[Induction of peripheral blood mononuclear cells to hepatocyte-like cells and preliminary study of cell response to injury under the effect of acetaminophen]

Objective: To establish a method for the induction of peripheral blood mononuclear cells to hepatocyte-like cells, and preliminarily investigate cell response to injury under the effect of acetaminophen (APAP). Methods: The surface marker CD45 of peripheral blood mononuclear cells wase detected cells by using flow cytometry and immunofluorescence methods. The cellular morphology of induced hepatocyte-like cells was observed under an inverted microscope. Real-time fluorescent quantitative PCR (RT-PCR) was used to detect the expression level of hepatocyte-specific genes, such as cytochrome (CY) P1A2, CYP3A4, CYP2C9, albumin (ALB), alpha-fetoprotein (AFP), and hepatocyte nuclear factor (HNF)4α mRNA. Immunofluorescence method was used to detect intracellular hepatocyte markers AFP, HNF4α, and ALB expression at the protein level. Biochemical analyzer was used to detect hepatocyte-specific secretory functions of AFP, ALB, and urea. Luciferase chemiluminescence method was used to detect the activity of key drug metabolizing enzyme CYP3A4. Colorimetric assay was used to detect the effect of the drug acetaminophen on hepatocyte-like cells, and alanine aminotransferase (ALT) was used as an indicator of liver cell injury. The statistical differences between the data were compared with t-test and rank-sum test. Results: The positive expression rate of CD45 cell surface markers isolated from peripheral blood mononuclear cells was about 98%, and hepatocyte-like cell morphology changes appeared on 15th day of induction. Compared with isolated mononuclear cells, CYP1A2, CYP3A4, CYP2C9, ALB, AFP and HNF4α mRNA was markedly elevated. The expression level of AFP, ALB and HNF4α protein were equally increased, and the secretory function of AFP, ALB and urea were enhanced. Compared with primary hepatocytes, CYP1A2, CYP2C9, AFP, HNF4α mRNA, and CYP3A4 mRNA did not decrease. The expression levels of AFP, ALB, and HNF4α proteins in the cells did not decrease, and the secretory function of AFP, ALB, and urea did not decrease. In addition, the CYP3A4 enzyme activity produced by hepatocyte-like cells was similar to that of primary hepatocytes. Compared with hepatocyte-like cells incubated without APAP, hepatocyte-like cells incubated with APAP had higher ALT level. Under the effect of APAP, the ALT level of hepatocyte-like cells was higher than isolated mononuclear cells. Conclusion: Peripheral blood mononuclear cells can be induced into hepatocyte-like cells with partial characteristics of hepatocytes, including the activity of CYP3A4, a key enzyme of hepatocyte drug metabolism. Additionally, preliminarily ALT secretory features reflect the hepatocytes injury under the effect of acetaminophen.

Correlation of Four Single Nucleotide Polymorphisms of the RELN Gene With Schizophrenia

OBJECTIVE

This study aims to determine the association between single-nucleotide polymorphisms (SNPs) of the RELN gene and schizophrenia.

METHODS

134 patients aged 16 to 58 (mean, 38.0) years who were diagnosed with acute or chronic schizophrenia at the Zhongshan Third People's Hospital between January 2018 and April 2020 were recruited, as were 64 healthy controls aged 22 to 59 (mean, 45.6) years who matched with the age and sex of the patients. MassARRAY mass spectrometry genotyping technology was used to determine the genotypes of four SNPs of RELN (rs2073559, rs2229864, rs362691, and rs736707).

RESULTS

There were no significant between-group or between-sex differences in terms of genotype, allele frequency, or haplotype frequency of the SNPs (all p > 0.05). In the association analysis between genotypes and quantitative traits in the Positive and Negative Syndrome Scale, rs2229864 and rs736707 were associated with the scores for items P3 (hallucinatory behaviour) and G11 (attention disorder), and rs362691 was associated with G10 (disorientation). However, the associations did not remain significant after Bonferroni correction.

CONCLUSION

Multiple pathogenic polymorphisms of RELN might be associated with hallucinatory behaviour and attention disorder in Chinese patients with schizophrenia.

Risk of herpesvirus, serious, and opportunistic infections in atopic dermatitis: a population-based cohort study

BACKGROUND

Staphylococcal and herpes simplex virus (HSV) infections are commonly recognized in atopic dermatitis (AD) but less is known about other types of infections.

OBJECTIVES

To determine the risk of herpesvirus infections, serious infections, and opportunistic infections in patients with AD.

METHODS

We conducted a population-based cohort study using UK-based electronic medical records data. Patients with AD were each matched to up to 5 unaffected patients on age, practice, and index date. AD severity was defined using treatments. The outcomes were incident herpesvirus infections (cytomegalovirus [CMV], Epstein-Barr virus [EBV], HSV, or varicella zoster virus [VZV]), serious infections, and opportunistic infections.

RESULTS

409,431 children and 625,083 adults with AD were matched to 1,809,029 children and 2,678,888 adults without AD, respectively. In adjusted Cox regression models, children and adults with AD had 50-52% greater risk of HSV and 18-33% greater risk of VZV, with risk increasing in parallel with AD severity. CMV risk was elevated among children with AD (HR 2.50 [1.38-4.54]) and adults with severe AD (4.45 [1.76-11.25]). Patients with AD had 26-40% increase in risk of serious infections, with severe AD carrying greatest risk. Although rare, opportunistic infections were not associated with AD in children but were associated with all severities of AD in adults (overall HR 1.31 [1.20-1.42]). All estimates remained consistent after excluding patients receiving immunosuppressive treatments for AD.

CONCLUSIONS

AD is significantly associated with herpesvirus infections, serious infections, and opportunistic infections in a dose-responsive manner with severity. AD may increase susceptibility to infections exclusive of immunosuppressive medications.

Adipose-derived exosomes impairs endothelial transient receptor potential vanilloid 4 channels and elevates blood pressure in abdominal obesity

Aim

Large epidemiological studies have found that abdominal obesity is a strong risk factor for hypertension. Impaired endothelium-dependent vasodilation is a hallmark of obesity-induced hypertension. Adipose-derived exosomes can regulate distant tissues as novel adipokines, providing a new mechanism for cell-cell interactions. However, the effects of adipose-derived exosomes on obesity-induced hypertension are unknown.

Methods

We extracted three adipose-derived exosomes, including high-fat diet (HFD) mouse serum exosome, adipose tissue exosome, and adipose-derived stem cell exosome, and further explored their effects on endothelium-dependent vasodilation in vivo and in vitro.

Results

Impairment of endothelial transient receptor potential vanilloid 4 (TRPV4) channel activity and vasodilation were observed in the arteries from abdominal obesity patients. Ca2+ influx through TRPV4 channels at myoendothelial projections to smooth muscle cells decreases resting blood pressure in nonobese mice, a response that is diminished in HFD mice. Administration of three exosomes elevated blood pressure by promoting artery endothelial barrier permeability, impairing the expression of adherens junctions, and aggravating inflammatory response in vivo and in vitro, accompanied by TRPV4/Ca2+ pathway inhibition.

Conclusions

Impairment of endothelial TRPV4 channels contributes to obesity-induced hypertension and imply that HFD-induced obesity plays a role in blood pressure by aggravating the artery endothelial barrier injury and inflammatory response via adipose-derived exosomes, at least partially, through inhibiting the TRPV4/Ca2+ pathway.

Funding Acknowledgement

Type of funding sources: None. Main funding source(s): This research was supported by grants from the National Natural Science Foundation of China (81970262) (P.J.W.), Innovation Team Project Department of Education of Sichuan Province (18TD0030) (PJW), Central Funds Guiding the Local Science and Technology Development of Sichuan Province (2020ZYD036, P.W.), and grants from the Scientific Research Fund of Chengdu Medical College (CYZYB20-07) (J.W.).

[Five-step maneuver of transthoracic single-port assisted laparoscopic lower mediastinal lymph node dissection for Siewert type Ⅱ adenocarcinoma of the esophagogastric junction]

Objective: Surgical operation is the main treatment for advanced adenocarcinoma of esophagogastric junction (AEG). Due to its special anatomic location and unique lymph node reflux mode, the surgical treatment of Siewert II AEG is controversial. Lower mediastinal lymph node dissection is one of the most controversial points and a standard technique has not yet been established. This study is aim to explore the safety and feasibility of five-step maneuver of transthoracic single-port assisted laparoscopic lower mediastinal lymph node dissection for Siewert type II AEG. Methods: A descriptive case series study was conducted. The intraoperative and postoperative data of 25 patients with Siewert type II AEG who underwent five-step maneuver of transthoracic single-port assisted laparoscopic lower mediastinal lymph node dissection in Guangdong Provincial Hospital of Traditional Chinese Medicine from January 2019 to April 2021 were retrospectively analyzed. Five-step maneuver was as follows: In the first step, the subcardiac sac was exposed; the right pulmonary ligament lymph nodes and the anterior thoracic paraaortic lymph nodes were dissected cranial to inferior pericardium, left to left edge of thoracic aorta. In the second step, the left diaphragm was opened, and a 12 mm trocar was placed through the 6-7 rib in the left anterior axillary line. The supra-diaphragmatic nodes were dissected through the thoracic operation hole. In the third step, the left inferior pulmonary ligament was severed. The anterior fascia of thoracic aorta was incised to join the anterior space of thoracic aorta formed in the first step and then the lymphatic tissue was dissected upward until the exposure of left inferior pulmonary vein. In the fourth step, the posterior pericardium was denuded retrogradely from ventral side to oral side to the level of left inferior pulmonary vein, right to right pleura, and then the right pulmonary ligament lymph nodes were completely removed. In the fifth step, the esophagus was denuded, and the esophagus was transected 5 cm above the tumor using a linear stapler to complete the dissection of lower thoracic paraesophageal lymph nodes. Results: Operations were successfully completed in 25 patients without conversion, intra-operative complication and perioperative death. Total gastrectomy was performed in 19 cases and proximal gastrectomy in 6 cases. The mean operative time was (268.7±85.6) minutes, the mean estimated blood loss was (90.4±44.2) ml, the mean time of lower mediastinal lymph node dissection was (38.6±10.3) minutes, and the mean harvested number of lower mediastinal lymph node was 5.9±2.9. The length of esophageal invasion was >2 cm in 7 cases and ≤ 2 cm in 18 cases. Eight patients (33.0%) had lower mediastinal lymph node metastasis, including 3 cases with esophageal invasion >2 cm and 5 cases with esophageal invasion ≤ 2 cm. The mean time to postoperative first flatus was (5.5±3.1) days. The average time of postoperative thoracic drainage was (5.9±2.9) days. The mean hospital stay was (9.7±3.1) days. Two patients (8.0%) developed postoperative grade IIIa complications according to the Clavien-Dindo classification, including 1 case of pancreatic fistula and 1 case of pleural effusion, both of whom were cured by puncture drainage. Conclusions: Five-step maneuver of transthoracic single-port assisted laparoscopic lower mediastinal lymph nodes dissection for Siewert type II AEG is safe and feasible. Which can ensure sufficient lower mediastinal lymph node dissection to the level of left inferior pulmonary vein.

[Role of Bruton's tyrosine kinase in endotoxin/lipopolysaccharide-induced pyroptosis of intestinal cells in scalded mice]

Objective: To investigate the role of Bruton's tyrosine kinase (BTK) in pyroptosis of intestinal cells caused by endotoxin/lipopolysaccharide (LPS) in scalded mice. Methods: The experimental research method was applied. One hundred and twenty-eight male C57BL/6 mice aged 6-8 weeks were divided into sham injury group, scald alone group, scald+LPS group, scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group. There were 8 mice in sham injury group, and there were 24 mice in the other 5 groups, respectively. Mice in 5 scald groups were inflicted with 10% total body surface area full-thickness scald on the back, and mice in sham injury group were sham injured on the back. At post injury hour (PIH) 0 (immediately), mice in sham injury group and scald alone group were intraperitoneally injected with normal saline, mice in scald+LPS group were intraperitoneally injected with LPS, and mice in scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group were intraperitoneally injected with LPS and LFM-A13 in corresponding doses. Mice in sham injury group were sacrificed at PIH 0 to collect serum and intestinal tissue, and 8 mice in each group of 5 scald groups were sacrificed at PIH 0, 12, and 24 to collect intestinal tissue and serum at PIH 12. Immunohistochemistry was used to detect phosphorylation of BTK in intestinal tissue of mice. Western blotting was used to detect the protein expressions of phosphorylated BTK (p-BTK), cleaved cysteine aspartic acid specific protease 1 (caspase-1), and cleaved caspase-11 in intestinal tissue of mice. Enzyme-linked immunosorbent assay method was used to detect interleukin-1β (IL-1β) in serum and intestinal tissue of mice. Data were statistically analyzed with one-way analysis of variance and least significant difference test. Results: There was no obvious phosphorylation of BTK in intestinal tissue of mice in 6 groups at PIH 0 and scald alone group at PIH 12 and 24. Phosphorylation of BTK in intestinal tissue of mice in scald+LPS group at PIH 12 and 24 were obviously increased compared with those in scald alone group. Phosphorylation of BTK in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group, scald+LPS+10 mg/kg LFM-A13 group, and scald+LPS+30 mg/kg LFM-A13 group were obviously decreased compared with those in scald+LPS group, and the degrees of decline gradually increased with increase of dose in LFM-A13. Compared with (0.130±0.010) of sham injury group and (0.120±0.040 and 0.110±0.040) of scald alone group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS group at PIH 12 and 24 were obviously increased (0.470±0.090 and 0.430±0.080, P<0.01). Compared with those in scald+LPS group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group at PIH 24, and scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased (0.280±0.060, 0.300±0.120, 0.150±0.050, 0.280±0.090, 0.140±0.040, P<0.05 or P<0.01). Compared with those in scald+LPS+3 mg/kg LFM-A13 group, protein expressions of p-BTK in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 24 were obviously decreased (P<0.01). Compared with those in sham injury group and scald alone group, protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS group were obviously increased at PIH 12 and 24 (P<0.01). Compared with those in scald+LPS group, protein expressions of cleaved caspase-1 at PIH 12 and cleaved caspase-11 at PIH 12 and 24 in intestinal tissue of mice in scald+LPS+3 mg/kg LFM-A13 group and protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased (P<0.01). Compared with those in scald+LPS+3 mg/kg LFM-A13 group, protein expressions of cleaved caspase-1 and caspase-11 in intestinal tissue of mice in scald+LPS+10 mg/kg LFM-A13 group and scald+LPS+30 mg/kg LFM-A13 group at PIH 12 and 24 were obviously decreased (P<0.05 or P<0.01). At PIH 12, content of IL-1β in intestinal tissue and serum of mice in scald+LPS group were obviously higher than those in sham injury group and scald alone group (P<0.01), and content of IL-1β in intestinal tissue and serum of mice in scald+LPS+30 mg/kg LFM-A13 group were obviously lower than those in scald+LPS group (P<0.01). Conclusions: Phosphorylation of BTK is related to increases of cleaved caspase-1 and caspase-11 in intestinal tissue, and IL-1β content in intestinal tissue and serum of scalded septic mice caused by LPS. Phosphorylation of BTK mediates intestinal cell pyroptosis of scalded mice caused by LPS. Inhibiting phosphorylation of BTK can alleviate intestinal cell pyroptosis of scalded mice, with protective effect on intestinal injury intestine.

986 A Systematic Review of Medical Student Willingness to Volunteer and Preparedness for Pandemics and Disasters

Introduction

We aimed to identify motivators and barriers to volunteering during a disaster and knowledge and medical school curriculum of disaster and pandemic medicine.

Method

We systematically searched the literature on 28/6/2020, following PRISMA guidelines.

Results

A total of 37 studies met inclusion criteria including 11,168 medical students and 91 medical schools. 24 studies evaluated knowledge (64.9%), 16 evaluated volunteering (43.2%), and five evaluated medical school curricula (13.5%). Weighted mean willingness to volunteer during a disaster was 68.4% (SD = 21.7%, n = 2911), and there was a significant difference between those planning to volunteer and those who actually volunteered (P<.001). We identified a number of modifiable barriers which may contribute to this difference. Overall, knowledge of disasters was poor with a weighted mean of 48.9% (SD = 15.1%, n = 2985).

Conclusions

There is a large number of students who are willing to volunteer during pandemics. However, they are likely to be under-prepared for these roles due to poor overall knowledge and limited teaching. During the current COVID-19 pandemic and in future disasters, medical students may be required to volunteer as auxiliary staff. Medical schools need to develop infrastructure to facilitate this process as well as providing education and training to ensure students are adequately prepared for these roles.

967 COVID READY Study: Cross-Sectional Survey of Medical Students Volunteering During the Coronavirus Pandemic (COVID-19) In the United Kingdom

Introduction

We aimed to identify the willingness, attitudes, and practice of medical students towards volunteering in a clinical capacity during the COVID-19 pandemic.

Method

We distributed a cross-sectional survey from 2/5/2020 to 14/6/2020 to all medical students at UK medical schools.

Results

A total of 1145 medical students from 36 medical schools completed the questionnaire. 82.7% of students were willing to volunteer, but only 34.3% had volunteered. The strongest predictors of willingness to volunteer on multiple linear regression were the beliefs that volunteering to work would benefit their medical education (estimate=0.35±0.03, adjusted P < 0.001) and that they would have a positive impact (estimate=0.33±0.03, adjusted P < 0.001). The majority of students were willing to take up a clinical role and were confident in having the necessary skills, but there was a discrepancy between the role’s students were comfortable performing and those they were assigned. Thematic analysis of the issue’s students would face when volunteering identified five themes: safety, professional practice, pressure to volunteer, finances and logistics, and education.

Conclusions

This study identifies areas for consideration from those responsible for workforce planning, healthcare provision, and student safety. We provide recommendations to facilitate a volunteering process that is safer for students, staff, and patients.

[Efficacy observation of the caudal-medial approach combined with "page-turning" middle lymphadenectomy in the laparoscopic right hemicolectomy]

Objective: To investigate the safety and feasibility of caudal-medial approach combined with "page-turning" middle lymphadenectomy in the laparoscopic right hemicolectomy. Methods: A descriptive cohort study was conducted. Clinical data of 35 patients who underwent laparoscopic radical right hemicolectomy using caudal-medial approach combined with "page-turning" middle lymphadenectomy at Department of Gastrointestinal Surgery, Guangdong Hospital of Chinese Medicine from April 2018 to May 2020 were retrospectively analyzed. All operations were performed consecutively by the same surgeon. The caudal-medial approach was used to dissect the right Toldt's fascia and the anterior pancreaticoduodenal space in a caudal-to-cranial and medial-to-lateral manner guided by the duodenum. The "page-turning" middle lymphadenectomy was used to dissect the mesocolon along the superior mesenteric vein with ileocolic vein, Henle's trunk and pancreas exposed preferentially. Results: All the 35 patients completed the operation successfully, and there was no damage and bleeding of superior mesenteric vessels and their branches. The operative time was (186.9±46.2) minutes, and the blood loss was 50 (10-200) ml. The first time to flatus was (2.1±0.6) days, and the time to fluid intake was (2.5±0.8) days. The postoperative hospital stay was 6 (3-18) d. The overall morbidity of postoperative complication was 8.6% (3/35), including grade II in 1 cases (2.8%) and grade IIIa in 2 case (5.7%) according to the Clavien-Dindo grading standard. The total number of lymph node dissected was 30.2±5.6, and the positive lymph node was 0 (0-7). Tumor staging revealed 5 cases of stage I, 18 cases of stage II, 11 cases of stage III, and 1 case of stage IVA. In this study, the median follow-up time was 15 (4-29) months. One patient died due to cerebrovascular accident 12 months after surgery, and no tumor recurrence or metastasis was observed in all other patients. Conclusions: Laparoscopic radical right hemicolectomy using caudal-medial approach combined with "page-turning" middle lymphadenectomy is safe and feasible. The anterior pancreaticoduodenal space is preferentially mobilized, which reduces the difficulty of central vascular dissection.

Defining heart disease risk for death in COVID-19 infection

BACKGROUND

Cardiovascular disease (CVD) was in common in coronavirus disease 2019 (COVID-19) patients and associated with unfavorable outcomes. We aimed to compare the clinical observations and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected patients with or without CVD.

METHODS

Patients with laboratory-confirmed SARS-CoV-2 infection were clinically evaluated at Wuhan Seventh People's Hospital, Wuhan, China, from 23 January to 14 March 2020. Demographic data, laboratory findings, comorbidities, treatments and outcomes were collected and analyzed in COVID-19 patients with and without CVD.

RESULTS

Among 596 patients with COVID-19, 215 (36.1%) of them with CVD. Compared with patients without CVD, these patients were significantly older (66 vs. 52 years) and had higher proportion of men (52.5% vs. 43.8%). Complications in the course of disease were more common in patients with CVD, included acute respiratory distress syndrome (22.8% vs. 8.1%), malignant arrhythmias (3.7% vs. 1.0%) including ventricular tachycardia/ventricular fibrillation, acute coagulopathy(7.9% vs. 1.8%) and acute kidney injury (11.6% vs. 3.4%). The rate of glucocorticoid therapy (36.7% vs. 25.5%), Vitamin C (23.3% vs. 11.8%), mechanical ventilation (21.9% vs. 7.6%), intensive care unit admission (12.6% vs. 3.7%) and mortality (16.7% vs. 4.7%) were higher in patients with CVD (both P < 0.05). The multivariable Cox regression models showed that older age (≥65 years old) (HR 3.165, 95% CI 1.722-5.817) and patients with CVD (HR 2.166, 95% CI 1.189-3.948) were independent risk factors for death.

CONCLUSIONS

CVD are independent risk factors for COVID-19 patients. COVID-19 patients with CVD were more severe and had higher mortality rate, early intervention and vigilance should be taken.

[Detection of right-to-left shunt with transthoracic contrast echocardiography in patients with pulmonary hypertension]

Objective: To explore the value of right heart contrast echocardiography in etiological diagnosis and severity assessment of pulmonary hypertension (PH). Methods: A retrospective analysis was conducted on 74 patients who underwent transthoracic contrast echocardiography in China-Japan Friendship Hospital from May 2015 to July 2018, all of whom were diagnosed as PH by right heart catheterization. Patients were divided into three groups according to contrast echocardiography: the intra-cardiac shunt group (<4 cardiac cycles with microbubbles in the left heart); Intrapulmonary shunt group (>4 cardiac cycles with microbubbles in the left heart); non-shunt group. The etiology, partial arterial oxygen pressure (PO(2)), N-terminal pro-brain natriuretic peptide (NT-proBNP), mean pulmonary artery pressure (mPAP), right atrial pressure (RAP), pulmonary vascular resistance (PVR) and cardiac output (CO) were analyzed. Central nervous system complications were also compared among the three groups. Results: Among the 74 patients, right-to-left shunt was found in 28 cases (37.8%) by contrast echocardiography, including 11 cases (14.9%) of intra-cardiac shunt and 17 cases (23.0%) of intrapulmonary shunt. In the 11 cases of intra-cardiac shunt, 7 were diagnosed with congenital heart disease and 4 were patent foramen. Two with hereditary hemorrhagic telangiectasia (HHT) and 1 with pulmonary arteriovenous malformation (PAVM) were included in the 16 cases of intrapulmonary shunt. There was no statistical difference in PO(2), mPAP, PVR, NT-proBNP, RAP, CO and functional class among the three groups (all P>0.05). A total of 5 cases (6.8%) were found with nervous system comorbidities, 4 cases (5.4%) with cerebral infarction and 1 cases epilepsy, and 2 cases of cerebral infarction were diagnosed as paradoxical embolism. Nervous system complications were more common in patients with intra-cardiac shunt than in other groups. Conclusion: While right-to-left shunt detected by contrast echocardiography has no relationship with disease severity, it has complementary value in the etiological diagnosis of PH, and intra-cardiac shunt may increase the risk of nervous system complications.

[Risk factors and clinical features of hospital-associated venous thromboembolism]

Objective: To investigate the clinical features and risk factors of hospital-associated venous thromboembolism (VTE). Methods: The study enrolled acute VTE patients admitted into China-Japan Friendship Hospital from January 1, 2017 to December 31, 2017. The hospital-associated VTE (HA-VTE) group and the community-associated VTE (CA-VTE) group were classified according to whether the VTE occurred during hospitalization or within a 90-day period of admission to hospital (including inpatient with at least two days of hospital stay or a surgical procedure under general or regional anaesthesia). Differences in clinical features, risk factors, and mortality rate were compared between the two groups. Results: A total of 437 patients with acute VTE were analyzed in the study. Among them, 266 patients were HA-VTE, 171 patients were CA-VTE. Patients in the CA-VTE group were more likely to have varicose veins, sedentary, long-distance travel, and patients in the HA-VTE group were more complicated with recent surgery (<1 month), bed rest, active malignant tumor, acute infections, acute cerebral infarction, fracture, central venous catheter (P<0.05). The CA-VTE group had more clinical symptoms such as lower extremity pain, dyspnea, chest pain and chest tightness (P<0.05). HA-VTE patients had less clinical symptoms but were more severe than the CA-VTE patients, with more sudden deaths (0 vs 3.4%, P=0.035). Among HA-VTE patients, 92.8% experienced VTE during hospitalization or within 1 month of the preceding hospital encounter, with a 13-day median time to VTE. The all-cause mortality rate was higher for HA-VTE group than CA-VTE group (8.3% vs 1.2%, P<0.001), and the in-hospital VTE was more common compared to VTE diagnosed post-discharge (12.2% vs 3.4%, P<0.001). Conclusions: More than half events of VTE are related to recent hospitalizations. HA-VTE has different risk factors from CA-VTE, combined with fewer clinical symptoms but higher all-cause mortality rate. More attention about VTE should be paid to hospitalized patients to reduce the incidence of HA-VTE events.

[Efficacy and safety of Balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension]

Objective: To study the efficacy and safety of Balloon pulmonary angioplasty (BPA) for chronic thromboembolic pulmonary hypertension (CTEPH). Methods: Patients who were diagnosed CTEPH in China-Japan Friendship Hospital from Feb 2018 to Sep 2019 were evaluated. The ineligibility for pulmonary endarterectomy (PEA) and the indication for BPA were decided on the basis of a consensus among the multidisciplinary team for all CTEPH patients. 6-min walk distance (6MWD), the plasma level of N-terminal pro-brain natriuretic peptide (NT-proBNP), mixed venous oxygen saturation, mean pulmonary artery pressure (mPAP), cardiac index (CI) and pulmonary vascular resistance (PVR) were collected and analyzed before the first and the last BPA session. Results: A total of 67 BPA sessions were performed for 302 subsegmental pulmonary arteries in 25 inoperable CTEPH patients. 10 males (40.0%) and 15 females (60.0%), with the age of (57.8±7.1) years old. The median interval between CTEPH diagnosis and first BPA was 20.0 (9.0, 48.5) months. 18 patients were received more than 2 BPA sessions, the median follow-up time was 5.0 (3.5, 8.3) months. 6MWD, CI and the mixed venous oxygen saturation were significant improved after BPA [(425±74) vs (345±109) m, (1.99±0.45) vs (1.62±0.35) L·min(-1)·m(-2), (68.1%±6.5%) vs (61.2%±6.3%)](all P<0.05). The plasma level of NT-proBNP, mPAP and PVR were significantly decreased after BPA [259 (93, 739) vs 806 (148, 2 159) ng/L, (40.6±8.3) vs (47.3±10.7) mmHg (1 mmHg=0.133 kPa), (11.9±4.9) vs (17.2±6.5) WU (1 WU=80 dyn·s·cm(-5))](all P<0.05). Hemoptysis occurred in 5 sessions (7.5%) and reperfusion pulmonary edema (RPE) occurred in 2 sessions (1.5%), 1 patient needed non-invasive mechanical ventilation because of RPE, 1 patient died from right heart failure caused by hemoptysis during perioperative period. Conclusions: BPA can significantly improve the exercise tolerance and hemodynamic parameters for inoperable CTEPH patients, the risks of BPA are acceptable. BPA is an effective and relatively safe treatment for inoperable CTEPH patients.

[Clinical characteristics of patients with chronic thromboembolic pulmonary hypertension]

Objective: To investigate the clinical characteristics of patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: CTEPH cases consecutively admitted into China-Japan Friendship Hospital from September 2015 to June 2019 were enrolled with prospective data collection. The medical histories, clinical characteristics, laboratory tests, imaging manifestation and hemodynamic parameters were analyzed. Patients were divided into high pulmonary vascular resistance (PVR) group and low PVR group according to the PVR level>1 000 dyn·s·cm(-5) or not, and clinical characteristics were compared between these two groups. Results: In the 148 cases of CTEPH, right heart catheterization was performed in 103 cases with mPAP (45.1±11.0) mmHg and PVR of (992±430) dyn·s·cm(-5). At diagnosis, 88 (59.5%) cases were in WHO functional class Ⅲ and 27 (18.2%) in class Ⅳ. Most common presenting symptoms were dyspnea (147, 99.3%), chest tightness (68, 45.9%), hemoptysis (42, 28.3%), syncope (30, 20.3%), and most common signs were P2 accentuation (95, 64.9%), edema (65, 43.9%), cyanosis (47, 31.8%), systolic murmur (44, 29.7%) and jugular vein distention (35, 23.6%). In 103 cases with right heart catheterization, 52 were in the low PVR group and 51 in high PVR group. Compared to the low PVR group, high PVR group patients had higher WHO functional class and more jugular vein distention (both P<0.05). In all the 148 cases, previous venous thromboembolism (VTE) was confirmed in 105 (70.9%) patients, with a higher prevalence of previous VTE in low PVR group than that in high PVR group (P<0.001). 30 (20.3%) patients had varicose veins of the lower extremities, and 21 (14.2%) had other thrombophilic disorders including antiphospholipid syndrome, protein C and S deficiency and antithrombin Ⅲ deficiency. Conclusions: Dyspnea, P2 accentuation and edema are the most common clinical presentation of CTEPH. Previous history of VTE is common in CTEPH patients with thrombophilia in some cases.

[Brain protection strategy and effectivity in pulmonary thromboendarterectomy]

Objective: To summarize the experience and effectivity of brain protection in 25 patients who suffered from chronic thromboembolic pulmonary hypertension (CTEPH) and received pulmonary thromboendarterectomy (PTE) under deep hypothermic circulatory arrest. Methods: Retrospective analysis of 25 PTE surgeries in our center from December 2016 to August 2018. All cases were completed underdeep hypothermic circulatory arrest. Standard brain protections were strictly executed, including: balanced and controlled extracorporeal circulation cooling, cerebral oxygen saturation (rSO(2)) monitoring, strictly control of circulatory arrest time, and etc. The neurological adverse events during the perioperative period were recorded and statistically analyzed, and the intelligence level and cognitive function of the patients were evaluated by MMSE scale and MoCA scale before surgery and discharge. Results: All the 25 patients successfully completed the surgery, and 1 patient (4%) died of postoperative infection. The mean pulmonary arterial pressure decreased from (52.9±16.7) mmHg before surgery to (23.6±8.1) mmHg immediately after surgery (t=10.01, P<0.01), and(20.7±7.9) mmHg at 3 months follow-up (t=10.73, P<0.01). Pulmonary vascular resistance decreased from 975.4 (788.6-1 292.8) dyn·s·cm(-5) to 376.1 (283.6-565.5) dyn·s·cm(-5) (Z=5.34, P<0.01). Neurological complications occurred in 3 patients during the perioperative period, including 2 patients with hypoxic encephalopathy, and 1 patient with cerebral hemorrhage. All 3 patients fully recovered before discharge. Univariate analysis showed that the duration of rSO(2)<40% and the maximum decrease rate of rSO(2) from baseline were significantly correlated with postoperative neurological damage. Multivariate analysis showed only time of rSO(2)<40% was significantly correlated with postoperative neurological damage. There was no significant difference in MMSE and MoCA score before and after surgery (P>0.05). Conclusions: Adequate brain protection measures are essential to reduce the neurological complications of PTE surgery. Real-time intraoperative monitoring of rSO(2) and strict control of circulatory arrest time can further reduce the occurrence of neurological damage.