Mechanism of nuclear factor of activated T-cells mediated FasL expression in corticosterone -treated mouse Leydig tumor cells

<p>Abstract</p> <p>Background</p> <p>Fas and FasL is important mediators of apoptosis. We have previously reported that the stress levels of corticosterone (CORT, glucocorticoid in rat) increase expression of Fas/FasL and activate Fas/FasL signal pathway in rat Leydig cells, which consequently leads to apoptosis. Moreover, our another study showed that nuclear factor of activated T-cells (NFAT) may play a potential role in up-regulation of FasL during CORT-treated rat Leydig cell. It is not clear yet how NFAT is involved in CORT-induced up-regulation of FasL. The aim of the present study is to investigate the molecular mechanisms of NFAT-mediated FasL expression in CORT-treated Leydig cells.</p> <p>Results</p> <p>Western blot analysis showed that NFAT2 expression is present in mouse Leydig tumor cell (mLTC-1). CORT-induced increase in FasL expression in mLTC-1 was ascertained by Western Blot analysis and CORT-induced increase in apoptotic frequency of mLTC-1 cells was detected by FACS with annexin-V labeling. Confocal imaging of NFAT2-GFP in mLTC-1 showed that high level of CORT stimulated NFAT translocation from the cytoplasm to the nucleus. RNA interference-mediated knockdown of NFAT2 significantly attenuated CORT-induced up-regulation of FasL expression in mLTC. These results corroborated our previous finding that NFAT2 is involved in CORT-induced FasL expression in rat Leydig cells and showed that mLTC-1 is a suitable model for investigating the mechanism of CORT-induced FasL expression. The analysis of reporter constructs revealed that the sequence between -201 and +71 of mouse FasL gene is essential for CORT-induced FasL expression. The mutation analysis demonstrated that CORT-induced FasL expression is mediated via an NFAT binding element located in the -201 to +71 region. Co-transfection studies with an NFAT2 expression vector and reporter construct containing -201 to +71 region of FasL gene showed that NFAT2 confer a strong inducible activity to the FasL promoter at its regulatory region. In addition, chromatin immunoprecipitation assay further confirmed the results of reporter gene studies by showing the specific binding of NFAT2 to the -201 to +71 region.</p> <p>Conclusion</p> <p>In the present study, we demonstrated that NFAT2 directly stimulates transcription of FasL in high level CORT-treated mLTC-1. In conclusion, the present study provides further evidence for our finding that CORT-induced FasL expression in Leydig cells is mediated by NFAT.</p

miR-1908 as a novel prognosis marker of glioma via promoting malignant phenotype and modulating SPRY4/RAF1 axis

MicroRNAs (miRNAs) are reported to be involved in the development of glioma. However, study on miRNAs in glioma is limited. The present study aimed to identify miRNAs which can act as potential novel prognostic markers for glioma and analyze its possible mechanism. We show that miR-1908 correlates with shorter survival time of glioma patients via promoting cell proliferation, invasion, anti-apoptosis and regulating SPRY4/RAF1 axis. Analysis of GEO and TCGA database found that miR-1908 was significantly upregulated in glioma tissues, and strongly associated with shorter survival time of glioma patients. Further Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that miR-1908 is mainly involved in regulating cell proliferation, invasion and apoptosis. To further confirm the above results, in vitro, glioma U251 cells were transfected with miR-1908 mimics or inhibitor, and upregulated miR-1908 promoted U251 cell proliferation, and enhanced the ability of invasion by transwell assay. In addition, upregulated miR-1908 also enhanced anti-apoptosis ability of U251 cells through decreasing pro-apoptosis protein Bax expression. Since miRNAs regulate numerous biological processes by targeting broad set of messenger RNAs, validated target genes of miR-1908 in glioma were analyzed by Targetscan and miRTarBase databases. Among them SPRY4 was significantly decreased in glioma tissues and associated with short survival time, which was selected as the key target gene of miR-1908. Moreover, protein-protein interaction (PPI) showed that SPRY4 could interacted with pro-oncogene RAF1 and negatively correlated with RAF1 expression. Consistent with above analysis, in vitro, western blot analysis identified that miR-1908 upregulated significantly decreased SPRY4 expression and increased RAF1 expression. Hence, miR-1908 was correlated with poor prognosis of glioma via promoting cell proliferation, invasion, anti-apoptosis and regulating SPRF4/RAF1 axis. Our results elucidated the tumor promoting role of miR-1908 and established miR-1908 as a potential novel prognostic marker for glioma

Comparison of Resistance to γ-Irradiation between Cryptosporidium parvum and Cryptosporidium muris Using In Vivo Infection

In the genus Cryptosporidium, there are more than 14 species with different sizes and habitats, as well as different hosts. Among these, C. parvum and C. hominis are known to be human pathogens. As C. parvum can survive exposure to harsh environmental conditions, including various disinfectants or high doses of radiation, it is considered to be an important environmental pathogen that may be a threat to human health. However, the resistance of other Cryptosporidium species to various environmental conditions is unknown. In this study, resistance against γ-irradiation was compared between C. parvum and C. muris using in vivo infection in mice. The capability of C. muris to infect mice could be eliminated with 1,000 Gy of γ-irradiation, while C. parvum remained infective in mice after up to 1,000 Gy of γ-irradiation, although the peak number of oocysts per gram of feces decreased to 16% that of non-irradiated oocysts. The difference in radioresistance between these 2 Cryptosporidium species should be investigated by further studies

MRI features of breast lymphoma: preliminary experience in seven cases

PURPOSEWe aimed to evaluate the imaging features of breast lymphoma using magnetic resonance imaging (MRI). METHODSThis retrospective study consisted of seven patients with pathologically confirmed breast lymphoma. The breast lymphomas were primary in six patients and secondary in one patient. All patients underwent preoperative dynamic contrast-enhanced MRI and one underwent additional diffusion-weighted imaging (DWI) with a b value of 600 s/mm2. Morphologic characteristics, enhancement features, and apparent diffusion coefficient (ADC) values were reviewed.RESULTSOn MRI, three patients presented with a single mass, one with two masses, two with multiple masses, and one with a single mass and a contralateral focal enhancement. The MRI features of the eight biopsied masses in seven patients were analyzed. On MRI, the margins were irregular in six masses (75%) and spiculated in two (25%). Seven masses (87.5%) displayed homogeneous internal enhancement, while one (12.5%) showed rim enhancement. Seven masses (87.5%) showed a washout pattern and one (12.5%) showed a plateau pattern. The penetrating vessel sign was found in two masses (25%). One patient with two masses underwent DWI. Both masses showed hyperintense signal on DWI with ADC values of 0.867×10-3 mm2/s and 0.732×10-3 mm2/s, respectively.CONCLUSIONBreast lymphoma commonly presents as a homogeneously enhancing mass with irregular margins and displays a washout curve pattern on dynamic MRI. A low ADC value may also indicate a possible diagnosis of breast lymphoma

Fluoxetine Up-Regulates Bcl-xL Expression in Rat C6 Glioma Cells

Objective To analyze both differentially expressed genes and the Bcl-xL protein expression after acute and chronic treatment with fluoxetine in rat C6 glioma cells. Methods C6 glioma cells were cultured for 24 h or 72 h after treatment with 10 mu M fluoxetine, and gene expression patterns were observed using microarray and qRT-PCR. Then, cells were cultured for 6 h, 24 h, 72 h or 96 h after treatment with 10 mu M fluoxetine, and the expression of Bd-xL protein was measured using western blot. Results As determined by microarray, treatment with fluoxetine for 24 h up-regulated 33 genes (including Bcl-xL and NCAM140) and down-regulated 7 genes (including cyclin G-associated kinase). Treatment with fluoxetine for 72 h up-regulated 53 genes (including Gs alpha and Bcl-xL) and down-regulated 77 genes (including Gai2 and annexin V). Based on the qRT-PCR results, there was an increase in Gsa mRNA and a decrease in G alpha i2 mRNA at 72 h in fluoxetine-treated cells as compared to control, a result that was consistent with microarray. We also observed an increase in Bcl-xL mRNA (both at 24 h and at 72 h) in fluoxetine-treated cells as compared to control, demonstrating a tendency to increase gradually. Bcl-xL protein expression increased as the duration of fluoxetine treatment increased. Conclusion These results suggest that chronic treatment with fluoxetine not only initiates the cAMP pathway through inducing Gsa expression but also induces Bcl-xL expression, thus inhibiting apoptosis. Psychiatry Investig 2011;8:161-168This work was supported by the research fund of Hanyang University (HY-2010-N)

Risk Factors Associated with Head Louse Infestation in Korea

Head louse infestation (HLI) is one of the most frequently occurring parasitic diseases in children. This study was conducted to investigate the socioeconomic and personal factors influencing HLI in the Republic of Korea. A total of 2,210 questionnaires about various factors related to HLI were obtained from children in 17 primary schools throughout the country. The rate of HLI was significantly lower in children who lived together with mother or in a family where both parents worked. In addition, HLI was lower in children whose fathers or mothers were public officers or teachers. However, HLI was higher in children who had small families and washed their hair less often. Education levels of parents and the number of children in family were not significant. Improvement of socioeconomic factors and personal hygiene will be helpful for reducing HLI

Spin-phonon scattering-induced low thermal conductivity in a van der Waals layered ferromagnet Cr2_2Si2_2Te6_6

Layered van der Waals (vdW) magnets are prominent playgrounds for developing magnetoelectric, magneto-optic and spintronic devices. In spintronics, particularly in spincaloritronic applications, low thermal conductivity ($\kappa$) is highly desired. Here, by combining thermal transport measurements with density functional theory calculations, we demonstrate low $\kappa$ down to 1 W m$^{-1}$ K$^{-1}$ in a typical vdW ferromagnet Cr$_2$Si$_2$Te$_6$. In the paramagnetic state, development of magnetic fluctuations way above $T_\mathrm{c}=$ 33 K strongly reduces $\kappa$ via spin-phonon scattering, leading to low $\kappa \sim$ 1 W m$^{-1}$ K$^{-1}$ over a wide temperature range, in comparable to that of amorphous silica. In the magnetically ordered state, emergence of resonant magnon-phonon scattering limits $\kappa$ below $\sim$ 2 W m$^{-1}$ K$^{-1}$, which would be three times larger if magnetic scatterings were absent. Application of magnetic fields strongly suppresses the spin-phonon scattering, giving rise to large enhancements of $\kappa$. Our calculations well capture these complex behaviours of $\kappa$ by taking the temperature- and magnetic-field-dependent spin-phonon scattering into account. Realization of low $\kappa$ which is easily tunable by magnetic fields in Cr$_2$Si$_2$Te$_6$, may further promote spincaloritronic applications of vdW magnets. Our theoretical approach may also provide a generic understanding of spin-phonon scattering, which appears to play important roles in various systems.Comment: 14 pages, 6 figures, accepted for publication in Advanced Functional Material

Changes in Histopathological and Serological Findings of the Liver after Treatment in Rabbit Clonorchiasis

In order to elucidate the recovery course and the residual change of clonorchiasis after praziquantel treatment, the changing pattem of histopathological findings of the liver, along with the serological, biochemical and hematological parameters, were evaluated in experimental rabbit clonorchiasis. Twenty rabbits were infected each with 300 metacercariae of Clonorchis sinensis and treated with praziquantel 200 mg/kg 14 weeks after infection. Until one year after infection, a Widening of the bile ducts, proliferation of biliary epithelium, and periductal fibrosis were observed in the liver, although the lesions became much milder than those of the untreated rabbits. The levels of anti-e. sinensis IgG antibody in the sera by EUSA decreased continuously after treatment. Biochemical items and hematological parameters showed no consistent changing pattem after infection or after treatment. It can be suggested that the histopathological lesions of rabbit cionorchlais, i.e., duct dilatation, hyperplasia of biliary epithelium and periductal fibrosis, may be hardly reversible. However, the level of circulating specific IgG antibody decreased significantly according to the healing process of inflammation

Induction of defense-related enzymes in patchouli inoculated with virulent Ralstonia solanacearum

Background: Defense-related anti-oxidative response is a vital defense mechanism of plants against pathogen invasion. Ralstonia solanacearum is an important phytopathogen. Bacterial wilt caused by R. solanacearum is the most destructive disease and causes severe losses in patchouli, an important aromatic and medicinal plant in Southeast Asia. The present study evaluated the defense response of patchouli inoculated with virulent R. solanacearum. Results: Results showed that the basic enzymatic activities differed not only between the leaves and stems but also between the upper and lower parts of the same organ of patchouli. POD, SOD, PPO, and PAL enzymatic activities were significantly elevated in leaves and stems from patchouli inoculated with R. solanacearum compared to those in control. The variation magnitude and rate of POD, PPO, and PAL activities were more obvious than those of SOD in patchouli inoculated with R. solanacearum. PAGE isoenzymatic analysis showed that there were one new POD band and two new SOD bands elicited, and at least two isoformic POD bands and two SOD bands were observably intensified compared to the corresponding control. Conclusion: Our results suggest that not only defense-related enzymatic activitieswere elevated but also the new isoenzymatic isoforms were induced in patchouli inoculated with R. solanacearum