Polycythemia vera (PV) is a chronic clonal myeloproliferative disorder of hematopoietic stem cell characterized by a pronounced symptom burden, including fatigue, pruritus, and symptomatic splenomegaly, along with an increased risk of thrombosis and the potential for evolution to myelofibrosis (MF) and secondary acute myeloid leukemia. Research on pathogenesis, diagnosis and treatment of PV has made a great progress since the discovery of JAK2 V617F mutation in 2005. The change of epigenetics plays an important role in the progression of PV, and the drugs for apparent genetic alteration may improve the life quality of PV patients.

Objective To investigate the effects of pretreatment with remifentanil on hemorrhagic shock (HS)-induced acute liver injury in rabbits.Methods Thirty-two New Zealand white rabbits,weighing 2.0-2.5 kg,were randomly divided into 4 groups (n=8 each): sham operation group (group S) ; group HS,low-dose remifentanil group (group RL) ; high-dose remifentanil group (group RH).Remifentanil was infused at 0.66 and 1.32 μg· kg-1 · min-1 for 145 min in groups RL and RH respectively,while the equal volume of normal saline was infused in group C.HS was induced by withdrawing blood from the left femoral artery at 15 min after continuous infusion of normal saline or remifentanil and mean arterial pressure (MAP) was reduced to 40 mm Hg.MAP was reduced to 35-45 mm Hg and maintained at this level for 120 min in groups HS,RL and RH.Blood samples were taken for determination of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities before administration (T0),immediately before blood letting (T1),and at 10,30,60 and 90 min after blood letting (T3-6).The animals were then sacrificed and the livers were immediately removed for microscopic examination.Results Compared with group S,the serum ALT activity at T5 and T6 and serum AST activity at T4-T6 were significantly increased in the other three groups (P ＜ 0.05).Compared with group HS,the serum ALT activity at T5 and T6,and serum AST activity at T4-T6 were significantly decreased in group RH,and no significant change was found in group RL (P ＞ 0.05).Compared with group RL,the serum ALT activity at T5 and T6,and serum AST activity at T4-T6 were significantly decreased in group RH (P ＜ 0.05).The serum ALT activity at T5 and T6 and serum AST activity at T4-T6 were significantly increased in groups HS,R and RH than those at T0 (P ＜ 0.05 or 0.01).The patho1ogical injury was attenuated in group RH compared with groups HS and RL.Conclusion Remifentanil pretreatment can attenuate HS-induced acute liver injury in rabbits,and the effect is related to the dose.

Objective To investigate the predictive value of the non-invasive indicator deceleration capacity of heart rate (DC) in the sudden cardiac death (SCD) after acute myocardial infarction. Methods A total of 417 myocardial infarc?tion patients with ST-segment elevation in sinus rhythm were enrolled in this study. DC was assessed from data of 24-hour ECG Holter. Regular follow-ups were carried out within 12 months. The SCD events were recorded and compared with pa?tients without SCD. Results During 12 months of follow-up, 20 patients were died due to SCD (4.8%). Compared with sur?vival group, patients showed significantly lower left ventricular ejection fraction (LVEF, 0.393 ± 0.065 vs 0.528 ± 0.042, P<0.05) and DC [(2.85±1.66) ms vs (5.49±1.71) ms,P<0.05]in SCD group. Multivariate Cox proportional hazard regression analysis showed that lower LVEF(<0.35)[RR: 2.167(1.384-4.661), P=0.013]and DC (DC<4.5 ms)[RR: 3.706(2.709-5.374),P=0.020]were risk factors for the occurrence of SCD. The prediction sensitivity by the decreased LVEF and DC was 52.1%and 76.4%respectively, and the specificity was 84.5%and 86.1%respectively. Conclusion The decreased value of DC after acute myocardial infarction can predict the SCD events.

Objective To investigate the effects of remifentanil on lipid peroxidation druing hemorrhagic shock-induced acute lung injury (ALI) in rabbits. Methods Thirty-two healthy adult rabbits weighing 2.0-2.5 kg were randomly divided into 4 groups (n = 8 each): sham operation group (group S); ALI group; low-dose remifentanil group (group LR); high-dose remifentanil group (group HR). The left femoral artery was cannulated for blood-letting and blood sampling. The right femoral artery was cannulated for remifentanil administration. The model of hemorrhagic shock was established by modified Wigger' s methods. In group S, only cannulation was performed. In group LR and HR, remifentanil was infused intraperitoneally at 0.66 and 1.32 μg·kg-1 ·min-1 15 min before blood-letting respectively, while group ALI received equal volume of normal saline instead. Arterial blood samples were taken at 0, 20,70 and 100 min after blood-letting (T1-4) for blood gas analysis. The animals were then sacrificed and the lungs were immediately removed for histological examination with light microscope and determination of W/D lung weight ratio, MDA content and SOD activity. Results W/D ratio and MDA content were significantly increased, while SOD activity was significantly decreased in group ALI compared with group S (P ＜0.05). The pH value at T2 and PaO2 at T2-4 in group LR and the pH value and PaCO2 at T2-4 in group HR were significantly higher than those in group ALI (P ＜ 0.05). W/D ratio and MDA content were significantly lower,while SOD activity was significantly higher in group LR and HR than in group ALI, and in group HR than in group LR (P ＜ 0.05). Remifentanil infusion significantly attenuated the pathologic changes in a dose-dependent manner. Conclusion Remifentanil pretreatment can attenuate hemorrhagic shock-induced ALI through inhibiting lipid peroxidation in rabbits.

Objective: To observe the eff ect and mechanism of chronic high-fat diet on predation behavior in rats. Methods: Ten female SD rats with 4-week-old were randomly divided into a normal control group (NC group,n=5) and a chronic high-fat diet group (HF group,n=5). The rats in the NC group received the regular diet while rats in the HF group were fed with high-fat diet. Fitf een weeks later, the predation behavior of rats was evaluated by open if eld test and food foraging tests. At the end of experiments, the rats were killed and brain tissues were collected for evaluation of c-Fos protein expression in anterior cingulate cortex by immunohistochemical assay. Results: hT e predation behavior of rats in the HF group was signiif cantly impaired in the competitive or non-competitive food foraging test compared with the control rats (P<0.001). hT e c-fos protein expression in anterior cingulate cortex of rats from the HF group was signiif cantly decreased (P<0.001). Conclusion: Long time high-fat diet can aff ect the predation behavior of rats, which is related todysfunction of neuron in anterior cingulate cortex.

Objective To investigate the effects of peptidoglycan (PGN) with different concentrations on Toll-like receptor 2 (TLR2),Toll-like receptor 4 (TLR4) expression in corneal epithelial cells of mice.Methods Corneal epithelial cells of c57 mice were cultured in vitro.Cells were divided into blank control group and 10 mg · L-1 group,30 mg · L-1 gruop and 80 mg · L-1 group (treated by different concentration of PGN for 12 hours).In the meantime,the cells in 30 mg · L-1 group were cultured for different times(named 12 hours group,24 hours group,36 hours group).Expressions of TLR2 and TLR4 mRNA and protein in different group were measured by RT-PCR and flow cytometry.Results Compared with control group (1.00 ± 0.14,1.00 ± 0.01),the expression of TLR2,LR4 mRNA in 10 mg · L-1 group (4.35 ± 0.46,3.53 ± 0.50),30 mg · L-1 group (8.06 ±0.72,5.31 ±0.34),80 mg · L-1 group (2.93 ±0.46,2.23 ±0.04) were increased,the differences were statistically significant (all P ＜ 0.05).Compared with control group,the expression of TLR2,TLR4 protein in different concentration group and 12 hour group were increased,the differences were statistically significant (all P ＜ 0.05).Conclusion PGN can up-regulate both mRNA and protein expression of TLR2 and TLR4 in corneal epithelial cells of mice,suggest that TLR2 and TLR4 in the corneal epithelial cell can recognize some exogenous pathogen and regulate the inflammatory reaction,which are closely related to the occurrence and development of infectious keratitis.

OBJECTIVEThe plasmid construction and validation of RET point mutation in vitro.METHODS The RET gene exon in the mainland familial medullary thyroid carcinoma family was analized with muon capture two generation sequencing of. In vitro, the RET relative point mutationswere reconstructed in NIH3T3 cells and the expression levels were studied.RESULTSThe corresponding lentiviral plasmids of RET point mutations were successfully obtained after point mutating the wild RET plasmids, it was verified that the target genes were expressed in NIH3T3 cells stably by Western Blot. CONCLUSIONSStable cell lines carrying RET point mutations were reconstructedsuccessfully, which provide a good platform for studying various point mutations.

Objective: To observe the automatic ventricular capture management (VCM) conifrmed by paced depolarization integral (PDI) evoked response detection via the follow-up study in patients with Zephyr5826 pacemaker implantation. Methods: A total of 102 relevant patients were enrolled. In order to conduct PDI calculation, pacemakers were set by bipolar sensing and bipolar pacing at immediately after implantation. VCM functions were observed at 1 day, 7 days and 1 month, 3, 6, 12 months after implantation, the ventricular threshold by VCM test and manual test were compared. The symptoms of pectoralis major stimulus, diaphragm stimulus and palpitation were observed in all follow-up patients. Results: There was 1 patient died by MI at 1 month after Zephyr5826 pacemaker implantation, the rest 101 patients were followed-up for 12 months. VCM function was successfully turned-on at immediately after implantation in all patients, no pectoralis major stimulus and diaphragm stimulus occurred. VCM function was turned-off in 6/101 (5.9%) patients at 7 days after implantation due to intolerable palpitation caused by daily automatic VCM, instead they received manual test at follow-up visit. The coincidence rate of ventricular thresholds between VCM test and manual test were 100%. Ventricular pacing output voltage by VCM was (0.99 ± 0.48) V,n=608. Compared with regular pacing output voltage (2.5V, 0.4ms), VCM function may save 84% of energy consumption; compared to high pacing output voltage (3.5V, 0.4ms), VCM may save 92%. Loss of ventricular capture and poor sensation were not found by ECG and 24 h dynamic monitoring. Conclusion: Zephyr5826 pacemaker may conduct bipolar pacing and scanning with VCM function, it can be effectively and safely operated by low energy output. A few patients may not use VCM function due to intolerable palpitation.

BACKGROUND:Digital three-dimensional model which can reflect the fine structure of the chambers inside heart not only enhances the understanding of cardiac physiology, but also provides basic medical data for the study of cardiac electrophysiology simulation and endocardial electrophysiological mapping navigation. OBJECTIVE:To construct the digital three-dimensional model of cardiac cavity from sectional data and in conformity with the actual anatomical structure. METHODS:Image segmentation was accomplished in MATLAB environment. Firstly, registration of human cardiac cavity slice dataset was realized. Secondly, classifying each composition was achieved by clustering method according to color characteristics of the image. Then, both cardiac cavity and related connected region was distinguished by region growing method. At last, the processed image was reconstructed through dedicated medical processing software into three-dimensional model of the cardiac cavity. RESULTS AND CONCLUSION:The proposed method could reconstruct quite exquisite three-dimensional model of the cardiac cavity. In models, left and right atrial and ventricular structure was clear. Aorta and superior vena cava were visible. Three tricuspid and mitral valve were also observed. Results indicated that reconstructed model can reflect the anatomical characteristics of cardiac cavity accurately, and provide basic medical data for the study on electrophysiological simulation and endocardial electric mapping.

OBJECTIVETo determine the pesticide residues in Shengmaiyin.

METHODThe residues were simultaneously identified and quantified by capillary gas chromatography. The capillary column was OV-1701(0. 32 mm x 30 m, 0.5 microm), splitless injection and Agilent 63Ni electron capture detector ECD were adopted. The carrier gas were high-pure nitrogen, the flow rate were 60 mL x min(-1), the injector temperature was 260 degrees C, and the detector temperature was 300 degrees C.

RESULTIt showed a good linear relationship between peak area and pesticide concentration for 11 kinds of pesticides in the detection concentration range. All correlation coefficients were higher than 0.996 2. The average recovery was 83.1% -114.7%.

CONCLUSIONA simple and efficient monitoring method of pesticide residues is established which provides the foundation for the safe use and analysis of Shengmaiyin.