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Tyrosinase is inextricably related to the development of Alzheimer’s disease. The effects of natural tyrosinase inhibitors on human health have attracted widespread attention. This study aimed to isolate and analyze the tyrosinase (TYR) inhibitory peptides in the enzymatic digestion products of royal jelly. We first analyzed optimal process conditions for the enzymatic digestion of royal jelly by single-factor and orthogonal experiments and then used gel filtration chromatography to obtain five fractions (D1~D5) with molecular weights ranging from 600 to 1100 Da. LC-MS/MS was applied to identify the fractions with the highest activity, and the obtained peptides were screened and molecularly docked using AutoDock Vina. The results showed that the optimal enzymatic conditions for tyrosinase inhibition rate were acid protease, enzyme addition 10,000 U/g, initial pH 4, feed-to-liquid ratio 1:4, enzymatic temperature 55 °C, and enzymatic time 4 h. The D4 fraction had the most significant TYR inhibitory activity. The IC50 values of the three new peptides with the strongest TYR inhibitory activity, TIPPPT, IIPFIF, and ILFTLL, were obtained as 7.59 mg/mL, 6.16 mg/mL, and 9.25 mg/mL, respectively. The molecular docking results showed that aromatic and hydrophobic amino acids were more favorable to occupy the catalytic center of TYR. In conclusion, the new peptide extracted from royal jelly has the potential to be used as a natural TYR inhibitory peptide in food products with health-promoting properties.

Background The purpose of this study was to evaluate the clinical and radiographic outcomes after medial patellofemoral ligament (MPFL) reconstruction combined with supracondylar biplanar femoral derotation osteotomy (FDO) in recurrent patellar dislocation (RPD) with increased femoral anteversion angle (FAA) and genu valgum. Methods Between January 2017 to December 2020, a total of 13 consecutive patients (13 knees, 4 males and 9 females, mean age 18.7 (range, 15–29 years) with RPD with increased FAA (FAA > 25°) and genu valgum (mechanical axis deformity of ≥5°) who underwent supracondylar biplanar FDO using a Tomofix-locking plate combined with MPFL reconstruction in our institution were included. Preoperative full-leg standing radiographs, lateral views, and hip-knee-ankle computed tomography (CT) scans were used to evaluate the mechanical lateral distal femoral angle (mLDFA), anatomical femorotibial angle (aFTA), mechanical axis, patellar height, tibial tubercle-trochlear groove (TT-TG) distance, and torsional angle of the tibial and femoral in the axial plane. Patient reported outcomes were evaluated using the International Knee Documentation Committee (IKDC) score, Kujala score, Lysholm score, visual analog scale (VAS), and Tegner score preoperatively and postoperatively. Postoperative CT scans were used to evaluate the changes of FAA and TT-TG, and full-leg standing radiographs was used to evaluate the changes of mLDFA, aFTA, and mechanical axis. Results A total of 13 patients (13 knees) were included with an average follow-up period of 26.7 months (range 24–33). No cases developed wound infection, soft tissue irritation, and recurrent patellar dislocation during the follow-up period after surgery. Bone healing at the osteotomy site was achieved in all cases, and all patients regained full extension and flexion. Clinical outcomes (VAS, Kujala, IKDC, Lysholom, and Tegner scores) improved significantly at the final follow-up after surgery (p p p>0.05). Conclusion MPFL reconstruction combined with supracondylar biplanar FDO showed satisfactory clinical outcomes and radiographic results in the short-term follow-up period.

Vibrio mimicus (V. mimicus) is a pathogen causing serious vibriosis in aquatic animals. Hepcidin and β-Defensin1 are two important antibacterial peptides (AMPs) with broad-spectrum antibacterial activity in fish. In mammals, some evidences demonstrated that interleukin-1β (IL-1β) primarily promote AMPs expression via activating classical NF-κB pathway, but it still remains unclear in fish. Here, the temporal and spatial expression patterns of grass carp IL-1β (gcIL-1β) gene and two AMPs genes (gchepcidin and gcβ-defensin1) in tissues post-V. mimicus infection and anti-V. mimicus activity of these two AMPs in vitro were detected, showing that V. mimicus infection significantly elevated the mRNA levels of these three genes in the immune-related tissues although their expression patterns were not entirely consistent, and both gcHepcidin and gcβ-Defensin1 possessed anti-V. mimicus activity in vitro. Subsequently, the recombinant gcIL-1β (rgcIL-1β) was expressed prokaryotically in an inclusion body, which could promote proliferation of grass carp head kidney leukocytes (gcHKLs) and enhance respiratory burst activity and phagocytic activity of head kidney macrophages. Stimulation with rgcIL-1β was able to significantly regulate the mRNA expression of key regulatory genes (il-1RI, traf6, tak1, ikkβ, iκBα and p65) involved in the activation of classical NF-κB pathway, and then induce gcTAK1 phosphorylation, promote gcp65 nuclear translocation and enhance endogenous gcIL-1β expression at both mRNA and protein levels, implying NF-κB pathway was activated. More importantly, exogenous rgcIL-1β stimulation also significantly up-regulated both gcHepcidin and gcβ-Defensin1 mRNA levels against V. mimicus, and the regulatory effect was blocked or inhibited by NF-κB inhibitor PDTC. Taken together, our results demonstrated for the first time that grass carp IL-1β stimulation could significantly enhance the expression of these two anti-V.mimicus AMPs via activating classical NF-κB pathway.

Background: Metallic foreign body migration into the pulmonary artery after limb trauma is extremely rare. If not treated in time, the patient may die. The metallic foreign body was implanted from the thigh into the pulmonary artery and remained for 5 years. It has never been reported in limb trauma.Case Presentation: The patient was a 51-year-old male who had a small metal foreign body embedded in the middle and lower left thigh due to trauma. The foreign body was not found during emergency debridement operation. During the operation, a full-body X-ray was used to reveal a high-density shadow in the left upper lung. The 3D-CT of the chest immediately confirmed that the high-density shadow was a small iron foreign body, and the iron fragment foreign body was present in the pulmonary artery branch, but no abnormal symptoms were observed. He was hospitalized for observation for 3 days without obvious discomfort and refused to open his chest. The patient then decided to leave the hospital voluntarily.Conclusion: Surgical removal of all foreign bodies traveling to the pulmonary artery is not necessary, and the most appropriate treatment plan should be made considering the location of the foreign body, the patient's wishes and the general condition.

Background Symptomatic pulmonary embolism (PE) after knee arthroscopy is extremely rare. If the embolism is not treated promptly, the patient may die. Bilateral pulmonary embolism with associated pulmonary infarct without concomitant deep vein thrombosis has never been reported following routine knee arthroscopy. Case presentation A 50-year-old female patient with no other risk factors other than hypertension, obesity, varicose veins in the ipsilateral lower extremities and elevated triglyceride (TG) presented to our ward. She had experienced sudden chest tightness, polypnea and fainting after going to the bathroom the morning of the second postoperative day and received emergency medical attention. Colour ultrasonography of the extremities showed no deep vein thrombosis. Lung computed tomography angiography (CTA) showed multiple embolisms scattered in both pulmonary artery branches. Thus, emergency interventional thrombolysis therapy was performed, followed by postoperative symptomatic treatment with drugs with thrombolytic, anticoagulant and protective activities. One week later, lung CTA showed a significant improvement in the PEs compared with those in the previous examination. Since the aetiology of PE and no obvious symptoms were discerned, the patient was discharged. Conclusion Although knee arthroscopy is a minimally invasive and quick procedure, the risk factors for PE in the perioperative period should be considered and fully evaluated to enhance PE detection. Moreover, a timely diagnosis and effective treatment are important measures to prevent and cure PE after knee arthroscopy. Finally, clear guidelines regarding VTE thromboprophylaxis following knee arthroscopy in patients with a low risk of VTE development are needed.

Recurrent patellar dislocation (RPD) is multifactorial disease, and excessive femoral internal torsion has been considered as an important risk factor for recurrence of patellar dislocation and graft failure after surgery 1 . Satisfactory clinical outcomes depend on correcting of the pathologic abnormalities around the patellofemoral joint and torsional deformity of the lower extremity. At present, conventional isolated medial patellofemoral ligament (MPFL) reconstruction without addressing excessive femoral internal torsion may lead to MPFL graft failure 2,3 , because increased femoral internal torsion can significantly increase a persistently lateralizing force on the patella 4 . Considering these predisposing factors and to provide an optimal treatment for RPD with increased femoral internal torsion, we presented our surgical technique regarding the clinical application of MPFL reconstruction combined with supracondylar femoral derotation osteotomy, and make a brief introduction of its surgical techniques. A 21-year-old female was initially admitted to our hospital for complaining her patellofemoral joint due to the recurrence dislocation (＞2 times). The full-leg standing anteroposterior (AP) radiographs, lateral views, and axial images showed that the normal patellar height and morphology of trochlea, neutral alignment of the lower extremity, while the hip-knee-ankle scans of 3-d reconstructive axial images identified that the femoral anteversion angle was increased to 32.4°. The degree of tibial external was 18.6° and the tibial tuberosity-trochlear groove (TT-TG) distance was 18.6 mm, demonstrating the normal TT-TG distance and tibial external (Fig.1). After that, the patient treated by double-bundle anatomical MPFL reconstruction combined with supracondylar femoral derotation osteotomy procedure.

Vibration is an important comfort issue for the metro surrounding buildings. Among the many methods of subway vibration control, building isolation is the necessary supplement to the track isolation for metro surrounding buildings with sensitive constructive forms or specific comfort needs. Laminated rubber bearings are widely used for the building isolation. In order to further improve the isolation effectiveness, researchers intend to use laminated rubber bearings with relatively thick rubber layers. However, the frequency dependency and temperature dependency are not well explored for the thick rubber bearings. And since constrains from the steel plates to rubber layers are relatively small for thick rubber bearings, its not clear if it is accurate to simply apply the equations for common laminated rubber bearings to the thick ones. In this paper, a compressive properties test is carried out for both thick and thin rubber bearings. Both thick and thin rubber bearings are manufactured by a kind of High Damping Rubber (HDR) and a kind of Nature Rubber (NR). The frequency dependency and temperature dependency are tested. The accuracy of applying the current design equations to thick rubber bearings is discussed based on the test results.