Objective
To explore the management strategies of type Ⅰ esophageal atresia (EA) through natural growth and tension-extension.
Methods
From January 2012 to January 2017, a total of 10 children of type-Ⅰ EA were recruited.There were 5 boys and 5 girls.Difficult postnatal insertion of gastric tube prompted a clinical diagnosis of type-Ⅰ EA after esophagography.Within a month after birth, laparoscopic gastrostomy was performed.During operation, the distance between proximal and distal esophagus was measured on esophageal radiography.And nutrient liquid was supplied via gastrostomy.Saliva was reabsorbed through proximal esophagus and esophageal growth measured regularly.Esophageal extension was achieved through natural growth and tension-extension.Thus thoracoscopic gastroesophagostomy was delayed.
Results
Two cases of thoracoscopic esophageal anastomosis were achieved through natural growth.The completion ages were 153 and 151 days respectively.In another eight cases, the distance between proximal and distal esophagus was still greater than the total length of four vertebrates at 12 weeks post-birth.Tension-extension was applied for promoting the growth of esophagus and thoracoscopic gastroesophagostomy performed .And esophagectasia was performed postoperatively for counteracting esophageal stenosis.When starting endo-esophogeal lengthening, the mean age was (174.3±86.6) (92-280) days and the mean vertebral number between esophogeal ends (5.1±0.5)(4.5-6.0). And the extended time was (49.0±16.2) (28-69) days.At Day 7 postoperatively, esophogeal contrasting radiography revealed esophogeal anastomotic fistula (n=2). Both cases were cured after conservative measures.Esophogeal stenosis of varying degrees (n=10) required esophogeal dilatation.During follow-ups, all children had excellent growth and development.
Conclusions
Promoting esophageal extension through natural growth and tension-extension reduces pre-anastomotic surgical trauma and postoperative adhesion.Thoracoscope allows a distinct exsanguine operative field for minimizing surgical trauma.The recovery is satisfactory after treatment.This promising treatment is worth a wider popularization.
Key words:
Esophageal atresia; Thoracoscopes; Esophageal extension
Abstract Background Existing methods for in vitro differentiation of human pluripotent stem cells (hPSCs) into sinoatrial node-like cells (SANLCs) require complex and undefined medium constituents. This might hinder the elucidation of the molecular mechanisms involved in cardiac subtype specification and prevent translational application. In our study, we aimed to establish a chemically defined differentiation methods to generate SANLCs effectively and stably. Methods We induced human embryonic stem cells (hESCs)/induced PSCs (hiPSCs) to pan-cardiomyocytes by temporal modulation of the WNT/β-catenin (WNT) signaling pathway with GSK3 inhibitor and WNT inhibitor. During cardiac mesoderm stage of the differentiation process, signaling of WNT, retinoid acid (RA), and fibroblast growth factor (FGF) was manipulated by three specific molecules. Moreover, metabolic selection was designed to improve the enrichment of SANLCs. Finally, RT-PCR, immunofluorescence, flow cytometry, and whole cell patch clamp were used to identify the SANLCs. Results WNT, RA, and FGF signaling promote the differentiation of hPSCs into SANLCs in a concentration- and time window-sensitive manner, respectively. Synergetic modulation of WNT, FGF, and RA signaling pathways enhance the pacemaker phenotype and improve the differentiation efficiency of SANLCs (up to 45%). Moreover, the purification based on lactate metabolism and glucose starvation further reached approximately 50% of SANLCs. Finally, the electrophysiological data demonstrate that cells differentiated with the proposed protocol produce a considerable number of SANLCs that display typical electrophysiological characteristics of pacemaker cells in vitro. Conclusion We provide an optimized and chemically defined protocol to generate SANLCs by combined modulation of WNT, RA, and FGF signaling pathways and metabolic selection by lactate enrichment and glucose starvation. This chemically defined method for generating SANLCs might provide a platform for disease modeling, drug discovery, predictive toxicology, and biological pacemaker construction.
The ISL LIM homeobox 1 (ISL1) gene belongs to the LIM/homeodomain transcription factor family and plays a pivotal role in conveying multipotent and proliferative properties of cardiac precursor cells. Mutations in ISL1 are linked to congenital heart disease. To further explore ISL1's role in the human heart, we have created a homozygous ISL1 knockout (ISL1-KO) human embryonic stem cell line using the CRISPR/Cas9 system. Notably, this ISL1-KO cell line retains normal morphology, pluripotency, and karyotype. This resource serves as a valuable tool for investigating ISL1's function in cardiomyocyte differentiation.
Normal cardiac automaticity is dependent on the pacemaker cells of the sinoatrial node (SAN). Insufficient cardiac pacemaking leads to the development of sick sinus syndrome (SSS). Since currently available pharmaceutical drugs and implantable pacemakers are only partially effective in managing SSS, there is a critical need for developing targeted mechanism-based therapies to treat SSS. SAN-like pacemaker cells (SANLPCs) are difficult to regenerate in vivo or in vitro because the genes and signaling pathways that regulate SAN development and function have not been fully elucidated. The development of more effective treatments for SSS, including biological pacemakers, requires further understanding of these genes and signaling pathways. Compared with genetic models and bulk RNA sequencing, single-cell RNA sequencing (scRNA-seq) technology promises to advance our understanding of cellular phenotype heterogeneity and molecular regulation during SAN development. This review outlines the key transcriptional networks that control the structure, development, and function of the SAN, with particular attention to SAN markers and signaling pathways detected via scRNA-seq. This review offers insights into the process and transcriptional network of SAN morphogenesis at a single-cell level and discusses current challenges and potential future directions for generating SANLPCs for biological pacemakers.
Long noncoding RNAs (lncRNAs) are potential regulators of a variety of cardiovascular diseases. Therefore, there is a series of differentially expressed lncRNAs in pulmonary arterial hypertension (PAH) that may be used as markers to diagnose PAH and even predict the prognosis. However, their specific mechanisms remain largely unknown. Therefore, we investigated the biological role of lncRNAs in patients with PAH. First, we screened patients with PAH secondary to ventricular septal defect (VSD) and those with VSD without PAH to assess differences in lncRNA and mRNA expression between the two groups. Our results revealed the significant upregulation of 813 lncRNAs and 527 mRNAs and significant downregulation of 541 lncRNAs and 268 mRNAs in patients with PAH. Then, we identified 10 hub genes in a constructed protein-protein interaction network. Next, we performed bioinformatics analyses, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis and subsequently constructed coding-noncoding co-expression networks. We screened lncRNA-TCONS_00008552 and lncRNA-ENST00000433673 as candidate genes and verified the expression levels of the lncRNAs using quantitative reverse-transcription PCR. Although expression levels of lncRNA-TCONS_00008552 in the plasma from the PAH groups were significantly increased compared with the control groups, there was no significant difference in the expression of lncRNA-ENST00000433673 between the two groups. This study bolsters our understanding of the role of lncRNA in PAH occurrence and development and indicates that lncRNA-TCONS_00008552 is a novel potential molecular marker for PAH.
The DDT1 MF2 smooth muscle tumor cell line was derived from an estrogen/androgen-induced leiomyosarcoma that arose in the ductus deferens of a Syrian hamster. The growth of this cell line is arrested at the G0/G1 phase of the cell cycle after treatment with glucocorticoids. To identify the putative gene(s) that are potentially involved in this hormone-induced cell growth arrest, we have used a differential screening technique to clone those genes whose expression is induced or up-regulated by glucocorticoids. A number of glucocorticoid response genes were thereby isolated from the leiomyosarcoma cells. One of these clones, termed TA16, was found to be markedly up-regulated by glucocorticoids in DDT1 MF2 cells, but only marginally changed in GR1 cells, a glucocorticoid-resistant variant that was selected from the wild type DDT1 MF2 cell. Isolation and sequencing of its intact cDNA indicated that the TA16 encodes a protein 485 amino acids long, and its sequence is closely homologous to a novel transcriptional repressor that presumably represses the transcription activity of some zinc finger transcriptional factors through a direct interaction. Transfection assays demonstrated that introduction of an antisense TA16 cDNA expression vector, controlled by an MMTV promoter, into the DDT1 MF2 cell significantly relieved the glucocorticoid-induced cell growth arrest. This finding suggests that TA16 might participate in the mediation of glucocorticoid-induced cell cycle arrest in leiomyosarcoma cells.