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Mass spectrometry (MS) has become an essential analytical method in every sector of science and technology. Because of its unique ability to provide direct molecular structure information on analytes, an extra method is rarely required. This review describes fabrication of a variable-pressure hollow cathode discharge (HCD) ion source for MS in detection, quantification and investigation of gas-phase ion molecule reactions of explosives and related compounds using air as a carrier gas. The HCD ion source has been designed in such a way that by altering the ion source pressures, the system can generate both HCD and conventional GD. This design enables for the selective detection and quantification of explosives at trace to ultra-trace levels. The pressure-dependent HCD ion source has also been used to investigate ion-molecule reactions in the gas phase of explosives and related compounds. The mechanism of ion formation in explosive reactions is also discussed. [ABSTRACT FROM AUTHOR]

Constituted by various heterogeneous cells, the tumor microenvironment (TME) is capable of promoting tumor proliferation, invasion, and metastasis through extensive crosstalk. The pivotal factor influencing the survival time of patients and their response to immunotherapy lies in the intratumoral immune environment. We obtained 112 differential genes related to T cell-mediated tumor killing in LUAD by employing bioinformatics analysis on the basis of the TCGA and TISIDB databases. Then the 6-gene prognostic risk score model (CA9, OIP5, TIMP1, SEC11C, FURIN, and TLR10) was constructed by conducting univariate LASSO as well as multivariate Cox regression analyses. The median risk score was taken as the threshold to classify the samples into two groups. Survival analysis revealed that the low-risk group exhibited a more favorable prognosis. Subsequently, the Cox regression analysis combined with clinical information (age, gender, and pathological stage) and the risk score of LUAD patients demonstrated the potential of this model as an independent prognostic factor. The nomogram established based on clinical information and a risk score in combination with the calibration curve indicated that this model had good predictive ability. Notable enrichment of the differential genes from the high- and low-risk groups was discovered in immune-associated processes or pathways, as shown by the GO and KEGG enrichment analyses. The combined use of single-sample gene enrichment analysis (ssGSEA) and immunophenoscore (IPS) demonstrated heightened immune infiltration and IPS scores in the low-risk group, indicating that immunotherapy was likely to show good efficacy in patients from this group. To sum up, the prognostic model of LUAD constructed based on T-cell-mediated cell killing-related genes was not only capable of screening the prognosis of LUAD patients but was also used for screening those LUAD patients with high sensitivity to immunotherapy. Our study offered novel insights into the clinical treatment and prognostic prediction of LUAD patients. [ABSTRACT FROM AUTHOR]

To improve the sensitivity of seawater refractive index (RI) measurement, fluorine-doped fiber (FDF)-sandwiched Mach–Zehnder interferometer (MZI) is proposed, which is fabricated by splicing a short section of FDF between two sections of single-mode fibers (SMFs) with a large lateral offset. In FDF-sandwiched MZI, the two light paths are the FDF cladding and the measured seawater. The FDF cladding has lower RI than that of normal single-mode fiber (SMF), so the FDF-sandwiched MZI has higher sensitivity than that of SMF-sandwiched MZI. The results show that the RI sensitivity of the proposed sensor can be up to −14,638 nm/RIU, which is about 10.9% higher than that of SMF-sandwiched MZI. Temperature cross-sensitivity of our sensor is only 1.7 × 10−6 RIU/°C. The proposed sensor has the potential application in real physical, chemical, and biological sensing. [ABSTRACT FROM AUTHOR]

Abstract Mass spectrometry (MS) is a formidable analytical tool for the analysis of non-polar to polar compounds individually and/or from mixtures, providing information on the molecular weights and chemical structures of the analytes. During the last more than one-decade, ambient ionization mass spectrometry (AIMS) has developed quickly, producing a wide range of platforms and proving scientific improvements in a variety of domains, from biological imaging to quick quality control. These methods have made it possible to detect target analytes in real time without sample preparation in an open environment, and they can be connected to any MS system with an atmospheric pressure interface. They also have the ability to analyze explosives, illicit drugs, disease diagnostics, drugs in biological samples, adulterants in food and agricultural products, reaction progress, and environmental monitoring. The development of novel ambient ionization techniques, such as probe electrospray ionization, paper spray ionization, and fiber spray ionization, employed even at picolitre to femtolitre solution levels to provide femtogram to attogram levels of the target analytes. The special characteristic of this ambient ion source, which has been extensively used, is the noninvasive property of PESI of examination of biological real samples. The results in the current review supports the idea that AIMS has emerged as a pioneer in MS-based approaches and that methods will continue to be developed along with improvements to existing ones in the near future. [ABSTRACT FROM AUTHOR]

AbstractMolecular information can be acquired from sample surfaces in real time using a revolutionary molecular imaging technique called mass spectrometry imaging (MSI). The technique can concurrently provide high spatial resolution information on the spatial distribution and relative proportion of many different compounds. Thus, many scientists have been drawn to the innovative capabilities of the MSI approach, leading to significant focus in various fields during the past few decades. This review describes the sampling protocol, working principle and applications of a few non-ambient and ambient ionization mass spectrometry imaging techniques. The non-ambient techniques include secondary ionization mass spectrometry and matrix-assisted laser desorption ionization, while the ambient techniques include desorption electrospray ionization, laser ablation electrospray ionization, probe electro-spray ionization, desorption atmospheric pressure photo-ionization and femtosecond laser desorption ionization. The review additionally addresses the advantages and disadvantages of ambient and non-ambient MSI techniques in relation to their suitability, particularly for biological samples used in tissue diagnostics. Last but not least, suggestions and conclusions are made regarding the challenges and future prospects of MSI. [ABSTRACT FROM AUTHOR]

AbstractBackgroundMethodsResultsConclusionTo explore the effect of Ganshuang granule on anti-alcoholic and anti-hangover and its potential mechanism.SPF SD rats’ drunken model and SPF Kunming mice’s hangover model were used as models.Ganshuang granule could significantly reduce sleep time, the time to climb in mice, and significantly prolong the tolerance time and shorten sleep time in rats (p < 0.05). The blood ethanol concentration of rats in each administration group was lower than that in the model group at each time point (p < 0.05). Compared with the control group, the activities of ADH and ALDH in the liver of the model group were significantly decreased (p < 0.05); the content of DA and 5-HT in the striatum of the model group was significantly increased (p < 0.05); and the activity of AchE in the hippocampus was significantly decreased (p < 0.05). The above processes could be improved and regulated in the drug administration group. Compared with the control group, there was no significant difference between ADH and ALDH in the serum of the model group (p > 0.05). However, the activities of ADH and ALDH in the liver of drunk rats could be upregulated by Ganshuang granule (p < 0.05).Ganshuang granule has the pharmacological effects of anti-alcoholic and anti-hangover, which is related to regulating the activities of ADH and ALDH in the liver, the contents of DA and 5-HT in striatum, and the activity of AchE in the hippocampus. [ABSTRACT FROM AUTHOR]