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Proteomic investigation of the molecular mechanism of king cobra venom L-amino acid oxidase induced apoptosis of human breast cancer (MCF-7) cell line
No full textSnake venom is known for its therapeutic applications since long. Researchers have earlier demonstrated antiarthritic, anticancer, anti-inflammatory, antinociceptive activities of snake venom toxins apart from their use in the treatment of alzheimer's disease, neural trauma, parkinson's disease, stroke, etc. King cobra [Ophiophagus hannah (Cantor)] venom L-amino acid oxidase (OH-LAAO), a LAAO that possesses unusual thermal stability, also exhibits potent and selective antiproliferative activity against human tumorigenic cell lines. In this study, we investigated molecular mechanism of the enzyme induced apoptosis by examining the differential protein expressions in MCF-7 cell after treatment with the enzyme, using 2DE for separation and MALDI-TOF/TOF for protein identification. Proteomic analysis revealed a total of 21 differentially expressed proteins that are involved in various biological processes, of which 8 were involved in LAAO-induced cell death, including stress response, oxido-reduction, protein ubiquitination, proteolysis, and apoptosis. Upregulation of NADPH-cytochrome P450 reductase, in particular, may trigger excessive production of cellular ROS and contribute further to cellular oxidative stress and potentiate the cytotoxic action of the enzyme. These alterations of protein expression that are involved in different pathways or cellular functions were presumably caused by the non-specific oxidative modification of transcriptional factors, which may further modulate the activity of the signalling proteins that eventually lead to apoptosis and cell death. The results are consistent with earlier observations from gene expression studies that also demonstrated the involvement of non-specific oxidative modifications of signalling molecules in the apoptosis induced by OH-LAAO
Annual Prediction Output of an RADTIRC-PV Module
No full textThe number of solar photovoltaic (PV) installations has been increasing worldwide but the high capital cost of installation continues to be the main challenge, particularly in many developing countries. The solar concentrator, a device that focuses the sunlight onto a small area, has the potential to minimize the use of expensive PV material while maintaining the system's performance, ultimately bringing down its overall cost. This study aims to predict the annual electrical output of a specific concentrator design called the rotationally asymmetrical dielectric totally internally reflecting concentrator (RADTIRC). The aforementioned design is assumed to be installed in Berlin/Brandenburg, Germany. First, a short review of concentrators is provided. Next, a description of the RADTIRC and the previous research that revolved around it are provided. Afterwards, the key parameters that are needed to determine the annual electrical output of the RADTIRC are explained before presenting the results of the simulations. It was found that the yearly energy yield was increased by a factor of 2.29 when the RADTIRC-PV module was used when compared with the non-concentrating PV module
Proteomics, functional characterization and antivenom neutralization of the venom of Pakistani Russell's viper ( Daboia russelii ) from the wild
No full textThe venom proteome of wild Pakistani Russell's viper (Daboia russelii) was investigated through nano-ESI-LCMS/MS of the reverse-phase HPLC fractions. A total of 54 venom proteins were identified and clustered into 11 protein families. Phospholipase A2 (PLA2, 63.8%) and Kunitz-type serine protease inhibitor (KSPI, 16.0%) were most abundant, followed by snake venom serine protease (SVSP, 5.5%, mainly Factor V activating enzyme), vascular endothelial growth factor (VEGF, 4.3%), snake venom metalloproteinase (SVMP, 2.5%, mainly Factor X activating enzyme) and phosphodiesterase (PDE, 2.5%). Other minor proteins include cysteine-rich secretory protein (CRiSP), snake venom C-type lectin/lectin-like protein (snaclec), nerve growth factor, L-amino acid oxidase and 5′-nucleotidase. PLA2, KSPI, SVSP, snaclec and SVMP are hemotoxic proteins in the venom. The study indicated substantial venom variation in D. russelii venoms of different locales, including 3 Pakistani specimens kept in the USA. The venom exhibited potent procoagulant activity on human plasma (minimum clotting dose = 14.5 ng/ml) and high lethality (rodent LD50 = 0.19 μg/g) but lacked hemorrhagic effect locally. The Indian VINS Polyvalent Antivenom bound the venom immunologically in a concentration-dependent manner. It moderately neutralized the venom procoagulant and lethal effects (normalized potency against lethality = 2.7 mg venom neutralized per g antivenom). Biological significance: Comprehensive venom proteomes of D. russelii from different locales will facilitate better understanding of the geographical variability of the venom in both qualitative and quantitative terms. This is essential to provide scientific basis for the interpretation of differences in the clinical presentation of Russell's viper envenomation. The study revealed a unique venom proteome of the Pakistani D. russelii from the wild (Indus Delta), in which PLA2 predominated (~60% of total venom proteins). The finding unveiled remarkable differences in the venom compositions between the wild (present study) and the captive specimens reported previously. The integration of toxicity tests enabled the correlation of the venom proteome with the envenoming pathophysiology, where the venom showed potent lethality mediated through coagulopathic activity. The Indian VINS Polyvalent Antivenom (VPAV) showed binding activity toward the venom protein antigens; however the immunorecognition of small proteins and PLA2-dominating fractions was low to moderate. Consistently, the antivenom neutralized the toxicity of the wild Pakistani Russell's viper venom at moderate efficacies. Our results suggest that it may be possible to enhance the Indian antivenom potency against the Pakistani viper venom by the inclusion of venoms from a wider geographical range including that from Pakistan into the immunogen formulation
Wind Induced Response of Spar-mooring-riser System
No full textIn recent decades, the exploitation of hydrocarbon reservoirs under the seas and oceans has been regarded as a viable alternative. Several types of floating structures are utilized in deep and ultra-deep water oil and gas exploration and production. Spar platforms are the most recent type of platforms to be designed and utilized in deep water environments. This type of platform is an assemblage of a cylindrical hull, moorings and risers that responds to hydrodynamic and aerodynamic loads in a complex manner. Coupled behaviours of spar–mooring–riser system influenced by the wind load in random wave environment have been studied using coupled analysis method. The spar–mooring–riser system has been analysed to predict system responses induced by wind action under a long crested random wave using finite element approach. Wind load induces a significant shift in the spar position away from its original place in the random sea state in addition to a notable heave motion reduction. The top tension magnitude of the moorings and riser significantly increased. The diminishing fluctuation highlights the firmness and controlled oscillations of the spar platform relative to its new mean position
Separation of Chlorella biomass from culture medium by flocculation with rice starch
No full textCoagulation-flocculation remains as one of the preferred methods for efficient harvesting of Chlorella sp. cells. Although the use of established aluminium salts is highly appraised for high harvesting efficiencies, excessive residual aluminium imparted on both the treated supernatant and harvested biomass remained worrisome. Hence, the objective of this present study is to minimize the resulting concentration of aluminium present in the system by evaluating the use of rice starch as an aid to chemical coagulants. The residual aluminium in the starch aided and non-aided treated supernatants and biomass were then determined by using an inductively coupled plasma-optical emission spectroscopy (ICP-OES) and energy-dispersive X-ray (EDX) spectroscopy respectively. At an optimum pH of 6, more than 95% of the initial Chlorella biomass was recovered at 72 mg/L of alum or 9 mg/L of PACl. However, high residual aluminium contents in treated supernatants (1.3–1.7 mg/L) and biomass (2.5–4.5% weight distribution) were evident. Through the introduction of autoclaved rice starch by up to 120 mg/L as an aid, the dosage of chemical coagulants applied and the detected residual aluminium concentrations were reduced by up to 54%. Despite the increment in organic loadings for these treated samples, the use of starch which is biodegradable would minimize the resulting toxicity and metal contamination imparted. Thus, rice starch can be considered as a potential alternative to lower the dependence on chemical coagulants which limits the reusability of culture medium. Based on the FE-SEM micrographs obtained, the resulting flocs treated with rice starch were notably filamentous and threadlike; in-line with the coagulation mechanism of adsorption and bridging
Effect of Temperature on the Physical, Electro-Chemical and Adsorption Properties of Carbon Micro-Spheres Using Hydrothermal Carbonization Process
No full textrch deals with the effect of the temperature on the physical, thermal, electrochemical, and adsorption properties of the carbon micro-spheres using hydrothermal carbonization (HTC). Until recently, limited research has been conducted regarding the effects of delignification during the HTC process of biomass residues especially Dimocarpus longan. In this regard, lignin was first extracted from the lingo-cellulosic waste of Longan fruit peel (Dimocarpus longan). The holocellulose (HC) separated from lignin and raw biomass substrates (Longan fruit exocarp/peel powder, LFP) were carbonized at different temperatures using water as the green catalyst. Hydrothermal carbonization (HTC) was performed for both of the samples (LFP and HC) at 200°C, 250°C, and 300°C for 24 h each. The surface morphological structures, the porosity, and the Brunauer-Emmett-Teller (BET) surface area of the prepared micro-spherical carbon were determined. The BET surface areas obtained for HC-based carbon samples were lower than that of the raw LFP based carbon samples. The carbon obtained was characterized using ultimate and proximate analyses. The surface morphological features and phase transformation of the synthesized micro-spherical carbon was characterized by a field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analysis. The results demonstrated that the extraction of lignin could significantly alter the end properties of the synthesized carbon sample. The carbon spheres derived from LFP showed a higher carbon content than the HC-based carbon. The absence of lignin in the holo-cellulose (HC) made it easy to disintegrate in comparison to the raw, LFP-based carbon samples during the HTC process. The carbonaceous samples (LFP-300 and HC-300) prepared at 300°C were selected and their adsorption performance for Pb (II) cations was observed using Langmuir, Freundlich, and Temkin linear isotherm models. At 30°C, the equilibrium data followed the Langmuir isotherm model more than the Freundlich and Temkin model for both the LFP-300 sample and the HC-300 sample. The potential of the synthesized carbon microspheres were further analyzed by thermodynamic characterizations of the adsorption equilibrium system
Micro-money, finance and real economy interrelationship in the framework of Islamic ontology of unity of knowledge and the world-system of social economy
No full textPurpose – The purpose of this paper is to explain the structure of Islamic monetary transformation into 100 percent reserve requirement monetary system in terms of the foundational epistemology of the unity of divine knowledge (tawhid). This approach is a scholarly originality in the field of epistemological formalism concerning Islamic theory and perspectives in economic reasoning in comparative perspectives. Design/methodology/approach – The role of micro-money pursuing projects and real economic exchange relations is shown to arise by a natural causality in the ethical social economy (SE). This results in a microeconomic perspective of the quantity theory of money with ethical and social implications. A comparative study of endogenous money in the quantity theory of money points out significant differences between the theory of endogenous money in Islam and mainstream methodologies. A formal model of micro-money and its organismic endogenous relationship with the real economy is formulated with the goal of realizing social well-being, economic stabilization, and sustainability of development regimes. Findings – This is a conceptual paper, though with the potential for continued work in applying the theory of micro-money in the Islamic methodological perspective of unity of knowledge. This is an original contribution of this paper. Islamic economists have not been able to produce a rigorous theory of micro-money. They have also not been able to situate the study of Islamic economics with its specific contribution to the field of the nature of money in project-specific financing of Islamic projects by the money-finance-real economy inter-causal relations. Thus, the findings of this paper, though of the conceptual nature, open doors to a vast field of methodological development and its application to the problem of micro-money modeling. Such a conceptual finding arising from the methodological theory of unity of knowledge and applied to the topic of micro-money along with some examples of potentiality of these approaches constitutes a vastly original field of findings as contribution. Thereby, an analytical model is established in the Islamic social economy (ISE) perspective. The model is used to explain monetary transmission and functioning of monetary policy with instruments that avoid interest rate and comply with Islamic financing requirements. The resulting model of money, finance, and real economy (MFE) systemic interrelationship in reference to the epistemology of unity of knowledge leads into the construction of a 100 percent reserve requirement monetary system with the gold-backed micro-money as currency complementing real economic transactions. Research limitations/implications – The present paper is of a conceptual type based on the essential ontological and epistemological foundation of Islamic social and economic thought and bearing a deeply scientific implication. The conceptual part of this paper becomes a study in the foundations. The second part follows into the study of application in the real world of micro-money in terms of financing projects. Micro-money pursues projects in the Islamic economy due to its very nature of ethical and social choices. The paper shows that such a micro-money transmission is realized by the money-finance-real economy integrated model. Thereby, some real-world examples of such transformations are given. All these together substantiate the conceptual-analytical-empirical nature of the study conducted. Practical implications – The development of the micro-money transmission system of generalized circular causation interrelations between MFE activities as a return to 100 percent reserve requirement monetary system with the gold standard is the profound theory that has been propounded. Its applied perspectives are implied through the MFE-model wherein micro-money pursues social projects. Furthermore, the possibility and practicality of such a conceptual model of micro-money and its transmission mechanism in the real economy are established by real-world examples of kinds of micro-money that are found to circulate or are recommended by some studies in the literature. Social implications – The conceptual part of the paper presents a model of generalized epistemological model of unity of knowledge characterizing the MFE circular causal interrelations as the organismic meaning of social ethics and evolutionary learning. The social implications are the epistemic foundations of the derived model in the midst of choices of life-fulfillment projects that micro-money finances and the economy sustain. Originality/value – This is an original paper premised on the general and the specific Islamic epistemological criterion of unity of knowledge as a generalized system theory. It is now particularized to the case of money and real economy by using the Islamic perspective of creating conditions to regenerate resources continuously in SE with ethical implications. The paper is equally informative to all who like to understand the social and ethical nature of endogenous relations between money and the real economy as two great institutions of the national economy. These together bestow well-being to the society at large in the construction of SE. Specific attention in this regard is given to ISE
Statistical Analysis Towards Improvement of Design Rainfall: Case Study of Peninsular Malaysia
No full textThe main focus of this study is to find a better approach for the improvement of rainfall intensity–duration–frequency (IDF) for Peninsular Malaysia by fitting the best statistical model to each data series. This is because IDF curve is generally used to determine the design rainfall in designing water resource structures. Data are collected from 60 selected rainfall stations in Peninsular Malaysia based on their completeness of data and coverage area. Two models are chosen and compared to derive the IDF relationship, which are fitting PDS to generalized Pareto (GPA) distribution (GPA/PDS) and fitting AMS to generalized extreme value (GEV) distribution (GEV/AMS). Based on the L-moment ratio diagram, it is found that the model based on fitting PDS to GPA distribution is more suitable in derivation of rainfall IDF relationship in Peninsular Malaysia. A software package containing Rain Event Mining Tool (RainEMT), Rain IDF and RainMap is developed to aid the study
Prevalence, Antimicrobial Resistance, and Genetic Diversity of Listeria spp. Isolated from Raw Chicken Meat and Chicken-Related Products in Malaysia
No full textListeria spp. are ubiquitous in nature and can be found in various environmental niches such as soil, sewage, river water, plants, and foods, but the most frequently isolated species are Listeria monocytogenes and Listeria innocua. In this study, the presence of Listeria spp. in raw chicken meat and chicken-related products sold in local markets in Klang Valley, Malaysia was investigated. A total of 44 Listeria strains (42 L. innocua and 2 L. welshimeri) were isolated from 106 samples. Antibiotic susceptibility tests of the L. innocua strains revealed a high prevalence of resistance to clindamycin (92.9%), ceftriaxone (76.2%), ampicillin (73.8%), tetracycline (69%), and penicillin G (66.7%). Overall, 31 L. innocua and 1 L. welshimeri strain were multidrug resistant, i.e., nonsusceptible to at least one antimicrobial agent in three or more antibiotic classes. The majority of the L. innocua strains were placed into five AscI pulsogroups, and overall 26 distinct AscI pulsotypes were identified. The detection of multidrug-resistant Listeria strains from different food sources and locations warrants attention because these strains could serve as reservoirs for antimicrobial resistance genes and may facilitate the spread and emergence of other drug-resistant strains
Food waste compost as an organic nutrient source for the cultivation of Chlorella vulgaris
No full textThe present study investigates the prospective of substituting inorganic medium with organic food waste compost medium as a nutrient supplement for the cultivation of Chlorella vulgaris FSP-E. Various percentages of compost mixtures were replaced in the inorganic medium to compare the algal growth and biochemical composition. The use of 25% compost mixture combination was found to yield higher biomass concentration (11.1%) and better lipid (10.1%) and protein (2.0%) content compared with microalgae cultivation in fully inorganic medium. These results exhibited the potential of combining the inorganic medium with organic food waste compost medium as an effective way to reduce the cultivation cost of microalgae and to increase the biochemical content in the cultivated microalgae