The Induction of Apoptosis by SV40 T Antigen Correlates with c-junOverexpression

AbstractSimian virus (SV40) T antigen shares many characteristics with adenovirus E1A which is known to induce apoptosis. To verify the potential of SV40 T antigen-mediated apoptosis, we stably expressed T antigen in immortalized human epithelial cells (Z172 and HaCaT). We found that SV40 T antigen could directly cause apoptosis in 22–27% of these cells under normal growth condition as measured by chromatin condensation and nucleosomal fragmentation. The apoptosis of HaCaT cells which contain mutant p53 suggests the p53-independent nature of T antigen-mediated apoptosis. T antigen-induced apoptosis was associated with increased expression of c-Jun protein. Moreover, the overexpression of c-junalone in these cells also induced apoptosis, indicating that c-junmight play an important role in T antigen-induced apoptosis

Estimation of cell concentration using high-frequency ultrasonic backscattering

Abstract Cell concentration is a crucial quantity for both clinical diagnostic examinations and cell culture studies. However, typical modalities for cell concentration measurements are either time-consuming or not cost-effective. In the present study, cell concentration is estimated using high-frequency ultrasonic backscattering. Validation tests indicate that the proposed method can differentiate red blood cells (RBCs) of various hematocrits. A 50-MHz ultrasound system with appropriate sensitivity is utilized to estimate cell concentrations from a small volume of RBCs suspended in saline, with hematocrits ranging from 1.66 × 10 -4 to 10%, and fibroblasts, with concentrations ranging from 2 × 10 4 to 128 × 10 4 cells/mL. The backscatter strength and statistical distribution, characterized by the Nakagami parameter, are calculated from gated signals for quantitatively assessing the samples. Results show that the backscatter strength of RBCs linearly increases with increasing hematocrit level in the hematocrit range of 3 to 10%, which agrees well with results of previous studies. The backscatter strength of RBCS has an exponential relationship with the hematocrit level in the hematocrit range of 1.66 × 10 -4 to 3%. The corresponding Nakagami parameter is sensitive to electronic noise as long as the signal-to-noise ratio decreasing follows with the decrease of RBC hematocrits at the concentration lower than 0.85%. The backscatter strength of fibroblasts exponentially increases with increasing fibroblasts concentration, which is consistent with results obtained from typical optical density measurements. A linear relationship, with correlation coefficient of 0.99, between the results of ultrasonic backscattering and those of the optical density measurements is established. High-frequency ultrasonic backscattering can be applied to sensitively estimate the concentrations of small volumes of cells

Nuclear Receptor Interaction Protein (NRIP) expression assay using human tissue microarray and immunohistochemistry technology confirming nuclear localization

Background: A novel human nuclear receptor interaction protein (NRIP) has recently been discovered by Chen SL et al , which may play a role in enhancing the transcriptional activity of steroid nuclear receptors in prostate (LNCaP) and cervical (C33A) cancer cell lines. However, knowledge about the biological functions and clinical implications of NRIP, is still incomplete. Our aim was to determine the distribution of NRIP expression and to delineate the cell types that express NRIP in various malignant tumors and healthy non-pathological tissues. This information will significantly affect the exploration of its physiological roles in healthy and tumor cells. Methods: By using tissue microarray (TMA) technology and an anti-NRIP monoclonal antibody immunohistochemical (IHC) survey, NRIP expression was examined in 48 types of tumors and in a control group of 48 matched or unmatched healthy non-neoplastic tissues. Results: Our survey results showed that ten cases were revealed to express the NRIP in six malignancies (esophageal , colon, breast, ovarian, skin, and pancreatic cancers), but not all of these specific tumor types consistently showed positive NRIP expression. Moreover, malignant tumors of the stomach, prostate, liver, lung, kidney, uterine cervix, urinary bladder, lymph node, testis, and tongue revealed no NRIP expression. Among the control group of 48 matched and unmatched nonneoplastic tissues, all of them demonstrated IHC scores less than the cut-off threshold of 3. In addition , ten cores out of thirty-six carcinomatous tissues revealed positive NRIP expression, which indicated that NRIP expression increases significantly in carcinoma tissue cores , comparing to the matched controlled healthy tissues. Conclusion: This is the first study to use a human TMA and IHC to validate the nuclear localization for this newly identified NRIP expression. In considering the use of NRIP as a potential diagnostic tool for human malignancies survey , it is important to note that NRIP expression carries a sensitivity of only 23%, but has a specificity of 100%. There is also a significant difference in positive NRIP expression between primary carcinomatous tissues and matched controlled healthy tissues. Although further large-scale studies will merit to be conducted to evaluate its role as a potential adjunct for cancer diagnosis, data from this study provides valuable references for the future investigation of the biological functions of NRIP in humans

Granulation and microbial community dynamics in the chitosan-supplemented anaerobic treatment of wastewater polluted with organic solvents

The effect of chitosan on the development of granular sludge in upflow anaerobic sludge blanket reactors (UASB) when treating wastewater polluted with the organic solvents ethanol, ethyl acetate, and 1-ethoxy-2-propanol was evaluated. Three UASB reactors were operated for 219 days at ambient temperature with an organic loading rate (OLR) of between 0.3 kg COD m−3 d−1 and 20 kg COD m−3 d−1. One reactor was operated without the addition of chitosan, while the other two were operated with the addition of chitosan doses of 2.4 mg gVSS−1 two times. The three reactors were all able to treat the OLR tested with COD removal efficiencies greater than 90%. However, the time required to reach stable operation was considerably reduced in the chitosan-assisted reactors. The development of granules in the reactors with chitosan was accelerated and granules larger than 2000 μm were only observed in these reactors. In addition, these granules exhibited better physicochemical characteristics: the mean particle diameter (540 and 613 μm) was approximately two times greater than in the control reactor (300 μm), and the settling velocities exceeded 35 m h−1. The extracellular polymeric substances (EPS) in the reactors with the chitosan was found to be higher than in the control reactor. The protein-EPS content has been correlated with the granule size. The analyses of the microbial communities, performed through denaturing gradient gel electrophoresis and high-throughput sequencing, revealed that the syntrophic microorganisms belonging to genus Geobacter and the hydrogenotrophic methanogen Methanocorpusculum labreanum were predominant in the granules. Other methanogens like Methanosaeta species were found earlier in the chitosan-assisted reactors than in the control reactor

Inhibition of cell motility by troglitazone in human ovarian carcinoma cell line

<p>Abstract</p> <p>Background</p> <p>Troglitazone (TGZ) is a potential anticancer agent. Little is known about the effect of this agent on cancer cell migration.</p> <p>Methods</p> <p>Human ovarian carcinoma cell line, ES-2 cells were treated with various concentrations of TGZ. Cell migration was evaluated by wound-healing and Boyden chamber transwell experiments. PPARγ expression was blocked by PPARγ small interfering RNA. The effects of TGZ on phosphorylation of FAK, PTEN, Akt were assessed by immunoblotting using phospho-specific antibodies. The cellular distribution of paxillin, vinculin, stress fiber and PTEN was assessed by immunocytochemistry.</p> <p>Results</p> <p>TGZ dose- and time-dependently impaired cell migration through a PPARγ independent manner. TGZ treatment impaired cell spreading, stress fiber formation, tyrosine phosphorylation of focal adhesion kinase (FAK), and focal adhesion assembly in cells grown on fibronectin substratum. TGZ also dose- and time-dependently suppressed FAK autophosphorylation and phosphorylation of the C-terminal of PTEN (a phosphatase). At concentration higher than 10 μM, TGZ caused accumulation of PTEN in plasma membrane, a sign of PTEN activation.</p> <p>Conclusion</p> <p>These results indicate that TGZ can suppress cultured ES-2 cells migration. Our data suggest that the anti-migration potential of TGZ involves in regulations of FAK and PTEN activity.</p