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Quercetin, a flavonoid known for its antioxidant properties, has recently garnered attention as a potential neuroprotective agent for treatment of the injured nervous system. The repair of peripheral nerve injuries hinges on the proliferation and migration of Schwann cells, which play a crucial role in supporting axonal growth and myelination. In this study we synthesized Quercetin-derived carbon dots (QCDs) and investigated their effects on cultured Schwann cells and the NG108-15 cell line. QCDs was obtained by solvothermal synthesis and characterized via UV–vis absorption spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction analysis. The particles demonstrated significant dose-dependent free radical scavenging activity in DPPH and ABTS radical scavenging assays, supported in vitro proliferation and migration of Schwann cells, expression of neurotrophic and angiogenic growth factors, and stimulated neurite outgrowth from NG108-15 cells. Thus, QCDs could serve as a potential novel treatment strategy to promote regeneration in the injured peripheral nervous system.

Background: A brachial plexus birth injury (BPBI) can cause reduced ability to use the arm and hand in daily activities due to reduced grip strength and endurance. A soft robotic glove can increase the number of activities performed and improve activity performance for patients with neurological disease. The use of a soft robotic glove for patients with BPBI has not been studied.

Purpose: To investigate if a soft robotic glove can improve activity performance and body function for patients with BPBI.

Study design: Longitudinal Case Series.

Methods: A convenience sample of patients with BPBI, treated by the Brachial plexus injury service in Umeå, Sweden were studied. Eight patients used a soft robotic glove, (Carbonhand®), at home for three months. Data on activity performance and satisfaction with activity performance, active range of motion and strength were collected at baseline, and at three and four months. A patient evaluation form was filled out at three months, all patients kept a diary for three out of 12 weeks.

Results: Six out of eight patients wanted to continue using the device and improved their self-perception of activity performance and satisfaction with the performance due to a more secure grip, compared to when not using the device. All patients had improved maximum strength and endurance in elbow flexion at three months. The device was useful as an assisting device and as a training tool.

Conclusion: A soft robotic glove (Carbonhand) may improve activity performance and perceived satisfaction and increase the number of activities that a person with BPBI can perform in everyday life. It is possible to increase strength in elbow flexion after using such a device. Due to this limited material, more research is needed.

The present study analyses the relationships between deprivation and obstetric brachial plexus palsy (OBPP). A retrospective observational study was conducted of infants with OBPP seen between 2008 and 2020 (n = 321). The index of multiple deprivation (IMD) was used to assign an IMD rank to patients based on birth postcode and the relationship with OBPP was analysed, including deprivation, gestational diabetes, age at referral and at first assessment. Quintile-based analysis demonstrated over-representation of patients from more deprived neighbourhoods (n = 109, 39%) living in the top 20% most deprived neighbourhoods. A total of 48 (15%) mothers had diabetes and 98 (31%) infants underwent surgical brachial plexus exploration (a marker of disease severity). Neither diabetes, age at referral nor age at first assessment were associated with IMD score. This suggests that neighbourhood deprivation is associated with OBPP, though the mechanisms are unclear. Further studies in this area may enable targeted health intervention for more deprived maternal and infant groups.

Introduction: Before performing cell therapy clinical trials, it is important to understand how cells are influenced by different growth conditions and to find optimal xeno-free medium formulations. In this study we have investigated the properties of adipose tissue-derived stem cells (ASCs) cultured under xeno-free conditions.

Methods: Human lipoaspirate samples were digested to yield the stromal vascular fraction cells which were then seeded in i) Minimum Essential Medium-α (MEM-α) supplemented with 10 % (v/v) fetal bovine serum (FBS), ii) MEM-α supplemented with 2 % (v/v) human platelet lysate (PLT) or iii) PRIME-XV MSC expansion XSFM xeno-free, serum free medium (XV). Flow cytometry for ASCs markers CD73, CD90 and CD105 together with the putative pericyte marker CD146 was performed. Growth rates were monitored over multiple passages and adipogenic differentiation performed at early and expanded passage culture. Growth factor gene expression was analyzed and an in vitro angiogenesis assay performed.

Results: Cells in FBS and PLT grew at similar rates whereas the cells cultured in XV medium proliferated significantly faster up to 60 days in culture. All cultures were >98 % positive for CD73, CD90 and CD105, whereas CD146 expression was significantly higher in XV cells. Adipogenic differentiation was most pronounced in cells which had been cultured in XV medium whilst cells grown in PLT were inferior compared with cells from the FBS cultures. IGF1 gene expression was highest in cells cultured in PLT whilst cells grown in XV medium showed 10-fold lower expression compared with FBS cells. In contrast, HGF gene expression was 90-fold greater in cells cultured in XV medium compared with those cultured in FBS. Conditioned medium from XV cultured cells showed the most angiogenic activity, inducing the greatest endothelial cell network formation and maturation.

Conclusion: Culture under different conditions alters the ASCs characteristics. Since cells cultured in XV medium showed the best adipogenic and angiogenic profile this might be a preferred medium formulation for preparing cells required for reconstructive surgical applications such as cell-assisted fat grafting.

Background: The use of mesenchymal stem cells (MSCs) for the development of tissue-engineered constructs has advanced in recent years. However, future clinically approved products require following good manufacturing practice (GMP) guidelines. This includes using alternatives to xenogeneic-derived cell culture supplements to avoid rejection of the transplants. Consequently, human platelet lysate (PLT) has been adopted as an affordable and effective alternative to foetal bovine serum (FBS) in traditional 2D cultures. However, little is known about its effect in more advanced 3D culture systems.

Methods: We evaluated bone marrow MSCs (BMSCs) proliferation and CD marker expression in cells expanded in FBS or PLT-supplemented media. Differentiation capacity of the BMSCs expanded in the presence of the different supplements was evaluated in 3D type I collagen hydrogels. Furthermore, the effects of the supplements on the process of differentiation were analyzed by using qPCR and histological staining.

Results: Cell proliferation was greater in PLT-supplemented media versus FBS. BMSCs expanded in PLT showed similar osteogenic differentiation capacity in 3D compared with FBS expanded cells. In contrast, when cells were 3D differentiated in PLT they showed lower osteogenesis versus the traditional FBS protocol. This was also the case for adipogenic differentiation, in which FBS supplementation was superior to PLT.

Conclusions: PLT is a superior alternative to FBS for the expansion of MSCs without compromising their subsequent differentiation capacity in 3D. However, differentiation in PLT is impaired. Thus, PLT can be used to reduce the time required to expand the necessary cell numbers for development of 3D tissue engineered MSC constructs.

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess and compare the effects and complication rates of licensed bioengineered nerve conduits or wraps for surgical repair of traumatic peripheral nerve injuries of the upper limb. To compare effects and complications against the current gold surgical standard (nerve autograft).

Injuries to large peripheral nerves are often associated with tissue defects and require reconstruction using autologous nerve grafts, which have limited availability and result in donor site morbidity. Peripheral nerve-derived hydrogels could potentially supplement or even replace these grafts. In this study, three decellularization protocols based on the ionic detergents sodium dodecyl sulfate (P1) and sodium deoxycholate (P2), or the organic solvent tri-n-butyl phosphate (P3), were used to prepare hydrogels. All protocols resulted in significantly decreased amounts of genomic DNA, but the P2 hydrogel showed the best preservation of extracellular matrix proteins, cytokines, and chemokines, and reduced levels of sulfated glycosaminoglycans. In vitro P1 and P2 hydrogels supported Schwann cell viability, secretion of VEGF, and neurite outgrowth. Surgical repair of a 10 mm-long rat sciatic nerve gap was performed by implantation of tubular polycaprolactone conduits filled with hydrogels followed by analyses using diffusion tensor imaging and immunostaining for neuronal and glial markers. The results demonstrated that the P2 hydrogel considerably increased the number of axons and the distance of regeneration into the distal nerve stump. In summary, the method used to decellularize nerve tissue affects the efficacy of the resulting hydrogels to support regeneration after nerve injury.

Background: Peripheral nerve injuries represent a clinical challenge, especially when they are accompanied by loss of neural tissue. In this study, the authors attempted to attain a better outcome after a peripheral nerve injury by both repairing the nerve lesion and treating the denervated muscle at the same time.

Methods: Rat sciatic nerves were transected to create 10-mm gaps. Repair was performed in five groups (n = 5 rats for each), as follows: group 1, nerve repair using poly-3-hydroxybutyrate strips to connect the proximal and distal stumps, in combination with control growth medium injection in the gastrocnemius muscle; group 2, nerve repair with poly-3-hydroxybutyrate strip seeded with Schwann cell-like differentiated adipose stem cells (differentiated adipose stem cell strip) in combination with growth medium intramuscular injection; group 3, differentiated adipose stem cell strip in combination with intramuscular injection of differentiated adipose stem cells; group 4, repair using autograft (reverse sciatic nerve graft) in combination with intramuscular injection of growth medium; and group 5, autograft in combination with intramuscular injection of differentiated adipose stem cells. Six weeks after nerve injury, the effects of the stem cells on muscle atrophy were assessed.

Results: Poly-3-hydroxybutyrate strips seeded with differentiated adipose stem cells showed a high number of βIII-tubulin-positive axons entering the distal stump and abundant endothelial cells. Group 1 animals exhibited more muscle atrophy than all the other groups, and group 5 animals had the greatest muscle weights and muscle fibers size.

Conclusion: Bioengineering nerve repair in combination with intramuscular stem cell injection is a promising technique to treat nerve lesions and associated muscle atrophy. Clinical Relevance Statement: Nerve injuries and resulting muscle atrophy are a clinical challenge. To optimize functional recovery after a nerve lesion, the authors treated the nerve and muscle at the same time by using regenerative medicine with adipose stem cells and obtained encouraging results for future clinical applications.

Diffusion tensor imaging (DTI) metrics, such as the fractional anisotropy (FA) and estimates of diffusivity are sensitive to the microstructure of peripheral nerves and may be displayed as tractograms. However, the ideal conditions for tractography of the roots of the brachial plexus are unclear, which represents the rationale for this study. Ten healthy adults were scanned using a Siemens Prisma (3T) and single-shot echo-planar imaging (b-value 0/1000 s/mm2, 64 directions, 2.5 mm3 with 4 averages; repeated in opposing phase encoding directions). Susceptibility correction and tractography were performed in DSI Studio by two independent raters. The effect of FA thresholding at increments of 0.01 (from 0.04 to 0.10) were tested. The mean FA varied between subjects by 2% (95% CI 1%, 3%). FA thresholds of 0.04, 0.05 and 0.06 all propagated 96% of tracts representing the roots; thresholding at 0.07 yielded 4% fewer tracts (p = 0.2), 0.08 yielded 11% fewer tracts (p = 0.008), 0.09 yielded 15% fewer tracts (p = 0.001) and 0.1 yielded 20% fewer tracts (p < 0.001). There was < 0.1% inter-rater variability in the measured FA and 99% agreement for tractography (κ = 0.92, p < 0.001). The fractional anisotropy thresholds required to generate tractograms of the roots of the brachial plexus appears to be lower than those used in the brain. We provide estimates of the probability of generating true tracts for each spinal nerve root of the brachial plexus, at different fractional anisotropy thresholds.

Spinal cord injury results in irreversible tissue damage and permanent sensorimotor impairment. The development of novel therapeutic strategies that improve the life quality of affected individuals is therefore of paramount importance. Cell transplantation is a promising approach for spinal cord injury treatment and the present study assesses the efficacy of human embryonic stem cell-derived neural crest cells as preclinical cell-based therapy candidates. The differentiated neural crest cells exhibited characteristic molecular signatures and produced a range of biologically active trophic factors that stimulated in vitro neurite outgrowth of rat primary dorsal root ganglia neurons. Transplantation of the neural crest cells into both acute and chronic rat cervical spinal cord injury models promoted remodeling of descending raphespinal projections and contributed to the partial recovery of forelimb motor function. The results achieved in this proof-of-concept study demonstrates that human embryonic stem cell-derived neural crest cells warrant further investigation as cell-based therapy candidates for the treatment of spinal cord injury.