A point mutation in the DNA-binding domain of HPV-2 E2 protein increases its DNA-binding capacity and reverses its transcriptional regulatory activity on the viral early promoter.

Background: The human papillomavirus (HPV) E2 protein is a multifunctional DNA-binding protein. The transcriptional activity of HPV E2 is mediated by binding to its specific binding sites in the upstream regulatory region of the HPV genomes. Previously we reported a HPV-2 variant from a verrucae vulgaris patient with huge extensive clustered cutaneous, which have five point mutations in its E2 ORF, L118S, S235P, Y287H, S293R and A338V.

Investigation of the water purification efficiency of flood irrigation system by using flora succession as an index.

A flood irrigation system was constructed to remove nutrient-based water pollutants through the various natural treatment mechanisms of plants and microorganisms. Species of plants were allowed to proliferate naturally within the system. The succession of flora was then utilized as an index to evaluate the water purification efficiency of the flood irrigation system.

[The enhancement of DNA binding ability of a mutated E2 (A338V) protein of HPV-2].

HPV-2 is a very common type of HPV which causes common warts. The E2 protein of virus can repress the activity of the viral early promoter through binding to the specific binding sites in viral LCR. Previously we reported that the repression of a mutated E2 protein of HPV-2 isolated from a patient with huge common wart on the viral early promoter was obviously decreased, and A338V mutation located at the C terminal DNA binding region of E2 protein.

[Inactivation of bacterial spores using low-temperature plasma].

Objective: To investigate the effect of low-temperature plasma on inactivation of bacterial spores and explore the mechanism.

Methods: Dielectric barrier discharge (DBD) was employed to generate the atmospheric low-temperature plasma for treatment of B.subtilis var.

[Oral acute toxicity of (+)-usnic acid in mice and its cytotoxicity in rat cardiac fibroblasts].

Objective: To observe the oral acute toxicity of of (+)-usnic acid in mice and assess its cytotoxicity in rat cardiac fibroblasts.

Methods: The mice with acute poisoning of (+)-usnic acid at different doses by oral administration were observed for toxic manifestations, and the LD(50) was determined. The survival time and survival rate of the mice receiving different doses of (+)-usnic acid were observed.

Molecular epidemiological study on prevalence of human papillomaviruses in patients with common warts in Beijing area.

Objective: To study the circulation, distribution, and genomic diversity of HPVs in common warts in Beijing area of China.

Methods: Forty eight patients with pathologically diagnosed common warts were screened for the presence of HPV with HPV type-specific PCR and direct sequencing analysis. The genomic diversity of HPVs prevalent in Chinese patients was analyzed based on LCR.

[In vitro effect of (+)-usnic acid on Toxoplasma gondii tachyzoites].

Objective: To explore the effect of usnic acid on Toxoplasma gondii tachyzoites in vitro.

Methods: There are four groups named as (+)-usnic acid group, acetylspiramycin group, DMSO group and normal saline group. Groups of (+)-usnic acid and acetylspiramycin were further divided into 4 subgroups with final concentration of 5, 10, 25, 50 microg/ml respectively.

Nerve growth factor of red nucleus involvement in pain induced by spared nerve injury of the rat sciatic nerve.

Nerve growth factor (NGF), a member of the neurotrophin family, is essential for the development and maintenance of sensory neurons and for the formation of central pain circuitry. The current study was designed to evaluate the expression of NGF in the brain of rats with spared nerve injury (SNI), using immunohistochemical technique. The results showed that the level of NGF in the Red nucleus (RN) of SNI rats was apparently higher than that of sham-operated rats.

Evaluation of protective effect of multi-epitope DNA vaccine encoding six antigen segments of Toxoplasma gondii in mice.

To investigate the vaccine potential of multi-epitope vaccines against toxoplasmosis, a multi-epitope DNA vaccine, eukaryotic plasmid pcDNA3.1/T-ME expressing six antigen segments (SAG1(238-256), SAG1(281-320), GRA1(170-193), GRA4(331-345), GRA4(229-245), and GRA2(171-185)) of Toxoplasma gondii was constructed. We investigated the efficacy of pcDNA3.

[Transcriptional repressive activity of mutated E2 protein of human papillomavirus 2 (HPV-2) variant].

Common warts are close associated with HPVs infection. In this study, we amplified and sequenced the LCR fragment and E2 gene of HPV-2 that infected the patient of extensive common wart with cutaneous horns, and we constructed the recombinant CAT-reporter plasmids pBLCAT-LCR containing HPV-2 prototype or variant LCR and mammalian expression plasmids pcDNA3. 1-E2 containing prototype or variant E2 ORF individually.

[Construction of multi-epitope DNA vaccine for Toxoplasma gondii and the study on protective immunity response in mice].

Aim: To construct multi-epitope DNA vaccine for Toxoplasma gondii and study its protective immunity response.

Methods: The gene encoding six polypeptides of T. gondii, which consists of plenty of T and B epitopes, was cloned into the eucaryotic expression vector pcDNA3.

Mu-opioid receptor in the nucleus submedius: involvement in opioid-induced inhibition of mirror-image allodynia in a rat model of neuropathic pain.

The current study investigated the roles of various subtypes of opioid receptors expressed in the thalamic nucleus submedius (Sm) in inhibition of mirror-image allodynia induced by L5/L6 spinal nerve ligation in rats. Morphine was microinjected into the Sm, which produced a dose-dependent inhibition of mirror-image allodynia; this effect was antagonized by pretreatment with non-selective opioid receptor antagonist naloxone. Microinjections of endomorphin-1 (mu-receptor agonist), or [D-Ala(2), D-Leu(5)]-enkephalin (DADLE, delta-/mu-receptor agonist), also inhibited mirror-image allodynia, and these effects were blocked by the selective mu-receptor antagonist, beta-funaltrexamine hydrochloride.

[Bactericidal activity of GLL-37, a novel derivative of the human antimicrobial peptide LL-37].

Objective: To develop and investigate GLL-37, a substitution analogue of the human antimicrobial peptide LL-37 with anti-enzymatic degradation activity and improved efficacy.

Methods: The bactericidal activities of LL-37 and newly developed GLL-37 against 6 Gram-negative and -positive bacteria were determined by Broth microdilution assays. The minimum inhibitory concentrations of LL-37 and GLL-37 against E.

Development of a multiplex PCR method for detecting and typing human papillomaviruses in verrucae vulgaris.

The methods for detecting and typing human papillomavirus (HPV) in most molecular epidemiological surveys of verrucae vulgaris were based on PCR followed by sequencing or hybridization. However, the amplification efficacies of different assays for the detection of HPV DNAs varied largely. In this study, a novel multiplex PCR method to detect and type the HPVs (HPV-1, -2, -27 and -57) related to verrucae vulgaris was described.

HPV-2 isolates from patients with huge verrucae vulgaris possess stronger promoter activities.

Objectives: To assess the influences of the mutations within the long control region (LCR) and E2 open reading frame (ORF) of the human papillomavirus-2 (HPV-2) isolates from patients with extensive verrucae vulgaris with cutaneous horns in the activities of the viral early promoters.

Methods: A PCR method was applied for screening HPV DNA in the lesion specimens and the complete HPV-2 genomes was analyzed. Recombinant CAT-reporter plasmids containing various HPV-2 LCRs and mammalian expression plasmids containing E2 ORF were constructed.

[Analgesic effect of interleukin-2 in mouse models of spared nerve injury].

Objective: To investigate the analgesic effect of interleukin-2 (IL-2) in mice with spared nerve injury (SNI).

Method: IL-2 was intraperitoneally injected in mice with induced SNI, and von Frey Filaments test and cold plate test were carried out to accesses the analgesic effects of IL-2 and the effect of naloxone in antagonizing the effects of IL-2.

Results: IL-2 produced analgesic effects against hyperalgesia and allodynia in mouse models of SNI, and the effect of IL-2 lasted for more than 24 h, showing a double-peak pattern in its action with the two peaks occurring at 30 and 105 min, respectively.

Resveratrol induces apoptosis, influences IL-6 and exerts immunomodulatory effect on mouse lymphocytic leukemia both in vitro and in vivo.

Resveratrol, a dietary polyphenol found in grapes, has been proposed to act as a chemopreventive or anti-tumor agent in numerous epidemiologic studies. In this study, we investigate the antitumor and immunomodulation effects of resveratrol on mouse lymphocytic leukemia cells L1210 both in vitro and in vivo. Our finding indicates that resveratrol inhibits proliferation, induces apoptosis, and influences cell cycle of L1210 cells in a dose- and time-dependent manner in vitro.

Effective induction of type 1 cytotoxic T cell responses in mice with DNA vaccine encoding two hepatitis C virus cytotoxic T lymphocyte epitopes.

The aims of this study were to explain whether a multiple cytotoxic T lymphocyte (CTL) epitope-based anti-hepatitis C virus (HCV) DNA vaccine can induce specific CTL responses to each HCV CTL epitope independently and long-term CD8(+) T cell memory responses, and to determine the cytokine secretion pattern and subtype of epitope-specific cytotoxic T cells. A multi-CTL epitope gene, which consists of two epitopes of HCV (H-2(d)-restricted HCV core(133142) and E1(315322)), was cloned into the eukaryotic expression vector pcDNA3.1.

[Inducement of cytotoxic T cell responses in mice by constructing a multi-CTL epitope-based DNA vaccine].

Aim: To construct a multi-CTL epitope-based DNA vaccine to induce specific CTL responses.

Methods: Multi-CTL epitope gene which encoded two HCV epitopes(H-2(d)) was cloned into the eucaryotic expression vector pcDNA3.1 to construct a multi-CTL epitope-based DNA vaccine.

Study on the relationship between level of CD58 expression in peripheral blood mononuclear cell and severity of HBV infection.

Background: As one of the intercellular adhesion molecules, CD58 plays important roles in promotion of the adhesion between T cells and target cells, hyperplasia, activation of T cells and natural killer cells, and balance between Th1 and Th2. We studied the relationship between the levels of CD58 expression in peripheral blood mononuclear cells (PBMCs) and severity of HBV infection.

Methods: The levels of CD58 mRNA in PBMCs were detected using quantitative reverse transcription PCR.

mu- but not delta- and kappa-opioid receptor mediates the nucleus submedius interferon-alpha-evoked antinociception in the rat.

Previous studies have indicated that interferon-alpha (IFN-alpha) can bind to opioid receptors and exerts an antinociceptive effect in both peripheral and central nervous systems. The current study investigated the antinociceptive effect of IFN-alpha unilaterally microinjected into the thalamic nucleus submedius (Sm) of rats on noxious thermal stimulus, and the roles of different subtypes of opioid receptors in mediating the Sm IFN-alpha-evoked antinociception. The results indicated that unilateral microinjection of IFN-alpha (4, 8, 16 pmol) into the Sm dose-dependently increased the hind paw withdrawal latency from the noxious heat stimulus, and this effect was reversed by pretreatment with non-selective opioid receptor antagonist naloxone (200 pmol) and specific mu-opioid receptor antagonist beta-FNA (1 nmol) into the same sites, whereas delta-opioid receptor antagonist ICI174,864 (1 nmol) and kappa-opioid receptor antagonist nor-BNI (1 nmol) failed to alter the effect of IFN-alpha.

[Preliminary study on anti-tumor function of resveratrol and its immunological mechanism].

Aim: To explore the immunological mechanism of the anti-tumor function of resveratrol (Res) through in vitro or vivo experiments.

Methods: The tumor cell growth repression rate was measured by MTT colorimetry. Flow cytometry was used to analyze the cell cycle of Hep2 cells (laryngeal squamous cancer cell line).

[Effects of allogeneic hepatic nonparenchymal cell on the survival of grafted skin in mice].

Objective: To investigate the effect of allogene hepatic nonparenchymal cell (NPC) on the survival of grafted skin in mice and its underlying mechanism.

Methods: Sixty-five C(3)H and fifty-eight C(57)BL/6 mice were employed in the study. Twenty C(3)H mice were used as skin donor and forty as the source of hepatic NPC.

[Construction and identification of recombinant adenovirus vector harboring CTLA4Ig-IRES 2-Ikappa-Balpha gene in ECV-304 cells].

Aim: To construct adenovirus vector harboring CTLA4Ig-IRES 2-IkappaBalpha gene,and investigate its expression in ECV304 cells.

Methods: Recombinant adenovirus vector harboring CTLA4Ig-IRES 2-IkappaBalpha was constructed by homologous recombination in E.coli BJ5183.