Multicellular Tumor Spheroids (MCTS) as a 3D In Vitro Evaluation Tool of Nanoparticles

Multicellular tumor spheroid models (MCTS) are often coined as 3D in vitro models that can mimic the microenvironment of tissues. MCTS have gained increasing interest in the nano‐biotechnology field as they can provide easily accessible information on the performance of nanoparticles without using animal models. Considering that many countries have put restrictions on animals testing, which will only tighten in the future as seen by the recent developments in the Netherlands, 3D models will become an even more valuable tool. Here, an overview on MCTS is provided, focusing on their use in cancer research as most nanoparticles are tested in MCTS for treatment of primary tumors. Thereafter, various types of nanoparticles—from self‐assembled block copolymers to inorganic nanoparticles, are discussed. A range of physicochemical parameters including the size, shape, surface chemistry, ligands attachment, stability, and stiffness are found to influence nanoparticles in MCTS. Some of these studies are complemented by animal studies confirming that lessons from MCTS can in part predict the behaviour in vivo. In summary, MCTS are suitable models to gain additional information on nanoparticles. While not being able to replace in vivo studies, they can bridge the gap between traditional 2D in vitro studies and in vivo models.     

The influence of user expertise and phone complexity on performance, ease of use and learnability of different mobile phones

The study focuses on usability, ease of use and learnability of three different mobile phones (Nokia 3210, Siemens C35i, Motorola P7389). The first independent variable refers to the complexity of the menu (depth/breadth of the menu tree) and navigation keys (number/functionality). The Nokia phone had the lowest and the Motorola the highest complexity, with the Siemens phone ranging between them. The second independent variable was user expertise: 30 novices and 30 experts solved six telephone tasks. In order to assess effects of learnability, tasks were presented twice. Differences between the mobile phones regarding effectiveness, efficiency and learnability were found: The best performance was shown by Nokia users. The remaining two phones did not differ significantly, although the most complex phone was superior to the phone of medium complexity which had the lowest performance. Moreover, an effect of expertise was confirmed, though suboptimal interfaces were identified as lessening the advantage of expertise. Specific weaknesses of the tested phones are discussed.     

Creativity in Japanese Society

‘The Japanese are not creative, they just copy….’ This prejudice often crops up when you ask Western people about the creativity of the Japanese. However, Japanese industry is at the leading edge in many industrial sectors and one cannot adhere to this prejudice any longer. Japanese creativity is interesting from two points of view. First, Japanese industry is very competitive and the success cannot be explained by a single factor, like low wages or production costs. Secondly, there is a big difference between Japanese and western civilization and a comparison shows cultural influences on creativity in understanding and practice. However, the cultural specialities which are labelled as Japanese are mostly characteristic of other East Asian cultures as well.     

Comparison between normal and reverse thin crystalline silicon solar cells

The newly developed ingot growing techniques, as the three-grain and the columnar multigrain ingot processes, are now offering the possibility of slicing thinner wafers (≤ 100 μm). In this paper we present the results obtained on p type large area (≥ 100 cm²) and 100 μm thick wafers by using both conventional and reverse cell manufacturing technologies.The conventional cells are provided with aluminium or boron BSF plus screen-printed silver mirror or a silver-aluminium net; the reverse cells have a FSF and the deep back junction completely covered by a screen-printed or CVD silver layer.The constructing parameters have been chosen on the base of one and two dimensions modeling and both raw material and devices have been completely characterized.This work shows that very thin wafers do not introduce serious problems for the conventional manufacturing of solar cells. The efficiencies of the normal and of the reverse cells are found to be comparable and are of the same order than those of thicker cells, however at a significant lower cost. The main obtained result has to be related to the demonstration of a cell manufacturing feasibility starting from very thin wafers.     

Quantitative measurement of gas hold-up distribution in a stirred chemical reactor using X-ray cone-beam computed tomography

Cone-beam type X-ray computed tomography (CBCT) is a potential method to measure three-dimensional phase distributions in vessels. An example for that is the measurement of gas profiles in stirred chemical reactors. Such data are highly valuable for the assessment and evaluation of chemical processes, for optimisation of the reactor and stirrer design, and for evaluation of computational fluid dynamics codes used to model the fluid flow and heat transfer in reactive systems. However, there are considerable difficulties for accurate quantitative measurements due to beam hardening and radiation scattering effects. In a theoretical and experimental work we have investigated the non-linear effects of both physical phenomena and developed a suitable measurement setup as well as calibration and software correction methods to achieve a highly accurate measurement of void fraction profiles with CBCT.     

Sensitivity to Cisplatin in Head and Neck Cancer Cells Is Significantly Affected by Patient-Derived Cancer-Associated Fibroblasts

Cancer-associated fibroblasts (CAFs) are one of the most abundant and critical components of the tumor stroma. CAFs can impact many important steps of cancerogenesis and may also influence treatment resistance. Some of these effects need the direct contact of CAFs and cancer cells, while some involve paracrine signals. In this study, we investigated the ability of head and neck squamous cell carcinomas (HNSCC) patient-derived CAFs to promote or inhibit the colony-forming ability of HNSCC cells. The effect of cisplatin on this promoting or inhibiting influence was also studied. The subsequent analysis focused on changes in the expression of genes associated with cancer progression. We found that cisplatin response in model HNSCC cancer cells was modified by coculture with CAFs, was CAF-specific, and different patient-derived CAFs had a different “sensitizing ratio”. Increased expression of VEGFA, PGE2S, COX2, EGFR, and NANOG in cancer cells was characteristic for the increase of resistance. On the other hand, CCL2 expression was associated with sensitizing effect. Significantly higher amounts of cisplatin were found in CAFs derived from patients who subsequently experienced a recurrence. In conclusion, our results showed that CAFs could promote and/or inhibit colony-forming capability and cisplatin resistance in HNSCC cells via paracrine effects and subsequent changes in gene expression of cancer-associated genes in cancer cells.     

Extracellular Vesicles Tune the Immune System in Renal Disease: A Focus on Systemic Lupus Erythematosus,Antiphospholipid Syndrome,Thrombotic Microangiopathy and ANCA-Vasculitis

Extracellular vesicles (EV) are microparticles released in biological fluids by different cell types, both in physiological and pathological conditions. Owing to their ability to carry and transfer biomolecules, EV are mediators of cell-to-cell communication and are involved in the pathogenesis of several diseases. The ability of EV to modulate the immune system, the coagulation cascade, the angiogenetic process, and to drive endothelial dysfunction plays a crucial role in the pathophysiology of both autoimmune and renal diseases. Recent studies have demonstrated the involvement of EV in the control of renal homeostasis by acting as intercellular signaling molecules, mediators of inflammation and tissue regeneration. Moreover, circulating EV and urinary EV secreted by renal cells have been investigated as potential early biomarkers of renal injury. In the present review, we discuss the recent findings on the involvement of EV in autoimmunity and in renal intercellular communication. We focused on EV-mediated interaction between the immune system and the kidney in autoimmune diseases displaying common renal damage, such as antiphospholipid syndrome, systemic lupus erythematosus, thrombotic microangiopathy, and vasculitis. Although further studies are needed to extend our knowledge on EV in renal pathology, a deeper investigation of the impact of EV in kidney autoimmune diseases may also provide insight into renal biological processes. Furthermore, EV may represent promising biomarkers of renal diseases with potential future applications as diagnostic and therapeutic tools.     

Solvent and oxygen effects on the free radical polymerization of 6-O-vinyladipoyl-d-glucopyranose

The vinyl ester-type glycomonomer 6-O-vinyladipoyl-d-glucopyranose was polymerized in water and alcohol solutions. In all cases, long polymerization times were necessary to achieve reasonable conversions. Depending on the nature of the solvent, polydisperse glycopolymers were obtained possessing a molecular weight ranging between 10,000 and 122,000 Da (PS equivalent). Higher alcohols appeared to act as chain transfer agents and oligomers with DP_n between 2 and 6 were indeed obtained when 2-propanol was the solvent. Also, thorough oxygen removal from the reaction mixture proved to be essential for the success of the experiment, plain nitrogen sparging being ineffective in most cases.