Circulating long noncoding RNA PDE4DIPP6: A novel biomarker for improving the clinical management of non-ST-segment elevation myocardial infarction.

BACKGROUND: Long noncoding RNAs (lncRNAs) have emerged as promising diagnostic biomarkers. Here, we investigated the cardiac-expressed and plasma-detectable lncRNA PDE4DIPP6 as a biomarker for non-ST-segment elevation myocardial infarction (NSTEMI), specifically assessing its potential to enhance the diagnostic efficacy of high-sensitivity cardiac troponin (hs-cTnT). METHODS AND RESULTS: The study enrolled individuals presenting with suspected acute coronary syndrome (ACS). LncRNA quantification was performed in plasma samples using RT-qPCR. The discriminatory performance was assessed by calculating the Area Under the Curve (AUC). Reclassification metrics, including the Integrated Discrimination Improvement (IDI) and Net Reclassification Improvement (NRI) indexes, were utilized to evaluate enhancements in diagnostic accuracy. Among the 252 patients with suspected ACS, 50.8 % were diagnosed with ACS, and 13.9 % with NSTEMI. Initially, the association of lncRNA PDE4DIPP6 with ACS was investigated. Elevated levels of this lncRNA were observed in ACS patients compared to non-ACS subjects. No association was found between lncRNA PDE4DIPP6 levels and potential confounding factors, nor was a significant correlation with hs-cTnT levels (rho = 0.071). The inclusion of lncRNA PDE4DIPP6 on top of hs-cTnT significantly improved the discrimination and classification of ACS patients, as reflected by an enhanced AUC of 0.734, an IDI of 0.066 and NRI of 0.471. Subsequently, the lncRNA PDE4DIPP6 was evaluated as biomarker of NSTEMI. Elevated levels of the lncRNA were observed in NSTEMI patients compared to patients without NSTEMI. Consistent with previous findings, the addition of lncRNA PDE4DIPP6 to hs-cTnT improved the discrimination and classification of patients, increasing the AUC from 0.859 to 0.944, with an IDI of 0.237 and NRI of 0.658. CONCLUSION: LncRNA PDE4DIPP6 offers additional diagnostic insights beyond hs-cTnT, suggesting its potential to improve the clinical management of patients with NSTEMI.

Right heart failure with left ventricular assist devices: Preoperative, perioperative and postoperative management strategies. A clinical consensus statement of the Heart Failure Association (HFA) of the ESC.

Right heart failure (RHF) following implantation of a left ventricular assist device (LVAD) is a common and potentially serious condition with a wide spectrum of clinical presentations with an unfavourable effect on patient outcomes. Clinical scores that predict the occurrence of right ventricular (RV) failure have included multiple clinical, biochemical, imaging and haemodynamic parameters. However, unless the right ventricle is overtly dysfunctional with end-organ involvement, prediction of RHF post-LVAD implantation is, in most cases, difficult and inaccurate. For these reasons optimization of RV function in every patient is a reasonable practice aiming at preparing the right ventricle for a new and challenging haemodynamic environment after LVAD implantation. To this end, the institution of diuretics, inotropes and even temporary mechanical circulatory support may improve RV function, thereby preparing it for a better adaptation post-LVAD implantation. Furthermore, meticulous management of patients during the perioperative and immediate postoperative period should facilitate identification of RV failure refractory to medication. When RHF occurs late during chronic LVAD support, this is associated with worse long-term outcomes. Careful monitoring of RV function and characterization of the origination deficit should therefore continue throughout the patient's entire follow-up. Despite the useful information provided by the echocardiogram with respect to RV function, right heart catheterization frequently offers additional support for the assessment and optimization of RV function in LVAD-supported patients. In any patient candidate for LVAD therapy, evaluation and treatment of RV function and failure should be assessed in a multidimensional and multidisciplinary manner.

Prevention and rehabilitation after heart transplantation: A clinical consensus statement of the European Association of Preventive Cardiology, Heart Failure Association of the ESC, and the European Cardio Thoracic Transplant Association, a section of ESOT.

Little is known either about either physical activity patterns, or other lifestyle-related prevention measures in heart transplantation (HTx) recipients. The history of HTx started more than 50 years ago but there are still no guidelines or position papers highlighting the features of prevention and rehabilitation after HTx. The aims of this scientific statement are (i) to explain the importance of prevention and rehabilitation after HTx, and (ii) to promote the factors (modifiable/non-modifiable) that should be addressed after HTx to improve patients' physical capacity, quality of life and survival. All HTx team members have their role to play in the care of these patients and multidisciplinary prevention and rehabilitation programmes designed for transplant recipients. HTx recipients are clearly not healthy disease-free subjects yet they also significantly differ from heart failure patients or those who are supported with mechanical circulatory support. Therefore, prevention and rehabilitation after HTx both need to be specifically tailored to this patient population and be multidisciplinary in nature. Prevention and rehabilitation programmes should be initiated early after HTx and continued during the entire post-transplant journey. This clinical consensus.

Prevention and rehabilitation after heart transplantation: A clinical consensus statement of the European Association of Preventive Cardiology, Heart Failure Association of the ESC, and the European Cardio Thoracic Transplant Association, a section of ESOT.

Little is known either about either physical activity patterns, or other lifestyle-related prevention measures in heart transplantation (HTx) recipients. The history of HTx started more than 50 years ago but there are still no guidelines or position papers highlighting the features of prevention and rehabilitation after HTx. The aims of this scientific statement are (i) to explain the importance of prevention and rehabilitation after HTx, and (ii) to promote the factors (modifiable/non-modifiable) that should be addressed after HTx to improve patients' physical capacity, quality of life and survival. All HTx team members have their role to play in the care of these patients and multidisciplinary prevention and rehabilitation programmes designed for transplant recipients. HTx recipients are clearly not healthy disease-free subjects yet they also significantly differ from heart failure patients or those who are supported with mechanical circulatory support. Therefore, prevention and rehabilitation after HTx both need to be specifically tailored to this patient population and be multidisciplinary in nature. Prevention and rehabilitation programmes should be initiated early after HTx and continued during the entire post-transplant journey. This clinical consensus statement focuses on the importance and the characteristics of prevention and rehabilitation designed for HTx recipients.

CRISPR/Cas9-based GLA knockout to generate the female Fabry disease human induced pluripotent stem cell line MHHi001-A-15.

The X-linked lysosomal storage disorder Fabry disease originates from GLA gene mutations causing α-galactosidase A enzyme deficiency. Here we generated the GLA knockout hiPSC line MHHi001-A-15 (GLA-KOhiPSC) as an in vitro Fabry disease model by targeting exon 2 of the GLA gene by CRISPR/Cas9 in the established control hiPSC line MHHi001-A. GLA-KOhiPSCs retained the expression of pluripotency markers, trilineage differentiation potential, as well as normal karyotype and stem cell morphology but lacked α-galactosidase A enzyme activity. The GLA-KOhiPSCs represent a potent resource to not only study the Fabry disease manifestation but also screen for novel treatment options.

Mechanisms of myocardial reverse remodelling and its clinical significance: A scientific statement of the ESC Working Group on Myocardial Function.

Cardiovascular disease (CVD) is the leading cause of morbimortality in Europe and worldwide. CVD imposes a heterogeneous spectrum of cardiac remodelling, depending on the insult nature, that is, pressure or volume overload, ischaemia, arrhythmias, infection, pathogenic gene variant, or cardiotoxicity. Moreover, the progression of CVD-induced remodelling is influenced by sex, age, genetic background and comorbidities, impacting patients' outcomes and prognosis. Cardiac reverse remodelling (RR) is defined as any normative improvement in cardiac geometry and function, driven by therapeutic interventions and rarely occurring spontaneously. While RR is the outcome desired for most CVD treatments, they often only slow/halt its progression or modify risk factors, calling for novel and more timely RR approaches. Interventions triggering RR depend on the myocardial insult and include drugs (renin-angiotensin-aldosterone system inhibitors, beta-blockers, diuretics and sodium-glucose cotransporter 2 inhibitors), devices (cardiac resynchronization therapy, ventricular assist devices), surgeries (valve replacement, coronary artery bypass graft), or physiological responses (deconditioning, postpartum). Subsequently, cardiac RR is inferred from the degree of normalization of left ventricular mass, ejection fraction and end-diastolic/end-systolic volumes, whose extent often correlates with patients' prognosis. However, strategies aimed at achieving sustained cardiac improvement, predictive models assessing the extent of RR, or even clinical endpoints that allow for distinguishing complete from incomplete RR or adverse remodelling objectively, remain limited and controversial. This scientific statement aims to define RR, clarify its underlying (patho)physiologic mechanisms and address (non)pharmacological options and promising strategies to promote RR, focusing on the left heart. We highlight the predictors of the extent of RR and review the prognostic significance/impact of incomplete RR/adverse remodelling. Lastly, we present an overview of RR animal models and potential future strategies under pre-clinical evaluation.

A roadmap for therapeutic discovery in pulmonary hypertension associated with left heart failure. A scientific statement of the Heart Failure Association (HFA) of the ESC and the ESC Working Group on Pulmonary Circulation & Right Ventricular Function.

Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced functional capacity and negatively affects right heart function, ultimately leading to a poor prognosis. There are no specific treatments for PH-LHF, despite the high number of drugs tested so far. This scientific document addresses the main knowledge gaps in PH-LHF with emphasis on pathophysiology and clinical trials. Key identified issues include better understanding of the role of pulmonary venous versus arteriolar remodelling, multidimensional phenotyping to recognize patient subgroups positioned to respond to different therapies, and conduct of rigorous pre-clinical studies combining small and large animal models. Advancements in these areas are expected to better inform the design of clinical trials and extend treatment options beyond those effective in pulmonary arterial hypertension. Enrichment strategies, endpoint assessments, and thorough haemodynamic studies, both at rest and during exercise, are proposed to play primary roles to optimize early-stage development of candidate therapies for PH-LHF.

Circular RNA circZFPM2 regulates cardiomyocyte hypertrophy and survival.

Hypertrophic cardiomyopathy (HCM) constitutes the most common genetic cardiac disorder. However, current pharmacotherapeutics are mainly symptomatic and only partially address underlying molecular mechanisms. Circular RNAs (circRNAs) are a recently discovered class of non-coding RNAs and emerged as specific and powerful regulators of cellular functions. By performing global circRNA-specific next generation sequencing in cardiac tissue of patients with hypertrophic cardiomyopathy compared to healthy donors, we identified circZFPM2 (hsa_circ_0003380). CircZFPM2, which derives from the ZFPM2 gene locus, is a highly conserved regulatory circRNA that is strongly induced in HCM tissue. In vitro loss-of-function experiments were performed in neonatal rat cardiomyocytes, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and HCM-patient-derived hiPSC-CMs. A knockdown of circZFPM2 was found to induce cardiomyocyte hypertrophy and compromise mitochondrial respiration, leading to an increased production of reactive oxygen species and apoptosis. In contrast, delivery of recombinant circZFPM2, packaged in lipid-nanoparticles or using AAV-based overexpression, rescued cardiomyocyte hypertrophic gene expression and promoted cell survival. Additionally, HCM-derived cardiac organoids exhibited improved contractility upon CM-specific overexpression of circZFPM2. Multi-Omics analysis further promoted our hypothesis, showing beneficial effects of circZFPM2 on cardiac contractility and mitochondrial function. Collectively, our data highlight that circZFPM2 serves as a promising target for the treatment of cardiac hypertrophy including HCM.

Telomerase is essential for cardiac differentiation and sustained metabolism of human cardiomyocytes.

Telomeres as the protective ends of linear chromosomes, are synthesized by the enzyme telomerase (TERT). Critically short telomeres essentially contribute to aging-related diseases and are associated with a broad spectrum of disorders known as telomeropathies. In cardiomyocytes, telomere length is strongly correlated with cardiomyopathies but it remains ambiguous whether short telomeres are the cause or the result of the disease. In this study, we employed an inducible CRISPRi human induced pluripotent stem cell (hiPSC) line to silence TERT expression enabling the generation of hiPSCs and hiPSC-derived cardiomyocytes with long and short telomeres. Reduced telomerase activity and shorter telomere lengths of hiPSCs induced global transcriptomic changes associated with cardiac developmental pathways. Consequently, the differentiation potential towards cardiomyocytes was strongly impaired and single cell RNA sequencing revealed a shift towards a more smooth muscle cell like identity in the cells with the shortest telomeres. Poor cardiomyocyte function and increased sensitivity to stress directly correlated with the extent of telomere shortening. Collectively our data demonstrates a TERT dependent cardiomyogenic differentiation defect, highlighting the CRISPRi TERT hiPSCs model as a powerful platform to study the mechanisms and consequences of short telomeres in the heart and also in the context of telomeropathies.

Generation of human induced pluripotent stem cell line MHHi029-A from a male Fabry disease patient carrying c.959A > T mutation.

Fabry disease (FD) is a rare and inherited monogenetic disease caused by mutations in the X-chromosomal alpha-galactosidase A gene GLA concomitant with accumulation of its substrate globotriaosylceramide (Gb3) and multi-organ symptoms. We derived an induced pluripotent stem cell line, MHHi029-A, from a male FD patient carrying a c.959A > T missense mutation in the GLA gene. The hiPSCs show a normal karyotype, expression of pluripotency markers and trilineage differentiation capacity. Importantly, they present the patient-specific mutation in the GLA gene and are therefore a valuable resource for investigating the FD mechanism and identifying novel therapies.

Circulating miR-let7a levels predict future diagnosis of chronic thromboembolic pulmonary hypertension.

Distinct patterns of circulating microRNAs (miRNAs) were found to be involved in misguided thrombus resolution. Thus, we aimed to investigate dysregulated miRNA signatures during the acute phase of pulmonary embolism (PE) and test their diagnostic and predictive value for future diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). Microarray screening and subsequent validation in a large patient cohort (n = 177) identified three dysregulated miRNAs as potential biomarkers: circulating miR-29a and miR-720 were significantly upregulated and miR-let7a was significantly downregulated in plasma of patients with PE. In a second validation study equal expression patterns for miR-29a and miR-let7a regarding an acute event of recurrent venous thromboembolism (VTE) or deaths were found. MiR-let7a concentrations significantly correlated with echocardiographic and laboratory parameters indicating right ventricular (RV) dysfunction. Additionally, circulating miR-let7a levels were associated with diagnosis of CTEPH during follow-up. Regarding CTEPH diagnosis, ROC analysis illustrated an AUC of 0.767 (95% CI 0.54-0.99) for miR-let7a. Using logistic regression analysis, a calculated patient-cohort optimized miR-let7a cut-off value derived from ROC analysis of ≥ 11.92 was associated with a 12.8-fold increased risk for CTEPH. Therefore, miR-let7a might serve as a novel biomarker to identify patients with haemodynamic impairment and as a novel predictor for patients at risk for CTEPH.

The role of fibrosis in cardiomyopathies: An opportunity to develop novel biomarkers of disease activity.

Cardiomyopathies encompass a spectrum of heart disorders with diverse causes and presentations. Fibrosis stands out as a shared hallmark among various cardiomyopathies, reflecting a common thread in their pathogenesis. This prevalent fibrotic response is intricately linked to the consequences of dysregulated extracellular matrix (ECM) remodeling, emphasizing its significance in the development and progression the disease. This review explores the ECM involvement in various cardiomyopathies and its impact on myocardial stiffness and fibrosis. Additionally, we discuss the potential of ECM fragments as early diagnosis, prognosis, and risk stratification. Biomarkers deriving from turnover of collagens and other ECM proteins hold promise in clinical applications. We outline current clinical management, future directions, and the potential for personalized ECM-targeted therapies with specific focus on microRNAs. In summary, this review examines the role of the fibrosis in cardiomyopathies, highlighting the potential of ECM-derived biomarkers in improving disease management with implications for precision medicine.

Encapsulating In Vitro Transcribed circRNA into Lipid Nanoparticles Via Microfluidic Mixing.

This chapter serves as a guide for researchers embarking on circular RNA-based translational studies. It provides a foundation for the successful encapsulation of circular RNA into lipid nanoparticles (LNPs) and facilitates progress in this emerging field. Crucial scientific methods and techniques involved in the formulation process, particle characterization, and downstream processing of circ-LNPs are covered. The production of in vitro transcribed circular RNA-containing LNPs based on a commercially available lipid mix is provided, in addition to the fundamentals for successful encapsulation based on lipid mixes composed of single components. Furthermore, the transfection and validation protocols for the identification of a functional and potentially therapeutic circRNA candidate for initial in vitro verification, before subsequent LNP studies, are explained.

A pilot study for risk stratification of ventricular tachyarrhythmia in hypertrophic cardiomyopathy with routine echocardiography parameters.

Ventricular tachyarrhythmia (VTA) are frequent arrhythmias in patients with hypertrophic cardiomyopathy (HCM). Representing a major risk factor for sudden cardiac death, Holter ECG at first clinical presentation appears insufficient. This study aims to investigate the ability of routinely obtained parameters associated with myocardial remodeling in stratifying for VTA in HCM. In this monocentric analysis, patients with HCM underwent 12-channel electrocardiography and echocardiography, including tissue doppler imaging. The study's primary endpoint was the documentation of non-sustained and sustained ventricular tachycardia-summarized as ventricular tachyarrhythmias (VTA) on Holter ECG or active devices. The occurrence of VTA was exploratory. Based on our collective, we developed a risk model regarding VTA. Of 140 HCM patients, 38 (27.1%) had an episode of VTA. Patients with VTA were likelier to have a history of atrial fibrillation (p < 0.001), a thicker interventricular septum (p < 0.001) and lower peak systolic mitral annular velocity (p < 0.001). The parameters were independently associated with endpoint in univariate and multivariate logistic regression. We created a logistic equation and calculated a cut-off value. The resulting ROC curve revealed a discriminative ability with AUC of 0.80 (sensitivity, 63%; specificity, 88%). Our risk model including these widely available parameters is able to distinguish low and high-risk of VTA in patients with HCM.

LIPCAR levels in plasma-derived extracellular vesicles is associated with left ventricle remodeling post-myocardial infarction.

BACKGROUND: Long Intergenic noncoding RNA predicting CARdiac remodeling (LIPCAR) is a long noncoding RNA identified in plasma of patients after myocardial infarction (MI) to be associated with left ventricle remodeling (LVR). LIPCAR was also shown to be a predictor of early death in heart failure (HF) patients. However, no information regarding the expression of LIPCAR and its function in heart as well as the mechanisms involved in its transport to the circulation is known. The aims of this study are (1) to characterize the transporter of LIPCAR from heart to circulation; (2) to determine whether LIPCAR levels in plasma isolated-extracellular vesicles (EVs) reflect the alteration of its expression in total plasma and could be used as biomarkers of LVR post-MI. METHODS: Since expression of LIPCAR is restricted to human species and the limitation of availability of cardiac biopsy samples, serum-free conditioned culture media from HeLa cells were first used to characterize the extracellular transporter of LIPCAR before validation in EVs isolated from human cardiac biopsies (non-failing and ischemic HF patients) and plasma samples (patients who develop or not LVR post-MI). Differential centrifugation at 20,000g and 100,000g were performed to isolate the large (lEVs) and small EVs (sEVs), respectively. Western blot and nanoparticle tracking (NTA) analysis were used to characterize the isolated EVs. qRT-PCR analysis was used to quantify LIPCAR in all samples. RESULTS: We showed that LIPCAR is present in both lEVs and sEVs isolated from all samples. The levels of LIPCAR are higher in lEVs compared to sEVs isolated from HeLa conditioned culture media and cardiac biopsies. No difference of LIPCAR expression was observed in tissue or EVs isolated from cardiac biopsies obtained from ischemic HF patients compared to non-failing patients. Interestingly, LIPCAR levels were increased in lEVs and sEVs isolated from MI patients who develop LVR compared to patients who did not develop LVR. CONCLUSION: Our data showed that large EVs are the main extracellular vesicle transporter of LIPCAR from heart into the circulation independently of the status, non-failing or HF, in patients. The levels of LIPCAR in EVs isolated from plasma could be used as biomarkers of LVR in post-MI patients.

Efficacy and safety of CDR132L in patients with reduced left ventricular ejection fraction after myocardial infarction: Rationale and design of the HF-REVERT trial.

AIM: Inhibition of microRNA (miR)-132 effectively prevents and reverses adverse cardiac remodelling, making it an attractive heart failure (HF) target. CDR132L, a synthetic antisense oligonucleotide selectively blocking pathologically elevated miR-132, demonstrated beneficial effects on left ventricular (LV) structure and function in relevant preclinical models, and was safe and well tolerated in a Phase 1b study in stable chronic HF patients. Patients with acute myocardial infarction (MI) and subsequent LV dysfunction and remodelling have limited therapeutic options, and may profit from early CDR132L treatment. METHODS: The HF-REVERT (Phase 2, multicenter, randomized, parallel, 3-arm, placebo-controlled Study to Assess Efficacy and Safety of CDR132L in Patients with Reduced Left Ventricular Ejection Fraction after Myocardial Infarction) evaluates the efficacy and safety of CDR132L in HF patients post-acute MI (n = 280), comparing the effect of 5 and 10 mg/kg CDR132L, administered as three single intravenous doses 28 days apart, in addition to standard of care. Key inclusion criteria are the diagnosis of acute MI, the development of systolic dysfunction (LV ejection fraction ≤45%) and elevated N-terminal pro-B-type natriuretic peptide. The study consists of a 6-month double-blinded treatment period with the primary endpoint LV end-systolic volume index and relevant secondary endpoints, followed by a 6-month open-label observation period. CONCLUSION: The HF-REVERT trial may underpin the concept of miR-132 inhibition to prevent or reverse cardiac remodelling in post-MI HF. The results will inform the design of subsequent outcome trials to test CDR132L in HF.

Dextrans, Pullulan and Lentinan, New Scaffold Materials for Use as Hydrogels in Tissue Engineering.

The development of hydrogels based on dextrans, pullulan and lentinan to be used in biomedical applications including tissue engineering is reported. Despite the fact that selected polysaccharides such as hyaluronic acid are well established, little is known, how these polysaccharides can be chemically modified to create hydrogels under controlled conditions. In this study we present a small library of chemically modified polysaccharides which are used for a divergent approach to achieve biomedical relevant hydrogels. In this case the crosslinking is based on thio ether formation between thiol modified donor and vinylsulfone or maleimide modified acceptor components. Successful synthesis of the linker systems and coupling at the polysaccharides, hydrogel formation takes place under physiological conditions. We extended the study by coupling small molecules like adhesion factors for increasing cell compatibility as well as a dye for further studies. The different hydrogels were studied to their rheological properties, water uptake, their permeability, biodegrability and their cytotoxicity.

Integration of implantable device therapy in patients with heart failure. A clinical consensus statement from the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC).

Implantable devices form an integral part of the management of patients with heart failure (HF) and provide adjunctive therapies in addition to cornerstone drug treatment. Although the number of these devices is growing, only few are supported by robust evidence. Current devices aim to improve haemodynamics, improve reverse remodelling, or provide electrical therapy. A number of these devices have guideline recommendations and some have been shown to improve outcomes such as cardiac resynchronization therapy, implantable cardioverter-defibrillators and long-term mechanical support. For others, more evidence is still needed before large-scale implementation can be strongly advised. Of note, devices and drugs can work synergistically in HF as improved disease control with devices can allow for further optimization of drug therapy. Therefore, some devices might already be considered early in the disease trajectory of HF patients, while others might only be reserved for advanced HF. As such, device therapy should be integrated into HF care programmes. Unfortunately, implementation of devices, including those with the greatest evidence, in clinical care pathways is still suboptimal. This clinical consensus document of the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC) describes the physiological rationale behind device-provided therapy and also device-guided management, offers an overview of current implantable device options recommended by the guidelines and proposes a new integrated model of device therapy as a part of HF care.

Macrophage-based therapeutic approaches for cardiovascular diseases.

Despite the advances in treatment options, cardiovascular disease (CVDs) remains the leading cause of death over the world. Chronic inflammatory response and irreversible fibrosis are the main underlying pathophysiological causes of progression of CVDs. In recent decades, cardiac macrophages have been recognized as main regulatory players in the development of these complex pathophysiological conditions. Numerous approaches aimed at macrophages have been devised, leading to novel prospects for therapeutic interventions. Our review covers the advancements in macrophage-centric treatment plans for various pathologic conditions and examines the potential consequences and obstacles of employing macrophage-targeted techniques in cardiac diseases.