ObjectiveTo establish the fingerprints of 15 batches of Hengzhi Kechuan capsules， to quantitatively analyze 10 index components， and to evaluate the quality uniformity of samples from different batches. MethodsThe fingerprints and quantitative analysis of Hengzhi Kechuan capsules were established by a combination method of high performance liquid chromatography coupled with diode array detector and charged aerosol detector（HPLC-DAD-CAD）， adenosine， guanosine， vanillic acid， safflomin A， agarotetrol， naringin， hesperidin， militarine， ginsenoside Rb₁， and glycyrrhizic acid were selected as quality attribute indexes. A total of 15 batches of Hengzhi Kechuan capsules from 2022 to 2024（3 boxes per batch） were qualitatively and quantitatively analyzed， and the quality uniformity level of the manufacturers was characterized by parameters of intra-batch consistency（P_A） and inter-batch consistency（P_B）. The homogeneity and difference of quality attribute indexes of samples from different years were analyzed by heatmap clustering analysis. ResultsHPLC fingerprints and quantitative method of Hengzhi Kechuan capsules were established， and the methods could be used for qualitative and quantitative analysis of this preparation， which was found to be stable and reliable by method validation. The similarity of fingerprints of 15 batches of samples was 0.887-0.975， a total of 13 common peaks were calibrated， and 10 common peaks were designated， all of which were quality attribute index components. The results of quantitative analysis showed that the contents of the above 10 ingredients in the samples were 0.038-0.078， 0.115-0.251， 0.007-0.018， 0.291-0.673， 0.122-0.257， 0.887-1.905， 1.841-3.364， 1.412-2.450， 2.207-3.112， 0.650-1.161， respectively. And the contents of ginsenoside Rb₁ and glycyrrhizic acid met the limit requirements in the 2020 edition of Chinese Pharmacopoeia. For the samples from 15 batches， the P_A values of the 10 index components were all <10%， indicating good intra-batch homogeneity， and the P_B values ranged from 33.86% to 92.97%， suggesting that the inter-batch homogeneity was poor. Heatmap clustering analysis showed that the samples from different years were clustered into separate categories， and adenosine， guanosine， safflomin A， naringin， hesperidin and agarotetrol were the main differential components. ConclusionThe intra-annual quality uniformity of Hengzhi Kechuan capsules is good and the inter-annual quality uniformity is insufficient， which may be related to the quality difference of Pinellinae Rhizoma Praeparatum， Carthami Flos， Citri Sarcodactylis Fructus， Citri Reticulatae Pericarpium， Aquilariae Lignum Resinatum， Citri Fructus， etc. In this study， the fingerprint and multi-indicator determination method of Hengzhi Kechuan capsules was established， which can be used for more accurate and efficient quality control and standardization enhancement.

ObjectiveTo study the mechanism of compound Xishu granules （CXG） in inhibiting the proliferation of hepatocellular carcinoma cells by regulating ferroptosis. MethodsThe transplanted tumor model of human Huh7 was established with nude mice and the successfully modeled mice were randomized into model， Fufang Banmao （0.21 g·kg^-1）， low-dose （1.87 g·kg^-1） CXG， medium-dose （3.74 g·kg^-1） CXG， and high-dose （7.49 g·kg^-1） CXG groups. Mice were administrated with drinking water or CXG for 28 days， and the body weight and tumor volume were measured every 4 days. Hematoxylin-eosin staining was employed to observe the histopathological changes of tumors. The cell-counting kit-8 （CCK-8） was used to examine the survival rate of Huh7 cells treated with different concentrations （0， 31.25， 62.5， 125， 250， 500， 1 000 mg·L^-1） of CXG for 24 h and 48 h. CA-AM， DCFH-DA， and C11-BODIPY^581/591 fluorescent probes were used to determine the intracellular levels of ferrous ion （Fe²⁺）， reactive oxygen species （ROS）， and lipid peroxide （LPO）， respectively. The colorimetric method was employed to measure the levels of glutathione （GSH） and superoxide dismutase （SOD）. Western blot was employed to determine the protein levels of glutathione peroxidase 4 （GPX4）， transferrin receptor 1 （TFR1）， and ferritin heavy chain 1 （FTH1）， respectively. ResultsIn the animal experiment， compared with the model group， the drug treatment groups showed reductions in the tumor volume from day 12 （P<0.01）. After treatment， the Fufang Banmao and low-， medium-， and high-dose CXG groups had lower tumor volume， relative tumor volume， and tumor weight than the model group （P<0.05）， with tumor inhibition rates of 48.99%， 79.93%， 91.38%， and 97.36%， respectively. Moreover， the CXG groups had lower tumor volume and relative tumor volume （P<0.05 in all the three dose groups） and lower tumor weight （P<0.05 in medium-dose and high-dose groups） than the Fufang Banmao group. Compared with the model group， the drug treatment groups showed reduced number of tumor cells， necrotic foci with karyopyknosis， nuclear fragmentation， and nucleolysis， and the high-dose CXG group showed an increase in the proportion of interstitial fibroblasts. In the cell experiment， compared with the blank group， CXG reduced the survival rate of Huh7 cells in a dose-dependent manner after incubation for 24 h and 48 h （P<0.05）. Compared with the blank group， the RSL3 group and the low-， medium-， and high-dose CXG groups showed a decrease in the relative fluorescence intensity of CA-AM and increases in the fluorescence intensity of DCFH-DA and fluorescence ratio of C11-BODIPY^581/591， which indicated elevations in the levels of Fe²⁺ （P<0.01）， ROS （P<0.05）， and LPO （P<0.01）， respectively. Compared with the blank group， the RSL3 and low-， medium-， and high-dose CXG groups showed lowered levels of GSH and SOD （P<0.05）. In addition， the RSL3 group and the medium- and high-dose CXG groups showed down-regulated expression of GPX4 and FTH1 （P<0.05）， and the low- and high-dose CXG groups presented up-regulated expression of TFR1 （P<0.05）. ConclusionCXG suppresses the proliferation of hepatocellular carcinoma cells by inducing ferroptosis via downregulating the GSH-GPX4 signaling axis and increasing intracellular Fe²⁺and LPO levels.

ObjectiveTo investigate the protective effect of Rehmanniae Radix iridoid glycosides （RIG） on the kidney tissue of streptozotocin （STZ）-induced diabetic mice and explore the underlying mechanism. MethodsTwelve of 72 male C57BL/6J mice were randomly selected as the normal group， and the remaining 60 mice were fed with a high-fat diet for six weeks combined with injection of 60 mg·kg^-1 STZ for 4 days to model type 2 diabetes mellitus. The successfully modeled mice were randomized into model， metformin （250 mg·kg^-1）， catalpol （100 mg·kg^-1）， low-dose RIG （RIG-L， 200 mg·kg^-1） and high-dose RIG （RIG-H， 400 mg·kg^-1） groups （n=11）. Mice in each group were administrated with corresponding drugs， while those in the normal group and model group were administrated with the same dose of distilled water by gavage once a day. After 8 weeks of intervention， an oral glucose tolerance test （OGTT） was performed， and the area under the curve （AUC） was calculated. After mice were sacrificed， both kidneys were collected. The body weight， kidney weight， and fasting blood glucose （FBG） were measured. Biochemical assays were performed to measure the serum levels of triglycerides （TG）， total cholesterol （TC）， serum creatinine （SCr）， and blood urea nitrogen （BUN）. Enzyme-linked immunosorbent assay （ELISA） was employed to determine the serum level of fasting insulin （FINS）， and the insulin sensitivity index （ISI） and homeostatic model assessment for insulin resistance （HOMA-IR） were calculated. The pathological changes in kidneys of mice were observed by hematoxylin-eosin staining and Masson staining. The immunohistochemical method （IHC） was employed to assess the expression of interleukin-1 （IL-1）， interleukin-6 （IL-6）， tumor necrosis factor-α（TNF-α）， transforming growth factor-β₁ （TGF-β₁）， and collagen-3 （ColⅢ） in the kidney tissue. The protein levels of TGF-β₁， cell signal transduction molecule 3 （Smad3）， matrix metalloproteinase-9 （MMP-9）， and ColⅢ in kidneys of mice were determined by Western blot. ResultsCompared with the normal group， the model group showcased decreased body weight and ISI （P<0.01）， increased kidney weight， FBG， AUC， FINS， HOMA-IR， TC， TG， SCr， and BUN （P<0.01）， glomerular hypertrophy， capsular space narrowing， and collagen deposition in the kidney， up-regulated protein levels of IL-1， IL-6， TNF-α， TGF-β₁， ColⅢ， and Smad3 （P<0.01）， and down-regulated protein level of MMP-9 （P<0.01） in the kidney tissue. Compared with the model group， the treatment groups had no significant difference in the body weight and decreased kidney weight （P<0.05， P<0.01）. The FBG level declined in the RIG-H group after treatment for 4-8 weeks and in the metformin， catalpol， and RIG-L groups after treatment for 6-8 weeks （P<0.01）. The AUC in the RIG-L， RIG-H， and metformin groups decreased （P<0.05， P<0.01）. The levels of TC， SCr， and BUN in the serum of mice in each treatment group became lowered （P<0.05， P<0.01）. The level of TG declined in the RIG-L， RIG-H， and metformin groups （P<0.05， P<0.01）. The serum level of FINS declined in the catalpol， RIG-L， and metformin groups （P<0.01）. Compared with the model group， the treatment groups showed decreased HOMA-IR （P<0.01）， increased ISI （P<0.01）， alleviated pathological changes in the kidney tissue， and down-regulated expression of IL-1 and TGF-β₁. In addition， the protein levels of IL-6， TNF-α， and ColⅢ in the RIG-H and metformin groups and IL-6 and TNF-α in the RIG-L group were down-regulated （P<0.05， P<0.01）， and the protein levels of IL-6， TNF-α， and ColⅢ in the catalpol group and ColⅢ in the RIG-L group showed a decreasing trend without statistical difference. The protein levels of TGF-β₁， Smad3， and ColⅢ in the RIG-H and metformin groups were down-regulated （P<0.01）. Compared with that in the model group， the protein level of MMP-9 was up-regulated in each treatment group （P<0.01）. ConclusionRIG can improve the renal structure and function of diabetic mice by regulating the TGF-β₁/Smads signaling pathway.

ObjectiveTo clarify the anti-inflammatory and lung-protective effects of Yantiao prescription on lipopolysaccharide （LPS）-induced acute lung injury （ALI）， and to explore the impact of Yantiao prescription on the metabolic pathways of arachidonic acid （AA） in vivo. MethodsThirty male C57BL/6J mice were randomly divided into the following groups based on body weight： normal group， model group， dexamethasone group （2 mg·kg^-1）， low-dose Yantiao prescription group （18 g·kg^-1）， and high-dose Yantiao prescription group （36 g·kg^-1）， with 6 mice in each group. The ALI mouse model was established by intraperitoneal injection of LPS. The treatment groups received oral gavage once a day for 7 consecutive days， and serum and lung tissue were collected at the end of the experiment. The content of pro-inflammatory cytokines tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， and interleukin-6 （IL-6） in serum was detected by enzyme-linked immunosorbent assay （ELISA）. Hematoxylin-eosin （HE） staining was used to assess lung tissue pathology. The wet/dry weight ratio （W/D） and myeloperoxidase （MPO） activity in lung tissue were measured. The content of AA metabolites in serum and lung tissue was measured by liquid chromatography triple quadrupole-mass spectrometry （LC-MS/MS）. ResultsCompared with the conditions in the normal group， the content of serum pro-inflammatory cytokines TNF-α， IL-1β， and IL-6 in the model group was significantly increased （P<0.01）. The alveolar structure in mice was severely damaged， with markedly thickened alveolar walls and extensive inflammatory cell infiltration. The W/D ratio and MPO activity in lung tissue were significantly increased （P<0.01）. The content of AA metabolites， including prostaglandin D₂ （PGD₂）， prostaglandin E₂ （PGE₂）， 11（S）-hydroxy-eicosatetraenoic acid ［11（S）-HETE］， and 5-hydroxy-eicosatetraenoic acid （5-HETE） in serum and lung tissue was significantly increased （P<0.05）， while the content of 11，12-epoxyeicosatrienoic acid （11，12-EET） and 14，15-epoxyeicosatrienoic acid （14，15-EET） in serum was significantly decreased （P<0.01）. Compared with the results in the model group， the content of serum pro-inflammatory cytokines TNF-α， IL-1β， and IL-6 in the dexamethasone group， low-dose Yantiao prescription group， and high-dose Yantiao prescription group was significantly reduced （P<0.05）. Mild thickening of alveolar walls， scattered inflammatory cell infiltration， and relatively intact tissue structure with improved alveolar architecture were observed. The W/D ratio and MPO activity in lung tissue were significantly reduced （P<0.01）. The content of AA metabolites PGD₂， PGE₂， 11（S）-HETE， and 5-HETE in serum from the dexamethasone group was significantly decreased （P<0.05）， while the content of 14，15-EET in serum significantly increased （P<0.01）， and the content of 5-HETE in lung tissue significantly decreased （P<0.01）. In the low-dose and high-dose Yantiao prescription groups， the content of AA metabolites PGD₂， PGE₂， 11（S）-HETE， and 5-HETE in serum and lung tissue was significantly decreased （P<0.05）， while the content of 11，12-EET in both serum and lung tissue was significantly increased （P<0.05）. ConclusionYantiao prescription has significant protective effects against LPS-induced ALI， which are related to its regulation of AA metabolic pathways in vivo.

Liver cirrhosis is the terminal stage of various chronic liver diseases， with the main clinical manifestation of portal hypertension， which can lead to spontaneous portosystemic shunt （SPSS）. SPSS is very common in clinical practice and is closely associated with the prognosis of patients. This article summarizes the recent studies in the clinical significance of cirrhotic portal hypertension with SPSS， the controversies in studies， and the current status and future prospects and challenges of treatment， in order to provide a reference for the standardized diagnosis and treatment of portal hypertension.

ObjectiveTo explore effect of Xianlian Jiedu prescription on the recurrence of colorectal cancer （CRC） and investigate the related mechanisms. MethodsA postoperative recurrence model was established in 25 Balb/c mice by injecting CT26 cells subcutaneously into the armpit， followed by surgical removal of 99% of the subcutaneous tumor. The mice were randomly divided into model group， low-dose Xianlian Jiedu prescription （XLJDP-L） group （6.45 g·kg^-1·d^-1）， medium-dose Xianlian Jiedu prescription （XLJDP-M） group （12.9 g·kg^-1·d^-1）， high-dose Xianlian Jiedu prescription （XLJDP-H） group （25.8 g·kg^-1·d^-1）， and 5-fluorouracil （5-FU） group （1×10^-3 g·kg^-1·d^-1）. The mice were euthanized after 14 days of continuous intervention， and recurrent tumor tissue was harvested. Hematoxylin and eosin （HE） staining was used to observe pathological and morphological changes in the recurrent tumor tissue. Immunohistochemistry （IHC） was employed to assess the expression of proliferating cell nuclear antigen （Ki67）， vascular endothelial growth factor （VEGF）， and platelet-endothelial cell adhesion molecule （CD31） in recurrent tumor tissue. The Western blot was used to detect the protein expression levels of angiopoietin-2 （ANG-2）， VEGF， phosphorylated-protein kinase B （p-Akt）， protein kinase B （Akt）， phosphorylated-phosphatidylinositol 3-kinase （p-PI3K）， and phosphatidylinositol 3-kinase （PI3K） in recurrent tumor tissue. ResultsBefore treatment， there were no statistical differences in tumor volume， tumor weight， and body mass among the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group compared to the model group， indicating model stability. After treatment， compared with those in the model group， the tumor volume and tumor weight in the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group were significantly reduced （P<0.01）， showing dose dependency. Meanwhile， there were no significant differences in body weight among the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group compared to the model group. HE staining showed that compared with that in the model group， tumor tissue in the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group had loosely arranged cells， increased intercellular spaces， small and shriveled nuclei， light staining， fewer mitotic figures and atypical nuclei， and increased necrotic areas. IHC showed that compared with those of the model group， the positive rates of Ki67， VEGF， and CD31 in the recurrent tumor tissue of the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group were significantly reduced （P<0.01） in a dose-dependent manner. Western blot results showed that compared with those of the model group， the protein expression levels of ANG-2 and VEGF in the recurrent tumor tissue of the XLJDP-L， XLJDP-M， and XLJDP-H groups and the 5-FU group were significantly downregulated （P<0.05， P<0.01）， and the p-Akt/Akt and p-PI3K/PI3K ratios were significantly decreased in a dose-dependent manner （P<0.05， P<0.01）. ConclusionXianlian Jiedu prescription significantly inhibits the recurrence of CRC in mice after subcutaneous tumor surgery. The mechanism may involve regulating the PI3K/Akt pathway and downregulating key angiogenic proteins such as ANG-2， VEGF， and CD31.

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.

BACKGROUND:Ursolic acid can promote the directed differentiation of bone marrow mesenchymal stem cells into osteoblasts.However,there are few reports on whether ursolic acid has osteogenic effect on human periodontal ligament stem cells. OBJECTIVE:To investigate the effect of ursolic acid on proliferation and osteogenic differentiation of human periodontal ligament stem cells. METHODS:The human periodontal ligament stem cells were isolated and cultured.Passage 3 cells were selected and treated with ordinary medium containing different concentrations(0,1,2,4,6,8 μmol/L)of ursolic acid.After intervention for 1,3,5,7 days,the cell proliferation was detected by CCK-8 assay and the appropriate intervention concentration was screened.Passage 3 human periodontal ligament stem cells were treated with osteogenic induction solution containing 0,1,2,4 μmol/L ursolic acid,respectively.After 7 days of intervention,the mRNA expressions of alkaline phosphatase,Runx2,and osteocalcin were detected by qRT-PCR.After 14 days of intervention,the formation of mineralized nodules was observed by alizarin red staining.Passage 3 human periodontal ligament stem cells were taken and the control group was added with osteogenic induction solution;the ursolic acid group and the antagonist group were added with osteogenic induction solution containing ursolic acid(2 μmol/L)and the bone morphogenetic protein signaling pathway antagonist Noggin,respectively.The ursolic acid+antagonist group was added with osteogenic induction solution containing ursolic acid(2 μmol/L)and Noggin,the inhibitor of bone morphogenetic protein signaling pathway,and cultured for 7 days.qRT-PCR and western blot assay were used to detect the mRNA and protein expressions of bone morphogenetic protein 2,Smad1,osteopontin,and Runx2. RESULTS AND CONCLUSION:(1)1,2,4 μmol/L ursolic acid could promote the proliferation of human periodontal ligament stem cells.6,8 μmol/L ursolic acid could inhibit the proliferation of human periodontal ligament stem cells,and 1,2,4 μmol/L ursolic acid was selected to intervene in subsequent experiments.(2)Compared with 0 μmol/L,1,2,4 μmol/L ursolic acid could promote the expression of alkaline phosphatase,Runx2,and osteocalcin mRNA and the formation of mineralized nodules(P<0.05),and the effect of 2 μmol/L ursolic acid was the most significant.(3)Compared with the control group,the mRNA and protein expressions of bone morphogenetic protein 2,Smad1,osteopontin,and Runx2 in the ursolic acid group were increased(P<0.05),while mRNA and protein expressions of the above indexes were decreased in the antagonist group(P<0.05).Compared with the ursolic acid group,mRNA and protein expressions of above indexes were decreased in ursolic acid+antagonist group(P<0.05).(4)The results indicate that ursolic acid promotes osteogenic differentiation of human periodontal ligament stem cells through bone morphogenetic protein signaling pathway.

BACKGROUND:Exosomes derived from mesenchymal stem cells are prospective cell-free alternatives for treating osteoarthritis.Their therapeutic activity and clinical transformation potential can be further improved by adjusting cell culture condition. OBJECTIVE:To review the effect of cell culture conditions on exosome activity and to analyze its clinical transformation potential. METHODS:Articles concerning osteoarthritis/cartilage repair and mesenchymal stem cell-derived exosomes were retrieved on CNKI and PubMed using"exosomes,mesenchymal stem cells,osteoarthritis or cartilage repair"as Chinese search terms and"exosomes or extracellular vesicles,mesenchymal stem cells,osteoarthritis or cartilage repair"as English search terms.The search time was from 2010 to 2023.Finally,100 articles were included for summary and analysis. RESULTS AND CONCLUSION:(1)During cell culture,providing a physical environment favorable for chondrocyte growth or adding chondroprotective small molecules,chondrogenic factors,or inflammatory factors,can further improve the regulatory activity of exosomes secreted by mesenchymal stem cells in maintaining chondrocyte phenotype,promoting cartilage regeneration,and immunosuppression.Therefore,other physical or chemical factors with similar characteristics may also improve the effects of exosomes secreted by mesenchymal stem cells for treating osteoarthritis.(2)Some treatments during cell culture,such as hypoxia induction,pulsed electromagnetic field stimulation,bioreactor,and chondroprotective molecule(e.g.,human parathyroid hormone 1-34)stimulation are safe and scalable,which allows for the production of clinical-grade exosomes secreted by mesenchymal stem cells for osteoarthritis treatment.(3)Mesenchymal stem cell exosomes are expected to achieve modified treatment of osteoarthritis,and the feasibility of clinical transformation can be further improved by adjusting the cell culture regimen to enhance the therapeutic activity.

BACKGROUND:Crosslinked sodium hyaluronate gel has good mechanical property,biocompatibility,and biodegradability,and can be used as an isolated protective material in tumor radiation therapy to protect endangered organs from damage caused by excess radiation dose. OBJECTIVE:To investigate the safety and efficacy of crosslinked sodium hyaluronate gel in reducing the dose of radiation to dangerous organs during brachytherapy. METHODS:A total of 16 specific pathogen-free Kunming mice of the same age and similar body weight were selected as experimental subjects and divided into experimental group and control group by the random number table method,with 8 mice in each group.125I seeds were implanted subcutaneously in the back of mice in the experimental group,and then crosslinked sodium hyaluronate gel was injected around the radioactive particles.Only 125I seeds were implanted subcutaneously in the back of mice in the control group.After injection,the distance between the radioactive particles and the epidermis was measured by spiral CT scan,and the surface radiation dose was measured by radiation dosimeter.Within 10 weeks after injection,the growth state,survival rate,skin radiation damage,and gel retention of mice were observed. RESULTS AND CONCLUSION:(1)Spiral CT scan showed that the implanted gel was relatively concentrated and created an effective distance between the radioactive seeds and the epidermis.The body surface radiation dose of the experimental group was significantly lower than that of the control group(P<0.01).(2)During the experimental observation period,mice in both groups survived;mice in the control group showed obvious irritability and other unstable behavior in the late experimental period,and some mice in the experimental group showed similar behavior.The daily food intake of mice in the two groups had no significant change,and the body mass showed the same increasing trend.After implantation of radioactive seeds,the two groups of mice showed different degrees of radioactive skin injury.From day 23 after injection to the end of the experiment,the skin radiation injury score of the experimental group was lower than that of the control group(P<0.01).At week 10 after implantation,6 mice in the experimental group had no obvious gel residue under their skin,and 2 mice had a very small amount of scattered gel-like samples under their skin.(3)Therefore,the crosslinked sodium hyaluronate injection technique can increase the space between the radioactive target area of 125I seeds and the organ at risk outside the target through physical space occupying,which can effectively reduce the dose of the organ at risk,and play a role in the isolation and protection of the organ at risk.