BACKGROUND:Neural stem cells, as a hot topic in neuroscience research, have a wide application prospect in the treatment of neurological damage, but how to obtain a large number of terminally differentiated and purified nerve cells with homogeneous features is a difficult problem in this field. The use of intracellular fluorescence reporter system to track the process of neural stem cell differentiation and obtain a single kind of terminally differentiated and purified nerve cells provides a viable option. OBJECTIVE: To explore the value of GFAP promoter-driven fluorescence reporter system in tracing the neural differentiation of neural stem cells (NSCs). METHODS: Cerebral cortex of mouse embryos were primarily dissociated and sent for digesting and pipetting mechanically before suspension culture, followed by immunofluorescence staining of Nestin to identify their biological characteristics. Lentivirus carrying pLV/Final-neo-GFAP(promoter)-dTomato vector was employed to infect above-mentioned NSCs, and Geneticin (G418) was used to obtain purified NSCs at 14 days. Subsequently the purified cells were induced to differentiate into astrocyte-like cells; meanwhile red fluorescence changes in cells were observed by microscopy. The red fluorescent cells were then subjected to perform immunofluorescence staining at 13 days after induction. RESULTS AND CONCLUSION:The expression of Nestin in the isolated primary cells was strongly positive. Purified NSCs were obtained by lentivirus infection and subsequent G418 resistance selection at 14 days. After induced into astrocyte-like cells, the red fluorescence was observed in the cells under the microscope and furthermore, GFAP staining was also positive. Mouse NSCs carrying neo-GFAP(promoter)-dTomato were successfully obtained. The cells could express dTomato under the control of GFAP promoter, which provides a powerful tool for research on NSC differentiation mechanism, neural transplantation and tissue engineering product development.

BACKGROUND:As the pharmacological effect of eugenol constantly being discovered, its application in medical and food industry becomes wider. However, its toxicity studies have not established a complete database, especialy in the improvement of safety assessment of developmental toxicity and teratogenicity. OBJECTIVE:To establish a model of embryonic stem cel test to evaluate the embryotoxicity of eugenol. METHODS:Mouse fibroblasts (3T3) and mouse embryonic stem cels (E14TG2a) were culturedin vitro, and MTT test was performed to detect the cytotoxicity of 3T3 cels and E14TG2a cels with positive control 5-fluorouracil, negative control penicilin G and tested compound eugenol. The concentration of the tested compounds that inhibiting 50% viability of embryonic stem cels (IC50 E14TG2a) and 3T3 fibroblasts (IC50 3T3) was calculated. The hanging-suspension-adherent culture systems were used to induce embryonic stem cels into cardiomyocytes, and the concentration of tested compounds that caused 50% inhibition of differentiation of E14TG2a cels into cardiomyocytes (ID50 E14TG2a) was calculated. The embryotoxic potential of eugenol was classified by prediction model of the embryonic stem cel test. RESULTS AND CONCLUSION:The proliferations of E14TG2a and 3T3 cels were inhibited by eugenol, of which the IC50 3T3 and IC50 E14TG2a values were (3.613±0.192) and (1.799±0.131) mg/L. The differentiation of E14TG2a was also inhibited by eugenol, of which the ID50 E14TG2a was (3.501±0.158) mg/L. Eugenol was evaluated as a chemical compound with strong embryotoxicity by the model of embryonic stem cel test.

Objective To establish a model of embryonic stem cell test(EST)and utilize this model to evaluate the embryotoxici-ty of hydroquinone.Methods Mouse 3T3 fibroblasts and mouse embryonic stem(ES)cells(ES-E14TG2a)were cultured in vitro, and methyl thiazolyl tetrazolium(MTT)test was performed to detect the cytotoxicity of 3T3 cells and ES-E14TG2a cells induced by the positive control(5-fluorouracil),negative control(penicillin G)and tested compound(hydroquinone).The concentrations of the test compounds that inhibited 50% viability of ES-E14TG2a cells(IC50 ES)and 3T3 fibroblasts (IC50 3T3)were calculated.The hanging-suspension-adherent culture systems were used to induce embryonic stem cells into cardiomyocytes,and the concentrations of test compounds that caused 50% inhibition of differentiation of ES-E14TG2a cells into cardiomyocytes (ID50 ES)was calculated. The embryotoxic potential of hydroquinone was classified by prediction model of the embryonic stem cell test.Results The prolif-eration of ES-E14TG2a and 3T3 cells were inhibited by hydroquinone,of which the IC50 3T3 and IC50 ES values were (5.97±0.48) and (2.57±0.10)μg/mL respectively.The differentiation of ES-E14TG2a cells were also inhibited by hydroquinone,of which the ID50 ES was (3.77±0.31)μg/mL.Hydroquinone was evaluated as a strong embryotoxicity chemical by prediction model of EST. Conclusion Hydroquinone exhibits a strong embryotoxicity.

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Objective To investigate the clinical features,diagnosis and treatment experience of idiopathic calcinosis of the scrotum(ICS).Methods We report 5 cases with a 4-month to 20-year history of ICS.The related literatures were reviewed.Results The multiple scrotum masses in these patients were increased slowly in size and number.The levels of blood calcium and phosphorus were normal.Histopathologically,nodules were composed of basophilic calcified material and located in the dermis.There was no epithelial lining around the calcified nodules.Conclusion ICS is a rare localized benign disease.The diagnosis of the tumor relies largely on the histopathology.Surgical excision is the best choice for treatment.

Objective To study the shadowing effect when using UWB bio-radar to detect multiple static human targets to solve the problem in multi-target detection.Methods With simulated breathing apparatus as detection targets,the UWB bioradar multi static targets respiration detection experiment was designed,and the influences of distance and angle between targets and its respiratory frequency and amplitude on the shadowing effect were studied.Result The shadowing effect was mainly affected by the relative position of the multiple targets,while the respiratory frequency and amplitude of the target had less influence on it.Conclusion When multi static human targets are detected the shadowing effect does exist,and the effect mainly derives from the block of electromagnetic wave by the front target,while the change of respiratory parameters of the front target has little influence on the effect.

Sepsis is an organ dysfunction that endangers a patient's life caused by an imbalanced infection response, and is a clinically critical illness. Despite a deep understanding of the pathogenesis of sepsis, there has been no significant improvement in sepsis mortality during clinical treatment at home and abroad. In recent years, the role of autophagy in the pathogenesis of sepsis has become a new research point in the field of medical research. Autophagy may protect the body by removing pathogenic microorganisms, neutralizing microbial toxins, and regulating cytokine release in sepsis. Studies have shown that autophagy plays a role in heart and lung organ dysfunction and inflammatory immune response in sepsis. Studies have also shown that hydrogen sulphide (H 2S) can activate autophagy through multiple signaling pathways, such as adenylate-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR), phosphoinositide 3 kinase/Akt/mTOR (PI3K/Akt/mTOR), liver kinase B1/STE20 related adapter protein/mouse protein 25 (LKB1/STRAD/MO25) and microRNA-30c (miR-30c), etc. signaling pathways. This article reviewed the effects of H 2S on autophagy-related genes Beclin-1 and microtubule-associated protein light 3 chain (LC3) on intestinal function of sepsis in order to explore the H 2S-mediated autophagy gene expression in pus. The protective role of autophagy gene for intestinal dysfunction provides a new strategy for the treatment of sepsis in the future.

Sepsis is one of the main causes of death in critically ill patients. The intestinal tract is not only the organ easily involved in sepsis, but also the initial organ in the progression of sepsis, so the improvement of intestinal barrier function is the key of the treatment of sepsis. In recent years, it has been found that autophagy is involved in the pathological process of sepsis, maintaining mitochondrial function by clearing damaged organelles, inhibiting inflammation, oxidative stress and apoptosis, regulating immunity, maintaining intestinal homeostasis, and improving the condition and prognosis of sepsis. It is an effective target for the treatment of sepsis. As a new type of medical gas signal molecule, hydrogen sulfide (H 2S) can regulate autophagy by regulating multiple signal pathways, which has become a new target in the treatment of sepsis. This article reviews the signal pathway regulation mechanism of H 2S regulating autophagy in septic intestinal dysfunction.