OBJECTIVE:To study the therapeutic effect of L-arginine on collagen metabolism of pulmonary artery in rats with high pulmonary blood flow METHODS:The rat model of pulmonary hypertension was established with an abdominal aorta and inferior vena cava shunting L-arginine was intragastrically given to the rats with shunt in L-arginine group(1g/(kg?d)) for 11 weeks After 11 weeks of experiment,the expressions of collagen Ⅰ and collagen Ⅲ in pulmonary artery were detected by immunohistochemical assay RESULTS:The expressions of collagen Ⅰ and collagen Ⅲ in shunt group elevated obviously compared with those in control group(P

Syncope is one of the most common emergencies in the pediatric population.Autonomic -mediated reflex syncope,including postural tachycardia syndrome and vasovagal syncope,is the main cause.Although the clinical manifestations are similar,each subtype has its optimal treatment option.With the development of translational medicine in recent years,as well as the emergence of biomarkers,precision medicine has become possible,and will be the main direction in the future researches.

Hypertension in children and adolescents is defined as systolic blood pressure(SBP)and/ or dias-tolic blood pressure(DBP)≥95th percentile for age,gender and height,on at least 3 occasions. Primary hypertension is more common among children of older age or adolescents,while secondary hypertension accounts for more cases for younger children. Among causes of secondary hypertension,renovascular diseases,renal parenchymal diseases,cardio-vascular diseases,and endocrine diseases are common. An initial evaluation can be reached after history taking and physical examination,to decide whether it should be primary or secondary hypertension. Laboratory tests and procedures can further confirm the classification and etiology. There is an increase in prevalence of hypertension in children and adolescents,and an in - time diagnosis and evaluation of hypertension is important to help patients receive a better management of their conditions.

Syncope is a common clinical problem in children and adolescents. It is a major challenge for practicing physicians, and medical resource utilization and expenses associated with syncope management are enormous. A diagnostic protocol to syncope must be developed for children and adolescents for convenient and effective final diagnosis, and an analysis of cost-effectiveness is meaningful. Thus, according to the studies of syncope in children in China,the Chinese Pediatric Cardiology Society proposed the guidelines for diagnosis of syncope in children in China, and developed a simplified diagnostic protocol for children and adolescents with syncope. According to a multi-center prospective study,the diagnostic protocol in children and adolescents with syncope results in an improvement of diagnostic yield.

Myocarditis is one of the most common acquired heart diseases in children,and one of the most common causes of a pediatric dilated cardiomyopathy phenotype.The myocarditis is a difficult issue in the diagnosis and the optimal means of therapy.A recent Pediatric Cardiomyopathy Registry (PCMR) analysis in the largest group of pediatric myocarditis patients ever studied confirmed that the most common outcome in pediatric myocarditis was cardiac recovery,but approximately 30％ of pediatric myocarditis patients would die or undergo heart transplantation.Animal studies and adult experience suggested that autoimmunity might contribute to cardiac dysfunction in myocarditis.Immunosuppressive and immunomodulating therapy for pediatric myocarditis remains controversial.Small case series have shown benefit of these therapies in pediatric myocarditis.A limited number of biomarkers associated both good (recovery) and poor (death or transplantation) outcomes could be identified.We should do our best to find these biomarkers in the future.

Arrhythmia-induced cardiomyopathy (AIC) is a myocardial disease condition in which left ventricular dysfunction and cardiomegaly are induced or mediated by atrial or ventricular arrhythmias.The pathophysiological mechanisms remain unclear.Early recognition of AIC and provision of prompt treatment with pharmacological or ablative techniques could result in symptom resolution and recovery of ventricular function.But,the long-term prognosis of these patients is not clear and needs further observation and research.

Sulfur dioxide (SO_2) is an ordinary air pollutant globally and harm to human health. L-cysteine is the major sulfur-containing amino acid and its normal metabolism can produce hydrogen sulfur (H_2S) and SO_2. It is realized that H_2S has various bioactivities and is the third gasotransmitter after nitric oxide (NO) and carbon monoxide (CO). Recently, attention has been paid to the physiologic effects of endogenous SO_2 and its derivatives (bisulfite and sulfite) in vivo, and recognized that SO_2 and its derivatives can lower blood pressure, change heart rates, participate in inflammatory reactions, and so on, suggesting that endogenous SO_2 may modulate the physiologic functions in vivo as a bioactive molecule.

Objective:To constract a method of measurement microamount hydrogen sulfide (H_2S) using sensitive sulphur electrode. Methods: According to the physical and chemical characters of H_2S, H_2S, which in the fluids by mean of physical dissolve and chemical shape, is turned to sulphur ion (S 2-) by chemical responses. After the microamount of S 2- was measured by sensitive sulphur electrode, and the concentration of H_2S was converted, a method was constructed to measure the H_2S. It was used to analyze the concentrations of H_2S of plasma in rats and humans, the endogenous concentration of H_2S of cardiovascular tissue in rats, and CSE activity of cardiovascular tissues and cells. Results: The exponential regression of S 2- in the extent including 1 to 80 ?mol/L was found using sensitive sulphur electrod. The H_2S levels of plasma in male and female rats were 40?4 and 41?5 ?mol/L, respectively, and significant difference was not found; those in venous blood plasma of men and women were 33?4 ?mol/L and 35?5 ?mol/L respectively, without significant difference. There were not significant differences in the aortic endogenous levels of H_2S (24?6 and 25?5 nmol/mg pro) and myocardial levels (19?4 and 19?6 nmol/mg protein) between female and male rats. There were no different results of CSE activity in aortal tissue using sensitive sulphur electrode or traditional methods, however, the CSE activity of vascular smooth muscle cells could be accurately measured using sensitive sulphur electrode, which was difficult in using traditional method. Conclusion: The sensitive sulphur electrode assay was fit for the analysis of CSE/H_2S pathway in cardiovascular research.

Objective To explore the effect of hydrogen sulfide(H2S) on intercellular adhesion molecule-1(ICAM-1) in the pathogenesis of atherosclerosis in apoE knockout(apoE-/-) mice.Methods Six week-old C57BL/6J and apoE-/-mice were divided into control C57BL/6J group,apoE-/-group,apoE-/-+ sodium hydrosulfide(NaHS,a donor of H2S) group and apoE-/-+ DL-propargylglycine(PPG,an inhibitor of H2S synthase).There were 8 mice in each group.They were fed chow diet for 10 weeks.Serum H2S was measured by sulfide electrode-based method,serum ICAM-1 was determined by ELISA.Aortic ICAM-1 mRNA was detected by RT-PCR.The changes of atherosclerosis plaque size were observed by oil red O staining.Results Serum H2Slevel significantly decreased in apoE-/-mice(P

Aim The study was designed to explore the possible impact of sodium hydrosulfide NaHS on the content and metabolism of collagen in rats with pulmonary hypertension induced by high pulmonary blood flow. Methods Thirty-two male SD rats, weighing 140~160 g, were randomly divided into 4 groups, shunt group (n=8), shunt+NaHS group (n=8), sham group (n=8) and sham+NaHS group (n=8). Rats in shunt group and shunt+NaHS group were subjected to an abdominal aorta-inferior vena cava shunt to create an animal model of high pulmonary flow. In the sham group and sham+NaHS group, rats experienced the same experimental processes except the shunting procedure. After 11 weeks of experiment, systolic pulmonary artery pressure (SPAP) of rats was detected using a right cardiac catheterization procedure. Lung tissue hydrogen sulfide(H2S) content of rats was determined by a modified sulfide electrode method. Pulmonary artery collagen Ⅰ,collagen Ⅲ,MMP-13 and TIMP-1 protein expression of rats was investigated by immunohistochemistry.Results After 11 weeks of experiment, SPAP increased significantly, whereas lung tissue hydrogen sulfide(H2S) content decreased significantly in rats of shunt group as compared with those of sham group (P