327 resultados para Malaltia de Creutzfeldt-Jakob
Resumo:
Amyloid aggregation is linked to a large number of human disorders, from neurodegenerative diseases as Alzheimer"s disease (AD) or spongiform encephalopathies to non-neuropathic localized diseases as type II diabetes and cataracts. Because the formation of insoluble inclusion bodies (IBs) during recombinant protein production in bacteria has been recently shown to share mechanistic features with amyloid self-assembly, bacteria have emerged as a tool to study amyloid aggregation. Herein we present a fast, simple, inexpensive and quantitative method for the screening of potential anti-aggregating drugs. This method is based on monitoring the changes in the binding of thioflavin-S to intracellular IBs in intact Eschericchia coli cells in the presence of small chemical compounds. This in vivo technique fairly recapitulates previous in vitro data. Here we mainly use the Alzheimer"s related beta-amyloid peptide as a model system, but the technique can be easily implemented for screening inhibitors relevant for other conformational diseases simply by changing the recombinant amyloid protein target. Indeed, we show that this methodology can be also applied to the evaluation of inhibitors of the aggregation of tau protein, another amyloidogenic protein with a key role in AD.
Resumo:
A series of 1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridines differently substituted at positions 1, 5, and 9 have been designed from the pyrano[3,2-c]quinoline derivative 1, a weak inhibitor of acetylcholinesterase (AChE) with predicted ability to bind to the AChE peripheral anionic site (PAS), at the entrance of the catalytic gorge. Fourteen novel benzonaphthyridines have been synthesized through synthetic sequences involving as the key step a multicomponent Povarov reaction between an aldehyde, an aniline and an enamine or an enamide as the activated alkene. The novel compounds have been tested against Electrophorus electricus AChE (EeAChE), human recombinant AChE (hAChE), and human serum butyrylcholinesterase (hBChE), and their brain penetration has been assessed using the PAMPA-BBB assay. Also, the mechanism of AChE inhibition of the most potent compounds has been thoroughly studied by kinetic studies, a propidium displacement assay, and molecular modelling. We have found that a seemingly small structural change such as a double O → NH bioisosteric replacement from the hit 1 to 16a results in a dramatic increase of EeAChE and hAChE inhibitory activities (>217- and >154-fold, respectively), and in a notable increase in hBChE inhibitory activity (> 11-fold), as well. An optimized binding at the PAS besides additional interactions with AChE midgorge residues seem to account for the high hAChE inhibitory potency of 16a (IC50 = 65 nM), which emerges as an interesting anti-Alzheimer lead compound with potent dual AChE and BChE inhibitory activities.
Resumo:
We have synthesized a family of rhein-huprine hybrids to hit several key targets for Alzheimer"s disease. Biological screening performed in vitro and in Escherichia coli cells has shown that these hybrids exhibit potent inhibitory activities against human acetylcholinesterase butyrylcholinesterase, and BACE-1, dual Aβ42 and tau anti-aggregating activity, and brain permeability. Ex vivo studies with the leads (+)- and (-)-7e in brain slices of C57bl6 mice have revealed that they efficiently protect against the Aβ-induced synaptic dysfunction , preventing the loss of synaptic proteins and/or have a positive effect on the induction of long term potentiation. In vivo studies in APP-PS1 transgenic mice treated i.p. for 4 weeks with (+)- and (-)-7e have shown a central soluble Aβ lowering effect, accompanied by an increase in the levels of mature amyloid precursor protein (APP). Thus, (+)- and (-)-7e emerge as very promising disease-modifying anti-Alzheimer drug candidates.
Resumo:
Multitarget compounds are increasingly being pursued for the effective treatment of complex diseases. Herein, we describe the design and synthesis of a novel class of shogaolhuprine hybrids, purported to hit several key targets involved in Alzheimer"s disease. The hybrids have been tested in vitro for their inhibitory activity against human acetylcholinesterase and butyrylcholinesterase and antioxidant activity (ABTS.+, DPPH and Folin-Ciocalteu assays), and in intact Escherichia coli cells for their Aβ42 and tau anti-aggregating activity. Also, their brain penetration has been assessed (PAMPA-BBB assay). Even though the hybrids are not as potent AChE inhibitors or antioxidant agents as the parent huprine Y and [4]-shogaol, respectively, they still exhibit very potent anticholinesterase and antioxidant activities and are much more potent Aβ42 and tau anti-aggregating agents than the parent compounds. Overall, the shogaolhuprine hybrids emerge as interesting brain permeable multitarget anti-Alzheimer leads.
Resumo:
We describe the multigram synthesis and in vivo efficacy studies of a donepezil‒huprine hybrid that has been found to display a promising in vitro multitarget profile of interest for the treatment of Alzheimer's disease (AD). Its synthesis features as the key step a novel multigram preparative chromatographic resolution of intermediate racemic huprine Y by chiral HPLC. Administration of this compound to transgenic CL4176 and CL2006 Caenorhabditis elegans strains expressing human Aβ42, here used as simplified animal models of AD, led to a significant protection from the toxicity induced by Aβ42. However, this protective effect was not accompanied, in CL2006 worms, by a reduction of amyloid deposits. Oral administration for 3 months to transgenic APPSL mice, a well-established animal model of AD, improved short-term memory, but did not alter brain levels of Aβ peptides nor cortical and hippocampal amyloid plaque load. Despite the clear protective and cognitive effects of AVCRI104P4, the lack of Aβ lowering effect in vivo might be related to its lower in vitro potency toward Aβ aggregation and formation as compared with its higher anticholinesterase activities. Further lead optimization in this series should thus focus on improving the anti-amyloid/anticholinesterase activity ratio.
Resumo:
Aquest treball es basa en les pràctiques realitzades dins del marc del Màster en Envelliment Actiu de la Universitat de Vic. L’objectiu d’aquestes pràctiques era doble: per una banda, aprofundir en el coneixement del rol del psicogerontòleg en un centre sociosanitari d’atenció a la gent gran i, per l’altra, elaborar, aplicar i avaluar una intervenció per fomentar l’envelliment actiu. És a dir, es pretenia donar cobertura a les dues grans àrees d’intervenció a les quals ha de fer front el psicogerontòleg en l’actualitat, com veurem més endavant, i que són: l’atenció a la dependència i la promoció de l’envelliment actiu, tenint en compte que aquesta darrera suposa la prevenció de la malaltia i la discapacitat i la maximització del benestar i la qualitat de vida en la vellesa.
Resumo:
OBJECTIU: determinar la qualitat de vida de les persones amb demència ateses en una unitat avaluadora de deteriorament cognitiu. MÈTODE: estudi descriptiu transversal amb una mostra consecutiva no probabilística, formada per 42 persones amb demència tipus Alzheimer lleu o moderada i els seus cuidadors. La Qualitat de Vida (QV) es va avaluar amb el qüestionari QoL-AD (Quality of Life Alzheimer’s Disease) en les versions per al pacient (QoL-ADp) i per al cuidador (QoL-ADc). RESULTATS: la mitjana de puntuació del QoL-ADp va ser de 35,38 punts (DE = 5,24) i del QoL-Adc, de 30,60 (DE 5,33). La diferència entre aquests resultats és significativa (p<0,001). Els pacients amb simptomatologia depressiva i els seus cuidadors van puntuar significativament més baix el QoL-AD (p<0,001). En les freqüències per ítems del QoL-ADp s’observa que: més del 75% van valorar com a bona/excel·lent les condicions de vida, família, matrimoni/relació estreta, vida social, situació financera i vida en general; el 61% valoraren bona/excel·lent la capacitat per realitzar tasques a casa; prop del 50% pensava que l’estat d’ànim, l’energia, la salut física, la capacitat per fer coses per diversió i la visió de si mateixos era dolenta/regular, i el 85,7% opinava que la seva memòria era dolenta/regular. CONCLUSIONS: els resultats obtinguts en el QoL-AD no difereixen dels obtinguts en altres investigacions. Suggereixen que les intervencions que genera l’avaluació de la QV en la pràctica clínica inclouen aspectes centrats pròpiament en la malaltia i aspectes vinculats amb les relacions socials.
Resumo:
Malgrat els falsos profetes apocalíptics,que darrere els seus auguris de frac- tura social només amaguen obscurs anhels partidistes que es produeixin, el cert és que vivim un bon moment pel que fa a l'assumpció i integració de les diferències, incloses les mal anomenades minusvalideses. A poc a poc es van eliminant les barreres arquitectòniques que dificulten la vida social de les persones amb mobilitat reduïda, i augmenta la conscienciació social per eliminar els comportaments incívics, com ara aparcar davant els passos de vianants [...].
Resumo:
Un dels objectius centrals en biomedicina és la cerca de noves teràpies. Hi ha moltes aproximacions possibles, depenent de la malaltia i la tecnologia disponible, des de les més expeditives, com la cirurgia, fins a les més sofisticades, basades en l'enginyeria genètica, passant pels medicaments convencionals,que aprofiten els efectes de determinats productes sobre el nostre cos. En qualsevol cas, cada cop que s'utilitza una nova estratègia terapèutica o es comercialitza un nou fàrmac hi ha la possibilitat que es produeixin efectes secundaris inesperats [...].
Resumo:
El tromboembolisme pulmonar és una malaltia greu que presenta una elevada morbimortalitat. Sol ser una complicació de la trombosi venosa profunda, i tots dos desordres formen part d’una mateixa malaltia anomenada tromboembolisme venós.Els pacients ingressats a la unitat de cures intensives tenen un elevat risc de patirtromboembolisme venós. La forma de presentació clínica del tromboembolismepulmonar és molt variable, cosa que dificulta i retarda el diagnòstic. Per aquests motius, una adequada prevenció de la malaltia és fonamental per reduir-ne la incidència i la mortalitat Objectiu: Descriure les cures que poden realitzar els professionals d'infermeria perprevenir el tromboembolisme pulmonar en els malalts críticsConclusions: Les cures que poden realitzar els professionals d’infermeria per laprevenció del tromboembolisme pulmonar són l’administració d’anticoagulants,col·locació de dispositius mecànics i mobilització precoç. Quan estigui indicat, el metgepot col·locar filtres de la vena cava inferior. També és important tenir coneixementsactuals i avaluar l’estat del pacient. Cal més investigació, sobretot d’infermeria, per trobar nous mètodes preventius més efectius i segurs
Resumo:
Metabotropic glutamate (mGlu) receptors are G protein-coupled receptors expressed primarily on neurons and glial cells modulating the effects of glutamatergic neurotransmission. The pharmacological manipulation of these receptors has been postulated to be valuable in the management of some neurological disorders. Accordingly, the targeting of mGlu5 receptors as a therapeutic approach for Parkinson's disease (PD) has been proposed, especially to manage the adverse symptoms associated to chronic treatment with classical PD drugs. Thus, the specific pharmacological blocking of mGlu5 receptors constitutes one of the most attractive non-dopaminergic-based strategies for PD management in general and for the L-DOPA-induced diskynesia (LID) in particular. Overall, we provide here an update of the current state of the art of these mGlu5 receptor-based approaches that are under clinical study as agents devoted to alleviate PD symptoms.