiency of deasphalting, with cyclohexane as the solvent, in Soxhlet extractor was 66.4% for nickel and 51.2% for vanadium content from crude oil. Percentage of Ni extraction reached maximum of approximately 55% by using the electrochemical method in electrolysis cell, which was developed for this research and consists of three sections: oil and protonating agent (EtOH) solution between two conducting membranes which divides it from two capsules of 10% sulfuric acid and two graphite electrodes which cover all three parts in electrical circuit. Ions of metals pass through membranes and remain in acid solutions. The best result was obtained in 60 minutes with ethanol to oil ratio 25% to 75% respectively, current fits into the range from 0.3A to 0.4A, voltage changed from 12.8V to 17.3V.

Keywords: demetallization, deasphalting, electrochemical removal, heavy metals, petroleum engineering, solvent extraction

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1233 Investigating the Effect of the Psychoactive Substances Act 2016 on the Incidence of Adverse Medical Events in Her Majesty’s Prison (HMP) Leeds

Authors: Hayley Boal, Chloe Bromley, John Fairfield

Abstract:

Novel Psychoactive Substances (NPS) are synthetic compounds designed to reproduce effects of illicit drugs. Cheap, potent, and readily available on UK highstreets from so-called ‘head shops’, in recent years their use has surged and with it have emerged side effects including seizures, aggression, palpitations, coma, and death. Rapid development of new substances has vastly outpaced pre-existing drug legislation but the Psychoactive Substances Act 2016 rendered all but tobacco, alcohol, and amyl nitrates, illegal. Drug use has long been rife within prisons, but the absence of a reliable screening tool alongside the availability of NPS makes them ideal for prison use. Here we examine the occurrence of NPS-related adverse side effects within HMP Leeds, comparing May-September of 2015 and 2017 using daily reports distributed amongst prison staff summarising medical and behavioural incidents of the previous day. There was a statistically-significant rise of over 200% in the use of NPS between 2015 and 2017: 0.562 and 1.149 incidents per day respectively. In 2017, 38.46% incidents required ambulances, fallen from 51.02% in 2015. Although the most common descriptions in both years were ‘seizure’ and ‘unresponsive’, by 2017 ‘inhalation by staff’ had emerged. Patterns of NPS consumption mirrored the prison regime, peaking when cell doors opened, and prisoners could socialise. Despite limited data, the Psychoactive Substances Act has clearly been an insufficient deterrent to the prison population; more must be done to understand and address substance misuse in prison. NPS remains a significant risk to prisoners’ health and wellbeing.

Keywords: legislation, novel psychoactive substances, prison, spice

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1232 Evaluation of the Diagnostic Potential of IL-2 after Specific Antigen Stimulation with PE35 (Rv3872) and PPE68 (Rv3873) for the Discrimination of Active and Latent Tuberculosis

Authors: Shima Mahmoudi, Babak Pourakbari, Setareh Mamishi, Mostafa Teymuri, Majid Marjani

Abstract:

Although cytokine analysis has greatly contributed to the understanding of tuberculosis (TB) pathogenesis, data on cytokine profiles that might distinguish progression from latency of TB infection are scarce. Since PE/PPE proteins are known to induce strong humoral and cellular immune responses, the aim of this study was to evaluate the diagnostic potential of interleukin-2 (IL-2) as biomarker after specific antigen stimulation with PE35 and PPE68 for the discrimination of active and latent tuberculosis infection (LTBI). The production of IL-2 was measured in the antigen-stimulated whole-blood supernatants following stimulation with recombinant PE35 and PPE68. All the patients with active TB and LTBI had positive QuantiFERON-TB Gold in Tube test. The level of IL-2 following stimulation with recombinant PE35 and PPE68 were significantly higher in LTBI group than in patients with active TB infection or control group. The discrimination performance (assessed by the area under ROC curve) for IL-2 following stimulation with recombinant PE35 and PPE68 between LTBI and patients with active TB were 0.837 (95%CI: 0.72-0.97) and 0.75 (95%CI: 0.63-0.89), respectively. Applying the 12.4 pg/mL cut-off for IL-2 induced by PE35 in the present study population resulted in sensitivity of 78%, specificity of 78%, PPV of 78% and NPV of 100%. In addition, a sensitivity of 81%, specificity of 70%, PPV of 67% and 87% of NPV was reported based on the 4.4 pg/mL cut-off for IL-2 induced by PPE68. In conclusion, peptides of the antigen PE35 and PPE68, absent from commonly used BCG strains, stimulated strong IL-2- positive T cell responses in patients with LTBI. This study confirms IL-2 induced by PE35 and PPE68 as a sensitive and specific biomarker and highlights IL-2 as new promising adjunct markers for discriminating of LTBI and Active TB infection.

Keywords: IL-2, PE35, PPE68, tuberculosis

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1231 Fexofenadine Hydrochloride Orodispersisble Tablets: Formulation and in vitro/in vivo Evaluation in Healthy Human Volunteers

Authors: Soad Ali Yehia, Mohamed Shafik El-Ridi, Mina Ibrahim Tadros, Nolwa Gamal El-Sherif

Abstract:

Fexofenadine hydrochloride (FXD) is a slightly soluble, bitter-tasting, drug having an oral bioavailability of 35%. The maximum plasma concentration is reached 2.6 hours (Tmax) post-dose. The current work aimed to develop taste-masked FXD orodispersible tablets (ODTs) to increase extent of drug absorption and reduce Tmax. Taste masking was achieved via solid dispersion (SD) with chitosan (CS) or sodium alginate (ALG). FT-IR, DSC and XRD were performed to identify physicochemical interactions and FXD crystallinity. Taste-masked FXD-ODTs were developed via addition of superdisintegrants (crosscarmelose sodium or sodium starch glycolate, 5% and 10%, w/w) or sublimable agents (camphor, menthol or thymol; 10% and 20%, w/w) to FXD-SDs. ODTs were evaluated for weight variation, drug-content, friability, wetting time, disintegration time and drug release. Camphor-based (20%, w/w) FXD-ODT (F12) was optimized (F23) by incorporation of a more hydrophilic lubricant, sodium stearyl fumarate (Pruv®). The topography of the latter formula was examined via scanning electron microscopy (SEM). The in vivo estimation of FXD pharmacokinetics, relative to Allegra® tablets, was evaluated in healthy human volunteers. Based on the gustatory sensation test in healthy volunteers, FXD:CS (1:1) and FXD:ALG (1:0.5) SDs were selected. Taste-masked FXD-ODTs had appropriate physicochemical properties and showed short wetting and disintegration times. Drug release profiles of F23 and phenylalanine-containing Allegra® ODT were similar (f2 = 96) showing a complete release in two minutes. SEM micrographs revealed pores following camphor sublimation. Compared to Allegra® tablets, pharmacokinetic studies in healthy volunteers proved F23 ability to increase extent of FXD absorption (14%) and reduce Tmax to 1.83 h.

Keywords: fexofenadine hydrochloride, taste masking, chitosan, orodispersible

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1230 Conjugated Linoleic Acid (CLA) Health Benefits and Sources

Authors: Hilal Ahmad Punoo

Abstract:

Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of octadecadienoic acid with two conjugated double bonds. Of more than a dozen isomers of CLA found naturally in dairy and meat products from ruminants, c-9, t-11 and t-10, c-12 are the two isomers with known physiological importance, including anticarcinogenic, antidiabetic, antilipogenic, and antiatherosclerotic effects. Conjugated linoleic acids (CLA) may influence the onset and severity of several chronic diseases, including various cancers, atherosclerosis, obesity, bone density loss, and diabetes. These findings are of special interest to the agriculture community, because dietary sources of CLA are almost exclusively beef and dairy products. Thus, a better understanding of the specific isomers and mechanisms responsible for these positive effects of CLA on human health would be both prudent and economically beneficial. To date, research related to the advantages of CLA consumption on human health has been conducted using experimental laboratory animals and cell culture systems. These data consistently show that relatively low levels of CLA can influence risk of cancer. Further, very recent investigations suggest that the predominate CLA isoform (cis-9, trans-11 CLA or rumenic acid) found in beef and milk fat possesses anticarcinogenic effects but does not alter body composition; the trans-10, cis-12 CLA has been shown to inhibit lipogenesis. Clearly, further work, especially using human subjects, will be required to characterize the potential benefits of CLA consumption on human health. Moreover, we suggest that foods naturally containing high amounts of CLA (e.g., beef and dairy products) be considered as meeting the definition of functional foods.

Keywords: conjugated linoleic acid, potential health benefits, fats, animals, humans

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1229 Improving Biodegradation Behavior of Fabricated WE43 Magnesium Alloy by High-Temperature Oxidation

Authors: Jinge Liu, Shuyuan Min, Bingchuan Liu, Bangzhao Yin, Bo Peng, Peng Wen, Yun Tian

Abstract:

WE43 magnesium alloy can be additively manufactured via laser powder bed fusion (LPBF) for biodegradable applications, but the as-built WE43 exhibits an excessively rapid corrosion rate. High-temperature oxidation (HTO) was performed on the as-built WE43 to improve its biodegradation behavior. A sandwich structure including an oxide layer at the surface, a transition layer in the middle, and the matrix was generated influenced by the oxidation reaction and diffusion of RE atoms when heated at 525 ℃for 8 hours. The oxide layer consisted of Y₂O₃ and Nd₂O₃ oxides with a thickness of 2-3 μm. The transition layer is composed of α-Mg and Y₂O₃ with a thickness of 60-70 μm, while Mg24RE5 could be observed except α-Mg and Y₂O₃. The oxide layer and transition layer appeared to have an effective passivation effect. The as-built WE43 lost 40% weight after the in vitro immersion test for three days and finally broke into debris after seven days of immersion. The high-temperature oxidation samples kept the structural integrity and lost only 6.88 % weight after 28-day immersion. The corrosion rate of HTO samples was significantly controlled, which improved the biocompatibility of the as-built WE43 at the same time. The samples after HTO had better osteogenic capability according to ALP activity. Moreover, as built WE43 performed unqualified in cell adhesion and hemolytic test due to its excessively rapid corrosion rate. While as for HTO samples, cells adhered well, and the hemolysis ratio was only 1.59%.

Keywords: laser powder bed fusion, biodegradable metal, high temperature oxidation, biodegradation behavior, WE43

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1228 Effect of Al Addition on Microstructure and Properties of NbTiZrCrAl Refractory High Entropy Alloys

Authors: Xiping Guo, Fanglin Ge, Ping Guan

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Refractory high entropy alloys are alternative materials expected to be employed at high temperatures. The comprehensive changes of microstructure and properties of NbTiZrCrAl refractory high entropy alloys are systematically studied by adjusting Al content. Five kinds of button alloy ingots with different contents of Al in NbTiZrCrAlX (X=0, 0.2, 0.5, 0.75, 1.0) were prepared by vacuum non-consumable arc melting technology. The microstructure analysis results show that the five alloys are composed of BCC solid solution phase rich in Nb and Ti and Laves phase rich in Cr, Zr, and Al. The addition of Al changes the structure from hypoeutectic to hypereutectic, increases the proportion of Laves phase, and changes the structure from cubic C15 to hexagonal C14. The hardness and fracture toughness of the five alloys were tested at room temperature, and the compressive mechanical properties were tested at 1000℃. The results showed that the addition of Al increased the proportion of Laves phase and decreased the proportion of the BCC phase, thus increasing the hardness and decreasing the fracture toughness at room temperature. However, at 1000℃, the strength of 0.5Al and 0.75Al alloys whose composition is close to the eutectic point is the best, which indicates that the eutectic structure is of great significance for the improvement of high temperature strength of NbTiZrCrAl refractory high entropy alloys. The five alloys were oxidized for 1 h and 20 h in static air at 1000℃. The results show that only the oxide film of 0Al alloy falls off after oxidizing for 1 h at 1000℃. After 20h, the oxide film of all the alloys fell off, but the oxide film of alloys containing Al was more dense and complete. By producing protective oxide Al₂O₃, inhibiting the preferential oxidation of Zr, promoting the preferential oxidation of Ti, and combination of Cr₂O₃ and Nb₂O₅ to form CrNbO₄, Al significantly improves the high temperature oxidation resistance of NbTiZrCrAl refractory high entropy alloys.

Keywords: NbTiZrCrAl, refractory high entropy alloy, al content, microstructural evolution, room temperature mechanical properties, high temperature compressive strength, oxidation resistance

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1227 Eco-Friendly Control of Bacterial Speck on Solanum lycopersicum by Azadirachta indica Extract

Authors: Navodit Goel, Prabir K. Paul

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Tomato (Solanum lycopersicum) is attacked by Pseudomonas syringae pv. tomato causing speck lesions on the leaves leading to severe economic casualty. In the present study, aqueous fruit extracts of Azadirachta indica (neem) were sprayed on a single node of tomato plants grown under controlled contamination-free conditions. The treatment of plants was performed with neem fruit extract either alone or along with the pathogen. The parameters of observation were activities of polyphenol oxidase (PPO) and lysozyme, and isoform analysis of PPO; both at the treated leaves as well as untreated leaves away from the site of extract application. Polyphenol oxidase initiates phenylpropanoid pathway resulting in the synthesis of quinines from cytoplasmic phenols and production of reactive oxygen species toxic to broad spectrum microbes. Lysozyme is responsible for the breakdown of bacterial cell wall. The results indicate the upregulation of PPO and lysozyme activities in both the treated and untreated leaves along with de novo expression of newer PPO isoenzymes (which were absent in control samples). The appearance of additional PPO isoenzymes in bioelicitor-treated plants indicates that either the isoenzymes were expressed after bioelicitor application or the already expressed but inactive isoenzymes were activated by it. Lysozyme activity was significantly increased in the plants when treated with the bioelicitor or the pathogen alone. However, no new isoenzymes of lysozyme were expressed upon application of the extract. Induction of resistance by neem fruit extract could be a potent weapon in eco-friendly plant protection strategies.

Keywords: Azadirachta indica, lysozyme, polyphenol oxidase, Solanum lycopersicum

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1226 Gis-Based Water Pollution Assesment of Buriganga River, Bangladesh

Authors: Nur-E-Jannat Tinu

Abstract:

Water is absolutely vital not only for the survival of human beings but also for plants, animals, and all other living organisms. Water bodies, such as lakes, rivers, ponds, and estuaries, are the source of water supply in domestic, industrial, agriculture, and aquaculture purposes. The Buriganga River flows through the south and west of Dhaka city. The water quality of this river has become a matter of concern due to anthropogenic intervention of vital pollutants such as industrial effluents, urban sewage, and solid wastes in this area. Buriganga River is at risk to contamination from untreated municipal wastes, industrial discharges, runoff from organic and inorganic fertilizers, pesticides, insecticides, and oil emission around the river. The residential and commercial establishments along the river discharge wastewater either directly into the river or through drains and canals into the river. However, several regulatory measures and policies have been enforced by the Government to protect the river Buriganga from pollution, in most cases to no affect. Water quality assessment reveals that the water is also not appropriate for irrigation purposes. The physical parameters (pH, TDS, EC, Temperature, DO, COD, BOD) indicated that the water is too poor to be useable for agricultural, drinking, or other purposes. Chemical concentrations showed significant seasonal variations with high-level concentrations during the monsoon season, presumably due to extreme seasonal surface runoff. A comparative study of Electrical Conductivity (EC) and Total Dissolved Solids (TDS) indicated a considerable increase over the last five years A change in trend was observed from 2020 June-July, probably due to monsoon and post-monsoon. EC values decreased from 775 to 665 mmho/cm during this period. DO increased significantly from the mid-post-monsoon months to the early monsoon period. The pH value of river water is strongly alkaline, ranging between 6.5 and 7.79. This indicates that ecological organic compounds cause the water to become alkaline after the monsoon and monsoon seasons. As the water pollution level is very high, an effective remediation and pollution control plan should be considered.

Keywords: precipitation, spatial distribution, effluent, remediation

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1225 Antihyperglycemic Potential of Chrysin and Diosmin alone or in Combination against Streptozotocin-Induced Hyperglycemia in Rats: Anti-Inflammatory and Antioxidant Mechanisms

Authors: Sally A. El Awdan, Gehad A. Abdel Jaleel, Dalia O Saleh, Manal Badawi

Abstract:

Background: Diabetes is a metabolic disease that affects a wide range of people worldwide and results in serious complications. Streptozotocin (STZ) causes selective cytotoxicity in the pancreatic β-cell, and it has been extensively used to induce diabetes mellitus in rats. The present study investigated the effects of diosmin and chrysin alone or in combination with each other on glucose level and on liver in STZ diabetic rats. Methods: In this study, rats were divided into six experimental groups (normal, untreated STZ-diabetic (60 mg/kg B.W., IP), treated STZ-diabetic with glycazide (10 mg/kg B.W, oral), treated STZ-diabetic with diosmin (100 mg/kg B. W., oral), treated STZ-diabetic with chrysin (80 mg/kg B.W., oral), treated STZ-diabetic with diosmin (50 mg/kg B.W, oral) + chrysin (40 mg/kg B.W., oral). After 2 weeks blood samples were withdrawn and glucose was measured. Animals were anaesthetized with an intraperitoneal injection of sodium pentobarbital (60 mg/kg), and sacrificed for dissecting liver. Results: Throughout the experimental period, all treatments significantly (P<0.05) lowered serum glucose, AST, ALT, triglyceride, cholesterol, IL-6, TNF-α and IL-1β. Moreover, the treated diabetic rats showed higher levels of reduced glutathione (P<0.05) in the liver compared to the diabetic control rats and inhibited diabetes-induced elevation in the levels of malondialdehyde in liver. The results of this study clearly demonstrated that diosmin and chrysin possess several treatment-oriented properties, including the control of hyperglycemia, antioxidant effects and anti-inflammatory effects. Conclusion: Considering these observations, it appears that diosmin and chrysin may be a useful supplement to delay the developmentof diabetes and its complications.

Keywords: diabetes, streptozocin, chrysin, rat, diosmin, cytokines

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1224 Encapsulation of Probiotic Bacteria in Complex Coacervates

Authors: L. A. Bosnea, T. Moschakis, C. Biliaderis

Abstract:

Two probiotic strains of Lactobacillus paracasei subsp. paracasei (E6) and Lactobacillus paraplantarum (B1), isolated from traditional Greek dairy products, were microencapsulated by complex coacervation using whey protein isolate (WPI, 3% w/v) and gum arabic (GA, 3% w/v) solutions mixed at different polymer ratio (1:1, 2:1 and 4:1). The effect of total biopolymer concentration on cell viability was assessed using WPI and GA solutions of 1, 3 and 6% w/v at a constant ratio of 2:1. Also, several parameters were examined for optimization of the microcapsule formation, such as inoculum concentration and the effect of ionic strength. The viability of the bacterial cells during heat treatment and under simulated gut conditions was also evaluated. Among the different WPI/GA weight ratios tested (1:1, 2:1, and 4:1), the highest survival rate was observed for the coacervate structures made with the ratio of 2:1. The protection efficiency at low pH values is influenced by both concentration and the ratio of the added biopolymers. Moreover, the inoculum concentration seems to affect the efficiency of microcapsules to entrap the bacterial cells since an optimum level was noted at less than 8 log cfu/ml. Generally, entrapment of lactobacilli in the complex coacervate structure enhanced the viability of the microorganisms when exposed to a low pH environment (pH 2.0). Both encapsulated strains retained high viability in simulated gastric juice (>73%), especially in comparison with non-encapsulated (free) cells (<19%). The encapsulated lactobacilli also exhibited enhanced viability after 10–30 min of heat treatment (65oC) as well as at different NaCl concentrations (pH 4.0). Overall, the results of this study suggest that complex coacervation with WPI/GA has a potential to deliver live probiotics in low pH food systems and fermented dairy products; the complexes can dissolve at pH 7.0 (gut environment), releasing the microbial cells.

Keywords: probiotic, complex coacervation, whey, encapsulation

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1223 Determinants of Cessation of Exclusive Breastfeeding in Ankesha Guagusa Woreda, Awi Zone, Northwest Ethiopia: A Cross-Sectional Study

Authors: Tebikew Yeneabat, Tefera Belachew, Muluneh Haile

Abstract:

Background: Exclusive breast-feeding (EBF) is the practice of feeding only breast milk (including expressed breast milk) during the first six months and no other liquids and solid foods except medications. The time to cessation of exclusive breast-feeding, however, is different in different countries depending on different factors. Studies showed the risk of diarrhea morbidity and mortality is higher among none exclusive breast-feeding infants, common during starting other foods. However, there is no study that evaluated the time to cessation of exclusive breast-feeding in the study area. The aim of this study was to show time to cessation of EBF and its predictors among mothers of index infants less than twelve months old. Methods: We conducted a community-based cross-sectional study from February 13 to March 3, 2012 using both quantitative and qualitative methods. This study included a total of 592 mothers of index infant using multi-stage sampling method. Data were collected by using interviewer administered structured questionnaire. Bivariate and multivariate Cox regression analyses were performed. Results: Cessation of exclusive breast-feeding occurred in 392 (69.63%) cases. Among these, 224 (57.1%) happened before six months, while 145 (37.0%) and 23 (5.9%) occurred at six months and after six months of age of the index infant respectively. The median time for infants to stay on exclusive breast-feeding was 6.36 months in rural and 5.13 months in urban, and this difference was statistically significant on a Log rank (Cox-mantel) test. Maternal and paternal occupation, place of residence, postnatal counseling on exclusive breast-feeding, mode of delivery, and birth order of the index infant were significant predictors of cessation of exclusive breast-feeding. Conclusion: Providing postnatal care counseling on EBF, routine follow-up and support of those mothers having infants stressing for working mothers can bring about implementation of national strategy on infant and young child feeding.

Keywords: exclusive breastfeeding, cessation, median duration, Ankesha Guagusa Woreda

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1222 The Role of Micro-Ribonucleic Acid-182 and Micro-Ribonucleic Acid-214 in Cisplatin Resistance of Triple-Negative Breast Cancer Cells

Authors: Bahadir Batar, Elif Serdal, Berna Erdal, Hasan Ogul

Abstract:

Micro-ribonucleic acids (miRNAs) are small short non-coding ribonucleic acid molecules about 22 nucleotides long. miRNAs play a key role in response to chemotherapeutic agents. WW domain-containing oxidoreductase (WWOX) gene encodes a tumor suppressor protein. Loss or reduction of Wwox protein is observed in many breast cancer cases. WWOX protein deficiency is increased in triple-negative breast cancer (TNBC). TNBC is a heterogeneous, highly aggressive, and difficult to treat tumor type. WWOX loss contributes to resistance to cisplatin therapy in patients with TNBC. Here, the aim of the study was to investigate the potential role of miRNAs in cisplatin therapy resistance of WWOX-deficient TNBC cells. This was a cell culture study. miRNA expression profiling was analyzed by LightCycler 480 system. miRNA Set Enrichment Analysis tool was used to integrate experimental data with literature-based biological knowledge to infer a new hypothesis. Increased miR-182 and decreased miR-214 were significantly correlated with cisplatin resistance in WWOX-deficient TNBC cells. miR-182 and miR-214 may involve in cisplatin resistance of WWOX-deficient TNBC cells by deregulating the DNA repair, apoptosis, or protein kinase B signaling pathways. These data highlight the mechanism by which WWOX regulates cisplatin resistance of TNBC and the potential use of WWOX as a predictor biomarker for cisplatin resistance.

Keywords: cisplatin, microRNA, triple-negative breast cancer, WWOX

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1221 Anticancer Activity of Calyx of Diospyros kaki Thunb. through Downregulation of Cyclin D1 Protein Level in Human Colorectal Cancer Cells

Authors: Jin Boo Jeong

Abstract:

In this study, we elucidated anti-cancer activity and potential molecular mechanism of DKC against human colorectal cancer cells. DKC-E70 suppressed the proliferation of human colorectal cancer cell lines such as HCT116, SW480, LoVo and HT-29. Although DKC-E70 decreased cyclin D1 expression in protein and mRNA level, decreased level of cyclin D1 protein by DKC-E70 occurred at the earlier time than that of cyclin D1 mRNA, which indicates that DKC-E70-mediated downregulation of cyclin D1 protein may be a consequence of the induction of degradation and transcriptional inhibition of cyclin D1. In cyclin D1 degradation, we found that cyclin D1 downregulation by DKC-E70 was attenuated in presence of MG132. In addition, DKC-E70 phosphorylated threonine-286 (T286) of cyclin D1 and T286A abolished cyclin D1 downregulation by DKC-E70. We also observed that DKC-E70-mediated T286 phosphorylation and subsequent cyclin D1 degradation was blocked in presence of the inhibitors of ERK1/2, p38 or GSK3β. In cyclin D1 transcriptional inhibition, DKC-E70 inhibited the expression of β-catenin and TCF4, and β–catenin/TCF-dependent luciferase activity. Our results suggest that DKC-E70 may downregulate cyclin D1 as one of the potential anti-cancer targets through cyclin D1 degradation by T286 phosphorylation dependent on ERK1/2, p38 or GSK3β, and cyclin D1 transcriptional inhibition through Wnt signaling. From these findings, DKC-E70 has potential to be a candidate for the development of chemoprevention or therapeutic agents for human colorectal cancer. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A3B03931713).

Keywords: anticancer, calyx of persimmon, cyclin D1, Diospyros kaki Thunb., human colorectal cancer

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1220 Experimental Correlation for Erythrocyte Aggregation Rate in Population Balance Modeling

Authors: Erfan Niazi, Marianne Fenech

Abstract:

Red Blood Cells (RBCs) or erythrocytes tend to form chain-like aggregates under low shear rate called rouleaux. This is a reversible process and rouleaux disaggregate in high shear rates. Therefore, RBCs aggregation occurs in the microcirculation where low shear rates are present but does not occur under normal physiological conditions in large arteries. Numerical modeling of RBCs interactions is fundamental in analytical models of a blood flow in microcirculation. Population Balance Modeling (PBM) is particularly useful for studying problems where particles agglomerate and break in a two phase flow systems to find flow characteristics. In this method, the elementary particles lose their individual identity due to continuous destructions and recreations by break-up and agglomeration. The aim of this study is to find RBCs aggregation in a dynamic situation. Simplified PBM was used previously to find the aggregation rate on a static observation of the RBCs aggregation in a drop of blood under the microscope. To find aggregation rate in a dynamic situation we propose an experimental set up testing RBCs sedimentation. In this test, RBCs interact and aggregate to form rouleaux. In this configuration, disaggregation can be neglected due to low shear stress. A high-speed camera is used to acquire video-microscopic pictures of the process. The sizes of the aggregates and velocity of sedimentation are extracted using an image processing techniques. Based on the data collection from 5 healthy human blood samples, the aggregation rate was estimated as 2.7x103(±0.3 x103) 1/s.

Keywords: red blood cell, rouleaux, microfluidics, image processing, population balance modeling

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1219 Anaerobic Co-Digestion of Sewage Sludge and Bagasse for Biogas Recovery

Authors: Raouf Ahmed Mohamed Hassan

Abstract:

In Egypt, the excess sewage sludge from wastewater Treatment Plants (WWTPs) is rapidly increasing due to the continuous increase of population, urban planning and industrial developments. Also, cane bagasses constitute an important component of Urban Solid Waste (USW), especially at the south of Egypt, which are difficult to degrade under normal composting conditions. These wastes need to be environmentally managed to reduce the negative impacts of its application or disposal. In term of biogas recovery, the anaerobic digestion of sewage sludge or bagasse separately is inefficient, due to the presence of nutrients and minerals. Also, the Carbone-Nitrogen Ratio (C/N) play an important role, sewage sludge has a ratio varies from 6-16, where cane bagasse has a ratio around 150, whereas the suggested optimum C/N ratio for anaerobic digestion is in the range of 20 to 30. The anaerobic co-digestion is presented as a successful methodology that combines several biodegradable organic substrates able to decrease the amount of output wastes by biodegradation, sharing processing facilities, reducing operating costs, while enabling recovery of biogas. This paper presents the study of co-digestion of sewage sludge from wastewater treatment plants as a type of organic wastes and bagasse as agriculture wastes. Laboratory-scale mesophilic and thermophilic digesters were operated with varied hydraulic retention times. Different percentage of sludge and bagasse are investigated based on the total solids (TS). Before digestion, the bagasse was subjected to grinding pretreatment and soaked in distilled water (water pretreatment). The effect of operating parameters (mixing, temperature) is investigated in order to optimize the process in the biogas production. The yield and the composition of biogas from the different experiments were evaluated and the cumulative curves were estimated. The conducted tests did show that there is a good potential to using the co-digestion of wastewater sludge and bagasse for biogas production.

Keywords: co-digestion, sewage sludge, bagasse, mixing, mesophilic, thermophilic

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1218 Avoiding Gas Hydrate Problems in Qatar Oil and Gas Industry: Environmentally Friendly Solvents for Gas Hydrate Inhibition

Authors: Nabila Mohamed, Santiago Aparicio, Bahman Tohidi, Mert Atilhan

Abstract:

Qatar's one of the biggest problem in processing its natural resource, which is natural gas, is the often occurring blockage in the pipelines caused due to uncontrolled gas hydrate formation in the pipelines. Several millions of dollars are being spent at the process site to dehydrate the blockage safely by using chemical inhibitors. We aim to establish national database, which addresses the physical conditions that promotes Qatari natural gas to form gas hydrates in the pipelines. Moreover, we aim to design and test novel hydrate inhibitors that are suitable for Qatari natural gas and its processing facilities. From these perspectives we are aiming to provide more effective and sustainable reservoir utilization and processing of Qatari natural gas. In this work, we present the initial findings of a QNRF funded project, which deals with the natural gas hydrate formation characteristics of Qatari type gas in both experimental (PVTx) and computational (molecular simulations) methods. We present the data from the two fully automated apparatus: a gas hydrate autoclave and a rocking cell. Hydrate equilibrium curves including growth/dissociation conditions for multi-component systems for several gas mixtures that represent Qatari type natural gas with and without the presence of well known kinetic and thermodynamic hydrate inhibitors. Ionic liquids were designed and used for testing their inhibition performance and their DFT and molecular modeling simulation results were also obtained and compared with the experimental results. Results showed significant performance of ionic liquids with up to 0.5 % in volume with up to 2 to 4 0C inhibition at high pressures.

Keywords: gas hydrates, natural gas, ionic liquids, inhibition, thermodynamic inhibitors, kinetic inhibitors

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1217 Complex Management of Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

Authors: Abdullah A. Al Qurashi, Hattan A. Hassani, Bader K. Alaslap

Abstract:

Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVD/C) is an uncommon, inheritable cardiac disorder characterized by the progressive substitution of cardiac myocytes by fibro-fatty tissues. This pathologic substitution predisposes patients to ventricular arrhythmias and right ventricular failure. The underlying genetic defect predominantly involves genes encoding for desmosome proteins, particularly plakophilin-2 (PKP2). These aberrations lead to impaired cell adhesion, heightening the susceptibility to fibrofatty scarring under conditions of mechanical stress. Primarily, ARVD/C affects the right ventricle, but it can also compromise the left ventricle, potentially leading to biventricular heart failure. Clinical presentations can vary, spanning from asymptomatic individuals to those experiencing palpitations, syncopal episodes, and, in severe instances, sudden cardiac death. The establishment of a diagnostic criterion specifically tailored for ARVD/C significantly aids in its accurate diagnosis. Nevertheless, the task of early diagnosis is complicated by the disease's frequently asymptomatic initial stages, and the overall rarity of ARVD/C cases reported globally. In some cases, as exemplified by the adult female patient in this report, the disease may advance to terminal stages, rendering therapies like Ventricular Tachycardia (VT) ablation ineffective. This case underlines the necessity for increased awareness and understanding of ARVD/C to aid in its early detection and management. Through such efforts, we aim to decrease morbidity and mortality associated with this challenging cardiac disorder.

Keywords: arrhythmogenic right ventricular dysplasia, cardiac disease, interventional cardiology, cardiac electrophysiology

Procedia PDF Downloads 41
1216 Effect of Sintering Time and Porosity on Microstructure, Mechanical and Corrosion Properties of Ti6Al15Mo Alloy for Implant Applications

Authors: Jyotsna Gupta, S. Ghosh, S. Aravindan

Abstract:

The requirement of artificial prostheses (such as hip and knee joints) has increased with time. Many researchers are working to develop new implants with improved properties such as excellent biocompatibility with no tissue reactions, corrosion resistance in body fluid, high yield strength and low elastic modulus. Further, the morphological properties of the artificial implants should also match with that of the human bone so that cell adhesion, proliferation and transportation of the minerals and nutrition through body fluid can be obtained. Present study attempts to make porous Ti6Al15Mo alloys through powder metallurgy route using space holder technique. The alloy consists of 6wt% of Al which was taken as α phase stabilizer and 15wt% Mo was taken as β phase stabilizer with theoretical density 4.708. Ammonium hydrogen carbonate is used as a space holder in order to generate the porosity. The porosity of these fabricated porous alloys was controlled by adding the 0, 50, 70 vol.% of the space holder content. Three phases were found in the microstructure: α, α_2 and β phase of titanium. Kirkendall pores are observed to be decreased with increase of holding time during sintering and parallelly compressive strength and elastic modulus value increased slightly. Compressive strength and elastic modulus of porous Ti-6Al-15Mo alloy (1.17 g/cm3 density) is found to be suitable for cancellous bone. Released ions from Ti-6Al-15Mo alloy are far below from the permissible limits in human body.

Keywords: bone implant, powder metallurgy, sintering time, Ti-6Al-15Mo

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1215 Level of IGF-I and IGFBP-3 in Gingival Crevicular Fluid and Plasma in Patients with Aggressive Periodontitis

Authors: Youjeong Hwang

Abstract:

Purpose: Insulin-like growth factor-I (IGF-I) promotes B-cell development, immunoglobulin formation, and interleukin-6 (IL-6) production, then regulate the immune response and inflammation. As IGF-I and their receptor also exist in the periodontal tissue, they may affect the immune response caused by periodontal pathogens in aggressive periodontitis (AgP) patients. The function of IGF is regulated by IGF binding proteins (IGFBPs), and IGFBP-3 is known to most abundant in plasma. The aim of the present study was to assess the concentration of IGF-I and IGFBP-3 in plasma and gingival crevicular fluid (GCF) in AgP patients and to find out their association. Methods: Nine patients with AgP (test group) and nine healthy subjects (control group) were included in this study. None of the subjects had a history of systemic disease, smoking or steroids medication. GCF samples were collected by microcapillary pipettes and plasma samples were obtained by venipuncture. Probing pocket depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were recorded. Samples were assayed for IGF-I and IGFBP-3 levels using ELISA. Results: Mean IGF-I level in GCF was higher in the test group than control. Mean IGF-I level in plasma and IGFBP-3 level in GCF and plasma in control group were higher than that of the test group. However, there was no statistical significance (p > 0.05). The mean level of IGF-I and IGFBP-3 in GCF was lower than those in plasma. Mean IGF-I level in plasma showed a negative correlation with PD and CAL (p < 0.05) in both groups. The levels of IGF-I and IGFBP-3 in GCF seemed to be negatively correlated with BOP in the test group (p < 0.05). Conclusions: The difference in the level of IGF-I and IGFBP-3 between AgP and healthy subjects was not significant. Further studies that explain the mechanism of the protective role of IGF-I with more samples are needed.

Keywords: aggressive periodontitis, pathogenesis, insulin-like growth factor, insulin-like growth factor binding protein

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1214 Comparing Pathogen Inhibition Effect of Different Preparations of Probiotic L. reuteri Strains

Authors: Tejinder Pal Singh, Ravinder Kumar Malik, Gurpreet Kaur

Abstract:

Adhesion is key factor for colonization of the gastrointestinal tract and the ability of probiotic strains to inhibit pathogens. Therefore, the adhesion ability is considered as a suitable biomarker for the selection of potential probiotic. In the present study, eight probiotic Lactobacillus reuteri strains were evaluated as viable, LiCl treated or heat-killed forms and compared with probiotic reference strains (L. reuteri ATCC55730). All strains investigated were able to adhere to Caco-2 cells. All probiotic L. reuteri strains tested were able to inhibit and displace (P < 0.05) the adhesion of Escherichia coli ATCC25922, Salmonella typhi NCDC113, Listeria monocytogenes ATCC53135 and Enterococcus faecalis NCDC115. The probiotic strain L. reuteri LR6 showed the strongest adhesion and pathogen inhibition ability among the eight L. reuteri strains tested. In addition, the abilities to inhibit and to displace adhered pathogens depended on both the probiotic and the pathogen strains tested suggesting the involvement of various mechanisms. The adhesion and antagonistic potential of the probiotic strains were significantly decreased upon exposure to 5M LiCl, showing that surface molecules, proteinaceous in nature, are involved. The heat-killed forms of the probiotic L. reuteri strains also inhibited the attachment of selected pathogens to Caco-2 cells. In conclusion, in vitro assays showed that L. reuteri strains, as viable or heat-killed forms, are adherent to Caco-2 cell line model and are highly antagonistic to selected pathogens in which surface molecules, proteinaceous molecules in particular, plays an important role.

Keywords: probiotics, Lactobacillus reuteri, adhesion, Caco-2 cells

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1213 Community Crèche Is a Measure to Prevent Child Injuries: Its Challenges and Measures for Improvement

Authors: Rabbya Ashrafi, Mohammad Tarikul Islam , Al-Amin Bhuiyan, Aminur Rahman

Abstract:

Injury is the leading killer of children in Bangladesh. Anchal (community crèche) is an effective intervention to prevent injuries among children under 5. Through the SoLiD project, 1,600 Anchals are in place in three sub-districts in Bangladesh. The objectives of the Anchal are to provide supervision and early childhood development stimulations (ECD) to the children. A locally trained caregiver supervises 20-25 children, 9 to 59 months old, from 9 a.m. to 1 p.m., six days a week. Although it was found effective, during its implementation phase several challenges were noticed. To identify challenges and means to overcome those to improve the Anchal activities. In-depth interviews were conducted with Anchal caregivers, their supervisors, and trainers. Focus group discussions were conducted with the mothers of the Anchal children. The study was conducted in the Manohardi sub-district in November 2015. Decay of knowledge and skills after 2-3 months of training, lack of formal certification and inappropriate selection of women as Anchal caregivers, and enrollment of small children (less than 12 months) were the important challenges. The reluctance of parents to send children to the Anchal at the proper time, failure to engage children in various ECD activities, ineffective conduction of parents and community leaders meeting by the Anchal caregivers, insufficient accommodation, and poor supply of logistics for children were also the important challenges. The suggestion for improvement was to recruit caregivers as per standard criteria, provide them refreshers training at three months intervals, train them on effective conduction of parents and community leaders meetings, provide a formal certificate, and ensure regular supply of logistics. The identified challenges are needed to be addressed by utilizing the suggestions obtained from the IDIs and FGDs to make the Anchal intervention more effective in preventing childhood injuries.

Keywords: comunity crech, earlychildhood development, measures for improvement, childhood injury

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1212 Chitosan Coated Liposome Incorporated Cyanobacterial Pigment for Nasal Administration in the Brain Stroke

Authors: Kyou Hee Shim, Hwa Sung Shin

Abstract:

When a thrombolysis agent is administered to treat ischemic stroke, excessive reactive oxygen species are generated due to a sudden provision of oxygen and occurs secondary damage cell necrosis. Thus, it is necessary to administrate adjuvant as well as thrombolysis agent to protect and reduce damaged tissue. As cerebral blood vessels have specific structure called blood-brain barrier (BBB), it is not easy to transfer substances from blood to tissue. Therefore, development of a drug carrier is required to increase drug delivery efficiency to brain tissue. In this study, cyanobacterial pigment from the blue-green algae known for having neuroprotective effect as well as antioxidant effect was nasally administrated for bypassing BBB. In order to deliver cyanobacterial pigment efficiently, the nano-sized liposome was used as a carrier. Liposomes were coated with a positive charge of chitosan since negative residues are present at the nasal mucosa the first gateway of nasal administration. Characteristics of liposome including morphology, size and zeta potential were analyzed by transmission electron microscope (TEM) and zeta analyzer. As a result of cytotoxic test, the liposomes were not harmful. Also, being administered a drug to the ischemic stroke animal model, we could confirm that the pharmacological effect of the pigment delivered by chitosan coated liposome was enhanced compared to that of non-coated liposome. Consequently, chitosan coated liposome could be considered as an optimized drug delivery system for the treatment of acute ischemic stroke.

Keywords: ischemic stroke, cyanobacterial pigment, liposome, chitosan, nasal administration

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