Fusion of human monocarboxylate transporter 1 with basigin and expression in S. cerevisiae: Is basigin more than a chaperone?

Lactate is a key metabolite in human cells. A regulated transport across membranes is vital for cellular function while deregulated transport is a hallmark of cancer. In tumor cells, glycolysis as the main route for ATP synthesis even in the presence of oxygen (Warburg effect) demands rapid lactate clearance to avoid acidification. Oxygenic cancer cells, in turn, rely on an efficient retrieval of extracellular lactate to fuel the citric acid cycle (reverse Warburg effect). To maintain an active interchange between cells, four monocarboxylate transporters (MCT1−4) manage bi-directional, proton-coupled transport across plasma membranes. For its translocation to the plasma membrane, MCT1 demands chaperoning by a member of the immunoglobulin superfamily, namely basigin. Both proteins remain complexed at the plasma membrane. Although frequently suggested, a direct effect of the chaperone on MCT1-mediated transport is not resolvable in commonly used expression systems. In this study, MCT1 expression in S. cerevisiae Δjen1 Δady2 profited from a basigin-independent translocation in a system with zero background from endogenous monocarboxylate transporters or basigin homologs. The molecular fusion with truncated basigin constructs revealed an effect on transmembrane L-lactate distribution at the domain level. In zero-trans influx experiments using 14C-labeled substrate, the presence of basigin’s extracellular Ig-I domain permitted a 4.5-fold intracellular L-lactate accumulation in the transport equilibrium. At near-neutral pH, cytosolic L-lactate concentrations greatly exceeded those provided with the buffer. The absence of the basigin Ig-I domain due to truncation or misfolding reversed this effect. The identification of patches of positive and negative surface potentials and evidence from charge-resolving point mutations indicated an electrostatic attraction of L-lactate anions and protons. This thesis deduces a substrate harvesting function of basigin that creates a “microenvironment” of locally increased concentrations and drives L-lactate influx according to Le Chatelier’s principle. This influx was physiologically relevant and promoted cell growth on L-lactate medium. According to classical and reverse Warburg effects, highly adapted tumor cells require a fine-tuned transmembrane L-lactate distribution and basigin might be an important determinant. Hereof, MCTs are promising targets in the anti-tumor therapy. The basigin-MCT1 fusion set-up from this study further revealed two known MCT1 inhibitors, AZD3965 and p-chloromercuribenzene sulfonate (pCMBS), as direct and basigin-independent modifiers. Cys159 in the transporter cavity was revealed as selectively targetable by pCMBS leading to a complete transport inhibition. Smaller cysteine-modifiers had a less prominent effect and lacked site-specificity. Cys159 is proposed to constitute a hinge region of the alternating access transporter and a wedge-like modification locks MCT1 in the outward open conformation. This reveals a target region for inhibitor design and in the future, Cys159 might serve as a natural anchor to introduce distinct labels and report on physicochemical modalities in a most critical part of the transporter

Johanna Hofmann-Stirnemann. The first female museum director in Germany

In 1930, Germany’s first publicly appointed female museum director took office: Hanna Stirnemann took over as director of the Jena City Museum that year. As museum director, she was a pioneer in a profession that had been defined by men until then. This article traces her museum career, which took her from the Oldenburg State Museum to the Reussisches Heimatmuseum in Greiz and finally to the Jena City Museum. There, she quickly made a name for herself as a museum director and outstanding art historian with a fine sense for an innovative exhibition and event program. The article will also show what happened after Stirnemann was forced to resign from her post by the National Socialists in 1935. After the war, the politically ‘unencumbered’ art historian was rehabilitated as mayor of a small town as well as director of the Rudolstadt Castle Museum and acting director of the Goethe and Schiller Archives in Weimar. In order to escape the restrictive cultural policy of the GDR, she moved to West-Berlin in 1950

Acquiring high-resolution wind measurements by modifying radiosonde sounding procedures

High-resolution wind measurements are crucial for the understanding of dynamic processes in the atmosphere. In the troposphere and lower stratosphere, radiosondes provide a good vertical resolution of a few metres, but the wind data are usually low-pass filtered by the manufacturer in order to suppress disturbances in the data caused by the spurious motions of the sonde. As an example, the filter within the standard processing of Vaisala radiosondes becomes effective at vertical scales below 300 m for an ascent rate of 5 m s−1. We describe a method for increasing the usable resolution of radiosonde wind measurements. The main ideas are to avoid self-induced motions of the balloon by keeping it in the subcritical Reynolds number range, to avoid typical pendulum motions of a 15 s period by using a shorter string, and to use data from a descending balloon in order to avoid disturbances from the wake of the balloon affecting temperature and humidity measurements due to the decreased string length. We demonstrate that our changes in hardware and software allow for artefact-free wind data down to scales of 50 m, while the remaining disturbances on even smaller scales are removed. Accordingly, the usable resolution of the wind data has been increased by a factor of 6, compared to the standard data output, at relatively low cost.</p

The Doppler wind, temperature, and aerosol RMR lidar system at Kühlungsborn, Germany – Part 1: Technical specifications and capabilities

This paper describes the technical specifications of the extensions made to the middle-atmospheric lidar facility at the Leibniz Institute of Atmospheric Physics in Kühlungsborn, Germany (54.12° N, 11.77° E). The upgrade complements the existing daylight-capable Rayleigh–Mie–Raman (RMR) temperature lidar with a nighttime-only RMR wind–temperature lidar. The new system comprises an independent lidar with laser, telescopes, and detectors, which is synchronized with and adapted to the (old) temperature lidar. As a result, with the combination of RMR lidars the atmosphere is probed with three (vertical and tilted) beams. This work intends to highlight the recent innovations in the construction of a Doppler–Rayleigh lidar system using the single-edge iodine-cell technique, which allows for the simultaneous measurement of wind, temperature, and aerosols. We will detail supporting subsystems that allow for a high degree of lidar automation and concisely provide key technical information about the system that will support readers in the development of additional RMR wind–temperature lidar systems. We show an example of time-resolved temperature and wind soundings reaching up to ∼ 90 km. These data agree well with ECMWF-IFS profiles between 35 and ∼ 50 km but show a much larger variability above. In the companion article, we will present the algorithm design and uncertainty budgets associated with the data processing chain.</p

Lipid-Iron Nanoparticle with a Cell Stress Release Mechanism Combined with a Local Alternating Magnetic Field Enables Site-Activated Drug Release

Simple Summary A novel active release system magnetic sphingomyelin-containing liposome encapsulated with indocyanine green, fluorescent marker, or the anticancer drug cisplatin was evaluated. The liposomal sphingomyelin is a target for the sphingomyelinase enzyme, which is released by stressed cells. Thus, sphingomyelin containing liposomes behave as a sensitizer for biological stress situations. In addition, the liposomes were engineered by adding paramagnetic beads to act as a receiver of outside given magnetic energy. The enzymatic activity towards liposomes and destruction caused by the applied magnetic field caused the release of the content from the liposomes. By using these novel liposomes, we could improve the drug release feature of liposomes. The improved targeting and drug-release were shown in vitro and the orthotopic tongue cancer model in mice optical imaging. The increased delivery of cisplatin prolonged the survival of the targeted delivery group versus free cisplatin. Most available cancer chemotherapies are based on systemically administered small organic molecules, and only a tiny fraction of the drug reaches the disease site. The approach causes significant side effects and limits the outcome of the therapy. Targeted drug delivery provides an alternative to improve the situation. However, due to the poor release characteristics of the delivery systems, limitations remain. This report presents a new approach to address the challenges using two fundamentally different mechanisms to trigger the release from the liposomal carrier. We use an endogenous disease marker, an enzyme, combined with an externally applied magnetic field, to open the delivery system at the correct time only in the disease site. This site-activated release system is a novel two-switch nanomachine that can be regulated by a cell stress-induced enzyme at the cellular level and be remotely controlled using an applied magnetic field. We tested the concept using sphingomyelin-containing liposomes encapsulated with indocyanine green, fluorescent marker, or the anticancer drug cisplatin. We engineered the liposomes by adding paramagnetic beads to act as a receiver of outside magnetic energy. The developed multifunctional liposomes were characterized in vitro in leakage studies and cell internalization studies. The release system was further studied in vivo in imaging and therapy trials using a squamous cell carcinoma tumor in the mouse as a disease model. In vitro studies showed an increased release of loaded material when stress-related enzyme and magnetic field was applied to the carrier liposomes. The theranostic liposomes were found in tumors, and the improved therapeutic effect was shown in the survival studies.Peer reviewe

Adjuvante Chemotherapie im UICC-Stadium II und III bei Patienten mit Lynch-Syndrom (HNPCC)

Ziel dieser Arbeit war die Untersuchung der Effektivität einer adjuvanten Chemotherapie bei Patienten mit HNPCC. Untersucht wurden 452 Patienten mit Lynch-Syndrom (UICC-Stadium II: 61,5%, Stadium III: 38,5%). Endpunkte: Gesamtüberleben (OS), kolonkarzinomspezifisches Überleben (KRK-S) und krankheitsfreies Überleben (DFS). Ergebnis: UICC-Stadium II: In allen drei Endpunkten kein signifikanter Unterschied zwischen adjuvant chemotherapierter und ausschließlich operierter Patientengruppe. Stadium IIB: Trend zum ungünstigeren Verlauf für die mit 5-FU behandelten Patienten (n=19), im Gegensatz zu der ausschließlich operierten Patientengruppe (n=12) für die Endpunkte OS und KRK-S. Darüber hinaus kein signifikanter Unterschied hinsichtlich der applizierten Chemotherapie (5-FU vs. FOLFOX). UICC-Stadium III: Signifikant günstigerer Verlauf für die chemotherapierten Patienten für OS und KRK-S und im Trend für DFS. Keine prognostischen Unterschiede zwischen 5-FU-basierter und FOLFOX-Chemotherapie

Acquiring high-resolution wind measurements by modifying radiosonde sounding procedures

High-resolution wind measurements are crucial for the understanding of dynamic processes in the atmosphere. In the troposphere and lower stratosphere, radiosondes provide a good vertical resolution of a few metres, but the wind data are usually low-pass filtered by the manufacturer in order to suppress disturbances in the data caused by the spurious motions of the sonde. As an example, the filter within the standard processing of Vaisala radiosondes becomes effective at vertical scales below 300 m for an ascent rate of 5 m s−1. We describe a method for increasing the usable resolution of radiosonde wind measurements. The main ideas are to avoid self-induced motions of the balloon by keeping it in the subcritical Reynolds number range, to avoid typical pendulum motions of a 15 s period by using a shorter string, and to use data from a descending balloon in order to avoid disturbances from the wake of the balloon affecting temperature and humidity measurements due to the decreased string length. We demonstrate that our changes in hardware and software allow for artefact-free wind data down to scales of 50 m, while the remaining disturbances on even smaller scales are removed. Accordingly, the usable resolution of the wind data has been increased by a factor of 6, compared to the standard data output, at relatively low cost

Psychological and work-related outcomes after inpatient multidisciplinary rehabilitation of chronic low back pain: a prospective randomized controlled trial

Abstract Background This study investigated the long-term effects (12 months post-rehabilitation) of a standard inpatient multidisciplinary rehabilitation program for patients with chronic low back pain (CLBP), in which a control group (CG) received pain competence training and an intervention group (IG) received combined pain competence and depression prevention training. Methods In this prospective control group study with cluster-block randomization, a total of n = 583 patients were included into per protocol analyses. To examine the effects of rehabilitation on depressive symptoms, pain self-efficacy, and work ability, patients were stratified in repeated-measures analyses of variance by treatment condition (IG vs. CG), level of depressive symptoms (low vs. high), and time of assessment (pre, post, 6, and 12 months after rehabilitation). The impact of each treatment on pain-related days of sick leave (DSL; dichotomized into ≤ vs. > 2 weeks) was determined separately by conducting non-parametric analyses. Multiple imputations (n = 1225) confirmed the results. Effects were interpreted if clinical significance was given. Results Only patients with high levels of depressive symptoms showed long-term improvements in depressive symptoms and self-efficacy. Long-term improvements in work ability index and mental work ability item were restricted to the IG. Furthermore, long-term effects on pain-related DSL were ascertained by per protocol and multiple imputation analyses only for the IG. Conclusions Patients with high levels of depressive symptoms showed improvements in depressive symptoms and self-efficacy, supporting the psychological effectiveness of both interventions. However, the beneficial long-term effects of rehabilitation on work ability and pain-related DSL among the IG support implementation of combined pain competence and depression prevention training. Trial registration DRKS00015465 (German Clinical Trial Register DRKS); date of registration: 03.09.2018