Histological and functional outcomes in a rat model of hemisected spinal cord with sustained VEGF/NT-3 release from tissue-engineered grafts.

Microvascular disturbance, excessive inflammation and gliosis are key pathophysiologic changes in relation to functional status following the traumatic spinal cord injury (SCI). Continuous release of vascular endothelial growth factor (VEGF) to the lesion site was proved be able to promote the vascular remodelling, whereas the effects on reduction of inflammation and gliosis remain unclear. Currently, aiming at exploring the synergistic roles of VEGF and neurotrophin-3 (NT-3) on angiogenesis, anti-inflammation and neural repair, we developed a technique to co-deliver VEGF and NT-3 locally with a homotopic graft of tissue-engineered acellular spinal cord scaffold (ASCS) in a hemisected (3 mm in length) SCI model.

Dorsal root ganglion axons facilitate and guide cortical neural outgrowth: In vitro modeling of spinal cord injury axonal regeneration.

Background: Spinal cord injury (SCI) patients represent a heterogeneous group, with injuries ranging from partial compression to complete transection. Patients with complete injuries are unlikely to exhibit recovery and suffer from paralysis as well as the loss of bowel and bladder function. One treatment option is the formation of a bridge through a lesion site, whereby transplanted cells or biocompatible scaffolds guide the regenerating axons across the site of injury.

Transplantation of a Peripheral Nerve with Neural Stem Cells Plus Lithium Chloride Injection Promote the Recovery of Rat Spinal Cord Injury.

Transplantation of neural stem cells (NSCs) holds great potential for the treatment of spinal cord injury (SCI). However, transplanted NSCs poorly survive in the SCI environment. We injected NSCs into tibial nerve and transplanted tibial nerve into a hemisected spinal cord and investigated the effects of lithium chloride (LiCl) on the survival of spinal neurons, axonal regeneration, and functional recovery.

Acellular Spinal Cord Scaffold Implantation Promotes Vascular Remodeling with Sustained Delivery of VEGF in a Rat Spinal Cord Hemisection Model.

Background: Promoting angiogenesis provides a possible therapeutic approach in treating spinal cord injury (SCI). Vascular endothelial growth factor (VEGF) is a pro-angiogenic substance that is involved in endothelial cell (EC) proliferation, migration, and survival. Exogenous administration of VEGF to the lesion epicenter of the spinal cord has been recently revealed as a potential method for promoting the blood vessel sprouting.

Effect of melatonin on the proliferation and differentiation of chondrocytes from rat vertebral body growth plate in vitro.

Purpose: Abnormal growth of vertebral body growth plate (VBGP) is considered as one of the etiologic factors in the adolescent idiopathic scoliosis (AIS). It was well-known that melatonin was correlated with the emergence and development of AIS. This study aimed to investigate the effect of melatonin on rat VBGP chondrocytes in vitro.

Repair of critical size bone defects with porous poly(D,L-lactide)/nacre nanocomposite hollow scaffold.

Objective: To generate a novel porous poly(D,L-lactide)/nacre nanocomposite hollow scaffold.

Methods: This study was performed in the Department of Spine Surgery, Southern Medical University, Guangzhou, China from September 2010 to September 2011. Nacre nanoparticles were prepared using a physical process and identified by x-ray diffraction and transmission electron microscopy, to generate a novel scaffold though the salt leaching processing technique.

Amide-linkage formed between ammonia plasma treated poly(D,L-lactide acid) scaffolds and bio-peptides: enhancement of cell adhesion and osteogenic differentiation in vitro.

The surface characteristics of scaffolds for bone tissue engineering must support cell adhesion, migration, proliferation, and osteogenic differentiation. In the study, poly(D,L-lactide acid) (PDLLA) scaffolds were modified by combing ammonia (NH(3) ) plasma pretreatment with Gly-Arg-Gly-Asp-Ser (GRGDS)-peptides coupling technologies. The x-ray photoelectron spectroscopy (XPS) survey spectra showed the peak of N1s at the surface of NH(3) plasma pretreated PDLLA, which was further raised after GRGDS conjugation.

[Histology and proliferative capability of thoracic vertebral body growth plates of rats at different ages].

Objective: To compare the histological features of the thoracic vertebral body growth plates (VBGPs) of rats at different ages and assess their proliferative capability.

Methods: The thoracic VBGPs obtained from rats aged 1 day and 1, 4, 8, 16 and 28 weeks were identified using safranin O-fast green staining, and the height of the hypertrophic zone, proliferative zone, and resting zone were measured. The chondrocytes were isolated from these VBGPs with a modified trypsin-collagenase type II digestion method for primary culture in vitro.

[Effects of bioactive modification of poly-D,L-lactide acid scaffolds on the biological behaviors of the seed cells].

Objective: To study the changes in the biological behavior of bone marrow mesenchymal stem cells (BMSCs) transfected with red fluorescent protein by lentivirus (RFP-BMSCs) seeded on in poly-D, L-lactide acid (PDLLA) scaffolds with bioactive modification by ammonia plasma and Gly-Arg-Gly-Asp-Ser (GRGDS) in vitro.

Methods: Circular sheets of PDLLA scaffolds (8 mm in diameter and 1 mm in thickness) were prepared and aminated with PDLLA (group A) or modified with the peptide conjugate A/PDLLA (group PA), with untreated PDLLA as the control (group P). The RFP-BMSCs were seeded on the scaffold materials and their proliferation and metabolic activity were detected using CyQuant NF and Alamar blue staining.

Does whole-body vibration with alternative tilting increase bone mineral density and change bone metabolism in senior people?

Background And Aims: Whole-body vibration (WBV) presents as osteogenic in animal models and young patients, but the effect remains unclear in senior people. The use of alternative tilting during WBV to ameliorate bone mass and bone metabolism, particularly in senior people, has not previously been reported. This study assessed changes in bone mineral density (BMD) and bone metabolism in senior people after six-month treatment of whole-body vibration with alternative tilting (WBVAT).

Growth/differentiation factor-5 induces osteogenic differentiation of human ligamentum flavum cells through activation of ERK1/2 and p38 MAPK.

Ossification of ligamentum flavum (OLF) is a pathological ectopic ossification in the spinal ligament, leading to spinal canal stenosis, but little was known about its pathogenesis. A previous study has found growth/differentiation factor (GDF)-5 expression at ossified sites of the ligaments from OLF patients. This study aimed to investigate the osteogenic effects of GDF-5 on cultured human ligamentum flavum cells (LFCs).

[Experimental study of reservation flaval ligament on prevention of peridural adhesion after operation on lumbar disc].

Objective: Through an experiment in rabbits, to evaluate the role of reservation flaval ligament using different methods to prevent the epidural adhesion by observing the morphological changes and provide experiment evidences for clinic.

Methods: 45 adult rabbits were divided into three groups: Group A (treated with no reservation of flaval ligament), Group B (treated with reserving half flaval ligament), and Group C (treated with reserving the complete flaval ligament). Every group has 15 rabbits.

[Prevention of dura adherence in spinal canal after microendoscopic discectomy by different methods: a clinical study of 165 cases].

Objective: To evaluate the effects of different methods in prevention of post-operational scar formation and dura adherence in the spinal canal after microendoscopic discectomy (MED).

Methods: 165 patients undergoing MED were randomly divided into 3 equal groups: Group A, with the yellow ligament dissected and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision; Group B, with the yellow ligament reserved; and Group C, with the yellow ligament reserved and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision. All the patients were followed up 2, 4, and 8 weeks, and 1 and 2 years after the operation.