Precursores colinérgicos comparados: alfa-GPC y citicolina en la literatura

Human plasma after oral citicoline carries uridine, not cytidine, which is the reverse of the rat. The two cholinergic precursors reach the same cycle by different chemistry.
Modulación de los receptores AMPA: qué hacen las ampakinas a nivel molecular

A 2002 structure of GluR2 showed that stabilising the dimer interface reduces desensitisation. Everything ampakines are said to do at the molecular level follows from that one interface.
The Racetams and Their Missing Mechanism: Fifty Years Without a Consensus

A 1994 review of 407 papers reported no accepted mechanism for the racetams. A 2010 review still called it an enigma, and the crystal structures published in between separated the class rather than unifying it.
El modafinilo y el transportador de dopamina: lo que mostraron los estudios de imagen

A 1994 paper reported low-affinity binding at the dopamine uptake site; PET imaging in 2009 put human transporter occupancy between 39 and 54 percent. The mechanism debate did not end there.
El doble perfil de Bromantane: la investigación sobre actoprotectores de la era soviética

Forty-five of the fifty-six PubMed records naming this compound in the title carry no DOI, and six carry no abstract at all. The evidence base is measurable before it is readable.
La base de evidencia de los compuestos de investigación cognitiva: una guía crítica

A molecule can be active in a cell-free assay, produce a clean result in mice, and show nothing in a randomised trial without any contradiction. This hub maps the evidence hierarchy and the failure modes at each level.