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.

To introduce the general thinking, guidelines, work objectives and elaboration process of the general technical requirements adopted by volume Ⅳ of the Chinese Pharmacopoeia 2025 Edition, and to summarize and figure out the main characteristics on dosage forms, physico-chemical testing, microbial and biological testing, reference standards and guidelines The newly revised general chapters of pharmacopoeia give full play to the normative and guiding role of the Chinese Pharmacopoeia standard, track the frontier dynamics of international drug regulatory science and the elaboration of monographs, expand the application of state-of-the-art technologies, and steadily promote the harmonization and unification with the ICH guidelines； further enhance the overall capacity of TCM quality control, actively implement the 3 R principles on animal experiments, and practice the concept of environmental-friendly； replace and/or reduce the use of toxic and hazardous reagents, strengthen the requirements of drug safety control This paper aims to provide a full-view perspective for the comprehensive, correct understanding and accurate implementation of general technical requirements included in the Chinese Pharmacopoeia 2025 Edition.

To introduce the general thinking,guidelines,work objectives and elaboration process of the general technical requirements adopted by volume Ⅳ of the Chinese Pharmacopoeia 2025 Edition,and to summarize and figure out the main characteristics on dosage forms,physico-chemical testing,microbial and biological testing,ref-erence standards and guidelines.The newly revised general chapters of pharmacopoeia give full play to the norma-tive and guiding role of the Chinese Pharmacopoeia standard,track the frontier dynamics of international drug regu-latory science and the elaboration of monographs,expand the application of state-of-the-art technologies,and stead-ily promote the harmonization and unification with the ICH guidelines;further enhance the overall capacity of TCM quality control,actively implement the 3 R principles on animal experiments,and practice the concept of environ-mental-friendly;replace and/orreduce the use of toxic and hazardousreagents,strengthen the requirementsofdrug safety control.This paper aims to provide a full-view perspective for the comprehensive,correct understanding and accurate implementation of general technical requirements included in the Chinese Pharmacopoeia 2025 Edition.

Objective To explore the CT and MR features of duodenal stromal tumors(DST).Methods The clinical,imaging and pathological data of patients with pancreaticoduodenal groove(PDG)mass detected by CT and/or MR,and pathologically diagnosed as DST were retrospectively analyzed.All imaging features were analyzed.Results Finally,all 11 patients were included,all of whom presented external mass in descending duodenum with clear boundary.There were 5 patients with irregular mass and 6 patients with circular mass.Two patients showed homogeneous mass on plain CT and MR imaging,while 9 patients presented heterogeneous mass(with varying degrees of calcification,hemorrhage,cystic degeneration,and necrosis),showed heterogeneous density on CT findings or high,low and iso signals on T1WI and T2WI without high signal on diffusion weighted imaging(DWI),and high enhancement on arterial phase,portal venous phase and delayed phase.There were no signs of air accumulation in all masses.Conclusion Stromal tumors commonly present external heterogeneous mass in descending duodenum with clear boundary.Familiarity with its predilection location and corresponding CT and MR findings are helpful for the qualitative diagnosis of DST.

BACKGROUND:Long non-coding RNA(LncRNA)plays an important role in nervous system development and neurological diseases.Previous studies by the research team have demonstrated that human umbilical cord mesenchymal stem cells overexpressing erythropoietin(EPO-MSCs)under ischemic and hypoxic conditions have better neuroprotective functions and significantly activate the expression of LncRNA XIST.Research suggests that XIST is related to the pathogenesis of hypoxic-ischemic encephalopathy,but the role and mechanism of its regulation by EPO-MSCs in protecting ischemic-hypoxic neurons remain unclear.OBJECTIVE:To explore the new mechanism by which LncRNA XIST,in response to EPO-MSC signaling,affects the apoptosis of ischemic-hypoxic SH-SY5Y cells.METHODS:(1)SH-SY5Y cell lines with knockdown of LncRNA XIST(sh-XIST)and negative control(NC-XIST)were constructed through lentiviral transfection.Oxygen-glucose deprivation was used to induce ischemic-hypoxic injury in the cells.Transwell chambers were used to create a non-contact co-culture system with EPO-MSCs,sh-XIST,and NC-XIST ischemic-hypoxic SH-SY5Y cells.Cell proliferation ability was detected using the CCK-8 assay.Cell migration ability was assessed using the scratch assay,and cell apoptosis was measured by flow cytometry.(2)RNA-seq bioinformatics analysis was performed to screen for differentially expressed genes and pathways between sh-XIST and NC-XIST cell lines.Dual-luciferase experiments were used to verify the relationship between miR-124-3p and the target genes XIST and GRIN1.qRT-PCR was conducted to validate the expression levels of downstream miR-124-3p and GRIN1 genes.(3)miR-124-3p inhibitors and mimics were added to verify phenotypic changes in SH-SY5Y cells after ischemic-hypoxic injury and co-culture with EPO-MSCs.RESULTS AND CONCLUSION:(1)Compared with the NC-XIST group,SH-SY5Y cells in the sh-XIST group showed reduced proliferation and migration abilities and increased apoptosis after ischemic-hypoxic injury and co-culture with EPO-MSCs.(2)Dual-luciferase experiments showed that miR-124-3p interacted with the target gene XIST.SH-SY5Y cells transfected with miR-124-3p mimics and co-cultured with EPO-MSCs showed decreased apoptosis after ischemic-hypoxic injury,while SH-SY5Y cells transfected with miR-124-3p inhibitors showed increased apoptosis after co-culture with EPO-MSCs.(3)Transcriptomic sequencing and bioinformatics analysis of sh-XIST revealed significant downregulation of the neuroactive ligand-receptor pathway and the key receptor gene GRIN1 for central nervous system development.(4)Dual-luciferase experiments showed that miR-124-3p interacted with GRIN1.GRIN1 expression was significantly downregulated in the sh-XIST group after ischemic-hypoxic injury compared with the NC-XIST group.These findings indicate that LncRNA XIST promotes GRIN1 expression by upregulating miR-124-3p,thereby reducing cell apoptosis after ischemic-hypoxic injury and co-culture with EPO-MSCs and enhancing proliferation and migration.sh-XIST can block this protective function.

A recombinant adenovirus(rAd)for expression of Mycobacterium tuberculosis(M.tb)c-di-AMP phosphodiesterase CnpB was constructed,and its induced humoral immune response was detected.The codon-optimized gene of M.tb CnpB was cloned into the adenoviral plasmid pcADV.The recombinant plasmid pcADV-CnpB was transfected into HEK293T cells,and expression was detected with Western blot.The recombinant plasmid pcADV-CnpB and the backbone plasmid were co-transfected into HEK293T cells to obtain the recombinant adenovirus rAd-CnpB.rAd-CnpB was amplified in HEK293T cells,and the target protein expression of rAd-CnpB was detected with Western blot and immunofluorescence.Mice were immunized with rAd-CnpB intranasally,and their sera and bronchoalveolar lavage fluid(BALF)were collected.ELISA was used to detect levels of antigen-specific antibodies.Restriction enzyme digestion and sequencing indicated that the recombinant plasmid pcADV-CnpB was successfully constructed and led to protein expression in eukaryotic cells.rAd-CnpB was packaged and produced in HEK293T cells.After amplification and purification,rAd-CnpB with a titer of 5.53×1010 PFU/mL was obtained.rAd-CnpB led to CnpB expression in HEK293T cells.Intranasal immunization with rAd-CnpB increased levels of IgG and secretory IgA in BALF and led to high levels of IgG in sera.rAd-CnpB,the recombinant adenovirus for expression of c-di-AMP phosphodiesterase CnpB was successfully constructed,and was found to induce antigen-specific humoral and mucosal immune responses through mucosal immunization.Thus,rAd-CnpB may be used in further research on new TB vaccine strategies.

Objective:To investigate the clinical features and multi-slice spiral computed tomography(CT)imaging features of acute appendicitis in soldiers who have been living in plateau for a long time.Methods:The clinical features and imaging data of 56 cases of acute appendicitis in soldiers who have been living in plateau for a long time confirmed by surgery from February 2022 to August 2024 were retrospectively analyzed.Results:In 56 cases with acute appendicitis in soldiers who have been living in plateau for a long time,the appendectomy position results showed:anterior ileum 4 cases(7.14％),lower ileum 10 cases(17.86％),posterior cecum 16 cases(28.57％),lower cecum 9 cases(16.07％),lateral cecum 2 cases(3.58％),posterior ileum 6 cases(10.71％),high(subhepatic)9 cases(16.07％),and left lower abdominal 0 cases,retroperitoneal appendicitis 0 cases,which was suggested that the anatomical position variation of appendicitis in soldiers with acute appendicitis who have been living at high altitude for a long time was relatively large.The direct manifestations of multi-slice spiral CT showed:appendectomy enlarged diameter＞6 mm in 49 cases(87.50％),appendicular wall thickening＞2 mm in 42 cases(75.00％),ppendiceal dilation lumen and effusion in 29 cases(51.79％),appendix indistinctness in 3 cases(5.36％),lppendix fecalith:27 cases(48.21％),gas in the appendix in 16 cases(28.57％).Indirect findings of multi-slice spiral CT showed that,periappendiceal exudation with shadow in 32 cases(57.14％),appendiceal cellulitis with peripheral abscess in 9 cases(16.07％),peritonitis and ascites in 13 cases(23.21％),ileocecal intestinal wall thickening in 22 cases(39.29％),mesenteric lymph node enlargement in 16 cases(28.57％),reflexive intestinal stasis in ileocecal region was observed in 19 cases(33.93％).Conclusion:In the officers and soldiers with acute appendicitis who lived at high altitude for a long time,multi-slice spiral CT showed the direct manifestations of appendiceal thickening,tube wall thickening,lumen dilatation,fluid accumulation,etc.,and the indirect manifestations were periappendiceal exudation with shadow,appendiceal cellulitis with peripheral abscess,ileocecal intestinal wall thickening,reflexes of small intestine and mesenteric lymph node enlargement.Multi-slice spiral CT has the advantages of clear and intuitive,high safety,high resolution and simple operation in the diagnosis of acute appendicitis.

Objective:To investigate the protective effect of a composite hydrogel against hydrogen peroxide(H2O2)-induced oxidative stress injury in the cardiomyocytes,and to clarify its possible mechanism.Methods:The mice were subcutaneously injected with 100 μL of hydrogel.After normal feeding for 1,14,and 28 d,the mice were sacrificed.Tissue samples were collected and subjected to HE staining to observe the histocompatibity of the hydrogel.The primary cardiomyocytes isolated from 1-day-old SD rats were used to establish an oxidative stress injury model.The primary cardiomyocyties were divided into control,H2O2 and H2O2+Hydrogel groups.The primary cardiomyocytes in control group were cultured normally,the primary cardiomyocytes in H2O2 group were treated with 200 μmol·L-1 H2O2 for 24 h,and the primary cardiomyocytes in H2O2+Hydrogel group were incubated with 1 g·L-1 composite hydrogel and 200 μmol·L-1 H2O2 for 24 h.The viabilities of cardiomyocytes in various groups were assessed by cell counting kit-8(CCK-8)method.Dihydroethidium(DHE)and 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA)staining were used to assess the reactive oxygen species(ROS)levels in the cells.The expressions of filamentous actin(F-actin)in the cells in various groups were detected by phalloidin fluorescence staining;the expressions of connexin 43(Cx43)and cardiac troponin T(cTnT)proteins in the cardiomyocytes in various groups were detected by immunofluorescence method.The apoptotic rates of cardiomyocytes in various groups were assessed with TUNEL staining method.The expression levels of apoptosis-related proteins B-cell lymphoma-2(Bcl-2)and Bcl-2-associated X protein(Bax)in the cardiomyocytes in various groups were assessed by Western blotting method.Results:The HE staining results showed that the inflammatory cells around the implanted hydrogel were less infiltrated,and the inflammatory reaction of subcutaneous implantation was less.Compared with control group,the viability of cardiomyocytes in H2O2 group was significantly decreased(P＜0.05),the level of ROS in the cells was increased(P＜0.05),the expression levels of Cx43,cTnT and F-actin proteins in the cells were decreased(P＜0.001),the apoptosis rate of cardiomyocytes were decreased(P＜0.01),the expression level of Bcl-2 protein in the cells was increased(P＜0.001),and the expression level of Bax protein was decreased(P＜0.01).Compared with H2O2 group,the viability of cardiomyocytes was significantly increased(P＜0.05),the level of ROS in the cells was decreased(P＜0.01),the expression levels of cTnT,Cx43 and F-actin proteins were increased(P＜0.01),the apoptotic rate of cardiomyocytes were significantly decreased(P＜0.001),the expression level of Bcl-2 protein in the cells were decreased(P＜0.01),and the expression level of Bax protein was increased(P＜0.01).Conclusion:Hydrogel may promote the expression of cardiomyocyte-related proteins by scavenging ROS in the environment and inhibit the cardiomyocyte apoptosis to achieve the protective effect on the cardiomyocytes under oxidative stress.

Objective To explore the current status of medical technology anxiety experienced by elder-ly patients during the use of digital healthcare technology and its influencing factors.Methods A convenience sampling method was used to select 552 elderly patients from 10 hospitals in Liaoning Province as study sub-jects.A cross-sectional survey was conducted using the technology anxiety scale,ehealth literacy scale,self-ef-ficacy scale,and family APGAR index.Results The smart healthcare medical technology anxiety scale score for older patients was(44.93±14.30)points,and the ehealth literacy scale score was(25.29±9.61)points.Smart healthcare medical technology anxiety in older patients was negatively correlated with ehealth literacy,self-efficacy,and family care index(r=-0.299,-0.336,-0.304,P<0.01).Multiple linear regression showed that age,education level,living situation,monthly income,household registration,presence of chronic disease,ehealth literacy,self-efficacy,and family care index were influencing factors for smart healthcare medi-cal technology anxiety in older patients(P<0.05),collectively explaining 35.8%of the variance.Conclusion Ol-der patients exhibit a moderate-to-high level of smart healthcare medical technology anxiety,while their ehealth litera-cy remains at a low level.

Objective:To investigate the influence of genetic and environmental factors on the clinical characteristics of upper urinary tract calculi in pediatric patients.Methods:This study was a retrospective case series. The clinical data of 179 children under the age of 14 with upper urinary tract calculi treated at Beijing Friendship Hospital，Capital Medical University，from August 2014 to February 2023 were analyzed. There were 121 males（67.60%）and 58 females（32.40%），with a median age at onset of 2.10（1.14，5.17）years. Thirty-three cases（18.44%）had a family history of urinary stone disease. Stone characteristics was defined by CT，with a median stone burden（sum of the diameters of all stones）of 1.3（1.00，1.60）cm. Fifty-four（30.17%）children had staghorn calculi. Multiple stones were present in 92 cases（51.40%），and bilateral stones in 52 cases（29.05%），with hydronephrosis was present in 119 children（66.48%）. The median follow-up time was 67 months，and 36 children（20.11%）experienced stone recurrence. Dietary habits and related information were collected by electronic questionnaire，including a total of 115 children（64.25%）with an unbalanced diet，101（56.42%）with insufficient water intake，and 32 children（17.88%）with a preference for a high-protein diet. Tap water was used as the source of drinking water by 128 patients（71.51%），and 107（59.78%）took dietary supplements. Whole-exome sequencing revealed that 55 children（30.73%）carried pathogenic mutations in stone-related genes. Binary logistic regression was used for univariate analysis of above risk factors. Variables with P < 0.1 in univariate analysis and without multicollinearity were included in multivariate logistic regression to further screen for independent risk factors. Results:Multivariate analysis confirmed that carrying stone-related pathogenic gene mutations（ OR = 3.06，95% CI 1.25?7.45， P = 0.014）and insufficient water intake（ OR = 3.28，95% CI 1.14?9.47， P = 0.028）were independent risk factors for higher stone burden. A high-protein diet（ OR = 2.40，95% CI 1.03?5.63， P = 0.044），carrying stone-related pathogenic gene mutations（ OR = 4.57，95% CI 2.21?9.46， P<0.01），and a family history of stones（ OR = 3.18，95% CI 1.28 ~ 7.91， P = 0.013）were independent risk factors for staghorn calculi. Multiple stones were closely associated with a family history of stones（ OR = 2.66，95% CI 1.15-6.17， P = 0.022）and carrying stone-related pathogenic gene mutations（ OR = 3.22，95% CI 1.60-6.48， P = 0.001）. Moreover，carrying stone-related pathogenic gene mutations（ OR = 5.19，95% CI 2.52?13.82， P < 0.01）were an independent risk factor for stone recurrence，whereas dietary supplement intake was a protective factor（ OR = 0.26，95% CI 0.11?0.62， P = 0.002）. Conclusions:Genetic and environmental factors play significant roles in the occurrence and development of pediatric upper urinary tract stones. A high-protein diet as well as a positive family history of stones are independent risk factors for staghorn calculi，and insufficient water intake is a critical environmental factor for stone formation，while appropriate use of dietary supplements may help reduce the risk of stone recurrence. Genetic testing indicates that approximately 30% of children carry stone-related pathogenic gene mutations，and these patients prone to severe stone and an increased risk of recurrence.