Efficacy of percutaneous cement-augmented screw fixation plus percutaneous kyphoplasty in the management of unstable osteoporotic vertebral compression fractures.

OBJECTIVE: The present study was performed to compare the efficacy of percutaneous kyphoplasty (PKP) vs. percutaneous cement-augmented screw fixation plus PKP in the management of unstable osteoporotic vertebral compression fractures (OVCF). PATIENTS AND METHODS: A total of 197 patients with unstable OVCF treated in the Department of Spine Surgery, Lianyungang First People's Hospital from September 2019 to September 2021 were recruited and assigned via random number table method 1:1 to receive either PKP (group A, n=106) or PKP plus percutaneous cement-augmented screw fixation (group B, n=91). The outcome measures for the evaluation of different surgical methods included visual analogue scale (VAS), the height of the anterior-posterior border of the injured spine, Cobb angle of the posterior convexity, Oswestry disability index (ODI) scores, and Japanese Orthopaedic Association (JOA) scores. RESULTS: PKP exhibited shorter operative time and length of hospital stay and less intraoperative blood loss vs. PKP plus percutaneous cement-augmented screw fixation (p<0.05). Patients with PKP plus percutaneous cement-augmented screw fixation experienced milder postoperative pain vs. those with PKP alone at 7 days postoperatively, as evidenced by the lower VAS scores (p<0.05). PKP plus percutaneous cement-augmented screw fixation provided more restoration of anterior margin height and posterior convexity Cobb angle vs. PKP alone (p<0.05). Patients with PKP only showed slightly higher Japanese Orthopaedic Association (JOA) scores than those with combined surgery, while the postoperative clinical signs between the two arms were similar (p>0.05). CONCLUSIONS: Single PKP features the benefits of minimal trauma, simple operation, and rapid postoperative recovery in the treatment of OVCF. PKP plus percutaneous cement-augmented screw fixation for severe OVCF provided distinctly better performance than PKP alone in terms of early pain relief, restoration of vertebral body height, correction of posterior convexity deformity, and firm spinal stability.

Injected cells provide a valuable complement to cell-free systems for analysis of gene expression.

The aim of this short review is to comment on the advantages of injecting purified molecules into a normal living cell as a complement to the constitution of a cell-free system for analyzing the function of cell components. We emphasize here that the major difference is that, by injection, most components of a cell are maintained at their normal concentration, which is difficult, even if at all possible, to achieve in a cell-free system. We exemplify the benefits of a cell injection system by the efficiency and long duration of DNA transcription by RNA polymerase II, as used by most genes, and by the widespread success of injecting purified messenger RNA for protein synthesis. The most recent work using cell injection also gives a new understanding of a long lasting transcription factor residence on its DNA or chromatin not shown by other procedures. Lastly, we re-visit an old idea that transcription factors that guide cell fate may be stably bound to DNA or chromatin, except at S-phase or mitosis in the cell cycle, when they can undergo exchange with equivalent molecules in the cell.

Ligands of macrophage scavenger receptor induce cytokine expression via differential modulation of protein kinase signaling pathways.

Our previous works demonstrated that ligands of macrophage scavenger receptor (MSR) induce protein kinases (PKs) including protein-tyrosine kinase (PTK) and up-regulate urokinase-type plasminogen activator expression (Hsu, H. Y., Hajjar, D. P., Khan, K. M., and Falcone, D. J. (1998) J. Biol. Chem. 273, 1240--1246). To continue to investigate MSR ligand-mediated signal transductions, we focus on ligands, oxidized low density lipoprotein (OxLDL), and fucoidan induction of the cytokines tumor necrosis factor-alpha (TNF) and interleukin 1 beta (IL-1). In brief, in murine macrophages J774A.1, OxLDL and fucoidan up-regulate TNF production; additionally, fucoidan but not OxLDL induces IL-1 secretion, prointerleukin 1 (proIL-1, precursor of IL-1) protein, and proIL-1 message. Simultaneously, fucoidan stimulates activity of interleukin 1-converting enzyme. We further investigate the molecular mechanism by which ligand binding-induced PK-mediated mitogen-activated protein kinase (MAPK) in regulation of expression of proIL-1 and IL-1. Specifically, fucoidan stimulates activity of p21-activated kinase (PAK) and of the MAPKs extracellular signal-regulated kinase (ERK), c-Jun NH(2)-terminal kinase (JNK), and p38. Combined with PK inhibitors and genetic mutants of Rac1 and JNK in PK activity assays, Western blotting analyses, and IL-1 enzyme-linked immunosorbent assay, the role of individual PKs in the regulation of proIL-1/IL-1 was extensively dissected. Moreover, tyrosine phosphorylation of pp60Src as well as association between pp60Src and Hsp90 play important roles in fucoidan-induced proIL-1 expression. We are the first to establish two fucoidan-mediated signaling pathways: PTK(Src)/Rac1/PAK/JNK and PTK(Src)/Rac1/PAK/p38, but not PTK/phospholipase C-gamma 1/PKC/MEK1/ERK, playing critical roles in proIL-1/IL-1 regulation. Our current results indicate and suggest a model for MSR ligands differentially modulating specific PK signal transduction pathways, which regulate atherogenesis-related inflammatory cytokines TNF and IL-1.