Hengxing Zhou

Epidemiological profile of 239 traumatic spinal cord injury cases over a period of 12 years in Tianjin, China

Abstract Study design Hospital-based retrospective review. Objective To describe the epidemiological characteristics and trends of traumatic spinal cord injury in Tianjin, China. Setting Tianjin Medical University General Hospital. Methods Medical records of 239 patients with traumatic spinal cord injury admitted to a general hospital from 1998 to 2009 were reviewed. Variables included gender, age, marital status, occupation, etiology, time of injury, level, and severity of injury. Epidemiological characteristics of different countries were compared. Results Over this period, the mean age of patients with traumatic spinal cord injury was 45.4 ± 14.1 years, and the male/female ratio was 4.6:1. In all, 86.2% were married. The leading cause was fall (52.3%), followed by motor vehicle collision (36.4%). The most common injury site was the cervical spinal cord, accounting for 82.0%. Incomplete tetraplegia made up for 59.4%, followed by complete tetraplegia (22.6%). Eight patients died after operation, six of whom died from respiratory complications. Conclusion The results of this study are in accordance with that of most other developing countries; falls and motor vehicle collisions were the two leading causes, but the mean age was older. Percentage of the aged with traumatic spinal cord injury was increasing. The low-falls group tended to expand over this period. All these data indicated that the preventive programs should focus on the traffic accidents and falls, and more attention should be paid to the aged for the vulnerability to low fall.

An Experimental Novel Study: Angelica sinensis Prevents Epidural Fibrosis in Laminectomy Rats via Downregulation of Hydroxyproline, IL-6, and TGF-β1

With laminectomy being widely accepted as the treatment for lumbar disorders, epidural fibrosis (EF) is a common complication for both the patients and the surgeons alike. Currently, EF is thought to cause recurrent postoperative pain after laminectomy or after discectomy. Angelica sinensis is a traditional Chinese medicine which has shown anti-inflammatory, antifibrotic, and antiproliferative properties. The object of this study was to investigate the effects of Angelica sinensis on the prevention of post-laminectomy EF formation in a rat model. A controlled double-blinded study was conducted in sixty healthy adult Wistar rats that underwent laminectomy at the L1-L2 levels. They were divided randomly into 3 groups according to the treatment method, with 20 in each group: (1) Angelica sinensis treatment group, (2) saline treatment group, and (3) sham group (laminectomy without treatment). All rats were euthanized humanely 4 weeks after laminectomy. The hydroxyproline content, Rydell score, vimentin cells density, fibroblasts density, inflammatory cells density, and inflammatory factors expressions all suggested better results in Angelica sinensis group than the other two groups. Topical application of Angelica sinensis could inhibit fibroblasts proliferation and TGF-β1 and IL-6 expressions and prevent epidural scar adhesion in postlaminectomy rat model.

Targeting RPTPσ with lentiviral shRNA promotes neurites outgrowth of cortical neurons and improves functional recovery in a rat spinal cord contusion model.

After spinal cord injury (SCI), the rapidly upregulated chondroitin sulfate proteoglycans (CSPGs), the prominent chemical constituents and main repulsive factors of the glial scar, play an important role in the extremely limited ability to regenerate in adult mammals. Although many methods to overcome the inhibition have been tested, no successful method with clinical feasibility has been devised to date. It was recently discovered that receptor protein tyrosine phosphatase sigma (RPTPσ) is a functional receptor for CSPGs-mediated inhibition. In view of the potential clinical application of RNA interference (RNAi), here we investigated whether silencing RPTPσ via lentivirus-mediated RNA interference can promote axon regeneration and functional recovery after SCI. Neurites of primary rat cerebral cortical neurons with depleted RPTPσ exhibited a significant enhancement in elongation and crossing ability when they encountered CSPGs in vitro. A contusion model of spinal cord injury in Wistar rats (the New York University (NYU) impactor) was used for in vivo experiments. Local injection of lentivirus encoding RPTPσ shRNA at the lesion site promoted axon regeneration and synapse formation, but did not affect the scar formation. Meanwhile, in vivo functional recovery (motor and sensory) was also enhanced after RPTPσ depletion. Therefore, strategies directed at silencing RPTPσ by RNAi may prove to be a beneficial, efficient and valuable approach for the treatment of SCI.

Astrocyte transplantation for spinal cord injury: Current status and perspective

Spinal cord injury (SCI) often causes incurable neurological dysfunction because axonal regeneration in adult spinal cord is rare. Astrocytes are gradually recognized as being necessary for the regeneration after SCI as they promote axonal growth under both physiological and pathophysiological conditions. Heterogeneous populations of astrocytes have been explored for structural and functional restoration. The results range from the early variable and modest effects of immature astrocyte transplantation to the later significant, but controversial, outcomes of glial-restricted precursor (GRP)-derived astrocyte (GDA) transplantation. However, the traditional neuron-centric view and the concerns about the inhibitory roles of astrocytes after SCI, along with the sporadic studies and the lack of a comprehensive review, have led to some confusion over the usefulness of astrocytes in SCI. It is the purpose of the review to discuss the current status of astrocyte transplantation for SCI based on a dialectical view of the context-dependent manner of astrocyte behavior and the time-associated characteristics of glial scarring. Critical issues are then analyzed to reveal the potential direction of future research.

Valproic acid-mediated neuroprotection and neurogenesis after spinal cord injury: from mechanism to clinical potential.

Spinal cord injury (SCI) is difficult to treat because of secondary injury. Valproic acid (VPA) is clinically approved for mood stabilization, but also counteracts secondary damage to functionally rescue SCI in animal models by improving neuroprotection and neurogenesis via inhibition of HDAC and GSK-3. However, a comprehensive review summarizing the therapeutic benefits and mechanisms of VPA for SCI and the issues affecting clinical trials is lacking, limiting future research on VPA and impeding its translation into clinical therapy for SCI. This article presents the current status of VPA treatment for SCI, emphasizing interactions between enhanced neuroprotection and neurogenesis. Crucial issues are discussed to optimize its clinical potential as a safe and effective treatment for SCI.

In vitro characteristics of Valproic acid and all-trans-retinoic acid and their combined use in promoting neuronal differentiation while suppressing astrocytic differentiation in neural stem cells

Multipotent neural stem cells (NSCs) are currently under investigation as a candidate treatment for central nervous system (CNS) injury because of their potential to compensate for neuronal damage and to reconstruct disrupted neuronal connections. To maximize the regenerative effect of the derived neurons and to minimize the side effects of the derived astrocytes, it is necessary to regulate the fate determination of NSCs to produce more neurons and fewer astrocytes. Both valproic acid (VPA) and all-trans-retinoic acid (ATRA), two clinically established drugs, induce neuronal differentiation and facilitate neurite outgrowth at the expense of astrocytic differentiation in NSCs. However, the time-dependent activities and the long-term treatment effects of these drugs have not been explored in NSCs. More importantly, the efficacies of VPA and ATRA in neuronal promotion and astrocytic suppression remain unclear. In this study, we compare the time-dependent characteristics of VPA and ATRA in NSC differentiation and neurite outgrowth in vitro and, for the first time, demonstrate the improved efficacy of their combined application in neuronal induction and astrocytic suppression. These significant effects are closely coupled to the altered expression of a neurogenic transcription factor, a Wnt signaling component, a cell cycle regulator and a neural growth factor, indicating an underlying cross-talk between the mechanisms of action of ATRA and VPA. These findings indicate that a novel strategy combining these two therapeutic drugs may improve the restorative effect of NSC transplantation by altering the expression of their interconnected targets for fate determination.

Effectiveness of Teriparatide on Fracture Healing: A Systematic Review and Meta-Analysis.

Purpose Nowadays, the efficacy of teriparatide in treating osteoporosis was widely accepted, but the discussion about using teriparatide to enhance fracture healing hasn’t come to an agreement. This meta-analysis was conducted to evaluate the effectiveness of teriparatide for fracture healing. Methods We searched PubMed, the Cochrane Library, and Embase in August 2016 for randomized controlled trials (RCTs) which concerned the treatment of teriparatide for fracture healing. Results Finally, a total of 380 patients were randomly assigned in the 5 trials included in this meta-analysis. There was a significant effectiveness with regards to function improvement in patients following fracture, however, there was no significant effectiveness with regards to time of radiographic fracture healing, fracture healing rate and reduction in pain. Conclusions This analysis showed that administration of teriparatide following fracture lacked the effectiveness for fracture healing. Moreover, teriparatide administration had no apparent adverse effects. These results should be interpreted with caution because of some clear limitations. If we want to confirm whether teriparatide improves fracture healing, more high-quality randomized controlled trials are needed.

Cryptococcosis of lumbar vertebra in a patient with rheumatoid arthritis and scleroderma: case report and literature review

BackgroundAlthough cryptococcosis mainly occurs in the central nervous system and lungs in immunocompromised hosts, it can involve any body site or structure. Here we report the first case of primary cryptococcosis of a lumbar vertebra without involvement of the central nervous system or lungs in a relatively immunocompromised individual with rheumatoid arthritis and scleroderma.Case presentationA 40-year-old Chinese woman with rheumatoid arthritis diagnosed 1 year beforehand and with a subsequent diagnosis of scleroderma was found to have an isolated cryptococcal infection of the fourth lumbar vertebra. Her main complaints were severe low back and left leg pain. Cryptococcosis was diagnosed by CT-guided needle biopsy and microbiological confirmation; however, serum cryptococcal antigen titer was negative. After 3 months of antifungal therapy with fluconazole the patient developed symptoms and signs of scleroderma, which was confirmed on laboratory tests. After taking fluconazole for 6 months, the progressive destruction of the lumbar vertebral body had halted and the size of an adjacent paravertebral mass had decreased substantially. On discharge symptoms had resolved and at an annual follow-up there was no evidence of recurrence on the basis of symptoms, signs or imaging investigations.ConclusionAlthough cryptococcosis of the lumbar vertebra is extremely rare, it should be considered in the differential diagnosis for patients with lumbar vertebral masses to avoid missed diagnosis, misdiagnosis and diagnostic delay. Early treatment with antifungals proved to be a satisfactory alternative to surgery in this relatively immunocompromised patient. Any residual spinal instability can be treated later, once the infection has resolved.

The roles of microRNAs in spinal cord injury

ABSTRACT Background and purpose: Spinal cord injury (SCI) involves serious damage that can result in abnormal or absent motor and sensory functions and a disruption of autonomic function, and a series of pathological reactions occur after the injury. As a type of small non-coding RNA, microRNAs (miRNAs) have been verified to inhibit gene expression via post-transcriptional regulation. This review mainly focuses on recent advances regarding the roles of miRNAs following SCI. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were adopted. The studies regarding the roles of miRNAs following SCI were identified through PubMed, Embase and Web of Science. We summarise the changes in expression levels of miRNAs and discuss the roles of miRNAs after SCI. Results: A total of 77 empirical studies meeting the inclusion criteria were identified. Existing studies showed that miRNAs were temporally altered and had effects on apoptosis, inflammation, angiogenesis, astrogliosis, oligodendrocyte development, axonal regeneration and remyelination after SCI. The alteration of miRNAs and the regulative action of pathological reactions can also provide opportunities for potential therapeutic interventions. “miRNA replacement therapy” aims to transfer miRNAs into diseased cells via delivery techniques and improve targeting effectiveness in cells, and this novel therapeutic tool provides a promising technique to promote the repair of SCI and reduces functional deficits. Conclusions: This review is helpful for understanding the underlying mechanisms of SCI and the potential clinical value of miRNAs. miRNAs have the potential to be attractive tools and targets for novel diagnostic and therapeutic approaches of SCI.

Skeletal cryptococcosis from 1977 to 2013

Skeletal cryptococcosis, an aspect of disseminated cryptococcal disease or isolated skeletal cryptococcal infection, is a rare but treatable disease. However, limited information is available regarding its clinical features, treatment, and prognosis. This systematic review examined all cases published between April 1977 and May 2013 with regard to the factors associated with this disease, including patient sex, age, and epidemiological history; affected sites; clinical symptoms; underlying diseases; laboratory tests; radiological manifestations; and delays in diagnosis, treatment, follow-up assessments, and outcomes. We found that immune abnormality is a risk factor but does not predict mortality; these observations are due to recent Cryptococcus neoformans var gattii (CNVG) outbreaks (Chaturvedi and Chaturvedi, 2011). Dissemination was irrespective of immune status and required combination therapy, and dissemination carried a worse prognosis. Therefore, a database of skeletal cryptococcosis cases should be created.