Objective To investigate the regulatory role of the programmed cell death protein 1 (PD-1) and its ligand programmed cell death protein ligand 1 (PD-L1) signaling on the subtypes and functions of natural killer (NK) cells at the maternal-fetal interface during the second trimester in mice following Toxoplasma gondii infection during the first trimester. Methods Twelve 6- to 8-week-old female mice of the C57BL/6J strain were divided into a control group and an infection group, of 6 mice in each group. On the 6.5th day of pregnancy (Gd6.5), each pregnant mouse in the infection group was intraperitoneally injected with 150 tachyzoites of the Toxoplasma gondii PRU strain, while mice in the control group were injected with an equal volume of physiological saline. On the 12.5th day of pregnancy (Gd12.5), uterus and placenta tissues were sampled from pregnant mice for pathological observations, and the mRNA expression levels of PD-1, PD-L1, and tumor necrosis factor-α (TNF-α) were quantified in uterus and placenta tissues. The PD-1 and DX5 expression was measured on NK cells at the maternal-fetal interface using flow cytometry. In addition, the in vitro JEG-3 trophoblast cells and NK-92MI cells co-culture system was established as the control group, and the addition of T. gondii tachyzoites in the co-culture system served as the infection group. The PD-1, PD-L1, and DX5 mRNA expression was quantified in cells using real-time fluorescence quantitative reverse transcription PCR (RT-qPCR) assay, and the TNF-α concentration was measured in the cell culture supernatant using enzyme-linked immunosorbent assay (ELISA). Results On Gd12.5, clear and intact cellular structures of placental decidual tissues were seen in pregnant mice in the control group, with no remarkable abnormal changes found in the uterine columnar epithelial cells, and inflammatory cell infiltration and blood stasis at varying degrees were found in uterine and placental tissues from pregnant mice in the infection group. The relative PD-1, PD-L1, and TNF-α mRNA expression was (1.004 ± 0.004), (1.001 ± 0.001), and (1.001 ± 0.001) in uterine tissues from pregnant mice in the control group and (2.480 ± 0.720), (3.355 ± 0.920), and (2.391 ± 0.073) in the infection group, respectively. The relative PD-1, PD-L1, and TNF-α mRNA expression was (1.007 ± 0.010), (1.006 ± 0.006), and (1.001 ± 0.001) in the uterine tissues in the control group and (6.948 ± 1.918), (3.225 ± 1.034), and (1.536 ± 0.150) in the infection group, respectively. The relative PD-1, PD-L1, and TNF-α mRNA expression was higher in both the uterine (t = 3.55, 4.43 and 33.02, all P values < 0.05) and placental tissues (t = 5.36, 3.72 and 6.18, all P values < 0.05) in the infection group than in the control group. Flow cytometry showed that the proportions of PD-1⁺ NK cells, PD-1⁺ DX5⁺ NK cells, and DX5⁺ NK cells were (12.200 ± 1.082)%, (9.373 ± 7.728)%, and (44.000 ± 4.095)% in uterine tissues from pregnant mice in the control group, and (21.733 ± 1.630)%, (18.767 ± 1.242)%, and (73.367 ± 0.611)% in the infection group, respectively. The proportions of PD-1⁺ NK cells, PD-1⁺ DX5⁺ NK cells, and DX5⁺ NK cells were (1.100 ± 0.510)%, (2.277 ± 1.337)%, and (96.167 ± 2.831)% in placental tissues from mice in the control group, and (26.867 ± 9.722)%, (23.433 ± 6.983)%, and (82.467 ± 2.248)% in the infection group, respectively. The proportions of PD-1⁺ NK cells (t = 8.45, P < 0.05) and DX5⁺ NK cells (t = 12.29, P < 0.05) were higher in uterine tissues from pregnant mice in the infection group than in the control group, and no significant difference was seen in the proportion of PD-1⁺ DX5⁺ NK cells (Z = -1.09, P > 0.05). The proportions of PD-1⁺ NK cells (t = 4.58, P < 0.05) and PD-1⁺ DX5⁺ NK cells (t = 5.15, P < 0.05) were higher in placental tissues from pregnant mice in the infection group than in the control group, while the proportion of DX5⁺ NK cells was lower in the infection group than in the control group (t = -6.56, P < 0.05). RT-qPCR assay revealed that the relative PD-1, PD-L1, and DX5 mRNA expression was (1.010 ± 0.005), (1.002 ± 0.003), and (1.001 ± 0.001) in the JEG-3 cells and NK92MI cells co-culture system and (3.638 ± 1.258), (0.397 ± 0.158), and (4.267 ± 1.750) in the control group, and ELISA measured that the TNF-α concentration was higher in the cell culture supernatant in the infection group [(22.056 ± 3.205) pg/mL] than in the control group [(12.441 ± 0.001) pg/mL] (t = 5.20, P < 0.05). The PD-1(t = 3.62, P < 0.05) and DX5 mRNA expression (t = 3.23, P < 0.05) was higher in the infection group than in the control group, and the PD-L1 mRNA expression was lower in the infection group than in the control group (t = -6.63, P < 0.05). Conclusions Following T. gondii infection, both PD-L1 expression and PD-1 expression on DX5⁺ NK cells at the maternal-fetal interface are upregulated in mice during the second trimester; however, the proportion of DX5⁺ NK cells decreases. These findings suggest that PD-1/PD-L1 signaling may suppress NK cell functions by modulating DX5⁺ NK cell subsets.

Psoraleae Fructus （PF） is a non-toxic Chinese herbal medicine， while the liver injury caused by PF has aroused wide concern in recent years. At present， animal experiments and in vitro studies have been carried out to explore the mechanism， targets， and toxic components of PF in inducing liver injury， which， however， have differences compared with the actual conditions in clinical practice， and there are still some potential hepatotoxic components and targets of PF that have not been discovered. With the continuous progress in systems biology， establishing the drug-induced liver injury model and the liver injury prediction model based on network toxicology can reduce the cost of animal experiments， improve the toxicity prediction efficiency， and provide new tools for predicting toxic components and targets. To systematically explain the characteristics of liver injury in the application of PF and explore the potential hepatotoxic components and targets of PF， we reviewed the related articles published by China National Knowledge Infrastructure （CNKI）， Wanfang Data， VIP， and PubMed from 1962 to 2021 and analyzed the characteristics and influencing factors of liver injury caused by PF in the patients. Furthermore， we summarized the chemical components of PF and the components entering blood. By reviewing the mechanism， targets， and components of PF in inducing liver injury that were discovered by in vivo and in vitro experiments， we summarized the known compounds in PF that may cause liver injury. Finally， the current methods for building the prediction model of PF-induced liver injury were summarized， and the predicted toxic components and targets were introduced. The possible factors of PF in causing liver injury were explained from three aspects： clinical characteristics， preclinical studies， and computer-assisted network prediction， which provide a reference for predicting the risk of PF-induced liver injury.

ObjectiveBased on ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS^E） technique， we identified qualitatively the metabolites of aristolochic acid（AAs） in rat in order to analyze the metabolic differences between water extract of Aristolochiae fructus（AFE） and Aristolochic acid Ⅰ（AAⅠ）. MethodSD rats were selected and administered AFE（110 g·kg^-1·d^-1） or AAⅠ（5 mg·kg^-1·d^-1） by oral for 5 days， respectively. Serum， urine and feces were collected after administration. Through sample pretreatment， ACQUITY UPLC BEH C₁₈ column（2.1 mm×100 mm， 1.7 μm） was used with the mobile phase of 0.01% formic acid methanol（A）-0.01% formic acid water（B， containing 5 mmol·L^-1 ammonium acetate） for gradient elution（0-1 min， 10%B； 1-7 min， 10%-75%B； 7-7.2 min， 75%-95%B； 7.2-10.2 min， 95%B； 10.2-10.3 min， 95%-10%B； 10.3-12 min， 10%B） at a flow rate of 0.3 mL·min^-1. Positive ion mode of electrospray ionization（ESI⁺） was performed in the scanning range of m/z 100-1 200. In combination with UNIFI 1.9.4.053 system， the Pathway-MS^E was used to qualitatively analyze and identify the AAs prototype and related metabolites in biological samples（serum， urine and feces）， and to compare the similarities and differences of metabolites in rats in the subacute toxicity test between AFE group and AAⅠ group. ResultCompared with AAⅠ group， 6， 10， 13 common metabolites and 14， 20， 30 unique metabolites were identified in biological samples（serum， urine and feces） of AFE group， respectively. Moreover， the main AAs components always followed the metabolic processes of demethylation， nitrate reduction and conjugation. Compared with common metabolites in AAⅠ group， prototype components of AAⅠ in serum and most metabolic derivatives of AAⅠ［AAⅠa， aristolochic lactam Ⅰ（ALⅠ）a， 7-OHALⅠ and its conjugated derivatives］ in biological samples were significantly increased in AFE group（P<0.05， P<0.01）， except that the metabolic amount of ALⅠ in feces of AFE group was remarkably lowed than that of AAⅠ group（P<0.01）. In addition， a variety of special ALⅠ efflux derivatives were also identified in the urine and feces of the AFE group. ConclusionAlthough major AAs components in AFE all show similar metabolic rules as AAⅠ components in vivo， the coexistence of multiple AAs components in Aristolochiae Fructus may affect the metabolism of AAⅠ， and achieve the attenuating effect by increasing the metabolic effection of AAⅠ and ALⅠ.

In order to cultivate qualified oral clinicians, strengthen examination management, and strictly implement process assessment, Special Training Base of Oral and Maxillofacial Radiology in West China Hospital of Stomatology, Sichuan University, has implemented a whole-process and diversified assessment reform. In the part of process assessment, firstly the students were asked to fill in the workload form to give timely feedback on training and truly reflect attendance records; secondly, the performance of trainees in class was comprehensively evaluated in clinical training and theoretical teaching to improve their ability of comprehensive thinking of clinical problems. In the part of result assessment, the traditional theoretical assessment method was weakened, and the ability of comprehensive clinical research was strengthened. Trainees were guided to choose the topic flexibly and use standardized PPT format, and a comprehensive score was determined after assessment. Experts were invited to give their advice, so as to enhance the clinical confidence and scientific research confidence of trainees and help them expand their learning depth and breadth within the limited training time. The analysis of examination methods and assessment results shows that the "whole-process and diversified" assessment mode can truly reflect the training results of trainees and lay a solid foundation for further improvement and implementation of standardized training.

Objective:To investigate the serotype features of group B Streptococcus (GBS) vaginal colonization in late pregnancies and their relationship with early-onset neonatal GBS disease (GBS-EOD). Methods:Thirty-two strains were isolated from neonates delivered by GBS-positive mothers and hospitalized for GBS-EOD in Xiamen Maternal and Child Care Hospital from June 2016 to June 2018. Another 266 strains were isolated from vaginal samples from randomly selected late pregnant women who received antenatal screening and delivered in the same hospital during the same period with an allocation ratio of 12∶1. A total of 298 strains from mothers and 32 strains from neonates were involved. Every isolate was serotyped with latex agglutination assay. GBS infection caused by eleven serotypes and the correlation between GBS serotypes in late pregnant women and neonatal GBS-EOD were analyzed. Qualitative variables were compared using Chi-square or Fisher's exact test. A correlation analysis was presented by the column contact number C. Multiple analysis of multiple sample rates was performed with Post hoc testing. Differences between groups were analyzed according to the adjusted standardized residual. Results:A total of nine serotypes were identified among the 298 strains isolated from the mothers. The most prevalent serotype wasⅢ [55.0% (164/298)], followed byⅠb [16.4% (49/298)], Ⅰa [11.1% (33/298)], Ⅴ [9.4% (28/298)], Ⅱ [5.0% (15/298)], non-typable [NT, 1.0% (3/298)], and Ⅵ, Ⅷ and Ⅸ [0.7% (2/298) in each]. Neither Ⅳ nor Ⅶ serotype was identified. The 32 strains isolated from neonates with GBS-EOD belonged to five serotypes, which were Ⅲ [18/32 (56.3%)], Ⅰa [8/32 (25.0%)], Ⅰb [3/32 (9.4%)], Ⅱ [2/32 (6.2%)] and Ⅴ [1/32 (3.1%)]. The positive rates of GBS Ⅲ serotype in neonates with pneumonia, sepsis, and meningitis were 6/13, 7/14, and 5/5. However, no statistically significant difference was observed in the distribution of the five serotypes in GBS-EOD neonates ( P=0.654). Thirty neonates (93.7%) were cured, while two (6.3%) died. There were statistically significant differences among neonatal GBS-EOD caused by vertical transmission with Ⅰa, Ⅰb, Ⅱ, Ⅲ and Ⅴ, Ⅵ, Ⅷ, Ⅸ and NT serotypes ( P=0.046, contingency coefficient: 0.183). Further analysis showed that the adjusted absolute value of the standardized residual of serotype Ⅰa was 2.7 (>2), and the difference was statistically significant. However, the adjusted absolute value of the standardized residual of serotype Ⅲ was only 0.1, which was not statistically significant. Conclusions:Serotype Ⅲ is the most prevalent GBS serotype in late pregnant women and GBS-EOD neonates, and also the predominant serotype in infants with early-onset meningitis. Serotype Ⅰa could be highly vertically transmitted, while the virulence of serotypes Ⅲ and Ⅰa strains of GBS are the strongest.

Background:CBX3 is a member of heterochromatin protein family. Recent studies indicated that CBX3 was closely related to lung cancer,osteosarcoma,gastric cancer. Aims:To investigate the expression and clinical significance of CBX3 in colorectal cancer,and explore the potential mechanism. Methods:Thirty colorectal cancer patients from June 2011 to June 2012 at Shanghai Renji Hospital were enrolled. Real-time quantitative PCR and immunohistochemistry were used to determine mRNA and protein expressions of CBX3 in colorectal cancer tissues and corresponding paracancerous tissues, respectively. Human colorectal cancer cell line RKO was transfected with overexpressed plasmid or siRNA of CBX3. Cell proliferation was measured by CCK-8 assay,Western blotting was implemented to determine the protein expressions of CBX3 and p53. Results:The mRNA and protein expressions of CBX3 were significantly increased in colorectal cancer tissues than in corresponding paracancerous tissues. Increased protein expression of CBX3 was closely correlated with tumor size (P ＝ 0. 025 ),lymph node metastasis (P ＝ 0. 013 )and TNM staging (P ＝ 0. 020 ). After intervention with overexpressed plasmid of CBX3,the mRNA and protein expressions of CBX3 were efficiently upregulated in RKO cells, cell proliferation and protein expression of p53 were significantly increased. Meanwhile,the mRNA and protein expressions of CBX3 were efficiently downregulated in RKO cells after knockdown of CBX3,resulting in significantly decreased cell proliferation and protein expression of p53. Conclusions:CBX3 may promote the proliferation of colorectal cancer cells via influencing the expression of p53,thus promoting the progression of colorectal cancer. This indicates that CBX3 has the potential to be a new target for diagnosis and therapy of colorectal cancer.