Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

BACKGROUND:Spleen has the functions of blood storage,hematopoiesis,and immunity.With the increase of age,the structural degeneration and functional decline of spleen lead to the impairment of immune system function,thus accelerating the aging process of the body.The treatment of spleen aging in tree shrews with highly active umbilical cord mesenchymal stem cells has not been reported. OBJECTIVE:To explore the intervention effect and mechanism of highly active umbilical cord mesenchymal stem cells on spleen aging in tree shrews. METHODS:Highly active umbilical cord mesenchymal stem cells were isolated,cultured,and obtained from the umbilical cord tissue of newborn tree shrews by caesarean section.The differentiation abilities of adipogenesis,osteogenesis,and chondrogenesis were detected by three-line differentiation kit.Cell cycle and surface markers were detected by flow cytometry.The second generation of highly active umbilical cord mesenchymal stem cells were transfected with Genechem Green Fluorescent Protein with infection complex values of 100,120,140,160,180,and 200,respectively,to screen the best transfection conditions.After transfection,the fourth generation of highly active umbilical cord mesenchymal stem cells was injected into the tail vein of tree shrews in the elderly treatment group.The young control group and the aged model group were not given special treatment.After 4 months of treatment,the spleen tissue was taken and the structure of the spleen was observed by hematoxylin-eosin staining.β-Galactosidase staining was used to detect the activity of aging-related galactosidase.Immunohistochemical staining was used to detect the expression levels of p21 and p53 proteins.Ki67 and PCNA immunofluorescence staining was used to detect cell proliferation activity.Immunofluorescence staining was used to detect the expression levels of spleen autophagy protein molecules Beclin 1 and APG5L/ATG5.Reactive oxygen species fluorescence staining was used to detect the content of reactive oxygen species in spleen tissue.CD3 immunofluorescence staining was used to detect the change of the proportion of total T lymphocytes.The secretion levels of interleukin 1β and transforming growth factor β1 in spleen were detected by enzyme linked immunosorbent assay.The distribution of highly active umbilical cord mesenchymal stem cells labeled with green fluorescent protein in spleen tissue was observed by DAPI double staining of nucleus. RESULTS AND CONCLUSION:(1)Highly active umbilical cord mesenchymal stem cells grew in a short spindle shape with fish-like growth,with a large proportion of G0/G1 phase,and had the potential to differentiate into adipogenesis,osteogenesis,and chondrogenesis.(2)Multiplicity of infection=140 and transfection for 72 hours were the best conditions for labeling tree shrews highly active umbilical cord mesenchymal stem cells with Genechem Green Fluorescent Protein.(3)Compared with the aged model group,in the aged treatment group,the spleen tissue cells of tree shrews were arranged closely,and the area of white pulp was increased(P<0.01);the boundary between red pulp and white pulp was clear;the proportion of germinal centers did not show statistically significant difference(P>0.05).The activity level of galactosidase related to spleen tissue aging was decreased(P<0.001),and the expression levels of aging protein molecules p21 and p53 were down-regulated(P<0.001).The expression levels of proliferation-related molecules Ki67 and PCNA were up-regulated(P<0.001,P<0.05);expression levels of autophagy-related molecules Beclin 1 and APG5L/ATG5 were up-regulated(P<0.001),and the content of reactive oxygen species decreased(P<0.001),and the proportion of CD3+T cells increased(P<0.05).The secretion level of interleukin 1β in the aging-related secretion phenotype decreased(P<0.001);no significant difference was found in transforming growth factor β1 level(P>0.05).Compared with the young control group,the above indexes were significantly different in the elderly treatment group(P<0.05).(4)Green fluorescent cells labeled with green fluorescent protein were observed in spleen tissue of tree shrews the elderly treatment group by frozen tissue section observation.The results show that intravenous infusion of highly active umbilical cord mesenchymal stem cells can migrate to spleen tissue,inhibit the production of reactive oxygen species,down-regulate the expression of aging-related proteins,induce autophagy,promote cell proliferation,reduce chronic inflammation,and then improve the structure and function of spleen tissue.

Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

ObjectiveTo observe the effects of Xibining （XBN） and adipose stem cell exosome （ADSC-Exos） in the cases of separate or joint application on cartilage degeneration and mitochondrial autophagy and explore its mechanism of action to improve knee osteoarthritis （KOA）. MethodSD rats were divided into a sham operation group （sham group）， a model group， an ADSC-Exos group （Exos group）， an XBN group， and an ADSC-Exos+XBN group （Exos+XBN group）. KOA model was established by using anterior cruciate ligament transection （ACLT）. The pain sensitivity status of rats was evaluated， and the degeneration degree of the knee joint and cartilage tissue was detected by Micro-CT and pathological staining. The expression of p62 and LC3B was observed by immunofluorescence， and the serum levels of TNF-α， IL-1β， IL-6， and IL-15 in rats were detected by ELISA. The Western blot was used to detect the protein expression levels of MMP-3， MMP-13， ADAMTS5， ColⅡ， TIMP， ACAN， PINK1， Parkin， p62， and LC3A/B. ResultCompared with the sham group， rats in the model group showed decreased cold-stimulated foot-shrinkage thresholds and mechanical pain sensitivity thresholds， varying degrees of abrasion and loss of cartilage tissue， degeneration of cartilage tissue， elevated serum IL-1β， IL-6， IL-15， and TNF-α levels （P<0.01）， and increased protein expression of MMP-3， MMP-13， and ADAMTS5 in cartilage tissue. In addition， the protein expression of ColⅡ， TIMP1， and ACAN was decreased （P<0.01）. Compared with the model group， rats in each treatment group showed higher cold-stimulated foot-shrinkage thresholds and mechanical pain sensitivity thresholds， reduced cartilage tissue degeneration， lower serum levels of IL-1β， IL-6， IL-15， and TNF-α （P<0.05，P<0.01）， decreased protein expression of MMP-3， MMP-13， and ADAMTS5， and higher protein expression of Cold， TIMP1， and ACAN in cartilage tissue （P<0.05，P<0.01）. Moreover， the changes were the most obvious in the Exos+XBN group. ConclusionBoth ADSCs-Exos and XBN can increase the level of mitochondrial autophagy in chondrocytes and delay cartilage tissue degeneration by promoting the expression of the PINK1/Parkin signaling pathway， and the combination of the two can enhance the therapeutic effect.

BACKGROUND:Cell derivative is cell-derived bioactive components,including decellularized extracellular matrix,exosome,apoptotic extracellular vesicle,and conditioned medium,has the effects on immune regulation,promoting angiogenesis,bone regeneration,ligament remodeling,and is capable of promoting stem cell chemotherapy,migration,proliferation,and adhesion.Its excellent characteristics make it a promising biomaterial for application and clinical translation in the field of periodontal tissue engineering. OBJECTIVE:To review the characteristics of cell derivatives(decellularized extracellular matrix,exosome,apoptotic extracellular vesicle,and conditioned medium)and its effect and the latest progress in the field of regenerative restoration of periodontal complex tissue structures. METHODS:We searched the articles on CNKI and PubMed databases with the search terms"regeneration,periodontal tissue,tissue engineering,decellularized matrix,exosome,apoptotic extracellular vesicle,condition medium"in Chinese and English,respectively.Finally,76 articles were included for analysis and discussion. RESULTS AND CONCLUSION:(1)Among those four cell derivatives,the decellularized extracellular matrix has the best mechanical properties and fibrous structure,serving as a biomimetic scaffold to provide physiochemical signals and participate in mechanical signaling in periodontal tissue engineering,providing supporting effect suitable for periodontal regeneration.Recently,the development of soluble decellularized extracellular matrix bioinks has enabled the fabrication of regenerative scaffolds for personalized periodontal defects.(2)Exosomes are the simplest cell derivatives that have immunomodulatory capacity,promoting cell migration and differentiation.As a carrier,they can be used to carry target molecules to regulate periodontal regeneration,promote ligament remodeling and bone regeneration,and are suitable for periodontal tissue engineering.(3)Apoptotic vesicles generated from apoptotic cells have a strong immunomodulatory effect and can recruit stem cells and macrophages,which determine the fate of stem cells through signal transduction and can enhance immunomodulation to promote periodontal regeneration.Engineered extracellular vesicle is considered to have the potential to initiate targeted internal immunomodulation.(4)The extraction of conditioned medium is simple and completely noninvasive,which provides essential nutrients and growth factors for tissue regeneration.These components are crucial for successful periodontal regeneration.Therefore,the conditioned medium is especially suitable for studying the interactions between cells in vitro and has an important role in high-throughput detection in the future.

Objective To prepare a nano drug(PFOB@Lip-MMC)with liposome as the carrier,liquid perfluorooc-tyl bromide(PFOB)as core and mitomycin C(MMC)loading on the liposome shell and study its inhibitory effect on the proliferation of human pterygium fibroblasts(HPFs).Methods The thin film dispersion-hydration ultrasonic method was used to prepare PFOB@Lip-MMC and detect its physical and chemical properties.Cell Counting Kit-8,Cam-PI cell viability staining and flow cytometry were employed to detect the impact of different concentrations of PFOB@Lip-MMC on the via-bility of HPFs.DiI fluorescence labeled PFOB@Lip-MMC was used to observe the permeability of the nano drug to HPFs under a laser confocal microscope.After establishing HPF inflammatory cell models,they were divided into the control group(with sterile phosphate-buffered saline solution added),PFOB@Lip group(with PFOB@Lip added),MMC group(with MMC added),PFOB@Lip-MMC group(with PFOB@Lip-MMC added)and normal group(with fresh culture medi-um added)according to the experimental requirements.After co-incubation for 24 h,flow cytometer was used to detect the apoptosis rate of inflammatory cells,and the gene expression levels of interleukin(IL)-1β,prostaglandin E2(PGE2),tumor necrosis factor(TNF)-α and vascular endothelial growth factor(VEGF)in cells were analyzed by PCR.Results The average particle size and Zeta potential of PFOB@Lip-MMC were(103.45±2.17)nm and(27.34±1.03)mV,respec-tively,and its entrapped efficiency and drug loading rate were(72.85±3.28)％and(34.27±2.04)％,respectively.The sustained-release MMC of drug-loaded nanospheres reached(78.34±2.92)％in vitro in a 24-hour ocular surface environ-ment.The biological safety of PFOB@Lip-MMC significantly improved compared to MMC.In terms of the DiI fluorescence labeled PFOB@Lip-MMC,after co-incubation with inflammatory HPFs for 2 h,DiI fluorescence labeling was diffusely dis-tributed in the cytoplasm of inflammatory HPFs.The apoptosis rate of inflammatory HPFs in the PFOB@Lip-MMC group[(77.23±4.93)％]was significantly higher than that in the MMC group[(51.62±3.28)％].The PCR examination results showed that the gene transcription levels of IL-1 β,PGE2,TNF-α and VEGF in other groups were significantly reduced com-pared to the control group and PFOB@Lip group,with the most significant decrease in the PFOB@Lip-MMC group(all P＜0.05).Conclusion In this study,a novel nano drug(PFOB@LIP-MMC)that inhibited the proliferation of HPFs was successfully synthesized,and its cytotoxicity was significantly reduced compared to the original drugs.It has good bio-compatibility and anti-inflammatory effects,providing a new treatment approach for reducing the recurrence rate after pte-rygium surgery.

Objective To compare the clinical effects between sutureless bridge intrascleral fixation and ciliary sul-cus suture suspension of intraocular lens(IOL)1 year postoperatively.Methods In this retrospective study,14 patients(14 eyes)who underwent sutureless bridge intrascleral IOL fixation in the No.988 Hospital of Joint Logistic Support Force of PLA from March 2019 to January 2022 were taken as the intrascleral fixation group and 15 patients(15 eyes)who under-went IOL ciliary sulcus suture suspension in the same period were taken as the suture suspension group.During the 1-year follow-up,the preoperative and postoperative uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA)(logMAR),spherical equivalent(SE),endothelial cell count(ECC),intraocular pressure(IOP)and IOL position were compared between the two groups.Results At 1,6 and 12 months postoperatively,the UCVA in both groups significant-ly increased compared with those before surgery(all P＜0.05),and UCVA in the intrascleral fixation group were better than those in the suture suspension group at all postoperative time points(F=4.560,6.411 and5.373;all P＜0.05).At 1,6 and 12 months postoperatively,there was no significant difference in BCVA in both groups compared with those before surgery(all P＞0.05),but BCVA in the intrascleral fixation group were better than those in the suture suspension group at all postoperative time points(F=6.170,6.957 and 10.624;all P＜0.05).After surgery,eyes in the intrascleral fixation group showed hyperopia drift,while eyes in the suture suspension group showed myopia drift.At 1,6 and 12 months post-operatively,the SE of the intrascleral fixation group were(0.59±0.30)D,(0.57±0.27)D and(0.64±0.29)D,respec-tively,and those of the suture suspension group were(-0.75±0.44)D,(-0.72±0.42)D and(-1.12±0.64)D,re-spectively.At 6 months postoperatively,the ECC of both groups were significantly lower than those before surgery(t=8.579 and 21.929;both P＜0.001).The IOP in both groups were within the normal range preoperatively and stable during the follow-up.The IOL were centrally located without obvious decentration or tilt during the follow-up.In addition,there were no vitreous and retinal complications.Conclusion Both sutureless bridge intrascleral IOL fixation and IOL ciliary sulcus suture suspension can obtain a favorable prognosis of visual acuity with refractive shift,while sutureless bridge in-trascleral fixation shows better clinical outcomes.