1.Effects of Different Microbial Fertilizers on Physiology and Rhizosphere Soil Environment of Codonopsis pilosula
Xia JIANG ; Junxi ZHAO ; Panpan SHI ; Xiaoxuan WANG ; Chenhui DU ; Shuosheng ZHANG ; Haixian ZHAN
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):241-251
ObjectiveTo study the effects of applying different microbial fertilizers on the growth and rhizosphere soil environment of Codonopsis pilosula and provide a theoretical basis for ecological cultivation of this medicinal plant. MethodsSeven groups were designed, including CK (no application of microbial fertilizer), T1 (Trichoderma longibrachiatum fertilizer), T2 (Bacillus subtilis fertilizer), T3 (Trichoderma viride fertilizer), T4 (compound microbial fertilizer), T5 (C. pilosula stems and leaves fermented with compound microbial fertilizer), and T6 (Scutellaria baicalensis stems and leaves fermented with T. viride fertilizer). The physiological indicators, yield, and quality of C. pilosula and the physicochemical properties, enzyme activities, and microbial diversity in the rhizosphere soil of different fertilizer treatments were measured. ResultsGroup T1 showed slight decreases in soluble protein content (SPC) and superoxide dismutase (SOD). Groups T2-T6 showed increases in physiological indicators such as proline (Pro), soluble solids content (SSC), SPC, catalase (CAT), and peroxidase (POD) and a decrease in malondialdehyde (MDA) in C. pilosula leaves. All the fertilizer treatments increased the yield of C. pilosula and the total polysaccharide content in the roots. T1, T2, T3, T4, and T5 increased the total flavonoid content in the roots. Meanwhile, T4 increased the total saponin content in the roots. All the fertilizer treatments reduced the pH and increased the electric conductivity (EC), soil organic matter (SOM), and alkaline nitrogen (AN) in the soil. T2 and T5 increased the available phosphorus (AP), and T3, T4, T5, and T6 increased the available potassium (AK) in the soil. All the fertilizer treatments increased the activities of urease, sucrase, and CAT in the soil. Except that T1 decreased the bacterial diversity in the soil, other fertilizer treatments significantly increased bacterial and fungal diversity in the soil. Different fertilizer treatments significantly affected the composition of bacterial and fungal communities in the soil. At the phylum level, the dominant bacterial phyla included Proteobacteria, Acidobacteriota, and Bacteroideta, and the dominant fungal phyla were Ascomycota, Mortierellomycota, and unclassified_fungi in the rhizosphere soil of C. pilosula after bacterial fertilizer treatment. At the genus level, unclassified Gemmatimonadaceae, Sphingomonas, and unclassified Vicinamibacteraceae were the dominant bacterial genera, while unidentified, unclassified Fungi, and unclassified Sordariomycetes were the dominant fungal genera in the rhizosphere soil. The results of redundancy analysis indicated that the main physicochemical factors affecting changes of microbial communities in the rhizosphere soil of C. pilosula were pH, EC, AK, AN, AP, and soil organic matter (SOM) in the soil. The correlation heatmap showed that Bryobacter had significantly positive correlations with EC, AK, and AN. There was a significantly negative correlation between Fusarium and SOM. In summary, applying an appropriate amount of microbial fertilizer can promote the growth and improve the rhizosphere soil environment of C. pilosula. ConclusionThe compound microbial fertilizer and the C. pilosula stems and leaves fermented with compound microbial fertilizer can improve the soil nutrients, growth, development, yield, and quality of C. pilosula, and thus they can be applied to the artificial cultivation of C. pilosula.
2.Effects of Different Microbial Fertilizers on Physiology and Rhizosphere Soil Environment of Codonopsis pilosula
Xia JIANG ; Junxi ZHAO ; Panpan SHI ; Xiaoxuan WANG ; Chenhui DU ; Shuosheng ZHANG ; Haixian ZHAN
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(13):241-251
ObjectiveTo study the effects of applying different microbial fertilizers on the growth and rhizosphere soil environment of Codonopsis pilosula and provide a theoretical basis for ecological cultivation of this medicinal plant. MethodsSeven groups were designed, including CK (no application of microbial fertilizer), T1 (Trichoderma longibrachiatum fertilizer), T2 (Bacillus subtilis fertilizer), T3 (Trichoderma viride fertilizer), T4 (compound microbial fertilizer), T5 (C. pilosula stems and leaves fermented with compound microbial fertilizer), and T6 (Scutellaria baicalensis stems and leaves fermented with T. viride fertilizer). The physiological indicators, yield, and quality of C. pilosula and the physicochemical properties, enzyme activities, and microbial diversity in the rhizosphere soil of different fertilizer treatments were measured. ResultsGroup T1 showed slight decreases in soluble protein content (SPC) and superoxide dismutase (SOD). Groups T2-T6 showed increases in physiological indicators such as proline (Pro), soluble solids content (SSC), SPC, catalase (CAT), and peroxidase (POD) and a decrease in malondialdehyde (MDA) in C. pilosula leaves. All the fertilizer treatments increased the yield of C. pilosula and the total polysaccharide content in the roots. T1, T2, T3, T4, and T5 increased the total flavonoid content in the roots. Meanwhile, T4 increased the total saponin content in the roots. All the fertilizer treatments reduced the pH and increased the electric conductivity (EC), soil organic matter (SOM), and alkaline nitrogen (AN) in the soil. T2 and T5 increased the available phosphorus (AP), and T3, T4, T5, and T6 increased the available potassium (AK) in the soil. All the fertilizer treatments increased the activities of urease, sucrase, and CAT in the soil. Except that T1 decreased the bacterial diversity in the soil, other fertilizer treatments significantly increased bacterial and fungal diversity in the soil. Different fertilizer treatments significantly affected the composition of bacterial and fungal communities in the soil. At the phylum level, the dominant bacterial phyla included Proteobacteria, Acidobacteriota, and Bacteroideta, and the dominant fungal phyla were Ascomycota, Mortierellomycota, and unclassified_fungi in the rhizosphere soil of C. pilosula after bacterial fertilizer treatment. At the genus level, unclassified Gemmatimonadaceae, Sphingomonas, and unclassified Vicinamibacteraceae were the dominant bacterial genera, while unidentified, unclassified Fungi, and unclassified Sordariomycetes were the dominant fungal genera in the rhizosphere soil. The results of redundancy analysis indicated that the main physicochemical factors affecting changes of microbial communities in the rhizosphere soil of C. pilosula were pH, EC, AK, AN, AP, and soil organic matter (SOM) in the soil. The correlation heatmap showed that Bryobacter had significantly positive correlations with EC, AK, and AN. There was a significantly negative correlation between Fusarium and SOM. In summary, applying an appropriate amount of microbial fertilizer can promote the growth and improve the rhizosphere soil environment of C. pilosula. ConclusionThe compound microbial fertilizer and the C. pilosula stems and leaves fermented with compound microbial fertilizer can improve the soil nutrients, growth, development, yield, and quality of C. pilosula, and thus they can be applied to the artificial cultivation of C. pilosula.
3.Resveratrol activates extracellular-regulated protein kinase 5 signaling protein to promote proliferation of mouse MC3T3-E1 cells
Yongkang NIU ; Zhiwei FENG ; Yaobin WANG ; Zhongcheng LIU ; Dejian XIANG ; Xiaoyuan LIANG ; Zhi YI ; Hongwei ZHAN ; Bin GENG ; Yayi XIA
Chinese Journal of Tissue Engineering Research 2025;29(5):908-916
BACKGROUND:The extracellular-regulated protein kinase 5(ERK5)signaling protein is essential for the survival of organisms,and resveratrol can promote osteoblast proliferation through various pathways.However,whether resveratrol can regulate osteoblast function through the ERK5 signaling protein needs further verification. OBJECTIVE:To explore the regulatory effect of ERK5 on the proliferation of MC3T3-E1 cells and related secreted proteins,and to further verify whether resveratrol can complete the above process by activating ERK5. METHODS:Mouse MC3T3-E1 preosteoblasts were treated with complete culture medium,XMD8-92(an ERK5 inhibitor),epidermal growth factor(an ERK5 activator),resveratrol alone,XMD8-92+EGF,and resveratrol+XMD8-92,respectively.Western blot assay was used to detect the expression of ERK5 and p-ERK5 proteins,proliferation-related proteins Cyclin D1,CDK4 and PCNA,and osteoblast-secreted proteins osteoprotegerin and receptor activator of nuclear factor-κB ligand in MC3T3-E1 cells of each group.The fluorescence intensity of ERK5,osteoprotegerin and receptor activator of nuclear factor-κB ligand in each group was detected by cell immunofluorescence staining,and cell proliferation was detected by EdU staining,respectively.The appropriate concentration and time of resveratrol intervention in MC3T3-E1 cells were determined by cell morphology observation and cell counting kit-8 assay. RESULTS AND CONCLUSION:The activation of ERK5 signaling protein could effectively promote the proliferation of MC3T3-E1 cells,up-regulate the osteoprotegerin/receptor activator of nuclear factor-κB ligand ratio.The appropriate concentration and time for resveratrol intervention in MC3T3-E1 cells was 5 μmol/L and 24 hours,respectively.Resveratrol could activate ERK5 signaling protein,thereby promoting osteoblast proliferation and up-regulating the osteoprotegerin/RANKL ratio.All these results indicate that resveratrol can promote the proliferation of MC3T3-E1 cells and up-regulate the osteoprotegerin/RANKL ratio by activating the ERK5 signaling protein.
4.Clinical research and characteristic analysis of patients with advanced colorectal cancer treated with Yinyang Gongji Pills and capecitabine.
Lei WANG ; Chao-Yue YAO ; Jie-Ru ZHAN ; Xiao-Xia SUN ; Zhong-Xin YU ; Xiao-Ya LIANG ; Jian WANG ; Xue GONG ; Da-Rong WEI
China Journal of Chinese Materia Medica 2025;50(5):1404-1411
Yinyang Gongji Pills have the effects of strengthening the body resistance to eliminate pathogenic factors, removing stasis, and reducing swelling, which is a commonly used traditional Chinese medicine(TCM) formula for treating intestinal accumulation. A real-world, registered, and single-arm clinical trial was conducted to observe the clinical efficacy and safety of Yinyang Gongji Pills combined with capecitabine in the treatment of advanced colorectal cancer and analyze the clinical characteristics of the patients. A total of 60 patients with advanced colorectal cancer who refused or could not tolerate standard treatment of western medicine were included in the study. They were treated with Yinyang Gongji Pills combined with capecitabine until disease progression or intolerable adverse events occurred. The main observation indicators were progression-free survival(PFS) and safety. The treatment effects of the patients under different baseline characteristics were analyzed. The clinical trial has found that the median PFS of all enrolled patients was 7.3 months, with 30.1% of patients having a PFS exceeding 12.0 months. Layered analysis showed that the median PFS of patients with the onset site being the colon and rectum were respectively 8.4 and 4.7 months. The median PFS of patients with high, medium, and low tumor burden were respectively 7.0, 4.7, and 10.8 months. The median PFS of patients with wild-type and mutant-type RAS/BRAF were respectively 7.9 and 6.9 months. The median PFS of patients with KPS scores ≥80 and ≤70 were respectively 7.9 and 6.5 months. The median PFS of patients treated with Yinyang Gongji Pills for ≥6, 3-6, and ≤3 months were respectively 8.0, 5.2, and 4.2 months. The median PFS of patients with spleen, kidney, liver, and lung syndrome differentiation in TCM were respectively 8.3, 6.7, 7.3, and 5.6 months. The median PFS of patients with TCM pathological factors including phlegm, dampness, and blood stasis were respectively 7.0, 7.3, and 6.5 months. Common adverse reactions include anemia, decreased white blood cells, decreased appetite, fatigue, and hand foot syndrome, with incidence rates being respectively 44.2%, 34.6%, 42.3%, 32.7%, and 17.3%. The results showed that the combination of Yinyang Gongji Pills and capecitabine demonstrated potential clinical efficacy and good safety in this study. The patients have clinical characteristics such as low tumor burden, onset site at the colon, KPS scores ≥ 80, long duration of oral TCM, and TCM syndrome differentiation including spleen or liver.
Humans
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Capecitabine/adverse effects*
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Colorectal Neoplasms/mortality*
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Drugs, Chinese Herbal/adverse effects*
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Male
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Middle Aged
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Female
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Aged
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Adult
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Treatment Outcome
5.eIF3a function in immunity and protection against severe sepsis by regulating B cell quantity and function through m6A modification.
Qianying OUYANG ; Jiajia CUI ; Yang WANG ; Ke LIU ; Yan ZHAN ; Wei ZHUO ; Juan CHEN ; Honghao ZHOU ; Chenhui LUO ; Jianming XIA ; Liansheng WANG ; Chengxian GUO ; Jianting ZHANG ; Zhaoqian LIU ; Jiye YIN
Acta Pharmaceutica Sinica B 2025;15(3):1571-1588
eIF3a is a N 6-methyladenosine (m6A) reader that regulates mRNA translation by recognizing m6A modifications of these mRNAs. It has been suggested that eIF3a may play an important role in regulating translation initiation via m6A during infection when canonical cap-dependent initiation is inhibited. However, the death of animal model studies impedes our understanding of the functional significance of eIF3a in immunity and regulation in vivo. In this study, we investigated the in vivo function of eIF3a using eIF3a knockout and knockdown mouse models and found that eIF3a deficiency resulted in splenic tissue structural disruption and multi-organ damage, which contributed to severe sepsis induced by Lipopolysaccharide (LPS). Ectopic eIF3a overexpression in the eIF3a knockdown mice rescued mice from LPS-induced severe sepsis. We further showed that eIF3a maintains a functional and healthy immune system by regulating B cell function and quantity through m6A modification of mRNAs. These findings unveil a novel mechanism underlying sepsis, implicating the pivotal role of B cells in this complex disease process regulated by eIF3a. Furthermore, eIF3a may be used to develop a potential strategy for treating sepsis.
6.Clinical trial on the combination of dinald cream and sertraline hydrochloride for skin itching in hemodialysis patients with uremic blood
Xiao-Xia CHEN ; Xi-Sheng XIE ; Zhi-Peng ZHAN
The Chinese Journal of Clinical Pharmacology 2024;40(20):2978-2982
Objective To evaluate the clinical efficacy and safety of desonide cream in combination with cetirizine hydrochloride for the treatment of skin itching in patients with uremia undergoing hemodialysis.Methods Patients with skin itching associated with uremia and hemodialysis were divided into control group and treatment group by random number table.The control group received oral cetirizine hydrochloride,10 mg per dose,once daily for 8 weeks.Patients in the treatment group were treated with desonide cream appropriate amout for external use on the basis of the treatment in the control group,once in the morning and once in the evening every day,and smeared on the pruritus of the patient's skin for 8 weeks.The clinical efficacy of the two groups were compared,and the pruritus symptoms,sleep quality and safety evaluation of the two groups were compared.Results During the trial,a total of 36 cases dropped out,with 52 cases ultimately included in the treatment and control groups,respectively.Following treatment,the total effective rates in the treatment and control groups were 82.69%(43 cases/52 cases)and 63.46%(33 cases/52 cases),respectively,showing statistically significant difference(P<0.05).After treatment,the visual analog scale(VAS)scores for the treatment and control groups were(2.87±1.29)and(3.62±1.76)points,respectively;the modified Dou's analogue grading(Dou's VAG)were(18.24±3.23)and(20.13±4.59)points,respectively;the Pittsburgh sleep quality index(PSQI)scores were(9.57±1.72)and(10.34±2.01)points,respectively.Compared with the control group,the above indexes in treatment group were statistically significant(all P<0.05).The adverse drug reactions of the treatment group were dizziness,nausea and vomiting,and the adverse drug reactions of the control group were dizziness,nausea and vomiting.The total incidence of adverse drug reactions in the treatment group and the control group was 9.62%(5 cases/52 cases)and 7.69%(4 cases/52 cases),respectively,and the difference was no statistically significant(P>0.05).Conclusion The combination of desonide cream and cetirizine hydrochloride has better efficacy and safety than cetirizine hydrochloride alone in treating the itching symptoms of uremic hemodialysis patients.
7.Investigation of the causes and analysis of influencing factors about interruption of menopausal hormone therapy
Ting ZHOU ; Xueyao PENG ; Xia ZHAN ; Hongrong BAO
China Pharmacy 2024;35(19):2411-2415
OBJECTIVE To investigate the reasons for interrupting menopausal hormone therapy in patients with menopausal syndrome and analyze the influencing factors that may lead to treatment interruption. METHODS The patients who visited our menopause medicine clinic from March 2022 to November 2023 and established a menopausal health manual were collected retrospectively. The case data were collected through the medical history registered in the manual and the outpatient medical record system. Telephone follow-up was conducted among the patients who had received menopausal hormone therapy to know about whether they were taking medication and to record the reasons for treatment interruption. Univariate analysis and multivariate Logistic regression analysis were adopted to investigate the influencing factors of discontinuing menopausal hormone therapy in patients with menopausal syndrome. RESULTS A total of 183 patients receiving menopause hormone therapy were enrolled. They were divided into interruption group (78 cases) and continuation group (105 cases) according to whether the treatment was interrupted. The results of telephone follow-up showed that the reasons in turn for interruption were perceiving ineffectiveness (16.67%), concerning about medication risk(15.38%), the existence of caution case(12.82%) and adverse reactions(10.26%). The results of univariate analysis showed that there were statistically significant differences in occupation, complications, medication regimen, bone condition and blood viscosity between the two groups (P<0.05). Multivariate Logistic regression analysis showed that the absence of complications, osteopenia and osteoporosis, working in public institution and retirement, and the continuous sequential medication regimen favored continuation of menopausal hormone therapy (P<0.05). CONCLUSIONS The interruption rate of menopausal hormone therapy is relatively high, and patients are greatly affected by perceiving ineffectiveness and concerning about medication risks, the existence of caution case, and adverse reactions. Complications can cause patients to interrupt treatment, while factors such as osteopenia and osteoporosis, working in public institutions and retirement, and continuous sequential medication regimens make patients more inclined to choose to continue menopausal hormone therapy.
8.Effect of Xiangsha Liu Junzitang Combined with Phlegm-removing and Detoxifying Traditional Chinese Medicine on Immune Escape in Lewis Lung Cancer Mice
Qian YANG ; Shumei WANG ; Shihan FENG ; Xue ZHAN ; Lintao XIA ; Mingxing WU
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(7):78-86
ObjectiveTo study the effect and mechanism of Xiangsha Liu Junzitang combined with phlegm-removing and detoxifying traditional Chinese medicine on immune escape in Lewis lung cancer mice. MethodA total of 60 specific-pathogen-free (SPF)-grade C57BL/6J male mice were injected subcutaneously with 0.2 mL of Lewis cell suspension (containing 2×106 cells·mL-1) in the right mid-axillary line. After 7 days, the mice that had been successfully modeled were randomly divided into six groups: the model group, the cisplatin group, the Xiangsha Liu Junzitang low-, medium-, and high-dose groups, and the combined group, with 10 mice in each group. The Xiangsha Liu Junzitang low-, medium- and high-dose groups were gavaged with 17.88, 35.75, 71.50 g·kg-1 Xiangsha Liu Junzitang solution once a day, respectively, and the dosage of cisplatin intraperitoneally injected into the mice was converted to 5 mg·kg-1 twice a week, and the tumour volumes of each group were measured every two days. The intervention lasted for 14 consecutive days. At the end of treatment, the tumour mass of mice in each group was weighed and the tumour inhibition rate was calculated. The morphological characteristics of tumours in each group were observed by hematoxylin-eosin (HE) staining. Fluorescent quantitative real-time polymerase chain reaction (Real-time PCR) assay was used to detect messenger ribonucleic acid (mRNA) contents of the natural killer group 2 member D (NKG2D) receptor, ribonucleic acid export-1 (RAE-1), and γ interferon (IFN-γ) in the tumour tissues of each group. NKG2D, RAE-1, and IFN-γ mRNA in tumour tissues of each group. Immunohistochemistry (IHC) and Western blot were applied to detect the expressions of RAE-1, NKG2D, and IFN-γ in tumour tissues of each group, and Western blot was used to detect the expressions of interleukin-6 (IL-6), Janus kinase 2 (JAK2), p-JAK2, signal transducer and activator of transcription 3 (STAT3), and p-STAT3 in tumour tissues of each group, as well as the protein levels of NKG2D, and RAE-1 in spleen tissues of each group. ResultCompared with that in the model group, the tumour mass decreased in all dose groups of Xiangsha Liu Junzitang, with no statistically significant difference. The tumour volume was reduced (P<0.05, P <0.01). The pathological morphology was improved. The mRNA contents of NKG2D, RAE-1 and IFN-γ were increased in the medium-dose group (P<0.05, P<0.01), and the protein expressions of NKG2D, RAE-1, and IFN-γ in tumour tissues were elevated (P<0.05, P<0.01), and p-JAK2 and p-STAT3 protein expressions were decreased (P<0.05, P<0.01). In spleen tissues, the protein expressions of NKG2D and RAE-1 in all dose groups of Xiangsha Liu Junzitang were significantly elevated (P<0.01). Compared with those in the cisplatin group, NKG2D, RAE-1 and IFN-γ mRNA contents were elevated in the middle-dose group of Xiangsha Liu Junzitang, and the difference was not statistically significant. IHC showed that the protein expressions of NKG2D and IFN-γ in the combined group were significantly elevated (P<0.01), and Western blot results showed that the protein expressions of RAE-1, NKG2D and IFN-γ were elevated (P<0.05, P<0.01). p-JAK2 and p-STAT3 protein expressions were decreased in the combined group (P<0.05, P<0.01). NKG2D and RAE-1 protein expressions were significantly increased in spleen tissues of the medium-dose groups and the combined group (P<0.01). ConclusionXiangsha Liu Junzitang combined with phlegm-removing and detoxifying traditional Chinese medicine can inhibit the growth of tumours in Lewis lung cancer mice by up-regulating the expressions of RAE-1/NKG2D, promoting the activation of NK cells, and inhibiting immune escape, the mechanism of which may be related to down-regulation of the JAK2/STAT3 pathway.
9.Herbal Textual Research on Euryales Semen in Famous Classical Formulas
Zixuan GAO ; Cheng QU ; Hui YAN ; Ling XIA ; Sheng GUO ; Zhilai ZHAN
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(11):210-217
This paper systematically combed and verified the name, origin, producing area, quality evaluation, harvesting, processing of Euryales Semen in famous classical formulas by consulting relevant ancient materia medica, medical books, prescription books and modern literature. The results showed that Euryales Semen was first collected by materia medica under the name of Jitoushi, and since the Ming dynasty, Qianshi has been used as a proper name and continues to this day, with other aliases such as Yanhuishi. Euryale ferox, a plant of the Nymphaeaceae family, is the same as that used in the past dynasties. However, due to long-term artificial domestication, the varieties vary with the origin, including Beiqian and Suqian. The medicinal part of Euryales Semen is mature seed kernel, its origin of ancient records mainly includes Shandong, Jiangsu, Henan and other places, since the Ming and Qing dynasties, Euryales Semen produced in Suzhou has been highly praised. Since modern times, it has gradually summarized and formed the best quality evaluation method of Euryales Semen with full grains, white cross-section, powdery enough and no broken powder. The harvesting time in the past dynasties was mainly August or in autumn. The main processing methods in the past dynasties included peeling for powder, pounding powder after steaming, drying and frying. Up to now, two mainstream processing methods of cleansing and stir-frying have been formed. Based on the research results, it is recommended that the mature seed kernel of E. ferox be used in famous classical formula Yihuangtang. Combined with the processing requirements of the original formula, it is suggested to refer to the stir-frying method in the general principles of processing of the current edition of Chinese Pharmacopoeia.
10.Effect of printing orientation on physical and mechanical properties of 3D printing prosthodontic base resin materials
Xinxin ZHAN ; Lulu CAO ; Dong XIANG ; Hao TANG ; Dandan XIA ; Hong LIN
Journal of Peking University(Health Sciences) 2024;56(2):345-351
Objective:To analyze the influence of forming direction on the surface characteristics,elastic modulus,bending strength and fracture toughness of printed parts and the relationship between forming direction and force direction,and to provide scientific basis and guidance for the clinical applica-tion of oral denture base resin materials.Methods:The 3D printing technology was used to print denture base resin samples.The shape and size of the samples referred to the current standard for testing conven-tional denture base materials.The samples used for physical performance testing were cylindrical(with a diameter of 15 mm and a thickness of 1 mm)and printed at different angles along the Z axis(0°,45°,90°).Scanning electron microscope was used to observe the microscopic topography of the different sam-ples.The color stability of different samples was observed by color stabilizer.The surface roughness of the samples was analyzed by using surface roughness tester.The Vickers hardness was measured to ana-lyze the hardness of the samples.The samples used for mechanical performance testing were rectangular(elastic modulus and bending strength:A length of 64 mm,a width of 10 mm,and a height of 3.3 mm;fracture toughness:A length of 39 mm,a width of 8 mm,and a height of 4 mm),divided into two groups:W group and H group.The W group was printed from the bottom up along the Z axis with the length × width as the bottom surface parallel to the X,Y axis plane,while the H group printed from the bottom up along the Z axis with the length × height as the bottom surface parallel to the X,Y axis plane.The forming angles of both groups were equally divided into 0°,45°,and 90°.The elastic modulus,bending strength and fracture toughness of different samples were studied through universal mechanical testing machine.SPSS 22.0 software was used for statistical analysis.Results:The microscopic topogra-phy and roughness of different samples were closely related to the printing direction,with significant differences between the 0°,45°,and 90° specimens.The 0° specimens had the smoothest surface(roughness<1 μm).The surface of the 45 ° specimen was the roughest(roughness>3 μm).The microhardness of the 0° sample was the best[(196.13±0.20)MPa],with a significant difference com-pared with the 90° sample[(186.62±4.81)MPa,P<0.05].The mechanical properties of different samples were also closely related to the printing direction.The elastic modulus,bending strength,and fracture toughness of the 45° samples in the W group were the highest compared with the other groups.The results of elastic modulus showed that in the H group,the 45° specimens had the highest elastic mo-dulus,which was significantly different from the 0° and 90° specimens(P<0.05).The elastic modulus of 0° and 45° specimens in the W group were higher than those in 90° specimens(P<0.05).The bending strength results showed that there was no significant difference between the specimens from dif-ferent angles in the H group.The bending strength of the 90° specimens in the W group was the smallest,and there was a significant difference between 90° and the 0° and 45° specimens(P<0.05);And the bendind strength of the 0° and 45° specimens in the W group was significantly higher than that of the 0° and 45° specimens in the H group(P<0.05).The fracture toughness results showed that the fracture toughness of the H group specimens was lower than 1.9 MPa m1/2,which was specified in the denture base standard.The 45° samples in the W group were the highest,with significant differences compared with the 0° and 90° samples(P<0.05).And the 90° samples of the W group specimens were lower than 1.9 MPa m1/2.And the fracture toughness of the 45° specimen in the W group was significantly higher than that of all the specimens in the H group(P<0.05).Conclusion:The 0° samples had rela-tively better physical properties.The 45° samples had the best mechanical properties.But the fracture toughness of specimens(H group and 90° samples of W group)did not yet meet clinical requirements.That indicated that the characteristics of the 3D printing denture base resin were affected by the printing direction.Only when the performance of the printed samples in all directions met the minimum require-ments of the standard,they could be used in clinical practice.

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