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LitCovid-PD-HP

{"project":"LitCovid-PD-HP","denotations":[{"id":"T3","span":{"begin":785,"end":804},"obj":"Phenotype"},{"id":"T4","span":{"begin":911,"end":920},"obj":"Phenotype"},{"id":"T5","span":{"begin":926,"end":935},"obj":"Phenotype"},{"id":"T6","span":{"begin":943,"end":963},"obj":"Phenotype"}],"attributes":[{"id":"A3","pred":"hp_id","subj":"T3","obj":"http://purl.obolibrary.org/obo/HP_0002086"},{"id":"A4","pred":"hp_id","subj":"T4","obj":"http://purl.obolibrary.org/obo/HP_0002090"},{"id":"A5","pred":"hp_id","subj":"T5","obj":"http://purl.obolibrary.org/obo/HP_0012418"},{"id":"A6","pred":"hp_id","subj":"T6","obj":"http://purl.obolibrary.org/obo/HP_0002098"}],"text":"1. Introduction\nAfter a series of acute respiratory syndrome cases of unknown cause were reported in December 2019 in Wuhan, Hubei province, China, genome sequencing of lower respiratory tract samples from patients showed the presence of a novel human coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) [1,2] and the disease associated with SARS-CoV-2 was termed Corona Virus Disease 2019 (COVID-19). On 11 March 2020, the World Health Organization (WHO) declared the outbreak a global pandemic. Until now (November 2020), more than 47 million COVID-19 cases have been reported globally by the WHO.\nWhile most of SARS-CoV-2 infected subjects are pauci-symptomatic [3] and about 15% asymptomatic [4], in some individuals the disease can develop to a more serious respiratory illness requiring hospitalization and intensive care treatment when it progresses to a critical illness involving pneumonia with hypoxemia, acute respiratory distress syndrome and severe systemic inflammation [5]. The infection-fatality rate (IFR) is determined currently to be 0.68% (0.53–0.82%) [6], with a decrease in the number to be expected due to the current increased divergence between the infection and death rates globally. The IFR is a function of age, with an IFR of \u003c0.01% for subjects under 25 years of age and a log-linear increase of the IFR for subjects older than 30 years [7].\nAs critically ill patients are often found to form methemoglobin (MetHb) [8,9,10] and carboxyhemoglobin (COHb) [11,12], MetHb and COHb formation might also be relevant in case of COVID-19. MetHb is formed when the ferrous iron (Fe2+) of the heme group of hemoglobin (Hb) is oxidized to ferric iron (Fe3+). The ferric iron of MetHb is unable to bind oxygen (O2). Thus, the O2 dissociation curve is left-shifted, making it more difficult to release O2 and to provide proper tissue oxygenation. The formation of MetHb also results in less Hb available for O2 binding and transport.\nMetHb is continuously produced under physiological conditions in a limited amount due to auto-oxidation, but it is rapidly converted back to Hb primarily by nicotinamide adenine dinucleotide (NADH)-dependent cytochrome-b5 reductase (also known as MetHb reductase) and to a limited degree also by ascorbate and glutathione [13]. COHb is formed when Hb and carbon monoxide (CO) interact; CO binds to heme molecules 240 times more than O2. The resulting COHb limits the blood’s O2-carrying capacity [14]. In healthy, non-smoking individuals, MetHb is in the range of 0.67 ± 0.33% [15] and COHb in the range of 0.5–1.5% [16].\nThe aim of our study was to summarize the currently available published study results (case reports and cross sectional studies) on MetHb and COHb in patients with COVID-19."}

LitCovid-sentences

{"project":"LitCovid-sentences","denotations":[{"id":"T12","span":{"begin":0,"end":2},"obj":"Sentence"},{"id":"T13","span":{"begin":3,"end":15},"obj":"Sentence"},{"id":"T14","span":{"begin":16,"end":423},"obj":"Sentence"},{"id":"T15","span":{"begin":424,"end":518},"obj":"Sentence"},{"id":"T16","span":{"begin":519,"end":621},"obj":"Sentence"},{"id":"T17","span":{"begin":622,"end":1010},"obj":"Sentence"},{"id":"T18","span":{"begin":1011,"end":1231},"obj":"Sentence"},{"id":"T19","span":{"begin":1232,"end":1393},"obj":"Sentence"},{"id":"T20","span":{"begin":1394,"end":1582},"obj":"Sentence"},{"id":"T21","span":{"begin":1583,"end":1699},"obj":"Sentence"},{"id":"T22","span":{"begin":1700,"end":1755},"obj":"Sentence"},{"id":"T23","span":{"begin":1756,"end":1885},"obj":"Sentence"},{"id":"T24","span":{"begin":1886,"end":1972},"obj":"Sentence"},{"id":"T25","span":{"begin":1973,"end":2300},"obj":"Sentence"},{"id":"T26","span":{"begin":2301,"end":2409},"obj":"Sentence"},{"id":"T27","span":{"begin":2410,"end":2474},"obj":"Sentence"},{"id":"T28","span":{"begin":2475,"end":2594},"obj":"Sentence"},{"id":"T29","span":{"begin":2595,"end":2768},"obj":"Sentence"}],"namespaces":[{"prefix":"_base","uri":"http://pubannotation.org/ontology/tao.owl#"}],"text":"1. Introduction\nAfter a series of acute respiratory syndrome cases of unknown cause were reported in December 2019 in Wuhan, Hubei province, China, genome sequencing of lower respiratory tract samples from patients showed the presence of a novel human coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) [1,2] and the disease associated with SARS-CoV-2 was termed Corona Virus Disease 2019 (COVID-19). On 11 March 2020, the World Health Organization (WHO) declared the outbreak a global pandemic. Until now (November 2020), more than 47 million COVID-19 cases have been reported globally by the WHO.\nWhile most of SARS-CoV-2 infected subjects are pauci-symptomatic [3] and about 15% asymptomatic [4], in some individuals the disease can develop to a more serious respiratory illness requiring hospitalization and intensive care treatment when it progresses to a critical illness involving pneumonia with hypoxemia, acute respiratory distress syndrome and severe systemic inflammation [5]. The infection-fatality rate (IFR) is determined currently to be 0.68% (0.53–0.82%) [6], with a decrease in the number to be expected due to the current increased divergence between the infection and death rates globally. The IFR is a function of age, with an IFR of \u003c0.01% for subjects under 25 years of age and a log-linear increase of the IFR for subjects older than 30 years [7].\nAs critically ill patients are often found to form methemoglobin (MetHb) [8,9,10] and carboxyhemoglobin (COHb) [11,12], MetHb and COHb formation might also be relevant in case of COVID-19. MetHb is formed when the ferrous iron (Fe2+) of the heme group of hemoglobin (Hb) is oxidized to ferric iron (Fe3+). The ferric iron of MetHb is unable to bind oxygen (O2). Thus, the O2 dissociation curve is left-shifted, making it more difficult to release O2 and to provide proper tissue oxygenation. The formation of MetHb also results in less Hb available for O2 binding and transport.\nMetHb is continuously produced under physiological conditions in a limited amount due to auto-oxidation, but it is rapidly converted back to Hb primarily by nicotinamide adenine dinucleotide (NADH)-dependent cytochrome-b5 reductase (also known as MetHb reductase) and to a limited degree also by ascorbate and glutathione [13]. COHb is formed when Hb and carbon monoxide (CO) interact; CO binds to heme molecules 240 times more than O2. The resulting COHb limits the blood’s O2-carrying capacity [14]. In healthy, non-smoking individuals, MetHb is in the range of 0.67 ± 0.33% [15] and COHb in the range of 0.5–1.5% [16].\nThe aim of our study was to summarize the currently available published study results (case reports and cross sectional studies) on MetHb and COHb in patients with COVID-19."}

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LitCovid-sentences

PMC:7795966 / 1849-4617 JSON TXT