A novel correction method for modelling parameter-driven autocorrelated time series with count outcome.

BACKGROUND: Count time series (e.g., daily deaths) are a very common type of data in environmental health research. The series is generally autocorrelated, while the widely used generalized linear model is based on the assumption of independent outcomes. None of the existing methods for modelling parameter-driven count time series can obtain consistent and reliable standard error of parameter estimates, causing potential inflation of type I error rate. METHODS: We proposed a new maximum significant ρ correction (MSRC) method that utilizes information of significant autocorrelation coefficient ρ estimate within 5 orders by moment estimation. A Monte Carlo simulation was conducted to evaluate and compare the finite sample performance of the MSRC and classical unbiased correction (UB-corrected) method. We demonstrated a real-data analysis for assessing the effect of drunk driving regulations on the incidence of road traffic injuries (RTIs) using MSRC in Shenzhen, China. Moreover, there is no previous paper assessing the time-varying intervention effect and considering autocorrelation based on daily data of RTIs. RESULTS: Both methods had a small bias in the regression coefficients. The autocorrelation coefficient estimated by UB-corrected is slightly underestimated at high autocorrelation (≥ 0.6), leading to the inflation of the type I error rate. The new method well controlled the type I error rate when the sample size reached 340. Moreover, the power of MSRC increased with increasing sample size and effect size and decreasing nuisance parameters, and it approached UB-corrected when ρ was small (≤ 0.4), but became more reliable as autocorrelation increased further. The daily data of RTIs exhibited significant autocorrelation after controlling for potential confounding, and therefore the MSRC was preferable to the UB-corrected. The intervention contributed to a decrease in the incidence of RTIs by 8.34% (95% CI, -5.69-20.51%), 45.07% (95% CI, 25.86-59.30%) and 42.94% (95% CI, 9.56-64.00%) at 1, 3 and 5 years after the implementation of the intervention, respectively. CONCLUSIONS: The proposed MSRC method provides a reliable and consistent approach for modelling parameter-driven time series with autocorrelated count data. It offers improved estimation compared to existing methods. The strict drunk driving regulations can reduce the risk of RTIs.

The Effectiveness of National Expanded Program on Immunization With Hepatitis A Vaccines in the Chinese Mainland: Interrupted Time-Series Analysis.

BACKGROUND: The high prevalence of hepatitis A delivered a blow to public health decades ago. The World Health Organization (WHO) set a goal to eliminate viral hepatitis including hepatitis A by 2030. In 2008, hepatitis A vaccines were integrated into the Expanded Program on Immunization (EPI) in China to alleviate the burden of hepatitis A, although the effectiveness of the EPI has not been well investigated. OBJECTIVE: We aimed to evaluate the intervention effect at both provincial and national levels on the incidence of hepatitis A in the Chinese mainland from 2005 to 2019. METHODS: Based on the monthly reported number of hepatitis A cases from 2005 to 2019 in each provincial-level administrative division, we adopted generalized additive models with an interrupted time-series design to estimate province-specific effects of the EPI on the incidence of hepatitis A among the target population (children aged 2-9 years) from 2005 to 2019. We then pooled province-specific effect estimates using random-effects meta-analyses. We also assessed the effect among the nontarget population and the whole population. RESULTS: A total of 98,275 hepatitis A cases among children aged 2-9 years were reported in the Chinese mainland from 2005 to 2019, with an average annual incidence of 5.33 cases per 100,000 persons. Nationally, the EPI decreased the hepatitis A incidence by 80.77% (excess risk [ER] -80.77%, 95% CI -85.86% to -72.92%) during the study period, guarding an annual average of 28.52 (95% empirical CI [eCI] 27.37-29.00) cases per 100,000 persons among the target children against hepatitis A. Western China saw a more significant effect of the EPI on the decrease in the incidence of hepatitis A among the target children. A greater number of target children were protected from onset in Northwest and Southwest China, with an excess incidence rate of -129.72 (95% eCI -135.67 to -117.86) and -66.61 (95% eCI -67.63 to -64.22) cases per 100,000 persons on average, respectively. Intervention effects among nontarget (ER -32.88%, 95% CI -39.76% to -25.21%) and whole populations (ER -31.97%, 95% CI -39.61% to -23.37%) were relatively small. CONCLUSIONS: The EPI has presented a lasting positive effect on the containment of hepatitis A in the target population in China. The EPI's effect on the target children also provided a degree of indirect protection for unvaccinated individuals. The continuous surveillance of hepatitis A and the maintenance of mass vaccination should shore up the accomplishment in the decline of hepatitis A incidence to ultimately achieve the goal set by the WHO.

Impact of urbanization on morbidity of hepatitis A: a national panel study in China during 2005-2018.

BACKGROUND: The effect of urbanization on the morbidity of hepatitis A remains unclear. We aimed to estimate the association between various urbanization-related indices and hepatitis A morbidity in China. METHODS: Data on the annual morbidity of hepatitis A, urbanization-related measures (i.e., gross domestic product per capita, the number of hospitalization beds per 1000 persons, illiteracy rate, tap water coverage, motor vehicles per 100 persons, population density, and the proportion of arable land), and meteorological factors in 31 provincial-level administrative divisions of Chinese mainland during 2005-2018 were collected from the National Population and Health Science Data Sharing Platform, China Statistical Yearbooks, and the China Meteorological Data Sharing Service System, respectively. Generalized linear mixed models were applied to quantify the impacts of different urbanization-related indices on the morbidity of hepatitis A in China after adjusting for covariates. RESULTS: A total of 537,466 hepatitis A cases were reported in China during 2005-2018. The annual morbidity had a decline of 79.4% from 5.64 cases to 1.16 cases per 100,000 people. There were obvious spatial variations with higher morbidity in western China. Nationally, gross domestic product per capita and the number of hospitalization beds per 1000 persons increased from 14,040 to 64,644 CNY and from 2.45 to 6.03 during 2005-2018, respectively. The illiteracy rate decreased from 11.0 to 4.9%. Gross domestic product per capita [relative risk (RR) = 0.96, 95% confidence interval (CI): 0.92-0.99], and the number of hospitalization beds per 1000 persons (RR = 0.79, 95% CI: 0.75-0.83) were associated with the declined morbidity of hepatitis A. By contrast, the increased morbidity of hepatitis A was linked to the illiteracy rate (RR = 1.04, 95% CI: 1.02-1.06). Similar influential factors were detected for children and adults, with greater effects witnessed for children. CONCLUSIONS: People in the western region suffered the heaviest burden of hepatitis A in Chinese mainland. Nationally, there was a sharp decline in the morbidity of hepatitis A. The urbanization process was associated with the reduction of hepatitis A morbidity in China during 2005-2018.

Helicobacter pylori and gastric microbiota homeostasis: progress and prospects.

Helicobacter pylori, a Gram-negative microaerobic bacteria belonging to the phylum Proteobacteria, can colonize in the stomach and duodenum, and cause a series of gastrointestinal diseases such as gastritis, gastric ulcer and even gastric cancer. At present, the high diversity of the microorganisms in the stomach has been confirmed with culture-independent methods; some researchers have also studied the stomach microbiota composition at different stages of H. pylori carcinogenesis. Here, we mainly review the possible role of H. pylori-mediated microbiota changes in the occurrence and development of gastric cancer to provide new ideas for preventing H. pylori infection and regulating microecological imbalance.

Roles of microRNAs and exosomes in Helicobacter pylori associated gastric cancer.

Helicobacter pylori (H. pylori) is a common pathogen that infects more than half of the world's population. Its infection can not only lead to a variety of gastrointestinal diseases, such as chronic gastritis and gastric cancer (GC) but also be associated with many extra-gastrointestinal diseases. Exosomes, as a new intercellular information transmission medium, can carry biological signal molecules such as microRNAs (miRNAs) to regulate a variety of cellular physiological activities and are involved in multiple cancer processes. In this article, we provide a systematic review on the role of exosomal miRNAs in H. pylori-associated GC.

Using ketamine in a patient with a near-occlusion tracheal tumor undergoing tracheal resection and reconstruction: A case report.

BACKGROUND: Tracheal tumors may cause airway obstruction and pose a significant risk to ventilation and oxygenation. Due to its rarity, there is currently no established protocol or guideline for anesthetic management of resection of upper tracheal tumors, therefore individualized strategies are necessary. There are limited number of reports regarding the anesthesthetic management of upper tracheal resection and reconstruction (TRR) in the literature. We successfully used intravenous ketamine to manage a patient with a near-occlusion upper tracheal tumor undergoing TRR. CASE SUMMARY: A 25-year-old female reported progressive dyspnea and hemoptysis. Bronchoscopy showed an intratracheal tumor located one tracheal ring below the glottis, which occluded > 90% of the tracheal lumen. The patient was scheduled for TRR. Considering the risk of complete airway collapse after the induction of general anesthesia, we decided to secure the airway with a tracheostomy with spontaneous breathing. The surgeons needed to transect the trachea 1-2 cartilage rings below and above the tumor borders: a time-consuming process. Coughing and movement needed be minimized; thus, we added intravenous ketamine to local anesthetic infiltration. After tracheostomy, an endotracheal tube was placed into the distal trachea, and general anesthesia was induced. The surgeons resected four cartilage rings with the tumor attached and anastomosed the posterior tracheal wall. We performed a video-laryngoscopy to place a new endotracheal tube. Finally, the surgeons anastomosed the anterior tracheal walls. The patient was extubated uneventfully. CONCLUSION: Ketamine showed great advantages in the anesthesia of upper TRR by providing analgesia with minimal respiratory depression or airway collapse.

[Association of Perioperative Allogeneic Red Blood Cell Transfusion with Postoperative Infections].

Allogeneic red blood cell transfusion can induce transfusion-related immunomodulation while correcting anemia and improving oxygenation,and thus may be associated with the increased risk of postoperative infections.However,the available studies have conflicting conclusions.Preclinical studies demonstrate transfusion-related immunomodulation is associated with transfusion amounts.Stored red blood cells can cause more significant immunosuppression than fresh blood products,while leukoreduction alleviates the negative effect on immune system.However,clinical studies do not reach agreements on these issues.Recently,accumulating multi-center,large-sample-size,real-world studies have reported significant associations of all ogeneic red blood cell transfusion in cardiac,orthopedic,hepatic,pancreatic,gastrointestinal,and vesical surgeries with postoperative infections.Considering the limitations of previous studies,future research should focus on multiple operations,prolong the time interval between transfusion and surgery,include different infections into outcomes,and define the postoperative infections accurately in the premise of adequate samples.High-quality clinical evidence could help to optimize the utilization of blood products and improve the postoperative outcomes.

Biological functions and potential therapeutic applications of huntingtin-associated protein 1: progress and prospects

Huntington disease (HD) is a single-gene autosomal dominant inherited neurodegenerative disease caused by a polyglutamine expansion of the protein huntingtin (HTT). Huntingtin-associated protein 1 (HAP1) is the first protein identified as an interacting partner of huntingtin, which is directly associated with HD. HAP1 is mainly expressed in the nervous system and is also found in the endocrine system and digestive system, and then involves in the occurrence of the related endocrine diseases, digestive system diseases, and cancer. Understanding the function of HAP1 could help elucidate the pathogenesis that HTT plays in the disease process. Therefore, this article attempts to summarize the latest research progress of the role of HAP1 and its application for diseases in recent years, aiming to clarify the functions of HAP1 and its interacting proteins, and provide new research ideas and new therapeutic targets for the treatment of cancer and related diseases.

Biological functions and potential therapeutic applications of huntingtin-associated protein 1: progress and prospects.

Huntington disease (HD) is a single-gene autosomal dominant inherited neurodegenerative disease caused by a polyglutamine expansion of the protein huntingtin (HTT). Huntingtin-associated protein 1 (HAP1) is the first protein identified as an interacting partner of huntingtin, which is directly associated with HD. HAP1 is mainly expressed in the nervous system and is also found in the endocrine system and digestive system, and then involves in the occurrence of the related endocrine diseases, digestive system diseases, and cancer. Understanding the function of HAP1 could help elucidate the pathogenesis that HTT plays in the disease process. Therefore, this article attempts to summarize the latest research progress of the role of HAP1 and its application for diseases in recent years, aiming to clarify the functions of HAP1 and its interacting proteins, and provide new research ideas and new therapeutic targets for the treatment of cancer and related diseases.

Time-varying effect of drunk driving regulations on road traffic mortality in Guangzhou, China: an interrupted time-series analysis.

BACKGROUND: China has introduced a series of stricter policies to criminalize drunk driving and increase penalties since May 2011. However, there is no previous study examining the time-varying impacts of drunk driving regulations on road traffic fatalities based on daily data. METHODS: We collected 6536 individual data of road traffic deaths (RTDs) in Guangzhou from 2008 to 2018. The quasi-Poisson regression models with an inclusion of the intervention variable and the interaction of intervention variable and a function of time were used to quantify the time-varying effects of these regulations. RESULTS: During the 11-year study period, the number of population and motor vehicles showed a steady upward trend. However, the population- and motor vehicles- standardized RTDs rose steadily before May 2011, the criminalizing drunk driving intervention was implemented and gradually declined after that. The new drunk driving intervention were associated with an average risk reduction of RTDs (ER = -9.01, 95% eCI: - 10.05% to - 7.62%) during the 7.7 years after May 2011. On average, 75.82 (95% eCI, 54.06 to 92.04) RTDs per 1 million population annually were prevented due to the drunk driving intervention. CONCLUSION: These findings would provide important implications for the development of integrated intervention measures in China and other countries attempting to reduce traffic fatalities by stricter regulations on drunk driving.

Trends and seasonality in cause-specific mortality among children under 15 years in Guangzhou, China, 2008-2018.

BACKGROUND: This study analyzed the trends and seasonality in mortality among children aged 0-14 years in Guangzhou, China during 2008-2018. Understanding the epidemiology of this public health problem can guide policy development for children mortality prevention. METHODS: A population-based epidemiological retrospective study was conducted. Seven thousand two hundred sixty-five individual data of children mortality were obtained from the Guangzhou Center for Disease Control and Prevention (CDC). The Poisson regression was used to quantify the annual average reduction rate and the difference in mortality rate between sex and age groups. Incidence ratio with 95% confidence interval (CI) was estimated to determine the temperaol variations in mortality by month, season, school term, day of the week and between holidays and other days. RESULTS: Between 2008 and 2018, the children mortality rate in Guangzhou decreased from 54.0 to 34.3 per 100,000 children, with an annual reduction rate of 4.6% (95% CI: 1.1%-8.1%), especially the under-5 mortality rate decreased by 8.3% (95% CI: 4.8%-11.6%) per year. Decline trends varied by causes of death, even with an upward trend for the mortality of asphyxia and neurological diseases. The risk of death among males children was 1.33 times (95% CI: 1.20-1.47) of that of females. The distribution of causes of death differed by age group. Maternal and perinatal, congenital and pneumonia were the top three causes of death in infants and cancer accounted for 17% of deaths in children aged 1-14 years. Moreover, the injury-related mortality showed significant temporal variations with higher risk during the weekend. And there was a summer peak for drowning and a winter peak for asphyxia. CONCLUSIONS: Guangzhou has made considerable progress in reducing mortality over the last decade. The findings of characteristics of children mortality would provide important information for the development and implementation of integrated interventions targeted specific age groups and causes of death.

Infection Prevention Strategy in Operating Room during Coronavirus Disease 2019 (COVID-19) Outbreak.

A novel coronavirus that emerged in late 2019 rapidly spread around the world. Most severe cases need endotracheal intubation and mechanical ventilation, and some mild cases may need emergent surgery under general anesthesia. The novel coronavirus was reported to transmit via droplets, contact and natural aerosols from human to human. Therefore, aerosol-producing procedures such as endotracheal intubation and airway suction may put the healthcare providers at high risk of nosocomial infection. Based on recently published articles, this review provides detailed feasible recommendations for primary anesthesiologists on infection prevention in operating room during COVID-19 outbreak.

[Perioperative Restrictive Red Blood Cell Transfusion:Recent Advances in Research and Clinical Guidelines].

Perioperative restrictive red blood cell(RBC)transfusion strategy,in which a trigger of hemoglobin(Hb)<7 g/dl is used,is of great benefits to save blood storage and reduce transfusion-related adverse events including infections,immunologic risks,and circulatory overload.Human body can display a series of compensatory mechanisms to acute anemia,including increased cardiac output,favored oxyhemoglobin dissociation,and lung vascular dilation.Therefore,moderate Hb decrease does not necessarily lead to hypoxemia.Patients undergoing hip surgery or suffering from septic shock and/or upper gastrointestinal bleeding can benefit from restrictive RBC transfusion;however,restrictive transfusion may be associated with adverse outcomes in patients with coronary heart disease or undergoing cardiac surgery.Restrictive RBC transfusion strategies have been included in described in many different guidelines.Most of them recommended Hb<7 g/dl to be a trigger for allogeneic RBC transfusion.For patients with an Hb of 7-10 g/dl,the application of restrictive RBC transfusion should be based on the expected blood loss,compensatory ability,and metabolic rate.

Evaluation of the implementation rate of primary antifungal prophylaxis and the prognosis of invasive fungal disease in acute leukemia patients in China.

BACKGROUND: Invasive fungal disease (IFD) is a major complication of acute leukemia, thus primary antifungal prophylaxis (PAP) is recommended by guidelines. Nevertheless, guidelines might not be commonly followed in developing countries due to economic factors. The primary objectives were to evaluate the implementation rate of PAP in acute leukemia patients in China and to compare the prognosis of IFD with and without PAP. The secondary objectives were to investigate the safety of PAP, clinical characteristics of IFDs and risk factors of breakthrough. METHODS: This was a retrospective observational single-center study, including non-M3 acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) patients receiving uniform induction or salvage chemotherapy between 2012 and 2016. RESULTS: There were 29.4% of patients without PAP among a total of 248 cases. The incidence of breakthrough proven/probable/possible IFDs was 24.7%, 6.5%, 5.5%, 5.4% and 5.3% in control (no prophylaxis), fluconazole, itraconazole, voriconazole and posaconazole group respectively (P = 0.007), while the percentage of patients requiring empirical or pre-emptive therapy was 54.8%, 45.7%, 23.3%, 18.9%, 10.5% respectively (P < 0.001). PAP could also significantly improve IFD-free survival (P < 0.001) and reduce 90-day overall mortality in patients on AML salvage regimen (P = 0.021). There were no statistical differences in PAP-related adverse events. Past history of IFD (OR 9.5, P = 0.006) was confirmed to be independent risk factors. CONCLUSIONS: There are a considerable number of acute leukemia patients without PAP in China, who have higher IFD incidence, increased empiric/pre-emptive antifungal drug use and worse IFD-free survival.

Valsartan Protects Against Contrast-Induced Acute Kidney Injury in Rats by Inhibiting Endoplasmic Reticulum Stress-Induced Apoptosis.

BACKGROUND AND OBJECTIVE: Contrast-induced acute kidney injury (CI-AKI) is a serious complication of the administration of iodinated contrast media (CM) for diagnostic and interventional cardiovascular procedures and is associated with substantial morbidity and mortality. While the preventative measures can mitigate the risk of CI-AKI, there remains a need for novel and effective therapeutic approaches. The pathogenesis of CI-AKI is complex and not completely understood. CM-induced renal tubular cell apoptosis caused by the activation of endoplasmic reticulum (ER) stress is involved in CIAKI. We previously demonstrated that valsartan alleviated CM-induced human renal tubular cell apoptosis by inhibiting ER stress in vitro. However, the nephroprotective effect of valsartan on CI-AKI in vivo has not been investigated. Therefore, the aim of this study was to explore the protective effect of valsartan in a rat model of CI-AKI by measuring the amelioration of renal damage and the changes in ER stressrelated biomarkers. METHOD AND RESULTS: Our results showed that the radiocontrast agent meglumine diatrizoate caused significant renal insufficiency, renin-angiotensin system (RAS) activation, and renal tubular apoptosis by triggering ER stress through activation of glucose-regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), caspase 12, CCAAT/enhancer-binding protein-homologous protein (CHOP) and c-Jun N-terminal protein kinase (JNK) (P<0.05; n=6 in each group). Pre-treatment with valsartan significantly alleviated renal dysfunction, pathological injury, and apoptosis along with the inhibition of ER stressrelated biomarkers (P<0.05; n=8 in each group). CONCLUSION: Valsartan could protect against meglumine diatrizoate-induced kidney injury in rats by inhibiting the ER stress-induced apoptosis, making it a promising strategy for preventing CI-AKI.

HJB-1, a 17-hydroxy-jolkinolide B derivative, inhibits LPS-induced inflammation in mouse peritoneal macrophages.

Jolkinolide B (JB) and 17-hydroxy-JB (HJB) are diterpenoids from plants and it has been reported that the presence of a C-17 hydroxy group in JB significantly enhances the anti-inflammatory potency of JB. In this study, two HJB derivatives HJB-1 and HJB-2 were generated by the chemical modification of a 17-hydroxy group of HJB. HJB-1 more effectively inhibited TNF-α, IL-1ß and IL-6 release in LPS-stimulated mouse peritoneal macrophages. In addition, HJB-1 reduced LPS-induced mRNA expression of TNF-α, IL-1ß, IL-6, COX-2 and iNOS in a concentration-dependent manner, but did not alter IL-10 mRNA expression. LPS-induced NF-κB activation and MAPK phosphorylation were also effectively inhibited by HJB-1. These results demonstrate that HJB-1 exerts anti-inflammatory effects on LPS-activated mouse peritoneal macrophages by inhibiting NF-κB activation and MAPK phosphorylation and modification of a 17-hydroxy group of HJB may enhance the anti-inflammatory potency of HJB derivatives.

[Effects of trimetazidine therapy on left ventricular function after percutaneous coronary intervention].

OBJECTIVE: To explore the effects of trimetazidine therapy on left ventricular (LV) function after percutaneous coronary intervention (PCI). METHODS: A total of 106 patients with unstable angina pectoris underwent successful elective PCI were randomly assigned to standard therapy group (control, n = 55) or trimetazidine group (n = 51, 60 mg trimetazidine loading dose prior to PCI followed by 20 mg Tid after PCI on top of standard therapy). cTnI level was measured before and at 16-18 hours after PCI. LV function was evaluated by echocardiography and major adverse cardiac events (MACE, including death, re-infarction and target vessel revascularization) at 12 months after PCI was compared between the two groups. RESULTS: Post procedural cTnI level increased from [0.02 (0.01, 0.03)] µg/L at baseline to [0.11 (0.07, 0.13)] µg/L (P < 0.05) at 16-18 hours in the trimetazidine group, while [0.02(0.01, 0.03)] µg/L to [1.31(0.44, 2.31)] µg/L in the control group (P < 0.05). Post procedural cTnI level was significantly reduced in the trimetazidine group compared to the control group (P < 0.05). At 12 months follow-up, left ventricular ejection fraction in the trimetazidine group was significantly higher than in control group [(65.65 ± 3.94)% vs. (62.29 ± 3.06)%, P < 0.01] while incidence of MACE was similar between the two groups. CONCLUSION: Trimetazidine can reduce the post-PCI cTnI release and improve left ventricular function after PCI in patients with unstable angina pectoris.

Impact of chronic obstructive pulmonary diseases on outcomes and hospital days after percutaneous coronary intervention.

Chronic obstructive pulmonary disease (COPD) is common in patients undergoing percutaneous coronary intervention (PCI), but the impact of COPD on outcomes after PCI has received limited attention. Consecutive patients with coronary heart disease (n = 5155) undergoing PCI were enrolled in this study; 645 patients (73% men) aged 68.4 ± 13.2 years had COPD and 4510 patients (71% men) aged 64.7 ± 12.1 years did not. During the in-hospital period after PCI, the patients with COPD experienced a significantly higher incidence of angina (P < .001), arrhythmias (P < .001), and composite major adverse cardiac events (MACEs; P < .001) and longer hospital stay (P < .001) than those without COPD. Additionally, severity of COPD (measured by pulmonary function tests) was associated with increased composite MACE (P < .001) and hospital stay (P < .001) after PCI. In conclusion, COPD is associated with significantly increased composite MACE and hospital stay in patients after PCI. Increasing severity of COPD is associated with increased composite MACE and hospital stay after PCI.

Assessment of early radial injury after transradial coronary intervention by high-resolution ultrasound biomicroscopy: innovative technology application.

BACKGROUND: Transradial coronary intervention (TRI) introduces injury to the radial artery (RA) which will affect repeat transradial coronary procedure and the quality as a bypass conduit. We sought to compare the early radial injury after TRI between first-TRI and repeat-TRI by ultrasound biomicroscopy (UBM). METHODS: A total of 1116 patients who underwent the transradial coronary procedures were enrolled. The patients depending on whether for the first time to accept transradial coronary procedure were divided into first-TRI group and repeat-TRI group. The RA was examined by UBM before and one day after the procedure. RESULTS: Compared with first-TRI group, the mean RA diameter of repeat-TRI one day after the procedure decreased significantly (P < 0.05). In first-TRI group, the mean RA diameter was (2.32 ± 0.53) and (1.93 ± 0.57) mm before procedure and one day after the procedure respectively (P < 0.05). In repeat-TRI group, the mean RA diameter was (2.37 ± 0.51) and (1.79 ± 0.54) mm before procedure and one day after the procedure, respectively (P < 0.01). Compared with first-TRI group, the mean RA diameter was reduced significantly in repeat-TRI group one day after the procedure (P < 0.05). The early radial injuries and intimal thickening were compared between first-TRI and repeat-TRI. The mean intima-media thickness of RA was (0.24 ± 0.13) mm and (0.59 ± 0.28) mm before procedure and one day after the procedure in first-TRI group. The mean intima-media thickness of RA was (0.29 ± 0.16) mm and (0.68 ± 0.32) mm before procedure and one day after the procedure in repeat-TRI group. Compared with first-TRI group, the mean intimal thickening was increased significantly in repeat-TRI group one day after the procedure (P < 0.05). Intimal dissection, stenosis and occlusion were all significantly greater in repeat-TRI RAs (P < 0.05). Linear regression analysis revealed that diameter, repeated TRI procedure and PCI procedure were the independent predictors of intimal thickening. CONCLUSIONS: RA early injuries were greater in repeat-TRI patients than in first-TRI patients. We first use high-resolution UBM imaging to demonstrate the rate of radial injury and revealed that diameter, repeated TRI procedure and PCI procedure were the independent predictors of intimal thickening.