OBJECTIVE To investigate the targeting effect of folic acid-modified crebanine nanoparticles （FA-Cre@PEG- PLGA NPs， hereinafter referred to as “NPs”） combined with ultrasound irradiation on M109 cells in vitro and in vivo after administration， and explore the anti-tumor mechanism. METHODS CCK-8 assay was used to detect the inhibitory effect of NPs combined with ultrasound irradiation on the proliferation of M109 cells， and the best ultrasound time was selected. Using human lung cancer A549 cells as a control， the targeting of NPs combined with ultrasound irradiation to M109 cells was evaluated by free folic acid blocking assay and cell uptake assay. The effects of NPs combined with ultrasound irradiation on the migration， invasion， apoptosis， cell cycle and reactive oxygen species （ROS） levels of M109 cells were detected by cell scratch test， Transwell chamber test and flow cytometry at 1 h after 958401536@qq.com administration； the changes of mitochondrial membrane potential （MMP） were observed by fluorescence inverted microscope. A mouse subcutaneous tumor model of M109 cells was constructed， and the in vivo tumor targeting of NPs combined with ultrasound irradiation was investigated by small animal in vivo imaging technology. RESULTS NPs combined with ultrasound irradiation could significantly inhibit the proliferation of M109 cells， and the optimal ultrasound time was 1 h after administration. The free folic acid could antagonize the inhibitory effect of NPs on the proliferation of M109 cells， and combined with ultrasound irradiation could partially reverse this antagonism. Compared with A549 cells， the uptake rate of NPs in M109 cells was significantly higher （P＜0.01）， and ultrasound irradiation could promote cellular uptake. NPs combined with ultrasound irradiation could inhibit the migration and invasion of M109 cells and block the cell cycle in the G0/G1 and G2/M phases. Compared with control group， the apoptosis rate of M109 cells and ROS level were increased significantly （P＜0.01）， while the MMP decreased significantly （P＜0.01） in the different concentration （100， 200， 300 μg/mL） groups of M109 cells. Compared with the mice in non-ultrasound group， the fluorescence intensity and tumor-targeting index of the tumor site in the 0 h ultrasound group were significantly enhanced （P＜0.05 or P＜0.01）. CONCLUSIONS NPs combined with ultrasound irradiation have a strong targeting effect on M109 cells in vitro and in vivo， the anti-tumor mechanism includes inhibiting cell migration and invasion， blocking cell cycle， and inducing apoptosis.

In the past decade, high-throughput sequencing technologies have generated a massive amount of genomic mutation data. The interpretation of mutation data from tumor samples has revealed mutational features highly associated with carcinogenic factors, which are referred to as mutational signatures. These mutational signatures enable the assessment of the contribution rates of various carcinogenic factors during the multi-stage development of tumors. Ionizing radiation-induced gene mutations constitute the molecular basis for its carcinogenic effects. Clarifying the patterns of mutational signatures induced by ionizing radiation is of great importance for a profound understanding of stochastic effects. This review presents the research history and analytical method of mutational signatures as well as a comprehensive summary of the current status of research on mutational signatures induced by ionizing radiation. The future development of this field is also discussed.

Organ transplantation is the most effective treatment for various types of end-stage diseases. To resolve the problem of donor shortage in organ transplantation, the possibility of xenotransplantation has been gradually explored by surgeons. Pig is one of the common donor sources for xenotransplantation. As a bridge between two species, the viruses carried by pig organs may be transmitted between species and cause the risk of zoonosis. Porcine endogenous retrovirus (PERV) is integrated into the genome, which is a category of retrovirus featuring cross-species transmission. In this article, the influencing factors of transmission characteristics of PERV, the transmission risk of PERV and its recombinant virus, and the detection and transmission risk assessment of PERV in xenotransplantation test were reviewed, aiming to provide reference for alleviating severe shortage of donor organs and driving the advancement of xenotransplantation technologies.

Organ transplantation is the most effective treatment for all categories of end-stage organ diseases. To resolve the shortage of donors in organ transplantation, widespread attention has been diverted to xenotransplantation. At present, clinicians mainly highlight the problems related to xenotransplantation rejection and viral infection. The physiology of xenotransplantation has been rarely studied. Kidney performs endocrine function by producing erythropoietin (EPO), renin and activating vitamin D. Although these pathways are usually well preserved in allogeneic transplantation, species-specific differences, especially those between pigs and non-human primates, may still affect the physiological function of transplant organs. In this article, the changes of EPO, renin-angiotensin-aldosterone system (RAAS) and active vitamin D₃ of pig and human after xenotransplantation were illustrated, aiming to provide reference for subclinical research of xenotransplantation.

With aging population becoming increasingly prominent, more intelligent, integrated, and anthropomorphic nursing robots are becoming an important option for future home-based elderly care. However, a series of ethical dilemmas may arise when nursing robots that provide long-term services participate in the social life of the elderly as social entities. For example, the encroachment of low-level interaction between humans and nursing robots on the high-level interaction between humans, as well as the dispute over the definition of responsibility caused by unclear moral subjects. The value sensitive design theory advocates incorporating value into technical design, and based on its conceptual research, empirical research, and iterative approach, it can be found that the fundamental reason for the above-mentioned ethical dilemma lies in the confusion and dislocation of the ternary nursing relationship among human caregivers, the elderly, and nursing robots. Accordingly, this paper proposed to clarify the user status of the elderly and human caregivers, while nursing robots serve as auxiliary tools to meet the nursing needs of the elderly, protect and enhance the well-being of the elderly.

Postoperative complications of colorectal cancer (CRC) are the main cause of postoperative death and seriously affect the quality of life and survival time of patients. The application of a clinical prediction model for postoperative complications of CRC can help promptly identify high-risk patients. Accordingly, reasonable intervention measures can be actively taken to reduce the incidence of postoperative complications of CRC. A scientific basis can also be provided to improve the prognosis of patients. In this work, literature on the risk-factor analysis and prediction-model construction of postoperative complications of CRC at home and abroad in recent years was collected and reviewed. The evaluation content and efficiency of the clinical prediction models in postoperative complications of CRC were summarized. Their advantages and disadvantages were also analyzed. The purpose of this study was to provide a reference for the subsequent optimization of such models and the development of a strong, clinically practical, and universal risk-screening tool for postoperative complications of CRC.

Objective:To investigate the regulation of transcription factor CCCTC binding factor (CTCF) on the expression of B-cell lymphoma 2 ( Bcl-2) gene in pterygium and its molecular mechanism. Methods:Pterygium tissue samples from 22 primary pterygium patients who underwent pterygium excision combined with autologous limbal stem cell transplantation in The First Hospital of Changsha from June 2017 to February 2019 were collected during the operation as pterygium group.Normal conjunctival tissue from 20 patients with ocular trauma due to conjunctiva rupture, eyeball rupture or eyeball perforation in the same period were collected during the repair of ocular trauma as control group.Real-time PCR and Western blot were used to detect the expression levels of CTCF and Bcl-2 in the two groups.The DNA methylation level of the Bcl-2 promoter in the samples of the two groups was detected by bisulfite sequencing PCR (BSP). Pterygium fibroblasts were isolated and cultured.Fibroblasts were identified by immunohistochemistry using vimentin antibody.The cultured pterygium fibroblasts were divided into a CTCF interference group transfected with CTCF interference plasmid, and a control group transfected with control plasmid.The expression levels of CTCF and Bcl-2 in pterygium fibroblasts in CTCF interference and control groups were detected by real-time PCR and Western blot.The cell vitality was detected with cell counting kit-8 at 12, 24, and 48 hours after transfection.The DNA methylation level of the Bcl-2 promoter in the cells of the CTCF interference and control groups after transfection was determined by BSP.Differences of the indexes among groups were analyzed.Correlation between Bcl-2 mRNA and Bcl-2 gene promoter methylation level of CTCF protein in pterygium tissue was analyzed by Pearson linear correlation analysis.This study protocol was approved by the Ethics Committee of The First Hospital of Changsha (No.KL-2017021). Written informed consent was obtained from the patients from whom the specimens were collected.Results:The relative expression levels of CTCF mRNA and protein in pterygium group were 7.23±3.34 and 0.92±0.21, respectively, which were significantly higher than 1.10±0.44 and 0.28±0.07 in normal conjunctiva group ( t=-8.136, -13.025; both at P<0.01). The relative expression levels of Bcl-2 mRNA and protein in pterygium group were 10.27±4.64 and 0.95±0.27, which were higher than 1.10±0.41 and 0.32±0.14 in normal conjunctiva group, showing statistically significant differences ( t=-8.789, -10.782; both at P<0.01). The CTCF protein expression was significantly positively correlated with the Bcl-2 mRNA expression in pterygium group ( r=0.746, P<0.01). The DNA methylation level of the Bcl-2 promoter in pterygium group was 0.65±0.09, which was lower than 0.83±0.06 in normal conjunctiva group, with a statistically significant difference ( t=7.408, P<0.01). The DNA methylation level was significantly negatively correlated with the Bcl-2 mRNA expression in pterygium group ( r=-0.635, P<0.01). After the interference of CTCF expression in pterygium fibroblasts, the relative expression levels of CTCF and Bcl-2 mRNA in CTCF interference group were 0.37±0.03 and 0.53±0.06, which were significantly lower than 1.02±0.06 and 0.99±0.07 in control group ( t=20.035, 9.029; both at P<0.01). The relative expression levels of CTCF and Bcl-2 proteins in CTCF interference group were 0.23±0.06 and 0.56±0.07, which were lower than 0.52±0.05 and 0.92±0.12 in control group, showing statistically significant differences ( t=6.914, 4.719; both at P<0.01). The cell viability of pterygium fibroblasts in CTCF interference group was 0.10±0.01, 0.17±0.01, 0.38±0.04 at 12, 24, and 48 hours after interference, respectively, which were lower than 0.12±0.01, 0.29±0.01 and 0.85±0.06 in control group, and the differences were statistically significant ( t=3.718, 18.350, 15.621; all at P<0.01). The DNA methylation level of Bcl-2 promoter in CTCF interference group was 0.75±0.04, which was significantly higher than 0.61±0.03 in control group ( t=-4.472, P<0.05). Conclusions:CTCF is excessively expressed in pterygium, which may mediate the overexpression of Bcl-2 through down-regulating DNA methylation level.

Objective:To evaluate incision scars of transaxillary breast augmentation by different methods of scar assessment.Methods:A retrospective study was carried out on 30 patients (age range 20 to 50 years, with mean age of 32 years) who underwent endoscopic assisted transaxillary type Ⅰ dual plane breast implant augmentation by a same surgeon from August 2014 to November 2016. Scars were estimated by 3 methods which included Vancouver Scar Scale (VSS), Visual Assessment Scale (VAS) and patients' questionnaire.Results:VAS score for left side scars ranged from 0 to 8 and the median was 1. VAS score for right side scars ranged from 0 to 8.3 and the median was 1. A total of 48 scars were scored in the 0-2 point range, representing 80% of the 60 total. VSS score for left side scars ranged from 0 to 11.6 and the median was 0.8. VSS score for right side scars ranged from 0 to 11.3 and the median was 1.2. A total of 46 scars were scored in the 0-2 point range, representing 76.7% of the total 60 breats. The scores between VSS and VAS had significant statistical differences ( P<0.001). 80.0% of our patients regarded scars as unconspicuous or basically invisible in our questionnaire. Conclusions:The majority of transaxillary incision scars recover in favorable status with high patients satisfactory rate. VAS is a practical tool for evaluating transaxillary incision scars. The VSS score is not equivalent to the VAS score when grading scars only by photos.

The study aimed to evaluate the safety and function of poly(lactic-acid-co-ε-caprolactone) (PLCL)/fibrinogen nanofibers (P/F-Ns), and provide theoretical basis for the clinical application. The surface morphology, mechanical properties, the hydrophilicity and the fibrinogen content of P/F-Ns were tested by scanning electron microscope, the material testing machine, the contact angle meter and the microplate reader, respectively. The cell adhesion, proliferation and ligament remodeling genes expression of Hig-82 cells on P/F-Ns were conducted through cell counting kit-8 (CCK-8) and real-time quantitative PCR analyses, respectively. The results showed that with the increase of the fibrinogen content, the pore sizes and hydrophilicity of three P/F-Ns increased, but the mechanical properties decreased. Cell adhesion and proliferation tests showed that P/F-N-2 held the best ability to promote cell adhesion and proliferation. The ligament remodeling genes expressions of Hig-82 cells on P/F-N-1, P/F-N-2 and P/F-N-3 were all up-regulated compared to P/F-N-0 on days 3 and 7. All the three P/F-Ns containing fibrinogen (P/F-N-1, P/F-N-2 and P/F-N-3) had better biocompatibility compared to P/F-N-0, and could be efficiently applied to the reconstruction of anterior cruciate ligament.
Anterior Cruciate Ligament Reconstruction ; Cell Adhesion ; Fibrinogen ; Materials Testing ; Nanofibers

OBJECTIVE To exc avate and evaluate the adverse reaction signals of 4 kinds of imported programmed cell death 1 （PD-1）and its ligand （PD-L1）inhibitors，and to guide rational drug use in clinic. METHODS OpenVigil 2.1 software was used to obtain the adverse event reports of four drugs as nivolumab ，pembrolizumab，atezolizumab and durvalumab from the first quarter of 2013 to the fourth quarter of 2020 in the US FDA adverse event reporting system. The reporting odds ratio and proportional reporting ratio were used for signal mining to evaluate new or potential adverse reaction signals. RESULTS A total of 46 840 reports of adverse events with PD- 1/PD-L1 inhibitors as the primary suspected drug were collected ，including 28 896 reports of nivolumab，13 298 reports of pembrolizumab ，3 398 reports of atezolizumab ，and 1 248 reports of durvalumab. From the general characteristics of these reports ，the gender distribution was more men than women ，and the age distribution was mainly in the range of 51-85 years old. The reporting year was mainly in the nearly 4-5 years，and the main reporting countries were the US and Japan，with“death”and“hospitalization or prolonged hospitalization ”as the main serious adverse events which were over 50％ of the whole of 4 kinds of adverse events. A total of 1 597 adverse reaction signals were obtained ，involving 26 systems，focusing on “benign，malignant and unspecified neoplasms （cystic and polypoid tumor ）”，“infections and infestations ”and“investigations”， etc. The analysis of the top 50 adverse reaction signals showed that the largest number of report was endocrine system disease ，the most frequency signal was “malignant neoplasm progression ”and the strongest adverse reaction signal was “radiation pneumonitis ”. And it was also found that 13 adverse reaction signals ，such as “radiation pneumonitis ”“cholangitis”“fulminant type 1 diabetes mellitus” “blood creatine phosphokinase increased ” “disseminated intravascular coagulation ”“cardiac failure ”and “cerebral infarction ”，etc.，were not reported in the drug instructions. CONCLUSIONS PD-1/PD-L1 inhibitors mediate a large number of adverse reaction signals，resulting in high safety risks in “benign，malignant and unspecified neoplasms （cystic and polypoid tumor ）”，“infections and infestations ”and “investigations”，etc. The newly discovered 13 adverse reaction signals ，such as “radiation pneumonitis ”“cholangitis”“blood creatine phosphokinase increased ”“cardiac failure ”and“cerebral infarction ”are of great significance for guiding rational drug use in clinic.