A coaxially extruded heterogeneous core-shell fiber with Schwann cells and neural stem cells

Cellular therapies play a critical role in the treatment of spinal cord injury(SCI).Compared with cell-seeded conduits,fully cellular grafts have more similarities with autografts,and thus might result in better regeneration effects.In this study,we fabricated Schwann cell(SC)-neural stem cell(NSC)core–shell alginate hydrogel fibers in a coaxial extrusion manner.The rat SC line RSC96 and mouse NSC line NE-4C were used in this experiment.Fully cellular components were achieved in the core portion and the relative spatial positions of these two cells partially mimic the construction of nerve fibers in vivo.SCs were demonstrated to express more genes of neurotrophic factors in alginate shell.Enhanced proliferation and differentiation tendency of NSCs was observed when they were co-cultured with SCs.This model has strong potential for application in SCI repair.

Three-dimensional printing technology for treatment of intracranial aneurysm

Background:The development of three-dimensional (3D) printing technology provides a new method for surgical treatment,but currently there are few reports on its application in the treatment of aneurysm.The aim of the present study was to explore the materials and methods of fabricating 3D printed individual aneurysm model and its value in the treatment of intracranial aneurysm.Methods:Twenty-four patients with intracranial aneurysm diagnosed by CTA who had undergone operation in our hospital were analyzed retrospectively.CTA Data collected at the time of surgery was used for reconstruction.Soft Mimics 17.0 was used to reconstruct the thin layer CTA scan data into 3D image and the final data was sent to the 3D printer for fabricating the model.We compared the proposed 3D printed model-based preoperative plan and the actual approach used in the surgery based on CTA data to evaluate the value of the 3D printed model in preoperative planning,and picked out the materials which were more suitable for the clinic.Results:Twenty-four aneurysm models with high degree of reality were fabricated successfully with 3D-printing technology.The patients' blood vessels,skulls and aneurysms were printed into the reality model at a ratio of 1:1.It is reported that the soft material-based,3D printed vascular and aneurysm model more closely resembled the characteristics of the real blood vessels,thus provides a better simulation compared to the plaster-based model.Compared with the original operation plan,3D printed model could be used for pre-operative aneurysm clip selection,and provide more intuitive information in selection of operational approach.Conclusions:3D printed model can be used as an operational physical model to design operative schemes,choose the best operative paths and select suitable aneurysm clips by its high simulation degree and individualized characteristics.The model is helpful for surgical planning,especially for the preoperative plan of treating refractory multiple aneurysms and giant aneurysms.

Electrospun poly(L-lactic acid)/gelatine membranes loaded with doxorubicin for effective suppression of glioblastoma cell growth in vitro and in vivo

Electrospun membranes are attracting interest as a drug delivery system because of their material composition flexibility and versatile drug loading.In this study,the electrospun membrane was loaded with doxorubicin(DOX)via electrostatic adsorption for long-term drug delivery.DOX loading process was optimized by varying temperature,time,drug concentration,pH and ionic strength of solutions.The loading process did not impair the structural properties of the membrane.Next,we investigated the drug release kinetics using spectroscopic techniques.The composite membranes released 22%of the adsorbed DOX over the first 48 h,followed by a slower and sustained release over 4 weeks.The DOX release was sensitive to acidic solutions that the release rate at pH 6.0 was 1.27 times as that at pH 7.4.The DOX-loaded membranes were found to be cytotoxic to U-87 MG cells in vitro that decreased the cell viability from 82.92%to 25.49%from 24 to 72 h of coincubation.These membranes showed strong efficacy in suppressing tumour growth in vivo in glioblastoma-bearing mice that decreased the tumour volume by 77.33%compared with blank membrane-treated group on Day 20.In conclusion,we have developed an effective approach to load DOX within a clinically approved poly(L-lactic acid)/gelatine membrane for local and longterm delivery of DOX for the treatment of glioblastoma.