1.Junctophilin-2 MORN-Helix Domain: Structural Basis for Membrane Binding and Hypertrophic Cardiomyopathy-associated Mutations
Jing-Xin WANG ; Zhi-Wei LI ; Wei LIU ; Wen-Qing ZHANG ; Jian-Chao LI
Progress in Biochemistry and Biophysics 2025;52(8):2103-2116
ObjectiveJunctophilin-2 (JPH2) is an essential structural protein that maintains junctional membrane complexes (JMCs) in cardiomyocytes by tethering the plasma membrane to the sarcoplasmic reticulum, thereby facilitating excitation-contraction (E-C) coupling. Mutations in JPH2 have been associated with hypertrophic cardiomyopathy (HCM), but the molecular mechanisms governing its membrane-binding properties and the functional relevance of its membrane occupation and recognition nexus (MORN) repeat motifs remain incompletely understood. This study aimed to elucidate the structural basis of JPH2 membrane association and its implications for HCM pathogenesis. MethodsA recombinant N-terminal fragment of mouse JPH2 (residues1-440), encompassing the MORN repeats and an adjacent helical region, was purified under near-physiological buffer conditions.X-ray crystallography was employed to determine the structure of the JPH2 MORN-Helix domain. Sequence conservation analysis across species and junctophilin isoforms was performed to assess the evolutionary conservation of key structural features. Functional membrane-binding assays were conducted using liposome co-sedimentation and cell-based localization studies in COS7 and HeLa cells. In addition, site-directed mutagenesis targeting positively charged residues and known HCM-associated mutations, including R347C, was used to evaluate their effects on membrane interaction and subcellular localization. ResultsThe crystal structure of the mouse JPH2 MORN-Helix domain was resolved at 2.6 Å, revealing a compact, elongated architecture consisting of multiple tandem MORN motifs arranged in a curved configuration, forming a continuous hydrophobic core stabilized by alternating aromatic residues. A C-terminal α-helix further reinforced structural integrity. Conservation analysis identified the inner groove of the MORN array as a highly conserved surface, suggesting its role as a protein-binding interface. A flexible linker segment enriched in positively charged residues, located adjacent to the MORN motifs, was found to mediate direct electrostatic interactions with negatively charged phospholipid membranes. Functional assays demonstrated that mutation of these basic residues impaired membrane association, while the HCM-linked R347C mutation completely abolished membrane localization in cellular assays, despite preserving the overall MORN-Helix fold in structural modeling. ConclusionThis study provides structural insight into the membrane-binding mechanism of the cardiomyocyte-specific protein JPH2, highlighting the dual roles of its MORN-Helix domain in membrane anchoring and protein interactions. The findings clarify the structural basis for membrane targeting via a positively charged linker and demonstrate that disruption of this interaction—such as that caused by the R347C mutation—likely contributes to HCM pathogenesis. These results not only enhance current understanding of JPH2 function in cardiac E-C coupling but also offer a structural framework for future investigations into the assembly and regulation of JMCs in both physiological and disease contexts.
3.Independent and Interactive Effects of Air Pollutants, Meteorological Factors, and Green Space on Tuberculosis Incidence in Shanghai.
Qi YE ; Jing CHEN ; Ya Ting JI ; Xiao Yu LU ; Jia le DENG ; Nan LI ; Wei WEI ; Ren Jie HOU ; Zhi Yuan LI ; Jian Bang XIANG ; Xu GAO ; Xin SHEN ; Chong Guang YANG
Biomedical and Environmental Sciences 2025;38(7):792-809
OBJECTIVE:
To assess the independent and combined effects of air pollutants, meteorological factors, and greenspace exposure on new tuberculosis (TB) cases.
METHODS:
TB case data from Shanghai (2013-2018) were obtained from the Shanghai Center for Disease Control and Prevention. Environmental data on air pollutants, meteorological variables, and greenspace exposure were obtained from the National Tibetan Plateau Data Center. We employed a distributed-lag nonlinear model to assess the effects of these environmental factors on TB cases.
RESULTS:
Increased TB risk was linked to PM 2.5, PM 10, and rainfall, whereas NO 2, SO 2, and air pressure were associated with a reduced risk. Specifically, the strongest cumulative effects occurred at various lags: PM 2.5 ( RR = 1.166, 95% CI: 1.026-1.325) at 0-19 weeks; PM 10 ( RR = 1.167, 95% CI: 1.028-1.324) at 0-18 weeks; NO 2 ( RR = 0.968, 95% CI: 0.938-0.999) at 0-1 weeks; SO 2 ( RR = 0.945, 95% CI: 0.894-0.999) at 0-2 weeks; air pressure ( RR = 0.604, 95% CI: 0.447-0.816) at 0-8 weeks; and rainfall ( RR = 1.404, 95% CI: 1.076-1.833) at 0-22 weeks. Green space exposure did not significantly impact TB cases. Additionally, low temperatures amplified the effect of PM 2.5 on TB.
CONCLUSION
Exposure to PM 2.5, PM 10, and rainfall increased the risk of TB, highlighting the need to address air pollutants for the prevention of TB in Shanghai.
China/epidemiology*
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Humans
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Air Pollutants/analysis*
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Tuberculosis/epidemiology*
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Incidence
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Meteorological Concepts
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Particulate Matter/adverse effects*
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Environmental Exposure
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Male
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Female
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Adult
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Air Pollution
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Middle Aged
4.Synthesis and Identification of Saturated Arsenic-containing Hydrocarbons
Jia-Jia CHEN ; Ying-Xiong ZHONG ; Xin-Huang KANG ; Chun-Mei DENG ; Bing-Bing SONG ; Xiao-Fei LIU ; Zhuo WANG ; Rui LI ; Jian-Ping CHEN ; Xue-Jing JIA ; Sai-Yi ZHONG
Chinese Journal of Analytical Chemistry 2025;53(3):472-480
Arsenic is a semi-metal,and lipid-soluble arsenic compounds are one of the widespread forms in the environment and food chain,but there is a lack of standards for lipid-soluble arsenic compounds,which is one of the bottlenecks in the current analytical detection and toxicological studies of organic arsenic.In this study,four saturated arsenic-containing hydrocarbons,AsHC 318,AsHC 332,AsHC 346,and AsHC 374(The number is relative molecular mass),were successfully synthesized in three steps by using dimethylarsinic acid,potassium iodide,sodium hydroxide,and four brominated alkanes(1-Bromotetradecane,1-bromopentadecane,1-bromohexadecane,and 1-bromooctadecane)as raw materials.The structures of these four saturated arsenic-containing hydrocarbons were characterized by proton nuclear magnetic resonance(1H NMR)spectroscopy,13C nuclear magnetic resonance(13C NMR)spectroscopy,and high-resolution mass spectrometry(HR-MS).The yields of the method were 8%-10%,and the synthesized compounds could be used in subsequent toxicity evaluation experiments to assess the toxic effects and mechanisms of action of arsenic-containing hydrocarbons.This study provided an effective method for synthesis of arsenic-containing hydrocarbons,enriching the synthesis methods of arsenic-containing hydrocarbons,and provided raw materials for the subsequent toxicological studies of arsenic-containing hydrocarbons.
5.Validation and Forensic Application of a Domestic Human DNA Quantitative De-tection Kit
Jing CHEN ; Ya-Ping WANG ; Yun-Peng FENG ; Xiao-Xin HU ; Zhen-Jun JIA ; Hong-Di LIU ; An-Xin YAN ; Yong-Jiu LI ; Zhu PENG ; Zhi-Fang LIU ; Jian-Gang CHEN
Journal of Forensic Medicine 2025;41(3):252-259
Objective To verify the efficacy of a domestic human DNA quantification kit based on real-time fluorescence quantitative PCR in detecting the total human DNA concentration,male DNA concen-tration in mixed male/female DNA samples,the degree of DNA degradation and inhibitor tolerance.Methods Samples with different concentrations,different male/female ratios,different concentrations of inhibitors,and different degradation degrees were tested using the domestic human DNA quantification kit based on real-time fluorescence quantitative PCR.This kit was compared with a similar product on the market and was applied to the detection of DNA from real cases.Results This human DNA quan-tification kit can effectively detect human DNA as low as 0.001 65 ng/μL,and 6.25 pg/μL of male DNA in mixed samples with a male-to-female ratio of 1∶15 000.Even when the sample contains as high as 400 ng/μL of humic acid or 1 000 μmol/L of hemin alone,the DNA concentration can still be accurately detected.The degradation index can effectively characterize the degradation degree of the sample.This kit has been successfully applied in forensic practice.Conclusion This human DNA quan-tification kit is accurate and reliable in detection.It can accurately reflect the degradation of DNA and inhibitor tolerance.It has good performance in quantitative accuracy,determination of the male/female ratio in mixed samples,and inhibitor tolerance.It has application potential in forensic case examination.
6.Electroacupuncture at Yanglingquan and Quchi Points in Regulates the JAK2/STAT3 Signaling Pathway to Improve the Post-Stroke Spasticity in Rats
Xin HE ; Jian ZHAO ; Wei JING ; Min LIU ; Yuhan LIU ; Peng HAN
Journal of Guangzhou University of Traditional Chinese Medicine 2025;42(2):430-436
Objective To observe the therapeutic effect and mechanism of electroacupuncture at Yanglingquan(GB34)and Quchi(LI11)points for post-stroke spasticity(PSS)in rats.Methods The rats were randomly divided into sham-operated group,model group,electroacupuncture group and electroacupuncture+CA1[Janus kinase 2(JAK2)agonist]group.The PSS model was prepared by the modified middle cerebral artery occlusion combined with internal capsule injection of N-methyl-D-aspartate(NMDA)receptor method in all groups of rats except the sham-operated group.After the intervention,the neurological deficit scale scoring,Ashworth Spasticity Scale(Ashworth)scoring and electrophysiological determination were carried out;the levels of interleukin 6(IL-6),tumor necrosis factor α(TNF-α)and γ-aminobutyric acid(GABA)in the brain tissues were detected by enzyme-linked immunosorbent assay(ELISA);the content of glutamate(Glu)was observed by colorimetry;the pathological changes in brain tissues were observed by hematoxylin-eosin(HE)staining method;the protein expression levels of JAK2,phosphorylated JAK2(p-JAK2),signal transducer and activator of transcription 3(STAT3),and phosphorylated STAT3(p-STAT3)in brain tissues were detected by Western Blot method.Results The neurological deficit scale scores,Ashworth scores,contents of IL-6,TNF-α and Glu as well as p-JAK2/JAK2 and p-STAT3/STAT3 ratios in brain tissues in the model group were all significantly higher than those in the sham-operated group(P<0.05),and the muscular tension signal value and GABA content in brain tissues in the model group were significantly lower than those in the sham-operated group(P<0.05);compared with the model group,the neurological deficit scale scores,Ashworth scores,contents of IL-6,TNF-α and Glu as well as p-JAK2/JAK2 and p-STAT3/STAT3 ratios in brain tissues were significantly lower in the electroacupuncture group(P<0.05),and the muscular tension signal value and GABA content in brain tissues were significantly higher in the electroacupuncture group(P<0.05);compared with the electroacupuncture group,the neurological deficit scale scores,Ashworth scores,contents of IL-6,TNF-α and Glu as well as p-JAK2/JAK2 and p-STAT3/STAT3 ratios in brain tissues in the electroacupuncture+CA1 group were significantly higher(P<0.05),and the muscular tension signal value and GABA content in brain tissues in the electroacupuncture+CA1 group were significantly lower(P<0.05).Conclusion Electroacupuncture may inhibit inflammatory responses and regulate the neuronal excitation/inhibition balance by inhibiting the JAK2/STAT3 pathway,thus relieving PSS in rats.
7.Clinical characteristics of clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia
Huai-Jin XU ; Bing LI ; Kang CHEN ; Hui-Xin ZHOU ; Ya-Jing WANG ; Li ZANG ; Xian-Ling WANG ; Yu CHENG ; Jin DU ; Qing-Hua GUO ; Wei-Jun GU ; Zhao-Hui LYU ; Jian-Ming BA ; Jing-Tao DOU ; Yi-Ming MU
Medical Journal of Chinese People's Liberation Army 2025;50(7):800-807
Objective To investigate the clinical characteristics of patients with clinical and subclinical Cushing's syndrome caused by primary bilateral macronodular adrenal hyperplasia(PBMAH).Methods A retrospective analysis was performed on the clinical data of 198 patients with Cushing's syndrome caused by PBMAH diagnosed in the First Medical Center of Chinese PLA General Hospital from January 2004 to October 2024.According to clinical manifestations,the patients were classified into clinical type Cushing's syndrome(n=61)and subclinical type Cushing's syndrome(n=137),and the clinical characteristics of the two types were compared.Results The mean age at diagnosis of patients with PBMAH-induced Cushing's syndrome was(53.5±10.4)years,including 118 males and 80 females,with a male-to-female ratio of 1.475:1.Compared with the subclinical type,the clinical type had a higher proportion of females,higher levels of serum cortisol,24-hour urine free cortisol(24 h UFC),and inhibited serum cortisol after low-dose dexamethasone suppression.Additionally,the clinical type had lower plasma ACTH,larger adrenal nodules and a higher risk of surgery(P<0.05)compared with those in subclinical type.The incidences of hypertension,dyslipidemia,obesity,diabetes mellitus,hypokalemia,vitamin D deficiency,osteoporosis,coronary heart disease,and cerebrovascular disease in patients with Cushing's syndrome caused by PBMAH were 87.9%,50.5%,37.1%,36.9%,27.8%,25.9%,18.7%,18.7%and 12.1%,respectively.Among them,compared with subclinical type patients,clinical type patients had higher incidence of hypokalaemia,vitamin D deficiency and osteoporosis(P<0.05),while there were no statistically significant differences in the incidences of other comorbidities between the two types(P>0.05).The results of postoperative follow-up for PBMAH patients showed that the short-term biochemical remission rate of unilateral total adrenalectomy was 41.5%(22/53)and the long-term biochemical remission rate was 32.0%(8/25).The short-term biochemical remission rate of unilateral partial(or nodular)adrenalectomy was 52.9%(9/17),and the long-term biochemical remission rate was 14.3%(1/7).All patients who underwent unilateral total adrenalectomy plus contralateral partial resection developed adrenal insufficiency(3/3),and 1 patient(1/3)relapsed 3.4 years after surgery.Conclusion Clinical and subclinical types of Cushing's syndrome caused by PBMAH have their distinct clinical characteristics.Surgery is an effective treatment for PBMAH,but a certain proportion of patients fail to achieve biochemical remission after non-bilateral total adrenalectomy.
8.Effect of annexin A1 mimetic peptide Ac2-26 on the inflammatory response in severe heatstroke mice and its protective mechanisms
Ya-Wen WANG ; Jing-Jing JI ; Jia-Li CUN ; Zhi-Feng LIU ; Xin-Jian ZHANG
Medical Journal of Chinese People's Liberation Army 2025;50(11):1444-1450
Objective To investigate the protective effects of the ANXA1(Annexin A1)mimetic peptide Ac2-26 on mice with severe heatstroke(HS)and its underlying mechanisms.Methods Twenty-four adult healthy male C57BL/6J mice weighing 20-25 g were randomly divided into four groups using a simple random sampling method:control group(Con group),Con+Ac2-26 group,severe heatstroke group(HS group),and severe heatstroke+Ac2-26 group(HS+Ac2-26 group),with 6 mice in each group.Mice in Con+Ac2-26 group and HS+Ac2-26 group were injected intraperitoneally with Ac2-26(6 mg/kg),and the remaining mice of two groups were injected intraperitoneally with normal saline of equivalent volume.One hour after drug administration,mice in HS group and HS+Ac2-26 group were placed in a high-temperature and high-humidity simulated environment[(37.0±0.5)℃,75%±5%humidity],while mice in Con group and Con+Ac2-26 were kept in a room temperature and humidity environment[(24±0.5)℃and 40±5%humidity]throughout the experiment.The anal temperature of the mice was recorded every 5 minutes;when the anal temperature of mice in HS group and HS+Ac2-26 group reached 42℃,they were removed from the high-temperature environment and placed in a room temperature environment for 6 hours of rewarming,after which blood samples of mice in each group were collected.Flow cytometry was used to detect the proportion of neutrophils and the expression levels of Cd11b and Cd62L(molecules related to neutrophil activation).Enzyme-linked immunosorbent assay(ELISA)was used to measure the plasma levels of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6),IL-10,and IL-4.Hematoxylin-eosin staining(HE staining)was performed to observe the pathological changes in lung,kidney and liver tissues.Furthermore,RNA sequencing(RNA-seq)was conducted to detect changes in neutrophil gene expression.Results Compared with Con group,Con+Ac2-26 group showed no significant increase in neutrophil proportion,decreased expression of CD62L and CD11b,no significant changes in cytokine levels,and no obvious pathological changes in lung,kidney,or liver tissues.Compared with HS group,the time for mice in HS+Ac2-26 group to reach an anal temperature of 42℃and the time to develop hypothermia after model establishment were both prolonged(P<0.05);the proportion of neutrophils was reduced(P<0.05);the plasma levels of pro-inflammatory cytokines TNF-α and IL-6 were decreased(P<0.05);and the plasma level of anti-inflammatory cytokine IL-10 was increased(P<0.05).HE staining results showed that compared with HS group,HS+Ac2-26 group had a reduced range of inflammatory cell infiltration in lung,kidney,and liver tissues.RNA-seq results revealed that compared with HS group,HS+Ac2-26 group had decreased expression levels of molecules related to the oxidative phosphorylation signaling pathways and neutrophil extracellular trap(NETs).Conclusion Annexin A1 mimetic peptide Ac2-26 may reduce the pro-inflammatory response and alleviate the heatstroke-induced organ histopathologic damage in heatstroke mice by inhibiting oxidative phosphorylation in heat-stressed cells and NETs formation.
9.Mechanism of Daotan Xixin Decoction in treating APP/PS1 mice based on high-throughput sequencing technology and bioinformatics analysis.
Bo-Lun CHEN ; Jian-Zheng LU ; Xin-Mei ZHOU ; Xiao-Dong WEN ; Yuan-Jing JIANG ; Ning LUO
China Journal of Chinese Materia Medica 2025;50(2):301-313
This study aims to investigate the therapeutic effect and mechanism of Daotan Xixin Decoction on APP/PS1 mice. Twelve APP/PS1 male mice were randomized into four groups: APP/PS1 and low-, medium-, and high-dose Daotan Xixin Decoction. Three C57BL/6 wild-type mice were used as the control group. The learning and memory abilities of mice in each group were examined by the Morris water maze test. The pathological changes of hippocampal nerve cells were observed by hematoxylin-eosin staining and Nissl staining. Immunohistochemistry was employed to detect the expression of β-amyloid(Aβ)_(1-42) in the hippocampal tissue. The high-dose Daotan Xixin Decoction group with significant therapeutic effects and the model group were selected for high-throughput sequencing. The differentially expressed gene(DEG) analysis, Gene Ontology(GO) analysis, Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis, and Gene Set Variation Analysis(GSVA) were performed on the sequencing results. RT-qPCR and Western blot were conducted to determine the mRNA and protein levels, respectively, of some DEGs. Compared with the APP/PS1 group, Daotan Xixin Decoction at different doses significantly improved the learning and memory abilities of APP/PS1 mice, ameliorated the neuropathological damage in the CA1 region of the hippocampus, increased the number of neurons, and decreased the deposition of Aβ_(1-42) in the brain. A total of 1 240 DEGs were screened out, including 634 genes with up-regulated expression and 606 genes with down-regulated expression. The GO analysis predicted the biological processes including RNA splicing and protein folding, the cellular components including spliceosome complexes and nuclear spots, and the molecular functions including unfolded protein binding and heat shock protein binding. The KEGG pathway enrichment analysis revealed the involvement of neurodegenerative disease pathways, amyotrophic lateral sclerosis, and splicing complexes. Further GSVA pathway enrichment analysis showed that the down-regulated pathways involved nuclear factor-κB(NF-κB)-mediated tumor necrosis factor-α(TNF-α) signaling pathway, UV response, and unfolded protein response, while the up-regulated pathways involved the Wnt/β-catenin signaling pathway. The results of RT-qPCR and Western blot showed that compared with the APP/PS1 group, Daotan Xixin Decoction at different doses down-regulated the mRNA and protein levels of signal transducer and activator of transcription 3(STAT3), NF-κB, and interleukin-6(IL-6) in the hippocampus. In conclusion, Daotan Xixin Decoction can improve the learning and memory abilities of APP/PS1 mice by regulating the STAT3/NF-κB/IL-6 signaling pathway.
Animals
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Drugs, Chinese Herbal/administration & dosage*
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Mice
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Male
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Alzheimer Disease/metabolism*
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Computational Biology
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Mice, Inbred C57BL
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High-Throughput Nucleotide Sequencing
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Amyloid beta-Protein Precursor/metabolism*
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Hippocampus/metabolism*
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Mice, Transgenic
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Presenilin-1/metabolism*
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Humans
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Memory/drug effects*
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Maze Learning/drug effects*
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Amyloid beta-Peptides/genetics*
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Disease Models, Animal
10.Processing technology of calcined Magnetitum based on concept of QbD and its XRD characteristic spectra.
De-Wen ZENG ; Jing-Wei ZHOU ; Tian-Xing HE ; Yu-Mei CHEN ; Huan-Huan XU ; Jian FENG ; Yue YANG ; Xin CHEN ; Jia-Liang ZOU ; Lin CHEN ; Hong-Ping CHEN ; Shi-Lin CHEN ; Yuan HU ; You-Ping LIU
China Journal of Chinese Materia Medica 2025;50(9):2391-2403
Guided by the concept of quality by design(QbD), this study optimizes the calcination and quenching process of calcined Magnetitum and establishes the XRD characteristic spectra of calcined Magnetitum, providing a scientific basis for the formulation of quality standards. Based on the processing methods and quality requirements of Magnetitum in the Chinese Pharmacopoeia, the critical process parameters(CPPs) identified were calcination temperature, calcination time, particle size, laying thickness, and the number of vinegar quenching cycles. The critical quality attributes(CQAs) included Fe mass fraction, Fe~(2+) dissolution, and surface color. The weight coefficients were determined by combining Analytic Hierarchy Process(AHP) and the criteria importance though intercrieria correlation(CRITIC) method, and the calcination process was optimized using orthogonal experimentation. Surface color was selected as a CQA, and based on the principle of color value, the surface color of calcined Magnetitum was objectively quantified. The vinegar quenching process was then optimized to determine the best processing conditions. X-ray diffraction(XRD) was used to establish the characteristic spectra of calcined Magnetitum, and methods such as similarity evaluation, cluster analysis, and orthogonal partial least squares-discriminant analysis(OPLS-DA) were used to evaluate the quality of the spectra. The optimized calcined Magnetitum preparation process was found to be calcination at 750 ℃ for 1 h, with a laying thickness of 4 cm, a particle size of 0.4-0.8 cm, and one vinegar quenching cycle(Magnetitum-vinegar ratio 10∶3), which was stable and feasible. The XRD characteristic spectra analysis method, featuring 9 common peaks as fingerprint information, was established. The average correlation coefficient ranged from 0.839 5-0.988 1, and the average angle cosine ranged from 0.914 4 to 0.995 6, indicating good similarity. Cluster analysis results showed that Magnetitum and calcined Magnetitum could be grouped together, with similar compositions. OPLS-DA discriminant analysis identified three key characteristic peaks, with Fe_2O_3 being the distinguishing component between the two. The final optimized processing method is stable and feasible, and the XRD characteristic spectra of calcined Magnetitum was initially established, providing a reference for subsequent quality control and the formulation of quality standards for calcined Magnetitum.
X-Ray Diffraction/methods*
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Drugs, Chinese Herbal/chemistry*
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Quality Control
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Particle Size

Result Analysis
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