Objective To study the changes and mechanism of skin stem cells in microgravity.Methods The skin stem cells of SD rats were used to establish a suspension culture system and compare the proliferation of skin stem cells with 1G gravity.Results The simulated microgravity significantly affected the velocity of skin stem cell sphere proliferation in suspension culture,which was about 12%higher than the 1G gravity group.Transcriptome sequencing showed that 1673 genes were up-regulated and 1409 genes were downregulated;Calcium signaling;cytokine-cytokine receptor interaction and PPAR pathway were different in the two environments.Conclusion Simulation of microgravity can affect the proliferation behavior of skin stem cells in suspension culture by regulating the expression of key signaling pathways,which provides an experimental basis for further research in spatial microgravity environ ment.

Objective:To construct the nursing quality evaluation index system of hemodialysis vascular access, so as to provide reference for the evaluation and improvement of vascular access quality.Methods:Using the Donabedian three-dimensional structural quality evaluation tool, combined with literature search, semi-structured interviews, and Delphi method, expert consultation forms were sent via email, WeChat, and other means. Two rounds of consultation were conducted with 15 experts in clinical nursing, nursing management and medical work in the field of hemodialysis vascular access from 9 provinces and municipalities in China to determine the evaluation index system. The enthusiasm of experts was expressed by the effective response rate of the questionnaire, the degree of coordination of expert opinions was expressed by the coordination coefficient and coefficient of variation, and the degree of expert authority was expressed by the expert authority coefficient.Results:The effective response rates of the two rounds of expert inquiry questionnaires were both 100.00% (15/15). The judgment coefficient of expert consultation was 0.900, familiarity coefficient was 0.827, the authority coefficient was 0.864, and the coordination coefficients of the first, second, and third level indicators were 0.280, 0.267, and 0.206, respectively ( P<0.05). The final quality evaluation index system for hemodialysis vascular access nursing includes 3 primary indicators, 11 secondary indicators, and 39 tertiary indicators. Conclusions:The nursing quality evaluation index system for hemodialysis vascular access is reasonably set, the construction process is rigorous, and it has high scientificity and reliability. It can provide objective and quantifiable reference basis for the nursing quality evaluation of hemodialysis vascular access.

Objective To investigate the effects of microgravity environment on hibernating myoblasts.Methods Hibernating myoblasts were cultured under real and simulated microgravity conditions for 10 days.RNA-seq analysis and immunofluorescence are used to analysis the impact of microgravity environment on cell growth and gene expression of myoblasts.Results Under the microgravity conditions,genes associated with proliferation were upregulated.Under simulated microgravity,there were more and higher proportion of Ki67 positive cells compared to normal gravity conditions.Conclusion The microgravity environment promotes the proliferation of hibernating myoblasts.

Poly(dimethyl siloxane)(PDMS)is suitable for the fabrication of space cell culture chips.It is necessary to perform highly stable hydrophilic modification to promote cell adhesion on PDMS surface.We modified PDMS surface by oxygen plasma treatment combining with physical adsorption in this article.PDMS,which was treated with oxygen plasma and sequentially coated with Poly-L-lysine or collagen(PLL-ox-PDMS,COL-ox-PDMS)with various solution concentration and kept in different environmental conditions,were characterized by contact angle and surface energy measurements,and atomic force microscopy(AFM).Cell growth conditions on bare PDMS and modified PDMS were compared,and the numbers of live cells cultured for 1-3 days were evaluated.Experimental results indicate that higher solution concentration and low storage temperature benefit the hydrophilicity stability.The contact angles of PLL-ox-PDMS stored in 4℃and COL-ox-PDMS were close to 60°and 65°on day 25 and 14,respectively.Both modified PDMS surfaces are suitable for cell adhesion and proliferation,and no cell layer falls offin 10 days.The modification method is especially suitable for applications such as medium and long term space cell culture.

Objective To explore the strategies of using psychological crisis intervention in public emergencies.Methods In the early stage,psychological crisis intervention concepts and behavioral responses were formed through literature research and qualitative research methods.Use three rounds of Delphi for expert advice.Three indexes including positive coefficient,authority and coordination were used to test the reliability of expert consultation.Results Overall,it passed 239 out of 269 entries.The first round passed item 210,modified item 18,no consensus item 41;In the second round,8 new entries were added,and 22 entries were deleted through 24 entries.In the third round,there were 5 entries and 16 entries were deleted.The authority coefficient was 0.859,indicating that the experts were very familiar with the items.The coordination coefficient of three rounds of consultations were 0.464,0.696,and 0.407 (P＜0.001)respectively,showing that the coordination degree of experts was excellent,the credibility of feedback was high,and results were highly reliable.Conclusions The strategies of field psychological crisis intervention for public emergencies developed in this study received the consensus by domestic psychological crisis intervention experts,it is will provide a basis for systematic,comprehensive and effective guidance for this work.

Objective: To evaluate the efficacy of consolidation chemotherapy combined with allogeneic natural killer (NK) cell infusion in the treatment of low or intermediate-risk (LIR) acute myeloid leukemia (AML) . Methods: A cohort of 23 LIR AML patients at hematologic complete remission (CR) received NK cell transfusion combined with consolidation chemotherapy after 3 consolidation courses from January 2014 to June 2019 were reviewed. Control group cases were concurrent patients from Department of Hematology, and their gender, age, diagnosis, risk stratification of prognosis, CR and the number of courses of consolidate chemotherapy before NK cell transfusion were matched with LIR AML patients. Results: A total of 45 times of NK cells were injected into 23 LIR AML patients during 4 to 7 courses of chemotherapy. The median NK cell infusion quantity was 7.5 (6.6-8.6) ×10⁹/L, and the median survival rate of NK cells was 95.4% (93.9%-96.9%) . Among them, the median CD3^-CD56⁺ cell number was 5.0 (1.4-6.4) ×10⁹/L, accounting for 76.8% (30.8%-82.9%) ; The number of CD3⁺ CD56⁺ cells was 0.55 (0.24-1.74) ×10⁹/L, accounting for 8.8% (4.9%-20.9%) . Before NK cell infusion, the number of patients with positive MRD in the treatment and control groups were 9/23 (39.1%) and 19/46 (41.3%) (χ²=0.030, P=0.862) respectively. After NK infusion, There was no significant difference in terms of MRD that went from negative to positive between the treatment and the control groups (14.3% vs 22.2%, χ²=0.037, P=0.847) . In the treatment group, 66.7% (6/9) of the MRD were converted from positive to negative, which was significantly higher than that in the control group (10.5%, 2/19) (χ²=6.811, P=0.009) . Morphological recurrence occurred in 1 case of MRD negative in the treatment group and 2 cases of MRD positive in the control group. By the end of follow-up, the median follow-up was 35 (10-59) months, the number of patients with morphological recurrence in the treatment group was 30.4% (7/23) , which was significantly lower than that in the control group (50.2%, 24/46) (χ²=2.929, P=0.087) , although there was no statistically significant difference between the two groups. There was no significant difference on MRD-negative between the treatment and the control groups (43.5% vs 43.5%, χ²=1.045, P=0.307) . The 3-year leukemia-free survival was better in the treatment group [ (65.1±11.1) %] than that in the control group [ (50.0±7.4) %] (P=0.047) . The 3-year overall survival in the treatment and control groups were (78.1±10.2) % and (65.8±8.0) % (P=0.212) , respectively. Conclusion The consolidation of chemotherapy combined with allogeneic NK cell infusion contributed to the further remission of patients with LMR AML and the reduction of long-term recurrence.

Objective To assess the clinical efffects off Ipratropium bromide combined with atomization inhalation of budesonide via a ventilator with a Y-shaped connector on acute exacerbation off chronic obstructive pulmonary disease (AECOPD).Methods A total off 62 AECOPD patients treated at our hospital from June 2013 to September 2014 were randomly divided into the experimental group (n=31,treated with ipratropium bromide combined with atomization inhalation of budesonide) and the control group (n =31,treated with the same amount of saline).Results The airway pressure of mechanical ventilation,the time of mechanical ventilation and the time of staying in the intensive care unit all showed significant differences between the experimental and control groups [(25.4±5.2) cmH2O vs.(38.1±3.4) cmH2O,(6.5±1.3) d vs.(6.8±1.4) d,(8.9±2.1) d vs.(9.5±1.5) d,t=10.934,0.960,1.108,respectively,P＜0.05 for all].The rate of tracheotomy was lower in the experimental group than in the control group (17/31 or 54.8％ vs.20/31 or 64.5％,x2 =0.603,P＜0.05).Conclusions Ipratropium bromide combined with budesonide inhalation under mechanical ventilation via a Y-shaped connector has ffavorable clinical effects on AECOPD.

Objective To investigate the prenatal diagnosis and phenotypic assessment strategies for fetal supernumerary marker chromosomes and derivative chromosomes. Methods Five cases of fetal supernumerary marker chromosomes and one case of fetal derivative chromosomes were diagnosed in the First Affiliated Hospital of Sun Yat-Sen University from March 12, 2010 to November 9, 2012 by conventional chromosome banding, fluorescence in situ hybridization (FISH) and spectral karyotyping (SKY). These cases were retrospectively reviewed. Combined with the results of ultrasonography, abnormal phenotypes and pregnancy outcomes were evaluated in these cases. Results All of the five supernumerary marker chromosomes were de novo, in which two were mosaic and the remaining three cases were non-mosaic. Of these five cases, two were type 47, XX+mar and ultrasound indicated abnormal phenotypes. FISH and SKY confirmed that they were derived from chromosome 4 and 22, respectively. The other three cases were marker chromosome with Turner syndrome karyotype (abnormal phenotypes were not found by ultrasound), in which two cases were derived from chromosome Y (by FISH) and one case was identified as ring chromosome X (by FISH and SKY). One de novo derivative chromosome was verified as a product of reciprocal translocation between chromosome 2 and 6 (by FISH and SKY). Induced abortion was performed in all cases between 25 and 32 gestational weeks. Conclusions By combining conventional chromosome banding, FISH and SKY, the origin and content of supernumerary marker chromosomes and derivative chromosomes can be identified. On this basis, clinical phenotype evaluation and genetic counseling may be offered with the ultrasonographic result.

Objective To investigate the value of Cylex ImmuKnow immune cell function assay in the diagnosis of infection after liver transplantation. Methods The objects of this prospective study were 48 patients undergoing orthotopic liver transplantation (OLT) in Liver Transplantation Center, the Third Affiliated Hospital of Sun Yat-sen University from July 2010 to December 2012. The informed consents of all patients were obtained and the ethical committee approval was received. According to whether the patients suffered clinical infection or not after OLT, they were divided into two groups:infection group (n=14) and non-infection group (n=34). Another 20 healthy people were enrolled as the control group. There were 11 males and 3 females in the infection group with a mean age of (47±10) years old. There were 29 males and 5 females in the non-infection group with a mean age of (45±9) years old. There were 10 males and 10 females in the control group with a mean age of (42±10) years old. Peripheral venous blood 2 ml was collected from the patients on the 7th day after OLT or from the healthy people when enrolled in control group. The adenosine triphosphate (ATP) level in cluster of differentiation (CD) 4+ lymphocyte was detected using Cylex ImmuKnow kit and the testing data were compared using t test. Results The ATP level in CD4+ cells was (178±58), (345±62), (467±84) mg/L in infection group, non-infection group and control group respectively. The ATP level in infection group was significantly lower than that in non-infection group (t =-4.6, P<0.05). The sensitivity of the Cylex ImmuKnow immune cell function assay in the diagnosis of infection after OLT was 0.79, the specificity was 0.85, the positive predictive value was 0.69, and the negative predictive value was 0.91. Conclusions Cylex ImmuKnow immune cell function assay can simply and quickly detect the immune cell function. It plays a role in monitoring and diagnosing the infection after OLT.

Objective To investigate the clinical value of ultrasound markers in screening fetal trisomy 21.Methods From Jan.2001 to Dec.2011,a retrospective study about sonographic information of 138 fetuses diagnosed as trisomy 21 was taken in the First Affiliated Hospital of Sun Yat-sen University.All fetuses were divided into 3 groups:isolated ultrasound markers,non-isolated ultrasound markers,and isolated structural malformations or other abnormalities.The relationship between trisomy 21 and ultrasound markers as well as structural anomalies or other abnormalities was analyzed.Results Sonographic anomalies were detected in 132 fetuses(95.7％,132/138),including ultrasound markers and structural malformations or other abnormalities.One hundred and twenty cases(87.0％,120/138)had ultrasound markers,38(31.7％,38/120)had one marker and 82(68.3％,82/120)had more than one marker (P ＜ 0.01).Fifty-one fetuses(37.0％,51/138)had isolated ultrasound markers and non-isolated markers were found in 69 fetuses(50.0％,69/138).Only 12 fetuses(8.7％,12/138)had isolated structural malformations or other abnormalities.In 20 fetuses on whom the first-trimester ultrasound screening were performed,all had ultrasound markers,95％(19/20)had thickened nuchal translucency and 55％ (11/20)had nasal bone hypoplasia.The most common ultrasound markers on the second-trimester screening were nasal bone hypoplasia,which accounted for 41.9％(52/124)cases,followed by thickened nuchal fold (25.0％,31/124),short fenurs and humerus(24.2％,30/124),echogenic intracardiac focus(16.1％,20/124),mild ventriculomegaly(15.3％,19/124),hyperechoic bowel(12.9％,16/124),mild renal pyelectasis(12.1％,15/124).Furthermore,thc common structural malformations or other abnormalities were as follows:cardiac defects(33.1％,41/124),digestive system(26.6％,33/124).Condusions Ultrasound markers are valuable for screening fetal trisomy 21.The fetuses of trisomy 21 usually had more than one ultrasound markers or associated with other abnormalities.Combinations of ultrasound markers with the results of serum screening and maternal age are necessary for evaluation.