Biomedical subjects

Huan Chen

Publications and source records attributed to Huan Chen.

4 recordsLinked to original sources

PubMed2026

Tigecycline-resistant Staphylococcus in waiting pens of a pig slaughterhouse: genomic insights into a food safety alert.

BACKGROUND: The waiting pens of slaughterhouses represent a critical control point in the 'farm-to-fork' continuum, yet their role in the emergence and dissemination of antimicrobial resistance remains understudied. This study investigated tigecycline-resistant Staphylococcus (TRS) in these high-risk zones to assess their prevalence, resistance mechanisms, and transmission dynamics. METHODS: 400 samples were collected from the waiting pens of a pig slaughterhouse in Guangzhou, China. Antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, and molecular cloning were employed to characterize resistance mechanisms and transmission patterns. RESULTS: 78 TRS strains were isolated and classified into three species, including S. borealis, S. ureilyticus, and S. pasteuri. These isolates exhibited multidrug-resistant phenotypes and carried new mutations in rpsJ and tet(M), which were functionally confirmed to reduce tigecycline susceptibility. Phylogenetic evidence demonstrated clonal transmission between pig farms and the slaughterhouse. The tet(M) gene was located within Staphylococcal cassette chromosome mec elements mediated by IS257, while tet(L) was carried by plasmids formed through IS256/IS257-mediated recombination. CONCLUSIONS: Waiting pens serve as crucial reservoirs for the amplification and dissemination of antimicrobial resistance. Our findings underscore the urgent need for enhanced biosecurity measures, improved waste management, and routine molecular surveillance in these high-risk zones to mitigate the spread of resistance along the food production chain.

Animals↗

PubMed2026

Single-cell transcriptomics reveals distinct microglial state remodeling associated with the (R)-nicotine/diosmetin combination and galantamine in LPS-challenged BV2 cells.

BACKGROUND: Microglial neuroinflammation contributes to the progression of neurodegenerative diseases, yet it remains challenging to attenuate inflammatory responses while preserving cellular function. The effects of (R)-nicotine, diosmetin, their combined administration, and galantamine on heterogeneous BV2 transcriptional states have not been compared at single-cell resolution. METHODS: LPS-stimulated BV2 microglial-like cells were treated with (R)-nicotine, diosmetin, their combination (DR), or galantamine. Single-cell RNA sequencing was performed with three biological replicates per group and integrated with RNA velocity and SCENIC regulon inference to characterize treatment-associated state redistribution, inferred local transcriptional directionality and regulon-activity patterns. Functional validation included CCK-8 metabolic activity assays, multiplex cytokine ELISA, BDNF/GDNF quantification, qPCR, and high-content immunofluorescence analysis of iNOS and Arg1 at single-cell resolution. RESULTS: LPS decreased the relative abundance of the Itgae+/Plk4+ cluster while increasing the Nmur1+/Limk2+ cluster and inflammatory effector programs. DR treatment suppressed pro-inflammatory cytokine release without significantly reducing CCK-8-assessed metabolic activity, increased the Itgae+/Plk4+ cluster proportion, and increased BDNF/GDNF relative to LPS. RNA velocity and SCENIC analyses suggested that DR and galantamine showed distinct transcriptional and regulatory patterns: DR attenuated Batf-associated inflammatory regulons and was associated with increased Atf3-linked stress-response activity, whereas galantamine preferentially engaged DNA repair and genome-maintenance programs. CONCLUSION: These findings indicate that the DR condition was associated with remodeling of LPS-challenged BV2 microglial-like states, attenuation of inflammatory programs, and increased neurotrophic outputs relative to LPS, without significantly reducing CCK-8-assessed metabolic activity. This study provides a single-cell characterization of distinct treatment-associated responses to (R)-nicotine, diosmetin, their combined administration, and galantamine.

Microglia↗

PubMed2026

Associations between multiple essential trace metal concentrations and risk of hyperuricemia: insights from a central Chinese population.

Previous studies have indicated that levels of individual essential trace metals are related to hyperuricemia (HUA), but evidence on their combined effects is limited. To address this gap, the associations of individual and joint levels of 12 essential trace metals (manganese, selenium, nickel, chromium, cobalt, tin, iron, molybdenum, zinc, strontium, vanadium, and copper) with the risk of HUA were investigated in 2,021 adults recruited from Hunan Province, China. Inductively coupled plasma mass spectrometry (ICP-MS) was employed to determine urinary metal concentrations. Logistic regression, Bayesian kernel machine regression (BKMR), and quantile g calculation (Qgcomp) were applied to evaluate the associations of single and mixture metal concentrations with HUA. Of the participants, 516 (25.53%) were diagnosed with HUA. Inverse associations were found between vanadium, chromium, manganese, iron, cobalt, selenium, strontium, and molybdenum levels and HUA, with ORs ranging from 0.63 to 0.91. Conversely, a positive association was observed between zinc concentration and HUA [OR (95% CI): 1.17 (1.01, 1.37)]. Both BKMR and Qgcomp models showed a negative overall effect of essential trace metals on HUA risk, with strontium (- 43.6%) and vanadium (- 27.8%) being the main contributors. In addition, formal interaction tests revealed significant effect modification by age for tin and by BMI for zinc. In conclusion, the levels of essential trace metals were linked to a decreased risk of HUA, and these associations were modified by age and BMI only for specific metals.

Humans↗

PubMed2024

ALDH1A1 promotes immune escape of tumor cells through ZBTB7B-glycolysis pathway.

The primary impediment to the success of immunotherapy lies in the immune evasion orchestrated by tumors, contributing to the suboptimal overall response rates observed. Despite this recognition, the intricacies of the underlying mechanisms remain incompletely understood. Through preliminary detection of clinical patient tissues, we have found that ALDH1A1 was a key gene for the prognosis of cancer patients and tumor glycolysis. In vitro experiments and tumor formation in nude mice suggested that targeting ALDH1A1 could inhibit tumor growth. Through further analysis of xenograft tumor models in immune-normal mice and flow cytometry, we found that deficiency in ALDH1A1 could promote immune system suppression of tumors in vivo. Specifically, RNA-seq analysis, combined with qPCR and western blot, identified the transcription factor ZBTB7B as downstream of ALDH1A1. The binding sites of the transcription factor ZBTB7B on the LDHA promoter region, which is responsible for regulating the rate-limiting enzyme gene LDHA in glycolysis, were determined using luciferase reporter gene detection and Chip-qPCR, respectively. In addition, the increased SUMOylation of ZBTB7B stabilized its transcriptional activity. Further in vivo and in vitro experiments confirmed that the combination of targeting ALDH1A1 and ZBTB7B with immune checkpoint inhibitors could synergistically inhibit tumors in vivo. Finally, after conducting additional verification of patient tissue and clinical data, we have confirmed the potential translational value of targeting ALDH1A1 and ZBTB7B for tumor immunotherapy. These results emphasize the potential translational significance of targeting ALDH1A1 and ZBTB7B in the realm of tumor immunotherapy. The convergence of ALDH1A1 inhibition and immune checkpoint blockade, particularly with PD-L1/PD-1 mAb, presents a compelling avenue for curtailing tumor immune escape.

Animals↗