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1.
Nanotechnology ; 23(38): 385604, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22947598

RESUMO

Multiwall carbon nanotubes grown by plasma enhanced chemical vapour deposition were functionalized by H(2)O plasma treatment. Through a controlled functionalization process of the carbon nanotubes (CNTs) we were able to modify and tune their chemical reactivity, expanding the range of potential applications in the field of energy and environment. In particular, different oxygen groups were attached to the surfaces of the nanotubes (e.g. carboxyl, hydroxyl and carbonyl), which changed their physicochemical properties. In order to optimize the main operational parameters of the H(2)O plasma treatment, pressure and power, a Box-Wilson experimental design was adopted. Analysis of the morphology, electrochemical properties and functional groups attached to the surfaces of the CNTs allowed us to determine which treatment conditions were suitable for different applications. After water plasma treatment the specific capacitance of the nanotubes increased from 23 up to 68 F g(-1) at a scan rate of 10 mV s(-1).


Assuntos
Cristalização/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Gases em Plasma/química , Água/química , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
2.
Benef Microbes ; 13(1): 25-31, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-34794372

RESUMO

According to previous research, the incidence of necrotising enterocolitis (NEC) decreases after supplementation with probiotics. However, few studies have considered the equivalence or otherwise of different strains of probiotics in this respect. Accordingly, this prospective observational study was conducted in a cohort of 245 very-low-birth-weight (VLBW) new-borns to assess the prevalence of NEC after supplementation with the probiotic Inforan® (Berna Biotech, Madrid, Spain) 250 mg capsules containing 109 cfu of Lactobacillus acidophilus (ATCC 4356) and 109 cfu of Bifidobacterium bifidum (ATCC 15696); or with Bivos® (Ferring, Madrid, Spain) containing Lacticaseibacillus (formerly Lactobacillus) rhamnnosus (LGG) (ATCC 53103) (109 cfu); or with no probiotic supplementation. Statistical analysis was performed using multivariant regression for the duration of parenteral nutrition, length of neonatal intensive care unit stay, use of oxygen therapy and presence of chorioamnionitis. Of the VLBW new-borns in the study group, 65 received Infloran, 108 received Bivos and 72 received no probiotic. A significant association was observed between a reduced presence of NEC Stage ≥2 and probiotic supplementation. The odds risk (OR) obtained was 0.174 (95% confidence interval (CI): 0.032-0.936) for Infloran and 0.196 (95%CI: 0.053-0.732) for Bivos. Therefore, both probiotics are associated with a lower prevalence of NEC in VLBW new-borns, with no significant differences.


Assuntos
Enterocolite Necrosante , Probióticos , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/prevenção & controle , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Lactobacillus acidophilus , Probióticos/uso terapêutico
3.
Arch Environ Contam Toxicol ; 59(1): 49-61, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20082069

RESUMO

The distribution and potential sources of 16 polycyclic aromatic hydrocarbons (PAHs) in sediment cores (<63 microm particle size) of the Sundarban mangrove wetland, northeastern coast of Bay of Bengal (India), were investigated by gas chromatography coupled to mass spectrometry. The total concentrations of 16 PAHs ( summation operator(16)PAHs) ranged from 132 to 2938 ng/g, with a mean of 634 ng/g, and the sum of 10 out of 16 priority PAHs ( summation operator(10)PAH) varied from 123 to 2441 ng/g, with a mean of 555 ng/g, and the 5 carcinogenic PAHs (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, and dibenz[a,h]anthracene) accounted for 68-73% of the priority PAHs. Maximum concentrations of the sediment core were obtained at subsoil depth of 12-16 cm. The prevalence of four to six aromatic ring PAHs and cross-plots of specific isomer ratios such as phenanthrene/anthracene, fluoranthene/pyrene, and methylphenanthrenes/phenanthrene suggested the predominance of wood and coal combustion sources, the atmospheric deposition, and surface runoff to be the major transport pathways. A good correlation existed between the benzo[a]pyrene level and the total PAH concentrations, making this compound a potential molecular marker for PAH pollution. Total TEQ (S) (carc) values calculated for samples varied from 6.95 ng/g TEQ (S) (carc) to 119 ng/g TEQ (S) (carc) , with an average of 59 ng/g dry weight TEQ (S) (carc) . The baseline data can be used for regular monitoring, considering the industrial and agricultural growth around this coastal environment.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Áreas Alagadas , Avicennia , Índia , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
4.
Ann Dermatol Venereol ; 136 Suppl 4: S73-6, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-19576489

RESUMO

Several bacteria of the Clostridium genus (C. botulinum) produce 150 kDa di-chainal protein toxins referred as botulinum neurotoxins or BoNTs. They associate with non-toxic companion proteins and form a complex termed botulinum toxin. BoNTs specifically inhibit vesicular neurotransmitter release. The cellular action of BoNTs can be depicted according to a multi-step model : The toxin's heavy chain mediates binding to specific receptors comprised of a ganglioside moiety and a vesicular protein (SV2 for BoNT type A, synaptotagmin for BoNT type B), followed by endocytotic internalisation of the BoNT/receptor complex. Vesicle recycling induces BoNT internalisation. Upon acidification of vesicles, the light chain of the neurotoxin is translocated into the cytosol. Here, this zinc-endopeptidase cleaves one or two among three synaptic proteins (VAMP-synapto-brevin, SNAP25, and syntaxin). As the three protein targets of BoNT play major role in fusion of synaptic vesicles at the release sites, their cleavage is followed by blockade of neurotransmitter exocytosis. Importantly, as the BoNT receptors and intracellular targets are present in all nerve terminals, the BoNTs are not specific for cholinergic transmission. Duration of their inhibitory action is mainly determined by the the life-time of the toxin's light chain in the cytosol. Sprouting of new nerve-endings, which are retracted when the poisoned nerve terminals have recovered full functionality, may lead to anticipated recovery of the poisoned nerve terminals.


Assuntos
Toxinas Botulínicas/farmacologia , Fármacos Dermatológicos/farmacologia , Fármacos Neuromusculares/farmacologia , Toxinas Botulínicas/química , Toxinas Botulínicas/metabolismo , Clostridium botulinum/metabolismo , Fármacos Dermatológicos/química , Fármacos Dermatológicos/metabolismo , Humanos , Metaloendopeptidases/metabolismo , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Fármacos Neuromusculares/química , Fármacos Neuromusculares/metabolismo , Transmissão Sináptica/efeitos dos fármacos
5.
Rev Neurol ; 69(1): 32-38, 2019 Jul 01.
Artigo em Espanhol | MEDLINE | ID: mdl-31236909

RESUMO

INTRODUCTION: Multiple sclerosis is a chronic autoimmune, inflammatory and neurodegenerative disease of the central nervous system and the most common non-traumatic disabling neurological disease in young adults. In the latest decades, multiple sclerosis is increasing worldwide, especially in women. The latitudinal distribution has been progressively attenuated. AIM: To review the epidemiological studies of multiple sclerosis in Spain to verify if this worldwide trend also occurs in Spain. DEVELOPMENT: We searched PubMed and Teseo databases using the search terms «epidemiology¼, «prevalence¼, «incidence¼, «multiple sclerosis¼ and «Spain¼. We selected articles published in Spanish and English between 1968 and 2018. CONCLUSIONS: Recent epidemiological studies confirm that Spain is a medium-high risk area for MS. The prevalence of MS has increased significantly throughout Spain in the latest years, especially in women, and recent studies show prevalence as high as 80-180 cases per 100,000.


TITLE: Epidemiologia de la esclerosis multiple en España.Introduccion. La esclerosis multiple es una enfermedad cronica autoinmune, inflamatoria y degenerativa del sistema nervioso central, y es el trastorno neurologico discapacitante no traumatico mas comun en adultos jovenes. Los estudios de prevalencia mas recientes indican que la frecuencia de la enfermedad ha aumentado en el mundo en las ultimas decadas, que dicho incremento de la prevalencia ocurre fundamentalmente a expensas de un mayor numero de casos de mujeres con formas remitentes, y que el gradiente latitudinal de la incidencia de la enfermedad se viene atenuando. Objetivo. Revisar los estudios sobre epidemiologia de esclerosis multiple en España para verificar si las tendencias mundiales se confirman en nuestro pais. Desarrollo. Busqueda bibliografica en las bases de datos PubMed y Teseo usando como palabras clave «epidemiology¼, «prevalence¼ e «incidence¼, cruzandolas con los terminos «multiple sclerosis¼ y «Spain¼; se realiza una seleccion inicial por titulo y resumen, en castellano e ingles, entre los años 1968 y 2018. Conclusiones. Un buen numero de estudios epidemiologicos recientes en España confirman que es una region de prevalencia media-alta de la enfermedad a lo largo de su geografia. Las cifras de prevalencia aumentan progresivamente a lo largo de las ultimas decadas hasta alcanzar en la actualidad 80-180 casos por 100.000 habitantes, y ello ha ocurrido a expensas de una mayor frecuencia de la enfermedad en las mujeres.


Assuntos
Esclerose Múltipla/epidemiologia , Humanos , Incidência , Prevalência , Espanha/epidemiologia
6.
Brain Res ; 1704: 94-102, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30287342

RESUMO

In this work visual functional improvement of amblyopic Long Evans rats treated with tDCS has been assessed using the "slow angled-descent forepaw grasping" (SLAG) test. This test is based on an innate response that does not requires any memory-learning component and has been used before for measuring visual function in rodents. The results obtained show that this procedure is useful to assess monocular but not binocular deficits, as controls and amblyopic animals showed significant differences during monocular but not during binocular assessment. On the other hand, parvoalbumin labelling was analysed in three areas of the visual cortex (V1M, V1B and V2L) before and after tDCS treatment. No changes in labelling were observed after monocular deprivation. However, tDCS treatment significantly improved vision through the amblyopic eye, and a significant increase of parvoalbumin-positive cells was observed in the three areas, both in the stimulated hemisphere but also in the non-stimulated hemisphere. This effect occurred both in control and amblyopic animals. Thus, tDCS induced changes are similar in controls and amblyopic animals, although only the last one showed a functional improvement.


Assuntos
Ambliopia/terapia , Neurônios/metabolismo , Parvalbuminas/metabolismo , Visão Ocular/fisiologia , Córtex Visual/fisiopatologia , Percepção Visual/fisiologia , Ambliopia/metabolismo , Ambliopia/fisiopatologia , Animais , Sensibilidades de Contraste/fisiologia , Masculino , Estimulação Luminosa , Ratos , Ratos Long-Evans , Estimulação Transcraniana por Corrente Contínua , Córtex Visual/metabolismo
7.
J Prev Med Hyg ; 48(2): 43-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17713137

RESUMO

In this work, a methodology for the determination of total mercury in human hair is presented. This methodology is an improvement of a previous technique which has been reported by Chen et al. in 2002. This previous work was based on an acid digestion, C, cartridge clean-up, a 2,3-dimercaptopropane-1-sulfonate complexing agent, solid phase extraction and a graphite furnace atomic absorption spectrophotometric determination. In the present study, the complexing agent has been replaced by the ammonium pyrrolidine dithiocarbamate followed by a liquid-liquid extraction and the clean-up has been avoided in order to obtain a less expensive and less time consuming methodology.


Assuntos
Cabelo , Mercúrio/análise , Espectrofotometria Atômica , Humanos
8.
J Chromatogr A ; 1083(1-2): 1-6, 2005 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-16078681

RESUMO

A procedure for the determination of perfluorocarboxylic acids (i.e. PFC7-10A) in sediment by pressurized fluid extraction (PFE), derivatization, headspace solid-phase microextraction and GC-MS determination in the negative ion chemical ionisation mode was developed. The PFE extraction variables such as solvent composition, number and time per extraction cycle, and extraction temperature were optimised. In the optimum extraction conditions, recoveries exceeding 95% with a limit of detection and RSDs of 0.5-0.8 ng g(-1) and 15.5-16.8%, respectively, were obtained. The developed analytical procedure was applied to harbour sediments where PFC8A and PFC10A were detected for the first time at low ppb concentrations (i.e. 8-11 ng g(-1).


Assuntos
Ácidos Carboxílicos/análise , Fracionamento Químico/métodos , Fluorocarbonos/análise , Sedimentos Geológicos/química , Ácidos Carboxílicos/isolamento & purificação , Fluorocarbonos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Solventes
9.
An Pediatr (Barc) ; 82(6): 397-403, 2015 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-25300782

RESUMO

OBJECTIVE: Cranberry prophylaxis of recurrent urinary tract infection in infants has proven effective in the experimental model of the adult. There are few data on its efficacy, safety and recommended dose in the pediatric population. METHODS: A controlled, double-blind Phase III clinical trial was conducted on children older than 1 month of age to evaluate the efficacy and safety of cranberry in recurrent urinary tract infection. The assumption was of the non-inferiority of cranberry versus trimethoprim. Statistical analysis was performed using Kaplan Meier analysis. RESULTS: A total of 85 patients under 1 year of age and 107 over 1 year were recruited. Trimethoprim was prescribed to 75 patients and 117 received cranberry. The cumulative rate of urinary infection associated with cranberry prophylaxis in children under 1 year was 46% (95% CI; 23-70) in children and 17% (95% CI; 0-38) in girls, effectively at doses inferior to trimethoprim. In children over 1 year-old cranberry was not inferior to trimethoprim, with a cumulative rate of urine infection of 26% (95% CI; 12-41). The cranberry was well tolerated and with no new adverse effects. CONCLUSIONS: Our study confirms that cranberry is safe and effective in the prophylaxis of recurrent urinary tract infection in infants and children. With the doses used, their efficiency is not less than that observed for trimethoprim among those over 1 year-old. (Clinical Trials Registry ISRCTN16968287).


Assuntos
Sucos de Frutas e Vegetais , Fitoterapia , Infecções Urinárias/prevenção & controle , Vaccinium macrocarpon , Adolescente , Criança , Pré-Escolar , Árvores de Decisões , Método Duplo-Cego , Feminino , Sucos de Frutas e Vegetais/efeitos adversos , Humanos , Lactente , Masculino , Recidiva , Resultado do Tratamento
10.
Brain Res Mol Brain Res ; 37(1-2): 116-24, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8738142

RESUMO

The expression of rat brain sodium channel alpha-subunit (Na+I, Na+II and Na+III) and beta 1-subunit mRNAs was examined in rat fetal brain neurons in culture. A combined technique of reverse transcription and polymerase chain reaction (RT-PCR) was used. Two different PCR primer sets were designed to obtain simultaneous amplification of the three alpha-subunit mRNAs. All three molecules were detected in fetal neurons but the expression pattern (Na+III > Na+II > > Na+I) was different than that observed in adult tissue (Na+II > Na+I > Na+III). Expression of the beta 1-subunit mRNA was detected using a specific PCR primer set. Doublet bands were amplified, from fetal cells and adult brain mRNA. To get further insight into the molecular mechanism that underlie activity dependent plasticity of sodium channels, we studied the effect on the expression of sodium channel subunits mRNA of a 60 h incubation of cells in the presence of a scorpion neurotoxin that blocks channel inactivation. An overall decrease in the expression of all three alpha-subunit mRNAs was observed whereas the beta 1-subunit mRNA was unaffected by the same treatment. When cells were incubated with the scorpion neurotoxin together with tetrodotoxin, to block Na+ influx through channels, the decrease in mRNA expression was not observed. Finally, a 60 h continuous depolarization of cells induced by application of a high concentration KC1 solution did not mimic the effect of the scorpion toxin. These observations suggest that a persistent activation of the sodium channels is able to down-regulate mRNA expression for alpha-subunits but not for the beta 1-subunit.


Assuntos
Encéfalo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Canais de Sódio/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Células Cultivadas , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Ratos , Fatores de Tempo
11.
Brain Res Mol Brain Res ; 96(1-2): 1-13, 2001 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11731003

RESUMO

In neurones, the morphological complexity of the dendritic tree requires regulated growth and the appropriate targeting of membrane components. Accurate delivery of specific supplies depends on the translocation and fusion of transport vesicles. Vesicle SNAREs (soluble N-ethylmaleimide sensitive factor attachment protein receptors) and target membrane SNAREs play a central role in the correct execution of fusion events, and mediate interactions with molecules that endow the system with appropriate regulation. Synaptotagmins, a family of Ca(2+)-sensor proteins that includes neurone-specific members involved in regulating neurotransmitter exocytosis, are among the molecules that can tune the fusion mechanism. Using immunocytochemistry, confocal and electron microscopy, the localisation of synaptotagmin I in the dendrites of cultured rat hypothalamic neurones was demonstrated. Synaptotagmin labelling is concentrated at dendritic branch points, and in microprocesses. Following depolarisation, the N-terminal domain of synaptotagmin was detected at the extracellular surface of the dendritic plasma membrane. The insertion of synaptotagmin in the plasma membrane was elicited by L-type Ca(2+) channel activation and by mobilisation of the internal ryanodine-sensitive Ca(2+)stores. Furthermore, the localisation of L-type Ca(2+) channels and of ryanodine receptors, relative to the localisation of synaptotagmin in dendrites, suggests that both Ca(2+) entry and intracellular Ca(2+) stores may contribute to the fusion of dendritic transport vesicles with the membrane. Fusion is likely to involve SNAP-25 and syntaxin 1 as both proteins were also identified in dendrites. Taken together these results suggest a putative regulatory role of synaptotagmins in the membrane fusion events that contribute to shaping the dendritic tree during development.


Assuntos
Proteínas de Ligação ao Cálcio , Cálcio/metabolismo , Membrana Celular/metabolismo , Dendritos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Transporte Vesicular , Animais , Canais de Cálcio Tipo L/análise , Membrana Celular/química , Membrana Celular/ultraestrutura , Células Cultivadas , Dendritos/química , Dendritos/ultraestrutura , Hipotálamo/citologia , Hipotálamo/crescimento & desenvolvimento , Fusão de Membrana/fisiologia , Glicoproteínas de Membrana/análise , Potenciais da Membrana/fisiologia , Proteínas de Membrana/análise , Microscopia Eletrônica , Proteínas do Tecido Nervoso/análise , Neurônios/metabolismo , Neurônios/ultraestrutura , Ratos , Ratos Wistar , Canal de Liberação de Cálcio do Receptor de Rianodina/análise , Proteínas SNARE , Sinaptotagmina I , Sinaptotagminas , Sintaxina 1
12.
Brain Res Mol Brain Res ; 56(1-2): 238-55, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9602139

RESUMO

In primary cultures of fetal neurons, activation of sodium channels with either alpha-scorpion toxin or veratridine caused a rapid and persistent decrease of mRNAs encoding beta2 and different sodium channel alpha mRNAs. In contrast, beta1 subunit mRNA was up-regulated by sodium channel activation. This phenomenon was calcium-independent. The effects of activating toxins on mRNAs of different sodium channel subunits were mimicked by membrane depolarization. An important aspect of this study was the demonstration that cAMP also caused rapid reduction of alphaI, alphaII and alphaIII mRNA levels whereas beta1 subunit mRNA was up regulated and beta2 subunit mRNA was not affected. Sodium channel activation by veratridine was shown to increase cAMP immunoreactivity in cultured neurons, but alphaII mRNA down-regulation induced by activating toxins was not reversed by protein kinase A antagonists, indicating that this phenomenon is not protein kinase A dependent. The effects of cAMP and membrane depolarisation were antagonized by the PKA inhibitor H89. These results are indicative of the existence of multiple and independent regulatory pathways modulating the expression of sodium channel genes in the developing central nervous system.


Assuntos
Regulação da Expressão Gênica , Neurônios/metabolismo , Canais de Sódio/genética , Animais , Encéfalo/embriologia , Encéfalo/metabolismo , Diferenciação Celular/genética , Células Cultivadas , Desenvolvimento Embrionário e Fetal/genética , Neurônios/fisiologia , Ratos , Canais de Sódio/biossíntese , Canais de Sódio/efeitos dos fármacos
13.
Clin Chim Acta ; 108(1): 25-30, 1980 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-7470245

RESUMO

We have compared the concentrations of serum lipoprotein apoproteins in 55 ischaemic heart disease (IHD) patients and 116 apparently healthy control subjects by a simple, precise and reasonably sensitive "rocket" electroimmunoassay technique. Apolipoprotein B and apolipoprotein C levels in the vaery low density lipoprotein class and apolipoprotein B in the low density lipoprotein class were significantly lower IHD patients than in control subjects (p < 0.001). Apolipoprotein A levels within high density lipoproteins were markedly lower in a subpopulation of IHD patients compared with age-and sex-matched controls (p < 0.05). Using levels in excess of the 95th percentile of the levels in the healthy control population to delineate "abnormalities", we showed that there were more patients with "abnormalities" when lipoprotein apoprotein measurements were considered than when lipoprotein lipids were considered. The positive correlations between lipoprotein lipids and their apoproteins were in most instances greater in IHD patients than in controls.


Assuntos
Apolipoproteínas/sangue , Doença das Coronárias/sangue , Adulto , Idoso , Apolipoproteínas A , Apolipoproteínas B , Apolipoproteínas C , Colesterol/sangue , Feminino , Humanos , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
14.
Toxicon ; 20(1): 9-16, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6281941

RESUMO

The action of the neurotoxin in Buthinae scorpion venoms (Androctonus, Buthus or Leiurus genera) has been extensively studied. These proteins induce a prolongation of the action potential of nerves and muscles by slowing down inactivation of the sodium channel. Their affinity for their receptor site depends on membrane potential. In the present report we describe a toxin from a Centrurinae scorpion, Centruroides suffusus, which binds rat brain synaptosomes at a receptor site distinct from the Buthinae scorpion site independently of voltage. We name Androctonus-like toxins, alpha-scorpion toxins (alpha-ScTX), and Centruroides-like toxins, beta-scorpion toxins (beta-ScTX). We further report that beta-ScTX induces repetitive firing in frog myelinated nerve fibres by producing an abnormal sodium permeability. The beta-toxin binds specifically to rat brain synaptosomes (Kd = 3 nM) and induces an inhibition of the uptake and a stimulation of the release of GABA at concentrations which are in good agreement with the Kd value. These effects are blocked by tetrodotoxin. The binding site of beta -ScTX is distinct from those of other neurotoxins acting on the sodium channel like tetrodotoxin, alpha-ScTX and veratridine. The alpha-ScTX/beta-ScTX binding site capacities decreases as development of rat brain synaptosomes progresses ; at day 7 after birth, it is 1.1. and at day 39, 0.3.


Assuntos
Encéfalo/metabolismo , Canais Iônicos/fisiologia , Neurotoxinas/metabolismo , Receptores Colinérgicos/fisiologia , Venenos de Escorpião/metabolismo , Canais de Sódio , Sódio/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Neurotoxinas/farmacologia , Ratos , Venenos de Escorpião/farmacologia , Sinaptossomos/metabolismo
15.
J Chromatogr A ; 1025(1): 71-5, 2004 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-14753673

RESUMO

Improvements in the methylmercury extraction from human hair by solid-phase microextraction followed by gas chromatography coupled to cold-vapour atomic fluorescence spectrometry (GC-CVAFS) have been carried out. They consisted in the optimisation of the digestion step prior to the aqueous-phase ethylation and in the GC-CVAFS interface set-up. The main digestion parameters such as acid type, concentration, temperature and time have been optimised for hair sample analysis, thereby avoiding methylmercury degradation. Moreover, the stability of the digested samples was evaluated to improve the sample throughput.


Assuntos
Cromatografia Gasosa/métodos , Cabelo/química , Compostos de Metilmercúrio/isolamento & purificação , Espectrometria de Fluorescência/métodos , Humanos
16.
Med Clin (Barc) ; 106(20): 776-9, 1996 May 25.
Artigo em Espanhol | MEDLINE | ID: mdl-8801396

RESUMO

BACKGROUND: The well-known relationship between high plasma cholesterol levels and coronary heart disease makes the treatment of primary hypercholesterolemia an important issue. PATIENTS AND METHODS: A randomized, double-blind 12 week study to compare lovastatin (20-80 mg/day) and gemfibrozil (600 mg b.i.d.) was performed in 59 patients with primary hypercholesterolemia. Resincholestyramine was started on week 12, at a dose of 8-16 g/day for the next 12 weeks in any patient whose LDL-cholesterol exceeded 165 mg/dl at week 12. RESULTS: Total cholesterol, triglycerides and LDL-cholesterol decreased significantly (23.8%, 16.4% and 30.9%, respectively) after lovastatin therapy, whereas HDL-cholesterol increased (13.9%). The figures for the group treated with gemfibrozil were 12.8%, 30.3%, 17.2% and 14.6%, respectively. Mean changes between the two groups were statistically significant for all parameters except for HDL-cholesterol. LDL-cholesterol decreased below 165 mg/dl in 69% of patients receiving lovastatin and 36.7% of patients treated with gemfibrozil (p < 0.05). During the second phase there were no additional significant changes in the 9 patients of the lovastatin group and the 20 patients of the gemfibrozil group after cholestyramine, but LDL-cholesterol decreased below 165 mg/dl in 5 patients (55%) and 6 patients (30%), respectively. Side-effects were more prevalent in patients treated with gemfibrozil alone or in combination with cholestyramine. CONCLUSIONS: In patients with primary hypercholesterolemia, lovastatin alone or in combination with cholestyramine was more effective than gemfibrozil alone or in combination with cholestyramine to lower total cholesterol and LDL-cholesterol. The effect of both drugs on HDL-cholesterol was similar.


Assuntos
Anticolesterolemiantes/administração & dosagem , Resina de Colestiramina/administração & dosagem , Genfibrozila/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Lovastatina/administração & dosagem , Adolescente , Adulto , Idoso , Colesterol/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Hipercolesterolemia/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
17.
Environ Technol ; 24(12): 1465-70, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14977142

RESUMO

Volatile fatty acids (C2-C7) analysis in wool scouring water and lanolin is presented. These substances are of major interest as malodorous compounds in urban and industrial wastewaters. In this work, they have been analysed in wool scouring water by headspace solid-phase microextraction followed by gas chromatography negative chemical ionisation mass spectrometry. Most of the volatile fatty acids have been identified at microg g(-1) levels. In addition, since lanolin is a major impurity of raw wool, volatile fatty acid patterns of wool scouring water and lanolin have been compared in order to establish the origin of these compounds in the wastewater. Finally, the efficiency of the deodorization step, mandatory to obtain commercial lanolin, has been assessed taking into account the decrease in volatile fatty acid content from the raw wool to the lanolin.


Assuntos
Ácidos Graxos Voláteis/análise , Lanolina/química , Odorantes/análise , , Animais , Resíduos Industriais , Eliminação de Resíduos Líquidos
18.
Curr Med Chem ; 19(3): 406-27, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22335515

RESUMO

Platelet activation is a complex mechanism of response to vascular injury and atherothrombotic disease, leading to thrombus formation. A wide variety of surface receptors -integrins, leucine-rich family receptors, G protein coupled receptors, tyrosine kinase receptors- and intraplatelet molecules support and regulate platelet activation. They are potential targets of antiplatelet therapy for the prevention and treatment of arterial thrombosis. Despite the overall clinical benefit of established antiplatelet drugs targeting cyclooxigenase-1 (COX-1), glycoprotein integrin αIIbß3, and the purinergic P2Y(12) receptor of adenosine diphosphate, a significant proportion of treated patients continue to experience recurrent ischaemic events. This may be in partly attributed to insufficient inhibition of platelet activation. In addition, it should not be underestimated that these drugs are not immune from bleeding complications. The substantial progress in understating the regulation of platelet activation has played a key role in the development of novel antiplatelet agents. Current examples of drug under development and evaluation include: novel P2Y(12) receptor inhibitors (prasugrel, ticagrelor, cangrelor, and elinogrel), thrombin receptor PAR-1 antagonists (vorapaxar, atopaxar), new integrin glycoprotein IIb/IIIa inhibitors, and inhibitors targeting the thromboxane receptor (TP), phosphodiesterases, the collagen receptor glycoprotein VI, and intraplatelet signalling molecules. This review summarizes the mechanisms of action and current clinical evaluation of these novel antiplatelet agents.


Assuntos
Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/uso terapêutico , Humanos , Modelos Biológicos , Doadores de Óxido Nítrico/farmacologia , Doadores de Óxido Nítrico/uso terapêutico , Inibidores de Fosfodiesterase/farmacologia , Inibidores de Fosfodiesterase/uso terapêutico , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Antagonistas do Receptor Purinérgico P2/química , Antagonistas do Receptor Purinérgico P2/farmacologia , Antagonistas do Receptor Purinérgico P2/uso terapêutico , Receptor PAR-1/antagonistas & inibidores , Receptor PAR-1/metabolismo , Receptores de Tromboxanos/antagonistas & inibidores , Receptores de Tromboxanos/metabolismo , Trombose/tratamento farmacológico , Trombose/prevenção & controle
19.
J Thromb Haemost ; 10(8): 1500-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22681487

RESUMO

UNLABELLED: There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high-sensitivity interleukin-6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events. METHODS: We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0-3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed-up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded. RESULTS: At follow-up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46-3.35, P<0.001) for high hsTnT and 1.97 (1.29-3.02, P=0.002) for high hsIL6, for adverse cardiovascular events. For all-cause mortality, the HRs were 1.79 (1.13-2.83, P=0.013) and 2.48 (1.60-3.85, P<0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2 DS2-VASc) were improved by the addition of hsTnT and/or hsIL6 (all P<0.05). CONCLUSION: In a large 'real world' cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long-term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Interleucina-6/sangue , Acidente Vascular Cerebral/prevenção & controle , Tromboembolia/prevenção & controle , Troponina T/sangue , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , Fibrilação Atrial/sangue , Fibrilação Atrial/mortalidade , Biomarcadores/sangue , Feminino , Hemorragia/induzido quimicamente , Hemorragia/mortalidade , Humanos , Imunoensaio , Coeficiente Internacional Normatizado , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Espanha , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/mortalidade , Tromboembolia/sangue , Tromboembolia/mortalidade , Fatores de Tempo , Resultado do Tratamento , Regulação para Cima
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