Resolvin D1 inhibits T follicular helper cell expansion in systemic lupus erythematosus

OBJECTIVE

Resolvin D1 (RvD1) is one of the specialized pro-resolving lipid mediators, which control inflammation resolution and regulate immune responses. Previous research showed that RvD1 could block the progression of systemic lupus erythematosus (SLE). However, the detailed mechanism remains to be fully understood.

METHOD

Plasma RvD1 levels, and proportions of T follicular helper cells (Tfh cells) were measured in SLE patients and healthy controls. Plasma RvD1 levels and proportions of Tfh cells were quantitated in an MRL/lpr mouse model of lupus treated with RvD1. Naïve CD4+ T cells were purified from MRL/lpr mice to study the effect of RvD1 on Tfh cell differentiation in vitro.

RESULTS

In patients, there were significant negative correlations between plasma RvD1 levels and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, as well as between plasma RvD1 and anti-double-stranded DNA antibody levels, and numbers of peripheral Tfh cells and plasma cells. In MRL/lpr mice, the expected amelioration of disease phenotype and inflammatory response with RvD1 treatment correlated with decreased percentages of Tfh cells and plasma cells. In addition, the differentiation and proliferation of Tfh cells were markedly suppressed by RvD1 in vitro.

CONCLUSION

RvD1 may control SLE progression through the suppression of Tfh cell differentiation and subsequent inhibition of B-cell responses.

Phase II clinical trial of neoadjuvant anti-PD-1 (toripalimab) combined with axitinib in resectable mucosal melanoma

BACKGROUND

The outcome of patients with resectable mucosal melanoma is poor. Toripalimab combined with axitinib has shown impressive results in metastatic mucosal melanoma with an objective response rate of 48.3% and a median progression-free survival of 7.5 months in a phase Ib trial. It was hypothesized that this combination administered in the neoadjuvant setting might induce a pathologic response in resectable mucosal melanoma, so we conducted this trial.

PATIENTS AND METHODS

This single-arm phase II trial enrolled patients with resectable mucosal melanoma. Patients received toripalimab 3 mg/kg once every 2 weeks (Q2W) plus axitinib 5 mg two times a day (b.i.d.) for 8 weeks as neoadjuvant therapy, then surgery and adjuvant toripalimab 3 mg/kg Q2W starting 2 ± 1weeks after surgery for 44 weeks. The primary endpoint was the pathologic response rate according to the International Neoadjuvant Melanoma Consortium recommendations.

RESULTS

Between August 2019 and October 2021, 29 patients were enrolled and received treatment, of whom 24 underwent resection. The median follow-up time was 34.2 months (95% confidence interval 20.4-48.0 months). The pathologic response rate was 33.3% (8/24; 4 pathological complete responses and 4 pathological partial responses). The median event-free survival for all patients was 11.1 months (95% confidence interval 5.3-16.9 months). The median overall survival was not reached. Neoadjuvant therapy was tolerable with 8 (27.5%) grade 3-4 treatment-related adverse events and no treatment-related deaths. Tissue samples of 17 patients at baseline and after surgery were collected (5 responders and 12 nonresponders). Multiplex immunohistochemistry demonstrated a significant increase in CD3+ (P = 0.0032) and CD3+CD8+ (P = 0.0038) tumor-infiltrating lymphocytes after neoadjuvant therapy, particularly in pathological responders.

CONCLUSIONS

Neoadjuvant toripalimab combined with axitinib in resectable mucosal melanoma demonstrated a promising pathologic response rate with significantly increased infiltrating CD3+ and CD3+CD8+ T cells after therapy.

Sequential left ventricular electro-mechanical changes in left bundle branch pacing vs right ventricular pacing a two-center study

Background

Left bundle branch pacing (LBBP) has been proved to maintain electrical synchrony better than RVP during mid to long-term follow-up, but little is known about the left ventricular (LV) mechanical changes over time. This study investigates if LBBP causes less sequential electro-mechanical alterations in LV that develop over time, compared with both conventional (CRVP) and leadless (LRVP) RVP.

Methods

Sixty-five patients with pacing indication for bradycardia were prospectively enrolled: Twenty-two were treated with LBBP, 23 with CRVP and 20 with LRVP. QRS duration (QRSd) was measured at baseline and during follow-up. All patients underwent echocardiography at baseline, one week after implantation and at one-year follow-up. LV volumes, ejection fraction (EF) and global longitudinal strain (GLS) were measured. Septal flash (SF), apical rocking and septal longitudinal strain patterns were assessed visually by two experienced readers.

Results

All the patients presented with normal strain pattern and no signs of SF or apical rocking at baseline. 100% of CRVP and 95% of LRVP patients had stage1 or 2 septal deformation patterns at week 1, and the majority (72.3% CRVP and 83.3% LRVP) progressed to stage≥2 at 12 months. On the contrary, over 2/3 of LBBP patients preserved normal strain patterns at week 1, and less than 1/3 had stage-1 pattern, 2 out of whom progressed to stage-2 during follow-up (Figure 1). At week 1 and 12 months, all RVP patients had SF, and most of them also exhibited apical rocking (87%-94.4% in CRVP and 80%-94.4% in LRVP). However, much less septal flash and apical rocking was induced in LBBP patients at week 1 and last follow-up (27.3%-37.5% and 22.7%-25%, P<0.001 vs RVP). Baseline QRSd were similar among three groups. At week 1, the paced QRSd increased least in LBBP compared to CRVP and LRVP and remained as such at 12 months. During one year follow-up, LVEF and LV GLS decreased more in CRVP group compared to LBBP (both P<0.05) (Figure 2).

Conclusion

LBBP causes less sequential changes in LV deformation patterns, septal flash and apical rocking, compared to CRVP and LRVP. With this, LBBP appears to preserve LV function better than RVP. CRVP and LRVP did not differ in electro-mechanical changes or LV remodeling.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Research Foundation Flanders (FWO) project grant

Left bundle branch pacing is superior in preserving ventricular mechanical synchrony and cardiac function than right ventricular pacing: a two-center experience

Background

Left bundle branch pacing (LBBP) has emerged as a novel pacing modality. Although it has been proved to maintain electrical synchrony better than right ventricular pacing (RVP), little is known about the impact on mechanical synchrony. This study investigates if LBBP preserves mechanical synchrony and cardiac function better compared to conventional (CRVP) and leadless (LRVP) RVP.

Methods

Sixty-five patients with pacing indication for bradycardia were prospectively enrolled: Twenty-two were treated with LBBP, 23 with CRVP and 20 with LRVP. All patients underwent echocardiography before and after implantation and at one-year follow-up. Left ventricular (LV) volumes, ejection fraction (EF) and global longitudinal strain (GLS) were measured. Regional septal (SW) and lateral wall work (LW) was calculated as the average from the respective basal and mid-ventricular segments in the apical four-chamber and three-chamber view. The lateral-septal work difference (LSWD) was used as a measure of mechanical dyssynchrony.

Results

At baseline, the QRS duration and LSWD were similar in all three groups. During follow-up, the QRS duration increased least in LBBP compared to CRVP and LRVP (+28.1±18.3ms vs +58.2±31.4 and 47.1±26.1ms, both P<0.01). SW was markedly decreased in CRVP and LRVP while LW work remained unchanged, resulting in a large LSWD compared to LBBP (1308.4±732.9 mmHg*% and 1451.3±606.1 mmHg*% vs. 286.0±479.9mmHg*%, both P<0.001). During one year follow-up, LVEF and LV GLS decreased more in CRVP compared to LBBP (both P<0.05).

Conclusion

LBBP causes less LV dyssynchrony than CRVP and LRVP as it preserves a more physiologic conduction pattern. With this, LBBP appears to preserve LV function better than CRVP. CRVP and LRVP did not differ in mechanical dyssynchrony or LV remodelling.

Funding Acknowledgement

Type of funding sources: None.

Cumulative incidence and risk factors of brain metastasis for acral and mucosal melanoma patients with stages I-III

PURPOSE

Few studies focused on the incidence of brain metastasis in patients with acral and mucosal melanoma, and a better understanding of the incidences and predictors of brain metastasis is needed in these patients.

METHOD

A prospectively accrued cohort of 799 patients with acral and mucosal melanoma in stages I-III from July 2011 to December 2015 at Peking University Cancer Hospital were included in this study. Competing risk models (Fine and Gray) were used to estimate the cumulative incidence of brain metastasis and compare the differences in cumulative incidence curves between different primary lesions, stages, and molecular types.

RESULTS

At a median follow-up time of 68.0 months, 60 of the 779 patients (7.7%) developed brain metastasis, and 261 (33.5%) patients developed extracranial metastasis. Considering the risk of competition, the cumulative incidence of brain metastasis at one year, two years, and five years after diagnosis were 5.1%, 10.2%, and 19.5%, respectively. Stage III, BRAF mutations, and NRAS mutations were associated with a high risk of brain metastasis in univariable analysis. Multivariate analysis showed BRAF mutations, and NRAS mutations had statistically correlated with an increased cumulative incidence of brain metastasis at diagnosis and all-time point of one year and two years after diagnosis.

CONCLUSION

This study is the first to report the cumulative incidence and risk factors of brain metastasis for patients with acral and mucosal melanoma in stages I-III. Patients with BRAF and NRAS mutations had a higher incidence at diagnosis and all-time point, providing the basis for surveillance guidelines and further mechanic exploration.

High glucose inhibits the survival of HRMCs and its mechanism

OBJECTIVE

High glucose can promote the apoptosis of glomerular mesangial cells and cause diabetic nephropathy (DN). However, the mechanism remains unclear. In the present study, we investigated the effects of high glucose on the survival of human renal mesangial cells (HRMCs).

MATERIALS AND METHODS

Cells were treated with high glucose (30 mM) or normal glucose (5 mM) for 48 hours. Cell proliferation was determined by trypan blue assay. The relative expression of metalloproteinase-3 (TIMP3) and inflammatory factors detected by real-time polymerase chain reaction (PCR). Protein expression of Smad2/3, p-Smad2/3 and Smad7 in HRMCs were analyzed by Western blot.

RESULTS

Compared with normal glucose, we found that high glucose significantly inhibited cell survival, accompanied by the decrease of tissue metalloproteinase-3 (TIMP3) mRNA expression. Western blot results showed that the expression of p-Smad2/3 was significantly up-regulated, the expression of Smad7 was significantly downregulated, and inflammatory factors IL-6/IL-8 mRNA expression were increased in the HRMCs cultured with the high glucose. We also found that, compared with the normal glucose, the level of MDA was significantly increased (p<0.01), and the level of SOD was significantly lower (p<0.05) in the HRMCs cultured with the high glucose.

CONCLUSIONS

These findings suggested that high glucose inhibited the survival of HRMCs and may be associated with the downregulation of TIMP3 expression, Smad signaling pathway, inflammation and oxidative stress.

Relationship of resting heart rate and blood pressure with all-cause and cardiovascular disease mortality

OBJECTIVES

This study aimed to investigate associations of resting heart rate (RHR) and blood pressure (BP) with all-cause and cardiovascular disease (CVD) mortality.

STUDY DESIGN

A retrospective cohort study.

METHODS

A total of 67,028 Chinese participants aged ≥60 years were included in the analysis. RHR, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were evaluated according to quartiles ([41-69, 70-74, 75-79, 80-127 beats/min], [80-119, 120-129, 130-139, 140-238 mm Hg], and [40-70, 71-79, 80-84, 85-133 mm Hg]). Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) of all-cause and CVD mortality with RHR, SBP, and DBP. Restricted cubic splines were used to evaluate the dose-response association.

RESULTS

During the 361,975 person-year follow-up, 9326 deaths were recorded, of which 5039 deaths were due to CVD. The risk of all-cause mortality was increased by 25% with the quartiles four vs quartile one of RHR (HR [95% CI]:1.25 [1.17-1.33]), and CVD mortality was increased by 32% (HR [95% CI]: 1.32 [1.22-1.44]). Similar results were observed when comparing the quartiles four vs quartile one of SBP with the risk of all-cause and CVD mortality (HRs [95% CIs]: 1.14 [1.07, 1.22] and 1.23 [1.12. 1.34]) and DBP with the risk of all-cause and CVD mortality (HRs [95% CIs]: 1.17 [1.11. 1.24] and 1.36 [1.26. 1.47]). We found linear associations of RHR, SBP, and DBP with all-cause and CVD mortality (P_{non-linearity} >0.05), except for the approximately J-shaped association between DBP and all-cause mortality (P_{non-linearity} = 0.008). There was a significant interaction of RHR and SBP with all-cause and CVD mortality (P_interaction <0.05).

CONCLUSIONS

RHR and BP increased the risk of all-cause and CVD mortality, especially fast RHR combined with high SBP.

Left bundle branch pacing preserves ventricular mechanical synchrony better than right ventricular pacing-a two-center study

Funding Acknowledgements

Type of funding sources: None.

Background

Left bundle branch pacing (LBBP) has emerged as a novel pacing method. We sought to evaluate left ventricular (LV) mechanical synchrony under permanent LBBP and compare it with conventional and leadless right ventricular pacing (CRVP, LRVP).

Methods

Sixty-four patients with pacing indication for bradycardia were prospectively enrolled. Twenty-two patients received LBBP in the basal ventricular septum. Twenty-three patients received CRVP and 19 LRVP. All patients underwent echocardiography before and after device implantation. Myocardial work was estimated by pressure-strain analysis. Regional work in the septum (SEP) and lateral wall (LW) was calculated as the average from the respective basal and mid-ventricular segments in the apical four-chamber and three-chamber view. The absolute difference between work in LW and SEP (LW-S-work difference) was used as a measure of asymmetry in workload.

Results

Baseline characteristics were similar among the three groups. The electrocardiogram during LBBP showed a right bundle branch block pattern; during CRVP and LRVP a left bundle branch block pattern. The paced QRS duration was 114.27±9.9 ms in the LBBP group, significantly shorter than that in the CRVP and LRVP groups (153.9±25.26 ms and 159.1±13.99ms, respectively, both p&lt;0.001). The SEP work decreased in all groups during ventricular pacing (all P&lt;0.05), while the LW work remained similar. The paced LW-S work difference and work difference change between pacing on and off were more significant in the CRVP (1012.9±566.0mmHg*%) and LRVP group (1066.1±472.6mmHg*%) than the LBBP group (260.5±239.8mmHg*%, both P&lt;0.001). In addition, LW-S work difference during ventricular pacing and work difference change between pacing and baseline were comparable in CRVP and LRVP group.

Conclusion

LBBP causes less LV dyssynchrony than CRVP and LRVP as it preserves a more physiologic conduction pattern. CRVP and LRVP did not differ in this respect. Further studies need to prove that LBBP has advantages over RVP with regards to preservation of LV synchrony and contractility.

In vitro assessment of the DNA damage and senility of CD117+ stem cells collected from diabetic mice

OBJECTIVE

Angiogenesis impairment is a common feature of diabetes mellitus (DM), whereas CD117+ bone marrow cells (BMCs) injury might be responsible for such complication. In this study, we studied the effect of hyperglycemia on the DNA damage and senility of CD117+ bone marrow cells.

MATERIALS AND METHODS

We isolated CD117+ BMCs from the Streptozotocin (STZ) induced diabetes and healthy control mice. Oxidative stress was detected by flow cytometric analysis. γ-H2AX, which is the DNA damage mark, was detected by using Western blotting and immunofluorescence histochemistry. We also detected the expression of γ-H2AX and p16 by using Western blotting.

RESULTS

Compared with the control mice, the level of reactive oxygen species (ROS) was increased significantly in the CD117+ BMCs collected from the diabetic mice (p<0.05), and the percentage of γ-H2AX positive cells was higher significantly (p<0.01). The expression of γ-H2AX and p16 was increased significantly in the CD117+ BMCs from the diabetic mice.

CONCLUSIONS

Our experiments demonstrated the oxidative stress in CD117+ BMCs under DM conditions, while accelerating the DNA damage and senility in CD117+ BMCs as well.

Stability of a Novel PEGylation Site on a Putative Haemoglobin-Based Oxygen Carrier

PEGylation of protein sulfhydryl residues is a common method used to create a stable drug conjugate to enhance vascular retention times. We recently created a putative haemoglobin-based oxygen carrier using maleimide-PEG to selectively modify a single engineered cysteine residue in the α subunit (αAla19Cys). However, maleimide-PEG adducts are subject to deconjugation via retro-Michael reactions, with consequent cross-conjugation to endogenous plasma thiols such as those found on human serum albumin or glutathione. In previous studies mono-sulfone-PEG adducts have been shown to be less susceptible to deconjugation. We therefore compared the stability of our maleimide-PEG Hb adduct with one created using a mono-sulfone PEG. The corresponding mono-sulfone-PEG adduct was significantly more stable when incubated at 37 °C for 7 days in the presence of 1 mM reduced glutathione, 20 mg/mL human serum albumin, or human serum. In all cases haemoglobin treated with mono-sulfone-PEG retained >90% of its conjugation whereas maleimide-PEG showed significant deconjugation, especially in the presence of 1 mM reduced glutathione where <70% of the maleimide-PEG conjugate remained intact. Although maleimide-PEGylation of Hb seems adequate for an oxygen therapeutic intended for acute use, if longer vascular retention is required reagents such as mono-sulfone-PEG may be more appropriate.

A Priori Sample Size Determination for the Number of Subjects in an EEG Experiment

This paper represents a first attempt to perform a priori sample size determination from a "historic" Electroencephalography (EEG) dataset. The importance of adequate sample size is firstly highlighted, and evidence is given against the use of normal distribution for such computations, when the data cannot be assumed to be Gaussian. The "historic" dataset is then thoroughly examined to determine the least less likely underlying distribution for the desired phenomenon, in this case the spontaneous blinks potential. Two Monte Carlo simulations, using different distribution assumptions, are subsequently computed to estimate the a priori minimum sample size. Finally, these choices are discussed considering practical limitations, as well as the computational differences for other phenomena to study.

A new algorithm for blink correction adaptive to inter- and intra-subject variability

Electroencephalographic (EEG) signals are constantly superimposed with biological artifacts. In particular, spontaneous blinks represent a recurrent event that cannot be easily avoided. The main goal of this paper is to present a new algorithm for blink correction (ABC) that is adaptive to inter- and intra-subject variability. The whole process of designing a Brain-Computer Interface (BCI)-based EEG experiment is highlighted. From sample size determination to classification, a mixture of the standardized low-resolution electromagnetic tomography (sLORETA) for source localization and time restriction, followed by Riemannian geometry classifiers is featured. Comparison between ABC and the commonly-used Independent Component Analysis (ICA) for blinks removal shows a net amelioration with ABC. With the same pipeline using uncorrected data as a reference, ABC improves classification by 5.38% in average, whereas ICA deteriorates by -2.67%. Furthermore, while ABC accurately reconstructs blink-free data from simulated data, ICA yields a potential difference up to 200% from the original blink-free signal and an increased variance of 30.42%. Finally, ABC's major advantages are ease of visualization and understanding, low computation load favoring simple real-time implementation, and lack of spatial filtering, which allows for more flexibility during the classification step.