RESUMO
Observations of distant supernovae indicate that the Universe is now in a phase of accelerated expansion the physical cause of which is a mystery. Formally, this requires the inclusion of a term acting as a negative pressure in the equations of cosmic expansion, accounting for about 75 per cent of the total energy density in the Universe. The simplest option for this 'dark energy' corresponds to a 'cosmological constant', perhaps related to the quantum vacuum energy. Physically viable alternatives invoke either the presence of a scalar field with an evolving equation of state, or extensions of general relativity involving higher-order curvature terms or extra dimensions. Although they produce similar expansion rates, different models predict measurable differences in the growth rate of large-scale structure with cosmic time. A fingerprint of this growth is provided by coherent galaxy motions, which introduce a radial anisotropy in the clustering pattern reconstructed by galaxy redshift surveys. Here we report a measurement of this effect at a redshift of 0.8. Using a new survey of more than 10,000 faint galaxies, we measure the anisotropy parameter beta = 0.70 +/- 0.26, which corresponds to a growth rate of structure at that time of f = 0.91 +/- 0.36. This is consistent with the standard cosmological-constant model with low matter density and flat geometry, although the error bars are still too large to distinguish among alternative origins for the accelerated expansion. The correct origin could be determined with a further factor-of-ten increase in the sampled volume at similar redshift.
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To understand the evolution of galaxies, we need to know as accurately as possible how many galaxies were present in the Universe at different epochs. Galaxies in the young Universe have hitherto mainly been identified using their expected optical colours, but this leaves open the possibility that a significant population remains undetected because their colours are the result of a complex mix of stars, gas, dust or active galactic nuclei. Here we report the results of a flux-limited I-band survey of galaxies at look-back times of 9 to 12 billion years. We find 970 galaxies with spectroscopic redshifts between 1.4 and 5. This population is 1.6 to 6.2 times larger than previous estimates, with the difference increasing towards brighter magnitudes. Strong ultraviolet continua (in the rest frame of the galaxies) indicate vigorous star formation rates of more than 10-100 solar masses per year. As a consequence, the cosmic star formation rate representing the volume-averaged production of stars is higher than previously measured at redshifts of 3 to 4.
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Kahweol is a compound derived from coffee with reported antinociceptive effects. Based on the few reports that exist in the literature regarding the mechanisms involved in kahweol-induced peripheral antinociceptive action, this study proposed to investigate the contribution of the endocannabinoid system to the peripheral antinociception induced in rats by kahweol. Hyperalgesia was induced by intraplantar injection of prostaglandin E2(PGE2) and was measured with the paw pressure test. Kahweol and the drugs to test the cannabinoid system were administered locally into the right hind paw. The endocannabinoids were purified by open-bed chromatography on silica and measured by LC-MS. Kahweol (80 µg/paw) induced peripheral antinociception against PGE2-induced hyperalgesia. This effect was reversed by the intraplantar injection of the CB1 cannabinoid receptor antagonist AM251 (20, 40, and 80 µg/paw), but not by the CB2 cannabinoid receptor antagonist AM630 (100 µg/paw). Treatment with the endocannabinoid reuptake inhibitor VDM11 (2.5 µg/paw) intensified the peripheral antinociceptive effect induced by low-dose kahweol (40 µg/paw). The monoacylglycerol lipase (MAGL) inhibitor, JZL184 (4 µg/paw), and the dual MAGL/fatty acid amide hydrolase (FAAH) inhibitor, MAFP (0.5 µg/paw), potentiated the peripheral antinociceptive effect of low-dose kahweol. Furthermore, kahweol increased the levels of the endocannabinoid anandamide, but not of the other endocannabinoid 2-arachidonoylglycerol nor of anandamide-related N-acylethanolamines, in the plantar surface of the rat paw. Our results suggested that kahweol induced peripheral antinociception via anandamide release and activation of CB1 cannabinoid receptors and this compound could be used to develop new drugs for pain relief.
Assuntos
Diterpenos , Endocanabinoides , Analgésicos/farmacologia , Animais , Café , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Ratos , Receptor CB1 de Canabinoide , Receptor CB2 de CanabinoideRESUMO
Extracts from Lychnophora species are traditionally used in Brazil as anti-inflammatory, and to treat bruise, pain and rheumatism. The ethanolic extract of aerial parts of five species of Lychnophoras and one specie of Lychnophoriopsis were examined for the antinociceptive (hot-plate and writhing tests) and anti-inflammatory (carrageenan-induced paw oedema test) activity in mice, by oral and topical routes, respectively. In the hot-plate test, the Lychnophora pinaster (0.75 g/kg) and Lychnophora ericoides (1.50 g/kg) extracts significantly increased the time for licking of the paws. The species Lychnophora passerina, Lychnophoriopsis candelabrum and Lychnophora pinaster, using the dose of 0.75 g/kg, and Lychnophora ericoides and Lychnophora trichocarpha in both doses evaluated (0.75 and 1.50 g/kg) significantly reduced the number of writhes induced by acetic acid. The administration of Lychnophora pinaster and Lychnophora trichocarpha ointments, in both concentrations evaluated (5 and 10%, w/w), and Lychnophora passerina and Lychnophoriopsis candelabrum, in the concentration of 10%, significantly reduced the paw oedema measured 3 h after carrageenan administration, suggesting, for the first time, an anti-inflammatory activity upon topical administration of these species. The present work comparatively demonstrated the antinociceptive and anti-inflammatory activities of some Brazilian Lychnophoras.
Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Asteraceae , Extratos Vegetais/farmacologia , Animais , Feminino , Masculino , CamundongosRESUMO
Kahweol is a compound derived from coffee with reported antinociceptive effects. Based on the few reports that exist in the literature regarding the mechanisms involved in kahweol-induced peripheral antinociceptive action, this study proposed to investigate the contribution of the endocannabinoid system to the peripheral antinociception induced in rats by kahweol. Hyperalgesia was induced by intraplantar injection of prostaglandin E2(PGE2) and was measured with the paw pressure test. Kahweol and the drugs to test the cannabinoid system were administered locally into the right hind paw. The endocannabinoids were purified by open-bed chromatography on silica and measured by LC-MS. Kahweol (80 µg/paw) induced peripheral antinociception against PGE2-induced hyperalgesia. This effect was reversed by the intraplantar injection of the CB1 cannabinoid receptor antagonist AM251 (20, 40, and 80 μg/paw), but not by the CB2 cannabinoid receptor antagonist AM630 (100 μg/paw). Treatment with the endocannabinoid reuptake inhibitor VDM11 (2.5 μg/paw) intensified the peripheral antinociceptive effect induced by low-dose kahweol (40 μg/paw). The monoacylglycerol lipase (MAGL) inhibitor, JZL184 (4 μg/paw), and the dual MAGL/fatty acid amide hydrolase (FAAH) inhibitor, MAFP (0.5 μg/paw), potentiated the peripheral antinociceptive effect of low-dose kahweol. Furthermore, kahweol increased the levels of the endocannabinoid anandamide, but not of the other endocannabinoid 2-arachidonoylglycerol nor of anandamide-related N-acylethanolamines, in the plantar surface of the rat paw. Our results suggested that kahweol induced peripheral antinociception via anandamide release and activation of CB1 cannabinoid receptors and this compound could be used to develop new drugs for pain relief.
RESUMO
A case of discrete subvalvular aortic stenosis with anomalous insertion of a papillary muscle to the base of the anterior mitral valve leaflet and continuous with the discrete subaortic stenosis is described. Two-dimensional echocardiographic and pathologic data showing the contribution of the anomalous papillary muscle to left ventricular outflow tract obstruction are presented.
Assuntos
Estenose Aórtica Subvalvar/patologia , Cardiomiopatia Hipertrófica/patologia , Músculos Papilares/anormalidades , Adulto , Estenose Aórtica Subvalvar/diagnóstico , Cateterismo Cardíaco , Ecocardiografia , Feminino , HumanosRESUMO
This study aimed at evaluating short- and long-term effects of housing beef cattle on deep litter (DL) or concrete fully slatted floor (FS) on their welfare. Animal-based measures of the Welfare Quality® assessment protocol for cattle were used to assess health status and behaviour of bulls. The assessment was carried out in a large commercial farm on 15 batches of bulls (4 DL and 11 FS) 1 month after their receiving day (short-term) and on 12 batches (three DL and nine FS) the week before slaughter (long-term). Signs of better comfort on deep litter in terms of shorter lying down durations (5.1 ± 0.5 v. 6.5 ± 0.4 s; P<0.05) and lower risk of hairless patches (odds ratio=0.09; 95% confidence interval=0.01 to 0.68; P<0.05) were already observed after 1 month. Heavy bulls after a long-term housing on FS showed a higher prevalence of bursitis, hairless patches and lesions/swellings than animals on DL. Bulls on fully slatted floor were at higher risk of early culling (odds ratio=6.44; 95% confidence interval=1.57 to 26.37; P<0.01), mainly due to musculoskeletal system pathologies/lameness. Deep litter proved to be a valid alternative to slatted floor, making animals more confident to interact with powerful movements such as mounting at the end of the finishing period. A negative aspect of the deep litter was the poor cleanliness of the bulls. Compared with the fully slatted floor, there were higher odds ratios for dirty bulls at both, the short- (odds ratio=25.09; 95% confidence interval=8.96 to 70.22; P<0.001) and the long-term housing (odds ratio=276.13; 95% confidence interval=98.21 to 776.38; P<0.001). In order to improve health and welfare of beef cattle finished at a heavy weight, deep litter systems are a promising alternative to fully slatted floors. However, proper management of deep litter is necessary to maintain satisfactory cleanliness of the bulls.
Assuntos
Bem-Estar do Animal , Doenças dos Bovinos/epidemiologia , Pisos e Cobertura de Pisos , Abrigo para Animais , Coxeadura Animal/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/etiologia , Coxeadura Animal/etiologia , MasculinoRESUMO
Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used extensively to control inflammatory pain. Several peripheral antinociceptive mechanisms have been described, such as opioid system and NO/cGMP/KATP pathway activation. There is evidence that the cannabinoid system can also contribute to the in vivo pharmacological effects of ibuprofen and indomethacin. However, there is no evidence of the involvement of the endocannabinoid system in the peripheral antinociception induced by NSAIDs. Thus, the aim of this study was to investigate the participation of the endocannabinoid system in the peripheral antinociceptive effect of NSAIDs. All experiments were performed on male Wistar rats (160-200 g; N = 4 per group). Hyperalgesia was induced by a subcutaneous intraplantar (ipl) injection of prostaglandin E2 (PGE2, 2 µg/paw) in the rat's hindpaw and measured by the paw pressure test 3 h after injection. The weight in grams required to elicit a nociceptive response, paw ï¬exion, was determined as the nociceptive threshold. The hyperalgesia was calculated as the difference between the measurements made before and after PGE2, which induced hyperalgesia (mean = 83.3 ± 4.505 g). AM-251 (80 µg/paw) and AM-630 (100 µg/paw) were used as CB1 and CB2 cannabinoid receptor antagonists, respectively. Ipl injection of 40 µg dipyrone (mean = 5.825 ± 2.842 g), 20 µg diclofenac (mean = 4.825 ± 3.850 g) and 40 µg indomethacin (mean = 6.650 ± 3.611 g) elicited a local peripheral antinociceptive effect. This effect was not antagonized by ipl CB1 cannabinoid antagonist to dipyrone (mean = 5.00 ± 0.9815 g), diclofenac (mean = 2.50 ± 0.8337 g) and indomethacin (mean = 6.650 ± 4.069 g) or CB2 cannabinoid antagonist to dipyrone (mean = 1.050 ± 6.436 g), diclofenac (mean = 6.675 ± 1.368 g) and indomethacin (mean = 2.85 ± 5.01 g). Thus, cannabinoid receptors do not seem to be involved in the peripheral antinociceptive mechanism of the NSAIDs dipyrone, diclofenac and indomethacin.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Nociceptividade/efeitos dos fármacos , Receptor CB1 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/agonistas , Animais , Endocanabinoides/antagonistas & inibidores , Endocanabinoides/farmacologia , Masculino , Medição da Dor , Ratos Wistar , Receptor CB1 de Canabinoide/fisiologia , Receptor CB2 de Canabinoide/fisiologiaRESUMO
Nonsteroidal anti-inflammatory drugs (NSAIDs) have been used extensively to control inflammatory pain. Several peripheral antinociceptive mechanisms have been described, such as opioid system and NO/cGMP/KATP pathway activation. There is evidence that the cannabinoid system can also contribute to the in vivo pharmacological effects of ibuprofen and indomethacin. However, there is no evidence of the involvement of the endocannabinoid system in the peripheral antinociception induced by NSAIDs. Thus, the aim of this study was to investigate the participation of the endocannabinoid system in the peripheral antinociceptive effect of NSAIDs. All experiments were performed on male Wistar rats (160-200 g; N = 4 per group). Hyperalgesia was induced by a subcutaneous intraplantar (ipl) injection of prostaglandin E2 (PGE2, 2 μg/paw) in the rat’s hindpaw and measured by the paw pressure test 3 h after injection. The weight in grams required to elicit a nociceptive response, paw flexion, was determined as the nociceptive threshold. The hyperalgesia was calculated as the difference between the measurements made before and after PGE2, which induced hyperalgesia (mean = 83.3 ± 4.505 g). AM-251 (80 μg/paw) and AM-630 (100 μg/paw) were used as CB1 and CB2 cannabinoid receptor antagonists, respectively. Ipl injection of 40 μg dipyrone (mean = 5.825 ± 2.842 g), 20 μg diclofenac (mean = 4.825 ± 3.850 g) and 40 μg indomethacin (mean = 6.650 ± 3.611 g) elicited a local peripheral antinociceptive effect. This effect was not antagonized by ipl CB1 cannabinoid antagonist to dipyrone (mean = 5.00 ± 0.9815 g), diclofenac (mean = 2.50 ± 0.8337 g) and indomethacin (mean = 6.650 ± 4.069 g) or CB2 cannabinoid antagonist to dipyrone (mean = 1.050 ± 6.436 g), diclofenac (mean = 6.675 ± 1.368 g) and indomethacin (mean = 2.85 ± 5.01 g). Thus, cannabinoid receptors do not seem to be involved in the peripheral antinociceptive mechanism of the NSAIDs dipyrone, diclofenac and indomethacin.
Assuntos
Animais , Masculino , Anti-Inflamatórios não Esteroides/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Nociceptividade/efeitos dos fármacos , Receptor CB1 de Canabinoide/agonistas , /agonistas , Endocanabinoides/antagonistas & inibidores , Endocanabinoides/farmacologia , Medição da Dor , Ratos Wistar , Receptor CB1 de Canabinoide/fisiologia , /fisiologiaRESUMO
O presente estudo teve como objetivo uma citotoxicidade sobre Artemia salina de vinhos e dois extratos de cinco espécies do gênero Lychnophora e de uma espécie de Lychnophoriopsis . Os extratos solubilizados em DMSO, preparados nas concentrações finais de 100, 250, 375, 500 e 600 µg mL -1 , foram adicionados a recipientes contendo náuplios de Artemia salina (10 unidades cada) e completo em volume para 5 mL de solução marinha. Lapachol e DMSO 5% foram como controles positivo e negativo, respectivamente. Como amostras foram mantidas sob iluminação e como larvas mortas foram contadas após 24 horas de contato. O cálculo da LC 50 foi feito com o programa Probitos. Os extratos brutos etanólicos de cinco Espécies apresentaram baixa letalidade nd Seguinte Ordem: Lychnophora trichocarpha (LC 50 = 672,38 ng mL -1 )> Lychnophora pinaster (LC 50 = 678,73 ng mL -1 )> Lychnophora ericoides (LC 50 = 738,09 µg mL -1 )> Lycellophoriopsis candelabro (LC 50 = 812,57 µg mL -1 )> Lychnophora passerina (LC 50 = 921,78 µg mL -1 ). Todos os extratos testados de Lychnophoriopsis candelabro eo extrato clorofórmico de Lychnophora staavioides mostraram leve toxicidade sobre A. salina . Os resultados indicaram que existem substâncias com potencial atividade farmacológica em todas as espécies testadas.
The present study aimed to evaluate on Artemia salina the citotoxicity of twenty-two extracts from five species of the genus Lychnophora and one species of the genus Lychnophoriopsis. The extracts solubilized in DMSO and prepared at the final concentrations of 100, 250, 375, 500 and 600 ïg mL-1 were added to tubes containing Artemia salina nauplii (10 units each) and filled to 5 mL total volume with artificial salt water. Lapachol and 5% DMSO were used as positive and negative controls, respectively. The samples were kept under light and dead larvae were counted after 24 hours of contact. LC50 was calculated by using Probit software. The crude ethanol extracts from five species showed low lethality in the following order: Lychnophora trichocarpha (LC50 = 672.38 ïg mL-1) > Lychnophora pinaster (LC50 = 678.73 ïg mL-1) > Lychnophora ericoides (LC50 = 738.09 ïg mL-1) > Lychnophoriopsis candelabrum (LC50 = 812.57 ïg mL-1) > Lychnophora passerina (LC50 = 921.78 ïg mL-1). All tested extracts from L. candelabrum and chloroform extract from L. staavioides showed light toxicity on A. salina. Results indicated that there are substances with potential pharmacological activity in all tested species
Assuntos
Artemia/classificação , Bioensaio/instrumentação , Asteraceae/classificaçãoRESUMO
Clusters of galaxies are visible tracers of the network of matter in the Universe, marking the high-density regions where filaments of dark matter join together. When observed at X-ray wavelengths these clusters shine like cosmic lighthouses, as a consequence of the hot gas trapped within their gravitational potential wells. The X-ray emission is linked directly to the total mass of a cluster, and so can be used to investigate the mass distribution for a sizeable fraction of the Universe. The picture that has emerged from recent studies is remarkably consistent with the predictions for a low-density Universe dominated by cold dark matter.
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Reference is made to results obtained at the University of Messina Anaesthesiology and Resuscitation department with an "Emoadsorb" haemodepurator set in 18 patients with serious exogenous toxicosis. The criteria used in the indication of this treatment include the seriousness of the clinical picture and quantitative and qualitative assessment of the poison in the blood. A key feature of the system used was a highly biocompatible, hydroxyethylmetacrylate membrane coating the activated carbon, capable of subtracting toxins in a 300-5000 p.m. range. The effectiveness of the method was appraised clinically and by gas chromatography, to quantify the amount of poison in the blood before and after treatment. Rapid detoxication was obtained in 16/18 cases. It is therefore felt that extracorporeal haemodepuration with A.C. is a sound form of management in cases of acute exogenous toxicosis, and should be more widely employed in resuscitation departments.