Tracing Photoinduced Hydrogen Migration in Alcohol Dications from Time-Resolved Molecular-Frame Photoelectron Angular Distributions

The recent implementation of attosecond and few-femtosecond X-ray pump/X-ray probe schemes in large-scale free-electron laser facilities has opened the way to visualize fast nuclear dynamics in molecules with unprecedented temporal and spatial resolution. Here, we present the results of theoretical calculations showing how polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) can be used to visualize the dynamics of hydrogen migration in methanol, ethanol, propanol, and isopropyl alcohol dications generated by X-ray irradiation of the corresponding neutral species. We show that changes in the PA-MFPADs with the pump-probe delay as a result of intramolecular photoelectron diffraction carry information on the dynamics of hydrogen migration in real space. Although visualization of this dynamics is more straightforward in the smaller systems, methanol and ethanol, one can still recognize the signature of that motion in propanol and isopropyl alcohol and assign a tentative path to it. A possible pathway for a corresponding experiment requires an angularly resolved detection of photoelectrons in coincidence with molecular fragment ions used to define a molecular frame of reference. Such studies have become, in principle, possible since the first XFELs with sufficiently high repetition rates have emerged. To further support our findings, we provide experimental evidence of H migration in ethanol-OD from ion-ion coincidence measurements performed with synchrotron radiation.

[Diagnosis and treatment understanding of Waldenström macroglobulinemia in China: a cross-sectional study]

Objective: To conduct a nationwide physician survey to better understand clinicians' disease awareness, treatment patterns, and experience of Waldenström macroglobulinemia (WM) in China. Methods: This cross-sectional study was conducted from February 2022 to July 2022 by recruiting clinicians with WM treatment experience from hematology, hematology-oncology, and oncology departments throughout China. Quantitative surveys were designed based on the qualitative interviews. Results: The study included 415 clinicians from 219 hospitals spread across thirty-three cities and twenty-two provinces. As for diagnosis, the laboratory tests prescribed by physicians for suspected WM patients were relatively consistent (92% -99% recommendation for laboratory, 79% -95% recommendation for pathology, 96% recommendation for gene testing, and 63% -83% recommendation for imaging examination). However, from a physician's perspective, there was 22% misdiagnosis occurred in clinical practice. The rate of misdiagnosis was higher in lower-level hospitals than in tertiary grade A hospitals (29% vs 21%, P<0.001). The main reasons for misdiagnosis were that WM was easily confused with other diseases, and physicians lacked the necessary knowledge to make an accurate diagnosis. In terms of gene testing in clinical practice, 96% of participating physicians believed that WM patients would require gene testing for MYD88 and CXCR4 mutations because the results of gene testing would aid in confirming diagnosis and treatment options. In terms of treatment, 55% of physicians thought that the most important goal was to achieve remission, while 54% and 51% of physicians wanted to improve laboratory and/or examination results and extend overall survival time, respectively. Among patients with treatment indications, physicians estimated that approximately 21% of them refused to receive treatment, mainly owing to a lack of affordable care and disease awareness. When selecting the most appropriate treatment regimens, physicians would consider patient affordability (63% ), comorbidity (61% ), and risk level (54% ). Regimens containing Bruton tyrosine kinase inhibitor (BTKi) were most widely recommended for both treatment-naïve and relapsed/refractory patients (94% for all patients, 95% for treatment-naïve patients, and 75% for relapsed/refractory patients), and most physicians recommended Ibrutinib (84% ). For those patients who received treatment, physicians reported that approximately 23% of patients did not comply with the treatment regimen due to a lack of affordability and disease awareness. Furthermore, 66% of physicians believe that in the future, increasing disease awareness and improving diagnosis rates is critical. Conclusions: This study is the first national physician survey of WM conducted in China. It systematically describes the issues that exist in WM diagnosis and treatment in China, such as a high rate of misdiagnosis, limited access to gene testing and new drugs, and poor patient adherence to treatment. Chinese doctors believe that improving doctors' and patients' understanding of WM is one of the most urgent issues that must be addressed right now.

Notch signaling regulates Th17 cells differentiation through PI3K/AKT/mTORC1 pathway and involves in the thyroid injury of autoimmune thyroiditis

PURPOSE

Autoimmune Thyroiditis (AIT) is the most common thyroid disease; however, there were no measures to prevent the progression of the disease. The present study attempts to identify that Notch signaling regulates the differentiation of T helper 17 (Th17) cells by activating downstream Phosphatidylinositol-3 kinase/protein kinase/mechanistic target of rapamycin complex 1 (PI3K/AKT/mTORC1) pathway participating in the thyroid injury of the experimental autoimmune thyroiditis (EAT).

METHODS

In vivo experiments, mice were randomly divided into 4 groups: a control group, an EAT group, and two groups with LY294002 treatment (pTg plus 25 mg/kg or 50 mg/kg LY294002, respectively). The degrees of thyroiditis were evaluated, and the percentage of Th17 cells, expression of interleukin-17A (IL-17A), and the main components of the Notch-PI3K signaling pathway were detected in different groups. In vitro experiments, two different dosages of LY294002 (25 and 50 μM) were used to intervene splenic mononuclear cells (SMCs) from EAT mice to further evaluate the regulatory effect of Notch-PI3K pathway on Th17 cells.

RESULTS

Our data demonstrate that the infiltration of Th17 cells and the expressions of IL-17A, Notch, hairy and split 1 (Hes1), p‑AKT (Ser473), p‑AKT (Thr308), p‑mTOR (Ser2448), S6K1, and S6K2 increased remarkably in EAT mice. After PI3K pathway was blocked, the degrees of thyroiditis were significantly alleviated, and the proportion of Th17 cells, the expression of IL-17A, and the above Notch-PI3K pathway-related molecules decreased in a dose-dependent manner. Additionally, the proportion of Th17 cells was positively correlated with the concentration of serum thyroglobulin antibody (TgAb), IL-17A, and Notch-PI3K pathway-related molecules mRNA levels.

CONCLUSIONS

Notch signal promotes the secretion of IL-17A from Th17 cells by regulating the downstream PI3K/AKT/mTORC1 pathway through Hes-Phosphatase and tensin homolog (PTEN) and participates in thyroid autoimmune damage, and the PI3K pathway inhibitor may play important effects on AIT by affecting Th17 cells differentiation.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

[Status and associated factors of pre-exposure prophylaxis use among men who have sex with men in 24 cities in China]

Objective: To understand the cognition and medication use of pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) in China and its associated factors. Method: From August 25 to September 5, 2021, 2 447 MSM were recruited in 24 cities to complete the online questionnaire through a male social interaction platform, Blued 7.5 software. The survey contents included demographic information of the respondents, PrEP awareness and usage, and risk behaviors. Descriptive analysis and multi-level logistic regression were performed for data analysis. SPSS 24.0 and SAS 9.4 software were used for statistical analysis. Results: Among the 2 447 respondents of MSM, 1 712 (69.96%) had heard of PrEP, 437 (17.86%) ever used PrEP, 274 (11.20%) were on PrEP, and 163 (6.66%) had discontinued PrEP; among the 437 cases (whoever used PrEP), more than 61.88% (388/627) adopted emtricitabine/tenofovir disoproxil fumarate regimen, and most of them adopted on-demand regimen. The average PrEP dosage reported in the past year is 1.12 tabletsper person per week. PrEP purchase was primarily via an online channel, and the most concerned factor was the PrEP effectiveness on HIV prevention. The most common reasons for discontinuing PrEP, reported by 163 cases, were the lack of HIV risk perception, the use of a condom to prevent HIV, and the economic burden of PrEP use. The logistic regression analysis showed that PrEP use among MSM in 24 cities was statistically associated with age, monthly income, ever having unprotected anal sex in the past year, used sexual drugs and sexually transmitted disease (STD) diagnosis in the past year. Compared with MSM aged 18-24, the proportion of MSM was relatively lower among those aged 25-44, who discontinued the PrEP (aOR=0.54,95%CI:0.34-0.87) or never used PrEP (aOR=0.62,95%CI:0.44-0.87). The proportion of unprotected anal sex among MSM currently on PrEP use was higher than those who have stopped PrEP and never used PrEP (all P<0.05). Those MSM group, with monthly income higher than 5 000 Yuan, used sexual drugs and STD diagnosis in the past year were more likely to have a higher rate for PrEP usage (all P<0.05). Conclusions: Currently, pre-exposure prophylaxis in the MSM group is primarily obtained via the online channel and adopted in an on-demand mode. Although the PrEP users have reached a certain proportion, it is still necessary to strengthen health education on the PrEP effects and side effects of MSM and to improve the awareness and use rate, especially for young MSM group, which can be combined with the advantages of the internet targeting its needs and use barriers.

Phyllosticta rizhaoensis sp. nov. causing leaf blight of Ophiopogon japonicus in China

Ophiopogon japonicus (Asparagaceae) is a perennial grass species which can be cultivated as an ornamental and medicinal plant. From April 2021 to September 2022, a serious leaf blight disease of O. japonicus was discovered in Rizhao City, Shandong Province, China. The initial disease symptoms were small yellow spots, finally developing as tip blight, often associated with many small, black, semi-immersed pycnidial conidiomata formed in lesions. To obtain isolates of the causal agent for this disease, samples were randomly collected from O. japonicus diseased leaves in Rizhao City. In total 97 Phyllosticta isolates were obtained from samples, and studied using morphological features and multi-locus phylogenetic analyses of a combined dataset using the internal transcribed spacers (ITS), the 28S large subunit of ribosomal RNA (LSU), and partial translation elongation factor 1-alpha (tef), actin (act) and glyceraldehyde-3-phosphate dehydrogenase (gapdh) loci. Phylogenetically, these Phyllosticta isolates formed a clade in the P. concentrica species complex, and clustered with P. pilospora and P. spinarum. Morphologically, isolates in this clade differed from P. pilospora and P. spinarum by the size of conidiogenous cells and conidia, and the absence of an apical conidial appendage. As a result, these isolates were described as a novel species Phyllosticta rizhaoensis. Pathogenicity was confirmed using Koch's postulates, which showed that P. rizhaoensis could induce leaf blight symptoms on O. japonicus in China. Citation: Wang C-B, Wang T-T, Ma C-Y, Xue H, Li Y, Piao C-G, Jiang N (2023). Phyllosticta rizhaoensis sp. nov. causing leaf blight of Ophiopogon japonicus in China. Fungal Systematics and Evolution 11: 43-50. doi: 10.3114/fuse.2023.11.03.

[Analysis of on-demand adherence and related factors in men who have sex with men who access HIV pre-exposure prophylaxis services via the internet]

Objective: To understand the compliancy to on-demand HIV pre-exposure prophylaxis (PrEP) and related factors in men who have sex with men (MSM) accessing to PrEP service through an Internet platform. Methods: A cross-sectional study method was used to recruit survey respondents through the Heer Health platform from July 6 to August 30, 2022, and a questionnaire survey on the current status of medication use was conducted in MSM who use PrEP through the platform and take medication on demand. The MSM's information collected in the survey mainly included socio-demographic characteristics, behavioral characteristics, risk perception characteristics, PrEP awareness and the status of dose taking. Univariate and multivariate logistic regression analyses were used to evaluate factors related with compliancy to PrEP. Results: A total of 330 MSM who met the recruitment criteria were included during the survey period, with a valid response rate of 96.7% (319/330) to the questionnaire survey. The age of the 319 MSM was (32.5±7.3) years. Most of them had education level of junior college or college and above (94.7%, 302/319), most of them were unmarried (90.3%, 288/319), most of them had full-time works (95.9%, 306/319), and 40.8% of them had average monthly income ≥10 000 yuan (130/319). The proportion of the MSM with good compliancy to PrEP was 86.5% (276/319). The results of univariate and multivariate logistic analyses showed that the MSM with good awareness of PrEP had relatively better compliancy to PrEP compared with those with poor awareness of PrEP (aOR=2.43, 95%CI:1.11-5.32). Conclusions: The compliancy to on-demand PrEP was good in MSM who accessed to the services through Internet platform, but there is still a need to strengthen PrEP promotion in MSM for the further improvement of PrEP compliancy and reduction of the risk for HIV infection in this population.

Modified transcrestal sinus floor elevation with concomitant implant placement in edentulous posterior maxillae with residual bone height of 5 mm or less: a non-controlled prospective study

The aim of this study was to describe a modified transcrestal sinus floor elevation (mTSFE) technique and to evaluate its clinical effectiveness and reliability when residual bone height is severely reduced. Forty-three maxillary edentulous patients who met the inclusion criteria were enrolled. All patients underwent the mTSFE technique; 66 dental implants were inserted simultaneously. Patient-reported outcomes were assessed 2 weeks after surgery. Prosthetic crowns were placed 6 months after surgery. Radiographic analyses and clinical analyses were conducted to assess the clinical effectiveness and feasibility of mTSFE during a follow-up period of 2-8 years. The mean vertical bone increase after surgery was 8.09 mm, and it decreased to 6.56 mm at 6 months after surgery. Two cases of membrane perforation occurred during surgery and one implant was lost in the third year after surgery; the survival rate at the implant level was 98.48%. No severe postoperative complication was reported and the subjective feeling of patients was acceptable. This mTSFE technique could simplify the operative procedure and might be helpful to reduce intraoperative trauma, as well as to alleviate postoperative discomfort.

[Yang Shoushan Medical Cases in the Wumen Medical School]

The unique manuscript, Yang Shoushan Medical Cases, is now held by the library of Nanjing University of Chinese Medicine.It is the medical cases collection of Yang Shoushan, a well-known doctor of Suzhou in the late Qing Dynasty.It was found that the number of medical cases and the details of each case recorded in this book were much more than that in his other existing medical writings. It greatly enriches the historical materials for the study of Yang's clinical characteristics and academic thought.Its compiler was Huang Shounan, a physician and calligrapher in Suzhou in the late Qing Dynasty and the early Republic of China.This book was not recorded as a book compiled by Huang Shounan before now. This book was believed to be completed in 1890.

Glucosylglycerol Extends Chronological Lifespan of the Budding Yeast via an Increased Osmolarity Response

Glucosylglycerol (GG) is an osmolyte that protects cells from extreme conditions. It is produced by sucrose phosphorylase, an enzyme that uses sucrose and glycerol as substrate. GG protects tissue integrity in desert plants during harsh conditions and guards cyanobacteria against high salinity (halotolerant). However, no extensive research has been conducted on the lifespan application of this compound on the yeast Saccharomyces cerevisiae. We designed this study to (1) characterize GG's effect on yeast chronological lifespan (CLS) and (2) to determine the mechanisms underlying its lifespan promotion on strain DBY746. The results obtained in our study confirm that GG causes increased longevity when administered at moderate doses (48 mM and 120 mM). In addition, we discovered that GG promotes yeast cell longevity by increasing the osmolarity of the culture medium. The maximum lifespan increased by approximately 15.38% and 34.6%, (i.e., 115.38 and 134.61) respectively, upon administration of GG at 48 mM and 120 mM concentrations. Elucidation of the mechanisms underlying this positive response suggests that GG promotes CLS by activities that modulate reactive oxygen species (ROS) generation, as evident in its increased ROS generation (mitohormesis). An increase in medium osmolarity caused by GG supplementation triggers ROS production and promotes longevity in the yeast (S. cerevisiae). An in-depth study on the potential application of this molecule in aging research is crucial; this will aid in expounding the mechanisms of this geroprotector and its longevity supportive tendencies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-023-01055-y.

[Miao Zunyi - his life, writings and students]

Miao Zunyi was an influential physician in the mid-Qing Dynasty. He was self-taught as he read a great amount of prescription books of traditional Chinese medicine. He was proficient in medical theories but flexible in treatment. It was recorded in Draft of Qing History that Miao Zunyi, Ye Tianshi and Xue Shengbai were named as "the three schools of Wuzhong". He began to write books in his later years. He wrote prefaces to Pulse Causes, Syndrome and Treatment (Mai Yin Zheng Zhi) and Wu Yi Hui Jiang. His existing works include Treatise on Febrile Disease (Shang Han Ji Zhu), Wen Re Lang Zhao, Song Xin Notes and Song Xin Medical Cases. Miao's Medical Cases and Song Xin Tang Yi An Jing Yan Chao. He had many remarkable students, such like Huang Tang, Guan Ding, Miao Song, and Shen Nianzu.

Coexistent diabetes is associated with the presence of adverse phenotypic features in patients with hypertrophic cardiomyopathy

Background

Type 2 diabetes mellitus (DM) is associated with worsened clinical outcomes in hypertrophic cardiomyopathy (HCM) patients. The reasons for this adverse prognostic association are incompletely understood. Although distinct entities both HCM and DM share common features of impaired myocardial energetics and coronary microvascular function.

Purpose

We sought to test the hypothesis that co-existent diabetes is associated with greater reductions in myocardial energetics and perfusion, and higher scar burden in HCM.

Research design and methods

Seventy-five age- and sex-matched participants with concomitant HCM and DM (HCM-DM, n=20), isolated HCM (n=20), isolated DM (n=20) and healthy volunteers (HV, n=15) underwent 31phosphorus magnetic resonance spectroscopy and cardiovascular magnetic resonance imaging. The HCM groups were matched for HCM phenotype. The DM groups were matched for diabetes treatment, duration, HbA1c, body mass index and hypertension comorbidity.

Results

ESC sudden cardiac death risk scores were comparable between the HCM groups (HCM: 2.2±1.5%, HCM-DM: 1.9±1.2%; p=NS) and sarcomeric mutations were equally common. HCM-DM had the highest NT-proBNP levels (HV: 42 ng/L [IQR: 35–66], DM: 118 ng/L [IQR: 53–187], HCM: 298 ng/L [IQR: 157–837], HCM-DM: 726 ng/L [IQR: 213–8695]; p&lt;0.0001). Left-ventricular ejection fraction, mass and wall thickness were similar between the HCM groups. HCM-DM displayed a greater degree of fibrosis burden with higher scar percentage, and lower global longitudinal strain compared to the isolated HCM. PCr/ATP was similarly decreased in the HCM-DM and DM (HV: 2.17±0.49, DM: 1.61±0.23, HCM: 1.93±0.38, HCM-DM: 1.54±0.27; p=0.0003). HCM-DM had the lowest stress myocardial blood flow (HV: 2.06±0.42 ml/min/g, DM: 1.78±0.45 ml/min/g, HCM: 1.74±0.44 ml/min/g, HCM-DM: 1.39±0.42 ml/min/g; p=0.004).

Conclusions

We show for the first time that HCM patients with DM comorbidity display greater reductions in myocardial energetics, perfusion, contractile function and higher myocardial scar burden and serum NT-proBNP levels compared to patients with isolated HCM despite similar LV mass and wall thickness and presence of sarcomeric mutations. These adverse phenotypic features may be important components of the adverse clinical manifestation attributable to a combined presence of HCM and DM.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Diabetes UK

Female sex and systolic blood pressure are independently associated with coronary microvascular dysfunction in asymptomatic adults with type 2 diabetes

Introduction

Coronary microvascular dysfunction is frequently reported in people with type 2 diabetes (T2D), is associated with reduced exercise capacity, and is a prognostic marker. Identifying modifiable risk factors associated with microvascular dysfunction may facilitate early intervention to improve outcomes in these patients.

Purpose

To identify independent determinants of myocardial perfusion reserve (MPR) in asymptomatic adults with T2D and no prevalent cardiovascular disease.

Methods

Prospective cross-sectional study. People with and without T2D and no signs, symptoms or evidence of cardiovascular disease underwent comprehensive phenotyping with echocardiography, coronary artery calcium scoring, and multiparametric cardiac MRI including adenosine stress and rest perfusion with automated pixel-wise myocardial blood flow (MBF) mapping. Participants with regional perfusion defects indicating obstructive coronary disease or silent myocardial infarct on late-gadolinium enhancement were excluded from analysis. Univariable and multivariable linear regression was performed to identify independent determinants of MPR.

Results

Two-hundred people with T2D (diabetes duration 11±8 years) were compared with 39 sex- and ethnicity-matched non-diabetic controls (Table 1). People with T2D had higher body mass index (BMI) and ambulatory 24-hour systolic blood pressure (SBP). There was evidence of concentric left ventricular (LV) remodelling (higher LV mass/volume), extracellular matrix expansion (higher ECV fraction), and both systolic and diastolic dysfunction (lower global longitudinal systolic strain and E/A ratio, respectively) in those with T2D. Resting MBF was similar between groups, but stress MBF tended to be lower in T2D compared to controls with significantly reduced MPR in T2Ds (2.87±0.86 vs 3.18±0.82, p=0.043). In univariable analysis, MPR correlated with sex, 24-hour SBP, and E/e' ratio. In a multivariable model adjusting for clinical (age, sex, smoking status, BMI, ambulatory SBP, diabetes duration, HbA1c, low-density lipoprotein, albuminuria) and imaging variables (E/e' ratio, LV mass/volume, global longitudinal strain, myocardial ECV, coronary calcium score) known to affect coronary perfusion, female sex (β=−0.227, p=0.013) and 24-hour SBP (β=−0.275, p=0.001) were the only variables independently associated with MPR.

Conclusion

Female sex is associated with coronary microvascular dysfunction in asymptomatic people with T2D but not LV mass or myocardial extracellular volume. Systolic BP is the only modifiable independent determinant of MPR and may be an early target for intervention to prevent heart failure development in these patients.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): National Institute for Health Research (NIHR) United Kingdom through a Research Professorship award (RP-2017-08-ST2-007).British Heart Foundation through a Clinical Research Training Fellowship award (FS/16/47/32190).

Clinical outcomes and myocardial recovery in energetics, perfusion and contractile function after valve replacement surgery in severe aortic stenosis patients with diabetes comorbidity

Background

Aortic stenosis (AS) and type 2 diabetes mellitus (DM) are increasingly frequent comorbidities in aging populations, and diabetes is associated with increased morbidity and mortality after aortic valve replacement (AVR). Although distinct pathological entities, AS and DM share common features of impaired myocardial energetics and coronary microvascular dysfunction (CMD). The mechanisms for the adverse prognostic association between AS and DM are incompletely understood.

Purpose

Utilising 31phosphorus magnetic resonance spectroscopy (31P-MRS) and CMR, we tested the hypotheses that the collective impact of severe AS and DM on the myocardium aggravates the impairment in energetics, function and perfusion.

Methods

Eighty-eight severe AS patients with (AS-DM) and without DM (Iso-AS) undergoing AVR and 15 healthy volunteers were recruited. Patients with coronary artery disease were excluded. Participants with AS underwent 31P-MRS and comprehensive CMR imaging 1 month prior to and 6 months after AVR.

Results

Demographic, biochemical and CMR/31P-MRS data are shown in Table-1. All groups were matched for age and sex distribution, with AS groups matched for surgical scores and frailty scores. NTproBNP levels were similarly elevated in AS groups. Left ventricular (LV) volumes and ejection fraction (EF) were similar between the groups, with no significant difference in LV mass or wall thickness between the AS groups. The baseline differences in myocardial energetics, stress myocardial blood flow (MBF) and global longitudinal strain (GLS) are shown in the Figure. AS-DM patients showed greater reductions in myocardial energetics (p&lt;0.0001), global stress MBF (p&lt;0.0001) and more significant reductions in GLS (p=0.001) than the Iso-AS patients. At 6 month post AVR both AS groups showed significant improvements in stress MBF and GLS. However, only the Iso-AS patients showed significant improvement in myocardial energetics.

AS patients were followed up for a median of 12 months. Cumulative incidence of the clinical events post AVR (composite of cardiovascular death, stroke, heart failure admission, infective endocarditis) were significantly higher in the AS-DM group than the Iso-AS group (Hazard Ratio: 3.35; 95% CI: 0.97–11.6; p=0.02).

Conclusion

Diabetes was associated with increased morbidity and mortality after AVR. We showed for the first time that the collective impact of T2DM and AS on the myocardium aggravates energetic impairment, CMD and contractile dysfunction. While myocardial recovery following AVR was associated with similar improvements in perfusion and contractile function in severe AS patients with and without T2DM, improvements in energetics were only detected in isolated AS patients. However, despite the significant improvements in contractile function and perfusion following AVR in diabetes patients, these parameters remained lower in the group with diabetes comorbidity compared to isolated AS patients.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Wellcome Trust

Improved diagnostic accuracy for apical hypertrophic cardiomyopathy

Introduction

The diagnosis of apical hypertrophic cardiomyopathy (ApHCM) is contingent on demonstrating apical maximum wall thickness (MWT) of ≥15mm; the same threshold as other HCM subtypes. However, the myocardium naturally tapers towards the apex in healthy individuals, so ≥15mm MWT is proportionately higher in the apex than in naturally thicker basal segments. Using cardiac magnetic resonance (CMR), relative ApHCM has been described (typical ECG features, loss of apical tapering, cavity obliteration but hypertrophy &lt;15mm). Wall thickness measurement using machine learning now exceeds human performance.

Purpose

We aimed to redefine the optimal diagnostic threshold for ApHCM using segment-specific criteria based on a large cohort of healthy control subjects.

Methods

Segmental wall thickness was measured using healthy subjects from the UK Biobank using a clinically validated machine learning algorithm1,2. A normative reference range was established for all 16 segments, conditioned to body surface area (BSA), sex and age. Derived segment-specific wall thickness thresholds were used to define optimal disease thresholds for patients clinically managed with overt (MWT ≥15mm) and relative ApHCM (MWT &lt;15mm, but typical ECG and imaging findings).

Results

4118 UK biobank subjects were used to define normal segmental thicknesses and reference ranges. These were applied to ApHCM (73 overt, 31 relative). There were no apical wall thickness age related differences. The upper limit of the 95% confidence interval corresponded to a combined maximum apical MWT for both males and females of 10.4mm using non-indexed measurement, or 5.6mm/m2 when indexed to BSA. Non-indexed segmental threshold identified 100% of ApHCM patients (true positives), 81% (25 of 31) relative ApHCM and 3% (115 of 4118) of healthy UK biobank subjects (false positives). Indexed segmental thresholds improved the diagnostic potential in relative ApHCM without an increase in false positives (100% of ApHCM patients, 84% (26 of 31) of relative ApHCM patients, and 3% healthy UK biobank (127 of 4118).

Conclusion

We propose new diagnostic criteria for ApHCM using segmental indexed apical wall thickness of &gt;5.6 mm/m2 to better identify inappropriate apical hypertrophy in those whose wall thickness does not meet current criteria for diagnosis.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation

Body mass index associated differences in cardiac stress energetics in type 2 diabetes

Background

Patients with T2D and heart disease have normal body mass index (BMI), suggesting that diabetes and obesity mediate cardiovascular change by different mechanisms. Changes in cardiac energy metabolism in lean diabetic patients during exercise stress have not been previously reported.

Objectives

We aimed to assess if there are BMI-associated differences in cardiac stress metabolism in patients with T2D.

Methods

Twenty-five overweight T2D patients (O-T2D) and eleven lean T2D patients (LnT2D), age- and ethnicity-matched and with no other comorbidities were studied. Patients were on oral hypoglycaemics only and were free of diabetes complications. Participants underwent rest and dobutamine stress phosphorus magnetic resonance spectroscopy (31P-MRS) and cardiovascular magnetic resonance (CMR) at 3T for the assessment of myocardial phosphocreatine to ATP ratio (PCr/ATP) as a measure of myocardial energetics, biventricular volumes, rest and stress left ventricular (LV) ejection fraction, global longitudinal shortening, and mitral in-flow E/A ratio for assessment of diastolic function and perfusion.

Intravenous Dobutamine was administered at a dose of 10μg/kg/min, increasing at 90 second intervals up to a maximum of 40 μg/kg/min to achieve a target heart rate of 65% of the age-predicted maximal heart rate. Mean rate pressure product (RPP) was recorded at rest and stress. Heart rate was maintained at target for the duration of the 31P-MRS and stress CMR cine, mitral in-flow and perfusion acquisitions.

Results

The cardiac volumes, systolic or diastolic function and LV mass were similar between LnT2D and O-T2D. Although the O-T2D patients had a numerically lower rest and stress PCr/ATP ratio, this did not reach statistical significance. Resting PCr/ATP was reduced in LnT2D and O-T2D patients similarly. However, LnT2D showed a greater reduction in PCr/ATP (stress PCr/ATP LnT2D 1.51±0.2 vs O-T2D 1.41±0.25, p=0.02) despite similar increases in RPP. Stress myocardial blood flow (MBF) was also significantly lower in the O-T2D patients. There were significant correlations of BMI with LV mass (r=0.35, p=0.03); stress LVEF (r=−0.34, p=0.04); stress MBF stress (r=−0.53, p=0.001) and stress E/A (r=0.46, p=0.01) (figure 1).

Conclusions

Despite their better stress perfusion and similar glycaemic control, LnT2D show worse metabolic reserve characterised by more significant decrements in energetics in response to hemodynamic stress compared to overweight patients with T2D. Higher BMI correlates inversely with stress myocardial blood flow and with stress left ventricular ejection fraction. The presence of these subtle alterations in measures of stress metabolism and perfusion might signify a distinct metabolic phenotype of “lean diabetic cardiomyopathy”. Future studies are needed to further delineate alterations in cardiac energy metabolism in lean and overweight/obese type 2 diabetes patients, and their role in the development of cardiac dysfunction.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Wellcome TrustBHF

Gestational diabetes, preeclampsia and the maternal heart

Background

Gestational diabetes mellitus (GDM) and preeclampsia (pE) are both associated with an increased risk of cardiovascular mortality and morbidity, including an increased risk of developing heart failure in later life. Both conditions are increasing in prevalence; GDM affects up to 12% and pE affects 3–5% of pregnancies worldwide. Compromised cardiac energy production is an important contributor to most forms of heart disease. The changes in myocardial energetics in GDM and pE have not been characterised previously.

Purpose

We sought to assess if women with GDM and women with pE in the third trimester of pregnancy exhibit adverse cardiac alterations in myocardial energetics, function or tissue characteristics.

Methods

Thirty-eight healthy pregnant (HP) women, thirty women with GDM and fifteen women with pE were recruited, matched for age and ethnicity. Participants underwent phosphorus magnetic resonance spectroscopy and cardiovascular magnetic resonance for assessment of myocardial energetics (phosphocreatine to ATP ratio (PCr/ATP)), tissue characteristics, biventricular volumes and ejection fractions, left ventricular (LV) mass, global longitudinal strain (GLS) and mitral in-flow E/A ratio.

Results

The biochemical characteristics and multiparametric MR results are given in Table 1.

The women in the GDM and the pE groups had higher body-mass index. There was a stepwise increase in the systolic and diastolic BP from the HP to the GDM to the pE group. There was no difference in NTproBNP concentrations between the groups. The gestational weight gain was higher in women with GDM and pE compared to the HP group.

The women in the GDM and the pE groups showed similar reductions in myocardial PCr/ATP ratios compared to HP group (Figure 1a), accompanied by lower LV end-diastolic volumes and higher LV mass (Figure 1b) and enhanced LV concentricity in both groups (Figure 1c). While LV ejection fractions were similar across the groups, the GLS was reduced in women with GDM and in women with pE (Figure 1d).

Conclusions

We show here for the first time that despite no prior diagnosis of diabetes or hypertension, women with GDM or pE manifest impaired myocardial contractility and higher LV mass, associated with reductions in myocardial energetics. These findings may aid our understanding of the long-term cardiovascular risks associated with these conditions.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Wellcome Trust

Evaluation of cardiac involvement in patients with clinical post-COVID-19 syndrome

Introduction

The underlying pathophysiology of Post-COVID-19 syndrome remains unknown, but increased cardiometabolic demand and state of mitochondrial dysfunction have emerged as candidate mechanisms. Cardiovascular magnetic resonance (CMR) provides insight into pathophysiological mechanisms underlying cardiovascular disease and 31-phosphorus magnetic resonance spectroscopy (31P-MRS) allows non-invasive assessment of the myocardial energetic state.

Purpose

We sought to assess whether Post-COVID-19 syndrome is associated with abnormalities of myocardial structure, function, perfusion and tissue characteristics or energetic derangement.

Methods

Prospective case-control study. A total of 20 patients with a clinical diagnosis of Post-COVID-19 syndrome (seropositive) and no prior underlying cardiovascular disease (CVD) and ten matching controls underwent 31P-MRS and CMR at 3T at a single time point. (Figure 1) All patients had been symptomatic with acute COVID-19, but none required hospital admission.

Results

Between the Post-COVID-19 syndrome patients and matched contemporary controls there were no differences in myocardial energetics (phosphocreatine to ATP ratio), in cardiac structure (biventricular volumes, left ventricular mass), function (biventricular ejection fractions, global longitudinal strain), tissue characterization (T1 and extracellular volume [ECV] fraction mapping, late gadolinium enhancement) or perfusion (myocardial rest and stress blood flow, myocardial perfusion reserve). One patient with Post-COVID-19 syndrome showed subepicardial hyperenhancement on the late gadolinium enhancement imaging compatible with prior myocarditis, but no accompanying abnormality in cardiac size, function, perfusion, ECV, T1, T2 mapping or energetics. This patient was excluded from statistical analyses. (Table 1)

Conclusion

In this study, the overwhelming majority of patients with a clinical Post-COVID-19 syndrome with no prior CVD did not exhibit any abnormalities in myocardial energetics, structure, function, blood flow or tissue characteristics.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Welcome Trust Clinical Career Development Fellowship (221690/Z/20/Z);NIHR-UKRI COVID-19 Rapid Response Rolling Call (COV0254)ESC Training Grant

Convolutional neural network transformer (CNNT) for free-breathing real-time cine imaging

Funding Acknowledgements

Type of funding sources: None.

Background

Real-time cine imaging does not require breath-holding and is a robust cine imaging technique in the presence of irregular heartbeats. It is a good alternative to the conventional breath-hold retro-gated cine for simplified acquisition and improved patient comfort. Real-time acquisition is achieved with the single-shot BSSFP readout without retro-gating. To maintain good temporal and spatial resolution, higher acceleration (e.g. &gt;4x parallel imaging) is required. As a result, the real-time cine images experience reduced signal-to-noise ratio (SNR), which limits its clinical acceptance.

Purpose

We developed a novel deep learning model architecture, the Convolutional Neural Network Transformer (CNNT), to improve the quality of real-time cine, under 4x, 5x and 6x acceleration.

Method

Convolutional Neural Networks (CNN) are widely used in CMR research to process cardiac images. Cardiac images are often acquired as a time series with strong inter-phase correlation. We combined the CNN with the more recent transformer model to develop a novel CNNT architecture. It takes in the entire 2D+T time series as input and has advantages of CNN for efficient computation and spatial invariance. It further inherits the advantages of attention layer in the transformer and is able to efficiently utilize the temporal correlation within a time series.

A CNNT model is developed to improve the SNR of real-time cine imaging. N=10 patients were scanned at a heart center, with 4x, 5x and 6x acceleration. Typical imaging parameters are: FOV 360×270mm2, flip angle 50°, acquired matrix size 160×90 for R=4 acceleration, 192×108 for R=5 and 6, temporal resolution 40ms for R=4, 42ms for R=5 and 35ms for R=6. The real-time images went through a TGRAPPA reconstruction [1] and the CNNT model. The SNR of TGRAPPA was measured with SNR units [2]. The Monte-Carlo pseudo-replica test was used to measure SNR for the CNNT model. For every cine series, two phases were picked for the end-systole and end-diastole. For every image picked, two region-of-interests were drawn in the myocardium and in the LV blood pool. The CNNT model was deployed inline on the MR scanner using the Gadgetron InlineAI [3].

Results

Figure 1 gives real-time cine images for three accelerations, reconstructed with TGRAPPA and CNNT. The parallel imaging TGRAPPA reconstruction suffers significant SNR loss from elevated g-factor and less acquired data. The deep learning CNNT model recovered SNR even at the very high 6x acceleration, without observed loss of boundary sharpness.

Table 1 lists the SNR measurement results. The TGRAPPA SNR decreased ∼4x from R=4 to R=6 for both the blood and myocardium. For the blood, the CNNT increased the SNR by 170%, 335%, 371% at R=4, 5 and 6. For the myocardium, the SNR increases were 335%, 634% and 828%.

Conclusion

We developed a convolutional neural network transformer model to recover the SNR for real-time cine imaging at higher acceleration.

CNNT DB-LGE: free-breathing dark blood late enhancement imaging using the convolutional neural network transformer speeds acquisition by 50%

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Supported in part by the Division of Intramural Research of the National Heart, Lung, and Blood Institute, National Institutes of Health (grants Z1A-HL006214-05 and Z1A-HL006242-02).

Background

Dark blood late gadolinium enhancement (DB-LGE) imaging shows superior delineation of myocardial infarction (MI), especially at the sub-endocardial boundary. Our previous study [1] developed a free-breathing DB-LGE with the single shot SSFP readout, phase sensitive inversion recovery (PSIR) reconstruction, and respiratory motion corrected averaging. To compensate the potential signal-to-noise ratio loss, our previous DB-LGE doubled the measurements, thereby increasing the acquisition time.

Purpose

In this study, we developed a deep learning image enhancement model using a novel neural network architecture called the convolutional neural network transformer (CNNT) to improve the image quality of DB-LGE and to reduce the acquisition time by decreasing the number of measurements.

Methods

A novel image enhancement model was developed using a novel network architecture called the Convolutional Neural Network Transformer (CNNT) proposed by us. This architecture is suitable for the 2D+Time CMR acquisition, by exploiting the temporal correlation between images over multiple averages.

The evaluation was first retrospectively conducted on a cohort of 12 patients acquired with the original protocol [1] using the full 16 measurements. For every subject, a complete short-axis stack (typically 12 slices) was acquired to cover the entire left ventricular. The imaging data was reconstructed in three ways. Original: using all acquired 16 measurements. This is our base-line protocol. Original 50%: using only the first 8 measurements. CNNT 50%: using only the first 8 averages, but performing the CNNT deep learning image enhancement before MOCO PSIR reconstruction. Two experienced imaging researchers (PK and MF, &gt;10 years of experience for both) scored all DB-LGE images for the overall quality, diagnostic confidence and delineation of MI/boundaries (5 = excellent, 4 = good, 3 = fair, 2 = poor, and 1 = non-diagnostic). The CNNT DB-LGE was deployed to the MR scanner using the Gadgetron InlineAI [2].

Results

Figure 1 gives examples of DB-LGE with three reconstruction methods. The CNNT image has higher SNR and well delineated MI. The Original images with the longest acquisition have good quality and the Original-50% acquired with 8 measurements are good quality but have reduced SNR. The mean scores for overall image quality, diagnostic confidence and MI delineation of two reviewers were 4.88±0.23, 4.88±0.23, 4.83±0.25 for CNNT and 4.96±0.14, 4.96±0.14, 4.67±0.39 for the original approach. No significant differences were found between the original and the CNNT (P&gt;0.15 for all).

Figure 2 shows an acute MI patient prospectively acquired with the 50% scan time reduction, with and without the CNNT enhancement. The resulting PSIR images well delineate the MVO due to the acute MI, with improved SNR.

Conclusion

A novel CNNT model was proposed and evaluated to speed up the free-breathing MOCO DB LGE by 50% without sacrificing image quality.

Improving the diagnostic accuracy of apical hypertrophic cardiomyopathy using machine learning

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Dr Hughes is supported by the British Heart Foundation (grant number FS/17/82/33222).

Introduction

The imaging criteria for diagnosis of apical hypertrophic cardiomyopathy (ApHCM) is a maximum wall thickness (MWT) ≥15mm. CMR enables detection of subtle phenotypic features (e.g. loss of apical tapering, cavity obliteration) and coupled with characteristic electrocardiogram changes, ApHCM can be diagnosed without overt hypertrophy. However, these patients are not captured by current diagnostic criteria.

Purpose

We sought to use a machine learning tool to quantify wall thickness and identify patients with ‘relative’ ApHCM that do not reach current diagnostic thresholds.

Methods

CMR images from 4118 healthy participants from the UK Biobank were segmented automatically with a clinically validated machine learning algorithm and wall thickness measured at all point in the myocardium by solving a solution to Laplace’s equation. MWT were pooled into 16 AHA segments and indexed to body surface area (BSA). The non-indexed and indexed segmental upper limit of normal was calculated as the mean + 3 standard deviations (the equivalent of 95% confidence interval after correcting for multiple [16] comparisons using the Bonferroni method).

Results

73 overt ApHCM subjects (MWT&gt;15mm) and 31 relative ApHCM subjects underwent CMR scanning. In healthy controls, the non-indexed (and indexed) upper limits were calculated for the apical-anterior 10.2mm (5.2 mm/m2), apical-septal 11.1mm (5.6 mm/m2), apical-inferior 10.5mm (5.3 mm/m2) and apical-lateral 10.1mm (5.2 mm/m2) segments. With a non-indexed cut-off, all (73 of 73) overt ApHCM and 84% (26 of 31) relative ApHCM were classified as having an abnormally thick apex. 3% (127 of 4118) of the healthy UK Biobank cohort were classified as abnormal, as expected. Using an indexed cut-off, all overt ApHCM and 87% (27/31) relative ApHCM were classified as abnormal, and 3% (123 of 4118) of the healthy UK Biobank cohort were misclassified.

Conclusion

We can successfully classify 87% of relative ApHCM patients from a normative reference range derived from a large cohort of healthy patients – a significant improvement on existing methods. We show that the specificity and sensitivity is increased when MWT is indexed to BSA. For practical clinical application, we recommend a cut-off of 10mm or an indexed cut-off of 5mm/m2 in any apical segment to diagnose apical LVH. Overt and relative apical HCM examplesHealthy controls AHA maps (non-indexed)

Speeding up cardiac MR segmentation with semi-supervision: applications in cine imaging

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): This material is based upon work supported by the Google Cloud Research Credits program with the award GCP19980904.

Background

Segmentation is an important postprocessing step in cardiac magnetic resonance (CMR) imaging that enables quantitative assessment of functional parameters. Deep learning can automate the segmentation process, producing accurate contours of cardiac structures while reducing the time required to analyze images and the interobserver variation compared to manual analysis. However, common approaches to training neural networks (NNs) require large amounts of labeled data, which is costly to generate and slows down the development of CMR segmentation NNs for new applications. Semi-supervision is an approach to alleviate this labeling burden by relying on abundant unlabeled data and a smaller amount of labeled data to train NNs.

Purpose

We propose a novel semi-supervised method to train CMR segmentation NNs. We use the proposed method to train NNs to segment the left ventricle in CMR cine images. Ultimately, we aim to show that semi-supervision can drastically reduce the amount of labeled data required to develop machine learning segmentation applications for CMR while maintaining high performance.

Methods

Our dataset consists of 1,208 short-axis cine CMR images and 1,244 long-axis cine CMR images. An expert annotator manually segmented the endocardium on the end-diastolic and end-systolic short-axis and long-axis images and the epicardium on the end-diastolic short-axis images. We split the dataset randomly by patient into 60% training, 20% validation, and 20% testing data. We train semi-supervised segmentation networks using a supervised cross-entropy loss to learn from the labeled training data and a cosine embedding loss in addition to a pseudo-labeling step to learn from the unlabeled training data. To evaluate how performance changes with different amounts of labeled training data, we vary the percent of training data that has labels from &lt;1%-100%. We evaluate the predicted segmentation masks using the Dice coefficient.

Results

Using only 100 labeled image slices, the semi-supervised segmentation NNs achieve a mean Dice coefficient within 1.10% of networks trained with fully labeled training sets, corresponding to &gt;85% reduction in required labeled training data (Table 1). The proposed semi-supervised method improves performance over naïve training by 6.21% for the most limited labeled data setting (i.e., 10 labeled image slices; Figure 1).

Conclusion

We have shown that NNs trained with limited labeled data achieve high performance on left ventricle segmentation in short-axis and long-axis CMR cines. The proposed approach is flexible and broadly applicable to different CMR segmentation tasks, enabling rapid development of segmentation networks for many cardiac structures and applications. Table 1Figure 1

Pharmacological inhibition of eIF2alpha phosphorylation by integrated stress response inhibitor (ISRIB) ameliorates vascular calcification in rats

Vascular calcification (VC) is an independent risk factor for cardiovascular events and all-cause mortality with the absence of current treatment. This study aimed to investigate whether eIF2alpha phosphorylation inhibition could ameliorate VC. VC in rats was induced by administration of vitamin D3 (3×10(5) IU/kg, intramuscularly) plus nicotine (25 mg/kg, intragastrically). ISRIB (0.25 mg/kg·week), an inhibitor of eIF2alpha phosphorylation, ameliorated the elevation of calcium deposition and ALP activity in calcified rat aortas, accompanied by amelioration of increased SBP, PP, and PWV. The decreased protein levels of calponin and SM22alpha, and the increased levels of RUNX2 and BMP2 in calcified aorta were all rescued by ISRIB, while the increased levels of the GRP78, GRP94, and C/EBP homologous proteins in rats with VC were also attenuated. Moreover, ISRIB could prevent the elevation of eIF2alpha phosphorylation and ATF4, and partially inhibit PERK phosphorylation in the calcified aorta. These results suggested that an eIF2alpha phosphorylation inhibitor could ameliorate VC pathogenesis by blocking eIF2alpha/ATF4 signaling, which may provide a new target for VC prevention and treatment.

[Effect of tourniquet on morphology and stiffness of quadriceps in patients receiving total knee arthroplasty: a randomized controlled trial]

Objective: To evaluate tourniquet effect on the morphology and stiffness of quadriceps in patients receiving total knee arthroplasty (TKA). Methods: Total of 80 patients with primary knee osteoarthritis receiving unilateral primary TKA from August 2020 to June 2021 in Peking University Third Hospital were enrolled in this randomized controlled trial. The patients were randomly divided into tourniquet group and non-tourniquet group (40 cases in each group). The study measured and compared postoperative thickness and stiffness of quadriceps, as well as circumference of the affected thigh in two groups. Results: There were 11 males and 29 females in tourniquet group, 9 males and 31 females in non-tourniquet group, with mean age of (69.1±5.1) years and (67.4±5.3) years, respectively. There was no significant difference in demographic information such as gender, age and BMI (all P<0.05). Postoperative thickness of quadriceps, stiffness of quadriceps and circumference［x¯±s or M （Q₁，Q₃）］of the affected thigh in all patients were (2.76±0.69) cm, 25.20 (17.83, 32.90) m/s, 54.00 (51.13, 56.00) cm. These outcomes in tourniquet and non-tourniquet group［x¯±s or M （Q₁，Q₃）］were (2.78±0.76) cm and (2.73±0.61) cm, 24.00 (17.15, 33.13) m/s and 25.20 (18.68, 32.85) m/s, 54.00 (49.75, 55.00) cm and 54.50 (52.13, 57.53) cm, respectively; no significant deference was found in these indexes between the two groups (all P>0.05). Conclusion: Tourniquet has no significant effect on morphology and stiffness of quadriceps in patients undergoing TKA.

[Status of HVPG clinical application in China in 2021]

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

POS0549 IMBALANCED Tfr/Tfh IN PERIPHERAL BLOOD OF NEW-ONSET RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is a kind of autoimmune disease characterized with chronic aggressive arthritis, presence of abnormal antibodies and persistent synovitis[1]. However, the pathogenesis of RA remained unclear by now. Several observations have showed that the breakdown of immune tolerance was involved in the development of RA. T follicular regulatory (Tfr) cells and T follicular helper (Tfh) cells, as a new subset of CD4+T cell, can exert an opposite effect in the regulation of humoral immunity[2]. Intensive researches have showed that the imbalance of Tfr/Tfh cell is related to the pathogenesis and development of autoimmune disease. There is still a lack of understanding of the relationship between Tfr/Tfh and RA, which needs further exploration.

Objectives

To detect the expression of Tfh and Tfr cells in thr peripheral blood of patients with new-onset RA and healthy controls, and to explore the role of Tfh and Tfr cells in the pathogenesis and development of RA.

Methods

We enrolled 26 patients with new-onset RA who hospitalized at the Second Hospital of Shanxi Medical University from the June 2021 to the November 2021. And 17 age and gender-matched healthy adults were anticipated as controls. The absolute number of Tfh and Tfr cells in peripheral blood was detected by flow cytometry. Disease activity indicators were collected including erythrocyte sedimentation rate (ESR, mm/h) and Disease Activity Score in 28 joints (DAS28). Then we compared the expression of Tfh and Tfr cells between the patients and healthy controls and conducted the correlation analysis with disease activity.

Results

There was significant decreased level of Tfr cells in the patients with new-onset RA compared with healthy controls (P<0.001) and a lower ratio of Tfr/Tfh in the patients (P<0.01). The reduced Tfr cells and Tfr/Tfh were significant negative correlation with the disease activity indicators including ESR and DAS28 (r=-0.305, P=0.033). There was no statistically significant in the absolute number of Tfh cells between patients and healthy controls, but the level of Tfh cell showed an increasing trend in new-onset RA.

Conclusion

The results we investigated here showed that new-onset RA exhibited an imbalance of Tfr/Tfh, specifically reduced Tfr cells, compared with healthy controls, which were negatively correlated with higher disease activity in RA. It was likely that the imbalance of Tfr/Tfh in peripheral blood played an important role in the development of RA, which may be a target to treat RA.

Table 1.

A summary of data of all enrolled patients with RA and healthy controls

HC(n=17)New-onset RA(n=26)P valueAge(years)51.94±13.0355.88±13.56P=0.35Sex(male/female)4/137/19P=0.81ESR(mm/h) a-54.85±32.71-DAS28 a-5.09±1.56-Tfh cell count(cell/UL)b43.156(23.277,106.638)83.914(38.133,119.662)0.214Tfr cell count(cell/UL)b1.422(0.882,1.893)0.441(0.116,2.888)0.025*Tfr/Tfhb0.030(0.014,0.049)0.011(0.001,0.024)0.001**

a Results are expressed as the mean ± standard error. b Results are expressed as the median(Q1,Q3).

Normally distributed continuous variables were analyzed by the independent-samples Student’s t-test. And nonparametric variables were analyzed by Mann–Whitney U test

Figure 1.

The differences of Tfr and Tfh cells in peripheral blood between the healthy controls and patients with RA. Tfr cells were higher in new-onset RA leading to an imbalance of Tfr/Tfh. Statistical analyses were performed by the Mann-Whitney U test. (*P<0.05, **P<0.01)

Figure 2.

The correlation of disease activity with the level of Tfr cells and Tfr/Tfh. Tfr cells and Tfr/Tfh were negative associated with ESR and DAS28. Statistical analyses were performed by the Spearman correlation analysis.

References

[1]Sparks, J.A. Rheumatoid Arthritis [J]. Ann Intern Med, 2019, 170(1).DOI: 10.7326/AITC201901010.

[2]Deng, J., Y. Wei, V.R. Fonseca, L. Graca, and D. Yu. T follicular helper cells and T follicular regulatory cells in rheumatic diseases [J]. Nat Rev Rheumatol, 2019, 15(8): 475-490.DOI: 10.1038/s41584-019-0254-2.

Disclosure of Interests

None declared.

[The influence of subjective comfort of working environment on occupational stress of railway station workers]

Objective: To explore the influential factors of job stress suffered by workers in railway stations, the level of job stress of were measured and subjective comfort of employees targeting to working environment were reported. Methods: In March 2019, a cluster sampling study was designed to collect the personal characteristics, job characteristics and subjective comfort degree of working environment of 432 employees in Chongqing railway stations. Meanwhile, job stress was assessed using the effort-reward imbalance scale. Chi-square test was used to compare the difference of occupational stress detection rate among different stratified factors such as occupational characteristics. Logistic regression was applied to analyze the influential factors of occupational stress. Results: The detection rate of job stress of workers in the railway stations was 31.02% (134/432) . The detection rate of job stress was higher among the divorced workers in railway stations, those earning less than 5, 000 yuan per month, those with 10-20 years' length of service, those who worked as a conductor and other workers including baggageman, station master on duty and assistant engineer (χ(2)=9.61, 14.76, 23.28, 11.06, P=0.008, 0.002, 0.000, 0.011) . The detection rate of job stress was higher among those whose working environment subjective feelings were uncomfortable, the differences were statistically significant (P<0.001) . The results showed that the occupational stress of the staff in the railway stations was influenced by their subjective feeling of air quality, noise and Space Layout (P<0.05) . The risk factors of occupational stress were air quality, noise and uncomfortable space layout (OR=0.571, 0.068, 0.441, P=0.051, 0.054, 0.007) . Conductor, other (Bellboy, Duty Station Master, assistant engineer) were the risk factors of occupational stress (OR=1.884, 2.703, P=0.065, 0.019) . The employees of station A and station B were the risk factors of occupational stress (OR=4.681, 1.811, P=0.002, 0.067) . Conclusion: The higher detection rate of job stress of workers in the railway stations is correlated with the subjective comfort degree of the working environment of the workers.

Coronary microvascular dysfunction is only detectable in type 2 diabetes in the presence of obesity

Background

Heart failure (HF) is a leading cardiovascular complication of type 2 diabetes (T2D). Coronary microvascular dysfunction (CMD) precedes HF in diabetes and carries important prognostic information. CMD is also evident in metabolically healthy obese individuals without diabetes or hypertension. Whether diabetes causes CMD in the absence of obesity is uncertain. The interrelation among visceral adiposity and CMD has not been assessed previously.

Objectives

We sought to better understand the links between visceral and epicardial adipose tissue (VAT and EAT respectively) distribution, insulin resistance with myocardial perfusion, energetics and function in asymptomatic lean (LnT2D) and overweight/obese T2D patients (ObT2D) without cardiovascular disease.

Methods

62 participants [27 Ob-T2D, 15 Ln-T2D, and 20 overweight controls] were recruited. Subjects underwent cardiac and abdominal magnetic resonance imaging and 31P-magnetic resonance spectroscopy, for measurements of EAT and VAT areas, rest and adenosine stress myocardial blood flow (MBF), cardiac function and phosphocreatine to ATP ratio (PCr/ATP). Fasting blood samples were taken for plasma homeostasis model assessment of insulin resistance (HOMA-IR) index calculations.

Results

The biochemical characteristics and multiparametric MR results are given in Table 1 and results of Pearson's regression analysis in the entire study population are given in Table 2.

Stress MBF was lowest in ObT2D, while rest MBF was highest in LnT2D. Left ventricular ejection fraction (LVEF) and myocardial PCr/ATP were similarly reduced in diabetes groups. In the absence of obesity, there was no significant increase in VAT, EAT or HOMA-IR in T2D patients compared to controls. BMI and VAT, negatively correlated with LVEF, and strain parameters. PCr/ATP correlated with LVEF, but not HOMA-IR. BMI, EAT and VAT all correlated significantly with HOMA-IR, and HOMA-IR correlated with cardiac functional parameters. There was no association between HOMA-IR and myocardial perfusion.

Conclusions

In this study CMD was only evident in ObT2D patients, with normal rest and stress MBF in LnT2D patients. Despite normal perfusion and no significant increase in insulin resistance, LVEF and myocardial PCr/ATP were similarly reduced in LnT2D and ObT2D, and PCr/ATP correlated with LVEF. This suggests that alterations in cardiac energy metabolism are mechanistically more relevant for the pathophysiology of diabetic cardiomyopathy in LnT2D patients. In the absence of correlation between insulin resistance and myocardial perfusion, factors like inflammation and altered adipokine profile may play important roles for the pathophysiology of CMD in ObT2D patients. A better understanding of the underlying pathophysiological mechanisms of diabetic cardiomyopathy in LnT2D and ObT2D may help to develop contemporary tailored treatment and prevention strategies to tackle excess heart failure risk.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): BHFWellcome trust Table 1Table 2

Mechanistic insights from a multiparametric magnetic resonance imaging study regarding the role of sodium glucose co-transporter 2 inhibitors

Background

Type 2 diabetes (T2D) is associated with an increased risk of heart failure (HF) and cardiovascular (CV) mortality. Sodium–glucose-co transporter-2 (SGLT2) inhibitors reduce the risk of major adverse CV events and hospitalisation for HF in T2D patients with high cardiovascular risk, despite only a modest improvement in glycemic control. Restoring cellular energy homeostasis and reversing adverse cardiac remodelling in diabetes have been speculated as a potential metabolic modulatory effect of SGLT2 inhibitors leading to their beneficial CV outcomes. Myocardial energy deficient states can be detected non-invasively by 31-phosphorus magnetic resonance spectroscopy (31P-MRS).

Objectives

Utilising cardiovascular magnetic resonance imaging (CMR) and 31P-MRS in a single centre longitudinal cohort study, we aimed to investigate the effects of the selective SGLT2 inhibitor empagliflozin on myocardial energetics, function, perfusion, and myocardial cellular volume in patients with T2D.

Methods

Eighteen consecutive T2D patients who were commenced on empagliflozin in cardiometabolic optimisation clinics underwent CMR and 31P-MRS scans before and after twelve-week empagliflozin treatment, and plasma N-terminal pro hormone B-type natriuretic peptide (NT-proBNP) levels were measured. Ten controls with no diabetes underwent an identical 31P-MRS and CMR protocol on a single visit.

Results

When compared to controls, patients with T2D showed: lower myocardial energetics (1.52±0.40 vs 2.20±0.5, p=0.0005), lower stress myocardial blood flow (1.60±0.50 vs 2.10±0.50, p=0.02) and lower left ventricular ejection fraction (52±13% vs 63±4%, p=0.01). Treatment with empagliflozin led to significant improvements in myocardial energetics (PCr/ATP: 1.52 to 1.76, p=0.009). This was accompanied by a relative 13% improvement in left ventricular ejection fraction (p=0.001), 3% improvement in global longitudinal strain (p=0.01), 61% reduction in NTproBNP (p=0.05), and 9% reduction in myocardial cell volume (p=0.04). No significant change in myocardial blood flow or diastolic strain was detected.

Conclusions

For the first time, we demonstrate that empagliflizon improves myocardial energetics and function, reduces myocardial cellular volume, and reduces NT-proBNP levels in patients with T2D.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation PCr/ATPLVEF

[The Ding medical family in Jiangpu in the Ming and the Qing Dynasties]

The Jiangpu Ding family was a Gentry Family with many scholars in Nanjing, running through the Ming and the Qing Dynasties. Successful in both medicine and the imperial examination, talents in various fields emerged in large numbers over more than ten generations. Their practice of medicine began with Ding Zhongbao from the original generation, and the second generation of Ding Yi was promoted from a doctor to a local medical officer. From the fifth generation, Ding Feng, became a famous doctor.However, only Ding Yi and Ding Feng were professional doctors in the whole family lineage. The Ding's were still a Gentry Family in essence. The feature of the family was that the Ding's kept their medical background and interests although there existed no professional doctors after Ding Feng in the middle of the Ming Dynasty. This is because the Ding family expected their heirs to acquire medical skills. The Ding's had a number of medical books handed down, such as The Collection of Prescriptions, The Collection of Jade Letters of Pox Department and The Eight Things of Practicing Medicine.

Dark blood ischemic LGE segmentation using a deep learning approach

Funding Acknowledgements

Type of funding sources: None.

Introduction

The extent of ischemic scar detected by Cardiac Magnetic Resonance (CMR) with late gadolinium enhancement (LGE) is linked with long-term prognosis, but scar quantification is time-consuming. Deep Learning (DL) approaches appear promising in CMR segmentation.  Purpose: To train and apply a deep learning approach to dark blood (DB) CMR-LGE for ischemic scar segmentation, comparing results to 4-Standard Deviation (4-SD) semi-automated method. Methods: We trained and validated a dual neural network infrastructure on a dataset of DB-LGE short-axis stacks, acquired at 1.5T from 33 patients with ischemic scar. The DL architectures were an evolution of the U-Net Convolutional Neural Network (CNN), using data augmentation to increase generalization. The CNNs worked together to identify and segment 1) the myocardium and 2) areas of LGE. The first CNN simultaneously cropped the region of interest (RoI) according to the bounding box of the heart and calculated the area of myocardium. The cropped RoI was then processed by the second CNN, which identified the overall LGE area. The extent of scar was calculated as the ratio of the two areas. For comparison, endo- and epi-cardial borders were manually contoured and scars segmented by a 4-SD technique with a validated software. Results: The two U-Net networks were implemented with two free and open-source software library for machine learning. We performed 5-fold cross-validation over a dataset of 108 and 385 labelled CMR images of the myocardium and scar, respectively. We obtained high performance (&gt; ∼0.85) as measured by the Intersection over Union metric (IoU) on the training sets, in the case of scar segmentation. With regards to heart recognition, the performance was lower (&gt; ∼0.7), although improved (∼ 0.75) by detecting the cardiac area instead of heart boundaries. On the validation set, performances oscillated between 0.8 and 0.85 for scar tissue recognition, and dropped to ∼0.7 for myocardium segmentation. We believe that underrepresented samples and noise might be affecting the overall performances, so that additional data might be beneficial. Figure1: examples of heart segmentation (upper left panel: training; upper right panel: validation) and of scar segmentation (lower left panel: training; lower right panel: validation). Conclusion: Our CNNs show promising results in automatically segmenting LV and quantify ischemic scars on DB-LGE-CMR images. The performances of our method can further improve by expanding the data set used for the training. If implemented in a clinical routine, this process can speed up the CMR analysis process and aid in the clinical decision-making. Abstract Figure.

POS0396 THE LEVEL OF PERIPHERAL REGULATORY T CELLS IS ASSOCIATED WITH THE CHANGES OF INTESTINAL MICROBIOTA IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) is a systemic autoimmunity inflammation disease characterized with chronic aggressive arthritis and the presence of abnormal antibodies. Several observations showed that the breakdown of immune tolerance caused by many complex interactions was involved in the development of RA[1]. However, the pathogenesis of RA remained unclear. It has been confirmed that the imbalance of Th17 and Treg cells play a crucial role in destroying immune tolerance [2]. Besides, researches showed that intestinal microbiota can influence host immunity by acting on the immune cells to play pro-inflammatory or anti-inflammatory effect, and in turn immune system can also regulate the microbiota[3, 4]. Thus, a frontier point of view in the field of rheumatism, immune microecology, was proposed, which is a novel concept for the breakdown of immune tolerance. Studies have confirmed that there was an imbalance of intestinal microbiota in patients with RA [4]. But the relationship between the CD4+T subsets cells and intestinal microbiota in RA is unknown.

Objectives:

We detected and compared the absolute number of CD4+T cells subsets in the peripheral blood and the proportion or abundance of intestinal microbiota in patients with RA and healthy adults, and then analyzed the relationship between them to explore the role of CD4+T cells subsets and intestinal microbiota in the pathogenesis of RA.

Methods:

We collected the sample of stool and blood from 15 patients with RA hospitalized at the Second Hospital of Shanxi Medical University and 8 age and gender-matched healthy controls(HC). The absolute number of CD4+T cells subsets including Th1, Th2, Th17 and Treg cells were detected by flow cytometry. The 16S rRNA in the stool specimens were sequenced by the Roche/45 high-throughput sequencing platform. We analyzed whether there was correlarion between CD4+T subsets cells and intestinal microbiota.

Results:

Patients with RA had a higher level of Christensenellaceae and a lower level of Pseudomonadaceae as compared with those of HCs at the family level (p<0.05). And at the genus level, the patients with RA had higher levels of Ruminococcus torques, Christensenellaceae R-7, Ruminiclostridium 9 and Ruminococcus 1 compared with those of HCs (p<0.05) (Figure 1).And the Ruminococcus torques at the genus level was negative correlated with the absolute number of Treg cells (p<0.001) (Figure 2).

Conclusion:

The results here suggested that there were different proportion or abundance of intestinal microbiota between the patients with RA andHCs. And the changes of intestinal microbiota such as Ruminococcus torques were associated with Treg cells, further indicating that the imbalance of intestinal microbiota in RA can destory the immune tolerance. The above results uncovered that the intestinal microbiota had immunomodulatory function, which may be the upstream mechanism participated in the pathogenesis of RA.

References:

[1]Weyand CM, Goronzy JJ. The immunology of rheumatoid arthritis. Nat Immunol 2021, 22(1): 10-18.

[2]Weyand CM, Goronzy JJ. Immunometabolism in the development of rheumatoid arthritis. Immunol Rev 2020, 294(1): 177-187.

[3]Brown EM, Kenny DJ, Xavier RJ. Gut Microbiota Regulation of T Cells During Inflammation and Autoimmunity. Annu Rev Immunol 2019, 37: 599-624.

[4]du Teil Espina M, Gabarrini G, Harmsen HJM, Westra J, van Winkelhoff AJ, van Dijl JM. Talk to your gut: the oral-gut microbiome axis and its immunomodulatory role in the etiology of rheumatoid arthritis. FEMS Microbiol Rev 2019, 43(1).

Figure 1.

At the family level (a-b) and the genus level(c-f), the relative abundance of intestinal microbiota in patients with RA and HCs were different. Data were expressed as median (Q1, Q3) and analyzed by Wilcoxon test. (*** P < 0.001, **P < 0.01 and *P < 0.05).

Figure 2.

A heatmap shows the correlation between the intestinal microbiota and CD4+T cells in patients with RA, and Ruminococcus torques at the genus level was negative related with Treg cells. (Colors indicate the Spearman rank correlation, *** P < 0.001).

Disclosure of Interests:

None declared

M-BLUE protocol for coronavirus disease-19 (COVID-19) patients: interobserver variability and correlation with disease severity

AIM

To retrospectively evaluate the interobserver variability of intensive care unit (ICU) practitioners and radiologists who used the M-BLUE (modified bedside lung ultrasound in emergency) protocol to assess coronavirus disease-19 (COVID-19) patients, and to determine the correlation between total M-BLUE protocol score and three different scoring systems reflecting disease severity.

MATERIALS AND METHODS

Institutional review board approval was obtained and informed consent was not required. Ninety-six lung ultrasonography (LUS) examinations were performed using the M-BLUE protocol in 79 consecutive COVID-19 patients. Two ICU practitioners and three radiologists reviewed video clips of the LUS of eight different regions in each lung retrospectively. Each observer, who was blind to the patient information, described each clip with M-BLUE terminology and assigned a corresponding score. Interobserver variability was assessed using intraclass correlation coefficient. Spearman's correlation coefficient analysis (R-value) was used to assess the correlation between the total score of the eight video clips and disease severity.

RESULTS

For different LUS signs, fair to good agreement was obtained (ICC = 0.601, 0.339, 0.334, and 0.557 for 0-3 points respectively). The overall interobserver variability was good for both the five different readers and consensus opinions (ICC = 0.618 and 0.607, respectively). There were good correlations between total LUS score and scores from three systems reflecting disease severity (R=0.394-0.660, p<0.01).

CONCLUSION

In conclusion, interobserver agreement for different signs and total scores in LUS is good and justifies its use in patients with COVID-19. The total scores of LUS are useful to indicate disease severity.

Ion irradiation induced strain and structural changes in LiTaO3perovskite

LiTaO₃crystals irradiated with 3 MeV and 1.162 GeV Au ions were studied by single crystal x-ray diffraction and Raman scattering measurements. The maximum lattice strains after 3 MeV Au ion irradiation to a fluence of 1.2 × 10¹³ cm^-2were 1.2% and 0.6% along thec- anda-/b-axes, respectively. Two effects were observed in 1.162 GeV Au ion irradiated samples: (i) the (0006) and (1120) Bragg peaks were split into doublets, which suggested a subtle structural change due to slight modification of chemical composition; and (ii) the pre-damaged 1.2% lattice strain along thec-axis was relaxed to 0.9% after subsequent irradiation with 1.162 GeV Au ions, while relaxation along thea- orb-axis was not obvious. A distinct change in the Raman spectrum of the 〈0001〉 oriented LiTaO₃crystals was observed after 1.162 GeV Au ion irradiation, but no obvious change was observed in the 〈1120〉 oriented samples or in 3 MeV Au ion irradiated samples. Strain and structural changes in crystalline LiTaO₃, with or without pre-existing defects, upon ion irradiation are delineated in its responding to inelastic ionization and elastic nuclear collisions.

Impact of obesity on myocardial microvasculature assessed using fully-automated inline myocardial perfusion mapping CMR

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Guy"s and St Thomas" Charity University College London Hospitals Biomedical Research Centre

Background

Obesity and cardiovascular disease are associated, but the relationship is poorly understood. Myocardial perfusion, metabolic derangement and lipotoxicity appear adversely associated in many scenarios (myocardial injury, diastolic dysfunction, diabetes). Altered perfusion (by PET) predicts outcome, and it is hypothesised that perfusion derangement is part of causality for cardiac disease and adverse outcomes.

Purpose

To assess the presence and pattern of myocardial microvascular dysfunction in patients with obesity (scheduled for bariatric surgery) using stress quantitative perfusion mapping.

Methods

38 subjects with obesity planned to undergo bariatric surgery and 38 age and sex matched healthy volunteers (no diabetes, no hypertension) underwent anthropometry, biochemistry and CMR at 1.5T (Siemens) with cine imaging, stress (adenosine 140-210 mcg/kg/min) and rest fully-automated quantitative perfusion mapping. 

Results

Bariatric patients had a higher BMI (44 ± 6.4 vs 26.5 ± 4kg/m2 p = 0.001); 58%(22) were diabetic and 58%(22) had hypertension. Bariatric patients had higher absolute but lower indexed end-diastolic volumes, and overall higher ejection fractions (+5%) (see Table). Rest myocardial blood flow (MBF) in bariatric patients was the same (1.00 ± 0.3 vs 0.88 ± 0.24 p = 0.052), but stress perfusion results were significantly lower both for stress MBF (2.35 ± 0.69 vs 2.93 ± 0.76ml/g/min p = 0.001) and myocardial perfusion reserve (MPR 2.48 ± 0.82 vs 3.4 ± 0.81ml/g/min p = 0.0001).  Although this was transmural, the endocardial stress MBF was particularly negatively affected in the bariatric cohort compared to controls (endocardial MBF 2.16 ± 0.65 vs 2.82 ± 0.73ml/g/min, p = 0.0001 vs epicardial MBF: 2.52 ± 0.76 vs 3.06 ± 0.79 p = 0.003), meaning there was an increased endo-epicardial stress MBF gradient in bariatric patients (0.87 ± 0.12 vs 0.92 ± 0.07 p = 0.03).

Conclusion

Compared to healthy controls, patients with obesity have abnormal myocardial stress perfusion with reduced global perfusion, perfusion reserve and an increased transmyocardial perfusion gradient.

Table - myocardial perfusion parameters Category Bariatric patients n = 38 Controls n = 38 p value Age (years) 48 ± 11 45 ± 13 0.25 n male (%) 12 (32%) 10 (36%) 0.32 LVEDV (ml) 168 ± 37 149 ± 31 0.017 LVEDVi (ml/m2) 70.4 ± 12.3 78.8 ± 12.1 0.004 LV Mass (g) 116 ± 31 99 ± 28 0.019 EF (%) 70 ± 8 65 ± 5 0.002 LVEDV - left ventricular end-diastolic volume, EF - ejection fraction

Use of quantitative myocardial perfusion mapping by CMR for characterisation of ischaemia in patients post coronary artery bypass graft surgery

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation

Background

Quantitative myocardial perfusion mapping using Cardiac Magnetic Resonance (CMR) imaging is used for evaluation of ischaemia in the context of native vessel coronary disease, but its diagnostic performance in patients with grafts is not well established. Perfusion defects are often detected in these patients, but whether these are a consequence of a technical limitation (delayed contrast arrival from graft conduits) or a true reflection of reduced myocardial blood flow is unclear.

Methods

39 patients undergoing stress perfusion CMR with previous coronary artery bypass graft (CABG) surgery, unobstructed left internal mammary artery (LIMA) grafts to the left anterior descending (LAD) artery on coronary angiography and no CMR evidence of prior LAD infarction were included. Myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) were evaluated with quantitative perfusion mapping and the factors determining MBF in the LIMA-LAD territory (AHA segments 1,2,7,8,13,14), including the impact of delayed contrast arrival through the LIMA graft were evaluated.

Results

In 28 out of 39 cases a myocardial perfusion defect was reported on visual assessment in LIMA-LAD myocardial territory, despite the presence of unobstructed LIMA graft and no LAD infarction. Chronic total occlusion (CTO) of the native LAD was an independent predictor of stress MBF (B=-0.36, p =0.027) and the strongest predictor of MPR (B=-0.55, p 0.005) within the LIMA-LAD myocardial territory after adjusting for age, left ventricular (LV) ejection fraction, and presence of diabetes. CTO of the native LAD was associated with a reduction in stress MBF in the basal myocardial segments (-0.57ml/g/min, p = 0.002) but had no effect on the MBF of apical segments (-0.31ml/g/min, p = 0.084). Increasing the maximum value for allowable arterial delay (TA) of contrast in the quantitative mapping algorithm resulted in a small increase in myocardial blood flow in the LIMA-LAD territory both at stress (0.07 ± 0.08ml/g/min, p &lt; 0.001) and rest (0.06 ± 0.05ml/g/min, p &lt; 0.001).

Conclusions

Perfusion defects detected in LIMA-LAD subtended territories are common despite graft patency. These defects are likely to represent genuine reduction in MBF, resulting from native LAD coronary occlusion. Prolonged contrast transit time associated with LIMA grafts results in small underestimation of MBF as measured by quantitative CMR perfusion mapping, but does not account for the degree of MBF reduction seen in these patients.

Figure 1. Study patient with unobstructed LIMA to LAD graft and evidence of inducible perfusion defect in LIMA-LAD territories. (A): First pass perfusion CMR imaging. (B): Perfusion mapping showing reduced stress MBF in mid antero-septum (0.85ml/g/min) compared to the apical septum (1.65ml/g/min). (C): Late gadolinium enhancement showing no evidence of previous infarction. (D,E): Coronary angiography demonstrating unobstructed LIMA graft (D) and anastomosis site (E).

Abstract Figure 1.

Influences on myocardial perfusion in non-obstructive coronary disease: an observational quantitative perfusion mapping study

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This study was supported by a Clinical Training Research Fellowship (K. Knott) from the British Heart Foundation and directly and indirectly from the Biomedical Research Centre at University College London Hospitals and Barts Heart Centre.

Background

Cardiovascular magnetic resonance (CMR) with automated inline perfusion mapping permits rapid fully automated non-invasive myocardial blood flow (MBF, ml/g/min). Understanding the microvascular component of MBF would help optimize epicardial coronary artery disease detection and potentially serve as an independent diagnostic / therapeutic target. 

Purpose

To explore MBF influences at stress and rest in patients with unobstructed epicardial coronary arteries.

Methods

242 participants (mean age 56.9 years) from 5 European centers with unobstructed epicardial coronary arteries and no myocardial scar underwent adenosine vasodilator perfusion mapping at stress and rest. The factors influencing MBF were determined using univariate and multivariate linear regression analyses.

Results

Mean rest perfusion was 0.91+/-0.24ml/g/min. Rest perfusion was higher in females (0.97+/-0.22ml/g/min vs 0.83 +/- 0.24ml/g/min) and lower in patients on beta blockers. Mean stress MBF was 2.53+/-0.82ml/g/min. Factors independently associated with reduced stress MBF were increasing age, diabetes, increasing left ventricular mass (LVMi) and the use of beta blockers.  The predicted stress MBF can be obtained from the equation MBF = 2.66–0.015(age-60)–0.013(LVMi-57)-0.405(diabetes)–0.365(beta blocker). This means stress MBF falls 10% over 19 years and that diabetes drops the MBF by the equivalent of being 27 years older. These changes are large: for example, a 70-year-old diabetic would have 30% lower stress MBF than a 35 year-old non-diabetic. 

Conclusions

In the absence of obstructive epicardial coronary disease, stress MBF falls with age, diabetes, increased LV mass and beta-blockers. These data may help develop normal reference ranges, input to other modelling (eg CT FFR), and they advance perfusion mapping as a measure of microvascular function.

Abstract Figure. Summary of the determinants of perfusion

Uric Acid Variability and All-Cause Mortality: A Prospective Cohort Study in Northern China

OBJECTIVES

Uric acid(UA) is related with cardiovascular disease, but the association of UA variability with all-cause mortality is rarely known. This study aimed to investigate the relationship between UA variability and all-cause mortality in Kailuan cohort study in northern China.

DESIGN

Cohort study.

SETTING

Kailuan community hospitals in Tangshan, Hebei province, Northern China.

PARTICIPANTS

A total of 55717 participants from Kailuan Study were enrolled, and our study followed up biennially from 2006 to 2010.

MEASUREMENTS

Clinical records of the participants enrolled were analyzed. UA variation independent of mean (UAVIM) values were calculated and all the participants were quartile grouped into four groups as: Q1(UAVIM<0.68), Q2(0.68≤UAVIM<1.10), Q3(1.10≤UAVIM<1.67) and Q4(UAVIM≥1.67). The endpoint event was all-cause death. Cox regression model was performed to evaluate the hazard ratios(HRs) of all-cause mortality based on UAVIM groups.

RESULTS

During a median follow-up of 6.83 years, 2926 deaths occurred. The accumulated mortality rates were 4.6%, 4.8%, 5.4% and 6.1% in group Q1, Q2, Q3 and Q4 respectively. When adjusted potential confounders, the highest risk for all-cause mortality was in group Q4 and the adjusted HRs and 95% confidence intervals(CIs) of group Q2-Q4 for all-cause death were 1.044(0.937, 1.164), 1.182(1.064, 1.314) and 1.353(1.220, 1.501) compared with group Q1, respectively. Further analysis showed that the risk for all-cause death increased as UAVIM value increased. Sensitive analysis still showed the similar results when excluding participants with hyperuricemia or severe chronic kidney diseases. Sub-group analysis by age, gender, BMI or hypertension history also indicated analogous results.

CONCLUSION

Elevated UAVIM was related with increased all-cause mortality and UAVIM was an independent risk factor for all-cause mortality in the community cohort study.

[A qualitative study on HIV related risk behaviors, current status and need for prevention services among 28 money boys]

Objective: To understand the characteristics of HIV-related risk behaviors and needs for prevention services among males who sell sex for money or anything of value (commonly known as money boys or MB), and to provide evidence for the development of targeted interventions. Methods: Using non-probability purposive sampling method and one-on-one interviews. Results: A total of 28 MBs were interviewed, with age range between 20 and 67, and education primarily at junior high school level. Among them 6 were married. Their household registration for residency cut across 15 provinces, and their sexual orientation is diverse. They migrate primarily among tier one cities and provincial capitals. Most enter the trade for economic reasons, relying on clubs and personal networks to find clients, and on word of mouth to obtain knowledge and skills. In addition to their primary clientele of the male homosexual community, 5 out of 28 serve male heterosexuals and 6 out of 28 also serve females. They have some awareness of self protection from diseases, primarily from word of mouth. Nevertheless, over half of them cannot maintain consistent condom use, and 12 out of 28 have a history of illegal drug use. Three of them reported being tested positive for HIV, and all continue to engage in sex work. They prefer their communication messages to be simple and straight-forward. Privacy comes first when they are accessing testing and treatment services. Conclusion: The bridge role of the MB community in transmitting HIV to the general population cannot be ignored, and interventions targeting the MB population need to be strengthened.

LncRNA HOTAIR regulates the proliferation and apoptosis of vascular smooth muscle cells through targeting miRNA-130b-3p/PPARα axis

OBJECTIVE

To investigate the role of long non-coding RNA (lncRNA) HOTAIR in influencing the proliferative and apoptotic abilities of vascular smooth muscle cells (VSMCs) by regulating microRNA-130b-3p (miRNA-130b-3p)/peroxisome proliferator-activated receptor alpha (PPARα) axis.

MATERIALS AND METHODS

The expression levels of HOTAIR, miRNA-130b-3p, and PPARα in VSMCs treated with different doses of ox-LDL for different time points were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The subcellular distribution of HOTAIR in VSMCs was examined. The regulatory effects of HOTAIR, miRNA-130b-3p, and PPARα on the viability and apoptosis of ox-LDL-treated with VSMCs were assessed. The interaction among HOTAIR, miRNA-130b-3p, and PPARα was evaluated through Dual-luciferase reporter gene assay and Western blot.

RESULTS

After treatment of different doses of ox-LDL in VSMCs, the levels of HOTAIR and PPARα were gradually downregulated, whereas miRNA-130b-3p was upregulated. The overexpression of HOTAIR reversed the enhanced viability and suppressed apoptosis in ox-LDL-treated VSMCs. HOTAIR was mainly distributed in nucleus of VSMCs. MiRNA-130b-3p was the direct target of HOTAIR and its level was negatively regulated by HOTAIR. Moreover, miRNA-130b-3p could bind to PPARα and could negatively regulate its level. The knockdown of HOTAIR could reverse the regulatory effect of PPARα on the proliferative and apoptotic abilities of VSMCs CONCLUSIONS: HOTAIR reduces the proliferative ability and stimulates the apoptosis in ox-LDL-treated VSMCs by targeting miRNA-130b-3p/PPARα axis.

Diffusion tensor cardiovascular magnetic resonance predicts adverse remodelling after myocardial infarction

Background

Changes in myocardial microstructure that underlie post-myocardial infarction (MI) left ventricular (LV) remodelling may contribute to progressive deterioration in cardiac function and increased risk of adverse clinical events. Diffusion Tensor Cardiovascular Magnetic Resonance (DT-CMR) derived parameters provide in vivo measures of helix angle (HA) and sheetlet angle (SA), which allow non-invasive characterization of microstructural dynamics associated with cardiac contraction.

Purpose

To evaluate the relationship between DT-CMR metrics of myocardial microstructure with the development of adverse LV remodelling and to determine the relationship between DT-CMR and strain post- MI.

Methods

We performed a longitudinal pre-clinical CMR study whereby DT-CMR, cine imaging and strain were acquired pre-MI and 3 days and 16 weeks post- MI in a pig model. HA (E1A), SA (E2A), and sheetlet angle mobility (ΔE2A = E2Asystole– E2Adiastole), as well as circumferential (Ecc) and radial (Err) strain were calculated at each timepoint and related to change in left ventricular end-diastolic volume (ΔLVEDV) and change in left ventricular end-systolic volume (ΔLVESV) between 3 days post-MI and 16 weeks post-MI. The translational value of this preclinical study was further assessed in six patients with chronic MI.

Results

ΔE2A over the whole LV (global ΔE2A) at 3 days post-MI correlated significantly with ΔLVEDV (R2=0.89, p=0.0013, Fig.1A;) and ΔLVESV (R2=0.81, p=0.0055, Fig.1B). Global Ecc at 3 days post-MI also correlated with both ΔLVEDV (R2=0.75, p=0.012, Fig.1C) and ΔLVESV (R2=0.71, p=0.018, Fig.1D). Global Err at 3 days post-MI did not show significant correlation with either ΔLVEDV (R2=0.32, p=0.19, Fig.1E) or ΔLVESV (R2=0.35, p=0.17, Fig.1F). Global ΔE2A correlated strongly with global Ecc 3 days post-MI (R2=0.9, p=0.00099, Fig.1G) but less strongly with global Err 3 days post-MI (R2=0.57, p=0.049, Fig.1H). Global ΔE2A at the chronic stage correlated significantly with ejection Fraction (EF), in both clinical (R2=0.87, p=0.007) and preclinical data (R2=0.87, p=0.0024). Global ΔE2A correlated well with LVEDV (clinical: R2=0.72, p=0.033; preclinical: R2=0.8, p=0.0066) and LVESV (clinical: R2=0.78, p=0.020; preclinical: R2=0.89, p=0.0013). In vivo E1A maps at 16 weeks post-MI and ex vivo DT-CMR demonstrated reduced right-handed helix angles in the endocardium of the infarct region.

Conclusion

ΔE2A measured at 3 day post-reperfused MI is strongly correlated with the development of increased end-systolic and end-diastolic volumes, and may therefore serve as a novel CMR early predictor of adverse LV remodelling after reperfused MI. Strong correlations between ΔE2A, LV volumes and EF in a small cohort of stable patients with remodelled hearts after chronic MI confirm the feasibility of performing these measurements in patients and the plausibility of further evaluation of ΔE2A as a predictor of adverse remodelling after reperfused MI.

Sheetlet mobility predicts volume change

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Institutes of Health by the Division of Intramural Research (NHLBI, NIH, DHHS); British Heart Foundation

CHANGES OF WNT/B-CATENIN SIGNALING AND DIFFERENTIATION POTENTIAL OF BONE MARROW MESENCHYMAL STEM CELLS IN PROCESS OF BONE LOSS IN OVARIECTOMIZED RATS

Background

In vitro studies of the changes about osteoblastogenesis and adipogenesis potential of BMSCs were not clear. As it is the critical pathway for osteogenic differentiation and bone formation, whether or not Wnt/β-catenin signalling is involved in the changes of osteogenic and adipogenic potential of BMSCs and participates in bone content decrease of ovariectomized (OVX)osteoporosis rats has been rarely reported.

Material/Methods

BMSCs from femurs of ovariectomzed rats were isolated and cultured in vitro. The proliferation potential of BMSCs was analysed by CCK-8 assays . Osteoblastic and adipogenic differentiation potential of the BMSCs was assessed by ALP activity assay, Alizarin red S staining, Oil red O staining and RT-PCR analysis.

Results

The results demonstrated that BMSCs from bilateral ovariectomization rats were endowed with lower proliferation and osteoblastic differentiation potential but higher adipogenic potential than the control group in vitro. In addition, β-catenin was found to have been decreased in OVX BMSCs, indicating that Wnt/β-catenin signalling pathways were suppressed in OVX BMSCs .

Conclusions

Results suggested that changes in the Wnt canonical signalling pathway may be related to imbalances of osteogenic and adipogenic potential of BMSCs, and this may be an important factor related to bone content decrease in ovariectomized osteoporosis rats.