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Biomedical subjects

Xu Li

Publications and source records attributed to Xu Li.

8 recordsLinked to original sources

Influence of Repeated-Sprint Bout Duration in Sprint Interval Training Intervention on Physical Performance Adaptations of Young Volleyball Players.

The objective of this study was to examine the effects of repeated-sprint training (RST) with varying bout durations on the physical fitness adaptations of young male volleyball players. Forty athletes were randomly allocated to one of three intervention groups performing RST with varying bout durations and similar repetition volumes, all executed at maximal effort. The 3-sec group (n = 10) completed two sets of 30 bouts, the 6-sec group (n = 10) performed two sets of 15 bouts, and the 9-sec group (n = 10) carried out two sets of 10 bouts, each adhering to a 1:3 work to rest ratio. An active control group (n = 10) engaged solely in regular volleyball training without the RST intervention. Physical fitness measures-including countermovement vertical jump (CMVJ), 10-m and 20-m linear sprints, T-test change-of-direction speed (T-CODS), reactive strength index (RSI), and the Wingate anaerobic power test-were assessed pre- and post-a 6-week training intervention (i.e., 18 sessions). All RST groups showed significant post-intervention improvements in physical fitness (main effect of time, p = 0.001), with greater adaptations compared with the control group and effect sizes ranging from small to very large. The 3-sec bout group demonstrated greater gains in CMVJ, 10-m and 20-m sprint performance, RSI, and peak power output compared with the 9-sec group (all, p < 0.05). Conversely, the 9-sec group exhibited superior adaptations in T-CODS and mean power output relative to the 3-sec group (all, p < 0.05). In conclusion, the 3-sec group experienced greater enhancements in explosive and sprint performances, while the 9-sec group showed superior gains in change of direction and mean power output. These findings indicate that manipulation of sprint-bout duration in RST can be used to optimize distinct performance adaptations in young volleyball players.

Humans

Integrated Multi-omics Profiling of 2,4-dinitrochlorobenzene (DNCB)-induced Atopic Dermatitis in Mice Reveals a Coordinated Network of Barrier Dysfunction, Immune Activation, and Metabolic Reprogramming.

Atopic dermatitis (AD) is caused by a combination of epidermal barrier defect and immune imbalance. However, the molecular networks between these structural abnormalities and metabolic variations are unclear. This study aim of this research was to examine the concurrent molecular alterations in skin barrier damage and metabolic disorders in an AD-like mouse model by a multi-omics strategy. A 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model was established and the skin tissues were examined through the combination of transcriptomic, quantitative proteomic, and metabolomic analyses. Cross-omics correlation and network analyses were performed to identify consistently abnormal molecular pathways and crucial regulatory molecules. DNCB treatment caused severe epidermal hyperplasia, and prominent infiltration of CD3&#x207a; T cells, F4/80&#x207a; macrophages, and mast cells. Transcriptomic and proteomic analysis indicated significant disruption in keratinocyte differentiation, extracellular matrix organization, and cornified envelope formation pathways. Combined analysis detected 171 molecules which were simultaneously altered at both mRNA and protein levels, and network analysis identified FLG2 and KRT6B as central barrier-related molecules. Pathway enrichment analysis consistently showed the participation of AMPK and PPAR signaling pathways. Metabolomic analysis also revealed coordinated changes in lipid and amino acid metabolism which were closely associated with cornified envelope-associated genes and collagen-modifying enzymes. These findings indicate a close relationship between barrier, immune and metabolic regulation in DNCB-induced dermatitis and provide a multi-omics resource for future mechanistic studies of atopic skin inflammation.

Animals

Bidirectional causal relationships between plasma proteins, neuroimaging metrics and risk of Alzheimer's disease.

BACKGROUND: Changes in neuroimaging metrics are among the first detectable pathophysiological alterations in Alzheimer's disease (AD). Proteins are closely linked to fluctuations in neuroimaging metrics. Therefore, the analysis of the proteomic signature associated with neuroimaging metrics holds significant promise for uncovering therapeutic targets that contribute to AD. METHODS: GWAS data concerning the Brain Imaging Data Structure (BIDs). The AD cohort comprised a total of 401,661 individuals diagnosed with AD, alongside 10,520 control participants. For a bidirectional MR analysis involving neuroimaging metrics, proteomics, and AD, the methods utilized included inverse variance weighted (IVW), MR Egger, weighted median, weighted mode, and the Wald ratio approaches. RESULTS: We identified 12 neuroimaging metrics that demonstrate significant relevance to AD (thickness of the left total hemisphere, volume of the right thalamus, and et al.). These metrics are structural magnetic resonance imaging (MRI) biomarkers that remain stable throughout the entire course of AD, from the preclinical stage through mild cognitive impairment (MCI) to dementia. Additionally, we found a substantial number of 1633 proteins that also show a noteworthy causal relationship with AD. Functional enrichment analysis indicated that these proteins were predominantly focused within various pathways linked to AD, encompassing those involved in the synaptic vesicle cycle, synaptic membranes, neurotransmitter release, and the activity of GABA receptors. In addition, our research indicates that the significant relationships observed between the identified proteins and AD are influenced by neuroimaging metrics. Notably, we found that these neuroimaging metrics play a crucial role in mediating a substantial 67% of the inverse relationship that exists between PTPRC and the phenotypic characteristics associated with AD. CONCLUSIONS: This study successfully establishes a connection between proteomic and neuroimaging metrics, as well as the AD that influence them. By creating this relationship, the research offers important information that aids in comprehending the intricate mechanisms involved in AD.

Alzheimer Disease

Metabolome-based genome-wide association study provides genetic insights into the andrographolide accumulation in Andrographis paniculata.

Andrographis paniculata is a distinctive medicinal plant that produces andrographolide-related metabolites, a class of diterpenoid compounds with potent anti-inflammatory activities. To elucidate the genetic mechanisms underlying the biosynthesis of these compounds, we perform comprehensive metabolic profiling and whole-genome resequencing on a natural population of A. paniculata. Population structure analysis reveals four distinct subgroups characterized by low intra-group genetic diversity but significant inter-group differentiation. Through metabolome-based genome-wide association study, we identify a significant locus associated with 14-deoxyandrographolide content. This locus harbors the candidate gene ApNB-ARC25 (CXN00004106), which encodes an NB-ARC domain-containing resistance protein. Functional characterization using virus-induced gene silencing shows that silencing of ApNB-ARC25 significantly reduces andrographolide accumulation and downregulates expressions of key genes in the andrographolide biosynthetic pathway. Heterologous overexpression of ApNB-ARC25 in rice not only improves resistance to blast disease but also enhances diterpenoid phytoalexin production. Our findings reveal that ApNB-ARC25 promotes diterpenoid accumulation and andrographolide biosynthesis by upregulating key genes involved in terpenoid backbone formation and diterpenoid synthesis. This work not only expands the functional understanding of the ApNB-ARC gene family but also provides a genetic resource for enhancing valuable compound accumulation in medicinal plants, offering important insights into the molecular regulation of medicinal metabolite biosynthesis.

Diterpenes

ALDOC and PGK1 coordinately induce glucose metabolism reprogramming and promote development of colorectal cancer.

Colorectal cancer (CRC) remains a significant health challenge globally, demanding a comprehensive understanding of its molecular underpinnings for effective management. In this study, we investigated the role of Aldolase C (ALDOC), a glycolytic enzyme, in CRC pathogenesis. Transcriptomic analysis of CRC tissues from The Cancer Genome Atlas (TCGA) revealed a substantial upregulation of ALDOC, correlating with adverse clinical outcomes. Immunohistochemical (IHC) staining of locally collected patient-derived tissues corroborated these findings, demonstrating elevated ALDOC expression in tumor tissues, particularly in advanced stages. Functional studies elucidated the regulatory role of ALDOC in CRC cell phenotypes. ALDOC knockdown significantly inhibited cell proliferation, induced apoptosis, arrested cell cycle progression, and suppressed cell migration in vitro. Moreover, in vivo studies using xenograft models confirmed that ALDOC knockdown attenuated tumor growth. Mechanistically, ALDOC was found to interact with hypoxia-inducible factor 1 alpha (HIF1A) and enhance its transcriptional activity on phosphoglycerate kinase 1 (PGK1), a key glycolytic enzyme. Dual-luciferase reporter assays and chromatin immunoprecipitation experiments validated the ALDOC-mediated transcriptional activation of PGK1. Further functional rescue experiments revealed a synergistic interplay between ALDOC and PGK1 in regulating CRC cell phenotypes. Additionally, ALDOC was implicated in promoting aerobic glycolysis in CRC cells, potentially through PGK1 regulation. Collectively, our findings unveil ALDOC as a critical regulator of CRC pathogenesis, offering insights into its potential as a therapeutic target and highlighting the ALDOC/PGK1 axis as a promising avenue for further investigation in CRC.

Humans

Comprehensive discovery and functional characterization of the noncanonical proteome.

The systematic identification and functional characterization of noncanonical translation products, such as novel peptides, will facilitate the understanding of the human genome and provide new insights into cell biology. Here, we constructed a high-coverage peptide sequencing reference library with 11,668,944 open reading frames and employed an ultrafiltration tandem mass spectrometry assay to identify novel peptides. Through these methods, we discovered 8945 previously unannotated peptides from normal gastric tissues, gastric cancer tissues and cell lines, nearly half of which were derived from noncoding RNAs. Moreover, our CRISPR screening revealed that 1161 peptides are involved in tumor cell proliferation. The presence and physiological function of a subset of these peptides, selected based on screening scores, amino acid length, and various indicators, were verified through Flag-knockin and multiple other methods. To further characterize the potential regulatory mechanisms involved, we constructed a framework based on artificial intelligence structure prediction and peptide&#x2012;protein interaction network analysis for the top 100 candidates and revealed that these cancer-related peptides have diverse subcellular locations and participate in organelle-specific processes. Further investigation verified the interacting partners of pep1-nc-OLMALINC, pep5-nc-TRHDE-AS1, pep-nc-ZNF436-AS1 and pep2-nc-AC027045.3, and the functions of these peptides in mitochondrial complex assembly, energy metabolism, and cholesterol metabolism, respectively. We showed that pep5-nc-TRHDE-AS1 and pep2-nc-AC027045.3 had substantial impacts on tumor growth in xenograft models. Furthermore, the dysregulation of these four peptides is closely correlated with clinical prognosis. Taken together, our study provides a comprehensive characterization of the noncanonical proteome, and highlights critical roles of these previously unannotated peptides in cancer biology.

Humans

Impact of effluent parameters and vancomycin concentration on vancomycin resistant Escherichia coli and its host specific bacteriophage lytic activity in hospital effluent.

Vancomycin resistance in bacteria has been classified under high priority category by World Health Organization (WHO) and its presence in hospital effluent is reported to be increasing owing to excess antibiotics use. Among various strategies, bacteriophage has been recently considered as a promising biological agent for combating such antimicrobial resistant bacteria (ARB). However, the influence of effluent's properties on phage-ARB interaction in actual hospital effluent is not completely understood. The present works intends to study this influence of hospital effluent and its parameters on the interaction between vancomycin resistant E. coli (VRE) and its host specific bacteriophage. The isolated VRE was identified by 16S rRNA sequencing, matrix-assisted laser desorption/ionization-time of flight (MALDI - TOF) and whole genome sequencing. The infectivity of phage onto host bacteria was investigated using electron microscopic techniques, dynamic light scattering (DLS), spectrofluorophotometer and confirmed using double agar overlay method. The monovalency and polyvalency of isolated phage against various bacterial species were determined. The phage morphology was identical to T7 phage belonging to Podoviridae. The phage lysis was maximum at pH 7 (90.2%), 37&#xa0;&#xb0;C (91.6%) and vancomycin concentration of 50&#xa0;&#x3bc;g/mL in both synthetic media (89.13%) and effluent (100%). At a maximum vancomycin concentration of 100&#xa0;&#x3bc;g/mL, decrease in Ca, K, Mg and P (up to 19.70, 14.18, 28, and 15.82% respectively) concentration in effluent was observed due to phage infectivity when compared to control. The whole genome sequencing was performed and the bioinformatics analysis presented the role of mdfA gene encoding the efflux pump in causing vancomycin resistance in E. coli. It also depicted the presence of multiple genes responsible for mercury, cobalt, zinc and cadmium resistance in VRE. These results clearly indicate that bacteriophage mediated combating of VRE is possible in actual hospital effluent and can be used as one of the treatment methods.

Vancomycin