We report that the dimeric alkaloid stephacidin B () and the monomeric alkaloid avrainvillamide () function equivalently within experimental error to inhibit the growth of four different cultured human cancer cell lines. We also show that the proportion of the monomer greatly outweighs that of the dimer in the medium of incubation, and that the half-life for the transformation of to is short relative to the half-life of cell division. Finally, using a monomer-based affinity reagent, we provide evidence that the monomer () interacts with intracellular thiol-containing proteins, likely by covalent modification.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3175819 | PMC |
http://dx.doi.org/10.1021/ja0690971 | DOI Listing |
Oecologia
January 2025
Plant Evolutionary Ecology, Institute of Ecology, Evolution and Diversity, Faculty of Biological Sciences, Goethe University Frankfurt, Max-Von-Laue-Str. 13, 60438, Frankfurt am Main, Germany.
Rapid environmental changes across Europe include warmer and increasingly variable temperatures, changes in soil nutrient availability, and pollinator decline. These abiotic and biotic changes can affect natural plant populations and force them to optimize resource use against competitors. To date, the evolution of competitive ability in the context of changes in nutrient availability remains understudied.
View Article and Find Full Text PDFEpilepsia
January 2025
Epilepsy Unit, Hôpital Gui de Chauliac, Montpellier, France.
Contemporary studies report nonconvulsive status epilepticus (NCSE) in Creutzfeldt-Jakob disease (CJD), based on benzodiazepine (BZP)-responsive epileptiform discharges on the electroencephalogram (EEG), with the following false syllogism: (1) intravenous (IV) administration of BZPs usually suppress ictal activity in NCSE; (2) in CJD, periodic sharp wave complexes (PSWCs) are suppressed by IV BZPs; (3) therefore, these patients have NCSE. This is a simplistic and invalid conclusion, because authors of 20th-century science reports have clearly shown that IV BZPs, short-acting barbiturates, and drugs with no antiseizure effects, such as chloral hydrate and IV naloxone, suppress PSWCs, but patients fall asleep with no clinical improvement. In contrast, IV methylphenidate transiently improves both the EEG and clinical states.
View Article and Find Full Text PDFHarm Reduct J
January 2025
Finnish Institute for Health and Welfare, Mannerheimintie 166, 00271, Helsinki, Finland.
Background: Taxation can be used to direct consumption and provision of harmful commodities. Prior research on gambling taxation has nevertheless been inconclusive on whether this can also apply to gambling. In gambling policy, optimal taxation rates have particularly been debated from the perspective of channelling consumption from offshore markets to regulated markets.
View Article and Find Full Text PDFNat Commun
January 2025
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu, China.
The boundary between wet and arid climate zones in the Tethys Ocean remains challenging to trace, complicating our understanding of global aridification pattern during the Late Carboniferous to Early Permian transition. The North China Block (NCB), situated in the Tethys Ocean, underwent a transition from humid to arid climate during the Early Permian, providing a rare opportunity to trace this climate boundary across this region. Here, we present paleomagnetic evidence indicating that the NCB underwent rapid northward drift between 290 and 281 million years ago.
View Article and Find Full Text PDFJ Med Internet Res
January 2025
Ophthalmology Department, First Affiliated Hospital of GuangXi Medical University, Nanning, China.
Background: In recent years, with the rapid development of machine learning (ML), it has gained widespread attention from researchers in clinical practice. ML models appear to demonstrate promising accuracy in the diagnosis of complex diseases, as well as in predicting disease progression and prognosis. Some studies have applied it to ophthalmology, primarily for the diagnosis of pathologic myopia and high myopia-associated glaucoma, as well as for predicting the progression of high myopia.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!