Epistemic_Statements  

CORD-19:e6fd10dbd99717ea319bed4c6dbc9d0a421e656c JSONTXT 8 Projects

Annnotations TAB TSV DIC JSON TextAE

Id Subject Object Predicate Lexical cue
T1 620-725 Epistemic_statement denotes Genotype III consisted of eight Chinese isolates that showed close relationship with Korean IBV isolates.
T2 909-1023 Epistemic_statement denotes Two isolates, HN99 and CK/CH/LHN/00I, which might be a reisolation of vaccine strains, clustered into genotype VI.
T3 2938-3401 Epistemic_statement denotes The S glycoprotein of IBV, located on the outside of all virions, is responsible for fusion (virus envelope to cell membrane and cell membrane to cell membrane) and is translated as a precursor protein (S 0 ), then cleaved into a carboxy-terminal S2 subunit (approximately 625 amino acid residues), which anchors S in the virus envelope, and an amino-terminal S1 subunit (approximately 520 residues), believed to largely form the distal bulbous part of S [3, 7] .
T4 3710-3912 Epistemic_statement denotes Serotypic evolution in IBV is associated primarily with the sequences of the S1 glycoprotein, and the genetic diversity of IBV is mainly monitored by analysis of the S1 gene [2, 9, 10, 23, 27, 32, 42] .
T5 4209-4338 Epistemic_statement denotes However, the epidemiological analysis of IBV isolates in China has not been thorough except for with a few strains [31, 28, 46] .
T6 4339-4482 Epistemic_statement denotes The relationships between Chinese IBV isolates and foreign IBV isolates, especially Korean, Taiwanese and Japanese IBV isolates, are not known.
T7 4640-4833 Epistemic_statement denotes This will determine the IBV type(s) which are necessary for understanding the epidemiology and evolution of IBVs, as well as isolation of the virus, which is important for improved vaccination.
T8 6885-7015 Epistemic_statement denotes Owing to genetic variations among IBV isolates, it is difficult to design PCR primers that can be used to detect all IBV isolates.
T9 10154-10428 Epistemic_statement denotes IBV strains from the above 3 geographically different areas were selected because we were interested in knowing whether the IBV isolates in China were introduced from neighboring countries and continents or whether they arose by mutations of circulating Chinese IBV strains.
T10 12414-12561 Epistemic_statement denotes The Korean IBV isolate, K069-01, which belonged to genotype III of Korean IBV strains [27] , was closely related to those isolates in genotype III.
T11 15054-15436 Epistemic_statement denotes Chinese IBV isolates HN99 and CK/CH/LHN/00I, which were grouped in genotype VI, had a cleavage recognition site, Arg-Arg-Ser-Arg-Arg, which was the most common site reported by Jackwood [22] , who had compared the cleavage recognition sites of fifty-five IBV isolates to determine if the site sequence correlates with host cell range, serotype, geographic origin, and pathogenicity.
T12 16139-16313 Epistemic_statement denotes The S1 protein genes, which varied from 0.2 to 26.7% among the strains examined, indicated that point mutations, deletions, and insertions contribute to the evolution of IBV.
T13 18082-18303 Epistemic_statement denotes The deletions and insertions, which occurred in the predicted amino acid sequences of the S1 proteins of fifty-seven IBV strains in this study, were correlated with the genotypes of S1 protein genes, as shown in Table 4 .
T14 19639-19920 Epistemic_statement denotes Although the genetic basis of IBV pathogenicity is not known, the S1 protein gene of IBV has serotype-specific and neutralization-specific epitopes, and serotypic evolution and the genetic diversity of IBV is mainly monitored by analysis of the S1 gene [2, 9, 10, 23, 27, 32, 42] .
T15 20055-20321 Epistemic_statement denotes IBVs isolated ten years ago were included in the same genotype with the strains isolated recently (for example, CK/CH/LSC/95I and CK/CH/ LGD/03I in genotype III), indicating that this genotype may be indigenous and has been prevalent in China for at least ten years.
T16 20322-20599 Epistemic_statement denotes Serotype differences among the genetically distinct IBVs generally correlated with variations in the HVR of the S1 protein gene [4, 8] and differences of as little as 5% between S1 sequences of IBV could result in poor cross-protection offered by currently used vaccines [19] .
T17 20600-20923 Epistemic_statement denotes The low identities (<83%) of amino acid sequences between Chinese IBV isolates and H120, except for those of the Mass-type IBV, which were included in genotype V in this study, may account for the prevalence of the viruses during the past ten years in spite of the extensive use of Mass-type vaccines in the field in China.
T18 21009-21402 Epistemic_statement denotes Although the number of basic residues around the spike glycoprotein cleavage recognition site of IBV does not appear to correlate with increased cleavability, host cell range, and increased virulence as it does with the envelope glycoproteins of orthomyxoviruses and paramyxoviruses, the sequences of cleavage recognition sites was correlated with geographic distribution of the viruses [22] .
T19 21667-21960 Epistemic_statement denotes However, a Korean IBV strain, K069-01, shared the same cleavage recognition site sequence, Arg-Arg-Phe-Arg-Arg, with ten Chinese isolates included in subgenotypes III (six strains) and IV (four strains), ten Chinese Mass-type isolates (genotype V), and two Taiwan isolates, 3015/02 and T07/02.
T20 22656-22891 Epistemic_statement denotes Unlike K069-01, isolates 3051/02 and T07/02, which represented TW I and TW II strains, respectively [20] , were clustered into a separate branch that was separated from the Chinese genotypes, indicating that they had different origins.
T21 23211-23346 Epistemic_statement denotes However, Chinese Mass-type strains were all isolated in the 1990s and were not the major IBV type circulating in recent years in China.
T22 23347-23588 Epistemic_statement denotes Molecular studies have shown that a new serotype or variant can emerge as a result of only a few changes in the amino acid composition in the S1 part of the virus spike protein, with the majority of the virus genome remaining unchanged [6] .
T23 23589-23836 Epistemic_statement denotes This could be due to immunologic pressure caused by the widespread use of vaccines, to recombination as a consequence of mixed infections, or to the decrease of dominant serotypes as a result of vaccination, allowing other field strains to emerge.
T24 23837-24031 Epistemic_statement denotes To this study, the Mass-type viruses may have come from the vaccine strains by point mutation, although the possibility that some of them were reisolations of vaccine strains cannot be excluded.
T25 24362-24568 Epistemic_statement denotes Interestingly, BLAST searches revealed significant similarity (99%) of S1 protein genes between isolate HN99 and a vaccine strain, JAAS (AY839140), which was from Australia and used in China to control IBV.
T26 24862-25045 Epistemic_statement denotes The spreading of a virus from one area or country to another could be due, at least in part, to its improper introduction by the trading of birds or by the use of attenuated vaccines.
T27 25046-25367 Epistemic_statement denotes To our knowledge, no other IBV strains related to HN99 or CK/CH/LHN00I were isolated in recent years in China, and considering the pathogenicity and genetically close relationship between the two isolates and the corresponding vaccine strains, we speculated that the two isolates would be reisolations of vaccine strains.
T28 26067-26352 Epistemic_statement denotes The diversity of the pathogenicity of IBV strains was expected; although the primary tissue of IBV infection is the respiratory tract, some isolates can grow in nonrespiratory organs such as the kidney, the female reproductive tract, intestine, and spleen of chickens [2, 14, 33, 36] .
T29 26353-26569 Epistemic_statement denotes With the exception of the Massachusetts strain, a very interesting aspect of IBV epidemiology, as far as it is possible to know, is the presence and the spreading of the various IBV serotypes in different continents.
T30 26795-27003 Epistemic_statement denotes Besides genotypes I to IV and VII, the Mass-type IBV and IBV closely related to Australian classical strains were also present, indicating IBVs showing various genetic differences were cocirculating in China.