High altitude heart disease(HAHD)is a chronic mountain sickness in which the body is exposed to high altitude(＞2 500 m)hypobaric hypoxia environment for a long time.HAHD has high morbidity and poor prognosis,and pulmonary hypertension is the main causative mechanism for its develop-ment.The phosphodiesterase-5 inhibitor sildenafil has become a hot drug for the treatment of pulmonary hypertension.This paper reviews the progress of HAHD and discusses the mechanism of action and effectiveness of sildenafil in the treatment of HAHD,with a view to providing a basis for the treatment of HAHD with sildenafil.

Objective To investigate the value of low tube voltage and low dose contrast agents combined with artificial intelligence iterative reconstruction(AIIR)in upper limb CT angiography(CTA)for displaying arteriovenous fistula(AVF).Methods Totally 65 patients with chronic renal failure and suspected AVF stenosis who underwent upper limb CTA were prospectively enrolled and randomly divided into conventional-dose group(CD group,n=30)and low-dose group(LD group,n=35).In CD group,CTA was acquired using conventional tube voltage(100 kVp)and contrast agents dosage(1.0 ml/kg body mass),and conventional hybrid iterative reconstruction(HIR)was used to reconstruct images(group A),while in LD group,CTA was collected using 80 kVp and contrast agent dosage of 0.6 ml/kg body mass,and images were reconstructed with HIR(group B)and AIIR(group C),respectively.Then subjective and objective assessment of imaging quality were performed,respectively,the results were compared among groups,while the radiation dose and dosage of contrast agents were compared between CD and LD groups.Results No significant difference of subjective score of imaging quality nor confidence for diagnosing AVF stenosis was found between group A and group C(both P＞0.017),and all the above scores were higher than those in group B(all P＜0.017).Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of subclavian artery,brachial artery and radial artery in group C were all higher than those in groups A and B(all P＜0.017),while no significant difference of SNR nor CNR was found between group A and B(all P＞0.017).The volume CT dose index,dose length product and dosage of contrast agent in LD group were all lower than those in CD group(all P＜0.001).Conclusion Low tube voltage and low dose contrast agents combined with AIIR in upper limb CTA for displaying AVF could reduce radiation dose and contrast agents dosage under the condition of ensuring imaging quality.

High altitude heart disease(HAHD)is a chronic mountain sickness in which the body is exposed to high altitude(＞2 500 m)hypobaric hypoxia environment for a long time.HAHD has high morbidity and poor prognosis,and pulmonary hypertension is the main causative mechanism for its develop-ment.The phosphodiesterase-5 inhibitor sildenafil has become a hot drug for the treatment of pulmonary hypertension.This paper reviews the progress of HAHD and discusses the mechanism of action and effectiveness of sildenafil in the treatment of HAHD,with a view to providing a basis for the treatment of HAHD with sildenafil.

Objective To investigate the value of low tube voltage and low dose contrast agents combined with artificial intelligence iterative reconstruction(AIIR)in upper limb CT angiography(CTA)for displaying arteriovenous fistula(AVF).Methods Totally 65 patients with chronic renal failure and suspected AVF stenosis who underwent upper limb CTA were prospectively enrolled and randomly divided into conventional-dose group(CD group,n=30)and low-dose group(LD group,n=35).In CD group,CTA was acquired using conventional tube voltage(100 kVp)and contrast agents dosage(1.0 ml/kg body mass),and conventional hybrid iterative reconstruction(HIR)was used to reconstruct images(group A),while in LD group,CTA was collected using 80 kVp and contrast agent dosage of 0.6 ml/kg body mass,and images were reconstructed with HIR(group B)and AIIR(group C),respectively.Then subjective and objective assessment of imaging quality were performed,respectively,the results were compared among groups,while the radiation dose and dosage of contrast agents were compared between CD and LD groups.Results No significant difference of subjective score of imaging quality nor confidence for diagnosing AVF stenosis was found between group A and group C(both P＞0.017),and all the above scores were higher than those in group B(all P＜0.017).Signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of subclavian artery,brachial artery and radial artery in group C were all higher than those in groups A and B(all P＜0.017),while no significant difference of SNR nor CNR was found between group A and B(all P＞0.017).The volume CT dose index,dose length product and dosage of contrast agent in LD group were all lower than those in CD group(all P＜0.001).Conclusion Low tube voltage and low dose contrast agents combined with AIIR in upper limb CTA for displaying AVF could reduce radiation dose and contrast agents dosage under the condition of ensuring imaging quality.

Objective To investigate the attributable risk(AR)of Acinetobacter baumannii(AB)infection in criti-cally ill patients.Methods A multicenter retrospective cohort study was conducted among adult patients in inten-sive care unit(ICU).Patients with AB isolated from sterile body fluid and confirmed with AB infection in each cen-ter were selected as the infected group.According to the matching criteria that patients should be from the same pe-riod,in the same ICU,as well as with similar APACHE Ⅱ score(±5 points)and primary diagnosis,patients who did not infect with AB were selected as the non-infected group in a 1:2 ratio.The AR was calculated.Results The in-hospital mortality of patients with AB infection in sterile body fluid was 33.3％,and that of non-infected group was 23.1％,with no statistically significant difference between the two groups(P=0.069).The AR was 10.2％(95％CI:-2.3％-22.8％).There is no statistically significant difference in mortality between non-infected pa-tients and infected patients from whose blood,cerebrospinal fluid and other specimen sources AB were isolated(P＞0.05).After infected with AB,critically ill patients with the major diagnosis of pulmonary infection had the high-est AR.There was no statistically significant difference in mortality between patients in the infected and non-infec-ted groups(P＞0.05),or between other diagnostic classifications.Conclusion The prognosis of AB infection in critically ill patients is highly overestimated,but active healthcare-associated infection control for AB in the ICU should still be carried out.

Tricuspid regurgitation(TR)is a common heart valve disease.According to the pathogenesis,TR can be divided into primary(organic)and secondary(functional)regurgitation,of which functional TR accounts for more than 90%.Patients with severe TR have poor prognosis and poor drug treatment,and surgery(valvuloplasty)is the main treatment.At present,transcatheter edge-to-edge tricuspid valve repair(T-TEER)has become an essential program of transcatheter treatment for TR,providing minimally invasive treatment for TR patients who cannot undergo surgery or are at high risk of surgery.T-TEER reduces the degree of regurgitation by clamping leaflets,and is currently in the early stage of research and development exploration and clinical validation,mainly for functional TR.T-TEER devices have also made significant progress(TriClip,PASCAL),and Chinese-made novel-designed T-TEER devices are also undergoing clinical trials(DragonFly-TTM,SQ-Kyrin-TTM,NeoBlazarTM).This paper reviews the current applications and research progress of T-TEER.

Transcatheter aortic valve replacement(TAVR)is currently one of the main therapeutic strategies for aortic valve disease.Preoperative imaging assessment is crucial for operation project planning and prevention of procedure-associated complications.Different from planar image reconstruction,3D printing technology can accurately depict the anatomical structure of the aortic root.It enables further assessment of operative risk and therapeutic strategy through in vitro simulation,especially for assessing the risk of coronary artery obstruction and planning interventional procedures.Here,we report on two patients who underwent a 3D printing aortic root anatomical simulation model,followed an by in vitro balloon dilatation/valve implantation test,to evaluate the risk of coronary artery obstruction suggested by CT angiography planar image reconstruction before TAVR.

Objective:To preparation TREM2-specific monoclonal antibodies and to evaluation their properties and applica-tions lay a foundation for the development of druggable antibodies against TREM2 targets.Methods:The GST fusion protein containing the extracellular segment of TREM2 was expressed and purified,which was used as antigen to immunize mice.The mouse with high antiserum titer was used to generate specific monoclonal antibodies against TREM2 through cell fusion and monoclonal screening.The specificity and affinity of the monoclonal antibodies and their applications in different immunological experiments were detected.Results:A total of 29 strains of anti-TREM2 monoclonal antibodies were obtained,of which 24 strains could specifically bind to TREM2.The EC50 of antibodies were calculated above nanomolar.These monoclonal antibodies could be used for specific detection of TREM2 in Western blot,immunoprecipitation,flow cytometry and immunofluorescence experiments.Conclusion:Monoclonal anti-bodies against TREM2 with high affinity and specificity are successfully generated,which lay the foundation for the research and the development of antibody drugs targeting TREM2.

Objective To observe the efficacy and safety of Morinda officinalis oligosaccharides in the continuation treatment of mild and moderate depression.Methods An open,single-arm,multi-center design was adopted in our study.Adult patients with mild and moderate depression who had received acute treatment of Morinda officinalis oligosaccharides were enrolled and continue to receive Morinda officinalis oligosaccharides capsules for 24 weeks,the dose remained unchanged during continuation treatment.The remission rate,recurrence rate,recurrence time,and the change from baseline to endpoint of Hamilton Depression Scale(HAMD),Hamilton Anxiety Scale(HAMA),Clinical Global Impression-Severity(CGI-S)and Arizona Sexual Experience Scale(ASEX)were evaluated.The incidence of treatment-related adverse events was reported.Results The scores of HAMD-17 at baseline and after treatment were 6.60±1.87 and 5.85±4.18,scores of HAMA were 6.36±3.02 and 4.93±3.09,scores of CGI-S were 1.49±0.56 and 1.29±0.81,scores of ASEX were 15.92±4.72 and 15.57±5.26,with significant difference(P＜0.05).After continuation treatment,the remission rate was 54.59％(202 cases/370 cases),and the recurrence rate was 6.49％(24 cases/370 cases),the recurrence time was(64.67±42.47)days.The incidence of treatment-related adverse events was 15.35％(64 cases/417 cases).Conclusion Morinda officinalis oligosaccharides capsules can be effectively used for the continuation treatment of mild and moderate depression,and are well tolerated and safe.

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status. Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785 participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed. Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953-0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05). Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future.