BackgroundNod-like receptor protein 3 (NLRP3) inflammasome is a crucial factor in mediating inflammatory responses after cerebral ischemia/reperfusion (I/R), but the cellular location of NLRP3 inflammasome in cerebral I/R has yet come to a conclusion, and there is still no specific evidence to state the relationship between mitochondria and the NLRP3 inflammasome in cerebral I/R.MethodsIn the present study, we detected the cellular localization of NLRP3 inflammasomes in a transient middle cerebral artery occlusion (tMCAO) rat model and a transwell co-culture cell system under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions. Then, we investigated the relationship between mitochondrial dysfunction and the activation of NLRP3 inflammasomes in different cell types after OGD/R and cerebral I/R injury.ResultsOur results showed that NLRP3 inflammasomes were first activated in microglia soon after cerebral I/R injury onset and then were expressed in neurons and microvascular endothelial cells later, but they were mainly in neurons. Furthermore, mitochondrial dysfunction played an important role in activating NLRP3 inflammasomes in microglia after OGD/R, and mitochondrial protector could inhibit the activation of NLRP3 inflammasomes in cerebral I/R rats.ConclusionOur findings may provide novel insights into the cell type-dependent activation of NLRP3 inflammasomes at different stages of cerebral I/R injury and the role of mitochondrial dysfunction in activating the NLRP3 inflammasome pathway.Electronic supplementary materialThe online version of this article (10.1186/s12974-018-1282-6) contains supplementary material, which is available to authorized users.

Purpose The purpose of this meta-analysis was to compare platelet-rich plasma (PRP) and hyaluronic acid (HA) in patients with knee osteoarthritis (KOA). Methods Randomized controlled trials (RCTs) comparing the use of PRP and HA in KOA patients were retrieved from each database from the establishment date to April 2018. Outcome measurements were the Western Ontario and McMaster Universities Arthritis Index (WOMAC), visual analog scale (VAS), International Knee Documentation Committee, and Lequesne Index scores and adverse events. The pooled data were evaluated with Review Manager 5.3.5. Results Fifteen RCTs (N = 1,314) were included in our meta-analysis. The present meta-analysis indicated that PRP injections reduced pain more effectively than HA injections in patients with KOA at six and 12 months of follow-up, as evaluated by the WOMAC pain score; the VAS pain score showed a significant difference at 12 months. Moreover, better functional improvement was observed in the PRP group, as demonstrated by the WOMAC function score at three, six, and 12 months. Additionally, PRP injections did not display different adverse event rates compared with HA injections. Conclusion In terms of long-term pain relief and functional improvement, PRP injections might be more effective than HA injections as a treatment for KOA. The optimal dosage, the timing interval and frequency of injections, and the ideal treatment for different stages of KOA remain areas of concern for future investigations.

Background: Retear after arthroscopic rotator cuff repair (ARCR) consistently challenges medical staff and patients, and the incidence of retear after surgery is 10%-94%. The purpose of this study was to identify the risk factors that cause retear after ARCR and provide theoretical guidance for clinical intervention to reduce the occurrence of postoperative rotator cuff retear. Methods: The protocol for this meta-analysis was registered with PROSPERO (CRD42021225088). PubMed, Web of Science, and Embase were searched for observational studies on risk factors for rotator cuff retear after arthroscopic repair. Meta-analytical methods were used to determine the odds ratio or weighted mean difference of potential risk factors related to postoperative rotator cuff retear. Stata 15.1 was used to quantitatively evaluate the publication bias of the statistical results. Results: Fourteen studies from 6 countries with a total of 5693 patients were included. The meta-analysis revealed that the risk factors for retear after rotator cuff repair were age, body mass index, diabetes, subscapularis and infraspinatus fatty infiltration, symptom duration, bone mineral density, tear length, tear width, tear size area, amount of retraction, critical shoulder angle, acromiohumeral interval, distance from the musculotendinous junction to the glenoid, operative duration, biceps procedure, and postoperative University of California Los Angeles shoulder score. Conclusion: These findings can help clinical medical staff identify patients who are prone to retear early after arthroscopic repair and develop targeted prevention and treatment strategies for modifiable risk factors, which are of great significance for reducing the occurrence of rotator cuff retear after ARCR.

The successful reduction of postoperative discomfort is of great significance. This review aims to evaluate the efficacy of low-level laser therapy (LLLT) for the reduction of complication caused by impacted mandibular third molars extraction. An extensive literature search up to October 2013 for randomized controlled trials (RCTs) was performed through CENTRAL, PubMed, Embase, Medline, and CNKI. Six RCTs in which involves 193 participants are included in the meta-analysis. Among them, three RCTs exhibit a moderate risk of bias, while the other three show a high bias risk. Compared with placebo laser/control group, pain is significantly reduced with LLLT on the first day (mean difference [MD] = -2.63, 95% confidence interval [CI] -4.46 to -0.79, P = 0.005). The superiority of LLLT in pain control persists on the second day (MD = -2.34, 95% CI -4.61 to -0.06, P = 0.04) and the third day (MD = -3.40, 95% CI -4.12 to -2.68, P < 0.00001). Moreover, LLLT reduces an average of 4.94 mm (MD = 4.94, 95 % CI 1.53 to 8.34, P = 0.004) of trismus compared with placebo laser irradiation in the first 3 days. On the seventh day, the superiority of LLLT also persists (MD = 3.24, 95% CI 0.37 to 6.12, P = 0.03). In the first 3 days after surgery, extraoral irradiation (MD = -0.69, 95% CI -1.30 to -0.08, P = 0.03) and intraoral combined with extraoral irradiation (MD = -0.65, 95% CI -1.15 to -0.15, P = 0.01) reduced facial swelling significantly. On the seventh day, the intraoral combined with extraoral irradiation group (MD = -0.32, 95% CI -0.59 to -0.06, P = 0.02) still showed benefit in relieving facial swelling. However, because of the heterogeneity of intervention and outcomes assessment and risk of bias of included trials, the efficacy is proved with limited evidence. In the future, well-designed RCTs with larger sample size will be required to provide clearer recommendations.