Alternative splicing and intron retention: Their profiles and roles in cutaneous fibrosis of systemic sclerosis.

BACKGROUND: Alternative splicing (AS) and intron retention (IR) implicated in multiple pathophysiological processes, have rarely been reported in systemic sclerosis (SSc). METHODS: We integrated bulk RNA-seq and 4D label-free mass spectrometry to perform a multi-omics analysis of AS and IR in SSc skin tissue and fibroblasts. RMATS and iREAD were used to identify AS and IR, which were validated by real-time PCR. Spearman correlation and the LASSO method were employed to assess correlations among clinical features, introns, splicing factors (regulators of AS) and proteins. FINDINGS: AS profiles showed distinct alterations in SSc skin tissue, with the most pronounced changes occurring in IR. AS and IR were associated with total modified Rodnan skin score (mRSS) and local skin score. Upon TGF-ß stimulation, fibroblasts exhibited significant alterations in IR profiles, affecting genes related to fibroblast proliferation and collagen fibril organization. A comprehensive integrated analysis of introns, exons, and proteome profiles revealed that IR exerted a negative impact on protein expression, with certain changes being under intronic control. RT-PCR confirmed the presence of intron and exon-derived sequences of CTTN, OGA, MED16 and PHYKPL. Additionally, notable changes were observed in the regulatory network of splicing factors in SSc skin tissues. These factors are also involved in fibrosis pathways and correlated with clinical features. CONCLUSION: Totally, abnormal AS, IR profiles and splicing factors were identified in SSc, altered IRs and splicing factors participated in fibrosis-related pathways. IR exerted a negative impact on protein expression in TGF-ß-stimulated fibroblasts. Clarification of the IR mechanisms will provide new insights into the pathophysiology of SSc.

lncRNA­MIAT facilitates the differentiation of adipose­derived mesenchymal stem cells into lymphatic endothelial cells via the miR­495/Prox1 axis.

The development of novel treatments for lymphedema is hindered by the poorly understood pathophysiology of the disease. To improve the therapeutic success of treating the disease, the present study aimed to investigate the effects and mechanism of long non­coding RNA myocardial infarction­associated transcript (MIAT) in terms of the differentiation of adipose­derived mesenchymal stem cells (ADMSCs) into lymphatic endothelial cells (LECs). The expression levels of (MIAT), microRNA (miR)­495 and Prospero­related homeobox 1 (Prox1) were measured by reverse transcription­quantitative PCR. The protein expression levels of Prox1, lymphatic vessel endothelial hyaluronan receptor 1 (LYVE­1), vascular endothelial growth factor receptor­3 (VEGFR­3) and podoplanin (PDPL) were detected by western blotting and immunofluorescence. A dual­luciferase reporter assay was also used to detect the interaction between MIAT, miR­495 and Prox1. In addition, migration and tube­formation capabilities were measured by Transwell assay and tube­formation assay, respectively. The results obtained demonstrated that VEGF­C156S (recombinant VEGF­C in which Cys156 was replaced by Ser residue) treatment could efficiently induce the differentiation of ADMSCs into LECs. MIAT expression was upregulated and miR­495 was downregulated during differentiation. Mechanistically, MIAT upregulated Prox1 expression possibly by acting as a molecular sponge for miR­495. Functional analyses indicated that the expression levels of Prox1, LYVE­1, VEGFR­3 and PDPL, and the migration and tube­formation capabilities of ADMSCs induced by VEGF­C156S, were significantly inhibited by silencing MIAT and overexpressing miR­495. Moreover, miR­495 inhibition and Prox1 overexpression reversed the effects of MIAT downregulation and miR­495 upregulation, respectively, on the differentiation of ADMSCs into LECs. Taken together, these results suggested that MIAT may be involved in the differentiation of ADMSCs into LECs, and that the MIAT/miR­495/Prox1 axis may be a novel regulatory mechanism and therapeutic target for the treatment of lymphedema.

Modified transoral endoscopic thyroid surgery for treatment of thyroid cancer: operative steps and video.

In this video we describe a kind of modified transoral endoscopic thyroid surgery involving meticulous dissection of mental nerve. Inclusion criteria are: the diameter of benign tumors such as thyroid cyst, nodular goiter were limited less than 50 mm; the malignant thyroid tumors including follicular and papillary microcarcinoma were defined as a papillary carcinoma <2 cm in diameter and endoscopic surgery required for the patient. A 6 cm arc-shaped incision was designed at oral vestibule. The branches of mental nerves at both sides were identified and exposed carefully. A 10 mm trocar was placed at the midpoint of the vestibule. Two 5 mm trocars were separately inserted into the vestibule at lateral or medial of the medial branches of the mental nerve. Thyroidectomy and central lymph node dissection was done fully endoscopically using conventional endoscopic instruments.

Reconstruction of the Lower Abdominal Region Using Bilateral Pedicled Anterolateral Thigh Flaps Combined With Poly-Surgical Mesh: A Case Report.

The en-bloc resection of neoplasms on the abdominal wall often causes extensive defects that are difficult to manage. The anterolateral thigh (ALT) flap is a widely used flap in reconstructive surgery of defects. In this article, we present a case using bilateral pedicle anterolateral thigh flaps combined with a surgical polymesh to repair a large defect (22 cm × 18 cm) caused by dissection of a recurrent fibromatosis with good functional and aesthetic effects. There were no obvious morbidities or complications during a 6-month follow-up period.We conclude that the bilateral pedicle anterolateral thigh flap is a good choice for reconstruction of large lower abdominal wall defects. It can afford sufficient soft tissue coverage without obvious donor site morbidity.