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Koning Nick Julius NJ VU University Medical Center - - 2014
Introduction: Previously we showed that cardiopulmonary bypass during cardiac surgery is associated with reduced sublingual microcirculatory perfusion and oxygenation. It has been suggested that impaired microcirculatory perfusion may be paralleled by increased heterogeneity of flow in the microvascular bed, possibly leading to arteriovenous shunting. Here we investigated our hypothesis that ...
Gould Ian G IG Department of Bioengineering, University of Illinois at Chicago, Chicago, - - 2014
Oxygen tension in the brain is controlled by the microcirculatory supply of red blood cells, but the effect of non-Newtonian blood flow rheology on tissue oxygenation is not well characterized. This paper assesses different biphasic blood flow models for predicting tissue oxygen tension as a function of microcirulatory hemodynamics. Two ...
Zhou Wei W Department of Neurology, University Heidelberg, INF 400, 69120, Heidelberg, Germany, - - 2014
Perihematomal edema exacerbates the mass effect of hematoma and contributes to early neurological deterioration after intracerebral hemorrhage (ICH). Oxygen therapy has protective effects on the blood-brain barrier (BBB). We aimed to examine the effects of oxygen therapy on edema formation and BBB permeability after ICH. ICH was induced in mice ...
Fiedler T T School of Engineering, The University of Newcastle, Callaghan, NSW 2287, Australia, - - 2014
Tissue engineering scaffolds are designed to support tissue self-healing within physiological environments by promoting the attachment, growth and differentiation of relevant cells. Newly formed tissue must be supplied with sufficient levels of oxygen to prevent necrosis. Oxygen diffusion is the major transport mechanism before vascularization is completed and oxygen is ...
Palkovits Stefan S Department of clinical Pharmacology, Medical University of Vienna, Vienna, 1090, - - 2014
Purpose: To characterize retinal metabolism during normoxia and hyperoxia in healthy subjects. Methods:Forty-six healthy subjects were included in the present study and data of 41 subjects could be evaluated. Retinal vessel diameters as well as oxygen saturation in arteries and veins were measured using the Dynamic Vessel Analyzer (DVA). In ...
Iida Hidehiro H Department of Investigative Radiology, National Cerebral and Cardiovascular Center Research Institute, Suita City, Osaka, - - 2014
We aimed at evaluating the adequacy of the commonly employed compartmental model for quantitation of cerebral metabolic rate of oxygen (CMRO2) using (15)O-labeled oxygen ((15)O2) and positron emission tomography (PET). Sequential PET imaging was carried out on monkeys following slow bolus injection of blood samples containing (15)O2-oxyhemoglobin ((15)O2-Hb), (15)O-labeled water ...
Hillman Elizabeth M C EM Departments of Biomedical Engineering and Radiology and the Kavli Institute for Brain Science, Columbia University, New York, NY 10027; email: - - 2014
Functional magnetic resonance imaging (fMRI) provides a unique view of the working human mind. The blood-oxygen-level-dependent (BOLD) signal, detected in fMRI, reflects changes in deoxyhemoglobin driven by localized changes in brain blood flow and blood oxygenation, which are coupled to underlying neuronal activity by a process termed neurovascular coupling. Over ...
Azocar Jose J Jose Azocar, MD, DSc, is Medical Director, Northgate Medical Center, Springfield, - - 2014
To develop a novel technique for increasing skin oxygenation based on diffusion principles and Fick's laws of diffusion. A device that allows the creation of an oxygen-depleted environment immediately to the skin while simultaneously allowing measurement of the transcutaneous oxygen tension (TcPo2) levels was created. This device forms an oxygen ...
Bäumler Hans H Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, - - 2014
During the last 30 years, artificial oxygen carriers have been investigated intensively with the aim to develop universal blood substitutes. Favorably, hemoglobin-based oxygen carriers (HBOCs) are expected to meet the sophisticated requirements. However, the HBOCs tested until now show serious side effects, which resulted in failure of clinical trials and ...
Mouridsen Kim K Center of Functionally Integrative Neuroscience and MINDLab, Institute of Clinical Medicine, Aarhus University, Aarhus, - - 2014
The regional availability of oxygen in brain tissue is traditionally inferred from the magnitude of cerebral blood flow (CBF) and the concentration of oxygen in arterial blood. Measurements of CBF are therefore widely used in the localization of neuronal response to stimulation and in the evaluation of patients suspected of ...
Liong Celine C Department of Bioengineering University of California, San Diego La Jolla, CA 92093 - - 2014
Hypoxia is the major hindrance to successful radiation therapy of tumors. Attempts to increase the oxygen (O2) tension (PO2) of tissue by delivering more O2 have been clinically disappointing, largely due to the way O2 is transported and released by the hemoglobin (Hb) within the red blood cells (RBCs). Systemic ...
Tao Zhimin Z David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, - - 2014
Here, we discuss recent advances in the development of artificial red blood cell (RBC) substitutes, illustrating lessons learned from initial attempts using perfluorocarbon (PFC) emulsions and acellular hemoglobin-based oxygen carriers (HBOCs). We also highlight novel oxygen-containing microparticles, nanoparticles, and stem cell-derived RBC products, with emphasis on improvements in biocompatibility and ...
Bell Graham T GT Department of Anaesthetics, Royal Hospital for Sick Children, Glasgow, - - 2014
To determine the limits of performance of the Farman Entrainer used with the t-piece for pediatric anesthesia in areas with limited oxygen supplies. Bench tests were conducted with different system configurations, normal and 'emergency situation' ventilation patterns were replicated to reproduce a range of circumstances the anesthetist may encounter. We ...
Schlager Oliver O Department of Medicine II, Division of Angiology, Medical University of Vienna, Vienna, - - 2014
Whether transfusions of packed red blood cells (PRBCs) affect tissue oxygenation in stable critically ill patients is still matter of discussion. The microvascular capacity for tissue oxygenation can be determined noninvasively by measuring transcutaneous oxygen tension (tcpO2). The aim of this study was to assess tissue oxygenation by measuring tcpO2 ...
Kocaoglu Baris B Department of Orthopaedics and traumatology, Acibadem University Faculty of Medicine, Acibadem Kadikoy Hospital, Tekin Sok. No: 8, 34718, Acibadem, Istanbul, Turkey, - - 2014
The aim of this study is to show whether peripheral perfusion monitoring methods reflect central perfusion during shoulder arthroscopy at beach chair position. We hypothesized that mean arterial pressure (MAP), central heart rate (CHR) and peripheral oxygenation (SaO2) measurements individually will not parallel cerebral oximetry measurements by near-infrared spectroscopy (NIRS). ...
Yousef Khalil M KM University of Jordan, Faculty of Nursing, Queen Rania Al Abdullah Street, Amman 11942, Jordan. Electronic address: - - 2014
To examine the relationship between regional cerebral oxygen saturation (rSO2), delayed cerebral ischaemia (DCI), and outcomes after aneurysmal subarachnoid haemorrhage (aSAH). Subjects (n=163) with aSAH, age 21-75 years, and Fisher grade >1 were included in the study. Continuous rSO2 monitoring was performed for 5-10 days after injury using near-infrared spectroscopy ...
Ariturk Cem C Department of Cardiovascular Surgery, University of Ac─▒badem Faculty of Medicine, Maltepe, Istanbul, - - 2014
Background: Our study evaluated changes in cerebral arterial oxygen saturation (rSO2) during cardiopulmonary bypass (CPB) that were caused by changes in arterial carbon dioxide tension (PaCO2).Methods: A group of 126 patients undergoing routine, elective, first-time coronary artery bypass graft surgery (CABG) was entered into a prospective study using bilateral near-infrared ...
Fahlman Asa - - 2014
For treatment of hypoxemia, delivery of the minimum effective oxygen flow rate is advantageous during field anesthesia because it prolongs the life of the oxygen cylinder. Portable oxygen concentrators as the oxygen source require less logistical considerations than cylinders and are a safer alternative during helicopter field work because they ...
Gilmore Kerry K Department for Biomolecular Systems, Max-Planck Institute for Colloids and Interfaces, Am Mühlenberg 1, 14476, Potsdam, - - 2014
Due to the narrow width of tubing/reactors used, photochemistry performed in micro- and mesoflow systems is significantly more efficient than when performed in batch due to the Beer-Lambert Law. Owing to the constant removal of product and facility of flow chemical scalability, the degree of degradation observed is generally decreased ...
Thio Marta M Neonatal Services, The Royal Women's Hospital, Melbourne, Australia; Hospital Sant Joan de Deu, Barcelona, Spain; The University of Melbourne, Victoria, Australia. Electronic address: - - 2014
To test whether 4 commonly used self-inflating bags with a reservoir in situ can reliably deliver different oxygen concentrations (21%-100%) using a portable oxygen cylinder with flows of ≤5 L/min. Four self-inflating bags (from Laerdal, Ambu, Parker Healthcare, and Mayo Healthcare) were tested to provide positive pressure ventilation to a manikin ...
Schmitz J J Department of Paediatrics, Division of Neonatology, Medical University of Graz, Graz, - - 2014
The aim of this study was to analyse the feasibility of long-term measurements of cerebral (crSO2) and peripheral (prSO2) regional tissue oxygen saturation on the first day of life by determining the amount of artefacts and their influence on rSO2. Near infrared spectroscopy (NIRS) measurements were performed fronto-parietal left (crSO2) ...
Song Youngkyu Y Division of Magnetic Resonance, Korea Basic Science Institute, Cheongwon, Chungbuk, South - - 2014
In comparison to the well-documented significance of intravascular deoxyhemoglobin (deoxyHgb), the effects of dissolved oxygen on the blood-oxygen-level-dependent (BOLD) signal have not been widely reported. Based on the fact that the prolonged inspiration of high oxygen fraction gas can result in up to a sixfold increase of the baseline tissue ...
Hirsch Nuria M NM Department of Neuroradiology, Technische Universität München, Munich, - - 2014
A blood oxygenation level-dependent (BOLD)-based apparent relative oxygen extraction fraction (rOEF) as a semi-quantitative marker of vascular deoxygenation has recently been introduced in clinical studies of patients with glioma and stroke, yielding promising results. These rOEF measurements are based on independent quantification of the transverse relaxation times T2 and T2 ...
Fahlman Asa A 1  Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, SE-750 07 Uppsala, - - 2014
Abstract Hypoxemia is anticipated during wildlife anesthesia and thus should be prevented. We evaluated the efficacy of low flow rates of supplemental oxygen for improvement of arterial oxygenation in anesthetized brown bears (Ursus arctos). The study included 32 free-ranging brown bears (yearlings, subadults, and adults; body mass 12-250 kg) that were ...
Zhou Steven S Respiratory Institute, Cleveland Clinic, Cleveland, - - 2014
The FIO2 for a nasal cannula with constant flow (CF) depends on the anatomic reservoir (AR), which is affected by changes in frequency and end-expiratory flow. Conversely, pulse flow (PF) devices do not require the AR. The purpose of this study was to compare the FIO2 delivered by a nasal ...
Martini M M Klinik und Poliklinik für Mund-, Kiefer- und Plastische Gesichtschirurgie, Universitätsklinik Bonn, Bonn, - - 2014
Focal pressure-related changes in brain perfusion and metabolism are discussed in single-suture craniosynostosis and brachycephalic cases (bicoronal synostosis). Raised intracranial pressure levels could be measured in some cases. In order to find possible loco-regional brain tissue changes during plastic surgery, we investigated oxygenation and perfusion parameters using non-invasive near-infrared spectroscopy ...
Strömberg Tomas T Linköping University, University Hospital, Department of Biomedical Engineering, Linköping 581 85, - - 2014
ABSTRACT. Microvascular assessment would benefit from co-registration of blood flow and hemoglobin oxygenation dynamics during stimulus response tests. We used a fiber-optic probe for simultaneous recording of white light diffuse reflectance (DRS; 475-850 nm) and laser Doppler flowmetry (LDF; 780 nm) spectra at two source-detector distances (0.4 and 1.2 mm). An inverse Monte ...
Liu Peiying P Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA; Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, - - 2014
Long-term cocaine use is known to negatively impact neural and cerebrovascular systems. However, the use of imaging markers to separately assess these parameters remains challenging. The primary reason is that most functional imaging markers, such as cerebral blood flow, functional connectivity, and task-evoked functional MRI, are known to reflect a ...
van Veen Theun T Clinical Engineering, Institute of Ageing and Chronic Disease, University of Liverpool, - - 2014
The use of red blood cells (RBCs) in transfusion is widespread in modern medicine. Limitations in blood transfusion have made an urgent argument for the focus on alternatives, as particular medical treatments heavily rely on the supply of donated blood. Stem cells have been successfully used in vitro to produce ...
Hirasawa Ai A Graduate school of Engineering, Toyo University, Kawagoe-shi, Saitama, - - 2014
Most near-infrared spectroscopy (NIRS) apparatus fails to isolate cerebral oxygenation from an extracranial contribution although they use different source-detector distances. Nevertheless, the effect of different source-detector distances and change in extracranial blood flow on the NIRS signal has not been identified in humans. This study evaluated the extracranial contribution, as ...
Palmer Andre F AF William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio 43210; email: - - 2014
The toxic side effects of early generations of red blood cell substitutes have stimulated development of more safe and efficacious high-molecular-weight polymerized hemoglobins, poly(ethylene glycol)-conjugated hemoglobins, and vesicle-encapsulated hemoglobins. Unfortunately, the high colloid osmotic pressure and blood plasma viscosity of these new-generation materials limit their application to blood concentrations that, ...
Petersen Anja S AS Danish Headache Center, Department of Neurology, Glostrup Hospital, University of Copenhagen, - - 2014
Our aim was to review the existing literature to document oxygen's therapeutic effect on cluster headache. A PubMed search resulted in 28 hits, and from these and their references we found in total 11 relevant studies. We included six studies that investigated the efficacy of oxygen treatment. One study is ...
Voicu Sebastian S 1Medical and Toxicological Intensive Care Department, Lariboisière University Hospital, APHP, Paris, France. 2INSERM U942, Université Paris Diderot, Paris, France. 3Cardiology Department, Lariboisière University Hospital, APHP, Paris, France. 4Department of Anesthesiology and Critical Care, CHU Bicêtre, APHP, Le Kremlin-Bicêtre, France. 5INSERM U705, Université Paris Denis Diderot, Paris, France. 6Department of Anaesthesia and Intensive care, Lariboisière University Hospital, APHP, Paris, France. 7SAMU 75 and Department of Anesthesiology, Necker Hospital, APHP, Paris Descartes University, Medical School, Paris, France. 8Biochemical Laboratory, Lariboisière University Hospital, APHP, Paris, - - 2014
In patients treated with therapeutic hypothermia after out-of-hospital cardiac arrest, two blood gas management strategies are used regarding the PaCO2 target: α-stat or pH-stat. We aimed to compare the effects of these strategies on cerebral blood flow and oxygenation. Prospective observational single-center crossover study. ICU of University hospital. Twenty-one therapeutic ...
De Georgia Michael A MA Case Western Reserve University School of Medicine, Neurological Institute, University Hospitals Case Medical Center, Cleveland, OH, - - 2014
Brain injury results from ischemia, tissue hypoxia, and a cascade of secondary events. The cornerstone of neurocritical care management is optimization and maintenance of cerebral blood flow (CBF) and oxygen and substrate delivery to prevent or attenuate this secondary damage. New techniques for monitoring brain tissue oxygen tension (PtiO2) are ...
Kuliga Katarzyna Z KZ Human Development & Health, Faculty of Medicine, University of Southampton, - - 2014
We have evaluated the dynamics of skin microvascular blood flow (BF) and tissue oxygenation parameters (OXY) measured simultaneously at the same site using a combined non-invasive BF+OXY+temperature probe. Skin BF, oxygenated (oxyHb) and deoxygenated (deoxyHb) haemoglobin and mean oxygen saturation (SO2 ) were measured in 50 healthy volunteers at rest ...
Neelavalli Jaladhar - - 2014
To evaluate fetal cerebral venous blood oxygenation, Yv, using principles of MR susceptometry. A cohort of 19 pregnant subjects, with a mean gestational age of 31.6 ± 4.7 weeks were imaged using a modified susceptibility-weighted imaging (SWI) sequence. Data quality was first assessed for feasibility of oxygen saturation measurement, and ...
De Vis J B JB Department of Radiology, University Medical Centre Utrecht, HP E 01.132, P.O. Box 85500, 3508GA, Utrecht, The Netherlands. Electronic address: - - 2014
Brain oxygen consumption reflects neuronal activity and can therefore be used to investigate brain development or neuronal injury in neonates. In this paper we present the first results of a non-invasive MRI method to evaluate whole brain oxygen consumption in neonates. For this study 51 neonates were included. The T1 ...
Weenink R P RP Diving Medical Center, Royal Netherlands Navy, PO Box 1000, 1780 CA, Den Helder, The Netherlands; Laboratory of Experimental Intensive Care and Anaesthesiology (L.E.I.C.A.), Department of Anaesthesiology, Academic Medical Center, University of Amsterdam, PO Box 22660, 1100 DD, Amsterdam, The Netherlands. Electronic address: - - 2014
Cerebral air emboli occur as a complication of invasive medical procedures. The sensitivity of cerebral monitoring methods for the detection of air emboli are not known. This study investigates the utility of electroencephalography and non-invasively measured cerebral oxygen saturation in the detection of intracerebrovascular air. In 12 pigs oxygen saturation ...
Tarumi Takashi T Institute for Exercise and Environmental Medicine, Texas Health Presbyterian Hospital Dallas, Dallas, TX, USA Department of Internal Medicine, Alzheimer's Disease Center, University of Texas Southwestern Medical Center, Dallas, TX, - - 2014
Background: Vascular disease and dysfunction are associated with the higher risk of Alzheimer's disease hypothetically due to cerebral hypoperfusion. Brain perfusion is protected by cerebral autoregulation, which, under normal conditions, maintains a constant cerebral blood flow and brain tissue oxygenation. Objective: To determine whether dynamic regulation of cerebral blood flow ...
Belohlavek J J 2Department of Internal Medicine, Cardiovascular Medicine, General University Hospital in Prague, Prague, Czech - - 2014
The adequacy of cerebral blood flow and the level of regional oxygen saturation during CPR and early post-resuscitation phases assuring favorable neurological outcome are not known. We demonstrate the feasibility of cerebral blood flow and oxygenation monitoring by a continuous transcranial Doppler combined with cerebral oximetry in a patient with ...
Shimizu Madoka M Department of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8573, - - 2014
Here, we report an interaction between blood and redox nanoparticles, prepared by self-assembly of amphiphilic block copolymers possessing 2,2,6,6-tetramethylpiperidine-N-oxyls as a side chain of hydrophobic segment. When 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl was added to rat whole blood, its electron spin resonance signal disappeared rapidly. In contrast, the signal from redox nanoparticles remained for ...
Gramer M M Max-Planck-Institute of Neurological Research, Gleueler Str. 50, 50825 Cologne, Germany. Electronic address: - - 2014
Brain function critically relies on the supply with energy substrates (oxygen and glucose) via blood flow. Alterations in energy demand as during neuronal activation induce dynamic changes in substrate fluxes and blood flow. To study the complex system that regulates cerebral metabolism requires the combination of methods for the simultaneous ...
Andrewartha Sarah Jane SJ - - 2014
Marsupial joeys are born ectothermic and develop endothermy within their mother's thermally stable pouch. We hypothesised that tammar wallaby joeys would switch from α-stat to pH-stat regulation during the transition from ectothermy to endothermy. To address this, we compared ventilation (VE), metabolic rate (VO2) and variables relevant to blood gas ...
Sørensen Henrik H Department of Anaesthesia, The Copenhagen Muscle Research Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark; Zürich Centre for Integrative Human Physiology, University of Zürich, Zürich, - - 2014
Frontal lobe oxygenation (Sc O2 ) is assessed by spatially resolved near-infrared spectroscopy (SR-NIRS) although it seems influenced by extra-cerebral oxygenation. We aimed to quantify the impact of extra-cerebral oxygenation on two SR-NIRS derived Sc O2 . Multiple regression analysis estimated the influence of extra-cerebral oxygenation as exemplified by skin ...
Dunaev A V AV Photonics and Nanoscience Group, Division of Physics, School of Engineering, Physics and Mathematics, University of Dundee, Dundee DD1 4HN, UK. State University-Education-Science-Production Complex, Scientific-Educational Center of 'Biomedical Engineering', Oryol 302020, - - 2014
Multi-functional laser non-invasive diagnostic systems allow the study of a number of microcirculatory parameters, including index of blood microcirculation (Im) (by laser Doppler flowmetry, LDF) and oxygen saturation (StO2) of skin tissue (by tissue reflectance oximetry, TRO). This research aimed to use such a system to investigate the synchronization of ...
Sedlacik Jan J Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. Electronic address: - - 2014
The non-invasive assessment of (patho-)physiological parameters such as, perfusion and oxygenation, is of great importance for the characterization of pathologies e.g., tumors, which may be helpful to better predict treatment response and potential outcome. To better understand the influence of physiological parameters on the investigated oxygenation and perfusion sensitive MRI ...
Dawson J A JA Newborn Research Centre, The Royal Women's Hospital, , Melbourne, Victoria, - - 2014
Administration of oxygen in the delivery room is informed by oxygen saturation (SpO2). An oxygen saturation range of 60%-70% is the threshold for administering oxygen in the first minutes after birth. The accuracy of newer generation oximeters to measure SpO2 has not been compared against the 'gold standard', direct arterial ...
Nunes Liane Brescovici LB Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, Emergency Department, Intensive Care Unit, São PauloSP, Brazil, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Emergency Department, Intensive Care Unit, São Paulo/SP, - - 2014
Veno-venous extracorporeal oxygenation for respiratory support has emerged as a rescue alternative for patients with hypoxemia. However, in some patients with more severe lung injury, extracorporeal support fails to restore arterial oxygenation. Based on four clinical vignettes, the aims of this article were to describe the pathophysiology of this concerning ...
Hawkins Justin L - - 2014
Failure of components integrated into the cardiopulmonary bypass circuit, although rare, can bring about catastrophic results. One of these components is the heat exchanger of the membrane oxygenator. In this compartment, unsterile water from the heater cooler device is separated from the sterile blood by stainless steel, aluminum, or by ...
Kolettas Alexander A 1 Anaesthesiology Department, "Saint Luke" Private Clinic, Thessaloniki, Panorama, Greece ; 2 Anaesthesiology Department, 3 Cardiology Department, "AHEPA" University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece ; 4 Pulmonary Department, "G. Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece ; 5 Cardiothoracic Surgery Department, "Saint Luke" Private Clinic, Thessaloniki, Panorama, Greece ; 6 Surgery Department (NHS), University General Hospital of Alexandroupolis, Democritus University of Thrace, Alexandroupolis, Greece ; 7 Internal Medicine Department, "Theageneio" Cancer Hospital, Thessaloniki, Greece ; 8 Internal Medicine Department, Regional Hospital of Samos, Samos, Greece ; 9 Onocology Department, 10 Cardiology Department, "Saint Luke" Private Clinic, Thessaloniki, Panorama, - - 2014
Apnoeic oxygenation is an alternative technique of oxygenation which is recommended in the consecutive oxygen administration with varying flows (2-10 lt/min) through a catheter which is positioned over the keel of the trachea. Apnoeic oxygenation maintains for a significant period of time the oxygenation of blood in breathless conditions. This ...
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