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- PublicationOpen AccessLa piel como lienzo: color y género en el tatuaje dentro de la cultura Custom(Universidad Complutense de Madrid, 2025) José Mayor Iborra; García López, Antonio; Mayor Iborra, José; Fernández Quesada, Blanca ; Bellas Artes; Bellas Artes; Blanca Fernández Quesada; Facultad de Bellas ArtesEl estudio aborda el papel del color en el tatuaje dentro del universo visual de la cultura custom y biker, entendiendo la piel como soporte activo de construcción simbólica. A partir de un análisis iconográfico de motivos recurrentes, especialmente la figura pin-up, se examina cómo el cromatismo interviene en la configuración de identidades y en la circulación de imaginarios de género. Desde los estudios de cultura visual y perspectiva feminista, se plantea que el tatuaje constituye un espacio de negociación estética donde conviven herencias visuales patriarcales y procesos contemporáneos de reapropiación corporal.
- PublicationOpen AccessPrognostic relevance of cholinergic signaling changes in head and neck squamous cell carcinomas(2014) Nieto Cerón, Susana; Bioquímica y Biología Molecular B e InmunologíaThe traditional view of acetylcholine (ACh) acting solely as neurotransmitter has changed based on the findings demonstrating that non-neuronal cholinergic system is vital for various types of cells such as epithelial, endothelial and immune cells. Changes in the expression of ACh-linked genes were causally related with cell proliferation. So, excess of ACh is expected to exacerbate cholinergic inputs and by this means accelerate tumour growth. This research was addressed to explore a possible link of cholinergic signalling changes with head and neck cancer. For this, paired pieces of head and neck squamous cell carcinoma (HNSCC) and adjacent non-cancerous tissue (ANCT) were compared for their mRNA levels for ACh-related proteins and AChhydrolyzing activity. The measurement in ANCT of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities (5.416 ± 0.501 mU/mg protein and 6.442 ± 0.595 mU/mg protein) demonstrated that upper respiratory tract is capable of controlling the availability of ACh. In HNSCC, AChE and BChE activities dropped to 3.584 ± 0.633 mU/mg (p = 0.002) and 4.002 ± 0.418 mU/mg (p = 0.001). Moreover, tumours with AChE activity above 1.801 mU/mg (50th percentile) and BChE activity below 3.061 mU/mg were associated with increased patient overall survival. ANCT and HNSCC differed in mRNA levels for AChE-T and AChE-H, α7 and α5 of nAChR, and M3 and M2 mAChR. Our results suggest that the low AChE activity in HNSCC was associated with poor overall survival. So, the ChE activity level of head and neck carcinoma can be used as a reliable prognostic marker.
- PublicationOpen AccessA new class of aggregation inhibitor of amyloid-beta peptide based on green tea catechins(2014) Nieto Cerón, Susana; Bioquímica y Biología Molecular B e InmunologíaAlzheimer's disease (AD), the major dementing disorder of the elderly which accounts for 55% of all dementia patients worldwide, is related to amyloid-beta peptide, the main component of senile plaques in Alzheimer's disease brain. Observations suggest a broad ability for green tea catechins (GTC) to disrupt early-stage and late-stage aggregation processes but the molecular mechanism has not been fully elucidated. To advance the understanding of the potential use of GTC in the prevention or treatment of AD patients, we investigated the effect of natural and synthetic compounds on APP processing. We checked the ability of gallate containing phenolic compounds, including (-)-catechin, (-)- catechin gallate, (-)-epicatechin gallate, (-)-epigallocatechin, (-)-epigallocatechin gallate, gallic acid, and trimethoxy derivatives of epicatechin-3-gallate to inhibit acetylcholinesterase (AChE) activity and AChE-promoted Aβ aggregation. Compounds were analyzed for their ability to inhibit AChE by colorimetric and radiometric assays and for determining their type of enzyme inhibition. Fluorimetric studies with thioflavin T were performed to evaluate their effect on beta amyloid aggregation. We have found that TMCG, a 3,4,5-trimethoxy derivative of catechin gallate, exhibits a non competitive inhibition of AChE, has a disaggregating effect on amyloid fibrils and decreases the secretion of both 1-40 and 1-42 amyloid peptides to the extracellular medium of SH-SY5Y APP695 cell cultures. According to stability and bioavailability, methoxy derivates of catechins are promising drug to ameliorate the Alzheimer´s pathogenesis.
- PublicationOpen AccessCooperative fluoride binding in (thio)urea [2]rotaxanes: a mechanical-bond approach to phase‐transfer catalysis(2026-07-05) Puigcerver Alarcón, Julio; Zamora Gallego, José María; Marín Luna, Marta; Alajarín Cerón, Mateo; Martínez Cuezva, Alberto; Berná Cánovas, José; Química Orgánica; Facultades de la UMU::Facultad de QuímicaThe distinctive features of mechanically interlocked molecules have been widely recognised for decades.[1] In this context, our research focuses on integrating the unique structural characteristics of rotaxanes with the catalytic potential of specific functional motifs.[2][3] Hydrogen-bond donor groups such as ureas and thioureas have been extensively employed in anion sensing[4] and anion-binding catalysis.[5] Nevertheless, various strategies have been developed to address their intrinsic limitations and enhance their catalytic performance.[6] In this study, we explore the catalytic potential of tetraamide [2]rotaxanes incorporating urea and thiourea moieties as hydrogen-bonding phase-transfer catalysts in nucleophilic fluorination reactions.[7] We hypothesised that the hydrogen-bond-donating nature of the tetralactam macrocycle could strengthen the interaction of these functional groups with fluoride anions. To test this hypothesis, a series of urea-functionalised rotaxanes were designed and evaluated as catalysts. Our results demonstrate that the cooperative activation of fluoride between the macrocycle and the hydrogen-bond donor significantly improves reaction yields compared with non-interlocked thread analogues.[8] Furthermore, we report a clipping strategy employing activated isophthaloyl-derived esters as key precursors for the synthesis of thiourea-containing rotaxanes. This approach overcomes the incompatibility issues encountered when acyl chloride derivatives were used in the presence of highly nucleophilic thiourea groups. The steric constraints imposed by the mechanical bond enable the use of an interlocked thiourea as a hydrogen-bonding phase-transfer catalyst in nucleophilic fluorination, a reaction previously restricted to urea-based systems.[9] Overall, these findings highlight the pivotal role of the mechanical bond in modulating catalytic activity. References [1] C. J. Bruns, J. F. Stoddart. The Nature of the Mechanical Bond: From Molecules to Machines. Wiley, Weinheim, 2016. [2] A. Martinez-Cuezva, A. Saura-Sanmartin, J. Berna, M. Alajarin. ACS Catal. 2020, 10, 7719. [3] M. Calles, J. Puigcerver, D. A. Alonso, M. Alajarin, A. Martinez-Cuezva, J. Berna, Chem. Sci. 2020, 11, 3629. [4] S. Kundu, T. K. Egboluche, M. A. Hossain. Acc. Chem. Res. 2023, 56, 1320. [5] K. Brak, E. N. Jacobsen. Angew. Chem. Int. Ed. 2013, 52, 534. [6] T. J. Auvil, A. G. Schafer, A. E. Mattson. Eur. J. Org. Chem. 2014, 2633. [7] G. Pupo, V. Gouverneur. J. Am. Chem. Soc. 2022, 144, 5200. [8] J. Puigcerver, J. M. Zamora-Gallego, M. Marin-Luna, A. Martinez-Cuezva, J. Berna. J. Am. Chem. Soc. 2024, 146, 22887. [9] J. Puigcerver, J. S. Dato-Santiago, M. Alajarin, A. Martinez-Cuezva, J. Berna. Org. Lett. 2025, 27, 2873.
- PublicationOpen AccessPopulation concentration. Quantitative characterization by concentration indexes(INU Edizione Srl, 2024-06-01) Alvira Baeza, Ricardo; Ciencia Política y de la Administración (en constitución); Facultades de la UMU::Facultad de DerechoEl trabajo analiza el fenómeno de la concentración de la población desde una perspectiva histórica, teórica y cuantitativa. Tras revisar los principales enfoques desarrollados para comprender la distribución territorial de la población, distingue entre las propuestas normativas de organización espacial, representadas por autores como Platón y Ebenezer Howard, y las aproximaciones empírico-estadísticas iniciadas por Auerbach y posteriormente desarrolladas por la teoría de los lugares centrales. A partir de este marco, se plantea la necesidad de superar el análisis basado únicamente en la dicotomía entre población urbana y rural mediante indicadores que permitan medir el grado de concentración territorial. Como aplicación empírica, el estudio examina la evolución de la concentración de la población en España entre 1787 y 2020 utilizando índices de concentración, observando un incremento sostenido del fenómeno paralelo al crecimiento demográfico. El trabajo propone estos indicadores como herramientas para caracterizar y comparar la distribución espacial de la población, analizar su relación con otras variables territoriales y establecer objetivos de redistribución demográfica fundamentados en evidencia cuantitativa. Asimismo, se plantea la utilidad de este enfoque para el diseño y la evaluación de políticas públicas orientadas al equilibrio territorial y al desarrollo urbano sostenible.