AME证据系列001--转化医学协会:脓毒症诊断和早期识别的临床实践指南

脓毒症是一种由感染引起的异质性疾病,感染触发了一系列复杂的局部或者全身的免疫炎症反应,引起多器官功能衰竭,发病率和病死率显著升高。由于至今仍然没有诊断脓毒症的金标准,所以脓毒症的临床诊断仍是一个难题。因此,脓毒症的临床诊断需要不断改变来满足临床和研究的要求。然而,尽管有许多新型的生物标记和筛选工具去预测脓毒症发生的风险,但是这些措施的诊断价值和有效性不足以让人满意,并且没有充分的证据去建议临床使用这些新技术。因此,脓毒症的临床诊断标准需要定期更新去适应不断产生的新证据。这篇综述旨在呈现当前脓毒症的诊断和早期识别方面的最新研究证据。临床运用不同的诊断方法的推荐意见依赖于推荐、评价、发展和评估分级体系(Grades of Recommendation Assessment,Development and Evaluation,GRADE),因为大部分的研究是观察性研究,并没有对这些方法进行可靠评估,采用的是两步推理方法。未来需要更多研究来确认或者反驳某一特殊的指标检测,同时应该直接采用相关病人的结果数据。

Bright betatron radiation from direct-laseraccelerated electrons at moderate relativistic laser intensity

Direct laser acceleration(DLA)of electrons in a plasma of near-critical electron density(NCD)and the associated synchrotron-like radiation are discussed for moderate relativistic laser intensity(normalized laser amplitude a0≤4.3)and ps length pulse.This regime is typical of kJ PW-class laser facilities designed for high-energy-density(HED)research.In experiments at the PHELIX facility,it has been demonstrated that interaction of a 1019 W/cm2 sub-ps laser pulse with a sub-mm length NCD plasma results in the generation of high-current well-directed superponderomotive electrons with an effective temperature ten times higher than the ponderomotive potential[Rosmej et al.,Plasma Phys.Controlled Fusion 62,115024(2020)].Three-dimensional particle-in-cell simulations provide good agreement with the measured electron energy distribution and are used in the current work to study synchrotron radiation from the DLA-accelerated electrons.The resulting x-ray spectrum with a critical energy of 5 keV reveals an ultrahigh photon number of 731011 in the 1–30 keV photon energy range at the focused laser energy of 20 J.Numerical simulations of betatron x-ray phase contrast imaging based on the DLA process for the parameters of a PHELIX laser are presented.The results are of interest for applications in HED experiments,which require a ps x-ray pulse and a high photon flux.

Stachytarpheta cayennensis Aqueous Extract,a New Bioreactor towards Silver Nanoparticles for Biomedical Applications

This study reports the preparation and characterization of silver nanoparticles synthesized by the mediation of the plant weed Stachytarpheta cayennensis through solution method. Ultraviolet visible spectroscopy (UV-Vis) determines the presence of nanoparticles in the solution. Infrared spectroscopy (IR) proves organic molecules at the particles interface. Powder X-ray diffraction (PXRD) provides phase composition and crystallinity. Shape was showed by scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) demonstrated the elemental mapping of the silver nanoparticles. Hydrogen peroxide scavenging and phosphomolybdenum antioxidant assays, egg albumin denaturation anti-inflammation study, and the formation mechanism complete the study. The particles have been found composed of pure silver Ag and silver chloride AgCl nanocrystallites. The average crystallite sizes were found to be 13 nm and 20 nm for Ag and AgCl respectively. A Rietveld refinement based XRD pattern data followed by Williamson-Hall plot allows a size and strain analysis. Based on SEM, spherical agglomerates materials were formed and EDX proved the presence of Cl- ions. The reaction formation mechanism of Ag and AgCl is proposed to be simultaneous and competitive. The silver nanoparticles moderately inhibit the denaturation of egg albumin and exhibit antioxidant action;hence, the nanoparticles could be considered as a potential source for biomedical applications.

PGR5-PGRL1-Dependent Cyclic Electron Transport Modulates Linear Electron Transport Rate in Arabidopsis thaliana

Plants need tight regulation of photosynthetic electron transport for survival and growth under environ- mental and metabolic conditions. For this purpose, the linear electron transport （LET） pathway is supple- mented by a number of alternative electron transfer pathways and valves. In Arabidopsis, cyclic electron transport （CET） around photosystem I （PSI）, which recycles electrons from ferrodoxin to plastoquinone, is the most investigated alternative route. However, the interdependence of LET and CET and the relative importance of CET remain unclear, largely due to the difficulties in precise assessment of the contribution of CET in the presence of LET, which dominates electron flow under physiological conditions. We there- fore generated Arabidopsis mutants with a minimal water-splitting activity, and thus a low rate of LET, by combining knockout mutations in Psb01, PsbP2, PsbQ1, PsbQ2, and PsbR loci. The resulting 45 mutant is viable, although mature leaves contain only ~20% of wild-type naturally less abundant Psb02 protein. 45 plants compensate for the reduction in LET by increasing the rate of CET, and inducing a strong non-photochemical quenching （NPQ） response during dark-to-light transitions. To identify the molecular origin of such a high-capacity CET, we constructed three sextuple mutants lacking the qE component of NPQ （45 npq4-1）, NDH-mediated CET （45 crr4-3）, or PGR5-PGRLl-mediated CET （45 pgrS）. Their analysis revealed that PGR5-PGRLl-mediated CET plays a major role in ~pH formation and induction of NPQ in C3 plants. Moreover, while pgr5 dies at the seedling stage under fluctuating light conditions, 45 pgr5 plants are able to survive, which underlines the importance of PGR5 in modulating the intersystem electron transfer.