Xenotransplantation is one of the effective ways to overcome the shortage of donor organs. However, the molecular incompatibility between xenotransplantation donors and recipients can cause rejection, which greatly limits the clinical application of xenotransplantation. In recent years, researchers have deeply explored the mechanism of xenotransplantation rejection through xenotransplantation models of pig-to-monkey and pig-to-brain death recipients, and found that the innate immune system plays an important role in rejection. Macrophages, as phagocytes in the innate immune system, not only damage xenografts through phagocytosis but also interact with other immune cells to influence the immune microenvironment of xenotransplantation. However, due to the heterogeneity of macrophages, their phenotypes and functions in xenotransplantation rejection remain unclear. Therefore, it is necessary to further explore the role of macrophages in xenotransplantation rejection. This article reviews the latest research progress of macrophages in xenotransplantation rejection, aiming to explore the mechanisms of macrophages in xenotransplantation rejection and provide references for future research.

CD47 is a transmembrane protein widely expressed on cell surface, which is considered as a key molecule for immune escape. With an increasing number of related studies, the role of CD47 and its ligands in immunomodulatory effects has been gradually understood. Recent studies have investigated the role of CD47 in ischemia-reperfusion injury of allogenetic kidney transplantation, rejection and xenotransplantation. Nevertheless, the specific role and the key mechanism remain elusive. In this article, the structure and function of CD47, common CD47 ligands, the relationship between CD47 and kidney transplantation, and the application of CD47 in kidney transplantation were reviewed, the latest research progress of CD47 in kidney transplantation was summarized, and the limitations of current research and subsequent research direction were analyzed, aiming to provide reference for subsequent application of CD47 in allogeneic and kidney xenotransplantation.

Objective To explore the clinical efficacy and safety of modified PPH combined with partial internal anal sphincterotomy in the treatment of circular mixed hemorrhoids.Methods Patients with annular mixed hemorrhoids were divided into two groups by a completely randomized controlled method.54 patients in the experimental group were treated with modified PPH combined with partial internal anal sphincterotomy,while 51 patients in the control group were treated with conventional PPH.The postoperative indicators,perioperative and long-term complication rates of the two groups were compared,and the clinical efficacy and safety were observed.Results The operation time in the experimental group was(48.35±4.37)minutes,which was higher than that in the control group(36.42 ±6.21)minutes(P＜0.05).The incidence of postoperative anastomotic stenosis in the experimental group was 1.9％,lower than 15.6％ in the control group(P＜0.05).Anal pain,urinary retention,first defecation time,long-term anal distention,the experimental group was significantly better than the control group,the difference was statistically significant(P＜0.05);The hospitalization time in the experimental group(4.8±0.62)days was not significantly different from that in the control group(5.1±0.54)days(P＞0.05).The amount of intraoperative bleeding and anastomotic bleeding in the experimental group[(17.28±2.22)ml,3.7％]were not significantly different from those in the control group[(16.75± 2.13)ml,3.9％](P＞0.05).Conclusion Compared with conventional PPH,the modified PPH combined with partial internal anal sphincterotomy slightly increases the operation time,but does not increase the risk of anastomotic bleeding,the incidence of rectal fistula,the amount of surgical bleeding,and the length of hospital stay.It can significantly improve postoperative anal pain,urinary retention,long-term distention symptoms,shorten the time of first defecation,ease the difficulty of defecation,and significantly reduce postoperative anastomotic stenosis,The long-term efficacy and safety are good.

Objective:To investigate the effect of a single-trial transcranial direct current stimulation(tDCS) of the dorsolateral prefrontal cortex (DLPFC) on fairness-related decision-making behavior.Methods:From September 2018 to February 2019, a total of 60 healthy participants between the ages of 18 and 45 were enrolled.Then, the participants were randomly divided into 3 groups with 20 in each group to receive left anode stimulation/right cathode stimulation (left anode /right cathode group), left cathode/right anode stimulation (left cathode /right anode group) or bilateral control electrodes (sham stimulation group) on the bilateral dorsolateral prefrontal cortices (DLPFC), respectively.After tDCS, the participants immediately completed the ultimatum game (UG) task as responders and a fairness questionnaire in turn.SPSS 22.0 statistical software was used to analyze the data with repeated measurement ANOVA and nonparametric test.Results:In the UG task, there was no significant difference in the acceptance rate among the three groups of participants as responders (all P>0.05). When analyzing the acceptance rate facing different proposers (" computer" and " human" ) under different fairness levels in the three stimulus types through the paired samples Wilcoxon test, it was found that the acceptance rate of the sham stimulation group to the extremely unfair proposals proposed by the human opponent was lower than that proposed by the computer(0.28 (0, 0.67), 0.44 (0.33, 0.89), Z=-2.14, P=0.032), while there was no difference in acceptance rates (both P>0.05) in the face of fair or unfair proposals proposed by computer and human opponents.The acceptance rate of the left cathode /right anode group to the unfair(0.90 (0.50, 1.00), 1.00 (0.70, 1.00), Z=-1.90, P=0.046)or extremely unfair(0.44 (0, 1.00), 0.89 (0.50, 1.00), Z=-2.73, P=0.006) proposals proposed by human opponents was significantly lower than the proposals proposed by computer opponent, and there was no differences in acceptance rate when facing fair proposals proposed by computer and human opponents ( P> 0.05). There were no significant differences in acceptance rates in the left anode /right cathode group when faced with fair, unfair, and extremely unfair schemes proposed by computer and human opponents (all P>0.05). For fairness questionnaire scores, a repeated measurements ANOVA showed that the interaction effect between group and proposer types was not significant ( F(2, 54)=2.037, P=0.140), and the group main effect was not significant ( F(1, 54)=0.165, P=0.848), but the proposer type main effect was significant ( F(1, 54)=6.363, P=0.015), indicating that the fairness questionnaire score in the face of the human opponents was lower than when facing the computer opponents( P<0.05). Conclusion:Although a single-trial tDCS on bilateral DLPFC has no significant effect on the overall acceptance rate of fairness-related decision-making, it affects the decision-making of unfair distribution scheme proposed by human or computer.

Objective:To investigate the level of serum vascular endothelial growth factor (VEGF) and its correlation with clinical symptoms in patients with first-episode drug-naive schizophrenia patients of different genders.Methods:From January 2016 to October 2019, a total of 81 first-episode drug-naive schizophrenia patients(patient group, 41 male, 40 female) and 64 healthy controls (control group, 40 male, 24 female) were included in this study.The serum level of VEGF was detected with flow cytometric bear array (CBA). Positive and negative symptom scale (PANSS) was used to evaluate the relevant clinical symptoms of patients.SPSS 22.0 software was used for statistical analysis.Independent sample t-test and nonparametric test were used for comparison between groups.The relationship between VEGF and clinical variables was analyzed by Pearson correlation analysis and Spearman correlation analysis. Results:The level of serum VEGF in the patient group was significantly lower than that in the control group(148.08(75.89, 208.61)pg/mL, 179.94(99.14, 318.41)pg/mL, Z=-2.20, P=0.028). The total PANSS score((82.71±17.30), (73.45±16.36), t=2.473, P=0.016)and cognitive score((7.88±3.36), (6.23±2.81), t=2.402, P=0.019) in male patients were higher than those in female patients.There was a negative correlation between VEGF level and PANSS negative symptom score in the patient group( r=-0.228, P=0.041), as well as significant negtive correlation between VEGF level and cognitive score in male patients( r=-0.425, P=0.007). Conclusion:The level of serum VEGF is reduced in first-episode patients with schizophrenia, which influences their negative symptom. Moreover, the decline in serum VEGF level is implicated in cognitive impairments in male patients with first-episode schizophrenia.

Transuranics radionuclides are ubiquitous in the environment. Long term intake will cause internal radiation hazards, and it is also an important source of radioactive contamination to the environment in the future. In this paper, the source and migration behavior of transuranic radionuclides are reviewed, the existing problems in China are summarized, and the suggestions for future work are put forward.

Objective:To overcome the disadvantages of bismuth removal by bismuth sulfide precipitation method recommended by existing analytical standards and improve the quality of analytical result.Methods:Based on 201×7 anion exchange resin, the experimental process of bismuth removal was designed, and verified by using spiked samples and IAEA test samples.Results:Bismuth was removed by anion exchange resin. In the removal experiments of strontium, yttrium and bismuth, the chemical recovery rate of strontium and yttrium could reach (98.6 ± 0.8)% and (98.5 ± 0.7)%, respectively, with no Bi 2S 3 precipitation found. The relative standard deviation between analytical result and theoretical values was -2.97% to 5.94%, better than 3.96%-17.8% by the standard bismuth removal method. Through validation using IAEA test samples, the relative standard deviation between the reported value and the target value for 90Sr was between 3.40%-7.09%, and all the results were acceptable. Conclusions:Bismuth could be quantitatively removed using anion exchange resin without adsorption of strontium and yttrium. In addition, the bismuth removal solution system of anion exchange resin was the same as the elution system in 90Sr analysis, and the purpose of rapid bismuth removal could be achieved without conversion system. Compared with the current standard analytical method, it was feasible and better to quantitatively remove bismuth based on anion exchange resin, which could meet the needs of routine analysis of 90Sr.

Prenatal care services are an important part of my country's public health services, and play an important role in enhancing the pregnancy and childbirth experience of urban migrant women and improving their pregnancy and childbirth outcomes. The accessibility of prenatal care services is an important indicator for evaluating the equalization of basic public services. This paper outlines the concept and measurement dimensions of the accessibility of prenatal care services. This paper also analyzes the factors affecting the accessibility of prenatal care services for urban migrant women in my country from the perspectives of service providers, demanders, and both parties, and proposes strategies to improve the accessibility of prenatal care services for urban migrant women.

Objective:To explore the preparation and preliminary research on the characteristics of modified nano-bioglass hydrogel.Methods:(1) The nano-bioglass suspension was prepared by adding 67 mL nano-silica suspension into 400 mL saturated calcium hydroxide solution, and its suspension stability was observed. (2) The hydrogel with final mass fraction of 10% gelatin and 1% sodium alginate was prepared and set as control group. On the basis of the hydrogel in control group, the nano-bioglass suspension prepared in experiment (1) was added to prepare the hydrogel with the final mass fraction of 0.5% bioglass, 10% gelatin, and 1% sodium alginate, and the hydrogel was set as the experimental group. The gelling time at 4 and 25 ℃and the dissolution time at 37 ℃ of hydrogel in 2 groups were recorded, and the gelation at 4 and 25 ℃and dissolution condition at 37 ℃of the hydrogel in 2 groups were observed. The hydrogel in 2 groups were collected and cross-linked with 25 g/L calcium chloride solution after cold bath at 4 ℃, and the compression modulus was measured by Young′s modulus tester. In addition, the hydrogel in 2 groups were collected and cross-linked as before, and freeze-drying hydrogel was made at -20 ℃. The relative volumes were measured and the porosity of hydrogel in 2 groups was calculated. The number of sample in the experiment was 3. (3) Fibroblasts (Fbs) were isolated and cultured from 12 C57BL/6J mice of 24 hours old and the morphology was observed by inverted microscope, and the third passage of Fbs were cultured for the following experiment. Fbs were collected to make single cell suspension with the cell concentration of 1×10 5/mL. The single cell suspension was divided into experimental group and control group according the random number table (the same grouping method below), which were added with hydrogel in experimental group and control group prepared in experiment (2), respectively. At culture hour 12, 24, and 48, cells of 3 wells in each group were collected to detect the survival rate by cell counting kit 8 method. (4) The third passage Fbs were collected to prepare the single cell suspension with the cell concentration of (3.0~4.5)×10 7/mL, which was divided into experimental group and control group, with 1 tube in each group. The single cell suspension in 2 groups were added with green fluorescent probe DIO for staining and then added with 9 mL hydrogel in experimental group and control group prepared in experiment (2), respectively. The mixed solution of Fbs and hydrogel in 2 groups was cross-linked as before to make cell-loaded hydrogel. On culture day 3, the survival of cells in the hydrogel was observed by laser confocal microscope. The cell-loaded hydrogel was prepared as before and without added with green fluorescent probe DIO. On culture day 7, the adhesion and extension of cells in the hydrogel were observed by scanning electron microscope. (5) Twelve 6-week-old female BALB/c-nu nude mice were collected and divided into experimental group and control group, with 6 mice in each group. A round full-thickness skin defect wound with diameter of 1 cm was made on the back of each mouse. Immediately after injury, one cell-loaded hydrogel block in the experimental group and the control group prepared in experiment (4) was placed in the wound of each mouse in the experimental group and the control group, respectively. On post injury day (PID) 7 and 14, 3 nude mice in each group were sacrificed to collect the wound and wound margin tissue, which was stained with hematoxylin-eosin to observe the wound healing. Data were statistically analyzed with independent sample t test. Results:(1) The nano-bioglass particles could be uniformly dispersed in water and had good suspension stability. (2) The hydrogels of the 2 groups were molten at 37 ℃, and no precipitation of particle was observed. The dissolving time of the hydrogel in the experimental group and the control group at 37 ℃ was 5 and 10 min, respectively. The gelation time of the hydrogel in the experimental group and the control group at 25 ℃ was 30 and 180 min, respectively, and the gelation time of the 2 groups at 4 ℃ was 5 and 10 min, respectively. The compression modulus of hydrogel in the experimental group was (53±6) kPa, which was significantly higher than (23±6) kPa in the control group ( t=6.364, P<0.01). The porosity of the hydrogel in the experimental group was (86.1±2.1)%, which was similar to (88.2±4.4)% in the control group ( t=1.210, P>0.05). (3) The cells were in long fusiform, and the proportion of nuclei was high, which was accorded with the morphological characteristics of Fbs. At culture hour 12, 24, and 48, the survival rate of cells in the experimental group was (84±4)%, (89±4)%, and (130±10)%, which was similar to (89±5)%, (90±4)%, and (130±11)% in the control group, respectively ( t=1. 534, 0.611, 0.148, P>0.05). (4) On culture day 3, the cells in the two groups had complete morphology in the hydrogel, no nuclear lysis or disappearance were observed, the cytoplasm remained intact, and the fluorescence intensity of the cells in the experimental group was significantly stronger than that in the control group. On culture day 7, the cells in the experimental group and the control group adhered and stretched in the hydrogel, and the number of cells in the experimental group adhered to the hydrogel was significantly more than that in the control group. On PID 7, the wound area of the nude mice in the control group and the experimental group were reduced, the reduction area of mice in the experimental group was more obvious, and a large amount of inflammatory cells were seen in and around the wound in the 2 groups. On PID 14, the wound area of the nude mice in the control group was larger than that of the experimental group, and the number of inflammatory cells in and around the wound was significantly more than that in the experimental group. Conclusions:Nano-bioglass hydrogel possesses good physical, chemical, and biological properties, cell loading potential, and the ability to promote wound healing, which means it has a good potential in clinical application.

Objective: To explore the correlation between serum high density lipoprotein (HDL) levels and cognitive function in patients with bipolar disorder. Methods: A total of 99 patients with bipolar disorder were enrolled from the inpatient of Suzhou Guangji Hospital.Serum HDL levels were measured by enzymatic colourimetry.Cognitive function was assessed by the repeatable battery for the assessment of neuropsychological status (RBANS). The relationship between serum high density lipoprotein and cognitive function was analyzed by correlation analysis and stepwise multiple regression analysis. Results: Serum HDL levels ((1.39±0.55)mmol/L)were positively correlated with the RBANS total score (68.92±12.48)(r=0.238, P=0.034) and language score(80.59±15.97) (r=0.239, P=0.033) in patients with bipolar disorder.Stepwise multiple regression analysis showed that serum HDL level was the influencing factor of total score of RBANS(β=4.791, t=2.151, P=0.035)and speech function(β=7.363, t=2.247, P=0.027). Conclusion Serum HDL levels can influence cognitive function, especially speech function in patients with bipolar disorder.