GENETIC ENGINEERING NEURAL STEM CELL MODIFIED BY LENTIVIRUS FOR REPAIR OF SPINAL CORD INJURY IN RATS

Objective To explore the feasibility for therapy of spinal cord injury (SCI) by genetic engineering neural stem cell (NSC) modified by lentiviral vector. Methods Following the construction of the genetic engineering NSC modified by lentivirus to secrete both neurotrophic factor-3 (NT-3) and green fluorescence protein (GFP), hemisection of spinal cord at the level of T_ 10 was performed in 56 adult Wistar rats that were randomly divided into 4 groups (n=14), namely 3 therapeutic groups and 1 control group. The therapeutic groups were dealed with NSC, genetic engineering NSC, and concentrated lentiviral supernatant which carries both GFP and NT-3, respectively. Then used fluorescence microscope to detect the transgenic expression in vitro and in vivo, migration of the grafted cells in vivo, and used the Basso, Beattie, and Bresnahan (BBB) open-field locomotor test to assess the recovery of function. Results The transplanted cells could survive for long time in vivo and migrate for long distance. The stable transgenic expression could be detected in vivo. The hindlimb function of the injured rats in 3 therapeutic groups, especially those dealed with genetic engineering NSC, improved obviously. Conclusion It is feasible to combine NSC with lentivirus for the repair of SCI. NSC modified by lentivirus to deliver NT-3, acting as a source of neurotrophic factors and function cell in vivo, has the potential to participate in spinal cord repair.

Hypertrophic adenoids in patients with nasopharyngeal carcinoma:appearance at magnetic resonance imaging before and after treatment

Introduction:Patients with nasopharyngeal carcinoma(NPC) sporadically develop abnormal adenoids.Nasopharyngeal adenoids are usually included in the gross tumor volume(GTV) but may have different therapeutic responses than tumor tissue.Therefore,distinguishing adenoids from tumor tissue may be required for precise and efficient chemoradiotherapy and radiotherapy.We characterized nasopharyngeal adenoids and investigated the therapeutic responses of NPC and nasopharyngeal adenoids using magnetic resonance imaging(MRI).Methods:MRI data from 40 NPC patients with a coexisting adenoid mass before and after treatment were analyzed.The features of the adenoid masses,including location,striped appearance,size,interface,symmetry/asymmetry,and cysts,were evaluated.Treatment response were scored according to the World Health Organization guidelines.Results:A striped appearance was observed in 36 cases before treatment and in all cases after treatment.In these 36 cases,the average GTVs including and excluding the uninvolved adenoids were 19.8 cm^3 and 14.8 cm^3,respectively.The average percentage change after excluding the uninvolved adenoids from the GTV was 31.0%.Stable disease in the adenoids was identified in 27(96.4%) of 28 patients after neoadjuvant chemotherapy,while NPC clearly regressed.Partial adenoid responses were identified in 33(82.5%) of 40 patients at 3 months after chemoradiotherapy or radiotherapy,whereas complete tumor responses were achieved in all patients.Six months after treatment,the adenoids continued to atrophy but did not disappear,and tumor recurrence was not found.Conclusions:Nasopharyngeal adenoids and carcinoma tissue in NPC patients can be distinguished by using MRI and have different responses to chemoradiotherapy and radiotherapy.These findings contribute to better delineating the GTV of NPC,based on which spatially optimized strategies can be developed to render precise and efficient chemoradiotherapy and radiotherapy.Additionally,we observed a clear difference in the responses of these two tissue types to current therapies.This finding may reduce or avoid unnecessary biopsies or overtreatment.