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Paubrasilia echinata (brazilwood) is an endangered native tree from the Brazilian Atlantic Forest whose seeds tolerate maturation drying, but, unlike classic orthodox seeds, they quickly lose viability after shedding. This work analyzed the biochemical and ultrastructural changes during the maturation of brazilwood seeds, with particular attention to the cell walls and organization of the cellular components. The physiological seed maturity was accompanied by increased starch content and decreased soluble sugars. Arabinose increased considerably and was the predominant cell-wall sugar during maturation, suggesting a rise in arabinans that contribute to greater cell wall flexibility. This increase was consistent with the cell wall infolding observed in the hypocotyl axis and cotyledons during the maturation of brazilwood seeds. Ultrastructural analyses showed changes in the number and distribution of protein bodies and amyloplasts and the reorganization of lipid droplets into large drops or masses during seed desiccation. Our findings demonstrate that brazilwood seeds behave like other orthodox seeds during maturation, performing the cell wall and metabolic changes before the major decline in the seed water content. However, the high vacuolization and reorganization of lipid bodies observed at 65 DAA suggest that cell deterioration occurs to some extent at the end of the maturation period and could be responsible for reducing the longevity of the brazilwood dried seeds.

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O aspecto natural e a estética da interface dos tecidos moles e restaurações peri-implantares requerem uma faixa adequada de tecido queratinizado. A ausência desta representa um obstáculo à higiene bucal. O objetivo deste artigo foi descrever uma nova abordagem para o segundo estágio cirúrgico para implantes adjacentes na região posterior da maxila, visando aumentar a quantidade e a qualidade do tecido queratinizado em áreas onde este se encontra reduzido ou inexistente. A técnica de reposição apical com retalho palatino (Rarp) foi realizada e descrita em detalhes, através de um relato de caso clínico.

The natural aspect and esthetics of the peri-implant tissues and restorations requires a suitable range of keratinized tissue. Their absence also represents an obstacle to the oral hygiene. The pur pose of this article is to describe a new approach at the second surgical stage for adjacent implants in the posterior region of the maxilla aiming to increase the quantity and quality of the keratinized tissue in areas where it is reduced or nonexistent. The apical repositioning with palatal rotation (RARP) technique was performed and described in detail using a clinical case report.

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OBJECTIVE: Bisphosphonates (BPs) have been widely used in the treatment of bone disorders due to their ability to modulate bone turnover. The biological mechanisms through BFs exert their effects on osteoclasts are well established. However, the role of BFs on the osteoblasts is controversial. The present study aimed to evaluate the effects of risedronate on osteoblastic cells. DESIGN: MC3TE-E1 cells were exposed to risedronate at 0, 10(-8), 10(-6), 10(-4), and 10(-3)M. The following parameters were assayed: (1) cell proliferation by hemocytometer counting after 24, 48 and 72h, (2) cell viability by MTT assay after 24, 48 and 72h, (3) Type I Collagen quantification by ELISA after 24, 48 and 72h, (3) alkaline phosphatase activity after 7 and 10days and (4) matrix mineralization after 14days. RESULTS: After 24h, risedronate did not affect both cell proliferation and viability (p>0.05). However, after 48 and 72h, a decrease in cell proliferation and viability was detected in osteoblastic cultures exposed to risedronate at 10(-4) and 10(-3)M (p<0.05). After 48 and 72h, Type I Collagen synthesis was stimulated by risedronate at 10(-4)M (p<0.05). High levels of ALP activity were detected in cultures exposed to risedronate at 10(-4)M after 7 and 10days (p<0.05). After 14day, high calcium content was observed in cultures exposed to risedronate at 10(-4)M (p>0.05). CONCLUSION: These results indicated that risedronate can promote osteoblast differentiation.

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The arils of Bixa orellana L. seeds contain carotenoid storage cells (CSCs). The main compounds in these cells include bixin and norbixin, which are important pigments in the food and pharmaceutical industries. Although many studies have been conducted on these chemical constituents, the cellular events that occur during the development of the carotenoid-accumulating cells in the arils and their relationship with the final carotenoid accumulation in the vacuoles remain unknown. In this study, the development of the CSCs in B. orellana arils was analyzed by light and transmission electron microscopy. Carotenoids formed in specialized cells, whose number and size increased during aril development. At various stages of development, the cytoplasm of the CSCs contained chromoplasts that held an extensive network of tubules and plastoglobules. Next to the chromoplasts, lipid droplets may fuse one another to form osmiophilic bodies. In addition, vesicles were observed next to the tonoplast. At the final stages of development, both the osmiophilic bodies and vesicles, which became quadrangular or rectangular, were stored in the vacuoles of the CSCs. This study reported for the first time the occurrence of different storage unit types within the vacuole of carotenoid storage cells.

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A osteonecrose dos maxilares é uma das principais complicações relacionadas ao uso de medicamentos antirreabsortivos. Este artigo teve como objetivo relatar dois casos clínicos nos quais as pacientes desenvolveram osteonecrose dos maxilares induzida por bisfosfonatos, após instalação de implantes dentários. Em ambos os casos, as pacientes não relataram uso de bisfosfonatos. No primeiro caso, a região afetada foi a maxila, tendo sido utilizado o tratamento para infecção durante muitos meses até que, após remoção de sequestro ósseo, obteve-se o diagnóstico da patologia. O tratamento conservador com laser de baixa potência e antibioticoterapia obteve sucesso. No segundo caso, a paciente apresentou sequestro ósseo na região dos implantes dentários após realizar clareamento de um dente vizinho à região. O tratamento conservador não foi bem-sucedido, e a cirurgia para ressecção em bloco foi necessária. Nas duas situações, as pacientes só revelaram ter feito uso de medicação antirreabsortiva após serem questionadas diretamente, quando apresentaram sequestro ósseo. Uma anamnese dirigida e medidas para prevenção da complicação devem ser tomadas em pacientes que fazem ou fi zeram uso deste tipo de droga.

The osteonecrosis of the jaws is the main complication related to the use of anti-resorptive drugs. This article aims to report two clinical cases where the patients developed bisphosphonate-associated osteonecrosis of the jaw following dental implant installation. In both cases, both patients did not report use of bisphosphonates. In the first case, the affected region was the maxilla and it was treated as an infection for several months, until removal of bone sequestration, with the pathology diagnosed. The conservative treatment with low intensity laser and antibiotic therapy achieved success. In the second case, the patient presented bone sequestration around dental implants after performing internal tooth whitening in the neighboring region. The conservative treatment was not successful and surgery for bone resection was necessary. In both cases, the patients revealed to have used anti-resorptive drugs only after being directly questioned when bone sequestration was observed. A directed medical history and preventive measures should be taken with patients that use or have used this medication.

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The aim of this work was to investigate the starch degradation of bananas stored at low temperature (13°C, cold-stored group) and bananas stored at 19°C (control group) during ripening. The starch granules were isolated during different stages of banana ripening, and their structure was investigated using different techniques. The activities of α-amylase and ß-amylase associated to the starch granules were determined, and their presence was confirmed using immunolocalization assays. The increased molecular mobility likely facilitated the intake and action of α-amylase on the granule surface, where it was the prevalent enzyme in bananas stored at low temperature. The 10 days of storage at low temperature also influenced the sizes and shapes of the granules, with a predominance of rounded granules and pits on the surface along with superior amylose content, the higher amounts of amylopectin A-chains and the subtle increase in the A-type allomorph content.

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During mango ripening, soluble sugars that account for mango sweetening are accumulated through carbon supplied by both photosynthesis and starch degradation. The cultivar Keitt has a characteristic dependence on sugar accumulation during starch degradation, which takes place during ripening, only a few days after detachment from the tree. Most knowledge about starch degradation is based on seeds and leaves currently used as models. However, information about the mango fruit is scarce. This work presents the evaluation of alpha- and beta-amylases in the starch granule surface during fruit development and ripening. Extractable proteins were assayed for amylase activity and detected by immunofluorescence microscopy and correlated to gene expression. The results suggest that both amylases are involved in starch degradation during mango ripening, probably under the dependence of another signal triggered by the detachment from the mother-plant.

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The starch content of unripe mango Keitt is around 7% (FW), and it is converted to soluble sugars during the ripening of the detached fruit. Despite the importance of starch-to-soluble sugar metabolism for mango quality, little literature is found on this subject and none concerning the physical aspects of starch degradation. This manuscript presents some changes in the physical aspects of the starch granule during ripening, as analyzed by light microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). According to the analysis, unripe Keitt-mango-starch being spherical in shape and measuring around 15 microm, has A-type X-ray diffraction pattern with a degree of crystallinity around 21% with slight changes after 8 days of ripening. AFM images of the surface of the granules showed ultra microstructures, which are in agreement with a blocklet-based organization of the granules. The AFM-contrast image of growing layers covering the granule showed fibril-like structures, having 20 nm in diameter, transversally connecting the layer to the granule. The appearance of the partially degraded granules and the pattern of degradation were similar to those observed as a result of amylase activity, suggesting a hydrolytic pathway for the degradation of starch from mango cultivar Keitt. These results provide clues to a better understanding of starch degradation in fruits.

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A new powdery mildew infecting papaya (Carica papaya) in Brazil, Streptopodium caricae sp. nov., is described. The species is compared with other anamorphic Erysiphales known to infect papaya: Oidiopsis sicula, Ovulariopsis papayae, Oidium caricae, O. papayae, O. caricicola, O. indicum, O. caricae-papayae, Podosphaera (syn. Sphaerotheca) spp., and Erysiphe spp. An emended description Streptopodium and a key to the anamorphs of powdery mildews on papaya are also presented. A re-examination of the type material of Phyllactinia caricaefolia showed that conidia in this material are dimorphic, indicating that its anamorph does not belong to Ovulariopsis and that the teleomorph is not conspecific with Phyllactinia guttata. Oidium caricae, the common powdery mildew of papaya, was re-examined, recognized as a member of subgenus Pseudoidium, an emended description was prepared, and a new type was indicated. O. papayae was recognized as a synonym of O. caricae, and many of the records of this fungus are considered to be doubtful or incorrect, either omitting a description of the fungus or including a description or illustration of an euodium conidiophore morphology.

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The yellow passion fruit, Passiflora edulis f. flavicarpa, is one of the most important Brazilian fruit crops. It is an allogamous, diploid, and self-incompatible species. It has hermaphrodite, solitary flowers, located in the leaf axils and protected by leaf bracts. The flower has an androgynophore, which is a straight stalk supporting its reproductive parts. There are usually five anthers, located at the tip of each of the five filaments. The ovary is borne just above the filaments, at the top of the androgynophore; there are three styles that are united at their base, and at the top there are three stigmas. The objective of this research was to observe embryo sac development in yellow passion flowers. Ovaries at different stages of development were fixed in FAA (formalin, acetic acid and alcohol solution), hydrated, stained with Mayer's hemalum, and dehydrated. Ovules were cleared by using methyl salicylate, mounted on slides, and observed through a confocal scanning laser microscope. The yellow passion fruit ovule is bitegmic, crassinucellate, and anatropous, and its gametophyte development is of the Polygonum type. After meiosis, functional megaspores under go three successive mitotic divisions, resulting in an eight-nucleate megagametophyte: the egg apparatus at the micropylar end, two polar nuclei at the cell center, and three antipodals at the chalazal end. The egg apparatus is formed by an egg cell and two synergids, each with a filiform apparatus. The mature embryo sac has an egg cell, two synergids, two polar nuclei, and three antipodes, as has been described for most angiosperms

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