BACKGROUND:Exosomes derived from mesenchymal stem cells play pivotal roles in cell communication and epigenetic regulation due to their low immunogenicity and targeted delivery effects,and have been clinically applied in the treatment of various diseases.OBJECTIVE:To review the isolation,purification,identification methods,and application progress of mesenchymal stem cell-derived exosomes,and to facilitate the development of large-scale preparation techniques and clinical translation of mesenchymal stem cell-derived exosomes.METHODS:The Chinese search terms"exosome,mesenchymal stem cells,isolation,purification,characterization,clinical application"and the English search terms"exosome,extracellular vesicles,mesenchymal stem cells,isolation,characterization,application"were used to search the literature published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating and purifying exosomes,comparing the characteristics of ultracentrifugation,ultrafiltration,size-exclusion chromatography,polymer precipitation,immunoaffinity,microfluidic methods,and other novel approaches based on their underlying principles.(2)Methods for identifying exosomes can be categorized into physical and biochemical analyses,characterizing exosomes based on their shape,size,and characteristic proteins.(3)Mesenchymal stem cell-derived exosomes have broad applications in multiple fields such as medical aesthetics,wound repair,and cancer treatment,due to their immune-regulatory properties and ability to cross biological barriers.(4)The clinical translation of exosomes faces challenges due to their complex structure,lack of universal isolation techniques,and poor stability,making it difficult to achieve in a short period of time.

BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

BACKGROUND:Choline kinase alpha is a key enzyme in phospholipid metabolism,involved in the synthesis of phosphatidylcholine,and plays an important role in maintaining cell membrane integrity and signal transduction.Research has shown that choline kinase alpha is highly expressed in various tumors and is closely related to cell proliferation,metabolic reprogramming,and tumor progression.As a potential therapeutic target,the role of choline kinase alpha in tumor metabolism and mitochondrial function still needs further exploration.OBJECTIVE:To evaluate the effects and the underlying mechanisms of choline kinase alpha on the proliferation and apoptosis of glioma U87MG and U251 cells.METHODS:Short hairpin RNA of choline kinase alpha and its empty vector control were transfected into U87MG and U251 glioma cells.Mitochondrial morphology was observed by transmission electron microscopy.Mitochondrial structure and functional protein levels were assessed by western blot assay.Reactive oxygen species levels in cells were measured using a reactive oxygen species fluorescent probe.Mitochondrial membrane potential was assessed with a JC-1 assay.Intracellular adenosine triphosphate levels were measured by chemiluminescence.Cell proliferation was evaluated using a CCK-8 assay.Apoptosis levels were analyzed by flow cytometry.The mitochondrial fission inhibitor Mdivi-1 was used to protect the mitochondrial function of the choline kinase α-silenced lentiviral cells.Finally,U87MG cells were subcutaneously injected to construct a subcutaneous tumor model in nude mice.The tumor growth in nude mice was observed before and after choline kinase alpha silencing and after the use of the mitochondrial fission inhibitor Mdivi-1.RESULTS AND CONCLUSION:(1)Compared with the empty control group,the mitochondria of U87MG and U251 cells in the choline kinase alpha silencing lentivirus group exhibited significant structural abnormalities in mitochondria,such as vacuolization and cristae disruption.The expressions of mitochondrial structure and function-related proteins TOM20,ACO2,and ATP5A were significantly decreased(P＜0.01,P＜0.001),the expression of SOD2 was significantly increased(P＜0.01,P＜0.000 1),the fluorescence intensity of reactive oxygen species was significantly increased(P＜0.01),the mitochondrial membrane potential and adenosine triphosphate level were significantly decreased(P＜0.01,P＜0.001),the cell proliferation ability was reduced(P＜0.01),and the apoptosis level was increased(P＜0.001).(2)Following Mdivi-1 treatment,the fluorescence intensity of reactive oxygen species in U87MG and U251 cells decreased(P＜0.05,P＜0.01),mitochondrial membrane potential and adenosine triphosphate levels were significantly restored(P＜0.05,P＜0.01,P＜0.001),cell proliferation ability was improved(P＜0.05,P＜0.01),and apoptosis level was decreased(P＜0.05).(3)In addition,the in vitro subcutaneous tumor formation experiment of nude mice showed that compared with the empty control group,the mass and growth rate of subcutaneous tumors formed by U87MG cells in the choline kinase alpha silencing lentivirus group were significantly reduced(P＜0.000 1).After Mdivi-1 treatment,the mass and growth rate of tumors were significantly increased(P＜0.000 1).(4)The results show that choline kinase alpha silencing affects the proliferation and apoptosis of glioma cells by inducing mitochondrial dysfunction.

BACKGROUND:Magnetic nanomaterials,as a hot topic in the biomedical field in recent years,are often used to enhance the targeted delivery of drugs to the affected area.OBJECTIVE:To investigate the effects of magnetic nano drug carriers on skeletal muscle injury markers and inflammatory responses in rats with sports injuries.METHODS:Magnetic nanoparticles were prepared.A total of 88 male SD rats were randomly divided into a blank group(n=8),an injury control group(n=32),a Yunnan Baiyao group(n=24),and a magnetic nano-drug carrier group(n=24)by using a random number table method.The latter three groups were modeled with exercise-induced muscle injury(treadmill slope of-16°,running speed of 16 m/min,and training time of 120 min).Immediately after exercise,after verifying the success of the model,Yunnan Baiyao patch was applied to the gastrocnemius muscle of the rats in the Yunnan Baiyao group.Yunnan Baiyao patch loaded with magnetic nanoparticles was applied to the gastrocnemius muscle of the rats in the magnetic nano-drug carrier group.At 24,48,and 120 hours after exercise,blood was drawn from the abdominal aorta of rats to detect the activities of creatine kinase and lactate dehydrogenase,as well as the levels of myoglobin,interleukin-6,and tumor necrosis factor-α.Hematoxylin-eosin staining was used to observe the infiltration of inflammatory cells in the gastrocnemius muscle.RESULTS AND CONCLUSION:(1)Compared with the blank group,the levels of myoglobin,creatine kinase,lactate dehydrogenase and tumor necrosis factorα in the injury control group at 24,48 and 120 hours after exercise were increased(P＜0.05),and the level of interleukin 6 at 24 and 120 hours after exercise was increased(P＜0.05).Compared with the injury control group,the level of myoglobin in the Yunnan Baiyao group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and lactate dehydrogenase at 24,48 and 120 hours were decreased(P＜0.05),and the levels of interleukin 6 and tumor necrosis factor α at 120 hours after exercise were decreased(P＜0.05).Compared with the Yunnan Baiyao group,the level of myoglobin in the magnetic nano-drug carrier group at 24 and 48 hours after exercise was decreased(P＜0.05),the activities of creatine kinase and tumor necrosis factor α at 48 and 120 hours after exercise were decreased(P＜0.05),and the lactate dehydrogenase activity was reduced(P＜0.05).(2)Hematoxylin-eosin staining showed that a large number of inflammatory cells infiltrated in the muscle fibers of the injury control group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the local damaged muscle fibers began to regenerate 120 hours after exercise.A large number of inflammatory cells infiltrated in the muscle fibers of the Yunnan Baiyao group and the magnetic nano-drug carrier group 24 hours after exercise,and then the inflammatory cell infiltration gradually decreased,and the damaged muscle fibers were regenerating 120 hours after exercise,and there was no significant difference from the blank group.(3)The results show that Yunnan Baiyao patch combined with magnetic nanoparticles can accelerate the recovery of exercise-induced muscle injury in rats,and the effect is better than that of Yunnan Baiyao alone.

BACKGROUND:The previous study of the research group confirmed that Bushen Zhuangjin Decoction can regulate bone metabolism and play an anti-osteoporosis role,and nanocrystalline collagen-based bone can assist in the repair of limb bone defects.OBJECTIVE:To explore the repair effect of nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction on osteoporotic bone defects.METHODS:Totally 84 female SD rats were randomly divided into a sham operation group(n=6,no modeling)and a bilateral ovariectomy group(n=78).After 12 weeks of bilateral ovariectomy,the sham operation group(n=6)and the bilateral ovariectomy group(n=6)were selected for osteoporosis modeling verification.The remaining 72 rats in the bilateral ovariectomy group were randomly divided into 6 intervention groups,with 12 rats in each group:groups A-E had femoral defect models(diameter 3.5 mm,depth 4 mm)established 12 weeks after bilateral ovariectomy.Group A was given double distilled water by gavage(once a day)after surgery;group B was given Bushen Zhuangjin Decoction by gavage(once a day)after surgery;group C had nanocrystalline collagen-based bone filled in the bone defect and then given double distilled water by gavage(once a day);group D had nanocrystalline collagen-based bone filled in the bone defect and then given alendronate sodium by gavage(once a week);group E had nanocrystalline collagen-based bone filled in the bone defect and then given Bushen Zhuangjin Decoction by gavage(once a day);group F had femoral defect models established at the same time after bilateral ovariectomy,and bone defect sites were filled with nanocrystalline collagen-based bone and then given Bushen Zhuangjin Decoction by gavage(once a day).All drugs were given continuously for 12 weeks.12 hours after the last administration,serum levels of type Ⅰ procollagen amino-terminal propeptide,type Ⅰ collagen cross-linked C-terminal peptide,and estradiol were detected;bone volume in the bone defect area was detected by Micro-CT.The expression of type Ⅰ collagen and vascular endothelial growth factor in the bone defect area was detected by immunohistochemical staining.RESULTS AND CONCLUSION:(1)Compared with group A,the serum level of type Ⅰ procollagen amino-terminal propeptide in groups D and E was decreased(P＜0.05).Compared with groups A and C,the serum estradiol level in groups D,E,and F was increased(P＜0.05).There was no significant difference in the bone volume in the defect area between groups A-F(P＞0.05).(2)Immunohistochemical staining showed that compared with group A,the expression of typeⅠ collagen and vascular endothelial growth factor in groups B,D,and E increased(P＜0.05).Compared with group C,the expression of type Ⅰ collagen in groups B,D,E,and F increased(P＜0.05),and the expression of vascular endothelial growth factor in groups D,E,and F increased(P＜0.05).(3)The results show that nanocrystalline collagen-based bone combined with Bushen Zhuangjin Decoction may have the potential to repair bone defects in ovariectomized osteoporotic rats.

BACKGROUND:Currently,there are many modeling methods for pelvic organ prolapse animal models,and the commonly used methods are vaginal balloon dilatation,oophorectomy and the combination of the two.There is no study comparing the three modeling methods in detail.OBJECTIVE:To construct and validate a rat animal model of pelvic organ prolapse using three different methods and to identify the advantages and disadvantages of various models.METHODS:Seventy-two 8-week SPF-grade female Sprague-Dawley rats were selected and randomly divided into four groups,namely,vaginal balloon dilatation group,ovariectomy group,ovariectomy combined with vaginal balloon dilatation group(the combined group),and the sham-operated group(no ovariectomy and no vaginal dilatation).The vaginal wall tissues of rats were collected at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining,EVG staining and immunohistochemical staining of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 detection,and the pelvic floor muscle tissues were taken at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining and EVG staining.RESULTS AND CONCLUSION:(1)Hematoxylin-eosi staining showed that there was no significant difference in the decrease of vaginal epithelial layer thickness in the vaginal balloon dilatation group compared with the sham-operated group,(P＞0.05),while the thickness of the vaginal epithelial layer was significantly reduced in the ovariectomy group and the ovariectomy combined with vaginal balloon dilation group(P＜0.001),and the reduction was more significant in the ovariectomy combined with vaginal balloon dilation group,remained stable at 8 weeks after surgery and lasted until 12 weeks.(2)The changes in the content of collagen fibers and elastic fibers in the vaginal wall stained by Masson and EVG staining were the same as the changes in the thickness of the vaginal epithelial layer stained by hematoxylin-eosin,and there were no changes in collagen fibers and elastic fibers in the pelvic floor muscle tissues of the treatment groups.(3)At 4,8 and 12 weeks after treatment,there was no significant difference in the expression levels of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 in the vaginal wall tissue of the balloon dilation group compared with the control group(P＞0.05),whereas the expression levels of α-smooth muscle actin and Vimentin were significantly decreased in the ovariectomy group and ovariectomy combined with vaginal balloon dilation group(P＜0.01)and the expression of matrix metalloproteinase 9 showed a significant increase(P＜0.01),with a more pronounced increase in the ovariectomy combined with vaginal balloon dilation group,and the increase reached a stable state at 8 weeks after surgery and could persist up to 12 weeks.To conclude,vaginal balloon dilatation could not maintain the degeneration of pelvic organ prolapse formed by the vaginal wall for a long period,and both ovariectomy and the combined method can be used.Ovariectomy combined with vaginal balloon dilatation can significantly accelerate and aggravate the formation of typical histological features of pelvic organ prolapse in vaginal wall tissues,effectively shorten the experimental period,and improve the efficiency.These effects reach a stable state at 8 weeks after surgery and can be sustained up to 12 weeks,which is practical and convenient for the study of pelvic organ prolapse animal models.

BACKGROUND:Acupuncture at Xinshu(BL 15)can significantly improve cardiac function and protect myocardial cells in acute myocardial ischemia,but the effect and mechanism of thread embedding treatment at Xinshu(BL 15)on cardiac function in acute myocardial ischemia are yet unclear.Nuclear factor κB activation often appears as an intranuclear translocation of the P65 isoform,and activation of the nuclear factor κB signaling pathway is marked by elevated P65 levels.OBJECTIVE:To explore the effects of thread embedding pretreatment at Xinshu(BL 15)on cardiac function and the expression levels of interleukin-10,tumor necrosis factor-α,P65 genes and proteins in rats with acute myocardial ischemia.METHODS:Thirty-two male Sprague-Dawley rats were randomly divided into a blank group,a model group,a Xinshu(BL 15)acupoint group,and a non-meridian/non-acupoint group using a random number table method,with eight rats in each group.Rat models of acute myocardial ischemia were established in the latter three groups.The Xinshu(BL 15)acupoint group had thread embedding at Xinshu(BL 15)for 14 days,followed by subcutaneous injection of isoproterenol hydrochloride into the back to establish an acute myocardial ischemia rat model.The non-meridian/non-acupoint group had local thread embedding for 14 days,and the rest procedures were the same as above.In the model group,Xinshu(BL 15)was only marked,and the rest procedures were the same as above.In the blank group,Xinshu(BL 15)was only marked,and then an equal amount of physiological saline was injected subcutaneously into the back.After 24 hours of modeling,electrocardiogram and cardiac ultrasound were performed.Abdominal aorta blood was extracted for detection of serum creatine kinase and creatine kinase isoenzyme levels using enzyme-linked immunosorbent assay.Subsequently,the rats were euthanized and samples were collected.Hematoxylin-eosin and TUNEL staining were used to observe the pathological changes of myocardial tissue and the apoptosis of myocardial cells.Real-time fluorescence quantitative PCR(RT-qPCR)and western blot were used to detect the mRNA and protein expression of tumor necrosis factor-α,interleukin-10,and P65 in myocardial tissue respectively.RESULTS AND CONCLUSION:(1)Electrocardiogram:Compared with the blank group,the model group,non-meridian/non-acupoint group,and Xinshu(BL 15)acupoint group had significantly elevated ST segment in lead Ⅱ of the electrocardiogram.(2)Cardiac ultrasound:Compared with the model group,the Left ventricular end-systolic dimension in the Xinshu(BL 15)acupoint group were significantly reduced(P＜0.05),while left ventricular ejection fraction and left ventricular fractional shortening rate were significantly increased(P＜0.05).(4)Serum creatine kinase and creatine kinase isoenzyme:Compared with the model group,the Xinshu(BL 15)acupoint group showed a significant decrease in serum creatine kinase and creatine kinase isoenzyme levels(P＜0.05).(4)Hematoxylin-eosin staining:Compared with the model group,the arrangement of myocardial fibers in the Xinshu(BL 15)acupoint group was basically neat,with less edema and a small amount of inflammatory cell infiltration.(5)TUNEL staining:Compared with the model group,the fluorescence intensity of myocardial cell apoptosis in the Xinshu(BL 15)acupoint group was significantly reduced,and its apoptosis rate was significantly reduced(P＜0.05).(6)RT-qPCR and western blot:Compared with the model group,the myocardial tissue interleukin-10 level in the Xinshu(BL 15)acupoint group was significantly increased(P＜0.05),while tumor necrosis factor-α and P65 levels were significantly decreased(P＜0.05).These findings indicate that thread embedding pretreatment at Xinshu(BL 15)can improve cardiac function in rats with acute myocardial ischemia,and its mechanism of action may be related to the inhibition of the activation of the nuclear factor-κB signaling pathway.

BACKGROUND:During diabetic wound healing,the sustained activation of M1 macrophages exacerbates the inflammatory response and hinders wound repair.Auranofin,an anti-inflammatory drug,has not been clearly studied for its effects on M1 macrophages and its potential role in diabetic wound healing.OBJECTIVE:To investigate the effects of different concentrations of auranofin on the biological function of M1 macrophages and evaluate its potential application in diabetic wound healing.METHODS:RAW264.7 and THP-1 cells were used as research models.M1 polarization was induced using different concentrations of interferon-γ and lipopolysaccharide.M1 macrophages were treated with 1 and 2 μmol/L auranofin.Cell counting kit-8 assay was used to evaluate the effect of auranofin on cell viability.Quantitative real-time PCR was performed to detect mRNA expression of interleukin-1β,interleukin-6,and tumor necrosis factor-α.ELISA was employed to measure the levels of interleukin-1β,interleukin-6,and tumor necrosis factor-α in the supernatant.Western blot analysis was used to assess the expression of nuclear factor-κB(p65),phosphorylated mitogen-activated protein kinases(MAPK),and total MAPK proteins.Additionally,6-8-week-old male C57BL/6J and db/db diabetic mice were used for wound healing experiments,with the mice divided into C57 control,db/db control and auranofin treatment groups,each containing six animals.Dorsal skin defect modeling and treatment with intraperitoneal injection of auranofin were performed to observe wound healing in mice.RESULTS AND CONCLUSION:(1)Cell experiments showed that co-treatment with interferon-y(10 ng/mL)and lipopolysaccharide(100 ng/mL)significantly induced M1 polarization in RAW264.7 and THP-1 cells,resulting in increased mRNA expression of interleukin-1β,interleukin-6,and tumor necrosis factor-α.Treatment with auranofin(1 and 2 μmol/L)reduced the mRNA expression of these inflammatory factors in the cells and inhibited the secretion of inflammatory factors in the cell supernatant.(2)Auranofin treatment significantly suppressed the activation of nuclear factor-κB(p65)and phosphorylated MAPK signaling pathways.(3)Animal experiments showed that auranofin promoted wound healing in db/db diabetic mice,suggesting that auranofin has strong anti-inflammatory effects and may facilitate the healing of wounds in diabetic mice.

BACKGROUND:Maxillofacial bone three-dimensional(3D)printing technology has been widely used in clinical diagnosis and treatment,but the data source before performing maxillofacial bone 3D printing mainly comes from the CT scanning data.The lens,thyroid and other parts of the human body are extremely sensitive to X-rays;therefore,it is particularly important to effectively reduce the dose of CT radiation when acquiring the data source.OBJECTIVE:To explore the feasibility of low-dose CT technology in optimizing radiation dose for maxillofacial bone 3D printing.METHODS:The medical records of 65 patients who underwent maxillofacial bone 3D printing in the Department of Stomatology at the General Hospital of Northern Theater Command from March 2021 to December 2023 were retrospectively collected and categorized into a conventional CT-dose 3D printing group(conventional CT-dose,120 kVp,automated tube current modulation,n=32)and a low-CT-dose 3D printing group(low-CT-dose group,80 kVp,automated tube current modulation,n=33).The effective dose of radiation was calculated and compared between the two groups.A Likert scale was used to evaluate the quality of 3D printing in the two groups,and the measurement bias and consistency between evaluators were measured using the Bland-Altman method.RESULTS AND CONCLUSION:(1)There was no significant difference in the general demographic characteristics(age,height,weight,body mass,sex,and body mass index)between the two groups(all P＞0.05).(2)The effective dose value of the low CT-dose 3D printing group was(0.3±0.1)mSv,which was about 62.5％lower than that in the conventional CT-dose 3D printing group[(0.8±0.1)mSv].(3)There was no significant difference in the subjective scoring of 3D printing quality between the two groups(all P＞0.05).The subjective consistency among evaluators was good,with Kappa values of 0.85,0.80,and 0.76.The scatter points in the Bland-Altman for both protocols were uniformly distributed within the standard deviation line,indicating good consistency between the two groups.To conclude,low-dose CT technology can be effectively applied in maxillofacial bone 3D printing,reducing radiation dose without affecting the quality of 3D printing.

BACKGROUND:Myocardial hypertrophy often leads to severe cardiovascular diseases and is difficult to diagnose due to its early stages being hard to detect.Circulating inflammatory proteins have been found to be significantly associated with cardiovascular diseases,yet the specific mechanisms linking them to myocardial hypertrophy remain unclear.OBJECTIVE:To investigate the relationship between circulating proteins and myocardial hypertrophy using multiple Mendelian randomization approaches.METHODS:Utilizing data from 91 circulating inflammatory proteins in the GWAS Catalog database and the latest myocardial hypertrophy data from the R11 FinnGen database,we employed bidirectional two-sample Mendelian randomization,multivariate Mendelian randomization,and Genome-Wide Association Studies co-localization to investigate the causal relationship between circulating inflammatory proteins and myocardial hypertrophy.The accuracy of the results was verified through sensitivity tests including MR-PRESSO,Cochran's Q test,MR-Egger intercept assessment,leave-one-out analysis,and funnel plot analysis.RESULTS AND CONCLUSION:In the results of two-sample Mendelian randomization,the primary method used for evaluation was the Inverse Variance Weighting(IVW)approach.It was found that the level of T-cell surface glycoprotein CD6 isoform(IVW:P=0.046,OR=0.74,95％Cl:0.66-1.00),level of slit chemokine(IVW:P=2.1×10-2,OR=0.74,95％CI:0.556-0.95),level of Delta and Notch-like epidermal growth factor-related receptor(IVW:P=3.7×10-4,OR=0.66,95％CI:0.49-0.87),level of interleukin-2(IVW:P=3.8×103,OR=0.667,95％CI:0.50-0.88),and sulfotransferase 1A1(IVW:P=1.42×102,OR=0.80,95％CI:0.67-0.96)had a unidirectional causal effect on cardiac hypertrophy.(2)Among the findings in multivariate Mendelian randomization,the levels of the CD6 isoform of T-cell surface glycoprotein(IVW:P=1.39×102,OR=0.81,95％CI:0.69-0.96)and the levels of Delta and Notch-like epidermal growth factor-related receptor(IVW:P=3.7×10-2,OR=0.73,95％CI:0.55-0.98)were positive,indicating that the results remained significant after excluding the effects of other circulating inflammatory proteins that had an impact on myocardial hypertrophy.(3)In colocalization,T-cell surface glycoprotein CD6 isoform levels had H3+H4=0.96,with the most significant single nucleotide polymorphism being rs59570070,suggesting an intrinsic link between T-cell surface glycoprotein CD6 isoform levels and myocardial hypertrophy.(4)Sensitivity results showed no abnormalities,indicating no heterogeneity or pleiotropic effects influencing the results.(5)These results verified that T cell surface glycoprotein CD6 isoforms,Slit chemokine,Delta and Notch-like epidermal growth factor-related receptors,interleukin-2,and sulfotransferase 1A1 had a unidirectional causal effect on myocardial hypertrophy.T cell surface glycoprotein CD6 isoforms and Delta and Notch-like epidermal growth factor-related receptors had the deepest impact,suggesting that there may be related pathways between T cell surface glycoprotein CD6 isoforms and myocardial hypertrophy.Mendelian randomization studies require large amounts of clinical data and therefore often use European samples from international databases for analysis.Since this analytical method has significant advantages in causal inference,precision medicine,and cross-population validation,its research results still hold great significance for the medical development in China.As Mendelian randomization research deepens,it also promotes the collection and analysis of clinical data in China to some extent.In the future,we can further analyze key protein mechanisms,combine multiomics and clinical validation,develop an inflammatory marker monitoring system and novel anti-inflammatory therapies,thereby promoting the prevention and control of cardiovascular diseases and the development of personalized medicine.