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Genome-Editing Strategy for Medicinal Plants Growing under Adverse Environmental Pollution
Published in Azamal Husen, Environmental Pollution and Medicinal Plants, 2022
The breakdown of contaminants by plants is termed phytodegradation or phytotransformation. Plants take up the contaminants and break them down with the help of enzymes through the metabolic process (Table 13.5). Enzymes catalyse and accelerate the degradation of organic pollutants and convert them into simpler forms which further aid in plant growth. Trinitrotoluene (TNT), an explosive, has contaminated many sites due to the limited success of remediation techniques. However, many plant species were found able to break down TNT. The phytodegradation of TNT has major limitations as it affects the growth of the plants. One of the soil bacteria (Entereo cloaca) was found to utilize this explosive as its nitrogen source. Two enzymes (PETN reductase and nitroreductase) were responsible for degrading the TNT into a harmless product. The gene responsible for producing these two enzymes were transferred into tobacco plants. This led to the formation of a transgenic tobacco plant to degrade TNT more efficiently without compromising its growth.
Acute Lung Injury In Children Due To Chemical And Physical Agents
Published in Lourdes R. Laraya-Cuasay, Walter T. Hughes, Interstitial Lung Diseases in Children, 2019
In a study of the famlilies of 987 second grade school children living near a TNT (trinitrotoluene) plant in Chattanooga, Tenn., a relative excess in acute respiratory illness of 18.8% was found in families residing in an area of high nitrogen dioxide concentration and an excess of 10.4% in an area of high suspended particulate exposure in comparison to two control areas.344 In the same area, a retrospective study of lower respiratory tract illness among 3217 infants and children showed that among children in a high nitrogen dioxide area, both the relative proportion of children affected and the frequency of illness were higher than those in lower pollution areas.345 Follow-up study of this area 4 years later, when air quality had been improved and when the TNT plant was temporarily closed by a strike, showed continued excess illness rates in the previously polluted areas, but at a lower rate, which was further reduced as the strike continued.346
Techniques for Performing Stoichiometric Calculations
Published in Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk, Survival Guide to General Chemistry, 2019
Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk
The following reaction shows the synthesis of the explosive trinitrotoluene (TNT): How many grams of HNO3 are required to exactly react with 454 grams of C7H8?How many grams of TNT (theoretical yield) can be formed from 829 grams of C7H8?How many grams of C7H8 are required to form 2.00 kilograms of TNT?
In vitro metabolism of HMTD and blood stability and toxicity of peroxide explosives (TATP and HMTD) in canines and humans
Published in Xenobiotica, 2021
Michelle D. Gonsalves, Lindsay McLennan, Angela L. Slitt, James L. Smith, Jimmie C. Oxley
Energetic materials can be classified by chemical structure; including nitrate esters, nitroaromatics, nitroamines, peroxide, and others. The toxicity of most military explosives is well-characterised, with even some therapeutic properties being identified. For example, nitrate ester explosives, such as nitroglycerine and pentaerythritol tetranitrate (PETN), are widely used as vasodilators to treat angina (FDA 2014). Ill side effects have been linked to other explosives. Nitroaromatic explosives, such as TNT (2,4,6-trinitrotoluene), picric acid (2,4,6-trinitrophenol), and tetryl (2,4,6-trinitrophenyl-N-methylnitramine), may cause cytotoxicity, their metabolic pathways include single- or two-electron enzymatic reduction that forms radical species (Nemeikaite-Ceniene et al.2006). Nitroamine explosives, such as RDX (1,3,5-trinitro-1,3,5-triazinane) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazoctane), may be carcinogenic, their metabolic pathways promote the formation of N-nitroso species which cause genetic damage (Pan et al.2007). However, the metabolic pathways and toxicity of peroxide explosives, such as triacetone triperoxide (TATP) (Colizza et al.2019, Gonsalves et al.2020) and hexamethylene triperoxide diamine (HMTD, Figure 1) have not been thoroughly investigated.
Exposure to impulse noise at an explosives company: a case study
Published in International Journal of Occupational Safety and Ergonomics, 2018
Aleksandra Kulik, Jolanta Malinowska-Borowska
One of a few Polish and international studies analyzing the levels of noise generated during detonation of explosives was conducted by Młyński et al. [19]. These authors determined a number of parameters characterizing impulse noise generated during detonations and explosions. The analyzed explosives included trinitrotoluene (TNT), ammonium nitrate/fuel oil (ANFO) and hexogen (RDX). Mean values of LCpeak ranged between 130 and 137 dB, and thus were lower than those documented in our study in the blasting testing area. Also, LAmax values were lower, ranging between 100 and 105 dB. These discrepancies likely result from variable chemical composition and weight of the used explosives. Młyński et al. [19] determined the levels of sound at an outdoor measurement point 150 m from the TNT detonation site and in the blast bunker 15 m from the RDX and ANFO detonation sites. Moreover, the load of the latter two explosives (400 g) was markedly lower than the 1-kg dynamite load used in our study.
Functionality of receptor targeted zinc-insulin quantum clusters in skin tissue augmentation and bioimaging
Published in Journal of Drug Targeting, 2021
Pawandeep Kaur, Diptiman Choudhury
Further, the use of nano-clusters and a variety of quantum dots for bioimaging and wound recovery activities have been reported by many groups, for example, Das NK et al. [24] prepared glutathione-Cu nanoclusters having non-toxic behaviour and bind particularly with the nuclear membrane and emit blue fluorescence and tested its bio-imaging properties against human cell lines. Researchers have also developed quantum dots on the insulin platform and used those for various biological activities like bio-imaging and wound healing. Liu CL et al. have synthesised biocompatible and bioactive fluorescent Insulin-Au quantum clusters and then used that formulation for bio-imaging on brain cells and C2C12 myoblast cell lines. They also showed its utility to maintain the blood glucose level in vivo [25]. Kaur P et al. [16] showed the use of crystalline copper insulin quantum clusters (ICuQCs) for insulin receptor-targeted bio-imaging of A549 and HeLa cells in vitro. Amorphous fluorescent particles have recently caught the eye of researchers for their excellent, biocompatibility, solubility, and stability, for example, amorphous luminescent bovine serum protected gold clusters hosted on nanofibres prepared by Subramanian V et al. [26] and explored for the detection of trinitrotoluene in trace amount. Amorphous carbon dots self-passivated in bulk quantity synthesised by Siddique AB et al. [27] and used to detect 2,4,6-trinitrophenol (TNP), an explosive in trace amounts. Polymorphic crystalline copper iodide clusters with bright green emission were prepared by Benito Q et al. [28] and studied their mechano-chromic luminescence properties in which Cu4I4 shows Cu–Cu intermolecular distance shortening through the disruption in crystal packing. Yang H et al. [29] synthesised heterojunctions of iron oxyhydroxide/g-C3N4 amorphous nanosheets for enhanced photocatalytic activity. Wang G et al. [30] synthesised metastable crystalline dual phased ZnSb-based films and explored its Insulator-metal transition (IMT) properties. Amorphous (ZnS) nanoparticles conjugated with BSA synthesised by Cao Y et al. [31] to check its inhibition effect on the growth of tumour cells. Xie J et al. [32] used Amorphous and crystalline protein metal clusters for the bioimaging purpose of the brain cells. In the case of an amorphous arrangement, metal protein clusters constitute atoms that do not have the ordered or regular pattern means the arrangement of the constituents i.e. atoms in such cases has only short-range or over a short distance [33].