Gene transfer into primary cultures of fetal neural stem cells by a recombinant adenovirus carrying the gene for green fluorescent protein

Objective: To evaluate the transduction efficiency of a recombinant adenovirus carrying the gene for green fluorescent protein (Ad-GFP) into the primary cultures of fetal neural stem cells (NSCs) by the expression of GFP. Methods: The Ad-GFP was constructed by homologous recombination in bacteria with the AdEasy system; NSCs were isolated from rat fetal hippocampus and cultured as neurosphere suspensions. After infection with the recombinant Ad-GFP, NSCs were examined with a fluorescent microscopy and a flow cytometry for their expression of GFP. Results: After the viral infection, flow cytometry analysis revealed that the percentage of GFP-positive cells was as high as 97.05%. The infected NSCs sustained the GFP expression for above 4 weeks. After differentiated into astrocytes or neurons, they continued to express GFP efficiently. Conclusion: We have success- fully constructed a viral vector Ad-GFP that can efficiently infect the primary NSCs. The reporter gene was showed fully and sustained expression in the infected cells as well as their differentiated progenies.

Genetic Effects on Sensorineural Hearing Loss and Evidence-based Treatment for Sensorineural Hearing Loss

In this article,the mechanism of inheritance behind inherited hearing loss and genetic susceptibilityin noise-induced hearing loss are reviewed.Conventional treatments for sensorineural hearing loss(SNHL),i.e.hearing aid and cochlear implant,are effective for some cases,but not without limitations.For example,they provide little benefit for patients of profound SNHL or neural hearing loss,especially when the hearing loss is in poor dynamic range and with low frequency resolution.We emphasize the most recent evidence-based treatment in this field,which includes gene therapy and allotransplantation of stem cells.Their promising results have shown that they might be options of treatment for profound SNHL and neural hearing loss.Although some treatments are still at the experimental stage,it is helpful to be aware of the novel therapies and endeavour to explore the feasibility of their clinical application.

Confounding Effect in Clinical Research of Otolaryngology and Its Control

Confounding effect is a critical issue in clinical research of otolaryngology because it can distort the research's conclusion. In this review, we introduce the definition of confounding effect, the methods of verifying and controlling the effect. Confounding effect can be prevented by research's design, and adjusted by data analysis. Clinicians would be aware and cautious about confounding effect in their research. They would be able to set up a research's design in which appropriate methods have been applied to prevent this effect.They would know how to adjust confounding effect after data collection. It is important to remember that sometimes it is impossible to eliminate confounding effect completely, and statistical method is not a master key. Solid research knowledge and critical thinking of our brain are the most important in controlling confounding effect.