Objective To investigate the effects of Nel-like type 1 molecule(NELL-1)on the proliferation and osteogenic differenti-ation of stem cells from human exfoliated deciduous teeth(SHEDs).Methods SHEDs was isolated,cultured,and identified.The third generation SHEDs were used for subsequent experiments.SHEDs were divided into 4 groups,and NELL-1 was added to each group at concentrations of 0(control group),50,100,and 200 ng/mL.Cell activity was measured by CCK-8 assay and crystal violet staining.The changes in osteogenic ability were detected by alkaline phosphatase activity.The expression levels of osteogenesis-related genes ALP,OCN and Runx-2 by RT-qPCR were detected.Western blot was used to detect the expression of osteogenesis-related pro-teins ALP,Runx-2 and Col-Ⅰ.Results SHEDs exhibited stem cell characteristics,and 50 ng/mL of NELL-1 protein had a promo-ting effect on SHEDs proliferation(P＜0.01).Alkaline phosphatase activity assay showed that after the addition of NELL-1,the osteo-genic effect of each group was better than that of the control group and 50 ng/mL of NELL-1 was the best(P＜0.05).RT-qPCR and Western blot results showed that 50 ng/mL of NELL-1 significantly promoted the expression of osteoblast-related genes including ALP,OCN and Runx-2 and the protein expression of ALP,Runx-2 and Col-Ⅰ(P＜0.05).Conclusion NELL-1 can promote the prolifera-tion and osteogenic differentiation of SHEDs.

Objective To investigate the effects of Nel-like type 1 molecule(NELL-1)on the proliferation and osteogenic differenti-ation of stem cells from human exfoliated deciduous teeth(SHEDs).Methods SHEDs was isolated,cultured,and identified.The third generation SHEDs were used for subsequent experiments.SHEDs were divided into 4 groups,and NELL-1 was added to each group at concentrations of 0(control group),50,100,and 200 ng/mL.Cell activity was measured by CCK-8 assay and crystal violet staining.The changes in osteogenic ability were detected by alkaline phosphatase activity.The expression levels of osteogenesis-related genes ALP,OCN and Runx-2 by RT-qPCR were detected.Western blot was used to detect the expression of osteogenesis-related pro-teins ALP,Runx-2 and Col-Ⅰ.Results SHEDs exhibited stem cell characteristics,and 50 ng/mL of NELL-1 protein had a promo-ting effect on SHEDs proliferation(P＜0.01).Alkaline phosphatase activity assay showed that after the addition of NELL-1,the osteo-genic effect of each group was better than that of the control group and 50 ng/mL of NELL-1 was the best(P＜0.05).RT-qPCR and Western blot results showed that 50 ng/mL of NELL-1 significantly promoted the expression of osteoblast-related genes including ALP,OCN and Runx-2 and the protein expression of ALP,Runx-2 and Col-Ⅰ(P＜0.05).Conclusion NELL-1 can promote the prolifera-tion and osteogenic differentiation of SHEDs.

Single-cell transcriptome sequencing (scRNA-seq) can resolve the expression characteristics of cells in tissues with single-cell precision, enabling researchers to quantify cellular heterogeneity within populations with higher resolution, revealing potentially heterogeneous cell populations and the dynamics of complex tissues. However, the presence of a large number of technical zeros in scRNA-seq data will have an impact on downstream analysis of cell clustering, differential genes, cell annotation, and pseudotime, hindering the discovery of meaningful biological signals. The main idea to solve this problem is to make use of the potential correlation between cells and genes, and to impute the technical zeros through the observed data. Based on this, this paper reviewed the basic methods of imputing technical zeros in the scRNA-seq data and discussed the advantages and disadvantages of the existing methods. Finally, recommendations and perspectives on the use and development of the method were provided.
Cluster Analysis ; Transcriptome

Objective To investigate the clinical effect of low molecular weight heparin calcium (MvH) in the treatment of acute exacerbation of chronic obstructive pulmonary disease(AECOPD)complicated with pulmonary heart disease. Methods 128 AECOPD patients with pulmonary heart disease from January 2016 to December 2016 in our hospital were randomly divided into observation group and control group in equal number by random digit table with EXCEL2007. Apart from the basic treatment like anti infection,oxygen,expectorant,maintenance of water and electrolyte balance and cardiotonic treatment ,the observation group was treated with MvH. The two groups were compared in terms of pre-and post-ventricular end diastolic volume(EDV),end systolic volume(ESV),right ventricular ejection fraction(RVEF),pulmonary artery acceleration time(AT),arterial oxygen pressure(PaO2),arterial partial pressure of carbon dioxide(PaCO2),pH value,whole blood viscosity at low shear the whole blood viscosity at high shear rate,plasma viscosity,hematocrit,plasma D- dimer(D-D). Results After treatment,EDV and ESV of the observation group were significantly lower than the control group (P < 0.05)and RVEF and AT were higher than the control group(P < 0.05). PaCO2 was lower than that of the control group(P < 0.05). PaO2,pH values were higher than those of the control group(P < 0.05). After treatment,the whole blood viscosity,whole blood low shear viscosity at high shear rate,plasma viscosity,hematocrit, plasma level of D-D of the observation group were all lower than those of the control group (P < 0.05). Conclusion Subcutaneous injection with MvH to treat the patients with AECOPD complicated with pulmonary heart disease can improve the blood rheology and improve heart function and blood gas level.

Objective To observe the influence of insulin resistance(IR) and isosorbide mononitrate(ISMN) on myocardial cellular apoptosis in spontaneously hypertensive rats (SHR) .Methods Forty male 14‐week old Wistar(W) rats and SHR(S) each were respectively or jointly fed with normal diet (ND) ,high fat and high glucose(HFHG) diet ,normal saline(NS)and ISMN by ga‐vage .Then they were randomly divided into the normal and NS group (normal W and normal S ) ,HFHG and NS group(HFHG W and HFHG S) ,normal and ISMN group(ISMN W and ISMN S) ,HFHG and ISMN group(HI W and HI S) ,with 10 rats in each group .After 12‐week feeding ,carotid arterial blood was collected for detecting blood glucose concentration and insulin level and cal‐culating insulin resistance index (HOMA‐IR);4 myocardial tissue samples were taken for respectively observing the morphology under microscope ,and detecting the NO level ,myocardial Bcl‐2 ,Bax gene and their protein expression levels in myocardial tissue . Results Myocardial NO level ,Bax gene mRNA and related protein levels in the HFHG and ISMN intervention groups were higher than those in the normal group ,while the bcl‐2 gene mRNA and related protein expression were on the contrary ;myocardial tissue NO level ,Bax gene mRNA and related protein expression in the S groups were increased compared with the corresponding W groups ,while the bcl‐2 gene mRNA and related protein expression were on the contrary ;in the HFHG W group ,the myocardial tis‐sue NO level had significantly positive correlation with HOMA‐IR ,and in the ISMN W group ,HOMA‐IR was positively correlated with the NO level in the myocardial tissue .Conclusion Myocardial cellular apoptosis of SHR is increased compared with Wistar rats ;both IR and ISMN can aggravate the apoptosis of SHR myocardial cells ,moreover IR has a mutual induction and reciprocal causation with ISMN .