Endocrine-Disrupting Properties Of Pharmaceuticals And Personal Care Products (ppcps): An Evaluation Using Aquatic Model Organisms

Thousands of chemicals have introduced into the environment as a result of human activity since the industrial revolution, and the U.S. Government Accountability Office has estimated that as many as 1,500 new chemical entities are synthesized each year ( Key Issues: Toxic Chemicals - High Risk Issue, 2017). Many of these chemicals are now found in surface water and ground water and can have detrimental effects on environmental health and on human health. This anthropogenic contamination has resulted in the labeling of the diverse array of chemicals found in water, which are not routinely monitored or regulated, as contaminants of emerging concern or CECs. Some of the CECs of greatest concern are those capable of disrupting endocrine system function. The endocrine system of humans and wildlife is designed to be very sensitive to endogenous signaling molecules we call hormones. Exogenous chemicals that can mimic or augment the signaling by hormones are capable of disrupting the normal function of endocrine systems, and this subset of CECs has been called endocrine disrupting chemicals or EDCs. EDCs can have a broad range of deleterious impacts on biological function and can affect development and reproduction, and cause cancer. Although EDC effects have been reported in the literature, the number of newly released and existing chemicals in the environment underscores the need for better EDC detection tools. Some of the most commonly observed evidence for endocrine disruption in the environment comes from the observation of feminized male fish or altered sex ratios with fewer males downstream of wastewater effluent outfalls. Evidence strongly suggests that these EDC effects are due to the estrogenic and/or anti-androgenic influence of chemical contaminants in the water. Some of the known or suspected EDCs fall into the category of pharmaceuticals and personal care products (PPCPs). We proposed that two aquatic model organisms, one invertebrate – Daphnia pulex (waterflea), and one vertebrate - Danio rerio (zebrafish), can be used to detect the estrogenicity and anti-androgenic effects of known or suspected PPCPs in water. The hypothesis was that known or suspected EDCs have detectable behavioral effects, and that the characterization of these behavioral effects, when combined with developmental and gene expression data, will enable the creation of a mathematical model that can identify chemicals contributing to the estrogenicity or ant-angdrogenic qualities of contaminated water. Furthermore, the study of the impact of EDCs on the behavior of two different aquatic organisms can increase the discriminating power of the behavioral results and broaden the application of these results to the assessment of potential ecological impact. This study of behavioral effects is one component of a larger EDC project, and it focused on selected PPCPs suspected or known to be endocrine disrupting chemicals: estrone, triclosan (TCS), triclocarban (TCC), and metformin. A novel optical bioassay examined the effects of these four chemicals on the swimming behavior of the two different aquatic species. Significant concentration-dependent differences in responses were found across the series of chemicals and between species for a given chemical (metformin, estrone), and similar responses to one chemical were found for both species (TCS). These behavioral studies in conjunction with the planned morphological evaluation of development will provide the foundation for interpreting the effects of EDCs on gene expression in the last phase of the project, and the creation of the initial prototype of a mathematical model to predict the nature of the chemical entities contributing to the estrogenic or anti-androgenic qualities of water samples. This new bioassay approach will compliment and expand the power of existing analytical chemistry techniques and enable more efficient evaluation of the complex issues associated with the contamination of aquatic systems by CECs

Effects Of Molar Ratio Of Iron Catalyst On Synthesis Of Carbon Nanotubes Via Catalytic Chemical Vapor Deposition

Research on the area of the synthesis of carbon nanotubes is fundamental and critical to the entire subject of carbon nanotubes. This dissertation describes an experiment to synthesize carbon nanotubes by the method of catalytic chemical vapor deposition (CCVD). It focuses on the relationship between the as-prepared catalyst and the synthesized carbon nanotubes. The effect of growth parameters for the synthesis of carbon nanotubes was also studied. The Fe-Mo-MgO catalysts with five different molar ratios of iron (Fe) in this composite catalyst were prepared through the impregnation method. The goal of this work was to identify the suitable molar ratio of iron (Fe) in the composite catalyst of Fe-Mo-MgO on which carbon nanotubes (CNTs) can be grown with a higher yield and quality.Scanning electron microscopy (SEM), transmission electron microscopy (TEM), xray diffraction (XRD), and thermogravimetric analysis (TGA) were used to characterize the as-prepared catalysts and as-grown carbon nanotube samples. Among these catalysts with different molar ratio of iron, the main and obvious observation in the synthesis of carbon nanotubes was the yield of synthesized carbon nanotubes. That is, increasing the molar ratio of iron, the yield of produced carbon nanotubes increases strongly, but the quality did not improve. While by decreasing the Fe concentration, both the structural defects and yield were reduced. Therefore, based on the experimental results, the best catalyst was catalyst 3 (Fe: Mo: MgO = 0.5: 0.1: 10) with a moderate molar ratio of iron. This catalyst not only had good yield but also good quality. The different parameters such as flow rate of argon (Ar) as a carrier gas, and temperature to improve the growth condition of CCVD method for the synthesis of CNTs by Fe-Mo-MgO catalyst were examined. It is found that the best flow rate for carrier gas is 100 ml/min. For the flow rate lower or higher than this, there were very few CNTs formed, since the low flow rate of Ar could not carry enough ethanol vapors through the reactor to be deposited on the catalyst. As for the high flow rate of Ar, most of the carbon source exited from the outlet of the reactor and again they could not be deposited on the catalyst, thus few carbon nanotubes were formed. In the synthesis of carbon nanotubes by CCVD method, the temperature plays a key role. The results show that when the temperature is lower than 750°C, few CNTs were formed, and when the temperature is higher than 900°C, more and more amorphous carbons were formed in the CNTs. The best temperature for the growth of carbon nanotubes by these catalysts is between 800°C and 900°C. The results showed that the growth of carbon nanotubes was significantly influenced by the reaction condition due to its sensitivity. The synthesis products were always a mixture of single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs)

Load-Deflection Behaviour of Frp Concrete Composite Deck

Nowadays, Fiber Reinforced Polymer (FRP) concrete composite bridge deck system hasbeen introduced because of its light-weight and durability. Strong composition is neededbetween FRP and concrete to acquire the structural composite behavior of FRP concretecomposite deck. FRP has unique properties that, if disregarded, can lead to failure duringoperation. However, when these same unique properties are taken into advantages, they canprovide the engineers with a system superior to traditional metallic materials. This studyinvestigates analytically the deflection behavior of FRP concrete composite deck using shearconnectors under flexural loading. Finite element software (LUSAS) is used to model FRPcomposite deck. For this purpose, LUSAS has introduced some elements. Volume elementsare utilized to model concrete and Glass Fiber Reinforced Polymer (GFRP) section. Meshingelements are necessary in finite element in order to act as a member in modeling. 3D solidcontinuum elements are used to mesh the sample. Five GFRP module having differentthicknesses of 8mm, 9.6mm, 11.2mm, 12.8mm and 16mm are taken to analyze. Results showthat the thicknesses of GFRP module have significant effect on the ultimate load anddeflection of the deck. Once the thickness of GFRP section increased, the deflection at midspan decreased and the ultimate load increased accordingly. Furthermore, results revealed theappropriate interface material between FRP and concrete in finite element modeling. In orderto get an effective interface element, about 40 numerical models have been analyzed. Theresults were compared with experimental study. Inserted data for verified model in LUSASwere demonstrated as an appropriate interface element between FRP and concrete

2S albumin g13 polypeptide, less related to Fag e 2, can be eliminated in common buckwheat (Fagopyrum esculentum Moench) seeds

2S albumin (g11, g13, g14, and g28) is an important allergen in common buckwheat (Fagopyrum esculentum). g13 is hydrophobic, rare in seeds, and may show distinct allergenicity from the others; therefore, we tried to eliminate this protein. Phylogenetic and property distance analyses indicated g13 is less related to g14 (Fag e 2) than g11/g28 is related to g14, particularly in the second domain containing the II and III α-helices. A null allele with a 531 bp insertion in the coding region was found for g13 at an allele frequency of 2 % in natural populations of common buckwheat. The g13_null allele homozygote accumulated no g13 protein. A BLAST search for the 531 bp insertion suggested the insert-like sequence resided frequently in the buckwheat genome, including the self-incompatibility responsible gene ELF3 in Fagopyrum tataricum. The g13_null insert-like sequence could, therefore, help in producing hypoallergenic cultivars, and expand the genetic diversity of buckwheat

Characterization of 2S albumin allergenic proteins for anaphylaxis in common buckwheat

2S albumin (2SA) is responsible for anaphylaxis following consumption of buckwheat in allergic individuals. To reduce allergen incidents, characterization of 2SA polypeptides is prerequisite, thus was analyzed in this study. Of the five 2S albumin genes (g03, g11, g13, g14, and g28), g03 was seemingly non-functional. The g14 content was 3- and 40-fold higher than that of g11/g28 and g13, respectively. The g11/g28 were more processed to a ∼8 kDa band from a 16 kDa band than g14 in seeds, agreeing with that g11/g28 have high similarity with Fag e 8kD. Meanwhile, anti-g13 produced only a single ∼10 kDa band. Modification of g13 and domain exchange between g13 and g14 suggested that the hydrophobicity of the first domain and the nature of some amino acids in g13 contributed, at least in part, to the lower apparent molecular weight of g13 than expected. Thus, g13 might be an unexplored and noteworthy allergen

Characterisation of the cellular basis of beta-lactam induced skin and liver injury

Drug hypersensitivity reactions are a significant cause of patient morbidity and mortality. They are difficult to predict in the clinic and during the drug development process. This is because mechanisms have not been fully elucidated. In fact, recent data using T-cells cloned from hypersensitive human patients have questioned the long-standing hapten concept, which states that a drug must bind irreversibly to protein to initiate a T-cell response. The work described herein was performed to investigate the chemical and cellular mechanisms of β-lactam-induced skin and liver injury and in particular to understand the relationship between drug-protein adduct formation and the activation of antigen-specific T-cells. Β-lactam antibiotics, such as piperacillin, provide the cornerstone of treatment and reduce the rate of decline in lung function in patients with cystic fibrosis, but use is limited by a high frequency of hypersensitivity reactions. Using the lymphocyte transformation test, drug-responsive lymphocytes were found in approximately 70% of clinically diagnosed piperacillin hypersensitive patients. By cloning over 400 antigen-specific CD4+, CD8+ and CD4+CD8+ T-cells, the T-cell proliferative response and cytokine secretion to piperacillin was shown to be concentration-dependent and highly drug-specific. Mass spectrometry revealed irreversible binding of piperacillin to selective lysine residues on albumin and a synthetic albumin conjugate stimulated piperacilin-specific clones via a processing-dependent pathway. These results describe the cellular processes that underlie piperacillin hypersensitivity. Approximately 20% of hypersensitive patients with cystic fibrosis develop multiple reactions that restrict therapeutic options. To explore the mechanistic basis of multiple β-lactam hypersensitivity, albumin binding profiles and T-cell responses against three commonly prescribed drugs; piperacillin, meropenem and aztreonam, were studied. PBMC responses were characterized using the lymphocyte transformation test and IFN-γ ELIspot. Clones were generated and found to proliferate and release cytokines following stimulation with all three drugs. However, crossreactivity with the different drugs was not observed. Each compound formed distinct haptens with lysine residues on albumin, which may explain the highly drug-specific T-cell response. These data indicate that multiple β-lactam reactions are instigated through priming naïve T-cells against the different drugs. The role of the adaptive immune system in reactions that target liver has not been defined. For flucloxacillin, a delay in the reaction onset and identification of HLA-B*57:01 as a susceptibility factor are indicative of an immune pathogenesis. Thus, flucloxacillin-responsive CD4+ and CD8+ T-cells were characterized from patients with liver injury. Clones expressed the gut-homing chemokine receptors CCR4 and CCR9 and secreted IFN-γ, Th2 cytokines and cytolytic molecules following drug stimulation. In contrast to the piperacillin clones, flucloxacillin clones were activated with several structurally-related β-lactam antibiotics. Furthermore, naïve CD8+ T-cells from volunteers expressing B*57:01 were activated with flucloxacillin when dendritic cells presented the drug antigen. Activation of CD8+ cells from patients and volunteers was processing-dependent and restricted by HLA-B*57:01, which effectively links the genetic association to the iatrogenic disease. In conclusion, the studies described herein provide novel insight into the way in which β-lactam antibiotics interact with protein and activate T-cells that are thought to be the ultimate mediators of drug hypersensitivity reactions in skin and liver