Search results for: disease-carrying organisms

Authors: Jeter Canete, Noreen Joyce Estrella, Yedda Sachi Patrice Madelo

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Zooplankton plays a crucial role in aquatic ecosystems and a number of water parameters involved in it. Despite their relevance, there is inadequate information about zooplankton communities in Sarangani Bay, Sarangani Province: one of the most essential waterbodies in Mindanao. The aim of the present study was to determine the composition, abundance, and diversity of zooplankton as well as to provide more recent data about the physico-chemical characteristics of Sarangani Bay. Zooplankton samples were collected by vertical hauls using a zooplankton net (mouth diameter: 0.5m; mesh size opening: round, 350μm) in three stations in the coastal waters of Alabel, Malapatan, and Maasim during November 2018. A total of 74 species of zooplankton belonging mainly to Kingdom Protozoa, Phylum Arthropoda, Chaetognatha, and Chordata were identified. Results showed a total zooplankton abundance of 1,984,166 ind/m³ with the highest count recorded at Malapatan (717,169 ind/m³) and the lowest at Maasim (624,411 ind/m³). Among 22 zooplankton groups identified, subclass Copepoda was found to be the most dominant (73.10%), followed by Appendicularia (12.18%) and Vertebrata (3.54%). Diversity analysis revealed an even distribution of species and a diverse ecosystem in all stations sampled. Correlation analysis indicated a strong relationship between zooplankton abundance and physico-chemical parameters. Overall, the physico-chemical profile of Sarangani Bay did not differ from the standards set by DENR, and analysis of the zooplankton communities revealed that Sarangani Bay favorably supports marine organisms to flourish. The findings of this study provide useful knowledge on zooplankton communities and can be used to create management strategies to protect the aquatic biodiversity in Sarangani Bay.

Keywords: aquatic biomonitoring, biodiversity, physicochemical analysis, population survey, Sarangani Bay, Sarangani Province, zooplankton

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Authors: Oluwatosin Adetola Arojojoye, Olajumoke Olufunlayo Alao, Philip Odigili

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This study investigated the extent of pollution in Eleyele River in Oyo State, Nigeria by investigating the antioxidant status and malondialdehyde levels (index of lipid peroxidation) in the organs of African Catfish, Clarias gariepinus from the river. Clarias gariepinus weighing between 250g-400g were collected from Eleyele River (a suspected polluted river) and Clarias gariepinus from a clean fish farm (Durantee fisheries) were used as the control. Levels of malondialdehyde, glutathione concentration (GSH) and activities of antioxidant enzymes - superoxide dismutase, catalase and glutathione-S-transferase (GST) were evaluated in the post-mitochondrial fractions of the liver, kidney and gills of the fishes. From the results, there were increases in malondialdehyde level and GSH concentration in the liver, kidney and gills of Clarias gariepinus from Eleyele River when compared with control. Glutathione-S-transferase activity was induced in the liver and kidney of Clarias gariepinus from Eleyele River when compared with control. However, the activity of this enzyme was depleted in the gills of fishes from Eleyele River compared with control. Also there was an induction in SOD activity in the liver of Clarias gariepinus from Eleyele River when compared with control but there was a decrease in the activity of this enzyme in the kidney and gills of fishes from Eleyele River compared with control. Increase in lipid peroxidation and alterations in antioxidant system in Clarias gariepinus from Eleyele River show that the fishes were under oxidative stress. These suggest that the river is polluted probably as a result of industrial, domestic and agricultural wastes frequently discharged into the river. This could pose serious health risks to consumers of water and aquatic organisms from the river.

Keywords: antioxidant, lipid peroxidation, Clarias gariepinus, Eleyele River

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Authors: Aida Mammadova, Juan Pastor Ivars

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Japanese gardens can be considered as the unique hubs to preserve urban biodiversity, as they provide the habitat for the diverse network of living organisms, facilitating to the movement of the rare species around the urban landscape, became the refuge for the moss and many endangered species. For the centuries, Japanese gardens were considered as ecologically sustainable and well-organized ecosystems, due to the skilled maintenances and management. However, unfortunately, due to the depopulations and ageing in Japanese societies, gardens are becoming more abandoned, and there is an urgent need to increase the awareness about the importance of the Japanese gardens to preserve the urban biodiversity. In this study, we have conducted the participatory educational field trips for 12 students into the to the five gardens protected by Kanazawa City and learned about the preservation activities conducted at the governmental, municipal, and local levels. After the courses, students have found a strong linkage between the gardens with the traditional culture. Kanazawa City, for more than 400 years is famous with traditional craft makings and tea ceremonies, and it was noticed that the cultural diversity of the city was strongly supported by the biodiversity of the gardens, and loss of the gardens would bring to the loss of the traditional culture. Using the experiential approach during the fieldworks, it was observed by the students that the linkage between the bio-cultural diversity strongly depends on humans’ activities. The continuous management and maintenance of the gardens are the contributing factor for the preservation of urban diversity. However, garden management is very time and capital consuming process, and it was also noticed that there is a big need to attract all levels of the society to preserve the urban biodiversity through the participatory urbanism.

Keywords: biodiversity, conservation, educational fieldwork, Japanese gardens

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Authors: Rajani Kant Rai, Jayakrishnan Athipet

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There have been several attempts to prepare polymers with antimicrobial properties by doping with various N-halamines. Hydantoins (Cyclic N-halamine) is of importance due to their stability rechargeable chloroamide function, broad-spectrum anti-microbial action and ability to prevent resistance to the organisms. Polymerizable hydantoins are synthesized by tethering vinyl moieties to 5,5,-dialkyl hydantoin sacrificing the imide hydrogen in the molecule thereby restricting the halogen capture only to the amide nitrogen that results in compromised antibacterial activity. In order to increase the activity of the antimicrobial polymer, we have developed a scheme to maximize the attachment of chlorine to the amide and the imide moieties of hydantoin. Vinyl hydantoin monomer, (Z)-5-(4-((3-methylbuta-1,3-dien-2-yl)oxy)benzylidene)imidazolidine-2,4-dione (MBBID) was synthesized and copolymerized with a commercially available monomer, methyl methacrylate, by free radical polymerization. The antimicrobial activity of hydantoin is strongly dependent on their surface area and hence their microbial activity increases when incorporated in microspheres or nanoparticles as compared to their bulk counterpart. In this regard, smooth and rough surface microsphere of the vinyl monomer (MBBID) with commercial monomer was synthesized. The oxidative chlorine content of the copolymer ranged from 1.5 to 2.45 %. Further, to demonstrate the water purification potential, the thin column was packed with smooth or rough microspheres and challenged with simulated contaminated water that exhibited 6 log kill (total kill) of the bacteria in 20 minutes of exposure with smooth (25 mg/ml) and rough microsphere (15.0 mg/ml).

Keywords: cyclic N-halamine, vinyl hydantoin monomer, rough surface microsphere, simulated contaminated water

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Authors: Aroma Elmina Martha

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Environment affects the continuity of life and human well-being and the bodies of other living. Environmental quality is very closely related to the quality of life. Sustainability must be protected from damage due to the use of natural resources, such as tin mining in Bangka island. This research is a descriptive study, which identifies the environmental damage caused by mining land and sea in Bangka district. The approach used is juridical, social and economic. The study uses primary legal materials, secondary, and tertiary, equipped with field research. The analysis technique used is qualitative analysis. The impacts of mining on land among other physical and chemical damage, erosion and widening the depth of the river, a pool of micro-climate, the quality and feasibility, vegetation, wildlife and biodiversity, land values, social and economic. This mining causes damage to the soil structure, and puddles in the former digs which were not backfilled again. The impact of mining on the ocean such as changes in current surge, erosion and abrasion basic coastal waters, shoreline change, marine water quality changes, and changes in marine communities. The findings of the research show that tin mining in the sea also potentially have a significant impact on the life of the reef, populations of marine organisms. However, mining on land needs to consider the impact of the damage, so that the damage can be minimized. In the recovery process needs to be pursued by exploiting the rest of the pile of tin. Thus, mining activities should take into account the distance of beach sediment size, wave height, wave length, wave period, and the acceleration of gravity. The process of the tin washing should be done in a fairly safe area, thus avoiding damage to the coral reefs that will eventually reduce the population of marine life.

Keywords: abration, environmental damage, mining, shoreline

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Authors: Syazwani Idrus, Charles Banks, Sonia Heaven

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The effect of osmotic stress was carried out to determine the ability for biogas production in two types of digesters; anaerobic sludge blanket and anaerobic filters in treating wheat straw washed water. Two anaerobic filters (AF1 and 2) and two UASB reactors (U1 and 2) with working volumes of 1.5 L were employed at mesophilic temperatures (37°C). Digesters AF1 and two were seeded with an inoculum which had previously been fed on with a synthetic wastewater includingSodium Chloride and Potassium Chloride. Digesters U1 and two were seeded with 1 kg wet weight of granular sludge which had previously been treating paper mill effluent. During the first 48 days, all digesters were successfully acclimated with synthetic wastewater (SW) to organic loading rate (OLR) of 6 g COD l^-1 day-1. Specific methane production (SMP) of 0.333 l CH4 g-1 COD). The feed was then changed to wash water from a washing operation to reduce the salt content of wheat straw (wheat straw wash water, WSW) at the same OLR. SMP fell sharply in all reactors to less than 0.1 l CH4 g^-1 COD, with the AF affected more than the UASB. The OLR was reduced to 2.5 g COD l^-1 day^-1 to allow adaptation to WSW, and both the UASB and the AF reactors achieved an SMP of 0.21 l CH4 g^-1 COD added at 82% of COD removal. This study also revealed the accumulation of potassium (K) inside the UASB granules to a concentration of 4.5 mg K g^-1 wet weight of granular sludge. The phenomenon of lower SMP and accumulation of K indicates the effect of osmotic stress when fed on WSW. This finding is consistent with the theory that methanogenic organisms operate a Potassium pump to maintain ionic equilibrium, and as this is an energy-driven process, it will, therefore, reduce the overall methane yield.

Keywords: wheat straw wash water, upflow anaerobic sludge blanket, anaerobic filter, specific methane production, osmotic stress

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Authors: Nitin Pipralia, Amit Kmar Sinha, Gudrun de Boeck

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Atmospheric carbon dioxide (CO2) concentrations have been increasing since the beginning of the industrial revolution due to combustion of fossils fuel and many anthropogenic means. As the number of scenarios assembled by the International Panel on Climate Change (IPCC) predict a rise of pCO2 from today’s 380 μatm to approximately 900 μatm until the year 2100 and a further rise of up to 1900 μatm by the year 2300. A rise in pCO2 results in more dissolution in ocean surface water which lead to cange in water pH, This phenomena of decrease in ocean pH due to increase on pCO2 is ocean acidification is considered a potential threat to the marine ecosystems and expected to affect fish as well as calcerious organisms. The situation may get worste when the stress of salinity adds on, due to migratory movement of fishes, where fish moves to different salinity region for various specific activities likes spawning and other. Therefore, to understand the interactive impact of these whole range of two important environmental abiotic stresses (viz. pCO2 ranging from 380 μatm, 900 μatm and 1900 μatm, along with salinity gradients of 32ppt, 10 ppt and 2.5ppt) on the ecophysiologal performance of fish, we investigated various biological adaptive response in European sea bass (Dicentrarchus labrax), a model estuarine teleost. Overall, we hypothesize that effect of ocean acidification would be exacerbate with shift in ambient salinity. Oxygen consumption, ammonia metabolism, iono-osmoregulation, energy budget, ion-regulatory enzymes, hormones and pH amendments in plasma were assayed as the potential indices of compensatory responses.

Keywords: ocean acidification, sea bass, pH climate change, salinity

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Authors: Masoud Sheidai

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Biologists with a special field of population genetics and phylogeny have different research tasks such as populations’ genetic variability and divergence, species relatedness, the evolution of genetic and morphological characters, and identification of DNA SNPs with adaptive potential. To tackle these problems and reach a concise conclusion, they must use the proper and efficient statistical and bioinformatic methods as well as suitable genetic and morphological characteristics. In recent years application of different bioinformatic and statistical methods, which are based on various well-documented assumptions, are the proper analytical tools in the hands of researchers. The species delineation is usually carried out with the use of different clustering methods like K-means clustering based on proper distance measures according to the studied features of organisms. A well-defined species are assumed to be separated from the other taxa by molecular barcodes. The species relationships are studied by using molecular markers, which are analyzed by different analytical methods like multidimensional scaling (MDS) and principal coordinate analysis (PCoA). The species population structuring and genetic divergence are usually investigated by PCoA and PCA methods and a network diagram. These are based on bootstrapping of data. The Association of different genes and DNA sequences to ecological and geographical variables is determined by LFMM (Latent factor mixed model) and redundancy analysis (RDA), which are based on Bayesian and distance methods. Molecular and morphological differentiating characters in the studied species may be identified by linear discriminant analysis (DA) and discriminant analysis of principal components (DAPC). We shall illustrate these methods and related conclusions by giving examples from different edible and medicinal plant species.

Keywords: GWAS analysis, K-Means clustering, LFMM, multidimensional scaling, redundancy analysis

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Authors: Sidra Shaheen, Nadir Naveed Siddiqui, Shah Ali Ul Qader

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In recent years, significant progress has been made in discovering and developing new bacterial polysaccharides producing organisms possessing extremely functional properties. Levan is a natural biopolymer of fructose which is produced by transfructosylation reaction in the presence of levansucrase. It is one of the industrially promising enzymes that offer a variety of industrial applications in the field of cosmetics, foods and pharmaceuticals. Although levan has significant applications but the yield of levan produced is not equal to other biopolymers due to the inefficiency of producer microorganism. Among wide range of levansucrase producing microorganisms, Zymomonas mobilis is considered as a potential candidate for large scale production of this natural polysaccharide. The present investigation is concerned with the isolation of levansucrase producing natural isolate having maximum enzyme production. Furthermore, production parameters were optimized to get higher enzyme yield. Levansucrase was partially purified and characterized to study its applicability on industrial scale. The results of this study revealed that the bacterial strain Z. mobilis KIBGE-IB14 was the best producer of levansucrase. Bacterial growth and enzyme production was greatly influenced by physical and chemical parameters. Maximum levansucrase production was achieved after 24 hours of fermentation at 30°C using modified medium of pH-6.5. Contrary to other levansucrases, the one presented in the current study is able to produce high amount of products in relatively short period of time with optimum temperature at 35°C. Due to these advantages, this enzyme can be used on large scale for commercial production of levan and other important metabolites.

Keywords: levansucrase, metabolites, polysaccharides, transfructosylation

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Authors: Ines Kovacic, Dijana Pavicic-Hamer, Petra Buric, Maja Levak Zorinc, Daniel M. Lyons

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Silver nanoparticles (AgNPs), owing to their unique physical and chemical properties, have become one of the most widely used nanoparticles in consumer products. Despite the increased use of AgNPs in science and industry over the past twenty years, only relatively recently has concern been raised over their entering brackish and marine environments. However, data on their potential impact on marine organisms, especially invertebrates are very limited. This study aimed to examine the effects of 60 nm AgNPs (10, 100, 500 and 1000 µg/l) and silver ions (100, 1000 µg/l) on the Mediterranean green crab Carcinus aestuarii Nardo, 1847. The crab mortality was assessed during seven days of exposure. After the exposure, total haemocytes (THC) and differential haemocytes number (DHC) were counted (immune response), in addition to histological examination of gills stained with haematoxylin and eosin. The effect of AgNPs and silver ions resulted in a dose dependent mortality and destruction of gills epithelium with haemocytes infiltration in the gills lacuna. Total haemocyte count was greater with increasing concentration of AgNPs, at concentrations from 10 to 500 µg/l. Hyalinocytes were the most common immunological cells noted in the crab hemolymph, while granulocytes and semigranulocytes were suppressed with increasing concentration of AgNPs (500 and 1000 µg/l). Thus, as crabs are filter feeders, they are susceptible to uptake of AgNPs by direct accumulation in gills mucus or indirectly via circulation of haemocytes in their open vascular system. Results of this study on crabs add to knowledge of the effects of AgNPs in the marine environment.

Keywords: crab, immune response, histological alteration, silver nanoparticles

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Authors: Elvira Hörandl

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The term “Geographical parthenogenesis” describes the phenomenon that asexual organisms usually occupy larger and more northern distribution areas than their sexual relatives and tend to colonize previously glaciated areas. Several case studies in flowering plants confirm the geographical pattern, but the causal factors behind the phenomenon are still unclear. Previous authors regarded predominant polyploidy in asexual (apomictic) plants as the main factor. However, the geographical pattern is not the rule for sexual polyploids. Recent research confirmed a previous hypothesis of the author that a combination of factors is acting: Although uniparental reproduction provides better colonization abilities, it is most efficient in combination with polyploidy. I will present results on case studies in the genus Ranunculus of both autopolyploid and allopolyploid species and species complexes reproducing via facultative apomixis. Polyploidy seems to contribute mainly to a better tolerance of colder climates and temperate extremes, whereby epigenetic flexibility, changes in gene expression, and phenotypic plasticity play an important role in occupying ecological niches under harsh conditions. Phylogenomic studies entangle complex hybrid origins of asexual taxa, which increases intragenomic heterozygosity of asexual plants. Interestingly, our results suggest an association of sexuality with abiotic stresses, specifically with light stress, which might explain that still, most plants in high altitudes and in southern areas retain sexual reproduction despite other climatic conditions that would favor apomictic plants. We conclude that geographical parthenogenesis results from the complex interplay of the genomic constitution, mode of reproduction and environmental factors.

Keywords: apomixis, polyploidy, hybridization, abiotic stress, epigenetics, phylogenomics

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Authors: Lemar Blake, Chris Oura, Ayanna C. N. Phillips Savage

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Improved DNA sequencing technology has greatly enhanced bacterial identification, especially for organisms that are difficult to culture. Mycobacteriosis with consistent hyphema, bilateral exophthalmia, open mouth gape and ocular lesions, were observed in various fish populations at the School of Veterinary Medicine, Aquaculture/Aquatic Animal Health Unit. Objective: To identify the species of Mycobacterium that is affecting aquarium fish at the School of Veterinary Medicine, Aquaculture/Aquatic Animal Health Unit. Method: A total of 13 fish samples were collected and analyzed via: Ziehl-Neelsen, conventional polymerase chain reaction (PCR) and real-time PCR. These tests were carried out simultaneously for confirmation. The following combination of conventional primers: 16s rRNA (564 bp), rpoB (396 bp), sod (408 bp) were used. Concatenation of the gene fragments was carried out to phylogenetically classify the organism. Results: Acid fast non-branching bacilli were detected in all samples from homogenized internal organs. All 13 acid fast samples were positive for Mycobacterium via real-time PCR. Partial gene sequences using all three primer sets were obtained from two samples and demonstrated a novel strain. A strain 99% related to Mycobacterium marinum was also confirmed in one sample, using 16srRNA and rpoB genes. The two novel strains were clustered with the rapid growers and strains that are known to affect humans. Conclusions: Phylogenetic analysis demonstrated two novel Mycobacterium strains with the potential of being zoonotic and one strain 99% related to Mycobacterium marinum.

Keywords: polymerase chain reaction, phylogenetic, DNA sequencing, zoonotic

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Authors: Bandi Aruna

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The increase of multidrug-resistant pathogens and the restriction on the use of antibiotics due to its side effects have drawn attention to the search for possible alternatives. Bacteriocins are ribosomally synthesized antimicrobial peptides that are active against Gram-positive and Gram-negative bacteria. The bacteriocins from lactic acid bacteria represent an important application of these peptides as clinical drugs or as food biopreservatives. The present study describes the isolation of bacteriocin producing lactic acid bacteria (LAB) from fermented batter of green gram and bengal gram using Man, Rogosa and Sharpe (MRS) media. The bacteriocin produced by these organisms inhibited the growth of Staphylococcus aureus, Escherichia coli, Klebsiella species, Pseudomonas aeruginosa, The isolates G1, G2 were isolated from green gram; B1 and B2 were isolated from fermented bengal gram batter. G1 and G2 were identified as Lactobacillus casie and B1 and B2 were identified as Streptococcus species. Antimicrobial activity of the bacteriocin produced by these strains was studied by agar well diffusion method. Bacteriocins produced by the Lactobacillus casie and Streptococcus secies retained their antagonistic property at pH of 5 and pH of 7. Exposure of bacteriocin to UV light for 4 min showed antibacterial activity. The antagonistic property was observed even at 100°C demonstrating stability at higher temperatures of the bacteriocin. The bacteriocins were stable for a period of 15 days at 27°C. The bacteriocins of G1, G2, and B2 exhibited highest antagonistic activity at pH of 5 and B1 at pH of 7. Therefore, the bacteriocins of the isolates may find important application in controlling the food-borne pathogens.

Keywords: Keywords: Antibacterial activity, Lactic acid bacteria, Bacteriocin

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Authors: Elif Coskun Daggecen, Seyma Dokucu, Yekta Gezginc, Ismail Akyol

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Fermented dairy food quality is mainly determined by the sensory perception and influenced by many factors. Today, starter cultures for fermented foods are being developed to have a constant quality in these foods. Streptococcus thermophilus is one of the main species of most a starter cultures of yogurt fermentation. This species produces lactate by lactose fermentation from pyruvate. On the other hand, a small amount of pyruvate can alternatively be converted to various typical yoghurt flavor compounds such as diacetyl, acetoin, acetaldehyde, or acetic acid, for which the activity of three genes are shown to be especially important; ldh, nox and als. Up to date, commercially produced yoghurts have not yet met the desired aromatic properties that Turkish consumers find in traditional homemade yoghurts. Therefore, it is important to select starters carrying favorable metabolic characteristics from natural isolates. In this study, 30 strains of Str. Thermophilus were isolated from traditional Turkish yoghurts obtained from different regions of the country. In these strains, transcriptional levels of ldh, nox and als genes were determined via a newly developed qPCR protocol, which is a more reliable and precision method for analyzing the quantitative and qualitative expression of specific genes in different experimental conditions or in different organisms compared to conventional analytical methods. Additionally, the metabolite production potentials of the isolates were measured. Of all the strains examined, 60% were found to carry the metabolite production potential and the gene activity which appeared to be suitable to be used as a starter culture. Probable starter cultures were determined according to real-time PCR results.

Keywords: gene expression, RT-PCR, starter culture, Streptococcus thermophilus

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Authors: Asimiyu Mohammed Jinadu

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Housing is a basic necessity of life. Housing plays a central role in the life of living organisms as it provides the basic platform for the life support systems in human settlements. It is considered a social service and a basic right. Despite the importance of housing, Nigeria as a nation is faced with the problem of quantitative and qualitative shortfall in the number of housing units required to accommodate the citizens. This study examined the accessibility and affordability problems of low-income housing in Nigeria. It relied on secondary data obtained for the records of government ministries and agencies. Descriptive statistics were used in the analysis, and the information was presented in simple tables and charts. The findings show that over the years the government has provided serviced plots of land, owner occupier houses and mortgage loans for the people. As at 2016, the Federal Housing Authority (FHA) has completed a total of 23,038 housing units while another 14, 488 units were on-going under the Public Private Partnership scheme across the country. The study revealed that a total of 910, 671 housing units were proposed by the Government under the various low-income housing programmes between 1960 and 2017, but only 156, 336 units were delivered within the period, representing 17.17% success rate. Amongst others, the low-income group faced the problems of low access to and unaffordability of the few low-income housing delivered in Nigeria. The study recommended that all abandoned housing projects should be reviewed, rationalized, completed and made available to the targeted low-income people. Investment in micro housing finance, design and implementation of pro-poor housing programme and massive investment in innovative slum upgrading programmes by both the government and private sector are also recommended to ameliorate the housing problems of the low-income group in Nigeria.

Keywords: housing, low income group, problem, programme

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Authors: Ghadah Abusalim, Suliman Alharbi, Hesham Khalil, Milton Wainwright, Mohammad A. Khiyami

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The use of implantable foreign devices in medicine has recently increased dramatically. Intravascular cannulae and catheters are used to administer fluids, medications, parenteral nutrition, and blood products in order to monitor hemodynamic status and also to provide hemodialysis. The early and late failure of inserted or implanted devices is largely the result of bacterial infection and may lead to the disruption of integration between the device and the tissues which surround it. Staphylococcus aureus and Staphylococcus epidermidis are widely considered to be the most common organisms causing device-related infection. Our study showed that S. aureus and S. epidermidis adhered to intravascular cannulae made up of PTFE, SPTFE and vialon. Adhesion of S. epidermidis and S. aureus to intravascular cannulae varied significantly depending upon the type of material used and the presence of coating materials. Both bacteria adhered less to PTFE followed by Vialon and SPTFE and the adhesion capacity of S. aureus and S. epidermidis increased over time. Coating intravascular cannulae with human serum albumin inhibited the adhesion of S. aureus and S. epidermidis to these cannulae, and pretreatment of cannulae with fibronectin inhibited the adhesion of S. epidermidis but increased the adhesion of S. aureus to all types of cannulae. Pretreatment of cannulae surface with potassium chloride or calcium chloride increased the adhesion of S. aureus and S. epidermidis to cannulae, suggesting a role for electrostatic forces in the mechanism of such adhesion. This study will hopefully clarify the mechanism of adhesion and provide possible means of preventing such adhesion either by the use of better material coatings or by interfering with the process of adhesion by targeting bacterial structures responsible for it. Currently we recommend the use of PTFE cannulae as they exhibit a lower bacterial adhesion capacity compared to the other tested cannulae.

Keywords: Staphylococcus epidermidis, Staphylococcus aureus, adhesion, cannulae, PTFE, Vialon

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Authors: Digby Wrede, Stephen Gray, Syed Hussainy

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Microalgae are extremely useful organisms but notoriously hard to harvest. The use of fungal pellets has been found to be an efficient way to flocculate numerous species of algae. However, only the flocculation of single species of algae has been investigated. Algae are generally found in complex communities in the environment comprising of numerous species of algae ranging from simple single cell algae such as Chlorella to more complex or communal algae such as Dictyosphaerium. This study investigated the flocculation capabilities of Aspergillus oryzae to flocculate four species of algae; Chlorella vulgaris, Scenedesmus quadricauda, Scenedesmus acuminatus and Dictyosphaerium sp., and the algal communities in four different types of domestic effluent from a lagoon-based treatment plant; primary effluent, secondary effluent and the high rate algal pond effluent at a natural and at a lowered pH level. Spectrophotometry was used to measure the changes in algal population. C. vulgaris, S. acuminatus and S. quadricauda, had over 90% reduction of algal in suspension after 24 hours. Dictyosphaerium sp. showed a little to no removal after 24 hours. The primary, secondary, and natural pH level HRAP had roughly a 50% removal after 24 hours, the HRAP which was grown at a lower pH level had over a 90% removal after 24 hours. pH has been shown previously to affect fungal flocculation. Fungal and algae pellets have been shown to be able to treat wastewater and can be converted to biofuels in a very similar method to how algae are currently converted. The mixture of both fungi and algae has also been shown to provide a higher yield of oils then separately and are able to more efficiently treat wastewater then algae or fungi by themselves.

Keywords: algae harvesting, Aspergillus oryzae, fungal flocculation, wastewater treatment

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Authors: Pampita Chakraborty, Sukumar Mukherjee

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The study was done to determine the microbiological profile and changing pattern of the pathogens causing UTI in the ICU patients. All the patients admitted to the ICU with urinary catheter insertion for more than 48hours were included in the study. Urine samples were collected in a sterile container with aseptic precaution using disposable syringe and was processed as per standards. Antimicrobial susceptibility test was done by Disc Diffusion method as per CLSI guidelines. A total of 100 urine samples were collected from ICU patients, out of which 30% showed significant bacterial growth and 7% showed growth of candida spp. Prevalence of UTI was more in female (73%) than male (27.%). Gram-negative bacilli 26(86.67%) were more common in our study followed by gram-positive cocci 4(13.33%). The most common uropathogens isolated were Escherichia coli 14 (46.67%), followed by Klebsiella spp 7(23.33%), Staphylococcus aureus 4(13.33%), Acinetobacter spp 3(10%), Enterococcus faecalis 1(3.33%) and Pseudomonas aeruginosa 1(3.33%). Most of the Gram-negative bacilli were sensitive to amikacin (80%) and nitrofurantoin (80%), where as all gram-positive organisms were sensitive to Vancomycin. A large number ESBL producers were also observed in this study. The study finding showed that E.coli is the predominant pathogen and has increasing resistance pattern to the commonly used antibiotics. The study proposes that the adherence to antibiotic policy is the key ingredients for successful outcome in ICU patients and also emphasizes that repeated evaluation of microbial characteristics and continuous surveillance of resistant bacteria is required for selection of appropriate antibiotic therapy.

Keywords: antimicrobial sensitivity, intensive care unit, nosocomial infection, urinary tract infection

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Authors: Jovana M. Ćirković, Aleksandar M. Radojković, Sanja Z. Perać, Jelena N. Jovanović, Zorica M. Branković, Slobodan D. Milanović, Ivan Lj. Milenković, Jovan N. Dobrosavljević, Nemanja V. Simović, Vanja M. Tadić, Ana R. Žugić, Goran O. Branković

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The protection of forests is a national interest and of strategic importance in every country. The spongy moth (Lymantria dispar) is a damaging invasive pest that can weaken and destroy trees by defoliating them. Chemical pesticides commonly used to protect forests against spongy moths not only have a negative impact on terrestrial and aquatic organisms/ecosystems but also often fail to provide significant protection. Therefore, many eco-friendly alternatives have been considered. Within this research, a new biopesticide was developed based on the method of nanoencapsulation of plant extracts in a biopolymer matrix, which provides a slow release of the active components during a substantial time period. The antifeedant activity of plant extracts of common (Fraxinus excelsior L.), manna (F. ornus L.) ash tree, and the tree of heaven Ailanthus altissima (Mill.) was tested on the spongy moth (Lymantria dispar L, 1758) larvae. To test the antifeedant activity of these compounds, the choice and non-choice tests in laboratory conditions for different plant extract concentrations (0.01, 0.1, 0.5, and 1 % v/v) were carried out. In both cases, the best results showed formulations based on the tree of heaven and common ash for the concentration of 1%, with deterioration indices of 163 and 132, respectively. The main benefit of these formulations is their versatility, effectiveness, prolonged effect, and because they are completely environmentally acceptable. Therefore, they can be considered for suppression of the spongy moth in forest ecosystems.

Keywords: Ailanthus altissima (Mill.), Fraxinus excelsior L., encapsulation, Lymantria dispar

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Authors: Shafaqat Ali, Rehan Ahmad, Muhammad Rizwan

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Chromium (Cr) is one of the most toxic pollutants among heavy metals that adversely affect living organisms and physiological processes in plants. The present study investigated the effect of without and with 15 mg L-1 5-Aminolevulinic acid (ALA) on morpho-physiological attributes of cauliflower (Brassica oleracea botrytis L.) under different Cr concentrations (0, 10, 100 and 200 μM) in the growth medium. Results showed that Cr stress decreased the plant growth, biomass, photosynthetic pigments, and gas exchange characteristics. Chromium stress enhanced the activities of enzymatic antioxidants, catalase (CAT), superoxide dismutase (SOD), and guaiacol peroxidase (POD), and caused oxidative stress, as observed by increased level of malondialdehyde (MDA), hydrogen peroxide (H2O2), electrolyte leakage (EL), in both leaves and roots of cauliflower. Chromium concentrations and total Cr uptake increased in roots, stem and leaves of plants with increasing Cr levels in the growth medium. Foliar application of ALA increased plant growth, biomass, photosynthetic pigments and gas exchange characteristics under Cr stress as compared to without ALA application. As compared to Cr stress alone, ALA application decreased the levels of MDA, H2O2 and EL while further enhanced the activities of antioxidant enzymes in both leaves and roots. Chromium concentrations and total Cr uptake decreased by the ALA application as compared to without ALA. These results showed that foliar application of ALA might be effective in reducing Cr uptake and toxicity in cauliflower.

Keywords: antioxidant enzymes, cauliflower, photosynthesis, chromium, ALA, hydrogen peroxide, electrolyte leakage

Procedia PDF Downloads 272

Authors: Onur Yel

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This study represents the removal of harmful dye substances from wastewaters by using waste and cheap adsorbents. Rapid population growth and industrialization occasion anthropogenic pollution which gives irreversible damage to the environment. One of the ways in which water pollution occurs is caused by the release of the dyestuffs in the textile industry. The release of dyestuffs to the environment directly damages the living creatures that have acquired water habitat. Especially, wastewater cannot be used for nutritional purposes. In addition, some adsorbents have mutagenic and/or carcinogenic effects. By blocking photosynthesis, it hinders the inhibition of photosynthetic bacteria in the water, which damages the ecological balance and also causes the formation of malodorous compounds. Moreover, the lack of oxygen can pose a serious danger to the lives of other living organisms that need oxygen. In recent years, some physical and chemical methods are preferred for the removal of dyestuffs. However, the utilization of these methods is expensive. For this reason, the availability of new and cheap adsorbents becomes the more significant issue. In this study, an investigation of various variables on the removal of Methylene Blue and Acid Red-88 dyestuffs from wastewaters by the usage of pulverized cypress cones has been carried out. Thus, various masses of absorbent (0.1-0.25-0.5-1-2-4-5 grams) are used in 50, 100, 150, 200, 300 ppm concentrations of Methylene Blue and Acid Red-88 dyestuffs’ solutions, and with a variety of the interaction time (0.25-0.5-1-2-4-5 hours). The mixtures were centrifuged and the absorbance of the filtrates was measured on a UV spectrophotometer to determine their remaining concentrations. In the study, the highest removal ratio of Acid Red-88 dyestuff was found to be 81% at 200 ppm of dyestuff with 2 grams of adsorbent at 300 minutes. For Methylene Blue experiments, the removal percentage was found as 98% where 2 grams of adsorbent is used in 200 ppm dyestuff solution at 120 minutes of interaction.

Keywords: acid red-88, biosorption, methylene blue, cypress cones, water pollution

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Authors: Steven Arcidiacono, Robert Stote, Erin Anderson, Molly Richards

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There are numerous standard test methods for antimicrobial textiles that measure activity against specific microorganisms. However, many times these results do not translate to the performance of treated textiles when worn by individuals. Standard test methods apply a single target organism grown under optimal conditions to a textile, then recover the organism to quantitate and determine activity; this does not reflect the actual performance environment that consists of polymicrobial communities in less than optimal conditions or interaction of the textile with the skin substrate. Here we propose the development of in vitro skin model method to bridge the gap between lab testing and wear studies. The model will consist of a defined polymicrobial community of 5-7 commensal microbes simulating the skin microbiome, seeded onto a solid tissue platform to represent the skin. The protocol would entail adding a non-commensal test organism of interest to the defined community and applying a textile sample to the solid substrate. Following incubation, the textile would be removed and the organisms recovered, which would then be quantitated to determine antimicrobial activity. Important parameters to consider include identification and assembly of the defined polymicrobial community, growth conditions to allow the establishment of a stable community, and choice of skin surrogate. This model could answer the following questions: 1) is the treated textile effective against the target organism? 2) How is the defined community affected? And 3) does the textile cause unwanted effects toward the skin simulant? The proposed model would determine activity under conditions comparable to the intended application and provide expanded knowledge relative to current test methods.

Keywords: antimicrobial textiles, defined polymicrobial community, in vitro skin model, skin microbiome

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Authors: Aly Kassem, Eman A. Sabet, Hanaa A. El-Hady, Doha S. Mohamed, Abeer Sheneef, Mona Fattouh, Mamdouh M. Esmat

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Objective: Giardia lamblia parasite is the most common protozoal infection in human. Concomitant Helecobacter Pylori (H. pylori) and Giardia lamblia infection is common for their similar mode of transmission and strong correlation to socioeconomic levels. Only few reports had described gastric giardiasis. Our aim was to detect H. pylori and Giardia in gastric antral mucosal biopsies from patients with dyspepsia. The impact of both pathogens on clinical, endoscopic and histopathogical changes was studied. Methods: 48 patients with dyspepsia (group1) and 28 control patients (patients undergoing esophagogastroduodenoscopy EGD for reasons other than dyspepsia), (group 2) were studied. Endoscopic data were reported and gastric biopsy specimens were obtained for subsequent PCR assay for both organisms and for histopathological and electron microscopic examination. Results: Endoscopic antral gastritis and duodenal lesions were found in both groups, however, they were significantly more frequently in group 1 (p= 0.002 and P= 0.0005 respectively). Esophageal lesions, nodular antral gastritis, gastric ulcers and superficial corpal gastritis were found only in group 1. PCR detected H. pylori infection in 58% Vs 64 % for group 1 and group 2 respectively (P: NS). Giardia infection was present in 67 % Vs 42 % for group 1 and group 2 respectively (P=0.0003, Odd ratio=2.6). Co-infection with H. pylori and Giardia was present in 33% of group 1 Vs 36% for group 2 (P:NS). Abnormal histologic findings were found in both groups, however, intestinal metaplasia was found in group 1 only. Cellular abnormalities in the form of cytoplasmic vacuoles, mitochondrial destruction or nuclear abnormalities were found by Electron microscopic study in infected subjects of both groups. Conclusion: H. pylori is not the only gastric pathogen in our community, gastric giardiasis is another pathogen. Its contribution might be a factor in persistent dyspepsia after H. pylori eradication.

Keywords: dyspepsia, gastritis, Giardia lamblia, H. pylori

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Authors: Parul Johri, Mala Trivedi

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Major Intrinsic proteins (MIPs), actively involved in the passive transport of small polar molecules across the membranes of almost all living organisms. MIPs that specifically transport water molecules are named aquaporins (AQPs). The permeability of membranes is actively controlled by the regulation of the amount of different MIPs present but also in some cases by phosphorylation and dephosphorylation of the channel. Based on sequence similarity, MIPs have been classified into many categories. All of the proteins are made up of the 20 amino acids, the only difference is there in their orientations. Again all the 20 amino acids are made up of the basic five elements namely: carbon, hydrogen, oxygen, sulphur and nitrogen. These elements are responsible for giving the amino acids the properties of hydrophilicity/hydrophobicity which play an important role in protein interactions. The hydrophobic amino acids characteristically have greater number of carbon atoms as carbon is the main element which contributes to hydrophobic interactions in proteins. It is observed that the carbon level of proteins in different species is different. In the present work, we have taken a sample set of 150 aquaporins proteins from Uniprot database and a dynamic programming code was written to calculate the carbon percentage for each sequence. This carbon percentage was further used to barcode the aqauporins of animals and plants. The protein taken from Oryza sativa, Zea mays and Arabidopsis thaliana preferred to have carbon percentage of 31.8 to 35, whereas on the other hand sequences taken from Mus musculus, Saccharomyces cerevisiae, Homo sapiens, Bos Taurus, and Rattus norvegicus preferred to have carbon percentage of 31 to 33.7. This clearly demarks the carbon range in the aquaporin proteins from plant and animal origin. Hence the atom level analysis of protein sequences can provide us with better results as compared to the residue level comparison.

Keywords: aquaporins, carbon, dynamic prgramming, MIPs

Procedia PDF Downloads 342

Authors: Aysegul Evren Yapicioglu

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The social roles and responsibilities expected from citizens are increasing due to changing global living conditions. Science education is expected to prepare conscious and sensitive students. Because today’s students are the adults of future. Precondition of this task is Teacher Education. In the past decade, one of the most important research field is socioscientific issues. This study deals with advantages and disadvantages of socioscientific issue based instruction in science classroom according to pre-service science teachers’ views. A case study approach that is one of the qualitative research design was used to explore their views. Fourteen pre-service science teachers participated to instruction process. Dolphinariums, Kyoto Protocol, genetically modified organisms, recyclable black bags’ benefits and damages, genetic tests, alternative energy sources and organ donation are examples of socioscientific issues, which were taught through activities in a special teaching course. Diaries and focus group interview were used as data collection tools. As a result of the study, the advantages of socioscientific issue based instruction in science classroom comprise of six sub-categories which are multi-skilling, social awareness development of thinking, meaningful learning, character and professional development, contribution of scientific literacy whereas disadvantages of this instruction process are challenges teachers and students, limitations of teaching and learning process in pre-service science teachers’ perspectives. Finally, this study contributes to science teachers and researchers to overcome disadvantages and benefit from the advantage of socioscientific issue based instruction in science classroom.

Keywords: science education, socioscientific issues, socioscientific issue based instruction, pre-service science teacher

Procedia PDF Downloads 156

Authors: Bella Japoshvili, Zhanetta Shubitidze, Ani Bikashvili, Sophio Gabelashvili, Marina Gioshvili, Levan Mumladze

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Paravani and Saghamo Lakes are oligotrophic lentic systems located in Javakheti plateau (South Georgia) at 2073 m and 1996 m a.s.l. respectively. Javakheti plateau is known as a lakes region as there are located almost 60 small and medium size lakes. Paravani Lake is the biggest lake by its surface area in Georgia, 37 km 2. The Saghamo Lake is smaller and its surface area consists 4.58 km2. These two lakes are connected with Paravani River, because of this the main hydrobiological and ichthyological features are the same. More than 15-30 years were not studied macroinvertebrates of these lakes. Even the existing information is lack and very limited. The aim of our study was to identify main macroinvertebrate groups inhabiting both lakes and to compare obtaining results to existing information. Our investigation was carried out during 2014 and 2015, in 3 seasons of the year, in winter because of severe condition samples were not taken. Kick-net and Petersen grab were used for material collecting, 4 sites from Paravani Lake and 3–from Saghamo Lake were sampled. Collected invertebrates were fixed in ethanol and late taken to the laboratory, where organisms were identified to the lowest taxon possible, usually family. By our results identified 14 taxa for Paravani Lake and 12 taxa for Saghamo Lake. Our results differ from previous information; for Saghamo Lake previously 13 taxa and for Paravani Lake 12 taxa were described. The percentage of the groups also differ from existing information. Our investigation showed that in Paravani Lake most abundant are Apmhipoda, Hydrachnidae, and Hemiptera, in our samples the number of individuals for those 3 taxa was more than thousand, in each. For Saghamo Lake numerous taxon was Amphipoda-36.3%, following by Ephemeroptera-11.37%, Chironomidae-10.5% and Hydrachnidae-7.03% respectively. We also identified the dominant taxon for all studied seasons. Autumn is the period when the diversity of macroinvertebrates are higher in both lakes.

Keywords: Georgia, lakes, macroinvertebrates, monitoring

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Authors: Muhammad Badruzzaman, Alif Hasan, Md. Shahjahan

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Propiconazole is a triazole fungicide extensively used in agriculture which can harm to non-target organisms in aquatic environment through runoff. Chronic exposure to environmental pesticides turn to behavioral impairment in vertebrates including teleosts. However, the potential effect of this fungicide on neurobehavioral impairment and release from it in vertebrates has not been fully explored. In this work, we examined the role of melatonin to rescue fungicide induced neurobehavioral and reproductive alternation and its connection with changes in dopaminergic activity in the brain of Mystus cavasius. After fish were exposed to water containing propiconazole at 0, 0.1, 5, and 250 µg/L for 3 days, significant increases of DA, 3,4-dihydroxyphenylacetic acid (DOPAC; a DA metabolite), and their ratio (DOPAC/DA) were observed in whole brain at 250 µg/L concentration. When fish were treated with propiconazole at 250 µg/L for 3 days, there was a significant elevation of DA, DOPAC and DOPAC/DA in diencephalon and pituitary, and only DA in the telencephalon, compared with control fish. Besides, it induced a reduction in extracellular serotonin and had an anxiolytic-like effect, supported by a decrease in cortisol production. Increased locomotor activity, anxiety and aggressiveness, decreased gonadosomatic index with few vitellogenic oocytes in ovaries after propiconazole treatment. When fish were treated with melatonin, D1 (SCH-23390) or D2 (Haloperidol) dopamine receptor antagonists and combined of melatonin and D1/D2 receptor antagonist and was observed melatonin + D2 receptor antagonist rescued fungicide induced all behavioral changes in fish. These results indicate that propiconazole increases locomotor activity, anxiety and aggressiveness and decreases reproductive activity, which was rescued by combined treatment of melatonin and dopamine receptor antagonist.

Keywords: behavior, catfish, dopamine, fungicide, melatonin

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Authors: Devadrita Dey Sarkar

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Oxidosqualene cyclase is a membrane bound enzyme in which helps in the formation of steroid scaffold in higher organisms. In a highly selective cyclization reaction oxidosqualene cyclase forms LANOSTEROL with seven chiral centres starting from the linear substrate 2,3-oxidosqualene. In humans OSC in cholesterol biosynthesis it represents a target for the discovery of novel anticholesteraemic drugs that could complement the widely used statins. The enzyme oxidosqualene: lanosterol cyclase (OSC) represents a novel target for the treatment of hypercholesterolemia. OSC catalyzes the cyclization of the linear 2,3-monoepoxysqualene to lanosterol, the initial four-ringed sterol intermediate in the cholesterol biosynthetic pathway. OSC also catalyzes the formation of 24(S), 25-epoxycholesterol, a ligand activator of the liver X receptor. Inhibition of OSC reduces cholesterol biosynthesis and selectively enhances 24(S),25-epoxycholesterol synthesis. Through this dual mechanism, OSC inhibition decreases plasma levels of low-density lipoprotein (LDL)-cholesterol and prevents cholesterol deposition within macrophages. The recent crystallization of OSC identifies the mechanism of action for this complex enzyme, setting the stage for the design of OSC inhibitors with improved pharmacological properties for cholesterol lowering and treatment of atherosclerosis. While studying and designing the inhibitor of oxidosqulene cyclase, I worked on the pdb id of 1w6k which was the most worked on pdb id and I used several methods, techniques and softwares to identify and validate the top most molecules which could be acting as an inhibitor for oxidosqualene cyclase. Thus, by partial blockage of this enzyme, both an inhibition of lanosterol and subsequently cholesterol formation as well as a concomitant effect on HMG-CoA reductase can be achieved. Both effects complement each other and lead to an effective control of cholesterol biosynthesis. It is therefore concluded that 2,3-oxidosqualene cyclase plays a crucial role in the regulation of intracellular cholesterol homeostasis. 2,3-Oxidosqualene cyclase inhibitors offer an attractive approach for novel lipid-lowering agents.

Keywords: anticholesteraemic, crystallization, statins, homeostasis

Procedia PDF Downloads 324

Authors: Qiongpeng Dan, Xiyao Li, Qiong Zhang, Yongzhen Peng

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The nutrients removal from wastewater is of great significance for global wastewater recycling and sustainable reuse. Traditional nitrogen and phosphorus removal processes are very dependent on the input of aeration and carbon sources, which makes it difficult to meet the low-carbon goal of energy saving and emission reduction. This study reported a proof-of-concept demonstration of integrating anammox and enhanced biological phosphorus removal (EBPR) by flocs management in a single-stage hybrid bioreactor (biofilms and flocs) for simultaneous nitrogen and phosphorus removal (SNPR). Excellent removal efficiencies of nitrogen (97.7±1.3%) and phosphorus (97.4±0.7%) were obtained in low C/N ratio (3.0±0.5) municipal wastewater treatment. Interestingly, with the loss of flocs, anammox bacteria (Ca. Brocadia) was highly enriched in biofilms, with relative and absolute abundances reaching up to 12.5% and 8.3×1010 copies/g dry sludge, respectively. The anammox contribution to nitrogen removal also rose from 32.6±9.8% to 53.4±4.2%. Endogenous denitrification by flocs was proven to be the main contributor to both nitrite and nitrate reduction, and flocs loss significantly promoted nitrite flow towards anammox, facilitating AnAOB enrichment. Moreover, controlling the floc's solid retention time at around 8 days could maintain a low poly-phosphorus level of 0.02±0.001 mg P/mg VSS in the flocs, effectively addressing the additional phosphorus removal burden imposed by the enrichment of phosphorus-accumulating organisms in biofilms. This study provides an update on developing a simple and feasible strategy for integrating anammox and EBPR for SNPR in mainstream municipal wastewater.

Keywords: anammox process, enhanced biological phosphorus removal, municipal wastewater, sustainable nutrients removal

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Authors: Eric Gismondi, Aurelie Bigot-Clivot

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Endocrine disruptors (EDCs) are well known to disrupt the development and the reproduction of exposed organisms. Although this point has been studied in vertebrate models, the limited knowledge of the endocrine system of invertebrates makes the evaluation of EDCs effects difficult. However, invertebrates represent the major part of aquatic ecosystems, such as amphipods Gammaridea, which are crucial for their functioning (e.g., litter degradation, food resource). Moreover, gammarids are hosts of parasites such as vertically-transmitted microsporidia (microsporidia VT), which could be confounding factors in assessment of EDC effects. Indeed, some microsporidia VT could have endocrine effects by their own present in the host since it was observed for example, a feminization of juvenile males, which become phenotypic females. This work evaluated the impact of ethinylestradiol (EE₂, estrogenic), cyproterone acetate (CPA, anti-androgenic), 4-hydroxytamoxifen (4HT, anti-estrogenic) and 17α-methyltestosterone (17MT - androgenic), on the 20-hydroxyecdysone concentration (i.e. 20HE - molt process) and the vitellogenin gene expression (i.e. reproduction) in the freshwater amphipod Gammarus pulex, after a 96h laboratory exposure. In addition, the presence of microsporidia VT was verified in order to analyze the effect of this confounding factor. Results of this study shown that, although endocrine systems of invertebrates and vertebrates are different, EDCs proved in vertebrates could also affect biological functions hormonally controlled in invertebrates. Indeed, the molt process of crustaceans was disrupted in the first stage (i.e. 20-HE concentration) and therefore, could affect, at the long term, the population dynamic. In addition, it was observed that G. pulex was differently impacted according to the gender and parasitism, which underline the importance to take into account these confounding factors to better evaluate the EDCs impact on invertebrate populations.

Keywords: endocrine disruption, gammarus sp., molt, parasitism

Procedia PDF Downloads 145