Morphological study of CT image of posterior pilon variant fracture and its possible clinical significance.

OBJECTIVE: The incidence of posterior pilon variant fractures has been underestimated. The purpose was to study the characteristics of posteromedial (PM) and posterolateral (PL) fragments in CT imaging of posterior pilon variant fractures, and to provide help for clinical diagnosis and treatment. METHODS: CT imaging data of 109 cases of posterior pilon variant fractures in our hospital from January 2013 to December 2020 were retrospectively analyzed. According to Mason and Molloy classification, PM fragments were further divided into pilon subtypes and avulsed subtypes. The largest actual area of fragments in axial and sagittal were selected as the study plane, and the maximum axial lengths of X, Y and Z, α angle, ß angle, fragment area (S1-7) and fragment area ratio (FAR1-4), interfragmentary (IF) angle, and back of tibia (BT) angle were measured. RESULTS: A total of 109 cases were included in this study, 61 of whom were pilon subtypes [90.16% were supination-external rotation (SER) injuries]. 48 cases were avulsed subtypes [81.25% were pronation-external rotation (PER) injuries]. Pilon subtypes were larger than avulsed subtypes in X, Y, Z, α2 Angle, ß2 Angle, fragment area and ratio, and IF and BT angle (P < 0.05). There was no difference between α1 and ß1 angle (P > 0.05). CONCLUSION: The morphology of pilon subtype was larger than that of avulsion subtype. According to fragment size, morphology, and injury mechanism, two fragments of pilon subtype should be anatomic reduction and fixation. However, the PL fragment of avulsion subtype should to be fixed, while PM fragment may only need conservative treatment.

Long noncoding RNA H19 alleviates inflammation in osteoarthritis through interactions between TP53, IL-38, and IL-36 receptor.

AIMS: Osteoarthritis (OA) is a common degenerative joint disease characterized by chronic inflammatory articular cartilage degradation. Long noncoding RNAs (lncRNAs) have been previously indicated to play an important role in inflammation-related diseases. Herein, the current study set out to explore the involvement of lncRNA H19 in OA. METHODS: Firstly, OA mouse models and interleukin (IL)-1ß-induced mouse chondrocytes were established. Expression patterns of IL-38 were determined in the synovial fluid and cartilage tissues from OA patients. Furthermore, the targeting relationship between lncRNA H19, tumour protein p53 (TP53), and IL-38 was determined by means of dual-luciferase reporter gene, chromatin immunoprecipitation, and RNA immunoprecipitation assays. Subsequent to gain- and loss-of-function assays, the levels of cartilage damage and proinflammatory factors were further detected using safranin O-fast green staining and enzyme-linked immunosorbent assay (ELISA) in vivo, respectively, while chondrocyte apoptosis was measured using Terminal deoxynucleotidyl transferase dUTP Nick-End Labeling (TUNEL) in vitro. RESULTS: IL-38 was highly expressed in lentivirus vector-mediated OA mice. Meanwhile, injection of exogenous IL-38 to OA mice alleviated the cartilage damage, and reduced the levels of proinflammatory factors and chondrocyte apoptosis. TP53 was responsible for lncRNA H19-mediated upregulation of IL-38. Furthermore, it was found that the anti-inflammatory effects of IL-38 were achieved by its binding with the IL-36 receptor (IL-36R). Overexpression of H19 reduced the expression of inflammatory factors and chondrocyte apoptosis, which was abrogated by knockdown of IL-38 or TP53. CONCLUSION: Collectively, our findings evidenced that upregulation of lncRNA H19 attenuates inflammation and ameliorates cartilage damage and chondrocyte apoptosis in OA by upregulating TP53, IL-38, and by activating IL-36R.Cite this article: Bone Joint Res 2022;11(8):594-607.

Fumitremorgin C alleviates advanced glycation end products (AGE)-induced chondrocyte inflammation and collagen II and aggrecan degradation through sirtuin-1 (SIRT1)/nuclear factor (NF)-κB/ mitogen-activated protein kinase (MAPK).

Fumitremorgin C is a potent and selective inhibitor of the breast cancer resistance protein. This study aimed to explore the role of fumitremorgin C in osteoarthritis (OA) and disclose the underlying mechanism. The cell viability of AGE-treated SW1353 cells in the presence of fumitremorgin C was detected by Cell Counting Kit-8 (CCK-8) assay. The inflammation and extracellular matrix (ECM) deposition of AGE-induced SW1353 cells was respectively measured by enzyme linked immunosorbent assay (ELISA), immunofluorescence, and Western blot. The expression of SIRT1 and NF-KB/MAPK signal was examined by Western blot. After that, SIRT1 inhibitor EX527 was added to observe the mechanism of action of fumitremorgin C. Fumitremorgin C restored the cell viability of SW1353 cells injured by AGE. Furthermore, it alleviated inflammation and ECM degradation in AGE-induced SW1353 cell. The SIRT1 expression decreased by AGE was recovered upon fumitremorgin C to SW1353 cells. The ratio of phosphorylated p65 (p-p65) and p65, phosphorylated JNK (p-JNK) and JNK, and phosphorylated 38 (p-38) and 38 were increased by AGE treatment, which was recovered by fumitremorgin C addition. SIRT1 inhibitor EX527 reverts the repressive effects of fumitremorgin C on inflammation and ECM degradation in AGE-induced SW1353 cell. In conclusion, fumitremorgin C alleviates AGE-induced inflammation and the degradation of collagen II and aggrecan through SIRT1/NF-κB/MAPK, which reveals the underlying mechanism by which fumitremorgin C alleviates OA.

Pharmacological Effects of Fasudil on Flap Survival in a Rodent Model.

BACKGROUND: Necrosis of the perforator flap is a critical problem. Fasudil, an inhibitor of Rho-associated coiled-coil containing kinase, has antiapoptosis activity and attenuates oxidative stress in many diseases. We characterized the effects of fasudil through intraperitoneal injection on perforator flap survival and identified its possible mechanism. METHODS AND MATERIALS: Rats were divided into a control group (without surgery), a flap group (only surgery), and a fasudil group (surgery plus fasudil). Perforator flaps were made on the backs of the rats. The expression of vascular endothelial growth factor, the protein kinase B (PKB/Akt), endothelial nitric oxide synthase, Bax, Bcl-2, Beclin-1, P62, and LC3 II/LC3 I was determined by Western blot at day 3 after surgery. Nitric oxide (NO) components, superoxide dismutase, and malondialdehyde were also measured at day 3. The survival rate and laser Doppler perfusion imaging were performed at day 7 after surgery. RESULT: The group with fasudil treatment exhibited the higher survival rates and angiogenesis levels. Fasudil also induced the activation of Akt/eNOS/NO pathway detected by the Western blot and NO expression kit. Furthermore, Western blot results showed fasudil-attenuated apoptosis through a raised Bcl-2/Bax rate and enhanced autophagy levels through raised beclin-1, decreased p62, and the elevated rate of LC3 II/LC3 I. Finally, fasudil increased superoxide dismutase and decreased malondialdehyde. CONCLUSIONS: In conclusion, fasudil treatment decreased necrosis of perforator flaps possibly by affecting the Akt/eNOS/NO pathway, attenuating apoptosis and activating autophagy.

[Incidence and risk factors of early deep venous thrombosis after knee arthroscopy operation under conventional tourniquet].

OBJECTIVE: To find out the incidence of early DVT in patients after knee arthroscopic surgery with routine use of tourniquet and discuss the associate risk factors. METHODS: Total 1 561 cases undertaken primary knee arthroscopic surgery was reviewed retrospectively from January 2013 to January 2017, including 651 males and 910 females with a mean age of (65.7±8.7) years old ranging from 62 to 81 years old. The cases were divided into DVT group and non-DVT group according to ultrasonic Doppler after surgery. The DVT occurrence rate was calculated and the basic information was analyzed to filter out the risk factors through univariate analysis and multivariate analysis. The cases of DVT group received 6 months anticoagulation therapy and were undertaken a follow-up of 1, 3, 6 months by ultrasonic Doppler. RESULTS: Out of the 1 561 cases, 226(14.5%) developed early DVTs following surgery, 32(2.0%) cases had the proximal DVTs, and 194(12.4%) cases had the isolated distal DVTs. The risk factors include the age(>=73 years), female sex and gastrocnemius vein dilation (GVD), hypertension, longer tourniquet time(>=74 min). The GVD and the length of tourniquet time was considered to be the best predictor of the early DVTs after surgery, with an odds ratio of 2.337 (95% CI, 1.644-3.611) and 2.112 (95%CI, 1.452-3.301). Twelve isolated distal DVTs(6.6%) and 11 proximal DVTs(36.7%) still showed thrombus at 6-month follow-up, but exhibit decreased size and at various stage of resolution. CONCLUSIONS: The incidence of early DVTs after knee arthroscopic surgery is 14.5%. Out of all risk factors, the GVD and the length of tourniquet time have the best power for prediction of DVTs after surgery. Both proximal and distal DVTs received accepted outcomes after formal therapy.

Shikonin inhibits myeloid differentiation protein 2 to prevent LPS-induced acute lung injury.

BACKGROUND AND PURPOSE: Acute lung injury (ALI) is a challenging clinical syndrome, which manifests as an acute inflammatory response. Myeloid differentiation protein 2 (MD2) has an important role in mediating LPS-induced inflammation. Currently, there are no effective molecular-based therapies for ALI or viable biomarkers for predicting the severity of disease. Recent preclinical studies have shown that shikonin, a natural naphthoquinone, prevents LPS-induced inflammation. However, little is known about the underlying mechanisms. EXPERIMENTAL APPROACH: The binding affinity of shikonin to MD2 was analysed using computer docking, surface plasmon resonance analysis and elisa. In vitro, the anti-inflammatory effect and mechanism of shikonin were investigated through elisa, real-time quantitative reverse transcription PCR, Western blotting and immunoprecipitation assay. In vivo, lung injury was induced by intratracheal administration of LPS and assessed by changes in the histopathological and inflammatory markers. The underlying mechanisms were investigated by immunoprecipitation in lung tissue. KEY RESULTS: Shikonin directly bound to MD2 and interfered with the activation of toll-like receptor 4 (TLR4) induced by LPS. In cultured macrophages, shikonin inhibited TLR4 signalling and pro-inflammatory cytokine production. These effects were produced through suppression of key signalling proteins including the NF-κB and the MAPK pathway. We also showed that shikonin inhibits MD2-TLR4 complex formation and reduces LPS-induced inflammatory responses in a mouse model of ALI. CONCLUSIONS AND IMPLICATIONS: Our studies have uncovered the mechanism underlying the biological activity of shikonin in ALI and suggest that the targeting of MD2 may prove to be beneficial as a treatment option for this condition.

Targeting myeloid differentiation protein 2 by the new chalcone L2H21 protects LPS-induced acute lung injury.

Acute inflammatory diseases are the leading causes of mortality in intensive care units. Myeloid differentiation 2 (MD-2) is required for recognizing lipopolysaccharide (LPS) by toll-like receptor 4 (TLR4), and represents an attractive therapeutic target for LPS-induced inflammatory diseases. In this study, we report a chalcone derivative, L2H21, as a new MD2 inhibitor, which could inhibit LPS-induced inflammation both in vitro and in vivo. We identify that L2H21 as a direct inhibitor of MD-2 by binding to Arg90 and Tyr102 residues in MD-2 hydrophobic pocket using a series of biochemical experiments, including surface plasmon response, molecular docking and amino acid mutation. L2H21 dose dependently inhibited LPS-induced inflammatory cytokine expression in primary macrophages. In mice with LPS intratracheal instillation, L2H21 significantly decreased LPS-induced pulmonary oedema, pathological changes in lung tissue, protein concentration increase in bronchoalveolar lavage fluid, inflammatory cells infiltration and inflammatory gene expression, accompanied with the decrease in pulmonary TLR4/MD-2 complex. Meanwhile, administration with L2H21 protects mice from LPS-induced mortality at a degree of 100%. Taken together, this study identifies a new MD2 inhibitor L2H21 as a promising candidate for the treatment of acute lung injury (ALI) and sepsis, and validates that inhibition of MD-2 is a potential therapeutic strategy for ALI.

[Clinical research on the efficiency of physical examinations used for diagnosis of subacromial impingement syndrome].

OBJECTIVE: To evaluate the reliability and diagnosis accuracy of 5 special tests used for the diagnosis of subacromial impingement syndrome (SAIS). METHODS: A prospective blinded cohort study was taken,in which 105 patients with shoulder pain were reviewed. All the patients took 5 special syndrome tests including Neer syndrome, Hawkins-Kennedy syndrome, painful arc empty can test and external rotation resistance test, also underwent arthroscopic surgical examination. The Nikolaus's criterion was regarded as a golden standard for SAIS. Data accuracy analysis was calculated through a receiver operating characteristic (ROC) curve, sensitivity, specificity, positive likelihood ratio (+LR) and negative likelihood ratio (-LR). The binary Logistic regression analysis was used to find out the best test combination for ruling in or out SAIS. The interrater reliability was assessed by the Kappa coefficient and percent agreement. RESULTS: The ROC analysis indicated a significant area under the curve (AUC) (AUC=0.62 to 0.73, P<0.05) for all tests except the Hawkins-Kennedy. Tests with a +LR greater or equal to 2.0 were the painful arc,empty can,external rotation resistance, Tests with a-LR less than 0.5 were Neer,painful are ,external rotation resistance. The regression analysis found the painful arc, empty can and external rotation resistance made the best combination for diagnosis SAIS,while the painful are and external rotation resistance made the best combination for ruling out SAIS. The difference of ROC analysis was significant with a cut-off of 3 positive tests out of 5 tests. All tests had moderate to good agreement (Kappa=0.42 to 0.71). CONCLUSION: The single test of painful arc, empty can and external rotation resistance, as well as 3 or more positive tests of the 5 tests can help confirm the diagnosis of SAIS, while the single test of Neer, painful arc and external rotation resistance are help rule out the diagnisis of SAIS. The tests of painful arc, empty can and ex ternal rotation resistance are the best combination for the diagnosis of SAIS (when 2 or more are positive), while the tests of painful arc and external rotation resistance are the best combination for ruling out SAIS (when both are negative)

Synthesis and Cytotoxic Evaluation of Monocarbonyl Analogs of Curcumin as Potential Anti-Tumor Agents.

Preclinical Research A series of mono-carbonyl curcumin analogs with different substituents at the 4/4'-position of the phenyl group were synthesized and screened for in vitro cytotoxicity against a panel of human cancer cell lines using a methyl thiazolyl tetrazolium assay. Several of the curcumin analogs, especially B114, exhibited a wide-spectrum of anti-tumor properties in all tested cell lines, indicating their potential in as anti-cancer lead compounds. Further toxicity testing in the NRK-52E kidney cell line revealed that the analogs A111, A113, and B114 had comparable or higher safety than curcumin. These data suggested that the introduction of appropriate substituents in the 4/4'-positions could be a promising approach for curcumin-based drug design.

[Minimally invasive pie-crusting technique combined with arthrolysis for the treatment of the stiff knee].

OBJECTIVE: To study the effectiveness of pie-crusting technique in improving the stiff knee. METHODS: From February 2012 to December 2013, 13 patients with stiff knee were reviewed retrospectively. There were 6 males and 7 females, ranging in age from 39 to 70 years old (averaged, 55.6 years old). Of the 13 cases, 8 patients had stiffness following fracture (comminuted tibial plateau fracture in 4, femoral supracondylar fracture in 3 and patellar fracture in 1), 5 patients had TKA-related stiffness. RESULTS: A follow-up lasted 8 to 12 months (mean 10 months)in 13 cases. The mean maximum flexion increased from (37 ± 6)° preoperatively to (52 ± 7)° after arthrolysis, and (108 ± 7)° after pie-crusting. At the final follow-up, mean maximum flexion was (105 ± 6)°. According to Judet evaluation system, 10 patients got an excellent result and 3 good. No major complications, such as extensor lag, skin necrosis, deep infection, dislocation of the patella or recurrent stiffness were found. CONCLUSION: The percutaneous technique of pie-crusting is a simple, minimally invasive and effective treatment for knee stiffness.

Discovery and evaluation of novel anti-inflammatory derivatives of natural bioactive curcumin.

Curcumin is a natural active product that has various pharmacological activities such as anti-inflammatory effects. Here, we report the synthesis and evaluation of 34 monocarbonyl curcumin analogs as novel anti-inflammatory agents. Among the analogs, the symmetrical heterocyclic type displayed the strongest inhibition of lipopolysaccharide (LPS)-stimulated expression of pro-inflammatory cytokines in macrophages. Analogs S1-S5 and AS29 reduced tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production in a dose-dependent manner and also displayed excellent stability and low cytotoxicity in vitro. In addition, analog S1 dose-dependently inhibited LPS-induced extracellular signal-regulated kinase (ERK) phosphorylation. Furthermore, analogs S1 and S4 displayed a significant protective effect on LPS-induced septic death in mouse models, with 40% and 50% survival rates, respectively. These data demonstrate that the heterocyclic monocarbonyl curcumin analogs have potential therapeutic effects in acute inflammatory diseases.

Discovery and evaluation of piperid-4-one-containing mono-carbonyl analogs of curcumin as anti-inflammatory agents.

We previously reported the design and discovery of three series of 5-carbon linker-containing mono-carbonyl analogs of curcumin (MCACs) as excellent anti-inflammatory agents. In continuation of our ongoing research, we designed and synthesized the fourth series of MCACs, whose central linker is a piperid-4-one. Their inhibitory effects against IL-6 production were evaluated in lipopolysaccharide (LPS)-stimulated macrophages. Among them, compounds F8, F29, F33, F35, and F36 exhibited the IC50 values under 5 µM. The structure-activity relationship was discussed. Mechanistically, F35 and F36 dose-dependently prevented LPS-induced NF-κB and ERK activation. Finally, pretreatment with F35 and F36 significantly protected the C57B/L6 mice from LPS-induced septic death. Together, these data present a series of new analogs of curcumin as promising anti-inflammatory agents.

[Open reduction and internal fixation via a posterior approach for posterior fractures of tibial plateau].

OBJECTIVE: To discuss the fracture patterns,operative procedures and clinical results of open reduction and internal fixation via a posterior approach to treat posterior fractures of tibial plateau. METHODS: From June 2008 to February 2011, 8 patients with posterior tibial plateau fractures treated with posterior approach, were reviewed retrospectively. There were 5 males and 3 females,with an average of 41.1 years ranging from 23 to 55. Of the 8 cases, 5 cases were caused by traffic accidents, 3 caused by fall. Two cases of posterior coronal fractures combined with avulsion of posterior cruciate ligament and 1 case of posterolateral fractures associated with collapse fractures was treated via a S-shaped approach, 2 cases of posteromedial fracture via a posteromedial reversed L-shaped approach, another 3 cases of complex fractures involving anterior and posterior of tibial plateau, and metaphsis via a posteromedial reversed L-shaped approach combined with anterolateral approach. Fractures with articular surface collapse were applied with bone grafting. RESULTS: All the 8 cases were followed up for 8 to 39 months (means 20 months). All cases had attained bone union, the time of bone healing was 14.5 weeks in average ranging from 11 to 21 weeks. No infection, no blood vessel or nerve injuries and loosening or breakage of screw were found. There were no significant differences about the tibial plateau angle (TPA) and the posterior slope angle (PA) on radiographies between immediately after operation and 6 months after operation. According to the Rasmussen functional scoring,the results were excellent in 4, good in 3, fair in 1. Radiologic results were graded with the Rasmussen score to evaluate the reduction of the fracture, the scores at last followed-up was 14 to 18 scores (means 17.25), the results were excellent in 6, good in 2. CONCLUSION: Posterior S-shaped or L-shaped approach can facilitate the reduction and fixation with good exposure for posterior fractures of tibial plateau.