1.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
2.Stimulation mechanism of osteoblast proliferation and differentiation by Duzhong Decoction-containing serum through L-VGCCs.
Ze-Bin CHEN ; Lan-Lan LUO ; Xin-Yi SHI ; Rui-Tong ZHAO ; Cai-Xian HU ; Yun-Ying FU ; Su-Zhen CHAO ; Bo LIU
China Journal of Chinese Materia Medica 2025;50(12):3335-3345
This paper aimed to explore the effects of Duzhong Decoction(DZD)-containing serum on the proliferation and osteoblast differentiation of MC3T3-E1 cells through L-type voltage-gated calcium channels(L-VGCCs). L-VGCCs inhibitors, nifedipine and verapamil, were used to block L-VGCCs in osteoblasts. MC3T3-E1 cells were divided into a control group, a low-dose DZD-containing serum(L-DZD) group, a medium-dose DZD-containing serum(M-DZD) group, a high-dose DZD-containing serum(H-DZD) group, a nifedipine group, a H-DZD + nifedipine group, verapamil group, and a H-DZD + verapamil group. The CCK-8 method was used for cell proliferation analysis, alkaline phosphatase(ALP) assay kits for intracellular ALP activity measurement, Western blot for protein expression level in cells, real-time fluorescence quantitative PCR technology for intracellular mRNA expression level determination, fluorescence spectrophotometer for free Ca~(2+) concentration determination in osteoblasts, and alizarin red staining(ARS) for mineralized nodule formation in osteoblasts. The experimental results show that compared to the control group, DZD groups can promote MC3T3-E1 cell proliferation, ALP activity, and mineralized nodule formation, increase intracellular Ca~(2+) concentrations, and upregulate the protein expression of bone morphogenetic protein 2(BMP2), collagen Ⅰ(COL1), α2 subunit protein of L-VGCCs(L-VGCCα2), and the mRNA expression of Runt-related transcription factor 2(RUNX2), and BMP2. After blocking L-VGCCs with nifedipine and verapamil, the intervention effects of DZD-containing serum were inhibited to varying degrees. Both nifedipine and verapamil could inhibit ALP activity, reduce mineralized nodule areas, and downregulate the expression of bone formation-related proteins. Moreover, the effects of DZD-containing serum on increasing MC3T3-E1 cell proliferation, osteoblast differentiation, and Ca~(2+) concentrations, upregulating the mRNA expression of osteoprotegerin(OPG) and protein expression of phosphorylated protein kinase B(p-Akt) and phosphorylated forkhead box protein O1(p-FOXO1), and upregulating phosphatase and tensin homolog(PTEN) expression were reversed by nifedipine. The results indicate that DZD-containing serum can increase the Ca~(2+) concentration in MC3T3-E1 cells to promote bone formation, which may be mediated by L-VGCCs and the PTEN/Akt/FoxO1 signaling pathway, providing a new perspective on the mechanism of DZD in treating osteoporosis.
Animals
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Osteoblasts/metabolism*
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Cell Proliferation/drug effects*
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Cell Differentiation/drug effects*
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Mice
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Drugs, Chinese Herbal/pharmacology*
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Calcium Channels, L-Type/genetics*
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Alkaline Phosphatase/genetics*
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Serum/chemistry*
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Cell Line
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Osteogenesis/drug effects*
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Bone Morphogenetic Protein 2/genetics*
3.Effect and mechanism of Bufei Decoction on improving Klebsiella pneumoniae pneumonia in rats by regulating IL-17 signaling pathway.
Li-Na HUANG ; Zheng-Ying QIU ; Xiang-Yi PAN ; Chen LIU ; Si-Fan LI ; Shao-Guang GE ; Xiong-Wei SHI ; Hao CAO ; Rui-Hua XIN ; Fang-di HU
China Journal of Chinese Materia Medica 2025;50(11):3097-3107
Based on the interleukin-17(IL-17) signaling pathway, this study explores the effect and mechanism of Bufei Decoction on Klebsiella pneumoniae pneumonia in rats. SD rats were randomly divided into the control group, model group, Bufei Decoction low-dose group(6.68 g·kg~(-1)·d~(-1)), Bufei Decoction high-dose group(13.36 g·kg~(-1)·d~(-1)), and dexamethasone group(1.04 mg·kg~(-1)·d~(-1)), with 10 rats in each group. A pneumonia model was established by tracheal drip injection of K. pneumoniae. After successful model establishment, the improvement in lung tissue damage was observed following drug administration. Core targets and signaling pathways were screened using transcriptomics techniques. Real-time fluorescence quantitative polymerase chain reaction was used to detect the mRNA expression of core targets interleukin-6(IL-6), interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and chemokine CXC ligand 6(CXCL6). Western blot was used to assess key proteins in the IL-17 signaling pathway, including interleukin-17A(IL-17A), nuclear transcription factor-κB activator 1(Act1), tumor necrosis factor receptor-associated factor 6(TRAF6), and downstream phosphorylated p38 mitogen-activated protein kinase(p-p38 MAPK), and phosphorylated nuclear factor-κB p65(p-NF-κB p65). Apoptosis of lung tissue cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling(TUNEL). The results showed that, compared with the control group, the model group exhibited significant pathological damage in lung tissue. The mRNA expression of IL-6, IL-1β, TNF-α, and CXCL6, as well as the protein levels of IL-17A, Act1, TRAF6, p-p38 MAPK/p38 MAPK, and p-NF-κB p65/NF-κB p65, were significantly increased, and the number of apoptotic cells was notably higher, indicating successful model establishment. Compared with the model group, both low-and high-dose groups of Bufei Decoction showed reduced pathological damage in lung tissue. The mRNA expression levels of IL-6, IL-1β, TNF-α, and CXCL6, and the protein levels of IL-17A, Act1, TRAF6, p-p38 MAPK/p38 MAPK, and p-NF-κB p65/NF-κB p65, were significantly decreased, with a significant reduction in apoptotic cells in the high-dose group. In conclusion, Bufei Decoction can effectively improve lung tissue damage and reduce inflammation in rats with K. pneumoniae. The mechanism may involve the regulation of the IL-17 signaling pathway and the reduction of apoptosis.
Animals
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Interleukin-17/metabolism*
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Drugs, Chinese Herbal/administration & dosage*
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Rats, Sprague-Dawley
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Signal Transduction/drug effects*
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Rats
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Male
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Klebsiella pneumoniae/physiology*
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Klebsiella Infections/immunology*
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Humans
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Lung/drug effects*
4.Genome-wide investigation of transcription factor footprints and dynamics using cFOOT-seq.
Heng WANG ; Ang WU ; Meng-Chen YANG ; Di ZHOU ; Xiyang CHEN ; Zhifei SHI ; Yiqun ZHANG ; Yu-Xin LIU ; Kai CHEN ; Xiaosong WANG ; Xiao-Fang CHENG ; Baodan HE ; Yutao FU ; Lan KANG ; Yujun HOU ; Kun CHEN ; Shan BIAN ; Juan TANG ; Jianhuang XUE ; Chenfei WANG ; Xiaoyu LIU ; Jiejun SHI ; Shaorong GAO ; Jia-Min ZHANG
Protein & Cell 2025;16(11):932-952
Gene regulation relies on the precise binding of transcription factors (TFs) at regulatory elements, but simultaneously detecting hundreds of TFs on chromatin is challenging. We developed cFOOT-seq, a cytosine deaminase-based TF footprinting assay, for high-resolution, quantitative genome-wide assessment of TF binding in both open and closed chromatin regions, even with small cell numbers. By utilizing the dsDNA deaminase SsdAtox, cFOOT-seq converts accessible cytosines to uracil while preserving genomic integrity, making it compatible with techniques like ATAC-seq for sensitive and cost-effective detection of TF occupancy at the single-molecule and single-cell level. Our approach enables the delineation of TF footprints, quantification of occupancy, and examination of chromatin influences on TF binding. Notably, cFOOT-seq, combined with FootTrack analysis, enables de novo prediction of TF binding sites and tracking of TF occupancy dynamics. We demonstrate its application in capturing cell type-specific TFs, analyzing TF dynamics during reprogramming, and revealing TF dependencies on chromatin remodelers. Overall, cFOOT-seq represents a robust approach for investigating the genome-wide dynamics of TF occupancy and elucidating the cis-regulatory architecture underlying gene regulation.
Transcription Factors/genetics*
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Humans
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Chromatin/genetics*
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Animals
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Binding Sites
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Mice
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DNA Footprinting/methods*
5.Clinical and contrast-enhanced ultrasonographic characteristics of peripheral lung masses in patients infected with human immunodeficiency virus
Lei ZHAO ; Jingjing HUANG ; Xin MA ; Xia SHI ; Dou WU ; Zhi ZHANG ; Fengxiang SONG ; Jianjian LIU
Chinese Journal of Clinical Medicine 2025;32(2):276-282
Objective To evaluate the clinical characteristics of human immunodeficiency virus (HIV) infected patients with peripheral lung masses (PLMs), and to assess the diagnostic utility of contrast-enhanced ultrasound (CEUS) in differentiating benign and malignant PLMs. Methods A retrospective analysis was performed on the clinical data of 69 patients with PLM treated in Shanghai Public Health Clinical Center from January 2020 to December 2023. All patients underwent percutaneous biopsy, and were categorized into benign group (n=36) and malignant group (n=33). 25 patients were HIV-positive and 44 patients were HIV-negative. The clinical features and CEUS parameters in patients were compared across these groups. Results Patients with malignant masses were significantly older than those with benign masses (P<0.05). In the malignant group, HIV-negative patients exhibited significantly larger tumor diameters compared to HIV-positive patients (P<0.05); in the HIV-positive patients, no significant difference in tumor size was observed between benign and malignant masses. 19 patients underwent CEUS. 10 malignant masses, irrespective of HIV status (10 positive and 9 negative), commonly presented with indistinct margins, delayed enhancement, heterogeneous perfusion, and delayed peak enhancement on CEUS. 9 benign masses showed earlier peak enhancement compared to 10 malignant masses (P<0.05); no significant differences were observed in the initiation and washout time of enhancement between benign and malignant masses. In HIV-positive patients, 5 benign masses frequently demonstrated discrepancies between CEUS findings and pathological results. Conclusions The clinical and CEUS characteristics were different between benign and malignant PLMs. However, CEUS shows limited accuracy in distinguishing benign and malignant PLMs, underscoring the need for pathological confirmation.
6.Process Optimization and Health Risk Assessment of Calcined Haematitum Based on QbD Concept
Yue YANG ; Jingwei ZHOU ; Jialiang ZOU ; Guorong MEI ; Yifan SHI ; Lei ZHONG ; Jiaojiao WANG ; Xuelian GAN ; Dewen ZENG ; Xin CHEN ; Lin CHEN ; Hongping CHEN ; Shilin CHEN ; Yuan HU ; Youping LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):187-196
ObjectiveTo investigate the processing technology of calcined Haematitum based on the concept of quality by design(QbD) and to assess its health risk. MethodsTaking whole iron content, Fe2+ dissolution content and looseness as critical quality attributes(CQAs), and calcination temperature, calcination time, spreading thickness and particle size as critical process parameters(CPPs) determined by the failure mode and effect analysis(FMEA), the processing technology of calcined Haematitum was optimized by orthogonal test combined with analytic hierarchy process-criteria importance through intercriteria correlation(AHP-CRITIC) hybrid weighting method. The contents of heavy metals and harmful elements were determined by inductively coupled plasma mass spectrometry, and the health risk assessment was carried out by daily exposure(EXP), target hazard quotient(THQ) and lifetime cancer risk(LCR), and the theoretical value of the maximum limit was deduced. ResultsThe optimal processing technology for calcined Haematitum was calcination at 650 ℃, calcination time of 1 h, particle size of 0.2-0.5 cm, spreading thickness of 1 cm, and vinegar quenching for 1 time[Haematitum-vinegar(10:3)]. The contents of 5 heavy metals and harmful elements in 13 batches of calcined Haematitum were all decreased with reductions of up to 5-fold. The cumulative THQ of 2 batches of samples was>1, while the cumulative THQ of all batches of Haematitum was>1. The LCR of As in 1 batches of Haematitum was 1×10-6-1×10-4, and the LCR of the rest was<1×10-6, and the LCRs of calcined Haematitum were all<1×10-6, indicating that the carcinogenic risk of calcined Haematitum was low, but special attention should still be paid to Haematitum medicinal materials. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg were formulated as 1 014, 25, 17, 27, 7 mg·kg-1. ConclusionThe optimized processing technology of calcined Haematitum is stable and feasible, and the contents of heavy metals and harmful elements are reduced after processing. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg are formulated to provide a scientific basis for the formulation of standards for the limits of harmful elements in Haematitum.
7.Process Optimization and Health Risk Assessment of Calcined Haematitum Based on QbD Concept
Yue YANG ; Jingwei ZHOU ; Jialiang ZOU ; Guorong MEI ; Yifan SHI ; Lei ZHONG ; Jiaojiao WANG ; Xuelian GAN ; Dewen ZENG ; Xin CHEN ; Lin CHEN ; Hongping CHEN ; Shilin CHEN ; Yuan HU ; Youping LIU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):187-196
ObjectiveTo investigate the processing technology of calcined Haematitum based on the concept of quality by design(QbD) and to assess its health risk. MethodsTaking whole iron content, Fe2+ dissolution content and looseness as critical quality attributes(CQAs), and calcination temperature, calcination time, spreading thickness and particle size as critical process parameters(CPPs) determined by the failure mode and effect analysis(FMEA), the processing technology of calcined Haematitum was optimized by orthogonal test combined with analytic hierarchy process-criteria importance through intercriteria correlation(AHP-CRITIC) hybrid weighting method. The contents of heavy metals and harmful elements were determined by inductively coupled plasma mass spectrometry, and the health risk assessment was carried out by daily exposure(EXP), target hazard quotient(THQ) and lifetime cancer risk(LCR), and the theoretical value of the maximum limit was deduced. ResultsThe optimal processing technology for calcined Haematitum was calcination at 650 ℃, calcination time of 1 h, particle size of 0.2-0.5 cm, spreading thickness of 1 cm, and vinegar quenching for 1 time[Haematitum-vinegar(10:3)]. The contents of 5 heavy metals and harmful elements in 13 batches of calcined Haematitum were all decreased with reductions of up to 5-fold. The cumulative THQ of 2 batches of samples was>1, while the cumulative THQ of all batches of Haematitum was>1. The LCR of As in 1 batches of Haematitum was 1×10-6-1×10-4, and the LCR of the rest was<1×10-6, and the LCRs of calcined Haematitum were all<1×10-6, indicating that the carcinogenic risk of calcined Haematitum was low, but special attention should still be paid to Haematitum medicinal materials. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg were formulated as 1 014, 25, 17, 27, 7 mg·kg-1. ConclusionThe optimized processing technology of calcined Haematitum is stable and feasible, and the contents of heavy metals and harmful elements are reduced after processing. Preliminary theoretical values of the maximum limits of Cu, As, Cd, Pb and Hg are formulated to provide a scientific basis for the formulation of standards for the limits of harmful elements in Haematitum.
8.Influence of corneal fluorescein sodium staining on test results of iTrace visual function analyzer
Xin YIN ; Qingyan LIU ; Xiao SHAO ; Min XUE ; Yao LU ; Shuying MA ; Chunsheng SHI
International Eye Science 2025;25(4):680-684
AIM: To investigate the impact of corneal fluorescein sodium(NaF)staining on the examination results of iTrace visual function analyzer(iTrace).METHODS: Prospective cohort study. Totally 100 patients(100 eyes)with ametropia who visited the outpatient department of Anhui Eye Hospital from April to November 2024 were recruited. They were divided into an experimental group and a control group, with 50 patients(50 eyes, and only the right eyes were selected for inclusion)in each group. In the experimental group, corneal staining was performed using fluorescein sodium staining test strips, while in the control group, 1 drop of 0.9% normal saline was instilled into the eyes. The iTrace examination was conducted before the intervention and at 5, 10, and 20 min after the intervention. The total corneal higher-order aberrations, spherical aberration, coma aberration, trefoil aberration, best sphere value(RO value), asphericity factor(Q value), and corneal vertical refractive power difference(IS value)at each time of examination were recorded and compared.RESULTS: There was no statistically significant difference in the baseline levels between the two groups(all P>0.05). Intra-group comparison revealed that the total higher-order aberrations, spherical aberration, coma aberration, and trefoil aberration measured 5 min after NaF staining in the experimental group were significantly increased compared with those before staining(all P<0.05). Inter-group comparison showed that the changes(differences from the baseline)in the total corneal higher-order aberrations, spherical aberration, coma aberration, and trefoil aberration measured by iTrace 5 min after the intervention in the experimental group were significantly greater than those in the control group(all P<0.05). There was no statistically significant difference in the changes(differences from the baseline)of various iTrace parameters measured at 10 and 20 min after the intervention between the two groups(all P>0.05). There was no statistical significance in the RO value, Q value, and IS value in the two groups(all P>0.05).CONCLUSION: Corneal NaF staining can cause a short-term increase in the wavefront aberration values(total corneal higher-order aberrations, spherical aberration, coma aberration, trefoil aberration)measured by iTrace, and it gradually disappears with the passage of time. However, it has no impact on the measurement of corneal topography parameters(RO value, Q value, IS value).
9.Mechanism of Mingshi Prescription in Regulating Opn4-dopamine Axis to Inhibit Endoplasmic Reticulum Stress and Delay Myopia Progression
Baohua LI ; Zefeng KANG ; Lulu WANG ; Xin YAN ; Jianquan WANG ; Xinyue HOU ; Bobiao NING ; Shanshan YE ; Mengyu LIU ; Yipeng SHI ; Danyu LI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(18):58-67
ObjectiveTo investigate the mechanism by which Mingshi prescription regulates the retinal melanopsin-dopamine (Opn4-DA) axis in myopic mice to inhibit endoplasmic reticulum (ER) stress in the retina and sclera, thereby delaying axial elongation associated with myopia. MethodsSixty 4-week-old male SPF-grade C57BL/6J mice were randomly divided into a normal group, a form-deprived myopia group (FDM group), an intrinsically photosensitive retinal ganglion cells ablation group (ipRGCs group), a Mingshi Prescription group (MSF group, 5.2 g·kg-1), and an ipRGCs + MSF group (5.2 g·kg-1). Except for the normal group, all other groups underwent FDM modeling. Additionally, the ipRGCs and ipRGCs + MSF groups received retinal ipRGC ablation. Three weeks after modeling, the MSF and ipRGCs + MSF groups were administered Mingshi prescription via continuous gavage for six weeks. After refraction and axial length were measured in all mice, eyeballs were collected along with retinal and scleral tissues. Pathological and morphological changes in the retina, choroid, and sclera were observed using periodic acid-Schiff (PAS) staining. Western blot was employed to detect the relative protein expression levels of dopamine D1 receptor (DRD1), C/EBP homologous protein (CHOP), and glucose-regulated protein 78 (GRP78) in the retina, and CHOP and GRP78 in the sclera. Real-time PCR was used to detect the relative mRNA expression of Opn4, CHOP, and GRP78 in the retina, and CHOP and GRP78 in the sclera. Immunofluorescence staining (IF) was performed to detect the expression of Opn4 and DRD1 in retinal tissues. ResultsCompared with the normal group, the FDM group showed a significant myopic shift in refraction (P<0.05) and a significant increase in axial length (P<0.05). The retinal layers were thinner, the number of ganglion cells was reduced, and collagen fibers in the sclera were loosely arranged with evident gaps. Opn4 and DRD1 protein and mRNA expression in the retina were significantly decreased (P<0.05), while CHOP and GRP78 protein and mRNA expression in both retinal and scleral tissues were significantly increased (P<0.05). Compared with the FDM group, the ipRGCs group exhibited further increases in myopic refraction and axial length (P<0.05), more pronounced thinning and looseness in the retinal, choroidal, and scleral layers, lower expression of Opn4 and DRD1 protein and mRNA in the retina (P<0.05), and higher expression of CHOP and GRP78 protein and mRNA in the retina and sclera (P<0.05). Compared with the FDM group, the MSF group showed significantly reduced refractive error and axial length (P<0.05), with improved cellular number, arrangement, and thickness in ocular tissues, increased Opn4 and DRD1 protein and mRNA expression in the retina (P<0.05), and reduced CHOP and GRP78 protein and mRNA expression in both retina and sclera (P<0.05). Similarly, the ipRGCs + MSF group showed significant improvements in terms of the above items compared with the ipRGCs group (P<0.05). ConclusionMingshi Prescription delays myopic axial elongation and refractive progression by regulating the Opn4-DA axis in the retina of myopic mice, thereby inhibiting ER stress in the retina and sclera. This intervention promotes Qi and blood nourishment of the eyes, softens the fascia, and restores ocular rhythm.
10.Analysis of T7 RNA Polymerase: From Structure-function Relationship to dsRNA Challenge and Biotechnological Applications
Wei-Chen NING ; Yu HUA ; Hui-Ling YOU ; Qiu-Shi LI ; Yao WU ; Yun-Long LIU ; Zhen-Xin HU
Progress in Biochemistry and Biophysics 2025;52(9):2280-2294
T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

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