Cancer of unknown primary site in the mandibular region: A case report.

The diagnosis and treatment of cancer of unknown primary site (CUP) present with difficulties and produce a poor prognosis. The current study presents the case of a patient with CUP in the mandibular region was treated with docetaxel and lobaplatin chemotherapy, and vascular embolization of the tumor. The tumor size was markedly reduced and the patient's quality of life improved following radiotherapy. The present case report is accompanied by a discussion of the literature to contextualize the treatment regimen for patients with CUP. These findings will support current treatment practices, inform oncologists and benefit patients with cancer.

Tetracysteine as a reporter for gene therapy / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To study the feasibility of using tetracysteine (TC) reporter in gene therapy.</p><p><b>METHODS</b>Effects of TC reporter and conventional reporter genes encoding green fluorescence protein (GFP) and luciferase (Luc) on expression and function of the therapeutic gene MGMT(P140K) were compared. Cytotoxicity and drug resistance were studied by Western blot. TC reporter used in therapy was analyzed by flow cytometry (FCM).</p><p><b>RESULTS</b>The TC reporter had no toxicity to cells and neither affected the expression or activity of therapeutic gene as compared to GFP and Luc. TC could be used in blood sample detection.</p><p><b>CONCLUSION</b>TC is a new kind of reporter gene for lentiviral vector in future gene therapy.</p>

Improving baculovirus transduction of mammalian cells by spinoculation / 生物工程学报

Recently many reports have described that recombinant baculovirus could serve as a new gene transfer vehicle for mammalian cells with many unique advantages. In this study, the constructed recombinant baculovirus BacV-CMV-EGFPA containing the enhanced green fluorescent protein (eGFP) gene driven by CMV promoter was used to explore the feasibility of improving the efficiencies of transduction experiment in CV-1 cells by centrifugal method. Refer to the centrifugal transduction protocol of recombinant lentivirus, CV-1 cells were incubated with the culture supematant of Sf-21 cells infected by BacV-CMV-ECFPA (moi = 30) and then centrifuged at 600g for 1 h at RT, reporter gene transfer and expression efficiencies were analyzed by flow cytometry (FCM) 48h post transduction. Results showed that centrifugal method can achieve higher gene delivery and expression efficiencies than transduction by simple virus-cell mixing for 4h at 27 t with least impairment to cell viability. The centrifugal transduction protocol was further optimized by testing different centrifugal times, post-centrifugation incubation times and surrounding solutions. We found that centrifugation at 600g for 1 h at RT is sufficient to achieve the highest transduction efficiencies in target cells and PBS is more suitable than other surrounding solutions. Compared with previous protocol in which tranduction occurs for 4 - 8h at 27 degrees C, centrifugal method developed in this study could achieve more higher transduction efficiencies in more shorter time. Nine different mammalian cell lines (CV-1, 293FT, HepG2, 293T, CHO, C127, MT4, H9, Molt-4) were used to investigate the feasibility of delivering exogenous genes into different mammalian cells with the BacV-CMV-EGFPA supernatant (moi = 30) at 600g for 1h in PBS surrounding solution at RT. Results showed that most mammalian cell lines used in this study could be effectively transduced with recombinant baculoviruses by centrifugal method, and more higher and satisfactory transduction efficiencies could be achieved in primate adherent culture cells than in suspended culture cells. These results show that the baculovirus centrifugal transduction protocol have notable advantages: more rapid, efficient and nontoxic, and could be easily used in daily common experiments.

[The first confirmed human case of avian influenza A (H5N1) in mainland, China].

OBJECTIVE: To ascertain the causation of a family cluster involving two undefined pneumonia cases, a 12-year-old girl and her brother, reported October, 2005 in Xiangtan county, Hunan province. METHODS: Information on epidemiology and clinical manifestation of the cases was collected from interviewing the keyman and referring to related medical records. The environment exposure of the cases to their households and the timeline of the illness were reproduced, using this information. Medical check-up was undergone among the close contacts of the cases and on sick/dead poultry. Throat swab of the cases were collected and tested by both RT-PCR and real-time PCR to detect viral nucleic acids of A/H5N1, and were then inoculated into special pathogen free (SPF) embryonated hens' eggs. Serum of the cases including acute and convalescent phases were also collected and tested by microneutralization and haemagglutination-inhibition (HI) assays to detect H5-specific antibodies. RESULTS: Both the girl and her brother developed fever 2 and 4 days after sudden deaths of chickens being raised in the same house. Both of them had developed pneumonia and the girl died from acute respiratory distress syndrome (ARDS) complicated with multi-organ failure. The boy survived and subsequently discharged from hospital. An eighth-day serum from the girl tested H5 antibody negative, while 4-fold and greater increased in antibody titers were detected in serum from the boy using microneutralization and HI assays in sequential acute and convalescent sera. Of 192 cases, only one doctor who cared for the girl during hospitalization had upper respiratory symptoms but tested negative for H5N1 by microneutralization assay. CONCLUSION: The boy was the first confirmed human case of avian influenza A (H5N1) in the mainland of China and his sister was diagnosed clinically. The most probable explanation of these two cases was that the transmission of H5N1 virus from infected poultry within the same household environment. No evidence of human-to-human transmission was noted in the family cluster.

[Laboratory diagnoses of the first confirmed human case of avian influenza A (H5N1) in the mainland of China].

BACKGROUND: To determine the etiologic agent of an atypical pneumonia human case admitted to Xiangtan City hospital, Hunan Province in Oct. 2005. METHODS: The patient's respiratory tract samples and serum were collected. Throat swabs were tested by microneutralization and hemagglutination-inhibition assays. RESULTS: The results of nucleic acid detection of all respiratory samples were negative and virus isolation was also negative. The H5-specific antibodies of convalescence showed a 4-fold greater rise than acute phase. CONCLUSION: The atypical pneumonias case was confirmed as the first human case of avian influenza A (H5N1) infection in the mainland of China.

Hydrophobicity of reactive site loop of SCCA1 affects its binding to HBV / 生物工程学报

Squamous cell carcinoma antigen 1 (SCCA1), a member of the ovalbumin family of serine protease inhibitors, includes several variants. It was reported that expression of two SCCA1 (BP and AJ515706) in cells results in increased binding of HBV to these cells by the interaction of the expressed BP and AJ515706 with HBV pre-S1 domain. In this study, a SCCA1 (A1) was isolated from HepG2, but it appears to lack this ability. A possible role of two mutants, A1-BP and BP-A1, constructed by interchanging the carboxyl terminal of A1 and BP, was investigated. Cells expressing A1-BP rather than BP-A1 showed an increased virus binding capacity. Comparison of A1 sequence with the sequence of BP indicated the presence of only three amino acid changes in the carboxyl terminal, two of them in the reactive site loop (RSL) of SCCA1. Primary structure analysis revealed that the hydrophobicity of BP and AJ515706 in this domain is higher than that of A1. Changing the aa349 of A1 from low hydrophobic glutamic acid to high hydrophobic valine enhanced HBV binding. In contrast, changing the aa349 of BP from valine to glutamic acid reduced HBV binding. Our finding suggests that the hydrophobicity of RSL of SCCA1 may play an important role in HBV binding to cells.

[A study on early detection for seven infectious diseases].

OBJECTIVE: To provide methods and alert thresholds which are scientific, sensitive, specific and practical for Early Warning System in Public Health Surveillance. METHODS: Alert data was based on historical infectious diseases reports. Control chart was used to detect outbreaks or epidemics. An epidemic was defined by consulting Specialists. After calculating sensitivity, specificity, positive predictive value and describing receiver-operating characteristic curve (ROC), the optimal model and thresholds were chosen. RESULTS: At 80 percentile, the sensitivities and the specificities of epidemic haemorragia fever, hepatitis A, dysentery, epidemic cerebrospinal meningitis and malaria were over 90%, and there was a high efficacy of early warning. At 90 percentile, the sensitivities and the specificities of tuberculosis and measles were over 85%, and there was a high efficacy of early warning also. CONCLUSION: Control chart based on five years was chose as a essential method in early warning system. The alert threshold for epidemic haemorragia fever, hepatitis A, dysentery, epidemic cerebrospinal meningitis and malaria was 80 percentile. The alert threshold for tuberculosis and measles was 90 percentile.

Mammalian gene-transfer and expression efficiencies of baculovirus bacV-CMV-EGFPA / 生物工程学报

It has been reported that baculoviruses could serve as a new gene-transfer vehicle for mammalian cells. We have previously constructed recombinant baculovirus BacV-CMV-EGFPA and have proven that mammalian cells could be effectively infected by the recombinant baculovirus. In this report, we studied the efficiency of baculovirus to deliver exogenous gene into twenty mammalian cells, including twelve human cell lines (WI-38, Hela, HepG2, 293, PLC/PRF/5, 143B, MCF-7, BGC-223, DMS 114, CNE, Raji, LCL-cm), seven murine cell lines (BNL 1ME A.7R.1, CHO-K1, L-929, JC, PT67, NIH3T3, P815) and one monkey cell line (CV1). Results showed that most mammalian cell lines could be transduced by the recombinant baculovirus, the transduction efficiencies of the human and monkey cell lines were markedly higher than that of murine cell lines, and the transduction efficiencies in adherent culture cell lines higher than that of suspend culture cell lines, implying that the infection efficiency of the baculovirus may be correlative with the organism used and the growth properties of the cell lines. The plasmid pcDNA3. 1-EGFP, which contains the CMV promoter and EGFP reporter gene, was next transfected by LipofectAMINE into a number of mammalian cells, especially those cells that were low in the baculovirus transfection. Results showed that the CMV promoter could effectively direct the expression of the reporter gene in these mammalian cells. Therefore the gene-expression efficiencies in different mammalian cell lines by the recombinant baculovirus which contains the same CMV promoter were dictated by the ability of the baculovirus to enter the cell lines. This study suggested that the recombinant baculovirus vector is more suitable for gene expression in primate adherent culture cells than in murine cells and suspend culture cells.

Rapid and efficient expression of foreign genes in mammalian cells by baculovirus vectors / 生物工程学报

The baculovirus insect cell expression system has been used extensively for the expression of recombinant proteins in insect cells. Recently, reports have described that recombinant baculoviruses can transduce a broad spectrum of primary and established mammalian cells, which shows the baculoviruses could serve as a new gene-transfer vehicle for mammalian cells. In this report, we further research the modification of baculovirus vector and the way to deliver exogenous gene into mammalian cells. On the base of Bac-to-Bac baculovirus insect cell expression system, two recombinant baculoviruses (BacV-CMV-EGFPA, BacV-CMV-EGFPB) were constructed containing different direction of CMV promoters which controll the expression of a reporter gene (EGFP). We found that CMV promoter could direct expression of reporter gene in Sf9 cells with relatively low efficiency. The culture supernatant of Sf9 cells which have been infected by the recombinant baculoviruses for four days were collected and the titers of the viruses in culture supernatant were determined by plaque assay on Sf9 cells. The HepG2 cells, an human hepatocellular carcinoma cell line, were directly incubated with the collected culture supernatant which contains the recombinant baculoviruses for 8 hours in 37 degrees C CO2 incubator (moi = 100). Twenty-four hours post transduction the efficiencies of gene-transfer and expression were analyzed by flow cytometry (FCM) which detect the green fluorescence of individual cells. Results show that these two recombinant baculoviruses have similar gene-transfer and expression efficiency in HepG2 cells, which means the direction of CMV promoters has no effects on reporter gene expression. The optimal transduction conditions of incubating the mammalian cells with the culture supernatant of Sf9 cells infected by recombinant baculoviruses for four days were determined by FCM assay in HepG2 cells. The HepG2 cells inoculated in 24-well plate (5 x 10(4)/well) were incubated with the culture supernatant (BacV-CMV-EGFPA, 1.2 x 10(7) pfu/mL) serially diluted by DMEM culture medium containing 10% FBS and the transduction times ranged from 1 to 24 hours. Twenty-four hours post transduction the efficiencies of gene-transfer and expression were analyzed by FCM. Results show that incubating the target cells with the 1:1 diluted culture supernatant (moi = 50) for 12 hours in 37 degrees C CO2 incubator would achieve the highest infection and expression efficiency with the least impairment on cell viability. We compared the gene-transfer and expression efficiency of recombinant baculovirus in HepG2 and CV1 cells with lipofectAMINE and recombinant retrovirus system, results show that under the similar conditions the recombinant baculovirus could achieve the highest gene-transfer and expression efficiency than the other two systems. So we can draw a conclusion that directly incubating the mammalian cells with the culture supernantant of the infected Sf9 cells could serve as a very convenient way for rapid and efficient expression of foreign gene in mammalian cells.