Biomedical subjects

Bo Xiao

Publications and source records attributed to Bo Xiao.

4 recordsLinked to original sources

PubMed2026

Catalytic Enantioselective Addition of Aryl, Heteroaryl, and Alkenyl Halides to Aliphatic Aldehydes.

Cobalt complexes of chiral Josiphos catalyzed enantioselective addition of aryl, heteroaryl, and alkenyl halides to a wide range of linear and branched aliphatic aldehydes, without using directing groups. The new method was easily scalable with low loadings of cobalt catalysts, and its synthetic utility was demonstrated in concise synthesis of chiral carbinols that are key motifs of drugs or synthetic precursors. The cobalt catalyst also provided high diastereoselectivity in the addition of chiral amino aldehydes. Mechanistic studies suggest cationic complexes of aryl-cobalt(II) act as active species for asymmetric insertion. Lewis acidic titanium alkoxides assist ionization of aryl-cobalt halides to form cationic complexes. The lowest-energy transition states for insertion are stabilized by π-π stacking between the migrating aryl ring and P-phenyl ring of Josiphos.

aldehydes↗

PubMed2026

Genome-wide characterization of NOD-like receptor genes links NLR repertoire evolution to spleen immune responses after Aeromonas hydrophila challenge in the Chinese spiny frog (Quasipaa spinosa).

NOD-like receptors (NLRs) are cytosolic pattern-recognition receptors that detect pathogen-associated and damage-associated molecular patterns and mediate innate immune signaling in vertebrates. However, the genomic repertoire, evolutionary diversification, and infection-associated expression of NLR genes remain poorly defined in non-model amphibians. In this study, 66 NLR genes were identified from the Chinese spiny frog (Quasipaa spinosa) genome and designated as QsNLR1-QsNLR66. These genes were unevenly distributed across chromosomes and were classified into three phylogenetic groups, with most members exhibiting conserved motif architectures. Gene duplication analysis indicated that dispersed duplication was the main contributor to QsNLR expansion. Synteny analysis detected five conserved orthologous gene pairs between Q. spinosa and Pelophylax nigromaculatus, suggesting partial conservation of NLR genomic organization between the two amphibians. Ka/Ks analysis showed that several duplicated gene pairs, including NLRC3-like/QsNLR36 and NLRC3-like/QsNLR50, exhibited Ka/Ks ratios greater than one, suggesting potential sequence divergence after duplication. Spleen RNA sequencing (RNA-seq) after Aeromonas hydrophila challenge revealed enrichment of immune-related Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Weighted gene co-expression network analysis linked several QsNLRs to infection-associated modules, among which QsNLR57 was co-expressed with CYBB, ADAM17, SPI1, and HK2. RT-qPCR using time-matched phosphate-buffered saline (PBS) controls showed distinct temporal patterns, with stronger induction of QsNLR29, QsNLR57, and QsNLR66 and weaker or delayed responses of QsNLR50 and QsNLR56. These results characterize the NLR repertoire of Q. spinosa and identify infection-associated QsNLR candidates for future studies of antibacterial immunity in amphibians.

Animals↗

PubMed2025

The impact of m6A methyltransferase METTL3 on airway remodeling in bronchial asthma.

BACKGROUND: Methyltransferase-like 3 (METTL3) is known to play a role in asthma airway remodeling and cell proliferation. Adenylate kinase 4 (AK4) regulates the proliferation of pulmonary artery smooth muscle cells and exerts its effects through the protein kinase B (AKT) pathway. However, the role of METTL3 and AK4-AKT in bronchial smooth muscle cells remains unclear. METHODS: Systemic METTL3 knockout mice and a mouse model of asthma were established. Airway remodeling was assessed using pulmonary function tests, histopathological staining, and Western blot analysis. RNA sequencing (RNA-seq) was performed to detect changes in gene expression following METTL3 knockdown. The 5-ethynyl-2'-deoxyuridine (EdU) assay was used to evaluate cell proliferation. Finally, the expression levels of relevant proteins were validated by Western blotting. RESULTS: Compared with the control model group, the METTL3 knockout group showed significantly reduced inflammatory cell infiltration, decreased collagen fiber deposition, and attenuated airway smooth muscle hyperplasia. RNA-seq revealed that the expression of numerous proliferation-related genes, including AK4, was upregulated following METTL3 knockdown. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that these genes were primarily enriched in the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway. The EdU assay demonstrated that METTL3 knockdown inhibited cell proliferation. Western blot validation showed increased AK4 expression in lung tissues of the METTL3 knockout group compared to the control group, while phosphorylated AKT (p-AKT) levels were reduced. CONCLUSIONS: METTL3 knockout inhibits airway smooth muscle hyperplasia and alleviates airway remodeling in asthma. This effect may be mediated through the regulation of AK4 and the AKT signaling pathway.

Airway Remodeling↗

PubMed2024

Causal effects of sedentary behaviours on the risk of migraine: A univariable and multivariable Mendelian randomization study.

BACKGROUND: Migraine is a common and burdensome neurological disorder. The causal relationship between sedentary behaviours (SBs) and migraine remains instinct. We aimed to evaluate the roles of SBs including watching TV, using computer and driving in the risk of migraine. METHODS: We conducted a univariable and multivariable Mendelian randomization (MR) study based on summary datasets of large genome-wide association studies. The inverse variance weighted method was utilized as the primary analytical tool. Cochran's Q, MR-Egger intercept test, MR pleiotropy residual sum and outlier and leave-one-out were conducted as sensitivity analysis. Additionally, we performed a meta-analysis to combine the causal estimates. RESULTS: In the discovery analysis, we identified causal associations between time spent watching TV and an increased risk of migraine (p = 0.015) and migraine without aura (MO) (p = 0.002). Such causalities with increasing risk of migraine (p = 0.005), and MO (p = 0.006) were further verified using summary datasets from another study in the replication analysis. There was no significant causal association found between time spent using computer, driving and migraine or its two subtypes. The meta-analysis and multivariable MR analysis also strongly supported the causal relationships between time spent watching TV and an increased risk of migraine (p = 0.0003 and p = 0.034), as well as MO (p < 0.0001 and p = 0.0004), respectively. These findings were robust under all sensitivity analysis. CONCLUSIONS: Our study suggested that time spent watching TV may be causally associated with an increased risk of migraine, particularly MO. Large-scale and well-designed cohort studies may be warranted for further validation. SIGNIFICANCE STATEMENT: This study represents the first attempt to investigate whether a causal relationship exists between SBs and migraine. Utilizing MR analysis helps mitigate reverse causation bias and confounding factors commonly encountered in observational cohorts, thereby enhancing the robustness of derived causal associations. Our MR analysis revealed that time spent watching TV may serve as a potential risk factor for migraine, particularly MO.

Humans↗