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Introduction: Point-of-care (POC) manufacturing of chimeric antigen receptor (CAR) modified T cell has expanded rapidly over the last decade. In addition to the use of CD19 CAR T cells for hematological diseases, there is a growing interest in targeting a variety of tumor-associated epitopes. Methods: Here, we report the manufacturing and characterization of autologous anti-CD20 CAR T cells from melanoma patients within phase I clinical trial (NCT03893019). Using a second-generation lentiviral vector for the production of the CD20 CAR T cells on the CliniMACS Prodigy®. Results: We demonstrated consistency in cell composition and functionality of the products manufactured at two different production sites. The T cell purity was >98.5%, a CD4/CD8 ratio between 2.5 and 5.5 and transduction rate between 34% and 61% on day 12 (harvest). Median expansion rate was 53-fold (range, 42-65-fold) with 1.7-3.8×109 CAR T cells at harvest, a sufficient number for the planned dose escalation steps (1×105/kg, 1×106/kg, 1×107/kg BW). Complementary research of some of the products pointed out that the CAR+ cells expressed mainly central memory T-cell phenotype. All tested CAR T cell products were capable to translate into T cell activation upon engagement of CAR target cells, indicated by the increase in pro-inflammatory cytokine release and by the increase in CAR T cell amplification. Notably, there were some interindividual, cell-intrinsic differences at the level of cytokine release and amplification. CAR-mediated T cell activation depended on the level of CAR cognate antigen. Discussion: In conclusion, the CliniMACS Prodigy® platform is well suited for decentralized POC manufacturing of anti-CD20 CAR T cells and may be likewise applicable for the rapid and automated manufacturing of CAR T cells directed against other targets. [ABSTRACT FROM AUTHOR]

The aim of the current study is to investigate student biology teachers' cognitive structures related to "diffusion" through the free word-association test and the drawing-writing technique. As the research design of the study, the qualitative research method was applied. The data were collected from 44 student biology teachers. The free word-association test and the drawing-writing technique were used as data collection instruments. The data were subject to content analysis and divided into categories through coding. In the analysis, the categories were formed and determined through the results of word-association test and drawing-writing test which were completed by the student biology teachers. With the help of these categories, the cognitive structures of student biology teachers were explained. The data collected through the study were divided into 8 categories ("defining diffusion," "diffusion environments," "diffusion-forms of substance transfer," "places and structures where diffusion occurs," "substances in diffusion and their characteristics," "importance of diffusion in plants," "examples of diffusion" and "factors influencing diffusion speed"). The common and dominant category in both assessment instruments is "defining diffusion". On the other hand, it was determined that student biology teachers had alternative concepts related to diffusion. At the end of the article, comprehensive suggestions are presented on the subject.

The purpose of the current study is to determine biology student teachers' cognitive structures on the concept of microscope. Qualitative research methodology has been applied in the study. The data were collected from biology student teachers. Free word association test and drawing-writing test were used to collect data. The data collected were subject to content analysis and divided into categories. According to the analyses conducted, while 6 categories were determined through the free word association test in biology student teachers' cognitive structures on the concept of microscope, in the drawing-writing technique, 5 categories were specified. Through both measurement tools, rich data were obtained, supporting, expanding on, and explaining one another. In this context, it was determined through both measurement tools that student teachers' cognitive structures focused on "microscope tools". Moreover, the data collected through these data collection instruments indicated that student teachers had alternative conceptions about the concept of microscope. Alternative conceptions were determined in almost all categories, which may be attributed to the fact that student teachers have naive experiences and/or the units that require the use of microscopes during the laboratory work included in biology curriculum which is provided in different teaching levels at university or pre-university education cannot be explored efficiently and appropriately.

The purpose of this study is to determine biology student teachers' cognitive structure with regard to "Blood". Qualitative research method has been used. The free word association test and the draw-write technique have been used in collection of data. The data obtained have been evaluated and divided into categories based on content analysis. According to the analysis results, in biology student teachers' conceptual structures with regard to blood, while nine categories have been determined for the free word association test, eight categories have been determined for the draw-write technique. Rich data supporting, dilating and explaining one another have been obtained through both measuring tools. In this context, it has been determined through two measuring tools that student teachers' cognitive structures are concentrated in the "blood cells" and blood "groups and determination of blood groups" categories. Furthermore, in the data collected through both measuring tools in the determined categories. It has been determined that student teachers have alternative concepts on blood concept.

The numerical investigation of the effects of the oscillatory primary flow field and the resulting steady second order acoustic streaming structures on the development of the thermal convection process in a nitrogen-filled shallow enclosure is discussed. An additional convective heat transfer mode is introduced in to the systems in zero-gravity environment due to acoustic streaming.

Clinical studies using autologous CAR T cells have achieved spectacular remissions in refractory CD19+ B cell leukaemia, however some of the patient treatments with CAR T cells failed. Beside the heterogeneity of leukaemia, the distribution and senescence of the autologous cells from heavily pretreated patients might be further reasons for this. We performed six consecutive large-scale manufacturing processes for CD20 CAR T cells from healthy donor leukapheresis using the automated CliniMACS Prodigy® platform. Starting with a CD4/CD8-positive selection, a high purity of a median of 97% T cells with a median 65-fold cell expansion was achieved. Interestingly, the transduction rate was significantly higher for CD4+ compared to CD8+ T cells and reached in a median of 23%. CD20 CAR T cells showed a good specific IFN-γ secretion after cocultivation with CD20+ target cells which correlated with good cytotoxic activity. Most importantly, 3 out of 5 CAR T cell products showed an increase in telomere length during the manufacturing process, while telomere length remained consistent in one and decreased in another process. In conclusion, this shows for the first time that beside heterogeneity among healthy donors, CAR T cell products also differ regarding cell senescence, even for cells manufactured in a standardised automated process. [ABSTRACT FROM AUTHOR]

Acoustic streaming motion in a compressible gas filled two-dimensional rectangular enclosure is simulated and the effects of the sound field intensity on the formation process of streaming structures are investigated numerically. The oscillatory flow field in the enclosure is created by the vibration of the left wall of the enclosure. The frequency of the wall vibration is chosen such that the lowest acoustic mode propagates along the enclosure. The fully compressible form of the Navier-Stokes equations is considered and an explicit time-marching algorithm is used to track the acoustic waves. The formation of the wave field in the enclosure is computed and fully described and the acoustic boundary layer development is predicted. The interaction of the wave field with viscous effects and the formation of streaming structures are revealed by time-averaging the solutions over a given period. The strength of the pressure waves associated with the acoustic effect and the resulting streaming flow pattern is found to be strongly correlated to the maximum displacement of the wall during a vibration cycle. The wave form determines the shape of the steady streaming structures in the oscillatory flow field. [ABSTRACT FROM AUTHOR]

The generation and propagation of thermoacoustic waves in water are investigated by solving the fully compressible form of the Navier–Stokes equations. A square enclosure filled with water is considered as the computational domain. Thermally induced pressure waves are generated by rapidly heating the left wall. The thermodynamic properties of water are calculated via an accurate equation of state. The effect of the rapidity of the heating process on the production of thermoacoustic waves is studied, using both impulse (sudden) and gradual changes in the left wall temperature. The thermoacoustic waves are significantly stronger for impulse heating and are found to eventually damp out with time due to viscous losses. Gradual change of the left wall temperature reduced the strength of the pressure wave peaks. [ABSTRACT FROM AUTHOR]

Effects of thermoacoustic wave motion on the developing natural convection process in a compressible gas-filled square enclosure were investigated numerically. In the cases considered, the left wall temperature is raised rapidly (impulsively or gradually) while the right wall is held at a specified temperature. The top and the bottom walls of the enclosure considered are thermally insulated. The numerical solutions of the full Navier–Stokes equations were obtained by employing a highly accurate flux-corrected transport algorithm for the convection terms and by a central differencing scheme for the viscous and diffusive terms. The strength of the pressure waves associated with the thermoacoustic effect and resulting flow patterns are found to be strongly correlated to the rapidity of the wall heating process. Fluid thermal diffusivity was found to affect the strength of the thermoacoustic waves and the resulting interaction with the buoyancy-induced flow. [Copyright &y& Elsevier]

The influence of hydrodynamically developing nonzero mean acoustic streaming motion on transient convective heat transfer in an air-filled rectangular enclosure is studied numerically. The enclosure is two-dimensional with sinusoidal bottom wall spatial temperature distribution. The oscillatory flow under relatively large Womersley number regime conditions is actuated by the periodic vibrations of the enclosure side wall. The side walls of the enclosure are adiabatic, while the top wall is isothermal. The compressible form of the Navier--Stokes equations is considered to predict the oscillatory- and time-averaged mean flow fields. A control-volume method based explicit computational scheme is used to simulate the convective transport in the enclosure. The longitudinal and the transverse temperature gradients strongly affect the flow structure in the enclosure. The mean fluid motion alters the heat transfer behavior compared to the pure conduction. [ABSTRACT FROM AUTHOR]

The DcuS-DcuR system of Escherichia coli is a two-component sensor-regulator that controls gene expression in response to external C4-dicarboxylates and citrate. The DcuS protein is particularly interesting since it contains two PAS domains, namely a periplasmic C4-dicarboxylate-sensing PAS domain (PASp) and a cytosolic PAS domain (PASc) of uncertain function. For a study of the role of the PASc domain, three different fragments of DcuS were overproduced and examined: they were PASc-kinase, PASc, and kinase. The two kinase-domain. containing fragments were autophosphorylated by [γ-32P]ATP. The rate was not affected by fumarate or succinate, supporting the role of the PASp domain in C4-dicarboxylate sensing. Both of the phosphorylated DcuS constructs were able to rapidly pass their phosphoryl groups to DcuR, and after phosphorylation, DcuR dephosphorylated rapidly. No prosthetic group or significant quantity of metal was found associated with either of the PASc-containing proteins. The DNA-binding specificity of DcuR was studied by use of the pure protein. It was found to be converted from a monomer to a dimer upon acetylphosphate treatment, and native polyacrylamide gel electrophoresis suggested that it can oligomerize. DcuR specifically bound to the promoters of the three known DcuSR-regulated genes (dctA, dcuB, and frdA), with apparent KDs of 6 to 32 µM for untreated DcuR and ≤1 to 2 µM for the acetylphosphate-treated form. The binding sites were located by DNase I footprinting, allowing a putative DcuR-binding motif [tandemly repeated (T/A)(A/T)(T/C)(A/T)AA sequences] to be identified. The DcuR-binding sites of the dcuB, dctA, and frdA genes were located 27, 94, and 86 bp, respectively, upstream of the corresponding +I sites, and a new promoter was identified for dcuB that responds to DcuR. [ABSTRACT FROM AUTHOR]