Objective To investigate molecular diagnostic method for hereditarymethemoblobinemia. Methods The cDNA coding sequence of NADH-cytochrome b5 reductase (b5R) from 3 patients with hereditary methemoglobinemia was analyzed by direct sequencing of RT-PCR products and the genomic DNA of b5R gene by PCR-restriction endonuclease digestion or PCR-sequencing. Results The b5R cDNA of patient A was T/C heterozygous at nucleotide 527 and G/A heterozygous at nucleotide 608. The b5R cDNA of patient B was G/A heterozygous at both nucleotide 170 and nucleotide 179. The b5R cDNA of patient C was G/A heterozygous at nucleotide 608 and C/T heterozygous at nucleotide 791. Result of genomic DNA analysis was in agreement with that of cDNA approach. Conclusion The method for molecular diagnosis of hereditary methemoglobinemia was established and 3 novel b5R gene mutations were identified in compound heterozygosity in 3 Chinese patients.

Objective:To observe influence of up‐regulated expression of myocardial heat shock protein (HSP) 70 in‐duced by heat stress on myocardial calcium‐activated potassium channel (KCa ) 3.1 expression in rabbits with atrial fibrillation (AF) caused by rapid atrial pacing (RAP) .Methods :A total of 24 New Zealand white rabbits were ran‐domly divided into sham operation group (n=8 ,only implant electrode without pacing ) ,pacing group (n=8 ,right atrium (RA) received RAP at 600 times/min for 6h) and heat stress pacing group (heat stress group ,n=8 ,received heat stress preconditioning ,then the same RAP as pacing group ) .Results:Compared with sham operation group and pacing group ,there were significant up‐regulation of HSP70 mRNA and protein expression in different sites of heart [HSP70 protein ,left atrium (LA):(39.00 ± 3.21) vs .(39.75 ± 2.82) vs .(69.75 ± 3.45) ,RA: (38.38 ± 2.92) vs .(39.50 ± 3.89) vs .(69.00 ± 2.93) ,left atrial appendage (LAA):(37.75 ± 3.28) vs .(39.00 ± 3.89) vs . (68.63 ± 3.23) ,right atrial appendage (RAA): (37.00 ± 3.85) vs .(38.38 ± 3.74) vs .(68.75 ± 2.82)] in heat stress group , P<0. 01 all ,but there were no significant difference between pacing group and sham operation group , P>0.05 ;compared with pacing group with down‐regulation of KCa3.1 mRNA and protein expressions ,there were significant up‐regulation of KCa3.1 mRNA and protein expressions in different sites of heart [KCa3.1 protein ,LA:(21.25 ± 1.67) vs .(24.00 ± 2.62) ,RA :(21.13 ± 1.96) vs .(23.75 ± 1.83) ,LAA :(21.00 ± 2.07) vs .(23.75 ± 1.67) ,RAA:(20.88 ± 2.03) vs .(23.50 ± 2.45)] in heat stress group ,P<0.05 all ,and there were no significant difference between heat stress group and sham operation group , P>0. 05. Conclusion:Heat stress may induce up‐regulated expression of myocardial HSP 70 of myocardium ,and HSP 70 may inhibit down‐regulation of KCa 3. 1 mR‐NA and protein expressions in rabbits with atrial fibrillation.

Objective:To explore influence of thrombus aspiration combined bivalirudin during emergency PCI on my- ocardial tissue perfusion and clinical prognosis in patients with acute ST elevation myocardial infarction (STEMI). Methods:A total of 102 patients with acute STEMI,who were confirmed with thrombus burden by CAG in our hos- pital from Jan 2012 to Jun 2014,were selected.According to random number table,they were randomly divided into thrombus aspiration + bivalirudin group (n=52,thrombus aspiration group)and heparin group (n=50,routine PCI group).TIMI blood flow grade 3 rate,TIMI myocardial perfusion grade (TMPG)after PCI,ST segment re- gression rate 2h after PCI,peak value and peak time of cTnI after PCI,LVEF,LVEDd,incidence rates of bleeding and major adverse cardiovascular events (MACE)on one week and one month after PCI were compared between two groups.Results:Compared with routine PCI group,there were significant rise in postoperative TMPG grade 3 rate (56.00% vs.88.46%),TIMI grade 3 rate (58.00% vs.88.46%)and ST segment regression rate (52.00% vs. 76.92%)in thrombus aspiration group,P<0.05 or <0.01. Compared with routine PCI group one month after PCI,there was significant rise in LVEF [(53.76±5.24)% vs.(57.95±5.51)%],and significant reductions in LVEDd [(53.70±3.39)mm vs.(50.63±1.24)mm],peak value [(16.00±4.28)μg/L vs.(13.81±4.00)μg/L]and peak time [(14.00±2.80)h vs.(13.00±2.23)h]of cTnI in thrombus aspiration group,P<0.05 or <0.01. Incidence rate of mild bleeding in thrombus aspiration group was significantly lower than that of routine PCI group (1.9% vs.16.0%),P<0.05,but there was no significant difference in incidence rate of MACE between two groups,P>0.05. Conclusion:Thrombus aspiration combined bivalirudin during emergency PCI is safe and fea- sible for acute STEMI patients,it can effectively reduce incidence rate of bleeding,remove coronary thrombus,im- prove myocardial tissue perfusion and doesn't increase incidence rate of MACE.