LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 5092

Search options

  1. Article ; Online: N-acetylcysteine overcomes NF1 loss-driven resistance to PI3Kα inhibition in breast cancer.

    Auf der Maur, Priska / Trefny, Marcel P / Baumann, Zora / Vulin, Milica / Correia, Ana Luisa / Diepenbruck, Maren / Kramer, Nicolas / Volkmann, Katrin / Preca, Bogdan-Tiberius / Ramos, Pedro / Leroy, Cedric / Eichlisberger, Tobias / Buczak, Katarzyna / Zilli, Federica / Okamoto, Ryoko / Rad, Roland / Jensen, Michael Rugaard / Fritsch, Christine / Zippelius, Alfred /
    Stadler, Michael B / Bentires-Alj, Mohamed

    Cell reports. Medicine

    2023  Volume 4, Issue 4, Page(s) 101002

    Abstract: A genome-wide PiggyBac transposon-mediated screen and a resistance screen in a ... ...

    Abstract A genome-wide PiggyBac transposon-mediated screen and a resistance screen in a PIK3CA
    MeSH term(s) Humans ; Mice ; Animals ; Female ; Breast Neoplasms/drug therapy ; Breast Neoplasms/genetics ; Breast Neoplasms/metabolism ; Phosphatidylinositol 3-Kinase ; Acetylcysteine/pharmacology ; Class I Phosphatidylinositol 3-Kinases/genetics ; Phosphatidylinositol 3-Kinases/genetics
    Chemical Substances Alpelisib (08W5N2C97Q) ; Phosphatidylinositol 3-Kinase (EC 2.7.1.137) ; Acetylcysteine (WYQ7N0BPYC) ; Class I Phosphatidylinositol 3-Kinases (EC 2.7.1.137) ; Phosphatidylinositol 3-Kinases (EC 2.7.1.-)
    Language English
    Publishing date 2023-04-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2666-3791
    ISSN (online) 2666-3791
    DOI 10.1016/j.xcrm.2023.101002
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article: Optimized bisubstrate inhibitors for the actin N-terminal acetyltransferase NAA80.

    Myklebust, Line M / Baumann, Markus / Støve, Svein I / Foyn, Håvard / Arnesen, Thomas / Haug, Bengt Erik

    Frontiers in chemistry

    2023  Volume 11, Page(s) 1202501

    Abstract: Acetylation of protein N-termini is one of the most common protein modifications ... in the eukaryotic cell and is catalyzed by the N-terminal acetyltransferase family of enzymes. The N-terminal ... acetyltransferase NAA80 is expressed in the animal kingdom and was recently found to specifically N-terminally ...

    Abstract Acetylation of protein N-termini is one of the most common protein modifications in the eukaryotic cell and is catalyzed by the N-terminal acetyltransferase family of enzymes. The N-terminal acetyltransferase NAA80 is expressed in the animal kingdom and was recently found to specifically N-terminally acetylate actin, which is the main component of the microfilament system. This unique animal cell actin processing is essential for the maintenance of cell integrity and motility. Actin is the only known substrate of NAA80, thus potent inhibitors of NAA80 could prove as important tool compounds to study the crucial roles of actin and how NAA80 regulates this by N-terminal acetylation. Herein we describe a systematic study toward optimizing the peptide part of a bisubstrate-based NAA80 inhibitor comprising of coenzyme A conjugated onto the N-terminus of a tetrapeptide amide via an acetyl linker. By testing various combinations of Asp and Glu which are found at the N-termini of β- and γ-actin, respectively, CoA-Ac-EDDI-NH
    Language English
    Publishing date 2023-06-20
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2711776-5
    ISSN 2296-2646
    ISSN 2296-2646
    DOI 10.3389/fchem.2023.1202501
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article ; Online: In silico characterization of ligand-receptor interactions for U-47700, N,N-didesmethyl-U-47700, U-50488 at mu- and kappa-opioid receptors.

    Laus, Antonio / Kumar, Amit / Caboni, Pierluigi / De Luca, Maria A / Baumann, Michael H / Pieroni, Enrico / Tocco, Graziella

    Archiv der Pharmazie

    2023  Volume 356, Issue 9, Page(s) e2300256

    Abstract: ... In this regard, U-47700 (trans-3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide) and related "U ... molecular dynamics simulations to assess the nature of ligand-receptor interactions for U-47700, N,N-didesmethyl U ... groups from U-47700, to form N,N-didesmethyl U-47700, caused a loss of hydrogen bond contact ...

    Abstract The increasing misuse of novel synthetic opioids (NSOs) represents a serious public health concern. In this regard, U-47700 (trans-3,4-dichloro-N-[2-(dimethylamino)cyclohexyl]-N-methylbenzamide) and related "U-compounds" emerged on recreational drug markets as synthetic substitutes for illicit heroin and constituents of counterfeit pain medications. While the pharmacology of U-compounds has been investigated using in vitro and in vivo methods, there is still a lack of understanding about the details of ligand-receptor interactions at the molecular level. To this end, we have developed a molecular modeling protocol based on docking and molecular dynamics simulations to assess the nature of ligand-receptor interactions for U-47700, N,N-didesmethyl U-47700, and U-50488 at the mu-opioid receptor (MOR) and kappa-opioid receptor (KOR). The evaluation of ligand-receptor and ligand-receptor-membrane interaction energies enabled the identification of subtle conformational shifts in the receptors induced by ligand binding. Interestingly, the removal of two key methyl groups from U-47700, to form N,N-didesmethyl U-47700, caused a loss of hydrogen bond contact with tryptophan (Trp)229, which may underlie the lower interaction energy and reduced MOR affinity for the compound. Taken together, our results are consistent with the reported biological findings for U-compounds and provide a molecular basis for the MOR selectivity of U-47700 and KOR selectivity of U-50488.
    MeSH term(s) Receptors, Opioid, kappa/chemistry ; Receptors, Opioid, kappa/metabolism ; 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology ; Ligands ; Structure-Activity Relationship ; Receptors, Opioid, mu/metabolism ; Analgesics, Opioid/pharmacology ; Analgesics, Opioid/chemistry
    Chemical Substances Receptors, Opioid, kappa ; 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer (67198-13-4) ; U-47700 ; Ligands ; Receptors, Opioid, mu ; Analgesics, Opioid
    Language English
    Publishing date 2023-07-14
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 6381-2
    ISSN 1521-4184 ; 0365-6233 ; 1437-1014
    ISSN (online) 1521-4184
    ISSN 0365-6233 ; 1437-1014
    DOI 10.1002/ardp.202300256
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: First identification, chemical analysis and pharmacological characterization of N-piperidinyl etonitazene (etonitazepipne), a recent addition to the 2-benzylbenzimidazole opioid subclass.

    Vandeputte, Marthe M / Verougstraete, Nick / Walther, Donna / Glatfelter, Grant C / Malfliet, Jeroen / Baumann, Michael H / Verstraete, Alain G / Stove, Christophe P

    Archives of toxicology

    2022  Volume 96, Issue 6, Page(s) 1865–1880

    Abstract: N-Piperidinyl etonitazene ('etonitazepipne') represents a recent addition to the rapidly expanding ... different techniques (LC-HRMS, GC-MS, UHPLC-DAD, FT-IR) led to the unequivocal identification of N ... identification of N-piperidinyl etonitazene in authentic samples. LC-HRMS analysis revealed concentrations of 1 ...

    Abstract N-Piperidinyl etonitazene ('etonitazepipne') represents a recent addition to the rapidly expanding class of 2-benzylbenzimidazole 'nitazene' opioids. Following its first identification in an online-sourced powder and in biological samples from a patient seeking help for detoxification, this report details its in-depth chemical analysis and pharmacological characterization. Analysis of the powder via different techniques (LC-HRMS, GC-MS, UHPLC-DAD, FT-IR) led to the unequivocal identification of N-piperidinyl etonitazene. Furthermore, we report the first activity-based detection and analytical identification of N-piperidinyl etonitazene in authentic samples. LC-HRMS analysis revealed concentrations of 1.21 ng/mL in serum and 0.51 ng/mL in urine, whereas molecular networking enabled the tentative identification of various (potentially active) urinary metabolites. In addition, we determined that the extent of opioid activity present in the patient's serum was equivalent to the in vitro opioid activity exerted by 2.5-10 ng/mL fentanyl or 10-25 ng/mL hydromorphone in serum. Radioligand binding assays in rat brain tissue revealed that the drug binds with high affinity (K
    MeSH term(s) Analgesics, Opioid/chemistry ; Analgesics, Opioid/pharmacology ; Animals ; Benzimidazoles ; Fentanyl ; Humans ; Hydromorphone ; Male ; Powders ; Rats ; Rats, Sprague-Dawley ; Spectroscopy, Fourier Transform Infrared
    Chemical Substances Analgesics, Opioid ; Benzimidazoles ; Powders ; bendazole (26601THN1D) ; etonitazene (9U3GT3353T) ; Hydromorphone (Q812464R06) ; Fentanyl (UF599785JZ)
    Language English
    Publishing date 2022-04-21
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 124992-7
    ISSN 1432-0738 ; 0340-5761
    ISSN (online) 1432-0738
    ISSN 0340-5761
    DOI 10.1007/s00204-022-03294-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article ; Online: Phytoplankton physiology and functional traits under artificial upwelling with varying Si:N

    Ortiz Cortes, Joaquin / Aristegui, Javier / Goldenberg, Silvan / Fernandez-Mendez, Mar / Taucher, Jan / Archer, Stephen D. / Baumann, Moritz / Riebesell, Ulf

    2024  

    Abstract: ... varying Si:N ratios (0.07-1.33). Deep water fertilization led to strongly enhanced primary productivity ... On the one hand, silicification and size of diatom cells remained unaffected by Si:N, which is surprising ... density were strongly reduced and particulate matter C:N was elevated under Si-rich upwelling ...

    Abstract Artificial upwelling has been discussed as a nature-based solution to fertilize currently unproductive areas of the ocean to enhance food web productivity and atmospheric CO2 sequestration. The efficacy of this approach may be closely tied to the nutrient stoichiometry of the upwelled water, as Si-rich water upwelling should benefit the growth of diatoms, who are key players for primary production, carbon export and food web efficiency. With a mesocosm experiment in subtropical waters, we assessed the physiological and functional responses of an oligotrophic phytoplankton community to artificial upwelling under varying Si:N ratios (0.07-1.33). Deep water fertilization led to strongly enhanced primary productivity rates and net autotrophy across Si scenarios. At the community level, Si-rich upwelling temporarily increased primary production and consistently enhanced diatom growth, producing up to 10-fold higher abundances compared to Si-deficient upwelling. At the organism level, contrasting effects were observed. On the one hand, silicification and size of diatom cells remained unaffected by Si:N, which is surprising given the direct dependency of these traits on Si. On the other hand, diatom Chlorophyll a density and carbon density were strongly reduced and particulate matter C:N was elevated under Si-rich upwelling. This suggests a reduced nutritional value for higher trophic levels under high Si:N ratios. Despite these strong qualitative changes under high Si, diatom cells appeared healthy and showed high photosynthetic efficiency. Our findings reveal great physiological plasticity and adaptability in phytoplankton under artificial upwelling, with Si-dependent trade-offs between primary producer quantity and quality.
    Subject code 551
    Language English
    Publishing date 2024-01-04
    Publisher Frontiers
    Publishing country de
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  6. Article ; Online: Phytoplankton physiology and functional traits under artificial upwelling with varying Si:N

    Joaquin Ortiz / Javier Arístegui / Silvan Urs Goldenberg / Mar Fernández-Méndez / Jan Taucher / Stephen D. Archer / Moritz Baumann / Ulf Riebesell

    Frontiers in Marine Science, Vol

    2024  Volume 10

    Abstract: ... varying Si:N ratios (0.07-1.33).ResultsDeep water fertilization led to strongly enhanced ... observed. On the one hand, silicification and size of diatom cells remained unaffected by Si:N, which is ... and carbon density were strongly reduced and particulate matter C:N was elevated under Si-rich ...

    Abstract IntroductionArtificial upwelling has been discussed as a nature-based solution to fertilize currently unproductive areas of the ocean to enhance food web productivity and atmospheric CO2 sequestration. The efficacy of this approach may be closely tied to the nutrient stoichiometry of the upwelled water, as Si-rich upwelling should benefit the growth of diatoms, who are key players for primary production, carbon export and food web efficiency.MethodsWith a mesocosm experiment in subtropical waters, we assessed the physiological and functional responses of an oligotrophic phytoplankton community to artificial upwelling under varying Si:N ratios (0.07-1.33).ResultsDeep water fertilization led to strongly enhanced primary productivity rates and net autotrophy across Si scenarios. At the community level, Si-rich upwelling50 temporarily increased primary production and consistently enhanced diatom growth, producing up to 10-fold higher abundances compared to Si-deficient upwelling. At the organism level, contrasting effects were observed. On the one hand, silicification and size of diatom cells remained unaffected by Si:N, which is surprising given the direct dependency of these traits on Si. On the other hand, diatom Chlorophyll a density and carbon density were strongly reduced and particulate matter C:N was elevated under Si-rich upwelling.DiscussionThis suggests a reduced nutritional value for higher trophic levels under high Si:N ratios. Despite these strong qualitative changes under high Si, diatom cells appeared healthy and showed high photosynthetic efficiency. Our findings reveal great physiological plasticity and adaptability in phytoplankton under artificial upwelling, with Si-dependent trade-offs between primary producer quantity and quality.
    Keywords primary production ; net community production ; phytoplankton ; stoichiometry ; trophic transfer ; carbon export ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Subject code 551
    Language English
    Publishing date 2024-01-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  7. Article: Unsaturated four-membered N-heterocycles: From synthesis to applications

    Didier, Dorian / Andreas N. Baumann / Michael Eisold

    Tetrahedron letters. 2018 Nov. 07, v. 59, no. 45

    2018  

    Abstract: ... as such scaffold can be used to modulate the properties of drug candidates. Unsaturated N-containing four-membered ...

    Abstract The ubiquity of strained motifs in drug discovery has recently witnessed a large regain of interest, as such scaffold can be used to modulate the properties of drug candidates. Unsaturated N-containing four-membered heterocycles present unique opportunities to access functionalized azetidines, which play an essential role in pharmacological studies. Even though those unsaturated patterns have been much less reported than the corresponding saturated versions, the consequent impact that those structures could have on molecular design with implementation of strained modules deserves to be summarized. In this review, synthetic accesses to substituted azetes, 1-azetines and 2-azetines are depicted, as well as their involvement in further transformations.
    Keywords chemical reactions ; chemical structure ; drugs ; heterocyclic nitrogen compounds
    Language English
    Dates of publication 2018-1107
    Size p. 3975-3987.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 204287-3
    ISSN 1873-3581 ; 0040-4039
    ISSN (online) 1873-3581
    ISSN 0040-4039
    DOI 10.1016/j.tetlet.2018.09.055
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  8. Article ; Online: N-terminal domain of ARF-GEF GNOM prevents heterodimerization with functionally divergent GNL1 in Arabidopsis.

    Brumm, Sabine / Singh, Manoj K / Kriechbaum, Choy / Richter, Sandra / Huhn, Kerstin / Kucera, Tim / Baumann, Sarah / Wolters, Hanno / Takada, Shinobu / Jürgens, Gerd

    The Plant journal : for cell and molecular biology

    2022  Volume 112, Issue 3, Page(s) 772–785

    Abstract: ... prevention, we analyzed interactions of the N-terminal dimerization and cyclophilin-binding (DCB) domain ...

    Abstract Evolutionary change following gene duplication can lead to functionally divergent paralogous proteins. If comprising identical subunits their random assortment would also form potentially detrimental heteromeric proteins. In Arabidopsis, the ARF GTPase guanine-nucleotide exchange factor GNOM is essential for polar recycling of auxin-efflux transporter PIN1 from endosomes to the basal plasma membrane whereas its paralog GNL1 mediates retrograde Golgi-endoplasmic reticulum traffic. Here we show that both GNOM and GNL1 form homodimers but no heterodimers. To assess the biological significance of this, we generated transgenic plants expressing engineered heterodimer-compatible GNOM variants. Those plants showed developmental defects such as the failure to produce lateral roots. To identify mechanisms underlying heterodimer prevention, we analyzed interactions of the N-terminal dimerization and cyclophilin-binding (DCB) domain. Each DCB domain interacted with the complementary fragment (ΔDCB) both of their own and of the paralogous protein. However, only DCB
    MeSH term(s) Arabidopsis/genetics ; Arabidopsis/metabolism ; Arabidopsis Proteins/genetics ; Arabidopsis Proteins/metabolism ; Dimerization ; Guanine Nucleotide Exchange Factors/genetics ; Guanine Nucleotide Exchange Factors/metabolism ; Golgi Apparatus/metabolism ; Peptidylprolyl Isomerase/metabolism
    Chemical Substances Arabidopsis Proteins ; Guanine Nucleotide Exchange Factors ; Peptidylprolyl Isomerase (EC 5.2.1.8) ; GNOM protein, Arabidopsis
    Language English
    Publishing date 2022-10-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1088037-9
    ISSN 1365-313X ; 0960-7412
    ISSN (online) 1365-313X
    ISSN 0960-7412
    DOI 10.1111/tpj.15979
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  9. Article ; Online: Nutrient composition (Si:N) as driver of plankton communities during artificial upwelling

    Goldenberg, Silvan U. / Taucher, Jan / Fernandez-Méndez, Mar / Ludwig, Andrea / Aristegui, Javier / Baumann, Moritz / Ortiz Cortes, Joaquin / Stuhr, Annegret / Riebesell, Ulf

    2022  

    Abstract: ... to nitrogen (N). Yet, little is known about how such differences in nutrient composition may influence ... in the subtropical North Atlantic, we tested the biological response to artificial upwelling with varying Si:N ratios ... rich upwelling, leading to C:N ratios as high as 17, well beyond Redfield. Si-rich upwelling also ...

    Abstract Artificial upwelling brings nutrient-rich deep water to the sun-lit surface to boost fisheries or carbon sequestration. Deep water sources under consideration range widely in inorganic silicon (Si) relative to nitrogen (N). Yet, little is known about how such differences in nutrient composition may influence the effectiveness of the fertilization. Si is essential primarily for diatoms that may increase food web and export efficiency via their large size and ballasting mineral shells, respectively. With a month-long mesocosm study in the subtropical North Atlantic, we tested the biological response to artificial upwelling with varying Si:N ratios (0.07-1.33). Community biomass increased 10-fold across all mesocosms, indicating that basic bloom dynamics were upheld despite the wide range in nutrient composition. Key properties of these blooms, however, were influenced by Si. Photosynthetic capacity and nutrient-use efficiency doubled from Si-poor to Si-rich upwelling, leading to C:N ratios as high as 17, well beyond Redfield. Si-rich upwelling also resulted in 6-fold higher diatom abundance and mineralized Si and a corresponding shift from smaller towards larger phytoplankton. The pronounced change in both plankton quantity (biomass) and quality (C:N ratio, size and mineral ballast) for trophic transfer and export underlines the pivotal role of Si in shaping the response of oligotrophic regions to upwelled nutrients. Our findings indicate a benefit of active Si management during artificial upwelling with the potential to optimize fisheries production and CO2 removal.
    Subject code 551 ; 550
    Language English
    Publishing date 2022-11-25
    Publisher Frontiers
    Publishing country de
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  10. Article ; Online: Counteracting effects of nutrient composition (Si:N) on export flux under artificial upwelling

    Moritz Baumann / Silvan Urs Goldenberg / Jan Taucher / Mar Fernández-Méndez / Joaquin Ortiz / Jacqueline Haussmann / Ulf Riebesell

    Frontiers in Marine Science, Vol

    2023  Volume 10

    Abstract: ... In a mesocosm experiment, we tested the effect of nutrient composition (Si relative to N) in artificially ... to a doubling of exported particulate matter and increased C:N ratios to well beyond Redfield (9.5 to 11.1 ... increase in POC export and ~30% increase in C:N ratios compared to Si-scarce upwelling. Whilst the biogenic ...

    Abstract To keep global warming below 1.5°C, technologies that remove carbon from the atmosphere will be needed. Ocean artificial upwelling of nutrient-rich water stimulates primary productivity and could enhance the biological carbon pump for natural CO2 removal. Its potential may depend on the Si availability in the upwelled water, which regulates the abundance of diatoms that are key carbon exporters. In a mesocosm experiment, we tested the effect of nutrient composition (Si relative to N) in artificially upwelled waters on export quantity and quality in a subtropical oligotrophic environment. Upwelling led to a doubling of exported particulate matter and increased C:N ratios to well beyond Redfield (9.5 to 11.1). High Si availability stimulated this carbon over-consumption further, resulting in a temporary ~5-fold increase in POC export and ~30% increase in C:N ratios compared to Si-scarce upwelling. Whilst the biogenic Si ballast of the export flux increased more than 3.5-fold over the Si:N gradient, these heavier particles did not sink faster. On the contrary, sinking velocity decreased considerably under high Si:N, most likely due to reduced particle size. Respiration rates remained similar across all treatments indicating that biogenic Si did not protect particles against microbial degradation. Si availability thus influenced key processes of the biological carbon pump in counteracting ways by increasing the export magnitude and associated C:N ratios but decreasing the efficiency of carbon transfer to depth. These opposing effects need to be considered when evaluating the potential of artificial upwelling as negative emission technology.
    Keywords artificial upwelling ; biological carbon pump ; particulate matter export ; sinking velocity ; remineralization rate ; carbon sequestration ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Subject code 550
    Language English
    Publishing date 2023-07-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

To top