[Effect of cycloxygenase 2 inhibitor on levels of prostaglandin E2 in plasma and in local infiltrated fluid after functional endoscopic sinus surgery].

OBJECTIVE: To examine the time course and clinical relevance of changes in prostaglandin E2 (PGE2) to pain and outcome in surgical drainage, and circulating blood after functional endoscopic sinus surgery (FESS). METHODS: Thirty-seven patients scheduled to undergo FESS were randomized to receive celecoxib 400 mg(n=16) one hour before anesthesia induction and celecoxib 200 mg, q12 h for five consecutive days after surgery or nothing for patients in control group(n=21). Surgical site drainage and venous blood were collected up to 48 hours after surgery to test PGE2 level. Plasma levels of thromboxane A2 (TXA2) and prostacyclin (PGI2) were also tested for the same time course. RESULTS: For control patients, PGE2 level was elevated in both surgical site and circulating blood, which reached a peak concentration 6 h(177.5 ± 142.2 ng/L) and 48 h (64.5 ± 21.4 ng/L)respectively after FESS. For patients in celecoxib group, a significant reduction of surgical drainage PGE2(peak level 106.2 ± 33.4 ng/L at 6 h) and plasma PGE2 (peak level 44.7 ± 30.2 ng/L at 48 h) was observed(P<0.05). Pain scores 6 h and 48 h after surgery were positively correlated with surgical drainage PGE2 level, correlation coefficient being 0.333 (P=0.044) and 0.353(P=0.032) respectively. Celecoxib did not affect the ratio of plasma TXA2 to PGI2. CONCLUSION: Upregulation of PGE2 in surgical site after surgery was crucial in inflammatory response and postoperative pain. Cycloxygenase-2 inhibitor could significantly reduce surgical drainage and plasma PGE2 concentration.

[Development of vestibular system in children with/without attention deficit hyperactivity disorder].

OBJECTIVE: To investigate the development of vestibular system function in 7 to 14 years old normal boys and the ADHD boys; METHODS: The present study involved two groups of subjects: 148 ADHD boys (age range 7 years to 14 years) diagnosed with DSM-IV diagnostic criteria and 148 normal boys with the same age. Each group was divided into 4 clusters according to two years gap. All subjects were tested for the vestibular system function by the Vestibular Function Test System 2000/ ENG-V600 with the eye movement index. RESULTS: From 7 to 14 years, the development of vestibular system function in normal boys had the characters as the description below. The optokinetic system function exhibited more development from seven years in the normal group. From 7 to 10 years, the time delay of saccade and anti-saccade in normal boys was significantly shorter(In the normal controls , the delay time of left saccade was 149+/-66 ms in 7-8 years old boys, 108+/-64 ms in 9-10 years old boys, 117+/-72 ms in 9-10 years old boys, the delay time of left anti-saccade was 178+/-127 ms in 7-8 years old boys, 101+/-88 ms in 9-10 years old boys,P<0.05). The velocity of saccade was faster significantly(right saccade velocity was 138+/-11 degrees /s in 7-8 years old boys, 147+/-15 degrees /s in 9-10 years old boys, P<0.05). From 9 to 12 years, the velocity of anti-saccade in normal boys was significantly faster(left anti-saccade velocity was 155+/-26 degrees /s in 9-10 years old boys, 172+/-34 degrees /s in 11-12 years old P<0.05 and their accuracy of saccade enhanced(left saccade accuracy was 0.88 in 9-10 years old boys, 0.90 in 11-12 years old boys,P<0.05) . From 13 to 14 years, time delay was much shorter than before(the delay time of left saccade was 101+/-62 ms in 11-12 years old boys, 76+/-63 ms in 13-14 years old boys, P<0.05). But in ADHD group, there was the different development tendency. Their time delay shorten only in 7 to 10 years old boys(In ADHD group, the delay time of left saccade was 179.03+/-66.69 ms in 7-8 years old boys, 138+/-76 ms in 9-10 years old boys,P<0.05). And at other age, the vestibular function of ADHD boys appeared to have no significant change. The velocity of optokinetic nystagmus in 7 to 14 years old ADHD boys was slower than that of the same age in normal controls(the velocity of OKN slow phase was 138.07 degrees /s in 7-8 years old boys, 40.24 degrees /s in 9-10 years old boys and 41.30 degrees /s in 13-14 years old boys ; the velocity of OKN fast phase was 226.88 degrees /s in 11-12 years old boys. In the same conditions, the velocity of OKN slow phase was 179.03 degrees /s in 7- 8 years old boys, 43.86 degrees /s in 9-10 years old boys and 47.32 degrees /s in 13-14 years old boys; the velocity of OKN fast phase was 262.92 degrees /s in 11-12 years old boys, P<0.05). The ratio of max slow phase velocity of VVOR/OKN+VOR of 7-8 years old and 11-12 years old ADHD boys were significantly larger than those of the normal controls(left VVOR/OKN+VOR of ADHD group was 0.73 in 7-8 years old, in normal controls this ratio was 0.66; in ADHD group of 11- 12 years old, left ratio was 0.80, in normal controls this ratio was 0.71. P<0.05) . CONCLUSION: Saccade, antisaccade and visual-vestibular interaction system are developing in 7 to 14 years old normal boys, while the optokinetic nystagmus is stable. Vestibuloocular system is stable also. The development of optokinetic system and visual-vestibular interaction system in 7 to 14 years old ADHD boys delays that of the same age normal boys. Most significant differences between ADHD boys and normal boys can be seen in 11 to 12 years old boys.

[Effects of centrifuge training on mRNA expression in different rat tissues].

OBJECTIVE: To demonstrate the tissue specific expression of five rat genes related to centrifuge training and the relationship between expression change and duration of training. METHOD: mRNA was extracted from hearts, brains, kidneys, lungs and intestines of rats after different durations of training. Five genes obtained by SSH from centrifuge-trained rats were labeled by Dig-11-dUTP as probes. The expression levels were measured by thin-line hybridization. Optical density (OD) values were obtained by scanning and treated with statistics. RESULT: As compared with control group, the new gene CH157 expression decreased in hearts and brains of rats trained for 6 d (P<0.05), but returned to control levels after 12 d training; the new gene CH244 expression depressed in rat hearts, brains, and intestines after 6 d or 12 d training, but it was not statistically significant owing to large individual differences; gene expression of protein inhibitor of neuronal nitric oxide syntheses (PIN) increased gradually and significantly in rat hearts (P<0.01 after 12 d training) and kidneys (P<0.05 after 12 d training); Cyt b gene expression in rat hearts and brains increased increasingly (P<0.01 after 12 d training), however, it increased obviously (P<0.05) in kidneys, lungs and intestines of rats trained for 6 d, while it returned back a little in rats trained for 12 d; enlongation factor 1-alpha expression levels in intestines of rats trained for 6 d increased significantly (P<0.05), but it became no significant in rats trained for 12 d, while the expression in brains increased gradually (P<0.01). CONCLUSION: It suggested that the change in gene expression in several tissues of rats caused by centrifuge training contribute in enhancing +Gz tolerance.

[High Gy induced vestibular disorders in guinea pigs and its countermeasure by preconditioning].

OBJECTIVE: To explore if high G exposure can cause vestibular disorder in guinea pig and the possibility of preventing it by preconditioning with exposure to a low hypergravity environment before high G stimulus. METHOD: A total of 86 guinea pigs were divided into 4 groups: 1) 28 were treated with a stimulus of +10 Gy for 5 min (+10 Gy group); 2) 28 were preconditioned by exposure to 2 G environment for 8 d before the +10 Gy stimulus (preconditioning group); 3) 20 were exposed to 2 G environment for 8 d, but without +10 Gy stimulus (2 G group); the rest 10 served as control. Their vestibular related behaviour, including vestibulo-spinal reflex (VSR) and vestibulo-ocular reflex (VOR) such as head tremble, head deviation, spontaneous nystagmus, eye deviation, body tilt or looping, were observed directly, the choline acetyltransferase (ChAT) activity in VNC (vestibular nucleon complex) in brain stem were investigated by immunohistochemistry technique, and the relative gamma in each group were analysed. RESULT: The incidence of behavioral abnormalities (BA) in 10 Gy group (79%) is significantly higher than that in preconditioning group (50%). The relative gamma of staining showed that the content of ChAT in VNC of the +10 Gy group and preconditioning group were significantly higher than that in control group, but no difference was found between them in +10 Gy and preconditioning groups. CONCLUSION: High G exposure of +10 Gy for 5 min could cause vestibular disorders in guinea pigs, and preconditioning with pre-exposure to 2 G environment could alleviate it. ChAT activity changes in VNC may contribute to its mechanisms.