Distribution and location of Daxx in cervical epithelial cells with high risk human papillomavirus positive.

AIMS: To provide the basis for further exploring the effect and its mechanism of Death domain associated protein (Daxx) on the progress of cervical carcinoma induced by human papillomavirus (HPV), the distribution and location of Daxx in cervical carcinoma with high risk HPV(HR-HPV) positive was analyzed. METHODS: The samples of normal cervical epithelial cells, cervical intraepithelial neoplasia grade I (CINI), CINII CINIII and cervical cancers were collected. Immunohistochemistry assay was used to analyze the distributions and locations of Daxx in the cervical tissue. Indirect immunoinfluorescence test was utilized to observe the locations of Daxx in Caski cells with HPV16 positive. RESULTS: Under the light microscopy, the brown signals of Daxx distributed in the nuclei of normal cervical epithelial cells; Daxx mainly distributed in nuclear membrane and there were a small amount of Daxx in the nuclei in CINI. Daxx intensively distributed in the cytoplasm and cell membrane in CINII, CINIII and cervical cancer. Under fluorescent microscopy, the distribution and location of Daxx in Caski cells was similarly to that in cervical cells of CINII, CINIII and cervical cancer. CONCLUSION: In the progress of the cervical cancer, Daxx gradually translocates from nucleus into nuclear membrane, cytoplasm and cell membrane. Daxx locates in the cytoplasm and cell membrane in CINII, CINIII and cervical cancer. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here:http://www.diagnosticpathology.diagnomx.eu/vs/4671548951113870.

Heme oxygenase-1 system, inflammation and ventilator-induced lung injury.

Mechanical ventilation is an indispensable supportive intervention for acute respiratory failure. However, mechanical ventilation can provoke ventilator-induced lung injury, which remains one of the major causes of morbidity and mortality in critically ill patients. Excessive inflammatory response characterized by infiltration of inflammatory cells and overproduction of inflammatory mediators contributes to the pathogenesis of ventilator-induced lung injury. At present, apart from the protective ventilation strategy, no other pharmacological intervention is available to attenuate ventilator-induced lung injury. Heme oxygenase-1 (HO-1) is the inducible isoform of the first and rate-limiting enzyme which degrades heme into carbon monoxide, ferritin and bilirubin. Accumulating evidence suggests that HO-1 system may function as a crucial negative regulator in the modulation of inflammatory process. This anti-inflammatory action of HO-1 is mediated essentially by the regulation of the key cells involved in inflammation and restoration of the balance between pro-inflammatory and anti-inflammatory mediators. Therefore, HO-1 system represents a promising therapeutic target for intervention of ventilator-induced lung injury.

In vitro activities of erythromycin, tetracycline and levofloxacin alone and in dual combinations against ureaplasma spp.

PURPOSE: It was the aim of our study to evaluate the in vitro activities of tetracycline (TET), erythromycin (ERY) and levofloxacin (LVX) alone and in dual combinations against ureaplasmas. METHODS: The minimum inhibitory concentrations (MICs) of 51 ureaplasmal strains were determined by microdilution assay. RESULTS: TET was the most active when the antibiotics were used alone. The combinations resulted in significantly decreased MICs for every agent compared with the use of single antibiotics (p < 0.05, respectively), except for ERY in the ERY-LVX pair (p > 0.05), and decreased the MICs more significantly in the strains with an MIC ≥4 mg/l compared with MIC <4 mg/l, except for the TET-ERY pair. The ERY-LVX pair increased ERY MICs significantly in the MIC <4 mg/l group (p < 0.05). The combinations resulted in more beneficial MICs in strains where both agents had an MIC ≥4 mg/l compared with those where either had an MIC ≥4 mg/l, as well as in strains where either agent had an MIC <4 mg/l compared with those where both had an MIC <4 mg/l. CONCLUSIONS: Drugs in dual combinations always give more beneficial MICs against ureaplasmas than one agent alone. Combinational benefits prefer strains with a higher initial MIC.

[Effect of over expression of HPV18 E2 protein on apoptosis and secretion of macrophages].

AIM: To study the effect of the over expression of GFP-E2, GFP-TAD(N-extremity domain of HPV18 E2) and GFP-DBD (C-extremity domain of HPV18 E2) on the apoptosis and secretion of macrophages and to further explore the contribution of E2 gene to the uterine cervix cancer. METHODS: TAD or DBD gene was amplified from pEGFP-C1/HPV18 E2 by PCR respectively and then cloned into pEGFP-C1 vector. After the transfection of recombinant plasmids or pEGFP-C1 into the macrophages, their expression was examined by fluorescent microscopy and Western blot. The cytokine content of TNF-alpha or IL-1alpha in the culture medium was tested quantitatively with ELISA kit respectively. The stained macrophages were observed and their apoptosis rate was tested by flow cytometry. RESULTS: After transfected into macrophages, GFP-E2 fusion protein was mainly located in cytoplasma while GFP-DBD fusion protein was completely located in nuclei and GFP-TAD fusion protein was completely located in cytoplasma. The overexpression of GFP-E2 or GFP-TAD increased the level of TNF-alpha and IL-1alpha and upregulate the apoptosis rate of macrophages. Furthermore, the effect of GFP-TAD was obvious except on IL-1beta level but the overexpression of GFP-DBD did not show the same effect. CONCLUSION: The overexpression of GFP-E2 or GFP-TAD fusion protein can induce the apoptosis macrophages and upregulate TNF-alpha or IL-1beta secretion of macrophages.

[Expression of inducible nitric oxide synthase was regulated by activating nuclear factor kappaB in mouse macrophages stimulated with ureaplasma urealyticum lipid-associated membrane proteins].

The aim was to investigate the molecular mechanisms responsible for the inducible nitric oxide synthase (iNOS) gene expression stimulated by lipid associated membrane proteins (LAMPs) of Ureaplasma urealyticum (Uu). Mouse macrophages were stimulated by Ureaplasma urealyticum LAMPs to analyze the production of nitric oxide (NO) and the expression of iNOS detected by RT-PCR and Western blot. The activation of NF-kappaB was examined in mouse macrophages treated with LAMPs by indirect immunofluorescence (IFA), immunocytochemistry and Western blot. The effects of pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappaB and of cycloheximide (CHX), a protein synthase inhibitor, on the expression of iNOS and on the activation of NF-kappaB were also investigated in mouse macrophages treated with LAMPs. Results showed Ureaplasma urealyticum LAMPs stimulated mouse macrophages to express iNOS and thus produce NO in dose- and time-dependent manners by activating nuclear factor kappaB. The activation of NF-kappaB and the expression of iNOS were inhibited by LAMPs combination with PDTC or CHX. In conclusion, these findings suggested Ureaplasma urealyticum may be an important pathogenic factor due to the ability of LAMPs to stimulate the expression of iNOS, which is probably medicated by the activation of NF-kappaB.

[Cloning and expression of outer membrane protein gene Gpd from Treponema pallidum and preliminary studies on its immunogenicity in rabbits].

To construct the recombinant plasmid of Eukaryotic expression containing Gpd gene from Treponema Pallidum and study its immunogenicity in New Zealand White rabbits. Gpd gene was amplified from the genomic DNA of T. pallidum and cloned into appropriate site of pcDNA3. 1 ( + ) vector. After verified that the Gpd antigen gene could be expressed in HeLa cells by Western blot and immunocytochemistry, recombinant plasmids pcDNA3.1 ( + )-Gpd, control plasmid pcDNA3. 1 ( + ) or PBS buffer were administered in three groups of New Zeal and White rabbits. Booster immunizations were employed at 2-week interval for three times. ELISA was used for the quantitative detection of the specific antibody in the sera of rabbits. The proliferation response of spleen cells was detected by MTT assay. The results of the Western blot and immunocytochemistry showed that Gpd gene constructed in pcDNA3.1 ( + ) vector could express a fusion protein with a calculated molecular mass of 41kD in HeLa cells and react with positive blood serum from syphilis patients. The significant specific antibody IgG titers were observed and the highest titer was 1:1024 in rabbits after three times with pcDNA3.1 ( + )-Gpd. The proliferation response of spleen cells were significantly higher than that of rabbits injected with pcDNA3.1 ( + ) (p < 0.05). All above results establish a solid basis for future studying the biological activities of Gpd and benefit the development of the Syphilis DNA vaccine.

Activation of nuclear factor kappaB and induction of inducible nitric oxide synthase by lipid-associated membrane proteins isolated from Mycoplasma penetrans.

BACKGROUND: This study was designed to investigate the potential pathogenicity of Mycoplasma penetrans (M. penetrans) and its molecular mechanisms responsible for the induction of iNOS gene expression in mouse macrophages stimulated by lipid-associated membrane proteins (LAMPs) prepared from M. penetrans. METHODS: Mouse macrophages were stimulated with M. penetrans LAMPs to assay the production of nitric oxide (NO). The expression of inducible nitric oxide synthase (iNOS) was detected by RT-PCR and Western blotting. The activity of nuclear factor kappaB (NF-kappaB) and the effects of pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappaB, on the production of nitric oxide and the expression of iNOS were also assessed in mouse macrophages treated with M. penetrans LAMPs by indirect immunofluorescence and Western blotting. RESULTS: M. penetrans LAMPs stimulated mouse macrophages to produce nitric oxide in a dose- and time-dependent manner. The mRNA and protein levels of iNOS were also upregulated in response to LAMP stimulation and inhibited by PDTC treatment. M. penetrans LAMPs were found to trigger NF-kappaB activation, a possible mechanism for the induction of iNOS expression. CONCLUSION: This study demonstrated that M. penetrans may be an important etiological factor of certain diseases due to the ability of M. penetrans LAMPs to stimulate the expression of iNOS, which is probably mediated through the activation of NF-kappaB.

[Transferrin receptor expression of human mesenchymal stem cells and in vitro tracking by autoradiography after transplantation in spinal cord].

OBJECTIVE: To determine transferrin receptor (TfR) expression of human mesenchymal stem cells (MSCs) in vitro and after transplantation in rabbit spinal cord,and to detect implanted MSCs by in vitro autoradiography. METHODS: Human mesenchymal stem cells (hMSCs) were isolated from fetal blood. Flow cytometry assay, immuno-fluorescent staining and receptor binding assay were used to determine TfR expression of hMSCs. Radioiodinated transferrin saturated with iron [(125)I-Tf(Fe)(2)] was used as tracer. The hMSCs transplanted in rabbit spinal cord was tracked by in vitro autoradiography. Diffusion of (125)I-Tf(Fe)(2) in spinal cord was examined with autoradiography. RESULTS: TfR expression of MSCs was demonstrated by flow cytometry assay, immuno-fluorescent staining and receptor binding assay in vitro. (125)I-Tf(Fe)(2) bound to hMSCs with a equilibrium dissociation constant (KD) of (0.98+/-0.12) nmol/L and a maximal density of binding sites (B(max)) of (107 702+/-6 226) sites per cell. Immuno-fluorescent staining showed that TfRs were expressed on hMSCs on the 2nd day but not be expressed on the 10th day post transplantation. Autoradiography showed distinct accumulation of (125)I-Tf(Fe)(2) but not (125)I-HSA at hMSCs implantation sites of spinal cord sections on the 2nd day post transplantation. (125)I-Tf(Fe)(2) had diffused into spinal cord 16 hours after incubation. CONCLUSION: Implanted hMSCs could be detected by in vitro autoradiography with (125)I-Tf(Fe)(2) on the 2nd day after being transplanted in spinal cord. To track implanted hMSCs with radionuclide imaging techniques in vivo, TfR was a suitable target for imaging and radioiodinated Tf(Fe)(2) was a feasible tracer.

Transcriptional repression of hDaxx enhanced by adenovirus 12 E1B 55-kDa oncoprotein interacting with hDaxx.

BACKGROUND: Daxx has been identified as a nuclear protein that involves in apoptosis and transcriptional repression. Daxx co-localizes with the promyelocytic leukemia (PML) protein and regulates transcription. Human Daxx (hDaxx) is a protein that functions as a transcriptional regulation through its interaction with some DNA-associated proteins. The aim of this study was to explore the transcriptional regulatory effect of hDaxx interacting with adenovirus (Ad) 12 E1B (Ad12E1B) 55-kDa oncoprotein. METHODS: The co-localization of hDaxx-Ad12E1B or hDaxx-PML protein in the nucleus was observed under a confocal microscope. Interaction of hDaxx and Ad12E1B was analyzed by yeast two-hybrid assay. Direct binding of hDaxx and Ad12E1B was analyzed using coimmunoprecipitation and Western blot in vivo and in vitro. The activity of a luciferase reporter gene, which was regulated by an hDaxx modulated thymidine kinase (TK) promoter, was detected in an automat luminometer. RESULTS: Ad12E1B, which co-localized with hDaxx in the nuclei of G401-CC3 cells, disrupted the co-localization of hDaxx and PML in the PML oncogenic domains (PODs). hDaxx bound directly to Ad12E1B in vivo and in vitro. hDaxx interacted with Ad12E1B along its full length. Ad12E1B enhanced transcriptional repression activity of hDaxx. CONCLUSION: Ad12E1B disrupts the co-localization of hDaxx with PML in PODs and enhances transcriptional repression activity of hDaxx.