AIM: To observe the effects of high-dose hepatitis B surface antigen (HBsAg) vaccine on cellular immune response in BALB/C mice. METHODS: The mice were immunilized separately with low-dose and high-dose HBsAg vaccine by intramuscular injection two times. The specific proliferative activities of T lymphocytes were measured by [ 3H]-TdR incorporation assay. IL-2 as well as IFN-? levels in the culture supernatant of T cells and anti-HBs IgG2a lever in sera were detected by enzyme-linked immunoabsorbent assay. RESULTS: After first vaccination with high-dose HBsAg, the proliferative activities of T cells in the experimental group were significantly stronger, both levels of IL-2 and IFN-? were markedly higher than that in the control group and the percentage of mice to produce serum anti-HBs IgG2a was significantly higher compared to that of mice immunilized by low-dose HBsAg. All data in experimental groups were further increased after second dose of vaccine. CONCLUSION: Vaccination of mice with high-dose HBsAg can induce cellular immune responses tended to Th1(T helper 1 subset) response.

Objective: To screen candidate antigen for therapeutic HBV vaccine with a novel adjuvant DC-Chol. Methods: BALB/c mice were injected with DC-Chol liposome and HBsAg prepared from CHO and Yeast respectively. One week later, IL-4, IL-2, IFN-?were measured by ELISA or ELISPOT. Results: The levels of IL-2, IFN-?of HBsAg from Yeast with DC-Chol liposome were 20 and 119 times higher respectively than those of HBsAg from CHO with DC-Chol liposome. ELISPOT assay showed that the counts of spot-forming cells of IL-4 and IFN-?of HBsAg from Yeast with DC-Chol liposome were 2.8 and 46.3 times higher respectively than those of HBsAg from Yeast with Al(OH)3. Conclusion: HBsAg prepared from Yeast together with DC-Chol liposome may be an appropriate candidate for therapeutic HBV vaccine .

Abstract: Objective　To analyze the nucleic acid detection results of severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) by droplet digital PCR (ddPCR) and compare with the detection results of real-time fluorescence quantitative RT-PCR (qRT-PCR), so as to evaluate the advantages and disadvantages of detection, and to provide data support for optimizing the nucleic acid detection scheme of SARS-CoV-2. Methods　According to the SARS-CoV-2 specific primer probe published by the China Center for Disease Control and Prevention, a ddPCR detection method for SARS-CoV-2 was designed. One sample was selected for sensitivity test after gradient dilution; six respiratory virus nucleic acid positive samples including seasonal H3N2 influenza virus and SARS-CoV-2 positive samples were selected for specificity test; five SARS-CoV-2 positive samples were selected for repeatability test; in addition, 30 positive and 20 negative SARS-CoV-2 samples were selected for multiple clinical samples testing, and the results were analyzed and compared with those of qRT-PCR. Results　The ddPCR method can specifically detect SARS-CoV-2, and directly obtain the original copy number of the sample target gene to achieve accurate quantification; the sensitivity test of gradient dilution positive samples showed that qRT-PCR detected target genes in part of the 10-5 dilution of samples, and no target genes were detected in 10-6 dilution, while ddPCR detected all target genes in both 10-5 and 10-6 dilution of samples. The detection limit of ddPCR was two orders of magnitude higher than that of qRT-PCR, and the sensitivity was higher than that of qRT-PCR; in the comparison of the repeatability test results of the two methods, the coefficient of variation of ddPCR was 1.266%-11.814%, lower than 1.729%-26.174% of qRT PCR, and the repeatability was higher than qRT-PCR; among 50 clinical samples, 30 positive samples of confirmed cases of Coronavirus Disease 2019 (COVID-19) were detected by both methods, SARS-CoV-2 was successfully detected by both methods, and 20 negative samples of COVID-19 were detected by both methods, and the results were negative, with a coincidence rate of 100.00% (50/50). Conclusion　The ddPCR method can accurately quantify SARS-CoV-2 with strong specificity, and its sensitivity and repeatability are higher than those of qRT-PCR, but it also has certain detection limitations and is more suitable for the detection of low load samples. In the actual detection, the two methods can be reasonably combined to improve the detection accuracy.

Objective To establish a three-dimensional (3D) model of the diaphragm type of Budd-Chiari syndrome (BCS) with perforated membrane,to analyze changes of hemodynamic parameters pre and post percutaneous transluminal angioplasty (PTA) and to analyze any possibly related mechanical factors for postoperative recurrence in BCS.Methods The data on enhanced MRI from patients suffering from BCS with perforated diaphragm of inferior vena cava were reconstructed into a 3D model Computational fluid dynamics (CFD) were applied for numerical simulation based on the model,and the results were expressed as cloud images.Results The total number of model units of the finite element model for preoperative inferior vena cava stenosis was 16 422,and the total number of nodes was 48 170.The total number of model units for postoperative inferior vena cava was 16 539,and the total number of nodes was 51 339.Hemodynamic patterns of the lesion areas were effectively reflected in the 3D flow dynamic model for BCS.By comparing the hemodynamic parameters before and after interventional therapy,the data indicated that there was a gradual decline in wall pressure from the telecentric side.The largest blood flow velocity as well as wall shear stress were observed in the stenotic area of inferior vena cava.Both a large postoperative vascular central velocity and a low increase in local pressure predicted occurrence of vascular restenosis.Conclusions The establishment of a 3D fluid model of inferior vena cava revealed that there were mechanical changes in the location of the lesion.Variations in blood flow patterns exert a far-reaching influence on distribution of hemodynamic parameters,including local blood flow velocity,vascular wall pressure and shear stress.All these might be related to recurrence of BCS after interventional therapy.

Objective To explore the clinical application of 3D-printing model in guiding interventional management of Budd-Chiari syndrome (BCS) and in teaching practice.Methods A patient with typical BCS of inferior vena cava type was selected.By using MR enhanced scanning,the original MRA data of DICOM format were extracted,and then the digital data were extracted and reconstructed to obtain 3D BCS model by Simpleware software.The 3D BCS entity model,using 1 ∶ 1 ratio,was printed out by a 3D printer.An experienced chief physician made a simulated interventional manipulation on this 3D BCS entity model.Results The BCS 3D model was successfully printed.Simulated operation could be easily performed on the 3D-printing model,in this way the chief physician could make a demonstration of interventional procedure of BCS to the junior doctors and medical students.Interventional therapeutic manipulation for BCS could be well demonstrated on the 3D-printing model of BCS,which was very helpful in guiding teaching practice and in promoting the communication between doctors and patients.Conclusion The BCS 3D-printing model can truly reflect the spatial architecture features of the inferior vena cava and the hepatic veins,which are very valuable for the making of surgical plan,for the demonstration of simulation operation,and for teaching practice.Moreover,3D-printing model can stereoscopically display the location and morphology of the lesion,which can improve patient's understanding of the disease,thus,the communication between doctors and patients can be strengthened.

We have constructed an immunotoxin(Ng76-TCS),which was composed of a monoclonalantibody directed against human melanoma and trichosanthin(TCS)——a single chain ribosomeinactivating protein.The cultured human melanoma cells(M21)were inhibited effectively byNg 76-TCS.The cytotoxicity of Ng76-TCS to M21 cells was 2,000-fold higher than that of free TCS and Ng76 mixture.A conjugate,which was prepared with normal mice immunoglobulinand TCS(NIgG-TCS),was 160-fold less cytotoxic to M21 cells.Meanwhile Ng76-TCS was125-fold less cytotoxic to nontarget cells Hela.These results showed that the immunotoxinNg76-TCS was a potent and specific anti-human melanoma agent.

Objective To evaluate the expression of Toll-like receptor(TLR)on the monocyte- derived dendritic cells(DC)from chronic hepatitis B(CHB)patients and to analyze the expression pro- file and significance of the TLR such as TLR3,TLR4,TLR?,TLR8 and TLRg,which are associat- ed with immune response to viral infection.Methods Peripheral blood mononuclear cell(PBMC) centrifugated by the hydroxyethyl starch(HES)centrifugation were cultured and induced into DC by granulocyte-maerophage colony stimulating factor(GM-CSF)and interleukin-4(IL-4),and their mor- phology and phenotype were detected by the inverted microscope and flow cytometry respectively. Monocyte-derived DC were obtained from 10 chronically hepatitis B virus(HBV)-infected patients and 15 healthy volunteers.TLR3,TLR4,TLR7,TLRS,TLR9 expression on immature and mature DC were analyzed by FACS Calibur.DC was pulsed with HBcAg on day 3 and 5,then DC maturation and ability to process HBcAg and to stimulate autogeneic T cells were evaluated.Results Monocyte- derived DC developed different TLR expression patterns as they went through different maturation stages.TLR7,TLR8 expressions on immature DC and TLR3,TLR7 expressions on mature DC were lower in CHB than in control(for TLR7,TLR8 expression on immature DC:75.9%,1.0%vs 98.4%,15.4%,P

Objective To study the expression of vascular endothelial growth factor(VEGF)-C, VEGF-D and their receptor-3(VEGFR-3)in patients with colorectal cancer and their clinicopathological value.Methods Eighty specimens of the colorectal cancer and thirty normal adjacent bowels were stud- ied.The expression of VEGF-C,VEGF-D and VEGFR-3 proteins and mRNAs in specimens of colorectal cancers and normal colorectal tissues was studied by Strept-avidin-biotin complex method and RT-PCR. Clinicopathological data and survival of each patient were recorded and analyzed.Results①The staining of brown or filemot in cytoplast were observed as the positive expression of VEGF-C,VEGF-D and VEGFR-3 proteins.The positive rate(48.8%,56.3%,38.8%)and mean value(1.09?1.20,1.13?1.09,0.90?1.19)of VEGF-C,VEGF-D,VEGFR-3 expressions in specimens of colorectal cancer were significantly higher than those of the normal bowel tissues(P＜0.05).The expression of VEGF- C,VEGF-D and VEGFR-3 mRNAs by RT-PCR was correlated with that of VEGF-C,VEGF-D and VEGFR-3 proteins in colorectal carcinomas and normal bowel tissues.②Significant correlation between VEGF-C(P=0.0069),VEGF-D(P=0.0024)and VEGFR-3 expression was observed in colorectal cancers;moreover,no correlation between VEGF-C and VEGF-D.③The expression of VEGF-C, VEGF-D and VEGFR-3 in colorectal cancers was not correlated with age,gender,site and dimension of lesion,types of gross and histological,degree of differentiation and liver and pulmonary metastasis,but correlated significantly with Dukes' stage(P=0.0234,P=0.0003,P=0.0429)and lymph node me tastasis(P=0.0059,P＜0.01,P=0.0068).The increased death rate(P=0.0374,P=0.0127) and poor survival(P＜0.01,P＜0.01)were observed in the colorectal cancer patients with positive ex- pression of VEGF-C and VEGFR-3 when comparing with the patients of the negative expressions,but the expression of VEGF-D in colorectal cancers was not correlated with prognosis of the patients.Con- clusions Colorectal cancer cells may secrete lymphangiogenetic growth factors VEGF-C,VEGF-D and their receptor VEGFR-3,which induce the growth of lymphatic vessel endothelium and lymphangiogene- sis by VEGF-C,VEGF-D/VEGFR-3 signaling pathway,further accelerate lymphatic metastasis of colo- rectal cancers.VEGF-C,VEGF-D and VEGFR-3 might be acted as molecular phenotypes of lym- phangiogenesis in coiorectal cancers and important markers for evaluating lymphatic metastasis and prog- nosis in patients with coloreetaI carcinoma.

Dipeptides ; administration & dosage ; therapeutic use ; End Stage Liver Disease ; drug therapy ; virology ; Female ; Hepatitis B virus ; Humans ; Male

Objective To study the characteristics of event-related potentials P300 in patients with anxiety disorder(AD). Methods P300 tests were carried out in 30 patients with AD and 30 healthy adult controls. ResultsPatients with AD had significantly delayed P3 latency ([326?16] ms vs [339?19]ms, P