Principles of environmentally-sustainable anaesthesia: a global consensus statement from the World Federation of Societies of Anaesthesiologists

The Earth’s mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists’ education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references.     

Diffusion-weighted magnetic resonance imaging in rat kidney using two-dimensional navigated,interleaved echo-planar imaging at 7.0 T

The purpose of this study was to investigate the feasibility of two-dimensional (2D) navigated, interleaved multishot echo-planar imaging (EPI) to enhance kidney diffusion-weighted imaging (DWI) in rats at 7.0 T. Fully sampled interleaved four-shot EPI with 2D navigators was tailored for kidney DWI (Sprague–Dawley rats, n = 7) on a 7.0-T small bore preclinical scanner. The image quality of four-shot EPI was compared with T₂-weighted rapid acquisition with relaxation enhancement (RARE) (reference) and single-shot EPI (ss-EPI) without and with parallel imaging (PI). The contrast-to-noise ratio (CNR) was examined to assess the image quality for the EPI approaches. The Dice similarity coefficient and the Hausdorff distance were used for evaluation of image distortion. Mean diffusivity (MD) and fractional anisotropy (FA) were calculated for renal cortex and medulla for all DWI approaches. The corticomedullary difference of MD and FA were assessed by Wilcoxon signed-rank test. Four-shot EPI showed the highest CNR among the three EPI variants and lowest geometric distortion versus T₂-weighted RARE (mean Dice: 0.77 for ss-EPI without PI, 0.88 for ss-EPI with twofold undersampling, and 0.92 for four-shot EPI). The FA map derived from four-shot EPI clearly identified a highly anisotropic region corresponding to the inner stripe of the outer medulla. Four-shot EPI successfully discerned differences in both MD and FA between renal cortex and medulla. In conclusion, 2D navigated, interleaved multishot EPI facilitates high-quality rat kidney DWI with clearly depicted intralayer and interlayer structure and substantially reduced image distortion. This approach enables the anatomic integrity of DWI-MRI in small rodents and has the potential to benefit the characterization of renal microstructure in preclinical studies.     

半夏泻心汤对DSS诱导的溃疡性结肠炎小鼠肠道微生态及Th17/Treg细胞平衡的影响＊

目的 观察半夏泻心汤对饮用葡聚糖硫酸钠（DSS）诱导建立的溃疡性结肠炎（UC）模型小鼠Th17/Treg细胞平衡及肠道微生态的影响，从免疫失衡及菌群紊乱角度分析半夏泻心汤治疗UC的作用机制。方法 将40只C57BL/6J雄性小鼠随机分为空白组、模型组、阳性药（美沙拉嗪）组及半夏泻心汤组，除空白组外的各小鼠采用2.5% DSS水溶液自由饮用7天诱导建立UC小鼠模型。自实验第8日起，分别采用灭菌水、美沙拉嗪水溶液、半夏泻心汤水溶液给上述各组别小鼠灌胃。采用HE染色观察结肠组织病理学变化，ELISA方法检测组织炎症因子含量，流式细胞术检测Th17及Treg细胞的相对数量，16S rRNA测序技术进一步检测模型小鼠粪便中菌群的变化。结果 与空白组比较，模型组小鼠结肠损伤严重，血清炎症因子含量显著升高（P<0.01）；与模型组比较，中药干预组小鼠结肠损伤减轻，血清TNF-α、IFN-γ含量显著下降（P<0.05）。较空白组小鼠相比，模型组小鼠Th17细胞百分比显著升高（P<0.01），而Treg细胞百分比显著降低（P<0.01）。经半夏泻心汤干预后，其小鼠Th17细胞数量均显著降低（P<0.05），Treg细胞数量则显著升高（P<0.05）。同时，半夏泻心汤可升高门水平上Firmicutes、属水平上Lachnospiraceae_NK4A136_group、unclassified_f_Lachnospiraceae、Prevotellaceae_UCG-001、Alistipes；降低门水平上Actinobacteriota，科水平上Bifidobacteriaceae、Atopobiaceae、Clostridiaceae，属水平上Clostridium_sensu_stricto_1、Coriobacteriaceae_UCG-002、Bifidobacterium的相对丰度。结论 半夏泻心汤可使Treg细胞相对数量升高、Th17细胞相对数量降低，以维持Th17/Treg细胞动态平衡；同时可降低有害菌Clostridium_sensu_stricto_1、Coriobacteriaceae_UCG-002的相对丰度，升高产短链脂肪酸类菌Lachnospiraceae_NK4A136_group、Prevotellaceae_UCG-001、unclassified_f_Lachnospiraceae等菌属的相对丰度，调控肠道微生物结构及动态平衡，从而发挥治疗UC的作用。     

CRISPR-Cas系统在动物及植物中不同的递送方式研究进展*

CRISPR-Cas 系统的发现彻底改变了基因编辑技术领域，在多方面都有着广阔的前景。该系统主要有Cas 蛋白和单链向导RNA 组成，其功能的发挥高度依赖于各组分的有效递送。本篇综述对目前动植物中该系统组分 的常用递送方式进行详细总结，并分析其目前仍存在的问题。