OBJECTIVE To explore the outcomes of CO2 laser assisted stapedotomy with artificial stapes prostheses in the treatment of advanced otosclerosis. METHODS Between January 2010 and January 2014, 15 patients (16 ears) diagnosed as advanced otosclerosis accepted CO2 laser assisted stapedotomy with artificial stapes implantation in our department. The averaged preoperative air conduction threshold of the speech frequency was 70.21 dB HL, the averaged bone conduction threshold was 38.49 dB HL, the averaged air-bone gap (ABG) was 31.72 dB HL. All cases were followed up for more than 6 months after operation. RESULTS All cases accepted auditory follow up after 6 months postoperatively. The speech frequency average air conduction threshold was 43.7 dB HL, the average bone conduction threshold was 28.95 dB HL, the average ABG was 14.75 dB HL. The ABG≤20 dB was achieved in 9 ears (56.3%) and ABG closure (≤10 dB) was achieved in 6 ears (37.5%). No cases appeared intractable vertigo, sensorineural hearing loss, secondary facial paralysis and other serious complications. CONCLUSION CO2 laser assisted technique reduced the probability of serious complications of stapedotomy, most patients with hearing level improved significantly. It's a safe, practical, relatively economical choice for advanced otosclerosis.

Human astrovirus (HastV) is recognized as one of the leading causes of acute viral diarrhea in infants. The HastV non-structural protein, nsPla, and C-terminal protein, nsPla/4, contain various conserved functional domains,and may play an important role in virus replication, transcription and the virus-host interactions of HastV. This study used an E. coli system to investigate the expression of nsPla and nsPla/4 proteins. Firstly,the nsPla and nsPla/4 genes of HAstV-1 were cloned into the prokaryotic expression vector,PGEX-4T-1, to build the PGEX-4T-1a and PGEX-4T-la/4 fusion protein plasmids. Then, the recombinant plasmids were transformed into Escherichia coli BL21 (DE3) and induced with isopropyl-β-D-thiogalactopyranoside (IPTG). The optimal expression conditions of the two fusion proteins were identified and then analyzed by polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting, respectively. The results showed that the pGEX-4T-la fusion protein was maximally expressed at 30 °C after 12 hours of induction with 1.0 mM IPTG. The pGEX-4T-la/4 fusion protein was maximally expressed at 20 °C after 8 hours of induction with 0.5 mM IPTG. Western blot analysis showed that the two fusion proteins specificity reacted with the anti-nsPla and anti-GST monoclonal antibodies, respectively. This study successfully obtained the HAstV non-structural protein, nsP1a, and its C-terminal protein nsP1a/4 protein using an E. coli system. This novel study lays the foundation for future research into the pathogenic mechanisms of human astrovirus and the functions of its non-structural protein.
Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Humans ; Mamastrovirus ; genetics ; metabolism ; Viral Nonstructural Proteins ; genetics ; metabolism