of the balance between water inputs (precipitation and/or irrigation) and losses through evapotranspiration (ET), and has been used to examine the effects of climatic variability on terrestrial systems (Kahmen et al., 2011; Sternberg, 2009). Although extensively used in living plants (e.g., tree rings), the analysis of cellulose is limited by its typically short life after decomposition of plant biomass. Under particular conditions, cellulose extracted from fossil plants have been used to produce climate records that go back millions of years (Jahren and Sternberg, 2003), but such well-preserved samples are rare. In contrast to cellulose, plantderived lipids can persist in soils and sediments due to their low biodegradability and stabilisation into hydrophobic domains of organic matter (Matsumoto et al., 2007; Assis et al., 2011), providing a potential long-term record of terrestrial water balance. Plant lipids may be broadly defined as hydrophobic or amphiphilic molecules originating entirely or in part from two types of biochemical subunits, ketoacyl and isoprene groups, which are building blocks for molecules of various structures and polarities, including some with no oxygen at all (e.g., alkanes in leaf surface wax) and others that carry various amount of oxygen (Fahy et al., 2009). The value of lipid hydrogen isotope analysis (δ 2 H) has already been recognised for specific compounds recovered from soils and sediments (Sachse et al., 2012). The study of lipid δ 18 O signals has the potential to improve δ 2 H records by, for example, allowing water loss to be partitioned into evaporation and transpiration (Voelker et al., 2014). The first step towards the use of lipid δ 18 O records is to demonstrate that a signal related to changes in water balance is recorded in such compounds. The second step is then to demonstrate that this signal is preserved in soils and sediments. The present study is concerned with the first step. However, without losing sight of the second step, we imposed the restriction that lipid extracts should contain only the most apolar compounds present in the plant biomass, under the assumption that these are also the most likely to persist after deposition (Matsumoto et al., 2007). To advance the interpretation of lipid δ 18 O signals, we compared measurements of cellulose and hexane-extractable compounds of C 3 and C 4 species, grown under contrasting water regimes in replicated field experiments. In addition, we analysed the carbon isotope composition (δ 13 C) of cellulose and lipids as a way to assess plant water-use efficiency (Farquhar and Von Caemmerer, 1982). Alongside these isotopic measurements, we used spectroscopic analyses to qualitatively describe the molecular composition of lipid extracts and all results are integrated into a consideration of potential applications in ancient and contemporary settings. Methods Field Experiment. The field experiment was conducted at the University of California Five Points Experimental Station (36°20'10.28"N, 120°6'38.40"W). This site experie...
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.
RESUMO:Objetivou-se investigar o efeito do extrato acetato de etila de Cocos nucifera (EAECN) sobre parâmetros fisiológicos e sobre a inflamação tópica induzida por xileno. EAECN foi obtido a partir da água da fibra da casca do coco verde e o teste fitoquímico indicou a presença de taninos condensados, flavononas, flavonóis, flavononóis, xantonas e esteróides. EAECN foi administrado aos camundongos Swiss por via oral em dose única diária de 10, 30, 100 e 250 mg Kg -1 por cinco dias consecutivos para os protocolos de toxicidade e inflamação tópica. No ensaio de toxicidade foram observadas as freqüências cardíacas e respiratórias, a presença de diarréia, analgesia e apatia e realizada a contagem total dos leucócitos do sangue periférico, avaliação macroscópica dos órgãos e peso relativo do rim, fígado, timo e baço. O efeito do EAECN sobre a inflamação tópica foi realizado utilizando-se grupos testes com as diferentes concentrações de EAECN e grupos controles positivos que receberam, pela mesma via nas mesmas condições, NaCl 0,9% ou DMSO a 5% ou o antiinflamatório padrão, Dexametasona (6 mg Kg -1 ). Todos os animais receberam o agente flogístico (25 L) nas partes interna e externa da orelha duas horas após o último tratamento, enquanto os animais do grupo controle negativo não receberam qualquer tratamento. Após 50 minutos da aplicação do xileno, os animais foram sacrificados, e uma porção de cada orelha foi retirada e pesada. A diferença de peso entre as orelhas representa o efeito induzido pelos tratamentos. EAECN não desenvolveu toxicidade, não alterou a contagem total de leucócitos, não alterou o peso e nem o peso relativo dos órgãos dos animais tratados em relação aos controles. EAECN não inibiu a inflamação provocada pelo xileno, apresentando efeito pró-inflamatório dependente da dose. Conclui-se que EAECN nos protocolos utilizados não é tóxico e não possui atividade antiinflamatória tópica. Palavras-chave:Cocus nucifera, xileno, Inflamação tópica, toxicidade, parâmetros fisiológicos ABSTRACT: Toxicological evaluation and effect of ethyl acetate extract of the fiber of Cocos nucifera L. (Palmae) on inflammatory response in vivo. This study aimed to investigate the effect of ethyl acetate extract of Cocos nucifera (EAECN) on physiological parameters and xylene-induced topic inflammation. EAECN was obtained from the water of the green coconut husk fiber and the phytochemical test indicated the presence of condensed tannins, flavanones, flavonols, xanthones and steroids. EAECN was orally administered to Swiss mice at a single daily dose of 10, 30, 100 and 250 mg Kg -1 during five consecutive days for toxicity and topic inflammation protocols. Toxicity experiments included the observation of heart and respiratory frequencies, diarrhea, analgesia and apathy, besides total leukocyte count in peripheral blood, macroscopic evaluation of the organs, and relative weight of kidneys, liver, thymus and spleen. The effect of EAECN on topic inflammation was assessed using test groups with different EAECN concentrations and...
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