Reclamation status of a degraded pasture based on soil health indicators

Pasture degradation is a concern, especially in susceptible sandy soils for which strategies to recover them must be developed. Microbiological and biochemical soil health indicators are useful in the guindace of soil management practices and sustainable soil use. We assessed the success of threePanicum maximum Jacq. cultivars in the reclamation of a pasture in a sandy Typic Acrudox in the northwest of the state of Paraná, Brazil, based on soil health indicators. On a formerly degraded pasture withUrochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, a trial with threeP. maximum (cv. Massai, Tanzânia, or Mombaça) was conducted. Lime and phosphate were applied at set-up, and mineral N and K as topdressing. A remnant of degraded pasture adjacent to the trial was used as control. Twenty-three chemical, physical, microbiological and biochemical attributes were assessed for the 0-10 cm topsoil. The procedures for reclamation improved most of the indicators of soil health in relation to the degraded pasture, such as soil P, mineral N, microbial biomass C, ammonification rate, dehydrogenase activity and acid phosphatase. CO2 evolution decreased, whereas microbial biomass C increased in the pasture under reclamation, resulting in a lower metabolic quotient (qCO2) that points to a decrease in metabolic stress of the microbial community. The reclamation of the pasture withP. maximum, especially cv. Mombaça, were evidenced by improvements in the microbiological and biochemical soil health indicators, showing a recovery of processes related to C, N and P cycling in the soil

Simvastatin Inducing Pc3 Prostate Cancer Cell Necrosis Mediated By Calcineurin And Mitochondrial Dysfunction

In the present study we analyzed the mechanisms of simvastatin toxicity for the PC3 human prostate cancer cell line. At 10 μM, simvastatin induced principally apoptosis, which was prevented by mevalonic acid but not by cyclosporin A, the inhibitor of calcineurin and mitochondrial permeability transition (MPT). At 60 μM, simvastatin induced the necrosis of PC3 cells insensitive to mevalonic acid. Cell necrosis was preceded by a threefold increase in cytosolic free Ca 2+ concentration and a significant decrease in both respiration rate and mitochondrial membrane potential. Both mitochondrial dysfunction and necrosis were sensitive to the compounds cyclosporin A and bongkrekic acid, as well as the calcineurin inhibitor FK506. We have concluded that simvastatin-induced PC3 cells apoptosis is dependent on 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibition and independent of MPT, whereas necrosis is dependent on mitochondrial dysfunction caused, at least in part, by calcineurin. © 2008 Springer Science+Business Media, LLC.404307314Almeida, S., Domingues, A., Rodrigues, L., (2004) Neurobiol Dis, 17, pp. 435-444Ankarcrona, M., Dypbukt, J.M., Orrenius, S., (1996) FEBS Lett, 394, pp. 321-324Campos, C.B.L., Degasperi, G.R., Pacífico, D.S., (2004) Biochem Pharmacol, 68, pp. 2197-2206Collins, R., Armitage, J., Parish, S., (2003) Lancet, 361, pp. 2005-2016Dawson, T.M., Steiner, J.P., Dawson, V.L., (1993) Proc Natl Acad Sci U S a, 90, pp. 9808-9812Degasperi, G.R., Velho, J.A., Zecchin, K.G., (2006) J Bioenerg Biomembr, 38, pp. 1-10Demierre, M.-F., Higgins, P.D.R., Gruber, S.B., (2005) Nat Rev Cancer, 5, pp. 930-942Ghosh, P.M., Ghosh-Choudhury, N., Moyer, M.L., (1999) Oncogene, 18, pp. 4120-4130Gunter, K.K., Gunter, T.E., (1994) J Bioenerg Biomembr, 26, pp. 471-485Halestrap, A.P., Brenner, C., (2003) Curr Med Chem, 10, pp. 1507-1525Halestrap, A.P., Connern, C.P., Griffths, E.J., (1997) Mol Cell Biochem, 174, pp. 167-172Hara, M.R., Snyder, S.H., (2007) Toxicol, 47, pp. 117-141Hindler, K., Cleeland, C.S., Rivera, E., (2006) Oncologist, 11, pp. 306-315Holden, M.J., Sze, H., (1989) Plant Physiol, 91, pp. 1296-1302Hoque, A., Chen, H., Xu, X.C., (2008) Cancer Epidemiol Biomarkers Prev, 17, pp. 88-94Kowaltowski, A.J., Castilho, R.F., Vercesi, A.E., (2001) FEBS Lett, 495, pp. 12-15Kroemer, G., Galluzi, L., Brenner, C., (2007) Physiol Rev, 87, pp. 99-163Li, Y.C., Park, M.J., Ye, S.-K., (2006) Am J Pathol, 168, pp. 1107-1118Liu, J., Farmer, J.D.J., Lane, W.S., Friedman, J., (1991) Cell, 66, pp. 807-815Manev, H., Favaron, M., Candeo, P., (1993) Brain Res, 624, pp. 331-335Marcelli, M., Glenn, R.C., Haidacher, S.J., (1998) Cancer Res, 58, pp. 76-83Park, C., Lee, I., Kang, W.K., (2001) Carcinogenesis, 22, pp. 1727-1731Platz, E.A., Leitzmann, M.F., Visvanathan, K., (2006) J Natl Cancer Inst, 98, pp. 1819-1825Rao, S., Porter, D.C., Chen, X., (1999) Proc Natl Acad Sci U S a, 96, pp. 7797-7802Shepherd, J., Cobbe, S.M., Ford, I., (1995) N Engl J Med, 333, pp. 1301-1307Shibasaki, F., McKeon, F., (1995) Cell Biol, 131, pp. 735-743Sivaprasad, U., Abbas, T., Dutta, A., (2006) Mol Cancer Ther, 5, pp. 2310-2316Springer, J.E., Azbill, R.D., Nottingham, S.A., (2000) J Neurosci, 20, pp. 7246-7251Ukomadu, C., Dutta, A., (2003) J Biol Chem, 278, pp. 4840-4846Velho, J.A., Okanobo, H., Degasperi, G.R., (2006) Toxicology, 219, pp. 124-132Vercesi, A.E., Kowaltowski, A.J., Oliveira, H.C.F., (2006) Front Biosc, 11, pp. 2554-2564Wang, H.G., Pathan, N., Ethell, I.M., (1999) Science, 284, pp. 339-343Weitz-Schmidt, G., Welzenbach, K., Brinkmann, V., (2001) Nat Med, 7, pp. 687-692Zecchin, K.G., Seidinger, A.L.O., Degasperi, G.R., (2007) J Bioenerg Biomembr, 39, pp. 186-19

Doses e fontes de nitrogênio na recuperação de pastagens do capim-marandu Nitrogen doses and sources on pasture recuperation of grass marandu

Avaliaram-se o efeito de doses e fontes de nitrogênio na recuperação do capim-marandu, por um período de três anos, em pastagem estabelecida há mais de 10 anos, com baixa produção de forragem. O delineamento experimental foi em blocos completos ao acaso, com três repetições. Nas parcelas foi utilizado o fatorial 2 x 4, sendo duas fontes de nitrogênio (sulfato de amônio e uréia) e quatro doses de nitrogênio (0, 100, 200 e 300kg ha-1 ano-1). Nas subparcelas, foram alocados os três anos (2004, 2005 e 2006), referentes ao tempo de recuperação da pastagem. A aplicação de nitrogênio foi determinante para a recuperação do capim-marandu. A maior produção de massa seca foi observada no segundo ano e o maior teor de proteína bruta no terceiro ano de recuperação da pastagem. As maiores doses de nitrogênio promoveram acréscimos lineares na produção de massa seca e redução nos teores de fibra em detergente neutro e fibra em detergente ácido. O sulfato de amônio promoveu maior produção de massa seca do que a ureia, em todas as doses e anos avaliados.<br>The effects of nitrogen doses and sources were evaluated on pasture recuperation of grass marandu, in a three-year period. The pasture was established for more than ten years and it was presenting low herbage production being considered in moderate degradation phase. The experiment was arranged in a randomized complete block design with split-plots and three replications, in a 2x4 factorial, being two sources of N (ammonium sulphate and urea) and four doses of N (0, 100, 200, and 300kg ha-1 yr-1). The time of pasture evaluation was represented by the years 2004, 2005, and 2006. The highest dry matter production was observed in the second year and the highest crude protein in the third one. The highest nitrogen doses promoted linear increase on dry mass production and decrease in fiber concentration and in neutral and acid detergents. Ammonium sulphate resulted in higher dry mass production than urea in all doses applied and evaluated years

Rehabilitation with forage grasses of an area degraded by urban solid waste deposits

Dry matter yield and chemical composition of forage grasses harvested from an area degraded by urban solid waste deposits were evaluated. A split-plot scheme in a randomized block design with four replicates was used, with five grasses in the plots and three harvests in the subplots. The mineral content and extraction and heavy metal concentration were evaluated in the second cut, using a randomized block design with five grasses and four replicates. The grasses were Brachiaria decumbens cv. Basilisk, Brachiaria ruziziensis, Brachiaria brizantha cv. Marandu and cv. Xaraés, and Panicum maximum cv. Tanzânia, cut at 42 days of regrowth. The dry matter yield per cut reached 1,480 kg ha-1; the minimum crude protein content was 9.5% and the average neutral detergent fiber content was 62.3%. The dry matter yield of grasses was satisfactory, and may be an alternative for rehabilitating areas degraded by solid waste deposits. The concentration of heavy metals in the plants was below toxicity levels; the chemical composition was appropriate, except for phosphorus. The rehabilitated areas may therefore be used for grazing