BACKGROUND: Embryonic stem cells (ESCs), the seed cells of all mature cells in vivo, are useful tools for nerve transplantation and developmental gene function research. Notch1 signaling pathway is the key pathway to control the ordered neural development and differentiation of many kinds of neural cells, however, there is no report on the dynamic expression of Notch1 signal during the ESC differentiation to date. OBJECTIVE: To investigate the expression of Notch1 protein, transmembrane signal transduction molecule, during directional differentiation of embryonic stem cells into neural cells. DESIGN, TIME AND SETTING: Cell research was carried out between October 2003 and October 2004 at Zhongshan Ophthalmic Center, SUN Yat-sen University, Guangzhou, Guangdong Province, China. MATERIALS: BALB/C mouse embryonic stem cell line Ⅵ (passage 11)was obtained from experimental animal center of SUN Yat-sen University, provided by professor Huang Bing. ESC culture medium was high-glucose DMEM medium with 20% bovine serum and 106 IU/L mouse leukemia inhibitory factor. Induced differentiation medium was high-glucose DMEM medium with 20% fetal bovine.serum and 5×107 mol/L retinoid acid(RA). METHODS: Passage 11 ESCs were resuscitated and incubated by ESC culture medium in incubator at 37℃ with 5% CO2. Passage 11 ESCs were subcultured after 2 or 3 days and RA was added into medium to induce differentiation. Three time points for observation were established: induced for 1, 5 and 9 days. MAIN OUTCOME MEASURES: Morphological changes were observed under inverted phase contrast microscope, MAP-2 antigen expressed in differentiated cells was detected by immunofluorescence method. Immunocytochemistry, Western Blot, flow cytometry assay were used to investigate the Notch1 protein expression. RESULTS: ESCs presented clone-like growth. After induced by RA for 9 days, single neural network was achieved around most of the cell clusters. With the prolongation of induction, MAP-2 positive neural cells increased gradually. Almost all ESC clones expressed Notch1 protein strongly or positively, but Notehl protein expression decreased gradually after induced differentiation (P < 0.01). CONCLUSION: Notch1 signal shuts off progressively during induction of ESCs into neural cells, which suggests Notch1 may play an important role in the differentiation of ESCs into neural cells.

AIM: To investigate the feasibility and effect of directly differentiation of embryonic stem cells(ESC) into neural cells induced by retinoid acid(RA) without embryonic body(EB) culture period in vitro.METHODS: ESC were digested and divided into 4 groups: group A and B were undergone EB culturing.After that,cells in group A were induced by RA,cells in group B were differentiated spontaneously,cells in group C were committedly induced by RA directly without EB culturing,and cells in group D were differentiated spontaneously without EB period.Morphologic changes were observed under inverted microscope and scanning electron microscope.MAP-2 and GFAP were detected by immunocytochemistry and flow cytometry after differentiated for 9 days.RESULTS: In groups A or C,neuron-like cells increased gradually,forming neural network.At the 9th day,a large part of cells in these groups were MAP-2 positive cells,and the positive rate was higher than that in groups B or D(P0.05).CONCLUSION: ESC was directly induced into neural cells by RA without EB culture period in vitro.This modified method has the same effect as the traditional RA 4-/4+ assay and can replace the traditional method.

OBJECTIVE: Utilize high-resolution chromosome analysis and microarray detection to determine the genetic etiology of infertility of a 32-year old female patient. METHODS: The peripheral blood of the patient was cultured for high-resolution chromosome G and C banding karyotype analysis, and then 750K SNP-Array chip detection was performed. RESULTS: Karyotype analysis results showed that the patient's karyotype was 45,XX,-13 [7]/46,XX,r(13) (p13q34) [185]/46,XX,dic r(13;13)(p13q34;p13q34) [14]/ 47,XX,+der(13;13;13;13) (p13q34;p13q34;p13q34; p13q34), dic r(13;13) [1]/ 46,XX [3]. The microarray results showed that the patient had a 3.3 Mb deletion in the 13q34 segment of chromosome 13, which may be related to infertility. CONCLUSION Infertility of the patient reported in this article may be related to the deletion of chromosome segment (13q34-qter).
Adult ; Chimera ; Chromosome Banding ; Chromosome Deletion ; Chromosome Disorders/genetics* ; Dacarbazine ; Female ; Humans ; Infertility/genetics* ; Ring Chromosomes

OBJECTIVE：To p rovide reference for related pharmacy work for developing evidence-based pharmacy information support to respond for novel coronavirus pneumonia （COVID-19） epidemic. METHODS ：The PubMed，CNKI and Wanfang database were consulted to obtain treatment progress of COVID-19，prohibited for use with lopinavir/ritonavir and adverse drug reactionas until February 12，2020；so were package insert and UpToDate at the same time. Those information were summarized and evaluated. RESULTS & CONCLUSIONS ：Totally 14 literatures introduced chemical drugs for COVID- 19，involving 7 categories， 20 kinds of chemical drugs as antiviral drugs （interferon α/interferon α-2 β ， lopinavir/litonavir， etc.）， immunomodulatory agents （such as glucocorticoid ，gamma globulin ），antimalarial drugs （such as chloroquine phosphate ）. The existing evidence of drug treatment mainly comes from in vitro cell test or currently progressing RCT ，with low-level evidence and recommendation intensity （Oxford evidence level is level 5，recommendation intensity is level D ）. For lopinavir/ritonavir that recommended in the diagnosis and treatment recommendations for COVID- 19 published by the National Health Commission ，it is a CYP3A inhibitor ，which resulted in increased plasma concentrations of some medications such as antiarrhythmic drugs ，antitumor targeted drugs and antibacterial drugs ，and should not be used in combination with drugs such as afzosin ，ivabradine，amiodarone， etc. Its common adverse reactions mainly involved igestive system （diarrhea，taste disorders ，vomiting，etc.），respiratory system （upper respiratory tract infection ），endocrine and metabolic system （hypercholesterolemia，etc.），skin and its appendents （skin rash），which should be monitored clinically.