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Noroviruses are the leading cause of acute gastroenteritis and food-borne diseases worldwide. Thus, a rapid, accurate, and easy-to-implement detection method for controlling infection and monitoring progression is urgently needed. In this study, we constructed a novel sandwich-type electrochemical biosensor integrated with two specific recognition elements (aptamer and peptide) for human norovirus (HuNoV). The electrochemical biosensor was fabricated using magnetic covalent organic framework/pillararene heterosupramolecular nanocomposites (MB@Apt@WP5A@Au@COF@Fe3O4) as the signal probes. The sensor showed high accuracy and selectivity. The detection method does not need the extraction and amplification of virus nucleic acid and has a short turn-around time. Intriguingly, the proposed biosensor had a limit of detection of 0.84 copy mL-1 for HuNoV, which was the highest sensitivity among published assays. The proposed biosensor showed higher sensitivity and accuracy compared with immunochromatographic assay in the detection of 98 clinical specimens. The biosensor was capable of determining the predominant infection strain of GII.4 and also GII.3 and achieved 74% selectivity for HuNoV GII group. This study provides a potential method for point-of-care testing and highlights the integrated utilization of Apt and peptide in sensor construction.

The HLA-I antigen processing machinery (APM) plays a crucial role in the anticancer immune response. The loss of surface expression of HLA-I molecules is particularly important as this enables tumor cells to evade recognition and lysis by cytotoxic T-lymphocytes. Transcriptional control of the APM genes is regulated by the nuclear factor kappa B (NF-κB). BCRFl is an Epstein-Barr virus homologue of human IL-10 (hIL-10) and is known as viral IL-10 (vIL-10). vIL-10 shares many immunosuppressive effects with hIL-10 but lacks the immunostimulatory effect of hIL-10. The aim of this study was to assess whether vIL-10 inhibits APM components (TAP-1, TAP-2, LMP-2, LMP-7 and HLA-I) through the NF-κB signaling pathway in nasopharyngeal carcinoma. This work demonstrated that vIL-10 inhibited NF-κB activation by blocking IKK phosphorylation and promoting the expression of IKB. TNF-α treatment led to a strong translocation of NF-κB p65, whereas pretreatment with vIL-10 before TNF-α treatment blocked NF-κB p65 translocation. vIL-10 also inhibited TNF-α-induced DNA-binding of NF-κB p65 in the nucleus. Furthermore, chromatin immunoprecipitation analysis demonstrated that NF-κB p65 could bind to the TAP-1, TAP-2, LMP-2, LMP-7 and HLA-I gene promoters, and after TNF-α stimulation, the down-regulation of TAP-1, TAP-2, LMP-2, LMP-7 and HLA-I transcription by vIL-10 correlated with the suppression of NF-κB in CNE-2 cells. Surprisingly, vIL-10 inhibits only TAP-1 and LMP-7 transcription in CNE-1 cells. Taken together, these results suggest that the inhibition of NF-κB activity may be an important mechanism for vIL-10 suppression of APM (TAP-1, TAP-2, LMP-2, LMP-7 and HLA-I) gene transcription in CNE-2 cells.

Laggera pterodonta is commonly used for treating influenza in Southwest China, especially in Yunnnan province. The main clinical effects of L. pterodonta include anti-influenza, anti-microbial, anti-inflammatory. To investigate the anti-influenza A (H1N1) virus effect of L. pterodonta, neutralization inhibition and proliferation inhibition tests were performed. MDCK culture method was used to observe the cytopathic effect (CPE) of extracts from L. pterodonta in inhibiting influenza A (H1N1) virus and haemagglutination titre of H1N1 virus in vitro. The culture medium were collected at 24 h, 48 h, 72 h, 96 h, and detected by Real time RT-PCR, in order to compare the effect of different extracts from L. pterodonta on in vitro proliferation of H1N1, virus. The result of neutralization inhibition test showed that hemagglutination titer of ethyl acetate extract were 8 times lower at 72 h; in proliferation inhibition test, hemagglutination titer of ethyl acetate extracts reduced by 2 and 4 times. According to the results of Real time RT-PCR test, the H1N1 inhibition ratio of ethyl acetate extract was 72.5%, while the proliferation inhibition ratio of ethyl acetate extract was 25.3%; as for petroleum ether extracts, the H1N1 inhibition ratio was 60.2%, while the proliferation inhibition ratio was 81.4%. In conclusion, both ethyl acetate extract and petroleum ether extract of L. pterodonta have significant neutralization and direct proliferation inhibition effects on influenza A virus.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in a variety of malignant cells, but not in normal cells. This preferential toxicity to the abnormal cells renders TRAIL potentially a very powerful therapeutic weapon against cancer. However, a requirement for large quantities of TRAIL to suppress tumor growth in vivo is one of the major factors that has hindered it from being widely applied clinically. To overcome this, we constructed a replication-deficient adenovirus that carries a human full-length TRAIL gene (Ad-TRAIL) and tested its efficacy against a lung cancer model system in comparison to that of the recombinant soluble TRAIL protein.To investigate the antitumor activity and therapeutic value of the Ad-TRAIL on the non-small cell lung cancer (NSCLC), four NSCLC cell lines, namely, YTMLC, GLC, A549, and H460 cells, were used. TRAIL protein expression was determined by Western blotting and flow cytometry. Cell viability was analyzed by proliferation assay, and DNA ladder and cell-cycle analysis were used to identify apoptosis. To further evaluate the effect of Ad-TRAIL in vivo, YTMLC cells were inoculated to the subcutis of nude mice. The Ad-TRAIL was subsequently administered into the established tumors. Tumor growth and the TRAIL toxicity were evaluated after treatment.YTMLC cells infected with Ad-TRAIL showed decreased cell viability and a higher percentage of apoptosis. Similar, Ad-TRAIL treatment also significantly suppressed tumor growth in vivo.TRAIL gene therapy provides a promising therapy for the treatment of NSCLC.

To select the adaptive strain of Dengue-III virus D9964 strain (China strain) in KMB17 cells, elucidate the biological characteristics and proliferation kinetics of adapted strain,and to lay the foundation for the development dengue inactivated vaccine and attenuated live vaccine. Dengue-III virus D9964 strain was firstly identified by amplification of the type-specific gene segment of dengue virus by RT-PCR, and the titer was determined. The virus was then subcultured in KMB17 cells with 4.0 MOI till completely adaptive to multiply in cell S. After subculturing in KMB17 cells for 10 consecutive passages, the adapted strain was screened, and purified through plaque. Virus titer of each passage was measured by microtitrimetry, and the antigenicity was detected by IFA. The purified virus RNA extraction of 3-8 day cultured from KMB17 cells, was performed to detect the proliferation kinetics of adapted strain. The results showed that after continuous subculture, dengue-III virus D9964 (China) strain could stably proliferate in KMB17 cells, a highly puried virus adapted strain was obtained through plaque purification. Purified strain maintained the good antigenicity with a highest replicating activity during the 5th-6th day.

To analyze the genomic sequence characteristics of a human Echovirus 9(ECHO-9) strain isolated from a child with Hand-foot-mouth disease (HFMD) in Kunming, Yunnan Province, in 2010. The complete genome sequence of a human echovirus 9 strain, MSH-KM812-2010 was determined. As other human enterovirus, its genome was 7,424 nucleotides (nts) in length and encoded for 2,203 amino acids (aas). In comparison to other human enteroviruses, MSH-KM812-2010 strain had the highest homology with other strains of human echovirus 9 in structural genomic regions and more homologous to other serotypes of B specie than to human echovirus 9 in non-structural genomic regions. Phylogenetic analysis based on complete VP1 gene revealed that the sequences of human echovirus 9 segregated into three distinct clades A, B and C with more than 15. 0% diversity between clades. All Chinese isolates belonged to the same clade. RDP3 and Blast revealed evident recombination in non-structural genomic regions. This report is the first to, describe the complete genome of the human echovirus 9 in China and provide an overview of the diversity of genetic characteristics of a circulating human echovirus 9.

The human leukocyte antigen (HLA)-I and antigen-processing machinery (APM) are crucial in the anti-cancer immune response. The aim of this study was to assess the clinical significance of the APM components [transporters associated with antigen processing (TAP)-1 and -2 and HLA-I] in nasopharyngeal carcinoma (NPC). A total of 58 NPC specimens and 20 healthy specimens used as control were evaluated by semiquantitative immunohistochemistry for three APM components (TAP-1, TAP-2 and HLA-I). The expression of the APM components in NPC was downregulated. CD4+ and CD8+ T cells were measured by flow cytometry and IL-10 was measured by ELISA. The number of CD8+ T cells and the expression of IL-10 were higher and the number of CD4+ T cells was lower in NPC, compared to the controls. The number of CD8+ T cells and the expression of IL-10 were negatively correlated with TAP-1, TAP-2 and HLA-I expression. The clinical phase, lymph node metastasis, distant metastasis, pathological type, TAP-1 expression, TAP-2 expression and HLA-I expression were identified as prognostic factors by the Kaplan-Meier analysis. A multivariate analysis using a Cox regression model indicated that distant metastasis and the downregulation of HLA-I expression were independent unfavorable prognostic factors. In conclusion, the lower expression of HLA-I induced immunosuppression in NPC patients and was associated with a poor prognosis.

To investigate E6 and E7 gene variations of human papillomavirus type 16 in Yunnan Province, DNA was extracted from 2000 gynecological outpatient samples. For Human papillomavirus (HPV) genotyping, the genomic DNA was first amplified by the consensus MY09/MY11 primer pair followed by nested PCR with GP5+/GP6+ primers, then the PCR products were subjected to direct DNA sequencing. A total of 20 HPV-16 viral DNAs were identified. E6 and E7 genes of HPV-16 viral DNA were then amplified using E6 and E7 specific primers, the PCR products were purified and sequenced. The results showed that mutations were found at nucleotide position 178 of HPV-16 E6 gene in 10 cases,the mutation rate was 50%; For HPV-16 E7 gene, the mutations were found at nucleotide position 647 in 10 cases; the mutation rate was 50%. Phylogenetic analysis showed that Asian (As) variants of HPV-16 were predominated in Yunnan, China. None of African-1, African-2 variants of HPV-16 was found in this region.

To describe the genetic characterization of complete genome from a human coxsackievirus A16 (CA16) strain KMM08, isolated in Yunnan, China, in 2008.By using RT-PCR, the seven fragments contained about 1000 nucleotides in the complete genome were sequenced. The sequences were aligned with other enterovirus sequences downloaded from GenBank using Mega 4.1, RDP3 and SimPlot 3.5.1 software.As in other human enterovirus, its genome was 7409 nucleotides in length, encoding for 2193 amino acids. KMM08 strain was closely related to other reference strains of B genotype. In the complete genome, the homology of nucleotide and amino acid among the eleven CA16 isolated strains were 79.0% - 98.2% and 94.5% - 99.3%, respectively. The rates of homology were 79.1% and 94.8% when comparing with that of G10 strains and 78.7% and 89.0% comparing with that of BrCr strains, respectively. SZ-HK08-3 strain had high homology when compared to other strains. In different segment of genome, the rates of homology were 97.0% - 99.0% and 98.0% - 100.0% when compared with that of SZ-HK08-3 strains, respectively. The rates of homology were 74.2% - 86.9% and 90.9% - 97.0% when compared with that of G10 strains, respectively and were 65.0% - 84.9% and 71.0% - 95.2% when compared with that of BrCr strains. Data from Phylogenetic analysis showed that KMM08 belong to genotype B. The putative recombinant Tainan-5079-98 was detected positive with RDP3 and SimPlot 3.5.1.KMM08 strains isolated in Yunnan in 2008 belonged to B genotype of coxsackievirus A16. The possible occurrence of inter-typic recombination would involve EV71 and CA16.

Objective. To establish a standardized animal model for liver fibrosis with the same assessment criteria for liver fibrosis studies that have been established on a unified platform.Methods. The standardized liver fibrosis model was established using Sprague-Dawley (SD) rats that either received an intraperitoneal injection of carbon tetrachloride (CCl4) in small dosages or ingested an ethanol solution.Results. The definite corresponding rules among modeling of different weeks and corresponding serology indices as well as different pathological staging can be observed by modeling with small dosages and slow, individualized, and combined administrations.Conclusion. This method can be used for the standardized establishment of a liver fibrosis model in rats across 5 pathological stages, ranging from S0 to S4, with a high success rate (89.33%) and low death rate (17.3%) because of the application of multiple hypotoxic chemicals for modeling. We refer to the criteria of Histological Grading and Staging of Chronic Hepatitis for Fibrosis established by the 10th World Digestive Disease Academic Conference in Los Angeles in September 1994 (revised in November 2000).

To prepare small interfering RNA (siRNA) targeting survivin for inhibition of endogenous survivin gene expression in Hela cell line and evaluate its effect on promoting Hela cell apoptosis.The recombinant plasmid pshRNA-survivin-1 and pshRNA-survivin-2 were constructed and transfected into Hela cells, in which the expression level of survivin was determined by immunofluorescence staining and survivin gene transcription detected by semi-quantitative RT-PCR.Introduction of the plasmids pshRNA-survivin-1 and pshRNA-survivin-2 into Hela cells resulted in efficient and specific inhibition of survivin expression as demonstrated by immunofluorescence staining. Semi-quantitative RT-PCR showed that mRNA transcription of survivin gene was reduced. In contrast, the control plasmid did not exhibit any inhibitory effect on the protein expression and mRNA transcription of survivin gene. PI-Annexin V staining indicated an apoptosis rate of the transfected Hela cells of (36.02-/+2.12)% (P0.01) and (35.29-/+2.02)% (P0.01), respectively.The prepared siRNA targeting survivin gene is capable of inducing marked inhibitions of survivin protein expression and RNA transcription and significant enhancement of apoptosis in Hela cells, which shed light on a new strategy in gene silence therapy targeting survivin.

To efficiently express and identify recombinant human survivin in E. coli.Survivin cDNA was amplified by reverse transcriptional (RT)-PCR and cloned into the prokaryotic expression vector pBV220, followed by expression of the recombinant plasmid in E.coli strain BL21 (Gold). To obtain survivin protein, DEAE-Sepharose Fast-Flow ion exchange chromatography and Sephacryl S-200 gel filtration were performed. Western blot analysis was used for detecting the expressed product.Survivin protein was expressed in E.coli in the form of inclusion body at the expression level over 30% of the total cell protein. After ion exchange chromatography and gel filtration, the recombinant protein reached a purity over 95% and exhibited specific reaction with mouse anti-human antibody.Survivin protein with high purity can be obtained by the method described above to facilitate further study of the anti-apoptosis function of survivin.

To investigate the presentation of a neutralization epitope-containing peptide antigen of hepatitis E virus (HEV) on chimeric virus-like particles (VLPs) of hepatitis B surface antigen (HBsAg).The gene fragment corresponding to amino acids (aa) 551-607 (HEnAg) of HEV capsid protein, which contains the only neutralization epitope identified to date, was fused via a synthetic glycine linker in frame with the gene of HBsAg. The resulted fusion gene was then integrated through transformation into the genome of Pichia pastoris under the control of a methanol-induced alcohol oxidase 1 (AOX1) promoter and expressed intracellularly. The expression products in the soluble cell extracts were characterized by Western blot, ELISA, CsCl density gradient analysis, and electron microscopic visualization.The novel fusion protein incorporating HBsAg and the neutralization epitope-containing HEnAg was expressed successfully in Pichia pastoris with an expected molecular weight of approximately 32 kD. It was found to possess the ability to assemble into chimeric HBV/HEV VLPs with immunological physical and morphological characteristics akin to HBsAg particles. Not only did the chimeric VLPs show high activity levels in a HBsAg particle-specific ELISA but they were also strongly immunoreactive with hepatitis E (HE) positive human serum in a HEV specific ELISA, indicating that HEnAg peptide fragments were exposed on VLP surfaces and would be expected to be readily accessible by cells and molecules of the immune system. Similarity between chimeric VLPs to highly immunogenic HBsAg particles may confer good immunogenicity on surface-displayed HEnAg.The chimeric HBV/HEV VLPs produced in this study may have potential to be a recombinant HBV/HEV bivalent vaccine candidate.

To construct and express the gene encoding hIL-6/GM-CSF fusion protein.The genes encoding the two hIL-6/GM-CSF fusion proteins were constructed in pBV220 expression vector. Fusion proteins were expressed in E.coli BL-21 and purified through Q Sepharose HP ion exchange chromatography and Sephacryl S-200 gel filtration columns. The biologic activities of the fusion proteins were detected by proliferation of hIL-6 dependent cell line B9 and hGM-CSF dependent cell line TF1 with MTT assay.Both fusion proteins were expressed in E.coli BL-21 in the form of inclusion body. The expression levels were more than 25% of the total cell lysates. Both fusion proteins were obtained with high purity which had both hIL-6 and hGM-CSF biologic activities.Two hIL-6/GM-CSF fusion proteins with high purity and bilolgic activities have been acquired successfully.

The huGM-CSF(9-127)-IL-6(29-184) fusion protein was precipitated on column when being purified by Q Sepharose H.P. ion exchange chromatography after renaturation by dilution. To solve this problem, a novel purification and refolding strategy was adopted. Inclusion bodies was first purified by Q Sepharose H.P. ion exchange in 8 mol/L urea, followed by in situ refolding on column by Sephacryl S-200. Renatured fusion protein was obtained in a purity of more than 95%. It was showed that the method of refolding on gel filtration column is efficient, with relative refolding rate at 80%. By the whole procedure, refolding and purification of recombinant protein can be performed within one day. This strategy is also promising to be applied in large scale purification and refolding of recombinant protein from inclusion bodies in E. coli.

Littoral cell angioma (LCA) is a rare splenic vascular neoplasm that arises from the cells lining the red pulp sinuses. It is deemed to be a benign and incidental lesion. The earliest literature report of littoral cell angioma has been described by Falk. The examination of samples after splenectomy reveals similar pathological change and its change rule is summarized. However, many recent reports have described it to be a malignant tumor with congenital and immunological associations. Generally speaking, the definitive diagnosis can only be made after histological and immunohistochemical profiles. In this case report, we presented the case of a 48-year-old woman with multiple splenic LCAs. Initially, the patient was characteristics of abdominal distension, weakness and fatigue. Multiple hemangiomas were observed in the spleen through abdominal ultrasonic diagnosis. Computed tomography (CT) scans revealed the splenomegaly with multiple round and hyperdense lesions. The patient subsequently underwent splenectomy. Postoperative histological and immunohistochemical studies confirmed the diagnosis of LCA. Based on the presentation of this case, clinical, radiographic and pathological results of LCA as well as recent advances in our understanding of this uncommon splenic lesion were reviewed. LCA is an uncommon splenic tumor diagnosed in patients with or without abdominal discomfort. Only a few case reports regarding this kind of tumor have been published as inconsistent results. In the present paper, we have reported a case of LCA and reviewed the literature.