Search results for " Plaque"

Los caballos en la Cova del Parpalló (Gandía, Valencia)

2005

Se estudian 165 plaquetas grabadas de la Cova del Parpalló, de las que 115 contienen una o varias representaciones de caballos que siguen las mismas grandes tendencias sugeridas por Villaverde. Es posible, con todo, señalar la existencia de dos subtendencias: por un lado un creciente grosor de los trazos, y por otro la consecución del volumen a través de trazos múltiples y repetidos. La tendencia a desarrollar el volumen está en correlación con el alargamiento del cuello y la representación dinámica del pecho, mediante una línea oblicua proyectada hacia adelante. Nuestra intención es, además, poner de manifiesto las concomitancias que se registran en el Solutro-gravetiense entre los cambios…

Arte mueble de la España mediterránea : Breve síntesis y algunas consideraciones teóricas

1994

En este trabajo se analiza el arte mueble de/Mediterráneo español, basándose especialmente en la colección de plaquetas de El Parpalló. El estudio detallado de los motivos artísticos y su correlación estratigráfica revela algunas diferencias cronológicas en un marco de evolución continua. Conceptos tradicionales, como el de “Provincia Mediterránea‘~ son revisados a la luz de nuevos enfoques teóricosy empíricos. Portable art of Mediterranean Spain is analyzed in this paper with special reference (o the more than five thousand decoratedplaquettesfrom El Parpalló. A detailed study of artistic mot¡fs and stratigraphy reveals some chronological differences inside a frame of continous evolution. …

Immunohistochemical investigation of the brain of aged dogs. I. Detection of neurofibrillary tangles and of 4-hydroxynonenal protein, an oxidative da…

2001

In the aging dog brain lesions develop spontaneously. They share some morphological characteristics with those of Alzheimer 's disease in man. Diffuse and primitive plaques are well known, whereas neuritic plaques rarely develop. Neurofibrillary tangles have not been seen in the canine. The aim of the present investigation was to study major age-related changes of the dog's brain using paraffin sections with respect to cross-immunoreactivity of tau, A beta protein and other immunoreactive components including hydroxynonenal protein, which is a marker for oxidative damage. The occurrence of neurofibrillary tangles and of the protein tau therein was studied in serial brain sections of two dog…

Molecular mechanisms linking amyloid β toxicity and Tau hyperphosphorylation in Alzheimer׳s disease

2015

Neurofibrillary tangles (aggregates of cytoskeletal Tau protein) and senile plaques (aggregates mainly formed by amyloid β peptide) are two landmark lesions in Alzheimer׳s disease. Some researchers have proposed tangles, whereas others have proposed plaques, as primary lesions. For a long time, these were thought of as independent mechanisms. However, experimental evidence suggests that both lesions are intimately related. We review here some molecular pathways linking amyloid β and Tau toxicities involving, among others, glycogen synthase kinase 3β, p38, Pin1, cyclin-dependent kinase 5, and regulator of calcineurin 1. Understanding amyloid β and Tau toxicities as part of a common pathophys…

Protection of Flupirtine on β-Amyloid-Induced Apoptosis in Neuronal Cells In Vitro: Prevention of Amyloid-Induced Glutathione Depletion

2002

Effective drugs are not available to protect against beta-amyloid peptide (A beta)-induced neurotoxicity. Cortical neurons from rat embryos were treated with the toxic fragment A beta25-35 at 1 microM in the presence or absence of flupirtine, a triaminopyridine, successfully applied clinically as a nonopiate analgesic drug. Five days later 1 microM A beta25-35 caused reduction of cell viability to 31.1%. Preincubation of cells with flupirtine (1 or 5 microg/ml) resulted in a significant increase of the percentage of viable cells (74.6 and 65.4%, respectively). During incubation with A beta25-35 the neurons undergo apoptosis as determined by appearance of the characteristic stepladder-like D…

Abnormal accumulation of autophagic vesicles correlates with axonal and synaptic pathology in young Alzheimer's mice hippocampus

2012

Dystrophic neurites associated with amyloid plaques precede neuronal death and manifest early in Alzheimer's disease (AD). In this work we have characterized the plaque-associated neuritic pathology in the hippocampus of young (4- to 6-month-old) PS1(M146L)/APP(751SL) mice model, as the initial degenerative process underlying functional disturbance prior to neuronal loss. Neuritic plaques accounted for almost all fibrillar deposits and an axonal origin of the dystrophies was demonstrated. The early induction of autophagy pathology was evidenced by increased protein levels of the autophagosome marker LC3 that was localized in the axonal dystrophies, and by electron microscopic identification…

Alzheimer's disease: Amyloid deposits in the cerebellar cortex

1989

Heterocyclic Scaffolds for the Treatment of Alzheimer's Disease

2016

Background: The treatment and diagnosis of Alzheimer’s Disease (AD) are two of the most urgent goals for research around the world. The cognitive decline is generally associated with the elevated levels of extracellular senile plaques, intracellular neurofibril- lary tangles (NFTs), and with a progressive shutdown of the cholinergic basal forebrain neurons transmission. Even if several key targets are under fervent investigation in the cure of AD, till now, the only approved therapeutic strategy is the treatment of symptoms by using cholinesterases inhibitors. It has been demonstrated that both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes are not only responsible of…

Oral hygiene and periodontal health status among khat chewers. A case-control study

2016

Background Habitual khat chewing is a widespread male habit in Southern Arabia and East Africa. The aim of this study was to assess the effect of Khat chewing on oral hygiene and periodontal health status among Yemeni male khat chewers. Material and Methods This case- control study included 310 khat chewers, aged 20-65 years, and 72 age- and gender- matched non-chewers as controls. Periodontal examination included recording of dental plaque index (PI), gingival index (GI), probing pocket depth (PPD), attachment level (AL) and gingival recession (GR). Demographic data, oral hygiene practices, and duration, frequency and site of khat chewing were obtained using questionnaires. SPSS was used f…

Periopathogenic bacteria in dental plaque of Congolese patients with periodontitis : a pilot study

2018

Background Periopathogenic bacteria play an important role in the etiology of periodontal disease. At present, no study screening for periopathogens in the DR Congo was carried out. The aim of this pilot study was to investigate the prevalence of five periopathogens in Congolese patients with periodontitis and to determine the association between these bacteria. Material and Methods Twelve patients (eight women and four men) with a mean age of 45 ± 19 years from those consulted in dental services of two medical centers of Kinshasa from April 2017 to October 2017 were included. Full mouth examination was registered, the probing pocket depth and clinical attachment level were assessed at six …