Publications by authors named "Wittmann S"

Background: There is increasing evidence that nitric oxide (nitrogen monoxide, NO) significantly influences immune cellular responses, including those from polymorphonuclear leukocytes (PMNs).

Objective: The aim of this study was to examine a possible effect of NO on PMNs' function (chemotaxis, production of reactive oxygen species (ROS), and NETosis) using live cell imaging. Moreover, we investigated PMN surface epitope and neutrophil oxidative burst under the influence of NO by flow cytometric analysis.

View Article and Find Full Text PDF

The synthesis of bis-lactone and butenolide derivatives was described using alkylidene Meldrum's acid as nucleophiles. The process operates in a triple cascade through an auto tandem catalysis promoted by DBU.

View Article and Find Full Text PDF
Article Synopsis
  • Heme oxygenase-1 (HO-1) is an enzyme that breaks down heme into important byproducts like iron, carbon monoxide, and biliverdin-IXa, functioning in various physiological and pathological processes, especially in the digestive system.
  • The review covers HO-1's structure, regulatory mechanisms, and compares it with another isoform, HO-2, while emphasizing the dual role of HO-1 in providing cytoprotection and potential pro-inflammatory effects.
  • The significance of HO-1 in cancer, particularly colorectal cancer, is also discussed, highlighting how it influences tumor growth and progression through various biological pathways such as oxidative stress and cell cycle control.
View Article and Find Full Text PDF

Despite recent advances in cryo-electron microscopy and artificial intelligence-based model predictions, a significant fraction of structure determinations by macromolecular crystallography still requires experimental phasing, usually by means of single-wavelength anomalous diffraction (SAD) techniques. Most synchrotron beamlines provide highly brilliant beams of X-rays of between 0.7 and 2 Å wavelength.

View Article and Find Full Text PDF

Background: Cancer patients often use complementary and alternative medicine (CAM), however, standardized assessment in clinical routine is missing. The aim of this study was to evaluate a screening questionnaire on CAM usage that was published in the S3 Guideline Complementary Medicine in the Treatment of Oncological Patients.

Methods: We developed a survey questionnaire to assess the practicability of the guideline questionnaire and communication on CAM between health care providers (HCPs) and patients.

View Article and Find Full Text PDF

Background: Child mortality is high in Ethiopia, but reliable data on the causes of death are scarce. We aimed to gather data for the contributory causes of stillbirth and child deaths in eastern Ethiopia.

Methods: In this population-based post-mortem study, we established a death-notification system in health facilities and in the community in Kersa (rural), Haramaya (rural) and Harar (urban) in eastern Ethiopia, at a new site of the Child Health and Mortality Prevention Surveillance (CHAMPS) network.

View Article and Find Full Text PDF

The intracellular restriction factor TRIM5α inhibits endogenous LINE-1 retroelements. It induces innate immune signaling cascades upon sensing of cytoplasmic LINE-1 complexes, thereby underlining its importance for protecting the human genome from harmful retrotransposition events. Here, we show that a frequent SNP within the RING domain of TRIM5α, resulting in the variant H43Y, blocks LINE-1 retrotransposition with higher efficiency compared to TRIM5α WT.

View Article and Find Full Text PDF
Article Synopsis
  • Centrifugation, a common method for isolating neutrophils, may negatively impact their functionality, suggesting prior research could be biased.
  • Researchers hypothesized that gently isolated neutrophils, instead of undergoing NETosis, actually exhibit a natural process of apoptosis over time.
  • Through live-cell imaging, it was found that neutrophils can retain significant migratory activity for over six days when isolated without centrifugation, indicating the importance of using native cells in future studies.
View Article and Find Full Text PDF
Article Synopsis
  • Clinical algorithms for assessing febrile children often rely on vital sign thresholds that may not accurately reflect serious bacterial infections (SBI) after antipyretics are given.
  • A study involving 740 children demonstrated that persistent tachypnoea (fast breathing) after temperature reduction is a significant predictor of pneumonia but does not apply to other types of SBI.
  • Tachypnoea showed high specificity and likelihood ratios for ruling in pneumonia, while tachycardia (fast heart rate) proved to be a poor diagnostic indicator, suggesting a need to reconsider its use in discharge decisions.
View Article and Find Full Text PDF

Centrifugation is a common step in most of the popular protocols for the isolation of neutrophils from whole blood. Inconsistent results from previous studies on neutrophils may originate from an underestimation of the centrifugation effect, as in consequence impaired, not native cells, being investigated. We hypothesize, that centrifugation significantly impairs major neutrophil functions.

View Article and Find Full Text PDF

Background: Predictors of poor outcome associated with variceal bleeding remain suboptimal. In patients with cirrhosis, serum lactate combined with Model for End-Stage Liver Disease (MELD-LA) improved prediction across heterogeneous populations. However, prognostic properties have not yet been assessed in the context of variceal bleeding.

View Article and Find Full Text PDF

Methylation of the mRNA 5' cap by cellular methyltransferases enables efficient translation and avoids recognition by innate immune factors. Coronaviruses encode viral 2'-O-methyltransferases to shield their RNA from host factors. Here, we generate recombinant SARS-CoV-2 harboring a catalytically inactive 2'-O-methyltransferase Nsp16, Nsp16mut, and analyze viral replication in human lung epithelial cells.

View Article and Find Full Text PDF
Article Synopsis
  • The SARS-CoV-2 infection cycle involves complex interactions between the virus and the host, which can be disrupted using targeted antiviral drugs.
  • Researchers repurposed existing antiviral medications to inhibit key enzymes necessary for the virus’s replication, especially focusing on the methylation of the viral RNA cap.
  • A promising bispecific inhibitor was identified that targets vital enzymes, alongside another compound named DZNep, which shows antiviral effects and potential to reduce harmful inflammation in COVID-19 cases.
View Article and Find Full Text PDF

The epithelial sodium channel (ENaC) is a heterotrimer consisting of α-, β-, and γ-subunits. Channel activation requires proteolytic release of inhibitory tracts from the extracellular domains of α-ENaC and γ-ENaC; however, the proteases involved in the removal of the γ-inhibitory tract remain unclear. In several epithelial tissues, ENaC is coexpressed with the transmembrane serine protease 2 (TMPRSS2).

View Article and Find Full Text PDF

Background: Sleep-disordered breathing (SDB) is associated with increased oxidant generation. Oxidized Ca/calmodulin kinase II (CaMKII) can contribute to atrial arrhythmias by the stimulation of sarcoplasmic reticulum Ca release events, i.e.

View Article and Find Full Text PDF

Background: Clinically suspected and laboratory-confirmed bloodstream infections are frequent causes of morbidity and mortality during neonatal care. The most effective infection prevention and control interventions for neonates in low- and middle-income countries (LMIC) are unknown.

Aim: To identify effective interventions in the prevention of hospital-acquired bloodstream infections in LMIC neonatal units.

View Article and Find Full Text PDF

Colorectal cancer is one of the most frequent tumor entities, with an increasing incidence and mortality in younger adults in Europe and the United States. Five-year survival rates for advanced colorectal cancer are still low, highlighting the need for novel targets in colorectal cancer therapy. Here, we investigated the therapeutic potential of the compound devimistat (CPI-613) that targets altered mitochondrial cancer cell metabolism and its synergism with the antineoplastic drugs 5-fluorouracil (5-FU) and irinotecan (IT) in colorectal cancer.

View Article and Find Full Text PDF

Upon Brønsted base organocatalysis, ketone-derived alkylidene Meldrum's acids proved to be competent vinylogous platforms able to undergo a formal (4+2) cycloaddition reaction with dihydro-2,3-furandione, providing an unprecedented route to 3,6-dihydropyran-2-ones as spiro[4.5]decane derivatives with up to 98 % ee thanks to the commercially available Takemoto catalyst. Preliminary investigation showed that this reaction could be extended to other activated ketones, establishing these alkylidene Meldrum's acids as a novel C4-synthon in the vinylogous series.

View Article and Find Full Text PDF

Liquid-liquid phase separation of proteins underpins the formation of membraneless compartments in living cells. Elucidating the molecular driving forces underlying protein phase transitions is therefore a key objective for understanding biological function and malfunction. Here we show that cellular proteins, which form condensates at low salt concentrations, including FUS, TDP-43, Brd4, Sox2, and Annexin A11, can reenter a phase-separated regime at high salt concentrations.

View Article and Find Full Text PDF

Introduction: Local anesthetics (LAs) are frequently used during anesthesia; however, they may influence granulocyte function which in turn could modify immune responses in the perioperative period. Therefore, the aim of this study was to investigate the impact of clinically used doses of bupivacaine and lidocaine on granulocyte function with regard to migration, reactive oxygen species (ROS) production, neutrophil extracellular traps (NETosis) formation, and viability.

Methods: A total of 38 granulocyte-enriched samples from healthy subjects were obtained by whole blood lysis.

View Article and Find Full Text PDF

Inhibition of multiple enzymes of the arachidonic acid cascade leads to synergistic anti-inflammatory effects. Merging of 5-lipoxygenase (5-LOX) and soluble epoxide hydrolase (sEH) pharmacophores led to the discovery of a dual 5-LOX/sEH inhibitor, which was subsequently optimized in terms of potency toward both targets and metabolic stability. The optimized lead structure displayed cellular activity in human polymorphonuclear leukocytes, oral bioavailability, and target engagement in vivo and demonstrated profound anti-inflammatory and anti-fibrotic efficiency in a kidney injury model caused by unilateral ureteral obstruction in mice.

View Article and Find Full Text PDF