Search results for "Rivas"
showing 10 items of 37 documents
Parasitismo intestinal en población infantil de los departamentos del Pacífico Nicaragüense
2014
Formando parte de los estudios encaminados al conocimiento del parasitismo intestinal en la población infantil nicaragüense, la presente Tesis Doctoral tiene como objetivo básico abordar el parasitismo intestinal en los diferentes Departamentos que conforman la Región Pacífico, excepción hecha del Departamento de Managua. Para ello se ha estudiado coproparasitológicamente un total de 1881 sujetos (939 niños y 942 niñas), de edades comprendidas entre 0 y 15 años, procedentes de los Departamentos de Chinandega, León, Masaya, Carazo, Granada y Rivas. El espectro enteroparasitario ha quedado conformado por un mínimo de 20 especies (13 de protozoos y 7 especies de helmintos). Desde el punto de v…
Smēķēšanas un perivaskulāro taukaudu savstarpējā mijiedarbība asinsvadu veselībā
2021
Darba mērķis bija novērtēt cigarešu smēķēšanas un perivaskulāro taukaudu ietekmi uz kopējās miega artērijas sieniņas IMT. Pētījumā piedalījās 9 personas vecuma 18-25 gadiem ar atšķirīgu smēķēšanas statusu. Veica antropometriskos mērus ķermeņa svara raksturojumam; ar ultrasonogrāfiju noteica PVAT daudzumu, mērot kopējās miega artērijas EMT; kā arī IMT, ko izmanto aterosklerozes agrīnā diagnosticēšanā. Nelielā pētījuma dalībnieku skaita dēļ, rezultāti tika salīdzināti ar citu zinātnisko pētījumu datiem, kas iegūti ar līdzīgām metodēm. No literatūras analīzes izriet, ka PVAT akumulācija var rosināt artēriju sieniņu sabiezināšanos, savukārt smēķēšana mijiedarbojas ar endotēlija funkciju. Smēķēt…
Assessment of Susceptibility Risk Factors for ADHD in Imaging Genetic Studies
2019
Objective: ADHD consists of a count of symptoms that often presents heterogeneity due to overdispersion and excess of zeros. Statistical inference is usually based on a dichotomous outcome that is underpowered. The main goal of this study was to determine a suited probability distribution to analyze ADHD symptoms in Imaging Genetic studies. Method: We used two independent population samples of children to evaluate the consistency of the standard probability distributions based on count data for describing ADHD symptoms. Results: We showed that the zero-inflated negative binomial (ZINB) distribution provided the best power for modeling ADHD symptoms. ZINB reveals a genetic variant, rs273342…
Vascular damage and lack of angiogenesis in systemic sclerosis skin
2003
The aim of this study was to analyse microvascular damage and compensatory angiogenesis in skin from patients with systemic sclerosis (SSc) compared with systemic lupus erythematosus (SLE), Raynaud's phenomenon (RP) and healthy controls. Immunohistochemistry was used for skin biopsies (9 SSc, 10 SLE, 9 RP and 12 healthy controls) using von Willebrand factor and beta3 integrin subunit specific antibodies, TechMate immunostaining robot and biotin-streptavidin protocol. In the early stages of SSc, vWF was found in the perivascular space and interstitial matrix in papillary but not in the reticular dermis, in particular around small oedematous blood vessels infiltrated by mononuclear cells. The…
Effect of cholinergic stimulation in early Alzheimer's disease - functional imaging during a recognition memory task.
2011
Treatment of Alzheimer's disease (AD) with acetylcholinesterase inhibitors (AChEI) enhances cholinergic activity and alleviates clinical symptoms. In the present functional magnetic resonance imaging (fMRI) study, we investigated the effect of the AChEI rivastigmine on cognitive function and brain activation patterns during a face recognition memory task. Twenty patients with newly-diagnosed mild AD were administered a single oral dose of placebo, a single dose of rivastigmine (acute), and twice-daily treatment with rivastigmine for 4 weeks (chronic). After each treatment, the patients underwent a facial recognition task during fMRI. The prefrontal areas known to be involved in face recogni…
Effects of cerivastatin on adrenergic pathways, hypertrophic growth and TGFbeta expression in adult ventricular cardiomyocytes.
2010
Abstract The effects of statin treatment in the setting of heart failure have already been shown. Nevertheless, there is little knowledge about its influence on adrenergic pathways in cardiomyocytes. Therefore, this study investigated the impact of cerivastatin on adrenoceptor-mediated signalling pathways in isolated adult ventricular cardiomyocytes. It focused on two endpoints: hypertrophic growth and TGFbeta expression. Cultured cardiomyocytes were used to study rac activation (analysed by its translocation into the membrane fraction), ROS formation (H 2 DCF fluorescence) and hypertrophic growth ( 14 C-phenylalanine incorporation). Alpha- and beta-adrenoceptor stimulation showed significa…
MRI-visible perivascular spaces: relationship to cognition and small vessel disease MRI markers in ischaemic stroke and TIA.
2013
Background MRI-visible perivascular spaces (PVS) are potential neuroimaging markers of cerebral small vessel disease, but their functional significance and mechanisms remain uncertain. We investigated the association between PVS and cognitive impairment, and other MRI markers of small vessel disease, in a patient cohort of ischaemic stroke/transient ischaemic attack (TIA) referrals. Methods Data were collected from a prospective observational database. Standardised detailed neuropsychological testing was performed. A validated visual rating scale on T-2-weighted MRI was used to categorise PVS severity; validated scales were used to assess white matter hyperintensities (WMH), cerebral microb…
Long-Term Response to Cholinesterase Inhibitor Treatment Is Related to Functional MRI Response in Alzheimer's Disease.
2015
<b><i>Background:</i></b> Treatment of Alzheimer's disease (AD) with cholinesterase inhibitors (ChEI) enhances cholinergic activity and alleviates clinical symptoms. However, there is variation in the clinical response as well as system level changes revealed by functional MRI (fMRI) studies. <b><i>Methods:</i></b> We investigated 18 newly diagnosed mild AD patients with fMRI using a face recognition task after a single oral dose of rivastigmine, a single dose of placebo and 1-month treatment with rivastigmine. The clinical follow-up took place at 6 and 12 months. <b><i>Results:</i></b> MMSE score difference between bas…
Amphiphilic polyaspartamide copolymer-based micelles for rivastigmine delivery to neuronal cells
2012
A novel polysorbate-80 (PS(80))-attached amphiphilic copolymer comprising a hydrophilic α,β-poly(N-2-hydroxyethyl)-D,L-aspartamide (PHEA) backbone and hydrophobic squalenyl-C(17) (Sq(17)) portions was synthesized and characterized; the formation of polymeric micelles was also evaluated. Rivastigmine free-base (Riv), a hydrophobic drug employed to treat Alzheimer's disease, was chosen as model drug to investigate micelle's ability to incorporate hydrophobic molecules and target them to neuronal cells. Micelle formation was studied through analyses including fluorescence spectroscopy and 2D (1)H-NMR NOESY experiments. Finally, the capacity of Riv-loaded micelles, versus free drug, to penetrat…
A NANOPARTICULATE DRUG-DELIVERY SYSTEM FOR RIVASTIGMINE: PHYSICO-CHEMICAL AND IN VITRO BIOLOGICAL CHARACTERIZATION
2007
The preparation and characterization of surface-PE Gylated polymeric nanoparticles are described. These systems were obtained by UV irradiation of PHM and PHM-PEG(2000) as an inverse microemulsion, using an aqueous solution of the PHM/PHM-PEG(2000) copolymer mixture as the internal phase and triacetin saturated with water as the external phase, and characterized by dimensional analysis, zeta-potential measurements and XPS. in vitro biological tests demonstrated their cell compatibility and their ability to escape from phagocytosis. Rivastigmine was encapsulated into the nanoparticle structure and drug-release profiles from loaded samples were investigated in PBS at pH = 7.4 and human plasma.