New latency-promoting agents for a block-and-lock functional cure strategy

PURPOSE OF REVIEW

Currently, HIV-infected patients are treated with antiretroviral therapy. However, when the treatment is interrupted, viral rebound occurs from latently infected cells. Therefore, scientists aim to develop an HIV-1 cure which eradicates or permanently silences the latent reservoir.

RECENT FINDINGS

Previously, scientists focused on the shock-and-kill cure strategy, which aims to eradicate the latent reservoir using latency-reactivating agents. Limited success shifts the interest towards the block-and-lock cure approach, which aims to achieve a functional cure by "blocking" HIV-1 transcription and "locking" the provirus in a deep latent state, resistant to treatment-interruption. In this strategy, latency promoting agents are used to induce transcriptional silencing and alter the epigenetics environment at the HIV promotor.

SUMMARY

For the block-and-lock cure strategy to succeed more investigation into the transcriptional and epigenetic regulation of HIV-1 gene expression is necessary to design optimal latency-promoting agents. In this review, we will discuss the latency promoting agents that have been described in literature during the past 2 years (2022-2023).

The role of marshall bundle epicardial connections in atrial tachycardias after atrial fibrillation ablation

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial tachycardias (ATs) are often seen in the context of AF ablation.

Objectives

We evaluated the role of the Marshall bundle (MB) network in left atrial (LA) ATs using high-density high-spatial resolution 3D mapping.

Methods

199 post-AF ablation LA tachycardias were mapped in 140 consecutive patients (112 (80%) males, mean age: 61.8 years); 133 (66.8%) were macro-reentrant and 66 (33.2%) were scar-related re-entry. MB-dependent perimitral AT (PMAT) was diagnosed where the difference between the post pacing interval and the tachycardia cycle length (PPI-TCL) was <20ms in parts of the expected MB-dependent perimitral circuit (within the VOM, the ridge between the left pulmonary veins and LA appendage (LAA), the anterior LA and between 6- and 11-o’clock of the mitral annulus) and the PPI-TCL was >20ms in areas bypassed by the VOM (the distal coronary sinus (CS), the posterior LA and the mitral isthmus). MB-related re-entry was diagnosed by PPI-TCL <20ms at the left lateral ridge, posterior base of LAA, inferolateral LA or VOM ostium; and PPI-TCL >20ms in the septal annulus. Typically, in MB-dependent localized re-entry, the earliest activation was found along the MB-LA endocardial connection or MB-CS epicardial connection. 

Results

The MB network was found to participate in 60 (30.2%) re-entrant ATs, 31 PMATs and 29 localized re-entries. High-frequency multiphasic fragmented electrograms with long duration were often recorded endocardially or epicardially at the MB-LA or MB-CS connections. The amplitude and duration of these signals were 0.5 ± 0.79 mV and 65 ± 40 ms for MB-PMATs and 0.26 ± 0.28mV and 122 ± 67 ms for MB-localized re-entries. Unipolar EGMs at the site of endocardial-epicardial breakthrough had a rS pattern in all MB-related ATs. Of 60 MB-related ATs, 49 (81.6%) terminated with RF ablation, 44 (73.3%) at the MB-LA junction and 5 (8.3%) at the MB-CS junction, while 9 (15%) terminated after 2.5-5 cc of alcohol infusion inside the vein of Marshall (VOM). Of the 31 MB-related macroreentrant ATs, 17 (54.8%) terminated at the MB-LA junction, 5 (16.1%) at the MB-CS junction and 7 (22.6%) with alcohol infusion inside the VOM. Two macroreentries (6.5%) using the MB did not terminate with RF energy either endocardially at the MB-LA junction or epicardially at the MB-CS junction, and we were unable to identify or cannulate the VOM for ethanol infusion. Of the 29 localized re-entrant ATs using the MB, 27 (93.1%) terminated at the MB-LA junction, none terminated at the MB-CS junction and 2 (6.9%) terminated after alcohol infusion. After a mean follow up of 12 months, only 4 patients (6.7%) had AT recurrence.

Conclusions

MB re-entrant ATs accounted for up to 29% of the left ATs after AF ablation. Ablation of the MB-LA or CS-MB connections or alcohol infusion inside the VOM is required to treat these arrhythmias. Abstract Figure.

5201Intra-cardiac thrombus in patients undergoing ventricular tachycardia ablation. a computed tomographic scan study

Background

Embolic event is one of the complications of VT ablation. This may be due to the presence of intra-cardiac thrombus before ablation. However, there is no clear consensus on how to rule out thrombus before the procedure.

Objective

We sought to examine the prevalence and risk factors of intra-cardiac thrombus with cardiac computed tomographic (CT) scan in patients undergoing scar-related VT ablation.

Methods

In absence of contra-indication, all patients undergoing scar-related VT ablation at our institution underwent contrast-enhanced cardiac CT within one week before ablation. 324 consecutive patients (292 male, 59±16 yo) have been included in this study. The etiology was ischemic cardiomyopathy (CMP) (n=191), arrhythmogenic right ventricular CMP (ARVC) (n=37), congenital CMP (n=11) or other CMP (n=85). LVEF was <40% in 154 patients (48%).

Results

Intra-cardiac thrombus was diagnosed in 29 (9%) patients: in the left atrium (n=8), in the right atrium (n=1), in the left ventricle (n=15), in the right ventricle (n=3), in right and left atrium (n=1), and in left atrium and right ventricle (n=1). Moreover in 2, a bilateral pulmonary embolism was identified. The population with thrombus was older (65±12 vs 58±16 years, p=0,005), with more permanent atrial fibrillation (AF) (28% vs 8%; p=0.005). Patients with left ventricular (LV) aneurysm were at higher risk of thrombus 50% vs 3% (p<0.001). The average CHADSVASC score was similar for both groups (2,5 vs 2,1; p=0.179). After matching for age and sex, only ischemic CMP and LV aneurysm were risk factors for thrombus. Because of arrhythmic storm, ablation was performed by epicardial approach only, in 5 patients with intra-ventricular thrombus and by retroaortic approach only, in 2 patients with LAA thrombus. No embolic event occurred during these procedures.

Conclusion

CT scans help eliminating intra-cardiac thrombus before VT ablation procedure. A high proportion of thrombus (9%) was identified. Whereas LV thrombus should systematically be ruled out before scar related VT ablation, in patients with AF, a LAA thrombus should also be eliminated as well as RV thrombus in patients with ARVC.

Acknowledgement/Funding

ANR-10-IAHU-04

Upper limb and hand patterns in cerebral palsy: Reliability of two new classifications

AIM

To evaluate the inter- and intra-rater reliability of two previously developed classifications of upper limb and hand patterns.

METHOD

Two hundred and twelve films of patients with CP (118 of UL postures and 94 of hand tasks; median age 14, 3-46 years) were viewed by 18 examiners from 2 different rehabilitation centers, and one expert who had participated in the design of the classifications. They classed upper limb (3 patterns with sub-types) and hand patterns (2 patterns with subtypes) twice, at 2 months' interval. Inter- and intra-rater reliability were analysed.

RESULTS

Intra-rater and inter-rater reliability were very high for upper limb and hand patterns (0.87 < k < 0.92), and high for the subtypes (0.58 < k < 0.68). Examiners stated that both classifications were useful and feasible in clinical practice.

INTERPRETATION

Despite the single, short training session on use of the classifications, agreement between the examiners and the expert examiner was good to high, confirming that these classifications are easy to use and reliable. The classifications proposed here provide homogenous terminology for use in both clinical practice and research, to describe, evaluate and follow-up changes in upper limb and hand patterns in patients with cerebral palsy, particularly those with dyskinesia.

Cluster randomized trial to evaluate the impact of team training on surgical outcomes

Background

The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation.

Methods

A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals.

Results

Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P &lt; 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P &lt; 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals.

Conclusion

Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).

Dolutegravir as monotherapy in HIV-1-infected individuals with suppressed HIV viraemia

BACKGROUND

Reducing drug burden is a key challenge for achieving lifelong suppressive HIV therapy. Dolutegravir, with a high potency, long half-life and high genetic barrier, offers potential for monotherapy.

METHODS

This observational single-centre study enrolled all patients with HIV RNA (viral load) <50 copies/mL for at least 12 months, with CD4 >350 cells/mm(3) and with no failure under integrase inhibitor therapy who had switched from suppressive ART to dolutegravir monotherapy (50 mg/day). Primary outcome was proportion of patients with viral load <50 copies/mL at week 24.

RESULTS

Twenty-eight patients treated for a median ART duration of 17 years (IQR 11-20), virally suppressed for a median of 79 months (IQR 42-95) and with a median CD4 count of 624 cells/mm(3) (IQR 524-761), were enrolled. Baseline ART consisted of a three-drug (n = 10), two-drug (n = 10) or single-drug (n = 8) regimen with integrase inhibitor exposure in 13 patients. The proportion of patients maintaining viral load <50 copies/mL was 96% (95% CI 79%-100%) at week 4, 100% (95% CI = 85%-100%) at week 8, 93% (95% CI 76%-99%) at week 12 and 92% (75-99) at week 24. Three patients (3.70%; 95% CI 3.4%-10.8%) with prior integrase inhibitor experience had HIV RNA rebound with the presence of resistance mutations. Genotyping of HIV DNA using the Sanger method or ultradeep sequencing showed no integrase inhibitor resistance-associated mutations (RAMs) except for the mutation 74I in a patient on a suppressive elvitegravir regimen. The median within- and between-subject variability of dolutegravir C24 was 25% and 34%, respectively. Nine patients with a year of follow-up remained virally suppressed.

CONCLUSIONS

Dolutegravir has the potency to be further investigated as a single ART in randomized studies, particularly in patients with no prior exposure to integrase inhibitors.

Trends of labile trace metals in tropical urban water under highly contrasted weather conditions

The spatio-temporal trend of trace metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in a tropical urban estuary under the influence of monsoon was determined using diffusive gradient in thin films (DGT) in situ samplers. Three different climatic periods were observed: period 1, dry with dredging activity; period 2, intermediate meaning from dry to wet event; and period 3, wet having continuous rainfall. Conforming to monsoon regimes, these periods correspond to the following: transition from winter to summer, winter, and summer monsoons, respectively. The distinction of each period is defined by their specific hydrological and physico-chemical conditions. Substantial concentrations of the trace metals were detected. The distribution and trend of the trace metals under the challenge of a tropical climate were able to follow using DGT as a sensitive in situ sampler. In order to identify the differences among periods, statistical analyses were performed. This allowed discriminating period 2 (oxic water) as significantly different compared to other periods. The spatio-temporal analysis was then applied in order to distinguish the trend of the trace metals. Results showed that the trend of trace metals can be described according to their response to (i) seasonal variations (Cd and Cr), (ii) spatio-temporal conditions (Co, Cu, Ni, and Pb), and (iii) neither (i) nor (ii) meaning exhibiting no response or having constant change (Zn). The correlation of the trace metals and the physico-chemical parameters reveals that Cd, Co, Cu, and Cr are proportional to the dissolved oxygen (DO), Cd and Ni are correlated pH, and Zn lightly influenced by salinity.

Implementation of a computerized system in pediatric wards to improve nutritional care: a cluster randomized trial

BACKGROUND/OBJECTIVES

Malnutrition occurs frequently in hospitalized children. We aimed to assess whether a computerized system could lead to improved clinical practices in malnourished children.

SUBJECTS/METHODS

Healthcare workers (242) from six departments in a pediatric university hospital participated in a cluster randomized trial, studying 1457 malnourished children hospitalized from September 2009 to August 2011. Following a baseline observational pre-intervention period, all departments were randomized into either intervention or control arms. A computerized malnutrition-screening system was implemented in the intervention group to automatically trigger a dietetic referral in real time. Furthermore, the nutrition support team conducted an awareness campaign with healthcare workers and a leadership-based strategy to reinforce the message during the entire study period. Adherence to practice guidelines (daily weights, investigation of etiology for malnutrition, management by a dietitian and application of refeeding protocols) was compared between pre- and post-intervention periods in both the intervention and trial arms.

RESULTS

When compared with the pre-intervention period, the clinical practices were significantly improved within the intervention arm for every outcome (P<0.01), whereas remained unchanged in the control arm. In addition, during the post-intervention period, malnutrition etiology investigation by physicians (adjusted odds ratio (OR) of 4.4, 95% confidence interval (CI) 1.7-11.8, P=0.003) and management by a dietitian (OR 2.7, 95% CI 1.0-6.9, P=0.046) occurred more frequently in the intervention clusters.

CONCLUSIONS

Implementation of an electronic system to detect malnutrition in real time was associated with a rapid improvement in clinical practices for better care of hospitalized children.

Prevalence, characteristics, and prognosis role of type 1 ST elevation in the peripheral ECG leads in patients with Brugada syndrome

BACKGROUND

Despite isolated reports of Brugada syndrome (BrS) in the inferior or lateral leads, the prevalence and prognostic value of ST elevation in the peripheral electrocardiographic (ECG) leads in patients with BrS remain poorly known.

OBJECTIVE

To study the prevalence, characteristics, and prognostic value of type 1 ST elevation and ST depression in the peripheral ECG leads in a large cohort of patients with BrS.

METHODS

ECGs from 323 patients with BrS (age 47 ± 13 years; 257 men) with spontaneous (n = 141) or drug-induced (n = 182) type 1 ECG were retrospectively reviewed. Two hundred twenty-five (70%) patients were asymptomatic, 72 (22%) patients presented with unexplained syncope, and 26 (8%) patients presented with sudden death (12 patients) or appropriated implantable cardioverter-defibrillator therapies (14 patients) at diagnosis or over a mean follow-up of 48 ± 34 months.

RESULTS

Thirty (9%) patients presented with type 1 ST elevation in at least 1 peripheral lead (22 patients in the aVR leads, 2 in the inferior leads, 5 in both aVR and inferior leads, and 1 in the aVR and VL leads). Patients with type 1 ST elevation in the peripheral leads more often had mutations in the SCN5A gene, were more often inducible, had slower heart rate, and higher J-wave amplitude in the right precordial leads. Twenty-seven percent (8 of 30) of the patients with type 1 ST elevation in the peripheral leads experimented sudden death/appropriate implantable cardioverter-defibrillator therapy, whereas it occurred in only 6% (18 of 293) of other patients (P < .0001). In multivariate analysis, type 1 ECG in the peripheral leads was independently associated with malignant arrhythmic events (odds ratio 4.58; 95% confidence interval 1.7-12.32; P = .0025).

CONCLUSIONS

Type 1 ST elevation in the peripheral ECG leads can be seen in 10% of the patients with BrS and is an independent predictor for a malignant arrhythmic event.