Paediatric/young versus adult patients with congenital long QT syndrome or catecholaminergic polymorphic ventricular tachycardia

Introduction

Congenital long QT syndrome (LQTS) and catecholaminergic ventricular tachycardia (CPVT) are less prevalent cardiac ion channelopathies than Brugada syndrome in Asia. The present study compared paediatric/young and adult patients with these conditions.

Method

This was a territory-wide retrospective cohort study of consecutive patients diagnosed with congenital LQTS and CPVT attending public hospitals in Hong Kong. The primary outcome was spontaneous ventricular tachycardia/ventricular fibrillation (VT/VF).

Results

A total of 142 congenital LQTS (mean onset age= 27±23 years old) and 16 CPVT (mean presentation age=11±4 years old) patients were included. For congenital LQTS, arrhythmias other than VT/VF (HR=4.67, 95% confidence interval = [1.53–14.3], p=0.007), initial VT/VF (HR=3.25 [1.29–8.16], p=0.012) and Schwartz score (HR=1.90 [1.11–3.26], p=0.020) were predictive of the primary outcome for the overall cohort, whilst arrhythmias other than VT/VF (HR=5.41 [1.36–21.4], p=0.016) and Schwartz score (HR=4.67 [1.48–14.7], p=0.009) were predictive for the adult subgroup (>25 years old; n=58). All CPVT patients presented before the age of 25 but no significant predictors of VT/VF were identified. A random survival forest model identified initial VT/VF, Schwartz score, initial QTc interval, family history of LQTS, initially asymptomatic, and arrhythmias other than VT/VF as the most important variables for risk prediction in LQTS, and initial VT/VF/sudden cardiac death, palpitations, QTc, initially symptomatic and heart rate in CPVT.

Conclusion

Clinical and ECG presentation vary between the pediatric/young and adult congenital LQTS population. All CPVT patients presented before the age of 25. Machine learning models achieved more accurate VT/VF prediction.

Funding Acknowledgement

Type of funding sources: None. Kaplan-Meier survival curve for LQTSKaplan-Meier survival curve for CPVT

A model of lifetime health outcomes in cardiovascular disease based on clinical trials and large cohorts

Background and purpose

Cardiovascular disease (CVD) risk of individuals depends on their socio-demographic characteristics, clinical risk factors, and treatments, and strongly influences their quality of life and survival. Individual-based long-term disease models, which aim to more accurately calculate the lifetime consequences, can help to target treatments, develop disease management programmes, and assess the value of new therapies. We present a new micro-simulation CVD model.

Methods

This micro-simulation model was developed using individual participant data from the Cholesterol Treatment Trialists' collaboration (CTT: 118,000 participants; 15 trials) and calibrated (with added socioeconomic deprivation, ethnicity, physical activity, mental illness, cancer and incident diabetes) in the UK Biobank cohort (UKB: 502,000 participants). Parametric survival models estimated risks of key endpoints (myocardial infarction (MI), stroke, coronary revascularisation (CRV), diabetes, cancer and vascular (VD) and nonvascular death (NVD) using participants' age, sex, ethnicity, physical activity, socioeconomic deprivation, smoking history, lipids, blood pressure, creatinine, previous cardiovascular diseases, diabetes, mental illness and cancer at entry and non-fatal incidents of the key endpoints during follow-up. The model integrates the risk equations and enables annual projection of endpoints and survival over individuals' lifetimes. The model was used to project remaining life expectancy across UK Biobank participants.

Results

Nonfatal cardiovascular events and age were the major determinants of CVD risk and, together with incident diabetes and cancer, of individuals' survival. The cumulative incidence of the key endpoints predicted by the CTT-UKB model corresponded well to their observed incidence in the UK Biobank cohort, overall (Figure 1) and in categories of participants by age, sex, prior CVD and CVD risk. Predicted remaining life expectancy across UK Biobank participants without history of CVD ranged between 22 and 43 years in men and between 24 and 46 years in women, depending on their age and CVD risk (Figure 2). Among UK Biobank participants with history of CVD, depending on their age, predicted remaining life expectancy ranged from 20 to 32 years in men and from 26 to 38 years in women.

Conclusion

This new lifetime CVD model accurately predicts morbidity and mortality in a large UK population cohort. It will be made available to provide individualised projections of expected lifetime health outcomes and benefits of treatments.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme, UK Medical Research Council (MRC), British Heart Foundation Figure 1. Predicted (in black) versus observed (95% CI; in red) incidence of major clinical outcomes in the UK Biobank.Figure 2. Predicted remaining life expectancy of participants in UK Biobank cohort, by age and CVD risk or previous CVD at entry. QRISK, a 10-year CVD risk scoring algorithm for people without previous CVD, recommended for use in the UK National Health Service.

Derivation of an electronic frailty index for short-term mortality in heart failure: a machine learning approach

Objective

Frailty may be found in heart failure patients especially in the elderly and is associated with a poor prognosis. However, assessment of frailty status is time-consuming and the electronic frailty indices developed using health records have served as useful surrogates. We hypothesized that an electronic frailty index developed using machine learning can improve short-term mortality prediction in patients with heart failure.

Methods

This was a retrospective observational study included patients admitted to nine public hospitals for heart failure from Hong Kong between 2013 and 2017. Age, sex, variables in the modified frailty index, Deyo's Charlson comorbidity index (≥2), neutrophil-to-lymphocyte ratio (NLR) and prognostic nutritional index (PNI) were analyzed. Gradient boosting, which is a supervised sequential ensemble learning algorithm with weak prediction submodels (typically decision trees), was applied to predict mortality. Variables were ranked in the order of importance with a total score of 100 and used to build the predictive models. Comparisons were made with decision tree and multivariate logistic regression.

Results

A total of 8893 patients (median: age 81, Q1-Q3: 71–87 years old) were included, in whom 9% had 30-day mortality and 17% had 90-day mortality. PNI, age and NLR were the most important variables predicting 30-day mortality (importance score: 37.4, 32.1, 20.5, respectively) and 90-day mortality (importance score: 35.3, 36.3, 14.6, respectively). Gradient boosting significantly outperformed decision tree and multivariate logistic regression (area under the curve: 0.90, 0.86 and 0.86 for 30-day mortality; 0.92, 0.89 and 0.86 for 90-day mortality).

Conclusions

The electronic frailty index based on comorbidities, inflammation and nutrition information can readily predict mortality outcomes. Their predictive performances were significantly improved by gradient boosting techniques.

Funding Acknowledgement

Type of funding sources: None.

A territory-wide study of arrhythmogenic right ventricular cardiomyopathy patients from Hong Kong

Background

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a hereditary disease characterised by fibrofatty infiltration of the right ventricular myocardium that predisposes affected patients to malignant ventricular arrhythmias, dual-chamber cardiac failure and sudden cardiac death (SCD).

Methods

This was a territory-wide retrospective cohort study of patients diagnosed with ARVC/D between 1997 and 2019. The primary outcome was incident ventricular tachycardia/ventricular fibrillation (VT/VF). The secondary outcomes were new-onset heart failure with reduced ejection fraction (HFrEF) and all-cause mortality.

Results

This study consisted of 115 ARVC/D patients (median age: 60 [44.1–70.2] years; 58% male). Of these, 51 and 24 patients developed incident VT/VF and new-onset HFrEF, respectively. Five patients underwent cardiac transplantation, and 14 died during follow-up. Multivariate Cox regression identified prolonged QRS duration as a predictor of VT/VF (P<0.05). Female gender, prolonged QTc duration, the presence of epsilon waves and T-wave inversion (TWI) in any lead except aVR/V1 predicted new-onset HFrEF (P<0.05). Female gender, prolonged QTc duration and the presence of epsilon waves, in addition to the parameters of older age at diagnosis of ARVC/D, prolonged QRS duration and worsening ejection fraction predicted all-cause mortality (p<0.05). Clinical scores were also developed to predict new-onset HFrEF (Table 1a-c) and all-cause mortality (Table 2a-c). This was followed by the application of a non-parametric machine learning survival analysis models for outcome prediction. These machine learning algorithms better capture nonlinear and interactive patterns within survival data compared to traditionally used Cox regression models, which assume the existence of a hazard function between survival data and censored outcomes. The present study introduced weighted random survival forests models for the prediction of incident VT/VF, HFrEF and all-cause mortality. Findings indicate that these machine learning wRSF models performed the best in the prediction of all three aforementioned outcomes compared to other analytical methods.

Conclusion

Clinical and electrocardiographic parameters are important for assessing prognosis in ARVC/D patients. Machine learning algorithms appear to be the most optimal tools for event prediction, and as such should potentially be used to aid risk stratification and decision-making in the clinical setting.

Funding Acknowledgement

Type of funding sources: None.

Prevalence and impact of metabolic syndrome in patients with multivessel coronary artery disease and acute coronary syndrome

Background

Metabolic syndrome is associated with increased incidence of diabetes and cardiovascular diseases in patients initially free from these diseases. However, its prognostic value in patients with established coronary artery diseases remains controversial.

Purpose

Therefore, we aimed to illustrate the prevalence and investigate the impact of metabolic syndrome in patients with multivessel coronary artery disease and acute coronary syndrome.

Methods

We conducted a large registry of consecutive patients with acute coronary syndrome referred to primary percutaneous coronary intervention and those with multivessel diseases were eligible for this analysis. Metabolic syndrome was defined using modified criteria based on the Adult Treatment Panel III definition from the National Cholesterol Education Program. The primary outcome was major adverse cardiovascular events (MACE), a composite of all-cause death, myocardial infarction, and stroke.

Results

A total of 2532 patients were included in current analysis and 993 (39.2%) of them had metabolic syndrome while 1539 (60.8%) did not. The prevalence of metabolic syndrome increased over the study period (p for trend = 0.005). There was a significant decline of metabolic syndrome prevalence in patients over 60 years old (p for trend = 0.002) and females had a higher prevalence than their male counterparts (61.5% verse 32.9%, p<0.001). Over a median follow-up of 2.3 years, metabolic syndrome was not significantly associated with MACE (adjusted 95% CI 0.92 to 1.54). In addition, there was no significant difference observed between two groups in other individual outcomes, namely all-cause death, cardiac death, stroke, myocardial infarction, and any revascularization.

Conclusions

Metabolic syndrome was frequently observed in patients with multivessel coronary artery disease and acute coronary syndrome. Patients with metabolic syndrome were more likely to be young and female. However, it was not an independent predictor for MACE after primary percutaneous coronary intervention in those patients.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences Metabolic syndrome distribution in MVDOutcome according to metabolic syndrome

Tributyrin supplementation in pasteurized waste milk: Effects on growth performance, health, and blood parameters of dairy calves

This study evaluated the effects of incremental tributyrin supplementation in pasteurized waste milk on growth performance, health, and blood metabolism of dairy calves before and after weaning. Forty-eight newborn female Holstein dairy calves (39.6 ± 2.75 kg; mean ± standard deviation) were blocked by age and randomly assigned to 3 treatments: pasteurized waste milk (1) without supplementation, (2) with 1 g/L of tributyrin products (unprotected solid powder; containing 35% tributyrin), or (3) with 2 g/L of tributyrin products. The calves were weaned on d 56 and were raised until d 77. Data were analyzed for the preweaning, postweaning, and overall periods. The results showed that starter intake and hay intake were not different among treatments in any period of the trial, but the crude protein intake tended to increase linearly with tributyrin supplementation during the overall period. Although tributyrin supplementation had no effects on body weight during preweaning and overall periods, body weight increased linearly with tributyrin supplementation postweaning. The average daily gain tended to increase linearly during postweaning and overall periods. No effects were observed on feed efficiency in any period. A positive linear relationship between body length and tributyrin supplementation was observed during the postweaning period, but no differences were found for the other body structural measurements in any period. The results of diarrhea showed that tributyrin concentration had a negative linear relationship with diarrhea frequency during preweaning and overall periods. The rectal temperature did not differ among treatments in any period, but a treatment × week effect for rectal body temperature was observed. For blood metabolism, tributyrin supplementation had no effects on insulin, growth hormone, total protein, albumin, or globulin. No differences were found in serum amyloid A concentration in any of the periods, yet haptoglobin concentration decreased linearly with increasing tributyrin concentration during postweaning and overall periods. Endothelin concentration showed a tendency to decrease linearly during preweaning and postweaning periods and decreased linearly with tributyrin supplementation during the overall period. An increasing tributyrin concentration was associated with a negative linear relationship with IL-1β concentration during the preweaning period, and no differences were found in the other periods. The concentration of IL-6 and tumor necrosis factor α were not different among treatments in any of the periods. These data suggest that increasing the concentration of tributyrin in pasteurized waste milk could increase growth performance and health of dairy calves, and incremental tributyrin supplementation could linearly reduce haptoglobin, endothelin, and IL-1β concentrations, indicating a positive effect of tributyrin on alleviating oxidative stress and inflammatory status of dairy calves. Calves fed pasteurized waste milk supplemented with tributyrin products (containing 35% tributyrin) at 2 g/L compared with 1 g/L of milk had more improved growth and health.

[Effect of splenectomy on the risk of hepatocellular carcinoma development among patients with liver cirrhosis and portal hypertension: a multi-institutional cohort study]

Objective: To identify whether splenectomy for treatment of hypersplenism has any impact on development of hepatocellular carcinoma(HCC) among patients with liver cirrhosis and hepatitis. Methods: Patients who underwent splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension between January 2008 and December 2012 were included from seven hospitals in China, whereas patients receiving medication treatments for liver cirrhosis and portal hypertension (non-splenectomy) at the same time period among the seven hospitals were included as control groups. In the splenectomy group, all the patients received open or laparoscopic splenectomy with or without pericardial devascularization. In contrast, patients in the control group were treated conservatively for liver cirrhosis and portal hypertension with medicines (non-splenectomy) with no invasive treatments, such as transjugular intrahepatic portosystemic shunt, splenectomy or liver transplantation before HCC development. All the patients were routinely screened for HCC development with abdominal ultrasound, liver function and alpha-fetoprotein every 3 to 6 months. To minimize the selection bias, propensity score matching (PSM) was used to match the baseline data of patients among splenectomy versus non-splenectomy groups. The Kaplan-Meier method was used to calculate the overall survival and cumulative incidence of HCC development, and the Log-rank test was used to compare the survival or disease rates between the two groups. Univariate and Cox proportional hazard regression models were used to analyze the potential risk factors associated with development of HCC. Results: A total of 871 patients with liver cirrhosis and hypertension were included synchronously from 7 tertiary hospitals. Among them, 407 patients had a history of splenectomy for hypersplenism (splenectomy group), whereas 464 patients who received medical treatment but not splenectomy (non-splenectomy group). After PSM,233 pairs of patients were matched in adjusted cohorts. The cumulative incidence of HCC diagnosis at 1,3,5 and 7 years were 1%,6%,7% and 15% in the splenectomy group, which was significantly lower than 1%,6%,15% and 23% in the non-splenectomy group (HR=0.53,95%CI:0.31 to 0.91,P=0.028). On multivariable analysis, splenectomy was independently associated with decreased risk of HCC development (HR=0.55,95%CI:0.32 to 0.95,P=0.031). The cumulative survival rates of all the patients at 1,3,5,and 7 years were 100%,97%,91%,86% in the splenectomy group,which was similar with that of 100%,97%,92%,84% in the non-splenectomy group (P=0.899). In total,49 patients (12.0%) among splenectomy group and 75 patients (16.2%) in non-splenectomy group developed HCC during the study period, respectively. Compared to patients in non-splenectomy group, patients who developed HCC after splenectomy were unlikely to receive curative resection for HCC (12.2% vs. 33.3%,χ²=7.029, P=0.008). Conclusion: Splenectomy for treatment of hypersplenism may decrease the risk of HCC development among patients with liver cirrhosis and portal hypertension.

Exosome-mediated transfer of MIF confers temozolomide resistance by regulating TIMP3/PI3K/AKT axis in gliomas

Temozolomide (TMZ) resistance is an important cause of clinical treatment failure and poor prognosis in gliomas. Increasing evidence indicates that cancer-derived exosomes contribute to chemoresistance; however, the specific contribution of glioma-derived exosomes remains unclear. The aim of this study was to explore the role and underlying mechanisms of exosomal macrophage migration inhibitory factor (MIF) on TMZ resistance in gliomas. We first demonstrated that MIF was upregulated in the exosomes of TMZ-resistant cells, engendering the transfer of TMZ resistance to sensitive cells. Our results indicated that exosomal MIF conferred TMZ resistance to sensitive cells through the enhancement of cell proliferation and the repression of cell apoptosis upon TMZ exposure. MIF knockdown enhanced TMZ sensitivity in resistant glioma cells by upregulating Metalloproteinase Inhibitor 3 (TIMP3) and subsequently suppressing the PI3K/AKT signaling pathway. Additionally, exosomal MIF promoted tumor growth and TMZ resistance of glioma cells in vivo, while IOS-1 (MIF inhibitor) promotes glioma TMZ sensitive in vivo. Taken together, our study demonstrated that exosome-mediated transfer of MIF enhanced TMZ resistance in glioma through downregulating TIMP3 and further activating the PI3K/AKT signaling pathway, highlighting a prognostic biomarker and promising therapeutic target for TMZ treatment in gliomas.

[Evaluation of shoulder function after repairing head and neck defects with supraclavicular flap]

Objective: To evaluate the shoulder function in patients after repair of head and neck defects with supraclavicular flap. Methods: A retrospective analysis was performed on 56 patients (54 males, 2 females, aged 35-74 years old) who received the repair of head and neck defects with supraclavicular flaps at Department of Otorhinolaryngology Head and Neck Surgery of Beijing Tongren Hospital, Capital Medical University in January 2013-December 2020. The areas and types of flaps, disruption or infections of the incision at the donor sites and other postoperative complications were recorded. Quick disabilities of the arm, shoulder and hand (Quick-DASH) was used for evaluating the shoulder functions in 43 patients conforming to the standard for evaluation of the clinical functions of shoulders and upper limbs, to compare the postoperative upper limb functions between patients treated with clavicular flaps and patients with acromion flaps. Meanwhile, 30 patients who received bilateral neck lymph node dissection over the same period of time were selected for a comparative evaluation of the donor sides (observation group) and the opposite sides (control group). Data were processed with SPSS 22.0. Results: The areas of obtained supraclavicular flaps were (4-10) cm × (10-18) cm. Three patients (5%) showed the defect widths of 8-10 cm at the donor sites, which couldn't be sutured directly, received the repair of their shoulder defects with partial flaps. Defects in other patients were sutured directly. After surgery, 3 patients (5%) suffered from disruption of the acromion incision, which healed after 2 weeks of local dressing. The follow-up time was 6-43 (27±14) months. All patients expressed no dissatisfaction with the appearance. Among 43 patients, 28 (65%) were clavicular type and 15 (35%) were acromion type. The acromion type showed average motor ability and Quick-DASH scores higher than the clavicular type [(average motor ability: (14.4±4.7) vs. (11.8±3.1), t=2.105, P=0.048; Quick-DASH: (16.9±11.6) vs. (12.2±7.1), t=2.284, P=0.033]. Among 30 patients who received bilateral neck lymph node dissection over the same period of time, the observation group showed higher average motor ability, local symptoms and Quick-DASH scores than the control group [average motor ability: (13.4±5.8) vs. (9.8±4.2), t=3.024, P=0.004; average local symptoms: (4.1±1.0) vs. (3.4±1.0), t=2.537, P=0.014; Quick-DASH: (15.6±14.7) vs. (5.2±11.1), t=3.106, P=0.003]. Conclusion: Shoulder dysfunction exists after treatment with supraclavicular flap, which is related to the flap type.

Effects of isometric resistance exercise of the lower limbs on intraocular pressure and ocular perfusion pressure among healthy adults: A meta-analysis

BACKGROUND

The main risks for glaucoma are increased intraocular pressure (IOP) and decreased ocular perfusion pressure (OPP). This review aims to examine the potential impact of lower limb isometric resistance exercise on intraocular pressure and ocular perfusion pressure.

METHOD

A meta-analysis was conducted to determine the potential impact of isometric exercise on IOP and OPP. The literature on the relationship between isometric resistance exercise and IOP was systematically searched according to the "Cochrane Handbook" in the databases of Pubmed, Web of Science, EBSCO, and Scopus through December 31, 2020. The search terms used were "exercise," "train," "isometric," "intraocular pressure," and "ocular perfusion pressure," and the mean differences of the data were analyzed using the Stata 16.0 software, with a 95% confidence interval.

RESULTS

A total of 13 studies, which included 268 adult participants consisting of 162 men and 106 women, were selected. All the exercise programs that were included were isometric resistance exercises of the lower limbs with intervention times of 1min, 2min, or 6min. The increase in IOP after intervention was as follows: I²=87.1%, P=0.001 using random-effects model combined statistics, SMD=1.03 (0.48, 1.59), and the increase in OPP was as follows: I²=94.5%, P=0.001 using random-effects model combined statistics, SMD=2.94 (1.65, 4.22), with both results showing high heterogeneity.

CONCLUSION

As isometric exercise may cause an increase in IOP and OPP, therefore, people with glaucoma and related high risk should perform isometric exercise with caution.

Genome-wide association study reveals a quantitative trait locus and two candidate genes on Sus scrofa chromosome 5 affecting intramuscular fat content in Suhuai pigs

Intramuscular fat content (IFC) is an essential quantitative trait of meat, affecting multiple meat quality indicators. A certain amount of IFC could not only improve the sensory score of pork but also increase the flavour, tenderness, juiciness and shelf-life. To dissect the genetic determinants of IFC, two methods, including genome-wide efficient mixed-model analysis (GEMMA) and linkage disequilibrium adjusted kinships (LDAKs), were used to carry out genome-wide association studies for IFC in Suhuai pig population. A total of 14 and 18 significant single nucleotide polymorphisms (SNPs) were identified by GEMMA and LDAK, respectively. The results of these two methods were highly consistent and all 14 significant SNPs in GEMMA were detected by LDAK. Seven of the 18 SNPs reached the genome-wide significance level (P < 9.85E-07) while 11 cases reached the suggestive significance level (P < 1.77E-05). These significant SNPs were mainly distributed on Sus scrofa chromosome (SSC) 5, 3, and 7. Moreover, one locus resides in a 2.27 Mb (71.37-73.64 Mb) region on SSC5 harbouring 13 significant SNPs associated with IFC, and the lead SNP (rs81302978) also locates in this region. Linkage disequilibrium (LD) analysis showed that there were four pairs of complete LD (r² = 1) among these 13 SNPs, and the remaining 9 SNPs with incomplete LD (r² ≠ 1) were selected for subsequent analyses of IFC. Association analyses showed that 7 out of 9 SNPs were significantly associated with IFC (P < 0.05) in 330 Suhuai pigs, and the other 2 SNPs tended to reach a significant association level with IFC (P < 0.1). The phenotypic variance explained (PVE) range of these 9 SNPs was 0.92-3.55%. Meanwhile, the lead SNP was also significantly associated (rs81302978) with IFC (P < 0.05) in 378 commercial hybrid pigs (Pietrain × Duroc) × (Landrace × Yorkshire) (PDLY), and the PVE was 1.38%. Besides, two lipid metabolism-relevant candidate genes, the leucine rich repeat kinase 2 (LRRK2) and PDZ domain containing ring finger 4 (PDZRN4) were identified in the 2.27 Mb region on SSC5. In conclusion, our results may provide a set of markers useful for genetic improvement of IFC in pigs and will advance the genome selection process of IFC on pig breeding programmes.

Uptake of evidence by physicians: De-adoption of erythropoiesis-stimulating agents after the TREAT trial

Background

Variation in de-adoption of ineffective or unsafe treatments is not well-understood. We examined de-adoption of erythropoiesis-stimulating agents (ESA) in anemia treatment among patients with chronic kidney disease (CKD) following new clinical evidence of harm and ineffectiveness (the TREAT trial) and the FDA’s revision of its safety warning.

Method

We used a segmented regression approach to estimate changes in use of epoetin alfa (EPO) and darbepoetin alfa (DPO) in the commercial, Medicare Advantage (MA) and Medicare fee-for-service (FFS) populations. We also examined how changes in both trends and levels of use were associated with physicians’ characteristics.

Results

Use of DPO and EPO declined over the study period. There were no consistent changes in DPO trend across insurance groups, but the level of DPO use decreased right after the FDA revision in all groups. The decline in EPO use trend was faster after the TREAT trial for all groups. Nephrologists were largely more responsive to evidence than primary care physicians. Differences by physician’s gender, and age were not consistent across insurance populations and types of ESA.

Conclusions

Physician specialty has a dominant role in prescribing decision, and that specializations with higher use of treatment (nephrologists) were more responsive to new evidence of unsafety and ineffectiveness.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02491-y.

[Repair methods and clinical effects of full-thickness burn wounds deep to tendon or even bone in fingers]

Objective: To explore the repair methods and clinical effects of full-thickness burn wounds deep to tendon or even bone in fingers. Methods: A retrospective non-randomized controlled trial was conducted on the 98 patients with full-thickness finger burns deep to tendon or even bone who met the inclusion criteria and were hospitalized in Xiangya Hospital of Central South University from January 2010 to December 2019. Among the 98 patients, there were 81 males and 17 females, aged from 1 to 72 years, with 160 fingers involved. The wound area of each of affected fingers ranged from 2.0 cm×1.5 cm to 12.0 cm×3.5 cm, and the maximum wound area after merging the affected fingers was 12.0 cm×10.0 cm. For adult hands with multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers or children with full-thickness finger burns deep to tendon or even bone, pedicled abdominal flaps were selected. For adults with single or two fingers with full-thickness burns deep to tendon or even bone, the pedicled internal hand flaps and free tissue flaps were selected. The free tissue flap repair requires good vascular conditions in the recipient area with arteries and veins available for anastomosis. For thumb nail burns deep to tendon or even bone or partial absence of the thumb after burns, the thumbs were reconstructed with the first toenail flap or dorsal foot flap with the second toe. In this study, 45 pedicled abdominal flaps were used to repair the wounds in 91 fingers, 37 pedicled internal hand flaps were used to repair the wounds in 37 fingers, 26 free tissue flaps were used to repair the wounds in 28 fingers, 3 first toenail flaps were used to reconstruct 3 patients' thumb nails and to repair hand wounds, and 1 dorsal foot flap with the second toe was used to reconstruct 1 patient's thumb and to repair hand and wrist wounds. The tissue flap area was from 2.0 cm×1.5 cm to 20.0 cm×10.0 cm. The wound in the donor site was repaired by direct suture or full-thickness skin grafting from the medial upper arm of the affected limb or split-thickness skin grafting from the outer thigh. The postoperative survival of the tissue flap, postoperative complications, and appearance and function of the flap donor site were observed. For the patients who were followed up, their finger functions were evaluated at the last follow-up using the trial criteria for replantation function evaluation of the amputated finger issued by the Hand Surgery Society of the Chinese Medical Association, and the satisfaction of the patients was investigated using the Efficacy Satisfaction Scale. Data were statistically analyzed with Kruskal-Wallis H test and Nemenyi test. Results: Of the 112 tissue flaps, 104 tissue flaps survived completely and had good blood circulation; 1 pedicled thumb dorsal ulnar reverse island flap, 1 pedicled finger artery cutaneous branch reverse island flap, and 1 free grafted anterolateral thigh perforator flap were slightly necrotic at the end, which were repaired with outer thigh split-thickness skin graft after dressing change and granulation tissue growth; 2 free grafted tarsal external artery flaps and 1 pedicled thumb dorsal ulnar reverse island flap suffered from postoperative venous return obstruction, which survived after partial suture removal and heparin saline cleansing of the wound; 1 pedicled modified dorsal metacarpal artery retrograde island flap and 1 free grafted peroneal artery perforator flap were necrotic, which were repaired by a pedicled abdominal flap and a lateral upper arm flap free transplantation respectively in stage Ⅱ. After transplantation, the tissue flaps had good shape, soft texture, and good elasticity, without bloating. There was no functional disorder in the flap donor site, and only slight scar remained. A total of 117 fingers of the 72 patients received 3-24 months of outpatient or telephone follow-up. At the last follow-up, the excellent and good rates of function evaluation of fingers repaired with pedicled abdominal flap, pedicled internal hand flap, and free tissue flap were respectively 77.3% (51/66), 96.3% (26/27), and 95.8% (23/24). The function of fingers repaired with free tissue flap and pedicled internal hand flap was significantly better than that with pedicled abdominal flap (P<0.01). The satisfaction of patients with fingers repaired by free tissue flaps was significantly higher than that by pedicled abdominal flap (P<0.05). Conclusions: According to the specific situation of full-thickness burn wounds deep to tendon or even bone in fingers, the pedicled abdominal flap is used to repair the multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers of adult or the full-thickness burn wounds deep to tendon or even bone in fingers of children, the pedicled internal hand flap or free tissue flap is used to repair the full-thickness burn wounds deep to tendon or even bone in single or two fingers of adult patients, and the first toenail flap or the dorsal foot flap with the second toe is used to reconstruct the thumbs with full-thickness burn deep to tendon or even bone, with high postoperative tissue flap survival rate and few complications. The functional recovery of the affected finger is better after repair with free tissue flap and pedicled internal hand flap, and the patients' satisfaction is the highest after free tissue flap repair.

[Mesenchymal stem cells derived apoptotic extracellular vesicles attenuate pro-inflammatory macrophages induced by Porphyromonas gingivalis lipopolysaccharide]

Objective: To investigate whether bone marrow mesenchymal stem cells (BMMSCs) derived apoptotic extracellular vesicles (ApoEVs) could regulate the polarization of mouse macrophage cell line RAW264.7 and whether BMMSCs derived ApoEVs could attenuate pro-inflammatory condition of RAW264.7 induced by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS), so as to provide experimental evidence and theoretical basis for using BMMSCs derived ApoEVs as a method to treat periodontitis. Methods: The Operetta CLS high-content analysis system was used to observe the time-dependent apoptosis process of BMMSCs. Besides, field emission scanning electron microscopy (FESEM), dynamic light scattering technology and streaming potential method were used to measure the surface characteristics of BMMSCs derived ApoEVs. The Operetta CLS high-content analysis system was used to observe the process of RAW264.7 phagocyting 5-carboxy-tetramethylrhodamine, succinimidyl ester (5-TAMRA-SE) labeled ApoEVs. Real-time quantitative PCR was used to detect the mRNA expression of arginase-1 (Arg-1). Cell immunofluorescence and Western blotting were used to detect the number of inducible nitric oxide synthase (iNOS)(+) macrophages and iNOS protein expression level in each experiment group. Enzyme linked immunosorbent assay was used to detect tumor necrosis factro-α (TNF-α) level in the Pg-LPS induced pro-inflammatory macrophage culture supernatant in each experiment group. Results: After treating with 0.5 μmol/L staurosporine for 12 hours, mouse BMMSCs underwent shrinking with obvious vesicles structure around. The FESEM showed the ApoEVs were in spherical shapes. The size range of ApoEVs was about 100-1 000 nm and the average Zeta potential was -16.6 mV. The Operetta CLS high-content analysis system showed RAW264.7 could phagocytose 5-TAMRA-SE labeled ApoEVs by pseudopodia. The relative mRNA expression of Arg-1 was significantly increased in RAW 264.7 after being treated with interleukin 4 (IL-4) and ApoEVs (261.97±15.91) compared to that with IL-4 alone (115.29±15.42) (P<0.01). Cell immunofluorescence showed that ApoEVs could reduce the number of iNOS(+) macrophages induced by Pg-LPS (39.33±4.70) comparing to those without ApoEVs (95.33±4.70) (P=0.007). In the meanwhile, ApoEVs could also down-regulate the iNOS protein level of macrophages induced by Pg-LPS (5.84±1.05) comparing to those without ApoEVs (14.91±3.87) (P<0.01). Besides, ApoEVs could also reduce the TNF-α secretion in the culture supernatant of pro-inflammatory macrophages induced by Pg-LPS [(21 899.71±409.73) ng/L] comparing to those without ApoEVs [(71 296.50±2 344.22) ng/L] (P=0.003). Conclusions: BMMSCs derived ApoEVs could regulate the polarization of macrophages and could also attenuate the pro-inflammatory condition of macrophages induced by Pg-LPS.

Application of Monte Carlo Algorithms to Cardiac Imaging Reconstruction

Monte Carlo algorithms have a growing impact on nuclear medicine reconstruction processes. One of the main limitations of myocardial perfusion imaging (MPI) is the effective mitigation of the scattering component, which is particularly challenging in Single Photon Emission Computed Tomography (SPECT). In SPECT, no timing information can be retrieved to locate the primary source photons. Monte Carlo methods allow an event-by-event simulation of the scattering kinematics, which can be incorporated into a model of the imaging system response. This approach was adopted in the late Nineties by several authors, and recently took advantage of the increased computational power made available by high-performance CPUs and GPUs. These recent developments enable a fast image reconstruction with improved image quality, compared to deterministic approaches. Deterministic approaches are based on energy-windowing of the detector response, and on the cumulative estimate and subtraction of the scattering component. In this paper, we review the main strategies and algorithms to correct the scattering effect in SPECT and focus on Monte Carlo developments, which nowadays allow the threedimensional reconstruction of SPECT cardiac images in a few seconds.

Hypoxia-mediated down-regulation of miRNAs' biogenesis promotes tumor immune escape in bladder cancer

BACKGROUND

The study examines the function of hypoxia-mediated down-regulation of microRNAs (miRNAs) (mir-30c, mir-135a, and mir-27a) in the process of bladder cancer immune escape.

METHODS

Quantitative Real-time PCR (qRT-PCR) was carried out to determine gene expression levels of Drosha and Dicer under hypoxia treatment, while western blotting and flow cytometry were used to determine protein expression. Seven reported miRNAs were identified via qRT-PCR assay. Flow cytometry detection of CD3/CD4/CD8-positive expression and statistics. Enzyme-linked immunosorbent assay (ELISA) detected cellular immune factors content. Cell apoptosis was checked via flow cytometry assay. Luciferase report assay and western blot assays were both used to verify the relationship between miRNAs and Casitas B-lineage lymphoma proto-oncogene b (Cbl-b). The animal model was established and Hematoxylin-eosin (HE) staining, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, and immunohistochemistry (IHC) assays were separately used to verify the conclusions.

RESULTS

The CD3 + /CD4 + expression was increased in the hypoxia group, while CD3 + /CD8 + expression, the cellular immune factors content Interleukin-2 (IL-2) and Tumor Necrosis Factor-α (TNFα) along with the cell apoptosis were suppressed. The protein expression of Cbl-b was found to be up-regulated in the hypoxia group. After constructing the overexpression/ knockdown of Cbl-b in peripheral blood mononuclear cell (PBMC), Cbl-b has been found to promote tumor immune escape in bladder cancer. Furthermore, Cbl-b had been identified as the co-targets of mir-30c, mir-135a, and mir-27a and down-regulation of miRNA biogenesis promotes Cbl-b expression and deactivating T cells in vitro/in vivo.

CONCLUSION

Hypoxia-mediated down-regulation of miRNAs' biogenesis promotes tumor immune escape in bladder cancer, which could bring much more advance to the medical research on tumors.

Determinants of self-management behaviors among pulmonary tuberculosis patients: a path analysis

Background

Tuberculosis (TB) is one of the top 10 causes of death in the world. Since Directly Observed Therapy (DOT) as a core strategy for the global TB control are not applicable to all types of TB patients, and self-management of TB patients (SMTP) as a patient-centered supervision type is a supplement to DOT and can improve TB case management. However, the factors related to SMTP are complex and need more study. This study aimed at identifying the determinants of SMTP and examining the direct/indirect effects of these determinants.

Methods

The purposive sampling technique was used to select study sites and participants were recruited from the study sites by the consecutive sampling method. The PRECEDE model was used as the framework to analyze the determinants of SMTP. The responses of TB patients were acquired via a questionnaire survey for data collection. A Pearson correlation analysis was used to define the relationship between the predisposing, enabling, reinforcing factors with SMTP behaviors. A regression-based path analysis was used to determine the action paths of the predisposing, enabling, and reinforcing factors on SMTP behaviors.

Results

The predisposing (TB knowledge), enabling [health education and healthcare workers (HCWs) support], reinforcing factors (family support) had significant positive correlations with SMTP behaviors (P < 0.05). The predisposing, enabling, reinforcing factors were positively correlated with each other (r = 0.123‒0.918, P < 0.05), except for family support and HCWs support. The predisposing factors (TB knowledge, β = 0.330) and the enabling factors (HCWs support, β = 0.437) had direct effects on SMTP behaviors. The enabling factors (health education and HCWs support) and the reinforcing factors (family support) had indirect effects on SMTP behaviors.

Conclusions

This study revealed the effects and action path of TB knowledge, health education, HCWs support, and family support on SMTP behaviors via a path analysis. Assessing patient’s needs for SMTP along with promoting effective TB health education and providing firm support from HCWs and family members are potential strategies to promote SMTP behaviors.

Graphic abstract

[SHOX2 promotes migration, invasion and stemness of bladder cancer cells in vitro]

OBJECTIVE

To explore the role of human short stature homeobox 2 (SHOX2) in regulating the migration, invasion and stemness of human bladder cancer cells.

METHODS

We analyzed SHOX2 gene expression in bladder cancer and adjacent tissues based on TCGA database. Univariate survival analysis of SHOX2 gene expression in TCGA-BLCA data was performed using GEPIA. The probable function of SHOX2 was predicted using GSEA. Human bladder cancer T24 cell models of SHOX2 knockdown or overexpression were assessed for changes in migration and invasion abilities using wound healing assay and Transwell assay, and their cancer stem cell-like characteristics were evaluated using tumorsphere formation assay and colony formation assay. Western blotting was used to detect the expressions of epithelial mesenchymal transition (EMT) markers Ecadherin and vimentin and the TGF-β signaling network component TβR-I in the cells.

RESULTS

SHOX2 expression was significantly higher in bladder cancer tissues than in the adjacent tissues (P < 0.05), especially in paired tissue specimens (P < 0.01), and was negatively correlated with the overall survival of the patients (P < 0.05). SHOX2 gene expression was correlated positively with EMT-related (P < 0.05) and stemness-related gene signatures (P < 0.01). In T24 cells, SHOX2 knockdown significantly suppressed cell migration and invasion, which was significantly enhanced by SHOX2 overexpression (P < 0.01). The cancer stem cell-like characteristics of T24 cells was repressed by SHOX2 knockdown but significantly enhanced by SHOX2 overexpression (P < 0.01). SHOX2 knockdown induced morphological changes of the cells into epithelioid cells, whereas SHOX2 overexpression induced a mesenchymal morphology of the cells. SHOX2 knockdown increased E-cadherin expression and decreased vimentin and TβR-I expression, while SHOX2 overexpression increased the expressions of vimentin and TβR-I in the cells.

CONCLUSION

SHOX2 promotes the migration, invasion and stemness of human bladder cancer cells possibly by regulating EMT via the TGF-β signaling pathway.

[The prognostic factors of extramedullary relapse after allogeneic hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia]

To analyze the prognostic factors of extramedullary relapse (EMR) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute lymphoblastic leukemia (ALL).The clinical data of 33 relapsed patients in 95 ALL patients receiving allo-HSCT were analyzed retrospectively. The median time of relapse was 5.7 (0.7-52.3) months. Extramedullary relapse was recorded in 10 cases (10.5%), bone marrow relapse in 15 cases (15.8%), and both extramedullary and marrow relapse were seen in 8 cases (8.4%). The median time of EMR was 7.4(0.7-52.3) months. The most commonly involved organ was central nervous system, followed by testis and bone. The 3-year OS rate in EMR patients was (33.3±11.1) %. Univariate analysis showed that disease state before transplantation (P=0.026), extramedullary infiltration before transplantation (P=0.005), conditioning regimens (P=0.033) and acute graft-versus-host disease(aGVHD) (P=0.013) were significantly correlated with EMR. Multivariate analysis suggested that extramedullary infiltration (RR=5.067, 95%CI1.542-16.645, P=0.007) and aGVHD(RR=3.585, 95%CI1.245-10.320, P=0.018) were independent predictive factors of EMR in ALL patients after allo-HSCT.

Genetically predicted circulating levels of copper and zinc are associated with osteoarthritis but not with rheumatoid arthritis

OBJECTIVE

Osteoarthritis (OA) and rheumatoid arthritis (RA) are both debilitating diseases that cause significant morbidity and disability globally. This study aims to investigate the causal effects of varying blood levels of five minerals -- iron, zinc, copper, calcium, and magnesium, on OA and RA.

DESIGN

We performed two-sample Mendelian randomization (MR) analyses to assess the associations of five circulating minerals with OA and RA. Single nucleotide polymorphisms (SNPs) serving as genetic instruments for the circulating mineral levels were selected from large genome-wide association studies of European-descent individuals. The associations of these SNPs with OA and RA were evaluated in UK Biobank participants. Multiple sensitivity analyses were applied to detect and correct for the presence of pleiotropy.

RESULTS

Genetically determined copper and zinc status were associated with OA, but not with RA. Per standard deviation (SD) increment in copper increases the risk of OA (OR = 1.07, 95% CI: 1.02-1.13) and one of its subtypes, localized OA (OR = 1.08, 95% CI: 1.03-1.15). Per SD increment in zinc is positively associated with risks of OA (OR = 1.07, 95% CI: 1.01-1.13), generalized OA (OR = 1.18, 95% CI: 1.05-1.31), and unspecified OA (OR = 1.21, 95% CI: 1.11-1.31). Additionally, per SD increment in calcium decreases the risk of localized OA (OR = 0.83, 95% CI: 0.69-0.98).

CONCLUSIONS

Genetically high zinc and copper status were positively associated with OA, but not with RA. Given the modifiable nature of circulating mineral status, these findings warrant further investigation for OA prevention strategies.

[Efficacy and safety of anti-PD-1 monoclonal antibody in advanced hepatocellular carcinoma after TACE combined with TKI therapy]

Objective: To evaluate the efficacy and safety of anti-programmed cell death 1 (PD-1) receptor monoclonal antibody (MoAb) in patients with advanced hepatocellular carcinoma (HCC) after treatment of transcatheter arterial chemoembolization (TACE) combined with tyrosine kinase inhibitor (TKI). Methods: From February 2019 to February 2020, 56 HCC patients who relapsed after TACE-TKI treatment in Department of Interventional Radiology, The Second Affiliated Hospital of Guangzhou Medical University were enrolled. All patients received anti-PD-1 MoAb (sintilimab injection) and followed up every 6 weeks. According to mRECIST, the curative effect was evaluated as complete response (CR), partial response (PR), stable disease (SD) or progressive disease (PD). Objective response rate (ORR) and disease control rate (DCR), progression-free survival (PFS) and treatment-related adverse events (TRAEs) were recorded. Univariate analysis by Chi-square test and binary logistic regression model was used to determine the influencing factors of DCR. The Kaplan-Meier method and Cox proportional hazard regression model were used to analyze the survival data. Results: A total of 48 patients were enrolled in this study including 42 males and 6 females, with a median age of 55 years (29-71 years). ECOG scores comprised of 0 in 24 cases, 1-2 in 24 cases. Thirty-six patients were in Child-Pugh grade A of liver function and 12 cases were grade B. The median follow-up time was 4.5 months. There were 2 patients achieved CR, 12 patients with PR and 16 with SD. ORR was 29.2%, DCR was 62.5%. The independent influencing factors of DCR was ECOG score and AFP level (P=0.031, P=0.012). Median PFS was 4.1 months (95%CI 2.7-5.4 months), and ECOG score was the independent influencing factor of PFS (P=0.042). Treatment-related adverse events were reported in 70.8% (34/48) patients. Incidence of grade Ⅲ-Ⅳ TRAEs was 22.9% (11/48). Conclusion: In patients with HCC who relapse from TACE and TKI treatment, anti-PD-1 monoclonal antibody is efficacious safe especially in those with ECOG 0 score.

Myriocin alleviates Oleic/Palmitate induced chondrocyte degeneration via the suppression of ceramide

OBJECTIVE

Abnormal lipid metabolism plays a role that cannot be ignored in articular cartilage bone marrow lesions, synovial inflammation, and the destruction of chondrocytes (CHs). Ceramide is one of the key constructions of membrane lipid bilayers, which is an intracellular lipid mediator regulating varieties of cellular behaviors. The purpose of this study was to explore the role of ceramide and its inhibitor in the development of the CHs degeneration.

PATIENTS AND METHODS

CHs were isolated from the cartilage collecting from the osteoarthritis (OA) patients, and oleic acid/palmitic (O/P) acid was used to induce CHs lipid disordered. Then, myriocin was used to inhibit the accumulation of ceramide. After that, the apoptosis, cell viability, glucose uptake, oxidative stress, and the chondrogenic gene expression were tested to evaluate the degenerated degree of CHs.

RESULTS

Results revealed that O/P induced CH apoptosis, ceramide accumulation, a higher level of oxidative stress, IL-1β and MMP-13, but it also decreased the collagen-Ⅱ and SOX-9 expressions and affected the glucose uptake of CHs. After the stimulation of myriocin, the side effects induced by O/P was partly reversed.

CONCLUSIONS

O/P induces the accumulation of ceramide and the degeneration of CHs, and myriocin can reject the harmful effect caused by O/P via the suppression of ceramide.

Effectiveness of XP-Endo Finisher and passive ultrasonic irrigation on intracanal medicament removal from root canals: a systematic review and meta-analysis

Background

XP-Endo Finisher (XPF) and passive ultrasonic irrigation (PUI) are commonly used in intracanal medicament removal. The effectiveness of these two techniques needs to be compared, and evidence-based research should be conducted.

Methods

A comprehensive literature search was conducted in PubMed, Web of Science, Embase, Cochrane Library, and Google Scholar up to December 20th, 2020. The outcomes of the included trials were pooled into the Cochrane Collaboration’s Review Manager 5.3 software. Cochrane’s risk-of-bias tool 2.0 was applied to assess the risk of bias.

Results

Nine articles were included in this systematic review and processed for data extraction, and eight studies were identified for meta-analysis. In general, the use of PUI showed better medicament removal effectiveness than XPF (odds ratio [OR]: 3.09; 95% confidence interval [CI], 1.96–4.86; P < 0.001). PUI was also significantly more efficient than XPF in the apical third (OR: 3.42; 95% CI, 1.32–8.84; P = 0.01). For trials using sodium hypochlorite (NaOCl) alone, PUI was also significantly more effective than XPF on intracanal medicaments removal (OR: 5.23; 95% CI, 2.79–9.82; P < 0.001). However, there was no significant difference between PUI and XPF when NaOCl and ethylenediaminetetraacetic acid (EDTA) were used in combination (OR: 1.51; 95% CI, 0.74–3.09; P = 0.26). In addition, for studies whose intracanal medicament periods were two weeks, the effectiveness of PUI was statistically better than the XPF (OR: 7.73; 95% CI, 3.71–16.07; P < 0.001). Nevertheless, for trials whose intracanal medicament time was one week or over two weeks, no differences between the XPF and PUI were found (OR: 1.54; 95% CI, 0.74–3.22; P = 0.25) (OR: 1.42; 95% CI, 0.44–4.61; P = 0.56).

Conclusions

The meta-analysis is the first study to quantitatively compare the effectiveness of XPF and PUI techniques on intracanal medicaments removal. With rigorous eligibility criteria, the study only included high-quality randomised controlled trials. The study indicated that PUI might be superior over XPF techniques for removing intracanal medicaments from artificial standardized grooves and cavities in the root canal system. The anatomical areas, irrigation protocol, and intracanal medicaments time may influence the cleaning efficacy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01644-7.

Inhibitory effects of quercetin and its major metabolite quercetin-3-O-β-D-glucoside on human UDP-glucuronosyltransferase 1A isoforms by liquid chromatography-tandem mass spectrometry

Quercetin is a flavonoid that is widely present in plant-derived food. Quercetin-3-O-β-D-glucoside (Q3GA) is a predominant metabolite of quercetin in animal and human plasma. The inhibitory effects of the UDP-glucuronosyl transferases (UGTs) caused by herbal components may be a key factor for the clinical assessment of herb-drug interactions (HDIs). The present study aimed to investigate the inhibitory profile of quercetin and Q3GA on recombinant UGT1A isoforms in vitro. The metabolism of the nonspecific substrate 4-methylumbelliferone (4-MU) by the UGT1A isoforms was assessed by liquid chromatography-tandem mass spectrometry. Preliminary screening experiments indicated that quercetin exhibited stronger inhibitory effects on UGT1A1, UGT1A3, UGT1A6 and UGT1A9 enzymes than Q3GA. Kinetic experiments were performed to characterize the type of inhibition caused by quercetin and Q3GA towards these UGT isoforms. Quercetin exerted non-competitive inhibition on UGT1A1 and UGT1A6, with half maximal inhibitory concentration (IC₅₀) values of 7.47 and 7.07 µM and inhibition kinetic parameter (K_i) values of 2.18 and 28.87 µM, respectively. Quercetin also exhibited competitive inhibition on UGT1A3 and UGT1A9, with IC₅₀ values of 10.58 and 2.81 µM and K_i values of 1.60 and 0.51 µM, respectively. However, Q3GA displayed weak inhibition on UGT1A1, UGT1A3 and UGT1A6 enzymes with IC₅₀ values of 45.21, 106.5 and 51.37 µM, respectively. In the present study, quercetin was a moderate inhibitor of UGT1A1 and UGT1A3, a weak inhibitor of UGT1A6, and a strong inhibitor on UGT1A9. The results of the present study suggested potential HDIs that may occur following quercetin co-administration with drugs that are mainly metabolized by UGT1A1, UGT1A3 and UGT1A9 enzymes.

Brugada syndrome in Hong Kong: long term outcome prediction through machine learning

Funding Acknowledgements

Type of funding sources: None.

Introduction

 Brugada syndrome (BrS) is an ion channelopathy that predisposes affected patients to spontaneous ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death (SCD). Despite its greater prevalence in Asia and epidemiological heterogeneity in disease manifestation, the majority of the conducted cohort studies available in current literature are based in Western countries. 

Purpose

The aim of this study is to examine the clinical and electrocardiographic predictive factors of spontaneous VT/VF for Asian BrS patients.

Methods

This was a territory-wide retrospective cohort study of patients diagnosed with BrS between 1997 and 2019. The primary outcome was spontaneous VT/VF detected either during hospital admission or by implantable-cardioverter defibrillator (ICD) data. Cox regression was used to identify significant clinical and electrocardiographic risk predictors. Non-linear interactions between variables (latent patterns) were extracted using non-negative matrix factorization (NMF) and used as inputs into the random survival forest (RSF) model.

Results

This study included 516 consecutive BrS patients (mean age of initial presentation= 50 ± 16 years, male= 92%) with a median follow-up of 86 (interquartile range: 45-118) months. The cohort was divided into subgroups based on initial disease manifestation: asymptomatic (n = 314), syncope (n = 159) or VT/VF (n = 41). Annualized event rates per person-year were 1.70%, 0.05% and 0.01% for the VT/VF, syncope and asymptomatic subgroups, respectively. Multivariate Cox regression analysis revealed initial presentation of VT/VF (HR = 24.0, 95% CI = [1.21, 479] , P= 0.037) and standard deviation of P-wave duration (HR = 1.07, 95% CI = [1.00, 1.13], P = 0.044) were significant predictors. The NMF-RSF showed the best predictive performance compared to RSF and Cox regression models (precision: 0.87 v.s. 0.83 v.s. 0.76, recall: 0.89 v.s. 0.85 v.s. 0.73, F1-score: 0.88 v.s. 0.84 v.s. 0.74).

Conclusions

This is one of the largest territory-wide cohort studies on BrS and the largest study in Asia published to date, with an extensive median follow-up duration of 7 years. Clinical history, electrocardiographic markers and investigation results provide important information for risk stratification. Machine learning techniques using NMF and RSF significantly improves overall risk stratification performance.

Identification of candidate genes associated with slaughter traits in F2 chicken population using genome-wide association study

Slaughter traits are crucial economic traits of chickens. We performed a GWAS to discover critical loci and candidate genes for 21 slaughter traits in an F2 chicken population resulting from crossing Luxi gamecocks and recessive white feather broilers. We found some SNPs and genes which were significantly associated with keel length, head length, body slope length, bilateral leg weight without shin, bilateral foot weight, subcutaneous fat thickness, heart weight, muscular stomach weight and glandular stomach weight. This study provides references for further investigation of slaughter traits and molecular breeding in chicken.