BACKGROUND:The self-renewal and multi-directional differentiation of pluripotent stem cells possess the potential to revolutionize people's understanding of biology,medicine,development,and disease.Stem cells play an important role in the early stage of embryonic development,and the study of them could be beneficial to understanding of the basic principles of biological development and tissue or organ formation,exploring the potential mechanisms of various diseases,studying the repair and regeneration of damaged tissues or organs,and promoting drug discovery and personalized treatment. OBJECTIVE:To review the research progress of pluripotent stem cells,summarize and categorize the fundamental types of pluripotent stem cells,and elucidate the lineage situations of various types of pluripotent stem cells in common mammals. METHODS:PubMed,Web of Science,CNKI,and WanFang databases were searched systematically,with the keywords"pluripotent stem cells;embryonic stem cells;induced pluripotent stem cells;expanded potential stem cells;livestock pluripotent stem cells"in English and Chinese.The 99 articles related to mammalian pluripotent stem cells were systematically screened according to inclusion and exclusion criteria,and then reviewed. RESULTS AND CONCLUSION:(1)According to classical theory in mouse embryonic stem cell research,the pluripotent state of stem cells is divided into two forms:na?ve and primed.Na?ve state corresponds to the inner cell mass of pre-implantation embryos before attachment to the uterine wall,while primed state corresponds to the epiblast after implantation.These two states exhibit significant differences in epigenetic features,transcriptional activity,external signal dependency,and metabolic phenotype.It is later discovered that there is an intermediate state between na?ve and primed called formative pluripotency.Therefore,the pluripotency of pluripotent stem cells is a continuous developmental process rather than a unique cell state.(2)In addition to obtaining pluripotent stem cells from the inner cell mass,there are various methods and lineages for acquiring pluripotent stem cells,including embryonic germ cells established using primitive germ cells from mouse embryos,induced pluripotent stem cells created by the dedifferentiation of adult mouse and human fibroblasts with four factors—Oct3/4,Sox2,c-Myc,and Klf4;embryonic stem cell-like cell lines cultured from somatic cell nuclear transfer,parthenogenesis,neonatal or adult testicular or ovarian tissue,very small embryonic-like stem cells derived from various adult tissues and expanded pluripotent stem cells derived from pre-implantation stages.These pluripotent stem cells all share the common characteristics of continuous self-renewal,expressing core pluripotency factors and possessing the ability to differentiate into the three primary germ layers.(3)Currently,pluripotent stem cells are being used for disease modeling to study the mechanisms of various diseases and develop new drugs.Simultaneously,scientists are attempting to use pluripotent stem cells to cultivate various tissues and organs,offering new possibilities for regenerative medicine and transplantation.However,the clinical application of pluripotent stem cells faces safety challenges,including issues of cell mutations and immune rejection.Continual improvement in the methods of generating pluripotent stem cells will make them safer and more efficient for clinical applications.(4)Based on the methods of obtaining and lineage establishment of pluripotent stem cells in mice and humans,various types of pluripotent stem cells have been established in livestock,including embryonic stem cells,induced pluripotent stem cells,germ lineages of pluripotent stem cells,and expanded potential stem cells.Research on livestock pluripotent stem cells opens up new avenues for animal reproduction,breeding,genetic engineering,disease modeling,drug screening,and the conservation of endangered wildlife.

OBJECTIVE To investigate the effects of Qinxiang Qingjie oral liquid(QXQJ)on growth and development after repeated administration of 18 d to postnatal day 4(PND4)rats.METHODS The number and sex of PND2 pups were adjusted using the cross-breeding method.These pups were ran-domly divided into the normal control,QXQJ 3.45,10.35 and 28.05 g·kg-1 groups.PND4,juvenile rats were ig given QXQJ every day,while the normal control group was given pure water,once a day,for 18 d,before observation of 3 weeks was resumed.During the experiment,the general condition,body mass,growth and development,physique,bone,hematology and coagulation of the rats in each group were detected.RESULTS 18 d after continuous administration of QXQJ,there was no obvious effect on the food intake,growth and development,nerve reflex,spontaneous behavior,hematology,coagula-tion,blood biochemistry,immunity,growth hormone,histopathology and other examination indexes of juve-nile rats.From PND5,juvenile rats in the QXQJ 10.35 and 28.05 g·kg-1groups developed yellow-brown soft or loose stools and abdominal distention,but the symptoms generally recovered at PND22.The body mass,top-rump length,tail length and limb length of the juvenile rats in the 28.05 g·kg-1 group were signifi-cantly lower at PND7(P<0.05),but recovered one week after drug withdrawal.The bone mineral specific gravity and bone mineral density of the 28.05 g·kg-1 group were significantly lower than those of the normal control group at PND22(P<0.05),but there was no significant difference at PND42.CONCLU-SION QXQJ can cause such indigestion symptoms as yellow brown soft stool or loose stool and abdominal enlargement in unweaned juvenile rats,thus affecting the physical development indicators of rats,but the symptoms can recover after withdrawal of medication or withdrawal from milk.The no observed adverse effect level(NOAEL)of QXQJ administered to 4-day-old rats for 18 d is 3.45 g·kg-1.

The heterogeneity of exhausted T cells (Tex) is a critical determinant of immune checkpoint blockade therapy efficacy. However, few studies have explored exhausted T cell subpopulations in human cancers. In the present study, we examined samples from two cohorts of 175 patients with head and neck squamous cell cancer (HNSCC) by multiplex immunohistochemistry (mIHC) to investigate two subsets of Tex, CD8⁺PD1⁺TCF1⁺ progenitor exhausted T cells (TCF1⁺Tex^prog) and CD8⁺PD1⁺TCF1^- terminally exhausted T cells (TCF1^-Tex^term). Moreover, fresh tumor samples from 34 patients with HNSCC were examined by flow cytometry and immunohistochemistry to further investigate their properties and cytotoxic capabilities and their correlation with regulatory T cells (Tregs) in the tumor immune microenvironment (TIME). mIHC and flow cytometry analysis showed that TCF1^-Tex^term represented a greater proportion of CD8⁺PD1⁺Tex than TCF1⁺Tex^prog in most patients. TCF1⁺Tex^prog produced abundant TNFα, while TCF1^-Tex^term expressed higher levels of CD103, TIM-3, CTLA-4, and TIGIT. TCF1^-Tex^term exhibited a polyfunctional TNFα⁺GZMB⁺IFNγ⁺ phenotype; and were associated with better overall survival and recurrence-free survival. The results also indicated that larger proportions of TCF1^-Tex^term were accompanied by an increase in the proportion of Tregs. Therefore, it was concluded that TCF1^-Tex^term was the major CD8⁺PD1⁺Tex subset in the HNSCC TIME and that these cells favor patient survival. A high proportion of TCF1^-Tex^term was associated with greater Treg abundance.
CD8-Positive T-Lymphocytes ; Head and Neck Neoplasms/therapy* ; Humans ; Immunotherapy/methods* ; Prognosis ; Programmed Cell Death 1 Receptor ; Squamous Cell Carcinoma of Head and Neck/therapy* ; Tumor Microenvironment ; Tumor Necrosis Factor-alpha

Objective To investigate the effects of miR-129-5p on the proliferation and migration of osteosarcoma cells and the regulation of HMGB1 gene. Methods The expression of miR-129-5p and HMGB1 in osteosarcoma cell line MG-63, Saos-2 and osteoblast hFOB1.19 were detected by RT-PCR and Western blot. Bioinformatics methods were used to predict whether there were binding sites between mir-129-5p and HMGB1 gene. Double luciferase reporter gene system was used to verify the interaction between miR-129-5p and the target gene HMGB1. miR-129-5p mimic and inhibitor were transfected into osteosarcoma cell lines with low and high miR-129-5p expression, respectively, and the transfection efficiency was detected by RT-PCR. After successful transfection, the proliferation and migration of osteosarcoma cell lines were detected by CCK-8 assay, scratch assay and Transwell migration assay, respectively, and Western blot was used to detect the expression of HMGB1 in the transfected osteosarcoma cell lines. Results Expression of miR-129-5p in osteosarcoma cells was lower than that in normal osteoblasts (P < 0.05), and the expression of HMGB1 in osteosarcoma cell lines was higher than that in normal osteoblasts (P < 0.05). There were binding sites between miR-129-5p and HMGB1 genes, and the luciferase activity of HMGB1-WT plasmid group was down-regulated after transfection with miR-129-5p mimic (P < 0.05). Transfection of miR-129-5p mimic significantly increased the expression of miR-129-5p in MG-63 cells (P < 0.05), inhibited the proliferation and migration of MG-63 cells (P < 0.05), and decreased the expression level of HMGB1. After transfection with miR-129-5p inhibitor, the expression of miR-129-5p in Saos-2 cells was significantly decreased (P < 0.05), the proliferation and migration abilities of Saos-2 cells were enhanced (P < 0.05), and the expression level of HMGB1 was also increased. Conclusion miR-129-5p may inhibit the proliferation and migration of osteosarcoma cells through HMGB1 gene.

Objective:The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China.Methods:This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems.Results:According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%).Conclusion:Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

Objective: To investigate the effect of denture stomatitis of selective laser melting (SLM) titanium alloy for removable partial denture frameworks. Methods : Twenty patients with dentition defects in our hospital were divided into two groups according to the different methods of creating a removable partial denture framework: the SLM group and casting group. The success rate, placement rate, masticatory efficiency and incidence of denture stomatitis were compared. Experimental data were analyzed with SPSS20.0. Results : The success rate of the SLM framework group was 100.00%, which was higher than that of the casting group (90.00%) (P ＜ 0.01). The rate of framework placement in the SLM group was slightly lower than that in the casting group (P ＜ 0.05). The masticatory efficiency of the SLM group was higher than that of the casting group (0.783 ± 0.030 vs. 0.699 ± 0.037, P ＜ 0.001). The incidence of denture stomatitis (10.00%) in the SLM group was significantly lower than that in the casting group (30.00%) (P ＜ 0.001). Conclusion SLM is superior to the traditional casting method in mastication efficiency and reducing the incidence of denture stomatitis. This method can meet the clinical requirements, but the accuracy of the long-term stent needs to be improved.

Laparoscopic cholecystectomy is considered the gold standard for the treatment of symptomatic cholecystolithiasis and has become one of the typical representatives of minimally invasive surgery. This article briefly introduces the contraindication and indication for laparoscopic cholecystectomy, commonly used surgical procedures, and possible complications and related treatment methods, emphasizes the improvement of surgical procedure and the development of new equipment for cholecystectomy, and points out the current status, problems, and development trend of laparoscopic cholecystectomy, in order to provide a reference for better application of laparoscopic cholecystectomy in clinical practice.

Objective: To investigate the physical properties of Ti-6Al-4V clasps generated by selective laser melting (SLM) with different construction directions and to compare these clasps with cast clasps, which could provide a basis for fabricating SLM clasps with high precision and excellent mechanical properties. Methods: Ti-6Al-4V clasps were fabricated by SLM at 0 degrees (SLM0 group), 45 degrees (SLM45 group) and 90 degrees (SLM90 group) (n = 12). Twelve clasps were cast by the casting method as the control group. Meanwhile, four metal abutments were cast randomly as the abutments of the four groups. X-ray was used to detect cracks in the clasps of each group. The roughness of the clasps was measured by confocal microscopy, the fitness tests between clasps and abutment were processed by stereomicroscopy, and the microstructure of clasps in each group was observed under a metallographic microscope to evaluate the physical properties. Results : There were 0-8 visible cracks in the casting group but no obvious defects in the SLM groups. The maximum surface roughness was observed in the cast group (18.102 ± 3.762) μm, while the minimum roughness was observed in the SLM90 group (5.942 ± 1.486) μm (P < 0.05). There was no statistically significant difference in surface roughness between the SLM0 group [(8.711 ± 2.378) μm] and the SLM45 group [(8.513 ± 1.161) μm]. Fitness was worst in the casting group [(68.445 ± 14.876) μm] and best in the SLM90 group [(33.417 ± 5.880) μm] (P < 0.05). There was no statistically significant difference in fitness between the SLM0 group [(52.917 ± 12.102) μm] and the SLM45 group [(50.889 ± 7.011) μm]. In addition, the growth direction of the β grains was roughly parallel to the build direction, and acicular α grains were present between β grains. SLM was composed of fine grains, while the cast group had large grains. Conclusions Specimens generated by SLM had finer grains than cast specimens. In addition, SLM90 clasps had the highest fitness and the lowest surface roughness.

Objective: To describe the status of non-steroidal anti-inflammatory drugs (NSAIDs) use in areas with a high incidence of upper gastrointestinal cancer in China. Methods: This study was based on the National Key Research and Development Program of "National Precision Medicine Cohort of Esophageal Cancer" and "Study on Identification and Prevention of High-risk Populations of Gastrointestinal Malignancies (Esophageal cancer, Gastric cancer and Colorectal cancer)" . From January 2017 to August 2018, 212 villages or communities with a high incidence of esophageal cancer or gastric cancer were selected from 12 regions in 6 provinces. A total of 35 910 residents aged between 40 and 69 years old who met the inclusion criteria and signed the informed consent were investigated and enrolled in this study. The use of NSAIDs, demographic characteristics, health-related habits, height, weight, and blood pressure were collected by the questionnaire and physical examination. The status of main NSAIDs (aspirin, acetaminophen and ibuprofen) use with the difference varying in genders, age groups and regions were analyzed by using χ² test and Cochran-Armitage trend analysis method. Results: Of 35 910 subjects, the mean age was (54.6±7.1) years old and males accounted for 43.42% (15 591). The overall prevalence of NSAIDs intake was 4.56% (1 638), but it significantly varied in different provinces (P<0.001). The overall prevalence of NSAIDs intake was 4.87% (1 750) in females, which was significantly higher than that in males 4.24% (1 524) (P<0.001). The prevalence of NSAIDs intake increased with age (P for trend <0.001). As the frequency of NSAIDs intake increased, the incidence of gastrointestinal symptoms, gastrointestinal ulcers and black stools increased (P for trend <0.05 for all). Conclusion The use of NSAIDs is prevalent in some areas with a high incidence of upper gastrointestinal cancer in China. The increased use of NSAIDs may lead to more adverse effects related to the gastrointestinal tract.

BACKGROUND: Poor root canal filling or poor post-core crown restoration can cause microleakage between the implant material and the tooth, leading to secondary infection of the periapical tissue and affecting long-term effect of tooth restoration. OBJECTIVE: To analyze the microleakage in a glucose penetration model when post space preparation is performed with different timing and remaining lengths. METHODS: Eighty-six freshly extracted mandibular premolars from the Orthodontics Department of Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University were randomly divided into eight groups: positive control group (n=10) undertook root canal preparation; negative control group (n=10) undertook root canal preparation and filling but not post space preparation; A1, B1 and C1 groups (n=11 per group) were subjected to root canal filling immediately followed by post space preparation with the filling material of 4 mm, 5 mm, and 6 mm in length, respectively; A2, B2 and C2 groups were subjected to root canal filling and 1 week after filling, the three groups underwent post space preparation with the filling material of 4, 5 and 6 mm in length, respectively. At 48 hours after post space preparation, the integration of root canal wall and filling material was observed by scanning electron microscopy. The glucose microleakage model was used to detect the amount of glucose leaking from the crown to the root in each group. RESULTS AND CONCLUSION: (1) Under the scanning electron microscope, the fillings were most tightly bonded to the root canal wall in C1, while microcracks were most apparent in A2. (2) According to the measurement of glucose penetration model, A2 showed more microleakage than A1 (P < 0.05), B2 showed more microleakage than B1 (P < 0.05), and there was no statistically significant difference between C1 and C2 (P> 0.05). No significant difference was found among A1, B1 and C1 (P> 0.05), B2 showed no statistical difference in the microleakage from A2 and C2 (P> 0.05), but A2 showed more microleakage than C2 (P′ < 0.017). These results indicate that immediate post space preparation is superior to delayed preparation in reducing the microleakage. For immediate post space preparation, the remaining length of the filling material has no effect on the microleakage, but for delayed preparation, the filling material of at least 5 mm in length should be preserved.