Improved methodology for efficient establishment of the myocardial ischemia-reperfusion model in pigs through the median thoracic incision

To investigate the feasibility and effectiveness of establishing porcine ischemia-reperfusion models by ligating the left anterior descending(LAD)coronary artery,we first randomly divided 16 male Bama pigs into a sham group and a model group.After anesthesia,we separated the arteries and veins.Subsequently,we rapidly located the LAD coronary artery at the beginning of its first diagonal branch through a mid-chest incision.Then,we loosened and released the ligation line after five minutes of pre-occlusion.Finally,we ligated the LAD coronary artery in situ two minutes later and loosened the ligature 60 min after ischemia.Compared with the sham group,electrocardiogram showed multiple continuous lead ST-segment elevations,and ultrasound cardiogram showed significantly lower ejection fraction and left ventricular fractional shortening at one hour and seven days post-operation in the model group.Twenty-four hours after the operation,cardiac troponin T and creatine kinase-MB isoenzyme levels significantly increased in the model group,compared with the sham group.Hematoxylin and eosin staining showed the presence of many inflammatory cells infiltrating the interstitium of the myocardium in the model group but not in the sham group.Masson staining revealed a significant increase in infarct size in the ischemia/reperfusion group.All eight pigs in the model group recovered with normal sinus heart rates,and the survival rate was 100%.In conclusion,the method can provide an accurate and stable large animal model for preclinical research on ischemia/reperfusion with a high success rate and homogeneity of the myocardial infarction area.

Robust Solution for Boundary Layer Height Detections with Coherent Doppler Wind Lidar

Although coherent Doppler wind lidar(CDWL)is promising in detecting boundary layer height(BLH),differences between BLH results are observed when different CDWL measurements are used as tracers.Here,a robust solution for BLH detections with CDWL is proposed and demonstrated:mixed layer height(MLH)is retrieved best from turbulent kinetic energy dissipation rate(TKEDR),while stable boundary layer height(SBLH)and residual layer height(RLH)can be retrieved from carrier-to-noise ratio(CNR).To study the cause of the BLH differences,an intercomparison experiment is designed with two identical CDWLs,where only one is equipped with a stability control subsystem.During the experiment,it is found that the CNR could be distorted by instrument instability because the coupling efficiency from free-space to the polarization-maintaining fiber of the telescope is sensitive to the surrounding environment.In the ML,a bias up to 2.13 km of the MLH from CNR is found,which is caused by the CNR deviation.In contrast,the MLH from TKEDR is robust as long as the accuracy of wind is guaranteed.In the SBL(RL),the CNR is found capable to retrieve SBLH and RLH simultaneously and robustly.This solution is tested during an observation period over one month.Statistical analysis shows that the root-mean-square errors(RMSE)in the MLH,SBLH,and RLH are 0.28 km,0.23 km,and 0.24 km,respectively.

Photon-counting distributed free-space spectroscopy

Spectroscopy is a well-established nonintrusive tool that has played an important role in identifying and quantifying substances,from quantum descriptions to chemical and biomedical diagnostics.Challenges exist in accurate spectrum analysis in free space,which hinders us from understanding the composition of multiple gases and the chemical processes in the atmosphere.A photon-counting distributed free-space spectroscopy is proposed and demonstrated using lidar technique,incorporating a comb-referenced frequency-scanning laser and a superconducting nanowire single-photon detector.It is suitable for remote spectrum analysis with a range resolution over a wide band.As an example,a continuous field experiment is carried out over 72 h to obtain the spectra of carbon dioxide(CO_(2))and semi-heavy water(HDO,isotopic water vapor)in 6 km,with a range resolution of 60 m and a time resolution of 10 min.Compared to the methods that obtain only column-integrated spectra over kilometer-scale,the range resolution is improved by 2-3 orders of magnitude in this work.The CO_(2)and HDO concentrations are retrieved from the spectra acquired with uncertainties as low as±1.2%and±14.3%,respectively.This method holds much promise for increasing knowledge of atmospheric environment and chemistry researches,especially in terms of the evolution of complex molecular spectra in open areas.

Protein kinases in cardiovascular diseases

Cardiovascular disease(CVD)remains the leading cause of death worldwide.Therefore,exploring the mechanism of CVDs and critical regulatory factors is of great significance for promoting heart repair,reversing cardiac remodeling,and reducing adverse cardiovascular events.Recently,significant progress has been made in understanding the function of protein kinases and their interactions with other regulatory proteins in myocardial biology.Protein kinases are positioned as critical regulators at the intersection of multiple signals and coordinate nearly every aspect of myocardial responses,regulating contractility,metabolism,transcription,and cellular death.Equally,reconstructing the disrupted protein kinases regulatory network will help reverse pathological progress and stimulate cardiac repair.This review summarizes recent researches concerning the function of protein kinases in CVDs,discusses their promising clinical applications,and explores potential targets for future treatments.