AIM: To establish a simple, rapid and accurate high performance liquid chromatographic method (HPLC) for the determination of cyclosporin A (CsA) in human whole blood, and to study the influence of nicotinylmethylamide (Nic) on the pharmacokinetic parameters of cyclosporin A (CsA). METHODS: Whole blood CsA concentrations were measured by HPLC in 18 healthy volunteers administrated single CsA or co administrated Nic. The data of time blood concentrations of CsA were analyzed by 3p97 Program. The analysis of variance and two one sided t test were used to compare the main pharmacokinetic parameters of CsA in the two administrations. RESULTS: C max and AUC 0～∞ of CsA had statistically significance between the single CsA group and co administration of Nic group (P0.05). CONCLUSION: This HPLC method is simple, sensitive and accurate, and is suitable for routine determination of blood CsA levels in human. Nic can improve the absorption of CsA and increase the C max and AUC of CsA, but has no influence on the metabolism of CsA.

Purpose To explore the feasibility of double low dose technology in multi-slice head and neck CT angiography, so to reduce contrast agent as well as reduce radiation dose. In that way, the hazards of radiation and the risk of contrast induced nephropathy would be reduced. Materials and Methods Fifty-one patients took double low proposal were recruited as double low group. Another 51 patients who took conventional proposal were recruited as conventional group. The scanning parameters of double low group were 100 kV, 300 mA, 0.7 ml/kg iodinated contrast agent and which of conventional group were 120 kV, 350 mA, 1.0 ml/kg iodinated contrast agent. The CT value of the vessels and image noise were measured. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective image quality score, radiation dose and iodine load between the two groups were compared. Results The volume CT dose index (CTDIvol) of the double low group and the conventional group were 18.00 mGy and 33.86 mGy, respectively. And the effective dose were 3.85 mSv/(mGy · cm) and 7.25 mSv/(mGy · cm), respectively. The iodine loads were 224 mgI/kg and 320 mgI/kg, respectively. SNR and CNR at the aortic arch were higher in double low group than in conventional group, but which was not statistic significant (t=-1.572 and -1.783, P>0.05). The SNR and CNR of bilateral carotid arteries, internal carotid arteries, and middle cerebral arteries had no statistic significance between the two groups (t=0.341-1.739, P>0.05). The subjective image quality scores of double low group and conventional group were (3.69±0.47) scores and (3.70±0.46) scores, which showed no statistic difference (Z= - 0.213, P>0.05). Conclusion Approving images of multi-slice head and neck CT angiography can be obtained by using double low dose technology without adaptive statistical iterative reconstruction.

Objective To evaluate the changes in the expression of spinal divalent metal transporter 1 (DMT1) during remifentanil-induced hyperalgesia in a rat model of incisional pain.Methods Thirtytwo male Sprague-Dawley rats,weighing 240-260 g,aged 2-3 months,were randomly divided into 4 groups (n =8 each) using a random number table:control group (group C),incisional pain group (group I),remifentanil group (group R),and incisional pain + remifentanil group (group I+R).In group C,normal saline was infused for 60 min at a rate of 0.1 ml · kg-1 · min-1.A 1-cm longitudinal incision was made through skin,fascia and muscle of the plantar aspect of the left hindpaw in sevoflurane-anesthetized rats,and normal saline was infused intravenously for 60 min at a rate of 1.0 μg · kg-1 · min-1 at the same time in group I.In group R,remifentanil was infused for 60 min at a rate of 1.0 μg · kg 1 · min-1 In group I+R,the model of incisional pain was established,and remifentanil was simultaneously infused for 60 min at a rate of 1.0 μg · kg-1 · min-1.At 24 h before normal saline or remifentanil infusion and 6,24 and 48 h after the end of infusion (T0-3),the mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured.All the rats wcrc sacrificed after the last measurement of pain thresholds,and the spinal cord was removed for determination of DMT1 with/without iron-responsive element [DMT1 (+)IRE and DMT1 (-)IRE] expression (by Western blot analysis and immunohistochemistry).Results Compared with group C,the MWT was significantly decreased,and the TWL was significantly shortened at T1-3,and the expression of spinal DMT1 (-) IRE was significantly up-regulated in I,R and I+R groups (P＜0.05).Compared with I and R groups,the MWT was significantly decreased,and TWL was significantly shortened at T1-3,and the expression of spinal DMT1 (-) IRE was significantly upregulated in group I+R (P＜0.05).There was no significant difference in the expression of spinal DMT1 (+) IRE between the four groups (P＞ 0.05).Conclusion Spinal DMT1 (-)IRE activation may be involved in the mechanism underlying remifentanil-induced hyperalgesia in a rat model of incisional pain.

Objective To evaluate the effects of different ratios of medicine dosage for sevoflurane and propofol on postoperative cognitive function in aged rats.Methods Sixty healthy male Wistar rats,aged 18-20 months,weighing 600-650 g,were divided into 6 groups (n =10 each) using a random number table:control group (group C),sevoflurane anesthesia group (group S),propofol anesthesia group (group P) and different ratios of mmedicine dosage for sevoflurane and propofol groups (group SP1,group SP2 and group SP3).Normal saline 10 ml was infused intravenously in group C.Group S inhaled 3.1％ sevoflurane.Propofol was infused intravenously at a rate of 40 mg · kg-1 · h-1 in group P.In group SP1,2.4％ sevoflurane was inhaled,and propofol was intravenously infused at a rate of 10 mg · kg-1 · h-1.In group SP2,1.8％ sevoflurane was inhaled,and propofol was intravenously infused at a rate of 20 mng · kg-1 · h-1.In group SP3,1.2％ sevoflurane was inhaled,and propofol was intravenously infused at a rate of 30 mg · kg-1 · h-1.Duration of anesthesia was 2 h in all the groups.After loss of righting reflex,open reduction and internal fixation was performed after tibial fracture was induced in the other five groups except group C.At 1 day after anesthesia,Y-maze test was performed,and the time spent on the novel arm and total number of entries into each arm were recorded,and fear conditioning test was carried out for determination of the rate of freezing time to reflect the cognitive function.The rats were sacrificed after behavioral testing,and the hippocampus was removed for determination of occludin,matrix metalloproteinase-2 (MMP-2) and MMP-9 expression by Western blot.Results Compared with group C,the time spent on the novel arm was significantly shortened,the total number of entries into each arm and rate of freezing time were decreased,the expression of occludin was down-regulated,the expression of MMP-2 and MMP-9 was up-regulated in the other five groups,and the most unmarked change in the indices mentioned above was found in group SP2 (P＜ 0.05 or 0.01).Conclusion Different ratios of medicine dosage for sevoflurane and propofol can induce postoperative cognitive decline,and inhaling 1.8％ sevoflurane and infusing propofol 20 mg · kg-1 · h-1 produce little influence on postoperative cognitive function in aged rats.

Objective To construct a technical platform for scarless gene modification of Yersinia pestis and to study the functions of its specific genes.Methods The resistance fragment, including upstream and downstream homologous arms of targeted regions, was reamplified by asymmetric PCR.The amplicons were introduced into Y.pestis harboring plasmid pKD46.With the induction of L-arabinose,the recombinant related enzymes: Exo, Beta and Gam, were expressed to guide the homologous recombination.A donor plasmid, pKSI-1, which carried the desired modification fragment flanking by I-SceⅠ recognition sites, was introduced into Y.pestis as the second step of λ-Red recombination with the help of pREDTKI.Results and Conclusion Two mutant strains:△waaA and waaA(△9nt), were successfully constructed for Y.pestis strain 201.Scarless modification introduces no extra modification to the genome, and it is ideal for comprehensive functional genomic studies.

Objective To investigate the value of ADC histogram in the differential diagnosis of angiomatous meningioma (AM) and hemangiopericytoma (HPC)and to screen out the best diagnostic parameter.Methods The MRI data of 21 cases with AM and 22 cases with HPC confirmed by surgical pathology were analyzed retrospectively.The ROI were drawn on the maximum cross section of the tumor on ADC maps,and the ADC histogram analysis was performed using the software named Mazda.Then the histogram parameters were statistically analyzed to find out the statistically significant parameters between the two groups,and the ROC curve was drawn to evaluate their diagnostic efficacy.Results ADCvariance ,ADC1th and ADC10th had statistical significances between the two groups (P＝0.030,0.002 and 0.02 1 ). ADC1th had the best diagnostic efficacy among them,with the optimal cut-off value of 0.086×10－3 mm2/s,the AUC was 0.814(P＝0.003),and the sensitivity and specificity were 86.70%and 64.70%,respectively.ADCvariance took the second place,for the AUC was 0.725 (P＝0.030),and the sensitivity and specificity were 7 6.50%and 80.00%,respectively.Conclusion The ADC histogram is of great value in the differential diagnosis of AM and HPC,and the ADC1th is the most effective parameter.

Objective To evaluate the changes in the expression of artemin in skin around the inci-sion during remifentanil-induced hyperalgesia in the rats with incisional pain. Methods Thirty-two healthy male Sprague-Dawley rats, aged 10-12 weeks, weighing 250-280 g, were divided into 4 groups (n = 8 each) using a random number table: control group (group C), incisional pain group (group I), remifen-tanil group (group R) and incisional pain plus remifentanil group (group I+R). Remifentanil was intrave-nously infused for 60 min at a rate of 1 μg·kg-1 ·min-1 in group R. In group I, the model of incisional pain was established, and the equal volume of normal saline was infused for 60 min via the tail vein at the same time. In group I+R, the model of incisional pain was established, and remifentanil was infused for 60 min via the tail vein at a rate of 1 μg·kg-1 ·min-1 at the same time. The equal volume of normal saline was infused for 60 min via the tail vein in group C. Mechanical paw withdrawal threshold (MWT) and ther-mal paw withdrawal latency (TWL) were measured at 24 h before infusion of remifentanil or normal saline and 2, 6, 24 and 48 h after the end of infusion (T0-4 ). Rats were sacrificed following the last measurement of pain threshold, and ipsilateral plantar skin was removed for detection of the expression of artemin protein and mRNA (by fluorescent quantitative real-time polymerase chain reaction or Western blot). Results Compared with group C, MWT was significantly decreased and TWL was shorten at T1-4 , and the expression of artemin protein and mRNA in plantar skin was up-regulated in R, I and I+R groups (P<0. 01). Compared with R and I groups, MWT was significantly decreased and TWL was shorten at T1-4 , and the ex-pression of artemin protein and mRNA in plantar skin was up-regulated in group I+R (P<0. 01). Conclu-sion The peripheral mechanism by which remifentanil induces hyperalgesia may be related to up-regulated expression of artemin in skin around the incision in the rats with incisional pain.

Based on WeChat platform,blended teaching is designed and implemented in oral surgery practice.The undergraduate intern can get in touch with the internship early,become familiar with it early and make an internship program early.In the process of internship,they can achieve the purpose of getting more questions,more summary and more test through teaching,discussing and contesting.After the internship,they can consolidate,review,exchange and expand learning.The preliminary practice shows that the teaching stimulates the students' interest and motivation in the clinical study of oral surgery,enhances the interaction between teachers and students and the supervision of the teachers to the students,and improves the effect of the practice teaching.

Objective To evaluate the role of spinal C-C motif chemokine receptor 5 (CCRS) in remifentanil-induced hyperalgesia in rats with incisional pain.Methods Thirty-two male Sprague-Dawley rats,weighing 240-260 g,aged 2-3 months,in which intrathecal and caudal catheters were successfully implanted,were divided into 4 groups (n =8 each) using a random number table:control group (group C),CCR5 antagonist maraviroc group (group M),remifentanil plus incisional pain group (group R + I) and maraviroc plus remifentanil plus incisional pain group (group M + R + I).Phosphate buffer solution (PBS) 10 μl was intrathecally injected and normal saline was infused for 60 rnin at 1 μg · kg-1 · min-1 via the caudal vein in group C.Maraviroc 100 pmol (in 10 μl of PBS) was intrathecally injected and normal saline was infused for 60 min at 1 μg · kg-1 · min-1 via the caudal vein in group M.PBS 10 μl was intrathecally injected,then the model of incisional pain was established,and remifentanil 1 μg · kg-1 · min-1 was infused for 60 min via the caudal vein in group R+I.Maraviroc 100 pmol (in 10 μl of PBS) was intrathecally injected,then the model of incisional pain was established,and remifentanil 1 μg · kg-1 · min-1 was infused for 60 min via the caudal vein in group M+R+I.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured at 24 h before infusion of remifentanil or normal saline (T0) and 2,6,24 and 48 h after stopping infusion (T1-4).The rats were sacrificed after the last measurement of pain threshold,and L4-6 segments of the spinal cord were removed for determination of the expression of glial fibrillary acidic protein (GFAP) and ionized calciumbinding adapter molecule-1 (Iba-1) by Western blot.Results Compared with group C,the MWT was significantly decreased and TWL was shortened at T1-4,and the expression of GFAP and Iba-1 in the spinal cord was up-regulated in R+I and M+R+I groups (P＜0.05),and no significant change was found in the parameters mentioned above in group M (P＞0.05).Compared with group R+I,the MWT was significantly increased and TWL was prolonged at T1-4,and the expression of GFAP and Iba-1 in the spinal cord was down-regulated in group M+R+I (P＜0.05).Conclusion Spinal CCR5 is involved in remifentanil-induced hyperalgesia in the rats with incisional pain,and the mechanism may be related to activating astrocytes and microglias.

Objective To evaluate the effect of remifentanil on iron metabolism in spinal dorsal horn neurons of rats.Methods The primary spinal dorsal horn neurons of rats were seeded in the culture plate at a density of 2× 105 cells/well and divided into 4 groups using a random number table method:control group (C group,n=40),remifentanil group (R group,n=40),divalent metal transporter 1 without iron-responsive element [DMT1 (-) IRE] siRNA group (siRNA group,n=32) and DMT1 (-) IRE siRNA plus remifentanil group (siRNA+R group,n=32).siRNA and siRNA+R groups were subjected to DMT1 (-) IRE siRNA transfection on day 3 of culture.R and siRNA+R groups were incubated for 60 min in the solution with remifentanil at a final concentration of 40 nmol/L.The contents of reactive oxygen species (ROS) and Fe2+ were determined by fluorescent probe method,the malondialdehyde (MDA) content was detected by TBA method,and the content of labile iron pool (LIP) was detected by calcein AM and iron chelator at the end of incubation with remifentanil in R and siRNA+R groups and at the corresponding time points in the other groups.The expression of DMT1 (-) IRE and DMT1 (+) IRE was determined by Westem blot in C and R groups.Results Compared with C group,the expression of DMT1 (-) IRE in the spinal dorsal horn neurons was significantly up-regulated,the contents of Fe2+,LIP,ROS and MDA were increased (P＜0.05),and no significant change was found in the expression of DMT1 (+) IRE in R group (P＞0.05).Compared with R group,the contents of Fe2+,LIP,ROS and MDA in the spinal dorsal horn neurons were significantly decreased in siRNA+R group (P＜0.05).Conclusion Remifentanil increases the iron content of spinal dorsal horn neurons by activating DMT1 (-) IRE,which may be associated with the mechanism of remifentanil-induced postoperative hyperalgesia in rats.