Search results for: metabolism and excretion–toxicity

Authors: Venkatesan Annadurai, Kannan Ethirajalu, Anu Roshini Ramakrishnan

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Copper oxide (CuO) and zinc oxide (ZnO) based coaxial (CuO-ZnO nanorods) heterojunction has been the interest of various research communities for solar cells, light emitting diodes (LEDs) and photodetectors applications. Copper oxide (CuO) is a p-type material with the band gap of 1.5 eV and it is considered to be an attractive absorber material in solar cells applications due to its high absorption coefficient and long minority carrier diffusion length. Similarly, n-type ZnO nanorods possess many attractive advantages over thin films such as, the light trapping ability and photosensitivity owing to the presence of oxygen related hole-traps at the surface. Moreover, the abundant availability, non-toxicity, and inexpensiveness of these materials make them suitable for potentially cheap, large area, and stable photovoltaic applications. However, the efficiency of the CuO-ZnO nanorods heterojunction based devices is greatly affected by interface defects which generally lead to the poor performance. In spite of having much potential, not much work has been carried out to understand the interface quality and transport mechanism involved across the CuO-ZnO nanorods heterojunction. Therefore, a detailed investigation of CuO-ZnO heterojunction is needed to understand the interface which affects its photovoltaic performance. Herein, we have fabricated the CuO-ZnO nanorods based heterojunction by simple hydrothermal and electrodeposition technique and investigated its interface quality by carrying out temperature (300 –10 K) dependent current-voltage (I-V) measurements under dark and illumination of visible light. Activation energies extracted from the temperature dependent I-V characteristics reveals that recombination and tunneling mechanism across the interfacial barrier plays a significant role in the current flow.

Keywords: heterojunction, electrical transport, nanorods, solar cells

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Authors: Sadaf Kalhori

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Introduction: Doxorubicin (DOX)-induced cardiotoxicity is widely known as the most severe complication of anthracycline-based chemotherapy in patients with cancer. It is unknown whether Deferiprone (DFP), could reduce the severity of DOX-induced cardiotoxicity by inhibiting free radical reactions. Thus, this study was performed to assess the protective effect of Deferiprone on DOX-induced cardiotoxicity in a rat model. Methods: The rats were divided into five groups. Group one was a control group. Group 2 was DOX (2 mg/kg/day, every other day for 12 days), and Group three to five which receiving DOX as in group 2 and DFP 75,100 and 150 mg/kg/day, for 19 days, respectively. DFP was starting 5 days prior to the first DOX injection and two days after the last DOX injection throughout the study. Electrocardiographic and hemodynamic studies, along with histopathological examination, were conducted. In addition, serum sample was taken and total cholesterol, Malone dialdehyde, triglyceride, albumin, AST, ALT, total protein, lactate dehydrogenase, total anti-oxidant and creatine kinase were assessed. Result: Our results showed the normal structure of endocardial, myocardial and pericardial in the control group. Pathologic data such as edema, hyperemia, bleeding, endocarditis, myocarditis and pericarditis, hyaline degeneration, cardiomyocyte necrosis, myofilament degeneration and nuclear chromatin changes were assessed in all groups. In the DOX group, all pathologic data was seen with mean grade of 2±1.25. In the DFP group with a dose of 75 and 100 mg, the mean grade was 1.41± 0.31 and 1±.23, respectively. In DFP group with a dose of 150, the pathologic data showed a milder change in comparison with other groups with e mean grade of 0.45 ±0.19. Most pathologic data in DFP groups showed significant changes in comparison with the DOX group (p < 0.001). Discussion: The results also showed that DFP treatment significantly improved DOX-induced heart damage, structural changes in the myocardium, and ventricular function. Our data confirm that DFP is protective against cardiovascular-related disorders induced by DOX. Clinical studies are needed to be involved to examine these findings in humans.

Keywords: cardiomyopathy, deferiprone, doxorubicin, rat

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Authors: Bushra

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This paper explores the historical significance, ecological benefits, and contemporary applications of natural dyes in textile dyeing, aiming to provide a comprehensive overview of their potential to contribute to a sustainable fashion industry while minimizing ecological footprints. This research explores the potential of natural dyes as a sustainable alternative to synthetic dyes in the textile industry, examining their historical context, sources, and environmental benefits. Natural dyes come from plants, animals, and minerals, including roots, leaves, bark, fruits, flowers, insects, and metal salts, used as mordants to fix dyes to fabrics. Natural dyeing involves extraction, mordanting, and dyeing techniques. Optimizing these processes can enhance the performance of natural dyes, making them viable for contemporary textile applications based on experimental research. Natural dyes offer eco-friendly benefits like biodegradability, non-toxicity, and resource renewables, reducing pollution, promoting biodiversity, and reducing reliance on petrochemicals. Natural dyes offer benefits but face challenges in color consistency, scalability, and performance, requiring industrial production to meet modern consumer standards for durability and colorfastness. Contemporary initiatives in the textile industry include fashion brands like Eileen Fisher and Patagonia incorporating natural dyes, artisans like India Flint's Botanical Alchemy promoting traditional dyeing techniques, and research projects like the European Union's Horizon 2020 program. Natural dyes offer a sustainable textile industry solution, reducing environmental impact and promoting harmony with nature. Research and innovation are paving the way for widespread adoption, transforming textile dyeing.

Keywords: historical significance, textile industry, natural dyes, sustainability

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Authors: Nahid Eskandari, Marjan Ghagozolo, Ehsan Almasi

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Introduction: Silymarin, as a polyphenolic flavonoid derived from milk thistle (Silybum marianum), is known to have antioxidant, immunomodulatory, antiproliferative, antifibrotic, and antiviral effects. The goal of this study was to determine immunosuppressive effect of Silymarin on proliferation and apoptosis of human T cells in comparison with Rapamycin and FK506. Methods: Peripheral Blood Mononuclear Cells (PBMCs) from healthy individuals were activated with Con A (5µg/ml) and then treated with Silymarin, Rapamycin and FK506 in various concentrations (0.001, 0.01, 0.1, 1, 10,100 and 200M) for 5 days. PBMCs were examined for proliferation using CFSE assay and the concentration that inhibited 50% of the cell proliferation (IC50) was determined for each treatment. For apoptosis assay using flow cytometry, PBMCs were activated with Con A and treated with IC50 dose of Silymarin, Rapamycin and FK506 for 5 days, then cell apoptosis was analysed by FITC-annexin V/PI staining and flow cytometry. The effects of Silymarin, Rapamycin and FK506 on the activation of PARP (poly ADP ribose polymerase) pathway in PBMCs stimulated with Con A and treated with IC50 dose of drugs for 5 days evaluated using the PathScan cleaved PARP sandwich ELISA kit. Results: This study showed that Silymarin had the ability to inhibit T cell proliferation in vitro. Moreover, our results indicated that 100 μM (P < 0.001) and 200 μM (P < 0.001) of Silymarin has more inhibitory effect on T cells proliferation than FK506 and Rapamycin. Our data showed that the effective doses (IC50) of Silymarin, FK506 and Rapamycin were 3×10-5 µM, 10-8 µM and 10-6 µM respectively. Data showed that the inhibitory effect of Silymarin, FK506 and Rapamycin on T cell proliferation was not due to cytotoxicity and none of these drugs at IC50 concentration had not affected the level of cleaved PARP. Conclusion: Silymarin could be a good candidate for immunosuppressive therapy for certain medical conditions with superior efficacy and lesser toxicity in comparison with other immunosuppressive drugs.

Keywords: silymarin, immunosuppressive effect, rapamycin, immunology

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Authors: D. Kuvshinov, A. Siswanto, W. Zimmerman

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A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil can also be used as a food stock due to its significant nutrition content. The limitations for utilizing the oil as a food stock are mainly due to a toxicity of PE. Nowadays a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence. Ozone is considered as a strong oxidative agent. It reaction with PE it attacks the carbon double bond of PE. This modification of PE molecular structure results into nontoxic ester with high lipid content. This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is a simultaneous application of new microscale plasma unit for ozone production and patented gas oscillation technology. In combination with a reactor design the technology permits ozone injection to the water-TPA mixture in form of microbubbles. The efficacy of a heterogeneous process depends on diffusion coefficient which can be controlled by contact time and interface area. The low velocity of rising microbubbles and high surface to volume ratio allow fast mass transfer to be achieved during the process. Direct injection of ozone is the most efficient process for a highly reactive and short lived chemical. Data on the plasma unit behavior are presented and influence of the gas oscillation technology to the microbubbles production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown.

Keywords: microbubble, ozonolysis, synthetic phorbol ester, chemical engineering

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Authors: Malay K. Das, Bhupen Kalita

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The poor oral bioavailability of resveratrol (RSV) due to presystemic metabolism can be avoided via dermal route of administration. The hydrophilic-lipophilic nature of resveratrol-phospholipid complex (RSVPs) favors the delivery of resveratrol via the skin. The RSVPs embedded polymeric patch with moderate adhesiveness was developed for dermal application for sustained anti-inflammatory effect. The prepared patches were evaluated for various physicochemical properties, surface morphology by SEM, TEM, and compatibility of patch components by FT-IR and DSC studies. The dermal flux of the optimized patch formulation was found to be at 4.28 ± 0.48 mg/cm2/24 h. The analysis of skin extract after permeation study revealed the presence of resveratrol, which confirmed the localization of RSVPs in the skin. The stability of RSVPs in the polymeric patch and the physiologic environment was confirmed by FE-SEM studies on the patches after drug release and skin permeation studies. The RSVPs particles released from the polymer matrix maintaining the structural integrity and permeate the keratinized horney layer of skin. The optimized patch formulation showed sustained anti-inflammatory effect (84.10% inhibition of inflammation at 24 h) in carrageenan-induced rat paw edema model compared to marketed diclofenac sodium gel (39.58% inhibition of inflammation at 24 h). The CLSM study confirmed the localization of RSVPs for a longer period, thus enabling drug targeting to the dermis for sustained anti-inflammatory effect. Histological studies with phase contrast trinocular microscope suggested no alteration of skin integrity and no evidence of the presence of inflammatory cells after exposure to the permeants. The patch was found to be safe for skin application as evaluated by Draize method for skin irritation scoring in a rabbit model. These results suggest the therapeutic efficacy of the developed patch in both acute and chronic inflammatory diseases.

Keywords: resveratrol-phospholipid complex, skin delivery, sustained anti-inflammatory effect, inflammatory diseases, dermal patch

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Authors: Mahshid Hodjat, Maryam Baeeri, Mohammad Amin Rezvanfar, Mohammad Abdollahi

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Ethephon is one of the most widely used plant growth regulator in agriculture that its application has been increased in recent years. The toxicity of organophosphate compounds is mostly attributed to their potent inhibition of acetylcholinesterase and their involvement in neurodegenerative disease. Although there are few reports on butyrylcholinesterase inhibitory role of ethephon, still there is no evidence on neurotoxicity and genotoxicity of this compound. The aim of the current study is to assess the potential genotoxic effect of ethephon using two genotoxic endpoints; γH2AX expression and comet assay on embryonic murine fibroblast. γH2AX serves as an early and sensitive biomarker for evaluating the genotoxic effects of chemicals. Oxidative stress biomarkers, including intracellular reactive oxygen species, lipid peroxidation and antioxidant capacity were also examined. The results showed a significant increase in cell proliferation 24h post-treatment with 10, 40,160µg/ml ethephon. The γH2AX expression and γH2AX foci count per cell were increased at low concentration of ethephon that was concomitant with increased DNA damage break at 40 and 160 µg/ml as illustrated by increased comet tail moment. A significant increase in lipid peroxidation and ROS formation were observed at 160 µg/ml and higher doses. The results showed that low-dose of ethephon promoted cell proliferation while induce DNA damage, raising the possibility of ethephon mutagenicity. Ethephon-induced genotoxic effect of low dose might not related to oxidative damage. However, ethephon was found to increase oxidative stress at higher doses, lead to cellular cytotoxicity. Taken together, all data indicated that ethylene, deserves more attention as a plant regulator with potential genotoxicity for which appropriate control is needed to reduce its usage.

Keywords: ethephon, DNA damage, γH2AX, oxidative stress

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Authors: Yogita Patil-Sen

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Magnetic nanoparticles such as those made of iron oxide have been widely explored as biocatalysts, contrast agents, and drug delivery systems. However, some of the challenges associated with these particles are agglomeration and biocompatibility, which lead to concern of toxicity of the particles, especially for drug delivery applications. Coating the particles with biocompatible materials such as lipids and peptides have shown to improve the mentioned issues. Thus, these core-shell type nanoparticles are emerging as the new class of nanomaterials for targeted drug delivery applications. In this study, various types of core-shell magnetic nanoparticles are prepared and characterized using techniques, such as Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM) and Thermogravimetric Analysis (TGA). The heating ability of nanoparticles is tested under oscillating magnetic field. The efficacy of the nanoparticles as drug carrier is also investigated. The loading of an anticancer drug, Doxorubicin at 18 °C is measured up to 48 hours using UV-visible spectrophotometer. The drug release profile is obtained under thermal incubation condition at 37 °C and compared with that under the influence of oscillating field. The results suggest that the core-shell nanoparticles exhibit superparamagnetic behaviour, although, coating reduces the magnetic properties of the particles. Both the uncoated and coated particles show good heating ability, again it is observed that coating decreases the heating behaviour of the particles. However, coated particles show higher drug loading efficiency than the uncoated particles and the drug release is much more controlled under the oscillating magnetic field. Thus, the results strongly indicate the suitability of the prepared core-shell type nanoparticles as drug delivery vehicles and their potential in magnetic hyperthermia applications and for hyperthermia cancer therapy.

Keywords: core-shell, hyperthermia, magnetic nanoparticles, targeted drug delivery

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Authors: Mohamed Ahmed Tony, Fayez Abaza

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The effects of a dietary supplement of rumen-protected choline on feed intake, milk yield, milk composition and some blood metabolites were evaluated in transition dairy cows. Forty multiparous cows were blocked into 20 pairs and then randomly allocated to either one of 2 treatments. The treatments were supplementation either with or without (control) rumen-protected choline. Treatments were applied from 2 weeks before and until 8 weeks after calving. Both groups received the same basal diet as total mixed ration. Additionally, 50 g of a rumen-protected choline supplement (25% rumen protected choline chloride) was added individually in the feed. Individual feed intake, milk yield, and body weight were recorded daily. Milk samples were analyzed weekly for fat, protein, and lactose content. Blood was sampled at week 2 before calving, d 1, d 4, d 7, d 10, week 2, week 3, and week 8 after calving. Glucose, triglycerids, nonesterified fatty acids, and β-hydroxybutyric acid in blood were analysed. The results revealed that choline supplementation increased DM intake from 16.5 to 18.0 kg/d and, hence, net energy intake from 99.2 to 120.5 MJ/d at the intercept of the lactation curve at 1 day in milk. Choline supplementation had no effect on milk yield, milk fat yield, or lactose yield. Milk protein yield was increased from 1.11 to 1.22 kg/d at the intercept of the lactation curve. Choline supplementation was associated with decreased milk fat concentration at the intercept of the lactation curve at 1 day in milking, but the effect of choline on milk fat concentration gradually decreased as lactation progressed. Choline supplementation decreased the concentration of blood triglycerids during the first 4 wk after parturition. Choline supplementation had no effect on energy-corrected milk yield, energy balance, body weight and body condition score. Results from this study suggest that fat metabolism in periparturient dairy cows is improved by choline supplementation during the transition period and this may potentially decrease the risk for metabolic disorders in the periparturient dairy cow.

Keywords: choline, dairy cattle, transition cow, triglycerids

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Authors: Debajyoti Bose

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Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Chitosan is a positively charged natural biodegradable and biocompatible polymer. It is a linear polysaccharide consisting of β-1,4 linked monomers of glucosamine and N-acetylglucosamine. Chitosan can be mainly obtained from fungal sources during large fermentation process. In this study,three different fungal strains Aspergillus niger NCIM 1045, Aspergillus oryzae NCIM 645 and Mucor indicus MTCC 3318 were used for the production of chitosan. The growth mediums were optimized for maximum fungal production. The produced chitosan was characterized by determining degree of deacetylation. Chitosan possesses one reactive amino at the C-2 position of the glucosamine residue, and these amines confer important functional properties to chitosan which can be exploited for biofabrication to generate various chemically modified derivatives and explore their potential for pharmaceutical field. Chitosan nanoparticles were prepared by ionic cross-linking with tripolyphosphate (TPP). The major effect on encapsulation and release of protein (e.g. enzyme diastase) in chitosan-TPP nanoparticles was investigated in order to control the loading and release efficiency. It was noted that the chitosan loading and releasing efficiency as a nanocapsule, obtained from different fungal sources was almost near to initial enzyme activity(12026 U/ml) with a negligible loss. This signify, chitosan can be used as a polymeric drug as well as active component or protein carrier material in dosage by design due to its appealing properties such as biocompatibility, biodegradability, low toxicity and relatively low production cost from abundant natural sources. Based upon these initial experiments, studies were also carried out on modification of chitosan based nanocapsules incorporated with physiologically important enzymes and nutraceuticals for target delivery.

Keywords: fungi, chitosan, enzyme, nanocapsule

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Authors: Nana Gorgiladze, Tamar Gaprindashvili, Mikheil Shavdia, Zurab Pagava

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Introduction/Purpose Chemotherapy is a common treatment for breast cancer, but it can also cause damage to the heart and blood vessels. This damage, known as cancer therapy-related cardiovascular toxicity (CTR-CVT), can increase the risk of heart failure and death in breast cancer patients. The left ventricle is often affected by CTR-CVT, but the right ventricle (RV) may also be vulnerable to CTR-CVT and may show signs of dysfunction before the left ventricle. The study aims to investigate how the RV function changes during chemotherapy for breast cancer by using conventional echocardiographic and global longitudinal strain (GLS) techniques. By measuring the GLS strain of the RV, researchers tend to detect early signs of CTR-CVT and improve the management of breast cancer patients. Methods The study was conducted on 28 women with low cardiovascular risk who received anthracycline chemotherapy for breast cancer. Conventional 2D echocardiography (LVEF, RVS’, TAPSE) and speckle-tracking echocardiography (STE) measurements of the left and right ventricles (LVGLS, RVGLS) were used to assess cardiac function before and after chemotherapy. All patients had normal LVEF at the beginning of the study. Cardiotoxicity was defined as a new LVEF reduction of 10 percentage points to an LVEF of 40-49% and/or a new decline in GLS of 15% from baseline, as proposed by the most recent cardio-oncology guideline. ResultsThe research found that the LVGLS decreased from -21.2%2.1% to -18.6%2.6% (t-test = -4.116; df = 54, p=0.001). The change in value LV-GLS was 2.6%3.0%. The mean percentage change of the LVGLS was 11,6%13,3%; p=0.001. Similarly, the right ventricular global longitudinal strain (RVGLS) decreased from -25.2%2.9% to -21.4%4.4% (t-test = -3.82; df = 54, p=0.001). The RV-GLS value of change was 3.8%3.6%. Likewise, the percentage decrease of the RVGLS was 15,0%14,3%, p=0.001.However, the measurements of the right ventricular systolic function (RVS) and tricuspid annular plane systolic excursion (TAPSE) were insignificant, and the left ventricular ejection fraction ( LVEF) remained unchanged.

Keywords: cardiotoxicity, chemotherapy, GLS, right ventricle

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Authors: Włodzimierz Przewodowski, Agnieszka Przewodowska

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Colloidal metal nanoparticles have drawn increasing attention in the field of phytopathology because of their unique properties and possibilities of applications. Their antibacterial activity, no induction of the development of pathogen resistance and the ability to penetrate most of biological barriers make them potentially useful in the fighting against dangerous pathogens. These properties are very important in the case of protection of strategic crops in the world, like potato - fourth crop in the world - which is host to numerous pathogenic microorganisms causing serious diseases, significantly affecting yield and causing the economic losses. One of the most important and difficult to reduce pathogen of potato plant is quarantine bacterium Clavibacter michiganensis ssp. sepedonicus (Cms) responsible for ring rot disease. Control and detection of these pathogens is very complicated. Application of healthy, certified seed material as well as hygiene in potato production and storage are the most efficient ways of preventing of ring rot disease. Currently used disinfectants and pesticides, have many disadvantages, such as toxicity, low efficiency, selectivity, corrosiveness, and the inability to eliminate the pathogens in potato tissue. In this situation, it becomes important to search for new formulations based on components harmful to health, yet efficient, stable during prolonged period of time and a with wide range of biocide activity. Such capabilities are offered by the latest generation of biocidal nanoparticles such as colloidal metals. Therefore the aim of the presented research was to develop newly antibacterial preparation based on colloidal metal nanoparticles and checking their influence on the Cms bacteria. Our preliminary results confirmed high efficacy of the nano-colloids in controlling the this selected pathogen.

Keywords: clavibacter michiganensis ssp. sepedonicus, colloidal metal nanoparticles, phytopathology, bacteria

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Authors: Mohit Wadhawan, Sushma Rathaur

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Lymphatic filariasis, also called elephantiasis is a tropical disease afflicting over 120 million people in 81 countries worldwide. Existing anti filarial drugs are effective against the larval stages of filarial parasites which call for an urgent need of drugs which are macrofilaricidal. Identification of molecular targets crucial for survival of filarial parasites is a prerequisite for drug designing. Prolyl oligopeptidase (POP) is one such crucial enzyme involved in the maturation and degradation of neuropeptides and peptide hormones. We have identified this peptidase in the bovine filarial parasite, Setaria cervi. Effect of inhibition of POP on the proteome profile of filarial parasite has been discussed in this study. Filarial parasites were exposed to Z-pro-prolinal (ZPP), a specific POP inhibitor for 8 h and the motility and viability of the parasites was observed. It significantly reduced the motility and viability of the parasites. To study the proteome profile, the cytosolic, endoplasmic reticulum (ER) and mitochondrial extracts of the adult female parasites were subjected to 2-dimensional electrophoresis. As analyzed by the PD-Quest software, the ZPP caused the alteration in the different subcellular proteins, and the significantly altered proteins were identified using MALDI-MS/MS spectrometry. The major proteins identified were found to play important role in diverse biological functions like signaling, redox regulation, energy metabolism, stress response, and cytoskeleton formation. Moreover, we found upregulation in the calcium binding proteins such as calreticulin, calponin, and calpain-6 suggesting that POP inhibition regulates calcium release. This relates to earlier reports that POP plays non-catalytic role in inositol 1,4,5-trisphosphate (IP3) signaling inducing release of calcium from ER. Taken together, the data demonstrated that inhibition of prolyl oligopeptidase alter the overall proteome signifying its role in survival of the filarial parasites. Thus this study provides a basis for the use of POP as a chemotherapeutic target for the treatment of lymphatic filariasis.

Keywords: lymphatic filariasis, setaria cervi, prolyl oligopeptidase, proteomics

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Authors: Abdelkarim Mahdhi, Fdhila Kais, Faouzi Lamari, Zeineb Hmila, Fathi Kamoun, Maria Ángeles Esteban, Amina Bakhrouf

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Aquaculture is the world’s fastest growing food-production sector. However, one of the most serious problems regarding the culture of marine fishes is the mortality associated with pathogenic bacteria that occurs in the critical phases of larval development. Conventional approaches, such as the use of antimicrobial drugs to control diseases, have had limited success in the prevention or cure of aquatic diseases. Promising alternatives to antibiotics are probiotics, which are food supplements consisting of live microorganisms that benefit the host organism. In the search for more effective and environmentally friendly treatments with probionts against pathogenic species in shrimp larval culture, the probiotic properties of Bacillus strains isolated from Artemia culture such as antibacterial activity, adhesion, pathogenicity, toxicity and the effect of marine stress on viability and survival were investigated, as well as the changes occurring in their properties. Analyses showed that these bacteria corresponded to the genus Bacillus sp. Antagonism and adherence assays revealed that these strains have an inhibitory effect against pathogenic bacteria in vitro and in vivo conditions and are fairly adherent. Challenge tests performed with Artemia larvae provided evidence that the tested Bacillus strains were neither pathogenic nor toxic to the host. The tested strains maintained their viability and their probiotic properties during the period of study. The results suggest that the tested strains have suffered changes allowing them to survive in seawater in the absence of nutrients and outside their natural host, identifying them as potential probiotic candidates for Artemia culture.

Keywords: bacillus, probiotic, cell viability, stress response

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Authors: Sudeshna Mukherjee, Leena Fageria, R. Venkataramana Dilip, Rajdeep Chowdhury, Jitendra Panwar

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Metal nanoparticles in recent years have gained importance in cancer therapy due to their enhanced permeability retention effect. Among various nanomaterials, silver nanoparticles (AgNPs) have received considerable attention due to their unique properties like conductivity, chemical stability, relative lower toxicity and outstanding therapeutic potential, such as anti-inflammatory, antimicrobial and anti-cancerous activities. In this study, we took a greener approach to synthesize silver nanoparticle from fungus and analyze its effects on both epithelial and mesenchymal derived cancer cells. Much research has been done on nanoparticle-induced apoptosis, but little is known about its role in autophagy. In our study, the silver nanoparticles were seen to induce autophagy which was analyzed by studying the expression of several autophagy markers like, LC3B-II and ATG genes. Monodansylcadaverine (MDC) assay also revealed the induction of autophagy upon treatment with AgNPs. Inhibition of autophagy by chloroquine resulted in increased cell death suggesting autophagy as a survival strategy adopted by the cells. In parallel to autophagy induction, silver nanoparticles induced ROS accumulation. Interestingly, autophagy inhibition by chloroquine increased ROS level, resulting in enhanced cell death. We further analyzed MAPK signaling upon AgNP treatment. It was observed that along with autophagy, activation of JNK signaling served as pro-survival while ERK signaling served as a pro-death signal. Our results provide valuable insights into the role of autophagy upon AgNP exposure and provide cues to probabilistic strategies to effectively sensitize cancer cells.

Keywords: autophagy, JNK signalling, reactive oxygen species, silver nanoparticles

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Authors: Mohamed H. Khalifa, Fikry I. El-Shahawi, Nabil A. Mansour

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The cotton leafworm, Spodoptera littoralis (Boisduval) is a major insect pest of vegetables and cotton crops in Egypt, and exhibits different levels of tolerance to certain insecticides. Chlorantraniliprole has been registered recently in Egypt for control this insect. The susceptibilities of three S. littoralis populations collected from El Behaira governorate, north Egypt to chlorantraniliprole were determined by leaf-dipping technique on 4^th instar larvae. Obvious variation of toxicity was observed among the laboratory susceptible, and three field populations with LC₅₀ values ranged between 1.53 µg/ml and 6.22 µg/ml. However, all the three field populations were less susceptible to chlorantraniliprole than a laboratory susceptible population. The most tolerant populations were sampled from El Delengat (ED) Province where S. littoralis had been frequently challenged by insecticides. Certain enzyme activity assays were carried out to be correlated with the mechanism of the observed field population tolerance. All field populations showed significantly enhanced activities of detoxification enzymes compared with the susceptible strain. The regression analysis between chlorantraniliprole toxicities and enzyme activities revealed that the highest correlation is between α-esterase or β-esterase (α-β-EST) activity and collected field strains susceptibility, otherwise this correlation is not significant (P > 0.05). Synergism assays showed the ED and susceptible strains could be synergized by known detoxification inhibitors such as piperonyl butoxide (PBO), triphenyl phosphate (TPP) and diethyl-maleate (DEM) at different levels (1.01-8.76-fold and 1.09-2.94 fold, respectively), TPP showed the maximum synergism in both strains. The results show that there is a correlation between the enzyme activity and tolerance, and carboxylic-esterase (Car-EST) is likely the main detoxification mechanism responsible for tolerance of S. littoralis to chlorantraniliprole.

Keywords: chlorantraniliprole, detoxification enzymes, Egypt, Spodoptera littoralis

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Authors: Emad A. Shalaby

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Cancer is a disease that causes abnormal cell proliferation and invades nearby tissues. Lung cancer is the second most frequent cancer worldwide. Natural anti-cancer drugs have been developed with low side effects and toxicity. Citrus peels and extracts have been demonstrated to have significant pharmacological and physiological effects as a result of the high concentration of phenolic compounds found in citrus fruits, particularly peels. Tangerine peels can serve as an effective source of bioactive substances such as phenolics, flavonoids, and catechins, which have antioxidant, antibacterial, anticancer, and anti-inflammatory properties. Consequently, this work aims to determine the anticancer activity of ethanol extract of Tangerine peels against the A549 cell line and identify the phenolic compound profile (19 compounds) by using HPLC. Anticancer and antioxidant potentials of the extract were evaluated by MTT assay and TLC- TLC-bioautography sprayed with DPPH reagent, respectively. The obtained results revealed that tangerine peel extract showed significant activity against the A549 cell line with IC50 of 97.66 μg/mL. HPLC analysis proved that the highest concentration is naringenin 464.05 mg/g. More studies indicate that naringenin has significant anticancer potential on A549 cancer cells. The results showed that naringenin binds t0 EGFR protein in A549 with high binding affinity and thus may reduce lung cancer cell migration and enhance the apoptosis of cancer cells. From the obtained results it could be concluded that tangerine peel extract is an effective anti-cancer agent that may potentially serve as a natural therapeutic option for lung cancer treatment.

Keywords: tangerine peel, A549 cell line, anticancer, naringenin, HPLC analysis, naringenin, TLC bioautography

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Authors: Faizan Hassan, Seema Kumari, V. P. Singh, Pradeep Das, Diwakar Singh Dinesh

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Phlebotomus argentipes is an established vector for Visceral Leishmaniasis in Indian subcontinent. Laboratory colonization of Sand flies is imperative in research on vectors, which requires a proper diet for their larvae and adult growth that ultimately affects their survival and fecundity. In most of the laboratories, adult Sand flies are reared on rabbit blood feeding/artificial blood feeding and their larvae on fine grinded rabbit faeces as a sole source of food. Rabbit faeces are unhygienic, difficult to handle, high mites infestation as well as owing to bad odour which creates menacing to human users ranging from respiratory problems to eye infection and most importantly it does not full fill all the nutrients required for proper growth and development. It is generally observed that the adult emergence is very low in comparison to egg hatched, which may be due to insufficient food nutrients provided to growing larvae. To check the role of food nutrients on larvae survival and adult emergence, a high protein rich artificial diet for sand fly larvae were used in this study. The composition of artificial diet to be tested includes fine grinded (9 gm each) Rice, Pea nuts & Soyabean balls. These three food ingredients are rich source of all essential amino acids along with carbohydrate and minerals which is essential for proper metabolism and growth. In this study artificial food was found significantly more effective for larval development and adult emergence than rabbit faeces alone (P value >0.05). The weight of individual larvae was also found higher in test pots than the control. This study suggest that protein plays an important role in insect larvae development and adding carbohydrate will also enhances the fecundity of insects larvae.

Keywords: artificial food, nutrients, Phlebotomus argentipes, sand fly

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Authors: Mohammed A. Alshehri

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Salvia officinalis is an aromatic plant member of the mint (Labiatae) family. It is popular kitchen herb. Not surprise to find that the name of this herb related to cure, in Latin language Salvia means to cure where officinalis means medicinal which answer why the sage has a top place in the list of medicinal plants. The aim of the present study was to assess the genetic damage and cytological changes caused by exposure of the test organism (Rattusrattus) to Salvia officinals. For this purpose, adult female rats, weighing 200–250 g, were used as donors. A total of 36 adult Wister male rats were randomly assigned to five groups: the experimental groups (rats were intraperitonealy injected with Salvia officinalis pure extract at (0.1, 0.2, 0.5, 0.1mg/kg body weight, the same dose was administered once a day. Control group (rats were injected intraperitonealy physiological saline. And positive control were injected with Cyclophosphamide. On the 21st days following Salvia officinalis pure extract exposure, rats were sacrificed, and samples of bone marrow were collected. Following that, we performed a micronuclei (MN) test using MNNCE (Micro-nucleated normocromatic erythrocytes) and MNPCE (Micronucleated polychromatic erythrocytes), NDI (Nuclear division index), and cytological parameters using NDCI (nuclear division cytotoxicity index), necrotic, and apoptotic cells in rat's bone marrow samples. Results showed that there was a no significant increase in the frequency of micro-nucleatedas well as in cytological parameters in bone marrow cells. In light of these results, if Salvia officinalis pure extract may considered to be safe from the stand point of genotoxicity and cytotoxicity effects.

Keywords: Salvia officinalis, micronucleus, NDI, NDCI, toxicity, chromosomal aberrations

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Authors: Yonosuke Murayama

Abstract:

We have developed and studied a metastable beta Ti alloy, which shows super-elasticity and low Young’s modulus according to the phase stability of its beta phase. The super-elasticity and low Young’s modulus are required in a wide range of applications in various industrial fields. For example, the metallic implant with low Young’s modulus and non-toxicity is desirable because the large difference of Young’s modulus between the human bone and the implant material may cause a stress-shielding phenomenon. We have investigated the role of Sn and Al in metastable beta Ti-Cr-Sn, Ti-Cr-Al, Ti-V-Sn, and Ti-V-Al alloys. The metastable beta Ti-Cr-Sn, Ti-Cr-Al, Ti-V-Sn, and Ti-V-Al alloys form during quenching from the beta field at high temperature. While Cr and V act as beta stabilizers, Sn and Al are considered as elements to suppress the athermal omega phase produced during quenching. The athermal omega phase degrades the properties of super-elasticity and Young’s modulus. Although Al and Sn as single elements are considered as an alpha stabilizer and neutral, respectively, Sn and Al acted also as beta stabilizers when added simultaneously with beta stabilized element of Cr or V in this experiment. The quenched microstructure of Ti-Cr-Sn, Ti-Cr-Al, Ti-V-Sn, and Ti-V-Al alloys shifts from martensitic structure to beta single-phase structure with increasing Cr or V. The Young’s modulus of Ti-Cr-Sn, Ti-Cr-Al, Ti-V-Sn, and Ti-V-Al alloys decreased and then increased with increasing Cr or V, each showing its own minimum value of Young's modulus respectively. The composition of the alloy with the minimum Young’s modulus is a near border composition where the quenched microstructure shifts from martensite to beta. The border composition of Ti-Cr-Sn and Ti-V-Sn alloys required only less amount of each beta stabilizer, Cr or V, than Ti-Cr-Al and Ti-V-Al alloys. This indicates that the effect of Sn as a beta stabilizer is stronger than Al. Sn and Al influenced the competitive relation between stress-induced martensitic transformation and slip deformation. Thus, super-elastic properties of metastable beta Ti-Cr-Sn, Ti-Cr-Al, Ti-V-Sn, and Ti-V-Al alloys varied depending on the alloyed element, Sn or Al.

Keywords: metastable beta Ti alloy, super-elasticity, low Young’s modulus, stress-induced martensitic transformation, beta stabilized element

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Authors: Kabange Kasumbwe, Viresh Mohanlall, Bharti Odhav, Venu Narayanaswamy

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Coumarins are naturally occurring plant metabolites known for their pharmacological properties such as anticoagulant, antimicrobial, anticancer, antioxidant, anti-inflammatory and antiviral properties. The pharmacological and biochemical properties and curative applications of coumarins depend on the substitution around the coumarin core structure. In the present study, seven halogenated coumarins CMRN1-CMRN7 were synthesized and evaluated for their anticancer activity. The cytotoxicity potential of the test compounds was evaluated against UACC62 (Melanoma), MCF-7 (Breast cancer) and PBM (Peripheral Blood Mononuclear) cell lines using MTT assay keeping doxorubicin as standard drug. The apoptotic potential of the coumarin compounds was evaluated against UACC62 (Melanoma) cell by assessing their morphological changes, membrane change, mitochondria membrane potential; pro-apoptotic changes were investigated using the AnnexinV-PI staining, JC-1, caspase-3 enzyme kits respectively on flow cytometer. The synthetic coumarin has strongly suppressed the cell proliferation of UACC-62 (Melanoma) and MCF-7 (Breast) Cancer cells, the higher toxicity of these compounds against UACC-62 (Melanoma) and MCF-7 (Breast) were CMRN3, CMRN4, CMRN5, CMRN6. However, compounds CMRN1, CMRN2, and CMRN7 had no significant inhibitory effect. Furthermore the active compounds CMRN3, CMRN4, CMRN5, CMRN6 exerted antiproliferative effects through apoptosis induction against UACC-62 (Melanoma), suggesting their potential could be considered as attractive lead molecules in the future for the development of potential anticancer agents since one of the important criteria in the development of therapeutic drugs for cancer treatment is to have high selectivity and less or no side-effects on normal cells and these compounds had no inhibitory effect against the PBMC cells.

Keywords: coumarin, MTT, apoptosis, cytotoxicity

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Authors: Abdulmalik Altuwayjiri, Milad Pirhadi, Mohammed Kalafy, Badr Alharbi, Constantinos Sioutas

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In this study, we investigated the chemical and toxicological characteristics of PM10 in the metropolitan area of Riyadh, Saudi Arabia. PM10 samples were collected on quartz and teflon filters during cold (December 2019–April 2020) and warm (May 2020–August 2020) seasons, including dust and non-dust events. The PM10 constituents were chemically analyzed for their metal, inorganic ions, and elemental and organic carbon (EC/OC) contents. Additionally, the PM10 oxidative potential was measured by means of the dithiothreitol (DTT) assay. Our findings revealed that the oxidative potential of the collected ambient PM10 samples was significantly higher than those measured in many urban areas worldwide. The oxidative potential of the collected ambient PM¹⁰⁻ samples was also higher during dust episodes compared to non-dust events, mainly due to higher concentrations of metals during these events. We performed Pearson correlation analysis, principal component analysis (PCA), and multi-linear regression (MLR) to identify the most significant sources contributing to the toxicity of PM¹⁰⁻ The results of the MLR analyses indicated that the major pollution sources contributing to the oxidative potential of ambient PM10 were soil and resuspended dust emissions (identified by Al, K, Fe, and Li) (31%), followed by secondary organic aerosol (SOA) formation (traced by SO₄-² and NH+₄) (20%), and industrial activities (identified by Se and La) (19%), and traffic emissions (characterized by EC, Zn, and Cu) (17%). Results from this study underscore the impact of transported dust emissions on the oxidative potential of ambient PM10 in Riyadh and can be helpful in adopting appropriate public health policies regarding detrimental outcomes of exposure to PM₁₀-

Keywords: ambient PM10, oxidative potential, source apportionment, Riyadh, dust episodes

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Authors: Ashit Syngle, Inderjit Verma, Pawan Krishan

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Therapeutic approaches used previously relied on disease-modifying antirheumatic drugs (DMARDs) that had only partial clinical benefit and were associated with significant toxicity. Spironolactone, an oral aldosterone antagonist, suppresses inflammatory mediators. Clinical efficacy of spironolactone compared with placebo in patients with active psoriatic arthritis despite treatment with prior traditional DMARDs. In the 24-week, placebo-controlled study patients (n=31) were randomized to placebo and spironolactone (2 m/kg/day). Patients on background concurrent DMARDs continued stable doses (methotrexate, leflunomide, and/or sulfasalazine). Primary outcome measures were the assessment of disease activity measures i.e. 28-joint disease activity score (DAS28) and diseases activity in psoriatic arthritis (DAPSA) at week 24. The key secondary endpoint was change from baseline in Health Assessment Questionnaire–Disability Index (HAQ-DI) at week 24. Additional efficacy outcome measures at week 24 included improvements in the markers of inflammation (ESR and CRP) and pro-inflammatory cytokines TNF-α, IL-6 and IL-1. At week 24, spironolactone significantly reduced disease activity measure DAS-28 (p<0.001) and DAPSA (p=0.001) compared with placebo. Significant improvements in key secondary measures HAQ-DI (disability index) were evident with spironolactone (p=0.02) versus placebo. After week 24, there was significant reduction in pro-inflammatory cytokines level TNF-α, IL-6 (p<0.01) as compared with placebo group. However, there was no significant improvement in IL-1 in both treatment and placebo groups. There were minor side effects which did not mandate stopping of spironolactone. No change in any biochemical profile was noted after spironolactone treatment. Spironolactone was effective in the treatment of PsA, improving disease activity, physical function and suppressing the level of pro-inflammatory cytokines. Spironolactone demonstrated an acceptable safety profile and was well tolerated.

Keywords: spironolactone, inflammation, inflammatory cytokine, psoriatic arthritis

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Authors: Aniekan Peter, ECS Naidu, Edidiong Akang, U. Offor, R. Kalhapure, A. A. Chuturgoon, T. Govender, O. O. Azu

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Introduction: Nano-drugs are novel innovations in the management of human immunodeficiency virus (HIV) pandemic, especially resistant strains of the virus in their sanctuary sites: testis and the brain. There are safety concerns to be addressed to achieve the full potential of this new drug delivery system. Aim of study: Our study was designed to investigate toxicity profile of Tenofovir Nanoparticle (TDF-N) synthesized by University of Kwazulu-Natal (UKZN) Nano-team for prevention and treatment of HIV infection. Methodology: Ten adult male Sprague-Dawley rats maintained at the Animal House of the Biomedical Resources Unit UKZN were used for the study. The animals were weighed and divided into two groups of 5 animal each. Control animals (A) were administered with normal saline. Therapeutic dose (4.3 mg/kg) of TDF-N was administered to group B. At the end of four weeks, animals were weighed and sacrificed. Liver and kidney were removed fixed in formal saline, processed and stained using H/E, PAS and MT stains for light microscopy. Serum was obtained for renal function test (RFT), liver function test (LFT) and full blood count (FBC) using appropriate analysers. Cellular measurements were done using ImageJ and Leica software 2.0. Data were analysed using graph pad 6, values < 0.05 were significant. Results: We reported no histological alterations in the liver, kidney, FBC, LFT and RFT between the TDF-N animals and saline control. There were no significant differences in weight, organo-somatic index and histological measurements in the treatment group when compared with saline control. Conclusion/recommendations: TDF-N is not toxic to the liver, kidney and blood cells in our study. More studies using human subjects is recommended.

Keywords: tenofovir nanoparticles, liver, kidney, blood cells

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Authors: Islam Zeb

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The water of poor quality used for irrigation purposes has the potential to be the direct source of contamination and a vehicle for spreading contamination in the field. A number of wide-ranging review articles have been published that highlight irrigation water as a source of heavy metals toxicity which leads to chronic diseases in the human body. Here a study was planned to determine the microbial and heavy metals status of irrigation water collected from various locations of district Swat in various months. The analyses were carried out at the Environmental Horticulture Laboratory, Department of Horticulture, The University of Agriculture Peshawar, during the year 2018 – 19. The experiment was laid out in Randomized Complete Block Design (RCBD) with two factors and three replicates. Factor A consist of different locations and factor B represent various months. The result of heavy metals concentration in different regions, maximum Lead, Cadmium, Chromium, Nickel and Copper (4.27, 0.56, 0.81, 1.33 and 1.51 mg L-1 respectively) were noted for the irrigation water samples collected from Mingora while minimum Lead, Cadmium, Chromium, Nickel and Copper concentration (2.59, 0.30, 0.27, 0.40 and 0.54 mg L-1 respectively) were noted for the samples of matta. Whereas results of heavy metals content in irrigation water samples for various months maximum content of Lead, Cadmium, Chromium, Nickel and Copper (4.56, 0.63, 1.15, 1.31 and 1.48 mg L-1 respectively) were noted for the samples collected in Jan/Feb while lowest values for Lead, Cadmium, Chromium, Nickel and Copper (2.38, 0.24, 0.21, 0.41 and 0.52 mg L-1 respectively) were noted in the samples of July/August. A significant interaction was found for all the studied parameters. It was concluded that the concentration of heavy metal was maximum in irrigation water samples collected from the Mingora location during the month of Jan/Feb because Mingora is the most polluted area as compared to other studied regions, whereas the water content in winter goes to freeze and mostly contaminated water is used for irrigation purposes.

Keywords: irrigation water, various months, different regions, heavy metals contamination, Swat

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Authors: Abdurrauf M. Gusbi, Mahmud H. Arhima, Abdurrahim A. Elouzi, Ebtisam A. Benomran, Salsabeela Elmezwghi, Aram Elhatan, Nafesa Elgusbi

Abstract:

Mass poisonings with methanol are rare but occur regularly both in developed and in non-developing countries. As a result of the tragedy that happened in the city of Tripoli Libya in March during year 2013 a number of patients were admitted to Tripoli Medical Center and Tripoli Central Hospital suffering from poisoning following ingestion of methanol by mistake. Our aims have been formulated to collect Information about those cases as much as we can from the archiving departments from the two hospitals including the number of cases that had been admitted, recovered patients and died victims. This retrospective study was planned to find out the reasons which allow those patients to drink methanol in our Muslim community and also the role of pharmacist to prevent such a disaster that claimed the lives of many people. During this tragedy 291 ospitalized patients their ages between 16-32 years old were admitted to both hospitals, total number of died 189 (121 at Tripoli medical center) and (68 at Tripoli central hospital), demographic data also shows that most of them are male (97%) and (3% female), about 4% of the patients foreigners and 96% were Libyans. There were a lot of obstacles and poor facilities at the time of patient admission as recognized in many cases including lack of first line of treatment. The morbidity was high due to the lack of antidote and availability of dialysis machines at this two main hospitals in Tripoli also according to survey done to the medical staff and also a random number of medical students shows about 28% have no idea about the first aid procedure used for methanol poisoning cases and this due to the absence of continuing education for all medical staff through the establishment of training courses on first aid, rapid diagnosis of poisoning and follow the written procedures to dealing with such cases.

Keywords: ethanol, fomepizole, methanol, poisoning

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Authors: Sahar Rakhshan, Simonetta Geninatti Crich, Diego Alberti, Rachele Stefania

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The combination of imaging and therapeutic agents in the same smart nanoparticle is a promising option to perform a minimally invasive imaging guided therapy. In this study, Low density lipoproteins (LDL), one of the most attractive biodegradable and biocompatible nanoparticles, were used for the simultaneous delivery of Paclitaxel (PTX), a hydrophobic antitumour drug and an amphiphilic contrast agent, Gd-AAZTA-C17, in B16-F10 melanoma cell line. These cells overexpress LDL receptors, as assessed by Flow cytometry analysis. PTX and Gd-AAZTA-C17 loaded LDLs (LDL-PTX-Gd) have been prepared, characterized and their stability was assessed under 72 h incubation at 37 ◦C and compared to LDL loaded with Gd-AAZTA-C17 (LDL-Gd) and LDL-PTX. The cytotoxic effect of LDL-PTX-Gd was evaluated by MTT assay. The anti-tumour drug loaded into LDLs showed a significantly higher toxicity on B16-F10 cells with respect to the commercially available formulation Paclitaxel Kabi (PTX Kabi) used in clinical applications. It was possible to demonstrate a high uptake of LDL-Gd in B16-F10 cells. As a consequence of the high cell uptake, melanoma cells showed significantly high cytotoxic effect when incubated in the presence of PTX (LDL-PTX-Gd). Furthermore, B16-F10 have been used to perform Magnetic Resonance Imaging. By the analysis of the image signal intensity, it was possible to extrapolate the amount of internalized PTX indirectly by the decrease of relaxation times caused by Gd, proportional to its concentration. Finally, the treatment with PTX loaded LDL on B16-F10 tumour bearing mice resulted in a marked reduction of tumour growth compared to the administration of PTX Kabi alone. In conclusion, LDLs are selectively taken-up by tumour cells and can be successfully exploited for the selective delivery of Paclitaxel and imaging agents.

Keywords: low density lipoprotein, melanoma cell lines, MRI, paclitaxel, personalized medicine application, theragnostic System

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Authors: Samsher Gautam, Apoorva Roy, Bhuvan Aggarwal

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Vapor absorption refrigeration systems can replace vapor compression systems in many applications as they can operate on a low-grade heat source and are environment-friendly. Widely used refrigerants such as CFCs and HFCs cause significant global warming. Natural refrigerants can be an alternative to them, among which carbon dioxide is promising for use in automotive air conditioning systems. Its inherent safety, ability to withstand high pressure and high heat transfer coefficient coupled with easy availability make it a likely choice for refrigerant. Various properties of the ionic liquid [bmim][PF₆], such as non-toxicity, stability over a wide temperature range and ability to dissolve gases like carbon dioxide, make it a suitable absorbent for a vapor absorption refrigeration system. In this paper, an absorption chiller consisting of a generator, condenser, evaporator and absorber was studied at an operating temperature of 70⁰C. A thermodynamic model was set up using the Peng-Robinson equations of state to predict the behavior of the refrigerant and absorbent pair at different points in the system. A MATLAB code was used to obtain the values of enthalpy and entropy at selected points in the system. The exergy destruction in each component and exergetic coefficient of performance (ECOP) of the system were calculated by performing an exergy analysis based on the second law of thermodynamics. Graphs were plotted between varying operating conditions and the ECOP obtained in each case. The effect of every component on the ECOP was examined. The exergetic coefficient of performance was found to be lesser than the coefficient of performance based on the first law of thermodynamics.

Keywords: [bmim][PF₆] as absorbent, carbon dioxide as refrigerant, exergy analysis, Peng-Robinson equations of state, vapor absorption refrigeration

Procedia PDF Downloads 287

Authors: Anza-Vhudziki Mboyi, Ilunga Kamika, Maggy Momba

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The aim of this study was to ascertain the survival limit and capability of commonly found wastewater protozoan (Aspidisca sp, Trachelophyllum sp, and Peranema sp) and bacterial (Bacillus licheniformis, Brevibacillus laterosporus, and Pseudomonas putida) species to remove COD while exposed to commercial nanomaterials under varying pH conditions. The experimental study was carried out in modified mixed liquor media adjusted to various pH levels (pH 2, 7 and 10), and a comparative study was performed to determine the difference between the cytotoxicity effects of commercial zinc oxide (nZnO) and silver (nAg) nanomaterials (NMs) on the target wastewater microbial communities using standard methods. The selected microbial communities were exposed to lethal concentrations ranging from 0.015 g/L to 40 g/L for nZnO and from 0.015 g/L to 2 g/L for nAg for a period of 5 days of incubation at 30°C (100 r/min). Compared with the absence of NMs in wastewater mixed liquor, the relevant environmental concentration ranging between 10 µg/L and 100 µg/L, for both nZnO and nAg caused no adverse effects, but the presence of 20 g of nZnO/L and 0.65 g of nAg/L significantly inhibited microbial growth. Statistical evidence showed that nAg was significantly more toxic compared to nZnO, but there was an insignificant difference in toxicity between microbial communities and pH variations. A significant decrease in the removal of COD by microbial populations was observed in the presence of NMs with a moderate correlation of r = 0.3 to r = 0.7 at all pH levels. It was evident that there was a physical interaction between commercial NMs and target wastewater microbial communities; although not quantitatively assessed, cell morphology and cell death were observed. Such phenomena suggest the high resilience of the microbial community, but it is the accumulation of NMs that will have adverse effects on the performance in terms of COD removal.

Keywords: bacteria, biological treatment, chemical oxygen demand (COD) and nanomaterials, consortium, pH, protozoan

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Authors: Inayat Shah, Muhammad Omar Malik, Ghareeb Alshuwaier, Ronald H. Baxendale

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Background: The balance between angiogenesis and angiostasis is important in growth and developmental processes in the body. Angiogenic and angiostatic mediators control this balance. Endostatin is one of the prominent angiostatic mediators. The marked angiostatic effect of endostatin includes inhibiting endothelial cell migration, proliferation and apoptosis. Physical activity decreases the risk and development of many angiogenesis related health problems including atherosclerosis and numerous cancers. Physiological influences of different physical activities on plasma endostatin concentration are controversial and not completely clear. Moreover, correlation of physical characteristics and metabolic predictors during physical activity on circulating endostatin is indistinct and poorly speculated. The study aimed to determine the effects of mild, moderate and vigorous exercise on the concentration of endostatin in plasma. Methodology: 22 participants, 16 males (age = 30.6 ± 7.8 years) and 6 females (age = 26.5 ± 5 years) were recruited. Weekly session of different intensities exercise based on the predicted maximum heart of the participants [60%(low), 70% (moderate) and 80% (vigorous)] were carried out. The duration and work rate for each participant was determined through sub-maximal exercise. Standardization of the session was done on total energy expenditure of the participants per session. One pre exercise and two post exercise samples were taken at intervals of 10 and 60 minutes. Results: Pre-exercise mean endostatin was 101 ± 20 ng/dl. Low intensity exercise insignificantly decreased the endostatin concentration in plasma at 10 and 60 minutes 97 ± 20 ng/dl (p= 0.5), 98 ± 23 ng/dl (p= 0.8)). However, moderate (p= 0.022, 0.004) and vigorous intensities (p ≤ 0.001, 0.02) increased the endostatin concentrations significantly at both 10 and 60 minutes intervals respectively. The effects were not significantly influenced by gender, exercise mode (walking vs. running), components of exercise (HR, Speed, Gradients, distance, duration) or metabolism during exercise (VO₂ max, VCO₂, RER, energy expenditure, rate of carbohydrate or fats oxidation). Conclusion: Low intensity exercises did not influence endostatin concentration. However, moderate to high intensity exercises significantly increase endostatin concentration and may have potential benefits.

Keywords: angiogenesis, exercise, endostatin, physical activity

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