Application of a Multi-Criteria Decision-Making Approach for Ranking Environmental Risks Caused by Petrochemical Industries: A Case Study of a Sodium Carbonate Production Unit

The occurrence of accidents in petrochemical industries that cause environmental catastrophes has persuaded experts to use risk-oriented approaches. The approach is to rank the key elements of risk assessment by which the priority of each risk is specified compared to the other ones. The present study was performed to test the applicability of a multi-criteria decision-making approach for prioritizing environmental risks of a petrochemical complex in southwestern Iran. Accordingly, all risky activities of the Sodium Carbonate Production Unit (SCPU) were identified initially. Afterward, the relevant environmental components affected by the risky activities were specified. According to the specification, the most significant risks were shortlisted using experts’ judgment based on three criteria: “impact intensity,” “occurrence probability,” and the “extent of contamination dispersion in the environment.” The shortlisted environmental risks were then prioritized by the Method “Elimination et Choice Translating Reality (Elimination and Choice Expressing Reality)” abbreviated as ELECTRE. Based on the obtained results, “decreased air quality” and “manpower health threatening” are the top-priority risks while “poor quality of groundwater” was identified as the least priority risk. In a general conclusion, a multi-criteria decision-making approach is quite useful for assessing environmental risks of petrochemical industries.     

Sarcoplasmic reticulum Ca-ATPase-phospholamban interactions and dilated cardiomyopathy

Dilated cardiomyopathy is a disease of the heart muscle resulting from a diverse array of conditions that damages the heart and impairs myocardial function. Heart failure occurs when the heart is unable to pump blood at a rate which can accommodate the heart muscle's metabolic requirements. Several signaling pathways have been shown to be involved in the induction of cardiac disease and heart failure. Many of these pathways are linked to cardiac sarcoplasmic reticulum (SR) Ca cycling directly or indirectly. A large body of evidence points to the central role of abnormal Ca handling by SR proteins, Ca-ATPase pump (SERCA2a) and phospholamban (PLN), in pathophysiological heart conditions, compromising the contractile state of the cardiomyocytes. This review summarizes studies which highlight the key role of these two SR proteins in the regulation of cardiac function, the significance of SERCA2a-PLN interactions using transgenic approaches, and the recent discoveries of human PLN mutations leading to disease states. Finally, we will discuss extrapolation of experimental paradigms generated in animal models to the human condition.     

Investigation of Microstructure and Corrosion of TiNbTaZrMo High-Entropy Alloy in the Simulated Body Fluid

Microstructures and corrosion of TiNbTaZrMo(Ti₂₀Nb₂₀Ta₂₀Zr₂₀Mo₂₀)High-Entropy Alloy(HEA)were investigated in the Simu-lated Body Fluid(SBF).Microstructure of this alloy was investigated by X-Ray Difiraction(XRD)and Scanning Electron Microscopy(SEM)techniques.Our observations confirmed the presence of two bcc phases as the major matrix as well as another minor phase in themicrostructure of the alloy.Concentration of some elements,such as tantalum,niobium,and molybdenum in the dendritic branches and thepresence of zirconium and titanium in the inter-dendritic branches were clearly evidenced by Energy Dispersive X-ray(EDX)analysis.Given importance of corrosion of implant alloys in the human's body,elctrochemical impedance and cyclic polarization tests werepcerformed on the alloy in SBF.Through the corrosion tests,corrosion potential,current,and resistance were obtained as E_corr=-0.42 V,i_corr=0.34μA·cm^-2,and R_p=27.44 k ohm·cm²,respectively.The results revealed that the rate of corrosion in TiNbTaZrMo HEA is about 26 times better than that of Ti₆Al₄V alloy.Also,both alloys had no pitting corrosion in the SBF solution.     

Rate of recalls in congenital hypothyroidism based upon a regional survey in Isfahan, Iran, using serum T4 and TSH analyses: comparison of two different recall methods

AIMS: To evaluate and compare the recall rate in congenital hypothyroidism screening project in Isfahan, first using an approach involving measures of both TSH and T4 and then using TSH alone. METHODS: From June 2002 to January 2005, serum TSH and T4 level of referred neonates were measured at 3rd to 7th day of birth through venous sampling. If neonates' serum TSH was >20 mIU/l or T4 was <6.5 microg/dl by the first protocol, or TSH was >20 mIU/l by the second protocol, they were recalled. TSH and T4 were measured using an immunoradiometric assay and radioimmunoassay, respectively. Neonates with TSH > 10 and T4 < 6.5 on their second measurement were considered as congenitally hypothyroid. RESULTS: Serum T4 and TSH of 29,425 neonates by first and 57,235 neonates by second recall approach were measured. Recall rate was higher in the first protocol (2.2% vs. 0.6%, p < 0.05). Most of the recalled neonates in the first protocol were recalled for low T4 level (p < 0.05). The prevalence of CH was 1 in 350 livebirths. CONCLUSION: Although the recall rate was in the acceptable range by either approach, the TSH alone protocol seems to be a more sensitive and practical approach with the least recall burden and considering the high prevalence of CH in our region merit adaptation of widespread screening for CH using TSH measurements from heel stab blood spotted on filter paper.     

Imidazolium or guanidinium/layered manganese (III, IV) oxide hybrid as a promising structural model for the water-oxidizing complex of Photosystem II for artificial photosynthetic systems

Photosystem II is responsible for the light-driven biological water-splitting system in oxygenic photosynthesis and contains a cluster of one calcium and four manganese ions at its water-oxidizing complex. This cluster may serve as a model for the design of artificial or biomimetic systems capable of splitting water into oxygen and hydrogen. In this study, we consider the ability of manganese oxide monosheets to self-assemble with organic compounds. Layered structures of manganese oxide, including guanidinium and imidazolium groups, were synthesized and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction spectrometry, and atomic absorption spectroscopy. The compounds can be considered as new structural models for the water-oxidizing complex of Photosystem II. The overvoltage of water oxidation for the compounds in these conditions at pH = 6.3 is ~0.6 V. These compounds may represent the first step to synthesize a hybrid of guanidinium or imidazole together with manganese as a biomimetic system for the water-oxidizing complex of Photosystem II.     

In silico experiment with an-antigen-toll like receptor-5 agonist fusion construct for immunogenic application to Helicobacter pylori

BACKGROUNDS:

Helicobacter pylori colonize the gastric mucosa of half of the world''s population. Although it is classified as a definitive type I carcinogen by World Health Organization, there is no effective vaccine against this bacterium. H. pylori evade the host immune response by avoiding toll-like detection, such as detection via toll-like receptor-5 (TLR-5). Thus, a chimeric construct consisting of selected epitopes from virulence factors that is incorporated into a TLR-5 ligand (Pseudomonas flagellin) could result in more potent innate and adaptive immune responses.

MATERIALS AND METHODS:

Based on the histocompatibility antigens of BALB/c mice, in silico techniques were used to select several fragments from H. pylori virulence factors with a high density of B- and T-cell epitopes.

RESULTS:

These segments consist of cytotoxin-associated geneA (residue 162-283), neutrophil activating protein (residue 30-135) and outer inflammatory protein A (residue 155-268). The secondary and tertiary structure of the chimeric constructs and other bioinformatics analyses such as stability, solubility, and antigenicity were performed. The chimeric construct containing antigenic segments of H. pylori proteins was fused with the D3 domain of Pseudomonas flagellin. This recombinant chimeric gene was optimized for expression in Escherichia coli. The in silico results showed that the conserved C- and N-terminal domains of flagellin and the antigenicity of selected fragments were retained.

DISCUSSION:

In silico analysis showed that Pseudomonas flagellin is a suitable platform for incorporation of an antigenic construct from H. pylori. This strategy may be an effective tool for the control of H. pylori and other persistent infections.     

Inhibition of the Jun kinase pathway blocks DNA repair, enhances p53-mediated apoptosis and promotes gene amplification.

We have previously shown, by expression of a nonphosphorylatable dominant inhibitor mutant of c-Jun [cJun(S63A,S73A)], that activation of the NH2-terminal Jun kinase/stress-activated protein kinase by genotoxic damage is required for DNA repair. Here, we examine the consequences of inhibition of DNA repair on p53-induced apoptosis in T98G cells, which are devoid of endogenous wild-type p53. Relative to parental or wild-type c-Jun-expressing control cells, mutant Jun-expressing T98G clones show similar growth rates and plating efficiencies. However, these cells are unable to repair DNA (PCR-stop assays) and exhibit up to an 80-fold increased methotrexate-induced colony formation due to amplification of the dihydrofolate reductase gene. Moreover, the mutant c-Jun clones exhibit increased apoptosis and elevated bax:bcl2 ratios on expression of wild-type p53. These results indicate that inhibition of DNA repair leads to accumulation of DNA damage in tumor cells with unstable genomes and this, in turn, enhances p53mediated apoptosis.     

A Neuron-Glial Trans-Signaling Cascade Mediates LRRK2-Induced Neurodegeneration

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Ethanol-induced impairment of polyamine homeostasis – A potential cause of neural tube defect and intrauterine growth restriction in fetal alcohol syndrome

Introduction

Polyamines play a fundamental role during embryogenesis by regulating cell growth and proliferation and by interacting with RNA, DNA and protein. The polyamine pools are regulated by metabolism and uptake from exogenous sources. The use of certain inhibitors of polyamine synthesis causes similar defects to those seen in alcohol exposure e.g. retarded embryo growth and endothelial cell sprouting.

Methods

CD-1 mice received two intraperitoneal injections of 3 g/kg ethanol at 4 h intervals 8.75 days post coitum (dpc). The fetal head, trunk, yolk sac and placenta were collected at 9.5 and 12.5 dpc and polyamine concentrations were determined.

Results

No measurable quantity of polyamines could be detected in the embryo head at 9.5 dpc, 12 h after ethanol exposure. Putrescine was not detectable in the trunk of the embryo at that time, whereas polyamines in yolk sac and placenta were at control level. Polyamine deficiency was associated with slow cell growth, reduction in endothelial cell sprouting, an altered pattern of blood vessel network formation and consequently retarded migration of neural crest cells and growth restriction.

Discussion

Our results indicate that the polyamine pools in embryonic and extraembryonic tissues are developmentally regulated. Alcohol administration, at the critical stage, perturbs polyamine levels with various patterns, depending on the tissue and its developmental stage. The total absence of polyamines in the embryo head at 9.5 dpc may explain why this stage is so vulnerable to the development of neural tube defect, and growth restriction, the findings previously observed in fetal alcohol syndrome.