Diagnostic Value of 99mTc-MIBI Myocardial Perfusion Imaging in Detecting Myocardial Ischemia of Children with Kawasaki Disease and Coronary Artery Lesions.

Pediatric patients with coronary artery lesions (CALs) after Kawasaki disease (KD) may be complicated with myocardial ischemia. Although previous studies in adults have proven the diagnostic value of 99mTc-MIBI myocardial perfusion imaging (MPI) for ischemic heart disease, its feasibility and accuracy in this pediatric population remain uncertain. In this retrospective study, we collected data of 177 pediatric patients (Age range: 6 months to 14 years) who had undergone MPI and coronary artery angiography (CAG) between July 2019 and February 2023. Using the positive result of CAG as the reference standard of myocardial ischemia, we compared the results of 99mTc-MIBI MPI with other non-invasive examinations, including cardiac magnetic resonance imaging (CMRI), echocardiogram, and comprehensive electrocardiogram-related examinations. All patients finished adenosine triphosphate stress MPI without major side effects. The sensitivity of MPI was 79.17%, which was greater than CMRI and echocardiogram (P < 0.05). The negative predictive value and the accuracy of MPI were 89.9% and 71.75%, indicating the advantages over others. Composite monitoring strategy of MPI and CMRI effectively improved the diagnostic performance (P < 0.001). In 4 cases diagnosed with myocardial ischemia by "MPI + CMRI," despite the absence of significant stenosis, multiple giant coronary artery aneurysms (GCAA) were all observed in CAG. 99mTc-MIBI MPI is the preferred non-invasive examination for detecting myocardial ischemia in pediatric patients with CAL after KD. When combined with CMRI, it can enhance diagnostic accuracy. Multiple GCAAs without stenosis may be an isolated risk factor of myocardial ischemia.

Functional assessment of heart-specific enhancers by integrating ChIP-seq data.

BACKGROUND: Identification and functional annotations of regulatory sequences play a pivotal role in heart development and function. METHODS: To generate a map of human heart-specific enhancers, we performed an integrative analysis of 148 chromatin immunoprecipitation coupled to massively parallel sequencing (ChIP-seq) samples with enhancer-associated epigenetic marks from the heart, liver, brain, and kidney. Functional validation of heart-specific enhancer activity was then performed using cultured cells. RESULTS: A 144.6-Mb candidate heart-specific enhancer compendium was generated by integrating the analysis of 148 epigenomic data sets from human and mouse hearts and control tissues. To validate in vivo enhancer activity, we tested 12 of these sequences around 45 CHD-related genes in cultured cells and found that 8 (67%) have reproducible heart-specific enhancer activity. A functional analysis demonstrated that the identified human heart-specific enhancer wf1 regulates the FBN1 gene which is involved in heart disease. CONCLUSIONS: Our study provides an integrative analysis pipeline for ChIP-seq data and identified a comprehensive catalog of human heart-specific enhancers for clinical CHD-related studies. IMPACT: Establishing an efficient way to analyze regulatory regions in CHD is very important. A highly qualified heart-specific enhancer compendium was generated by integrating 148 online ChIP-seq samples. Sixty-seven percent of predicted regulatory sequences have reproducible heart-specific enhancer activity in vivo. Human heart-specific enhancer wf1 regulates the CHD-related FBN1 gene.

The functional verification and analysis of Fugu promoter of cardiac gene tnni1a in zebrafish.

Troponin I type 1b (Tnni1b) is thought to be a novel isoform that is expressed only in the zebrafish heart. Knocking down of tnni1b can lead to cardiac defects in zebrafish. Although both the zebrafish tnni1b and human troponin I1 (TNNI1) genes are thought to be closely associated with fatal cardiac development, the regulatory molecular mechanisms of these genes are poorly understood. Analyzing the functionally conserved sequence, especially in the noncoding regulatory region involved in gene expression, clarified these mechanisms. In this study, we isolated a 3 kb fragment upstream of Fugu tnni1a that can regulate green fluorescence protein (GFP) expression in a heart-specific manner, similar to the pattern of zebrafish homologue expression. Three evolutionarily conserved regions (ECRs) in the 5'-flanking sequence of Fugu tnni1a were identified by sequence alignment. Deletion analysis led to the identification of ECR2 as a core sequence that affects the heart-specific expression function of the Fugu tnni1a promoter. Interestingly, both the Fugu tnni1a promoter and ECR2 sequence were functionally conserved in zebrafish, although they shared no sequence similarity. Together, the findings of our study provided further evidence for the important role of tnni1a homologous in cardiac development and demonstrated that two functionally conserved sequences in the zebrafish and Fugu genomes may be ECRs, despite their lack of similarity.

The tissue-specificity associated region and motif of an emx2 downstream enhancer CNE2.04 in zebrafish.

BACKGROUND: Expression level of EMX2 plays an important role in the development of nervous system and cancers. CNE2.04, a conserved enhancer downstream of emx2, drives fluorescent protein expression in the similar pattern of emx2. METHODS: CNE2.04 truncated or motif-mutated transgenic reporter plasmids were constructed and injected into the zebrafish fertilized egg with Tol2 mRNA at the unicellular stage of zebrafish eggs. The green fluorescence expression patterns were observed at 24, 48, and 72 hpf, and the fluorescence rates of different tissues were counted at 48 hpf. RESULTS: Compared to CNE2.04, CNE2.04-R400 had comparable enhancer activity, while the tissue specificity of CNE2.04-L400 was obviously changed. Motif CCCCTC mutation obviously changed the enhancer activity, while motif CCGCTC mutations also changed it. CONCLUSION: Due to their correlation with tissue specificity, CNE2.04-R400 is associated with the tissue-specificity of CNE2.04, and motif CCCCTC plays an important role in the enhancer activity of CNE2.04.

Comparative sequence analysis and functional validation identified a retina-specific enhancer around zic5 and zic2a.

The spatiotemporal development of vertebrate retina is regulated by a variety of genes. The zinc finger transcription factors zic5 and zic2a are located close to each other in the chromosome. They have similar expression patterns, and both play important roles in the development of the retina and nervous system. Here, we used ECR browser and gfp fluorescence report experiment to identify a 290bp enhancer sequence ECR3, which is located at 3 kb upstream of zic5 and 10 kb downstream of zic2a, and it can drive the specific expression of gfp in the retina. pT2KXIGQ-ECR3 was used to construct a transgenic zebrafish line Tg(ECR3-290: gfp) which first exhibits specific green fluorescence in the whole retina area at 24hpf. Then the expression region was gradually limited to ganglion cell layer (GCL) and lasted through adulthood. This expression pattern is highly consistent with the zic5 and zic2a at retina. These results indicate that the 290bp enhancer might be an important element to regulate the expression of zic5 and zic2a genes in ganglion cells, and this transgenic line is an important tool for studying the development of retina.

Upregulation of miRNA-23a-3p rescues high glucose-induced cell apoptosis and proliferation inhibition in cardiomyocytes.

Maternal hyperglycemia potentially inhibits the development of the fetal heart by suppressing cardiomyocyte proliferation and promoting apoptosis. Different studies have indicated that miRNAs are key regulators of cardiomyocyte proliferation, differentiation, and apoptosis and play a protective role in a variety of cardiovascular diseases. However, the biological function of miRNA-23a in hyperglycemia-related cardiomyocyte injury is not fully understood. The present study investigated the effect of miRNA-23a-3p on cell proliferation and apoptosis in a myocardial injury model induced by high glucose. H9c2 cardiomyocytes were exposed to high glucose to establish an in vitro myocardial injury model and then transfected with miRNA-23a-3p mimics. After miRNA-23a-3p transfection, lens-free microscopy was used to dynamically monitor cell numbers and confluence and calculate the cell cycle duration. CCK-8 and EdU incorporation assays were performed to detect cell proliferation. Flow cytometry was used to measured cell apoptosis. Upregulation of miRNA-23a-3p significantly alleviated high glucose-induced cell apoptosis and cell proliferation inhibition (p < 0.01 and p < 0.0001, respectively). The cell cycle of the miRNA-23a-3p mimics group was significantly shorter than that of the negative control group (p < 0.01). The expression of cell cycle-activating and apoptosis inhibition-associated factors Ccna2, Ccne1, and Bcl-2 was downregulated by high glucose and upregulated by miRNA-23a-3p overexpression in high glucose-injured H9c2 cells. miRNA-23a-3p mimics transfection before high glucose treatment had a significantly greater benefit than transfection after high glucose treatment (p < 0.0001), and the rescue effect of miRNA-23a-3p increased as the concentration increased. This study suggests that miRNA-23a-3p exerted a dose- and time-dependent protective effect on high glucose-induced H9c2 cardiomyocyte injury.