Modulation of Induced Cytotoxicity of Doxorubicin by Using Apoferritin and Liposomal Cages

Doxorubicin is an effective chemotherapeutic drug, however, its toxicity is a significant limitation in therapy. Encapsulation of doxorubicin inside liposomes or ferritin cages decreases cardiotoxicity while maintaining anticancer potency. We synthesized novel apoferritin- and liposome-encapsulated forms of doxorubicin (“Apodox” and “lip-8-dox”) and compared its toxicity with doxorubicin and Myocet on prostate cell lines. Three different prostatic cell lines PNT1A, 22Rv1, and LNCaP were chosen. The toxicity of the modified doxorubicin forms was compared to conventional doxorubicin using the MTT assay, real-time cell impedance-based cell growth method (RTCA), and flow cytometry. The efficiency of doxorubicin entrapment was 56% in apoferritin cages and 42% in the liposome carrier. The accuracy of the RTCA system was verified by flow-cytometric analysis of cell viability. The doxorubicin half maximal inhibition concentrations (IC₅₀) were determined as 170.5, 234.0, and 169.0 nM for PNT1A, 22Rv1, and LNCaP, respectively by RTCA. Lip8-dox is less toxic on the non-tumor cell line PNT1A compared to doxorubicin, while still maintaining the toxicity to tumorous cell lines similar to doxorubicin or epirubicin (IC₅₀ = 2076.7 nM for PNT1A vs. 935.3 and 729.0 nM for 22Rv1 and LNCaP). Apodox IC₅₀ was determined as follows: 603.1, 1344.2, and 931.2 nM for PNT1A, 22Rv1, and LNCaP.     

Light Quality and Intensity Modulate Cold Acclimation in Arabidopsis

Plant survival in temperate zones requires efficient cold acclimation, which is strongly affected by light and temperature signal crosstalk, which converge in modulation of hormonal responses. Cold under low light conditions affected Arabidopsis responses predominantly in apices, possibly because energy supplies were too limited for requirements of these meristematic tissues, despite a relatively high steady-state quantum yield. Comparing cold responses at optimal light intensity and low light, we found activation of similar defence mechanisms—apart from CBF1–3 and CRF3–4 pathways, also transient stimulation of cytokinin type-A response regulators, accompanied by fast transient increase of trans-zeatin in roots. Upregulated expression of components of strigolactone (and karrikin) signalling pathway indicated involvement of these phytohormones in cold responses. Impaired response of phyA, phyB, cry1 and cry2 mutants reflected participation of these photoreceptors in acquiring freezing tolerance (especially cryptochrome CRY1 at optimal light intensity and phytochrome PHYA at low light). Efficient cold acclimation at optimal light was associated with upregulation of trans-zeatin in leaves and roots, while at low light, cytokinin (except cis-zeatin) content remained diminished. Cold stresses induced elevation of jasmonic acid and salicylic acid (in roots). Low light at optimal conditions resulted in strong suppression of cytokinins, jasmonic and salicylic acid.     

Active Light-Powered Antibiofilm ZnO Micromotors with Chemically Programmable Properties

Bacterial biofilms are multicellular communities firmly attached to solid extracellular substrates. They are considered the primary cause of huge economic losses, from medicine due to medical implants’ failure to large infrastructure due to enhanced pipe corrosion. Therefore, their eradication is highly desirable. Here, the preparation of ZnO self-propelled micromotors is reported, programming their morphology and motion properties through Ag doping. The ZnO:Ag micromotors actively move upon light irradiation via a self-electrophoretic mechanism, showing excellent light-controlled on/off switching motion. At the same time, the rapid and effective removal of both gram-positive and gram-negative bacteria biofilms from the solid surface is demonstrated, exploiting the well-known antibacterial activity of both Ag and ZnO as well as the enhanced diffusion of the micromotors. The new concept for the low-cost and scalable preparation of chemically programmable Ag-doped ZnO micromotors here illustrated opens a new route toward the formulation of a new class of light-driven semiconducting self-propelled micromotors for environmental applications.     

Assessment of Microbially Influenced Corrosion Risk in Slovak Pipeline Transmission Network

Microbial activities are particularly serious in buried natural gas pipelines resulting in high corrosion costs. It is a mater of necessity to deal with this factor during the evaluation of corrosion risk. The objective of this investigation was to determine to what extent the main factors of environment are responsible for biocorrosion behavior in particular transmission pipeline sections running through Slovakia and subsequently evaluate the biocorrosion risk in the studied areas. According to the point method the probability and outcome value of three chosen factors, such as soil characteristics, water presence, and location were determined for each excavation. Two from the monitored excavations in the east of Slovakia and three situated in the south of Slovakia were found to be the most hazardous sites in terms of biocorrosion risk.     

Extracellular glutamate increases in the lateral hypothalamus during meal initiation and GABA peaks during satiation: Microdialysis measurement every 30 s.

Glutamate injected into the lateral hypothalamus can initiate eating, and gamma-aminobutyric acid (GABA) can stop it. This leads to the hypothesis that glutamate inputs are active at the beginning of a meal, and GABA is released at the end. To test this theory, the authors used microdialysis to sample glutamate and GABA simultaneously before, during, and after a meal. Food-deprived rats ate a meal of chow. Glutamate increased during the first third of the meal, then decreased to below baseline while the rats were still eating. GABA also increased at the start of the meal but continued rising and peaked during the last third of the meal. Glutamate may drive a hypothalamic system for eating, and GABA may oppose it. (PsycINFO Database Record (c) 2010 APA, all rights reserved)