Cation exchange chromatography, as a commonly used separation and purification technique in biopharmaceutical manufacturing, is often employed for downstream processes to separate target monoclonal antibodies from their charge variants. For samples with complex and poorly resolved charge variant profiles, the collection solely based on ultraviolet detection does not provide specific compositional information for individual charge variants, making it challenging to determine the range of pooled fractions directly. Subsequent laborious fractionation analysis is then required to guide collection according to production requirements. A mechanistic model for the cation exchange chromatography process of the target monoclonal antibody's critical components was established, and it was employed to assist in product collection. The model accurately predicted the elution peak shapes of the modeled variants, with a root mean square error between predicted and actual values below 0.009. In comparison to the online ultraviolet-based collection method, the model-assisted collection method not only visualized the chromatographic process but also increased the relative productivity by fourfold while ensuring compliance rate.

The effect of different concentrations of glycyrrhizic acid (GA) and Zn²⁺ on the self-assembly of metal complexes was investigated by forming metal complexes, and the properties and assembly mechanisms of the formed carrier-free supramolecular hydrogel were characterised. Scanning electron microscopy (SEM) and zeta potential were used to characterise the microscopic morphology and stability of the GA-Zn complex hydrogel, which had spherical-like particles of about 1 μm with good stability; the rheometer was used to detect its materialistic properties, which showed excellent stability, self-healing property and reversibility; through in vitro bacterial inhibition, it was found that the GA-Zn carrier-free supramolecular hydrogel has enhanced bacterial inhibition function after assembly. The hydrogel was also found to possess both anti-inflammatory and antioxidant efficacy when evaluated using LPS and H₂O₂ induced RAW 264.7 cell damage models, respectively. The above results suggest that GA-Zn hydrogel not only has good materialistic properties, but also possesses good antibacterial, anti-inflammatory and antioxidant activities, which has the value of clinical research as a carrier-free multi-functional antimicrobial dressing, and the present study provides a reference for the discovery of novel biomedical materials from active molecules of natural traditional Chinese medicine.

WRKY transcription factor is a type of transcription factor unique to plants and plays an important role in various physiological processes of plants. This study is based on the transcriptome data of Atractylodes lancea, the correlation between the FPKM values of the AlWRKY gene and the AlTPS gene of Atractylodes lancea was analyzed. Combined with the analysis results, the candidate gene AlWRKY65 with a significant positive correlation with the expression levels of AlTPS1 and AlTPS6 genes and a relatively high FPKM value was screened. The candidate gene was cloned to obtain the open reading frame ORF of the AlWRKY65 gene, and the related information of its encoded protein was analyzed and the gene expression was studied. The results showed that AlWRKY65 contains a 681 bp open reading frame and encoding 226 amino acids. Through amino acid sequence homology analysis, it was found that AlWRKY65 amino acid sequence had high homology with several plants such as HaWRKY65 and LsWRKY65; AlWRKY65 protein had a typical WRKYGQK domain, belonging to IIe subgroup of WRKY transcription factor family; phylogenetic analysis indicated that AlWRKY65 protein had the higher homology with CcWRKY65 protein; the expression of AlWRKY65 gene in different tissues of two producing areas of Atractylodes lancea were assayed via real-time fluorescence quantitative PCR, and the results showed that all of them were highly expressed in leaves and also has tissue differences. The expression level of AlWRKY65 gene was down-regulated within 48 h of methyl jasmonate (MeJA) induction; subcellular localization and transcriptional activation assay suggested that AlWRKY65 was located in the nucleus and had no transcriptional activation activity. This study provides a reference for further elucidating the biological function of AlWRKY65 in Atractylodes lancea.

Antibody-drug conjugate (ADC) has become an effective method for treating various diseases, especially cancer, due to its clear target and good selectivity in clinical practice. However, the monoclonal antibodies in traditional ADC have poor tissue permeability, high modification costs, pose risks such as immunogenicity and immunotoxicity. The nanobody (Nb) which is extracted from the blood of camel animals, is the smallest antibody fragment known to have complete antigen binding ability. It has advantages such as strong tissue permeability, strong specificity, low immunogenicity, and high stability, and can replace traditional monoclonal antibodies to participate in the construction of nanobody-drug conjugate (NDC). This article reviews and discusses the advantages of Nb structure, the construction and application of NDC in the hope of providing ideas for the research and development of NDC.

Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

Bacterial resistance has always been a challenge in the field of antibacterials research. As one of the most problematic pathogens causing nosocomial infections, Acinetobacter baumannii (A. baumannii) was a severe threaten to public health. In recent years, as the rate of multidrug-resistant, extensively drug-resistant, and even pan drug-resistant A. baumannii has been increasing, there is an urgent need to develop new strategies to combat this pathogen. Iron is an essential element for the survival and the infection process of A. baumannii. Bacteria have developed a series of iron uptake strategies to survive in conditions of the host iron starvation, including the secretion of siderophore for iron chelation, the uptake of ferroheme, and the transport of ferrous by Feo system. Developing antibacterial strategies to inhibit the iron uptake is an effective way to deal with A. baumannii infection. This article will review the mechanisms of iron uptake by A. baumannii and the antimicrobial strategies developed based on them.

Microsporidia is a group of intracellular parasitic eukaryotic microorganisms that pose threats to livestock fish production and human health, but there is no special chemo-therapeutic drug available for the treatment of microsporidia currently. In this study, sulfonamide derivatives of spectinomycin were designed by taking into consideration the low toxicity of spectinomycin and the favorable pharmaceutical properties of sulfonamides. Through the exploration of reaction conditions, a total of 21 target molecules were synthesized with a yield of 52%-74% and their chemical structures were confirmed by ¹H NMR, ¹³C NMR, and high resolution mass spectrometry (HR MS). By screening in vitro, the host cell cytotoxicity and biological activity of target molecules to Encephalitozoon hellem, a representative of vertebrates infecting microsporidia, were studied. It was found that four target molecules each could inhibit or promote the proliferation of E. hellem. In this study, the synthesis method of sulfonamide derivatives of spectinomycin was established, and new compounds effective against E. hellem were discovered, which provided a new idea for the further derivatization of spectinomycin and the development of therapeutic drugs targeting microsporidia.

Kynurenine 3-monooxygenase (KMO) is a key rate-limiting enzyme in the downstream catabolism of kynurenine pathway (KP). Under the catalysis of KMO, the intermediate product kynurenine is metabolized into various active metabolites, including 3-hydroxykynurenine (3-HK), quinolinic acid (QA) and nicotinamide adenine dinucleotide (NAD⁺). More and more studies have shown that abnormal KMO expression activity mediates KP metabolic disorders, and is involved in the occurrence and development of nervous system diseases, autoimmune diseases, infectious diseases and tumors, suggesting that KMO can be used as a potential and effective drug therapeutic target. This article focuses on the role of KMO in the pathological mechanism of various diseases, and summarizes the existing KMO inhibitors to provide methods and ideas for targeted KMO therapy.

The study utilized spectral correlation analyses combined with bioactivity evaluation to examine the effective components of antidepressants in the Baihe Dihuang decoction. Firstly, the chemical fingerprints for different extraction parts in the Baihe Dihuang decoction were achieved using HPLC and UHPLC-MS technology. Then, in order to evaluate the antidepressant effect of Baihe Dihuang decoction, the animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Hunan University of Chinese Medicine (No. LLBH-202104270001), in compliance with the Institutional Animal Care Guidelines. We recorded the distance of autonomous movement of mice in open field experiment, the immobility time of tail suspension test, and the forced swimming. Additionally, we measured the content of neurotransmitters. Finally, Pearson analysis, grey correlation analysis, and orthogonal partial least squares regression analysis were utilized to establish the correlation between antidepressant efficacy indicators and fingerprinting. The spectrum-effect relationship results were confirmed through the in vitro activity verification. This study demonstrated that regaloside A, B, C, catalpol, and Isoacteoside might be the main antidepressant components in Baihe Dihuang decoction. Furthermore, it was found that using diverse mathematical models and bioactivity evaluation could enhance the accuracy of the spectral correlation analyses results.

The abuse of novel phenylcyclohexylpyridine drugs poses a significant threat to societal safety. The novel psychoactive substance 2-methyl-deschloroketamine (2-MDCK), belonging to the phenylcyclohexylpyridine class, has recently surfaced as a new compound. However, there is a lack of understanding regarding its metabolic pathways and the identification of suitable biomarkers. In this study, a human liver microsomal model was established, and ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) technology was applied to investigate the in vitro metabolism and products of 2-MDCK. The results indicate that 2-MDCK undergoes various metabolic reactions, including dehydrogenation, deamination, hydroxylation, and demethylation, leading to the formation of eight metabolites. By conducting actual testing on hair samples from 2-MDCK abusers, the existence of six metabolites was confirmed. Comparing the metabolic products in the liver microsomal in vitro model, M3.1 and M4.1 were identified as biomarkers for 2-MDCK consumption. Five samples of abusers of 2-methyl-dechloroketamine were provided by the Anti-Drug Brigade of the Hangzhou Public Security Bureau. Negative hair samples were provided by laboratory volunteers, and all samples were obtained with the informed consent of the volunteers. These findings provide a scientific basis for the detection and identification of 2-MDCK and its metabolites, as well as crucial support for the study of the metabolic mechanisms of similar novel psychoactive substances in the phenylcyclohexylpyridine class. This research holds significant importance in addressing the issue of abuse of new psychoactive substances.