Reactive protein, plasminogen activator inhibitor type-1 （PAI-1） levels, PAI-1 promoter 4G/5G polymorphism and acute myocardial infarction

Objective To investigate the relationship between CRP, plasminogen activator inhibitor type 1 （PAI-1） levels, PAI-1 gene promoter 4G/5G polymorphism and the type of acute myocardial infarction （ST elevation myocardial infarction, STEMI vs the non-ST elevation Myocardial infarction, NSTEMI）. Methods One hundred seventy-six consecutive patients with AMI were included for the study, of whom 60 had STEMI and 56 had NSTEMI, and 60 adults without cardiovascular and cerebrovascular disease were selected as controls. Blood samples were obtained from patients within 6 h of AMI and the plasma PAI-1, CRP, and the gene polymorphism were measured. Results Plasma levels of PAI- 1 and CRP were higher in AMI groups, compared those in the control group, and plasma levels of PAI-1 were significantly higher in patients with STEMI compared to those with NSTEMI （80.12ng/ml VS.73.01ng/ml, P 〈0.01）, while CRP levels were not significantly different between patient with STEMI and NSTEMI （3.87 ± 0.79 mg/ml VS.4.01 ±0.69mg/ml, P〉0.05）. PAI-1 levels presented a significant correlation with CRP levels in the NSTEMI subjects. However, PAI-1 and CRP levels could explain the lack of a significant relationship between them in control and STEMI subjects.The frequencies of 4G/4G genotype in the AMI group were higher than those in the control group and higher in patient with STEMI than in patient with NSTEMI. Plasma levels of PAI-1 in subjects with 4G/4G genotype were significantly increased as compared to those in subjects with 4G/5G and 5G/5G genotype. Conclusions Plasma PAI-1 levels were associated with different myocardial infarction type, and PAI-1 promoter 4G/5G polymorphisms and CRP may be related to plasma PAI-1 levels

Timing analysis of the black hole candidate EXO 1846–031 with Insight-HXMT monitoring

We present the observational results from a detailed timing analysis of the black hole candidate EXO 1846-031 during its outburst in 2019 with the observations of Insight-HXMT,NICER and MAXI.This outburst can be classified roughly into four different states.Type-C quasi-periodic oscillations(QPOs)observed by NICER(about 0.1-6 Hz)and Insight-HXMT(about 0.7-8 Hz)are also reported in this work.Meanwhile,we study various physical quantities related to QPO frequency.The QPO rms-frequency relationship in the energy band 1-10 keV indicates that there is a turning pointing in frequency around2 Hz,which is similar to that of GRS 1915+105.A possible hypothesis for the relationship above may be related to the inclination of the source,which may require a high inclination to explain it.The relationships between QPO frequency and QPO rms,hardness,total fractional rms and count rate have also been found in other transient sources,which can indicate that the origin of type-C QPOs is non-thermal.

Five-year in-orbit background of Insight-HXMT

Purpose We present the five-year in-orbit background evolution of Insight-HXMT since the launch,as well as the effects of the background model in data analysis.Methods The backgrounds of the three main payloads,i.e.,low-energy telescope,medium-energy telescope,and high-energy telescope,are described.The evolution of the background over time is obtained by simply comparing the background in every year during the in-orbit operation of Insight-HXMT.Results The major observational characteristics of the Insight-HXMT in-orbit background are presented,including the light curve,spectrum,geographical distribution,and long-term evolution.The systematic error in background estimation is investigated for every year.Conclusion The observational characteristics of the five-year in-orbit background are consistent with our knowledge of the satellite design and the space environment,and the background model is still valid for the latest observations of Insight-HXMT.