1.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
2.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
3.Pharmacoeconomic evaluation of durvalumab combined with chemotherapy as first-line therapy for advanced biliary tract cancer
Liman HUO ; Yangyang DUAN ; Ping LIANG ; Bin SHAN ; Xiaoli SUN ; Rui FENG
China Pharmacy 2025;36(17):2141-2147
OBJECTIVE To assess the cost-effectiveness of durvalumab combined with chemotherapy as a first-line treatment for advanced biliary tract cancer from the perspective of the Chinese healthcare system. METHODS Using data from the TOPAZ-1 clinical trial, a three-state Markov model comprising progression-free survival (PFS), progressive disease (PD) and death was developed, with a cycle length of 21 days and a 10-year time horizon. Patients in the observation group received durvalumab in combination with gemcitabine and cisplatin, whereas those in the control group received placebo plus the same chemotherapy regimen. The evaluation indexes were quality-adjusted life year (QALY) and the incremental cost-effectiveness ratio (ICER). The willingness-to-pay (WTP) threshold was set at three times the 2024 Chinese per capita gross domestic product (GDP) (287 247 yuan/QALY). The sensitivity analyses, along with scenario analyses, were performed. RESULTS In the base-case analysis, the ICER of observation group compared to control group was 1 166 344.46 yuan/QALY, far exceeding the WTP threshold, indicating that the regimen was not cost-effective. One-way sensitivity analysis identified the PD state utility, discount rate, cost of durvalumab, and PFS state utility as the main drivers of ICER variation. Probabilistic sensitivity analysis showed that, at the above WTP threshold, the probability of the acceeptance of this regimen was 0, further supporting the robustness of the base-case findings. In the scenario analysis, inclusion of a patient assistance program reduced the ICER to 235 885.16 yuan/ QALY, below the above WTP threshold, suggesting cost-effectiveness under this assistance program. However, when applying a regional WTP threshold set at three times the per capita GDP (158 475 yuan/QALY) of Gansu Province (the province with the lowest GDP in China in 2024), the ICER remained above the threshold, indicating that the regimen was not cost-effective at the regional level. CONCLUSIONS At current pricing, durvalumab plus chemotherapy as a first-line treatment for advanced biliary tract cancer is not cost-effective in China. Although the introduction of a patient assistance program can substantially reduce the ICER and achieve cost-effectiveness at a WTP threshold set at three times the 2024 per capita GDP of China, due to limited affordability in low-income areas, the program remains not cost-effective.
4.Effect and mechanism of Xintong Granules in ameliorating myocardial ischemia-reperfusion injury in rats by regulating gut microbiota.
Yun-Jia WANG ; Ji-Dong ZHOU ; Qiu-Yu SU ; Jing-Chun YAO ; Rui-Qiang SU ; Guo-Fei QIN ; Gui-Min ZHANG ; Hong-Bao LIANG ; Shuai FENG ; Jia-Cheng ZHANG
China Journal of Chinese Materia Medica 2025;50(14):4003-4014
This study investigates the mechanism by which Xintong Granules improve myocardial ischemia-reperfusion injury(MIRI) through the regulation of gut microbiota and their metabolites, specifically short-chain fatty acids(SCFAs). Rats were randomly divided based on body weight into the sham operation group, model group, low-dose Xintong Granules group(1.43 g·kg~(-1)·d~(-1)), medium-dose Xintong Granules group(2.86 g·kg~(-1)·d~(-1)), high-dose Xintong Granules group(5.72 g·kg~(-1)·d~(-1)), and metoprolol group(10 mg·kg~(-1)·d~(-1)). After 14 days of pre-administration, the MIRI rat model was established by ligating the left anterior descending coronary artery. The myocardial infarction area was assessed using the 2,3,5-triphenyltetrazolium chloride(TTC) staining method. Apoptosis in tissue cells was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL) assay. Pathological changes in myocardial cells and colonic tissue were observed using hematoxylin-eosin(HE) staining. The levels of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), interleukin-6(IL-6), creatine kinase MB isoenzyme(CK-MB), and cardiac troponin T(cTnT) in rat serum were quantitatively measured using enzyme-linked immunosorbent assay(ELISA) kits. The activities of lactate dehydrogenase(LDH), creatine kinase(CK), and superoxide dismutase(SOD) in myocardial tissue, as well as the level of malondialdehyde(MDA), were determined using colorimetric assays. Gut microbiota composition was analyzed by 16S rDNA sequencing, and fecal SCFAs were quantified using gas chromatography-mass spectrometry(GC-MS). The results show that Xintong Granules significantly reduced the myocardial infarction area, suppressed cardiomyocyte apoptosis, and decreased serum levels of pro-inflammatory cytokines(TNF-α, IL-1β, and IL-6), myocardial injury markers(CK-MB, cTnT, LDH, and CK), and oxidative stress marker MDA. Additionally, Xintong Granules significantly improved intestinal inflammation in MIRI rats, regulated gut microbiota composition and diversity, and increased the levels of SCFAs(acetate, propionate, isobutyrate, etc.). In summary, Xintong Granules effectively alleviate MIRI symptoms. This study preliminarily confirms that Xintong Granules exert their inhibitory effects on MIRI by regulating gut microbiota imbalance and increasing SCFA levels.
Animals
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Gastrointestinal Microbiome/drug effects*
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Rats
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Male
;
Myocardial Reperfusion Injury/genetics*
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Drugs, Chinese Herbal/administration & dosage*
;
Rats, Sprague-Dawley
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Apoptosis/drug effects*
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Humans
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Tumor Necrosis Factor-alpha/metabolism*
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Interleukin-6/genetics*
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Malondialdehyde/metabolism*
5.Potential mechanism of Yueju Pills in improving depressive symptoms of psychocardiac diseases based on metabolomics and network pharmacology.
Cheng-Yu DU ; Xue-Feng GUO ; Han-Wen ZHANG ; Jian LIANG ; Huan ZHANG ; Guo-Wei HUANG ; Ping NI ; Hai-Jun MA ; You YU ; Rui YU
China Journal of Chinese Materia Medica 2025;50(16):4564-4573
The therapeutic effects of Yueju Pills on depression and cardiovascular diseases have been widely recognized. Previous studies have shown that the drug can significantly improve depressive-like behaviors induced by chronic unpredictable mild stress(CUMS) combined with atherosclerosis(AS). Given the complex pathogenesis of psychocardiac diseases, this study integrated metabolomics and network pharmacology to systematically elucidate the mechanism of Yueju Pills in alleviating depressive symptoms in psychocardiac diseases. The results demonstrate that, after Yueju Pill intervention, the levels of 9 abnormal metabolites in the hippocampus restore to normal ranges, primarily involving key pathways or signaling pathways, including the cyclic adenosine monophosphate(cAMP), mammalian target of rapamycin(mTOR), glycine/serine/threonine metabolism, and aminoacyl-tRNA biosynthesis. In a high-fat diet-induced CUMS ApoE~(-/-) mouse model, Yueju Pills significantly increases adenosine monophosphate(AMP) levels and decreases L-alanine and D-glyceric acid levels in the hippocampus. In conclusion, Yueju Pills exert antidepressant effects by regulating multiple metabolic axes, including glycine/serine/threonine metabolism and the cAMP, mTOR signaling pathways. Network pharmacology predictions reveal that the treatment of CUMS combined with AS by its core active components may be realized through modulating pathways concerning neuroinflammation and synaptic plasticity, including serine/threonine-protein kinase 1(AKT1), mitogen-activated protein kinase 1(MAPK1), and prostaglandin-endoperoxide synthase 2(PTGS2). This study provides a theoretical reference for the clinical application of Yueju Pills in alleviating the depressive symptoms of psychocardiac diseases.
Animals
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Network Pharmacology
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Mice
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Drugs, Chinese Herbal/administration & dosage*
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Metabolomics
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Male
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Depression/genetics*
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Humans
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Hippocampus/drug effects*
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Mice, Inbred C57BL
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Signal Transduction/drug effects*
6.Correlation of IGF2 levels with sperm quality, inflammation, and DNA damage in infertile patients.
Jing-Gen WU ; Cai-Ping ZHOU ; Wei-Wei GUI ; Zhong-Yan LIANG ; Feng-Bin ZHANG ; Ying-Ge FU ; Rui LI ; Fang WU ; Xi-Hua LIN
Asian Journal of Andrology 2025;27(2):204-210
Insulin-like growth factor 2 (IGF2) is a critical endocrine mediator implicated in male reproductive physiology. To investigate the correlation between IGF2 protein levels and various aspects of male infertility, specifically focusing on sperm quality, inflammation, and DNA damage, a cohort of 320 male participants was recruited from the Women's Hospital, Zhejiang University School of Medicine (Hangzhou, China) between 1 st January 2024 and 1 st March 2024. The relationship between IGF2 protein concentrations and sperm parameters was assessed, and Spearman correlation and linear regression analysis were employed to evaluate the independent associations between IGF2 protein levels and risk factors for infertility. Enzyme-linked immunosorbent assay (ELISA) was used to measure IGF2 protein levels in seminal plasma, alongside markers of inflammation (tumor necrosis factor-alpha [TNF-α] and interleukin-1β [IL-1β]). The relationship between seminal plasma IGF2 protein levels and DNA damage marker phosphorylated histone H2AX (γ-H2AX) was also explored. Our findings reveal that IGF2 protein expression decreased notably in patients with asthenospermia and teratospermia. Correlation analysis revealed nuanced associations between IGF2 protein levels and specific sperm parameters, and low IGF2 protein concentrations correlated with increased inflammation and DNA damage in sperm. The observed correlations between IGF2 protein levels and specific sperm parameters, along with its connection to inflammation and DNA damage, underscore the importance of IGF2 in the broader context of male reproductive health. These findings lay the groundwork for future research and potential therapeutic interventions targeting IGF2-related pathways to enhance male fertility.
Humans
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Male
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Insulin-Like Growth Factor II/metabolism*
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Infertility, Male/genetics*
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DNA Damage
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Adult
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Inflammation/metabolism*
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Spermatozoa/metabolism*
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Semen Analysis
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Semen/metabolism*
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Tumor Necrosis Factor-alpha/metabolism*
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Histones/metabolism*
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Interleukin-1beta/metabolism*
7.mRNA display-enabled discovery of proximity-triggered covalent peptide-drug conjugates.
Ruixuan WANG ; Siqi RAN ; Jiabei GUO ; Da HU ; Xiang FENG ; Jixia ZHOU ; Zhanzhi ZHANG ; Futian LIANG ; Jiamin SHANG ; Lingxin BU ; Kaiyi WANG ; Junyi MAO ; Huixin LUO ; Rui WANG
Acta Pharmaceutica Sinica B 2025;15(10):5474-5485
Peptide-drug conjugates (PDCs) have emerged as a promising modality in precision oncology, enabling targeted delivery of cytotoxic payloads while minimizing off-target toxicity. The integration of covalent warheads, such as those based on sulfur(VI) fluoride exchange (SuFEx) chemistry, enhances drug-target residence time and tumor accumulation. However, existing screening methods for covalent peptide (CP) libraries require post-translational warhead conjugation, limiting throughput. Here, we present an integrated mRNA display platform that incorporates covalent warheads during ribosomal synthesis, enabling efficient screening of ultra-diverse covalent macrocyclic peptide libraries (>1013 variants). This approach, using site-specific incorporation of N-chloroacetyl-d-phenylalanine and fluorosulfate-l-tyrosine, accelerated the discovery of irreversibly binding (K i = 3.58 μmol/L) Nectin-4-targeting peptide CP-N1-N3 via proximity-triggered SuFEx. The peptide was further conjugated to cytotoxic payloads, yielding the covalent PDC CP-N1-MMAE with potent cytotoxicity (IC50 ≈ 43 nmol/L) against MDA-MB-468 cells. This platform establishes a new paradigm for precision covalent drug discovery.
8.The application strategies of non-uniform sampling in the structure elucidation of small molecule compounds—an instantiation using fuziline
Li-li ZHANG ; Ke ZHANG ; Jie LIU ; Chun-wang MENG ; Rui FENG ; Liang XIONG
Acta Pharmaceutica Sinica 2025;60(1):218-224
Two-dimensional nuclear magnetic resonance (2D NMR) is a widely used technique for structural analysis of small molecular compounds. It can obtain information about the hydrogen-hydrogen correlation, hydrogen-carbon single bond correlation, hydrogen-carbon remote correlation, and hydrogen-hydrogen spatial arrangement of compounds. Thus, 2D NMR has an irreplaceable role in the structure elucidation of small molecular products. However, the sample amount of trace components in phytochemical research is very low, and the traditional sampling method (uniform sampling) has problems of poor spectral quality and too long measure time. Increasing the number of scans results in several hours of the acquisition time for a single two-dimensional spectrum, which in turn causes strain on the NMR machine. The non-uniform sampling (NUS) technique can shorten the acquisition time to a large extent and not affect the quality of 2D NMR data, which greatly improves the efficiency of 2D NMR acquisition. In this paper, fuziline, a small molecular compound in the lateral roots of
9.Clinical guideline for diagnosis and treatment of nonunion of osteoporotic vertebral fractures (version 2025)
Haipeng SI ; Le LI ; Junjie NIU ; Wencan ZHANG ; Fuxin WEI ; Jinqiu YUAN ; Qiang YANG ; Hongli WANG ; Guangchao WANG ; Shihong CHEN ; Yunzhen CHEN ; Xiaoguang CHENG ; Jianwen DONG ; Shiqing FENG ; Rui GU ; Yong HAI ; Tianyong HOU ; Bo HUANG ; Xiaobing JIANG ; Lei ZANG ; Chunhai LI ; Nianhu LI ; Hua LIN ; Hongjian LIU ; Peng LIU ; Xinyu LIU ; Sheng LU ; Shibao LU ; Chunshan LUO ; Lvy CHAOLIANG ; Lvy WEIJIA ; Xuexiao MA ; Wei MEI ; Chunyang MENG ; Cailiang SHEN ; Chunli SONG ; Ruoxian SONG ; Jiacan SU ; Honglin TENG ; Hui SHENG ; Beiyu WANG ; Bingwu WANG ; Liang WANG ; Xiangyang WANG ; Nan WU ; Guohua XU ; Yayi XIA ; Jin XU ; Youjia XU ; Jianzhong XU ; Cao YANG ; Maowei YANG ; Zibin YANG ; Xiaojian YE ; Hailong YU ; Xijie YU ; Hua YUE ; Zhili ZENG ; Xinli ZHAN ; Hui ZHANG ; Peixun ZHANG ; Wei ZHANG ; Zhenlin ZHANG ; Jianguo ZHANG ; Tengyue ZHU ; Qiang LIU ; Huilin YANG
Chinese Journal of Trauma 2025;41(10):932-945
Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.
10.Problems and suggestions of medical equipment and devices in plateau field conditions
Lei LIANG ; Jiang-hui HAO ; Ze-rui ZHANG ; Feng ZHOU ; Can-hua XU ; Tao ZHANG
Chinese Medical Equipment Journal 2025;46(3):86-89
The characteristics of plateau field conditions and the application of the medical equipment and devices were summarized.The influences of plateau field conditions on the use and maintenance of the medical equipment and devices were pointed out,and some countermeasures were put forward accordingly.The causes for the problems were analyzed,and some suggestions were proposed from the aspects of top-level design,standard and personnel training.References were provided for the use and maintenance of medical equipment and devices during stationed field training and support for military operations other than war in plateau field areas.[Chinese Medical Equipment Journal,2025,46(3):86-89]

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