Himatanthus sucuuba, SPRUCE (M. ARG.) WOODSON (Apocynaceae) ("Bellaco-Caspi"), a tree from the Amazon rain forest, has received much attention in the literature for the treatment of various ailments, although the ethnobotanical information is somewhat contradictory. For example, in Perú, an infusion from the stem bark has been used as wound-healing agent, for the treatment of tumors, boils and swellings, against arthritis, as a vermifuge laxative, 1) and as hallucinogen.2) In Brazil, on the other hand, the dried bark is alleged to have anti-ulcer and aphrodisiac activities whereas the latex is used as an antitumor agent.3) The Caboclos in the Amazon use the dried stem bark for its analgesic and anti-tussive activities. 4) In Colombia, the root is said to be very poisonous. 5)The toxicity of the reproductive system and teratogenic potential of the stem bark have been investigated. 6) Recently, two lichen depsides found in the bark of H. sucuuba, have shown inhibition against monoamine oxidase-B.7) The in vivo cicatrizant activity of H. sucuuba has been investigated by our group. Although, in an initial experiment, an extract of the bark of H. sucuuba showed significant cicatrizant activity, this result could not be reproduced in subsequent runs.8) An acute toxicity screening-after i.p. administration of 0.1 to 1 mg of extract per gram of mouse weight-determined that H. sucuuba was non-toxic in this range.As part of our systematic search for potential anti-cancer agents from plants, 9) an extract of the bark of H. sucuuba underwent a mechanism-based bioassay fractionation. Our assay uses engineered yeasts which lack the RAD52 DNA repair pathway, one of the three major DNA repair pathways that have been defined in yeast, and may also lack the gene for topoisomerase I.10) An extract which inhibits these yeast mutants to a greater extent than it inhibits the wild-type strain RS188N is thus expected to contain agents which induce DNA damage. Results and DiscussionThe ethanolic extract of the bark of H. sucuuba [IC 12 ϭ 4000 mg/ml (RS321)] was partitioned between hexane and 80% aq. methanol, resulting in enhanced activity in the latter fraction. Further partitioning (60% aq. methanol/CH 2 Cl 2 ) concentrated the activity in the dichloromethane fraction (IC 12 ϭ380 mg/ml). Chromatographic purification of this fraction led to the isolation of a known iridoid lactone, plumericin (1), 11) responsible for the DNA damaging activity of the extract. The activity observed was relatively weak, with an IC 12 value of 70 mg/ml for the RS321 yeast strain. For comparison purposes, the known active agent streptonigrin 12) has an IC 12 value of 0.65 mg/ml against RS321. Compound 1 is a known antifungal which has been isolated previously from H. sucuuba 7) and other Himatanthus species.13)The non-polar (hexane) fraction was investigated for its in vitro differential cytotoxic activity using various cancer cell lines (H460, ME180, DU145, MCF-7, HT29). The resulting 50% growth inhibition (GI 50 ) values were greater than the control (BA...

We estimate pass-through effects of international food price movements into domestic food prices for eighteen countries in the Middle East and North Africa, using threshold regressions. International price movements transmit to various degrees into domestic prices. Transmission is mostly asymmetric, pushing domestic price levels up, as increases in international food prices are typically passed through, but declines are rarely transmitted. This situation is indicative of policy and market distortions, notably the presence of food subsidies in the context of fiscal constraints. Hence, both international prices and their volatility matter for domestic inflation, yet domestic factors also play a role.

We estimate pass-through effects of international food price movements into domestic food prices for eighteen countries in the Middle East and North Africa, using threshold regressions. International price movements transmit to various degrees into domestic prices. Transmission is mostly asymmetric, pushing domestic price levels up, as increases in international food prices are typically passed through, but declines are rarely transmitted. This situation is indicative of policy and market distortions, notably the presence of food subsidies in the context of fiscal constraints. Hence, both international prices and their volatility matter for domestic inflation, yet domestic factors also play a role.

This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the legal status of any territory or the endorsement or acceptance of such boundaries. Nothing herein shall constitute or be considered to be a limitation upon or waiver of the privileges and immunities of The World Bank, all of which are specifically reserved..

Existing literature repeatedly documented a strong correlation between trade and growth. It has also shown a causal effect of imports (though not necessarily exports) on growth in simultaneous equation models but to a lesser extent in Granger-causality tests. Export and import taxes have sometimes been found to negatively affect growth. Drawing policy conclusions from these general findings for a particular country is difficult not only because of the contradictory results but also because of potential second best world effects and the implied endogeneity of trade policy. Policy recommendations for a specific country require a careful analysis of market and institutional arrangements and can not be based on the existing cross-country literature. Copyright Springer-Verlag Berlin Heidelberg 2004Theoretical and Empirical Trade and Growth Studies, Policy Recommendations, F13 Commercial Policy, Protection, Promotion, Trade Negotiations, O1 Economic Development,