Modelos de minimização de biomassa residual

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anatomia de ápices radiculares de feijão cv. carioca submetidos a níveis de boro em solução nutritiva

Foram estudadas as alterações anatômicas em ápices radiculares do feijoeiro (Phaseolus vulgaris L. cv. Carioca), quando submetidos a diferentes níveis de boro em solução nutritiva. Através de um experimento inteiramente casualizado, foram realizados três tratamentos como se segue: T1 0,50 mg L-1 de boro (testemunha); T2 0,25 mg L-1 de boro (nível intermediário); T0 omisso em boro; sendo feitas amostragens em três estágios sucessivos de desenvolvimento da planta, no decorrer de seu ciclo. As alterações foram avaliadas efetuando-se secções longitudinais de ápices radiculares, sendo analisados comparativamente por meio de estudo cito-histológico com o emprego de microscópio de luz. Considerando como testemunha as plantas submetidas ao nível de 0,50 mg L-1 de boro na solução nutritiva, pôde-se verificar que a omissão desse micronutriente, na solução nutritiva, provocou inibição da divisão e alongamento celular, hipertrofia de células, desorganização de elementos vasculares em raiz, impedindo que a planta completasse seu ciclo, morrendo ao redor do 55o. dia após o transplante. O nível de 0,25 mg L-1 de boro, na solução nutritiva, embora tenha provocado desorganização no ápice radicular, não impediu o desenvolvimento da planta.

Application of C-banding in two Arachis wild species, Arachis pintoi Krapov. and W.C. Gregory and A-villosulicarpa Hoehne to mitotic chromosome analyses

Two wild diploid (2n = 20 chromosomes) and self-pollinating Arachis species, Arachis Pintoi Krapov and W.C.Gregory and A. villosulicarpa Hoehne were submmited to C-band technique to karyotype analyses. Root tips were employed in the analyses. Morphometric data chose that chromosome lengths varied from 3.12 in A. villosulicarpa to 1.45 in A. Pintoi. Karyotype formula obtained was 10sm to A. Pintoi and 9sm + 1m to A. villosulicarpa. There was a predominance of pericentromeric C-band in all mitotic metaphasic chromosomes in both species. Besides C-band values, both species still did not differ in respect to chromosome absolute and relative lengths, centromeric index, symmetry index and total karyotype haploid length. C-band and morphometric data did not show strong or significant differences which could separate these two species of peanut which belong to evolutive different sections.

A new species of Hyphessobrycon (Characiformes : Characidae) from rio Portuguesa, rio Orinoco basin, Venezuela

A new species of Hyphessobrycon is described from tributaries of the rio Portuguesa, rio Orinoco Basin, Venezuela. The new species is diagnosed from congeners by the presence of two large hooks on each side of the anal fin in adult males ( processes of last unbranched and first branched anal-fin rays), distal third of caudal-fin black except for its distal tips ( which are hyaline), anal-fin rays v, 19-21, and dorsal-fin rays ii, 8. Comments on its generic status and putative relationships are provided.

Endogenous and exogenous polyamines in the organogenesis in Curcuma longa L.

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Localized matrix metalloproteinase (MMP)-2 and MMP-9 activity in the rat ventral prostate during the first week of postnatal development

The initial events in prostatic morphogenesis involve cell proliferation, epithelial canalization and outgrowth toward the stroma. We have hypothesized that stromal rearrangement takes place at the sites of epithelial growth and branching and that this rearrangement involves the action of gelatinases matrix metalloproteinase (MMP)-2 and MMP-9. Thus, the purpose of the present study was to characterize structural aspects of epithelial growth during the first week of postnatal development of the rat ventral prostate and to investigate the expression, localization and activity of MMP-2 and MMP-9 during this period by histological, ultrastructural and immunocytochemical analysis, in addition to gel zymography, in situ zymography and Western blotting. An increasing complexity of prostatic architeture was observed within the first postnatal week. Concurrently, the stroma became more organized and some cells differentiated into smooth muscle cells. Reticulin fibers appeared in a basket-like arrangement around both growing tips and epithelial sprouts, associated with a fainter staining for laminin. MMP-2 and MMP-9 activities were detected. MMP-2/MMP-9 expression decreased during the first week. Developing epithelial cords showed strong and difuse gelatinolytic activity. This activity coincided with the distribution of MMP-2 as determined by immunocytochemistry. on the other hand, MMP-9 was rather concentrated at the epithelial tips. These results suggest that gelatinolytic activity (with contribution of both MMP-2 and MMP-9) in the epithelium and at the epithelium-stroma interface are at least in part responsible for the tissue remodeling that allows epithelial growth and its projection into the surrounding stroma.

High fat-induced obesity associated with insulin-resistance increases FGF-2 content and causes stromal hyperplasia in rat ventral prostate

Obesity affects sex hormone secretion, which can negatively influence prostatic structure, homeostasis, and disease. This investigation aimed to evaluate the repercussions of obesity induced by a high-fat diet on the rat prostate, with or without treatment with the aromatase inhibitor, Letrozole. Adult Wistar rats were fed a high-fat diet (20% saturated fat, O) for 15 weeks to induce obesity or received a balanced diet (4% fat, C). Then, a group of C and O rats were daily treated with Letrozole (1 mg/kg b.w. per day) for 2 weeks (CL and OL, respectively). Subsequently, ventral prostate was processed for analysis by transmission electron microscopy, immunohistochemistry, and Western blotting. Obesity decreased 70% of the testosterone plasma level. The prostate showed epithelial atrophy and dilated acini in the intermediate portion and epithelial wrinkling in the distal tips. The relative frequency of smooth muscle alpha-actin in the O group increased by 67%. Ultrastructurally, epithelial cells in obese animals presented altered secretory organelles, lipid droplets, and thicker subjacent fibromuscular layer. Letrozole treatment caused a partial restoration of the prostatic changes caused by obesity. Obesity increased the prostatic content of fibroblast growth factor-2 (FGF-2) by 150%, and Letrozole treatment increased this protein even more in the control and obese groups. This investigation shows that obesity provokes structural and ultrastructural changes in the epithelium of rat prostate; these changes might affect gland homeostasis and physiology. The epithelial and smooth muscle cell hyperplasia and increased FGF-2 expression observed in this experimental model of obesity/insulin-resistance might explain the high frequency of benign prostatic hyperplasia in insulin-resistant men.

A new species of Pseudopaludicola Miranda-Ribeiro, 1926 (Anura: Leiuperidae) from the state of Mato Grosso, Brazil, with comments on the geographic distribution of Pseudopaludicola canga Giaretta & Kokubum, 2003.

A new species of Pseudopaludicola is described from the state of Mato Grosso, western Brazil. The new species inhabits the transition zone between Brazilian Cerrado and Amazon rainforest in northern Mato Grosso, and is characterized by its medium size (snout-vent length 12-17 mm), lack of T-shaped terminal phalanges, toe tips not expanded laterally, presence of two antebrachial tubercles, and smooth upper eyelids. The advertisement call of the new species consists of a series composed of 11-74 non-pulsed notes. Mean dominant frequency is 3938 Hz. Each note presents a slight ascendant frequency modulation in its first half, and another ascendant modulation in its last half. We also present new data on the distribution and conservation status of Pseudopaludicola canga.

Crystallographic and spectroscopic characterization of a molecular hinge: Conformational changes in bothropstoxin I, a dimeric Lys49 phospholipase A2 homologue

Bothropstoxin I(BthTX-I) from the venom of Bothrops jararacussu is a myotoxic phospholipase A2 (PLA2) homologue which, although catalytically inactive due to an Asp49-->Lys substitution, disrupts the integrity of lipid membranes by a Ca2+-independent mechanism, the crystal structures of two dimeric farms of BthLTX-I which diffract X-rays eo resolutions of 3.1 and 2.1 Angstrom have been determined, the monomers in both structures are related by an almost perfect twofold axis of rotation and the dimer interfaces are defined by contacts between the N-terminal alpha-helical regions and the tips of the beta-wings of partner monomers. Significant differences in the relative orientation of the monomers in the two crystal forms results in open and closed dimer conformations, Spectroscopic Investigations of BthTX-I in solution have correlated these conformational differences with changes in the intrinsic fluorescence emission of the single tryptophan residues located at the dimer interface, the possible relevance of this structural transition in the Ca2+-independent membrane damaging activity is discussed. (C) 1998 Wiley-Liss, Inc.

Hyphessobrycon rutiliflavidus n. sp., a new characid fish from the upper rio Paraguai, State of Mato Grosso, Brazil (Characiformes : Characidae)

Hyphessobrycon rutiliflavidus, new species, is described from the upper rio Paraguai in Cuiaba, State of Mato Grosso, Brazil. The new species differs from all other congeners by the following combination of characters: black humeral spot, slightly diffuse at its tips, and caudal-peduncle blotch present; midlateral body stripe conspicuous in its posteriormost portion, extending to the tips of the middle caudal rays; anal fin with iii, 15 to iv, 19 rays (mode iv, 17); upper jaw length, 42.3 to 49.5% of the head length; maxilla with 2-5 teeth (mode 3); all the fins of males reddish-orange and of females yellowish.

Incidence of tarsonemid mites on Cocos nucifera L. (Arecaceae) from Oman with description of a new species of Nasutitarsonemus Beer and Nucifora (Acari: Tarsonemidae)

Coconut is an important crop grown in the coastal plain of the Dhofar region, south-eastern Oman, on the edge of the Arabian Peninsula desert. It holds a particular place in the landscaping of the region and is also of great interest for the production of coconut drinking water. One of the main pests of coconut in this region is the coconut mite (Aceria guerreronis Keifer). In surveys conducted to understand the dynamics of that mite and its association with other arthropods, the incidence of tarsonemid mites was determined. Steneotarsonemus furcatus de Leon was the most commonly found tarsonemid on fruits as well as on growing tips of coconut seedlings, always at low levels. A few representatives of an undescribed tarsonemid species were also found. That new species is here described as Nasutitarsonemus omani Lofego and Moraes, sp. nov. A key to the species of this little-known genus is provided.

A new species of Moenkhausia from the rio Amazonas and rio Orinoco basins (Characiformes: Characidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Confocal Laser Microscopic Analysis of Biofilm on Newer Feldspar Ceramic

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ultrasonic versus high-speed cavity preparation: Analysis of increases in pulpal temperature and time to complete preparation

Statement of problem. The use of ultrasonic tips has become an alternative for cavity preparation. However, there are concerns about this type of device, particularly with respect to intrapulpal temperatures and cavity preparation time.Purpose. The purpose of this study was to analyze pulpal temperature increases generated by an ultrasonic cavity preparation with chemical vapor deposition (CVD) tips, in comparison to preparation with a high-speed handpiece with a diamond rotary cutting instrument. The time required to complete the cavity preparation with each system was also evaluated.Material and methods. Thermocouples were positioned in the pulp chamber of 20 extracted human third molars. Slot-type cavities (3 x 3 x 2 mm) were prepared on the buccal and the lingual surfaces of each tooth. The test groups were: high-speed cavity preparation with diamond rotary cutting instruments (n = 20) and ultrasonic cavity preparation with CVD points (n = 20). During cavity preparation, the increases In pulpal temperature, and the time required for the preparation, were recorded and analyzed by Student's t test for paired samples (alpha = .05).Results. The average pulpal temperature increases were 4.3 degrees C for the high-speed preparation and 3.8 degrees C for the ultrasonic preparation, which were statistically similar (P = .052). However, significant differences were found (P < .001) for the time expended (3.3 minutes for the high-speed bur and 13.77 minutes for the ultrasound device).Conclusions. The intrapulpal temperatures produced during cavity preparation by ultrasonic tips versus high-speed bur preparation were similar. However, the use of the ultrasonic device required 4 times longer for the completion of a cavity preparation.

In vitro evaluation of apical sealing in root apex treated with demineralization agents and retrofiled with mineral trioxide aggregate through marginal dye leakage

O objetivo deste estudo foi avaliar o selamento de ápices radiculares tratados com diferentes agentes desmineralizantes e retrobturados com agregado de trióxido mineral (MTA), mediante infiltração marginal por corante. Cinqüenta e seis dentes unirradiculares humanos extraídos foram instrumentados, obturados e seccionados apicalmente. Os preparos cavitários apicais foram confeccionados com pontas ultra-sônicas e os agentes desmineralizantes foram aplicados previamente à retrobturação com Pro Root MTA. Os espécimes foram divididos aleatoriamente em 4 grupos (n=14): grupo 1 (sem agente desmineralizante); grupo 2 (ácido fosfórico 35% durante 15 s); grupo 3 (solução de EDTA 17%, pH 7, durante 3 min); grupo 4 (gel de EDTA 24%, pH 7, durante 4 min). A extensão da infiltração de corante (rodamina B 2% a 37°C, por 24 h) foi avaliada em milímetros utilizando-se um estereomicroscópio. Os resultados foram analisados estatisticamente por meio de análise de variância a um critério e do teste Tukey com nível de significância de 5%. Dentre os grupos experimentais, a menor extensão de infiltração do corante foi verificada no grupo 1 (1,89 mm), seguido pelos grupos 2 (2,18 mm), 4 (2,54 mm) e 3 (2,64 mm). Não houve diferenças estatisticamente significante (p>0.05) na infiltração marginal pelo corante entre os grupos 1, 2 e 4 e os grupos 2, 3 e 4. Com base nos resultados obtidos, pode-se concluir que a aplicação de agentes desmineralizantes não pode ser recomendada quando da utilização do MTA em cirurgias parendodônticas.