Assessing biomass based on canopy height profiles using airborne laser scanning data in eucalypt plantations

This study aimed to map the stem biomass of an even-aged eucalyptus plantation in southeastern Brazil based on canopy height profile (CHPs) statistics using wall-to-wall discrete return airborne laser scanning (ALS), and compare the results with alternative maps generated by ordinary kriging interpolation from field-derived measurements. The assessment of stem biomass with ALS data was carried out using regression analysis methods. Initially, CHPs were determined to express the distribution of laser point heights in the ALS cloud for each sample plot. The probability density function (pdf) used was the Weibull distribution, with two parameters that in a secondary task, were used as explanatory variables to model stem biomass. ALS metrics such as height percentiles, dispersion of heights, and proportion of points were also investigated. A simple linear regression model of stem biomass as a function of the Weibull scale parameter showed high correlation (adj.R2 = 0.89). The alternative model considering the 30th percentile and the Weibull shape parameter slightly improved the quality of the estimation (adj.R2 = 0.93). Stem biomass maps based on the Weibull scale parameter doubled the accuracy of the ordinary kriging approach (relative root mean square error = 6 % and 13 %, respectively)

Antiulcerogenic Activity Of Ethanol Extract Of Solanum Variabile (false "jurubeba")

The ethanol extract (EE) of the aerial parts of Solanum variabile Mart. (Solanaceae) was investigated for its ability to prevent ulceration of the gastric and duodenal mucosa at different doses. Its ability to heal chronic ulcer processes was also evaluated. When the HCl/ethanol solution was used to induce gastric ulcer, the EE produced a significant dose-dependent reduction of lesion formation of 51, 74 and 89%, at doses of 250, 500 and 1000 mg/kg, respectively. The 100 mg/kg dose had no significant activity. The EE also significantly reduced the gastric lesions induced by the combination of indomethacin and bethanechol (60 and 72%) at doses of 500 and 1000 mg/kg and also reduced stress-induced gastric ulcer (41%) but only at the doses of 1000 mg/g (P<0.05). The pylorus-ligature experiment demonstrated that the highest EE dose affected significantly the gastric juice parameters by increasing pH values from 4.08 (negative control) to 5.42 and decreasing acid output from 7.16 (negative control) to 4.26 mEq. mL, 4 h. A decrease of gastric contents from 370 mg (negative control) to 240 mg was also observed. The results obtained in the chronic gastric ulcer model indicated that a single oral dose of Solanum variabile (1000 mg/kg) administered for 14 consecutive days accelerated the ulcer healing by 46% compared to a 55% effect of cimetidine. Also, at the dose of 1000 mg/kg, the EE inhibited the onset of duodenal lesions by 64%. The data suggest that the EE of Solanum variabile has a significant preventive, curative and duodenal anti-ulcer effect. © 2004 Elsevier Ireland Ltd. All rights reserved.9318388(1972) Flora Paulista, p. 74. , Boletin no. 13, São PauloCôrrea Pio, M., (1984) Dicionário de Plantas Úteis Do Brasil e Das Exóticas Cultivadas, 4, p. 573. , Ministério da AgriculturaHalter, F., Schmassmann, A., Tarnawski, A., Healing of experimental gastric ulcers - Interference by gastric acid (1995) Digestive Disease Sciences, 40, pp. 2481-2486Hunt, H.R., Cederberg, C., Dent, J., Halter, F., Howden, C., Marks, S.I.N., Rune, S., Walt, R.P., Optimizing acid suppression for treatment of acid-related diseases (1995) Digestive Disease Sciences, 40, pp. 24s-49sIto, M., Segami, T., Inagguma, K., Suzuki, Y., Cimetidine and omeprazole accelerate gastric ulcer healing by an increase in gastrin secretion (1994) European Journal of Pharmacology, 263, pp. 251-259Leitão Filho, H.F., (1972) Plantas Invasoras de Cultura, 549p. , Ministério da Agricultura, HUCITEC, São PauloLevine, R.J., A method for rapid production of stress ulcers in rats (1971) Peptic Ulcer, pp. 92-97. , Pfeiffer, C.J. (Ed.). Munksgaard, Copenhagen, 1971Lewis, D.A., Hanson, P.J., Anti-ulcer drugs of plant origin (1991) Progress in Medicinal Chemistry, pp. 201-231. , Ellis, G.P., West, G.B. (Eds.). Elsevier Science Publishers Co., AmsterdamMizui, T., Douteuchi, M., Effect of polyamines on acidified ethanol-induced gastric lesions (1993) Japanese Journal of Pharmacology, 33, pp. 939-945Poulsen, S.S., Olsen, S.P., Kirkegaard, P., Healing of cysteamine-induced duodenal ulcer in the rat (1985) Digestive Disease Sciences, 30, pp. 161-167Rainsford, K.D., Gastric ulcerogenicity of non-steroidal anti-inflammatory drugs in mice with mucosa sensitized by cholinomimetic treatment (1978) Journal of Pharmaceutics and Pharmacology, 39, pp. 669-672Sacco, J.C., (1985) Ervas Daninhas Do Brasil Solanaceae I Gênero Solanum L., p. 104. , CNPDA, EMBRAPA, Boletim Técnico, BrasiliaShay, H., Komarov, S.A., Fels, S.S., Meranze, D., Gruenstein, M., Siplet, H., A simple method for the uniform production of gastric ulceration in the rat (1945) Gastroenterology, 5, pp. 43-61Skarstein, A., Svanes, K., Varhaug, J.E., Soreide, O., Blood flow distribution in the stomach of cats with acute gastric ulcer (1979) Scandanavian Journal of Gastroenterology, 14, pp. 897-903Smith, L.B., Downs, R.J., Solanaceas (1966) Flora Ilustrada Catarinense, pp. 1-321. , Reitz, R. (Ed.). Itajaí, Herbário Barbosa RodriguesSouza Brito, A.R.M., Dose Simples (1994) Manual de Ensaios Toxicológicos in Vivo, pp. 15-22. , Editora UNICAMP, CampinasSzabo, S., Animal models of human disease: Cysteamine induced acute and chronic duodenal ulcers in the rat (1978) American Journal of Pathology, 93, pp. 273-276Szabo, S., Mechanisms of mucosal injury in the stomach and duodenum: Time-sequence analysis of morphologic, functional, biochemical and histochemical studies (1987) Scandinavian Journal of Gastroenterology, 22, pp. 21-28Szabo, S., Vincze, A., Growth factors in ulcer healing: Lessons from recent studies (2000) Journal of Physiology (Paris), 94, pp. 77-81Takagi, K., Okabe, S., Saziki, R., A new method for the production of chronic gastric ulcer in rats and the effect of several drugs on its healing (1969) Journal of Pharmacy, 19, pp. 418-426Wolfe, M.M., Sachs, G., Acid suppression: Optimizing therapy for gastroduodenal ulcer healing, gastroesophageal reflux disease, and stress-related erosive syndrome (2000) Gastroenterology, 118, pp. 9-s31Yesilada, E., Gurbuz, I., Ergun, E., Effects of Cistus laurifolius L. flowers on gastric and duodenal lesion (1997) Journal of Ethnopharmacology, 55, pp. 201-22

Gastroprotective effect of essential oil from Croton cajucara Benth. (Euphorbiaceae)

Rodriguez, J. Instituto de Biologia, Universidad de Talca, Talca, ChileThe gastroprotective activity of the essential oil from the bark of Croton cajucara Benth (Euphorbiaceae) was assessed in three different models of experimentally induced gastric ulcer in mice. At oral dose of 100 mg/kg the essential oil reduced gastric lesions induced by hypothermic restraint stress and HCl/ethanol significantly. In the HCl/ethanol model a dose-dependent gastroprotective effect was found. Moreover, significant changes in gastric parameters such as pH, secretion rate and total gastric acid were found after intraduodenal administration of essential oil under ligated pylorus (Shay) conditions. The acute toxicity of essential oil was assessed in mice. The LD50 values were 9.3 and 680 mg/kg for oral and intraperitoneal administrations, respectively. The cytotoxicity of essential oil was studied also. A dose-dependent cell viability inhibition was found in V79 fibroblast cell cultures with an IC50 of 22.9 μg/ml. Our results support the pharmacological study of this essential oil