1.The value of T2 signal intensity in DTI to differentiate between brain tumor infiltration and pure vasogenic edema
Zhigang MIN ; Ming ZHANG ; Chen NIU ; Long XU ; Wenchao XIE
Journal of Practical Radiology 2017;33(11):1665-1667,1674
Objective To explore the added value of T2-signal intensity (T2-SI) in discriminating tumor-infiltration from pure vasogenic edema with diffusion tensor imaging (DTI).Methods 55 patients with brain tumors [28 with high-grade glioma (HGG),13 with meningioma,and 14 with metastases] and concurrent peritumoral edema were scanned with DTI.The mean fractional anisotropy (FA),mean diffusivity (MD),longitudinal diffusivity (λ//) and radial diffusivity (λ⊥) in peritumoral edema of different tumors were measured and compared with each other.Results Only the mean FA showed significant difference between edema of HGG and meningioma (P<0.05).When standardized T2-SI was used as the covariant,FA and λ⊥ showed significant differences among the tumor groups.The adjusted FA in edema of HGG was significantly lower than that of metastases (P<0.05) and meningioma (P< 0.001).The adjusted λ⊥ in edema of HGG was significantly higher than that of meningioma (P<0.05).Conclusion By controlling the effect of T2-SI,the value of DTI in distinguishing tumor-infiltration from pure vasogenic edema could be improved.
2.Role of dermoscopy in assessing vitiligo activity
Chao FU ; Jiaona WU ; Wenchao LANG ; Fei GAO ; Guiye NIU ; Peiwen BIAN ; Minhong GAO ; Xiaoqing SI ; Linlin XIN
Chinese Journal of Dermatology 2022;55(3):268-271
With in-depth research and development of dermoscopy, the dermoscopic features including perifollicular pigments, perilesional pigments, pigment network structure, satellite phenomenon and "tapioca sago" appearance, micro-Koebner phenomenon and comet tail-like phenomenon have provided a basis for the evaluation of vitiligo activity. This review summarizes progress in the evaluation of vitiligo activity with dermoscopy in recent years, aiming to promote the application of dermoscopy in the assessment of vitiligo activity.
3.Acrylamide fragment inhibitors that induce unprecedented conformational distortions in enterovirus 71 3C and SARS-CoV-2 main protease.
Bo QIN ; Gregory B CRAVEN ; Pengjiao HOU ; Julian CHESTI ; Xinran LU ; Emma S CHILD ; Rhodri M L MORGAN ; Wenchao NIU ; Lina ZHAO ; Alan ARMSTRONG ; David J MANN ; Sheng CUI
Acta Pharmaceutica Sinica B 2022;12(10):3924-3933
RNA viruses are critically dependent upon virally encoded proteases to cleave the viral polyproteins into functional proteins. Many of these proteases exhibit a similar fold and contain an essential catalytic cysteine, offering the opportunity to inhibit these enzymes with electrophilic small molecules. Here we describe the successful application of quantitative irreversible tethering (qIT) to identify acrylamide fragments that target the active site cysteine of the 3C protease (3Cpro) of Enterovirus 71, the causative agent of hand, foot and mouth disease in humans, altering the substrate binding region. Further, we re-purpose these hits towards the main protease (Mpro) of SARS-CoV-2 which shares the 3C-like fold and a similar active site. The hit fragments covalently link to the catalytic cysteine of Mpro to inhibit its activity. We demonstrate that targeting the active site cysteine of Mpro can have profound allosteric effects, distorting secondary structures to disrupt the active dimeric unit.
4.LncRNA DACH1 protects against pulmonary fibrosis by binding to SRSF1 to suppress CTNNB1 accumulation.
Jian SUN ; Tongzhu JIN ; Zhihui NIU ; Jiayu GUO ; Yingying GUO ; Ruoxuan YANG ; Qianqian WANG ; Huiying GAO ; Yuhan ZHANG ; Tianyu LI ; Wenxin HE ; Zhixin LI ; Wenchao MA ; Wei SU ; Liangliang LI ; Xingxing FAN ; Hongli SHAN ; Haihai LIANG
Acta Pharmaceutica Sinica B 2022;12(9):3602-3617
Idiopathic pulmonary fibrosis (IPF) is a progressive disease with unknown etiology and limited therapeutic options. Activation of fibroblasts is a prominent feature of pulmonary fibrosis. Here we report that lncRNA DACH1 (dachshund homolog 1) is downregulated in the lungs of IPF patients and in an experimental mouse model of lung fibrosis. LncDACH1 knockout mice develop spontaneous pulmonary fibrosis, whereas overexpression of LncDACH1 attenuated TGF-β1-induced aberrant activation, collagen deposition and differentiation of mouse lung fibroblasts. Similarly, forced expression of LncDACH1 not only prevented bleomycin (BLM)-induced lung fibrosis, but also reversed established lung fibrosis in a BLM model. Mechanistically, LncDACH1 binding to the serine/arginine-rich splicing factor 1 (SRSF1) protein decreases its activity and inhibits the accumulation of Ctnnb1. Enhanced expression of SRSF1 blocked the anti-fibrotic effect of LncDACH1 in lung fibroblasts. Furthermore, loss of LncDACH1 promoted proliferation, differentiation, and extracellular matrix (ECM) deposition in mouse lung fibroblasts, whereas such effects were abolished by silencing of Ctnnb1. In addition, a conserved fragment of LncDACH1 alleviated hyperproliferation, ECM deposition and differentiation of MRC-5 cells driven by TGF-β1. Collectively, LncDACH1 inhibits lung fibrosis by interacting with SRSF1 to suppress CTNNB1 accumulation, suggesting that LncDACH1 might be a potential therapeutic target for pulmonary fibrosis.