BACKGROUND:Dental pulp stem cells are one of the stem cells with great potential in oral and maxillofacial tissue engineering.Compared with mesenchymal stem cells,dental pulp stem cells have the advantages of convenient collection,less ethical problems and higher potential of proliferation and differentiation.Currently,except for biochemical factors,physical stimulation also plays a critical role in the osteogenic/odontogenic differentiation of dental pulp stem cells. OBJECTIVE:To review the relevant physical factors and the possible signaling pathway affecting the osteogenic/odontogenic differentiation of dental pulp stem cells to find the optimal induction conditions affecting their differentiation. METHODS:PubMed and CNKI databases were searched for relevant articles using"dental pulp stem cells(DPSCs),osteogenesis differentiation,odontoblastic differentiation,hypoxia,mechanical force,laser therapy,magnetic fields,microgravity"as English and Chinese search terms.Seventy-nine articles regarding physical factors affecting osteogenic/odontogenic differentiation of dental pulp stem cells were selected for the review. RESULTS AND CONCLUSION:(1)Direct or indirect physical signals in the microenvironment have shown broad application prospects in regulating the directed differentiation of stem cells.Many related physical factors,for example,hypoxia,mechanical stimulation(dynamic hydrostatic pressure,mechanical tension,shear force,etc.),laser,microgravity,and magnetic field,have positive influences on the osteogenic/odontogenic differentiation of dental pulp stem cells.Owing to the complex mechanical environment of stomatognathic system,mechanical stimulation is a key physical factor in changing cellular environment and is also a frontier in tissue engineering.It will provide new ideas for investigating the response of dental pulp stem cells to the mechanical environment in the diagnosis and treatment of oral diseases.(2)Because this field is relatively"young",the parameters of equipment have not been unified and the relevant results are not consistent.The optimal induction parameters and conditions of related physical factors should be further explored and optimized.(3)Scaffold material,one of the three elements of tissue engineering,plays a role in promoting the osteogenic/odontogenic differentiation of dental pulp stem cells,and promotes the development of materials science and clinical technology.(4)The signaling pathways involve Notch,Wnt,MAPK,etc.The biological basis of regulating the behavior of dental pulp stem cells is not clear.The specific mechanism will be further explored in the future to provide new ideas for dental pulp regeneration and bone tissue engineering under the influence of physical factors.

BACKGROUND:Types II,IIA,and III of Hangman fractures often require surgical treatment,and the selection of surgical methods is controversial.Current surgeries have shortcomings such as incomplete reduction and malunion after surgery.In the early stage,our team used C2-3 lag screws combined with a bucking bar.Intermittent pushing of the C2 vertebral body in the oropharynx has achieved satisfactory clinical results.However,the preliminary studies included few samples and lacked a control group for comparison. OBJECTIVE:To compare the clinical efficacy of posterior C2-3 fixation combined with the bucking bar technique and posterior C2-3 fixation alone in the treatment of unstable Hangman fractures. METHODS:The clinical and imaging data of 55 patients with unstable Hangman fractures who underwent posterior C2-3 internal fixation in Affiliated Hospital of Southwest Medical University were retrospectively analyzed.According to the surgical plan,the patients were divided into two groups.Among them,23 patients received posterior cervical C2-3 internal fixation combined with the bucking bar technique(group A),and 32 patients received simple posterior C2-3 internal fixation(group B).Operation time,intraoperative blood loss,complications,pain visual analog scale score,neck disability index,American Spinal Injury Association classification,and patient satisfaction(Odom's classification)preoperation and during follow-up were compared between the two groups.The changes in C2-3 displacement and angulation and other imaging indicators were compared at each observation time point. RESULTS AND CONCLUSION:(1)There was no statistically significant difference in operation time,intraoperative blood loss,and postoperative complications between the two groups(P>0.05).(2)The neck pain visual analog scale and neck disability index scores of the two groups of patients at the final follow-up were significantly improved compared with those before surgery(P<0.05).The Odom standard classification showed that 21 cases(91%)in group A were excellent and 29 cases(91%)were excellent and good in group B.There was no statistically significant difference in the clinical efficacy indicators between the two groups(all P>0.05).(3)There was no significant difference in C2-3 angulation and displacement between the two groups before operation(P>0.05).Postoperation and at the last follow-up,the angle and displacement of C2-3 in both groups were significantly smaller than before surgery,and the difference was statistically significant(P<0.01).There was no statistically significant difference in the above indicators after surgery and at the last follow-up(P>0.05).After surgery and at the last follow-up,the displacement and angle of C2-3 in group A were significantly smaller than those in group B(P<0.05).(4)At the last follow-up,no patients in group A had residual deformity,and 4 cases(13%,4/32)in group B had residual deformity.(5)Therefore,posterior C2-3 fixation combined with transoral bucking bar technology may be beneficial to the reduction and stabilization of the vertebral body,reduces malunion,and can achieve better reduction.

ObjectiveTo explore the role of cucurbitacin B （CuB） in inducing ferroptosis in 4T1 cells and its mechanism. MethodsThe effects of CuB（0.2， 0.4， 0.8 μmol·L^-1）on the proliferation ability of 4T1 cells in vitro were detected using the methyl thiazolyl tetrazolium （MTT） assay. The clonogenic ability of 4T1 cells was detected by the plate cloning assay， and the levels of lactate dehydrogenase （LDH） in 4T1 cells were detected by the use of a kit. The mitochondrial membrane potential and reactive oxygen species （ROS） levels in 4T1 cells were detected by flow cytometry， and the mitochondrial ultrastructure of 4T1 cells was observed by transmission electron microscopy. The western blot was used to detect the expression of ferroptosis-related protein p53 in 4T1 cells， solute carrier family 7 member 11 （SCL7A11）， glutathione peroxidase 4 （GPX4）， long-chain acyl-CoA synthetase 4 （ACSL4）， transferrin receptor protein 1 （TFR1）， and ferritin heavy chain 1 （FTH1）. ResultsCompared with that in the blank group， the survival rate of 4T1 cells in CuB groups was significantly decreased （P<0.05）， and the number of cell clones in CuB groups was significantly reduced （P<0.01）. In addition， compared with that in the blank group， the leakage of LDH in cells in CuB groups was significantly increased （P<0.01）， and the mitochondrial membrane potential of cells in CuB groups decreased significantly （P<0.01）. Cellular ROS levels were significantly elevated in CuB groups （P<0.01）. The mitochondria of cells in CuB groups were obviously wrinkled， and the mitochondrial cristae were reduced or even disappeared. Compared with that in the blank group， the protein expression of p53， ACSL4， and TFR1 were significantly up-regulated in CuB groups （P<0.05）， and that of SLC7A11， GPX4， and FTH1 were significantly down-regulated （P<0.05）. ConclusionCuB may inhibit SLC7A11 and GPX4 expression by up-regulating the expression of p53， which in turn regulates the p53/SLC7A11/GPX4 signaling pathway axis and accelerates the generation of lipid peroxidation substrate by up-regulating the expression of ACSL4. It up-regulates TFR1 expression to promote cellular uptake of Fe³⁺ and down-regulates the expression of FTH1 to reduce the ability of iron storage， resulting in an elevated free Fe²⁺ level. It catalyzes the Fenton reaction， generates excess ROS， imbalances the antioxidant system and iron metabolism， and then induces ferroptosis in 4T1 cells.

ObjectiveTo explore the role of cucurbitacin B （CuB） in inducing ferroptosis in 4T1 cells and its mechanism. MethodsThe effects of CuB（0.2， 0.4， 0.8 μmol·L^-1）on the proliferation ability of 4T1 cells in vitro were detected using the methyl thiazolyl tetrazolium （MTT） assay. The clonogenic ability of 4T1 cells was detected by the plate cloning assay， and the levels of lactate dehydrogenase （LDH） in 4T1 cells were detected by the use of a kit. The mitochondrial membrane potential and reactive oxygen species （ROS） levels in 4T1 cells were detected by flow cytometry， and the mitochondrial ultrastructure of 4T1 cells was observed by transmission electron microscopy. The western blot was used to detect the expression of ferroptosis-related protein p53 in 4T1 cells， solute carrier family 7 member 11 （SCL7A11）， glutathione peroxidase 4 （GPX4）， long-chain acyl-CoA synthetase 4 （ACSL4）， transferrin receptor protein 1 （TFR1）， and ferritin heavy chain 1 （FTH1）. ResultsCompared with that in the blank group， the survival rate of 4T1 cells in CuB groups was significantly decreased （P<0.05）， and the number of cell clones in CuB groups was significantly reduced （P<0.01）. In addition， compared with that in the blank group， the leakage of LDH in cells in CuB groups was significantly increased （P<0.01）， and the mitochondrial membrane potential of cells in CuB groups decreased significantly （P<0.01）. Cellular ROS levels were significantly elevated in CuB groups （P<0.01）. The mitochondria of cells in CuB groups were obviously wrinkled， and the mitochondrial cristae were reduced or even disappeared. Compared with that in the blank group， the protein expression of p53， ACSL4， and TFR1 were significantly up-regulated in CuB groups （P<0.05）， and that of SLC7A11， GPX4， and FTH1 were significantly down-regulated （P<0.05）. ConclusionCuB may inhibit SLC7A11 and GPX4 expression by up-regulating the expression of p53， which in turn regulates the p53/SLC7A11/GPX4 signaling pathway axis and accelerates the generation of lipid peroxidation substrate by up-regulating the expression of ACSL4. It up-regulates TFR1 expression to promote cellular uptake of Fe³⁺ and down-regulates the expression of FTH1 to reduce the ability of iron storage， resulting in an elevated free Fe²⁺ level. It catalyzes the Fenton reaction， generates excess ROS， imbalances the antioxidant system and iron metabolism， and then induces ferroptosis in 4T1 cells.

Intraoperative cell salvage (IOCS) has been widely applied as an important blood conservation measure in surgical operations. However, there is currently a lack of clinical practice guidelines for the implementation of IOCS in patients with malignant tumors. This report aims to provide clinicians with recommendations on the use of IOCS in patients with malignant tumors based on the review and assessment of the existed evidence. Data were derived from databases such as PubMed, Embase, the Cochrane Library and Wanfang. The guideline development team formulated recommendations based on the quality of evidence, balance of benefits and harms, patient preferences, and health economic assessments. This study constructed seven major clinical questions. The main conclusions of this guideline are as follows: 1) Compared with no perioperative allogeneic blood transfusion (NPABT), perioperative allogeneic blood transfusion (PABT) leads to a more unfavorable prognosis in cancer patients (Recommended); 2) Compared with the transfusion of allogeneic blood or no transfusion, IOCS does not lead to a more unfavorable prognosis in cancer patients (Recommended); 3) The implementation of IOCS in cancer patients is economically feasible (Recommended); 4) Leukocyte depletion filters (LDF) should be used when implementing IOCS in cancer patients (Strongly Recommended); 5) Irradiation treatment of autologous blood to be reinfused can be used when implementing IOCS in cancer patients (Recommended); 6) A careful assessment of the condition of cancer patients (meeting indications and excluding contraindications) should be conducted before implementing IOCS (Strongly Recommended); 7) Informed consent from cancer patients should be obtained when implementing IOCS, with a thorough pre-assessment of the patient's condition and the likelihood of blood loss, adherence to standardized internally audited management procedures, meeting corresponding conditions, and obtaining corresponding qualifications (Recommended). In brief, current evidence indicates that IOCS can be implemented for some malignant tumor patients who need allogeneic blood transfusion after physician full evaluation, and LDF or irradiation should be used during the implementation process.

Objective To compare the mid- and long-term clinical results of mitral valve plasty (MVP) and mitral valve replacement (MVR) in the treatment of functional mitral regurgitation (FMR). Methods Patients with FMR who underwent surgical treatment in the Department of Cardiovascular Surgery of the General Hospital of Northern Theater Command from 2012 to 2021 were collected. The patients who underwent MVP were divided into a MVP group, and those who underwent MVR into a MVR group. The clinical data and mid-term follow-up efficacy of two groups were compared. Results Finally 236 patients were included. There were 100 patients in the MVP group, including 53 males and 47 females, with an average age of (61.80±8.03) years. There were 136 patients in the MVR group, including 72 males and 64 females, with an average age of (61.29±8.97) years. There was no statistical difference in baseline data between the two groups (P＞0.05). There was no statistical difference between the two groups in the extracorporeal circulation time, aortic occlusion time, postoperative hospital and ICU stay, intraoperative blood loss, or hospitalization death (P＞0.05), but the time of mechanical ventilation in the MVP group was significantly shorter than that in the MVR group (P=0.022). The total follow-up rate was 100.0%, the longest follow-up was 10 years, and the average follow-up time was (3.60±2.55) years. There were statistical differences in the left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter and cardiac function between the two groups compared with those before surgery (P<0.05). The postoperative left ventricular ejection fraction in the MVP group was statistically higher than that before surgery (P=0.002), but there was no statistical difference in the MVR group before and after surgery (P=0.658). The left atrial diameter in the MVP group was reduced compared with the MVR group (P=0.026). The recurrence rate of mitral regurgitation in the MVP group was higher than that in the MVR group, and the difference was statistically significant (10.0% vs. 1.5%, P=0.003). There were 14 deaths in the MVP group and 19 in the MVR group. The cumulative survival rate (P=0.605) and cardiovascular events-free survival rate (P=0.875) were not statistically significant between the two groups by Kaplan-Meier survival analysis. Conclusion The safety, and mid- and long-term clinical efficacy of MVP in the treatment of FMR patients are better than MVR, and the left atrial and left ventricular diameters are statistically reduced, and cardiac function is statistically improved. However, the surgeon needs to be well aware of the indications for the MVP procedure to reduce the rate of mitral regurgitation recurrence.

With the widespread adoption of low-dose CT screening and the extensive application of high-resolution CT, the detection rate of sub-centimeter lung nodules has significantly increased. How to scientifically manage these nodules while avoiding overtreatment and diagnostic delays has become an important clinical issue. Among them, lung nodules with a consolidation tumor ratio less than 0.25, dominated by ground-glass shadows, are particularly worthy of attention. The therapeutic challenge for this group is how to achieve precise and complete resection of nodules during surgery while maximizing the preservation of the patient's lung function. The "watershed topography map" is a new technology based on big data and artificial intelligence algorithms. This method uses Dicom data from conventional dose CT scans, combined with microscopic (22-24 levels) capillary network anatomical watershed features, to generate high-precision simulated natural segmentation planes of lung sub-segments through specific textures and forms. This technology forms fluorescent watershed boundaries on the lung surface, which highly fit the actual lung anatomical structure. By analyzing the adjacent relationship between the nodule and the watershed boundary, real-time, visually accurate positioning of the nodule can be achieved. This innovative technology provides a new solution for the intraoperative positioning and resection of lung nodules. This consensus was led by four major domestic societies, jointly with expert teams in related fields, oriented to clinical practical needs, referring to domestic and foreign guidelines and consensus, and finally formed after multiple rounds of consultation, discussion, and voting. The main content covers the theoretical basis of the "watershed topography map" technology, indications, operation procedures, surgical planning details, and postoperative evaluation standards, aiming to provide scientific guidance and exploration directions for clinical peers who are currently or plan to carry out lung nodule resection using the fluorescent microscope watershed analysis method.

AIM:To detect the expression levels of miR-744-5p and E3 ubiquitin protein ligase(PELI3)in conjunctival epithelial cells of perimenopausal patients with dry eye, and analyze their correlation with sex hormone level, inflammatory factor level and tear secretion function.METHODS: A total of 60 perimenopausal patients with dry eye admitted to our hospital from February 2020 to February 2022 were selected as the observation group, in addition, 60 perimenopausal subjects with no abnormal eye examination were included as a control group. The tear film break-up time(BUT), Schirmer I test(SⅠt)and corneal fluorescein staining(FL)scores of perimenopausal patients with dry eye were collected. The conjunctival epithelial cells of the two groups were obtained by impression cytology, the expression level of miR-744-5p was detected by real-time fluorescence quantitative polymerase chain reaction(qRT-PCR), the PELI3 levels of conjunctival epithelial cells and serum levels of follicle stimulating hormone(FSH), estradiol(E2), luteinizing hormone(LH), interleukin-1(IL-1), interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were detected by enzyme-linked immunosorbent assay; correlation analysis was conducted by Pearson and Spearman methods.RESULTS: The expression level of miR-744-5p in conjunctival epithelial cells of patients in the observation group was higher than that in the control group, and the expression level of PELI3 was lower than that in the control group(all P<0.05). Compared with the control group, the expression levels of FSH, IL-1, IL-6 and TNF-α in serum of patients increased in the observation group, and the expression levels of E2 and LH in serum decreased(all P<0.05). Correlation analysis showed that miR-744-5p was negatively correlated with PELI3 in conjunctival epithelial cells of perimenopausal dry eye patients(r=-0.476, P<0.01); miR-744-5p was negatively correlated with LH, E2, BUT and SⅠt(all P<0.05), while it was positively correlated with FSH, IL-1, IL-6, TNF-α and FL scores(all P<0.05); PELI3 was negatively correlated with FSH, IL-1, IL-6, TNF-α and FL scores, while it was positively correlated with E2, BUT and SⅠt(all P<0.05).CONCLUSION: The level of miR-744-5p increased and PELI3 decreased in conjunctival epithelial cells of perimenopausal patients with dry eye. PELI3 and miR-744-5p were closely related to the sex hormones level, inflammatory factor level and the function of tear secretion in perimenopausal patients with dry eye.

AIM:To detect the expression levels of miR-744-5p and E3 ubiquitin protein ligase(PELI3)in conjunctival epithelial cells of perimenopausal patients with dry eye, and analyze their correlation with sex hormone level, inflammatory factor level and tear secretion function.METHODS: A total of 60 perimenopausal patients with dry eye admitted to our hospital from February 2020 to February 2022 were selected as the observation group, in addition, 60 perimenopausal subjects with no abnormal eye examination were included as a control group. The tear film break-up time(BUT), Schirmer I test(SⅠt)and corneal fluorescein staining(FL)scores of perimenopausal patients with dry eye were collected. The conjunctival epithelial cells of the two groups were obtained by impression cytology, the expression level of miR-744-5p was detected by real-time fluorescence quantitative polymerase chain reaction(qRT-PCR), the PELI3 levels of conjunctival epithelial cells and serum levels of follicle stimulating hormone(FSH), estradiol(E2), luteinizing hormone(LH), interleukin-1(IL-1), interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)were detected by enzyme-linked immunosorbent assay; correlation analysis was conducted by Pearson and Spearman methods.RESULTS: The expression level of miR-744-5p in conjunctival epithelial cells of patients in the observation group was higher than that in the control group, and the expression level of PELI3 was lower than that in the control group(all P<0.05). Compared with the control group, the expression levels of FSH, IL-1, IL-6 and TNF-α in serum of patients increased in the observation group, and the expression levels of E2 and LH in serum decreased(all P<0.05). Correlation analysis showed that miR-744-5p was negatively correlated with PELI3 in conjunctival epithelial cells of perimenopausal dry eye patients(r=-0.476, P<0.01); miR-744-5p was negatively correlated with LH, E2, BUT and SⅠt(all P<0.05), while it was positively correlated with FSH, IL-1, IL-6, TNF-α and FL scores(all P<0.05); PELI3 was negatively correlated with FSH, IL-1, IL-6, TNF-α and FL scores, while it was positively correlated with E2, BUT and SⅠt(all P<0.05).CONCLUSION: The level of miR-744-5p increased and PELI3 decreased in conjunctival epithelial cells of perimenopausal patients with dry eye. PELI3 and miR-744-5p were closely related to the sex hormones level, inflammatory factor level and the function of tear secretion in perimenopausal patients with dry eye.

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.