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Arsenals of Pharmacotherapeutically Active Proteins and Peptides: Old Wine in a New Bottle
Published in Debarshi Kar Mahapatra, Swati Gokul Talele, Tatiana G. Volova, A. K. Haghi, Biologically Active Natural Products, 2020
Hemoglobin is not only involved in transport of oxygen but also helps in transport of gases like carbon dioxide (CO2), carbon monoxide (CO), and nitric oxide (NO) [70]. Carbon monoxide binds more strongly to hemoglobin and forms carboxyhemoglobin which does not dissociate readily and is the source of carbon monoxide poisoning [71]. Nitric oxide combines with deoxygenated hemoglobin to form methemoglobin wherein the iron ion has +3 charge, Fe3+, and releases nitrate ions. Hemoglobin is regenerated back from methemoglobin by various mechanisms. Nearly 1% of hemoglobin is converted to methemoglobin on daily basis. Serious conditions like methemoglobinemia results on ingestion nitorbenzenes and nitrites, enzyme deficiencies of as methemoglobin reductase or diaphorases, and abnormal hemoglobins (HbM). In such conditions, nearly 1/4th of hemoglobin becomes non-functional [70, 71]. Mild methemoglobinemia does not require treatment. Ascorbic acid and methylene can be used to treat the conditions [73].
Toxic Responses of the Blood
Published in Stephen K. Hall, Joana Chakraborty, Randall J. Ruch, Chemical Exposure and Toxic Responses, 2020
The iron in the heme of hemoglobin is normally in the ferrous state (Fe2+), but it can be oxidized by certain chemicals to the ferric state (Fe3+). The resulting pigment is known as methemoglobin. Methemoglobinemia can be hereditary, owing to a rare genetic defect in the hemoglobin molecule, or lack of the red blood cell enzyme that converts methemoglobin back to hemoglobin after the red blood cells take up oxygen in the alveoli. A more common form of the disorder, however, is secondary or toxic methemoglobinemia, caused by exposure to a chemical agent. Substances that cause toxic methemoglobinemia may be strong oxidizers, others may interfere with the enzymatic function of the red blood cells, and still others may block the return of methemoglobin molecules to hemoglobin. In any event, a hemoglobin molecule that has been oxidized to methemoglobin is no longer a viable oxygen transporter in the bloodstream. The result is a form of anemia. Another effect is that hemoglobin molecules still able to transport oxygen to the body tissues bind the oxygen molecules so firmly, because of the effect of methemoglobin on the oxygen dissociation curve, that tissue cells have difficulty in obtaining oxygen. Thus, the presence of methemoglobin in the bloodstream has a double adverse effect and the severity of the condition varies with the concentration of methemoglobin.
Fundamental Aspects of Nitrates in Groundwater
Published in Larry W. Canter, in Groundwater, 2019
Methemoglobinemia refers to an effect in which hemoglobin is oxidized to methemoglobin. When amounts of methemoglobin in blood increase, oxygen levels in blood dwindle. Cyanosis, the illness of oxygen starvation, results, and that particular cyanosis is referred to as methemoglobinemia (Winneberger, 1982). However, the effects of methemoglobinemia are rapidly reversible; and there are, therefore, no cumulative effects.
Porous polyurethane hydrogels incorporated with CMC for eliminating methylene blue from water
Published in International Journal of Smart and Nano Materials, 2023
Li Wang, Qing Yang, Yong Yang, Kun Luo, Ruqing Bai
With the rapid development of economy and industrial civilization, water contamination has become one of the most serious environmental issue that hazard people’s health and balance of nature [1]. The accumulation of industrial production dyes in water is persistent in the natural environment and it is very difficult to eliminate these micropollutants [2], which pose a great threat to the environment [3]. Methylene blue is a typical cationic dye, which causes not only great harm to the environment but also harmful to the human body, such as nausea, shock, and potential cancer risk [4]. This dye causes eye burns, breathing disorders, heart rate increases, shock, cyanosis, jaundice, quadriplegia, tissue necrosis, nausea, vomiting, mental confusion, painful micturition, and methemoglobinemia [5,6].
Oxidation-precipitation of magnetic Fe3O4/AC nanocomposite as a heterogeneous catalyst for electro-Fenton treatment
Published in Chemical Engineering Communications, 2020
Pegah Nazari, Neda Askari, Shahrbanoo Rahman Setayesh
The treatment of the agricultural and industrial effluents which are containing toxic and low or non-biodegradable compounds has become the most challenging issue in the environmental protection science. It is necessary to eliminate these hazardous compounds completely before discharging them into the environment. A considerable portion of water pollutants is organic compounds. The phenolic pollutants are removed hardly due to their high stability. Catechol is a phenol-derived compound with high stability and toxicity. This aromatic compound is mostly utilized as a precursor to flavors, fragrances, and pesticides (Cavalieri et al., 2002). Catechol caused some diseases such as methemoglobinemia, DNA disruption, cyanosis, and death (Cavalieri and Rogan, 2004). Regarding the harmful impact of catechol on human health, an innovative and effective method is required before discharging it into the water resources. The organic chemicals are not remediated effectively by conventional wastewater treatments, due to their drawbacks like time-consuming, inefficiency, creating more toxic intermediates or products, and the need for secondary remediation process. These traditional techniques are categorized as adsorption, photocatalysis, sonochemical, ozonation, and biodegradation (Huang et al., 2017; Alam et al., 2018; Chadi et al., 2018; Ren et al., 2018; Yang et al., 2018).
Evaluating groundwater nitrate and other physicochemical parameters of the arid and semi-arid district of DI Khan by multivariate statistical analysis
Published in Environmental Technology, 2023
Asif Khan, Muhammad Naeem, Ivar Zekker, Muhammad Balal Arian, Greg Michalski, Abbas Khan, Nasrullah Shah, Syed Zeeshan, Hameed ul Haq, Fazle Subhan, Muhammad Ikram, Muhammad Ishaq Ali Shah, Idrees Khan, Luqman Ali Shah, Muhammad Zahoor, Amama Khurshed
Idiopathic causes by nitrates are more common in younger children (under 26 weeks). There has been determined decreased cytochrome b5 reductase quantities in red blood cells after exposure to nitrates [30]. Whenever these patients acquire significant metabolic acidification as a result of diarrhoea and exhaustion, methaemoglobinemia can occur[31]. An important hazardous element for causing newborn methemoglobinemia is the use of nitrate-contaminated drinking water. As a result, newborns have a strange blue-grey skin tone and, based on the intensity of childhood disease, it may become restless or lethargic. If the illness is not diagnosed and treated promptly, it can quickly progress to coma and mortality[32].