Liposome-exosome hybrids for in situ detection of exosomal miR-1246 in breast cancer.

Several lines of evidence suggest that exosomal miRNAs are potential biomarkers for cancer monitoring. An urgent need remains for the in situ detection of exosomal miRNAs at low concentrations without destroying the exosome structure. In the present study, a novel sensitive exosomal miR-1246 in situ detection strategy has been developed by integrating the CRISPR/Cas13a system with the formation of hybrids between exosomes and cationic liposomes. The liposomes were loaded with CRISPR/Cas13a, CRISPR RNA (crRNA), and RNA reporter probes. In the presence of exosomes, the liposome-exosome hybrids were formed through electrostatic interactions, and CRISPR/Cas13a was activated to cleave the reporter probes by exosomal miR-1246. The acquired fluorescence signal showed a linear response to the logarithm of MCF-7 exosome concentrations, indicating a quantitative response to exosomal miR-1246. The regression equation is y = 5021 log C - 9976 (R2 = 0.9985) with a limit of detection of 3 × 102 particles per mL. This strategy could not only be used to detect serum exosomal miR-1246 in breast cancer patients but also to distinguish early form advanced disease. This strategy can be exploited in future exosomal miRNA analyses.

A pH-Responsive DNA Tetrahedron/Methotrexate Drug Delivery System Used for Rheumatoid Arthritis Treatment.

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that leads to progressive and aggressive joint inflammation. The disease process is characterized by the activation of macrophages, which then release tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß), accelerating tissue damage. Tackling tissue damage is a crucial target in the treatment of RA. In this study, a macrophage-targeted and pH-response DNA tetrahedron/methotrexate drug delivery system was constructed by loading methotrexate (MTX) onto a DNA duplex. MTX was used as a drug model, and a pH-response DNA tetrahedron (TET) was used as the drug carrier, which was modified with hyaluronic acid (HA) to target macrophages. The aim of this study was to evaluate the potential of TET as an effective drug carrier for the treatment of RA. On this basis, we successfully prepared TETs loaded with MTX, and in vitro assays showed that the MTX-TET treatment could successfully target macrophages and induce macrophages to polarize to M1 phenotype. At the same time, we also injected MTX-TET intravenously into collagen-induced arthritis (CIA) model mice, and the redness and swelling of the paws of mice were significantly alleviated, proving that the MTX-TET could successfully target inflamed joints and release MTX to treat joint swelling. In addition, the histochemical results showed that the MTX-TET could reduce synovitis and joint swelling in CIA mice, reduce the level of inflammatory factors in vivo, and improve the disease status while maintaining a good biosafety profile. This study showed that the MTX-TET treatment has beneficial therapeutic effects on RA, providing a new strategy for the clinical treatment of RA.

An improved multi-scale branching convolutional neural network for rolling bearing fault diagnosis.

The vibration signals measured in practical engineering are usually complex and noisy, which brings challenges to fault diagnosis. In addition, industrial scenarios also put forward higher requirements for the accuracy and computational efficiency of diagnostic models. Aiming at these problems, an improved multiscale branching convolutional neural network is proposed for rolling bearing fault diagnosis. The proposed method first applies the multiscale feature learning strategy to extract rich and compelling fault information from diverse and complex vibration signals. Further, the lightweight dynamic separable convolution is elaborated and coupled into the feature extractor to "slim down" the model, reduce the computational loss on the one hand, and further improve the model's adaptive learning ability for different inputs hand. Extensive experiments indicate that the proposed method is significantly improved compared with existing multi-scale neural networks.

Ultrasonography-assisted assessment of the influence of the volar prominence of the plate on the median nerve in distal radius fractures.

OBJECTIVE: The study aimed to explore the effect of differing volar locking plate (VLP) prominence on the median nerve (MN) in distal radius fracture (DRF) with ultrasound assistance to guide clinical treatment. METHODS: Forty-four patients who received VLP for DRF at our department were admitted and followed-up between January 2019 and May 2021. Different plate positions were graded using Soong classification; 13 were Grade 0, 18 were Grade 1, and 13 were Grade 2. The MN parameters at different wrist positions in patients with different Soong grades were measured with ultrasound assistance, including the median nerve cross-sectional area (MNCSA), diameter in the radial-ulnar direction (D1), and diameter in the dorsal-palmar direction (D2). The sensation in the affected finger and grip strength were collected at follow-up, scored using the Disabilities of the Arm, Shoulder, and Hand (DASH) scale to determine function, and statistically analysed. RESULTS: The MNCSA differed significantly across Soong grades. The MNCSA at the flexed, neutral, and extended wrist positions was smallest at Grade 0 and largest at Grade 2 (P < 0.05), and that at the neutral position was not significantly different between Grades 1 and 2 (P > 0.05). There was no significant interaction between the wrist positions and Soong grade (P > 0.05). The differences in D1 and D2 among different Soong grades were not statistically significant (P > 0.05). There were no statistical differences in grip strength, DASH, and sensation among different Soong grades (P > 0.05). CONCLUSIONS: Differing plate protrusions in DRF treatment did not cause clinical symptoms during follow-up; however, excessive plate protrusion (Soong Grade 2) increased the cross-sectional area of the MN. We recommend placing the plate as proximal as possible during VLP treatment of DRFs to avoid excessive bulges affecting the MN.

Effect of nanoparticle-mediated delivery of SFRP4 siRNA for treating Dupuytren disease.

Dupuytren disease (DD) is a progressive fibrous proliferative disease. It invades the palmar aponeurosis and extends to the finger fascia, eventually leading to flexion contracture of the metacarpophalangeal or interphalangeal joint. At present, surgical resection and the local injection of collagenase are the main methods for the treatment of DD, but postoperative complications and high recurrence rates often occur. Bioinformatics analysis showed that the increased expression of SFRP4 protein was closely related to the incidence of DD. Persistent and effective inhibition of SFRP4 expression may be a promising treatment for DD. We prepared SFRP4 siRNA/nanoparticle complexes (si-SFRP4) and negative siRNA/nanoparticle complexes (NC) and applied them in vitro and in vivo. Flow cytometry analysis showed that si-SFRP4 could be successfully transfected into DD cells. MTT and EdU staining assays showed that the OD values and percentage of EdU-positive cells in the si-SFRP4 group were significantly lower than those in the NC group. Scratch tests showed that the wound healing rate of the si-SFRP4 group was lower than that of the NC group, and the difference was statistically significant. The expression of SFRP4 and α-SMA protein in the si-SFRP4 group significantly decreased in both DD cells and xenografts. Compared with the NC group, the xenograft quality of the si-SFRP4 group was significantly reduced. Masson's trichrome staining showed that the collagen and fibrous cells in the si-SFRP4 group were more uniform, slender, parallel and regular. The above experimental results suggest that the proliferation and metabolism of palmar aponeurosis cells and the quality of metacarpal fascia xenografts were both significantly decreased. We speculated that nanoparticle-mediated SFRP4 siRNA can be used as a potential new method for the treatment of DD.

Combined Use of Chitosan-PGLA Nerve Grafts and Bone Marrow Mononuclear Cells to Repair a 50-mm-long Median Nerve Defect Combined with an 80-mm-long Ulnar Nerve Defect in the Human Upper Arm.

BACKGROUND: Severe peripheral nerve injury, especially the long-distance peripheral nerve defect, causes severe functional disability in patients. There is always a lack of effective repair methods for clinic, and those in practice are associated with side effects. A case study was performed to observe the regenerative outcomes of the surgical repair of long-distance peripheral nerve defects in the upper arm with chitosan-poly(glycolide-co-lactide) (PGLA) nerve grafts combined with bone marrow mononuclear cells (BMMCs). METHODS: The right upper arm of a 29-year-old woman was injured, leaving a 50-mm-long median nerve defect, an 80-mm-long ulnar nerve defect, and muscle and blood vessel disruptions. The nerve defects were repaired by implanting BMMC-containing chitosan-PGLA nerve grafts on the 40th day after injury. A series of functional assessments were carried out from 2 weeks to 66 months after surgical repair. Sensory function was assessed by the pinprick test, two-point discrimination test and Semmes-Weinstein monofilament test. Motor function was evaluated by the range of motion of the wrist joint and muscle power. Autonomic function was monitored by laser-Doppler perfusion imaging (LDPI). Tissue morphology was observed through ultrasonic investigations. RESULTS: No adverse events, such as infection, allergy, or rejection, caused by the treatment were detected during the follow-up period. Sensory and pinprick nociception in the affected thumb, index, and middle fingers gradually restored at 6th month after surgery. The monofilament tactile sensation was 0.4 g in the terminal finger pulp of the thumb and index finger, 2.0 g in the middle finger, and greater than 300 g in the ring finger and little finger at the 66th month. Motor function recovery was detected at the 5th month after surgery, when the muscle strength of the affected forearm flexors began to recover. At the 66th month after surgery, the patient's forearm flexor strength was grade 4, with 80° of palmar flexion, 85° of dorsal extension, 8° of radial deviation, 40° of ulnar deviation, 40° of anterior rotation, and 85° of posterior rotation of the affected wrist. The patient could perform holding, picking up, and some other daily activities with the affected hand. The patient's sweating function of the affected hand was close to the level of the healthy hand. LDPI showed that the skin blood flow perfusion was significantly increased, with perfusion similar to on the normal side in some areas. Neuromusculoskeletal ultrasonography showed the presence of nerve structures. CONCLUSION: These results suggest that chitosan-PGLA nerve grafts combined with BMMCs could effectively repair long-distance nerve defects and achieve good clinical results.

Therapeutic effects of bone marrow mesenchymal stem cells-derived exosomes on osteoarthritis.

Mesenchymal stem cells (MSCs) have shown chondroprotective effects in clinical models of osteoarthritis (OA). However, effects of MSC-derived exosomes on OA remain unclear. The study aimed to investigate the therapeutic potential of exosomes from human bone marrow MSCs (BM-MSCs) in alleviating OA. The anterior cruciate ligament transection (ACLT) and destabilization of the medial meniscus (DMM) surgery were performed on the knee joints of a rat OA model, followed by intra-articular injection of BM-MSCs or their exosomes. In addition, BM-MSC-derived exosomes were administrated to primary human chondrocytes to observe the functional and molecular alterations. Both of BM-MSCs and BM-MSC-derived exosomes alleviated cartilage destruction and subchondral bone remodelling in OA rat model. Administration of BM-MSCs and exosomes could reduce joint damage and restore the trabecular bone volume fraction, trabecular number and connectivity density of OA rats. In addition, in vitro assays showed that BM-MSCs-exosomes could maintain the chondrocyte phenotype by increasing collagen type II synthesis and inhibiting IL-1ß-induced senescence and apoptosis. Furthermore, exosomal lncRNA MEG-3 also reduced the senescence and apoptosis of chondrocytes induced by IL-1ß, indicating that lncRNA MEG-3 might partially account the anti-OA effects of BM-MSC exosomes. The exosomes from BM-MSCs exerted beneficial therapeutic effects on OA by reducing the senescence and apoptosis of chondrocytes, suggesting that MSC-derived exosomes might provide a candidate therapy for OA treatment.

Resonance-based sparse adaptive variational mode decomposition and its application to the feature extraction of planetary gearboxes.

Due to the assumption that the VMD technique is essentially a set of adaptive Wiener filter banks and its performance depends to a large extent on the preset parameter K (the number of decomposition). A new method named resonance-based sparse adaptive variational mode decomposition (RSAVMD) is proposed for the decomposition of planetary gearbox vibration signals. Tunable Q-Factor Wavelet Transform (TQWT) and morphological component analysis (MCA) are introduced to decompose the original signal into high and low resonance components. High resonance components containing planetary gearbox signals are screened for analysis. At the same time, Quality factor is used to select the number of Variational mode decomposition (VMD) adaptively. This method was applied in fault diagnosis of planetary gearbox. Compared with VMD, RASVMD could extract fault characteristic frequency of planetary gearbox accurately, but VMD lost part of fault information, showing the superiority of RSAVMD. Simultaneously, the selection method of VMD decomposition number in literature was cited, and it was found that the decomposition number selected by the method in this paper was more accurate.

Upgraded bio-oil production via catalytic fast co-pyrolysis of waste cooking oil and tea residual.

Catalytic fast co-pyrolysis (co-CFP) offers a concise and effective process to achieve an upgraded bio-oil production. In this paper, co-CFP experiments of waste cooking oil (WCO) and tea residual (TR) with HZSM-5 zeolites were carried out. The influences of pyrolysis reaction temperature and H/C ratio on pyrolytic products distribution and selectivities of aromatics were performed. Furthermore, the prevailing synergetic effect of target products during co-CFP process was investigated. Experimental results indicated that H/C ratio played a pivotal role in carbon yields of aromatics and olefins, and with H/C ratio increasing, the synergetic coefficient tended to increase, thus led to a dramatic growth of aromatics and olefins yields. Besides, the pyrolysis temperature made a significant contribution to carbon yields, and the yields of aromatics and olefins increased at first and then decreased at the researched temperature region. Note that 600°C was an optimum temperature as the maximum yields of aromatics and olefins could be achieved. Concerning the transportation fuel dependence and security on fossil fuels, co-CFP of WCO and TR provides a novel way to improve the quality and quantity of pyrolysis bio-oil, and thus contributes bioenergy accepted as a cost-competitive and promising alternative energy.

Active skin perfusion and thermoregulatory response in the hand following nerve injury and repair in human upper extremities.

Cutaneous vasoconstriction/vasodilatation occurs in response to whole body and local cooling/heating, and the vasomotor activities play a pivotal role in thermal control of the human body. The mechanisms underlying regulation of skin blood flow involve both neurogenic and humeral/local chemical influence, contributing to the initial response to thermal stimuli and the prolonged phase of response, respectively. Previous studies have suggested the impairment of cutaneous thermal regulation after nerve injury. However, the evidence regarding how the skin perfusion and thermoregulatory response evolve after nerve injury and repair remains limited. Here we observed, by utilizing laser-Doppler perfusion imaging, baseline skin perfusion and perfusion change in response to thermal stimuli after median and ulnar nerve injury, and the results showed that baseline perfusion in autonomous skin area profoundly decreased and active rewarming after clod stress dramatically diminished before sensory recovery of the skin became detectable. In addition, baseline cutaneous perfusion was recovered as the skin regained touch sensation, and exhibited positive correlation to touch sensibility of the skin. These data indicate that both active perfusion and thermoregulatory response of the skin are markedly compromised during skin denervation and can be recovered by re-innervation. This suggests the importance of timely repair of injured nerve, especially in the practice of replantation.

Laser doppler perfusion imaging of skin territory to reflect autonomic functional recovery following sciatic nerve autografting repair in rats.

Peripheral nerve repair requires comprehensive evaluation of functional outcomes of nerve regeneration; however, autonomic nerve function is seldom evaluated probably due to lack of suitable quantitative methods. This study sought to determine whether autonomic functional recovery could be reflected by cold-induced vasodilation (CIVD) within target skin territory, as monitored by laser Doppler perfusion imaging (LDPI). Rats with sciatic nerve defect injury received autologous nerve grafting, and the plantar surface of the hind feet was subjected to LDPI analysis following nerve repair. The results indicated that at 3 and 6 months after autologous nerve grafting, the plantar surface of the hind foot exhibited the same level of CIVD as contralateral normal side, whereas rats in nerve defect group (negative control) showed significantly reduced CIVD. In addition, suitable nerve regeneration and functional recovery were achieved as assessed by pain sensation tests as well as electrophysiological and immunohistological examinations. Based on the potential influence of local autonomic nerve signals on CIVD, it was possible to evaluate functional recovery of autonomic nerves by using LDPI measurements of dermal CIVD.

Surgical repair of a 30 mm long human median nerve defect in the distal forearm by implantation of a chitosan-PGA nerve guidance conduit.

This paper describes a clinical case study in which a chitosan/polyglycolic acid nerve guidance conduit (chitosan-PGA NGC) was utilized to repair a 30 mm long median nerve defect in the right distal forearm of a 55 year-old male patient. Thirty-six months after the nerve repair, the palm abduction of the thumb and the thumb-index digital opposition recovered, facilitating the patient to accomplish fine activities, such as handling chopsticks. Static two-point discrimination measured 14, 9 and 9 mm in the thumb, index and middle fingers of the right hand. Reproducible compound muscle action potentials were recorded on the right abductor pollicis. The ninhydrin test, a classical method for assessing sympathetic nerve function, showed partial recovery of the perspiration function of the injured thumb, index and middle fingers. This repair case suggested a possible strategy for the clinical reconstruction of extended defects in human peripheral nerve trunks by the implantation of chitosan-PGA NGCs.

Polyglycolic acid filaments guide Schwann cell migration in vitro and in vivo.

Nerve conduits filled with longitudinal aligned filaments have demonstrated a better regenerative outcome for bridging large peripheral nerve gaps than hollow nerve conduits. In the present study, we investigated the in vitro and in vitro cellular behavior of Schwann cells on polyglycolic acid (PGA) filaments by immunocyto/histochemistry and light/electron microscopy. After 1-3-week culture of rat dorsal root ganglia (DRGs) onto PGA filaments, Schwann cells from rat DRGs adhered to and migrated along PGA filaments. Twenty-four rats received implantation of chitosan conduits inserted with PGA filaments to bridge 10-mm-long sciatic nerve gaps. At 1, 2, 3 and 4 weeks post-implantation (n = 6, each time point), Schwann cells were found to migrate along PGA filaments and form cell columns resembling bands of Büngner. These results suggest that PGA filaments may play a contact guidance role in Schwann cell migration and thus serve as a promising conduit-filling material to facilitate peripheral nerve repair.

Repairing a 35-mm-long median nerve defect with a chitosan/PGA artificial nerve graft in the human: a case study.

We have developed a chitosan/polyglycolic acid (PGA) artificial nerve graft which was previously used for bridge implantation of dog sciatic nerves across 30-mm long defects. Here we describe a clinical trial of this graft for repairing a 35-mm-long median nerve defect at elbow of a human patient. During the 3-year follow-up period, functional recovery of the injured median nerve was assessed by pinch gauge test, hydraulic hand dynamometry, static two-point discrimination and touch test with monofilaments, in couple with electrophysiological examinations. The motor and sensory function of the median nerve demonstrated an ongoing recovery postimplantation, reaching M4 and S3+ levels during the follow-up period. The results indicate that the chitosan/PGA artificial nerve graft could be used for surgical repair of larger defects in major peripheral nerves at a higher level in the human.