Publications by authors named "Mayer P"

Lanthanides (Ln) are critical raw materials, however, their mining and purification have a considerable negative environmental impact and sustainable recycling and separation strategies for these elements are needed. In this study, the precipitation and solubility behavior of Ln complexes with pyrroloquinoline quinone (PQQ), the cofactor of recently discovered lanthanide (Ln) dependent methanol dehydrogenase (MDH) enzymes, is presented. In this context, the molecular structure of a biorelevant europium PQQ complex was for the first time elucidated outside a protein environment.

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The photophysical and photochemical properties of sulfoxide and sulfone derivatives of hemithioindigo photoswitches are scrutinized and compared to the unoxidized parent chromophores. Oxidation results in significantly blue-shifted absorptions and mostly reduction of photochromism while thermal stabilities of individual isomers remain largely unaltered. Effective photoswitching takes place at shorter wavelengths compared to parent hemithioindigos and high isomeric yields can be obtained reversibly in the respective photostationary states.

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Background: Clinicopathological features and surgical outcomes of patients with fibrolamellar hepatocellular carcinoma (FL-HCC) are underreported. The aim of this study is to describe clinical characteristics and surgical outcomes for patients with this rare tumor to raise awareness among clinicians and surgeons.

Methods: Retrospective review of records of a tertiary referral center and specialized liver unit was performed.

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The chemical composition of fossil soft tissues is a potentially powerful and yet underutilized tool for elucidating the affinity of problematic fossil organisms. In some cases, it has proven difficult to assign a problematic fossil even to the invertebrates or vertebrates (more generally chordates) based on often incompletely preserved morphology alone, and chemical composition may help to resolve such questions. Here, we use in situ Raman microspectroscopy to investigate the chemistry of a diverse array of invertebrate and vertebrate fossils from the Pennsylvanian Mazon Creek Lagerstätte of Illinois, and we generate a ChemoSpace through principal component analysis (PCA) of the in situ Raman spectra.

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Introduction: Pancreatoduodenectomy is the treatment of choice for a range of benign and malignant diseases. The pancreatic head must be separated from its supplying vessels, especially the gastroduodenal artery, during this operation. However, dissection of the gastroduodenal artery can disturb blood supply to the liver and result in liver ischemia.

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Oligoprogression (OPD) of non-small-cell lung cancer (NSCLC) occurs in approximately half of patients under targeted compounds (TKI) and facilitates use of regional therapies that can prolong survival. In order to characterize OPD in immunotherapy (IO)-treated NSCLC, we analyzed the failure pattern under PD-1/PD-L1 inhibitors ( = 297) or chemoimmunotherapy ( = 75). Under IO monotherapy, OPD was more frequent (20% vs.

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Purpose: Anastomotic leakage constitutes a dreaded complication after colorectal surgery, leading to increased morbidity and mortality as well as prolonged hospitalization. Most leakages become clinically apparent about 8 days after surgery; however, early detection is quintessential to reduce complications and to improve patients' outcome. We therefore investigated the significance of specific protein expression profiles as putative biomarkers, indicating anastomotic leakage.

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According to the currently accepted structure-property relationships, aceno-pentalenes with an angular shape (fused to the 1,2-bond of the acene) exhibit higher antiaromaticity than those with a linear shape (fused to the 2,3-bond of the acene). To explore and expand the current view, we designed and synthesized molecules where two isomeric, yet, different, 8π antiaromatic subunits, a benzocyclobutadiene (BCB) and a pentalene, are combined into, respectively, an angular and a linear topology via an unsaturated six-membered ring. The antiaromatic character of the molecules is supported experimentally by H NMR, UV-vis, and cyclic voltammetry measurements and X-ray crystallography.

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In the current study, improved exposure control and measurements were applied for the aquatic toxicity testing of a highly hydrophobic organic compound. The aim was to reliably determine the ecotoxicity of the model compound dodecylbenzene (DDB, Log K = 8.65) by applying passive dosing for aquatic toxicity testing exactly at the solubility limit.

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Purpose: To analyse 1000 consecutive patients, treated with isolated or combined posterior cruciate ligament (PCL) reconstruction in a single centre according to the epidemiological factors and differences in injury patterns depending on the activity during trauma.

Methods: Between 2004 and 2019, one thousand isolated and combined PCL reconstructions were performed. The medical charts and surgical reports of all patients were analysed regarding epidemiological factors.

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Objective: All arthroscopic treatment of deep cartilage defects in the knee for reconstruction of the articular surface.

Indications: Focal cartilage defects of the knee (ICRS ≥ grade 3) from a size of 2.5 cm and more.

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Petroleum products and essential oils are complex mixtures of hydrophobic and volatile chemicals and are categorized as substances of unknown or variable composition, complex reaction products, or biological materials (UVCBs). In aquatic testing and research of such mixtures, it is challenging to establish initial concentrations without the addition of cosolvents, to maintain constant concentrations during the test, and to keep a constant mixture composition in dilution series and throughout test duration. Passive dosing was here designed to meet these challenges by maximizing the surface area (/ = 3.

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Thiete dioxide units have been employed as a template for further functionalization through C-H activation strategies. Using simple thiete dioxide building blocks, a new library of axially chiral molecules has been synthesized that owe their stability to electrostatic interactions in the solid state. Similar starting materials were further engaged in the formation of cyclic trimeric structures, opening the pathway to unprecedented macrocyclic ring systems.

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The electrophilic reactivity of a series of 8-arylated vinyl -quinone methides (VQMs) was determined by analyzing the kinetics of their reactions with carbanions in DMSO at 20 °C according to the linear free energy relationship log = s( + ). The electrophilicity parameters for VQMs were used to successfully predict Michael-additions with structurally diverse C-, N-, S-, and H-nucleophiles.

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Lavigne GJ, Herrero Babiloni A, Mayer P, Daoust R, Martel MO. Thoughts on the 2019 American Academy of Sleep Medicine position statement on chronic opioid therapy and sleep. .

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Purpose: To determine and compare the incidence of postoperative septic arthritis following anterior cruciate ligament reconstruction (ACLR) with and without soaking of the graft in vancomycin solution prior to implantation in a large single-centre case series.

Methods: From 2004 to 2019, a total of 10,516 primary ACLR were performed and reviewed with regard to the occurrence of postoperative septic arthritis. From February 2017 onwards, all grafts were wrapped in a vancomycin-soaked (5 mg/ml) gauze swab between harvest and implantation (2294 patients, treatment group (2), prospectively followed).

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One of the primary functions of green roofs in urban areas is to moderate rainwater runoff, and one of the major impediments to the survival of plants on an extensive green roof (EGR) is a lack of available water during dry periods. Runoff moderation and water storage are both influenced by the composition of the growing media. Here we present a framework for evaluating the hydrologic performance of EGR growing media and also provide hydrologic attribute data for several commonly used EGR media constituents.

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In contrast to natural and historical diets of wild and domesticated ruminants, the diversity of plant species is limited in diets of modern dairy cows. Are "production diseases" linked to this? We conducted a trial to test the effects of a multicomponent herbal feed additive (HFA) on health, performance and fertility traits. A dose-finding study (DF) with 62 cows on 11 commercial farms compared a low (50 g) and a high (100 g) dose of HFA (HFA-50, HFA-100) with a placebo (PL).

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Purpose: To determine and compare the incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with autologous quadriceps tendon (with patellar bone block) compared to autologous hamstring tendons (semitendinosus and gracilis).

Methods: A total of 1638 isolated R-ACLR with either autologous hamstring tendons (n = 1004, 61.3%) or quadriceps tendon (n = 634; 38.

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Diffusion-weighted magnetic resonance imaging (DW-MRI) is a diagnostic tool that is increasingly used for the detection and characterization of focal masses in the abdomen, among these, pancreatic ductal adenocarcinoma (PDAC). DW-MRI reflects the microarchitecture of the tissue, and changes in diffusion, which are reflected by changes in the apparent diffusion coefficient (ADC), are mainly attributed to variations in cellular density, glandular formation, and fibrosis. When analyzing the T cell infiltrates, we found an association of a tumor-promoting subpopulation, characterized by the expression of interleukin (IL) 21 and IL26, with high ADC values.

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Light-driven molecular motors possess immense potential as central driving units for future nanotechnology. Integration into larger molecular setups and transduction of their mechanical motions represents the current frontier of research. Herein we report on an integrated molecular machine setup allowing the transmission of potential energy from a motor unit onto a remote receiving entity.

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The June 2019 workshop 21st Century Approaches for Evaluating Exposures, Biological Activity, and Risks of Complex Substances, co-organised by the International Council of Chemical Association's Long-Range Research Initiative and the European Commission's Joint Research Centre, is summarised. Focus was the need for improved approaches to evaluate the safety of complex substances. Approximately 10% and 20% of substances registered under the EU chemicals legislation are 'multi-constituent substances' and 'substances of unknown or variable compositions, complex reaction products and biological substances' (UVCBs), respectively, and UVCBs comprise approximately 25% of the U.

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Microplastics released into freshwaters from anthropogenic sources settle in the sediments, where they may pose an environmental threat to benthic organisms. However, few studies have considered the ecotoxicological hazard of microplastic particles for nematodes, one of the most abundant taxa of the benthic meiofauna. This study investigated the toxic effects of polystyrene (PS) beads (0.

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Introduction: Portable monitoring (PM) is an alternative to laboratory polysomnography (PSG) for diagnosing obstructive sleep apnea (OSA). However, PM tends to underestimate the apnea-hypopnea index (AHI), as it does not identify non-desaturating events associated with electroencephalographic (EEG) arousal. The objectives were to explore heart rate acceleration (HRa) and decrease in pulse transit time (PTT) as surrogates to EEG arousal for non-desaturating hypopnea and respiratory effort-related arousal (RERA), and to estimate cut-off values for their use with both total sleep time (TST), the standard method for PSG, and total recording time (TRT), the usual method for PM.

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