65 research outputs found
Microarray profiling reveals the integrated stress response is activated by halofuginone in mammary epithelial cells
<p>Abstract</p> <p>Background</p> <p>The small molecule Halofuginone (HF) is a potent regulator of extracellular matrix (ECM ) gene expression and is unique in its therapeutic potential. While the basis for HF effects is unknown, inhibition of TGFβ signaling and activation of the amino acid restriction response (AAR) have been linked to HF transcriptional control of a number of ECM components and amelioration of fibrosis and alleviation of autoimmune disease by regulation of Th17 cell differentiation, respectively. The aim of this study was to generate a global expression profile of HF targets in epithelial cells to identify potential mediators of HF function in this cell type.</p> <p>Results</p> <p>We report that HF modulation of the expression of the ECM remodeling protein Mmp13 in epithelial cells is separable from previously reported effects of HF on TGFβ signal inhibition, and use microarray expression analysis to correlate this with transcriptional responses characteristic of the Integrated Stress Response (ISR).</p> <p>Conclusions</p> <p>Our findings suggest activation of the ISR may be a common mechanism underlying HF biological effects.</p
Stat3 Activates the Receptor Tyrosine Kinase Like Orphan Receptor-1 Gene in Chronic Lymphocytic Leukemia Cells
BACKGROUND: The receptor tyrosine kinase like orphan receptor (ROR)-1 gene is overexpressed in chronic lymphocytic leukemia (CLL). Because Stat3 is constitutively activated in CLL and sequence analysis revealed that the ROR1 promoter harbors gamma-interferon activation sequence-like elements typically activated by Stat3, we hypothesized that Stat3 activates ROR1. METHODOLOGY/PRINCIPAL FINDINGS: Because IL-6 induced Stat3 phosphorylation and upregulated Ror1 protein levels in MM1 cells, we used these cells as a model. We transfected MM1 cells with truncated ROR1 promoter luciferase reporter constructs and found that IL-6 induced luciferase activity of ROR1-195 and upstream constructs. Co-transfection with Stat3 siRNA reduced the IL-6-induced luciferase activity, suggesting that IL-6 induced luciferase activity by activating Stat3. EMSA and the ChIP assay confirmed that Stat3 binds ROR1, and EMSA studies identified two Stat3 binding sites. In CLL cells, EMSA and ChIP studies determined that phosphorylated Stat3 bound to the ROR1 promoter at those two ROR1 promoter sites, and ChIP analysis showed that Stat3 co-immunoprecipitated DNA of STAT3, ROR1, and several Stat3-regulated genes. Finally, like STAT3-siRNA in MM1 cells, STAT3-shRNA downregulated STAT3, ROR1, and STAT3-regulated genes and Stat3 and Ror1 protein levels in CLL cells. CONCLUSION/SIGNIFICANCE: Our data suggest that constitutively activated Stat3 binds to the ROR1 promoter and activates ROR1 in CLL cells
The HELLP syndrome: Clinical issues and management. A Review
<p>Abstract</p> <p>Background</p> <p>The HELLP syndrome is a serious complication in pregnancy characterized by haemolysis, elevated liver enzymes and low platelet count occurring in 0.5 to 0.9% of all pregnancies and in 10–20% of cases with severe preeclampsia. The present review highlights occurrence, diagnosis, complications, surveillance, corticosteroid treatment, mode of delivery and risk of recurrence.</p> <p>Methods</p> <p>Clinical reports and reviews published between 2000 and 2008 were screened using Pub Med and Cochrane databases.</p> <p>Results and conclusion</p> <p>About 70% of the cases develop before delivery, the majority between the 27th and 37th gestational weeks; the remainder within 48 hours after delivery. The HELLP syndrome may be complete or incomplete. In the Tennessee Classification System diagnostic criteria for HELLP are haemolysis with increased LDH (> 600 U/L), AST (≥ 70 U/L), and platelets < 100·10<sup>9</sup>/L. The Mississippi Triple-class HELLP System further classifies the disorder by the nadir platelet counts. The syndrome is a progressive condition and serious complications are frequent. Conservative treatment (≥ 48 hours) is controversial but may be considered in selected cases < 34 weeks' gestation. Delivery is indicated if the HELLP syndrome occurs after the 34th gestational week or the foetal and/or maternal conditions deteriorate. Vaginal delivery is preferable. If the cervix is unfavourable, it is reasonable to induce cervical ripening and then labour. In gestational ages between 24 and 34 weeks most authors prefer a single course of corticosteroid therapy for foetal lung maturation, either 2 doses of 12 mg betamethasone 24 hours apart or 6 mg or dexamethasone 12 hours apart before delivery. Standard corticosteroid treatment is, however, of uncertain clinical value in the maternal HELLP syndrome. High-dose treatment and repeated doses should be avoided for fear of long-term adverse effects on the foetal brain. Before 34 weeks' gestation, delivery should be performed if the maternal condition worsens or signs of intrauterine foetal distress occur. Blood pressure should be kept below 155/105 mmHg. Close surveillance of the mother should be continued for at least 48 hours after delivery.</p
Balance and concentration of nitrogen and potassium affect growth and nutrient status in soilless cultivated lisianthus
Purpose: Nitrogen (N) / potassium (K) nutrient balance has been studied for some ornamental plants, however, available information is limited. Here we investigate the optimum N and K balance and concentration for lisianthus production in soilless medium. Materials and methods: The effect of three N / K balances: 1.43, 2.14 and 4.29, prepared by varying the concentration of N and K, were evaluated in lisianthus grown in soilless medium (volcanic rock). Results: Plants fertigated with a N / K balance of 2.14 exhibited enhanced height and stem dry weight when compared to plants fertigated with a balance of 4.29, and a higher flower buds count and total dry weight than those fertigated with a balance of 1.43 or 4.29. Plants fertigated with a balance of 2.14 exhibited increased dry weight when N was reduced from 15 to 9 meq L−1 and K from 7 to 4.2 meq L−1, suggesting that lisianthus does not require high levels of these nutrients. Although shoot N concentration was not correlated with N concentration in the nutrient solution or balance, increasing N in the shoot was associated with higher P and Mg in the plant tissues. In general, P, Ca, and Mg in plant tissues were unaffected by the external N / K balance, however, the internal P and Mg concentrations were positively correlated with shoot dry weight. Shoot K concentration significantly increased when the N / K balance decreased, which is related to the higher concentrations of external K when the balance decreased. Conclusions: The optimum N / K balance for lisianthus was 2.14. However, there was a concentration effect, as fertigation with solutions containing a N / K balance of 2.14 and an N and K concentration of 9 and 4.2 meq L−1 respectively, resulted in plants with the greatest dry weight
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