Media replenishment: A tool for the analysis of high-cell density perfusion systems

A simple method to analyze media consumption and by-product build-up in high-cell-density perfusion cultures has been developed. This technique makes use of media replenishment strategy which can be used to decouple the two phenomena. Also, the replenished media method can be used to identify limitation by complex and undefined media components such as bovine serum.     

Phosphate and phosphite have a differential impact on the proteome and phosphoproteome of Arabidopsis suspension cell cultures

Phosphorus absorbed in the form of phosphate (H₂PO₄⁻) is an essential but limiting macronutrient for plant growth and agricultural productivity. A comprehensive understanding of how plants respond to phosphate starvation is essential for the development of more phosphate-efficient crops. Here we employed label-free proteomics and phosphoproteomics to quantify protein-level responses to 48 h of phosphate versus phosphite (H₂PO₃⁻) resupply to phosphate-deprived Arabidopsis thaliana suspension cells. Phosphite is similarly sensed, taken up and transported by plant cells as phosphate, but cannot be metabolized or used as a nutrient. Phosphite is thus a useful tool for differentiating between non-specific processes related to phosphate sensing and transport and specific responses to phosphorus nutrition. We found that responses to phosphate versus phosphite resupply occurred mainly at the level of protein phosphorylation, complemented by limited changes in protein abundance, primarily in protein translation, phosphate transport and scavenging, and central metabolism proteins. Altered phosphorylation of proteins involved in core processes such as translation, RNA splicing and kinase signaling was especially important. We also found differential phosphorylation in response to phosphate and phosphite in 69 proteins, including splicing factors, translation factors, the PHT1;4 phosphate transporter and the HAT1 histone acetyltransferase – potential phospho-switches signaling changes in phosphorus nutrition. Our study illuminates several new aspects of the phosphate starvation response and identifies important targets for further investigation and potential crop improvement.     

Maternal Urinary Iodine Concentration and Pregnancy Outcomes: Tehran Thyroid and Pregnancy Study

Biological Trace Element Research - Long-term use of hair dyes has potential effects on metal content in hair. However, little research dissects the specific distribution and composition variations...     

The Antimicrobial Peptide,Nisin, Synergistically Enhances the Cytotoxic and Apoptotic Effects of Rituximab Treatment on Human Burkitt’s Lymphoma Cell Lines

Background:Non-Hodgkin''s lymphomas comprise the most common hematological cancers worldwide and consist of a heterogenous group of malignancies affecting the lymphoid system. Treatment of non-Hodgkin’s lymphoma has been significantly enhanced with the addition of Rituximab to the standard chemotherapy regimen. However, even with the advancement of treatment patients continue to relapse and develop resistance to Rituximab, rendering subsequent treatments unsuccessful. The use of novel drugs with unique antitumor mechanisms has gained considerable attention. In this study, we explored the in vitro anti-cancer effects of the combined therapy of Rituximab and Nisin on human Burkitt’s lymphoma cells.Methods:The human Burkitt’s lymphoma cells lines, Raji and Daudi, were treated with Nisin, Rituximab, or a combination of the two agents at various concentrations. Cytotoxicity following treatment was determined using cell viability assay. The degree of apoptosis was verified via flow cytometric analysis using FITC annexin V/PI staining.Results:Our findings show that the combined treatment of Rituximab and Nisin results in a more significant reduction in the survival of Raji and Daudi Burkitt’s lymphoma cells, compared to Nisin or Rituximab treatment alone. Additionally, our results indicate that Nisin can induce a significant degree of apoptosis in the Burkitt’s lymphoma cells compared to the negative controls. However, the addition of Nisin to the Rituximab treatment synergistically enhances the apoptotic antitumor effect.Conclusion:This study demonstrates the synergistic antitumor effect of Nisin treatment in vitro to enhance tumor cell apoptosis and the potential value of Nisin as an adjunct therapy in the treatment of lymphoma.Key Words: Apoptosis, Burkitt’s lymphoma, Cell viability, Combination, Nisin, Rituximab     

Aryltellurium(IV) trichlorides, aryl(trans-2-chloro-1-cycloalkyl)tellurium(IV) dichlorides, and aryl(trans-2-ethoxy-1-cycloalkyl)tellurium(IV) dichlorides

Aryltellurium(IV) trichlorides react with parent arenes to give diaryltellurium(IV) dichlorides and with cycloalkenes to give aryl(trans-2-chloro-1-cycloalkyl)tellurium(IV) dichlorides or aryl(trans-2-ethoxy-1- cycloalkyl)tellurium(IV) dichlorides in the presence of ethanol.