Signaling Mechanisms of Stem Cell Therapy for Intervertebral Disc Degeneration.

Low back pain is the leading cause of disability worldwide. Intervertebral disc degeneration (IDD) is the primary clinical risk factor for low back pain and the pathological cause of disc herniation, spinal stenosis, and spinal deformity. A possible approach to improve the clinical practice of IDD-related diseases is to incorporate biomarkers in diagnosis, therapeutic intervention, and prognosis prediction. IDD pathology is still unclear. Regarding molecular mechanisms, cellular signaling pathways constitute a complex network of signaling pathways that coordinate cell survival, proliferation, differentiation, and metabolism. Recently, stem cells have shown great potential in clinical applications for IDD. In this review, the roles of multiple signaling pathways and related stem cell treatment in IDD are summarized and described. This review seeks to investigate the mechanisms and potential therapeutic effects of stem cells in IDD and identify new therapeutic treatments for IDD-related disorders.

Advances in the Repair of Palmer type IB TFCC Injuries With Wrist Arthroscopy.

The triangular fibrocartilage complex (TFCC) is essential for maintaining wrist stability. Injury-caused pain is the primary cause of ulnar wrist pain. The TFCC injury refractory to conservative treatment requires further surgical treatment, and because Palmer type IB tears belong to peripheral injuries due to their proximity to the blood supply area, arthroscopic suture repair has become the preferred surgical method for TFCC injury repair, exhibiting strong healing ability. This study reviewed the anatomy of TFCC, injury classification, and advances in arthroscopic suturing for treating Palmer type IB.

Pseudoaneurysm of the brachial artery in an infant due to vaccination: a case report.

BACKGROUND: Pseudoaneurysm is a known complication of penetrating arterial injuries such as catheterization, gunshot wounds, and open fractures. Vaccination is an effective method for preventing multiple, serious, infectious diseases in children. Common adverse reactions related to vaccination include fever, swelling, redness, and pain. Brachial pseudoaneurysm after vaccination has not been previously reported. CASE PRESENTATION: Herein we describe a novel case of brachial pseudoaneurysm after vaccination in a child aged 1 year and 3 months. A pulsatile mass was formed in the medial left arm of the infant 10 days after vaccination at a community hospital and gradually grew larger. Preoperative images depicted an eccentric aneurysm in the brachial artery and a swirling flow pattern in the mass. The pseudoaneurysm was excised, and vein graft interpositioning was successfully performed. There were no short-term or long-term complications during the follow-up period. CONCLUSIONS: Brachial pseudoaneurysm is a rare complication of vaccination via intramuscular injection. Medical staff should avoid puncture wounds to the brachial artery during vaccination, especially in infants.

Treatment of dorsal wrist ganglion cyst by establishing midcarpal volar portal using the "Kiss-in" method.

Introduction: This paper introduces the treatment and clinical outcome of the dorsal wrist ganglion cyst utilizing the Kiss-in method to establish a midcarpal volar portal. Materials and methods: Patients with dorsal ganglia of the wrist (n = 12, 6 females, 6 males) underwent arthroscopic surgery using the Kiss-in method at our hospital between September 2018 and January 2021. All patients underwent preoperative radiological investigations, such as magnetic resonance imaging (MRI; 12 cases) or ultrasonography (12 cases). The mean age of patients was 30.7 years (range: 19-46 years). The time lost from work, the wrist motion and strength, the presence of scarring, residual symptoms, complications, and recurrence were recorded at a mean follow-up of 24 months. Results: Eleven patients showed a good prognosis with active motion recovery. One patient showed the recurrence of ganglion, and the second arthroscopic resection was performed 5 months after the first surgery for this patient. After the surgery, the patient fully recovered. Conclusions: Establishing the midcarpal volar portal by the Kiss-in method is safe. The dorsal ganglion cyst resection through the established midcarpal volar portal is a promising approach, allowing better visualization and a broader range motion of the arthroscope.

Mesoporous polydopamine nanoparticles for sustained release of rapamycin and reactive oxygen species scavenging to synergistically accelerate neurogenesis after spinal cord injury.

Spinal cord injury (SCI) is an intractable condition with complex pathological processes and poor prognosis. Reactive oxygen species (ROS) generation induced by the mammalian target of the rapamycin (mTOR) protein is one of the causes of secondary inflammation of SCI. Rapamycin (Rapa) is a pharmacological inhibitor of mTOR, which can inhibit ROS overproduction mediated by abnormal activation of the mTOR protein. Polydopamine, as a nanocarrier with excellent biological safety, has been reported to possess satisfactory ROS scavenging ability. Therefore, we designed a mesoporous polydopamine nanoparticle loaded with Rapa (mPDA@Rapa) for combination therapy, which simultaneously inhibited abnormally activated mTOR-mediated ROS production and eliminated already generated ROS. The synthesized mPDA nanoparticles could realize the effective encapsulation and sustained release of Rapa due to their mesoporous cavities and a hydrophobic benzene ring structure. In vitro experiments proved that mPDA@Rapa nanoparticles had a good ROS scavenging ability towards hydrogen peroxide and hydroxyl radicals. Furthermore, mPDA@Rapa also showed a good therapeutic effect in SCI model rats, which was evidenced by a smaller injury cavity, more coordinated hind limb movements, and a higher degree of neurogenesis and tissue regeneration. Our work provides a combined strategy to inhibit ROS overproduction and eliminate excess ROS, with potential applications not only in SCI, but also in other ROS-induced inflammations.

Injection Injury Caused by Disinfectant During COVID-19: A Case Report.

High-pressure injection injury of the hand is a rare but severe emergency, which requires full attention and timely treatment. However, the early symptoms may not be obvious. As the swelling and necrosis progress, the condition gradually worsens, and in severe cases, it may end with amputation. We report a particular case of a hand injection injury, which occurred to a worker who worked overtime to produce disinfectant during the Coronavirus Disease-19 (COVID-19) pandemic. Because of the chemical toxicity of the disinfectant and pressure's damage, although the emergency debridement was promptly performed, we still lost some fingers in the end. In the existing disinfection product manuals, we have not seen any tips on dealing with tissue injection injury. It may reduce workers' attention to injuries, leading to delays in emergency operations.

Micropatterns and peptide gradient on the inner surface of a guidance conduit synergistically promotes nerve regeneration in vivo.

Both of the surface topographical features and distribution of biochemical cues can influence the cell-substrate interactions and thereby tissue regeneration in vivo. However, they have not been combined simultaneously onto a biodegradable scaffold to demonstrate the synergistic role so far. In this study, a proof-of-concept study is performed to prepare micropatterns and peptide gradient on the inner wall of a poly (D,L-lactide-co-caprolactone) (PLCL) guidance conduit and its advantages in regeneration of peripheral nerve in vivo. After linear ridges/grooves of 20/40 µm in width are created on the PLCL film, its surface is aminolyzed in a kinetically controlled manner to obtain the continuous gradient of amino groups, which are then transferred to CQAASIKVAV peptide density gradient via covalent coupling of glutaraldehyde. The Schwann cells are better aligned along with the stripes, and show a faster migration rate toward the region of higher peptide density. Implantation of the nerve guidance conduit made of the PLCL film having both the micropatterns and peptide gradient can significantly accelerate the regeneration of sciatic nerve in terms of rate, function recovery and microstructures, and reduction of fibrosis in muscle tissues. Moreover, this nerve conduit can also benefit the M2 polarization of macrophages and promote vascularization in vivo.

Restoration of forearm supination by combining pronator teres with allogeneic tendon.

BACKGROUND: Many solutions have been proposed in treating of forearm supination. Comparing with other supination function reconstructions, pronator teres rerouting is believed to be less effective due to its insufficient supination strength. The aim of this study is to introduce a modified procedure, and compare its result with two previous approaches. PATIENTS AND METHODS: From 2015 to 2020, 11 patients have restored forearm supination by rerouting of the pronator teres weave sutured with allogeneic tendons. The average follow-up period was 17.5 months (12 to 24). The range of active supination at the final follow-up was recorded. RESULTS: Almost all patients acquired good supination range. The average active post-operative supination was 72.7° (60° to 80°) at the final follow-up. No complication was observed. All patients retained full range of pronation. CONCLUSIONS: This study provides a modified supination function reconstruction with simple operating, fine results, low risks, and no affecting of pronation function. The use of allogeneic tendon makes up for the muscles with insufficient length, making it valuable to reconsider those rebuilding operations that were once considered unpromising by many.

High-metastatic cancer cells derived exosomal miR92a-3p promotes epithelial-mesenchymal transition and metastasis of low-metastatic cancer cells by regulating PTEN/Akt pathway in hepatocellular carcinoma.

Exosomes play an important role in intercellular communication and metastatic progression of hepatocellular carcinoma (HCC). However, cellular communication between heterogeneous HCC cells with different metastatic potentials and the resultant cancer progression are not fully understood in HCC. Here, HCC cells with high-metastatic capacity (97hm and Huhm) were constructed by continually exerting selective pressure on primary HCC cells (MHCC-97H and Huh7). Through performing exosomal miRNA sequencing in HCC cells with different metastatic potentials (MHCC-97H and 97hm), many significantly different miRNA candidates were found. Among these miRNAs, miR-92a-3p was the most abundant miRNA in the exosomes of highly metastatic HCC cells. Exosomal miR92a-3p was also found enriched in the plasma of HCC patient-derived xenograft mice (PDX) model with high-metastatic potential. Exosomal miR-92a-3p promotes epithelial-mesenchymal transition (EMT) in recipient cancer cells via targeting PTEN and regulating its downstream Akt/Snail signaling. Furthermore, through mRNA sequencing in HCC cells with different metastatic potentials and predicting potential transcription factors of miR92a-3p, upregulated transcript factors E2F1 and c-Myc were found in high-metastatic HCC cells promote the expression of cellular and exosomal miR-92a-3p in HCC by directly binding the promoter of its host gene, miR17HG. Clinical data showed that a high plasma exosomal miR92a-3p level was correlated with shortened overall survival and disease-free survival, indicating poor prognosis in HCC patients. In conclusion, hepatoma-derived exosomal miR92a-3p plays a critical role in the EMT progression and promoting metastasis by inhibiting PTEN and activating Akt/Snail signaling. Exosomal miR92a-3p is a potential predictive biomarker for HCC metastasis, and this may provoke the development of novel therapeutic and preventing strategies against metastasis of HCC.