BACKGROUND:Autologous bone,allogeneic bone or artificial bone has been used to promote bone defect repair in the clinic,but the rate of non-healing is still high.The key is to ignore the importance of periosteum in the bone healing process.In the early stage of the project,the project team constructed an electrospinning membrane loaded with vascular endothelial growth factor to highly simulate the intramembranous osteogenesis of natural periosteum at the bone defect site,which promoted bone regeneration to a certain extent.However,the injured area often faces the dilemma of severe inflammatory response mediated by macrophages and lack of seed cells,resulting in the risk of inactivation or diffusion of delivered biological factors.Therefore,it is necessary to further optimize and coordinate the immune regulation and angiogenesis functions of biomimetic periosteum to promote bone repair.OBJECTIVE:To investigate the physicochemical properties of stem cell-engineered bionic periosteum and its role in regulating the inflammatory microenvironment to promote bone repair.METHODS:By combining L-polylactic acid-based microsol electrospinning,type Ⅰ collagen self-assembly and gel stem cell transplantation technology,a bionic periosteum(M@C-B)was constructed,in which the core layer loaded with vascular endothelial growth factor and the shell layer delivered bone marrow mesenchymal stem cells to regulate the immune microenvironment of bone defects.The physicochemical properties of the periosteum were characterized by scanning electron microscopy,transmission electron microscopy,and Fourier transform infrared spectroscopy.A co-culture system was established between the bionic periosteum and macrophages,bone marrow mesenchymal stem cells and human umbilical vein endothelial cells to explore immune regulation and in vitro osteogenic and angiogenic abilities.Finally,the osteogenic properties of the stem cell engineered bionic periosteum were further verified in a rat femoral condyle defect model.RESULTS AND CONCLUSION:(1)Transmission electron microscopy results showed that the micro-sol electrospinning(MS)formed a distinct core-shell structure.Scanning electron microscopy indicated that after the assembly of the collagen-l artificial periosteum(M@C)on the surface of the vascular endothelial growth factor-loaded micro-sol,a distinct"spider web-like"fibrous structure was deposited.Infrared spectroscopy further confirmed the successful self-assembly of collagen-l.Release experiments demonstrated that the M@C group mitigated the burst release phenomenon compared to the MS group,maintaining internal vascular endothelial growth factor activity and sustained release.(2)Live/dead cell staining and CCK-8 assay showed that bone marrow mesenchymal stem cells proliferated well and survived on three types of artificial periosteum:MS,purely aligned poly(L-lactic acid)(PLLA)surface self-assembled collagen-l artificial periosteum(PLLA@C),and vascular endothelial growth factor-loaded micro-sol fiber surface self-assembled collagen-l-bone marrow mesenchymal stem cells artificial periosteum(M@C-B).Among them,the M@C-B group had the highest number of live cells and the fastest proliferation rate.(3)Alkaline phosphatase staining,alizarin red staining,and osteopontin immunofluorescence staining showed that the PLLA@C and M@C-B groups significantly promoted osteogenic differentiation of bone marrow mesenchymal stem cells.Angiogenesis experiments demonstrated that the vascular endothelial growth factor-loaded groups(MS and M@C-B)had longer blood vessel lengths and more reticular vascular-like structures with more cross-linked nodes,with the M@C-B group being the most prominent.(4)Immunofluorescence and flow cytometry showed that artificial periosteum in the M@C-B group significantly inhibited the pro-inflammatory macrophage phenotype and promoted the polarization of macrophages towards the anti-inflammatory M2 phenotype.(5)In vivo studies further confirmed that the M@C-B group showed superior bone mineral density,trabecular thickness,relative bone volume,and trabecular spacing compared to other groups.(6)These results indicate that bone marrow mesenchymal stem cell-engineered artificial periosteum,through the rapid regulation of the bone defect immune microenvironment by the collagen-l-bone marrow mesenchymal stem cells outer phase and the sustained release of vascular endothelial growth factor by the micro-sol electrospinning core-shell structure of the inner phase,synergistically promotes bone healing.

BACKGROUND:Autologous bone,allogeneic bone or artificial bone has been used to promote bone defect repair in the clinic,but the rate of non-healing is still high.The key is to ignore the importance of periosteum in the bone healing process.In the early stage of the project,the project team constructed an electrospinning membrane loaded with vascular endothelial growth factor to highly simulate the intramembranous osteogenesis of natural periosteum at the bone defect site,which promoted bone regeneration to a certain extent.However,the injured area often faces the dilemma of severe inflammatory response mediated by macrophages and lack of seed cells,resulting in the risk of inactivation or diffusion of delivered biological factors.Therefore,it is necessary to further optimize and coordinate the immune regulation and angiogenesis functions of biomimetic periosteum to promote bone repair.OBJECTIVE:To investigate the physicochemical properties of stem cell-engineered bionic periosteum and its role in regulating the inflammatory microenvironment to promote bone repair.METHODS:By combining L-polylactic acid-based microsol electrospinning,type Ⅰ collagen self-assembly and gel stem cell transplantation technology,a bionic periosteum(M@C-B)was constructed,in which the core layer loaded with vascular endothelial growth factor and the shell layer delivered bone marrow mesenchymal stem cells to regulate the immune microenvironment of bone defects.The physicochemical properties of the periosteum were characterized by scanning electron microscopy,transmission electron microscopy,and Fourier transform infrared spectroscopy.A co-culture system was established between the bionic periosteum and macrophages,bone marrow mesenchymal stem cells and human umbilical vein endothelial cells to explore immune regulation and in vitro osteogenic and angiogenic abilities.Finally,the osteogenic properties of the stem cell engineered bionic periosteum were further verified in a rat femoral condyle defect model.RESULTS AND CONCLUSION:(1)Transmission electron microscopy results showed that the micro-sol electrospinning(MS)formed a distinct core-shell structure.Scanning electron microscopy indicated that after the assembly of the collagen-l artificial periosteum(M@C)on the surface of the vascular endothelial growth factor-loaded micro-sol,a distinct"spider web-like"fibrous structure was deposited.Infrared spectroscopy further confirmed the successful self-assembly of collagen-l.Release experiments demonstrated that the M@C group mitigated the burst release phenomenon compared to the MS group,maintaining internal vascular endothelial growth factor activity and sustained release.(2)Live/dead cell staining and CCK-8 assay showed that bone marrow mesenchymal stem cells proliferated well and survived on three types of artificial periosteum:MS,purely aligned poly(L-lactic acid)(PLLA)surface self-assembled collagen-l artificial periosteum(PLLA@C),and vascular endothelial growth factor-loaded micro-sol fiber surface self-assembled collagen-l-bone marrow mesenchymal stem cells artificial periosteum(M@C-B).Among them,the M@C-B group had the highest number of live cells and the fastest proliferation rate.(3)Alkaline phosphatase staining,alizarin red staining,and osteopontin immunofluorescence staining showed that the PLLA@C and M@C-B groups significantly promoted osteogenic differentiation of bone marrow mesenchymal stem cells.Angiogenesis experiments demonstrated that the vascular endothelial growth factor-loaded groups(MS and M@C-B)had longer blood vessel lengths and more reticular vascular-like structures with more cross-linked nodes,with the M@C-B group being the most prominent.(4)Immunofluorescence and flow cytometry showed that artificial periosteum in the M@C-B group significantly inhibited the pro-inflammatory macrophage phenotype and promoted the polarization of macrophages towards the anti-inflammatory M2 phenotype.(5)In vivo studies further confirmed that the M@C-B group showed superior bone mineral density,trabecular thickness,relative bone volume,and trabecular spacing compared to other groups.(6)These results indicate that bone marrow mesenchymal stem cell-engineered artificial periosteum,through the rapid regulation of the bone defect immune microenvironment by the collagen-l-bone marrow mesenchymal stem cells outer phase and the sustained release of vascular endothelial growth factor by the micro-sol electrospinning core-shell structure of the inner phase,synergistically promotes bone healing.

Objective: To design HBV DNA proficiency testing and system comparison samples with different concentration gradients, analyze their detection results in PCR detection systems, evaluate the nucleic acid detection capabilities of laboratories and differences between detection systems, and put forward suggestions for continuous quality improvement to participating laboratories. Methods: Three groups of randomly numbered proficiency testing samples (with HBV DNA reference concentrations of <2, 7.5, and 30 IU/mL respectively) were taken as the detection objects. Using nucleic acid test data from 11 provincial blood station laboratories as the source, the samples were grouped by detection system and laboratory successively, and statistical analysis was conducted. Results: Statistical analysis of the detection data of the three groups of samples based on detection systems and laboratories showed that from low to high concentration, the coincidence rate between the detection results of different detection systems and laboratories and the expected results showed an increasing trend: 38.89%, 85.90%, and 100.00%; the same system exhibited certain differences in performance among different laboratories. Conclusion: Through this proficiency testing and system comparison, it is found that there are certain differences in the detection capabilities of different laboratories and different nucleic acid test systems. Blood station laboratories should standardize processes, strengthen quality management and data analysis on the basis of being familiar with the detection performance of their detection systems, and at the same time strengthen the control of laboratory interference factors to continuously improve the nucleic acid detection capabilities of blood station laboratories.

Objective To investigate the effects of ischemia time and storage periods on RNA quality in fresh-frozen breast cancer(BC)and esophageal cancer(EC)tissue samples in order to establish evidence-based protocols for biobank sample management.Methods The tumor(T)and paired normal(N)tissue samples from 6 cases of BC and 6 cases of EC were collected and cryopreserved in Biobank,Shantou Central Hospital.Mirror paraffin-embedded tissues were simultaneously prepared into sections for morphological analysis.The samples were divided into two groups of<15 min and 15-30 min according to ischemia time,and RNA quality was analyzed at 4 storage periods of 8-10 months(T1),14-16 months(T2),26-28 months(T3)and 38-40 months(T4).Results In 96 analyzed samples,93.8%(90/96)exhibited high quality(RIN≥6),with 89.6%(43/48)in BC and 97.9%(47/48)in EC.Significant differences in RIN were observed between BC group and EC group(8.050 vs.8.600,P=0.009).In EC group,RIN value was significantly negatively correlated with RNA yield(P<0.001).Moreover,RIN values of tumor-normal pairs exhibited markedly significant differences(7.550 vs.9.000,P<0.001).In contrast,no significant difference was detected in BC group(8.200 vs.7.700,P=0.348).Statistical analysis showed that RIN value was positively correlated with 28S/18S(P<0.001),but had no correlation with tumor content(P=0.676)and necrotic content(P=0.055).Neither ischemia time(<15 min vs.15-30 min:8.200 vs.8.300,P=0.932)nor storage periods(T1-T4:8.400,7.700,8.450,8.600,P=0.163)compromised RNA quality.Conclusion Organ origin and tissue type could influence RNA quality of fresh-frozen tissue samples.However,limited ischemia time(≤30 min)and long-term storage period(38-40 months)do not adversely affect RNA quality in fresh-frozen breast cancer and esophageal cancer tissue samples.

Aim To investigate the mechanism of in-testinal mucosal barrier protective effect of Qingjie Huagong decoction(QJHGD)on rats with severe acute pancreatitis(SAP).Methods The SAP rat model was constructed,and the sham-operation group,the model group,the group administered with different dosages of QJHGD,and the positive control group were set up respectively.HE staining was used to observe the histopathological changes.ELISA was employed to detect the serum levels of diamine oxidase(DAO)and D-lactic acid(D-LA)in rats.Transmission electron microscopy was utilized to observe the mitochondria of ileal tissues.qRT-PCR and Western blot were applied to detect the mRNA and protein expression of PGAM5,Drp1,PINK1,Parkin,LC3B in ileal tissues of rats.Results Compared with the sham-operated group,the pancreas and ileum tissues of rats in the model group showed obvious pathological changes,with abnormal mitochondrial structure and reduced number of autoph-agic vesicles in the ileum tissues.The levels of DAO and D-LA in serum increased(P＜0.01),and the mRNA and protein expression of PGAM 5,Drp 1,PINK1,Parkin,and LC3B in the ileum tissues de-creased significantly.Compared with the model group,pancreatic and ileal pathology were improved,mito-chondrial damage in the ileum was reduced,and the number of autophagic vesicles increased in the QJHGD group.The serum levels of DAO and D-LA were re-duced,and the expression of PGAM5,Drp1,PINK1,Parkin,and LC3B mRNA and protein in the ileal tis-sues increased significantly.Conclusions QJHGD may exert a protective effect on the SAP intestinal mu-cosal barrier by regulating the PGAM5/Drp1/PINK1/Parkin axis in order to elevate the level of mitochondri-al autophagy in the intestinal epithelial cells,thereby improving the level of repair of the intestinal epithelial cells.

Aim To study the difference in hepatotox-icity of psoralen on normal rats and Yin-deficiency rats from the perspective of lipid metabolism,so as to help explain the mechanism of psoralen cautiously used in patients with Yin deficiency recorded in ancient books.Methods SD rats were randomly divided into the nor-mal control group(carboxymethyl cellulose-Na,CMC-Na),normal administration group(CMC-Na+psor-alen),Yin-deficiency control group(CMC-Na+thy-roxine)and Yin-deficiency administration group(CMC-Na+thyroxine+psoralen).The model of Yin-deficiency was established by thyroxine(1 mg·kg-1)for ten days,and then psoralen(200 mg·kg-1)was given for three days.The serum indexes related to liver injury were detected by automatic biochemical analy-zer,the morphological changes of liver tissue were ob-served using HE and oil red O staining,and the relative transcription levels of lipid metabolism related enzymes and mRNA of transporter and endoplasmic reticulum stress related factors were detected using Real-time PCR.Results After intragastric administration of psoralen for three days,compared with the normal group,the levels of serum alanine aminotransferase(ALT),aspartate transaminase(AST),total bile acid(TBA)and triglyeride(TG)in Yin deficiency group increased more significantly,while TC,ALB and TP de-creased more significantly,and liver HE and oil red O staining showed more obvious lipid degeneration.TG synthesis factors adrenocortical carcinoma(ACC),fatty acid synthase(FASN)and sterolregulatory element binding protein-1(SREBP-1)were down-regulated more significantly,TG transport factors mili-total pro-tein(MTP)and lipoprotein pipase(LPL)were down-regulated more evidently,fatty acid β-oxidation related factors carnitine palmitoyltransferase 1A(CPT1A),carnitine/organic cation transporter 2(OCTN2)and peroxisome proliferators-activated receptors-alpha(PPARα)were down-regulated more apparently,TC transporter adenosine triphosphate binding cassette transporter G8(ABCG8)and bile acid receptor farne-soid X receptor(FXR)were down-regulated more ob-viously,and endoplasmic reticulum stress factor activa-ting transcription factor 4(ATF4)was up-regulated more significantly.Conclusions Psoralen can cause more severe hepatotoxicity in Yin deficiency rats than that in normal administration group,and its mechanism may be related to the disorder of hepatic lipid metabo-lism,aggravation of hepatic cholestasis and steatosis,and activation of endoplasmic reticulum stress re-sponse.

Aim To explore the therapeutic effect and mechanism of Qingjie Huagong decoction in modulating PI3K/AKT/NF-κB signaling pathway in inflammatory response of acute pancreatitis(AP)mice.Methods Twenty-four mice were randomly divided into Blank group,Model group,Ustekin group,and Qingjie Hua-gong decoction group,with six mice in each group.The AP model was prepared by using rain frogin.Serum α-AMS,PNLP,IL-1β,IL-6,IL-8,IL-18,and TNF-α lev-els were detected by ELISA;the pancreatic pathology was detected by HE staining;the expressions of PI3K,AKT,and NF-κB-related proteins and mRNAs were de-tected by immunohistochemistry,Western blot,and RT-qPCR.Results Compared with the blank group,the model group showed obvious pathological damage to the pancreas,with significantly higher serum α-AMS,PN-LP,IL-1β,IL-6,IL-8,IL-18,and TNF-α levels(P＜0.01),and significantly higher levels of PI3K,AKT,and NF-κB-related proteins and mRNA expression(P＜0.01).Compared with the model group,both the Qingjie Huagong decoction group and the ustekin group improved the histopathological changes in the pancreas of AP mice,decreased the serum α-AMS,PNLP,IL-1β,IL-6,IL-8,IL-18,and TNF-α levels,and down-reg-ulated the expression levels of pancreatic PI3K,AKT,NF-κB-related proteins and mRNA(P＜0.05 or P＜0.01).Conclusion Qingjie Huagong decoction may inhibit the inflammatory response and protect pancreat-ic tissues by regulating the expression of PI3K/AKT/NF-κB signaling pathway.

N6-methyladenosine (m6A) modification, as a widespread and high-profile type of epigenetic modification, can dynamically and reversibly regulate the whole process of RNA metabolism. This modification governs RNA stability, splicing, and translation via m6A regulators, which are categorized as Writers, Erasers, and Readers. m6A modification also plays a critical role in the development of tumors. Disruptions in the homeostasis of m6A modification levels lead to dysregulation of m6A regulators. Consequently, these dysregulated regulators modulate the proliferation, migration, and invasion of tumor cells and interfere with the normal functions of suppressor genes and oncogenes. This article aims to comprehensively elucidate the specific regulatory impacts of m6A modification on tumor-related gene expression. It focuses on the regulatory mechanisms of m6A modification on mRNA stability. Additionally, it explores the influence of m6A on the molecular translation of key signaling pathways. Moreover, it investigates the indirect regulatory effects mediated by non-coding RNAs (ncRNAs), etc. The intention is to offer a novel analysis of the pathogenesis of cancer at a new level, and also provide a theoretical basis for finding new effective treatment methods.

Aim To study the difference in hepatotox-icity of psoralen on normal rats and Yin-deficiency rats from the perspective of lipid metabolism,so as to help explain the mechanism of psoralen cautiously used in patients with Yin deficiency recorded in ancient books.Methods SD rats were randomly divided into the nor-mal control group(carboxymethyl cellulose-Na,CMC-Na),normal administration group(CMC-Na+psor-alen),Yin-deficiency control group(CMC-Na+thy-roxine)and Yin-deficiency administration group(CMC-Na+thyroxine+psoralen).The model of Yin-deficiency was established by thyroxine(1 mg·kg-1)for ten days,and then psoralen(200 mg·kg-1)was given for three days.The serum indexes related to liver injury were detected by automatic biochemical analy-zer,the morphological changes of liver tissue were ob-served using HE and oil red O staining,and the relative transcription levels of lipid metabolism related enzymes and mRNA of transporter and endoplasmic reticulum stress related factors were detected using Real-time PCR.Results After intragastric administration of psoralen for three days,compared with the normal group,the levels of serum alanine aminotransferase(ALT),aspartate transaminase(AST),total bile acid(TBA)and triglyeride(TG)in Yin deficiency group increased more significantly,while TC,ALB and TP de-creased more significantly,and liver HE and oil red O staining showed more obvious lipid degeneration.TG synthesis factors adrenocortical carcinoma(ACC),fatty acid synthase(FASN)and sterolregulatory element binding protein-1(SREBP-1)were down-regulated more significantly,TG transport factors mili-total pro-tein(MTP)and lipoprotein pipase(LPL)were down-regulated more evidently,fatty acid β-oxidation related factors carnitine palmitoyltransferase 1A(CPT1A),carnitine/organic cation transporter 2(OCTN2)and peroxisome proliferators-activated receptors-alpha(PPARα)were down-regulated more apparently,TC transporter adenosine triphosphate binding cassette transporter G8(ABCG8)and bile acid receptor farne-soid X receptor(FXR)were down-regulated more ob-viously,and endoplasmic reticulum stress factor activa-ting transcription factor 4(ATF4)was up-regulated more significantly.Conclusions Psoralen can cause more severe hepatotoxicity in Yin deficiency rats than that in normal administration group,and its mechanism may be related to the disorder of hepatic lipid metabo-lism,aggravation of hepatic cholestasis and steatosis,and activation of endoplasmic reticulum stress re-sponse.

Aim To explore the therapeutic effect and mechanism of Qingjie Huagong decoction in modulating PI3K/AKT/NF-κB signaling pathway in inflammatory response of acute pancreatitis(AP)mice.Methods Twenty-four mice were randomly divided into Blank group,Model group,Ustekin group,and Qingjie Hua-gong decoction group,with six mice in each group.The AP model was prepared by using rain frogin.Serum α-AMS,PNLP,IL-1β,IL-6,IL-8,IL-18,and TNF-α lev-els were detected by ELISA;the pancreatic pathology was detected by HE staining;the expressions of PI3K,AKT,and NF-κB-related proteins and mRNAs were de-tected by immunohistochemistry,Western blot,and RT-qPCR.Results Compared with the blank group,the model group showed obvious pathological damage to the pancreas,with significantly higher serum α-AMS,PN-LP,IL-1β,IL-6,IL-8,IL-18,and TNF-α levels(P＜0.01),and significantly higher levels of PI3K,AKT,and NF-κB-related proteins and mRNA expression(P＜0.01).Compared with the model group,both the Qingjie Huagong decoction group and the ustekin group improved the histopathological changes in the pancreas of AP mice,decreased the serum α-AMS,PNLP,IL-1β,IL-6,IL-8,IL-18,and TNF-α levels,and down-reg-ulated the expression levels of pancreatic PI3K,AKT,NF-κB-related proteins and mRNA(P＜0.05 or P＜0.01).Conclusion Qingjie Huagong decoction may inhibit the inflammatory response and protect pancreat-ic tissues by regulating the expression of PI3K/AKT/NF-κB signaling pathway.