Genome editing technologies have revolutionized the field of plant science by enabling targeted modification of plant genomes and are emerging as powerful tools for both plant gene functional analyses and crop improve...Genome editing technologies have revolutionized the field of plant science by enabling targeted modification of plant genomes and are emerging as powerful tools for both plant gene functional analyses and crop improvement. Although homology-directed repair(HDR)is a feasible approach to achieve precise gene replacement and base substitution in some plant species, the dominance of the non-homologous end joining pathway and low efficiency of HDR in plant cells have limited its application. Base editing has emerged as an alternative tool to HDR-mediated replacement, facilitating precise editing of plant genome by converting one single base to another in a programmable manner without a doublestranded break and a donor repair template. In this review, we summarize the latest developments in base-editing technologies as well as their underlying mechanisms. We review current applications of these technologies in plant species. Finally, we address the challenges and future perspectives of this emerging technology in plants.展开更多
BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution th...BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis techniques.In a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital stay.AIM To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor outcomes.METHODS This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography scan.Laboratory and clinical data were obtained from electronic records.Categorical variables were compared using Fisher’s exact test.Continuous data were presented as median and interquartile range.The Mann-Whitney U test was used for comparisons.RESULTS In total,211 patients were analyzed.The mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus hydrogenii.Of those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory origin.The non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score 3.We did not find severe acid-base imbalance in this population.The analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not different between the groups.CONCLUSION A展开更多
基金partly funded by the Transgenesis Initiative Project supported by the Ministry of Agriculture and Rural Affairs of China(2019ZX08010001,2019ZX08010003)the Central Non-Profit Fundamental Research Funding supported by the Institute of Crop Sciences,Chinese Academy of Agricultural Sciences(S2018QY05)。
文摘Genome editing technologies have revolutionized the field of plant science by enabling targeted modification of plant genomes and are emerging as powerful tools for both plant gene functional analyses and crop improvement. Although homology-directed repair(HDR)is a feasible approach to achieve precise gene replacement and base substitution in some plant species, the dominance of the non-homologous end joining pathway and low efficiency of HDR in plant cells have limited its application. Base editing has emerged as an alternative tool to HDR-mediated replacement, facilitating precise editing of plant genome by converting one single base to another in a programmable manner without a doublestranded break and a donor repair template. In this review, we summarize the latest developments in base-editing technologies as well as their underlying mechanisms. We review current applications of these technologies in plant species. Finally, we address the challenges and future perspectives of this emerging technology in plants.
文摘BACKGROUND Acid-base imbalance has been poorly described in patients with coronavirus disease 2019(COVID-19).Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been over-looked using traditional acid-base analysis techniques.In a cohort of critically ill COVID-19 patients,we looked for an association between metabolic acidosis surrogates and worse clinical outcomes,such as mortality,renal dialysis,and length of hospital stay.AIM To describe the acid-base disorders of critically ill COVID-19 patients using Stewart’s approach,associating its variables with poor outcomes.METHODS This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography scan.Laboratory and clinical data were obtained from electronic records.Categorical variables were compared using Fisher’s exact test.Continuous data were presented as median and interquartile range.The Mann-Whitney U test was used for comparisons.RESULTS In total,211 patients were analyzed.The mortality rate was 13.7%.Overall,149 patients(70.6%)presented with alkalosis,28 patients(13.3%)had acidosis,and the remaining 34 patients(16.2%)had a normal arterial pondus hydrogenii.Of those presenting with acidosis,most had a low apparent strong ion difference(SID)(20 patients,9.5%).Within the group with alkalosis,128 patients(61.0%)had respiratory origin.The non-survivors were older,had more comorbidities,and had higher Charlson’s and simplified acute physiology score 3.We did not find severe acid-base imbalance in this population.The analyzed Stewart’s variables(effective SID,apparent SID,and strong ion gap and the effect of albumin,lactate,phosphorus,and chloride)were not different between the groups.CONCLUSION A
