Evaluating the diagnostic value of using metagenomic next-generation sequencing on bronchoalveolar lavage fluid and tissue in infectious pathogens located in the peripheral lung field.

BACKGROUND: Metagenomic next-generation sequencing (mNGS) exerts a vital part in accurately diagnosing pulmonary infection. However, the diagnostic value of different samples obtained by virtual bronchoscopic navigation (VBN) combined with mNGS for pathogen detection in infections located in the peripheral lung field (PLF) is still unclear. METHODS: Patients infected from July 2018 to February of the following year were carefully analyzed and divided into two parts, namely, non-infectious disease group and the infectious disease group. Then bronchial expansion tests were performed for each subject, collected liquid specimens and tissue standards, and conducted regular mNGS and microbiological detection and analysis. The value of mNGS and culture in pathogen detection was compared, at the same time, the performance of tissue mNGS and bronchoalveolar lavage fluid (BALF) mNGS in the diagnosis process was compared. When discrete variables were processed, Pearson χ2 and Fisher's exact test could be used to perform categorical variables analysis. Continuous variables were analyzed and compared by Mann-Whitney U test. RESULTS: After mNGS diagnosis, Acinetobacter baumannii, Pseudomonas aeruginosa and Rothia mucilaginosa were the bacterial species showing the highest abundances. In addition, mNGS achieved the sensitivities in the detection of pathogens in tissues and BALF of 72.9% and 81.4%, respectively, and it is higher than conventional culture. Bacterial diagnostic sensitivity was significantly different between BALF and tissue using mNGS (95.0% vs. 62.5%, P=0.03). The sensitivity and specificity of BALF in detecting fungal infections were not significantly different from those of mNGS. A consistency test showed that these two methods had some degree of consistency (k=0.673, P=0.000). CONCLUSIONS: This study showed that the mNGS in BALF samples and the mNGS in tissue samples which could be used to test for pathogens in the lungs. The sensitivity will increase when mNGS is combined with culture. Also, mNGS of BALF and tissues had some degree of consistency to detect fungal infections, whereas mNGS of BALF had better sensitivity to detect bacterial infection than mNGS of tissues.

Visible light-promoted intermolecular cyclization/aromatization of chalcones and 2-mercaptobenzimidazoles via an EDA complex and a mechanism study.

Visible-light-promoted cyclization and aromatization of chalcones with 2-mercaptobenzimidazoles have been successfully developed to obtain diverse imidazo[2,1-b]thiazoles, and C-S and C-N bonds were constructed in one step. The reaction uses oxygen in the air as an oxidant, and the method does not need an external photocatalyst or a transition metal catalyst. The strategy features mild conditions, a simple system, readily accessible feedstocks, and a friendly environment. UV absorption spectroscopy and control experiments have shown that the reaction mechanism involves the formation of an electron-donor-acceptor (EDA) complex from thiolate anions and chalcones. In order to verify the mechanism, we studied the structure and HOMO/LUMO of the EDA complex by density functional theory (DFT) calculations. The results show that the π-π stacking between chalcones and 2-mercaptobenzimidazoles will cause a red shift of the UV absorption wavelength in the presence of Cs2CO3, and also provide a theoretical basis for the electron transfer of EDA complexes.

Critical Review of Synthesis, Toxicology and Detection of Acyclovir.

Acyclovir (ACV) is an effective and selective antiviral drug, and the study of its toxicology and the use of appropriate detection techniques to control its toxicity at safe levels are extremely important for medicine efforts and human health. This review discusses the mechanism driving ACV's ability to inhibit viral coding, starting from its development and pharmacology. A comprehensive summary of the existing preparation methods and synthetic materials, such as 5-aminoimidazole-4-carboxamide, guanine and its derivatives, and other purine derivatives, is presented to elucidate the preparation of ACV in detail. In addition, it presents valuable analytical procedures for the toxicological studies of ACV, which are essential for human use and dosing. Analytical methods, including spectrophotometry, high performance liquid chromatography (HPLC), liquid chromatography/tandem mass spectrometry (LC-MS/MS), electrochemical sensors, molecularly imprinted polymers (MIPs), and flow injection-chemiluminescence (FI-CL) are also highlighted. A brief description of the characteristics of each of these methods is also presented. Finally, insight is provided for the development of ACV to drive further innovation of ACV in pharmaceutical applications. This review provides a comprehensive summary of the past life and future challenges of ACV.