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Glycerol is a widely used signaling bioanalyte in biotechnology. Glycerol can serve as a substrate or product of many metabolic processes in cells. Therefore, quantification of glycerol in fermentation samples with inexpensive, reliable, and rapid sensing systems is of great importance. In this work, an amperometric assay based on one-step designed electroplated functional Pd layers with controlled design was proposed for a rapid and selective measurement of glycerol in yeast fermentation medium. A novel assay utilizing electroplated Pd-sensing layers allows the quantification of glycerol in yeast fermentation medium in the presence of interfering species with RSD below 3% and recoveries ranged from 99 to 103%. The assay requires minimal sample preparation, viz. adjusting of sample pH to 12. The time taken to complete the electrochemical analysis was 3 min. Remarkably, during investigations, it was revealed that sensitivity and selectivity of glycerol determination on Pd sensors were significantly affected by its adsorption and did not depend on the surface structure of sensing layers. This study is expected to contribute to both fundamental and practical research fields related to a preliminary choice of functional sensing layers for specific biotechnology and life science applications in the future.

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Herein, a rapid electrochemical screening of yeasts (Saccharomyces cerevisiae) in vitro mode depending on their optical density, cultivation time and growth medium used was conducted in 3 min by palladium nanoparticles (Pd-NPs)-modified electrodes. Pd-NPs-modified electrodes operated in cyclic voltammetry mode at low scan rates, i.e. 5-20 mV/s supported a low oxidative process in the yeast extracellular matrix. The electrochemical screening relied on an efficient electrooxidation of secondary metabolites, i.e. organohydrazines formed in the extracellular medium as a result of microbial activity of yeast cells. More importantly, during the study the impact of fundamental parameters, viz. type of the matrix and pH on electroanalytical response of Pd-NPs-based electrodes in real fermentation medium was investigated in detail. The efficiency of the proposed in vitro electrochemical screening of yeast extracellular matrix was not affected by pH of the samples or composition of the multicomponent medium, but more likely exclusively depended on the presence of organohydrazines. The potential of this electroanalytical approach towards profiling of the extracellular matrix of Saccharomyces cerevisiae was compared with results obtained by gas chromatography mass-spectrometry (GC-MS) and genetically encoded biosensor (ro-GFP2) assays.

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This study describes the development of a one-pot electrochemical miniaturized system for simultaneous cultivation and monitoring of the oxidative status of living cells. This system consisted of screen-printed electrodes modified by electroplated Pd-NPs as an electrocatalyst (i) and living yeast cells (Saccharomyces cerevisiae) (ii) immobilized on the cytocompatible alginate layer (iii). Briefly, during the course of electrochemical investigations a novel electroactive compound methylhydrazine derivative as a secondary metabolite and result of microbial activity was found in yeast cells and used as a signaling molecule for their biochemical profiling. Under the optimized experimental conditions the signal corresponding to the found electroactive secondary metabolite formed in medium of living cells was measured without sample collecting, transport, storage or pre-treatment steps (i.e. extraction, pre-concentration, chemical derivatization or labeling). The electrochemical dependencies, which were derived by a miniaturized electroanalytical system, were fully validated in a conventional three-electrode system under inert atmosphere (Ar) and in the presence of oxygen (air, O2). It is believed that the proposed one-pot nanoreactors serving simultaneously as nanofermenters and amperometric detectors for the quantification of secondary metabolites formed in medium of living cells can significantly enhance the understanding of ongoing fermentation processes in the future and our knowledge on the biochemistry of yeasts.

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AIM AND BACKGROUND: To assess the use of hypofractionated (HG-RT) versus normofractionated radiation therapy (NF-RT) in Breast Cancer in German speaking countries. MATERIALS AND METHODS: Between July 2017 and August 2017, an email-based survey was sent to all 1408 physicians that are members of the German Society of Radiation Oncology (DEGRO). The survey was completed by 180 physicians including 10 private practice owners and 52 heads of departments. The majority (82.1%) of the participants had >15 years of experience in radiation therapy (RT). RESULTS: The majority (83.9%) of the heads of the departments agreed on using the normofractionated regimen of RT as standard treatment for breast cancer. Several physicians were skeptical about HF-RT with 6.5% of the heads refusing to use HF-RT. 40.3% of the departments had not seen the new German guidelines suggesting HF-RT as the standard treatment for all patients as positive or merely adopted a neutral position toward the guidelines (33.9%). The main points of criticism were increased side effects, an impaired toxicity profile and insufficient data. Most departments (46.8%) that perform HF-RT do so in an individual based manner. CONCLUSIONS: HF-RT remains controversial in German speaking countries. Our data shows that NF-RT remains the predominant method of treatment. HF-RT is only used in a defined group of patients as most German physicians agree that particular patients, especially those at higher risk of RT late effects, may benefit from a less intense, extended fractionation schedule.

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PURPOSE: Lymph node irradiation in breast cancer has gained complexity due to recently published studies and technical innovations which then led to changes in international guidelines. We sought to determine real-time variability in lymph node irradiation in clinical practice in German-speaking countries. METHODS: The Department of Radiation Oncology, Technical University of Munich (TUM), developed an online-based questionnaire focusing on the indication, target definition, and treatment technique of lymph node irradiation in patients with breast cancer. The invitation to participate in the survey was sent to members of the German Society of Radiation Oncology (DEGRO) by e­mail. The results of the survey were exported from the online platform into SPSS for a detailed analysis. RESULTS: In total, 100 physicians completed the questionnaire between 05/2019 and 06/2019. Despite the existence of several treatment and contouring guidelines, we observed large variability of lymph node irradiation: The guideline recommendation for internal mammary irradiation is not consistently implemented in clinical practice and irradiation of the axilla after positive SLNB (sentinel lymph node biopsy) or ALND (axillary lymph node dissection) is handled very differently. Furthermore, in most clinics, the ESTRO (European Society for Therapeutic Radiology and Oncology) contouring consensus is not used, and PTV (planning target volume) definitions and margins vary considerably. CONCLUSION: Further clinical studies should be performed with a particular focus on radiotherapy for lymphatic drainage to support and amend the existing guidelines. These studies should establish a more standardized treatment of the lymph node regions in clinical practice. Quality assurance should enforce broad implementation of consensus recommendations.

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Bortezomib is a potent drug for the treatment of multiple myeloma. Its anti-tumor activity is mediated by proteasome inhibition leading to decreased cell proliferation and induction of apoptosis. However, an unimpaired proteasomal function plays a crucial role for the induction of anti-tumor immunity by dendritic cells (DCs), which are currently used for therapeutic vaccination against various tumors including myeloma. In the present study, we investigated the impact of bortezomib on the immunostimulatory capacity of 6-sulfo LacNAc (slan) DCs, which represent a major subset of human blood DCs. We demonstrated that this proteasome inhibitor efficiently impairs the spontaneous in vitro maturation of slanDCs and the release of tumor necrosis factor (TNF)-alpha as well as interleukin (IL)-12 upon lipopolysaccharide (LPS) stimulation. Functional data revealed that bortezomib profoundly inhibits slanDC-induced proliferation and differentiation of CD4(+) T cells. In addition, the capacity of slanDCs to promote interferon-gamma secretion and tumor-directed cytotoxicity of natural killer (NK) cells is markedly impaired by bortezomib. These results provide evidence that bortezomib significantly reduces the ability of native human blood DCs to regulate innate and adaptive anti-tumor immunity and may have implications for the design of therapeutic strategies combining DC vaccination and bortezomib treatment.

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