Deer antlers are the unique mammalian organs that can be periodically regenerated,i.e.,they hold interest for researchers on stem cells and regenerative medicine,and have the potential to become an excellent biomedical research model.Deer antler regeneration may use stem cells.Antler growth appears to involve specific stimulation of the necessary stem cells present in the locality,and involves similar mechanisms to those used in limb development,unlike the regenerative process in the newt.Development regulation of antler and growth mechanism of antler stem cells have significance in limb regenerated medicine and stem cell research.Many scientists have carried out thorough research on the deer antlers development,thus,have drawn many concepts.This article reviews the field of deer antlers development such as antler regeneration and stem cells,and introduces research technique of antler development and relevant theories.

Objective To establish Ad-LIF-OSM transgenic feeder cells for the expansion of CD34+ hematopoietic stem/progenitor cell and tentatively study its effect in expansion and differentiation of cord blood hematopoietic stem cell(HSC) in vitro.Methods In the foundation of pAdTrack-CMV-LIF-polyA+promoterΔ,the OSM gene was inserted to the vector plasmid.Then we structure the transfer plasmid pAdTrack-CMV-LIF-polyA+promoterΔ-OSM.The transfer vector and backbone vector were further cotransfected for homologous recombination. The result pAdEasy-1-pAdTrack-CMV-LIF-polyA + promoterΔ-OSM homologous recombination plasmid were transfected into the human embryonic kidney 293 (QBI-293A) cells,leading to formation of the recombinant adenviruses Ad-LIF-OSM which co-expressing LIF and OSM.Infect the feeder layer cells with groups of Adenovirus,detection the expressing of LIF and OSM in WI-38 cells by RT-PCR and ELISA.Compares the stem cells differentiation and proliferation of the different experimental groups in vitro by transwell and cell counting.Results The sequencing results show that the OSM genes were anastomotic in Ad-LIF-OSM.LIF and OSM gene could be detected in feeder layer cells which infected by Ad-LIF-OSM.Exogenetic LIF and OSM have special effect in culturing HSC in vitro.Conclusion The adenoviral vector co-expressing LIF and OSM (Ad-LIF-OSM) were successfully constructed.Ad-LIF-OSM transgenic feeder cells can effectively proliferate umbilical cord blood CD34+ HSPC in vitro and delay it differentiate.

Objective To evaluate the effectiveness and associated factors of prevention of motherto-child human immunodeficiency virus (HIV) transmission in Hubei Province,and to provide a reference for prevention of mother-to-child transmission of HIV.Methods In this prospective cohort study,HIV-positive pregnant women who were in some counties and cities of Hubei Province from January 2004 to December 2016 were enrolled.Prevention of mother-to-child transmission of HIV was conducted for these HIV-positive pregnant women and their infants,and their clinical data were collected.Descriptive analysis and x2 test were used to analyze the general characteristics of HIV-positive pregnant women and their infants.Logistic regression analysis was adopted to explore the associated factors of mother-to-child HIV transmission.Results In total,536 HIV-positive pregnant women (628 pregnancies) were found,among which,334 pregnant women and 345 infants were enrolled in this study.Twenty-four infants were HIV-positive,which was 6.96％ in all infants (95％CI:4.27％-9.64％).The rates of mother-to-child HIV transmission without prevention,formula feeding only,infant medication plus formula feeding,mother and infant medication plus formula feeding were 35.71％ (95％CI:21.61％-51.93％),8.82％ (95％CI:2.08％-15.57％),7.41％ (95％CI:0.92％-24.22％),and0.48％ (95％CI:0.01％-2.64％),respectively.No antiretroviral medications during delivery (OR =14.484,95 ％CI:1.740-120.577,P=0.013),breastfeeding (OR=6.542,95％CI:2.416-17.713,P=0.000),and CD4-T lymphocyte count＜200 cells/μL during delivery (OR=3.060,95％CI:1.076-8.703,P=0.036) were independent risk factors of mother-to-child HIV transmission.Conclusions The rate of mother-to-child HIV transmission without prevention is high in Hubei Province,which can be significantly reduced by comprehensive interventions (mother and infant medication plus formula feeding).Thus,we should diagnose HIV-positive pregnant women as early as possible,and should give pregnant woman antiretroviral therapy plus infant medication and formula feeding to further reduce the rate of mother-to-child HIV transmission.