Dietary supplements and food fortification
Geoffrey P. Webb in Nutrition, 2019
Babies born prematurely before their lungs are fully developed often need mechanical ventilation and/or an oxygen-enriched atmosphere. Excess oxygen exposure can cause oxygen toxicity which may lead to lung damage (bronchopulmonary dysplasia), eye damage (retinopathy of prematurity) and even brain damage. These conditions have often been attributed to damage caused by excess oxygen free radicals and have even been classed as a single disease “oxygen radical disease in neonatology”. Neonatal units now try to regulate the oxygen given to premature and sick babies so as to try and get a balance between the benefits and harm of extra oxygen. Giving an antioxidant, like vitamin E would seem like a logical preventative measure if these conditions are really caused by oxidative damage. A meta-analysis of 26 clinical trials suggested that giving pharmacological doses of vitamin E to very low birthweight babies may have beneficial effects but is not without risks especially if high intravenous doses are used. Despite the general belief that antioxidant systems are not fully developed in premature babies, WHO guidelines do not support routine supplementation with vitamin E.
O
Anton Sebastian in A Dictionary of the History of Medicine, 2018
Oxygen [Greek: oxys, sour + gentian, to produce] John Mayow (1640–1679), an English chemist, realized that when substances burnt in air a chemical union with a constituent of the atmosphere took place. He called this gas ‘igneo aereum’ or ‘spiritus nitro-aerius’. His insight into combustion was not accepted, and the erroneous theory of German chemist Georg Ernst Stahl (1660–1734), that when substances burnt they used an essence within them called phlogiston, became accepted. Phlogiston theory was held for over a hundred years until Joseph Priestley (1733–1804), an English chemist, obtained pure oxygen by heating a metal oxide. He called the gas ‘dephologisticated air’ in 1774. Oxygen was discovered independently by a Swedish apothecary, Carl Wilhelm Scheele (1742–1786), in the same year. In 1775 Antoine Laurent Lavoisier (1743–1794) named the substance responsible for combustion ‘acidifying principle’ which, in Greek was ‘oxygine principle’, hence its present name. The atomic weight was calculated at 16 by London chemist, William Odling (1829–1921), who qualified as a physician from London University in 1851. The first commercial preparation of oxygen using fractional distillation of air was achieved by Karl von Linde (1842–1934) in 1895.
Holistic view of health and illness
Mabel Aghadiuno, Christopher Dowrick in Soul Matters – The Spiritual Dimension within Healthcare, 2017
Two particular atoms illustrate the idea of holism nicely. A water molecule is much more than the sum of its parts – two hydrogen atoms and one oxygen atom. The oxygen and hydrogen atoms are the components of invisible gases. Oxygen is colourless, tasteless and odourless but we could not live without it. Hydrogen is also imperceptible. Together the two gases combine to form water: a vital, visible liquid, something more much more than the individual constituents. Water quenches thirst, is the gardener’s dream when its advent is timely and brings joy and laughter in the swimming pool. Culturally and mythologically over the ages it has been and still is the symbol to many of expiation and purification. Water is also therapeutic and Napoleon Bonaparte once said, ‘Water, air, and cleanness are the chief articles in my pharmacy.’
PEG-conjugated bovine haemoglobin enhances efficiency of chemotherapeutic agent doxorubicin with alleviating DOX-induced splenocardiac toxicity in the breast cancer
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2023
Bingting Li, Jun Zhang, Ning Ma, Weidan Li, Guoxing You, Gan Chen, Lian Zhao, Quan Wang, Hong Zhou
Based on the in vitro data, it is anticipated that PCBH could increase the DOX's effectiveness in eliminating tumours with severe hypoxia. The well-known primary bio-barrier for chemotherapy—the hypoxic tumour microenvironment (TME)—could upregulate HIF-1α in tumour cells, which is well-reported to cause the chemotherapeutic drugs’ induction of multidrug resistance (MDR) and is frequently used to confirm the hypoxia in tumours [43]. To determine the reduction in tumour hypoxia by using PCBH's capacity for O2 delivery and transport, the changes in fluorescent intensity of O2 contained in tumours were measured in two distinct groups, NS (150 μl) and PCBH (150 mg/kg, 150 μl) using the VISISENS fluorescence imaging system. Further calculations of oxygen saturation were made throughout time. As demonstrated in Figure 4(A,B), when NS was administered to a blank control, the oxygen saturation showed a brief increase; the peak occurred at 2 h, and it quickly returned to baseline. It was clear that oxygen saturation increased significantly and remained elevated from 2 h to 8 h, with a minor reduction. It is confirmed that PCBH could significantly and permanently reduce tumour hypoxia while raising the oxygen saturation of tumour tissue.
Neuroprotective effects of natural compounds on neurotoxin-induced oxidative stress and cell apoptosis
Published in Nutritional Neuroscience, 2022
Bo Chen, Jingjing Zhao, Rui Zhang, Lingling Zhang, Qian Zhang, Hao Yang, Jing An
Reactive oxygen and nitrogen species are produced by several endogenous and exogenous processes. Free radicals are referred to molecular entities or molecular fragments that contain one or more unpaired electrons and are paramagnetic. Most of the free radicals are short-lived, unstable and highly reactive[11]. ROS represent the most important class of free radicals produced in living systems. ROS are generated during aerobic respiration, cellular metabolism, or in response to pathogens defense. Oxygen molecular (O2) has a unique electronic configuration and is a free radical itself. O2 can easily accept a single electron to form O2•−. O2•− is considered to be the main ROS, which can further interact with other molecules to produce more radical species either directly or through enzyme or metal catalyzed processes[12]. The mitochondrial electron transport chain (ETC, respiratory chain) is one of the primary sources of ATP in mammalian cells. ROS are metabolic byproducts of aerobic respiration occurring in the inner membrane of the mitochondria. During energy transduction, O2 is the final acceptor of electrons and protons, and it is reduced by four electrons to produce two molecules of water (H2O). Some of the redox centers in the ETC may leak electrons to O2, partially reducing this molecule to O2−• and then to H2O2 and HO•[13].
The rise of mucormycosis in Covid-19 patients in India
Published in Expert Review of Anti-infective Therapy, 2022
Oxygen is used in industries for several purposes including welding, cutting, and other chemical and combustion applications. Given the dire need for oxygen in India, it is not surprising to note that huge quantity of industrial oxygen was diverted for medical use, and the oxygen cylinders used in industries were used to transport the oxygen to hospitals and health facilities. According to the WHO, medical-use oxygen is very different from industrial oxygen in purity and quality, and that the production, storage, and distribution processes involved with industrial oxygen could result in contamination [14]. For example, the industrial oxygen cylinders are inappropriate for medical use as these can be contaminated with impurities as a result of use of unclean equipment, unhygienic storage, and may be prone to micro leaks. Therefore, industrial oxygen cylinders need to be upgraded for medical use by undergoing a process of deep cleaning and disinfection, sealing micro leaks, replacing valves, and ensuring they are free of any contamination before their use for medical purposes. Given the acute shortage of oxygen on one hand, and the time and costs involved with this process on the other, it is likely that implementation of protocols for conversion of industrial oxygen cylinders to medical use at various levels was not adhered to thus enhancing the risks of mucormycosis. This is more so as there is currently no law that can make anyone accountable.
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