ABSTRACT
Objective:To comprehensively evaluate the tricuspid valve, right heart anatomical characteristics and related dynamic parameters in patients with different degrees of functional tricuspid regurgitation (FTR) using four-dimensional auto tricuspid valve quantitative(4D Auto TVQ), four-dimensional auto right ventricle quantitative(4D Auto RVQ), and four-dimensional auto left atrium quantitative(4D Auto LAQ), and to investigate the structural and functional changes of the tricuspid valve and right heart in them.Methods:Sixty-three patients with FTR diagnosed by echocardiography at the First Affiliated Hospital of Guangxi Medical University from February to July 2022 were prospectively selected as the case group, including 30 patients with mild FTR and 33 patients with moderate or above FTR, and 30 healthy subjects were selected as the control group. Transthoracic echocardiography was used for two-dimensional and three-dimensional image acquisition of the heart. The tricuspid regurgitation volume, left ventricular ejection fraction (LVEF), right ventricular global strain (RVGS) were measured by 2D images, and pulmonary artery systolic pressure (PASP) were measured from the tricuspid regurgitation pressure difference. The 3D images were imported into EchoPAC 204 to obtain the tricuspid valve, right heart structure and related dynamic parameters. The annulus area (AA), annulus perimeter(AP), spherical index (SI), annulus area change fraction (AC), coaptation point height (CPH), and tenting volume (TV) were measured by 4D Auto TVQ. The right atrial maximum volume (RAVmax) and right atrial minimum volume (RAVmin) were measured by 4D Auto LAQ. Right ventricular end-diastolic volume (RVEDV), right ventricular end-systolic volume (RVESV), right ventricular fractional area change (RVFAC) and tricuspid annular plane systolic excursion (TAPSE) were measured by 4D Auto RVQ. After standardizing the dimension parameters with body surface area (BSA), the differences in the above parameters were compared between the three groups, the correlation between regurgitant volume and each parameter was compared by correlation analysis, and the independent factors of increased tricuspid regurgitant volume were investigated by univariate and multivariate linear regression analysis.Results:There were statistically significant differences in PASP, AA/BSA, AP/BSA, AC, TV, RAVmax/BSA, RAVmin/BSA, RVFAC, RVGS, and TAPSE between the three groups (all P<0.05). There were statistically significant differences in LVEF, CPH, RVEDV/BSA, and RVESV/BSA in the moderate and above FTR group compared with the control and mild FTR groups (all P<0.05). Correlation analysis showed that RAVmin was the most highly correlated with tricuspid regurgitant volume ( r=0.875, P<0.001) and TV and end-systolic annulus area(ESAA) were highly correlated with tricuspid regurgitant volume ( r=0.747, 0.683; both P<0.001) in patients with FTR. Multifactorial linear regression showed that RAVmin, TV and regurgitant volume were independently positively correlated (β=0.721, 0.205; both P<0.05). Conclusions:The four quantification technique can provide valid structural and functional information by quantifying the tricuspid valve as well as the right heart in patients with FTR, and RAVmin and TV are independent correlates of increased tricuspid regurgitant volume.
ABSTRACT
Objective:To evaluate the effect of acupuncture of Zhukeyuanluo principle and Buzhong Yiqi Decoction on obstructive sleep apnea hypopnea syndrome (OSAHS).Methods:Randomized controlled trial. A total of 104 patients with OSAHS in our hospital from January 2017 to January 2022 who met the inclusion criteria were divided into 2 groups according to random number table method, with 52 patients in each group. The Traditional Chinese Medicine (TCM) group was treated with Buzhong Yiqi Decoction on the basis of conventional western medicine treatment, and the acupuncture and medicine group was treated with the combination of primary and primary collaterals and acupoints. Both groups were treated continuously for 2 months. Epworth Lethargy Scale and Stanford Self-Rated Lethargy Scale (SSS) were used to assess the degree of lethargy. The serum levels of TNF-α, IL-6 and IL-8 were detected by ELISA. The hemoglobin, RBC and mean RBC volume levels were detected by automatic blood cell analyzer. apnea hypopnea index (AHI), apnea index (AI), hypopnea index (HI) and arterial oxygen saturation (SaO 2) were monitored by polysomnographic sleep monitor to evaluate the clinical effect. Results:The total effective rate was 94.2% (49/52) in the acupuncture group and 82.7% (43/52) in the TCM group, and there was significant difference between the two groups ( χ2=6.73, P=0.035). After treatment, the Epworth Lethargy Scale and SSS scores in the acupuncture and medicine group were significantly lower than those in the TCM group ( t=-8.19 and -5.48, respectively, P<0.01); AHI [(15.64±2.81) times/h vs. (19.82±3.05) times/h, t=-7.27], HI [(5.53±1.28) times/h vs. (7.37±1.34) times/h, t=-7.16], AI [(8.13±1.95) times/h vs. (10.98±2.26) times/h, t=-6.89] in the acupuncture and medicine group were significantly lower than those in the TCM group ( P<0.01), SaO 2 [(92.77±2.91) % vs. (89.53±2.44) %, t=6.15] in the acupuncture and medicine group was significantly higher than that of the TCM group ( P<0.01). The levels of TNF-α, IL-6 and IL-8 in serum in the acupuncture and medicine group were significantly lower than those in the TCM group ( t=-2.62, -3.14 and -6.58, P<0.01). The levels of hemoglobin, RBC and mean red blood cell volume were in the acupuncture and medicine group were significantly lower than those in the TCM group ( t=-2.11, -2.92, -2.48, P<0.05 or P<0.01). Conclusion:The acupuncture of Zhukeyuanluo principle combined with Buzhong Yiqi Decoction can reduce the serum inflammatory cytokines level in OSAHS patients, increase SaO 2, reduce AHI, HI, AI and lethargy degree, and improve clinical effects.
ABSTRACT
Macropinocytosis, an evolutionarily conserved, actin-dependent form of endocytosis, is involved in various physiological processes, including nutrient absorption, antigen presentation, and cell signaling transduction and migration. Oncogene activation and tumor suppressor inactivation induce macropinocytosis in tumors in the digestive system, involved in tumorigenesis and progression, whereas the inhibition of macropinocytosis slows the aggressive phenotype of digestive system tumors and improves the efficacy of anti-tumor drugs. Macropinocytosis can also be used as a delivery route for anti-tumor drugs. Therefore, macropinocytosis has been widely studied to develop new methods for the treatment of digestive system tumors.This paper reviews the role of macropinocytosis in the body, the regulation of macropinocytosis-related signaling pathway, as well as the mechanism of macropinocytosis in colorectal cancer, pancreatic ductal adenocarcinoma, liver cancer and other digestive system tumors, to provide reference for related researches.
ABSTRACT
Objective To investigate the effect of Yipi Yanggan prescription on the malignant transformation of liver stem cells in liver precancerous lesion induced by diethylnitrosamine (DEN) and its possible molecular mechanism. Methods A total of 35 male Sprague-Dawley rats were randomly divided into normal control group (blank group), DEN model group (model group), DEN+Yipi Yanggan prescription group (Yipi Yanggan prescription group), and DEN+Hugan tablet group (Hugan tablet group), with 5 rats in the blank group and 10 rats in the other three groups. Intraperitoneal injection of DEN was performed to establish a model of liver precancerous lesion, the rats were sacrificed after 16 weeks of administration. The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and albumin (Alb) were measured; liver tissue was collected to observe the changes in size and appearance and calculate liver weight ratio (liver index); HE staining and Sirius Red staining were used to observe the pathological and morphological changes of rat liver tissue; immunohistochemistry was used to measure the expression of OV6 and glutathione S-transferase-Pi (GST-Pi); RT-PCR was used to measure the mRNA expression of EpCAM, CD133, and CD90, and Western blot was used to measure the protein expression of PI3K, Akt, and mTOR and their phosphorylation level. A one-way analysis of variance was used for comparison between multiple groups, and the least significant difference t -test was used for further comparison between two groups. Results Compared with the model group, the Yipi Yanggan prescription group and the Hugan tablet group had significant improvements in liver pathology and morphology, significant reductions in liver index and the levels of ALT and AST, and a significant increase in the level of Alb (all P < 0.05), as well as significant reductions in the protein expression levels of GST-Pi, OV6, p-PI3K, p-Akt, and p-mTOR and the mRNA expression levels of EpCAM, CD133, and CD90 (all P < 0.05). Compared with the Hugan tablet group, the Yipi Yanggan prescription group showed a more significant protective effect on the liver, with significant reductions in liver index and the levels of ALT and AST, and a significant increase in the level of Alb (all P < 0.05), as well as significant reductions in the protein expression levels of GST-Pi, OV6, p-PI3K, p-Akt, and p-mTOR and the mRNA expression levels of EpCAM, CD133, and CD90 (all P < 0.05). Conclusion Yipi Yanggan prescription can improve liver precancerous lesion induced by DEN in rats by inhibiting the malignant transformation of liver stem cells, and its mechanism of action may be associated with the PI3K/Akt/mTOR signaling pathway.
ABSTRACT
Hepatocellular carcinoma (HCC) is the most common pathological type of primary liver cancer, with high fatality rate. The pathogenesis of HCC is complex, and the specific occurrence and development mechanism is still in the exploratory stage. CircRNA is a special endogenous noncoding RNA and mainly participates in the regulation of gene expression at the transcriptional and posttranscriptional levels. By regulating gene transcription, it acts as a molecular sponge of miRNA, participates in protein translation, and interacts with RNA binding protein (RBP). CircRNA is involved in the occurrence and development of HCC. Its abnormal expression in HCC cells is related to the pathological characteristics of HCC tissue, regulates the expression of downstream target genes, miRNA and proteins, participates in the proliferation, migration, invasion and apoptosis of HCC cells, and regulates tumor microenvironment and signal pathways, suggesting that circRNA may be a potential novel biomarker and therapeutic target for the diagnosis and prognosis of HCC. This paper reviews the biological mechanism of circRNA, its role in HCC, and research progress in diagnosis and treatment.
ABSTRACT
Objective:To compare the teaching effect of flipped classroom approach versus traditional lecture-based approach on the laboratory training course of Orthodontics cephalometric analysis for dental undergraduates. Methods:A total of 60 dental undergraduates who participated in the undergraduate course of Orthodontics were included in the study and randomly divided into experimental group and control group, with 30 students in each group. Flipped classroom approach was performed in the experimental group, while traditional lecture-based approach was used in the control group. Students' recognition towards teaching excellence, theoretical and laboratory performances, and their understanding and application of the key points in orthodontic cephalometric analysis were evaluated. SPSS 22.0 was used for t test and chi-square test. Results:Compared with the control group, students in experimental group gave more favorable rating in learning experience, had better learning motivation and more confidence in understanding and mastering the key points of orthodontic cephalometric analysis, with significant differences ( P<0.05). Besides, they also presented better theoretical and laboratory performances and superior mastery of the key points in the post-class quiz, with significant differences ( P<0.05). Conclusion:Flipped classroom is a promising approach to improve the teaching effect of cephalometric analysis of Orthodontics.
ABSTRACT
Autophagy can regulate liver physiology and balance liver metabolism. Autophagy activation has a double-sided and complex effect on liver injury, and it is regulated by many factors and is associated with many protein pathways. This article summarizes the role of mTOR in the regulation of autophagy, which can inhibit or enhance autophagy through the PI3K/Akt upstream signaling pathway and participate in the physiological and pathological changes of related liver diseases. Therefore, this article reviews the research advances in the mTOR/PI3K/Akt autophagy pathway in liver injury, in order to provide new therapeutic targets for related liver diseases.
ABSTRACT
Excessive lipid deposition, liver injury, and insulin resistance are hallmarks in the development and progression of nonalcoholic fatty liver disease (NAFLD). Liver X receptor (LXR) is a transcriptional regulator, and its two cell subtypes, LXRα and LXRβ, play a key role in regulating cholesterol metabolism, inducing anti-inflammation, and reducing insulin resistance. This article reviews the structure and function of LXR and its association with the pathogenesis of NAFLD, in order to provide new ideas and methods for the prevention and treatment of NAFLD.
ABSTRACT
The development and progression of liver cancer have the stages of hepatitis, liver cirrhosis, precancerous lesion, and liver cancer, among which the malignant transformation of precancerous lesions of liver cancer is closely associated with the activation of hepatic stellate cells (HSC). By describing the activation of HSC, the generation of precancerous cells of liver cancer, the formation of inflammatory fibrotic microenvironment, and the association between HSC activation and precancerous lesion, this article points out that microRNAs can affect the malignant transformation of precancerous lesion of liver cancer by regulating the expression of related target genes and HSC activation, and the research in this field is expected to provide new ideas and targets for the prevention and treatment of liver cancer.
ABSTRACT
Ulcerative colitis is an intestinal inflammatory disease characterized by diarrhea, abdominal pain and purulent stool. Uncontrolled inflammation caused by macrophage hyper-activation is an important cause of ulcerative colitis. Therefore, inhibiting macrophage hyper-activation is an effective way to treat ulcerative colitis. Notch signaling pathway is involved in regulating the immune response of macrophages and promoting inflammation. NF-κB signaling pathway is the "star pathway" involved in inflammation. NLRP3 inflammatory body is involved in the activation of macrophages. Notch, NF-κB and NLRP3 inflammatory bodies constitute the upstream and downstream signal pathways in the existing immune inflammatory diseases. Notch signal pathway can regulate the activation of macrophage via NF-κB/NLRP3 inflammatory body signaling pathway.
Subject(s)
Humans , Colitis, Ulcerative , Cytokines , Macrophage Activation , NF-kappa B , NLR Family, Pyrin Domain-Containing 3 Protein , Receptors, Notch , Signal TransductionABSTRACT
ObjectiveTo construct a protein interaction network based on high-throughput sequencing data of liver cancer-related non-coding RNAs, to perform a functional enrichment analysis, and to screen out circular RNAs (circRNAs) participating in the development and progression of liver cancer via the mechanism of competitive endogenous RNA (ceRNA). MethodsThe circRNA-miRNA-mRNA network was constructed using gene expression omnibus (GEO) data based on the ceRNA theory. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) analyses were performed to identify circRNAs with potential ceRNA function and explore their functions. ResultsA total of 9 co-expressed circRNAs, 20 co-expressed miRNAs, and 153 co-expressed mRNAs were screened out from the GEO database, and the liver cancer-related circRNA-miRNA-mRNA network was successfully constructed. The GO analysis revealed 90 biological processes, which mainly involved 12 functional clusters including hepatocyte differentiation, phase-change regulation of cell cycle, and negative regulation of transcription factor activity. The KEGG analysis showed that the co-expressed circRNAs were also involved in the p53 and PI3K-Akt signaling pathways. ConclusionThis study provides new insights for circRNAs mediating the development and progression of liver cancer through the mechanism of ceRNA.
ABSTRACT
Intrahepatic cholestasis (IHC) is a dysfunction of bile production, secretion, and excretion caused by various factors including genetics, immunity, inflammation, stones, and tumors, and therefore, the bile is not normally discharged into the duodenum and reversely flows into blood, which causes a series of clinical diseases with organic damage, metabolic disorders, and dysfunction. In recent years, with the deepening of clinical and basic research, intestinal microecology is found to play an important role in the development and progression of liver diseases. This article reviews the mechanism of action of intestinal microecology and inflammatory factors in intrahepatic cholestasis and explores the research advances in the role of probiotics in regulating intestinal flora stability and improving intestinal microenvironment, so as to provide a basis for clinical treatment, scientific research, and drug research and development.
ABSTRACT
Hepatic fibrosis is the process of fiber formation and inflammation caused by chronic liver injury, and is a common pathological process of hepatic cirrhosis and hepatic carcinoma. The prevention and treatment of liver fibrosis can effectively control the incidence of liver cirrhosis and liver cancer, but its pathogenesis remains unclear. Endoplasmic reticulum stress is a kind of subcellular organelle pathological process that causes the disruption of ion balance in endoplasmic reticulum or the obstacle of protein processing and transportation. In recent years, more and more studies have shown that endoplasmic reticulum stress is involved in the occurrence, development and reversal of liver fibrosis. This article reviews the regulatory role of endoplasmic reticulum stress in liver fibrosis.
ABSTRACT
Objective To explore the biomechanical mechanism of non-erosive reflux disease(NERD).MethodsFrom October 4,2014 to September 30,2015,17 NERD patients and 17 healthy controls were recruited from the outpatients department of China-Japan Friendship Hospital.The cross-sectional area(CSA), intra-balloon pressure (IBP)and compliance(Δv/Δp)of each were measured by endoscopy in combination with EndoFlip.ResultsWith the increase of balloon volume,the compliance of gastroesophageal junction in NERD group was significantly higher than that of control group(P<0.01) while the cross sectional area and intra-balloon pressure were similar.Conclusions Increased compliance of the gastroesophageal junction may be involved in the pathogenesis of non-erosive reflux disease.
ABSTRACT
Many studies have shown that Chinese herb extracts could treat patients who suffer hepatitis C. However, the clinical efficacy is limited due to the use of traditional Chinese medicine (TCM) compounds. Because each drug contains multiple active substances, some of which may even act against each other in vivo, it is hard to clarify the mechanism of treatment. The current research on pseudotyped hepatitis C virus (HCV), replicon, and cell culture system is summarized, and the advances in antiviral research on the monomers or active components of Chinese herbs in vitro based on HCV RNA models are reviewed, thus providing new ideas for TCM treatment of hepatitis C.
ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the effectiveness of hypnotic and musical relaxation therapy and psychological consultation for parents of children with cleft lip and/or palate (CLP) and to provide a scientific basis of clinical-psychological treatment options.</p><p><b>METHODS</b>Sixty-six subjects with children with CLP participated in this study. The subjects were randomly assigned to a test group (n = 33) and a control group (n = 33). The test group was treated with hypnotic and musical relaxation therapy; the control group were subjected to psychological consultation. Anxiety and depression states were evaluated by using a self-rating anxiety scale (SAS) and a self-rating depression scale (SDS) before and after treatment was administered.</p><p><b>RESULTS</b>1) The test group demonstrated a significant decrease in SAS and SDS scores (t = 2.855, P < 0.01; t = 2.777, P < 0.01). The control group showed a significant decrease in the SAS score (t = 1.831, P < 0.05) but failed to show a significant change in the depression score (t = 0.909, P > 0.05). 2) The test group yielded a higher percentage of remission indicated by the SDS scores than the control group (test group = 75.76%; control group = 60.61%; P < 0.05). The test group also displayed a higher percentage of remission indicated by the SAS scores than the control group (test group = 78.79%, test group = 69.70%; P < 0.05).</p><p><b>CONCLUSION</b>Hypnotic and musical relaxation therapy can more effectively reduce the scores of the anxiety and depression states of the parents of patients with cleft lip and/or palate than psychological consultation.</p>
Subject(s)
Child , Humans , Anxiety , Psychology , Therapeutics , Cleft Lip , Psychology , Cleft Palate , Psychology , Depression , Psychology , Therapeutics , Hypnosis , Music , Parents , Psychology , Relaxation Therapy , Methods , Self-AssessmentABSTRACT
Objective To evaluate endoscopic ultrasound for preoperative staging of ampullar tumors.Methods A total of 31 patients with ampullar tumors who underwent surgery from 2010 to 2015 were retrospectively reviewed.B-US,CT,MRCP and EUS were performed in all patients.The diagnostic rates of EUS and other imaging technology,and the diagnostic accuracy of preoperative staging and postoperative pathological staging were compared.Results Diagoses of 31 patients of ampullar tumors patients undergoing preoperative endoscopic ultrasonography assessment T staging were as the following:uT1,4 cases; uT2,15 cases; uT3,10 cases; uT4,2 cases.Compared with the postoperative pathological diagnosis,the T staging accuracy was 90.3％ (28/31),anong which 1 case was overestimated,2 cases were underestimated.The accuracy of endoscopic ultrasound in preoperative diagnosis of ampullar lesions was superior to other detection technology.Conclusion EUS is a valuable diagnostic tool for patients with suspected ampullar tumors.
ABSTRACT
Objective To explore the significance of treadmill exercise test (TET) in identifying left main coronary artery(LMD) obstruction from proximal left anterior descending(LAD) obstruction.Methods Patients with positive in the TET of the Central Hospital of Dalian from Jan.2008 to Dec.2013 were enrolled in this study and they were divided into LMD group with 21 cases and LAD group with 35 cases according to the results of coronary angiography.Retrospectively study was conducted to analyze the exercise time,the start time of ST segment change,the lead of ST segment between groups.Results Lead aVR ST segment elevation(≥0.10 mV) was 85.7％ (18/21) in the LMD group and 62.9％ (22/35) in the LAD group.Lead aVR ST segment elevation in the LM group was ((0.16 ± 0.07) mV,higher than in the LAD group ((0.11 ± 0.07) mV ; t =2.614,P ＜ 0.05).Accompany ST segment depression of leads and cumulative ST segment depression were (5.7 ±1.7) pcs and (1.13 ±0.42) mV in LMD group,significantly higher than those of LAD group((4.6 ± ± 1.8) pcs and (0.87 ± 0.32) mV ; t =2.314,2.634,P ＜ 0.05).The occurrence rate of ST segment depression (≥0.10 mV) in leads V2 and V6 were 33.3％ (7/21) and 90.5％ (19/21) in LM group,significantly higher than that in LAD group (11.4％ (4/35) and 62.9 ％ (22/35) ; x2 =3.990,5.105 ;P ＜ 0..05).The start time of ST segment deviation of LM group was significantly earlier than that of LAD group ((199.8 ± 70.8) s vs.(273.7 ± 127.3) s;t =-2.787,P ＜ 0.01).The differences were not statistically significant in terms of the exercise time between groups ((315.0 ± 120.0) s vs.(376.1 ± 110.0) s;t =-1.948;P ＞ 0.05),the rate for achieving target heart rate(33.3％ (7/21) vs.48.6％ (17/35) ; x2 =1.244 ; P ＞ 0.05) and the Duke score ((-11.8 ±7.2) vs.(-8.4 ±6.8) ;t =-1:772;P＞0.05).Conclusion Compare with patients with the LAD disease,ST segment elevation of lead aVR is significantly higher induced by treadmill exercise test in patients with left main disease.Meanwhile,the lead accompanied with ST segment depression is significantly higher,and the start time of ST segment deviation is significantly earlier.
ABSTRACT
Objective To observe the influence of pulse pressure on renal injury in patients with essential hypertension (EH).Methods Two hundred and twenty-nine patients with mild-to-moderate EH completed 24 h ambulatory blood pressure monitoring.The patients were divided into 2 groups according to 24 h mean pulse pressure (MPP):EH 1 (24 h MPP ≥ 60 mmHg,1 mmHg =0.133 kPa) group (128 cases) and EH2 (24 h MPP ＜ 60 mmHg) group (101 cases).According to 24 h urine microalbumin and biochemical determination of renal function,the influence of pulse pressure on kidney function was observed and compared.Results The 24 h mean systolic blood pressure (MSBP) and 24 h MPP in EH1 group were significantly higher than those in EH2 group [(156.20 ±6.11) mmHg vs.(143.67 ±5.46) mmHg,(69.09 ±5.87) mmHg vs.(51.15 ±7.15) mmHg] (P ＜0.01),the 24 h mean diastolic blood pressure (MDBP) in EH2 group was significantly higher than that in EH1 group [(92.52 ±5.93) mmHg vs.(87.11 ± 5.52) mmHg](P＜ 0.01).The 24 h urine microalbumin in EH1 group was significantly higher than that in EH2 group [(104.80 ± 24.25) mg vs.(91.29 ± 24.03) mg] (P ＜ 0.01).There was positive correlation between 24 h MPP,24 h MSBP and 24 h urine microalbumin (r =0.259,0.201,P ＜ 0.01),and there was negative correlation between 24 h MDBP and 24 h urine microalbumin (r =-0.180,P＜ 0.01).Conclusion The 24 h MPP is closely related with the renal injury which is caused by high blood pressure in patients with EH.
ABSTRACT
<p><b>OBJECTIVE</b>To construct the recombinant HCV-1b replicon by replacing NS5A region using serum samples from patients with chronic hepatitis C (CHC) in South China and explore the biological characteristics of NS5A protein in response to antiviral therapy.</p><p><b>METHODS</b>The on-off plasmid containing the cutting sites of the restriction endonucleases MIu I and Bcl I was designed based on the backbone of robust HCV 1b replicon. The full-length fragments of HCV NS5A were amplified from different CHC patients by RT-PCR and cloned into pMD-18 vector, followed by sequence analysis of amino acid mutation of ISDR, PKRBD, V3 and IRRDR within the NS5A region. If the amplicon obtained contained no MIu I or Bcl I cutting sites, the NS5A fragment was re-amplified using primers containing the cutting sites and inserted into the replicon for replacement.</p><p><b>RESULTS</b>The full-length fragments of NS5A were obtained successfully from CHC patients. The core region of ISDR-V3 of NS5A was replaced in the HCV replicon plasmid and showed correct sequences. The amino acid mutations of ISDR and PKRBD within NS5A were more frequent in patients with sustained viral response (SVR) than those without SVR. A high variability in the amino acid sequence was observed in both IRRDR and V3 regions.</p><p><b>CONCLUSION</b>The plug-in type recombinant HCV replicon for replacement of NS5A region in the virus from CHC patients has been successfully constructed, which provides a basis for further investigation of the biological characteristics of NS5A protein, the mechanisms of interferon-resistance, and antiviral therapy of difficult-to-treat CHC.</p>