Efficacy and safety of umbilical cord mesenchymal stem cells for the treatment of patients with COVID-19

OBJECTIVES: The coronavirus disease (COVID-19) outbreak has catastrophically threatened public health worldwide and presented great challenges for clinicians. To date, no specific drugs are available against severe acute respiratory syndrome coronavirus 2. Mesenchymal stem cells (MSCs) appear to be a promising cell therapy owing to their potent modulatory effects on reducing and healing inflammation-induced lung and other tissue injuries. The present pilot study aimed to explore the therapeutic potential and safety of MSCs isolated from healthy cord tissues in the treatment of patients with COVID-19. METHODS: Twelve patients with COVID-19 treated with MSCs plus conventional therapy and 13 treated with conventional therapy alone (control) were included. The efficacy of MSC infusion was evaluated by changes in oxygenation index, clinical chemistry and hematology tests, immunoglobulin (Ig) levels, and pulmonary computerized tomography (CT) imaging. The safety of MSC infusion was evaluated based on the occurrence of allergic reactions and serious adverse events. RESULTS: The MSC-treated group demonstrated significantly improved oxygenation index. The area of pulmonary inflammation decreased significantly, and the CT number in the inflammatory area tended to be restored. Decreased IgM levels were also observed after MSC therapy. Laboratory biomarker levels at baseline and after therapy showed no significant changes in either the MSC-treated or control group. CONCLUSION: Intravenous infusion of MSCs in patients with COVID-19 was effective and well tolerated. Further studies involving a large cohort or randomized controlled trials are warranted.

Clinicopathological analysis of endoscopic submucosal dissection for esophageal mucosa lesion / 中国内镜杂志

Objective To analyze the endoscopic and clinicopathologic features of early esopheal carcinoma and precancerous lesions and evaluate the necessity, efficacy and safety of ESD in the treatment. Methods From May 2013 to April 2016, 51 consecutive patients underwent high-resolution video endoscopy and biopsy, confirmed diagnosis of early esophageal squamous cell carcinoma or intraepithelial neoplasia were included. There were capillary loops (IPCL), iodine-staining, preoperative and postoperative pathology, and complications to analyze. Results 51 patients had total 58 lesions, Type A, Type B1, Type B2 of IPCL classification were diagnosed in 8 (13.79%), 44 (75.86%), 6 (10.34%). Low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia, early esophageal carcinoma of preoperative biopsy were diagnosed in 11 (18.97%), 42 (72.41%), 5 (8.62%), low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia, early esophageal carcinoma of postoperative pathology results were diagnosed in 10 (17.54%), 27 (46.55%), 21 (36.21%), concordance rate of pathological results were 60.34%. Complications included micro-perforations (0.00%), strictures (8.62%) and delayed hemorrhage (3.51%), respectively. Conclusion After endoscopic submucosal dissection, detection rate of early esophageal cancer increased significantly, preoperative biopsy had guidance significance in diagnosis and treatment, ESD treatment can reduce the missed diagnosis of early esophageal carcinoma.

Clinicopathological analysis of endoscopic submucosal dissection for esophageal mucosa lesion / 中国内镜杂志

Objective To analyze the endoscopic and clinicopathologic features of early esopheal carcinoma and precancerous lesions and evaluate the necessity, efficacy and safety of ESD in the treatment. Methods From May 2013 to April 2016, 51 consecutive patients underwent high-resolution video endoscopy and biopsy, confirmed diagnosis of early esophageal squamous cell carcinoma or intraepithelial neoplasia were included. There were capillary loops (IPCL), iodine-staining, preoperative and postoperative pathology, and complications to analyze. Results 51 patients had total 58 lesions, Type A, Type B1, Type B2 of IPCL classification were diagnosed in 8 (13.79%), 44 (75.86%), 6 (10.34%). Low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia, early esophageal carcinoma of preoperative biopsy were diagnosed in 11 (18.97%), 42 (72.41%), 5 (8.62%), low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia, early esophageal carcinoma of postoperative pathology results were diagnosed in 10 (17.54%), 27 (46.55%), 21 (36.21%), concordance rate of pathological results were 60.34%. Complications included micro-perforations (0.00%), strictures (8.62%) and delayed hemorrhage (3.51%), respectively. Conclusion After endoscopic submucosal dissection, detection rate of early esophageal cancer increased significantly, preoperative biopsy had guidance significance in diagnosis and treatment, ESD treatment can reduce the missed diagnosis of early esophageal carcinoma.

A simple, rapid and economic method for detecting multidrug-resistant tuberculosis

OBJECTIVE: To evaluate multiplex allele specific polymerase chain reaction as a rapid molecular tool for detecting multidrug-resistant tuberculosis. METHODS: Based on drug susceptibility testing, 103 isolates were multidrug-resistant tuberculosis and 45 isolates were sensitive to isonicotinylhydrazine and rifampin. Primers were designed to target five mutations hotspots that confer resistance to the first-line drugs isoniazid and rifampin, and multiplex allele specific polymerase chain reaction was performed. Whole-genome sequencing confirmed drug resistance mutations identified by multiplex allele specific polymerase chain reaction. RESULTS: DNA sequencing revealed that 68.9% of multidrug-resistant strains have point mutations at codon 315 of the katG gene, 19.8% within the mabA-inhA promoter, and 98.0% at three hotspots within rpoB. Multiplex allele specific polymerase chain reaction detected each of these five mutations, yielding 82.3% sensitivity and 100% specificity for isoniazid resistance, and 97.9% sensitivity and 100% specificity for rifampin resistance as compared to drug susceptibility testing. CONCLUSIONS: The results show that multiplex allele specific polymerase chain reaction is an inexpensive and practical method for rapid detection of multidrug-resistant tuberculosis in developing countries.

Co-culture of Mesenchymal Stem Cells with Umbilical Vein Endothelial Cells under Hypoxic Condition / 华中科技大学学报（医学）（英德文版）

By co-culturing humm mesenchymal stem cells (hMSCs) and human umbilical rein endothelial cells (HUVECs) under hypoxia and creating a microenvironment similar to that of transplanted hMSCs for the treatment of avascular ni ANFH,the effect of hMSCs on survival,apoptosis,migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) under the hypoxic condition were investigated in vitro.hMSCs and HUVECs were cultured and identified in vitro.Three kinds of conditioned media,CdM-CdMNOR,CdM-CdMHYP and HUVEC-CdMHYP were prepared.HUVECs were cultured with these conditioned media under hypoxia.The survival rate,apoptosis rate,migration and angiogenesis of HUVECs were respectively detected by CCK-8,flow cytometry,Transwell and tube formation assay.The content of SDF-1α,VEGF and IL-6 in CdM was determined by ELISA.Our results showed that hMSCs and HUVECs were cultured and identified successfully.Compared with MSC-CdMNOR and HUVEC-CdMHYP groups,the survival rate,migration and angiogenesis of HUVECs in MSC-CdMHYP group were significantly increased while the apoptosis rate was declined (P＜0.05).Moreover,the expression of SDF-1a VEGF and IL-6 in MSC-CdMHYP group was up-regulated.Under hypoxia,the apoptosis of HUVECs was inhibited while survival,migration and angiogenesis were improved by co-culture of hMSCs and HUVECs.The underlying mechanism may be that hMSCs could secrete a number of cytokines and improve niche,which might be helpful in the treatment of femoral head necrosis.

Specific Inhibitory Protein Dkk-1 Blocking Wnt/β-catenin Signaling Pathway Improve Protectives Effect on the Extracellular Matrix / 华中科技大学学报（医学）（英德文版）

The present study examined the role of Wnt/β-catenin signaling pathway in the degeneration of nucleus pulposus cells and the protective effect of DKK1 on nucleus pulposus cells.The model of nucleus pulposus cell degeneration was induced by intra-disc injection of TNF-α,and the expression of β-catenin protein was detected by Western blotting.The cultured rabbit nucleus pulposus cells were divided into 4 groups.In group A,the cells were cultured with normal medium and served as control group.In group B,the cells were cultured with TNF-α and acted as degeneration group.In group C,the cells were cultured with TNF-α and transfected with Adv-eGFP and was used as fluorescence control group.In group D,the cells were cultured with TNF-α and transfected with Adv-hDKK1-eGFP,serving as intervention group.The expression of type Ⅱ collagen,proteoglycan,β-catenin,and MMP-13 in each group was detected by immunocytochemistry and RT-PCR.The result showed that TNF-α increased the expression of β-catenin and MMP-13,and significantly inhibited the synthesis of type Ⅱ collagen and proteoglycan,which resulted in the degeneration of nucleus pulposus cells.This effect could be obviously reversed by DKK1.We are led to concluded that TNF-α could activate the Wnt/β-catenin signaling pathway,and increase the expression of MMP-13,thereby resulting in disc degeneration.Specifically blocking Wnt/β-catenin signaling pathway by DKK-1 could protect the normal metabolism of intervertebral disc tissue.The Wnt pathway plays an important role in the progression of the intervertebral disc degeneration.