A Comprehensive Review of Management Strategies for Bicuspid Aortic Valve (BAV): Exploring Epidemiology, Aetiology, Aortopathy, and Interventions in Light of Recent Guidelines.

OBJECTIVE: bicuspid aortic valve (BAV) stands as the most prevalent congenital heart condition intricately linked to aortic pathologies encompassing aortic regurgitation (AR), aortic stenosis, aortic root dilation, and aortic dissection. The aetiology of BAV is notably intricate, involving a spectrum of genes and polymorphisms. Moreover, BAV lays the groundwork for an array of structural heart and aortic disorders, presenting varying degrees of severity. Establishing a tailored clinical approach amid this diverse range of BAV-related conditions is of utmost significance. In this comprehensive review, we delve into the epidemiology, aetiology, associated ailments, and clinical management of BAV, encompassing imaging to aortic surgery. Our exploration is guided by the perspectives of the aortic team, spanning six distinct guidelines. METHODS: We conducted an exhaustive search across databases like PubMed, Ovid, Scopus, and Embase to extract relevant studies. Our review incorporates 84 references and integrates insights from six different guidelines to create a comprehensive clinical management section. RESULTS: BAV presents complexities in its aetiology, with specific polymorphisms and gene disorders observed in groups with elevated BAV prevalence, contributing to increased susceptibility to other cardiovascular conditions. The altered hemodynamics inherent to BAV instigate adverse remodelling of the aorta and heart, thus fostering the development of epigenetically linked aortic and heart diseases. Employing TTE screening for first-degree relatives of BAV patients might be beneficial for disease tracking and enhancing clinical outcomes. While SAVR is the primary recommendation for indicated AVR in BAV, TAVR might be an option for certain patients endorsed by adept aortic teams. In addition, proficient teams can perform aortic valve repair for AR cases. Aortic surgery necessitates personalized evaluation, accounting for genetic makeup and risk factors. While the standard aortic replacement threshold stands at 55 mm, it may be tailored to 50 mm or even 45 mm based on patient-specific considerations. CONCLUSION: This review reiterates the significance of considering the multifactorial nature of BAV as well as the need for further research to be carried out in the field.

Restriction of SARS-CoV-2 replication by receptor transporter protein 4 (RTP4).

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is subject to restriction by several interferon-inducible host proteins. To identify novel factors that limit replication of the virus, we tested a panel of genes that we found were induced by interferon treatment of primary human monocytes by RNA sequencing. Further analysis showed that one of the several candidates genes tested, receptor transporter protein 4 (RTP4), that had previously been shown to restrict flavivirus replication, prevented the replication of the human coronavirus HCoV-OC43. Human RTP4 blocked the replication of SARS-CoV-2 in susceptible ACE2.CHME3 cells and was active against SARS-CoV-2 Omicron variants. The protein prevented the synthesis of viral RNA, resulting in the absence of detectable viral protein synthesis. RTP4 bound the viral genomic RNA and the binding was dependent on the conserved zinc fingers in the amino-terminal domain. Expression of the protein was strongly induced in SARS-CoV-2-infected mice although the mouse homolog was inactive against the virus, suggesting that the protein is active against another virus that remains to be identified. IMPORTANCE The rapid spread of a pathogen of human coronavirus (HCoV) family member, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), around the world has led to a coronavirus disease 2019 (COVID-19) pandemic. The COVID-19 pandemic spread highlights the need for rapid identification of new broad-spectrum anti-coronavirus drugs and screening of antiviral host factors capable of inhibiting coronavirus infection. In the present work, we identify and characterize receptor transporter protein 4 (RTP4) as a host restriction factor that restricts coronavirus infection. We examined the antiviral role of hRTP4 toward the coronavirus family members including HCoV-OC43, SARS-CoV-2, Omicron BA.1, and BA.2. Molecular and biochemical analysis showed that hRTP4 binds to the viral RNA and targets the replication phase of viral infection and is associated with reduction of nucleocapsid protein. Significant higher levels of ISGs were observed in SARS-CoV-2 mouse model, suggesting the role of RTP4 in innate immune regulation in coronavirus infection. The identification of RTP4 reveals a potential target for therapy against coronavirus infection.

The NSP14/NSP10 RNA repair complex as a Pan-coronavirus therapeutic target.

The risk of zoonotic coronavirus spillover into the human population, as highlighted by the SARS-CoV-2 pandemic, demands the development of pan-coronavirus antivirals. The efficacy of existing antiviral ribonucleoside/ribonucleotide analogs, such as remdesivir, is decreased by the viral proofreading exonuclease NSP14-NSP10 complex. Here, using a novel assay and in silico modeling and screening, we identified NSP14-NSP10 inhibitors that increase remdesivir's potency. A model compound, sofalcone, both inhibits the exonuclease activity of SARS-CoV-2, SARS-CoV, and MERS-CoV in vitro, and synergistically enhances the antiviral effect of remdesivir, suppressing the replication of SARS-CoV-2 and the related human coronavirus OC43. The validation of top hits from our primary screenings using cellular systems provides proof-of-concept for the NSP14 complex as a therapeutic target.

Obesity and Heart Failure with Preserved Ejection Fraction.

Obese heart failure with preserved ejection fraction (HFpEF) is a distinct HFpEF phenotype. Sodium retention, high circulating neurohormone levels, alterations in energy substrate metabolism, group 3 pulmonary hypertension, pericardial restraint, and systemic inflammation are central pathophysiologic mechanisms. Confirming the diagnosis may be challenging and high suspicion is required. Reduction of visceral adipose tissue, via caloric restriction and/or bariatric surgery, may improve outcomes in obese HFpEF patients. Furthermore, mineralocorticoid receptor inhibition, neprilysin inhibition, and sodium-glucose cotransporter 2 inhibition can ameliorate the effects of adiposity on the cardiovascular system, allowing for promising new treatment targets for the obese HFpEF phenotype.

Polymicrobial Pseudomonas Plus Candida Parapsilosis Endocarditis in an Injection Drug User: Considerations for Diagnosis and Management.

Fungal endocarditis (FE) is a potentially lethal condition and its diagnosis can be challenging due to the low yield from blood cultures. FE should be suspected in patients with associated risk factors despite the identification of positive bacterial blood cultures. The common risk factors for FE discussed in the literature are total parenteral nutrition, immune suppression, prior antimicrobial therapy, intravenous drug addiction, and cardiac surgery. In this report, we discuss a patient who had positive blood cultures for Pseudomonas but was found to have Candida parapsilosis on valve culture. Physicians need to maintain a high index of suspicion for co-infective endocarditis in this patient population.

An ACE2 Microbody Containing a Single Immunoglobulin Fc Domain Is a Potent Inhibitor of SARS-CoV-2.

Soluble forms of angiotensin-converting enzyme 2 (ACE2) have recently been shown to inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We report on an improved soluble ACE2, termed a "microbody," in which the ACE2 ectodomain is fused to Fc domain 3 of the immunoglobulin (Ig) heavy chain. The protein is smaller than previously described ACE2-Ig Fc fusion proteins and contains an H345A mutation in the ACE2 catalytic active site that inactivates the enzyme without reducing its affinity for the SARS-CoV-2 spike. The disulfide-bonded ACE2 microbody protein inhibits entry of SARS-CoV-2 spike protein pseudotyped virus and replication of live SARS-CoV-2 in vitro and in a mouse model. Its potency is 10-fold higher than soluble ACE2, and it can act after virus bound to the cell. The microbody inhibits the entry of ß coronaviruses and virus with the variant D614G spike. The ACE2 microbody may be a valuable therapeutic for coronavirus disease 2019 (COVID-19) that is active against viral variants and future coronaviruses.

Glycan-dependent chikungunya viral infection divulged by antiviral activity of NAG specific chi-like lectin.

Highly pathogenic alphaviruses display complex glycans on their surface. These glycans play a crucial role in viral pathogenesis by facilitating glycan-host interaction during viral entry which can be targeted. Various studies have reported antiviral activity of lectins that bind to the glycans present on the surface of enveloped viruses. This study evaluates the antiviral potential of a chitinase (chi)-like lectin from Tamarind (TCLL) having specificity for N-acetylglucosamine (NAG). Thus, TCLL might bind to N-glycan rich surface of alphavirus and inhibit the entry of virus into the host cells. The direct treatment of TCLL with virus reduced the virus infection. Remarkably, the addition of NAG to TCLL abolished antiviral activity confirming that NAG binding property of TCLL is accountable for its antiviral activity. Further, an ELISA assay confirmed the binding of TCLL to alphaviruses. Taken together, this study will prove to be beneficial in developing lectin therapeutics targeting alphavirus glycan.

Development of an ELISA assay for screening inhibitors against divalent metal ion dependent alphavirus capping enzyme.

Alphavirus non-structural protein, nsP1 has a distinct molecular mechanism of capping the viral RNAs than the conventional capping mechanism of host. Thus, alphavirus capping enzyme nsP1 is a potential drug target. nsP1 catalyzes the methylation of guanosine triphosphate (GTP) by transferring the methyl group from S-adenosylmethionine (SAM) to a GTP molecule at its N7 position with the help of nsP1 methyltransferase (MTase) followed by guanylylation (GT) reaction which involves the formation of m7GMP-nsP1 covalent complex by nsP1 guanylyltransferase (GTase). In subsequent reactions, m7GMP moiety is added to the 5' end of the viral ppRNA by nsP1 GTase resulting in the formation of cap0 structure. In the present study, chikungunya virus (CHIKV) nsP1 MTase and GT reactions were confirmed by an indirect non-radioactive colorimetric assay and western blot assay using an antibody specific for the m7G cap, respectively. The purified recombinant CHIKV nsP1 has been used for the development of a rapid and sensitive non-radioactive enzyme linked immunosorbent assay (ELISA) to identify the inhibitors of CHIKV nsP1. The MTase reaction is followed by GT reaction and resulted in m7GMP-nsP1 covalent complex formation. The developed ELISA nsP1 assay measures this m7GMP-nsP1 complex by utilizing anti-m7G cap monoclonal antibody. The mutation of a conserved residue Asp63 to Ala revealed its role in nsP1 enzyme reaction. Inductively coupled plasma mass spectroscopy (ICP-MS) was used to determine the presence of magnesium ions (Mg2+) in the purified nsP1 protein. The divalent metal ion selectivity and investigation show preference for Mg2+ ion by CHIKV nsP1. Additionally, using the developed ELISA nsP1 assay, the inhibitory effects of sinefungin, aurintricarboxylic acid (ATA) and ribavirin were determined and the IC50 values were estimated to be 2.69 µM, 5.72 µM and 1.18 mM, respectively.

Chikungunya virus inhibition by peptidomimetic inhibitors targeting virus-specific cysteine protease.

Chikungunya virus (CHIKV), a mosquito-borne pathogenic virus that reemerged and caused epidemic in the Indian Ocean island of La Réunion, is a potential public health threat. Currently there is no antiviral drug or vaccine commercially available for the treatment of chikungunya fever, which necessitates the urge for an effective antiviral therapy for chikungunya treatment. In the present study, a FRET based protease assay was used to analyze the proteolytic activity of chikungunya nsP2 protease (CHIKV nsP2pro) - an essential viral enzyme, with fluorogenic substrate peptide. This protease assay was used to assess the inhibitory activity of Pep-I (MMsINC® database ID MMs03131094) and Pep-II (MMsINC® database ID MMs03927237), peptidomimetic compounds identified in a previous study by our group. Both compounds inhibited CHIKV nsP2pro with half maximal inhibition concentration (IC50) values of ∼34 µM and ∼42 µM, respectively. Kinetic studies showed that the inhibition constant (Ki) value is 33.34 ±â€¯2.53 µM for Pep-I and 45.89 ±â€¯4.38 µM for Pep-II. Additionally, these two compounds significantly inhibited CHIKV replication in BHK-21 cells at concentrations much lower than their cytotoxic concentrations. Intriguingly, these compounds did not show inhibitory effect on Sindbis virus. This suggests that Pep-I and Pep-II compounds identified as CHIKV nsP2 substrate peptidomimetics, specifically inhibit CHIKV replication.

Evaluation of antiviral activity of piperazine against Chikungunya virus targeting hydrophobic pocket of alphavirus capsid protein.

Small heterocyclic molecules such as piperazine are potential pharmacotherapeutic agents and binding of these molecules to the hydrophobic pocket of capsid protein (CP) offers a new perspective for therapeutic intervention. Here, we report the crystal structure of CP from Aura virus (AVCP) in complex with piperazine at 2.2 Å resolution. Piperazine binds to the conserved hydrophobic pocket of CP where dioxane based antivirals bind. Comparative structural studies of the piperazine-bound AVCP structure with the apo, active and dioxane-bound AVCP structures provide insights into the conformational variations in the pocket. Additionally, the molecular docking studies showed that piperazine binds into the hydrophobic pocket of Chikungunya virus CP (CVCP) with more affinity than with AVCP. Furthermore, the antiviral activity of piperazine against Chikungunya virus (CHIKV) was investigated by plaque reduction and immunofluorescence assays. The AVCP-piperazine complex may serve as a lead scaffold for structure-based design of piperazine derivatives as alphaviral inhibitors. The antiviral properties of piperazine provide its usefulness for further investigations towards the development of piperazine based anti-alphaviral drugs.

Ultrasound Assisted Catheter Directed Thrombolysis in the Management of a Right Atrial Thrombus: A New Weapon in the Armamentarium?

Catheter related thrombosis (CRT) is a commonly encountered entity fraught with substantial risk for mortality secondary to various complications including pulmonary embolism (PE), tricuspid regurgitation, endocarditis, right sided heart failure, and cardiogenic and septic shock. CRT carries a mortality rate of 18% in hemodialysis patients and more than 40% in nonhemodialysis patients. Management strategies include systemic anticoagulation, systemic thrombolysis, surgical evacuation, and percutaneous retrieval with no established guidelines. Ultrasound assisted catheter directed thrombolysis emerges as promising modality with a relatively lower risk of hemorrhage compared to systemic thrombolysis. We report a case of a 75-year-old man with dialysis catheter related thrombosis without PE for which ultrasound assisted catheter directed thrombolysis was used successfully as an alternative therapy.

Actinomycotic endocarditis of the eustachian valve: a rare case and a review of the literature.

Eustachian valve endocarditis caused by Actinomyces species is extremely rare. A literature review revealed only one reported case-caused by Actinomyces israelii in an intravenous drug abuser. Our patient, a 30-year-old woman who at first appeared to be in good health, presented with fever, a large mobile mass on the eustachian valve, and extensive intra-abdominal and pelvic masses that looked malignant. Histopathologic examination of tissue found in association with an intrauterine contraceptive device revealed filamentous, branching microorganisms consistent with Actinomyces turicensis. This patient was treated successfully with antibiotic agents. In addition to presenting a new case of a rare condition, we discuss cardiac actinomycotic infections in general and eustachian valve endocarditis in particular: its predisposing factors, clinical course, sequelae, and our approaches to its management.

Caspase-3 short hairpin RNAs: a potential therapeutic agent in neurodegeneration of aluminum-exposed animal model.

There is abundant evidence supporting the role of caspases in the development of neurodegenerative disease, including Alzheimer's disease (AD). Therefore, regulating the activity of caspases has been considered as a therapeutic target. However, all the efforts on AD therapy using pan-caspase inhibitors have failed because of uncontrolled adverse effects. Alternatively, the specific knockdown of caspase-3 gene through RNA interference (RNAi) could serve as a future potential therapeutic strategy. The aim of the present study is to down-regulate the expression of caspase-3 gene using lentiviral vector-mediated caspase-3 short hairpin RNA (LV-Caspase-3 shRNA). The effect of LV-Caspase-3 shRNA on apoptosis induced by aluminum (Al) was investigated in primary cultured cortical neurons and validated in C57BL/6J mice. The results indicated an increase in apoptosis and caspase-3 expression in primary cultured neurons and the cortex ofmice exposed to Al, which could be down-regulated by LV-Caspase-3 shRNA. Furthermore, LV-Caspase-3 shRNA reduced neural cell death and improved learning and memory in C57BL/6J mice treated with Al. Our results suggest that LV-caspase-3 shRNA is a potential therapeutic agent to prevent neurodegeneration and cognitive dysfunction in aluminum- exposed animal models. The findings provide a rational gene therapy strategy for AD.

Noise versus signal: the clinical implications of an increasingly sensitive troponin assay for patients with suspected acute coronary syndrome.

OBJECTIVES: To evaluate the clinical impact of a troponin assay switch in suspected acute coronary syndromes (ACS). METHODS: Retrospective analysis of ACS cases in the 3 months before and after changing to a contemporary, higher sensitivity troponin assay. Admitting diagnosis, proportion with a positive result, initial treatment and testing, coronary artery intervention, inhospital events, and final discharge diagnosis were compared by assay group. RESULTS: Seven hundred seventy patients were included: 319 (41.4%) preassay and 451 (58.6%) postassay. Preassay change, non-ST segment elevation myocardial infarction at admission (43.0% vs. 70.5%; diff [95% confidence interval (CI)] = -27.5 [-34.2, -20.6]) was diagnosed less often, and a positive troponin was less common (33.2% vs. 72.3%; diff [95% CI] = -39.1 [-45.4, -32.2]). However, anticoagulation (53.3% vs. 42.4%; diff [95% CI] = 10.9 [3.8, 18.0]) and cardiac catheterization use were more frequent (53.9% vs. 41.9%; diff [95% CI] = 12.0 [19.0, 48.5]). There was no difference in coronary intervention (41.9% vs. 40.7%; diff [95% CI] = 1.2 [-9.0, 11.2]) by assay period. Inhospital event were rare (unstable ventricular arrhythmia = 1.2%, cardiac arrest = 3.4%, death = 4.4%) with no difference between groups. A non-ACS diagnosis at discharge was more common in the postassay group (31.6% vs. 46.5%; diff [95% CI] = 14.9 [7.9, 21.6]). CONCLUSIONS: Although non-ST segment elevation myocardial infarction diagnosis at admission and a positive troponin were more frequent postassay change, rates of anticoagulation and cardiac catheterization were lower and a non-ACS diagnosis at discharge was more common. These data suggest an evolving understanding and clinical impact of contemporary troponin assays when used in real-world settings.

Two-dimensional strain profiles in patients with physiological and pathological hypertrophy and preserved left ventricular systolic function: a comparative analyses.

OBJECTIVE: This study was designed to examine the utility of two-dimensional strain (2DS) or speckle tracking imaging to typify functional adaptations of the left ventricle in variant forms of left ventricular hypertrophy (LVH). DESIGN: Cross-sectional study. SETTING: Urban tertiary care academic medical centres. PARTICIPANTS: A total of 129 subjects, 56 with hypertrophic cardiomyopathy (HCM), 34 with hypertensive left ventricular hypertrophy (H-LVH), 27 professional athletes with LVH (AT-LVH) and 12 healthy controls in sinus rhythm with preserved left ventricular systolic function. METHODS: Conventional echocardiographic and tissue Doppler examinations were performed in all study subjects. Bi-dimensional acquisitions were analysed to map longitudinal systolic strain (automated function imaging, AFI, GE Healthcare, Waukesha, Wisconsin, USA) from apical views. RESULTS: Subjects with HCM had significantly lower regional and average global peak longitudinal systolic strain (GLS-avg) compared with controls and other forms of LVH. Strain dispersion index, a measure of regional contractile heterogeneity, was higher in HCM compared with the rest of the groups. On receiver operator characteristics analysis, GLS-avg had excellent discriminatory ability to distinguish HCM from H-LVH area under curve (AUC) (0.893, p<0.001) or AT-LVH AUC (0.920, p<0.001). Tissue Doppler and LV morphological parameters were better suited to differentiate the athlete heart from HCM. CONCLUSIONS: 2DS (AFI) allows rapid characterisation of regional and global systolic function and may have the potential to differentiate HCM from variant forms of LVH.

Birth weight, cord blood lipoprotein and apolipoprotein levels in Indian newborns.

OBJECTIVES: Primordial prevention of chronic disease is of clinical and public health importance. Considering the fetal onset of atherosclerosis, we aimed to determine the cord blood level of lipoproteins and apolipoproteins as well as their correlation with birth weight and gestational age. METHODS: This cross-sectional study comprised 100 healthy Indian newborns. Ten ml. of cord blood was collected from placental end of umbilical vein. Serum was separated by centrifugation and analyzed on the same day for lipid profile including total cholesterol (TC), triglycerides (TG), high density lipoprotein- cholesterol (HDL-C), very low density lipoproteincholesterol (VLDL) and low density lipoprotein-cholesterol (LDL-C), apolipoproteins A-I and B (ApoA-I, ApoB). Atherogenic index (AI) was calculated as the ratio of ApoB to ApoA-I. RESULTS: Cord blood of female newborns had higher TC, HDL-C, LDL-C, Apo A-I, Apo B and AI as compared to male newborns, whereas TG and VLDL-C were higher in male than in female newborns. Significant positive correlation was observed between cord blood Apo A-I and HDL-C (r= 0.45, p<0.01), and between cord blood Apo-B and LDL-C (r= 0.44, p<0.01). Non-significant inverse correlation was observed between Apo A-I and ApoB with gestational age. There was a significant inverse correlation between TG and gestational age (r= -0.197, p <0.05). Positive non-significant correlation was observed between AI and birth weight (r=0.046, p>0.05). CONCLUSIONS: These findings are another confirmatory evidence for the association of prenatal factors with cord blood lipid profile, and can serve as starting point for studying lipid transport system changes during early life.