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Along with the development of science and technology, chemical reactions exhibit an important role in various fileds including synthesis, chemical engineering, energy, environment, biology and medicine. The effective intermediates monitoring and mechanism exploration of chemical reactions can promote their development and contribute to the design of new chemical reactions. However, in the complex reaction matrix, a variety of intermediates with different molecular weights, life and dynamic changes will be generated at different reaction conditions, the effective capture and structure determinations of the short-lived and active reaction intermediates are hard to be achieved. In recent years, ambient mass spectrometry (AMS) has been widely used in the detection of chemical intermediates to explore reaction mechanisms, due to its advantages of high sensitivity, high selectivity, rapid analysis and in-situ monitoring. Herein, the research progress and development of AMS for the detection of reaction intermediates were reviewed, which involved the reactions in the fields of electrochemistry, photochemistry, plasma chemistry and microdroplet chemistry. For different types of reactions, the designs of different AMS detection technologies were introduced in details. Upon the different ionization strategies, different kinds of techniques have been reported, including desorption electrospray ionization mass spectrometry (DESI-MS), nano-electrospray ionization mass spectrometry (nESI-MS), extraction electrospray ionization mass spectrometry (EESI-MS), Venturi easy ambient sonic spray ionization mass spectrometry (VEASI-MS), spray-dependent plasma mass spectrometry (SDP-MS), accelerated plasma degradation coupled with electrospray ionization mass spectrometry (APD-MS), field-induced droplet ionization mass spectrometry (FIDI-MS) and so on. Subsequently, the progress and application of these mass spectrometry techniques in capturing intermediates of different kinds of reactions as well as the exploration of mechanisms were reviewed. Finally, the development of mass spectrometry for the detection of transient reaction intermediates in different chemical reactions, including electrochemical reactions, photochemical reactions, plasma reactions and microdroplet reactions were summarized and prospected. As reviewed, based on the characteristics of high throughput virtual screening and online monitoring, as well as the diversification of ion sources, AMS would be widely used in various fields including industrial production, environmental protection, energy and so on. In the future, the improved AMS techniques will be encouraged for examining more highly active intermediates with the increasing requirements for the examination of complicated reactions.

Along with the industrial development and human society progress, large number of pollutants have been discharged to induce the environmental pollution, which have attracted global attentions. To evaluate the environmental pollution and environmental effects, the fast, accurate, and reliable analytical methods are required for qualitative and quantitative analysis of pollutants. Ambient mass spectrometry (AMS) has the advantages of rapid, in-situ and real-time analysis of samples at ambient conditions, without any sample pretreatment. Herein, from the perspective of different ionization technologies, the applications of electrospray ionization mass spectrometry (ESI-MS), atmospheric pressure chemical ionization mass spectrometry (APCI-MS), as well as the corresponding coupling techniques for the detection of environmental water pollutants were reviewed. Finally, the development of ambient ionization mass spectrometry in the detection of environmental pollutants was summarized and prospected.

Objective To investigate the etiology, diagnosis and treatment of granulomatous cheilitis（GC）. Methods For a patient with recurrent granulomatous cheilitis for more than 1 year in whom no medical treatment was used, only systemic treatment of the teeth was performed, and its efficacy was observed. We also reviewed the relevant literature. Results The vermilion of the right lower lip of the patient was obviously swollen and soft. There was rebound and no pitting edema with palpation. A large dark red rash with local desquamation was observed on the skin over the right mandible. There were residual roots in tooth 35, 46, and 47, a porcelain bridge on 11-24, deep caries in 15, 16, 26, and 36, and many calculi in the whole mouth, and the gingival margin was obviously congested and swollen. Histopathological examination showed many lymphocytes infiltrated the superficial dermis, and granulation tissue, plasma cells and eosinophils infiltrated locally. The diagnosis was as follows: ① GC; ② 35, 46, and 47 residual roots; ③ 15, 16, 26, and 36 deep caries; ④ gingivitis. The treatment included extraction of 35, 46, and 47 residual roots, periodontal basic treatment, and fillings for 15, 16, 26, and 36. No drugs were administered except for 3 days after tooth extraction. After 5 weeks of treatment, the swelling of the lower lip and the skin rash completely disappeared. There was no recurrence in the follow-up observation at six months. Through a literature review and analysis, we found that GC may be related to various factors such as immunity, infection, and genetics. Local oral infections may be closely related to the incidence of GC. Conclusion Resolution of local oral infections is effective for the treatment of granulomatous cheilitis, and local oral infections may be closely related to the onset of granulomatous cheilitis. In the treatment of granulomatous cheilitis, attention should be paid to the systematic examination of the oral condition, and the treatment of suspected lesions in the oral cavity should begin in the early stages of treatment.

Single-atom catalysts (SACs) have attracted interest in photodynamic therapy (PDT), while they are normally limited by the side effects on normal tissues and the interference from the Tumor Microenvironment (TME). Here we show a TME-activated in situ synthesis of SACs for efficient tumor-specific water-based PDT. Upon reduction by upregulated GSH in TME, C3N4-Mn SACs are obtained in TME with Mn atomically coordinated into the cavity of C3N4 nanosheets. This in situ synthesis overcomes toxicity from random distribution and catalyst release in healthy tissues. Based on the Ligand-to-Metal charge transfer (LMCT) process, C3N4-Mn SACs exhibit enhanced absorption in the red-light region. Thereby, a water-splitting process is induced by C3N4-Mn SACs under 660 nm irradiation, which initiates the O2-independent generation of highly toxic hydroxyl radical (·OH) for cancer-specific PDT. Subsequently, the ·OH-initiated lipid peroxidation process is demonstrated to devote effective cancer cell death. The in situ synthesized SACs facilitate the precise cancer-specific conversion of inert H2O to reactive ·OH, which facilitates efficient cancer therapy in female mice. This strategy achieves efficient and precise cancer therapy, not only avoiding the side effects on normal tissues but also overcoming tumor hypoxia. The utility of single-atom catalysts (SACs) for photodynamic therapy (PDT) has been limited by tumor hypoxia and side effects on normal tissues. Here the authors address these issues by developing an approach of tumor microenvironment-activated in situ synthesis of SACs for tumor-specific water-based PDT. [ABSTRACT FROM AUTHOR]