[Diagnosis and treatment of arrhythmogenic cardiomyopathy in children].

Objective: To summarize the clinical manifestations, experiences in diagnosis and treatment of arrhythmogenic cardiomyopathy (ACM) in children. Methods: A retrospective analysis of the clinical manifestations, laboratory tests, radiological features, treatment and follow-up results was conducted in 11 children diagnosed with ACM at the center of congenital heart disease, Beijing anzhen hospital from May 2010 to March 2022. Results: A total of 11 patients aged 2 to 16 years, including 5 males and 6 females were diagnosed with ACM. The clinical manifestations included decreased activity tolerance (7 patients), heart failure (4 patients), syncope or sudden death (3 patients), palpitation (3 patients), and chest tightness and pain (3 patients). Electrocardiogram showed right bundle branch block in 9 cases, paroxysmal ventricular tachycardia in 4 cases, frequent premature ventricular contraction in 4 cases, ventricular pre-excitation in 1 case, left bundle branch block in 1 case, and first degree atrioventricular block in 2 cases. Echocardiography showed enlargement of the right heart, widening of the right ventricular outflow tract, and thinning and bulging of the local wall of the right ventricle with reduced pulsation. Ventricular thrombosis was found in 2 cases. Six children underwent cardiac magnetic resonance imaging, which mainly showed severe enlargement of the right heart, thin free wall of the right ventricle, decreased right heart function, enhanced right ventricular myocardium, and formation of right ventricular aneurysm. Two children underwent myocardial biopsy examination and presented with typical pathological changes of ACM. Genetic tests in five patients revealed DSG2 gene mutation in 2 cases, PKP2 gene mutation in 2 cases, and MYH6 gene mutation in 1 case. All patients received anti heart failure treatment and antiarrhythmic drugs. Two children received anticoagulant treatment due to ventricular thrombosis. Radiofrequency ablation was performed in 2 patients. Glenn procedure was performed in 4 patients, and heart transplantation was performed in 1 patient due to progressive heart failure. The follow-up period ranged from 6 months to 12 years. Two cases died of right heart failure, 6 cases had different degrees of heart failure, 1 case had intermittent chest tightness and pain, and 2 cases were stable. Conclusions: ACM is a progressive genetic cardiomyopathy characterized by decreased activity tolerance, cardiac failure and arrhythmia in pediatric patients. The diagnosis is mainly based on clinical manifestations, electrocardiogram, cardiac imaging changes, and genetic testing. Early detection, diagnosis, and personalized treatment can improve the prognosis.

[Risk factors for syncope in children with severe idiopathic pulmonary arterial hypertension].

Objective: To explore the risk factors for syncope in children with severe idiopathic pulmonary arterial hypertension (IPAH). Methods: Forty-four patients (age<18 years) with IPAH admitted to the Department of Pediatric Cardiology, Beijing Anzhen Hospital between May 2011 and October 2021 were retrospectively included. Patients were devided into syncope group and non-syncope group. Clinical manifestation and hemodynamic parameters including echocardiography, blood tests, right heart catheterization and acute pulmonary vascular expansion test were compared between two groups. Comparisons between groups were performed with unpaired Student t test, or Mann-Whitney U test or chi-square test. Logistic regression was used to calculate the odds ratio (OR) for parameters with statistically significant differences between groups and analyze the statistical correlation. Results: Among the 44 patients, 16 were males, the onset age was (7.2±3.9) years. Twenty-four (55%) children presented with 1 to 11 times of episodes of syncope, and 18 cases of whom induced by physical activity. Syncope group had a larger proportion of New York Heart Association (NYHA) heart function class Ⅲ-Ⅳ (67% (16/24) vs. 25% (5/20), χ2=7.59, P=0.006), higher brain natriuretic peptide (BNP) value ((251±39) vs. (61±40) pg/L, t=-2.18, P=0.035), higher pulmonary-to-aorta diameter ratio (1.6±0.4 vs. 1.4±0.2, t=-2.25, P=0.030) and larger pulmonary vascular resistance index ((22±11) vs. (16±7) WU/m2, t=-2.13, P=0.039) compared with non-syncope group. The proportion of patent foramen ovale (4% (1/24) vs. 45% (9/20), χ2=10.36, P=0.001), left ventricular ejection fraction (LVEF) ((68±5)% vs. (72±8)%, t=2.23, P=0.031) and the positive rate of acute pulmonary vascular expansion test (8% (2/24) vs. 35% (7/20), χ2=4.77, P=0.029) of syncope group were significantly lower than those of non-syncope group. Multiple Logistic regression analysis showed that NYHA heart function Ⅲ-Ⅳ (OR=6.787, 95%CI 1.445-31.880), pulmonary vascular resistance index (OR=1.247, 95%CI 1.020-1.525) and BNP (OR=1.036, 95%CI 1.007-1.066) were independent risk factors for syncope. The patent foramen ovale (OR=0.010, 95%CI 0.000-0.586) was a protective factor for syncope. Conclusions: NYHA cardiac function grade, pulmonary vascular resistance index and BNP are independent risk factors for syncope. Patent foramen ovale is a protective factor for syncope. Exercise is the main inducement of syncope in children with IPAH.

[Insulin-like growth factor-1 alleviates hepatocyte senescence by regulating intranuclear p53-progerin pathway].

To construct cellular senescence model by stimulating primary hepatocytes with hydrogen peroxide (H(2)O(2)). Primary hepatocytes were transfected with p53 siRNA, progerin siRNA or IGF-1 adenovirus vector. The number of SA-ß-Gal stained positive cells and the expression of p53 and progerin were detected. The results showed that p53 siRNA and progerin siRNA had knocked-down the expression of p53 and progerin, and had alleviated the hepatocyte senescence. Transfection of insulin-like growth factor (IGF)-1 adenovirus vector into primary hepatocytes had overexpressed IGF-1, and had alleviated the number of SA-ß-Gal-positive cells. The expression of p53 and progerin was down-regulated in the nucleus, while the expression of p53 was up-regulated in the cytoplasm. The co-precipitation and co-localization of p53 and progerin was decreased in the nuclear region of hepatocytes. IGF-1 overexpression can inhibit intranuclear p53 translocation, alleviate the interaction between p53-progerin, and alleviate hepatocyte senescence.

[Investigation on a cluster epidemic of COVID-19 in a supermarket in Liaocheng, Shandong province].

Objective: To explore clustered epidemic of COVID-19 in Liaocheng city and analyze infection status and chain of transmission of the cases. Methods: A joint investigation team of emergency response for COVID-19 epidemic by CDC professional workers of Liaocheng city and district at two levels on January 30, 2020. According to a indicator case from ZH supermarkets, close contacts and related subjects were tracked and screened on February 1, including ZH supermarket employees, family members having contact history with related cases during January 13-26, supermarket clients during January 16-30 and family members of related cases. an epidemiological investigation was carried on and their swab of nose/throat were collected and were sent to Liaocheng CDC laboratory, real-time fluorescence quantitative RT-PCR was used to detect nucleic acids of SARS-CoV-2. Results: a total of 8 437 people were screened during January 30 to February 9, 2020 (120 employees of supermarket, 93 family members, and 8224 clients of supermarket). The epidemic was caused by ZH cases and brought clustered cases in four families. A total 25 cases of SARS-CoV-2 infection, the total infection rate of subjects was 0.30% (25/8 437) with 22 confirmed cases (0.26%, 22/8 437) and 3 asymptomatic patients (0.04%, 3/8 437), asymptomatic patients accounted for 12.00% (3/25) of all infection cases. The infection rates of supermarket employees, family members of confirmed cases and supermarket clients were 9.17% (11/120), 12.90% (12/93) and 0.02% (2/8 224). Conclusions: This was a cluster epidemic caused by one imported case of COVID-19 in a supermarket of Liaocheng city. Prevention and control of cluster epidemic should be focused on chain of community transmission and family cluster cases. It must also be an attention for transmission risk of asymptomatic patients.

Enhancement of recombinant adeno-associated virus mediated transgene expression by targeted echo-contrast agent.

Ultrasound-targeted microbubble destruction (UTMD) has been recently developed for destroying bubbles carrying drugs or genes, thereby permitting local release of these target molecules. We investigated whether SonoVue®, a new contrast agent that contains phospholipid-stabilized microbubbles filled with sulfur hexafluoride vapor, is effective at delivering a recombinant adeno-associated viral (rAAV) vector to the rat heart by UTMD. Serotype-2 (rAAV2) marked with green fluorescent protein (GFP) as a reporter gene was attached to the surface of sulfur hexafluoride-filled microbubbles. Microbubbles were infused into the tail vein of rats with or without simultaneous echocardiography. Additional controls included ultrasound microbubbles that did not contain virus, virus alone, and virus plus ultrasound. One group underwent echocardiographic destruction of microbubbles followed by rAAV2-GFP infusion. Rats were killed after 4 weeks and examined for GFP expression. Green fluorescence was detected in all groups that received the rAAV2-GFP vector, indicating expression of the rAAV2 transgene; however, GFP expression in the UTMD group was significantly higher than that in control groups. We conclude that ultrasound-mediated destruction mediated by SonoVue is a promising method for delivery of rAAV2 to the heart in vivo.

Self-assembly of novel [3]- and [2]rotaxanes with two different ring components: donor-acceptor and hydrogen bonding interactions and molecular-shuttling behavior.

Three of the first kind of hetero[3]rotaxanes, which comprise one linear component and one neutral and one tetracationic ring component, have been assembled by using the intermolecular hydrogen bonding and donor-acceptor interactions. Three neutral [2]rotaxanes and three tetracationic [2]rotaxanes have also been synthesized as intermediate products or for the sake of property comparison. The linear molecules are incorporated with two glycine subunits, for templating the formation of the neutral tetraamide cyclophane, and one or two hydroquinone subunits, for inducing the formation of the tetracationic cyclophane. Variable-temperature (1)H NMR investigation reveals that the shuttling behavior of the tetracationic ring component along the linear component is substantially influenced by the existence of the neutral ring component. The spatial repelling interaction of the neutral ring on the electron-deficient tetracationic ring simultaneously weakens the latter's "positioning" tendency at both electron-rich hydroquinone sites of the linear component. As a result, the activation energy associated with the shuttling process of the tetracationic ring between the two hydroquinone sites is remarkably reduced in comparison to that of the shuttling process of the corresponding neutral ring-free [2]rotaxanes. For the first time, the rotation of the dipyridinium subunit around the axis formed by the two methylene groups connecting them within the tetracationic cyclophane has been investigated by variable-temperature (1)H NMR spectroscopy and the associated kinetic data have also been successfully obtained. Furthermore, the UV-vis and fluorescent properties of the new [2]- and [3]rotaxanes have been studied. The results demonstrate that [3]rotaxanes with different ring components possess unique kinetic features that are not available in [3]rotaxanes with identical ring components.