Wear Performance of Circular Shim against Cam in Engine Bench Test.

Unlike the conventional engine, the valve train of a certain type of engine uses a circular shim instead of a tappet to wear against the cam. To verify the reliability of the shim, an engine bench test was used to test its wear performance. The total duration of the bench test was 1000 h, which was divided into three stages. In each stage, the test equipment was stopped, and the shims were disassembled to observe the surface morphology during the worn process. Precious long-term data were obtained. With the extension of the bench test time, weight loss increased. The maximum weight loss occurs 1000 h after worn, which is about twice that of 350 h. During the wear process, a plastic flow of material was found on the subsurface, and fatigue wear marks occurred on the surface. With an increase in test time, the wear marks increased, leading to material spalling and the formation of pits. The wear mechanism was the mixed wear of fatigue wear and adhesive wear.

Combined antisclerostin antibody and parathyroid hormone (1-34) synergistically enhance the healing of bone defects in ovariectomized rats.

Osteoporotic bones heal more slowly and ineffectively than normal bones. A combination of antibodies against sclerosing protein (Scl-Ab), and parathyroid hormone 1-34 (PTH 1-34) may improve healing. A standard osteoporotic rat model was established 12 weeks after bilateral ovarian resection (OVX). Bone defects were created in the right femora of 80 rats, which were randomly divided into 4 groups: control, Scl-Ab (25 mg/kg twice weekly), PTH (60 µg/kg of PTH 1-34 three times a week) and PTH plus Scl-Ab. After 12 weeks of treatment the rats were sacrificed and blood and the distal femora were harvested for biochemical evaluation, histology, microcomputed tomography and biomechanical testing. Compared to the control group, monotherapy and combination therapy with PTH and/or Scl-Ab promoted the formation of new bone, enhanced maximum femoral loading and increased the levels of procollagen type I N­terminal propeptide (PINP) and osteocalcin. The administration of PTH + Scl-Ab maximally enhanced bone defect healing. Combination treatment was better than either treatment alone, indicating a synergistic effect.

Protective effects of resveratrol on random-pattern skin flap survival: an experimental study.

Random-pattern skin flap transplantation is a common procedure in plastic surgery, but its distal area usually incurs ischemia and necrosis. Resveratrol (Rev), a natural polyphenol primarily found in peanuts, grapes, and red wine, which exerts multi-bioactivity. In this study, forty-eight rats with the modified "McFarlane flap" model were divided into Control and Rev groups, which were treated with vehicle Control and Rev, respectively. After 7 days of continuous treatment and observation, ischemic flap tissues were harvested to evaluate angiogenesis, apoptosis, oxidative stress, and autophagy. It was observed a greater survival area of flaps, accompanied with reduced water content and stronger blood supply, in the Rev group than in the Control group. In addition, Rev upregulated the expression of MMP9, VEGF, and Cadherin5, indicating that Rev promotes angiogenesis in ischemic flaps. Moreover, Rev decreased the levels of Bax, CYC, and Caspase3, suggesting that it inhibits apoptosis. Besides, Rev increased the expression of SOD1, eNOS, HO1, the activities of SOD and GSH, and reduced the levels of MDA, which uncovers that it depresses oxidative stress in ischemic flaps. Finally, it increased the expression of Beclin1, LC3II, VPS34, and CTSD, and decreased SQSTM1/p62 levels, which reveals that it activates autophagy in the flaps. These results suggest that Rev promotes random skin flap survival through proangiogenic, antiapoptotic, and antioxidative effects; moreover, autophagy is activated in the process, which might be another underlying mechanism for the flap survival.

Salvianolic Acid B Promotes the Survival of Random-Pattern Skin Flaps in Rats by Inducing Autophagy.

Random-pattern skin flap transplantation is frequently applied in plastic and reconstructive surgery. However, the distal part of the flap often suffers necrosis due to ischemia. In this study, the effects of salvianolic acid B (Sal B) on flap survival were evaluated, and the underlying mechanisms were investigated. Sal B improved the survival area, reduced tissue edema, and increased the number of microvessels in skin flaps after 7 days, whereas an autophagy inhibitor (3-methyladenine) reversed the Sal B-induced increase in flap viability. In addition, Sal B stimulated angiogenesis, inhibited apoptosis, reduced oxidative stress, and upregulated autophagy in areas of ischemia. Moreover, the effects of Sal B on angiogenesis, apoptosis, and oxidative stress were reversed by autophagy inhibition. Overall, our findings suggest that Sal B has pro-angiogenesis, anti-apoptosis, and anti-oxidative stress effects by stimulating autophagy, which enhances the survival of random-pattern skin flaps.

Effects of the traditional Chinese medicine baicalein on the viability of random pattern skin flaps in rats.

BACKGROUND: Random skin flaps are routinely placed during plastic and reconstructive surgery, but the distal areas often develop ischemia and necrosis. Baicalein, a major flavonoid extracted from the traditional Chinese herbal medicine huangqin, Scutellaria baicalensis Georgi, may improve flap viability. MATERIALS AND METHODS: Rats were randomly divided into baicalein and control groups and they underwent placement of modified McFarlane flaps after intraperitoneal administration of baicalein or vehicle. Flap survival and water content were measured 7 days later, as were angiogenesis, apoptosis, and oxidative stress in ischemic flaps. RESULTS: Baicalein promoted flap survival, reduced edema, increased mean vessel density, and enhanced vascular endothelial growth factor production at both the translational and transcriptional levels. Baicalein reduced caspase 3 cleavage, increased superoxidase dismutase and glutathione levels, and decreased the malondialdehyde level. CONCLUSION: Baicalein promoted flap viability by stimulating angiogenesis and inhibiting apoptosis and oxidation.

Does Timing of Surgery Affect Treatment of the Terrible Triad of the Elbow?

BACKGROUND This study investigated the influence of surgical timing on the treatment of terrible triad of the elbow (TTE). MATERIAL AND METHODS After exclusion, 63 patients were enrolled in this study: 20 patients were classified into the emergency group (group A, within 24 h after injury), 26 into the early surgery group (group B, from 4 to 14 days after injury), and 17 into the delayed surgery group (group C, more than 14 days after injury). All patients underwent the same approach, and elbow motion and complication rates were recorded and compared. RESULTS Fifty-eight patients were followed up (mean 20.5±1.9 months), and 5 patients had lost partial final data. At 1 month after the operation, elbow motion in group A was higher than in group B and group C (P<0.01); however, 3 or more months later, there was no distinct difference between group A and group B (P>0.05), while both group A and group B showed better outcomes than group C at all time points (P<0.05). Moreover, group A and group B had better higher elbow motion, MEPS, excellent and good rate than group C at the final clinical visit (all P<0.05). No postoperative pain or complication rate differences were found among the 3 groups except for elbow stiffness (2 in group A, 3 in group B, and 7 in group C) (P<0.05) which required reoperation to enhance elbow function. CONCLUSIONS Emergency or early operation for TTE patients were more effective than delayed operation.

Long Noncoding RNA FEZF1-AS1 Promotes Osteosarcoma Progression by Regulating the miR-4443/NUPR1 Axis.

Long noncoding RNA (lncRNA) FEZF1-AS1 was demonstrated to facilitate cell proliferation and migration in some cancers. However, the functions of FEZF1-AS1 and its molecular mechanism in osteosarcoma remain to be elucidated. In our study, we found that the expression of FEZF1-AS1 was upregulated in osteosarcoma samples and cell lines compared with normal tissues or cells. Besides, we showed that the expression levels of FEZF1-AS1 in osteosarcoma patients were positively correlated with tumor metastasis and TNM stage. Additionally, FEZF1-AS1 knockdown inhibited cell proliferation, migration, and invasion in U2OS and MG63 cells, while upregulation had the opposite effects in vitro. Moreover, FEZF1-AS1 depletion inhibited tumor growth and metastasis in vivo. We found that FEZF1-AS1 sponged miR-4443 to promote NUPR1 expression in U2OS and MG63 cells. Furthermore, knockdown of miR-4443 abrogated FEZF1-AS1 silencing-induced inhibition of cell proliferation, migration, and invasion in osteosarcoma. Finally, we found that restoration of NUPR1 rescued the proliferation, migration, and invasion abilities of FEZF1-AS1-depleted U2OS and MG63 cells. Our study indicated that FEZF1-AS1 could promote osteosarcoma progression by sponging miR-4443 to promote NUPR1 expression. The FEZF1-AS1/miR-4443/NUPR1 axis may act as a novel therapeutic strategy for osteosarcoma treatment.

Comparison of a single approach versus double approaches for the treatment of terrible traid of elbow-A retrospective study.

INTRODUCTION: Dislocation of the elbow associated with radial head and coronoid fracture, the so-called "terrible triad" of the elbow, is challenging to treat and has a history of complicated outcomes. This study is to compare the clinical outcome of a single lateral approach-the extensile splitting extensor digitorum communis (EDC) approach and combined lateral and medial (CML) approaches for the treatment of terrible traid of the elbow (TTE). MATERIAL AND METHODS: After appropriate exclusion, 60 TTE patients (28 patients in the EDC group, 32 patients in the CML group) from 2009 January to 2015 August were reviewed in this study. All included patients underwent open reduction, lateral collateral ligament complex repair, and postoperative function exercise. Surgical time, intraoperative blood loss, postoperative pain, elbow motion, MEPS score and complication rate were recorded and compared. RESULT: There were significant differences in surgery time (P < 0.05) and ulnar nerve lesion symptom, no patient suffered ulnar nerve lesion symptom in EDC group, but 5 patients in CML group suffered it. No differences were found in intraoperative blood loss, postoperative pain and heterotopic ossification (P > 0.05). Mean follow-up was 26.1 months (from 24 to 30 months), at the final follow-up, 2 patients in EDC group and 4 patients in CML group required elbow release operation, mean flexion and extension (124.1 ±â€¯14.6°and 8.3 ±â€¯5.3°), pronation and supination (73.4 ±â€¯5.3° and 74.4 ±â€¯6.0°) in EDC group were higher than CML group (114.2 ±â€¯15.0° and 17.6 ±â€¯8.0°, 69.2 ±â€¯6.9° and 70.4 ±â€¯7.5°, P < 0.05). Besides, MEPS score in the former group was also higher than the latter group (91.8 ±â€¯4.5 to 84.4 ±â€¯5.2, P < 0.01). CONCLUSION: The single lateral approach achieved better function recovery than combined lateral and medial approach, decreasing the risk of ulnar nerve lesion and surgery time for the treatment of TTE.

Multifaceted effects of astragaloside IV on promotion of random pattern skin flap survival in rats.

Random pattern skin flap transplantation is frequently applied in plastic and reconstructive surgery, but the distal part of skin flaps often suffers necrosis due to ischemia. Astragaloside IV (AS-IV), a natural saponin purified from Astragalus membranaceus, may have beneficial functions for flap survival. In this study, rats were divided into a control group and an AS-IV treatment group, and underwent surgery using a modified "McFarlane flap" model. After intragastric administration of vehicle control or AS-IV for their respective groups, flap survival area and water content were measured 7 days after surgery. Flap tissue was separated to test protein expressions related to angiogenesis, inflammation, oxidative stress and autophagy via western blot, immunohistochemistry, and immunofluorescence. Results showed that AS-IV improved flap survival area and reduced tissue edema. AS-IV also increased mean vessel densities and upregulated levels of VEGF protein, both of which indicate increased angiogenesis. Furthermore, AS-IV depressed leukocyte infiltration, decreased expressions of inflammatory proteins TNF-α, IL1ß and IL6, increased SOD activity, decreased MDA content, and stimulated autophagy. Overall, our results suggest that AS-IV promotes skin flap survival via inducing angiogenesis, depressing inflammation and dampening oxidative stress; it also activates autophagy, which may be an underlying mechanism for oxidative stress depression.