691,782 results match your criteria oxygen production

Characteristics and predictors for silent hypoxemia in a cohort of hospitalized COVID-19 patients.

Auton Neurosci 2021 Jul 17;235:102855. Epub 2021 Jul 17.

Department of Neurology and Psychiatry, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico. Electronic address:

Background: An intriguing feature recently unveiled in some COVID-19 patients is the "silent hypoxemia" phenomenon, which refers to the discrepancy of subjective well-being sensation while suffering hypoxia, manifested as the absence of dyspnea.

Objective: To describe the clinical characteristics and predictors of silent hypoxemia in hospitalized COVID-19 patients.

Methods: We conducted a prospective cohort study including consecutive hospitalized adult (≥ 18 years) patients with confirmed COVID-19 presenting to the emergency department with oxygen saturation (SpO2) ≤ 80% on room air from March 15 to June 30, 2020. Read More

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Biodegradable and re-usable sponge materials made from chitin for efficient removal of microplastics.

J Hazard Mater 2021 Jul 8;420:126599. Epub 2021 Jul 8.

Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China. Electronic address:

Microplastics have attracted widespread attention due to their detrimental effects on organisms, and their efficient removal poses great challenges, especially those smaller than 3 µm that are more harmful for aquatic biota. Herein, the chitin based sponges with interconnected pores, excellent elasticity and mechanical durability were fabricated and composed with graphene oxide (GO) and oxygen-doped carbon nitride (O-CN). The chitin based sponges could effectively remove different functionalized microplastics (~1 µm) at pH 6-8, including carboxylate-modified polystyrene (PS-COOH), amine-modified polystyrene (PS-NH), and polystyrene (PS). Read More

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Oxidative stress and DNA damage induced by trifloxystrobin on earthworms (Eisenia fetida) in two soils.

Sci Total Environ 2021 Jul 17;797:149004. Epub 2021 Jul 17.

College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, 61 Daizong Road, Taian 271018, China. Electronic address:

Trifloxystrobin is a new type of fungicide, which is extensively used due to its excellent antifungal activity. In this study, oxidative stress and DNA damage induced by trifloxystrobin exposure was evaluated using Eisenia fetida at subchronic toxicity concentrations in artificial soil and brown soil (0.1-2. Read More

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N,O-codoped carbon spheres with uniform mesoporous entangled CoO nanoparticles as a highly efficient electrocatalyst for oxygen reduction in a Zn-air battery.

J Colloid Interface Sci 2021 Jul 10;604:746-756. Epub 2021 Jul 10.

State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, PR China. Electronic address:

Highly efficient electrochemical catalysts for oxygen reduction reactions (ORRs) are urgently needed for various energy conversion and storage devices to overcome sluggish ORR kinetics. Here, N,O-codoped carbon spheres with uniform mesopores and a high specific surface area were used as supports for decorating CoO nanoparticles via a facile immersion route. In addition to the benefit of ions and gas mass transfer, the abundant mesopores present in the three-dimensional (3D) carbon spheres also confine and isolate the CoO nanoparticles growing in it, which help to provide rich CoO active sites. Read More

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Enhanced activity promoted by amorphous metal oxyhydroxides on CeO for alkaline oxygen evolution reaction.

J Colloid Interface Sci 2021 Jul 7;604:719-726. Epub 2021 Jul 7.

College of Materials Science and Engineering, Sichuan University, Chengdu 610064, Sichuan, China. Electronic address:

Herein, we demonstrate a direct growth of amorphous metal oxyhydroxide (AMO) attached on CeO by a galvanic replacement mechanism as advanced oxygen evolution reaction (OER) catalyst. In this unique structure, the CeO substrate not only offers high specific surface area for the formation of AMO, but also provides high conductivity, guaranteeing the promoted electron transfer for the catalytic reaction. In addition, the AMO on the surface of the CeO exposes abundant active sites for the OER. Read More

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Promising potential of boron compounds against Glioblastoma: In Vitro antioxidant, anti-inflammatory and anticancer studies.

Neurochem Int 2021 Jul 19;149:105137. Epub 2021 Jul 19.

Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, London, SE1 9RT, UK; Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, SE-17121, Sweden. Electronic address:

Glioblastoma (GB) is the most common and aggressive primary malignant astrocytoma correlated with poor patient survival. There are no curative treatments for GB, and it becomes resistant to chemotherapy, radiation therapy, and immunotherapy. Resistance in GB cells is closely related to their states of redox imbalance, and the role of reactive oxygen species and its impact on cancer cell survival is still far from elucidation. Read More

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Gas exchange and dive behaviour in the diving beetle Platynectes decempunctatus (Coleoptera: Dytiscidae).

J Insect Physiol 2021 Jul 19:104286. Epub 2021 Jul 19.

Department of Ecology and Evolutionary Biology, School of Biological Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.

Many aquatic insects use bubbles on the body surface to store and supply O for their dives. There are two types of bubbles: air stores, which store O gained from air at the surface, and gas gills that allow passive extraction of O from water. Many insects using air stores and gas gills return to the surface to replenish their bubbles and, therefore, their requirement for O influences dive behaviour. Read More

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Surface-Promoted Evolution of Ru-bda Coordination Oligomers Boosts the Efficiency of Water Oxidation Molecular Anodes.

J Am Chem Soc 2021 Jul 22. Epub 2021 Jul 22.

Institute of Chemical Research of Catalonia (ICIQ). Barcelona Institute of Science and Technology (BIST), Avenida Països Catalans 16, 43007 Tarragona, Spain.

A new Ru oligomer of formula {[Ru(bda-κ-NO)(4,4'-bpy)](4,4'-bpy)}, (bda is [2,2'-bipyridine]-6,6'-dicarboxylate and 4,4'-bpy is 4,4'-bipyridine), was synthesized and thoroughly characterized with spectroscopic, X-ray, and electrochemical techniques. This oligomer exhibits strong affinity for graphitic materials through CH-π interactions and thus easily anchors on multiwalled carbon nanotubes (CNT), generating the molecular hybrid material . The latter acts as a water oxidation catalyst and converts to a new species, , during the electrochemical oxygen evolution process involving solvation and ligand reorganization facilitated by the interactions of molecular Ru catalyst and the surface. Read More

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Atomically Precise Dinuclear Site Active toward Electrocatalytic CO Reduction.

J Am Chem Soc 2021 Jul 22. Epub 2021 Jul 22.

National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, PR China.

The development of atomically precise dinuclear heterogeneous catalysts is promising to achieve efficient catalytic performance and is also helpful to the atomic-level understanding on the synergy mechanism under reaction conditions. Here, we report a Ni(dppm)Cl dinuclear-cluster-derived strategy to a uniform atomically precise Ni site, consisting of two Ni-N moieties shared with two nitrogen atoms, anchored on a N-doped carbon. By using synchrotron X-ray absorption spectroscopy, we identify the dynamically catalytic dinuclear Ni structure under electrochemical CO reduction reaction, revealing an oxygen-bridge adsorption on the Ni-N site to form an O-Ni-N structure with enhanced Ni-Ni interaction. Read More

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Impaired muscle oxygen extraction kinetics in cirrhosis - muscle is a major contributor to impaired whole body exercise capacity.

Liver Transpl 2021 Jul 22. Epub 2021 Jul 22.

Department of Biomedical Engineering, University of Alberta, Edmonton, Alberta, Canada.

Reduced exercise tolerance (whole body peak oxygen uptake, VO ) is a hallmark feature of both heart failure (HF) and cirrhosis . By the Fick equation, whole body peak VO is the product of cardiac output (central component) and O extraction (i.e. Read More

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Oils Rich in α-Linolenic Acid or Docosahexaenoic Acid Have Distinct Effects on Plasma Oxylipin and Adiponectin Concentrations and on Monocyte Bioenergetics in Women with Obesity.

J Nutr 2021 Jul 22. Epub 2021 Jul 22.

Department of Food and Human Nutritional Sciences, University of Manitoba, Manitoba, Canada.

Background: Omega-3 fatty acids, including DHA and α-linolenic acid (ALA), are proposed to improve metabolic health by reducing obesity-associated inflammation. Their effects are mediated in part by conversion to oxylipins. ALA is relatively understudied, and direct comparisons to other omega-3 fatty acids are limited. Read More

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A mathematical investigation into the uptake kinetics of nanoparticles in vitro.

PLoS One 2021 22;16(7):e0254208. Epub 2021 Jul 22.

Department for Applied Mathematics, Liverpool John Moores University, Liverpool, United Kingdom.

Nanoparticles have the potential to increase the efficacy of anticancer drugs whilst reducing off-target side effects. However, there remain uncertainties regarding the cellular uptake kinetics of nanoparticles which could have implications for nanoparticle design and delivery. Polymersomes are nanoparticle candidates for cancer therapy which encapsulate chemotherapy drugs. Read More

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Spatially resolved analysis of Pseudomonas aeruginosa biofilm proteomes measured by laser ablation sample transfer.

PLoS One 2021 22;16(7):e0250911. Epub 2021 Jul 22.

Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois, United States of America.

Heterogeneity in the distribution of nutrients and oxygen gradients during biofilm growth gives rise to changes in phenotype. There has been long term interest in identifying spatial differences during biofilm development including clues that identify chemical heterogeneity. Laser ablation sample transfer (LAST) allows site-specific sampling combined with label free proteomics to distinguish radially and axially resolved proteomes for Pseudomonas aeruginosa biofilms. Read More

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Design, Synthesis, and Biological Evaluation of Organic Nitrite (NO) Donors as Potential Anticerebral Ischemia Agents.

J Med Chem 2021 Jul 22. Epub 2021 Jul 22.

State Key Laboratory of Natural Medicines, Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing 210009, P.R. China.

The treatment of ischemic stroke (IS) remains a big challenge in clinics, and it is urgently needed to develop novel, safe, and effective medicines against IS. Here, we report the design, synthesis, and biological evaluation of organic NO donors as potential agents for the treatment of IS. The representative compound was able to slowly generate low concentrations of NO by reaction with a thiol-containing nucleophile, and the NO was selectively converted into NO under ischemic/hypoxia conditions to protect primary rat neurons from oxygen-glucose deprivation and recovery (OGD/R)-induced cytotoxicity by enhancing the Nrf2 signaling and activating the NO/cGMP/PKG pathway. Read More

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Modular Platform for the Development of Recombinant Hemoglobin Scavenger Biotherapeutics.

Mol Pharm 2021 Jul 22. Epub 2021 Jul 22.

Division of Internal Medicine, Universitätsspital and University of Zurich, Zurich 8091, Switzerland.

Cell-free hemoglobin (Hb) is a driver of disease progression in conditions with intravascular or localized hemolysis. Genetic and acquired anemias or emergency medical conditions such as aneurysmal subarachnoid hemorrhage involve tissue Hb exposure. Haptoglobin (Hp) captures Hb in an irreversible protein complex and prevents its pathophysiological contributions to vascular nitric oxide depletion and tissue oxidation. Read More

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Highly Stable Silica-Coated Bismuth Nanoparticles Deliver Tumor Microenvironment-Responsive Prodrugs to Enhance Tumor-Specific Photoradiotherapy.

J Am Chem Soc 2021 Jul 22. Epub 2021 Jul 22.

CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics and National Center for Nanoscience and Technology, Chinese Academy of Sciences, Beijing 100049, P. R. China.

Radiosensitizers are agents capable of amplifying injury to tumor tissues by enhancing DNA damage and fortifying production of radical oxygen species (ROS). The use of such radiosensitizers in the clinic, however, remains limited by an insufficient ability to differentiate between cancer and normal cells and by the presence of a reversible glutathione system that can diminish the amount of ROS generated. Here, to address these limitations, we design an HO-responsive prodrug which can be premixed with lauric acid (melting point ∼43 °C) and loaded around the surface of silica-coated bismuth nanoparticles (BSNPs) for cancer-specific photoradiotherapy. Read More

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Transforming C Molecules into Polyhedral Carbon Micro-Nano Shells for Electrochemically Producing HO in Neutral Electrolytes.

ACS Appl Mater Interfaces 2021 Jul 22. Epub 2021 Jul 22.

CAS Key Laboratory of Design and Assembly of Functional Nanostructures, and Fujian Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China.

The electrochemical production of hydrogen peroxide (HO) via the two-electron oxygen reduction reaction (ORR) can realize the customer-oriented onsite synthesis of HO in a green and sustainable method. The ongoing challenge that needs to be solved is the fabrication of robust electrocatalysts of excellent performance. In this work, C was selected as a precursor due to its uniform structure and abundant pentagon rings. Read More

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Raman Imaging Reveals Accumulation of Hemoproteins in Plaques from Alzheimer's Diseased Tissues.

ACS Chem Neurosci 2021 Jul 22. Epub 2021 Jul 22.

Laboratoire de Bioélectrochimie et Spectroscopie, UMR 7140, Chimie De La Matière Complexe, Université de Strasbourg-CNRS, 4 Rue Blaise Pascal, 67081 Strasbourg, France.

Hemes have been suggested to play a central role in Alzheimer's disease since they show high peroxidase reactivity when bound to amyloid β peptides, leading to the production of reactive oxygen species. Here we used Fourier transform infrared and Raman imaging on Alzheimer's diseased mice and human brain tissue. Our finding suggests the accumulation of hemes in the senile plaques of both murine and human samples. Read More

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Extracorporeal membrane oxygenation (ECMO) for critically ill patients with coronavirus disease 2019 (COVID-19): A retrospective cohort study.

J Card Surg 2021 Jul 22. Epub 2021 Jul 22.

Department of Cardiology, Chinese PLA General Hospital, Beijing, China.

Purpose: The role of extracorporeal membrane oxygenatio (ECMO) for rescue therapy of respiratory failure in critically ill coronavirus disease 2019 (COVID-19) patients remains controversial. We aimed to evaluate the clinical outcomes of ECMO in the treatment of COVID-19 compared with conventional ventilation support.

Methods: In this retrospective cohort study, data were collected on extremely critical patients with COVID-19 from January 2020 to March 2020 in intensive care unit of a hospital in charge by national rescue team in Wuhan, China, the epicenter of pandemic. Read More

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Accelerated Redox Reaction of Hydrogen Peroxide by Employing Locally Concentrated State of Copper Catalysts on Polymer Chain.

Macromol Rapid Commun 2021 Jul 22:e2100274. Epub 2021 Jul 22.

Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo, 162-8601, Japan.

Copper complexes act as catalysts for redox reactions to generate reactive oxygen species that destroy biomolecules and, therefore, are utilized to design drugs including antitumor and antibacterial medicines. Especially, catalytic reaction for hydrogen peroxide decomposition is important because it includes the process for generating highly toxic hydroxyl radical, i.e. Read More

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Methods for Heterologous Overproduction of Fe-S Proteins.

Methods Mol Biol 2021 ;2353:69-78

Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.

Proteins carrying iron-sulfur ([Fe-S]) clusters are critical to the basic metabolism of all organisms. Structural and biochemical investigations of many such [Fe-S] cluster proteins depend on recombinant overproduction using heterologous bacterial hosts such as Escherichia coli . Here, we describe a detailed procedure for the overproduction and purification of two oxygen-sensitive component proteins of the dark-operative protochlorophyllide oxidoreductase (DPOR) complex. Read More

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January 2021

Chronic Exposure to Hypoxia Inhibits Myelinogenesis and Causes Motor Coordination Deficits in Adult Mice.

Neurosci Bull 2021 Jul 22. Epub 2021 Jul 22.

Department of Histology and Embryology, Chongqing Key Laboratory of Neurobiology, Brain and Intelligence Research Key Laboratory of Chongqing Education Commission, Third Military Medical University, Chongqing, 400038, China.

Exposure to chronic hypoxia is considered to be a risk factor for deficits in brain function in adults, but the underlying mechanisms remain largely unknown. Since active myelinogenesis persists in the adult central nervous system, here we aimed to investigate the impact of chronic hypoxia on myelination and the related functional consequences in adult mice. Using a transgenic approach to label newly-generated myelin sheaths (NG2-CreER; Tau-mGFP), we found that myelinogenesis was highly active in most brain regions, such as the motor cortex and corpus callosum. Read More

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Theoretical evaluation of a novel method for producing fluorine-18 for Positron-emission-tomography (PET) applications utilizing the He(d,p)He reaction.

Phys Eng Sci Med 2021 Jul 22. Epub 2021 Jul 22.

Department of Radiation Oncology, Sir Charles Gairdner Hospital, Perth, WA, Australia.

A novel method of producing fluorine-18 for Positron emission tomography (PET) scan applications is evaluated theoretically. The method is based upon the He(d,p)He nuclear reaction from which the protons produced are used to produce fluorine-18 via the O(p,n)F reaction. The potential advantage of such a system over cyclotron-based production is of lower input beam energy, which may lower the cost of the system and potentially allow for onsite production. Read More

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Urgent surgery for COVID-19-positive pediatric patient.

JA Clin Rep 2021 Jul 22;7(1):57. Epub 2021 Jul 22.

Department of Anesthesiology and Critical Care Medicine, Children's Hospital Los Angeles, University of Southern California, 4650 Sunset Blvd, Los Angeles, CA, 90027, USA.

Background: We present a case of COVID-19-positive pediatric patient for urgent urological surgery by spinal anesthesia to avoid aerosolizing procedure.

Case Presentation: A 12-year-old, COVID-19-positive boy presented for urgent wound incision and drainage at the circumcision site. Our anesthetic plan consisted of spinal anesthesia with sedation. Read More

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Noninvasive ventilation vs. high-flow nasal cannula oxygen for preoxygenation before intubation in patients with obesity: a post hoc analysis of a randomized controlled trial.

Ann Intensive Care 2021 Jul 22;11(1):114. Epub 2021 Jul 22.

Médecine Intensive Réanimation, CHU de Poitiers, Poitiers, France.

Background: Critically ill patients with obesity may have an increased risk of difficult intubation and subsequent severe hypoxemia. We hypothesized that pre-oxygenation with noninvasive ventilation before intubation as compared with high-flow nasal cannula oxygen may decrease the risk of severe hypoxemia in patients with obesity.

Methods: Post hoc subgroup analysis of critically ill patients with obesity (body mass index ≥ 30 kg·m) from a multicenter randomized controlled trial comparing preoxygenation with noninvasive ventilation and high-flow nasal oxygen before intubation of patients with acute hypoxemic respiratory failure (PaO/FiO < 300 mm Hg). Read More

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Seizure-mediated iron accumulation and dysregulated iron metabolism after status epilepticus and in temporal lobe epilepsy.

Acta Neuropathol 2021 Jul 22. Epub 2021 Jul 22.

Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.

Neuronal dysfunction due to iron accumulation in conjunction with reactive oxygen species (ROS) could represent an important, yet underappreciated, component of the epileptogenic process. However, to date, alterations in iron metabolism in the epileptogenic brain have not been addressed in detail. Iron-related neuropathology and antioxidant metabolic processes were investigated in resected brain tissue from patients with temporal lobe epilepsy and hippocampal sclerosis (TLE-HS), post-mortem brain tissue from patients who died after status epilepticus (SE) as well as brain tissue from the electrically induced SE rat model of TLE. Read More

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Intraoperative virtual reality distraction in TKA under spinal anesthesia: a preliminary study.

Arch Orthop Trauma Surg 2021 Jul 22. Epub 2021 Jul 22.

Institute for Locomotion, Department of Orthopedic Surgery, Aix-Marseille University, Sainte-Marguerite Hospital, 270, boulevard Sainte-Marguerite, 13009, Marseille, France.

Introduction: The effect of patient anxiety during the perioperative period has been shown to be of great importance in its influence on post-operative recovery. Over the last 10 years, virtual reality (VR) has been developed in anesthesia for patient's distraction by immersion. The aim of this study was to evaluate post-operative patient anxiety the day after TKA surgery under spinal anesthesia (SA) with or without VR distraction. Read More

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Bone mineral density and oxidative stress in adolescent girls with anorexia nervosa.

Eur J Pediatr 2021 Jul 22. Epub 2021 Jul 22.

Department of Pediatrics, Faculty of Medicine, National Institute of Children's Diseases, Comenius University, Limbová 1, 833 40, Bratislava, Slovakia.

Oxidative stress appears to be involved in the pathogenesis of osteoporosis-a serious complication of anorexia nervosa (AN). We evaluated the oxidative status in adolescent girls with AN and its potential relationship with bone mineral density (BMD). Girls with AN (n = 43) and age-matched healthy controls (n = 20) underwent anthropometric and BMD examination. Read More

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Venetoclax enhances T cell-mediated antileukemic activity by increasing ROS production.

Blood 2021 Jul;138(3):234-245

Princess Margaret Cancer Centre, University Health Network, Toronto, ON, Canada.

Venetoclax, a Bcl-2 inhibitor, in combination with the hypomethylating agent azacytidine, achieves complete remission with or without count recovery in ∼70% of treatment-naive elderly patients unfit for conventional intensive chemotherapy. However, the mechanism of action of this drug combination is not fully understood. We discovered that venetoclax directly activated T cells to increase their cytotoxicity against acute myeloid leukemia (AML) in vitro and in vivo. Read More

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Effects of Exercise Structure and Modality on Physiological and Perceptual Responses to Exercise.

J Strength Cond Res 2021 Jul 20. Epub 2021 Jul 20.

School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece; and Department of Kinesiology, California State University-San Marcos, San Marcos, California.

Abstract: Bogdanis, GC, Mallios, VJ, Katsikas, C, Fouseki, T, Holman, I, Smith, C, and Astorino, TA. Effects of exercise structure and modality on physiological and perceptual responses to exercise. J Strength Cond Res XX(X): 000-000, 2021-This study examined the effect of exercise mode and intensity on physiological and perceptual responses to exercise. Read More

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