The year of 2019 is memorable,because it ushers in the seventieth anniversary of the founding of China.We have witnessed tremendous changes in our motherland and also a rising China.On this occasion,from the perspective of a pediatrician,I reviewed the Chinese standards for childhood brain death that I have participated in the manuscript preparation,compared the differences of the guidelines at home and abroad,and looked forward to the future development.The criteria for determining child brain death in China have gradually developed,and are generally more prudent and strict compared with foreign standards.There are differences in applicable populations,auxiliary examination requirements,intervals between two repeated judgments and the qualification requirements for doctors.Through this review,the author discusses the differences,advantages and disadvantages between domestic and foreign guidelines,and looks forward to the future development.

Myocarditis refers to diffuse or focal inflammatory cell infiltration of the myocardial interstitium and necrosis or degeneration of adjacent myocardial fiber caused by infection or other causes,which is one of the common diseases that cause the death of infants and adolescents.Viral infection is the main pathogenic factor,but the pathogenesis of myocarditis has not yet been fully elucidated.Autophagy is a highly conservative process of self-digestion,which can provide amino acids,ATP and other substances for cells in the state of inflammation or starvation to help cells survive the energy crisis under excessive stimulation.However,excessive autophagy can promote the replication of viruses,which leads to autophagic death.In recent years,some researchers found that autophagy is closely related to the process of viral myocarditis associated with Coxsackie virus B3.The role of autophagy in the pathogenesis of myocarditis is reviewed in this article.

Methylmalonic acidemia is the most common disease of congenital organic acid metabolic disorders,and it is an autosomal recessive disease.The clinical manifestations of methylmalonic acidemia are non-specific.It is characterized by the neurological symptoms.Cardiovascular diseases have little been associated with methylmalonic acidemia.But,cardiovascular diseases including structural heart disease,pulmonary hypertension,cardiomyopathy,hypertension,arrhythmias,may cause rapid deterioration,or even sudden death.This paper is a review of cardiovascular diseases of methylmalonic acidemia.

Congenital heart disease (CHD) is the most common congenital malformation and also one of the common causes of heart failure in children.At present,the clinical diagnosis of heart failure in children mainly depends on the medical history,symptoms and signs,with strong subjectivity and lack of timely and simple objective criteria,which are easy to be missed.Brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-ProBNP) are polypeptides synthesized and secreted by ventricular myocytes,which have good sensitivity to reflect ventricular systolic,diastolic function and pre-and post-load.They have been widely used in various cardiovascular diseases.In recent years,many studies have shown that the plasma concentration of the two can be used to guide perioperative surgical treatment and evaluate the perioperative prognosis risk of children with CHD.This article reviews the application of BNP and NT-ProBNP in children with CHD with heart failure,especially during perioperative period.

When the pathogen infects the fetus,the pathogenic microorganism and the infection product are recognized by the corresponding receptor.The fetus innate immune system is passively activated,which produces proinflammatory cytokines,induces cascade reaction of cytokines,and releases a large number of inflammatory factors secreted by the body.Its toxic effect can cause damage to the brain,lung,small intestine and heart and other important organs of the whole body,which seriously threatens the life of the perinatal infants and their subsequent survival quality.It has been found that fetal cardiovascular system is one of the important target organs of intrauterine infection.Cytokines produced by cardiac inflammation and induced by intrauterine infection can damage myocardial cells,affect the proliferation of myocardial cells,and cause damage to cardiac function.Moreover,the persistent influence of infection on fetus leads to fetal vascular remodeling and changes in fetal cardiopulmonary hemodynamics.This article reviews the effects of pathogens of intrauterine infection and fetal cardiac inflammation,cardiac hemodynamics,cardiomyocyte development,gene program of cardiomyocyte and cardiac structure development on fetal cardiovascular system.

Pulmonary arterial hypertension (PAH) is a multifactorial pulmonary vascular disease accompanied by abnormal increase of pulmonary artery pressure with complicated pathogenesis,which leads to progressive right heart failure and death.It is necessary to establish an animal model that can simulate the pathophysiological characteristics of PAH in order to study the pathogenesis of PAH further.Animal models of PAH act as effective methods to study the pathogenesis,pathophysiology,development,prognosis and treatment of PAH.Classic PAH models include chronically hypoxia,drug injection,and so forth.Although animal models of PAH differ from each other,there is still no widely accepted animal model which can totally imitate human PAH.This review summarizes animal models of PAH in order to provide reference for choosing experimental animals of PAH and to establish a better animal model similar to human PAH.

In recent years,the global situation of tuberculosis disease has deteriorated sharply,and the susceptibility of host to mycobacterium tuberculosis is heterogeneous.Therefore,polymorphism of gene loci plays an important role in the susceptibility to tuberculosis.Vitamin D receptor (VDR) gene has been confirmed as one of the major candidate genes for genetic susceptibility to tuberculosis.The four well-studied major sites are Foki,Bsmi,Apai and Taqi.However,the specific mechanism by which polymorphism affects the occurrence and development of tuberculosis has not been fully elucidated.There is considerable controversy about the relationship between VDR gene polymorphism and tuberculosis susceptibility,mainly due to the interaction between environment and genes,racial differences,etc.This article reviews the polymorphism of VDR gene and its effect on host infected tuberculosis.

Clostridium difficile (CD),a gram-positive,spore-forming,obligate anaerobic bacillus,is a leading cause of antibiotic-associated diarrhea (AAD) worldwide.With the widespread use of broad-spectrum antibiotics,the incidence of clostridium difficile infection in children is rising,while recurrent clostridium difficile infection (RCDI) requires prolonged treatment and higher medical costs.Malignancy,recent surgery and antibiotic exposures have been identified as the risk factors in children.While the toxigenic strains culture and the cell cytotoxicity neutralization assay are gold standard for the diagnosis,new diagnostic approaches such as nucleic acid amplification method have become available.The use of antibiotics,fecal microbiota transplantation (FMT) or monoclonal antibodies are included in the current treatments for RCDI.This review will cover published studies to discuss the risk factors,diagnosis and treatment of RCDI in children.

With the development and popularization of endoscopic techniques,the application of pediatric colonoscopy has increased rapidly.Numerous studies have evaluated efficacy and safety of different bowel preparation regimens,however there is a lack of standard protocols of bowel preparation for pediatric colonoscopy.Bowel-cleansing agents,which can be divided into osmotic and stimulant laxatives according to mechanism of action,play an important role in bowel preparation.Efficacy,tolerability,compliance and safety are important factors for evaluation of bowel-cleansing agents.Selection of bowel-cleansing agents in clinical practice should take into account patients' underlying disease and characteristics of medications.This review is mainly focused on bowel preparation for pediatric colonoscopy based on the common bowel cleansing agents and their efficiency evaluation.

The medial temporal lobe epilepsy with hippocampal sclerosis is one of the most common drug resistant epilepsy,which involves complex neural networks and often requires surgical treatment.Studies have shown that it is related to the history of febrile convulsions,however,the further research is needed.Therefore,it is particularly important to accurately identify hippocampal sclerosis and guide clinical treatment.In this paper,the classification of hippocampal sclerosis was summarized,and the possible mechanism of hippocampal sclerosis was explored in terms of cationic-chloride co-transporters,glutamate and its receptors,and changes in expression of mRNA.The characteristics of magnetic resonance,magnetic resonance spectroscopy and PET of hippocampal sclerosis were listed to provide evidence for early recognition of hippocampal sclerosis.In theory,it provides ideas for further prevention of hippocampal sclerosis and improvement of quality of life in patients with medial temporal lobe epilepsy and hippocampal sclerosis.