Effect of Particle Wettability and Particle Concentration on the Enzymatic Dehydration of n-Octanaloxime in Pickering Emulsions

© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH Pickering emulsion systems have emerged as platforms for the synthesis of organic molecules in biphasic biocatalysis. Herein, the catalytic performance was evaluated for biotransformation using whole cells exemplified for the dehydration of n-octanaloxime to n-octanenitrile catalysed by an aldoxime dehydratase (OxdB) overexpressed in E. coli. This study was carried out in Pickering emulsions stabilised solely with silica particles of different hydrophobicity. We correlate, for the first time, the properties of the emulsions with the conversion of the reaction, thus gaining an insight into the impact of the particle wettability and particle concentration. When comparing two emulsions of different type with similar stability and droplet diameter, the oil-in-water (o/w) system displayed a higher conversion than the water-in-oil (w/o) system, despite the conversion in both cases being higher than that in a “classic” two-phase system. Furthermore, an increase in particle concentration prior to emulsification resulted in an increase of the interfacial area and hence a higher conversion

Gender-specific prevalence of pilonidal sinus disease over time: A systematic review and meta-analysis.

BACKGROUND Gender-specific risk factors have been suggested to promote a fourfold higher incidence of pilonidal sinus disease (PSD) in male as compared to female patients. However, in recent decades there has been an apparent shift towards an increasing prevalence of PSD in women, as body weight and other risk factors influence the disease. We aimed at determining whether PSD prevalence actually changed in men and women over time. METHODS Following PRISMA guidelines (PROSPERO ID: 42016051588), databases were systematically searched. Papers reporting on PSD published between 1833 and 2018 in English, French, German, Italian and Spanish containing precise numbers of male and female participants were selected for analysis. Gender-specific prevalence of PSD over several decades was the main outcome measure. RESULTS We screened 679 studies reporting on 104 055 patients and found that the male/female ratio in patients with PSD has remained constant over time, with women being affected in about 20% of all PSD cases (I2  = 96.18%; meta-regression p < 0.001). CONCLUSION While the prevalence of PSD has risen over the past decades, the ratio between affected males and affected females has remained constant, with women invariably representing about 20% of patients despite wide ranging socioeconomic and behavioural changes

Overcoming Work-Up Limitations of Biphasic Biocatalytic Reaction Mixtures Through Liquid-Liquid Segmented Flow Processes

Adebar N, Choi J-E, Schober L, et al. Overcoming Work-Up Limitations of Biphasic Biocatalytic Reaction Mixtures Through Liquid-Liquid Segmented Flow Processes. ChemCatChem. 2019;11(23):5788-5793.Biphasic biocatalytic reactions have gained much attention in the field of enzyme-catalysed synthesis. As most components being of relevance for the pharmaceutical industry are hydrophobic, often biphasic reaction media turned out to be the solvent system of choice. However, in spite of successful reaction courses practical difficulties in the downstream-processing, in particular extremely difficult phase separations due to emulsification and precipitation, represent a challenge to overcome in process development. In this work, we report our studies on the benefits of a simple flow set-up being capable to minimise such work-up limitations. In detail, a segmented flow system based on a biphasic MTBE/buffer mixture was successfully applied for two types of enzymatic reductions of a hydrophobic ketone in the presence of an alcohol dehydrogenase (ADH) as an enzyme class being known for their excellent enantioselectivity and successful utilization in the synthesis of a range of active pharmaceutical ingredients. The applicability of this flow system was demonstrated with two different enzymes as well as different substrates. Besides an ADH from Lactobacillus brevis, an ADH from Ogatea minuta was utilized for the reduction of acetophenone and 2,2,2-trifluoroacetophenone, respectively

Switchable Signaling Molecules for Media Modulation: Fundamentals, Applications, and Research Directions

Although visionary applications of molecular communication (MC), such as long-term continuous health monitoring by cooperative in-body nanomachines, have been proposed, MC is still in its infancy when it comes to practical implementation. In particular, long-term experiments and applications face issues such as depletion of signaling molecules (SMs) at the transmitter (TX) and inter-symbol interference (ISI) at the receiver (RX). To overcome these practical challenges, a new class of SMs with switchable states seems to be promising for future MC applications. In this work, we provide an overview of existing switchable SMs, and classify them according to their properties. Furthermore, we highlight how switchable SMs can be utilized as information carriers for media modulation. In addition, we present theoretical and experimental results for an end-to-end MC system employing the green fluorescent protein variant "Dreiklang" (GFPD) as switchable SM. Our experimental results show, for the first time, successful information transmission in a closed-loop pipe system using media modulation. Finally, we discuss media modulation specific challenges and opportunities.Comment: 7 pages, 6 figures. This work has been accepted for publication in IEEE Communications Magazin

Acute Effects of Single Versus Combined Inhaled β2-Agonists Salbutamol and Formoterol on Time Trial Performance, Lung Function, Metabolic and Endocrine Variables

Background High prevalence rates of β2-agonist use among athletes in competitive sports makes it tempting to speculate that illegitimate use of β2-agonists boosts performance. However, data regarding the potential performance-enhancing effects of inhaled β2-agonists and its underlying molecular basis are scarce. Methods In total, 24 competitive endurance athletes (12f/12m) participated in a clinical double-blinded balanced four-way block cross-over trial to investigate single versus combined effects of β2-agonists salbutamol (SAL) and formoterol (FOR), to evaluate the potential performance enhancement of SAL (1200 µg, Cyclocaps, Pb Pharma GmbH), FOR (36 µg, Sandoz, HEXAL AG) and SAL + FOR (1200 µg + 36 µg) compared to placebo (PLA, Gelatine capsules containing lactose monohydrate, Pharmacy of the University Hospital Ulm). Measurements included skeletal muscle gene and protein expression, endocrine regulation, urinary/serum β2-agonist concentrations, cardiac markers, cardiopulmonary and lung function testing and the 10-min time trial (TT) performance on a bicycle ergometer as outcome variables. Blood and urine samples were collected pre-, post-, 3 h post- and 24 h post-TT. Results Mean power output during TT was not different between study arms. Treatment effects regarding lung function (p < 0.001), echocardiographic (left ventricular end-systolic volume p = 0.037; endocardial global longitudinal strain p < 0.001) and metabolic variables (e.g. NR4A2 and ATF3 pathway) were observed without any influence on performance. In female athletes, total serum β2-agonist concentrations for SAL and FOR were higher. Microarray muscle gene analysis showed a treatment effect for target genes in energy metabolism with strongest effect by SAL + FOR (NR4A2; p = 0.001). Of endocrine variables, follicle-stimulating hormone (3 h Post–Post-TT), luteinizing hormone (3 h Post–Pre-TT) and insulin (Post–Pre-TT) concentrations showed a treatment effect (all p < 0.05). Conclusions No endurance performance-enhancing effect for SAL, FOR or SAL + FOR within the permitted dosages compared to PLA was found despite an acute effect on lung and cardiac function as well as endocrine and metabolic variables in healthy participants. The impact of combined β2-agonists on performance and sex-specific thresholds on the molecular and cardiac level and their potential long-term performance enhancing or health effects have still to be determined. Trial registration: Registered at Eudra CT with the number: 2015-005598-19 (09.12.2015) and DRKS with number DRKS00010574 (16.11.2021, retrospectively registered)

Experimental Research in Synthetic Molecular Communications -- Part I: Overview and Short-Range Systems

Since its emergence from the communication engineering community around one and a half decades ago, the field of Synthetic Molecular Communication (SMC) has experienced continued growth, both in the number of technical contributions from a vibrant community and in terms of research funding. Throughout this process, the vision of SMC as a novel, revolutionary communication paradigm has constantly evolved, driven by feedback from theoretical and experimental studies, respectively. It is believed that especially the latter ones will be crucial for the transition of SMC towards a higher technology readiness level in the near future. In this spirit, we present here a comprehensive survey of experimental research in SMC. In particular, this survey focuses on highlighting the major drivers behind different lines of experimental research in terms of the respective envisioned applications. This approach allows us to categorize existing works and identify current research gaps that still hinder the development of practical SMC-based applications. Our survey consists of two parts; this paper and a companion paper. While the companion paper focuses on SMC with relatively long communication ranges, this paper covers SMC over short distances of typically not more than a few millimeters.Comment: 10 pages, 1 table, 5 figures. Accepted for publication in the IEEE Nanotechnology Magazin

Experimental Research in Synthetic Molecular Communications -- Part II: Long-Range Communication

In this second part of our survey on experimental research in Synthetic Molecular Communication (SMC), we review works on long-range SMC systems, i.e., systems with communication ranges of more than a few millimeters. Despite the importance of experimental research for the evolution of SMC towards a mature communication paradigm that will eventually support revolutionary applications beyond the reach of today's prevalent communication paradigms, the existing body of literature is still comparatively sparse. Long-range SMC systems have been proposed in the literature for information transmission in two types of fluid media, liquid and air. While both types of SMC systems, liquid-based and air-based systems, rely on encoding and transmitting information using molecules, they differ substantially in terms of the physical system designs and in the type of applications they are intended for. In this paper, we present a systematic characterization of experimental works on long-range SMC that reveals the major drivers of these works in terms of the respective target applications. Furthermore, the physical designs for long-range SMC proposed in the literature are comprehensively reviewed. In this way, our survey will contribute to making experimental research in this field more accessible and identifying novel directions for future research.Comment: 10 pages, 2 tables, 4 figures. Accepted for publication in the IEEE Nanotechnology Magazin

The challenges of measuring social cohesion in public health research: A systematic review and ecometric meta-analysis

The relationship between social cohesion and health has been studied for decades. Yet, due to the contextual nature of this concept, measuring social cohesion remains challenging. Using a meta-analytical framework, this review's goal was to study the ecometric measurement properties of social cohesion in order to describe dissimilarities in its measurement as well as bring a new perspective on the empirical usefulness of the concept itself. To this end, we analysed if, and to what extent, contextual-level reliability and intersubjective agreement of 78 social cohesion measurements varied under different measurement conditions like measurement instrument, spatial unit, ecometric model specification, or region. We found consistent evidence for the contextual nature of social cohesion, however, most variation existed between individuals, not contexts. While contextual dependence in response behaviour was fairly insensitive to item choices, population size within chosen spatial units of social cohesion measurements mattered. Somewhat counterintuitively, using spatial units with, on average, fewer residents did not yield systematically superior ecometric properties. Instead, our results underline that precise theory about the relevant contextual units of causal relationships between social cohesion and health is vital and cannot be replaced by empirical analysis. Although adjustment for respondent's characteristics had only small effects on ecometric properties, potential pitfalls of this analytic strategy are discussed in this paper. Finally, acknowledging the sensitivity of measuring social cohesion, we derived recommendations for future studies investigating the effects of contextual-level social characteristics on health