Three-gene signature revealing the dynamics of lymphocyte infiltration in subchondral bone during osteoarthritis progression.

Osteoarthritis (OA), a degenerative joint disorder, has an unclear immune infiltration mechanism in subchondral bone (SCB). Thus, this study aims to discern immune infiltration variations in SCB between early- and late-stages of OA and identify pertinent biomarkers. Utilizing the GSE515188 bulk-seq profile from the Gene Expression Omnibus database, we performed single-sample gene-set enrichment analysis alongside weighted gene co-expression network analysis to identify key cells and immune-related genes (IRGs) involved in SCB at both stages. At the meanwhile, differentially expressed genes (DEGs) were identified in the same dataset and intersected with IRGs to find IR-DEGs. Protein-protein interaction network and enrichment analyses and further gene filtering using LASSO regression led to the discovery of potential biomarkers, which were then validated by ROC curve analysis, single-cell RNA sequencing, qRT-PCR, western blot and immunofluorescence. ScRNA-seq analysis using GSE196678, qRT-PCR, western blot and immunofluorescence results confirmed the upregulation of their expression levels in early-stage OA SCB samples. Our comprehensive analysis revealed lymphocytes infiltration as a major feature in early OA SCB. A total of 13 IR-DEGs were identified, showing significant enrichment in T- or B-cell activation pathways. Three of them (CD247, POU2AF1, and TNFRSF13B) were selected via the LASSO regression analysis, and results from the ROC curve analyses indicated the diagnostic efficacy of these 3 genes as biomarkers. These findings may aid in investigating the mechanisms of SCB immune infiltration in OA, stratifying OA progression, and identifying relevant therapeutic targets.

Detection of right to left shunt by transesophageal echocardiography in a patient with postoperative hypoxemia.

Intracardiac right to left shunt through a patent foramen ovale (PFO) may result in the development of hypoxemia after cardiac surgery. Cardiac tamponade and mechanical ventilation with high positive endexpiratory pressure are the most common factors responsible for enhancing intracardiac right to left shunt through a PFO. We report an 83-year-old woman with Stanford type A dissecting aneurysm who developed hypoxemia and paradoxical air embolism after reconstruction of ascending aorta and Bental's procedure. Transesophageal echocardiography (TEE) revealed right to left shunting via a PFO. Surgical closure of the PFO was done without delay. This case illustrates the role of TEE in prompt diagnosis of intracardiac right to left shunting through a PFO causing postoperative hypoxemia after cardiac surgery.

Delayed recovery of radial nerve function after axillary block in a patient receiving ipsilateral ulnar nerve transposition surgery.

A 68-year-old female who underwent right ulnar nerve transposition surgery under axillary block (AB) by dual-technique (paresthesia and axillary artery penetration techniques) developed postoperative wristdrop. Physical examination showed local hematoma formation with ecchymosis at her right axillary region. Both ultrasonography and nerve conduction studies on her brachial plexus revealed neither direct hematoma compression, intraneural hematoma, nor peripheral neuropathy. Fortunately, she was completely restored to her right hand function 20 h after anesthesia, and was discharged without sequelae 17 days later. In this case, delayed recovery of radial nerve function after AB was suspected and the mechanism which led to this unusualness is discussed.