Evaluation of Infective Endocarditis in Children: A 19-Year Retrospective Study in Taiwan.

BACKGROUND: Infective endocarditis (IE) is an important cause of morbidity and mortality in pediatric patients with heart disease. Little literature has explored differences in the presentation of endocarditis in children with and without heart disease. This study aimed to compare the clinical outcomes and determine the risk of in-hospital death in the study population. METHODS: Data were retrospectively collected from 2001 to 2019 from the Chang Gung Research Database (CGRD), which is the largest collection of multi-institutional electronic medical records in Taiwan. Children aged 0-20 years with IE were enrolled. We extracted and analyzed the demographic and clinical features, complications, microbiological information, and outcomes of each patient. RESULTS: Of the 208 patients with IE, 114 had heart disease and 94 did not. Compared to those without heart disease, more streptococcal infections (19.3% vs. 2.1%, p < 0.001) and cardiac complications (29.8% vs. 6.4%, p < 0.001) were observed in patients with heart disease. Although patients with heart disease underwent valve surgery more frequently (43.9% vs. 8.5%, p < 0.001) and had longer hospital stays (28.5 vs. 12.5, p = 0.021), their mortality was lower than that of those without heart disease (3.5% vs. 10.6%, p = 0.041). Thrombocytopenia was independent risk factor for in-hospital mortality in pediatric patients with IE (OR = 6.56, 95% CI: 1.43-40.37). CONCLUSION: Among pediatric patients diagnosed with IE, microbiological and clinical features differed between those with and without heart disease. Platelet counts can be used as a risk factor for in-hospital mortality in pediatric patients with IE.

RNA editing of 5-HT2C R impairs insulin secretion of pancreatic beta cells via altered store-operated calcium entry.

Recent studies emphasize the importance of 5-HT2C receptor (5-HT2C R) signaling in the regulation of energy homeostasis. The 5-HT2C R is the only G-protein-coupled receptor known to undergo post-transcriptional adenosine to inosine (A-to-I) editing by adenosine deaminase acting on RNA (ADAR). 5-HT2C R has emerged as an important role in the modulation of pancreatic ß cell functions. This study investigated mechanisms behind the effects of palmitic acid (PA) on insulin secretion in different overexpressed 5-HT2C R edited isoforms in pancreatic MIN6 ß cells. Results showed that the expressions of 5HT2C R and ADAR2 were upregulated in the pancreatic islets of mice fed with high-fat diet (HFD) compared to control mice. PA treatment significantly induced the expressions of 5-HT2C R and ADAR2 in pancreatic MIN6 ß cells. PA treatment significantly induced the editing of 5-HT2C R in pancreatic MIN6 ß cells. There was no significant difference in cell viability between naïve cells and three overexpressed 5-HT2C R edited isoforms in pancreatic MIN6 ß cells. Overexpressed 5-HT2C R edited isoforms showed reduced glucose-stimulated insulin secretion (GSIS) compared with green fluorescent protein (GFP) expressed cells. Moreover, 5-HT2C R edited isoforms displayed reduced endoplasmic reticulum (ER) calcium release and store-operated calcium entry (SOCE) activation, probably through inhibition of stromal interaction molecule 1 trafficking under PA treatment. Altogether, our results show that PA-mediated editing of 5-HT2C R modulates GSIS through alteration of ER calcium release and SOCE activation in pancreatic MIN6 ß cells.

Characterization of Adult Canine Kidney Epithelial Stem Cells That Give Rise to Dome-Forming Tubular Cells.

Dome formation can occur in cultured tubular epithelial cells originating from various tissues, including the mammary gland and the kidney. The isolation and characterization of normal kidney epithelial stem cells that give rise to dome-forming tubular cells have never been reported. We attempted to isolate and characterize canine kidney epithelial stem cells using a simple cell culture method that we have previously used to isolate other adult human stem cells. Dome-forming kidney epithelial cells were derived from dissociated adult canine kidney tissues that were cultured in a modified keratinocyte serum-free medium supplemented with N-acetyl-l-cysteine, l-ascorbic acid 2-phosphate, nicotinamide, and fetal bovine serum. These cells exhibited high self-renewal capacity in long-term culture (growth for >13 months and 30 cumulative population doublings) and exhibited characteristics of stem cells, including (1) deficiency in gap junctional intercellular communication, (2) anchorage-independent growth, (3) expression of stem cell markers octamer-binding transcription factor 4 and SRY (sex determining region Y)-box 2, (4) expression of cell surface markers CD24 and CD133, and (5) multipotent differentiation into osteoblasts, adipocytes, chondrocytes, and dome-forming tubular cells. Most of these characteristics are shared by the well-known canine renal tubule-derived immortalized Madin-Darby Canine Kidney cell line. Furthermore, the putative canine kidney stem cells developed in this study formed budding tubule-like organoids on Matrigel and required high cell density (>4,000 cells/cm2) for sustained growth and confluency for dome formation. The signal transducer and activator of transcription-3 (STAT3) phosphorylation inhibitor, AG490, inhibited colony-forming efficiency and dome formation, whereas lipopolysaccharide, an activator of STAT3, increased colony-forming efficiency in a dose-dependent manner. These results are consistent with the hypothesis that high cell density induces STAT3 expression, which promotes both stem cell self-renewal and differentiation into tubular cells. Our novel cell culture method should be useful for the future development of normal human kidney stem cells for clinical applications and for studying mechanisms of nephrotoxicity.

Left Ventricle Decompression Strategies in Pediatric Peripheral Extracorporeal Membrane Oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is widely used in patients with potentially reversible acute cardiac and/or pulmonary failure who are unresponsive to conventional treatment. Patients with profound left ventricular (LV) dysfunction under venous-arterial (V-A) ECMO may experience LV distention, pulmonary edema, and thrombus formation. It is critical to unload the left ventricle to prevent such complications. The aim of this study was to identify the risks, timing and methods of LV decompression in pediatric peripheral ECMO. METHODS: Between August 2006 and November 2017, 51 patients received peripheral ECMO support in our pediatric intensive care unit. All of them were less than 18 years of age and non-cardiotomy surgery-related. We retrospectively reviewed the patients' clinical presentations, decompression methods and outcomes. RESULTS: The overall success rate of ECMO removal was 76.5% (39/51), and the survival rate after discharge was 62.7% (32/51). The myocarditis group had the most favorable outcomes among the ECMO patients (100% survival). LV decompression was needed in 12 patients who had profound LV dysfunction under V-A ECMO. Five patients received medical treatment successfully, and the other 7 patients underwent intra-aortic balloon pump (IABP) procedures. In the IABP group, 1 patient still needed further pigtail-decompression. All of our decompression patients survived with good neurological outcomes (Glasgow Outcome Scale 5). CONCLUSIONS: The patients with profound LV dysfunction under peripheral VA ECMO were at risk of thromboembolic events and LV decompress was needed. If medical decompression fails, IABP is a feasible approach for LV decompression in pediatric peripheral ECMO.

Homocysteine and Arginine-to-Asymmetric Dimethylarginine Ratio Associated With Blood Pressure Abnormalities in Children With Early Chronic Kidney Disease.

BACKGROUND: Less attention has been paid to evaluating subclinical cardiovascular disease (CVD) in the early stage of pediatric chronic kidney disease (CKD). Ambulatory blood pressure monitoring (ABPM) and arterial stiffness are the earliest detectable assessments of subclinical CVD. Asymmetric dimethylarginine (ADMA) is an analog of L-arginine (ARG) that inhibits nitric oxide (NO) production; thus the ARG-to-ADMA ratio (AAR) is an index of NO. Homocysteine (HCY) is a risk factor for CVD and it can be metabolized to L-cysteine (CYS). Given that HCY and ADMA/NO are closely linked and related to hypertension, we therefore investigated whether ARG and HCY metabolites, arterial stiffness parameters, ABPM profile, and left ventricular hypertrophy (LVH) are interrelated in children and adolescents with early CKD. METHODS AND RESULTS: This cross-sectional study included 57 pediatric patients with CKD stages 1-3. Two-thirds of the children with CKD stages 1-3 exhibited BP abnormalities accessed by ABPM. Children with CKD stages 2-3 had higher HCY, but lower CYS levels. The plasma HCY level was increased in children with LVH and abnormal ABPM. Systolic BP positively correlated with biomarkers AAR, HCY, and CYS. LV mass positively correlated with AAR, HCY, and CYS. CONCLUSIONS: BP abnormalities were prevalent and associated with AAR, HCY, and CYS in children with early CKD. Our data highlighted the effect of NO and the HCY pathway on CKD-related hypertension.

Differential regulation of human aortic smooth muscle cell proliferation by monocyte-derived macrophages from diabetic patients.

Macrophage accumulation in the arterial wall and smooth muscle cell (SMC) proliferation are features of type 2 diabetes mellitus (DM) and its vascular complications. However, the effects of diabetic monocyte-derived macrophages on vascular SMC proliferation are not clearly understood. In the present study, we investigated the pro-proliferative effect of macrophages isolated from DM patients on vascular SMCs. Macrophage-conditioned media (MCM) were prepared from macrophages isolated from DM patients. DM-MCM treatment induced HASMC proliferation, decreased p21(Cip1) and p27(Kip1) expressions, and increased microRNA (miR)-17-5p and miR-221 expressions. Inhibition of either miR-17-5p or miR-221 inhibited DM-MCM-induced cell proliferation. Inhibition of miR-17-5p abolished DM-MCM-induced p21(Cip1) down-regulation; and inhibition of miR-221 attenuated the DM-MCM-induced p27(Kip1) down-regulation. Furthermore, blocking assays demonstrated that PDGF-CC in DM-MCM is the major mediators of cell proliferation in SMCs. In conclusion, our present data support the hypothesis that SMC proliferation stimulated by macrophages may play critical roles in vascular complications in DM patients and suggest a new mechanism by which arterial disease is accelerated in diabetes.

Augmented TLR2 expression on monocytes in both human Kawasaki disease and a mouse model of coronary arteritis.

BACKGROUND: Kawasaki disease (KD) of unknown immunopathogenesis is an acute febrile systemic vasculitis and the leading cause of acquired heart diseases in childhood. To search for a better strategy for the prevention and treatment of KD, this study compared and validated human KD immunopathogenesis in a mouse model of Lactobacillus casei cell wall extract (LCWE)-induced coronary arteritis. METHODS: Recruited subjects fulfilled the criteria of KD and were admitted for intravenous gamma globulin (IVIG) treatment at the Kaohsiung Chang Gung Memorial Hospital from 2001 to 2009. Blood samples from KD patients were collected before and after IVIG treatment, and cardiovascular abnormalities were examined by transthoracic echocardiography. Wild-type male BALB/c mice (4-week-old) were intraperitoneally injected with LCWE (1 mg/mL) to induce coronary arteritis. The induced immune response in mice was examined on days 1, 3, 7, and 14 post injections, and histopathology studies were performed on days 7 and 14. RESULTS: Both human KD patients and LCWE-treated mice developed coronary arteritis, myocarditis, valvulitis, and pericarditis, as well as elevated plasma levels of interleukin (IL)-2, IL-6, IL-10, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α in acute phase. Most of these proinflammatory cytokines declined to normal levels in mice, whereas normal levels were achieved in patients only after IVIG treatment, with a few exceptions. Toll-like receptor (TLR)-2, but not TLR4 surface enhancement on circulating CD14+ monocytes, was augmented in KD patients before IVIG treatment and in LCWE-treated mice, which declined in patients after IVIG treatment. CONCLUSION: This result suggests that that not only TLR2 augmentation on CD14+ monocytes might be an inflammatory marker for both human KD patients and LCWE-induced CAL mouse model but also this model is feasible for studying therapeutic strategies of coronary arteritis in human KD by modulating TLR2-mediated immune activation on CD14+ monocytes.

Novel method for evaluating tricuspid valve function after tricuspid valve detachment in the repair of perimembranous ventricular septal defects.

Tricuspid valve detachment has been used for decades in the repair of type II ventricular septal defects (VSDs); however, the procedure can damage the tricuspid valve and conduction system. We retrospectively reviewed 177 consecutive type II VSD repairs performed at our hospital from 1997 through 2004. Patients were included if they had symptoms, pulmonary hypertension, or a Qp/Qs ratio>1.5: 86 underwent tricuspid valve detachment (TVD group) and 84 underwent VSD repair without this detachment (non-TVD group). There was no significant difference between groups in age, body weight, VSD size, Qp/Qs ratio, follow-up duration, or incidence of residual shunting. Cross-clamp times (109.6±42.6 vs 92.2±38.1 min) and cardiopulmonary bypass times (155.1±53.8 vs 137±47 min) were longer in the TVD group. No patients developed tricuspid stenosis or heart block. After excluding patients who underwent tricuspid repair, we found similar grades of postoperative tricuspid regurgitation in both groups. In applying our novel criterion (last postoperative regurgitation grade minus preoperative regurgitation grade) to evaluate changes between preoperative and postoperative tricuspid regurgitation, we found significant deterioration in the non-TVD group (P=0.018). Had conventional evaluation methods been used, severity in the groups would not have differed significantly. Our method enables additional evaluation of late tricuspid function in individual patients. Tricuspid valve detachment is safe for type II VSD repair and has no adverse effect on late tricuspid valve function. In addition, we recommend the interrupted-suture technique for leaflet reattachment.

Transpulmonary arterial repair of type 1 ventricular septal defect will induce pulmonary regurgitation: appraisal of subpulmonic approach.

OBJECTIVE: A transpulmonary arterial approach to repair type I ventricular septal defect is the standard. However, the possible adverse effect on the pulmonary valve by this technique has not been investigated. METHODS: A retrospective study reviewing type I ventricular septal defect repair from January 1991 to May 2010 was conducted. Of the 142 cases, the ventricular septal defect was repaired via the transpulmonary arterial route in 77 patients (54.2%, PA group) and via the subpulmonic route in 65 patients (45.8%, SP group). All patients received serial annual transthoracic color Doppler echocardiographic evaluation of pulmonary valve function. RESULTS: The age at operation ranged from 1.2 to 272 months (median, 35.0 months; mean, 50.4 months). The mean follow-up period was 96.2 months (range, 2-234 months). Between the PA and SP groups, there was no significant difference in age, body weight, ventricular septal defect size, left to right shunt amount, mean pulmonary arterial pressure, and preoperative pulmonary stenosis or regurgitation. Postoperatively, there was no significant difference in the ejection fraction or incidence of residual ventricular septal defect, right bundle branch block, and pulmonary stenosis. However, the incidence of postoperative pulmonary regurgitation of more than moderate and the total scale of postoperative pulmonary regurgitation were both significantly higher in the PA group (16.9% vs 4.6% and 1.7 ± 0.1 vs 1.4 ± 0.1, P = .031 and .019, respectively). CONCLUSIONS: Although the transpulmonary arterial approach for type I ventricular septal defect repair has been advocated for decades, considering the adverse effect on pulmonary valve competency, the subpulmonic approach may be an alternative.

Regulation of cyclooxygenase-2 expression in human bladder epithelial cells infected with type I fimbriated uropathogenic E. coli.

The type 1 fimbriae of uropathogenic Escherichia coli (UPEC) have been described as important for the establishment of bladder infections and urinary tract infections (UTI). Urinary prostaglandin (PG) levels and cyclooxygenase (COX)-2 expression in urine particulates may increase with infectious and inflammatory processes, including UTIs. We investigated the mechanisms underlying the modulation of COX-2 expression through the invasion of type 1 fimbriated UPEC strain J96 (J96-1) in human bladder 5637 cells. Bladder 5637 cells infected with J96-1 induced increases in the expression of COX-2 and secretion of PGE(2) . By using specific inhibitors and short hairpin RNA (shRNA), we have demonstrated that the activation of extracellular signal-related kinase (ERK), c-Jun-NH(2) -terminal kinase (JNK) and p38 MAPK pathways is critical for J96-1-induced COX-2 expression. Luciferase reporters and chromatin immunoprecipitation assays suggest that J96-1 invasion increases NF-κB- and AP-1-DNA-binding activities in 5637 cells. Inhibition of NF-κB and AP-1 activations blocked the J96-1-induced COX-2 promoter activity and expression. The effect of J96-1 on 5637 cell signalling and COX-2 expression is mediated by Toll-like receptor (TLR)-4. In summary, our findings provide the molecular pathways underlying type 1 fimbriated J96-dependent COX-2 expression in 5637 cells, providing insight into the function of UPEC invasion in bladder epithelial cells.

High glucose-treated macrophages augment E-selectin expression in endothelial cells.

E-selectin expression by endothelial cells (ECs) is crucial for leukocyte recruitment during the inflammatory response. Macrophage accumulation and serum E-selectin elevation are features of type 2 diabetes mellitus. However, the interactions between macrophages and ECs in regulating vascular endothelial function are not clearly understood. We investigated the mechanisms underlying the modulation of EC E-selectin expression by high glucose (HG)-treated macrophages. Macrophage-conditioned media (MCM) were prepared from HG-treated macrophages. EC stimulation with HG-MCM induced increases the expression and secretion of E-selectin. By using specific inhibitors and small interfering RNAs, we demonstrate that the activation of the JNK and p38 MAPK pathways are critical for HG-MCM-induced E-selectin expression. Transcription factor ELISA and chromatin immunoprecipitation assays further showed that HG-MCM increases the NF-κB- and AP-1 DNA-binding activities in ECs. The inhibition of NF-κB and AP-1 activation by specific siRNAs blocks the HG-MCM-induced E-selectin promoter activity and expression. Protein arrays and blocking assays using neutralizing antibodies demonstrated that macrophage inflammatory protein 1α and 1ß in HG-MCM are major mediators for the induction of EC E-selectin expression. These data support the hypothesis that E-selectin up-regulation stimulated by macrophages may play an active role in atherogenesis in the HG condition and suggest a new mechanism by which arterial disease is accelerated in diabetes.

Recurrent congenital diaphragmatic hernia in Ehlers-Danlos syndrome.

Ehlers-Danlos syndrome (EDS) includes a group of connective tissue disorders with abnormal collagen metabolism and a diverse clinical spectrum. We report two siblings with EDS who both presented with congenital diaphragmatic hernia (CDH). The elder sister suffered from recurrent diaphragmatic hernia twice and EDS was overlooked initially. Echocardiography as well as contrast-enhanced magnetic resonance angiography (MRA) showed dilatation of the pulmonary artery, and marked elongation and tortuosity of the aorta and its branches. A diagnosis of EDS was eventually established when these findings were coupled with the clinical features of hyperelastic skin. Her younger brother also had similar features. This report emphasizes that EDS may present as CDH in a small child which could easily be overlooked. Without appropriate surgery, diaphragmatic hernia might occur. Echocardiographic screening is recommended in patients with CDH. Contrast-enhanced MRA can be helpful in delineation of abnormally tortuous aortic great vessels that are an important clue to the early diagnosis of EDS.

Catheter-malposition-induced cardiac tamponade via contrast media leakage during computed tomography study.

We present a rare case of a central venous catheter-malposition-induced life-threatening cardiac tamponade as a result of computed tomography (CT) with contrast enhancement in an infant with a ventricular septal defect and pulmonary atresia after a modified Blalock-Taussig shunt. The diagnosis was confirmed by chest radiographs and CT study with catheter perforation through the right atrial wall and extravasation of the contrast medium into the pericardium, leading to cardiac tamponade and subsequent circulatory collapse. Two hours after successful cardiopulmonary resuscitation, the patient gradually resumed normal hemodynamic status.

Obstruction of the aorta and left pulmonary artery after Gianturco coil occlusion of patent ductus arteriosus.

We report an unusual case of simultaneous obstruction of the left pulmonary artery and descending thoracic aorta after Gianturco coil occlusion in a 15-month-old boy. The diagnosis was made by echocardiography and cardiac angiography. At surgery, thrombi coating on the protruded parts of the Gianturco coil in the pulmonary artery and aorta were found.

Idiopathic calcific constrictive pericarditis causing pulmonary stenosis associated with a ventricular septal defect mimicking tetralogy of Fallot.

We describe an unusual case of pulmonary stenosis caused by calcific constrictive pericarditis associated with a congenital ventricular septal defect in a 16-year-old boy who had a 2-week history of progressive dyspnea, cyanosis, fatigue, and bilateral leg edema. Echocardiographic findings led to an initial diagnosis of tetralogy of Fallot; however, findings on chest radiography and CT were suggestive of calcific constrictive pericarditis with pulmonary stenosis, which was then confirmed on cardiac catheterization. Total pericardiectomy and repair of the ventricular septal defect resulted in a satisfactory outcome. Follow-up examinations at 6 and 20 months showed that the patient was asymptomatic and considered to have class I New York Heart Association functional status. To our knowledge, this is the first reported case of calcific constrictive pericarditis with pulmonary stenosis associated with a ventricular septal defect.

Aortico-left ventricular tunnel associated with single coronary artery in an infant.

Aortico-left ventricular tunnel (ALVT) is a rare congenital malformation in which an abnormal communication between the aorta and the left ventricle (LV) bypasses the aortic valve. In infants, it usually presents with congestive heart failure. The clinical presentations mimic aortic regurgitation or ruptured sinus of Valsalva aneurysm into the LV. Progressive aortic regurgitation is a common problem in patients with ALVT. ALVT associated with a single coronary artery is extremely rare. We report the case of an infant who had congestive heart failure caused by ALVT. The diagnosis was made by echocardiography and angiography. In addition, a single coronary artery from the noncoronary cusp was found during surgery. Congestive heart failure resolved after successful surgical repair and he was asymptomatic throughout 2 years of follow-up. This case illustrates that early diagnosis of ALVT and corrective surgery can prevent aortic valve incompetence and is associated with a good clinical outcome.