ObjectiveTo investigate the mechanism of modified Si Junzitang and Shashen Maidong Tang ［Yiqi Yangyin Jiedu prescription （YQYYJD）］ in enhancing the sensitivity of cisplatin in epidermal growth factor receptor tyrosine kinase inhibitor （EGFR-TKI）-resistant lung adenocarcinoma cells based on aerobic glycolysis. MethodsThe effects of different concentrations of YQYYJD （0， 2， 3， 4， 5， 6， 7， 8 g·L^-1） and cisplatin （0， 3， 6， 9， 12， 15， 18， 21， 24， 27 mg·L^-1） on the proliferation and activity of PC9/GR cells were detected by the cell counting kit-8 （CCK-8） assay after 24 hours of intervention. The half-maximal inhibitory concentration （IC₅₀） for PC9/GR cells was calculated to determine the concentrations used in subsequent experiments. PC9/GR cells were divided into blank group （complete medium）， YQYYJD group （5 g·L^-1）， cisplatin group （12 mg·L^-1）， and combined group （YQYYJD 5 g·L^-1 + cisplatin 12 mg·L^-1）. After 24 hours of intervention， cell viability was measured using CCK-8 assay. Cell proliferation was assessed by colony formation assay， and cell migration was evaluated by scratch and Transwell assays. Glucose consumption， lactate production， and adenosine triphosphate （ATP） levels were measured by colorimetric assays. The expression levels of glycolysis-related proteins， including hexokinase 2 （HK2）， phosphofructokinase P （PFKP）， pyruvate kinase M2 （PKM2）， lactate dehydrogenase A （LDHA）， glucose transporter 1 （GLUT1）， and monocarboxylate transporter 4 （MCT4）， were determined by Western blot. ResultsBoth YQYYJD and cisplatin inhibited the viability of PC9/GR cells in a concentration-dependent manner. The IC₅₀ of PC9/GR cells for YQYYJD and cisplatin were 5.15 g·L^-1 and 12.91 mg·L^-1， respectively. In terms of cell proliferation， compared with the blank group， the cell survival rate and the number of colonies formed in the YQYYJD group， cisplatin group， and combined group were significantly decreased （P<0.01）. Compared with the YQYYJD and cisplatin groups， the combined group showed a further significant reduction in cell survival rate and colony formation （P<0.01）. In terms of cell migration， compared with the blank group， the cell migration rate and the number of cells passing through the Transwell membrane in the YQYYJD group， cisplatin group， and combined group were significantly decreased （P<0.01）. Compared with the YQYYJD and cisplatin groups， the combined group exhibited a further significant reduction in cell migration rate and the number of cells passing through the Transwell membrane （P<0.01）. In terms of glycolysis， compared with the blank group， glucose consumption， lactate production， and ATP levels in the YQYYJD group， cisplatin group， and combined group were significantly decreased （P<0.01）. Compared with the YQYYJD and cisplatin groups， the combined group showed a further significant reduction in glucose consumption， lactate production， and ATP levels （P<0.05）. Compared with the blank group， the protein expression levels of HK2， PFKP， PKM2， and LDHA in the YQYYJD， cisplatin， and combined groups were significantly decreased （P<0.01）. The combined group showed a further significant reduction in the expression levels of these proteins compared with the YQYYJD and cisplatin groups （P<0.01）. No significant differences were observed in the protein expression levels of GLUT1 and MCT4 among the groups. ConclusionYQYYJD can synergistically inhibit the proliferation and migration of PC9/GR cells and enhance their sensitivity to cisplatin. The mechanism may be related to the downregulation of the expression of glycolysis-related rate-limiting enzymes， including HK2， PFKP， PKM2， and LDHA， thereby inhibiting glycolysis.

ObjectiveTo establish a model that can quickly identify the aroma components in different parts of Nardostachys jatamansi， so as to provide a quality control basis for the market circulation and clinical use of N. jatamansi. MethodsHeadspace solid-phase microextraction-gas chromatography-mass spectrometry（HS-SPME-GC-MS） combined with Smart aroma database and National Institute of Standards and Technology（NIST） database were used to characterize the aroma components in different parts of N. jatamansi， and the aroma components were quantified according to relative response factor（RRF） and three internal standards， and the markers of aroma differences in different parts of N. jatamansi were identified by orthogonal partial least squares-discriminant analysis（OPLS-DA） and cluster thermal analysis based on variable importance in the projection（VIP） value >1 and P<0.01. The odor data of different parts of N. jatamansi were collected by Heracles Ⅱ Neo ultra-fast gas phase electronic nose， and the correlation between compound types of aroma components collected by the ultra-fast gas phase electronic nose and the detection results of HS-SPME-GC-MS was investigated by drawing odor fingerprints and odor response radargrams. Chromatographic peak information with distinguishing ability≥0.700 and peak area≥200 was selected as sensor data， and the rapid identification model of different parts of N. jatamansi was established by principal component analysis（PCA）， discriminant factor alysis（DFA）， soft independent modeling of class analogies（SIMCA） and statistical quality control analysis（SQCA）. ResultsThe HS-SPME-GC-MS results showed that there were 28 common components in the underground and aboveground parts of N. jatamansi， of which 22 could be quantified and 12 significantly different components were screened out. Among these 12 components， the contents of five components（ethyl isovalerate， 2-pentylfuran， benzyl alcohol， nonanal and glacial acetic acid，） in the aboveground part of N. jatamansi were significantly higher than those in the underground part（P<0.01）， the contents of β-ionone， patchouli alcohol， α-caryophyllene， linalyl butyrate， valencene， 1，8-cineole and p-cymene in the underground part of N. jatamansi were significantly higher than those in the aboveground part（P<0.01）. Heracles Ⅱ Neo electronic nose results showed that the PCA discrimination index of the underground and aboveground parts of N. jatamansi was 82， and the contribution rates of the principal component factors were 99.94% and 99.89% when 2 and 3 principal components were extracted， respectively. The contribution rate of the discriminant factor 1 of the DFA model constructed on the basis of PCA was 100%， the validation score of the SIMCA model for discrimination of the two parts was 99， and SQCA could clearly distinguish different parts of N. jatamansi. ConclusionHS-SPME-GC-MS can clarify the differential markers of underground and aboveground parts of N. jatamansi. The four analytical models provided by Heracles Ⅱ Neo electronic nose（PCA， DFA， SIMCA and SQCA） can realize the rapid identification of different parts of N. jatamansi. Combining the two results， it is speculated that terpenes and carboxylic acids may be the main factors contributing to the difference in aroma between the underground and aboveground parts of N. jatamansi.

ObjectiveTo investigate the mechanism of ferroptosis mediated by long-chain acyl-CoA synthetase 4 （ACSL4） signalling pathway in rats with coronary heart disease with blood stasis syndrome and the intervention effect of Xuefu Zhuyutang. MethodsSPF male SD rats were randomly divided into normal group， sham-operation group， model group， trimetazidine group （5.4 mg·kg^-1）， low-， medium-， and high-dose group （3.51， 7.02，14.04 g·kg^-1） of Xuefu Zhuyutang. The coronary artery left anterior descending ligation method was used to prepare a model of coronary heart disease with blood stasis syndrome， and continuous treatment for 7 d was conducted， while the sham-operation group was only threaded and not ligated. The general macroscopic symptoms of the rats were observed， and indicators such as electrocardiogram， echocardiography， and blood rheology were detected. The pathological morphology of myocardial tissue was observed by hematoxylin-eosin （HE） staining， and the changes in mitochondria in myocardial tissue were observed by transmission electron microscopy. The level of iron deposition in myocardial tissue was observed by Prussian blue staining. The levels of 12-hydroxyeicosatetraenoic acid （12-HETE） and 15-HETE were detected in serum by enzyme-linked immunosorbent assay. A biochemical colourimetric assay was used to detect the levels of Fe²⁺， lipid peroxidation （LPO）， glutathione （GSH）， and T-GSH/glutathione disulfide （GSSG） in myocardial tissue. DCFH-DA fluorescence quantitative assay was employed to detect the levels of reactive oxygen species （ROS）. Western blot and Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was adopted to detect the protein and mRNA expressions of glutathione peroxidase 4 （GPX4）， ferritin heavy chain 1 （FTH1）， ACSL4， and ly-sophosphatidylcholine acyltransferase3 （LPCAT3） in myocardial tissue. ResultsCompared with those in the normal group， the rats in the model group were poor in general macroscopic symptoms. The electrocardiogram showed widened QRS wave amplitude and increased voltage， bow-back elevation of the ST segments， elevated T waves， J-point elevation， and accelerated heart rate. Echocardiography showed a significant reduction in left ventricular ejection fraction （LVEF） and left ventricular fraction shortening （LVFS） （P<0.01）. Blood rheology showed that the viscosity of the whole blood （low， medium， and high rate of shear） was significantly increased （P<0.01）. HE staining showed an abnormal structure of myocardial tissue. There was a large area of myocardial necrosis and inflammatory cell infiltration and a large number of connective tissue between myocardial fibers. Transmission electron microscopy showed that the mitochondria were severely atrophy or swelling. The cristae were reduced or even broken， and the matrix was flocculent or even vacuolated. Prussian blue staining showed that there were a large number of iron-containing particles， and the iron deposition was obvious. The content of 12-HETE and 15-HETE in the serum was significantly increased （P<0.01）. The content of Fe²⁺， LPO， and ROS in myocardial tissue was significantly increased （P<0.01）. The content of GSH was significantly decreased （P<0.01）， and T-GSH/GSSG was decreased （P<0.01）. The protein and mRNA expressions of GPX4 and FTH1 in myocardial tissue were both significantly decreased （P<0.05， P<0.01）， while those of ACSL4 and LPCAT3 increased significantly （P<0.01）. Compared with the model group， the general macroscopic symptoms and electrocardiogram results of rats in low-， medium- and high-dose groups of Xuefu Zhuyutang were alleviated， and the differences in LVEF/LVFS ratios were all significantly increased （P<0.05， P<0.01）. The differences in whole-blood viscosity （low， medium， and high rate of shear） were all significantly decreased （P<0.01）. The results of HE staining and transmission electron microscopy showed that the morphology， structure， and mitochondria of cardiomyocytes were improved. The content of 12-HETE and 15-HETE in serum was reduced to different degrees in low-， medium-， and high-dose groups of Xuefu Zhuyutang （P<0.05， P<0.01）. The content of Fe²⁺， LPO， and ROS was significantly reduced in the medium- and high-dose groups of Xuefu Zhuyutang （P<0.05， P<0.01）， and the content of GSH and T-GSH/GSSG was significantly increased （P<0.05， P<0.01）. The protein and mRNA expressions of GPX4 and FTH1 were significantly increased to varying degrees in the medium- and high-dose groups of Xuefu Zhuyutang （P<0.05， P<0.01）， and ACSL4 and LPCAT3 were decreased to different degrees in the low-， medium-， and high-dose groups of Xuefu Zhuyutang （P<0.05， P<0.01）. ConclusionXuefu Zhuyutang can regulate iron metabolism and anti-lipid oxidation reaction to mediate ferroptosis through the ACSL4 signalling pathway， thus exerting a protective effect on rats with coronary heart disease with blood stasis syndrome.

Jiegengtang is a basic formula for treating sore throat and cough. By means of bibliometrics， this study conducted a textual research and analysis on the key information such as formula origin， decocting methods， and clinical application of Jiegengtang. After the research， it can be seen that Jiegengtang is firstly contained in Treatise on Febrile and Miscellaneous Disease， which is also known as Ganjietang， and it has been inherited and innovated by medical practitioners of various dynasties in later times. The origins of Chinese medicines in this formula is basically clear， Jiegeng is the dried roots of Platycodon grandiflorum， Gancao is the dried roots and rhizomes of Glycyrrhiza uralensis， the two medicines are selected raw products. The dosage is 27.60 g of Glycyrrhizae Radix et Rhizoma and 13.80 g of Platycodonis Radix， decocted with 600 mL of water to 200 mL， taken warmly after meals， twice a day， 100 mL for each time. In ancient times， Jiegengtang was mainly used for treating Shaoyin-heat invasion syndrome， with cough and sore throat as its core symptoms. In modern clinical practice， Jiegengtang is mainly used for respiratory diseases such as pharyngitis， esophagitis， tonsillitis and lung abscess， especially for pharyngitis and lung abscess with remarkable efficacy. This paper can provide literature reference basis for the modern clinical application and new drug development of Jiegengtang.

Jiegengtang is a basic formula for treating sore throat and cough. By means of bibliometrics， this study conducted a textual research and analysis on the key information such as formula origin， decocting methods， and clinical application of Jiegengtang. After the research， it can be seen that Jiegengtang is firstly contained in Treatise on Febrile and Miscellaneous Disease， which is also known as Ganjietang， and it has been inherited and innovated by medical practitioners of various dynasties in later times. The origins of Chinese medicines in this formula is basically clear， Jiegeng is the dried roots of Platycodon grandiflorum， Gancao is the dried roots and rhizomes of Glycyrrhiza uralensis， the two medicines are selected raw products. The dosage is 27.60 g of Glycyrrhizae Radix et Rhizoma and 13.80 g of Platycodonis Radix， decocted with 600 mL of water to 200 mL， taken warmly after meals， twice a day， 100 mL for each time. In ancient times， Jiegengtang was mainly used for treating Shaoyin-heat invasion syndrome， with cough and sore throat as its core symptoms. In modern clinical practice， Jiegengtang is mainly used for respiratory diseases such as pharyngitis， esophagitis， tonsillitis and lung abscess， especially for pharyngitis and lung abscess with remarkable efficacy. This paper can provide literature reference basis for the modern clinical application and new drug development of Jiegengtang.

[Objective] To explore the feasibility of using whole blood as a source of NK cells for allogeneic CAR NK cell therapy and activated NK cell reinfusion therapy, and initially construct a technical system for the separation and purification of NK cells from whole blood. [Methods] All peripheral blood mononuclear cells (PBMCs) were enriched from 400 mL of whole blood by manual separation and machine separation, respectively. The erythrocyte loss rate, PBMCs number, NK cell purity of the two methods were compared. NK cells were sorted from PBMCs by three separation and enrichment methods as immunomagnetic bead negative selection method, platelet lysate culture expansion and PERCOLL density gradient separation method, and the purity and yield of NK cells, the activity of NK cells and the tumor-killing ability of the three separation and enrichment methods were compared. [Results] The proportion of NK cells in the lymphocyte population was higher in the manual separation method than in the machine separation method[(13.16±5.16)% vs (8.56±3.92)%, P<0.05]; the number PBMCs was lower in the manual separation method than in the machine separation method[(4.09±1.80)×10⁸vs (6.49±2.16)×10⁸, P<0.05], and there was no difference in the red blood cell loss between the two methods (P>0.05). The purity of NK cells isolated and enriched from PBMCs by manual separation method using immunomagnetic was (96.77±2.31)%; the yield was (56.27±10.47)%; the inhibition of tumor proliferation was (38.67±14.05)%; and the tumor killing rate was (19.90±8.05)%. The purity of NK cells isolated and enriched from PBMCs by manual separation method using platelet lysis culture expansion method was the highest at day 7, which was (54.84±15.80)%; the cell expansion multiple could reach 16.92±6.28 at day 7; the in vitro tumor killing rate of NK cells was (15.83±5.5)%; the tumor inhibition rate was (44.33±13.5)%; and there was no difference in the toxicity and activity of NK cells between the two methods (P>0.05). The purity of NK cells isolated and enriched by PERCOLL density gradient separation method was (15.83±5.82)%, and the yield was (14±6.25)%, which was significantly lower than the other two methods. [Conclusion] PBMCs isolated from whole blood by manual separation and NK cells enriched by negative selection with immunomagnetic beads have the potential to provide NK cell materials for CAR-NK cell therapy, and NK cells enriched by platelet lysate-conditioned medium have the potential to provide NK cells for large-scale NK cell activation reinfusion therapy.

Objective: To determine the clinical efficacy and mechanism of Piwei Peiyuan Pill (PPP) combined with moxibustion for treating patients with chronic atrophic gastritis (CAG) with spleen and stomach weakness syndrome. Methods: Ninety-six CAG patients with spleen and stomach weakness syndrome who met the inclusion and exclusion criteria were enrolled at the Department of Spleen and Stomach Diseases of the Second Affiliated Hospital of Anhui University of Chinese Medicine from June 2022 to December 2023. The patients were randomly divided into a control, a Chinese medicine, and a combined group using a random number table method, with 32 cases in each group (two cases per group were excluded). The control group was treated with rabeprazole combined with folic acid tablets (both thrice daily), the Chinese medicine group was treated with PPP (8 g, thrice daily), and the combined group was treated with moxa stick moxibustion (once daily) on the basis of the Chinese medicine group for 12 consecutive weeks. Gastric mucosa atrophy in the three groups was observed before and after treatment. The gastric mucosal pathological score was evaluated. The Patient Reported Outcome (PRO) scale was used to evaluate the patients′ physical and mental health status and quality of life.An enzyme-linked immunosorbent assay was used to detect serum tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-4, IL-10, IL-37, and transforming growth factor (TGF)-β levels in each group. Real-time fluorescence PCR was used to detect the relative expression levels of signal transducer and activator of transcription 3 (STAT3) and mammalian target of rapamycin (mTOR) mRNA in each group. Western blotting was used to detect the relative expression levels of proteins related to the STAT3/mTOR signaling pathway, and the adverse drug reactions and events were recorded and compared. Results: There was no statistical difference in age, gender, disease duration, family history of gastrointestinal tumors, alcohol consumption history, and body mass index among the three groups of patients.The total therapeutic efficacy rates of the control, Chinese medicine, and combined groups in treating gastric mucosal atrophy were 66.67% (20/30), 86.67% (26/30), and 90.00% (27/30), respectively (P<0.05). Compared to before treatment, the pathological and PRO scale scores of gastric mucosa in each group decreased after treatment, and TNF-α, IL-1β, IL-37, and TGF-β levels decreased. The relative STAT3 and mTOR mRNA expression levels, as well as the relative STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels decreased (P<0.05), whereas the IL-4 and IL-10 levels increased (P<0.05). After treatment, compared to the control group, the pathological score of gastric mucosa, PRO scale score, TNF-α, IL-1β, IL-37, TGF-β content, relative STAT3 and mTOR mRNA expression levels, and relative STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels in the Chinese medicine and combined groups after treatment were reduced (P<0.05), whereas the IL-4 and IL-10 levels increased (P<0.05). After treatment, compared to the Chinese medicine group, the combined group showed a decrease in relative STAT3, mTOR mRNA expression levels, and STAT3, p-STAT3, mTOR, and p-mTOR protein expression levels (P<0.05). Conclusion The combination of PPP and moxibustion may regulate the inflammatory mechanism of the body by inhibiting the abnormal activation of the STAT3/mTOR signaling pathway, upregulating related anti-inflammatory factor levels, downregulating pro-inflammatory factor expression, and increasing related repair factor expression, thereby promoting the recovery of atrophic gastric mucosa, reducing discomfort symptoms, and improving the physical and mental state of CAG patients with spleen and stomach weakness syndrome.

Isoliquiritigenin (ISL) is a chalcone compound isolated from licorice, known for its anti-diabetic, anti-cancer, and antioxidant properties. Our previous study has demonstrated that ISL effectively lowers blood glucose levels in type 2 diabetes mellitus (T2DM) mice and improves disturbances in glucolipid and energy metabolism induced by T2DM. This study aims to further investigate the effects of ISL on alleviating abnormal endoplasmic reticulum stress (ERS) caused by T2DM and to elucidate its molecular mechanisms. In vivo experiments were conducted using 8-week-old SPF male C57BL/6J mice. The T2DM animal model was established by high-fat and high-sugar diet combined with intraperitoneal injections of streptozotocin (STZ), in compliance with the ethical guidelines set by the Animal Welfare Committee of Beijing University of Chinese Medicine (approval number: BUCM-2022021503-1134). In vitro experiments employed human liver cancer HepG2 cells, which were induced with tunicamycin (TM) to establish the ERS cell model. Transcriptomic sequencing was used to analyze changes in gene expression in the liver samples of T2DM mice following ISL treatment. Real-time quantitative polymerase chain reaction (RT-qPCR) was employed to assess the regulatory effects of ISL on key ERS genes. Enzyme-linked immunosorbent assay (ELISA), Western blot (WB), and immunofluorescence techniques were used to evaluate ISL's effects on ERS-related proteins. Results indicate that ISL significantly downregulates the expression of ERS-related genes, reduces the level of glucose-regulated protein 78 (GRP78), and inhibits the phosphorylation of protein kinase RNA-like endoplasmic reticulum kinase (PERK), thereby alleviating abnormal ERS induced by T2DM. Additionally, ISL increases the protein levels of insulin receptor substrate (IRS) 1 and IRS2 and enhances the phosphorylation of protein kinase B (Akt), thereby improving insulin sensitivity. In conclusion, ISL is able to alleviate T2DM associated symptoms by improving abnormal ERS and enhancing insulin sensitivity.

BACKGROUND:Fibromyalgia syndrome,as a common rheumatic disease,is related to central sensitization and immune abnormalities.However,the specific mechanism has not been elucidated,and there is a lack of specific diagnostic markers.Exploring the possible pathogenesis of this disease has important clinical significance. OBJECTIVE:To screen the potential diagnostic marker genes of fibromyalgia syndrome and analyze the possible immune infiltration characteristics based on bioinformatics methods,such as weighted gene co-expression network analysis(WGCNA),and machine learning. METHODS:Gene expression profiles in peripheral serum of fibromyalgia syndrome patients and healthy controls were obtained from the gene expression omnibus(GEO)database.The differentially co-expressed genes were screened in the expression profile by differential analysis and WGCNA analysis.Least absolute shrinkage and selection operator(LASSO)and support vector machine-recursive feature elimination(SVM-RFE)machine learning algorithm were further used to identify hub biomarkers,and draw receiver operating characteristic curve(ROC)to evaluate the accuracy of diagnosing fibromyalgia syndrome.Finally,single sample gene set enrichment analysis(ssGSEA)and gene set enrichment analysis(GSEA)were used to evaluate the immune cell infiltration and pathway enrichment in patients with fibromyalgia syndrome. RESULTS AND CONCLUSION:Eight down-regulated differentially expressed genes(DEGs)were obtained after differential analysis of the GSE67311 dataset according to the conditions of log2|(FC)|>0 and P<0.05.After WGCNA analysis,497 genes were included in the module(MEdarkviolet)with the highest positive correlation(r=0.22,P=0.04),and 19 genes were included in the module(MEsalmon2)with the highest negative correlation(r=-0.41,P=6×10-5).After intersecting DEGs and the module genes of WGCNA,seven genes were obtained.Four genes were screened out by LASSO regression algorithm and five genes were screened out by SVM-RFE machine learning algorithm.After the intersection of the two,three core genes were identified,which were germinal center associated signaling and motility like,integrin beta-8,and carboxypeptidase A3.The areas under the ROC curve of the three core genes were 0.744,0.739,and 0.734,respectively,indicating that they have good diagnostic value and can be used as biomarkers for fibromyalgia syndrome.The results of immune infiltration analysis showed that memory B cells,CD56 bright NK cells,and mast cells were significantly down-regulated in patients with fibromyalgia syndrome compared with the control group(P<0.05),and were significantly positively correlated with the above three biomarkers(P<0.05).The enrichment analysis suggested that there were nine fibromyalgia syndrome enrichment pathways,mainly related to olfactory transduction pathway,neuroactive ligand-receptor interaction,and infection pathway.The above results showed that the occurrence and development of fibromyalgia syndrome are related to the involvement of multiple genes,abnormal immune regulation,and multiple pathways imbalance.However,the interactions between these genes and immune cells,as well as their relationships with various pathways need to be further investigated.

ObjectiveA multiplex amplification system was constructed based on the capillary electrophoresis platform for simultaneous detection of saliva, semen, and vaginal secretions using tissue-specific RNA markers. The aim of this study is to identify the tissue origin of suspicious body fluid stains found at crime scenes and determine whether the body fluid stains at the crime scene are one or several types among saliva, semen, and vaginal secretions. MethodsThirty saliva samples, forty semen samples, and forty vaginal secretion samples (half from 2015 and half from 2024) were collected from healthy adult volunteers. Through primer designing, system formulation, and PCR condition optimization, a multiplex fluorescent amplification system was constructed. The specificity, sensitivity, and detection ability for mixed samples of this system were investigated, and it was tested using real crime scene materials. In the primer design stage, to reduce the requirements for RNA template quality, the amplification products were set within 80-300 bp. In the system formulation stage, dominant and subordinate primers were mainly considered. By reducing the concentration of dominant primers and increasing that of subordinate primers, a capillary electrophoresis spectrum with an appropriate peak height ratio was finally obtained. Additionally, gradient experiments were designed to adjust the concentrations of PCR reagents and PCR amplification conditions, and multiple versions of DNA amplification enzymes were optimized to achieve the best experimental results. ResultsThrough statistical analysis, there was no significant difference in the capillary electrophoresis of the 3 types of body fluid samples from the two years (2015 and 2024), demonstrating that the sample preservation method in this study can preserve samples for a relatively long time. The composite amplification system constructed in this study exhibited high specificity for all 3 types of body fluid, with no cross-reactions between the markers of each type of body fluid. The minimum detection thresholds for the 3 types of body fluid reached 0.002 9, 0.001 5, and 0.42 mg/L, respectively. This system also had a high degree of discrimination for mixed samples, especially for semen-saliva mixtures, where each body fluid marker could still be successfully detected when the concentration ratio of semen to saliva was 100:1. Meanwhile, in the two actual cases presented in this article, the application of this composite amplification system performed outstandingly. ConclusionThe composite amplification detection system constructed in this study can achieve the correct screening of saliva, semen, and vaginal secretions, overcoming the problems such as low specificity and sensitivity of marker tests and unbalanced RFU values of each marker in previous studies. The specificity and sensitivity meet the practical work requirements, and the operation is simple. It provides an analytical and identification method for body fluid stains in actual case and is applicable to the identification of the tissue origin of biological evidence at crime scenes involving sexual assault, indecent assault, and other criminal acts. In the future, more types of body fluid markers will be screened to expand the types of body fluids detected by the system, and body fluid-specific cSNP and cInDel genetic markers will be introduced to infer the sources (individuals and types) of mixed and complex stains more accurately.