The study of acoustically evoked short latency negative responses in normal guinea pigs / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To compare acoustically evoked short latency negative responses (ASNR) elicited from normal and profound hearing loss guinea pig ears and to confirm their vestibular nuclei origination.</p><p><b>METHODS</b>Forty healthy guinea pigs were employed in the experiment, which were randomly divided into the control group (8 subjects, 16 ears), the masking group (16 subjects, 32 ears) and the deafened group (16 subjects, 32 ears). Air conductive white noise was chosen for masking. Masking dilemma was avoidable by an appropriate 15 dB gap between stimulus and masking sound. Both the masking group and the deafened group were further divided into ASNR group and non-ASNR group based on the presence of ASNR. Electrolytic lesion was conducted to the vestibular nuclei, followed by ABR/ASNR recording. The lesioned brainstem slices were microscopically verified.</p><p><b>RESULTS</b>In the masking group, ASNR were present in 24 ears (75.0%, 24/32) and 12 ears (46.2%, 12/26) in deafened group, showing statistically higher presence rate for masking group (χ(2)=5.07, P=0.024). There were no significant differences for the ASNR threshold and latency between the masking ASNR group and the deafened ASNR group. For the two ASNR groups, electrolytic destruction to the vestibular nuclei subsequently eliminated the ASNR. Brainstem slice proved the accurate sites of electrolytic lesion.</p><p><b>CONCLUSION</b>Moderate white noise masking prevents hearing system potential overlap without affecting vestibular system, therefore, ASNR is successfully elicited in normal guinea pigs. Both ASNRs from normal and deafened guinea pigs are of similar natures and origination from, the vestibular nuclei.</p>

Risk factors for surgical site infection of hepatobiliary and pancreatic sur-gery / 中国感染控制杂志

Objective To study the risk factors for surgical site infections (SSIs)in patients with hepatobiliary and pancreatic surgery.Methods Sixty patients who received hepatobiliary and pancreatic surgery and suffered SSIs from January 2006 to January 2010 were selected as infections group,119 patients who also received hepatobiliary and pancreatic surgery but didn’t develop infection were as control group,retrospective investigation was per-formed.Results Univariate analysis revealed the associated factors for post-operative SSIs were age,history of car-diocerebrovascular disease,history of abdominal surgery,history of smoking,preoperative anemia,abnormal pre-operative coagulation and blood sugar,pre-operative infection,use of laparoscope,incision type,duration of opera-tion,ASA score,post-operative drainage and dressing chang within 24 hours of post-operation(all P<0.05).Mult-ivariate analysis revealed that abdominal surgery history (OR95%CI:3.09 [1.21 -7.91 ]),high NISS score (OR95%CI:6.18[2.41-15.85])were risk factors of SSIs in patients with hepatobiliary and pancreatic surgery, and dressing chang within 48 hours of post-surgery were protective factor (OR95%CI:3.81 [1.56-9.34]). Conclusion History of abdominal surgery and high score of NISS are major risk factors for SSIs in patients with hepatobiliary and pancreatic surgery.To reduce the risk of SSIs,blood glucose should be actively adj usted,anemia and coagulation abnormalities should be treated;duration of operation should be shortened as far as possible,wound should be kept clean and dressing should be changed timely after surgery.

The nucleus origin of acoustically evoked short latency negative response in guinea pigs / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>This study established a model of acoustically evoked short latency negative response (ASNR) in guinea pigs. Stereotaxic coordinate guided electrolytic lesion was applied to animal brainstem nuclei, the vestibular nucleus and the cochlear nucleus, to define the neural origin of ASNR.</p><p><b>METHODS</b>Twenty four guinea pigs with normal hearing were randomly divided into the control group (8 subjects, 16 ears) and the deafened group (16 subjects, 32 ears). Each animal experienced the auditory brainstem response (ABR) test. According to the presence of ASNR, the deafened group was further divided into ASNR group and non-ASNR group. Electrolytic lesion was conducted to the vestibular nucleus and cochlear nucleus respectively, followed by ABR test. The lesion structures were verified by brainstem slice and microscope.</p><p><b>RESULTS</b>In deafened group, the ASNR was elicited in 10 ears (31.3%). The ASNR was eliminated due to the electrolytic destruction to the vestibular nucleus, but it remained unchanged after the same procedure to the cochlear nucleus.</p><p><b>CONCLUSION</b>It is clear that the ASNR is originated from the vestibular nucleus, but not the cochlear nucleus.</p>