1.Compatibility of commonly used intravenous drugs in ICU patients with severe pneumonia
Lei ZHANG ; Xiao LI ; Jing WANG ; Xiaokai REN ; Zhanjun DONG
China Pharmacy 2026;37(14):1886-1891
OBJECTIVE To quantitatively assess the compatibility risk of commonly used intravenous drugs in intensive care unit (ICU) patients with severe pneumonia, and provide a reference for reducing the incidence of adverse events caused by incompatibility. METHODS The PASS clinical pharmacy management system was used to retrospectively collect the data of patients diagnosed with “severe pneumonia” in the ICU of Hebei General Hospital from January 2023 to June 2025, and the commonly used intravenous drugs and medication frequency were extracted. Based on authoritative databases such as Micromedex and Stabilis as well as relevant literature, the compatibility data of commonly used intravenous drugs with 0.9% Sodium chloride injection and 5% Glucose injection were summarized. The theoretical and actual compatibility risk values were calculated using formulas, and high-risk drugs were screened and the compatibility query table was drawn. RESULTS A total of 158 ICU patients with severe pneumonia were treated with 89 intravenous drugs, and 24 drugs with high compatibility risk were identified. The drug with the highest theoretical compatibility risk value was Amphotericin B for injection (risk value 146), and the drug with the highest actual compatibility risk value was Propofol medium and long chain fat emulsion injection (risk value 8 740). Among the 24 high-risk drugs, six drugs, namely Esomeprazole sodium for injection, Ambroxol hydrochloride injection, Midazolam injection, Methylprednisolone sodium succinate for injection, Furosemide injection, and Cefoperazone sodium and sulbactam sodium for injection, simultaneously ranked among the top 15 in both theoretical and actual compatibility risk rankings. Among 650 pairwise compatibility combinations of the 24 drugs, 24.62% were compatible, 11.23% were incompatible, 6.77% had conflicting evidence, and 57.38% had missing evidence. CONCLUSIONS This study quantitatively analyzed the medication safety of commonly used intravenous drugs in ICU patients with severe pneumonia, identified 24 drugs with high compatibility risk, and established a compatibility query table for high-risk drugs, which helps reduce the risk of ICU compatibility adverse events.
2.Associations between statins and all-cause mortality and cardiovascular events among peritoneal dialysis patients: A multi-center large-scale cohort study.
Shuang GAO ; Lei NAN ; Xinqiu LI ; Shaomei LI ; Huaying PEI ; Jinghong ZHAO ; Ying ZHANG ; Zibo XIONG ; Yumei LIAO ; Ying LI ; Qiongzhen LIN ; Wenbo HU ; Yulin LI ; Liping DUAN ; Zhaoxia ZHENG ; Gang FU ; Shanshan GUO ; Beiru ZHANG ; Rui YU ; Fuyun SUN ; Xiaoying MA ; Li HAO ; Guiling LIU ; Zhanzheng ZHAO ; Jing XIAO ; Yulan SHEN ; Yong ZHANG ; Xuanyi DU ; Tianrong JI ; Yingli YUE ; Shanshan CHEN ; Zhigang MA ; Yingping LI ; Li ZUO ; Huiping ZHAO ; Xianchao ZHANG ; Xuejian WANG ; Yirong LIU ; Xinying GAO ; Xiaoli CHEN ; Hongyi LI ; Shutong DU ; Cui ZHAO ; Zhonggao XU ; Li ZHANG ; Hongyu CHEN ; Li LI ; Lihua WANG ; Yan YAN ; Yingchun MA ; Yuanyuan WEI ; Jingwei ZHOU ; Yan LI ; Caili WANG ; Jie DONG
Chinese Medical Journal 2025;138(21):2856-2858
3.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
;
Alzheimer Disease/metabolism*
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Computational Biology
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Mice, Inbred C57BL
;
High-Throughput Nucleotide Sequencing
;
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
4.Xinyang Tablets ameliorate ventricular remodeling in heart failure via FTO/m6A signaling pathway.
Dong-Hua LIU ; Zi-Ru LI ; Si-Jing LI ; Xing-Ling HE ; Xiao-Jiao ZHANG ; Shi-Hao NI ; Wen-Jie LONG ; Hui-Li LIAO ; Zhong-Qi YANG ; Xiao-Ming DONG
China Journal of Chinese Materia Medica 2025;50(4):1075-1086
The study was conducted to investigate the mechanism of Xinyang Tablets( XYP) in modulating the fat mass and obesity-associated protein(FTO)/N6-methyladenosine(m6A) signaling pathway to ameliorate ventricular remodeling in heart failure(HF). A mouse model of HF was established by transverse aortic constriction(TAC). Mice were randomized into sham, model, XYP(low, medium, and high doses), and positive control( perindopril) groups(n= 10). From day 3 post-surgery, mice were administrated with corresponding drugs by gavage for 6 consecutive weeks. Following the treatment, echocardiography was employed to evaluate the cardiac function, and RT-qPCR was employed to determine the relative m RNA levels of key markers, including atrial natriuretic peptide( ANP), B-type natriuretic peptide( BNP), β-myosin heavy chain(β-MHC), collagen type I alpha chain(Col1α), collagen type Ⅲ alpha chain(Col3α), alpha smooth muscle actin(α-SMA), and FTO. The cardiac tissue was stained with Masson's trichrome and wheat germ agglutinin(WGA) to reveal the pathological changes. Immunohistochemistry was employed to detect the expression levels of Col1α, Col3α, α-SMA, and FTO in the myocardial tissue. The m6A modification level in the myocardial tissue was measured by the m6A assay kit. An H9c2 cell model of cardiomyocyte injury was induced by angiotensin Ⅱ(AngⅡ), and small interfering RNA(siRNA) was employed to knock down FTO expression. RT-qPCR was conducted to assess the relative m RNA levels of FTO and other genes associated with cardiac remodeling. The m6A modification level was measured by the m6A assay kit, and Western blot was employed to determine the phosphorylated phosphatidylinositol 3-kinase(p-PI3K)/phosphatidylinositol 3-kinase(PI3K) and phosphorylated serine/threonine kinase(p-Akt)/serine/threonine kinase(Akt) ratios in cardiomyocytes. The results of animal experiments showed that the XYP treatment significantly improved the cardiac function, reduced fibrosis, up-regulated the m RNA and protein levels of FTO, and lowered the m6A modification level compared with the model group. The results of cell experiments showed that the XYP-containing serum markedly up-regulated the m RNA level of FTO while decreasing the m6A modification level and the p-PI3K/PI3K and p-Akt/Akt ratios in cardiomyocytes. Furthermore, FTO knockdown reversed the protective effects of XYP-containing serum on Ang Ⅱ-induced cardiomyocyte hypertrophy. In conclusion, XYP may ameliorate ventricular remodeling by regulating the FTO/m6A axis, thereby inhibiting the activation of the PI3K/Akt signaling pathway.
Animals
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Ventricular Remodeling/drug effects*
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Heart Failure/physiopathology*
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Signal Transduction/drug effects*
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Mice
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Male
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Alpha-Ketoglutarate-Dependent Dioxygenase FTO/genetics*
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Drugs, Chinese Herbal/administration & dosage*
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Mice, Inbred C57BL
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Humans
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Adenosine/analogs & derivatives*
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Myocytes, Cardiac/metabolism*
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Disease Models, Animal
5.Efficacy and mechanism of Guizhi Tongluo Tablets in alleviating atherosclerosis by inhibiting CD72hi macrophages.
Xing-Ling HE ; Si-Jing LI ; Zi-Ru LI ; Dong-Hua LIU ; Xiao-Jiao ZHANG ; Huan HE ; Xiao-Ming DONG ; Wen-Jie LONG ; Wei-Wei ZHANG ; Hui-Li LIAO ; Lu LU ; Zhong-Qi YANG ; Shi-Hao NI
China Journal of Chinese Materia Medica 2025;50(5):1298-1309
This study investigates the effect and underlying mechanism of Guizhi Tongluo Tablets(GZTL) in treating atherosclerosis(AS) in a mouse model. Apolipoprotein E-knockout(ApoE~(-/-)) mice were randomly assigned to the following groups: model, high-, medium-, and low-dose GZTL, and atorvastatin(ATV), and age-matched C57BL/6J mice were selected as the control group. ApoE~(-/-) mice in other groups except the control group were fed with a high-fat diet for the modeling of AS and administrated with corresponding drugs via gavage for 8 weeks. General conditions, signs of blood stasis, and body mass of mice were monitored. Aortic plaques and their stability were assessed by hematoxylin-eosin, Masson, and oil red O staining. Serum levels of total cholesterol(TC), triglycerides(TG), and low-density lipoprotein cholesterol(LDL-C) were measured by biochemical assays, and those of interleukin-1β(IL-1β), tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6) were determined via enzyme-linked immunosorbent assay. Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL). Single-cell RNA sequencing(scRNA-seq) was employed to analyze the differential expression of CD72hi macrophages(CD72hi-Mφ) in the aortas of AS patients and mice. The immunofluorescence assay was employed to visualize CD72hi-Mφ expression in mouse aortic plaques, and real-time fluorescence quantitative PCR was utilized to determine the mRNA levels of IL-1β, TNF-α, and IL-6 in the aorta. The results demonstrated that compared with the control group, the model group exhibited significant increases in body mass, aortic plaque area proportion, necrotic core area proportion, and lipid deposition, a notable decrease in collagen fiber content, and an increase in apoptosis. Additionally, the model group showcased elevated serum levels of TC, TG, LDL-C, IL-1β, TNF-α, and IL-6, alongside marked upregulations in the mRNA levels of IL-1β, TNF-α, and IL-6 in the aorta. In comparison with the model group, the GZTL groups and the ATV group showed a reduction in body mass, and the medium-and high-dose GZTL groups and the ATV group demonstrated reductions in aortic plaque area proportion, necrotic core area proportion, and lipid deposition, an increase in collagen fiber content, and a decrease in apoptosis. Furthermore, the treatment goups showcased lowered serum levels of TC, TG, LDL-C, IL-1β, TNF-α, and IL-6. The data of scRNA-seq revealed significantly elevated CD72hi-Mφ signaling in carotid plaques of AS patients compared with that in the normal arterial tissue. Animal experiments confirmed that CD72hi-Mφ expression, along with several pro-inflammatory cytokines, was significantly upregulated in the aortas of AS mice, which were downregulated by GZTL treatment. In conclusion, GZTL may alleviate AS by inhibiting CD72hi-Mφ activity.
Animals
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Drugs, Chinese Herbal/administration & dosage*
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Atherosclerosis/immunology*
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Mice
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Mice, Inbred C57BL
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Macrophages/immunology*
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Male
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Humans
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Apolipoproteins E/genetics*
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Tablets
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Tumor Necrosis Factor-alpha/genetics*
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Apoptosis/drug effects*
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Interleukin-1beta/genetics*
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Interleukin-6/genetics*
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Disease Models, Animal
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Mice, Knockout
6.Phenylpropanoids from roots of Berberis polyantha.
Dong-Mei SHA ; Shuai-Cong NI ; Li-Niu SHA-MA ; Hai-Xiao-Lin-Mo MA ; Xiao-Yong HE ; Bin HE ; Shao-Shan ZHANG ; Ying LI ; Jing WEN ; Yuan LIU ; Xin-Jia YAN
China Journal of Chinese Materia Medica 2025;50(6):1564-1568
The chemical constituents were systematically separated from the roots of Berberis polyantha by various chromatographic methods, including silica gel column chromatography, HP20 column chromatography, polyamide column chromatography, reversed-phase C_(18) column chromatography, and preparative high-performance liquid chromatography. The structures of the compounds were identified by physicochemical properties and spectroscopic techniques(1D NMR, 2D NMR, UV, MS, and CD). Four phenylpropanoids were isolated from the methanol extract of the roots of B. polyantha, and they were identified as(2R)-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone-O-β-D-glucopyranoside(1), methyl 4-hydroxy-3,5-dimethoxybenzoate(2),(+)-syringaresinol(3), and syringaresinol-4-O-β-D-glucopyranoside(4). Compound 1 was a new compound, and other compounds were isolated from this plant for the first time. The anti-inflammatory activity of these compounds was evaluated based on the release of nitric oxide(NO) in the culture of lipopolysaccharide(LPS)-induced RAW264.7 macrophages. At a concentration of 10 μmol·L~(-1), all the four compounds inhibited the LPS-induced release of NO in RAW264.7 cells, demonstrating potential anti-inflammatory properties.
Plant Roots/chemistry*
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Animals
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Mice
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Berberis/chemistry*
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RAW 264.7 Cells
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Macrophages/immunology*
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Drugs, Chinese Herbal/isolation & purification*
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Nitric Oxide/metabolism*
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Molecular Structure
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Anti-Inflammatory Agents/isolation & purification*
7.Chemical and pharmacological research progress on Mongolian folk medicine Syringa pinnatifolia.
Kun GAO ; Chang-Xin LIU ; Jia-Qi CHEN ; Jing-Jing SUN ; Xiao-Juan LI ; Zhi-Qiang HUANG ; Ye ZHANG ; Pei-Feng XUE ; Su-Yi-le CHEN ; Xin DONG ; Xing-Yun CHAI
China Journal of Chinese Materia Medica 2025;50(8):2080-2089
Syringa pinnatifolia, belonging to the family Oleaceae, is a species endemic to China. It is predominantly distributed in the Helan Mountains region of Inner Mongolia and Ningxia of China. The peeled roots, stems, and thick branches have been used as a distinctive Mongolian medicinal material known as "Shan-chen-xiang", which has effects such as suppressing "khii", clearing heat, and relieving pain and is employed for the treatment of cardiovascular and pulmonary diseases and joint pain. Over the past five years, significant increase was achieved in research on chemical constituents and pharmacological effects. There were a total of 130 new constituents reported, covering sesquiterpenoids, lignans, and alkaloids. Its effects of anti-myocardial ischemia, anti-cerebral ischemia/reperfusion, sedation, and analgesia were revealed, and the mechanisms of agarwood formation were also investigated. To better understand its medical value and potential of clinical application, this review updates the research progress in recent five years focusing on the chemical constituents and pharmacological effects of S. pinnatifolia, providing reference for subsequent research on active ingredient and support for its innovative application in modern medicine system.
Medicine, Mongolian Traditional
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Humans
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Drugs, Chinese Herbal/pharmacology*
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Animals
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Syringa/chemistry*
8.International clinical practice guideline on the use of traditional Chinese medicine for functional dyspepsia (2025).
Sheng-Sheng ZHANG ; Lu-Qing ZHAO ; Xiao-Hua HOU ; Zhao-Xiang BIAN ; Jian-Hua ZHENG ; Hai-He TIAN ; Guan-Hu YANG ; Won-Sook HONG ; Yu-Ying HE ; Li LIU ; Hong SHEN ; Yan-Ping LI ; Sheng XIE ; Jin SHU ; Bin-Fang ZENG ; Jun-Xiang LI ; Zhen LIU ; Zheng-Hua XIAO ; Jing-Dong XIAO ; Pei-Yong ZHENG ; Shao-Gang HUANG ; Sheng-Liang CHEN ; Gui-Jun FEI
Journal of Integrative Medicine 2025;23(5):502-518
Functional dyspepsia (FD), characterized by persistent or recurrent dyspeptic symptoms without identifiable organic, systemic or metabolic causes, is an increasingly recognized global health issue. The objective of this guideline is to equip clinicians and nursing professionals with evidence-based strategies for the management and treatment of adult patients with FD using traditional Chinese medicine (TCM). The Guideline Development Group consulted existing TCM consensus documents on FD and convened a panel of 35 clinicians to generate initial clinical queries. To address these queries, a systematic literature search was conducted across PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI), VIP Database, China Biology Medicine (SinoMed) Database, Wanfang Database, Traditional Medicine Research Data Expanded (TMRDE), and the Traditional Chinese Medical Literature Analysis and Retrieval System (TCMLARS). The evidence from the literature was critically appraised using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. The strength of the recommendations was ascertained through a consensus-building process involving TCM and allopathic medicine experts, methodologists, pharmacologists, nursing specialists, and health economists, leveraging their collective expertise and empirical knowledge. The guideline comprises a total of 43 evidence-informed recommendations that span a range of clinical aspects, including the pathogenesis according to TCM, diagnostic approaches, therapeutic interventions, efficacy assessments, and prognostic considerations. Please cite this article as: Zhang SS, Zhao LQ, Hou XH, Bian ZX, Zheng JH, Tian HH, Yang GH, Hong WS, He YY, Liu L, Shen H, Li YP, Xie S, Shu J, Zeng BF, Li JX, Liu Z, Xiao ZH, Xiao JD, Zheng PY, Huang SG, Chen SL, Fei GJ. International clinical practice guideline on the use of traditional Chinese medicine for functional dyspepsia (2025). J Integr Med. 2025; 23(5):502-518.
Dyspepsia/drug therapy*
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Humans
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Medicine, Chinese Traditional/methods*
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Practice Guidelines as Topic
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Drugs, Chinese Herbal/therapeutic use*
9.Effects of Laparoscopic Sleeve Gastrectomy on Cardiac Structure and Function in Obese Patients With Heart Failure.
Xiao-Yan JIA ; Rui-Jia LIAN ; Bao-Dong MA ; Yang-Xi HU ; Qin-Jun CHU ; Hai-Yun JING ; Zhi-Qiang KANG ; Jian-Ping YE ; Xi-Wen MA
Acta Academiae Medicinae Sinicae 2025;47(2):226-236
Objective To investigate the effects of laparoscopic sleeve gastrectomy(LSG)on the cardiac structure and function in obese patients with heart failure(HF)and compare the efficacy of LSG across obese patients with different HF types.Methods This study included 33 obese patients with HF who underwent LSG.The clinical indicators were compared between before operation and 12 months after operation.Repeated measures analysis of variance was employed to evaluate the changes in echocardiographic parameters before operation and 3,6,and 12 months after operation.Patients were allocated into a HF with preserved ejection fraction group(n=17),a HF with mildly reduced ejection fraction group(n=5)and a HF with reduced ejection fraction(HFrEF)group(n=11)based on left ventricular ejection fraction(LVEF)before operation for subgroup analyses of the effects of LSG on the cardiac structure and function of obese patients with HF.The paired samples t-test was conducted to assess the degree of cardiac structural and functional alterations after LSG.Results The 33 patients included 69.7% males,with an average age of(35.3±9.9)years,and a body mass index(BMI)of(51.2±9.8)kg/m2.The median follow-up was 9.0(5.0,13.3)months.Compared with the preoperative values,the postoperative BMI(P=0.002),body surface area(BSA)(P=0.009),waist circumference(P=0.010),hip circumference(P=0.031),body fat content(P=0.007),and percentage of patients with cardiac function grades Ⅲ-IV(P<0.001)decreased.At the 12-month follow-up left atrial diameter(P=0.006),right atrial long-axis inner diameter(RAD1)(P<0.001),right atrial short-axis inner diameter(RAD2)(P<0.001),right ventricular inner diameter(P=0.002),interventricular septal thickness at end-diastolic(P=0.002),and left ventricular end-diastolic volumes(P=0.004)and left ventricular end-systolic volumes(P=0.003) all significantly reduced compared with preoperative values.Additionally,left ventricular fractional shortening and LVEF improved(both P<0.001).Subgroup analyses revealed that cardiac structural parameters significantly decreased in the HF with preserved ejection fraction,HF with mildly reduced ejection fraction,and HFrEF subgroups compared with preoperative values.Notably,the HFrEF group demonstrated the best performance in terms of left atrial diameter(P=0.003),left ventricular inner diameter at end-diastole(P=0.008),RAD1(P<0.001),RAD2(P=0.004),right ventricular inner diameter(P=0.019),left ventricular end-diastolic volume(P=0.004)and left ventricular end-systolic volume(P=0.001),cardiac output(P=0.006),tricuspid regurgitation velocity(P=0.002),and pulmonary artery systolic pressure(P=0.001) compared to preoperatively.Postoperative left ventricular fractional shortening(P<0.001,P=0.003,P<0.001)and LVEF(P<0.001,P=0.011,P=0.001)became higher in all the three subgroups than the preoperative values.Conclusions LSG decreased the body weight,BMI,and BSA,improved the cardiac function grade,reversed the enlargement of the left atrium and left ventricle,reduced the right atrium and right ventricle,and enhanced the left ventricular systolic function.It was effective across obese patients with different HF types.Particularly,LSG demonstrates the best performance in improving the structures of both atria and ventricles in obese patients with HFrEF.
Humans
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Male
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Female
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Gastrectomy/methods*
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Heart Failure/complications*
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Adult
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Obesity/physiopathology*
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Laparoscopy
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Middle Aged
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Heart/physiopathology*
;
Stroke Volume
10.Reliable Extraction of Seawater Nd and Hf Isotope Compositions from Fe-Mn Oxyhydroxide Fraction of Marine Sediments in the Arctic Ocean
Ying ZHANG ; Lin-Sen DONG ; Hong-Min WANG ; Xiao-Jing WANG ; Lian-Hua HE ; Yan-Guang LIU ; Ji-Hua LIU
Chinese Journal of Analytical Chemistry 2025;53(8):1380-1390
Combined seawater Hf and Nd isotope compositions have been applied as reliable tracers of water mass mixing and weathering input changes.The establishment of standardized synchronous extraction methods for Fe-Mn oxyhydroxide in sediments,which serve as effective carriers for isotopic signals of ancient seawater,is a prerequisite and key for paleoceanography research.The research material of this study was the surface sediments of the Western Arctic Ocean obtained from China's 7th Arctic Scientific Expedition,and a reliable simultaneous Nd-Hf isotope extraction method in Fe-Mn oxyhydroxide fraction was established through systematic optimization of pretreatment procedures and key extraction parameters.This research focused on analyzing the effects of pretreatment(Milli-Q water pre-wash)and key extraction parameters(leaching time,solution/solid ratios,concentration of EDTA-2Na,and concentration of mixed solution of hydroxyamine hydrochloride(HH)and acetic acid(HAc))on element extraction efficiency and isotopic composition.The experimental results indicated that the Milli-Q water pre-wash was not necessary,Fe-Mn oxyhydroxide extraction could be directly performed.Nd extraction amount in Fe-Mn oxyhydroxide fraction was not sensitive to changes in extraction conditions,while the Hf extraction amount was significantly affected by leaching time,solution/solid ratios and concentration of EDTA-2Na.The optimal conditions for synchronously extracting Nd-Hf isotopes were as follows:adding 20 mL of a mixed solution of 0.005 mol/L HH+1.5%HAc+0.03 mol/L EDTA-2Na per gram of sample,and reaction at room temperature for 3 h under shaking.Through systematic verification of 87Sr/86Sr ratio,εNd value,εHf value,Al/Nd ratio and Al/Hf ratio,it was confirmed that this method could effectively avoid interferences from residual components and accurately obtain Nd-Hf isotope signals of ancient seawater preserved in sediments.The standardized method established in this work provided reliable technical support for reconstructing water mass mixing between the Arctic,North Atlantic,and North Pacific Oceans and riverine input histories.It also provided important reference for the extraction methods of Nd and Hf isotopes from marine sources in sediments from other sea areas around the world.

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