In Vitro and In Vivo Antibacterial Activity of Patchouli Alcohol from Pogostemon cablin / 中国结合医学杂志

OBJECTIVE@#To investigate the antibacterial activity of patchouli alcohol (PA) against 127 bacteria strains, including the common bacteria and drug-resistant bacteria strains both in the in vitro and in vivo tests.@*METHODS@#For the in vitro trial, the antibacterial property of PA against 107 Gram-positive and 20 Gram-negative bacteria strains was screened by agar double dilution method. For the in vivo trial, specific pathogen free Kunming strain of both male and female white mice, were used to test the protective ability of PA after being injected with the median lethal dose of the tested strains.@*RESULTS@#PA possessed antibacterial activity against all the tested 127 strains. In the in vitro test, PA could inhibit both Gram-negative bacteria (25-768μg/mL) and Gram-positive bacteria (1.5-200μg/mL). Particularly, PA was active against some drug-resistant bacteria like methicillin-resistant Staphylococcus aureus (MRSA). PA also exhibited in vivo anti-MRSA activity in mice via intraperitoneal injection. PA could protect mice entirely infected with MRSA at 100 and 200 mg/kg, while 80% mice injected with MRSA could be protected at a low dose of 50μg/mL.@*CONCLUSION@#PA might be a potential antibacterial drug from natural sources and might be worthy to explore its mechanism and application in further study.

An Investigation on the Molecular Characteristics and Intracellular Growth Ability among Environmental and Clinical Isolates of Legionella pneumophila in Sichuan Province, China / 生物医学与环境科学（英文）

OBJECTIVE@#To investigate the molecular characteristics and intracellular growth ability of Legionella pneumophila (L. pneumophila) strains from 1989 to 2016 in Sichuan Province, China.@*METHODS@#Seventy-nine isolates of L. pneumophila were collected from environmental and clinical sources, including cooling towers, hot springs, bath water, fountains, and patients, and identified with 16S rRNA gene analysis and serum agglutination assay. The isolates were then typed by Sequence-Based Typing (SBT), and Genotyping of forty-two LP1 strains were analyzed by means of multiple-locus VNTR analysis with 8 loci (MLVA-8). All strains were further analyzed for two virulence genes: Legionella vir homologue (lvh) and repeats in structural toxin (rtxA). The intracellular growth ability of 33 selected isolates was determined by examining their interaction with J774 cells.@*RESULTS@#All isolates were identified to L. pneumophila including 11 serogroups, among which the main serogroup were LP1, accounting for 54.43%. Thirty-three different sequence types (STs) from five main clonal groups and five singletons were identified, along with 8 different MLVA patterns. Both the lvh and rtxA loci were found in all 79 strains. Thirty isolates showed high intracellular growth ability in J774 cells.@*CONCLUSION@#L. pneumophila is a potential threat to public health, and effective control and prevention strategies are urgently needed.

Potential Clinical Risk of Inflammation and Toxicity from Rare-Earth Nanoparticles in Mice / 中华医学杂志(英文版)

<p><b>Background</b>Nanotechnology is emerging as a promising tool to perform noninvasive therapy and optical imaging. However, nanomedicine may pose a potential risk of toxicity during in vivo applications. In this study, we aimed to investigate the potential toxicity of rare-earth nanoparticles (RENPs) using mice as models.</p><p><b>Methods</b>We synthesized RENPs through a typical co-precipitation method. Institute of Cancer Research (ICR) mice were randomly divided into seven groups including a control group and six experimental groups (10 mice per group). ICR mice were intravenously injected with bare RENPs at a daily dose of 0, 0.5, 1.0, and 1.5 mg/kg for 7 days. To evaluate the toxicity of these nanoparticles in mice, magnetic resonance imaging (MRI) was performed to assess their uptake in mice. In addition, hematological and biochemical analyses were conducted to evaluate any impairment in the organ functions of ICR mice. The analysis of variance (ANOVA) followed by a one-way ANOVA test was used in this study. A repeated measures' analysis was used to determine any significant differences in white blood cell (WBC), alanine aminotransferase (ALT), and creatinine (CREA) levels at different evaluation times in each group.</p><p><b>Results</b>We demonstrated the successful synthesis of two different sizes (10 nm and 100 nm) of RENPs. Their physical properties were characterized by transmission electron microscopy and a 980 nm laser diode. Results of MRI study revealed the distribution and circulation of the RENPs in the liver. In addition, the hematological analysis found an increase of WBCs to (8.69 ± 0.85) × 10/L at the 28 day, which is indicative of inflammation in the mouse treated with 1.5 mg/kg NaYbF:Er nanoparticles. Furthermore, the biochemical analysis indicated increased levels of ALT ([64.20 ± 15.50] U/L) and CREA ([27.80 ± 3.56] μmol/L) at the 28 day, particularly those injected with 1.5 mg/kg NaYbF:Er nanoparticles. These results suggested the physiological and pathological damage caused by these nanoparticles to the organs and tissues of mice, especially to liver and kidney.</p><p><b>Conclusion</b>The use of bare RENPs may cause possible hepatotoxicity and nephritictoxicity in mice.</p>

Optimization of preparation process of Jianpi Yishen Pill based on pharmacodynamic screening and orthogonal test / 中草药

Objective To screen the preparation technology of Jianpi Yishen Pill (JYP) by pharmacodynamics screening, and optimize it by orthogonal test to determine the best extraction technology. Methods The chronic renal failure model in rats was established by 5/6 nephrectomy. Three technological routes of JYP were selected, including A (powder of medicinal materials and decocting with water), B (powder of medicinal materials, extraction of volatile oil, and decocting with water), and C (extraction of volatile oil and decocting with water), with the content of Cr and BUN in rats as index. The orthogonal test was optimized by using the content of astragaloside and the quality of solid as indexes, with water volum, decoction time, decoction freguency as factors. Results The pharmacological efficacy test showed that technology A could obviously improve the rat model of chronic renal failure, and it could be used as the molding technology of this prescription pill. In this technology, five herbs such as Atractylodis Macrocephalae Rhizoma were crushed into fine powder alone, and the optimal extraction condition of other medical materials such as Astragalus Radix was as follows: 8-fold water per time, decocting 1 h, for two times. Conclusion JYP can obviously improve the content of Cr and BUN in rats model of 5/6 nephrectomy. The optimized preparation technology is stable and feasible, which can provide the basis for the follow-up development of JYP.

Rare-earth Nanoparticle-induced Cytotoxicity on Spatial Cognition Memory of Mouse Brain / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Luminescent rare-earth-based nanoparticles have been increasingly used in nanomedicine due to their excellent physicochemical properties, such as biomedical imaging agents, drug carriers, and biomarkers. However, biological safety of the rare-earth-based nanomedicine is of great significance for future development in practical applications. In particular, biological effects of rare-earth nanoparticles on human's central nervous system are still unclear. This study aimed to investigate the potential toxicity of rare-earth nanoparticles in nervous system function in the case of continuous exposure.</p><p><b>METHODS</b>Adult ICR mice were randomly divided into seven groups, including control group (receiving 0.9% normal saline) and six experimental groups (10 mice in each group). Luminescent rare-earth-based nanoparticles were synthesized by a reported co-precipitation method. Two different sizes of the nanoparticles were obtained, and then exposed to ICR mice through caudal vein injection at 0.5, 1.0, and 1.5 mg/kg body weight in each day for 7 days. Next, a Morris water maze test was employed to evaluate impaired behaviors of their spatial recognition memory. Finally, histopathological examination was implemented to study how the nanoparticles can affect the brain tissue of the ICR mice.</p><p><b>RESULTS</b>Two different sizes of rare-earth nanoparticles have been successfully obtained, and their physical properties including luminescence spectra and nanoparticle sizes have been characterized. In these experiments, the rare-earth nanoparticles were taken up in the mouse liver using the magnetic resonance imaging characterization. Most importantly, the experimental results of the Morris water maze tests and histopathological analysis clearly showed that rare-earth nanoparticles could induce toxicity on mouse brain and impair the behaviors of spatial recognition memory. Finally, the mechanism of adenosine triphosphate quenching by the rare-earth nanoparticles was provided to illustrate the toxicity on the mouse brain.</p><p><b>CONCLUSIONS</b>This study suggested that long-term exposure of high-dose bare rare-earth nanoparticles caused an obvious damage on the spatial recognition memory in the mice.</p>

A survey on the behavioral risk factors of chronic diseases among residents in Yongjia County / 预防医学

Objective To understand the health related behavior among residents in Yongjia County,and to provide the basis for developing disease control and health promotion strategies.Methods Using cluster random sampling,4 002 people over the age of 18 were selected for this study from Yongjia County.Questionnaire developed including smoking, drinking,diet,physical activities and so on;an interview was performed.Results Among the 4 002 participants,The overall smoking rate was 17.14%,while the smoking rate in male was 41.65%,higher than that of female 1.83% (P <0.01).Passive smoking rate was 52.92%,which was higher in male than that of female (P <0.01).The rate of smoking cessation was 13.82%.The rate of drinking was 19.94%,and the drinking rate in male was 40.29%,which was higher than that of female (P <0.01).Drinking cessation rate was 7.85% in women,and there was no significant difference between male and females (P >0.05).Vegetable oil was the major oil for cooking.Meat,aquatic products,eggs and soybean products were the major kinds of food.Active exercise rate was 37.78%,and qualified rate of daily walking was 35.66%.Conclusion There exist some kinds of unhealthy lifestyles and behavioral risk factors in Yongjia County,and appropriate intervention measures should be taken.

Antidiarrheal properties of different extracts of Chinese herbal medicine formula Bao-Xie-Ning / 中西医结合学报

<p><b>OBJECTIVE</b>Bao-Xie-Ning (BXN), a traditional Chinese herbal medicine (CHM) formula composed of Fructus Evodiae, Flos Caryophylli and Cortex Cinnamomi, and used for the treatment of infant diarrheal illness, was subject to systematic assessment for its putative multiple pharmacodynamic effects and pharmacological antidiarrheal mechanisms.</p><p><b>METHODS</b>High-performance liquid chromatography-diode array detector-electrospray ionization-mass spectrometric/mass spectrometry was developed and validated for identification and quantification of the main constituents in different extracts of BXN. Male Kunming mice weighing 20 to 25 g were used for detecting the antidiarrheal activity of the extracts. Ethanolic extract (EE), volatile oil extract (VOE), and aqueous extract (AE) of BXN were respectively subjected to pharmacodynamic and pharmacological comparison in assessing antidiarrheal effects with senna-induced diarrhea, castor oil-induced diarrhea, acetic acid-induced writhing assay, and isolated duodenum test.</p><p><b>RESULTS</b>The highest yields of three detected components of BXN, rutaecarpine, eugenol and cinnamaldehyde were observed in EE. EE showed the most remarkable antidiarrheal activity in dose-dependent and time-dependent manners in both senna- and castor oil-induced diarrhea models, and presented dose-dependent analgesic activity in acetic acid-induced algesthesia model. In addition, EE extract of BXN also exhibited strong antimobility action on the intestine and strongest depression on spontaneous contraction of isolated duodenum.</p><p><b>CONCLUSION</b>Ethanol extraction is an efficient method to extract the active constituents of BXN. BXN extract demonstrated multiple pharmacological activities affecting the main mechanisms of diarrhea, which validated BXN's usage in the comprehensive clinical treatment of diarrhea.</p>

Relationship between TIM-4 polymorphism and childhood asthma / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To elucidate whether the polymorphism of asthma immune regulator gene TIM-4 is associated with the risk of childhood allergic asthma in the southwest region of China.</p><p><b>METHODS</b>TIM-4 gene promoter region RS6882076 and intron RS4704727 were studied. PCR-RFLP was used to test the genotypes of two polymorphism loci among 579 cases (average 7.2 years old) of asthma and 524 controls (average 7.6 years old) in a case-control study.</p><p><b>RESULTS</b>There were significant differences in the frequency of gene types at RS4704727 site between the asthma and the control groups (P<0.01). The results of PCR-RFLP showed that the polyporphisms of RS6882076 and RS4704727 in TIM-4 gene were present in this study population. The frequency of T allele at the RS4704727 site in the asthma group was significantly lower than that in the control group (OR=1.603; 95%CI 1.304-1.971; P<0.01). There were no significant differences in the frequencies of gene types and allele at RS6882076 site between the two groups (P>0.05).</p><p><b>CONCLUSIONS</b>RS4704727 polymorphism of TIM-4 gene may be associated with childhood asthma, providing a better understanding of the pathogenesis of childhood asthma in the Southwest region of China.</p>

Analysis of gag-specific IFN-gamma secretion responses in HIV-1 B/C recombinant infectors / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To characterize the Gag-Specific T lymphocyte responses and identify immunodominant region recognized in Chinese HIV-1 recombinant subtype B/C infectors.</p><p><b>METHODS</b>10 antiretroviral treatment (ART) naive HIV-1 recombinant subtype B/C infectors with infected time in 1 year, 25 ART-naive infectors with infected time > 3 years and 10 HIV-1-seronegative healthy individuals were enrolled. HIV-1-specific T lymphocyte responses were analyzed by an IFN-gamma Elispot assay against 123 overlapping peptides spanning HIV-1 Gag protein in the present study.</p><p><b>RESULTS</b>Gag-specific T lymphocyte responses of interferon-gamma secretion were identified in 8(8/10) Chinese HIV-1 recombinant subtype B/ C infectors with infected time in 1 year, the specific T lymphocytes are mainly targeted at five seperated peptides. Responses were identified in 17(68%) infectors with infected time more than 3 years, the specific T lymphocytes are mainly targeted at one peptide in p17 and six in p24. There was obviously positive correlation (P = 0.0318, r = 0.519) between the magnitude of responses and viremia in infectors infected time > 3 years. The magnitude of response in infectors infected in 1 year was significantly higher than group infected time > 3 years (P = 0.021). None of healthy individuals produced positive responses.</p><p><b>CONCLUSIONS</b>HIV-1 recombinant subtype B/C Infectors at different stages of diseases recognize different region of gag.</p>

Construction of the eukaryotic expression plasmid containing lvgA gene flanked with CpG motifs of Legionella pneumophila and its expression in NIH3T3 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct the eukaryotic expression plasmid containing lvgA gene flanked with CpG motifs of Legionella pneumophila for its expression in NIH3T3 cells.</p><p><b>METHODS</b>lvgA gene flanked with CpG motifs of Legionella pneumophila was amplified by PCR. The PCR products was inserted into the eukaryotic expression plasmid pcDNA3.1/myc-his(+) to construct the recombinant plasmid pclvgA/CpG, which was subsequently transfected into NIH3T3 cells via lipofection. Immunofluorescence analysis was carried out to detect the transient expression of the plasmid in the cells.</p><p><b>RESULTS</b>Sequence analysis showed that the recombinant plasmid pclvgA/CpG contained the lvgA/CpG fragment with a length of 657 bp, encoding a protein of 27.7 Ku. Immunofluorescence analysis identified the transient expression of the recombinant plasmid pclvgA/CpG in NIH3T3 cells.</p><p><b>CONCLUSION</b>The lvgA gene flanked with CpG motifs of Legionella pneumophila has been constructed successfully, and the transient expression of the recombinant plasmid pclvgA/CpG can be detected in NIH3T3 cells.</p>

Comparison of the quantities and subset distributions of natural killer cells among different races / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Natural killer (NK) cells play critical roles in host immune defense, while the quantities and subset distributions may vary among different races. To address the difference, we compared these variables among Chinese Han, the Caucasians and the Blacks. The study may provide critical background information for both basic research and clinical investigation.</p><p><b>METHODS</b>Blood samples collected from populations of different races were tested within 12 hours after collection and subsets of NK cells were characterized using flow cytometry.</p><p><b>RESULTS</b>The absolute NK count in the Chinese Han was significantly higher than that in the Caucasian. The Han and Caucasian groups showed higher percentages of cytotoxic subset compared to that of the Black group. The percentage of cytokine-producing subset of Chinese Han group was lower than that of Caucasian and Black groups. Black group had a higher percentage of function-unknown NK subset than that of the Han and Caucasian groups.</p><p><b>CONCLUSION</b>Our data indicated that NK cell count and the distribution of different subsets varied among different races, which should be taken into consideration in related investigations.</p>

Complete human immunodeficiency virus-1 specific T lymphocyte response to Chinese human immunodeficiency virus-1 B/C chronic infectors / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To characterize the human immunodeficiency virus (HIV) -specific T lymphocyte responses and identify the immunodominant regions in Chinese HIV-1 recombinant subtype B/C chronic infectors at complete genome level.</p><p><b>METHODS</b>Twenty-five HIV-1B/C recombinant chronic infectors were screened for their specific T lymphocyte responses to a panel of peptides corresponding to the complete HIV-1 subtype B genome by gamma interferon ELISPOT assay. Kruskal-Wallis nonparametric analysis of variance was used to test significant differences across gene regions, and Tukey pairwise analysis was used to identify differences between gene regions. Spearman rank correlation was used to assess the relation between responses. Results The order of recognized frequencies of specific T lymphocyte responses to HIV proteins was Nef>Vpr>Gag>Pol>Vpu>Env>Rev>Vif>Tat. When adjusted for protein length, Nef, Vpr, Gag, and Pol were the most intensely targeted proteins and the central region of Nef, Gag p24, Pol RT, and Vpr was most frequently recognized. No significant correlation was observed between the magnitude of IFN-gamma production of HIV-l-specific T lymphocyte responses and plasma viremia, breadth of response and CD4 counts. Conclusion The central region of Nef, Gag p24, Pol RT, and Vpr is most frequently targeted in HIV-1 B/C recombinants chronic infectors. HIV-l-specific T lymphocyte responses and plasma viremia or CD4 counts play no protective role at complete genome level in these infectors.</p>

Genetic variation of gag gene in HIV-1 subtype B infections from Henan and Shanxi provinces of China / 病毒学报

The 109 whole blood samples were collected from HIV-1 infected former blood donors in Henan and Shanxi. The RNA templates were extracted from plasma and used for the full gag gene amplification and sequencing. The sequences were divided into 3 groups according to sampling year. The Entropy software was used to identify the amino acids with composition difference among different groups of amino acid sequences. The results showed that there existed 8 and 13 amino acid sites with the statistical significance difference, respectively, in sequences in year 2004 and 2005, compared to those in 2002. Among them, there existed 5 amino acid sites in two groups. Of 16 amino acid sites, the increasing polymorphism and the decreasing polymorphism along the sampling year were observed in 10 and 6 amino acid sites respectively. Of 10 sites with increased polymorphism, 8 sites were located in the CTL epitopes recognized and presented by the main HLA alleles existed in Chinese population. The 6 sites with decreasing polymorphism all existed in main domains of Gag proteins.

T cell receptor diversity of CD8+ T lymphocytes and its association with viral load in individuals with HIV-1 infection / 中华预防医学杂志

<p><b>OBJECTIVE</b>To determine the complementary determining region 3 (CDR3) length diversity of T cell receptor Vbeta repertoires of CD8+ T lymphocytes and to explore its association with viral load in individuals with HIV-1 infection.</p><p><b>METHODS</b>Separation of CD8+ T cells from peripheral blood mononuclear cells (PBMCs) was carried out by using immunomagnetic beads coated with anti-CD8 antibody. Total RNAs from the purified CD8+ T lymphocytes were isolated and used to perform polymerase chain reaction (PCR) amplifications in CDR3 of 22 T cell receptor (TCR) gene families. CDR3 diversity and its association with viral load in individuals with HIV-1 infection were analyzed.</p><p><b>RESULTS</b>An average diversity for all CDR3 profiles in CD8+ T cells from 9 HIV-infected individuals was significantly different as compared to 7 age-matched healthy donors (P<0.05) with the HIV-infected individuals losing diversity in the CDR3 profiles. There was positive correlation between changes in TCR CDR3 diversity and viral load (r=0.771, P<0.05). The changes in CDR3 length diversity of Vbeta families in HIV-infected individuals, particular in Vbeta2, Vbeta4, Vbeta5, Vbeta17, Vbeta20, Vbeta21, Vbeta23, Vbeta24, were statistically different from the healthy controls.</p><p><b>CONCLUSION</b>HIV-1 infection might induce the loss of TCR Vbeta repertoire diversity and disrupt the CDR3 distributions within CD8+ T cells. There should be positive correlation between changes in TCR CDR3 diversity and the viral load in HIV-1 infected patients.</p>

CTL responses to regulatory proteins Tat and Rev in HIV-1 B'/C virus-infected individuals / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To characterize HIV-1 specific CTL responses to regulatory proteins Tat and Rev in HIV-B'/C virus-infected ART-naive individuals.</p><p><b>METHODS</b>HIV-1-specific CTL responses were analyzed by IFN-gamma ELISPOT assay using overlapping peptides spanning the consensus sequences of HIV-1 clade C Tat and Rev proteins. Statistical analysis and graphical presentation were performed using SIGMAPLOT 10.0 and SIGMASTAT 3.5. For samples with a positive response, the magnitude of CTL responses was compared between HIV-1 C proteins by Wilcoxon rank sum test, and the significance threshold was P<0.05.</p><p><b>RESULTS</b>Tat and Rev were frequently recognized, with 23% and 52% of the tested individuals having detectable responses to these proteins, respectively. Several immunodominant regions were detected in Rev. No significant correlation was observed between the magnitude and breadth of CTL responses to regulatory proteins and the control of virus replication in this study.</p><p><b>CONCLUSION</b>Tat and Rev can serve as targets for HIV-1-specific CTL, and several immunodominant regions are detectable in Rev. Further characterization of epitopes and their role in virus control may shed light on pathogenesis of HIV-1 natural infection and also be useful for the design and testing of candidate vaccines.</p>

Relationship of HLA-A, -Cw Polymorphisms with HIV/AIDS in Chinese Yi Ethnic Group of Sichuan Province / 中国病毒学

The relationship of HLA-A, -Cw alleles on HIV infection and AIDS disease progression in the Chinese Yi ethnic group of Sichuan province were investigated. The genetic polymorphisms of HLA-A, -Cw alleles of 102 unrelated healthy Chinese Yi ethnic individuals, 68 HIV-1 infected and 21 HIV positive long-time survivors were typed by PCR-SSP assay. Statistic signifiance was determined by the χ2 test with the SPSS software. No significant differences were observed between the HLA-A, -Cw alleles of the 68 HIV-1 infected and 102 non-infected Chinese Yi control individuals. Whereas the prevalence of A*3601,Cw*14(01-03)and Cw*0304 was significantly higher in 21 long time survivors compared with 102 healthy controls with P values of 0.016, 0.016 and 0.000 by χ2 or the Fisher exact test respectively. The result implies that A*3601,Cw*14(01-03) and Cw*0304 may be associated with slow AIDS disease progression in the Chinese Yi ethnic group, further studies on this association may yield insight on the pathogenesis of HIV-1 infection.

Complete Genomic Sequence of a Chinese Isolate of Duck Hepatitis Virus / 中国病毒学

The complete genomic sequence of Duck hepatitis virus 1 (DHV-1) ZJ-V isolate was sequenced and determined to be 7 691 nucleotides (nt) in length with a 5'-terminal un-translated region (UTR) of 626 nt and a 3'-terminal UTR of 315 nt (not including the poly(A) tail). One large open reading frame (ORF) was found within the genome (nt 627 to 7 373) coding for a polypeptide of 2 249amino acids. Our data also showed that the poly (A) tail of DHV-1 has at least 22 A's. Sequence comparison revealed significant homology (from 91.9% to 95.7%) between the protein sequences of the virus in the Picornaviridae family, its genome showed some unique characteristics. DHV-1 contains 3copies of the 2A gene and only 1 copy of the 3B gene, and its 3'-NCR is longer than those of other picornaviruses. Phylogenetic analysis to do sequence homology based on the VP1 protein sequences showed that the ZJ-V isolate shares high sequence homology with the reported DHV-1 isolates (from 92.9% to 99.2%), indicating that DHV-1 is genetically stable.

Construction of rabbit hemorrhagic disease virus replicons and its replication in RK-13 cells / 病毒学报

To provide an efficient and safe technology platform for studying the replication and pathogenesis mechanisms of RHDV, the interaction between the RHDV and its host cells, a replicon system of RHDV, was constructed based on the infectious cDNA clone of RHDV, in which VP60 gene encoding the capsid protein was deleted, but all the necessary protease coding regions and non-coding regions were retained. Results from RT-PCR, IFA and qRT-PCR confirmed that the replicon RNA could efficiently replicate in RK-13 cells. Besides, the results also suggested that the capsid protein which is the structural protein of RHDV is necessary for maintaining the viral infectivity.

Preparation of recombinant Mycobacterium tuberculosis ESAT6-PPE68 fusion protein / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct esat6-ppe68 fusion gene and its prokaryotic expression vector for expression in E. coli.</p><p><b>METHODS</b>With GeneSOEing method, a fusion gene was constructed by splicing esat6 gene and ppe68 gene and cloned into pGEX-4T-1 plasmid to construct the recombinant prokaryotic expression plasmid pGesat6-ppe68. After identification with restriction enzyme analysis, PCR and nucleotide sequencing analysis of the plasmid, E. coli BL21 was transformed with the recombinant plasmid and induced with IPTG to obtain the expression of the fusion protein ESAT6-PPE68 with GST-tag (about 69 kD), which were purified with GST-fusion protein purification kit. The expression of esat6-ppe68 fusion gene was subsequently detected by SDS-PAGE and Western blot analysis.</p><p><b>RESULTS</b>The sequence of esat6 and ppe68 in the recombinant plasmid was consistent with that in GenBank report. The fusion protein was detected in the cytoplasm in soluble form and represented approximately 40% of the total bacterial protein of E. coli. After purification, the purity of the fusion protein reached 90%, and its antigenicity was confirmed by Western blotting.</p><p><b>CONCLUSION</b>The prokaryotic expression vector pGesat6-ppe68 has been constructed and the fusion protein ESAT6-PPE68 obtained successfully, which provides an experimental basis for potential application of the recombinant ESAT6-PPE68 in the diagnosis of tuberculosis.</p>

In vitro expression of Lgeionella pneumophila pilE gene and its immunogenicity / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a recombinant plasmid containing Lgeionella pneumophila pilE gene, detect its expression in NIH3T3 cells and evaluate its immunogenicity.</p><p><b>METHODS</b>PilE gene (LP) was amplified from Legionella pneumophila DNA by PCR and inserted into pcDNA3.1(+) vector to construct the recombinant plasmid pcDNA3.1-pilE, which as verified by restriction endonuclease digestion, PCR and DNA sequencing analysis. NIH3T3 cells were transfected with the recombinant plasmid with Lipofection strategy. Transient and stable pilE gene products were detected by immunofluorescence and Western blotting, respectively. To evaluate the immunogenicity of pcDNA3.1-pilE, the recombinant plasmid was used as a DNA vaccine to immunize female BALB/c mice intramuscularly and the specific antibodies, lymphocyte proliferation response, interferon (IFN)-gamma production and cytotoxic T-lymphocyte response of the immunized mice were detected and evaluated.</p><p><b>RESULTS</b>The pilE gene of 429 bp in length was amplified. After transfection of NIH3T3 cells with the recombinant plasmid, strong green fluorescence was observed on the cell membrane and inside the cell. A protein with relative molecular mass of 15.7 kD was detected in the transfected cells with Western blotting, suggesting successful protein expression of pilE gene. pcDNA3.1-pilE resulted in much stronger immune response in the immunized mice than pcDNA3.1(+) (P<0.01).</p><p><b>CONCLUSION</b>The recombinant plasmid containing Lgeionella pneumophila pilE gene constructed in this study is capable of expression in NIH3T3 cells, and can induce specific humoral and cellular immune responses in mice.</p>