Plant expression cassette for TaDREB from wheat was constructed into plasmid pBIR1.Aloe stems were used as explants for the transformation mediated by Agrobaterium.Infected tissues were selected using G418 to generate transformants.In total,58 resistant plantlets to the antibiotics were obtained from the infected explants.The designed primers according to the selective gene npt II and the target gene TaDREB were used to analyze all of the G418 resistant plantlets.PCR results demonstrated that TaDREB were successful transferred into aloe genomic with the transformation efficiency of 0.5%.The transgenic aloe plants were treated under 4℃ for two weeks and then at-20℃ for 30min.The treatment showed that the leaves of negative plants appeared severe evidence of freeze injury with brown,withered and translucent,while the positive plants appeared good growing condition.The activities of enzymes such as peroxidase(POD)and superoxide dismutase(SOD)of transgenic plants which were stressed for 14 days under low temperature were analyzed.The results indicated that the trend of SOD and POD activities in transgenic plants was down-up-up-up,and that in non-transgenic plants was down-up-down-down.The average value of relative electrical conductivity in the positive plants was 0.456 which was lower than 0.685 in the negative plants.It is supposed that transformation of the kind of gene could improve the resistant ability of aloe to low temperature.

Objective To evaluate effects of fine particulate matter PM2.5 in ambient air on the proliferation,cell cycle and apoptosis of a human keratinocyte cell line HaCaT.Methods PM2.5 in hazefog episodes during the heating season was collected in Beijing from 2015 to 2016,and processed into PM2.5 suspensions.HaCaT cells were divided into several groups to be treated with culture medium alone (control group),PM2.5 suspensions at different concentrations of 100-400 mg/L (experiment groups,50-800 mg/L for observation of cellular morphology and analysis of cell proliferation) for 24 hours,or cell culture medium without cells or PM2.5 suspensions (blank group).Cellular morphological changes were observed under an inverted microscope.Cell counting kit-8 (CCK-8) assay was performed to determine cell survival rate,flow cytometry to determine the cell cycle distribution and detect cell apoptosis,and Western blot analysis to determine the protein expression of cyclin A2 and cyclin-dependent kinase1 (CDK1).Results Along with the increase of PM2.5 concentration,HaCaT cells lost their normal shape gradually,and the number of viable cells gradually decreased.Compared with the control group (100％ ± 4.95％),the 50-mg/L PM2.5 group showed no changes in cell survival rates (P ＞ 0.05),while the 100-,200-,400-and 800-mg/L PM2.5 group showed significantly lower survival rates (91.77％ ± 2.04％,80.01％ ± 1.57％,57.80％ ± 1.56％,21.98％ ± 0.86％,respectively,all P ＜ 0.05).Flow cytometry revealed that the 100-,200-and 400-mg/L PM2.5 groups showed gradually increased proportion of cells at S phase,but gradually decreased proportion of cells at G2/M phase compared with the control group (all P ＜ 0.05).As Western blot analysis showed,the protein expression of cyclin A2 and CDK1 significantly decreased in the 100-,200-and 400-mg/L PM2.5 groups compared with the control group,which was lowest in the 200-mg/L PM2.5 group(all P ＜ 0.05).In addition,the 100-,200-and 400-mg/L PM2.5 groups showed significantly higher total apoptosis rates (9.98％ ± 0.21％,12.56％ ± 0.74％,16.74％ ± 1.48％,respectively) compared with the control group (6.24％ ± 0.17％,all P ＜ 0.05).Conclusion PM2.5 can inhibit cell proliferation and promote apoptosis of HaCaT cells,likely by downregulating the expression of cyclin A2 and CDK1 and arresting HaCaT cells at S phase.

Objective To analyze the composition of bacteria and fungi on the facial skin of healthy women aged 20-25 years in Beijing by using high-throughput sequencing technology,and to compare the composition and diversity of microbes among 4 kinds of subjective skin types.Methods Totally,31 female undergraduates were enrolled from Beijing Technology and Business University,and classified into 4 groups,including dry skin group (n =6),neutral skin group (n =8),mixed skin group (n =9) and oily skin group (n =8),according to their subjective feeling of facial skin greasiness and dryness.On 24th December 2017,the facial skin water content,transepidermal water loss (TEWL),sebum content and pH value were determined for these undergraduates,and these physiological parameters of the skin were compared among the 4 kinds of subjective skin types.Skin samples were collected with swabs from the cheeks of these subjects.After DNA extraction and PCR amplification,the bacterial 16S rRNA regions V1-V2 and fungal internal transcribed spacer regions 1 and 2 (ITS-1-ITS-2) were sequenced separately,and sequences were grouped by OUT cluster analysis at 97％ sequence similarity followed by classification and annotation of species.One-way analysis of variance was used for intergroup comparison,and least significant difference (LSD)-t test for multiple comparison.Results The sebum content and bacterial diversity of the facial skin both significantly differed among the 4 kinds of subjective skin types.The skin sebum content in the dry skin group,neutral skin group,mixed skin group and oily skin was 5.50 ±4.60 μg/cm2,7.69±5.26 μg/cm2,10.56 ± 5.42 μg/cm2,22.81 ± 8.53 μg/cm2 respectively (F =11.685,P ＜0.001),and the Shannon index of bacterial diversity in the above 4 groups was 3.49 ± 0.70,2.97 ± 1.43,2.49 ± 0.63 and 1.59 ± 0.59 respectively (F =5.634,P =0.004).Propionibacterium,Staphylococcus and Streptococcus were the main bacterial florae on the face.The relative abundance of Propionibacterium was significantly higher in the oily skin group (68.24％ ± 14.78％) than in the dry skin group (18.83％ ±14.49％,P ＜ 0.001),neutral skin group (32.18％ ± 36.29％,P ＜ 0.001) and mixed skin group (35.22％ ±22.58％,P ＜ 0.001).In addition,the relative abundance of Staphylococcus was highest in the mixed skin group,and the relative abundance of Streptococcus was highest in the neutral skin group.There was no significant difference in the fungal diversity (Shannon index) or richness (Chao index) among the 4 groups (both P ＞ 0.05).The fungi on the facial skin of these subjects mainly consisted of Ascomycota and Basidiomycota,and no significant difference in their relative abundance was observed among the 4 groups (both P ＞ 0.05).Moreover,there was no significant difference in the composition of fungal genera at relative abundance ＞ 1％ among the 4 groups (all P ＞ 0.05).Conclusion The physiological parameters and bacterial diversity of the cheek skin differed among young women of different subjective skin types,while there was no difference in the fungal diversity or richness,suggesting that the colonization of skin bacteria is associated with subjective skin types.

Objective:To analyze the difference in skin surface lipids (SSL) between facial skin lesions of neonates with acne and normal facial skin of healthy infants.Methods:SSL samples were collected from facial skin lesions of 36 neonates with acne (acne group) and normal facial skin of 36 healthy infants (control group) at the Department of Dermatology, Children′s Hospital, Capital Institute of Pediatrics from June 2018 to August 2018. A lipid map was constructed by ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-QTOF-MS), and specific information about lipid components was obtained by multivariate data analysis. Independent-sample t test was performed with SPSS19.0 software for comparisons between 2 groups. Results:Compared with the control group, the acne group showed significantly increased relative content of glycerolipids and prenol lipids on the facial skin surface (both P < 0.001), but significantly decreased relative content of fatty acids, glycerophospholipids, sphingolipids, sterol lipids, saccharolipids and polyketides ( P < 0.01 or 0.05) .Further analysis showed that the average relative content of total lipids, diglycerides, wax esters and squalene was significantly higher in the acne group than in the control group ( P < 0.001 or 0.05), but the average relative content of linoleic acid was significantly lower in the acne group than in the control group ( P < 0.001) . Conclusion:Compared with the facial skin of healthy infants, the facial skin lesions of neonates with acne showed significantly increased total lipid content and different lipid components.