994 resultados para cis-andean
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The title compound, C(13)H(9)F(3)N(2)O(2)S, crystallizes with two independent molecules in the asymmetric unit. The central thiourea core is roughly coplanar with the furan and benzene rings, showing O-C-N-C(S) torsion angles of 2.3 (4) and -11.4 (2) degrees and (S) C -N-C-C torsion angles of -2.4 (4) and -28.8 (4) degrees, respectively, in the two independent molecules. The trans-cis geometry of the thiourea fragment is stabilized by an intramolecular N-H center dot center dot center dot O hydrogen bond between the H atom of the cis thioamide and the carbonyl O atom. In the crystal structure, intermolecular N-H center dot center dot center dot S hydrogen bonds form centrosymmetric dimers extending along the b axis.
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In the title compound, C(16)H(12)N(2)O(2)S, the carbonylthiourea group forms dihedral angles of 75.4 (1) and 13.1 (2)degrees, respectively, with the naphthalene ring system and furan ring. The molecule adopts a trans-cis configuration with respect to the positions of the furoyl and naphthyl groups relative to the S atom across the thiourea C-N bonds. This geometry is stabilized by an N-H center dot center dot center dot center dot O intramolecular hydrogen bond. In the crystal structure, molecules are linked by N-H center dot center dot center dot S hydrogen bonds, forming centrosymmetric dimers which are interlinked through C-H center dot center dot center dot pi interactions.
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Concentrations of cations (Na(+), Ca(2+), Mg(2+), K(+), NH(4) (+)), anions (HCO(3) (-), Cl(-), NO(3) (-), SO(4) (2-), PO(4) (3-)) and suspended sediments in the Madeira River water were determined near the city of Porto Velho (RO), in order to assess variation in water chemistry from 2004 to 2007. Calcium and bicarbonate were the dominant cation and anion, respectively. Significant seasonal differences were found, with highest concentrations occurring during the dry season, as expected from the drainage of Andean carbonate-rich substratum. Interannual variations were also observed, but became significant only when annual average discharge was 25% less than normal. Under this atypical discharge condition, bicarbonate was replaced by sulfate, and higher suspended sediment concentrations and loads were also observed. Compared to previously published studies, it appears that no significant changes in water chemistry have occurred during the last 20-30 years, although differences in approaches and sampling designs among this and previous studies may not allow detection of modest changes. The calculated suspended sediment load reported here is close to the values presented elsewhere, reinforcing the relative importance of this river as a sediment supplier for the Amazon Basin. Seasonality has a significant control on the chemistry of Madeira River waters, and severe decrease in discharge due to anthropogenic changes, such as construction of reservoirs or the occurrence of drier years-a plausible consequence of global climate change-may lead to modification in the chemical composition as well in the sediment deliver to the Amazon River.
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The objectives of this study were to characterise four essential oils (EO) chemically and to evaluate their effect on ruminal fermentation and methane emission in vitro. The investigated EO were isolated from Achillea santolina, Artemisia judaica, Schinus terebinthifolius and Mentha microphylla, and supplemented at four levels (0, 25, 50 and 75 l) to 75ml of buffered rumen fluid plus 0.5 g of substrate. The main components of the EO were piperitone (49.1%) and camphor (34.5%) in A. judaica, 16-dimethyl 15-cyclooactdaiene (60.5%) in A. santolina, piperitone oxide (46.7%) and cis-piperitone oxide (28%) in M. microphylla, and -muurolene (45.3%) and -thujene (16.0%) in S. terebinthifolius. The EO from A. santolina (at 25 and 50 l), and all levels of A. judaica increased the gas production significantly, but S. terebinthifolius (at 50 and 75 l), A. santolina (at 75 l) and all levels of M. microphylla decreased the gas production significantly in comparison with the control. The highest levels of A. santolina and A. judaica, and all doses from M. microphylla EO inhibited the methane production along with a significant reduction in true degradation of dry matter and organic matter, protozoa count and NH3-N concentration. It is concluded that the evaluated EO have the potential to affect ruminal fermentation efficiency and the EO from M. microphylla could be a promising methane mitigating agent.
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de Souza Jr, TP, Fleck, SJ, Simao, R, Dubas, JP, Pereira, B, de Brito Pacheco, EM, da Silva, AC, and de Oliveira, PR. Comparison between constant and decreasing rest intervals: influence on maximal strength and hypertrophy. J Strength Cond Res 24(7): 1843-1850, 2010-Most resistance training programs use constant rest period lengths between sets and exercises, but some programs use decreasing rest period lengths as training progresses. The aim of this study was to compare the effect on strength and hypertrophy of 8 weeks of resistance training using constant rest intervals (CIs) and decreasing rest intervals (DIs) between sets and exercises. Twenty young men recreationally trained in strength training were randomly assigned to either a CI or DI training group. During the first 2 weeks of training, 3 sets of 10-12 repetition maximum (RM) with 2-minute rest intervals between sets and exercises were performed by both groups. During the next 6 weeks of training, the CI group trained using 2 minutes between sets and exercises (4 sets of 8-10RM), and the DI group trained with DIs (2 minutes decreasing to 30 seconds) as the 6 weeks of training progressed (4 sets of 8-10RM). Total training volume of the bench press and squat were significantly lower for the DI compared to the CI group (bench press 9.4%, squat 13.9%) and weekly training volume of these same exercises was lower in the DI group from weeks 6 to 8 of training. Strength (1RM) in the bench press and squat, knee extensor and flexor isokinetic measures of peak torque, and muscle cross-sectional area (CSA) using magnetic resonance imaging were assessed pretraining and posttraining. No significant differences (p <= 0.05) were shown between the CI and DI training protocols for CSA (arm 13.8 vs. 14.5%, thigh 16.6 vs. 16.3%), 1RM (bench press 28 vs. 37%, squat 34 vs. 34%), and isokinetic peak torque. In conclusion, the results indicate that a training protocol with DI is just as effective as a CI protocol over short training periods (6 weeks) for increasing maximal strength and muscle CSA; thus, either type of program can be used over a short training period to cause strength and hypertrophy.
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An analysis of geomorphic system`s response to change in human and natural drivers in some areas within the Rio de la Plata basin is presented The aim is to determine whether an acceleration of geomorphic processes has taken place in recent years and, if so, to what extent it is due to natural (climate) or human (land-use) drivers Study areas of different size, socio-economic and geomorphic conditions have been selected: the Rio de la Plata estuary and three sub-basins within its watershed Sediment cores were extracted and dated ((210)Pb) to determine sedimentation rates since the end of the 19th century. Rates were compared with time series on rainfall as well as human drivers such as population, GDP, livestock load, crop area, energy consumption or cement consumption, all of them related to human capacity to disturb land surface Data on river discharge were also gathered Results obtained indicate that sedimentation rates during the last century have remained essentially constant in a remote Andean basin, whereas they show important increases in the other two, particularly one located by the Sao Paulo metropolitan area Rates in the estuary are somewhere in between It appears that there is an intensification of denudation/sedimentation processes within the basin. Rainfall remained stable or varied very slightly during the period analysed and does not seem to explain increases of sedimentation rates observed. Human drivers, particularly those more directly related to capacity to disturb land surface (GDP, energy or cement consumption) show variations that suggest human forcing is a more likely explanation for the observed change in geomorphic processes It appears that a marked increase in denudation, of a ""technological"" nature, is taking place in this basin and leading to an acceleration of sediment supply This is coherent with similar increases observed in other regions (C) 2010 Elsevier B V All rights reserved
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We describe in this paper a new genus and species of cricetid rodent from the Atlantic Forest of Brazil, one of the most endangered eco-regions of the world. The new form displays some but not all synapomorphies of the tribe Oryzomyini, but a suite of unique characteristics is also observed. This new forest rat possesses anatomical characteristics of arboreal taxa, such as very developed plantar pads, but was collected almost exclusively in pitfall traps. Phylogenetic analyses of morphological (integument, soft tissue, cranial, and dental characters) and molecular [nuclear - Interphotoreceptor retinoid binding protein (Irbp) - and mitochondrial - cytochrome b - genes] datasets using maximum likelihood and cladistic parsimony approaches corroborate the inclusion of the new taxon within oryzomyines. The analyses also place the new form as sister species to Eremoryzomys polius, an Andean rat endemic to the Maranon valley. This biogeographical pattern is unusual amongst small terrestrial vertebrates, as a review of the literature points to few other similar examples of Andean-Atlantic Forest pairings, in hylid frogs, Pionus parrots, and other sigmodontine rodents. (C) 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161, 357-390. doi:10.1111/j.1096-3642.2010.00643.x
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Conjugated linoleic acids (CLA) are potent anticarcinogens in animal and in vitro models as well as inhibitors of fatty acid synthesis in mammary gland, liver, and adipose tissue. Our objective was to evaluate long-term CLA supplementation of lactating dairy cows in tropical pasture on milk production and composition and residual effects posttreatment. Thirty crossbred cows grazing stargrass (Cynodon nlemfuensis Vanderyst var. nlemfuensis) were blocked by parity and received 150 g/d of a dietary fat supplement of either Ca-salts of palm oil fatty acids (control) or a mixture of Ca-salts of CLA (CLA treatment). Supplements of fatty acids were mixed with 4 kg/d of concentrate. Grazing plus supplements were estimated to provide 115% of the estimated metabolizable protein requirements from 28 to 84 d in milk (treatment period). The CLA supplement provided 15 g/d of cis-9, trans-11 and 22 g of cis-10, trans-12. Residual effects were evaluated from 85 to 112 d in milk (residual period) when cows were fed an 18% crude protein concentrate without added fat. The CLA treatment increased milk production but reduced milk fat concentration from 2.90 to 2.14% and fat production from 437 to 348 g/d. Milk protein concentration increased by 11.5% (2.79 to 3.11%) and production by 19% (422 to 504 g/d) in the cows fed CLA. The CLA treatment decreased milk energy concentration and increased milk volume, resulting in unchanged energy output. Milk production and protein concentration and production were also greater during the residual period for the CLA-treated cows. The CLA treatment reduced production of fatty acids (FA) of all chain lengths, but the larger effect was on short-chain FA, causing a shift toward a greater content of longer chain FA. The CLA treatment increased total milk CLA content by 30% and content of the trans-10, cis-12 CLA isomer by 88%. The CLA treatment tended to decrease the number of days open, suggesting a possible effect on reproduction. Under tropical grazing conditions, in a nutritionally challenging environment, CLA-treated cows decreased milk fat content and secreted the same amount of milk energy by increasing milk volume and milk protein production.
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The objective of this study was to evaluate the effects of dietary addition of ground oilseed sources on the quality, fatty acid profile, and CLA content of meat from zebu steers. Thirty-one zebu steers with an initial average age of 23 mo and an initial BW of 365 kg were used in this study. The experimental period was 84 d, which was preceded by an adaption period of 28 d. The diet was provided ad libitum with a forage: concentrate ratio of 40:60. Corn silage was used as the forage source. Four different concentrates were formulated for each treatment: without additional lipids (control) or with ground soybeans (SB), ground cottonseed (CS), or ground linseed (LS). The SB, CS, and LS diets were formulated to have 6.5% ether extract on a total dietary DM basis. The experiment was set up as a completely randomized design. After slaughter, samples were taken from the longissimus thoracis muscle for the measurement of fatty acid concentration and the evaluation of meat quality. The luminosity index was greater in the control and LS diets (P < 0.01). The greatest percentages of myristic acid (C14:0), palmitic acid (C16:0), trans octadecenoic acid (C18:1 trans-10, trans-11, or trans-12), and SFA in the subcutaneous fat were observed in the CS treatment (P < 0.01). Moreover, the least percentages of oleic acid (C18:1 cis-9) and total unsaturated fatty acids in the subcutaneous fat were observed in the CS diet (P < 0.01). The meat linoleic acid and a-linolenic acid percentages were greatest in the SB and LS treatments, respectively (P < 0.001). The unsaturated fatty acid: SFA ratio was smallest for the CS diet (P < 0.01). A gradual increase in oxidation was observed as a function of storage time; however, the diets did not affect the rancidity of the meat (P > 0.05). The fatty acid profile of subcutaneous fat was impaired by the addition of CS. Supplying ground oilseeds did not increase the content of CLA in the meat.
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This experiment was designed to examine changes in milk fatty acids during fish oil-induced milk fat depression (MFD) and to test the theory that these changes are related to milk fat fluidity. The experiment was divided into three periods: 1) Baseline: all cows (n = 12) received a high fiber diet without fish oil (FO) for 12 days; 2) Treatment: 4 cows/group received the following treatments for 21 days: a) Low fiber diet without FO (LF), b) High fiber diet+FO (HF+FO) and c) Low fiber diet+FO (LF+FO); 3) Post-treatment: cows returned to the baseline diet and were monitored for 12 days. FO was included at 1.6% DM and HF and LF diets had 40 and 26% NDF, respectively. Milk fat content and yield were unchanged by the LF diet, but were reduced by FO diets at both dietary fiber levels and recovered in the post-treatment period. FO diets caused a pronounced reduction in stearic and oleic acid concentrations in milk fat and an equally pronounced increase in trans-18:1 fatty acid concentrations. Milk fat mean melting point (MMP) was correlated with MFD (r=0.73) and with milk oleic acid concentration (r=-0.92). The ratio of oleic:stearic in milk fat increased gradually and consistently in response to FO. Trans-C18:1 isomers with double bounds at carbon :<= 10 increased with greater MFD and those with double bonds at carbon ! I I decreased with greater MFD. Trans-9 cis-11 CLA explained more than 80% of MFD and was strongly correlated with trans-10 C18:1. Maintenance of MMP below 39-40 degrees C suggests that the mammary gland was able to secrete only milk fat with adequate fluidity and that MFD could be an adaptation mechanism to prevent secretion of milk with higher MMP. (C) 2007 Elsevier B.V. All rights reserved.
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Seed coats, cotyledons and hypocotyls from six Peruvian (Lupinus mutabilis Sweet) and two Brazilian (Lupinus albus and Lupinus angustifolius) lupin cultivars were assessed regarding their content of isoflavones and antioxidant capacity. Genistein and a genistein derivative were detected in seed coats and cotyledons from Peruvian cultivars. Total isoflavones ranged from 9.8 to 87, 16.1 to 30.8 and 1.3 to 6.1 mg/100 g of sample in fresh weight (expressed as genistein) in seed coat, cotyledon and hypocotyl fractions, respectively, from mutabilis species, whereas no isoflavones were detected in L. angustifolius and L. albus. A significant correlation (r = 0.99) was found between the total isoflavone levels and the antioxidant capacity measured by the 2,2-diphenyl-1-picrylhydrazyl radical-scavenging method in all fractions of Peruvian samples. No condensed tannins were detected in any of the lupin cultivars. The H-6 Andean cultivar is promising for its high isoflavone content and antioxidant capacity. Insights from this study indicate that lupin cultivars of the mutabilis species have similar isoflavone profiles and that isoflavones are more concentrated in the cotyledon seed fraction than in the seed coat or hypocotyl fractions. (C) 2008 Elsevier Inc. All rights reserved.
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Background: Tramadol is a well tolerated and effective analgesic used to treat moderate to severe pain. Several generic formulations of tramadol are available in Brazil; however, published information regarding their bioequivalence in the Brazilian population is not available. A study was designed for Brazilian regulatory authorities to allow marketing of a generic formulation. Objective: The purpose of this study was to compare the bioequivalence of 2 commercial tablet preparations containing tramadol 100 mg marketed for use in Brazil. Methods: A randomized, open-label, 2 x 2 crossover study was performed in healthy Brazilian volunteers under fasting conditions with a washout period of 12 days. Two tablet formulations of tramadol 100 mg (test and reference formulations) were administered as a single oral dose, and blood samples were collected over 24 hours. Tramadol plasma concentrations were quantified using a validated HPLC method. A plasma concentration time profile was generated for each volunteer and then mean values were determined, from which C(max), T(max), AUC(0-t), AUC(0-infinity), k(e), and t(1/2) were calculated using a noncompartmental model. Bioequivalence between the products was determined by calculating 90% CIs for the ratios of C(max), AUC(0-t), and AUC(0-infinity) values for the test and reference products using log-transformed data. Tolerability was assessed by monitoring vital signs (temperature, blood pressure, heart rate), laboratory tests (hematology, blood biochemistry, hepatic function, urinalysis), and interviews with the volunteers before medication administration and every 2 hours during the study. Results: Twenty-six healthy volunteers (13 men, 13 women) were enrolled in and completed the study. Mean (SD) age was 30 (6.8) years (range, 21-44 years), mean weight was 64 (8.3) kg (range, 53-79 kg), and mean height was 166 (6.4) cm (range, 155-178 cm). The 90% CIs for the ratios of C(max) (1.01-1.17), AUC(0-t) (1.00-1.13), and AUC(0-infinity) (1.00-1.14) values for the test and reference products fell within the interval of 0.80 to 1.25 proposed by most regulatory agencies, including the Brazilian regulatory body. No clinically important adverse effects were reported; only mild somnolence was reported by 4 volunteers and mild headaches by 5 volunteers, and there was no need to use medication to treat these symptoms. Conclusion: Pharmacokinetic analysis in these healthy Brazilian volunteers suggested that the test and reference formulations of tramadol 100-mg tablets met the regulatory requirements to assume bio-equivalence based on the Brazilian regulatory definition. (Clin Ther 2010;32:758-765) (C) 2010 Excerpta Medica Inc.
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This work is focused on the influence of dilution rate (0.08 <= D <= 0.32 d(1)) on the continuous cultivation and biomass composition of Arthrospira (Spirulina) platensis using three different concentrations of ammonium chloride (c(No) = 1.0, 5.0 and 10 mol m (3)) as nitrogen source. At c(No) = 1.0 and 5.0 mol m (3) the biomass protein content was an increasing function of D, whereas, when using c(No) = 10 mol m (3), the highest protein content (72.5%) was obtained at D = 0.12 d (1). An overall evaluation of the process showed that biomass protein content increased with the rate of nitrogen supply (D c(No)) up to 72.5% at D c(No) = 1.20 mol m (3) d (1). Biomass lipid content was an increasing function of D only when the nitrogen source was the limiting factor for the growth (D c(No) <= 0.32 mol m (-3) d (1)), which occurred solely with c(No), = 1.0 mol m (3). Under such conditions, A. platensis reduced its nitrogen reserve in the form of proteins, while maintaining almost unvaried its lipid content. The latter was affected only when the concentration of nitrogen was extremely low (c(No) = 1.0 mol m (3)). The most abundant fatty acids were the palmitic (45.8 +/- 5.20%) and the gamma-linolenic (20.1 +/- 2.00%) ones. No significant alteration in the profiles either of saturated or unsaturated fatty acids was observed with c(No) <= 5.0 mol m (3), prevailing those with 16 and 18 carbons. (C) 2010 Elsevier Ltd. All rights reserved.
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Background: Zidovudine is a thymidine nucleoside reverse transcriptase inhibitor with activity against HIV type 1. Some (similar to 8) generic formulations of zidovudine are available in Brazil; however, based on a literature search, information concerning their bioavailability and pharmacokinetic properties in the Brazilian population has not been reported. Objective: The aim of this study was to compare the bioavailability and pharmacokinetic properties of 2 capsule formulations of zidovudine 100 mg in healthy Brazilian volunteers. Methods: This open-label, randomized, 2-way crossover study utilized a 1-week washout period between doses. Blood samples were collected for 8 hours after a single dose of zidovudine 100-mg test (Zidovudina, Fundaqdo para o Remedio Popular, Sao Paulo, Brazil) or reference formulation (Retrovir (R), GlaxoSmithKline, Philadelphia, Pennsylvania). Plasma zidovudine concentrations were determined using a validated high-performance liquid chromatography method with ultraviolet detection at 265 nm. C-max, T-max, AUC(0-t), AUC(0-infinity), t(1/2), and the elimination constant (k(e)) were determined using noncompartmental analysis. The formulations were considered bioequivalent if the 90% CIS for C-max, AUC(0-t), and AUC(0-infinity) fell within the interval of 80 % to 125 %, the regulatory definition set by the US Food and Drug Administration (FDA). Results: Twenty-four healthy volunteers (12 males, 12 females; mean age, 27 years; weight, 60 kg; height, 167 cm) were enrolled and completed the study. The 90% CIs of the treatment ratios for the logarithmic-transformed values of C-max, AUC(0-t), and AUC(0-infinity) were 80.0% to 113.6%, 93.9% to 109.7%, and 93.6% to 110.1 %, respectively. The values for the test and reference formulations were within the FDA bioequivalence definition intervals of 80% to 125%. Conclusions: In this small study in healthy subjects, no statistically significant differences in C-max, AUC(0-t), and AUC(0-)infinity were found between the test and reference formulations of zidovudine 100-mg capsules. The 90% CIs for the mean ratio values for the test and reference formulations of AUC(0-t), AUC(0-infinity), and C-max indicated that the reported data were entirely within the bioequivalence acceptance range proposed by the FDA of 80% to 125% (using log-transformed data).
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Background and purpose: The contribution of endothelin-1 (ET-1) to vascular hyper-reactivity associated with chronic ethanol intake, a major risk factor in several cardiovascular diseases, remains to be investigated. Experimental approach: The biphasic haemodynamic responses to ET-1 (0.01-0.1 nmol kg(-1), i.v.) or to the selective ET(B) agonist, IRL1620 (0.001-1.0 nmol kg(-1), i.v.), with or without ET(A) or ET(B) antagonists (BQ123 (c(DTrp-Dasp-Pro-Dval-Leu)) at 1 and 2.5 mg kg(-1) and BQ788 (N-cis-2,6-dimethyl-piperidinocarbonyl-L-gamma-methylleucyl1-D-1methoxycarbonyltryptophanyl-D-norleucine) at 0.25 mg kg(-1), respectively) were tested in anaesthetized rats, after 2 weeks` chronic ethanol treatment. Hepatic parameters and ET receptor protein levels were also determined. Key results: The initial hypotensive responses to ET-1 or IRL1620 were unaffected by chronic ethanol intake, whereas the subsequent pressor effects induced by ET-1, but not by IRL1620, were potentiated. BQ123 at 2.5 but not 1 mg kg(-1) reduced the pressor responses to ET-1 in ethanol-treated rats. Conversely, BQ788 (0.25 mg kg(-1)) potentiated ET-1-induced increases in mean arterial blood pressure in control as well as in ethanol-treated rats. Interestingly, in the latter group, increases in heart rate, induced by ET-1 at a dose of 0.025 mg kg(-1) were enhanced following ET(B) receptor blockade. Finally, we observed higher levels of ET(A) receptor in the heart and mesenteric artery and a reduction of ET(B) receptor protein levels in the aorta and kidney from rats chronically treated with ethanol. Conclusions and implications: Increased vascular reactivity to ET-1 and altered protein levels of ET(A) and ET(B) receptors could play a role in the pathogenesis of cardiovascular complications associated with chronic ethanol consumption.