ObjectiveTo investigate the influence of histone deacetylase 3 (HDAC3) on the occurrence, development of psoriasis-like inflammation in mice, and the relative immune mechanisms. MethodsHealthy C57BL/6 mice aged 6-8 weeks were selected and randomly divided into 3 groups: control group (Control), psoriasis model group (IMQ), and HDAC3 inhibitor RGFP966-treated psoriasis model group (IMQ+RGFP966). One day prior to the experiment, the back hair of the mice was shaved. After a one-day stabilization period, the mice in Control group was treated with an equal amount of vaseline, while the mice in IMQ group was treated with imiquimod (62.5 mg/d) applied topically on the back to establish a psoriasis-like inflammation model. The mice in IMQ+RGFP966 group received intervention with a high dose of the HDAC3-selective inhibitor RGFP966 (30 mg/kg) based on the psoriasis-like model. All groups were treated continuously for 5 d, during which psoriasis-like inflammation symptoms (scaling, erythema, skin thickness), body weight, and mental status were observed and recorded, with photographs taken for documentation. After euthanasia, hematoxylin-eosin (HE) staining was used to assess the effect of RGFP966 on the skin tissue structure of the mice, and skin thickness was measured. The mRNA and protein expression levels of HDAC3 in skin tissues were detected using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB), respectively. Flow cytometry was employed to analyze neutrophils in peripheral blood and lymph nodes, CD4⁺ T lymphocytes, CD8⁺ T lymphocytes in peripheral blood, and IL-17A secretion by peripheral blood CD4⁺ T lymphocytes. Additionally, spleen CD4⁺ T lymphocyte expression of HDAC3, CCR6, CCR8, and IL-17A secretion levels were analyzed. Immunohistochemistry was used to detect the localization and expression levels of HDAC3, IL-17A, and IL-10 in skin tissues. ResultsCompared with the Control group, the IMQ group exhibited significant psoriasis-like inflammation, characterized by erythema, scaling, and skin wrinkling. Compared with the IMQ group, RGFP966 exacerbated psoriasis-like inflammatory symptoms, leading to increased hyperkeratosis. The psoriasis area and severity index (PASI) skin symptom scores were higher in the IMQ group than those in the Control group, and the scores were further elevated in the IMQ+RGFP966 group compared to the IMQ group. Skin thickness measurements showed a trend of IMQ+RGFP966>IMQ>Control. The numbers of neutrophils in the blood and lymph nodes increased sequentially in the Control, IMQ, and IMQ+RGFP966 groups, with a similar trend observed for CD4⁺ and CD8⁺ T lymphocytes in the blood. In skin tissues, compared with the Control group, the mRNA and protein levels of HDAC3 decreased in the IMQ group, but RGFP966 did not further reduce these expressions. HDAC3 was primarily located in the nucleus. Compared with the Control group, the nuclear HDAC3 content decreased in the skin tissues of the IMQ group, and RGFP966 further reduced nuclear HDAC3. Compared with the Control and IMQ groups, RGFP966 treatment decreased HDAC3 expression in splenic CD4⁺ and CD8⁺ T cells. RGFP966 treatment increased the expression of CCR6 and CCR8 in splenic CD4⁺ T cells and enhanced IL-17A secretion by peripheral blood and splenic CD4⁺ T lymphocytes. Additionally, compared with the IMQ group, RGFP966 reduced IL-10 protein levels and upregulated IL-17A expression in skin tissues. ConclusionRGFP966 exacerbates psoriatic-like inflammatory responses by inhibiting HDAC3, increasing the secretion of the cytokine IL-17A, and upregulating the expression of chemokines CCR8 and CCR6.

Objective To evaluate the effects of high-fat diet on the pharmacokinetics of metronidazole in Chinese healthy adult subjects.Methods This program is designed according to a single-center,randomized,open,single-dose trial.Forty-seven healthy subjects were assigned to receive single dose of metronidazole tablets 200 mg in either fasting and high-fat diet state,and blood samples were taken at different time points,respectively.The concentrations of metronidazole in plasma were determined by high performance liquid chromatography-mass spectromentry.Results The main pharmacokinetic parameters of metronidazole in fasting state and high-fat diet state were as follows:Cmax were(4 799.13±1 195.32)and(4 044.17±773.98)ng·mL-1;tmax were 1.00 and 2.25 h;t1/2 were(9.11±1.73)and(9.37±1.79)h;AUC0_t were(5.59±1.19)x 104 and(5.51±1.18)x 104 ng·mL-1·h;AUC0_∞ were(5.79±1.33)x 104 and(5.74±1.32)× 104 ng·mL-1·h.Compared to the fasting state,the tmaxof the drug taken after a high fat diet was delayed by 1.25 h(P＜0.01),Cmax,AUC0_t,AUC0-∞ were less or decreased in different degrees,but the effects were small(all P＞0.05).Conclusion High-fat diet has little effects on the pharmacokinetic parameters of metronidazole,which does not significantly change the degree of drug absorption,but can significantly delay the time to peak.

Colitis-associated cancer(CAC)is a specific type of colorectal cancer that develops from inflammatory bowel disease(IBD).Myeloid-derived suppressor cells(MDSCs)are a group of myeloid cells with immunosuppressive properties,and MDSCs in the tumor microenvironment proliferate and activate during the development of colitis-associated cancer,inhibiting T-cell production and impairing their function,which impedes the immunotherapeutic effect of colitis-associated cancer.In this paper,we review the immunosuppressive mechanisms of MDSCs in the development of inflammatory bowel disease to colitis-associated cancers and the current drugs targeting MDSCs for immunotherapy of inflammatory colorectal cancers,with a view to providing new strategies for the treatment of colitis-associated cancers.

Tranexamic acid is widely used in joint orthopedic surgery.At the same time,it has high safety and few adverse drug reactions.It can effectively improve intraoperative bleeding and promote early functional recovery of patients.This article reviews the mode of administration,safe dose,administration time and adverse drug reactions of tranexamic acid in the perioperative period of joint replacement and arthroscopic surgery,in order to provide reference for the clinical application of tranexamic acid.

Objective To investigate the effects of cinbufagin(CB)on the proliferation,migration and invasion ability as well as epithelial-mesenchymal transition(EMT)of human colon cells HCT116.Methods Logarithmically grown HCT116 cells were randomly divided into blank group and experimental-L,-M,-H groups;the blank group did not receive any treatment(0 nmol·L-1),and experimental-L,-M,-H groups were cultured in 1 640 medium containing 17.5,35 and 70 nmol·L-1 cinbufagin for 48 h.Cell counting kit-8(CCK-8)was used to detect the effect of cinbufagin on the survival rate of HCT116 cells;cloning assay was used to detect the effect of cinbufagin on the proliferation of HCT116 cells;cell scratch assay and Transwell assay were used to detect the effect of cinbufagin on the migration and invasive ability of HCT116 cells;Western blot was used to detect the expression levels of janus kinase 2(JAK2)/signal transducers and activators of transcription 3(STAT3)pathway and EMT-related proteins of HCT116 cells.Results The number of clone formation in blank group and experimental-L,-M,-H groups were 122.67±24.42,73.67±15.82,44.33±4.51 and 21.67±1.53;the rates of migration of scratches were(44.64±9.15)％,(26.91±2.94)％,(19.28±1.52)％and(6.33±2.30)％;the number of invaded cells were 120.33±1.15,58.33±9.07,33.33±1.53 and 18.33±3.21;the relative protein expression of phosphorylated JAK-2(p-JAK-2)/JAK-2 were 1.02±0.06,0.94±0.05,0.75±0.22 and 0.49±0.22;relative protein expression of phosphorylated STAT3(p-STAT3)/STAT3 were 0.89±0.10,0.72±0.04,0.65±0.06 and 0.52±0.18;relative protein expression of E-cadherin were 0.30±0.14,0.41±0.13,0.49±0.14 and 0.69±0.17;relative protein expression of N-cadherin were 0.96±0.11,0.78±0.04,0.69±0.12 and 0.40±0.15;Snail relative protein expression were 0.89±0.08,0.62±0.15,0.44±0.15 and 0.27±0.09;Vimentin relative protein expression were 0.92±0.09,0.76±0.13,0.63±0.01 and 0.43±0.09,respectively.The above indexes in experimental-H group showed statistically significant differences compared to blank group(all P＜0.05).Conclusion HCT116 can inhibit the invasion and metastasis of human colorectal cancer cells HCT116 by inhibiting epithelial-mesenchymal transition through JAK2/STAT3 pathway.

Objective To explore the mechanism of inhibition of colorectal cancer cells HT29 proliferation,migration and invasion by bufalin through Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)pathway.Methods Human colorectal cancer HT29 cells were randomly divided into control group and experimental-L,-M,-H groups.The cells in the control group were not treated,and the cells in the experimental-L,-M,-H groups were treated with 2.5,5.0 and 10.0 μmol·L-1 bufalin for 48 h.After HT29 cells were infected with FLAG STAT3 lentivirus,the cells were divided into lentivirus infection group and experiment-H(10.0 pmol·L-1 bufalin)+lentivirus infection group.Cell viability was detected by cell counting kit 8(CCK-8).Cloning experiment to verify cell proliferation rate;Transwell experiment verified the migration ability of cells after bufalin treatment;the transfection efficiency of lentivirus and the expression of cell-related proteins were detected by Western blot.Results After 48 h of drug action,the number of cells in the control group,experimental-L,-M,-H groups were 1 003.25±255.53,698.00±152.25,562.13±31.56 and 449.50±82.40,respectively;the number of invasive cells were 932.00±188.84,742.22±108.64,514.67±124.82 and 343.56±86.42,respectively;the protein expression level of p-JAK2 were 1.37±0.27,0.97±0.06,0.74±0.06 and 0.39±0.12,respectively.The number of cells in the control group,experimental-H group,lentivirus infection group,and experimental-H+lentivirus infection group were 906.88±211.71,389.00±143.08,1 279.38±210.34 and 604.75±12.52,respectively;the number of invasive cells were 671.22±44.74,246.11±28.16,1 080.78±119.13 and 574.78±16.23,respectively.Compared with the control group,there were statistically significant differences in the number of cell proliferation,the number of cell invasion and the relative levels of p-JAK2 in the experimental-M and-H groups(all P＜0.05).Compared with the control group,the number of cell proliferation and the number of cell invasion in the experimental-H group,the lentivirus infection group,and the high-dose experimental+lentivirus infection group were statistically significant(all P＜0.05).Conclusion Bufalin can inhibit the proliferation,migration and invasion of colorectal cancer by activating the JAK2/STAT3 signalling pathway.

Objective To explore the role of endothelial cells in angiogenesis and myocardial remodeling in heart failure based on MAPKs pathway mediated by tumor endothelial marker 1(TEM1).Methods Sixty-four mice were equally randomized into four groups:sham operation,myocardial infarction(MI),MI+sh-NC and MI+ sh-TEM1.On the 7th day after MI,the changes of EndMT in the infarct border area were detected by immunofluo-rescence staining,and the cardiac function of mice was evaluated by echocardiography on the 28th day.Mouse aortic endothelial cells(MAECs)were divided into three groups:control,Vector and rTEM1.In addition,MAECs were pretreated with MAPK inhibitor SB203580,and the cells were treated with rTEM1 for 48 h.The changes of EndMT and MAPKs signaling pathways in endothelial cells were evaluated by Western blot.Results In the myocardium at the border of infarction,the level of TEM1-1 increased slightly on the 1st day after MI,reached the peak on the 7th day,and then decreased on the 28th day.Compared with Vector group,the expression of VE-Cadherin protein in the rTEM1 group decreased significantly(P<0.05),and the levels of α-SMA and vimentin,relative migration distance,the number of invading cells,and the number of branching formation increased signifi-cantly(P<0.05).SB203580 reversed these changes of MAECs induced by rTEM1.Compared with the MI group,the co-staining level of CD31+Vimentin+ in the MI+sh-TEM1 group decreased significantly(P<0.01).On the 28th day,the LVEF and LVFS in the MI+sh-TEM1 group were significantly higher than those in MI group(P<0.05).Compared with the MI group,the expressions of p-P38/P38 and p-JNK/JNK in the endothelial cells of the MI+sh-TEM1 group decreased.Conclusion EndMT and angiogenesis induced by TEM1 participate in the pathogenesis of cardiac fibroblasts induced by MI,which may be mechanically related to the activation of MAPKs signaling pathway.

BACKGROUND:In recent years,with the development of biological scaffold materials and bioprinting technology,tissue-engineered bone has become a research hotspot in bone defect repair. OBJECTIVE:To summarize the current treatment methods for bone defects,summarize the biomaterials and bioprinting technology for preparing tissue-engineered bone scaffolds,and explore the application of biomaterials and printing technology in tissue engineering and the current challenges. METHODS:Search terms were"bone defect,tissue engineering,biomaterials,3D printing technology,4D printing technology,bioprinting,biological scaffold,bone repair"in Chinese and English.Relevant documents published from January 1,2009 to December 1,2022 were retrieved on CNKI,PubMed and Web of Science databases.After being screened by the first author,high-quality references were added.A total of 93 articles were included for review. RESULTS AND CONCLUSION:The main treatment methods for bone defects include bone transplantation,membrane-guided regeneration,gene therapy,bone tissue engineering,etc.The best treatment method is still uncertain.Bone tissue engineering technology is a new technology for the treatment of bone defects.It has become the focus of current research by constructing three-dimensional structures that can promote the proliferation and differentiation of osteoblasts and enhance the ability of bone formation.Biological scaffold materials are diverse,with their characteristics,advantages and disadvantages.A single biological material cannot meet the demand for tissue-engineered bone for the scaffold.Usually,multiple materials are combined to complement each other,which is to meet the demand for mechanical properties while taking into account the biological properties of the scaffold.Bioprinting technology can adjust the pore of the scaffold,build a complex spatial structure,and is more conducive to cell adhesion,proliferation and differentiation.The emerging 4D printing technology introduces"time"as the fourth dimension to make the prepared scaffold dynamic.With the synchronous development of smart materials,4D printing technology provides the possibility of efficient repair of bone defects in the future.

【Objective】 To explore the feasibility of using autologous platelet-rich plasma (PRP) in the treatment of deep second-degree burns complicated with wound infection. 【Methods】 A retrospective analysis was conducted on the treatment process of a patient with deep second-degree burns and bacterial infection on the wound using autologous PRP. Clinical treatment highlights and outpatient follow-up were combined to discuss the feasibility and clinical effects of using autologous PRP in the treatment of burn wounds complicated with infection. 【Results】 The patient had a deep second-degree burn with a coagulase-negative Staphylococcus infection on the left lower limb. After one week of conventional wound dressing and antibiotic treatment, the patient's body temperature returned to normal. However, wound healing was slow and yellow secretion persisted. Subsequently, the burn wound was treated combined with topical autologous PRP. The wound pain score gradually decreased from 8 to 1. After 2 weeks, the bacterial culture of the wound secretion was negative, and the wound healed completely after 18 days. The wound scar score decreased from 5 to 2 at 1, 3 and 6 months after PRP treatment, and no obvious scar formation was observed. In the course of PRP treatment, there were no adverse reactions such as increased wound inflammation, abnormal blood routine and liver and kidney function test results. 【Conclusion】 For deep second-degree burn patients with localized wound bacterial infections who either refuse surgery or are not suitable for surgery, autologous PRP is a safer alternative that can effectively promote tissue regeneration and wound healing. The patient in this case achieved a curative effect in a short period of time.

ObjectiveDetection and quantification of RNA synthesis in cells is a widely used technique for monitoring cell viability, health, and metabolic rate.After exposure to environmental stimuli, both the internal reference gene and target gene would be degraded. As a result, it is imperative to consider the accurate capture of nascent RNA and the detection of transcriptional levels of RNA following environmental stimulation. This study aims to create a Click Chemistry method that utilizes its property to capture nascent RNA from total RNA that was stimulated by the environment. MethodsThe new RNA was labeled with 5-ethyluridine (5-EU) instead of uracil, and the azido-biotin medium ligand was connected to the magnetic sphere using a combination of “Click Chemistry” and magnetic bead screening. Then the new RNA was captured and the transcription rate of 16S rRNA was detected by fluorescence molecular beacon (M.B.) and quantitative reverse transcription PCR (qRT-PCR). ResultsThe bacterial nascent RNA captured by “Click Chemistry” screening can be used as a reverse transcription template to form cDNA. Combined with the fluorescent molecular beacon M.B.1, the synthesis rate of rRNA at 37℃ is 1.2 times higher than that at 15℃. The 16S rRNA gene and cspI gene can be detected by fluorescent quantitative PCR,it was found that the measured relative gene expression changes were significantly enhanced at 25℃ and 16℃ when analyzed with nascent RNA rather than total RNA, enabling accurate detection of RNA transcription rates. ConclusionCompared to other article reported experimental methods that utilize screening magnetic columns, the technical scheme employed in this study is more suitable for bacteria, and the operation steps are simple and easy to implement, making it an effective RNA capture method for researchers.