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1.
Artigo em Inglês | MEDLINE | ID: mdl-31810431

RESUMO

An observational study in 208 volunteers in households from 30 Spanish provinces was conducted from May to June 2017 in order to evaluate the formation of acrylamide during the preparation of French fries from fresh potatoes. Consumer cooking practices and household typology were evaluated with an ad-hoc questionnaire. Potatoes (fresh and fried) and frying oil were collected from the households. A total of 36.1% of samples contained acrylamide above the benchmark level for French fries (500 µg kg-1). The mean acrylamide content (550 µg kg-1) and P95 (1747 µg kg-1) were higher than values reported by EFSA (308 µg kg-1 and 971 µg kg-1, respectively). Although the colour 'golden' was the criteria to decide the end-point of frying, nearly 40% of the consumers misclassified it. Acrylamide was significantly correlated with the colour parameter a*, even in this random scenario of frying practices, and is able to distinguish above and below the established benchmark level of 500 µg kg-1 for acrylamide.


Assuntos
Acrilamida/análise , Culinária/métodos , Análise de Alimentos , Solanum tuberosum/química , Adulto , Aminoácidos/química , Cor , Ácidos Graxos/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espanha
2.
Anim Genet ; 50(4): 381-385, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31179563

RESUMO

Polledness has been shown to have autosomal Mendelian inheritance, with the polled locus being dominant to the horned locus. This trait was mapped to the BTA1 centromeric end in several breeds. One of the distinctive attributes of Creole cattle, such as the Argentinean Creole, is the presence of long, lyre-shaped horns. However, polled native animals were reported before the introduction of modern selected European breeds. Here, we studied the origin of the polled mutation, either independent or introgressed, in a Creole line from the Creole cattle founder group at the IIACS-INTA Leales Experimental Station (northwest Argentina). The study sample (65 animals: 26 horned and 39 polled) was genotyped using high-density SNP microarrays and three previously reported genetic markers (P202 ID , P80kb ID and PG ). A genome-wide association study, selection signatures, linkage disequilibrium analysis and copy number variations were used to detect the responsible region and the segregating haplotypes/alleles. The interval mapped in the Leales herd (1.23-2.13 Mb) overlapped with the region previously reported in several European cattle breeds, suggesting that the same locus could be segregating in this population. The previously reported variants PF and PG were not detected, thus dismissing the Holstein-Friesian and Nellore origins of the polled phenotype in this native breed. Conversely, the presence of the Celtic variant PC suggests an almost complete co-segregation. The cluster analysis rejected the hypothesis of recent introgression, which is compatible with the historical record of polled Creole cattle in northwest Argentina.


Assuntos
Bovinos/genética , Cornos/fisiologia , Animais , Argentina , Bovinos/classificação , Cromossomos de Mamíferos , Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação , Mutação , Fenótipo
3.
Talanta ; 175: 313-317, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28841996

RESUMO

We report here the use of commercial screen-printed disposable sensors comprising a sputtered bismuth working electrode, a silver pseudo reference electrode and a carbon auxiliary electrode (whole set referred as BispSPE), as a new and advantageous alternative for reliable and convenient monitoring of Cd and Pb in atmospheric particulate matter (PM10 fraction) by anodic stripping voltammetry after acid digestion. After a detailed exploration of surface composition and depth profiles of the BispSPE by SEM, EDX, XPS and EIS, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring Cd and Pb with detection limits of 11.8ngmL-1 and 6.1ngmL-1 respectively. These detection limits are useful for pollution monitoring of these elements in ambient air under the requirements of international health and environmental protection standards. The accuracy of the method was assessed by voltammetric measurements of Cd and Pb in ERM®-CZ120 Fine dust (PM10-like) and ERM® 1648a Urban Particulate Matter certified reference materials. The applicability of the method to Cd and Pb determination in real samples was demonstrated by analysis of PM10 samples from the air quality network in Extremadura, with a good correlation respect to the standard ICP-MS methodology. Our work constitutes the first reference about the use of disposable sensors based on BispSPE for the determination of heavy metals in atmospheric particulate matter samples.

4.
Environ Pollut ; 218: 322-330, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27453355

RESUMO

The Punchuncaví Valley in central Chile, heavily affected by a range of anthropogenic emissions from a localized industrial complex, has been studied as a model environment for evaluating the spatial gradient of human health risk, which are mainly caused by trace elemental pollutants in soil. Soil elemental profiles in 121 samples from five selected locations representing different degrees of impact from the industrial source were used for human risk estimation. Distance to source dependent cumulative non-carcinogenic hazard indexes above 1 for children (max 4.4 - min 1.5) were found in the study area, ingestion being the most relevant risk pathway. The significance of health risk differences within the study area was confirmed by statistical analysis (ANOVA and HCA) of individual hazard index values at the five sampling locations. As was the dominant factor causing unacceptable carcinogenic risk levels for children (<10-4) at the two sampling locations which are closer to the industrial complex, whereas the risk was just in the tolerable range (10-6 - 10-4) for children and adults in the rest of the sampling locations at the study area. Furthermore, we assessed gamma ray radiation external hazard indexes and annual effective dose rate from the natural radioactivity elements (226Ra, 232Th and 40K) levels in the surface soils of the study area. The highest average values for the specific activity of 232Th (31 Bq kg-1), 40K (615 Bq kg- 1), and 226Ra (25 Bq kg-1) are lower than limit recommended by OECD, so no significant radioactive risk was detected within the study area. In addition, no significant variability of radioactive risk was observed among sampling locations.


Assuntos
Exposição Ambiental/análise , Poluentes Radioativos do Solo/análise , Adulto , Arsênio/toxicidade , Cádmio/toxicidade , Criança , Chile , Exposição Ambiental/efeitos adversos , Poluição Ambiental/análise , Humanos , Indústrias , Neoplasias/induzido quimicamente , Níquel/toxicidade , Poluentes Radioativos/análise , Medição de Risco , Solo/química , Poluentes Radioativos do Solo/toxicidade , Análise Espacial , Oligoelementos/análise
5.
Neuropharmacology ; 107: 387-395, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27044662

RESUMO

Emerging evidence suggests a complex interplay between the endocannabinoid system, omega-3 fatty acids and the immune system in the promotion of brain self-repair. However, it is unknown if all omega-3 fatty acids elicit similar effects on adult neurogenesis and if such effects are mediated or regulated by interactions with the endocannabinoid system. This study investigated the effects of DHA and EPA on neural stem cell (NSC) fate and the role of the endocannabinoid signalling pathways in these effects. EPA, but not DHA, significantly increased proliferation of NSCs compared to controls, an effect associated with enhanced levels of the endocannabinoid 2-arachidonylglycerol (2-AG) and p-p38 MAPK, effects attenuated by pre-treatment with CB1 (AM251) or CB2 (AM630) receptor antagonists. Furthermore, in NSCs derived from IL-1ß deficient mice, EPA significantly decreased proliferation and p-p38 MAPK levels compared to controls, suggesting a key role for IL-1ß signalling in the effects observed. Although DHA similarly increased 2-AG levels in wild-type NSCs, there was no concomitant increase in proliferation or p-p38 MAPK activity. In addition, in NSCs from IL-1ß deficient mice, DHA significantly increased proliferation without effects on p-P38 MAPK, suggesting effects of DHA are mediated via alternative signalling pathways. These results provide crucial new insights into the divergent effects of EPA and DHA in regulating NSC proliferation and the pathways involved, and highlight the therapeutic potential of their interplay with endocannabinoid signalling in brain repair.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Endocanabinoides/fisiologia , Células-Tronco Neurais/fisiologia , Neurogênese/fisiologia , Transdução de Sinais/fisiologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/fisiologia , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
6.
Food Funct ; 7(3): 1645-54, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26938951

RESUMO

The formation of acrylamide, hydroxymethylfurfural (HMF) and furfural was investigated in a deep fried breadcrumb coat model resembling the coat batter of breaded foods. The influence of the composition of the breadcrumb and the frying conditions on the formation of these contaminants was evaluated. Six wheat-based flour formulations of breadcrumbs were deep fried in sunflower oil at temperatures between 170-200 °C and for frying times of 1-5 minutes. Results showed significant differences in the levels of contaminants according to the concentration of the potential precursors in the breadcrumbs. HMF was influenced by the sugar content in the breadcrumbs whereas levels of acrylamide were significantly correlated with the ratio between asparagine and reducing sugars. Acrylamide, HMF and furfural were directly related to the frying time and temperature. The composition of the breadcrumb and the compounds formed during frying contributed to the total antioxidant capacity of the fried samples. The bread coat model is a useful tool in the formulation of breaded foods since it allows the evaluation of the contribution of breadcrumbs in the formation of process contaminants after frying.


Assuntos
Acrilamida/análise , Pão/análise , Culinária , Contaminação de Alimentos/análise , Furaldeído/análogos & derivados , Triticum/química , Farinha/análise , Furaldeído/análise , Temperatura Alta , Modelos Biológicos , Óleos de Plantas/química , Óleo de Girassol
7.
Chemosphere ; 144: 1788-96, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26524148

RESUMO

Fractionation of elemental contents in atmospheric samples is useful to evaluate pollution levels for risk assessment and pollution sources assignment. We present here the main results of long-term characterization of atmospheric deposition by using a recently developed atmospheric elemental fractionation sampler (AEFS) for major and trace elements monitoring around an important industrial complex located in Puchuncaví region (Chile). Atmospheric deposition samples were collected during two sampling campaigns (2010 and 2011) at four sampling locations: La Greda (LG), Los Maitenes (LM), Puchuncaví (PU) and Valle Alegre (VA). Sample digestion and ICP-MS gave elements deposition values (Al, As, Ba, Cd, Co, Cu, Fe, K, Mn, Pb, Sb, Ti, V and Zn) in the insoluble fraction of the total atmospheric deposition. Results showed that LG location, the closest location to the industrial complex, was the more polluted sampling site having the highest values for the analyzed elements. PU and LM were the next more polluted and, finally, the lowest elements concentrations were registered at VA. The application of Principal Component Analysis and Cluster Analysis identified industrial, traffic and mineral-crustal factors. We found critical loads exceedances for Pb at all sampling locations in the area affected by the industrial emissions, more significant in LG close to the industrial complex, with a trend to decrease in 2011, whereas no exceedances due to atmospheric deposition were detected for Cd.


Assuntos
Poluentes Atmosféricos/análise , Arsênio/análise , Metais/análise , Poluentes do Solo/análise , Chile , Análise por Conglomerados , Monitoramento Ambiental/métodos , Monitoramento Ambiental/estatística & dados numéricos , Indústrias , Análise de Componente Principal , Análise Espacial
8.
Neuroscience ; 284: 283-289, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25453765

RESUMO

Under inflammatory conditions, interleukin-1ß (IL-1ß) modulates neural stem cells at neurogenic niches. Here we show that spinal cord injury in rats increases IL-1ß expression in astrocytes located around the spinal cord ependyma, a region that also holds a neurogenic potential. IL-1ß increases from day 1 after lesion, reaches maximal levels between days 3 and 7, and declines from 14 days to low levels after 28 days. At the time of maximal expression, periependymal upregulation of IL-1ß extends beyond 5 mm from the epicenter of the lesion both rostral and caudally. Since IL-1ß controls proliferation and cell fate of neural stem/precursor cells, its modulation in periependymal astrocytes might create an appropriate environment for cell replacement after injury.


Assuntos
Astrócitos/metabolismo , Interleucina-1beta/metabolismo , Traumatismos da Medula Espinal/metabolismo , Medula Espinal/metabolismo , Animais , Modelos Animais de Doenças , Substância Cinzenta/metabolismo , Masculino , Células-Tronco Neurais/metabolismo , Ratos Wistar , Nicho de Células-Tronco/fisiologia , Fatores de Tempo , Regulação para Cima
9.
Talanta ; 125: 125-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24840424

RESUMO

We have developed and validated a new simple and effective methodology for fractionation of soluble and insoluble forms of trace elements in total atmospheric deposition. The proposed methodology is based on the modification of a standard total deposition passive sampler by integrating a quartz fiber filter that retains the insoluble material, allowing the soluble fraction to pass through and flow to a receiving bottle. The quartz filter containing the insoluble fraction and the liquid containing the soluble fraction are then separately assayed by standardized ICP-MS protocols. The proposed atmospheric elemental fractionation sampler (AEFS) was validated by analyzing a Coal Fly Ash reference material with proper recoveries, and tested for field fractionation of a set of 10 key trace elements in total atmospheric deposition at the industrial area of Puchuncaví-Ventanas, Chile. The AEFS was proven useful for pollution assessment and also to identify variability of the soluble and insoluble fractions of the selected elements within the study area, improving the analytical information attainable by standard passive samplers for total deposition without the need of using sophisticated and high cost wet-only/dry only collectors.


Assuntos
Monitoramento Ambiental/métodos , Oligoelementos/análise , Poluentes Atmosféricos/análise , Atmosfera , Chile , Carvão Mineral , Cinza de Carvão , Recuperação e Remediação Ambiental , Desenho de Equipamento , Filtração , Geografia , Resíduos Industriais , Indústrias , Espectrometria de Massas , Valores de Referência , Reprodutibilidade dos Testes , Solubilidade
10.
Talanta ; 101: 435-9, 2012 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-23158345

RESUMO

The applicability of commercial screen-printed gold electrodes (SPGEs) connected to a portable potentiostat and a laptop has been explored to optimize a new square wave anodic stripping voltammetric method for on-site determination of soluble Cu(II) in atmospheric deposition samples taken around an industrial complex. Electrode conditioning procedures, chemical and instrumental variables have been optimized to develop a reliable method capable of measuring dissolved copper with a detection limit of 3.7 ng mL(-1), useful for pollution monitoring or screening purposes. The proposed method was tested with the SLRS-5 River Water for Trace Metals (recoveries 109.9-113.1%) and the SPS-SW2 Batch 121 Elements in Surface Waters (recoveries 93.2-97.6%). The method was applied to soluble Cu(II) measurement in liquid samples taken by a total atmospheric deposition collector modified with a quartz filter for soluble and insoluble elemental speciation. The voltammetric measurements on field samples were tested in the lab by a reference ICP-MS method, with good agreement. The proposed method proved capability for field operation during a two weeks monitoring campaign.

11.
Br J Pharmacol ; 163(7): 1520-32, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21480865

RESUMO

BACKGROUND AND PURPOSE: The endogenous cannabinoid system participates in oligodendrocyte progenitor differentiation in vitro. To determine the effect of synthetic cannabinoids on oligodendrocyte differentiation, we exposed differentiating cultures of oligodendrocytes with cannabinoid CB(1), CB(2) and CB(1)/CB(2) receptor agonists and antagonists. The response of the PI3K/Akt and the mammalian target of rapamycin (mTOR) signalling pathways were studied as effectors of cannabinoid activity. EXPERIMENTAL APPROACH: Purified oligodendrocyte progenitor cells (OPC) obtained from primary mixed glial cell cultures were treated for 48 h with CB(1), CB(2) and CB(1) /CB(2) receptor agonists (ACEA, JWH133 and HU210, respectively) in the presence or absence of the antagonists AM281 (CB(1) receptor) and AM630 (CB(2) receptor). Moreover, inhibitors of the phosphatidylinositol 3-kinase (PI3K)/Akt and mTOR pathways (LY294002 and rapamycin, respectively) were used to study the involvement of these pathways on cannabinoid-induced OPC maturation. KEY RESULTS: ACEA, JWH133 and HU-210 enhanced OPC differentiation as assessed by the expression of stage specific antigens and myelin basic protein (MBP). Moreover, this effect was blocked by the CB receptor antagonists. ACEA, JWH133 and HU210 induced a time-dependent phosphorylation of Akt and mTOR, whereas the inhibitors of PI3K/Akt (LY294002) or of mTOR (rapamycin) reversed the effects of HU-210 on oligodendrocyte differentiation and kinase activation. CONCLUSIONS AND IMPLICATIONS: Activation of cannabinoid CB(1) or CB(2) receptors with selective agonists accelerated oligodendrocyte differentiation through the mTOR and Akt signalling pathways.


Assuntos
Oligodendroglia/efeitos dos fármacos , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Células-Tronco/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Ácidos Araquidônicos/farmacologia , Canabinoides/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Dronabinol/análogos & derivados , Dronabinol/farmacologia , Ativadores de Enzimas/farmacologia , Indóis/farmacologia , Morfolinas/farmacologia , Proteínas da Mielina/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , Proteína Oncogênica v-akt/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Pirazóis/farmacologia , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores
12.
Psychol Rep ; 108(1): 149-66, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21526601

RESUMO

Patterns of relative and absolute stability in parental behaviour with children and adolescents are reported. The sample comprised 523 youth (58.7% girls). Data were collected at three time periods: T1 (M age = 11.1 yr.), T2 (M age = 12.2 yr.), and T3 (M age = 13.2 yr.), each separated by one year. According to children's reports, relative consistency was moderate in both mothers and fathers, particularly as regards communication and strict control. In contrast, as children got older, parental rearing practices related to strict control and hostility decreased. There was a similarity between fathers and mothers in terms of relative and absolute stability. Relative stability was affected by the child's sex, the parenting variable, and the time period; however, the patterns of absolute stability reveal no differences by sex.


Assuntos
Atitude , Poder Familiar/psicologia , Psicologia do Adolescente , Adaptação Psicológica , Adolescente , Fatores Etários , Criança , Comunicação , Relações Pai-Filho , Feminino , Hostilidade , Humanos , Estudos Longitudinais , Masculino , Relações Mãe-Filho , Estudos Prospectivos , Fatores Sexuais , Controles Informais da Sociedade , Socialização
13.
Rev. méd. Chile ; 138(12): 1502-1509, dic. 2010. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-583046

RESUMO

Background: Epidemiologic studies may be used as a starting point to improve interventions and improve diagnosis, with instruments that are both reliable and adequate. Aim: To analyze the psychometric properties of the Attention Defcit Disorder Evaluation Scale (ADDES) in Chilean primary and high school students. Material and Methods: The ADDES was applied by 142 teachers to 254 students. Attention Defcit Disorder was already diagnosed in 144 students. Explanatory and confirmatory factorial analyses were carried out. Results: Confirmatory Factorial Analysis (CFA) proved that the model suggested by the authors could not be replicated in the Chilean sample. Exploratory Factorial Analysis (EFA) showed that three new factors came out of the analysis. CFA was applied to the new model and modification indexes suggested the introduction of new saturations. Based on the model with the best goodness-of-fit, psychometric characteristics were evaluated. Conclusions: The ADDES adapted to the Chilean context has a high reliability and a strong discrimination ability, allowing the evaluation of behavior disorders, hyperactivity/impulsivity and attention deficit.


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Chile/epidemiologia , Análise Fatorial , Psicometria , Reprodutibilidade dos Testes , Estudantes/estatística & dados numéricos
14.
Rev Med Chil ; 138(12): 1502-9, 2010 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-21526298

RESUMO

BACKGROUND: Epidemiologic studies may be used as a starting point to improve interventions and improve diagnosis, with instruments that are both reliable and adequate. AIM: To analyze the psychometric properties of the Attention Deficit Disorder Evaluation Scale (ADDES) in Chilean primary and high school students. MATERIAL AND METHODS: The ADDES was applied by 142 teachers to 254 students. Attention Defcit Disorder was already diagnosed in 144 students. Explanatory and confirmatory factorial analyses were carried out. RESULTS: Confirmatory Factorial Analysis (CFA) proved that the model suggested by the authors could not be replicated in the Chilean sample. Exploratory Factorial Analysis (EFA) showed that three new factors came out of the analysis. CFA was applied to the new model and modification indexes suggested the introduction of new saturations. Based on the model with the best goodness-of-fit, psychometric characteristics were evaluated. CONCLUSIONS: The ADDES adapted to the Chilean context has a high reliability and a strong discrimination ability, allowing the evaluation of behavior disorders, hyperactivity/impulsivity and attention deficit.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Criança , Chile/epidemiologia , Análise Fatorial , Feminino , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Estudantes/estatística & dados numéricos
15.
J Anim Breed Genet ; 125(3): 187-93, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18479269

RESUMO

Eight paternal half-sib families were used to identify chromosomal regions associated with variation in the lactation curves of dairy goats. DNA samples from 162 animals were amplified by PCR for 37 microsatellite markers, from Capra hircus autosomes CHI3, CHI6, CHI14 and CHI20. Milk samples were collected during 6 years, and there were 897 records for milk yield (MY) and 814 for fat (FP) and protein percentage (PP). The analysis was conducted in two stages. First, a random regression model with several fixed effects was fitted to describe the lactation function, using a scale (alpha) plus four shape parameters: beta and gamma, both associated with a decrease in the slope of the curve, and delta and phi that are related to the increase in slope. Predictions of alpha, beta, gamma, delta and phi were regressed using an interval mapping model, and F-tests were used to test for quantitative trait loci (QTL) effects. Significant (p < 0.05) QTLs were found for: (i) MY: CHI6 at 70-80 cM for all parameters; CHI14 at 14 cM for delta and phi; (ii) FP: CHI14, at 63 cM was associated with beta; CHI20, at 72 cM, showed association with alpha; (iii) PP: chromosomal regions associated with beta were found at 59 cM in CHI3 and at 55 cM in CHI20 with alpha and gamma. Analyses using more families and more animals will be useful to confirm or to reject these findings.


Assuntos
Cabras/genética , Cabras/fisiologia , Leite/metabolismo , Locos de Características Quantitativas , Animais , Cruzamento , Indústria de Laticínios/estatística & dados numéricos , Feminino , Genótipo , Lactação/genética , Lipídeos/análise , Estudos Longitudinais , Masculino , Repetições de Microssatélites , Leite/química , Proteínas do Leite/análise , Modelos Genéticos , Fenótipo , Análise de Regressão
16.
Br J Pharmacol ; 153(2): 216-25, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17891163

RESUMO

Amongst the various demyelinating diseases that affect the central nervous system, those induced by an inflammatory response stand out because of their epidemiological relevance. The best known inflammatory-induced demyelinating disease is multiple sclerosis, but the immune response is a common pathogenic mechanism in many other less common pathologies (e.g., acute disseminated encephalomyelitis and acute necrotizing haemorrhagic encephalomyelitis). In all such cases, modulation of the immune response seems to be a logical therapeutic approach. Cannabinoids are well known immunomodulatory molecules that act through CB1 and CB2 receptors. While activation of CB1 receptors has a psychotropic effect, activation of CB2 receptors alone does not. Therefore, to bypass the ethical problems that could result from the treatment of inflammation with psychotropic molecules, considerable effort is being made to study the potential therapeutic value of activating CB2 receptors. In this review we examine the current knowledge and understanding of the utility of cannabinoids as therapeutic molecules for inflammatory-mediated demyelinating pathologies. Moreover, we discuss how CB2 receptor activation is related to the modulation of immunopathogenic states.


Assuntos
Transplante de Células , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/tratamento farmacológico , Doenças Desmielinizantes/tratamento farmacológico , Receptor CB2 de Canabinoide/efeitos dos fármacos , Animais , Doenças Desmielinizantes/imunologia , Humanos , Inflamação/patologia , Receptor CB2 de Canabinoide/imunologia , Transplante de Células-Tronco
17.
J Chromatogr A ; 1165(1-2): 122-7, 2007 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17706232

RESUMO

A new method based on high-performance size-exclusion chromatography (HPSEC) is proposed to quantitate primary and secondary oxidation compounds in model fatty acid methyl esters (FAMEs). The method consists on simply injecting an aliquot sample in HPSEC, without preliminary isolation procedures neither addition of standard internal. Four groups of compounds can be quantified, namely, unoxidised FAME, oxidised FAME monomers including hydroperoxides, FAME dimers and FAME polymers. Results showed high repeatability and sensitivity, and substantial advantages versus determination of residual substrate by gas-liquid chromatography. Applicability of the method is shown through selected data obtained by numerous oxidation experiments on pure FAME, mainly methyl linoleate, at ambient and moderate temperatures.


Assuntos
Cromatografia em Gel/métodos , Ácidos Linoleicos/isolamento & purificação , Ácidos Linolênicos/isolamento & purificação , Ácidos Oleicos/isolamento & purificação , Ácidos Linoleicos/química , Ácidos Linolênicos/química , Oxirredução , Temperatura
18.
Glia ; 33(2): 97-106, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11180507

RESUMO

The objective of this study was to investigate the actions of exogenous and endogenous IL-10 on inflammatory responses of glia. Studies were conducted in primary, mixed glial cultures from C57BL/6 (wild-type [WT]) and IL-10-deficient C57BL/6 (IL-10 knockout [KO]) neonatal mice. Activation of cultures from WT mice by bacterial lipopolysaccharide (LPS, 10 ng/ml-10 microg/ml, 24 h), caused dose-dependent increases in nitric oxide (NO) and prostaglandin E(2) (PGE(2)) release. In cultures from IL-10 KO mice, LPS elicited markedly attenuated release of NO (approximately 4-fold) and PGE(2) (approximately 17-fold). In WT cultures, co-incubation with IL-10 (10 or 100 ng/ml, 24 h) inhibited the effects of LPS on release of NO (30%) and PGE(2) (40-50%). In cultures from IL-10 KO mice, the addition of IL-10 (10 or 100 ng/ml, 24 h) completely abolished LPS-induced NO and PGE(2) release. LPS did, however, release of IL-1beta and TNF-alpha in cultures from all animals. Co-incubation of WT cultures with IL-10 (1, 10, or 100 ng/ml, 24 h) dose-dependently reduced the release of IL-1beta (by 0%, 15%, 75%, respectively). In cultures from IL-10 KO mice, co-incubation with IL-10 (1, 10, or 100 ng/ml, 24 h) completely abolished LPS induced release of IL-1beta. Co-incubation with IL-10 (1, 10, 100 ng/ml) reduced, LPS-induced TNF-alpha release dose-dependently in WT cultures (by 15%, 50% and 90%) and abolished LPS-induced TNF-alpha release in cells from IL-10 KO mice. These results indicate that in glia from WT mice, exogenous IL-10 attenuates LPS-induces release of NO, PGE(2), TNF-alpha and IL-1beta. In contrast, mixed glial cultures from IL-10 KO mice showed reduced responses to LPS, but increased sensitivity to exogenous IL-10.


Assuntos
Citocinas/metabolismo , Encefalite/metabolismo , Encefalite/fisiopatologia , Interleucina-10/farmacologia , Lipopolissacarídeos/farmacologia , Neuroglia/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Dinoprostona/metabolismo , Endotoxinas/metabolismo , Citometria de Fluxo , Interleucina-1/metabolismo , Interleucina-10/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/metabolismo , Dióxido de Nitrogênio/metabolismo , Receptores de Interleucina/metabolismo , Receptores de Interleucina-10 , Choque Séptico/metabolismo , Choque Séptico/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo
19.
J Neuroimmunol ; 111(1-2): 1-9, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11063815

RESUMO

Interleukin-1beta (IL-1beta) participates in neuroinflammation and neurodegeneration. Its mechanisms of action are not fully understood, but appear to involve complex interactions between neurons and glia. The objective of this study was to determine the involvement of endogenous IL-1beta in inflammatory responses to LPS in cultured mouse glial cells, and compare this to the effects of exogenous IL-1beta. Activation of primary mixed glial cultures by incubation with LPS (1 microgram/ml, 24 h), caused marked (approximately ten-fold) increases in release of NO, twenty-fold increases in PGE(2) and ninety-fold increases of IL-6 release. Incubation with human recombinant IL-1beta (100 ng/ml) also stimulated NO and IL-6 release to a similar extent to LPS, but IL-1beta (1 or 100 ng/ml) caused only modest increases (approximately seven-fold) in PGE(2) release. Co-incubation with IL-1ra inhibited the effects of LPS on NO release (-65%) and IL-6 production (-30%), but failed to reduce PGE(2) release. These results indicate that exogenous IL-1beta induces release of NO, PGE(2) and IL-6 in mixed glial cultures, and that endogenous IL-1beta mediates inflammatory actions of LPS on NO and to a lesser extent IL-6, but not on PGE(2) release in mixed glial cultures. Indeed endogenous IL-1beta appears to inhibit LPS-induced PGE(2) release.


Assuntos
Interleucina-1/imunologia , Interleucina-1/farmacologia , Neuroglia/imunologia , Animais , Células Cultivadas , Dinoprostona/metabolismo , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/farmacologia , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Óxido Nítrico/metabolismo , Sialoglicoproteínas/farmacologia , Organismos Livres de Patógenos Específicos
20.
Br J Pharmacol ; 131(1): 152-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10960082

RESUMO

Interleukin-1 (IL-1) is an important mediator of immunoinflammatory responses in the brain. In the present study, we examined whether prostaglandin E(2) (PGE(2)) production after IL-1beta stimulation is dependent upon activation of protein kinases in astroglial cells. Astrocyte cultures stimulated with IL-1beta or the phorbol ester, PMA significantly increased PGE(2) secretion. The stimulatory action of IL-1beta on PGE(2) production was totally abolished by NS-398, a specific inhibitor of cyclo-oxygenase-2 activity, as well as by the protein synthesis inhibitor cycloheximide, and the glucocorticoid dexamethasone. Furthermore, IL-1beta induced the expression of COX-2 mRNA. This occurred early at 2 h, with a maximum at 4 h and declined at 12 h. IL-1 beta treatment also induced the expression of COX-2 protein as determined by immunoblot analysis. In that case the expression of the protein remained high at least up to 12 h. Treatment of cells with protein kinase C inhibitors (H-7, bisindolylmaleimide and calphostin C) inhibited IL-1beta stimulation of PGE(2). In addition, PKC-depleted astrocyte cultures by overnight treatment with PMA no longer responded to PMA or IL-1. The ablation of the effects of PMA and IL-1beta on PGE(2) production, likely results from down-regulation of phorbol ester sensitive-PKC isoenzymes. Immunoblot analysis demonstrated the translocation of the conventional isoform cPKC-alpha from cytosol to membrane following treatment with IL-1beta. In addition, IL-1beta treatment led to activation of extracellular signal-regulated kinase (ERK1/2) and p38 subgroups of MAP kinases in astroglial cells. Interestingly, the inhibition of ERK kinase with PD 98059, as well as the inhibition of p38 MAPK with SB 203580, prevented IL-1beta-induced PGE(2) release. ERK1/2 activation by IL-1beta was sensitive to inhibition by the PKC inhibitor bisindolylmaleimide suggesting that ERK phosphorylation is a downstream signal of PKC activation. These results suggest key roles for PKC as well as for ERK1/2 and p38 MAP kinase cascades in the biosynthesis of PGE(2), likely by regulating the induction of cyclo-oxygenase-2, in IL-1beta-stimulated astroglial cells.


Assuntos
Astrócitos/metabolismo , Dinoprostona/biossíntese , Interleucina-1/farmacologia , Isoenzimas/biossíntese , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Proteína Quinase C/fisiologia , Animais , Células Cultivadas , Ciclo-Oxigenase 2 , Indução Enzimática , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno
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