Abstract The popularization of the use of electronic has become a global trend, and children are exposed to devices at younger ages. A large proportion of children and adolescents spend on screen time more than 2 h which is recommended in most guidelines. The paper reviews possible effects of screen time on physical and mental health, as well as mental disorders in children and adolescents. It is found that excessive screen time showed negative impacts on mental health, including depression, anxiety, mood disorder, social adaptational problems, behavioral disorders, self injurious behaviors, and health risk behaviors. Much attention has been paid on the association between excessive screen time and mental health of children and adolescents, while possible mechanisms and influencing factors are lacking. Effective intervention studies are needed to provide a basis for child and adolescent health promotion.

Objective:To explore the application effect of structural formula based continuous nursing in colorectal cancer patients with ostomy.Methods:Using the convenient sampling method, a total of 128 patients with colorectal cancer stoma who were admitted to Liuzhou Worker's Hospital from July 2019 to September 2021 were selected as the research objects. According to the random number table method, they were divided into the observation group and the control group, with 64 cases in each group. Patients in the observation group received structural continuous nursing, while patients in the control group received traditional continuous care. Exercise of Self-Care Agency Scale (ESCA) and the Medical Outcomes 36-items Short Form Health Survey (SF-36) scores were compared between the two groups.Results:After 3 months of intervention, ESCA and SF-36 scores in the observation group were higher than those in the control group, and the differences were statistically significant ( P<0.05) . Conclusions:Structural formula based continuous nursing can improve the self-care ability and quality of life of colorectal cancer patients with ostomy.

BACKGROUND: Studies have shown that umbilical cord mesenchymal stem cells are ideal seed cells for tissueengineering research.OBJECTIVE: To isolate, culture and identify tree shrew umbilical cord mesenchymal stem cells, in order toestablish a standardized tree shrew umbilical cord mesenchymal stem cell lines.METHODS: Caesarean-isolated tree shrew umbilical cord samples were used to isolate and culture umbilical cordmesenchymal stem cells using tissue explant adherent method. Flow cytometry assay was used to detect cellsurface markers. Osteogenic and adipogenic induction media were used to induce umbilical cord mesenchymalstem cells to differentiate into osteoblasts and adipocytes.RESULTS AND CONCLUSION: The cultured umbilical cord mesenchymal stem cells expressed CD90 and CD105 with the positive rate of 99.9% and 99.8% respectively. Hematopoietic stem cell marker CD34 expression ratewas 0.0% and the endothelial cell marker CD31 expression rate was 0.7%, in line with the characteristics of umbilicalcord mesenchymal stem cell surface markers. Calcium nodules by alizarin red staining and lipid droplets by oil red Ostaining were observed in the induced cells. These experimental findings indicated that umbilical cord mesenchymalstem cells from tree shrews capable of osteogenic and adipogenic differentiation were successfully isolated and cultured.

BACKGROUND:Tree shrew is a representative between insectivore and primates, has a high degree of evolution, is more inexpensive primates, has high use of medical biology, and has been attached by scholars. OBJECTIVE:To detect whether the commonly used secondary antibodies have immune response with tree shrew serum. METHODS:Western blot assay and enzyme linked immunosorbent assay were utilized to detect whether the tree shrew serum had cross-reacts with anti-rabbit, anti-goat, anti-human, anti-mouse, anti-rat, and anti-monkey secondary antibodies. RESULTS AND CONCLUSION:Western blot assay results indicated that tree shrew serums did not react with anti-rabbit, anti-goat, anti-human, anti-mouse, and anti-rat secondary antibodies and had cross reaction with anti-monkey secondary antibody. Enzyme linked immunosorbent assay results also indicated that tree shrew serums were cross-reactive with anti-monkey secondary antibody, but did not have cross-reactivity with the other secondary antibodies. Above data confirmed that the usual y soled secondary antibody cannot be used to immunoassay with tree shrews IgG. Only anti-monkey secondary antibody has cross-react with tree shrew serum. It is necessary to prepare anti-tree shrew IgG monoclonal and polyclonal antibodies. When no antibody is readily available at present, anti-monkey secondary antibody can be used to substitute detection, and can be widely applied in the study of tree shrew models of disease.

BACKGROUND:Systemic lupus erythematosus is an autoimmune disease characterized as an emergence of a variety of autoantibodies in serum and multi-system and multi-organ lesions. Currently, there is a lack of effective treatment options, and umbilical cord mesenchymal stem cel s are a promising therapy for systemic lupus erythematosus based on cel biological roles. OBJECTIVE:To observe the therapeutic efficacy of human umbilical cord mesenchymal stem cel transplantation in the treatment of systemic lupus erythematosus in mice. METHODS:Human umbilical cord mesenchymal stem cel s were isolated and cultured fol owed by labeling with DiR fluorescence. Experimental mice were divided into normal control group (C57BL mice), model control group (C57BL/lpr mice), low-, medium-and high-dose umbilical cord mesenchymal stem cel therapy groups (C57BL/lpr mice), with 10 mice in each group. Mice in the low-, medium-and high-dose groups were respectively injected 0.5×106, 1×106, 2×106 human umbilical cord mesenchymal stem cel s, once a week, for 3 consecutive weeks. At the end of treatment, blood samples were col ected to measure antinuclear antibody, anti-histone antibody, anti-double stranded DNA antibody changes;OPG and Foxp3 gene expression changes were detected by quantitative PCR method. RESULTS AND CONCLUSION:After treatment, the levels of anti-nuclear antibodies, anti-histone antibodies and anti-double stranded DNA antibodies in the peripheral blood of mice were al declined in the low-, medium-and high-dose groups, while the number of peripheral blood CD4+CD25+T cel s was significantly elevated. OPG and Foxp3 gene expression was also increased dramatical y in the low-, medium-and high-dose groups, which was similar to that in the normal control group and significantly different from that in the model control group (P<0.01). Experimental findings demonstrate that after transplantation of human umbilical cord mesenchymal stem cel s, al relevant indicators in C57BL/lpr mice recovered to the normal levels, and the high-dose treatment group had the most obvious effect.

Objective:To analyze the chicken egg-white extracts were co-cultured with cells whether elevated stem cells protein,whether the cells transformation into stem cell.Methods:Four kinds of cells,making a common culture,a 50% chicken egg-white extract co-cultured for 3 days,cells were collected and frozen at -80 degrees,sending the company to do stem cell protein microarray.Results:C57-BMSC has three proteins occurred statistically significant change , TS-UC-MSC has one proteins occurred a statistically significant change ,293T has one protein occurred a statistically significant change ,and 293T-GFP has one protein occurred a statistically significant change.Conclusion:50% chicken egg-white extract co-cultured cells,the cells occurred the phenomenon of transformation into stem cells.

BACKGROUND:If an extract can prolong the S phase and reduce the percentage of apoptosis after co-culture with cels, it is proved that the extract is able to promote cel proliferation. OBJECTIVE: To prove the effects of chicken egg-white extracts with different components on the proliferation, cel cycle and apoptosis of 293T cels. METHODS: An ultrafiltration unit was used to separate chicken egg-white extracts into different components that were > 10 ku, < 10 ku, > 3 ku and < 3 ku to co-culture with cels for 3 days. Then, cel proliferation, cel cycle and cel apoptosis were detected. RESULTS AND CONCLUSION:Chicken egg-white extract components of < 10 ku and < 3 ku could promote cel proliferation, increase the percentage of S-phase cels and reduce the percentage of apoptosis. In conclusion, chicken egg-white extract components that are < 10 ku and < 3 ku can promote cel proliferation, as wel as increase the percentage of S-phase cels and reduce apoptosis percentage.

BACKGROUND:There are less studies addressing whether bone marrow mesenchymal stem cells from systemic lupus erythematosus patients are different from healthy people.
OBJECTIVE:To compare the multi-differentiation capacity of bone marrow mesenchymal stem cells isolated from systemic lupus erythematosus model mice and normal control mice.
METHODS:Bone marrow mesenchymal stem cells of systemic lupus erythematosus model mice and C57BL mice were isolated and cultured fol owed by osteogenic and adipogenic differentiations, respectively. Differentiation abilities of two kinds of mouse bone marrow mesenchymal stem cells were observed.
RESULTS AND CONCLUSION:Passaged bone marrow mesenchymal stem cells from C57BL mice were long spindle-shaped and evenly distributed, while bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice showed slow growth and were relatively smal er than those from C57BL mice. After osteogenic induction, the amount of calcium salt and calcium nodules were significantly less in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice than from normal control mice. PCR detection showed that expressions of Runx2, alkaline phosphatase and osteocalcin were also significantly decreased in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice. After adipogenic induction, the number of lipid droplets in the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice was significantly less than the control group, and PCR detection also showed significantly decreased expression of adipogenic genes, including PPARγ2 and lipoprotein lipase. These findings suggest that the bone marrow mesenchymal stem cells from systemic lupus erythematosus model mice exhibit lower osteogenic and adipogenic capacities than those from normal C57BL mice, and also have the impaired multi-differentiation ability.

BACKGROUND:Reprogramming somatic cells to generate pluripotent stem cells has a wide application in biomedical research. OBJECTIVE:To analyze the effect of different molecular weight proteins in chicken egg-white extract to elevate expression of pluripotent genes Oct-3/4 and Nanog in 293T cells. METHODS:The extracts of chicken egg-white were separated into more than 3 ku and less than 3 ku ingredients to be used for co-culture with 293T cells. There were four groups, 1×105 293T cells per wel , total 500μL. In the control group, 500μL culture medium was added;in the other three groups, 500μL chicken egg-white extract, more than 3 ku and less than 3 ku ingredients were respectively added. Quantitative PCR was used to determine the relative expression levels of pluripotent genes Nanog and Oct-3/4 in 293T cells. RESULTS AND CONCLUSION:By using co-culture method, more than 3 ku ingredients have a role to increase the expression of pluripotent genes Oct-3/4 and Nanog, but less than 3 ku ingredients cannot elevate the expression of pluripotent genes. This indicates that the ingredient of chicken egg-white extract to elevate the expression of pluripotent genes is more than 3 ku proteins.

BACKGROUND:Umbilical cord as childbirth waste has wide variety of sources and can be easily obtained, without any ethical and legal restrictions. Therefore, human umbilical cord mesenchymal stem cells break al the restrictions originated from other sources of mesenchymal stem cells. OBJECTIVE:To review the application of human umbilical cord mesenchymal stem cells in cartilage diseases, neuroglioma, ischemic brain injury, lung disease, liver disease and models of myocardial infarction. METHODS:The PubMed and Wanfang databases were searched by the first author using the keywords of“human umbilical cord mesenchymal stem cells, disease models, celltherapy”in English and Chinese, respectively. Seventy-three articles were searched and final y, 35 articles were included in result analysis. RESULTS AND CONCLUSION:Human umbilical cord mesenchymal stem cells have multilineage differentiation capacity similar to bone marrow mesenchymal stem cells. Compared with bone marrow mesenchymal stem cells, human umbilical cord mesenchymal stem cells have lower immunogenicity. Human umbilical cord mesenchymal stem cells show certain curative effects on cartilage disease, neuroglioma, ischemic brain injury, lung disease, liver disease and myocardial infarction, indicating that human umbilical cord mesenchymal stem cells can be used for celltransplantation to treat various diseases.