Background The incidence of dry eye is gradually increased,and researches showed that inflammation participated in the pathogenesis and development of dry eye.The current therapy for dry eye can only relieve symptom but not achieve final cure.Stem cell therapy has been used in the treatment of limbal stem cell deficiency.However,whether it is feasible for the stem cell treating dry eye is still unclear.Objective This study attempted to investigate a new approach to treat dry eye syndrom by using human umbilical cord mesenchymal stem cells (HUCMSCs).Methods The use and care of experimental animals complied with the Tsinghua University School of Medicine Laboratory Animal Care Details.HUCMSCs were cultured and cell suspension was prepared with the cell density of 5×105/ml.Twenty 24-week-old male NOD/Ltj mice were randomized into 4 groups.0.1 ml PBSHUCMSCs suspension was injected via tail vein or lacrimal respectively in the caudal vein injection group and lacrimal injection group,and 10 μ1 PBS-HUCMSCs suspension was topically administed in the eye drops group.The NOD/Ltj mice without any treatment served as the model group.Five male ICR mice were used as the normal control group.Tear secretion was quantitatively detected with phenol red cotton thread in 1,2,3 weeks after injection,and corneal epithelial defect was scored by fluorescein staining.The serum levels of interleukin (IL)-6,IL-17a,tumor necrosis factor-α (TNF-αt) and interferon-γ (IFN-γ) were assayed by ELISA.The relative expression levels of p65,Stat3,Stat5 and extracellular signal-regulated kinases (Erk)-1 in lacrimal gland were detected by Western blot.Results The tear secretion amount was significantly different among the model group,caudal vein injection group,lacrimal injection group and eye drops group in various time points (1 week:F =3.700,P =0.040;2 weeks:F =5.150,P =0.008;3 weeks:F=10.130,P＜0.001).The tear secretion amount was increased in the caudal vein injection group and lacrimal injection group compared with the model group in different time points (all at P＜0.05),and no significant difference was seen in tear secretion amount between eye drops group and model group among various time points (all at P＞0.05).The fluorescein staining score was 3.00±0.63,9.40±1.62,5.20±1.17,4.20±1.17 and 7.20±0.98 in the ICR mouse control group,model group,caudal vein injection group,lacrimal injection group and eye drops group 1 week after injection respectively,and the scores were significantly lower in the caudal vein injection group,lacrimal injection group and eye drops group than those in the model group (P =0.001,0.000,0.033).The serum levels of IL-6,IL-17a and TNF-α in the caudal vein injection group were evidently lower than those in the model group (t =4.70,3.46,11.0,all at P＜0.01),but no significant difference was displayed in the serum IFN-γ level among the five groups (F=1.740,P=0.170).The expressions of STAT5 were significantly decreased in the mice treated with tail vein injection and lacrimal injection compared with mice without treatment (both at P＜0.05).Conclusions Administration of HUCMSCs via intravenous and lacrimal injection can alleviate the inflammatory response during progression of dry eye syndrome by down-regulating the serum level and expression of inflammation-related factors in NOD/Ltj mice.The topical administration of HUCMSCs eye drops can attenuate the symptom of dry eyes by lubricating the cornea and suppling nutrition.

【Objective】 To explore the difference of demographics and influencing factors of motivations between whole blood donors and plasmapheresis donors, so as to provide scientific reference for effective recruitment strategy. 【Methods】 A total of 200 whole blood donors from Guangyuan Blood Center and 200 plasmapheresis donors from Jiange Plasmapheresis Station were selected in August 2021 for on-site questionnaire survey using the method of cross-sectional survey. Statistical analysis was performed by chi-square test, univariate and multivariate logistic regression. 【Results】 There were significant differences in gender, age, occupation, education level and annual family income between whole blood donors and plasmapheresis donors (P<0.05). Males accounted for a large proportion of whole blood donors(124/196, 63.3%), whereas females accounted for a large proportion of plasmapheresis donors(117/198, 59.1%). There was little difference in the number of whole blood donors in different age groups, while the age of plasmapheresis donors was concentrated in 40~59 years old (167/198, 84.3%). In terms of occupation, civil servants (including public institutions) accounted the highest proportion in whole blood donors (41/196, 20.9%), and farmers accounted the highest proportion (152/198, 76.8%) in plasmapheresis donors. The number of whole blood donors increased with the education level, and donors with college/university and above degree accounted the largest proportion (80/196, 40.8%). Plasmapheresis donors with junior middle school education and college/university and above accounted the largest and smallest proportion (49.5% vs 4.5%). The annual family income of whole blood donors ranged from 30 000 to 80 000 yuan accounted the largest proportion (109/196, 55.6%), and the annual family income of plasmapheresis donors less than 30 000 yuan accounted the largest proportion (132/198, 66.7%). 【Conclusion】 There were significant statistical differences in gender, age, education level, occupation and annual family income between whole blood and plasmapheresis donors. Therefore, targeted recruitment strategies should be formulated.

【Objective】 To analyze the characteristics and mobility of the overlapping population of voluntary blood donation and plasmapheresis donation, so as to provide a scientific basis for the formulation of recruitment and retention strategies for blood donation and plasmapheresis donation, and to further propose a scientific reference for the decision-making of blood banks and plasmapheresis station management in China. 【Methods】 The basic information of blood donors and plasmapheresis donors in two counties in Guangyuan, Sichuan Province, which carried out whole blood collection and plasmapheresis collection from the establishment of the station to July 31, 2021 was statistically compared and analzed using the chi-square test and Post hoc testing test. 【Results】 As of July 31, 2021, a total of 50 658 people participated in blood donation and 63 375 people participated in plasmapheresis donation in Jiange County and Cangxi County, with a total overlap of 6 189 people. In the two regions, 16 458 (35.2%) people aged 40 to 50, and 35 558 people (56.1%) were over 50 years old. Among the overlapping population, 2 496 (40.3%) were 40 to 50 years old, accounted for the largest proportion, and 3 146 (50.8%) were males. Significant differences were noticed in age (P<0.001) and gender (P<0.001). There was a shift in dontion in 5 183, including 2 072 people from plasma to blood and 3 111 people from blood to plasma, among which 2 671 (51.5%) were men and 3 632 (70.1%) were over 50 years old, with significant differences in gender (P<0.05) and age (P<0.001). 【Conclusion】 There were a small number of donors donating both blood and plasma in Jiange and Cangxi, and men aged 40 to 50 were the majority, and people over 50 years old were more likely to shift the donation goals. The vast majority of donors have a single and fixed donation goal (blood or plasma), and are not easy to change.

【Objective】 To analyze the dynamic relationship between the setting up of plasmapheresis station and the volume of voluntary blood donation collected using panel vector autoregressive model, so as to provide scientific reference for the management policies of blood stations and plasmapheresis stations in China. 【Methods】 The data collected from blood stations in seven administrative regions of Guangyuan, Sichuan Province from 2011 to 2021, as well as plasma collection data from two plasmapheresis stations in the region within two years since their operation, were collected. A panel vector autoregressive model was constructed. Impulse response analysis and variance decomposition analysis were used to analyze the impact and time lag effects of simulated plasmapheresis station settings on the collection volume of voluntary blood donation. Covariance analysis was used to explore whether the establishment of plasmapheresis station had an impact on the volume of voluntary blood donation collected after excluding the impact of initial value differences. 【Results】 The pulse response results showed that after the plasmapheresis station was set up, there was a negative impact effect on the voluntary blood donation collection volume at the first stage, and its impact began to rise after the second stage, reached the highest value in the third stage, and then began to decline. After the seventh stage, it tended to be stable. However, within the 10 stage range, the confidence interval for the response strength of voluntary blood donation collection volume always included 0, indicating that the response of blood collection volume to the plasmapheresis station setting in the region was not statistically significant. The results of variance decomposition showed that the contribution of collection volume of voluntary blood donation to their own impact reached 94.3%. In terms of the contribution of plasmapheresis station factors, the number of plasma donors has a relatively greater impact on the volume of voluntary blood donation collected(2.2%). Covariance analysis showed that after removing the initial confounding factors, whether to establish a plasmapheresis station had no significant impact on blood donation volume in the two groups of regions (P>0.05). 【Conclusion】 The establishment of a new plasmapheresis station will have a certain impact on blood collection volume of blood stations in the region in a short term, but in the long term, it may not directly affect the voluntary blood donation collection in the region.