两种俯卧位角度对急性呼吸窘迫综合征机械通气患者临床指标的影响

目的比较10°和25°头高足低俯卧位通气角度对急性呼吸窘迫综合征(ARDS)患者氧合指标、血流动力学、压力性损伤发生率、VAP发生率的影响。方法将2020年4月—2021年4月医院收治的ARDS患者,按组间特征具有可比性的原则分为观察组25例和对照组26例。对照组患者给予10°头高足低俯卧位,观察组患者给予25°头高足低俯卧位,观察比较两组俯卧位动脉血氧分压(PaO_(2))、二氧化碳分压(PaCO_(2))、氧合指数(PaO_(2)/FiO_(2))、血流动力学指标、压力性损伤发生率、VAP的发生情况。结果俯卧位后两组氧合指标、心率等较俯卧位前均有改善,但两指标组间比较差异无统计学意义(P>0.05)。观察组患者压力性损伤发生率及VAP发生率低于对照组,差异有统计学意义(P<0.05)。结论ARDS患者取25°头高足低俯卧位通气既可以有效改善氧合,也可以降低患者压力性损伤及VAP发生率,是ARDS患者行机械通气时较合适的体位。

A loss-of-function mutant allele of a glycosyl hydrolase gene has been co-opted for seed weight control during soybean domestication

The resultant DNA from loss-of-function mutation can be recruited in biological evolution and development.Here,we present such a rare and potential case of“to gain by loss”as a neomorphic mutation during soybean domestication for increasing seed weight.Using a population derived from a chromosome segment substitution line of Glycine max(SN14)and Glycine soja(ZYD06),a quantitative trait locus(QTL)of 100-seed weight(q HSW)was mapped on chromosome 11,corresponding to a truncatedβ-1,3-glucosidase(βGlu)gene.The novel gene hsw results from a 14-bp deletion,causing a frameshift mutation and a premature stop codon in theβGlu.In contrast to HSW,the hsw completely lostβGlu activity and function but acquired a novel function to promote cell expansion,thus increasing seed weight.Overexpressing hsw instead of HSW produced large soybean seeds,and surprisingly,truncating hsw via gene editing further increased the seed size.We further found that the core 21-aa peptide of hsw and its variants acted as a promoter of seed size.Transcriptomic variation in these transgenic soybean lines substantiated the integration hsw into cell and seed size control.Moreover,the hsw allele underwent selection and expansion during soybean domestication and improvement.Our work cloned a likely domesticated QTL controlling soybean seed weight,revealed a novel genetic variation and mechanism in soybean domestication,and provided new insight into crop domestication and breeding,and plant evolution.

成人住院患者失禁相关性皮炎结构化皮肤护理方案的证据总结

目的评价和总结成人住院患者失禁相关性皮炎(IAD)结构化皮肤护理方案的相关证据,为临床护理决策提供参考。方法计算机检索BMJ Best Practice、UpToDate、澳大利亚Joanna Briggs Institute循证卫生保健中心图书馆、加拿大安大略省注册护士协会网站、国际指南协作网、美国国立指南网、英国国家卫生与临床优化研究所、医脉通、Cochrane Library、PubMed、Web of Science、CINAHL、Embase、万方数据库、维普网、中国知网、中国生物医学文献数据库中与成人住院患者IAD结构化皮肤护理相关的临床决策、指南、证据总结、系统评价、专家共识。检索时限为建库至2021年4月30日。由2名研究者独立对所纳的证据进行质评价量和推荐级别评定。结果共纳入14篇文献,包括2篇临床决策、1篇实践指南、6篇证据总结、2篇系统评价、3篇专家共识;从构化皮肤护理的评估、清洁、保湿和隔离4个方面汇总了29条最佳证据。结论医护人员应将证据与临床情景、患者的偏好相结合,从而制订最佳的皮肤结构化护理临床决策,提高成人住院患者IAD的护理质量。

Responses of water use efficiency to phenology in typical subtropical forest ecosystems——A case study in Zhejiang Province

Ecosystem-scale water-use efficiency(WUE) is an important indicator for understanding the intimately coupled relationship between carbon and water cycles in ecosystems. Previous studies have suggested that both abiotic and biotic factors have significant effects on WUE in forest ecosystems. However, responses of WUE to phenology in the context of climate change remain poorly understood. In this study, we analyzed the sensitivity and response patterns of seasonal WUE to phenology in Zhejiang Province where typical subtropical forest ecosystems are located, and discussed potential causes of the changes of the sensitivity and response patterns along different climate gradient during 2000–2014. The results of interannual partial correlation analysis showed widespread negative correlations between WUE and the start of growing season(SOS) in spring. This is because the increase in gross primary product(GPP) is larger than that of evapotranspiration(ET), resulting from an advanced SOS. The positive correlation between WUE and SOS was widely observed in summer mainly because of water stress and plant ecological strategy. The autumn WUE enhanced with the delay in the end of growing season(EOS)mainly because of the increase in GPP meanwhile the decrease or steadiness in ET, resulting from a delayed EOS. In space, the sensitivity of spring WUE to SOS significantly decreased along the radiation gradient, which might be related to strong soil evaporation in high radiation area;the sensitivity of WUE to SOS in summer showed a positive correlation with precipitation and a negative correlation with temperature, respectively, which might be attributed to the compensation of GPP to the delayed SOS and water stress caused by high temperature. The sensitivity of WUE to EOS increased significantly along the radiation and precipitation gradients in autumn, which may be because the increase of radiation and precipitation provides more water and energy for photosynthesis.

Nitric oxide, g-aminobutyric acid, and mannose pretreatment influence metabolic profiles in white clover under water stress

Nitric oxide(NO),γ-aminobutyric acid(GABA),and mannose(MAS)could be important regulators of plant growth and adaptation to water stress.The application of sodium nitroprusside(SNP,a NO donor),GABA,and MAS improved plant growth under watersufficient conditions and effectively mitigated water stress damage to white clover.The metabonomic analysis showed that both SNP and GABA application resulted in a significant increase in myo-inositol content;the accumulation of mannose was commonly regulated by SNP and MAS;GABA and MAS induced the accumulation of aspartic acid,quinic acid,trehalose,and glycerol under water deficit.In addition,citric acid was uniquely up-regulated by SNP associated with tricarboxylic acid(TCA)cycle under water stress.GABAspecially induced the accumulation of GABA,glycine,methionine,and aconitic acid related to GABA shunt,amino acids metabolism,and TCA cycle in response to water stress.MAS uniquely enhanced the accumulation of asparagine,galactose,and D-pinitol in association with amino acids and sugars metabolism under water stress.SNP-,GABA-,and MAS-induced changes of metabolic profiles and associated metabolic pathways could contribute to enhanced stress tolerance via involvement in the TCA cycle for energy supply,osmotic adjustment,antioxidant defense,and signal transduction for stress defense in white clover.