The longitudinal behavioral effects of acute exposure to galactic cosmic radiation in female C57BL/6J mice: implications for deep space missions, female crews, and potential antioxidant countermeasures

Galactic cosmic radiation (GCR) is an unavoidable risk to astronauts that may affect mission success. Male rodents exposed to 33-beam-GCR (33-GCR) show short-term cognitive deficits but reports on female rodents and long-term assessment is lacking. Here we asked: What are the longitudinal behavioral effects of 33-GCR on female mice? Also, can an antioxidant/anti-inflammatory compound mitigate the impact of 33-GCR? Mature (6-month-old) C57BL/6J female mice received the antioxidant CDDO-EA (400 µg/g of food) or a control diet (vehicle, Veh) for 5 days and either Sham-irradiation (IRR) or whole-body 33-GCR (0.75Gy) on the 4th day. Three-months post-IRR, mice underwent two touchscreen-platform tests: 1) location discrimination reversal (which tests behavior pattern separation and cognitive flexibility, two abilities reliant on the dentate gyrus) and 2) stimulus-response learning/extinction. Mice then underwent arena-based behavior tests (e.g. open field, 3-chamber social interaction). At the experiment end (14.25-month post-IRR), neurogenesis was assessed (doublecortin-immunoreactive [DCX+] dentate gyrus neurons). Female mice exposed to Veh/Sham vs. Veh/33-GCR had similar pattern separation (% correct to 1st reversal). There were two effects of diet: CDDO-EA/Sham and CDDO-EA/33-GCR mice had better pattern separation vs. their respective control groups (Veh/Sham, Veh/33-GCR), and CDDO-EA/33-GCR mice had better cognitive flexibility (reversal number) vs. Veh/33-GCR mice. Notably, one radiation effect/CDDO-EA countereffect also emerged: Veh/33-GCR mice had worse stimulus-response learning (days to completion) vs. all other groups, including CDDO-EA/33-GCR mice. In general, all mice show normal anxiety-like behavior, exploration, and habituation to novel environments. There was also a change in neurogenesis: Veh/33-GCR mice had fewer DCX+ dentate gyrus immature neurons vs. Veh/Sham mice. Our study implies space radiation is a risk to a female crew's longitudinal mission-relevant cognitive processes and CDDO-EA is a potential dietary countermeasure for space-radiation CNS risks.

Membrane phospholipid remodeling modulates nonalcoholic steatohepatitis progression by regulating mitochondrial homeostasis

BACKGROUND AND AIMS

NASH, characterized by inflammation and fibrosis, is emerging as a leading etiology of HCC. Lipidomics analyses in the liver have shown that the levels of polyunsaturated phosphatidylcholine (PC) are decreased in patients with NASH, but the roles of membrane PC composition in the pathogenesis of NASH have not been investigated. Lysophosphatidylcholine acyltransferase 3 (LPCAT3), a phospholipid (PL) remodeling enzyme that produces polyunsaturated PLs, is a major determinant of membrane PC content in the liver.

APPROACH AND RESULTS

The expression of LPCAT3 and the correlation between its expression and NASH severity were analyzed in human patient samples. We examined the effect of Lpcat3 deficiency on NASH progression using Lpcat3 liver-specific knockout (LKO) mice. RNA sequencing, lipidomics, and metabolomics were performed in liver samples. Primary hepatocytes and hepatic cell lines were used for in vitro analyses. We showed that LPCAT3 was dramatically suppressed in human NASH livers, and its expression was inversely correlated with NAFLD activity score and fibrosis stage. Loss of Lpcat3 in mouse liver promotes both spontaneous and diet-induced NASH/HCC. Mechanistically, Lpcat3 deficiency enhances reactive oxygen species production due to impaired mitochondrial homeostasis. Loss of Lpcat3 increases inner mitochondrial membrane PL saturation and elevates stress-induced autophagy, resulting in reduced mitochondrial content and increased fragmentation. Furthermore, overexpression of Lpcat3 in the liver ameliorates inflammation and fibrosis of NASH.

CONCLUSIONS

These results demonstrate that membrane PL composition modulates the progression of NASH and that manipulating LPCAT3 expression could be an effective therapeutic for NASH.

Clinical characteristics, outcomes and risk factors for mortality in hospitalized diabetes and chronic kidney disease patients after COVID-19 infection following widespread vaccination

BACKGROUND

COVID-19 poses a significant threat to patients with comorbidities, such as diabetes and chronic kidney disease (CKD). China experienced a nationwide COVID-19 endemic from December 2022 to January 2023, which is the first occurrence of such an outbreak following China's widespread administration of COVID-19 vaccinations.

METHODS

A total of 338 patients with diabetes and CKD combined with COVID-19 infection between December 7, 2022 and January 31, 2023 were included in this study. The end follow-up date was February 10, 2023. Univariate analysis and multivariate Cox analysis were used to analyze risk factors for death.

RESULTS

During the 50-day median follow-up period, 90 patients in the study cohort died, for a mortality rate of 26.63%. The median age of the study cohort was 74 years, with a male predominance of 74%. During hospitalization, 21% of patients had incident AKI, 17% of patients experienced stroke, and 40% of patients experienced respiratory failure. Cox proportional hazard regression showed that older age, a diagnosis of severe or critically severe COVID-19 infection, incident AKI and respiratory failure, higher level of average values of fasting glucose during hospitalization, UA, and total bilirubin were independent risk factors for death in our multivariate model.

CONCLUSIONS

These findings highlight the critical importance of identifying and managing comorbid risk factors for COVID-19, especially among the elderly, in order to optimize clinical outcomes, even after COVID-19 vaccination.

Nutrient metabolism in regulating intestinal stem cell homeostasis

Intestinal stem cells (ISCs) are known for their remarkable proliferative capacity, making them one of the most active cell populations in the body. However, a high turnover rate of intestinal epithelium raises the likelihood of dysregulated homeostasis, which is known to cause various diseases, including cancer. Maintaining precise control over the homeostasis of ISCs is crucial to preserve the intestinal epithelium's integrity during homeostasis or stressed conditions. Recent research has indicated that nutrients and metabolic pathways can extensively modulate the fate of ISCs. This review will explore recent findings concerning the influence of various nutrients, including lipids, carbohydrates, and vitamin D, on the delicate balance between ISC proliferation and differentiation.

Targeting phospholipid remodeling pathway improves insulin resistance in diabetic mouse models

Previous studies have revealed that membrane phospholipid composition controlled by lysophosphatidylcholine acyltransferase 3 (LPCAT3) is involved in the development of insulin resistance in type 2 diabetes. In this study, we aimed to investigate the therapeutic potential of targeting Lpcat3 in the treatment of insulin resistance in diabetic mouse models. Lpcat3 expression was suppressed in the whole body by antisense oligonucleotides (ASO) injection or in the liver by adeno-associated virus (AAV)-encoded Cre in high-fat diet (HFD)-induced and genetic ob/ob type 2 diabetic mouse models. Glucose tolerance test (GTT), insulin tolerance test (ITT), fasting blood glucose, and insulin levels were used to assess insulin sensitivity. Lipid levels in the liver and serum were measured. The expression of genes involved in de novo lipogenesis was analyzed by real-time RT-PCR. Metabolic rates were measured by indirect calorimetry using the Comprehensive Lab Animal Monitoring System (CLAMS). Our data demonstrate that acute knockout of hepatic Lpcat3 by AAV-Cre improves both hyperglycemia and hypertriglyceridemia in HFD-fed mice. Similarly, whole-body ablation of Lpcat3 by ASO administration improves obesity and insulin resistance in both HFD-fed and ob/ob mice. These findings demonstrate that targeting LPCAT3 could be a novel therapy for insulin resistance.

Concurrent Chemoradiotherapy plus Programmed Death-1 (PD-1) Blockade for Locally Advanced Cervical Cancer: Preliminary Results of a Single-Arm, Open-Label, Phase II Trial

PURPOSE/OBJECTIVE(S)

This study aims to assess the anti-tumor activity and safety of concurrent chemoradiotherapy plus PD-1 blockade in patients with locally advanced cervical cancer.

MATERIALS/METHODS

This is a single-arm, open-label, prospective phase II study. The key inclusion criteria were treatment-naive patients aged 18-75 years with stage II A2-IVA (FIGO 2018) locally advanced cervical cancer. All patients were treated with concurrent chemoradiotherapy including 2 cycle cisplatin (75mg/m2, for three days, every 3 weeks[Q3W]), nedaplatin or carboplatin can be selected for patients who can't tolerate cisplatin. After CCRT, patients achieving complete response (CR), partial responses(PR), stable disease(SD) received adjuvant chemotherapy (docetaxel 75 mg/m2 day 1+ cisplatin DDP 25 mg/m2 day 1-3, Q3W) for 2 cycle. PD-1 blockade Sintilimab and Tislelizumab was administered intravenously at 200 mg every 3 weeks up to 1 year or until disease progression, unacceptable toxicity, or withdrawal of consent. The primary endpoint was objective response rate (ORR) assessed by investigators per Response Evaluation Criteria In Solid Tumours (RECIST) version 1.1. Secondary endpoints were the 12, 24-month overall survival (OS) rates, the 12, 24-month disease free survival (DFS) rates and safety.

RESULTS

From February 2020 to June 2022, a total of 15 patients was enrolled. Median age was 57 years (range, 36-74 years). Stage IIA1 was documented in 2 patients, stage IIA2 in two patients, stage IIIA in one patient, stage IIIC1 in eight patients, and stage IVA in two patients. And 66.7% (10/15) of patients had Metastatic lymph node. Four patients received adjuvant chemotherapy. The ORR was 100%, with 4 patients achieving CR and 11 PR. The 12 and 24-month OS rates are 93.3% and 84%, the 12 and 24-month DFS rates are 86% and 75.4%, respectively. Treatment-related adverse events (TRAEs) occurred in 86.7% (13/15) of patients. Grade 3 TRAEs are leukocyte (n = 1), thrombocytopenia (n = 1), hepatitis (n = 1), skin reaction (n = 1). No treatment-related deaths occurred. And IFN-γ was significantly elevated after radiotherapy (p = 0.0073).

CONCLUSION

Concurrent chemoradiotherapy plus PD-1 blockade showed promising antitumor activity and manageable toxicities in patients with locally advanced cervical cancer. Long-term outcomes are still pending to further evaluate their therapeutic effects. (ChiCTR2000032856).

Hepatic Phospholipid Remodeling Modulates Insulin Sensitivity and Systemic Metabolism

The liver plays a central role in regulating glucose and lipid metabolism. Aberrant insulin action in the liver is a major driver of selective insulin resistance, in which insulin fails to suppress glucose production but continues to activate lipogenesis in the liver, resulting in hyperglycemia and hypertriglyceridemia. The underlying mechanisms of selective insulin resistance are not fully understood. Here It is shown that hepatic membrane phospholipid composition controlled by lysophosphatidylcholine acyltransferase 3 (LPCAT3) regulates insulin signaling and systemic glucose and lipid metabolism. Hyperinsulinemia induced by high-fat diet (HFD) feeding augments hepatic Lpcat3 expression and membrane unsaturation. Loss of Lpcat3 in the liver improves insulin resistance and blunts lipogenesis in both HFD-fed and genetic ob/ob mouse models. Mechanistically, Lpcat3 deficiency directly facilitates insulin receptor endocytosis, signal transduction, and hepatic glucose production suppression and indirectly enhances fibroblast growth factor 21 (FGF21) secretion, energy expenditure, and glucose uptake in adipose tissue. These findings identify hepatic LPCAT3 and membrane phospholipid composition as a novel regulator of insulin sensitivity and provide insights into the pathogenesis of selective insulin resistance.

Intestinal SEC16B modulates obesity by regulating chylomicron metabolism

OBJECTIVE

Genome-wide association studies (GWAS) have identified genetic variants in SEC16 homolog B (SEC16B) locus to be associated with obesity and body mass index (BMI) in various populations. SEC16B encodes a scaffold protein located at endoplasmic reticulum (ER) exit sites that is implicated to participate in the trafficking of COPII vesicles in mammalian cells. However, the function of SEC16B in vivo, especially in lipid metabolism, has not been investigated.

METHODS

We generated Sec16b intestinal knockout (IKO) mice and assessed the impact of its deficiency on high-fat diet (HFD) induced obesity and lipid absorption in both male and female mice. We examined lipid absorption in vivo by acute oil challenge and fasting/HFD refeeding. Biochemical analyses and imaging studies were performed to understand the underlying mechanisms.

RESULTS

Our results showed that Sec16b intestinal knockout (IKO) mice, especially female mice, were protected from HFD-induced obesity. Loss of Sec16b in intestine dramatically reduced postprandial serum triglyceride output upon intragastric lipid load or during overnight fasting and HFD refeeding. Further studies showed that intestinal Sec16b deficiency impaired apoB lipidation and chylomicron secretion.

CONCLUSIONS

Our studies demonstrated that intestinal SEC16B is required for dietary lipid absorption in mice. These results revealed that SEC16B plays important roles in chylomicron metabolism, which may shed light on the association between variants in SEC16B and obesity in human.

[Influence of reactive oxygen species responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats]

Objective: To investigate the influence of reactive oxygen species (ROS) responsive self-assembled nanomicelle loaded with pyroptosis inhibitor on full-thickness skin defects in diabetic rats. Methods: Experimental research methods were employed. A nucleotide-binding oligomerization domain (NOD) 1/2 inhibitor (NOD-IN-1) was encapsulated with nanomicelle polyethylene glycol-block-polypropylene sulfide (PEG-b-PPS), and the resulting product was called PEPS@NOD-IN-1. The morphology and hydration particle size of PEG-b-PPS and PEPS@NOD-IN-1 were observed by transmission electron microscope and particle size analyzer, respectively, and the encapsulation rate and drug loading rate of PEPS@NOD-IN-1 to NOD-IN-1 and the cumulative release rate of NOD-IN-1 by PEPS@NOD-IN-1 in phosphate buffer solution (PBS) alone and hydrogen peroxide-containing PBS within 40 h were measured and calculated by microplate reader, and the sample number was 3. Twenty-four male Sprague-Dawley rats aged 6-7 weeks were injected with streptozotocin to induce type 1 diabetes mellitus. Six full-thickness skin defect wounds were made on the back of each rat. The injured rats were divided into PBS group, NOD-IN-1 group, PEG-b-PPS group, and PEPS@NOD-IN-1 group with corresponding treatment according to the random number table, with 6 rats in each group. The wound healing was observed on post injury day (PID) 3, 7, and 12, and the wound healing rate was calculated. The ROS levels in wound tissue were detected by immunofluorescence method on PID 3. On PID 7, the granulation tissue thickness in wound was assessed by hematoxylin-eosin staining, the mRNA expressions of NOD1 and NOD2 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction, and the protein expressions of NOD1, NOD2, and GSDMD-N terminals were detected by Western blotting. Six wounds from different rats in each group were taken for detection of the above indicators. Wound tissue (3 samples per group) was taken from rats in PBS group and PEPS@NOD-IN-1 group on PID 7, and transcriptome sequencing was performed using high-throughput sequencing technology platform. Differentially expressed genes (DEGs) significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were screened, and the enrichment analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed. The DEG heatmap of the NOD-like receptor pathway, a pyroptosis-related pathway, was made. Protein-protein interaction (PPI) analysis of DEGs in heatmap was performed through the STRING database to screen key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and Tukey test. Results: PEG-b-PPS and PEPS@NOD-IN-1 were in spherical structures of uniform size, with hydration particle sizes of (134.2±3.3) and (143.1±2.3) nm, respectively. The encapsulation rate of PEPS@NOD-IN-1 to NOD-IN-1 was (60±5)%, and the drug loading rate was (15±3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in PBS alone was slow, and the cumulative release rate at 40 h was only (12.4±2.3)%. The release of NOD-IN-1 from PEPS@NOD-IN-1 in hydrogen peroxide-containing PBS within 10 h was very rapid, and the cumulative release rate at 10 h reached (90.1±3.6)%. On PID 3 and 7, the wounds of rats in the four groups were gradually healed, and the healing in PEPS@NOD-IN-1 group was better than that in the other three groups. On PID 12, the wound scab area in PBS group was large, the wound epithelialization in NOD-IN-1 group and PEG-b-PPS group was obvious, and the wound in PEPS@NOD-IN-1 group was close to complete epithelialization. Compared with those in PBS group, NOD-IN-1 group, and PEG-b-PPS group, the wound healing rates on PID 7 and 12 in PEPS@NOD-IN-1 group were significantly increased (P<0.05), the level of ROS in wound tissue on PID 3 was significantly decreased (P<0.05), the thickness of granulation tissue in wound on PID 7 was significantly thickened (P<0.05), and the mRNA expressions of NOD1 and NOD2 and the protein expressions of NOD1, NOD2, and GSDMD-N terminals in wound tissue on PID 7 were significantly decreased (P<0.05). KEGG pathway analysis showed that DEGs significantly down-regulated in PEPS@NOD-IN-1 group as compared with PBS group were significantly enriched in NOD-like receptors, hypoxia-inducible factors, mitogen-activated protein kinases, and tumor necrosis factor (TNF) pathways. In the DEG heatmap of NOD-like receptor pathway, the genes regulating pyroptosis mainly involved NOD1, NOD2, NOD-like receptor thermoprotein domain-related protein 3, Jun, signal transduction and transcriptional activator 1 (STAT1), TNF-α-induced protein 3. The PPI results showed that NOD1, NOD2, and STAT1 were the key genes of PEPS@NOD-IN-1 regulating the NOD-like receptor pathway. Conclusions: PEPS@NOD-IN-1 can down-regulate the level of local ROS in wounds and the expression of NOD1, NOD2, and GSDMD-N terminals, the key regulators of pyroptosis, thereby promoting the repair of full-thickness skin defect wounds in diabetic rats. PEPS@NOD-IN-1 can also significantly down-regulate the pyroptosis, inflammation, and hypoxia-related pathways of wounds, and regulate NOD-like receptor pathways by down-regulating key genes NOD1, NOD2, and STAT1.

Aging-induced down-regulation of Pka/Bkca pathway in rat cerebral arteries

The incidence of cerebrovascular diseases increases significantly with aging. This study aimed to test the hypothesis that aging may influence the protein kinase A (PKA)-dependent vasodilation via RyR/BKCa pathway in the middle cerebral arteries (MCA). Male Sprague-Dawley rats were randomly divided into control (4-6 month-old) and aged (24-month-old) groups. The functions of MCA and ion channel activities in smooth muscle cells were examined using myograph system and patch-clamp. Aging decreased the isoproterenol/forskolin-induced relaxation in the MCA. Large-conductance Ca2+-activated-K+ (BKCa) channel inhibitor, iberiotoxin, significantly attenuated the forskolin-induced vasodilatation and hyperpolarization in the young group, but not in the aged group. The amplitude and frequency of spontaneous transient outward currents (STOCs) were significantly decreased in the aged group. Single channel recording revealed that the mean open time of BKCa channels were decreased, while an increased mean closed time of BKCa channels were found in the aged group. The Ca2+/voltage sensitivity of the channels was decreased accompanied by reduced BKCa α and β1-subunit, the expression of RyR2, PKA-Cα and PKA-Cβ subunits were also declined in the aged group. Aging induced down-regulation of PKA/BKCa pathway in cerebral artery in rats. The results provides new information on further understanding in cerebrovascular diseases resulted from age-related cerebral vascular dysfunction.

Impact of cardiac resynchronisation therapy in patients with cardiac sarcoidosis

Background

Implantation of a device is usually required in cardiac sarcoidosis (CS) patients presenting with advanced conduction abnormalities or ventricular arrhythmias. A cardiac resynchronisation therapy (CRT) device is often chosen in patients with concomitant left ventricular systolic impairment. The role of CRT in CS is not well established.

Purpose

To describe the cohort of CS patients with CRT device in situ in our hospital focusing on the short-term effect in serial echocardiography and long-term outcomes on morbidity and mortality.

Methods

All consecutive CS patients with a CRT device in situ were identified in our CS database (2005–2022). A confident CS diagnosis was provided after review of all relevant clinical and imaging baseline data in our CS multi-disciplinary meeting and a consensus decision for CRT-D implantation was made based on international guidelines. All patients were followed up for at least 6 months with serial echocardiography. Serial data regarding symptoms, rhythm disturbance and echocardiographic parameters were obtained and comparisons were performed using Wilcoxon signed rank test.

Results

A total of 51 CS patients with CRT-D were identified (mean age: 57±10 years old). Patients were male predominant (64.7%) and Caucasian in origin (86.2%). Extra-cardiac sarcoidosis was confirmed histologically in 33 (64.7%) patients. The prevalence of smoking, diabetes, hypertension and ischaemic heart disease was 27.5%, 21.6%, 49.0% and 7.8% respectively. At the time of device implantation or during follow-up, 43 (84.3%) patients were found to have active cardiac sarcoidosis on cardiac PET.

Post CRT implantation there was a significant difference in LV ejection fraction (35.9±15.0% vs 42.2±14.1%, p&lt;0.001), LV end-systolic diameter (4.90±1.46 cm vs 4.62±1.32 cm, p=0.012) and LV end-diastolic diameter (5.99±1.18 cm vs 5.66±1.06 cm, p&lt;0.001). No significant changes were observed in the right ventricular function (p=0.09) and severity of mitral regurgitation (p=0.40). There was one patient who experienced acute heart failure decompensation admission within six months of CRT-D implantation. The New York Heart Association (NYHA) class improved in 26 patients (51.0%), worsened in 4 (7.8%) patients and remained the same in 21 (41.2%) patients at 6 months post CRT-implantation. During the mean follow up of 47.6 months, the composite end-point of death and cardiac transplantation was reached in 9 (17.6%) patients (8 deaths and 1 cardiac transplantation). 5 patients had major complications including a large haematoma, a small atrio-septal defect, haemothorax, device associated endocarditis and lead fracture. Minor wound infections were seen in 3 patients and 4 patients received inappropriate shock or anti-tachycardia pacing.

Conclusions

CRT in cardiac sarcoidosis patients is associated with short-term improvement in LV remodelling and functional status but over a four year follow up, morbidity and mortality are common.

Funding Acknowledgement

Type of funding sources: None.

Novel biomarkers predict ablation outcomes in long stranding persistent atrial fibrillation

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): NIHR

Background

Ablation of long-standing persistent atrial fibrillation (LSPAF) is not always successful. The arrhythmia burden was reduced by 75% by 12 months in majority (72%) of patients with LSPAF who underwent surgical or percutaneous ablation in the CASA-AF trial. We hypothesised that biomarker(s) improve prediction of clinical success and offer insights into mechanisms.

Objective

To identify biomarkers that predict success (75% arrhythmia burden reduction) after ablation for LSPAF at 12-months.

Methods

Amongst patients participating in the CASA-AF RCT (ISRCTN18250790), pre-ablation serum samples were selected for 20 patients who met criteria for ablation-success at 12 months, and 20 who did not. Olink ProteomicsTM (Sweden) provided analyses using three biomarker panels [inflammation (INFL), cardiovascular III (CVD III), and cell cytology (CELL)] each containing 92 biomarkers. Univariate and multivariable analyses were adjusted for age, sex, BMI, LA diameter and CRP. ROC analysis was undertaken to assess the diagnostic accuracy of the biomarkers. To counter the false discovery rate, Benjamini-Hochberg correction was utilised.

Results

When patients with ablation-success and -failure were compared, no differences in demographics or cardiac function were found. On univariate analysis, several biomarkers in each panel were associated with ablation-success. Multivariable analysis narrowed the range of biomarkers and identified those that were jointly predictive of outcome: INFL (MCP1 + CD8A + CD40, Figure 1), CVD III (FAS + CPB1) and CELL (GCG + ENTPD6 + IL17RB). These joint biomarkers were analysed using ROC (Figure 2), which showed that increases of biomarkers on the INFL panel (MCP1 + CD8A + CD40) were associated with a greater risk of failure and achieved the highest AUC for prediction of outcome [0.82 (0.75-0.87)].

Conclusion

The increase in the serum concentration of markers of inflammation (MCP1 + CD8A + CD40) might be used to identify patients less likely to have sustained benefit from LSPAF ablation. Further studies are required to confirm their prognostic value as pre-procedural biomarkers.

Conduction system pacing in the adult congenital population; feasibility and outcomes

Funding Acknowledgements

Type of funding sources: None.

Background

Left bundle pacing (LBP) is an evolving pacing method designed to capture the intrinsic conduction and minimise ventricular dys- synchrony. Anatomical complexity, scars of previous corrective surgeries and haemodynamic properties of adult congenital heart disease (ACHD) population could increase challenges of LBP. We describe our experience in LBP in ACHD patients and different patient groups.

Purpose

To compare the feasibility of LBP in ACHD patient population and non-ACHD patients.

Methods

We included all patients who had LBP at our institution in 2020 and 2021. Demographic data, imaging data, procedural parameters and follow up data were collected and analysed.

Results

A total of 36 patients were included and divided into two groups: ACHD (n=8, mean age, 54 years, 38% females) and non-ACHD (n=28, mean age, 74 years, 43% females). ACHD anatomy included simple lesions (4) as atrial and ventricular septal defects, partial anomalous pulmonary venous drainage, bicuspid aortic valve and Shone’s syndrome, moderate (3), as Tetralogy of Fallot with surgical repair, and complex (1), as transposition of great arteries with Mustard repair. Non-ACHD included patients with structurally normal heart, dilated cardiomyopathy, and those who underwent mitral and aortic valve interventions. Mean left ventricular ejection fraction in ACHD group was 59.5%, and 57.5% in non-ACHD. Late gadolinium enhancement in basal septal area was present in 5 patients in ACHD group. Acute success rate, defined as capture of left bundle branch, was 100% in ACHD group, and 88% in non-ACHD. No acute complications were recorded in both groups. Mean pre-procedural QRS duration was longer in ACHD group (170 ms, vs, 120, p=&lt;0.001). Mean reduction in QRS duration in ACHD group was 27 ms, vs, 15, p= 0.856. Mean procedural and fluoroscopy times were similar in both groups (ACHD, 75.5 minutes, vs, 70, p= 0.26, and ACHD, 9 minutes, vs 7.13, respectively, p= 0.46). Pacing parameters at implantation and after 2 months were satisfactory in both groups (Fig 1).

Conclusion

Left bundle pacing is feasible in ACHD population as compared to non-ACHD patients, with low incidence of complications. Procedural and fluoroscopic times were similar in both groups. Pacing parameters were satisfactory and stable over 2 month-follow up.

The acute haemodynamic response with endocardial biventricular pacing: comparing RV paced and LBBB patients

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boston Scientific

Background

A third of patients that receive cardiac resynchronisation (CRT) are non-responders. Predictors of positive response include broader QRS duration, non-ischaemic aetiology and sinus rhythm, but it is still unclear whether lead placement site determines a positive responder.

Purpose

We assessed the acute haemodynamic response of endocardial biventricular pacing in patients with intrinsic left bundle brunch block (LBBB) versus LBBB due to pre-existing right ventricular pacing (RVP).

Methods

Patients who fulfilled standard criteria for CRT implantation but had failed conventional (coronary sinus) left ventricular (LV) lead placement (primary or revision) or were deemed clinical ‘non-responders after &gt; 6 months of conventional CRT were enrolled. The acute haemodynamic response during endocardial biventricular pacing was assessed with a roving LV lead at 9 different locations (basal and mid: septal, anterior, posterior and lateral walls and apex). Acute changes in beat-to-beat systolic blood pressure (SBP) in the left ventricle were recorded and analysed.

Results

We recruited 23 patients across 10 UK centres: 14 intrinsic LBBB and 9 dependent on RVP. Patient characteristics were comparable: age (mean 67 + 10.6 years vs. 62 + 15.4 years), ischaemic (63% vs 50%), QRS (160 + 18ms vs. 190 + 36ms, p =0.07). Of the RVP group 5/9 had septal RV leads (the remainder apically positioned).

There was no difference in the SBP improvement between the groups: change in SBP ranged from -5.25 – 19.91mmHg (median 3mmHg) in RVP patients vs -5.92 – 23.03mmHg (median 3mmHg) for intrinsic LBBB. However, the improvement in SBP was more consistent across the different segments in the patients with RVP (group A), as compared to intrinsic LBBB (group B), where the lateral wall and then non-septal walls provided the greatest haemodynamic improvement.

Figure 1: depicts SBP improvement (in mmHg) during endocardial biventricular pacing in different positions within the LV for patients with RVP (A) vs underlying intrinsic LBBB (B): 9 segment model of the LV: Ant (anterior wall), Lat (lateral wall), Post (posterior wall), Sept (septum). Outer ring represents the four basal LV locations, middle ring the mid LV locations and centre ring the apex. Scale depicts mmHg improvement in SBP.

Conclusion

When implanting an LV lead for patients who are RV pacing dependent any position within the LV provides an acute haemodynamic improvement, compared with those with intrinsic LBBB, where a targeted lateral wall approach is more important. This finding corroborates the key differences in LV activation patterns for induced versus intrinsic LBBB.

The Angular Distribution of Lower Band Chorus Waves Near Plasmaspheric Plumes

Plumes have been identified as an access region for chorus waves to enter the plasmasphere. Here, for the first time, chorus wave properties are parameterized by distance from the plume boundary. Case studies and statistical analysis indicate that the polar wave vector angle, θ _k , of chorus becomes more oblique near the plume edge. Occurrence rates of θ _k > 35° on the plume boundary are approximately double that observed further away from the plume. Whilst the increase in θ _k is apparent on both plume edges, the distribution of θ _k exhibits different behavior between the Eastward and Westward boundaries. In general, the distribution of azimuthal wave vector angles, ϕ _k , is symmetric about the anti-Earthwards direction. However, near the Eastward plume boundary, an Eastwards skew of ϕ _k is reported. This result provides new insight on chorus propagation in the context of the chorus-to-hiss mechanism, and has implications for quantifying wave-particle interactions in the near-plume region.

Genetic analyses of blood β-hydroxybutyrate predicted from milk infrared spectra and its association with longevity and female reproductive traits in Holstein cattle

Ketosis is one of the most prevalent and complex metabolic disorders in high-producing dairy cows and usually detected through analyses of β-hydroxybutyrate (BHB) concentration in blood. Our main objectives were to evaluate genetic parameters for blood BHB predicted based on Fourier-transform mid-infrared spectra from 5 to 305 d in milk, and estimate the genetic relationships of blood BHB with 7 reproduction traits and 6 longevity traits in Holstein cattle. Predicted blood BHB records of 11,609 Holstein cows (after quality control) were collected from 2016 to 2019 and used to derive 4 traits based on parity number, including predicted blood BHB in all parities (BHBp), parity 1 (BHB1), parity 2 (BHB2), and parity 3+ (BHB3). Single- and multitrait repeatability models were used for estimating genetic parameters for the 4 BHB traits. Random regression test-day models implemented via Bayesian inference were used to evaluate the daily genetic feature of BHB variability. In addition, genetic correlations were calculated for the 4 BHB traits with reproduction and longevity traits. The heritability estimates of BHBp, BHB1, BHB2, and BHB3 ranged from 0.100 ± 0.026 (± standard error) to 0.131 ± 0.023. The BHB in parities 1 to 3+ were highly genetically correlated and ranged from 0.788 (BHB1 and BHB2) to 0.911 (BHB1 and BHB3). The daily heritability of BHBp ranged from 0.069 to 0.195, higher for the early and lower for the later lactation periods. A similar trend was observed for BHB1, BHB2, and BHB3. There are low direct genetic correlations between BHBp and selected reproductive performance and longevity traits, which ranged from -0.168 ± 0.019 (BHBp and production life) to 0.157 ± 0.019 (BHBp and age at first calving) for the early lactation stage (5 to 65 d). These direct genetic correlations indicate that cows with higher BHBp (greater likelihood of having ketosis) in blood usually have shorter production life (-0.168 ± 0.019). Cows with higher fertility and postpartum recovery, such as younger age at first calving (0.157 ± 0.019) and shorter interval from calving to first insemination in heifer (0.111 ± 0.006), usually have lower BHB concentration in the blood. Furthermore, the direct genetic correlations change across parity and lactation stage. In general, our results suggest that selection for lower predicted BHB in early lactation could be an efficient strategy for reducing the incidence of ketosis as well as indirectly improving reproductive and longevity performance in Holstein cattle.

Effect of baseline disease severity on achievement of treatment target with apremilast: results from a pooled analysis

BACKGROUND

Treating to absolute treatment targets rather than relative measures such as Psoriasis Area and Severity Index (PASI)-75 is emerging as an important clinical concept included in psoriasis guidelines and clinical practice. Achieving treatment targets is associated with achievement of long-term outcomes.

OBJECTIVE

To evaluate the relationship between psoriasis severity, disease characteristics and achievement of PASI ≤2 with apremilast in a pooled analysis of the phase 3 ESTEEM 1 and 2 (NCT01194219 and NCT01232283), phase 3b LIBERATE (NCT01690299) and phase 4 UNVEIL (NCT02425826) clinical trials.

METHODS

Pooled data from patients with moderate-to-severe plaque psoriasis randomized to apremilast 30 mg BID were analysed by baseline PASI quartiles (Q1: 2.4-13.1; Q2: 13.2-15.9; Q3: 16.0-20.0; Q4: 20.1-57.8). Assessments included PASI, Dermatology Life Quality Index (DLQI), Scalp Physician's Global Assessment (ScPGA; ScPGA ≥1) and target (worst) Nail Psoriasis Severity Index (NAPSI; NAPSI ≥1).

RESULTS

Of 1062 patients, 963 had ScPGA ≥1 and 643 had NAPSI ≥1; 771 patients with baseline and Week 32 PASI assessments were included in analyses of Week 32 PASI target achievement. Rates of PASI ≤2 at Week 32 were greater in lower PASI quartiles (Q1: 43.5%; Q2: 31.2%; Q3: 26.8%; Q4: 18.4%). Most patients achieving PASI ≤2 target (83.6%) achieved DLQI ≤5 at Week 32; 59.3% of patients who did not achieve PASI ≤2 target achieved DLQI ≤5. At Week 32, mean improvements in ScPGA and NAPSI were similar with more moderate vs. more severe disease (ScPGA, range: 1.1-1.4; NAPSI, range: 1.6-2.5). In a subgroup analysis, achievement of PASI ≤2 target was higher in the lowest PASI quartile and with disease duration <5 years.

CONCLUSIONS

Greater achievement of PASI ≤2 was observed in patients with more moderate vs. more severe skin disease. Apremilast may be particularly beneficial in more moderate disease early in the treatment paradigm.

[Effect of body mass index on the assisted reproductive outcome of frozen-thawed embryo transfer in patients with polycystic ovary syndrome]

Objective: To investigate the effect of body mass index (BMI) on clinical pregnancy and neonatal outcomes in patients with polycystic ovary syndrome (PCOS) during frozen-thawed embryo transfer. Methods: A total of 650 patients with PCOS who received routine in vitro fertilization or intracytoplasmic sperm injection treatment for frozen-thawed embryo transfer from June 2014 to June 2019 in Tianjin Central Hospital of Gynecology Obstetrics were retrospectively analyzed. According to BMI, PCOS patients were divided into group A (18.5≤BMI<23 kg/m², n=253), group B (23≤BMI<25 kg/m², n=167), and group C (BMI≥25 kg/m², n=230). The general information, clinical pregnancy outcomes, pregnancy complications, the incidence of macrosomia and low-birth-weight infants were compared in the three groups, and the influencing factors of neonatal birth weight were analyzed. Results: The embryo implantation rate, clinical pregnancy rate, and ongoing pregnancy rate all showed downward trend with the increase of BMI, but the differences were not statistically significant (all P>0.05). The live birth rate in group C [47.0% (108/230)] was significantly lower than those in groups A and B, with statistical significance (χ²=7.43, P=0.024). The late miscarriage rate was higher in group C [9.4% (13/139)] than in groups A and B (χ²=7.66, P=0.022). The birth rates of macrosomia in groups B [22.2% (16/72)] and group C [21.1% (16/76)] were significantly higher than that in group A, and the difference was statistically significant (χ²=14.15, P=0.001). There was no statistically significant difference in the incidence of gestational diabetes between the three groups (χ²=3.81, P=0.149). The incidence of hypertension disorders complicating pregnancy increased with the increase of BMI, and the difference was not statistically significant (P>0.05). Regression analysis showed that macrosomia was significantly associated with maternal pre-pregnancy BMI and gestational weeks, and the risk of macrosomia increased by 15% (95%CI: 3%-28%) for every increase in maternal BMI. Conclusions: The embryo implantation rate, clinical pregnancy rate, and ongoing pregnancy rate of PCOS patients in frozen-thawed embryo transfer cycles show downward trend with the increase of BMI. Obese patients with PCOS have a significant increase in late miscarriage rate and a significant decrease in live birth rate. The incidence of hypertension disorders complicating pregnancy in PCOS patients in the obese group has an increasing trend, and the birth rate of macrosomia has increased significantly. Therefore, it is recommended that obese women with PCOS lose weight scientifically before pregnancy to improve pregnancy and neonatal outcomes.

Genetic parameters of hair cortisol as an indicator of chronic stress under different environments in Holstein cows

Chronic stress is a risk factor for a variety of physiological disorders because of its increased activation of the hypothalamic-pituitary-adrenal (HPA) axis; however, it is difficult to reveal environmental and genetic effects contributing to long-term HPA activity because of the complexity of chronic stress. The hair cortisol concentration (HCC) can be used to reflect the accumulation of HPA axis activity over time. Some studies suggest that the HCC might be associated with the protein concentration (PC) in the hair shaft; however, no studies have revealed a dynamic relationship between them. In the present study, 1,086 hair samples from 418 Holstein cows were collected, and the effects of environmental factors on HCC, PC, and ratio of HCC to PC (HCCP) were studied. Subsequently, regression analysis and curve fitting were used to identify for better-performing indicators of chronic stress. Additionally, univariate and bivariate genetic evaluation were used to estimate the genetic components of cortisol traits and genotype by environment interactions (G × E) under different environmental and physiological states. The results showed that HCC and PC are significantly affected by hair color, sampling year, and season, whereas HCCP is not influenced by hair color. Adjusted PC and HCCP, where confounding effects are excluded, were moderately related with chronic stress indicators. Moderate to high heritabilities were obtained for HCC (0.347 and 0.390 for winter and summer, respectively), PC (0.402 and 0.495 for winter and summer, respectively) and HCCP (0.289 and 0.460 for winter and summer, respectively) when animals in the same season were evaluated. A moderate G × E interaction was detected in this study, as indicated by the low or negative genetic correlation for the same cortisol trait in different environments (e.g. heat stress condition and thermoneutral condition). In conclusion, HCCP is not affected by hair color compared with the other 2 traits; thus, it has potential as an indicator of chronic stress. Hair cortisol traits could monitor stress response process in cattle, as well as provide a better understanding of genetic mechanism for long-term HPA activity.

Differences in hypertension and prehypertension among people living with and without HIV in China: role of HIV infection and antiretroviral therapy

OBJECTIVES

Hypertension is a growing health concern in people living with HIV (PLWH). However, association between HIV infection and hypertension is equivocal.

METHODS

In all, 1472 PLWH and 2944 HIV-negative individuals frequency-matched by age and sex were derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China. Prehypertension was defined as systolic blood pressure (BP) of 120-139 mmHg and/or diastolic blood pressure of 80-89 mmHg.

RESULTS

Despite the fact that prevalence of hypertension was overall lower among PLWH than among HIV-negative people (21.1% vs. 29.1%, P < 0.001), it was similar at ages 18-29 (7.6% vs. 8.5%) and 30-44 years (17.1% vs. 18.5%) but significantly lower in PLWH at ages 45-59 (26.1% vs. 40.7%) and 60-75 years (37.1% vs. 57.3%). Prehypertension prevalence was consistently higher in PLWH across all age groups. In the model adjusting for traditional risk factors, HIV infection was associated with hypertension (adjusted odds ratio [aOR] = 1.27, 95% confidence interval: 1.04-1.55) and prehypertension (aOR = 1.77, 95% CI: 1.51-2.08), and attenuated after additional adjustment for abdominal obesity. Age-stratified analysis showed that these associations of HIV with hypertension were observed at ages 18-29 and 30-44 years and associations with prehypertension were observed at ages 18-29, 30-44 and 45-59 years only. Years since HIV diagnosis and stavudine use were the HIV-specific factors independently associated with hypertension or/and prehypertension.

CONCLUSIONS

HIV infection is independently associated with prehypertension and hypertension especially at younger ages, and this risk may increase as treatment becomes prolonged. Our findings reinforce the urgent necessity for active BP screening and control strategies be adopted for PLWH in China.

[Study on maternal-fetal status of Pb, Cd, As, Hg, Mn and Se elements and transplacental transfer efficiency]

Objective: To understand the levels of Pb, Cd, As, Hg, Mn, and Se in maternal and umbilical cord blood, and to explore the transplacental transfer efficiency (TTE). Methods: From September 2010 to December 2013, a total of 773 pregnant women and their newborns (Laizhou Bay Birth Cohort) were recruited from a second grade hospital in the south bank of Laizhou Bay, Bohai, Shandong Province. According to different detection methods, the six measured elements are classified into three groups including the Hg measurement group (595 mother-newborn pairs), the Pb measurement group (534 mother-newborn pairs), and the Cd, As, Mn and Se measurement group (244 mother-newborn pairs). The demographic characteristics of pregnant women and their newborns were obtained by the questionnaire. The concentrations of elements in maternal and umbilical cord blood were detected and the TTE of each element (elemental concentration in cord blood/elemental concentration in maternal blood) was calculated. The correlation of elements between maternal and cord blood was analyzed using Spearman's rank correlation coefficient. Results: The mean±SD of maternal age, gestational week and newborn birth weight of 773 mother-infant pairs were (28.34±4.50) years, (39.47±1.39) weeks and (3 419.47±497.39) g respectively. The median concentrations of Pb, Cd, As, Hg, Mn and As in maternal and cord blood were 31.12 and 30.02, 1.19 and 0.47, 8.05 and 6.03, 0.69 and 1.26, 100.70 and 105.55, 127.25 and 115.00 μg/L, respectively. The TTE of Pb, Cd, As, Hg, Mn, and Se was 0.98, 0.41, 0.73, 1.73, 0.96 and 0.91, respectively. Pb, Cd, Hg, Mn, and Se showed a significant positive correlation between maternal blood and cord blood, with Spearman correlation coefficients of 0.397, 0.298, 0.698, 0.555, and 0.285 (all P values<0.001). Conclusion: Each element was commonly detected in maternal blood and cord blood. The TTE of Hg was the highest.

HIV infection and electrocardiogram abnormalities: baseline assessment from the CHART cohort

OBJECTIVES

To investigate the prevalence of various electrocardiogram (ECG) abnormalities among HIV-positive and HIV-negative individuals.

METHODS

This cross-sectional evaluation included 1412 HIV-positive and 2824 HIV-negative participants aged 18 to 75 years and frequency matched by age and sex, derived from the baseline survey of Comparative HIV and Aging Research in Taizhou (CHART), China, between February and December 2017.

RESULTS

HIV-positive individuals had higher prevalence of sinus tachycardia (5.6% (79/1412) vs. 1.3% (36/2824), p < 0.001) and ST/T wave abnormalities (14.9% (211/1412) vs. 9.4% (264/1412), p < 0.001) but lower prevalence of sinus bradycardia (4.8% (68/1412) vs. 7.5% (211/2824), p 0.001); such associations remained statistically significant after adjusting for traditional risk factors (respectively, adjusted odds ratio (aOR) 4.68, 95% confidence interval (CI) 3.06-7.17; aOR 1.89, 95% CI 1.54-2.34; aOR 0.60, 95% CI 0.44-0.80). In adjusted models, being in higher carotid intima-media thickness categories was significantly associated with ST/T abnormalities in HIV-positive individuals only (0.78-1.00 mm: aOR 1.46, 95% CI 1.01-2.12; >1.00 mm: aOR 2.18, 95% CI 1.39-3.42), whereas being in higher blood pressure categories was significantly associated with both sinus tachycardia (prehypertension: aOR 5.61, 95% CI 1.76-17.91; hypertension: aOR 12.62, 95% CI 3.60-44.27) and ST/T abnormalities (hypertension: aOR 2.04, 95% CI 1.41-2.95) in HIV-negative individuals only. Longer duration of known HIV infection was the only HIV-specific factor of ST/T abnormalities (aOR 1.61, 95% CI 1.17-2.22), with none for sinus tachycardia.

CONCLUSIONS

HIV infection is independently associated with sinus tachycardia and ST/T abnormalities. Further research is needed to investigate specific mechanisms by which HIV infection leads to ECG abnormalities and to evaluate whether inclusion of ECG parameters improves cardiovascular disease prediction. Integrating ECG screening into routine HIV care is recommended in China.

[Effect of the number of previous spontaneous abortions on the first in vitro fertilization cycle]

Objective: To investigate the effect of the number of previous spontaneous abortions on the first in vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) cycle. Methods: A retrospective case-control study was conducted to analyze the clinical data of 1 279 patients who received IVF/ICSI treatment for the first time from July 2014 to July 2018 in Tianjin Central Hospital of Gynecology Obstetrics;they were divided into 0 time group (group A, n=924), 1 time group (group B, n=267) and 2 times group (group C, n=88) for comparison, according to the previous frequency of spontaneous abortions. Results: There were no statistically significant differences in age, basal testosterone, estradiol, progesterone, prolactin and embryo quality in group A, B and C (all P>0.05). The biochemical pregnancy rate of group C (9.1%) was higher than those of the other two groups (4.1% and 4.1%; all P>0.05). The clinical pregnancy rate of group A (42.5%) [>group B (40.4%) and >group C (35.2%)] was not statistically significant(P>0.05).Early abortion rate in group A (8.9%) was<group B (15.7%), also <group C (38.7%), there were significant differences (all P<0.05).The live birth rate of group C (21.6%) was significantly lower than that of group A (35.5%; P<0.05), but the difference between group C and group B (30.7%) was not statistically significant (P>0.05). Conclusions: Women with a history of one- or two-time spontaneous abortion have no obvious effect on embryo quality, and have a negative impact of clinical pregnancy rate, early abortion rate, live birth rate in the first IVF/ICSI cycle; especially for patients with a history of two times spontaneous abortion, early abortion rate has a significant increase, live birth rate decreases significantly, suggesting that patients with a history of two times of spontaneous abortion should find the causes of miscarriage according to the process of recurrent spontaneous miscarriage and receive treatment if necessary before subsequent pregnancy.

P978Core to block: a new ablation strategy for treating persistent atrial fibrillation

Background

Ablation strategy targeting the core of atrial fibrillation (AF) rotors alone can lead to both stabilisation and destabilisation of rotational activity. Non-contact dipole density mapping system is designed to rapidly identify dynamic regional atrial activation patterns of interest (API) during AF.

Purpose

To assess the feasibility of an ablation strategy consisted of pulmonary vein isolation + targeting the core of APIs followed by linear ablation to the nearest non-conducting boundary to treat persistent AF.

Methods

The ablation strategy includes: 1. Antral pulmonary vein electrical isolation (APVI); 2. APIs (focal, localised rotational and localised irregular activation; Figure1) detection by dipole density mapping; 3. API core ablation followed by linear ablation to the nearest non-conduction barrier (APVI/mitral valve); 4. repeat step 2 and 3 in LA (RA, if necessary) until sinus rhythm is achieved.

Results

Consecutive 40 persistent AF patients (mean 62±12 years, 29 males, AF duration 10±4 months, LA diameter 42±9 mm) were included from 2 centres. An average of 2.0±0.7 APIs per patient were targeted post-APVI. Acute AF termination by ablation was achieved in 27/40 (68%) patients. The mean ablation time of APVI and “Core to block” was 33±12 mins and 31±22 mins, respectively. No major complication occurred. During a mean follow-up of 12±5 months, 32/40 patients (80%) maintained sinus rhythm.

Conclusion

APVI + “Core to block” guided by the dipole density mapping is feasible for treating persistent AF. A larger randomised study is needed to test the effectiveness of this ablation strategy.

Acknowledgement/Funding

None

P3756Diverse activation patterns during persistent atrial fibrillation characterised by dipole density non-contact mapping

Background

Global simultaneous recording of activation during atrial fibrillation (AF) can elucidate underlying mechanisms contributing to AF maintenance. A better understanding of these mechanisms may allow for a personalised ablation strategy to treat persistent AF.

Purpose

To characterise left atrial endocardial activation patterns during AF using a novel non-contact dipole density mapping.

Methods

Activation patterns were characterised into three sub-types: (i) focal with centrifugal activation (FCA); (ii) localised rotational activation (LRA); (iii) localised irregular activation (LIA). Continuous activation patterns were quantified and distributed in the left atrium.

Results

A total of 144 persistent AF segments with 1068 activation patterns from 25 patients were analysed. The most common pattern was LIA (63%), which consist of four disparate features: slow conduction (45%), pivoting (30%), collision (16%) and acceleration (7%). LRA was the second commonest pattern (20%). FCA (17%) arose frequently from the PVs/ostia. Continuous AF activations comprise multiple combinations of FCA, LRA and LIA, transitioning from one to the next without a discernible order. Preferential conduction areas were typically seen in mid-anterior (48%) and lower-posterior (40%) walls where dominant activations were made up of LRA and LIA.

Conclusion

AF is characterised by heterogenous activation patterns that vary between individuals. Clinical implications of individualised ablation strategies guided by dipole density mapping will have to be determined.

Acknowledgement/Funding

None

Clinical evaluation of total and high-avidity anti-dsDNA antibody assays for the diagnosis of systemic lupus erythematosus

Background

This study evaluated the diagnostic performances of total and high-avidity (HA) anti-dsDNA enzyme immunoassays (EIA) in Chinese systemic lupus erythematosus (SLE) patients.

Methods

A total of 410 serum samples from 217 SLE patients, 54 patients with other systemic autoimmune diseases, and 139 healthy subjects were tested on total and HA anti-dsDNA EIA, as well as three commercial in vitro diagnostic kits: BioPlex 2200 ANA Screen, Kallestad anti-dsDNA EIA, and Crithidia Lucilae IFA. The disease activities of SLE patients were assessed using the modified SLE Disease Activity Index. The diagnostic performances of each assay were analyzed using Analyse-it software.

Results

The diagnostic performances of the total and HA anti-dsDNA EIA kits were comparable to other commercially available in vitro diagnostic assays. Receiver operating characteristic curve analysis demonstrated an area under the curve ranging from 0.85 to 0.89, with the total anti-dsDNA kit demonstrating the highest sensitivity and the HA kit showing higher specificity. An overall agreement of >90% was observed between the total and HA anti-dsDNA EIA kits and commercially available quantitative anti-dsDNA kits. The ratio of HA to total anti-dsDNA antibody was significantly higher among SLE patients with active disease status and/or kidney damage. All assays exhibited a significant correlation with disease activity and multiple clinical manifestations.

Conclusions

While the clinical performances of various anti-dsDNA assays showed adequate agreements, the BioPlex 2200 anti-dsDNA assay demonstrated the highest positive likelihood ratio and odds ratio. The HA anti-dsDNA EIA kit in association with the total anti-dsDNA kit provided superior performance in SLE diagnosis and monitoring disease activity.

AAV9 Edits Muscle Stem Cells in Normal and Dystrophic Adult Mice

CRISPR editing of muscle stem cells (MuSCs) with adeno-associated virus serotype-9 (AAV9) holds promise for sustained gene repair therapy for muscular dystrophies. However, conflicting evidence exists on whether AAV9 transduces MuSCs. To rigorously address this question, we used a muscle graft model. The grafted muscle underwent complete necrosis before regenerating from its MuSCs. We injected AAV9.Cre into Ai14 mice. These mice express tdTomato upon Cre-mediated removal of a floxed stop codon. About 28%-47% and 24%-89% of Pax7+ MuSCs expressed tdTomato in pre-grafts and regenerated grafts (p > 0.05), respectively, suggesting AAV9 efficiently transduced MuSCs, and AAV9-edited MuSCs renewed successfully. Robust MuSC transduction was further confirmed by delivering AAV9.Cre to Pax7-ZsGreen-Ai14 mice in which Pax7+ MuSCs are genetically labeled by ZsGreen. Next, we co-injected AAV9.Cas9 and AAV9.gRNA to dystrophic mdx mice to repair the mutated dystrophin gene. CRISPR-treated and untreated muscles were grafted to immune-deficient, dystrophin-null NSG.mdx4cv mice. Grafts regenerated from CRISPR-treated muscle contained the edited genome and yielded 2.7-fold more dystrophin+ cells (p = 0.015). Importantly, increased dystrophin expression was not due to enhanced formation of revertant fibers or de novo transduction by residual CRISPR vectors in the graft. We conclude that AAV9 effectively transduces MuSCs. AAV9 CRISPR editing of MuSCs may provide enduring therapy.

Plasma C-type lectin-like receptor 2 as a predictor of death and vascular events in patients with acute ischemic stroke

BACKGROUND AND PURPOSE

C-type lectin-like receptor 2 (CLEC-2) has prominent involvement in platelet activation, which is increased in coronary heart disease and acute ischaemic stroke (AIS) and is associated with stroke progression and stroke prognosis. Here, the aim was to examine the prognostic value of CLEC-2 in death and vascular event recurrence in AIS patients.

METHODS

In all, 352 patients with AIS were studied prospectively. All patients were followed up for 1 year. Death for all vascular events and a combination of death and vascular diseases (recurrent stroke, myocardial infarction, hospitalized and treated angina, hospitalized and treated peripheral arterial disease) were recorded.

RESULTS

During 1 year of follow-up, 46 patients (14.2%) experienced death or combined end-points (23 death and 46 combined end-points). Plasma CLEC-2 (pCLEC-2) was significantly associated with an increased risk of death and combined events of death and vascular diseases after adjusting for age, sex, history of hypertension, diabetes mellitus and coronary artery disease, and National Institutes of Health Stroke Scale scores. Each 1 SD higher log-transformed pCLEC-2 was associated with a 4.27-fold (hazard ratio 4.27, 95% confidence interval 1.71-10.65) increased risk for death and a 2.42-fold increased risk for combined end-points (hazard ratio 2.42, 95% confidence interval 1.52-3.86). The optimal cut-off point of pCLEC-2 for predicting death was 184.38 pg/ml.

CONCLUSIONS

Higher pCLEC-2 levels at admission were associated with increased risk of death and combined events of death and vascular diseases in patients with AIS, which indicated that pCLEC-2 is an important prognostic factor for AIS.

Ultrasonic microwave-assisted extraction coupled with macroporous resin chromatography for the purification of antioxidant phenolics from waste jackfruit (Artocarpus heterophyllus Lam.) peels

An efficient ultrasonic microwave-assisted extraction (UMAE) coupled with macroporous resin chromatography technique was successfully used for the extraction and purification of antioxidant phenolics from jackfruit by-products (peels). After optimization by single factor experiments and response surface methodology, the optimum extraction conditions for UMAE were: ethanol concentration 63%, solvent-to-solid ratio 34 mL/g, microwave power 160 W and irradiation time 20 min. Under the optimal condition, the phenolics extraction yield was 8.14 mg GAE/g DW. After the purification by macroporous resin AB-8, the purity of antioxidant phenolics from UMAE extracts improved from 13.59 to 49.07%. Furthermore, ABTS radical scavenging activities were also significantly increased from 35.95 ± 2.21 to 162.36 ± 10.26 mg TE/g. HPLC analysis revealed that gallic acid, chlorogenic acid, and catechin were three dominant antioxidant phenolics in jackfruit peels. All of the results demonstrated that waste jackfruit peels could be utilized as a good source of phenolics with strong antioxidant activities in food and pharmaceutical industry.

Enhanced broadband spin Hall effects by core-shell nanoparticles

Spin-orbit interaction of light is ubiquitous in any optical system. However, the relevant spin Hall effects are usually weak for the light scattering from nanoparticles, making it challengeable to detect directly in experiment. In this paper, we demonstrate enhanced broadband spin Hall effects by using core-shell nanoparticles. The electric and magnetic dipoles can be tuned by the core-shell nanostructure with great freedom, and are excited simultaneously in a broadband spectrum, resulting in robust enhanced spin Hall shifts. Moreover, the coupling of the electric dipole and electric quadrupole gives rise to enhanced spin Hall shifts at both forward and backward directions. Numerical results from far-field and near-field verify the strong spin-orbit interaction of light. Our work offers a new way to exploit spin Hall effects in superresolution imaging and spin-dependent displacement sensing.

Genetic analysis of skinfold thickness and its association with body condition score and milk production traits in Chinese Holstein population

The skin has many important roles in dairy cattle, and skinfold thickness could be used as an indicator of body fat deposition. The objectives of this study were to estimate genetic parameters of skinfold thickness and to explore its association with body condition score (BCS) and milk production traits in a Chinese Holstein population. Skinfold thicknesses over the neck (STN) and the last rib (STR), BCS, and test-day records of milk production traits were available for 6,416 lactating Holstein cows in the summers of 2015 and 2016 in Beijing, China. Multi-trait animal models were used to estimate variance and covariance components using the DMU software. The average STN was 7.15 ± 1.28 mm, and the average STR was 11.76 ± 1.95 mm (mean ± standard deviation). Estimated heritability was 0.13 ± 0.03 for STN and 0.26 ± 0.04 for STR. We detected a high genetic correlation (0.79 ± 0.08; heritability ± standard error) between STN and STR. Genetic correlations between skinfold thickness and BCS were low to moderate: 0.18 between STR and BCS, and 0.33 between STN and BCS. Genetic correlations between skinfold thickness and milk yield, milk fat percentage, and milk protein percentage were negligible, ranging from -0.02 to 0.15. Collectively, skinfold thickness is characterized as a trait with moderate heritability. Skinfold thickness is sensitive to changes in body condition or fat deposition across parities and lactation stages in milking cows, and we confirmed the complementary nature of skinfold thickness and BCS genetically as well as phenotypically by comparing their changing trends throughout lactation and across lactations. The use of skinfold thickness, together with BCS, can assist in the monitoring of changes in body fat deposition to achieve higher management precision.

[The effects of prenatal exposure to brominated diphenyl ethers-209 to the influence of male offspring rats hippocampus BDNF potein expression and its mechanism of action]

Objective: The effects of prenatal exposure to brominated diphenyl ethers-209 to the Influence of male offspring rats hippocampus BDNF potein expression and its mechanism of action. Methods: Pregnant Sprague-Dawley (SD) rats were randomly treated with BDE-209 (100, 300, and 900 mg/kg body weight) or corn oil by gavage on gestational days 6-20. Blood was obtained through heart puncture for thyroid hormone analysis in male rats offspring on PND 60. The hippocampus tissues were excised. The expression levels of BDNF protein were measured by Western blot. Results: 1) In hippocampal tissue, BDNF protein expression concentration ratio relative to the control group (control group concentration of 1) were 0.87 (300 mg/kg dose group) and 0.67 (900 mg/kg) (P<0.01) . 2) Compared to controls, total T4 levels and free T4 levels were significantly decreased in the BDE-209 treated-group (900 mg/kg, 300 mg/kg) (P<0.05) . Total T3 levels in 300 mg/kg group were also significantly decreased compared to the control (P<0.05) . However, no significant difference was observed in 100 mg/kg group (P>0.05) . Conclusion: During 300 and 900 mg/kg dose group of BDE-209 exposure to male offspring BDNF protein expression in rat hippocampus decreased, may be related to its interference with thyroid hormone.

The embryonic and evolutionary boundaries between notochord and cartilage: a new look at nucleus pulposus-specific markers

The adult nucleus pulposus (NP) and articular cartilage are similar in terms of their histocytological components and biomechanical functionalities, requiring a deep understanding of NP-specific markers to better evaluate stem-cell-based NP regeneration. Here, we seek to distinguish NP cells from articular chondrocytes (ACs), focusing on differences in their embryonic formation and evolutionary origin. Embryonically, NP cells are conservatively derived from the axial notochord, whereas ACs originate in a diversified manner from paraxial mesoderm and neural crest cells. Evolutionarily, although the origins of vertebrate NP and AC cells can be traced to similar structures within protostomia-like bilaterian ancestors, the distant phylogenetic relationship between the two groups of animals and the differences in the bodily origins of the tissues suggest that the tissues may in fact have undergone parallel evolution within the protostomia and deuterostomia. The numbers of supposedly NP-specific markers are increasing gradually as microarray studies proceed, but no final consensus has been attained on the specificity and physiology of "exclusive" NP markers because of innate variations among species; intrinsic expression of genes that destabilize the circadian clock; and cooperation by, and crosstalk among, different genes in terms of physiology-related phenotypes. We highlight the embryonic and evolutionary boundaries between NP and AC cells, to aid in recognition of the challenges associated with evaluation of the role played by nucleopulpogenic differentiation during stem-cell-based intervertebral disc regeneration.

Effect of peer support on diabetes distress: a cluster randomized controlled trial

AIM

To investigate whether peer support would reduce diabetes distress and improve glycaemic control when added to usual diabetes education among adults with Type 2 diabetes in China.

METHODS

We conducted a cluster randomized trial involving 400 adults with Type 2 diabetes from eight communities in Nanjing. All participants received usual education for an average of 2 h each month from physicians, certified diabetes educators, dieticians, psychologists and podiatric nurses. Peer support was led by trained peer leaders and included diabetes knowledge- and skills-sharing at least once a month, as well as peer-to-peer communication. The primary outcome was diabetes distress measured using the Diabetes Distress Scale at 12 months. Secondary outcomes included fasting plasma glucose, 2-h postprandial glucose and HbA_1c concentration. Outcome data were collected from all participants at baseline, 6 months and 12 months.

RESULTS

From 2012 to 2013, there were 200 participants in each study arm at baseline. Compared with the usual education arm, the peer support with usual education arm had greater reductions in regimen-related distress (1.4 ± 0.6 vs 1.2 ± 0.4; P=0.004) and total distress (1.3 ± 0.4 vs 1.2 ± 0.3; P=0.038) at 6 months. At 12 months, the scores for emotional burden (1.2 ± 0.3 vs 1.4 ± 0.6; P=0.002), physician-related distress (1.1 ± 0.3 vs 1.3 ± 0.4; P=0.001) and total scores (1.2 ± 0.3 vs 1.3 ± 0.4; P=0.002) were significantly lower in the peer support with usual education arm than in the usual education arm. Fasting plasma glucose levels were lower in the peer support with usual education arm than in the usual education arm at 6 months (7.5 ± 1.95 vs 8.0 ± 2.2; P=0.044) and 12 months (7.0 ± 2.3 vs 7.6 ± 1.5; P=0.008).

CONCLUSIONS

Beyond the benefits of usual education, peer support was effective in reducing diabetes distress for Type 2 diabetes mellitus. (Clinical Trials Registry no: NCT02119572).

Interferon-gamma response to the treatment of active pulmonary and extra-pulmonary tuberculosis

BACKGROUND

Interferon-gamma (IFN-γ) release assays (IGRAs) are used to diagnose tuberculosis (TB) but not to measure treatment response.

OBJECTIVE

To measure IFN-γ response to active anti-tuberculosis treatment.

DESIGN

Patients from the Henan Provincial Chest Hospital, Henan, China, with TB symptoms and/or signs were enrolled into this prospective, observational cohort study and followed for 6 months of treatment, with blood and sputum samples collected at 0, 2, 4, 6, 8, 16 and 24 weeks. The QuantiFERON® TB-Gold assay was run on collected blood samples. Participants received a follow-up telephone call at 24 months to determine relapse status.

RESULTS

Of the 152 TB patients enrolled, 135 were eligible for this analysis: 118 pulmonary (PTB) and 17 extra-pulmonary TB (EPTB) patients. IFN-γ levels declined significantly over time among all patients (P = 0.002), with this decline driven by PTB patients (P = 0.001), largely during the initial 8 weeks of treatment (P = 0.019). IFN-γ levels did not change among EPTB patients over time or against baseline culture or drug resistance status.

CONCLUSION

After 6 months of effective anti-tuberculosis treatment, IFN-γ levels decreased significantly in PTB patients, largely over the initial 8 weeks of treatment. IFN-γ concentrations may offer some value for monitoring anti-tuberculosis treatment response among PTB patients.