Synovial fluid research based on SERS and SERRS for enhanced detection of biomarkers in staged osteoarthritis.

Surface-enhanced (resonance) Raman scattering (SER(R)S) can extremely enhance Raman intensity of samples, which is helpful for detecting synovial fluid (SF) that does not show Raman activity under normal conditions. In this study, SER(R)S spectra of SF from three different osteoarthritis (OA) stages were collected and analyzed for OA progress, finding that the content of collagen increased throughout the disease, while non-collagen proteins and polysaccharides decreased sharply at advanced OA stage accompanied by the increase of phospholipid. The spectral features and differences were enhanced by salting-out and centrifugation. Much more information on biomolecules at different OA stages was disclosed by using SERRS for the first time, these main trace components (ß-carotene, collagen, hyaluronic acid, nucleotide, and phospholipid) can be used as potential biomarkers. It indicates that SERRS has a more comprehensive ability to assist SERS in seeking micro(trace) biomolecules as biomarkers and facilitating accurate and efficient diagnosis and mechanism research of OA.

LncRNA TSIX aggravates spinal cord injury by regulating the PI3K/AKT pathway via the miR-532-3p/DDOST axis.

Long noncoding RNA (lncRNA)-X-inactive-specific transcript (TSIX) expression is upregulated in spinal cord tissues following spinal cord injury (SCI). However, the role of lncRNA-TSIX in SCI remains elusive. SCI animal model was established using C57BL/6 mice. LncRNA TSIX and miR-532-3p expression were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Apoptosis, cell proliferation, and migration were evaluated by transferase dUTP nick end labeling staining, CCK-8, and Transwell assays, respectively. The interaction of miR-532-3p with lncRNA TSIX and DDOST was explored via a dual-luciferase reporter system. Hematoxylin-eosin staining and the Basso, Beattie, and Bresnahan locomotor rating (BBB) scale were performed to investigate SCI progression. The expression of the lncRNA TSIX was found to be significantly upregulated in the serum of SCI patients and spinal cord tissues of SCI mice. The overexpression of lncRNA TSIX enhanced spinal cord neural stem cell (SC-NSC) proliferation and migration in vitro while inhibiting apoptosis and inflammatory cell infiltration in vivo. Moreover, lncRNA TSIX acted as a molecular sponge for miR-532-3p, and the knockdown of miR-532-3p promoted proliferation and migration and inhibited apoptosis of SC-NSCs. Moreover, DDOST was found to be the downstream target of miR-532-3p, and DDOST overexpression showed a similar effect as miR-532-3p silencing on the proliferation, migration, and apoptosis of SC-NSCs. Furthermore, we found that lncRNA TSIX overexpression promoted the activation of the PI3K/AKT signaling pathway. LncRNA TSIX aggravates SCI by regulating the PI3K/AKT pathway via the miR-532-3p/DDOST axis, indicating potential applications for targeted therapy of SCI regeneration.

Adjustable-Loop Cortical Button Fixation Results in Good Clinical Outcomes for Acute Tibial Avulsion Fracture of the Posterior Cruciate Ligament.

Purpose: To evaluate the clinical outcomes for arthroscopic treatment of acute posterior cruciate ligament (PCL) avulsion fractures with adjustable-loop cortical button fixation device. Methods: Patients with PCL tibial avulsion fractures treated with an adjustable-loop cortical button fixation device between October 2019 and October 2020 were retrospectively identified. Patients with type 1 were treated using plaster fixation as a conservative treatment, whereas patients with type 2 and 3 with displacement were treated using an arthroscopic adjustable-loop cortical button. Operating time, incision recovery, complications, and postoperative fracture healing time were monitored. All patient follow-up was done at 12 months' postoperatively. Lysholm Knee Score and the International Knee Documentation Committee score were used to assess knee function. Results: A total of 30 patients were included in the study (20 male/10 female; mean age 45.5 years, range 35-68 years). The mean operative time was 67.5 minutes (range: 50-90 minutes). The postoperative incision healed at stage A without complications, such as medically induced vascular nerve injury, intra-articular hematoma, or infection. All 30 patients were tracked postoperatively for 12 to 14 months, with a mean follow-up period of 12.6 months. The Lysholm knee function score was 45.93 ± 6.15 before surgery and 87.10 ± 3.71 at 12 months after surgery, and the International Knee Documentation Committee score was 19.27 ± 4.40 before surgery and 95.47 ± 1.87 at 12 months after surgery, with a statistically significant difference. Conclusions: The treatment of PCL avulsion fractures with arthroscopic adjustable-loop cortical button fixation is easy to perform and shows good clinical results in our study. Level of Evidence: IV, therapeutic case series.

Inhibitory effects of platelet-rich plasma on intervertebral disc degeneration: a preclinical study in a rabbit model.

BACKGROUND: Platelet-rich plasma (PRP) contains multiple growth hormones that may stimulate tissue repair. This study aimed to assess the effects of PRP in a rabbit model of IDD (annulus fibrosus puncture). MATERIAL/METHODS: Thirty-six adult New Zealand white rabbits were randomly divided into 3 groups: 0.1 mL PRP (group A), 0.1 mL phosphate-buffered saline (group B), and control (group C) (n=12/group). Annulus fibrosus puncture was performed to establish L4/5 and L5/6 IDD models. Two and 4 weeks later, 6 rabbits from each group were given an IVD injection at L4/5 and L5/6. Two or 4 weeks after injection, rabbits were scanned with X-ray and MRI before being sacrificed. IVDs were collected for hematoxylin and eosin, Masson's trichrome, and Safranin O staining, and type II collagen immunohistochemistry. RESULTS: Over time, IVD height and disc imaging signal intensity decreased gradually in groups B and C, but only slightly in group A (baseline: 100% for all groups; A: 95.9±4.2% at 4 weeks, 90.1±8.4 at 6 weeks; B: 75.3±5.7% at 4 weeks, 70.8±6.4% at 6 weeks; C: 74.7±5.5% at 4 weeks, 69.9±6.2% at 6 weeks; all P<0.001, P<0.01 between A vs. B and C). Degenerative histological changes in IVDs in groups B and C were more severe compared with group A. CONCLUSIONS: Platelet-rich plasma interventions can effectively attenuate the IDD process in rabbits.