ABSTRACT
Abstract@#Allergic diseases can occur in all systems of the body, covering the whole life cycle, from children to adults and to old age, can be lifelong onset and even fatal in severe cases. Children account for the largest proportion of the victims of allergic disease, Children s allergies start from scratch, ranging from mild to severe, from less to more, from single to multiple systems and systemic performance, so the prevention and treatment of allergic diseases in children is of great importance, which can not only prevent high risk allergic conditions from developing into allergic diseases, but also further block the process of allergy. At present, there is no consensus on the management system of allergic children in kindergartens and primary schools. The "Consensus on Allergy Management and Prevention in Kindergartens and Primary Schools", which includes the organizational structure, system construction and management of allergic children, provides evidence informed recommendations for the long term comprehensive management of allergic children in kindergartens and primary schools, and provides a basis for the establishment of the prevention system for allergic children.
ABSTRACT
BACKGROUND: P75 neurotrophin receptor (P75NTR) has a bidirectional role in promoting and inhibiting bone formation in bone tissue. Overexpression of P75NTR can inhibit the osteogenic mineralization of bone marrow mesenchymal stem cells. P75NTR can inhibit the degradation of fibrin and the formation of new blood vessels around the fracture, leading to fracture nonunion. Its inhibition of bone tissue repair is related to its mediating apoptosis channels. OBJECTIVE: To study the effect of silencing P75NTR on the growth activity and alkaline phosphatase activity of bone marrow mesenchymal stem cells, and to study the ectopic osteogenesis ability implanted in demineralized bone matrix to construct tissue engineering bone complex. METHODS: Lentivirus-mediated silencing P75NTR was transfected into bone marrow mesenchymal stem cells. The expression of fluorescent protein and P75NTR protein was detected by fluorescence inverted phase contrast microscope and western blot assay. Two or three days after transfection, CCK-8 assay was used to detect cell activity. After osteogenic induction solution induced differentiation culture for 7 and 14 days, alkaline phosphatase activity was detected by enzyme labeling method. Lentivirus-mediated silencing P75NTR transfected bone marrow mesenchymal stem cells were cultured with compound demineralized bone matrix. Optical inverted phase contrast microscope and scanning electron microscope were used to observe the adhesion of demineralized bone matrix and bone marrow mesenchymal stem cells. After further osteogenic differentiation for 7 days, tissue engineered bone complex was subcutaneously implanted in the rat back for 4 weeks. The osteogenesis was observed by hematoxylin-eosin staining and alkaline phosphatase staining. RESULTS AND CONCLUSION: (1) Lentiviral-mediated silencing P75NTR transfection rate was approximately 70%. The expression of P75NTR target protein was significantly lower than that of untransfected group and negative virus control group (P < 0.05). (2) Compared with untransfected group and negative virus control group, the cell activity of silencing P75NTR transfected group increased significantly at 5 and 6 days (P < 0.05). Compared with the untransfected group and the negative virus control group, the alkaline phosphatase activity of silencing P75NTR transfected group increased significantly at 7 and 14 days after osteogenic induction (P < 0.05). (3) Silencing P75NTR transfected bone marrow mesenchymal stem cells and demineralized bone matrix formed a good adhesion; the tissue engineered bone complex significantly enhanced the ability of ectopic bone formation. (4) The results showed that bone marrow mesenchymal stem cells transfected with silencing P75NTR mediated by lentivirus could be implanted in decalcified bone matrix to form a good tissue engineered bone complex, which has a certain heterotopic osteogenesis effect and provides important theoretical basis for bone tissue engineering in the treatment of bone defects.
ABSTRACT
BACKGROUND: Nitric oxide (NO) has been shown to be important in sperm function, and the concentration of NO appears to determine these effects. Studies have demonstrated both positive and negative effects of NO on sperm function, but have not been able to provide a clear link between NO concentration and the extent of exposure to NO. To study the relationship between nitric oxide and sperm capacitationin vitro, and to provide a theoretical basis for the use of NO-related preparations in improving sperm motility for in vitro fertilization, we investigated the effects of NO concentration and time duration at these concentrations on in vitro sperm capacitation in both normal and abnormal sperm groups. We manipulated NO concentrations and the time duration of these concentrations using sodium nitroprusside (an NO donor) and NG-monomethyl-L-argenine (an NO synthase inhibitor). RESULTS: Compared to the normal sperm group, the abnormal sperm group had a longer basal time to reach the appropriate concentration of NO (p < 0.001), and the duration of time at this concentration was longer for the abnormal sperm group (p < 0.001). Both the basal time and the duration of time were significantly correlated with sperm viability and percentage of progressive sperm (p < 0.001). The experimental group had a significantly higher percentage of progressive sperm than the control group (p < 0.001). CONCLUSIONS: We hypothesize that there is a certain regularity to both NO concentration and its duration of time in regards to sperm capacitation, and that an adequate duration of time at the appropriate NO concentration is beneficial to sperm motility.