Phenotypic Characteristics Research Articles

Phenotypic Characterization of Subtype A and Recombinant AC Transmitted/Founder Viruses from a Rwandan HIV-1 Heterosexual Transmission Cohort

HIV-1 subtypes have distinct geographical distributions, with subtypes A, C, and D and inter-subtype recombinants circulating in sub-Saharan Africa. Historically, individuals living with subtype A viruses exhibit slower CD4 decline and progression to AIDS diagnosis. Despite this, there are few authentic infectious molecular clones (IMCs) of subtype A or AC recombinant transmitted founder (TF) viruses with which to investigate viral impacts on pathogenesis. In this study, we constructed 16 authentic subtype A1 and 4 A1C recombinant IMCs from the IAVI Rwandan Protocol C acute infection cohort and characterized these viruses phenotypically. The virus replicative capacity (RC) scores varied over 50-fold, but the natural substitution of non-consensus amino acids in the p17(MA) domain of Gag was generally linked to higher RC levels. Sensitivity to a panel of broadly neutralizing antibodies (bNAbs) showed that all but one TF was sensitive to N6, which targets the CD4 binding site, while bNAbs PG16 and PGT 128 had a similar level of potency but reduced breadth against our panel of viruses. In contrast, bNAb 10E8V4 revealed high breadth but much lower potency. This panel of well-characterized, authentic subtype A and AC recombinant IMCs provides a resource for studies on the role of the virus subtype in HIV-1 transmission, pathogenesis, and vaccine design.

CRISPR/Cas System in Human Genetic Diseases

Gene editing involves altering a particular sequence within an organism’s genome using gene-editing techniques. Efficiently and accurately insert, delete or replace genes to alter their genetic information and phenotypic characteristics. DNA nuclease-based gene editing technology has advanced rapidly, from the first-generation editing system ZFNs, the second-generation TALENs to the third-generation CRISPR/Cas9 system, the efficiency of gene editing has been continuously improved, the cost has been gradually reduced, and the application scope has been expanding. The new classification system categorizes CRISPR-Cas proteins into Class I and II as the two main classes. Class I encompasses several subtypes, including Type I, III, and IV, all form complexes through the coordinated function of multiple Cas proteins. While Class II includes Type II, Type V, and Type VI, which all rely on single large Cas protein to perform all response. By designing single guide RNA (sgRNA), CRISPR can be used to target any gene sequence intended to be edited, achieving the wanted therapeutic outcome in treatment of inherited genetic disease. Although potential for off-target leads to undesired genetic alterations even result in oncogenesis, CRISPR-Cas still works as powerful therapy and gene editing tool in all aspects. Future research requires us to solve off-target issue. This review systematically introduces CRISPR-Cas systems as promising therapeutic strategy towards various genetic disease, explaining molecular mechanism and classification of CRISPR and differences among them.

Biofilm-mediated antibiotic tolerance in Staphylococcus aureus from spinal cord stimulation device-related infections.

Staphylococcus aureus is a predominant cause of infections in individuals with spinal cord stimulation (SCS) devices. Biofilm formation complicates these infections, commonly requiring both surgical and antibiotic treatments. This study explored the biofilm matrix composition and antimicrobial susceptibility of planktonic and biofilm-growing S. aureus isolates from individuals with SCS-related infections. Whole-genome sequencing (WGS) examined genotypes, virulome, resistome, and the pan-genome structure. The study also analyzed biofilm matrix composition, early surface adhesion, hemolytic activity, and antibiotic-susceptibility testing. WGS revealed genetic diversity among isolates. One isolate, though oxacillin susceptible, contained the mecA gene. The median number of virulence factor genes per isolate was 58. All isolates harbored the biofilm-related icaA/D genes. When assessing phenotypic characteristics, all strains demonstrated the ability to form biofilms in vitro. The antimicrobial susceptibility profile indicated that oxacillin, rifampin, and teicoplanin showed the highest efficacy against S. aureus biofilm. Conversely, high biofilm tolerance was observed for vancomycin, trimethoprim/sulfamethoxazole, and levofloxacin. These findings suggest that S. aureus isolates are highly virulent and produce robust biofilms. In cases of suspected biofilm infections caused by S. aureus, vancomycin should not be the primary choice due to its low activity against biofilm. Instead, oxacillin, rifampin, and teicoplanin appear to be more effective options to manage SCS infections.IMPORTANCESCS devices are increasingly used to manage chronic pain, but infections associated with these devices, particularly those caused by Staphylococcus aureus, present significant clinical challenges. These infections are often complicated by biofilm formation, which protects bacteria from immune responses and antibiotic treatments, making them difficult to eradicate. Understanding the genetic diversity, virulence, and biofilm characteristics of S. aureus isolates from SCS infections is critical to improving treatment strategies. Our study highlights the need to reconsider commonly used antibiotics like vancomycin, which shows reduced activity against biofilm-growing cells. Identifying more effective alternatives, such as oxacillin, rifampin, and teicoplanin, provides valuable insight for clinicians when managing biofilm-related S. aureus infections in patients with SCS implants. This research contributes to the growing evidence that biofilm formation is crucial in treating device-related infections, emphasizing the importance of tailoring antimicrobial strategies to the biofilm phenotype.

Exploring the Role of Endophytes in Cannabis sativa L. Polyploidy and Agricultural Trait Improvement

Here, we examine the effects of ploidy variation in Cannabis sativa L. cell lines on the plant host genotype-associated microbiome. The endophytic microbiome has a protocooperative role in improving plant health and productivity and represents an alternative to synthetic chemical fertilizers and pesticides in sustainable agriculture. This study assessed the effects of seed endophytes on diploid and triploid Haze hemp cultivars. Key phenotypic characteristics were evaluated, revealing significant differences in seed germination in vitro as well as vegetative growth and flowering in phytotron conditions. Endophyte-treated triploid plants exhibited significantly taller heights compared to diploids (p < 0.01). These treated triploid plants also showed longer leaves at nodes 2, 6, and 8, except at node 4, indicating a plant in transition from vegetative growth to the generative developmental stage. Additionally, triploids treated with endophytes displayed the highest number of axillary branches, while endophyte-treated diploids had the fewest (p < 0.05). Both cultivars treated with endophytes exhibited a higher number of inflorescences compared to untreated control plants. This study revealed for the first time a direct correlation between the shifts in diameter of the stem and the biomass in both tested hemp hosts, in association with endophytic microbiomes.

A host shift as the origin of tomato bacterial canker caused by Clavibacter michiganensis.

The Actinomycetota (formerly Actinobacteria) genus Clavibacter includes phytopathogens with devasting effects in several crops. Clavibacter michiganensis, the causal agent of tomato bacterial canker, is the most notorious species of the genus. Yet, its origin and natural reservoirs remain elusive, and its populations show pathogenicity profiles with unpredictable plant disease outcomes. Here, we generate and analyse a decade-long genomic dataset of Clavibacter from wild and commercial tomato cultivars, providing evolutionary insights that directed phenotypic characterization. Our phylogeny situates the last common ancestor of C. michiganensis next to Clavibacter isolates from grasses rather than to the sole strain we could isolate from wild tomatoes. Pathogenicity profiling of C. michiganensis isolates, together with C. phaseoli and C. californiensis as sister taxa and the wild tomato strain, was found to be congruent with the proposed phylogenetic relationships. We then identified gene enrichment after the evolutionary event, leading to the appearance of the C. michiganesis clade, including known pathogenicity factors but also hitherto unnoticed genes with the ability to encode adaptive traits for a pathogenic lifestyle. The holistic perspective provided by our evolutionary analyses hints towards a host shift event as the origin of C. michiganensis as a tomato pathogen and the existence of pathogenic genes that remain to be characterized.

Targeted isolation of extracellular vesicles from cell culture supernatant using immuno-affinity chromatography

Extracellular vesicles (EVs) have emerged as promising therapeutics with broad clinical applications as diagnostic biomarkers and therapeutic drug delivery systems. Yet, these biopharmaceuticals pose a challenge in terms of manufacturing due to their complexity and heterogeneity. Despite advancements in the field, current purification technologies lack scalability and/or selectivity. Affinity chromatography (AC) − coupling unmatched specificity and scalability − could be used to simplify purification processing and generate clinical-grade EVs with higher titers and purity.In the present work, we report the implementation of an immuno-AC resin to capture and purify EVs directly from clarified cellular feedstocks. Firstly, to guide and support marker selection, vesicle phenotype characterization was conducted using single particle interferometric reflectance image sensing (SP-IRIS) coupled with immunofluorescence. CD81 was the marker which shown to be more present and more likely to have the other markers (CD63 and CD9). Thus, anti-CD81 VHH ligand was generated and evaluated towards recombinant CD81 protein and CD81 bearing EV particles using surface plasmon resonance (SPR). Different chromatographic studies with Anti-CD81 ligand immobilized onto agarose beads resin were conducted to optimize the process parameters (residence time, dynamic binding capacity and impurity clearance). At residence time of 2 min, on average 40 % of pure triple tetraspanin-positive EV fraction was recovered. The enrichment in EV particles herein obtained, based on scale-up calculations, it would be possible to produce 1 × 1013 EVs from a 1L cell culture, while meeting impurity requirements in a single-step purification process (impurity removal over 2 log reduction value). A single-step purification process is possible, enabling the successful isolation of homogeneous EVs population, counting with a final HCP titer of 60 ng/mL and 9 ng/mL of dsDNA impurities. EV’s morphological integrity and internalization ability were also demonstrated, showcasing elution’s efficiency under mild conditions.Overall, this work contributes to the development of a novel, highly specific, AC technology using a camelid-derived affinity ligand which, bridging the scalability requirements demanded of large-scale production, could potentiate the advent of EV-based therapies.

The peritumoral edema index and related mechanisms influence the prognosis of GBM patients

BackgroundPeritumoral brain edema (PTBE) represents a characteristic phenotype of intracranial gliomas. However, there is a lack of consensus regarding the prognosis and mechanism of PTBE. In this study, clinical imaging data, along with publicly available imaging data, were utilized to assess the prognosis of PTBE in glioblastoma (GBM) patients, and the associated mechanisms were preliminarily analyzed.MethodsWe investigated relevant imaging features, including edema, in GBM patients using ITK-SNAP imaging segmentation software. Risk factors affecting progression-free survival (PFS) and overall survival (OS) were assessed using a Cox proportional hazard regression model. In addition, the impact of PTBE on PFS and OS was analyzed in clinical GBM patients using the Kaplan–Meier survival analysis method, and the results further validated by combining data from The Cancer Imaging Archive (TCIA) and The Cancer Genome Atlas (TCGA). Finally, functional enrichment analysis based on TCIA and TCGA datasets identified several pathways potentially involved in the mechanism of edema formation.ResultsThis study included a total of 32 clinical GBM patients and 132 GBM patients from public databases. Univariate and multivariate analyses indicated that age and edema index (EI) are independent risk factors for PFS, but not for OS. Kaplan–Meier curves revealed consistent survival analysis results between IE groups among both clinical patients and TCIA and TCGA patients, suggesting a significant effect of PTBE on PFS but not on OS. Furthermore, functional enrichment analysis predicted the involvement of several pathways related mainly to cellular bioenergetics and vasculogenic processes in the mechanism of PTBE formation. While these novel results warrant confirmation in a larger patient cohort, they support good prognostic value for PTBE assessment in GBM.ConclusionsOur results indicate that a low EI positively impacts disease control in GBM patients, but this does not entirely translate into an improvement in OS. Multiple genes, signaling pathways, and biological processes may contribute to the formation of peritumoral edema in GBM through cytotoxic and vascular mechanisms.

Hereditary transthyretin amyloidosis caused by Val142Ile variant in Spain: phenotypic characteristics, geographic distribution and population frequency

Abstract Background During recent years, several cases of hereditary transthyretin amyloidosis (ATTRv) due to p.Val142Ile have been described in patients without African ancestry in countries like Japan, Spain or Italy (1,2,3,4). All this evidence suggests that p.Val142Ile might be more prevalent than expected worldwide. Objectives The aim of this study was to analyze the impact of ATTRv caused p.Val142Ile in Spain to define its phenotypic characteristics, to explore endemic geographical areas and define its population frequency. Methods Patients diagnosed with ATTRv caused by p.Val142Ile and carriers irrespective of their phenotype were recruited from 16 centers in Spain. Baseline characteristics and events during follow-up were retrieved. Population frequency was assessed through the Spanish National DNA bank (N=3,569) and the Catalan Health Databank (N=790). Results The cohort included information regarding 164 subjects (75 probands [45.7%] and 89 relatives [54.3%]). Among probands, mean age was 73.9 ± 8.5 years and 47 (62.7%) were males. 67 probands (89.3%) had self-declared European ancestry and only 6 cases (8%) referred African or Afro-American ancestry. Cardiac symptoms were the most frequent reason leading to ATTRv diagnosis (N=64, 85.3%) followed by incidental finding (N=8, 10.7%) and neurologic symptoms (N=3, 4%). (Figure 1). Median follow-up was 1.6 years (Interquartile range 0.6-3.2). Neurologic involvement was observed in 35 probands (46.7%) at first evaluation or during follow-up. Overall penetrance at 65, 75 and 85 years was 12.8%, 44.3% and 94.2% respectively. Male sex was associated with earlier penetrance than women (P = 0.02). 38 patients initiated treatment with tafamidis during follow-up (28 [73.7%] 20 mg and 10 [26.3%] 61 mg), despite treatment, disease progression at 1 year (cardiovascular death or 30% increase of NTProBNP) was observed in 10 patients (40%). Population frequency was estimated between 0.0% and 0.12% based on the Spanish and Catalan databases respectively. Birthplace of probands suggests a higher prevalence in the Mediterranean basin. (Figure 2) Conclusions Our data suggests that ATTRv caused by p.Val142Ile has a significant prevalence in Spain, mostly in some specific regions. Phenotypic features are defined by late onset, male predominance, and cardiac involvement although a significant proportion develop neuropathy. Disease progression was observed in 40% of patients despite disease-modifying therapies.

Left atrial morpho-functional parameters and their correlation with other phenotypic and functional characteristics of hypertrophic cardiomyopathy

Abstract Background Left atrial (LA) volume index (LAVI), LA reservoir strain (LARS) and total atrial conduction time (TACT) (estimated by tissue Doppler imaging) are morphological and functional parameters reflecting LA structural and electrical remodeling, connected to atrial fibrillation development and heart failure progression in various substrates. In hypertrophic cardiomyopathy (HCM), correlation of the above-mentioned parameters with other disease characteristics is not fully investigated. Purpose Aim of this study was to estimate the prevalence of atrial myopathy characteristics such as increased LAVI, impaired LARS and elongated TACT in a cohort of HCM patients without AF history and investigate their correlation with other phenotypic and functional characteristics of the disease such as left ventricular (LV) hypertrophy magnitude, fibrosis extent and diastolic dysfunction grade. Methods We included 100 HCM patients (54±21 years, 75% male, maximum wall thickness 19±3.4mm) without history of atrial fibrillation who have consecutively undergone 2D-speckle tracking echocardiography and cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE). TACT and LARS measurement is shown on left panel. Burden of fibrosis (percentage of LV mass) was defined by LGE extent (>5 standard deviations compared to nulled myocardium) in CMR slices. Results All HCM patients had preserved EF (60±7.5%), while 28 (28%) presented outflow tract obstruction and 10 (10%) diastolic dysfunction stage≥2. LGE was observed in 64 patients (64%) occupying 8±5% of left ventricular (LV) mass. Mean TACT was 140±22 msec, with LAVI being 32±16 mL/m2 and LARS 26±14%. Among HCM demographic, phenotypic and functional characteristics tested, age and LV mass index were found to be the only independent regressors of TACT (r=0.54, p<0.0005 and r=0.44, p=0.002 respectively, right upper panel), while E/E’ (r=-0.44, p=0.003) and fibrosis extent (r=0.36, p=0.02) were the strongest predictors of LARS and LAVI values respectively (right lower panel). Conclusions Atrial myopathy parameters seem to correlate with various morphological and functional characteristics of HCM. Atrial electro-mechanical delay assessed through TDI based TACT correlates significantly with LVMI, whereas LARS and LAVI are strong regressors of elasticity properties, partially expressed through diastolic function and underlying fibrosis.

A Homoplasmic MT-TV Mutation Associated with Mitochondrial Inheritance of Hereditary Spastic Paraplegia.

Hereditary spastic paraplegia (HSP) is characterized by progressive lower limb weakness and spasticity, with unknown genetic cause in many cases. To identify novel genetic causes of HSP. Phenotypic characterization, genetic screening, transcriptome sequencing, and peroneal nerve biopsy were conducted in a Chinese HSP family. We found a homoplasmic MT-TV (mitochondrial tRNAVal) mutation, m.1661A > G, present in all affected individuals across four generations of a family with complex HSP. Fourth-generation affected individuals displayed earlier onset, likely due to presumptive anticipation, and greater symptom severity, potentially caused by decreased mitochondrial DNA (mtDNA) copy number. Upregulation of mitochondrial autophagy genes in these patients suggested that MT-TV mutations could lead to reduced mtDNA copy number. Neural biopsies revealed ultrastructural abnormalities in myelin and mitochondria. The rare MT-TV m.1661A > G mutation is associated with HSP. Variations in mtDNA copy number may play a causal role in differences among clinical phenotypes. © 2024 International Parkinson and Movement Disorder Society.

Identification of new phenotypes in type 2 diabetes with acute myocardial infarction: toward a precision medicine?

Abstract Background Type 2 diabetes mellitus (T2DM) is a highly heterogeneous entity, with multiple subgroups differing by clinic presentation, disease progression and risk of complications such as myocardial infarction (MI). A new T2DM phenotyping classification has been recently proposed to help to improve treatment tailoring and target early treatments, and we aimed to identify the prevalence and characteristics of the new phenotypes. Methods All consecutive adults with a history T2DM hospitalized in a french Coronary Intensive Care Unit for an acute MI between February 1st, 2021 and January 31st, 2023 were included. Clusters were based on six variables (glutamate decarboxylase antibodies, age at diagnosis, BMI, HbA1c, and homoeostatic model assessment 2 estimates of β-cell function and insulin resistance). We stratified patients into five subgroups : 1/ SAID=severe autoimmune diabetes; 2/ SIDD=severe insulin-deficient diabetes; 3/ SIRD=severe insulin-resistant diabetes; 4/ MOD=mild obesity-related diabetes; and 5/ MARD=mild age-related diabetes. Results Among the 266 patients included, characteristics according to diabetes phenotypes are summarized in the Table. Conclusions Our prospective study showed that in real-world T2DM patients with acute MI, unclassical phenotypes, i.e. hyperinsulinaemic and insulinopaenic were common. Given the large discrepancies in characteristics, our findings suggest the relevance of the new substratification. However, its clinical utlity and translation in tailored treatment strategies and prognosis remains to be determined.Table.

Safety, acceptability, and feasibility of acquiring endothelial cells from guidewires in patients having major surgery or with acute critical illness

Abstract Background Endothelial cells (EC) play a key role in vascular homeostasis, and endothelial dysfunction has been linked to the development of cardiovascular disease. While most EC research relies on indirect assessment of EC function in humans, in vitro systems and in vivo animal models, the development of a safe protocol to isolate EC from patients would provide a new window into EC function. Purpose To assess (a) the feasibility of isolating EC from discarded guidewires used as part of the standard of care (SOC) in surgical patients and patients admitted to intensive care (ICU) and (b) to compare EC phenotypes in the patient cohorts. Methods Discarded guidewires were collected from arterial lines and central venous catheters (CVC) from 15 patients before abdominal surgery and 16 patients admitted to ICU requiring organ support. Additionally, J-wires were inserted into forearm veins using an proven technique for EC biopsy (ECBx) in all surgical patients. ECs were dissociated from guidewires, stained for CD31, CD144, CD202b, and nuclear integrity then analysed using flow-cytometry. EC were characterised based on surface marker expression and granularity. Blood biomarkers and clinical information was collected. Organ function was assessed using sequential organ failure assessment (SOFA). Tolerability and adverse event (AE) data was also collected using structured interviews to support the analysis. Results From the surgical cohort 6 arterial lines, 14 CVC and 15 ECBx were collected. From the ICU patients, 8 arterial lines and 9 CVC were collected. EC were identified as live and triple positive for CD31, CD144, CD202b. A median of 536 (IQR 160-796 ) EC were obtained from arterial lines, 622 (IQR 329-1045) from CVCs and 768 (IQR 210-1001) from ECBx with no significant difference between method of collection (Kruskal-Wallis p>0.05). Median granularity showed a significant increase in granularity in EC collected from ICU patients compared to the surgical patients. This could be attributed to internalisation of cell surface proteins or apoptosis caused by the hyperinflammatory conditions in ICU patients (SOFA 7, IQR 5-8.25, CRP 118, IQR 66.2-298) when compared to the surgical patients (SOFA 1, IQR 0-2, CRP <4mg/l). Median fluorescent intensity analysis of all three markers did not show a significant difference between patient groups. AEs to ECBx reported only 4 patients experienced light bruising. High tolerability was reported for ECBx by structured interview, with patients agreeing that they theoretically would tolerate up to 3 ECBx. Conclusion(s) It is feasible to isolate ECs from patients during SOC using discarded guidewires. As an isolated procedure, ECBx from forearm veins is well tolerated and carries low risk. This enables the characterisation of EC phenotypes and obtain unique insight in their roles in health and disease.

Genotype-phenotype relationship in hypertrophic cardiomyopathy

Abstract Background/Introduction Hypertrophic cardiomyopathy (HCM) is an inherited highly heterogeneous disease with variable penetrance and expression, but the exact relationship between the underlying genetic cause and the clinical course remains elusive. Purpose The aim of our study was to analyse the phenotypic and molecular characteristics of individuals with HCM examined and treated at our University Hospital. Methods Clinical data from adult HCM patients treated at our hospital between 2005 and 2023 were analysed. Informed consents to participate in the study were obtained from all participants. Clinical manifestation, instrumental examination and next generation sequencing (NGS) data of HCM related genes were collected. The Mann–Whitney U for two groups and Kruskal–Wallis tests for more than two groups were used to compare continuous variables. Univariate logistic regression was used to analyze categorical variables. Results The study involved 191 unrelated individuals, 58.6% males, the median age at HCM diagnosis was 50, interquartile range 37 – 60 years. A median follow-up was 3.9 [1.6-6.4] years. Pathogenic and likely pathogenic (P/LP) variants were identified in 45.5% (N=87) of affected individuals. Truncating variants were observed in 31 individuals. MYBPC3 P/LP variants were the most common (N=47), following by MYH7 (N=22) and other (N=18). Individuals with MYBPC3 P/LP truncating variants had higher HCM estimated 5-year risk of sudden cardiac death (SCD) during primary evaluation (3.1 [2.5-4.6]) compared to individuals with P/LP variants in other genes (2.4 [1.9-3.7]) and individuals with negative NGS results (1.8 [1.5-2.7], p<0,001). Patients with MYBPC3 P/LP variants experienced the earliest onset of symptoms (median age 37.0 [30.5-50.0] years) and HCM diagnosis (median age 38.0 [31.0-51.5] years) compared to individuals with other genes P/LP variants (median age 46.0 [31.0-56.2] years and 47.5 [31.5 – 59.5] years, respectively) and genotype negative individuals (median age 51.5 [44.0-61.0] years and 52.0 [45.0-63.2] years, respectively), p>0,001). The presence of P/LP variant was associated with significantly thicker left ventricular wall (maximal thickness) on cardiac imaging in comparison with negative NGS results (18.0 [15.0-21.0] mm vs. 16.0 [14.0-18.0] mm, p=0.002 on transthoracic echocardiography and 20.0 [17.0-22.5] mm vs. 18.0 [16.0-20.0] mm, p<0,001 on cardiac magnetic resonance). The presence of MYBPC3 truncating variants were associated with the greatest risk of ventricular tachycardia in comparison with negative NGS results (OR 3.05, 95% CI:1.3, 8.0, p=0.025). Conclusion More severe HCM phenotype is associated with detection of P/LP variants in HCM related genes. The presence of the MYBPC3 P/LP variant is associated with an earlier onset of the disease and truncating variants of this gene are related to a higher risk for ventricular tachycardia and an estimated 5-year risk of SCD.

Phenotypic and clinical evaluation of hypertrophic cardiomyopathy caused by the deep intronic variant MYBPC3:c.2308+227G>A

Abstract Introduction Deep intronic variants can be the cause of hypertrophic cardiomyopathy (HCM), although these regions of the genome are not always sequenced in genetic studies. It is unknown if there are differences in phenotypic expressivity and prognosis compared to other forms of HCM. Objective to describe the phenotypic and clinical characteristics of a cohort of probands with HCM due to the variant MYBPC3:c.2308+227G>A and compare whether there are differences with other HCM groups. Methods Retrospective observational study of the clinical and imaging data of patients with HCM evaluated in a reference center for Inherited Cardiovascular Disease. Probands carrying the MYBPC3:c.2308+227G>A variant, other pathogenic or likely pathogenic variants in MYBPC3 and those with a negative genotype (NGS sequencing) were included. Results 151 probands with HCM (70% males; age of diagnosis 56±14) were included, 26 carrying MYBPC3:c.2308+227G>A (figure). No significant differences were found between the three groups in terms of baseline characteristics, phenotypic features or risk profile. In the survival curves, the subgroup with the variant had a earlier tendency to events, particularly for heart failure (figure). Conclusions HCM associated with MYBPC3:c.2308+227G>A variant does not have differential characteristics in its phenotypic and clinical expression, having a similar prognosis to other HCM in our cohort.

Comparison of mitral valve apparatus anomalies between sarcomeric hypertrophic cardiomyopathy and Fabry disease cardiomyopathy

Abstract Background Despite different etiopathogenesis, Fabry disease (FD) cardiomyopathy and sarcomeric hypertrophic cardiomyopathy (HCM) share a similar hypertrophic phenotype. Cardiac magnetic resonance (CMR) plays a pivotal role in distinguishing between these two clinical conditions, thanks to the thorough morphological definition of the phenotype and non-invasive tissue characterization. A high prevalence of mitral apparatus anomalies has been previously described both in sarcomeric HCM and FD cardiomyopathy. Purpose This study systematically compares the morphology of the mitral apparatus in sarcomeric HCM and FD cardiomyopathy, to add new insights into differential diagnosis. Methods CMR images of 120 patients were retrospectively analyzed and divided as follows: healthy controls CTRL (n=40), HCM (n=40), and FD (n=40) with left ventricular hypertrophy (LVH). The analyses included the measurement of I) papillary muscles’ hypertrophy, expressed as the maximum diameter (D max) of the anterolateral (AL) and posteromedial (PM) papillary muscles (see Figure 1 A and B); II) the anteriorization of the anterolateral papillary muscle defined as the distance between the anterolateral papillary muscle and the anterior interventricular junction (Anteriorization of AL) (Fig. 1 C); III) the length of the anterior mitral leaflet (MVL length) (Fig. 1 D). All measurements were performed on cine-SSFP sequences in diastole. Results Compared to healthy controls, HCM and FD patients showed significant hypertrophy of both papillary muscles (p<0.001) and elongation of the anterior mitral leaflet (p<0.001). Both papillary muscles in FD patients showed greater hypertrophy compared to HCM patients (D max AL p=0.017 and D max PM p=0.039). No significant differences were observed between FD and HCM regarding MVL length (p=0.078). Compared to FD (p=0.028) and healthy controls (p<0.001), HCM patients showed greater anteriorization of the anterolateral papillary muscle. (Results are summarized in Table 1). Conclusions From the comparison of mitral valve apparatus anomalies between HCM and FD, it emerged that patients with FD cardiomyopathy show a higher degree of papillary muscle hypertrophy, while patients with sarcomeric HCM display a greater anterior displacement of the anterolateral papillary muscle. The systematic analysis of the morphology of mitral apparatus can be integrated in the differential diagnosis between these two pathologies.Fig.1 Representation of MeasurementsTable 1.Summary results table

CMR phenotypes and clinical outcomes in NYHA class I versus II-IV hypertrophic cardiomyopathy: identifying high-risk asymptomatic patients

Abstract Background Cardiac myosin inhibition therapy can deliver symptomatic benefit for NYHA class≥II patients with obstructive hypertrophic cardiomyopathy (HCM) and is being actively explored for non-obstructive phenotypes. However, expanding interest in clinical outcome reduction supports growing need to identify high risk cohorts across both symptomatic and asymptomatic cohorts. We aimed to examine phenotypic characteristics of NYHA-I versus NYHA≥II patients with HCM and their association with future outcomes. Methods 727 patients with HCM from the CIROC Registry who completed simultaneous CMR and patient health assessments, inclusive of NYHA evaluation and quality of life surveys, were studied. Baseline clinical and CMR characteristics were compared between NYHA-I and NYHA≥II cohorts, followed by risk modelling for the prediction of major adverse cardiovascular events (MACE), defined as: all-cause mortality, heart failure hospitalization, ventricular arrhythmia, new onset atrial fibrillation, or stroke. Cox models were constructed to identify independent predictors of MACE. Results Of the 727 patients, 546 (75%) reported NYHA-I and 181 (25%) NYHA≥II symptoms. Baseline characteristics are shown in Table 1. Compared to NYHA≥II, NYHA-I patients were younger, more likely male, and had a lower prevalence of diabetes and hypertension. No meaningful differences in CMR chamber volumes, function, left ventricular (LV) mass, or fibrosis burden were observed. Over a median follow up of 3.7 years, 109 patients (15%) experienced MACE: 12% in NYHA-I and 23% in NYHA≥II sub-groups (p<0.001). Baseline LV mass z-scores (determined from sex-matched, BSA-indexed SCMR healthy reference values) were independently associated with MACE by multivariable Cox modelling. An optimal LV mass z-score threshold of 3.9 for prediction of MACE was identified and combined with NYHA status to stratify patients into 4 categories. Kaplan-Meier curves showed patients with LV Mass z-scores >3.9 experienced worse event-free survival in both NYHA sub-groups (Figure 1a). Cox modelling in the overall cohort (Figure 1b) showed NYHA-I patients with LV Mass z-scores >3.9 experienced a 2.2-fold increased risk (p=0.007) of MACE, this exceeding the risk of NYHA ≥II patients below this threshold. Separate NYHA I and ≥II sub-group multivariable models showed LV Mass z-score >3.9 to remain a strong and independent predictor of MACE, providing respective hazards of 2.6 and 4.7 (p=0.001 and <0.001). Conclusions NYHA-I patients with HCM experience significantly lower rates of MACE versus NYHA≥II. However, LV mass z-scoring permits powerful sub-stratification of these sub-groups, identifying NYHA-I patients with higher LV mass who will experience worse outcomes versus NYHA≥II patients with lower LV mass. This simple yet powerful stratification offers unique potential to identify asymptomatic patients with HCM who may benefit from targeted therapeutics to reduce future MACE.

Intra-specific variations in Schistosoma mansoni and their possible contribution to inconsistent virulence and diverse clinical outcomes.

Schistosoma mansoni was introduced from Africa to the Americas during the transatlantic slave trade and remains a major public health problem in parts of South America and the Caribbean. This study presents a comprehensive comparative analysis of three S. mansoni strains with different geographical origins-from Liberia, Belo Horizonte and Puerto Rico. We demonstrated significant variation in virulence and host-parasite interactions. We investigated the phenotypic characteristics of the parasite and its eggs, as well as the immunopathologic effects on laboratory mouse organ systems. Our results show significant differences in worm morphology, worm burden, egg size, and pathologic organ changes between these strains. The Puerto Rican strain showed the highest virulence, as evidenced by marked liver and spleen changes and advanced liver fibrosis indicated by increased collagen content. In contrast, the strains from Liberia and Belo Horizonte had a less pathogenic profile with less liver fibrosis. We found further variations in granuloma formation, cytokine expression and T-cell dynamics, indicating different immune responses. Our study emphasizes the importance of considering intra-specific variations of S. mansoni for the development of targeted therapies and public health strategies. The different virulence patterns, host immune responses and organ pathologies observed in these strains provide important insights for future research and could inform region-specific interventions for schistosomiasis control.

Moderate intensity exercise training ameliorates the heart failure with preserved ejection fraction phenotype in a preclinical model by improving cardiometabolic fitness

Abstract Introduction and Aim Exercise intolerance is a hallmark feature of patients with heart failure with preserved ejection fraction (HFpEF).While clinical evidence suggests potential benefits of exercise training in HFpEF, its mechanisms remain largely unknown.In this study, we used a translationally relevant murine model of cardiometabolic HFpEF(1) to assess whether moderate intensity continuous training(MICT) can ameliorate the HFpEF phenotype in mice and promote cardiometabolic health. Methods Twenty-five adult, male C57BL/6N were fed with the combination of high fat diet(HFD;D12492,Research diet)and L-NAME(0.5 g/L,in drinking water) for 15 weeks to elicit HFpEF as previously described(1).After the establishment of the HFpEF phenotype, mice were randomized in two groups:sedentary(SED,n= 10) and exercised(MICT,n=15)mice.MICT was carried out according to the protocol:running on 10-degree positive inclination treadmill for 8 consecutive weeks,5 times/week,60 minutes/day,at a speed gradually increasing from 0.1 to 0.2 m/sec on a weekly basis.Morphometry, echocardiography(TTE),isoproterenol-induced stress echocardiography(SE),time domain nuclear magnetic resonance, and treadmill exhaustion tests were performed at the beginning and end of MICT.Additionally, at the end of MICT blood and tissues were collected for proteomics analysis(Fig1).Non-trained male C57BL/6N mice(37w) were used as controls for the HFpEF mice. Results Before randomization, all HFpEF mice were similar in terms of phenotypic characteristics. Compared to SED mice, MICT induced a significantly decrease in body weight driven by a reduction of total fat mass with an increased in lean mass(Fig2A+B).Interestingly, MICT had no impact on skeletal muscle mass for all different muscle groups evaluated (extensor digitorum longus, soleus and tibialis anterior).Importantly, MICT led to a significant improvement in exercise capacity in HFpEF mice, as shown by increased running distance and time, surpassing even the running distance seen in non-HFpEF mice (SED:62.8±18.7,MICT:305.7±13.9,non-HFpEF mice: 129.72±15.2meters,p<0.001).Preclinical surrogate of HFpEF such as pulmonary congestion, evaluated by index lung weights, improved after aerobic training.Following MICT there was a marked improvement in diastolic dysfunction(measured by E/E’ratio) both at rest(SED:36.5±3.3,MICT:23.3±5.09,p<0.001) and after isoproterenol challenge(SED:42.6±15.1,MICT:26.09±3.75,p<0.001)(Fig2C).Moreover, the wet cardiac mass was lower in the MICT group(Fig2A), suggesting potential amelioration in cardiac hypertrophy following aerobic training. Conclusion Eight weeks of supervised MICT on treadmill improves functional status, exercise capacity, and diastolic function in a cardiometabolic HFpEF murine model.The most significant effects were seen on weight loss and fat mass reduction.Our findings suggest a beneficial impact of aerobic exercise in mitigating HFpEF by improving metabolic fitness in the preclinical HFpEF model.Fig1-Study DesignFig2-Characteristics SED vs MICT groups

Single-cell mass cytometry analysis unveils prothrombotic expression and heterogeneity in essential thrombocythemia

Abstract Background/Introduction Essential thrombocythemia (ET) is recognized for its hallmark elevated platelet count and a consequent increased risk of thromboembolic events including coronary events. Despite its clinical significance, the pathophysiological mechanisms predisposing ET patients to thrombosis remain largely undefined. Purpose The aim of this pioneering study was to shed light on the increased thrombotic risk in ET by conducting a detailed phenotypical characterization of platelet expression using single-cell mass cytometry, comparing ET patients to age- and sex-matched healthy controls. Methods Platelet samples from six patients diagnosed with ET and six healthy individuals were analyzed. This analysis utilized an extensive panel of 18 transmembrane regulators pivotal for platelet function and activation. Measurements were taken both at baseline and after ex-vivo stimulation with thrombin receptor-activating peptide (TRAP). Advanced clustering analysis via the FlowSOM algorithm helped identify specific subclusters of platelets with a prothrombotic expression profile. Results Our investigation revealed a significant overexpression of the activation marker CD62P (P-Selectin, p=0.049) and of the collagen receptor GPVI (p=0.044) in non-stimulated ET platelets (Figure 1A-C). Conversely, a notable decrease in expression was observed for the fibrinogen receptor GPIIb/IIIa units CD41 (p=0.036) and CD61 (p=0.044), as well as for the von Willebrand factor receptor CD42b (p=0.044). The FlowSOM analysis distinguished two prothrombotic subclusters of ET platelets, particularly highlighting one cluster, which was significantly overrepresented in ET (22.13% of total ET platelets versus 2.94% in controls, p=0.035, Figure 1D-E). Conclusion This study presents compelling evidence of a distinct prothrombotic phenotype in ET, marked by significant alterations in platelet expression profiles. The overexpression of CD62P and GPVI, alongside the underexpression of CD41, CD61, and CD42b, underscores the complex pathophysiological landscape of ET. Importantly, we identified a specific subcluster, particularly overrepresented in ET, with a specific prothrombic signature. Our findings, while only hypothesis generating, propose GPVI as a potential therapeutic target to mitigate thrombosis in ET patients, paving the way for targeted interventions in this high-risk population.

Mechanical right ventricular involvement is independent of right coronary arterial bed and has a prognostic impact in acute myocardial infarction complicated by cardiogenic shock

Abstract Background In Acute Myocardial Infarction complicated by Cardiogenic Shock(AMI-CS), understanding the implications of right ventricular involvement (RVi) is crucial for refining risk stratification and optimizing management. Purpose Distinguish the prognosis in RVi at baseline(RVB) and persistent(RVP) in AMI-CS Methods 357 patients with AMI-CS+PAC serial measures at 0, 6, 12, 24h. RVi was defined as the presence of all 4 criteria PAPI<1; RVSWi≤4.08; RAP≥15 mmHg; and PVC/PCP≥0.86 and persistent as the presence of the 4 criteria at 4 time points. For hemodynamic measures, repeated measures ANOVA; and KM curves and Cox regression were performed. Results 300 without vs 57 with RVB. Additionally, 344 without vs 13 had RVP. Killip-Kimball classification showed a higher significant association with both RVB(P=0.042). A higher percentage of RVB received vasopressin(P=0.008), and there was a significant association with levosimendan use(P=0.009) in RVP. The higher MODS score, RVB(P=0.017) and RVP(P=0.029). The number of vasoactives was higher in RVB(P=0.031) RVP(P=0.009). Finally, the phenotypic characterization revealed a significant association with RVB(P=0.001) and RVP(P=0.032) more cardio-metabolic. The SCAI-CSWG classification indicated a higher proportion in the E category for both RVB(P=0.046) and not significant in RVP(P=0.405). Overall, mortality rates did not differ significantly between in RVB(P=0.174) or RVP(P=0.117), although there was a trend towards higher mortality in patients with RVi. Age, sex, DM, HTN, previous MI, PCI, CABG, stroke, and type of MI, primary reperfusion, LVEF, and laboratory parameters did not differ. RVB had higher heart rate(P=0.036), RAP, PASP(both P<0.001), lower SBP(P=0.049), cardiac output(P=0.004), index(P=0.001), power(P=0.012), power index(P=0.002), CPI(RAP), perfusion pressure, PAPi(both P<0.001), Stroke volume(SV, P=0.001), SVi(P<0.001), LVSWi(P=0.001), and RVSWi(P<0.001). RVP higher RAP(<0.001), and lower cardiac output(P=0.008), index(P=0.005), power(P=0.034), power index(P=0.029), CPI(RAP)(P=0.002), perfusion pressure(P=0.035), PAPi(P<0.001), SV(P=0.018), SVi(P=0.011), LVSWi(P=0.034) RVSWi(P<0.001). Importantly interaction between group*time was found in RVB in RAP(P<0.001), mPAP(P=0.038), perfusion pressure(P=0.002) and RVSWi(P<0.001) and in RVP in SV(P=0.014), SVi(P=0.013) and LVSWi(P=0.028) suggest that RVi had different hemodynamic response. For RVB a reduction of -4.16 days in survival time (-7.79, -0.54, P=0.024); Logrank P=0.035. Similarly, for RVP demonstrated a significant reduction of -7.27 days (-14.08, -0.47, P=0.036); Logrank P=0.017. No significant of the culprit artery in RVB, RVP (P>0.05) was observed. RVB and RVP was strongly associated with a higher prevalence of RVi (STe-V3/4R) on ECG (35.1 vs. 11.7%, and 61.5 vs. 13.7%, P<0.001). Conclusion In AMI-CS, RVi, whether baseline or persistent, is associated with distinct hemodynamic profiles and a trend toward higher mortality.Figure 1.Hemodynamics of RVB(A-C) & RVP(D-F)Figure 2.Survival of RVB, RVP (A, B) & HR(C)