Based on the theory of toxin in The Inner Canon of Yellow Emperor （《黄帝内经》）， this paper explores the concept and connotation of toxin from several aspects， including medicinal toxicity， pathogenic toxicity， pathoge-nesis and treatment of toxin pathogen. It explores the mechanism and significance of using toxin substances in curing and inducing diseases， sorts out the etiological and pathological evolution of toxic pathogens， clarifies the derivation and differentiation process from external toxins to internal toxins， and elucidates the interactions between toxin and other pathogenic factors such as phlegm， stasis， dampness， and fire. It further distinguishes the logical hierarchy of toxin caused by metabolic disorders such as sugar， fat， and drowning， clarifies that the essence of the etiology of "hidden toxin"， and determines the corresponding treatment principles and methods for toxic pathogens. It establishes a theoretical framework of traditional Chinese medicine toxic pathogen theory， providing theoretical basis for the clinical treatment of many diseases.

Aquaporin 5(AQP5)is a specific protein that can significantly increase the water permeability of cell membrane,partici-pate in the process of water secretion and absorption,maintain the balance of water molecules inside and outside the cell,and transport water across the membrane.Programmed cell death(PCD)is closely associated with the development and progression of Sj?gren's syn-drome(SS).AQP5 may influence the development and progression of SS by regulating the PCD mechanism.This article reviews the mo-lecular mechanisms of AQP5 in regulating the apoptosis,pyroptosis,autophagy,and ferroptosis of cells in recent years and discusses the potential influence of AQP5 on SS,in order to provide a theoretical basis for the clinical prevention and treatment of SS.

Sjogren's syndrome (SS) is a kind of connective tissue disease with high incidence and difficult to be treated, which belongs to the category of "dryness-arthralgia" in TCM. Xuanfu is a micro-concept of TCM, and is widely distributed and has the properties of "gateway" and "road", playing the role of circulating gas-liquid and operating spirit mechanism. Aquaporin (AQP) is a membrane-specific transmembrane protein that is widely distributed throughout the body and controls the movement of water, ions and gases in and out of cells. In recent years, the Xuanfu theory and AQP have played an important role in the etiology, pathogenesis, and treatment of SS. This article explored the etiology, pathogenesis, and treatment of SS by listing the correlation between Xuanfu and AQP in terms of structure and function, providing more theoretical basis for the application of Xuanfu theory in the treatment of SS.

Objective To study environmental safety reference standard values of commonly encountered pathogenic microorganisms, and provide the basis for environmental risk assessment of a high-level biosafety laboratory (BSL).Methods Using human exposure dose calculation methods as the basic principle in combination with microbial hazard evaluation methods , an infectious dose calculation model of human exposure to pathogenic microorganisms by breathing was proposed . Based on research on characteristics of commonly encountered pathogenic microorganisms at home and abroad , the environ-mental safety threshold reference standard and environmental risk protection zone for such microorganisms were obtained . Results An the environmental risk assessment standard calculation method for commonly encountered highly pathogenic microorganisms was proposed , and the minimum infectious dose and environmental safety threshold of seven commonly encountered pathogenic microorganisms were obtained , including SARS coronavirus , highly pathogenic avian influenza virus, Mycobacterium tuberculosis, Bacillus anthracis, Yersinia pestis,Francisella tularensis, and epidemic hemorrhagic fever virus.Conclusion The results can be used as a reference standard of infectious aerosols in a high-level BSL for environ-mental risk assessment , laboratory risk control and emergency management .