The vacuum assisted closure of complex wounds: report of 3 cases

Treatment of wounds using conventional methods is frequently limited by inadequate local wound conditions, or by a poor systemic clinical situation. Vacuum system may promote faster granulation tissue formation, remove excessive exudate, increase blood flow in the wound, and attract the borders of the wound to the center, reducing its dimension. We present 3 cases of patients with difficult wounds, due to bad local conditions, or poor clinical situation, in whom we used a vacuum system to prepare the wound for the surgical closure. One patient had a pressure ulcer, another had a diabetic foot ulcer, and the third one had an open foot stump. In the 3 cases a significant improvement of the wound conditions was achieved after 7 to 8 days, allowing successful surgical treatment with flap or skin grafts.

The Simaba guianensis complex in northers South America

With additional data from specimens not studied by previous workers, the confusing Simaba guianensis compex was re-analized. Simaba polyphylla is recognized as a distinct species and two subspecies of S. guianensis are maintained. Simaba polyphylla, S. guianensis ssp. guianensis, and S. guianensis ssp. ecaudata are keyed, described, and illustrated and specimens examined are cited for each. Specimens of S. guianensis ssp. ecaudata show great morphological diversity but can be separeted into three groups. Further collecting may provide information that shows these groups to be worthy of separate taxonomic status.

Taxonomy of the Oenocarpus-Jessenia (Palmae) complex in Brazil

Two genera, Oenocarpus and Jessenia are recognized in this complex of Neotropical palms. They are well represented in Brasil, Oenocarpus with seven species (O. distinchus, O. discolar, O. tarampabo, O. bacaba, O. macrocalyx, O. mapora and O. minor, and Jessenia with one species, J. bataua). Many of these taza are poorly know and under-represented in herbaria, both in Brazil and elsewhere. A great deal of fieldwork is needed to betther undestand the basic biology and extent of variation in the populations of these palms.

Soil mineral N dynamics beneath mixtures of leaves from legume and fruit trees in Central Amazonian multi-strata agroforests

Long term applications of leguminous green mulch could increase mineralizable nitrogen (N) beneath cupuaçu trees produced on the infertile acidic Ultisols and Oxisols of the Amazon Basin. However, low quality standing cupuaçu litter could interfere with green mulch N release and soil N mineralization. This study compared mineral N, total N, and microbial biomass N beneath cupuaçu trees grown in two different agroforestry systems, north of Manaus, Brazil, following seven years of different green mulch application rates. To test for net interactions between green mulch and cupuaçu litter, dried gliricidia and inga leaves were mixed with senescent cupuaçu leaves, surface applied to an Oxisol soil, and incubated in a greenhouse for 162 days. Leaf decomposition, N release and soil N mineralization were periodically measured in the mixed species litter treatments and compared to single species applications. The effect of legume biomass and cupuaçu litter on soil mineral N was additive implying that recommendations for green mulch applications to cupuaçu trees can be based on N dynamics of individual green mulch species. Results demonstrated that residue quality, not quantity, was the dominant factor affecting the rate of N release from leaves and soil N mineralization in a controlled environment. In the field, complex N cycling and other factors, including soil fauna, roots, and microclimatic effects, had a stronger influence on available soil N than residue quality.