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Anesthesiology Mar 2019Operating room fires are rare but devastating events. Guidelines are available for the prevention and management of surgical fires; however, these recommendations are... (Review)
Review
Operating room fires are rare but devastating events. Guidelines are available for the prevention and management of surgical fires; however, these recommendations are based on expert opinion and case series. The three components of an operating room fire are present in virtually all surgical procedures: an oxidizer (oxygen, nitrous oxide), an ignition source (i.e., laser, "Bovie"), and a fuel. This review analyzes each fire ingredient to determine the optimal clinical strategy to reduce the risk of fire. Surgical checklists, team training, and the specific management of an operating room fire are also reviewed.
Topics: Electrocoagulation; Fires; Gas Scavengers; Humans; Operating Rooms; Oxygen; Plastic Surgery Procedures
PubMed: 30664060
DOI: 10.1097/ALN.0000000000002598 -
Swiss Dental Journal 2015«Laughing gas» (nitrous oxide N2O) has analgesic and sedative properties and is commonly used in dentistry because of its many advantages (ease of use, dose titration,...
«Laughing gas» (nitrous oxide N2O) has analgesic and sedative properties and is commonly used in dentistry because of its many advantages (ease of use, dose titration, rapid onset, lack of prolonged effects, both analgetic and anxiolytic effects). However, nitrous oxide may cause vitamin B12 deficiency, has abuse liability, and occupational exposure has been associated with infertility, spontaneous abortion, blood dyscrasias, and neurologic deficits. Scavenger systems are recommended to minimize exposure and personnel should be informed about the potential risks.
PubMed: 26470605
DOI: No ID Found -
Frontiers in Cellular Neuroscience 2019Although the cochlear vascular supply (stria vascularis) is designed to block to certain compounds and molecules, it must enable gas exchange to survive. The inner ear... (Review)
Review
Although the cochlear vascular supply (stria vascularis) is designed to block to certain compounds and molecules, it must enable gas exchange to survive. The inner ear capillaries must deliver oxygen and remove carbon dioxide for the cochlea to function. These gases diffuse through tissues across a concentration gradient to reach the desired target. Tight junctions or the endothelial basement membrane do not impede them. Therefore, gases that can diffuse into the inner ear are attractive as therapeutic agents. The two gases most often used in this way are oxygen and hydrogen, although carbon dioxide, ozone, and argon have also been investigated. Typically, oxygen is delivered as hyperbaric oxygen (HBO) (oxygen at pressure higher than atmospheric) to provide increased oxygen levels to the inner ear. This not only relieves hypoxia, but also has anti-inflammatory and other biochemical effects. HBO is used clinically to treat idiopathic sudden sensorineural hearing loss, and both animal and human studies suggest it may also assist recovery after acute acoustic trauma. Laboratory studies suggest hydrogen works as a free radical scavenger and reduces the strong oxidants hydroxyl radicals and peroxynitrite. It also has anti-apoptotic effects. Because of its anti-oxidant and anti-inflammatory effects, it has been studied as a treatment for ototoxicity and shows benefit in an animal model of cisplatinum toxicity. Gas diffusion offers an effective way to provide therapy to the inner ear, particularly since some gases (oxygen, hydrogen, carbon dioxide, ozone, argon) have important therapeutic effects for minimizing cochlear damage.
PubMed: 31068792
DOI: 10.3389/fncel.2019.00155 -
Gastroenterology Mar 2021Inflammation in the gastrointestinal tract may lead to the development of cancer. Dicarbonyl electrophiles, such as isolevuglandins (isoLGs), are generated from lipid...
BACKGROUND & AIMS
Inflammation in the gastrointestinal tract may lead to the development of cancer. Dicarbonyl electrophiles, such as isolevuglandins (isoLGs), are generated from lipid peroxidation during the inflammatory response and form covalent adducts with amine-containing macromolecules. Thus, we sought to determine the role of dicarbonyl electrophiles in inflammation-associated carcinogenesis.
METHODS
The formation of isoLG adducts was analyzed in the gastric tissues of patients infected with Helicobacter pylori from gastritis to precancerous intestinal metaplasia, in human gastric organoids, and in patients with colitis and colitis-associated carcinoma (CAC). The effect on cancer development of a potent scavenger of dicarbonyl electrophiles, 5-ethyl-2-hydroxybenzylamine (EtHOBA), was determined in transgenic FVB/N insulin-gastrin (INS-GAS) mice and Mongolian gerbils as models of H pylori-induced carcinogenesis and in C57BL/6 mice treated with azoxymethane-dextran sulfate sodium as a model of CAC. The effect of EtHOBA on mutations in gastric epithelial cells of H pylori-infected INS-GAS mice was assessed by whole-exome sequencing.
RESULTS
We show increased isoLG adducts in gastric epithelial cell nuclei in patients with gastritis and intestinal metaplasia and in human gastric organoids infected with H pylori. EtHOBA inhibited gastric carcinoma in infected INS-GAS mice and gerbils and attenuated isoLG adducts, DNA damage, and somatic mutation frequency. Additionally, isoLG adducts were elevated in tissues from patients with colitis, colitis-associated dysplasia, and CAC as well as in dysplastic tumors of C57BL/6 mice treated with azoxymethane-dextran sulfate sodium. In this model, EtHOBA significantly reduced adduct formation, tumorigenesis, and dysplasia severity.
CONCLUSIONS
Dicarbonyl electrophiles represent a link between inflammation and somatic genomic alterations and are thus key targets for cancer chemoprevention.
Topics: Animals; Benzylamines; Cell Nucleus; Cell Transformation, Neoplastic; Colitis-Associated Neoplasms; Disease Models, Animal; Epithelial Cells; Gastric Mucosa; Gastritis; Gerbillinae; Helicobacter Infections; Helicobacter pylori; Humans; Lipids; Metaplasia; Mice; Mice, Transgenic; Organoids; Precancerous Conditions; Stomach Neoplasms
PubMed: 33189701
DOI: 10.1053/j.gastro.2020.11.006 -
Acid Scavenger Free Synthesis of Oligo(Poly(Ethylene Glycol) Fumarate) Utilizing Inert Gas Sparging.Tissue Engineering. Part C, Methods May 2021The macromolecule oligo(poly(ethylene glycol) fumarate) (OPF) exhibits promising attributes for creating suitable three-dimensional hydrogel environments to study cell...
The macromolecule oligo(poly(ethylene glycol) fumarate) (OPF) exhibits promising attributes for creating suitable three-dimensional hydrogel environments to study cell behavior, deliver therapeutics, and serve as a degradable, nonfouling material. However, traditional synthesis techniques are time consuming, contain salt contaminants, and generate significant waste. These issues have been overcome with an alternative, one-pot approach that utilizes inert gas sparging. Departing from previous synthetic schemes that require acid scavengers, inert gas sparging removes byproducts , eliminating significant filtration and postprocessing steps, while allowing a more uniform product. Characterized by nuclear magnetic resonance, gel permeation chromatography, and differential scanning calorimetry, nitrogen sparge synthesis yields an OPF product with greater polymer length than traditional acid scavenger synthesis methods. Furthermore, nitrogen-sparged OPF readily crosslinks using either ultraviolet or thermal initiator methods with or without the addition of short-chain diacrylate units, allowing for greater tunability in hydrogel properties with little to no cytotoxicity. Overall, inert gas sparging provides a longer chain and cleaner polymer product for hydrogel material studies while maintaining degradable characteristics. Impact statement Using nitrogen sparging, we have demonstrated that oligo(poly(ethylene glycol) fumarate) (OPF) can be produced with decreased postprocessing, increased product purity, greater oligomerization, and cell viability. These properties lead to greater tunability in mechanical properties and a more versatile hydrogel for biomedical applications. The simplification of synthesis and elimination of impurities will expand the utility of OPF as a degradable hydrogel for cell culture, tissue engineering, regenerative medicine, and therapeutic delivery, among other applications.
Topics: Cell Survival; Fumarates; Hydrogels; Polyethylene Glycols; Tissue Engineering
PubMed: 33765836
DOI: 10.1089/ten.TEC.2021.0027 -
Tidsskrift For Den Norske Laegeforening... Nov 2012Perinatal asphyxia can cause serious illness or death. By taking steps in the «latent phase», which occurs 6-24 hours after the hypoxic event, the neurological damage... (Review)
Review
BACKGROUND
Perinatal asphyxia can cause serious illness or death. By taking steps in the «latent phase», which occurs 6-24 hours after the hypoxic event, the neurological damage caused by perinatal asphyxia can be limited. We wish to present a selection of such measures that are either established treatment today or that appear promising.
METHOD
We searched in the Medline and Cochrane Library databases for options for treating perinatal asphyxia.
RESULTS
An overwhelming number of potential treatments were identified. From among them we selected 44 indexed, peer-reviewed original articles in English on strategies for neuroprotective treatment after perinatal asphyxia. The treatments target different cellular mechanisms that cause neurological damage following perinatal asphyxia. In randomised clinical trials, only hypothermia treatment has improved the long-term outcome for newborns with perinatal asphyxia. Xenon gas, erythropoeitin and allopurinol are undergoing clinical testing.
INTERPRETATION
The efficacy of xenon gas, erythropoeitin and allopurinol in combination with the established treatment form of hypothermia must be studied more closely. Antioxidants, stem cell treatment and DNA repair mechanisms can pave the way for new opportunities in the future.
Topics: Allopurinol; Anesthetics, Inhalation; Asphyxia Neonatorum; Combined Modality Therapy; Erythropoietin; Free Radical Scavengers; Humans; Hypothermia, Induced; Infant, Newborn; Neuroprotective Agents; Time Factors; Xenon
PubMed: 23160590
DOI: 10.4045/tidsskr.12.0120 -
Medical Gas Research 2016Molecular hydrogen (H) medicine research has flourished since a landmark publication in that revealed the antioxidant and cytoprotective effects of hydrogen gas in a... (Review)
Review
Molecular hydrogen (H) medicine research has flourished since a landmark publication in that revealed the antioxidant and cytoprotective effects of hydrogen gas in a focal stroke model. Emerging evidence has consistently demonstrated that molecular hydrogen is a promising therapeutic option for a variety of diseases and the underlying comprehensive mechanisms is beyond pure hydroxyl radicals scavenging. The non-toxicity at high concentrations and rapid cellular diffusion features of molecular hydrogen ensure the feasibility and readiness of its clinical translation to human patients.
PubMed: 28217294
DOI: 10.4103/2045-9912.196904 -
Royal Society Open Science Jun 20227-O-Galloyltricetifavan (), a natural flavonoid, is isolated from the leaves of . The compound exhibits a variety of biological activities. This study details the...
7-O-Galloyltricetifavan (), a natural flavonoid, is isolated from the leaves of . The compound exhibits a variety of biological activities. This study details the evaluation of the HOO antiradical activity of by quantum chemistry calculations. The HOO trapping activity of in the gas phase (reference state) was discovered to follow the formal hydrogen transfer mechanism with a rate constant of = 4.58 × 10 M s. In physiological environments, is predicted to be an excellent HOO radical scavenger with = 2.65 × 10 and 1.40 × 10 M s in water and pentyl ethanoate solvents, respectively. The HOO antiradical activity of in water at physiological pH is approximately 2000 times that of Trolox and substantially higher than that of other well-known natural antioxidants such as trans-resveratrol or ascorbic acid. Thus, is an excellent natural antioxidant in polar environments.
PubMed: 35754988
DOI: 10.1098/rsos.211906 -
Journal of Visualized Experiments : JoVE Jan 2012Cigarette smoking is associated with human cancers. It has been reported that most of the lung cancer deaths are caused by cigarette smoking (5,6,7,12). Although tobacco...
Cigarette smoking is associated with human cancers. It has been reported that most of the lung cancer deaths are caused by cigarette smoking (5,6,7,12). Although tobacco tars and related products in the particle phase of cigarette smoke are major causes of carcinogenic and mutagenic related diseases, cigarette smoke contains significant amounts of free radicals that are also considered as an important group of carcinogens(9,10). Free radicals attack cell constituents by damaging protein structure, lipids and DNA sequences and increase the risks of developing various types of cancers. Inhaled radicals produce adducts that contribute to many of the negative health effects of tobacco smoke in the lung(3). Studies have been conducted to reduce free radicals in cigarette smoke to decrease risks of the smoking-induced damage. It has been reported that haemoglobin and heme-containing compounds could partially scavenge nitric oxide, reactive oxidants and carcinogenic volatile nitrosocompounds of cigarette smoke(4). A 'bio-filter' consisted of haemoglobin and activated carbon was used to scavenge the free radicals and to remove up to 90% of the free radicals from cigarette smoke(14). However, due to the cost-ineffectiveness, it has not been successfully commercialized. Another study showed good scavenging efficiency of shikonin, a component of Chinese herbal medicine(8). In the present study, we report a protocol for introducing common natural antioxidant extracts into the cigarette filter for scavenging gas phase free radicals in cigarette smoke and measurement of the scavenge effect on gas phase free radicals in mainstream cigarette smoke (MCS) using spin-trapping Electron Spin Resonance (ESR) Spectroscopy(1,2,14). We showed high scavenging capacity of lycopene and grape seed extract which could point to their future application in cigarette filters. An important advantage of these prospective scavengers is that they can be obtained in large quantities from byproducts of tomato or wine industry respectively(11,13).
Topics: Antioxidants; Carotenoids; Electron Spin Resonance Spectroscopy; Filtration; Free Radical Scavengers; Grape Seed Extract; Lycopene; Smoke; Nicotiana
PubMed: 22230844
DOI: 10.3791/3406 -
Medical Gas Research Mar 2016Up to now, over 1,000 experimental treatments found in cells and rodents have been difficult to translate to human ischemic stroke. Since ischemia and reperfusion, two... (Review)
Review
Up to now, over 1,000 experimental treatments found in cells and rodents have been difficult to translate to human ischemic stroke. Since ischemia and reperfusion, two separate stages of ischemic stroke, have different pathophysiological mechanisms leading to brain injury, a combination of protective agents targeting ischemia and reperfusion respectively may obtain substantially better results than a single agent. Normobaric hyperoxia (NBO) has been shown to exhibit neuro- and vaso-protective effects by improving tissue oxygenation when it is given during ischemia, however the effect of NBO would diminish when the duration of ischemia and reperfusion was extended. Therefore, during reperfusion drug treatment targeting inflammation, oxidative stress and free radical scavenger would be a useful adjuvant to extend the therapeutic window of tissue plasminogen activator, the only United States Food and Drug Administration (FDA) approved treatment for acute ischemic stroke. In this review, we discussed the neuro- and vaso-protective effects of NBO and recent finding of combining NBO with other drugs.
PubMed: 27826421
DOI: 10.4103/2045-9912.179343