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Knowing the regeneration and structure of a species in different phytophysiognomies is extremely important to understand its pattern of occurrence. In spite of its importance, this type of study is still scarce in the Cerrado biome. In this perspective, this work aimed to compare the structure of the arboreal and regenerating strata of Annona coriacea in the cerrado sensu stricto and in the cerradão (savanna woodland). For that purpose, 13 plots of 400m² were installed in each physiognomy. All individuals of A. coriacea were sampled and had their diameter and height measured. The individuals were divided into regenerating and arboreal and were distributed in classes of height and diameter. Furthermore, the absolute density and the basal area of each extract were calculated in each physiognomy. The parameters were compared using the T-test. In total, 130 individuals of A. Coriacea were sampled, with 42 regenerating individuals in the cerrado sensu stricto and 49 in the cerradão. As for the arboreal individuals, 33 were sampled in the cerrado sensu stricto and 6 in the cerradão. All evaluated parameters revealed to be significantly different for the physiognomies. Based on these results, it is possible to affirm that A. coriacea did not present a distribution pattern in the two physiognomies, although it presents a better establishment success in the cerrado sensu stricto. In the cerradão, although the seeds can germinate, the seedlings fail to develop and reach the adult age. [ABSTRACT FROM AUTHOR]

The word angiogenesis indicates the formation of new vascular segments from existing vessels such as capillaries and venules. Blood vessel formation in tumors is the result of rapid, disorganized vascular growth through two distinct mechanisms: sprouting and intussusceptive angiogenesis. The objective of this study was to elucidate the morphological aspects of these two vascular growth mechanisms in oral squamous cell carcinoma induced in hamster buccal pouch. Eight Syrian golden hamsters had their right buccal pouch treated with DMBA 0.5% and 10% carbamide peroxide for 90 days in order to produce squamous cell carcinoma in this site. Next, buccal pouches of the animals were submitted to the vascular corrosion technique and then analyzed by scanning electron microscopy. The vascular figures of sprouts were observed in the entire vascular network of the buccal pouches, as opposed to the intussusceptive angiogenesis that was predominantly observed in the sub-epithelial network. It was possible to differentiate the figures of sprouts from artifacts by the analysis of the blind ending of these structures. Intussusceptive angiogenesis was identified by the presence of holes trespassing the lumen of the capillaries. Vascular expansion occurred through intussusceptive angiogenesis in two ways: by the fusion of the pillars to form a new capillary and, by increasing the girth of the pillar to form meshes. The method of corrosion associated with scanning electron microscopy proved to be an excellent tool to study the two types of angiogenesis in oral squamous cell carcinoma in the hamster buccal pouch. SCANNING 36:293-300, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]