62 resultados para leaf and root anatomy
Resumo:
Aspects related to the nature of stem thickening in monocotyledons have been the subject of many studies. Primary thickening has been attributed to the Primary Thickening Meristem (PTM). According to most authors, it gives rise, besides the adventitious roots, to the vascular tissues and part of the cortex. In other words, it has centripetal and centrifugal activity. For some authors, however, it gives rise only to the vascular system, and for others, only to part of the cortex. However, this work demonstrated that PTM corresponds to the pericycle in the meristematic phase or to the pericycle associated with the endodermis, also with meristematic activity. It was observed that the pericycle was responsible for the formation of the vascular system of the rhizome and of the adventitious roots; the endodermis gave rise to cell layers with radial disposition which comprised the inner portion of the stem cortex, and which corresponded to the region known as the derivatives of the meristematic endodermis (DME). A continuity was also demonstrated between the tissues of the stem and root in species of Scleria Berg. (Cyperaceae).
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Os mecanismos biológicos desenvolvidos para aumentar a qualidade da regeneração óssea e da reparação tecidual de sítios periodontais específicos continuam a ser um desafio e têm sido complementado pela capacidade de adesão celular do colágeno do tipo I, promovida por um peptídeo sintético de adesão celular (P-15), associado a uma matriz inorgânica de osso (MIO) para formar MIO/P-15. O objetivo deste estudo foi avaliar a perda do nível clínico de inserção e a resposta da bolsa periodontal em dentes após 3 e 6 meses da aplicação de enxerto com MIO/P-15. Vinte e um cães do Hospital Veterinário da Universidade de São Paulo foram anestesiados para realização de tratamento periodontal e 132 faces dentais com perda de nível clínico de inserção foram tratadas, sendo que 36,4% (48 faces) receberam o peptídeo de adesão celular e 63,6% (84 faces) compuseram o grupo controle que recebeu tratamento convencional (retalho muco-gengival e aplainamento radicular). O procedimento foi documentado através de radiografia intra-oral e todas as sondagens de bolsas periodontais foram fotografadas. Depois de 3 e de 6 meses, os animais foram re-anestesiados a fim de se obter novas avaliações, radiografias, fotografias e sondagens periodontais. As 48 faces com perda de nível clínico de inserção que receberam material de enxertia apresentaram taxa de 40% de recuperação do nível clínico de inserção após 6 meses. O grupo controle de faces dentais não apresentou alteração do nível clínico de inserção. A face palatina foi a que apresentou melhor taxa de regeneração (40%) e os dentes caninos e molares mostraram as melhores respostas (57,14% e 65%, respectivamente). Não houve sinais de infecção pós-cirúrgica relacionadas à falta de higienização oral dos animais. Pode-se concluir que o MIO/P-15 auxilia na regeneração e re-aderência das estruturas periodontais, incluindo osso alveolar. Sua aplicação mostrou-se fácil e prática e a incidência de complicações pós-cirúrgicas foi baixa. Ainda assim, mais estudos e pesquisas são necessários para que se avalie a quantidade e a qualidade do osso e do ligamento periodontal formados.
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Environmental quality assessment studies have been conducted with tree species largely distributed in the Atlantic Forest. Leaf and soil samples were collected in the conservation unit Parque Estadual da Serra do Mar (PESM) nearby the industrial complex of Cubatao, Sao Paulo State, Brazil, and analyzed for chemical elements by instrumental neutron activation analysis. Results were compared to background values obtained in the Parque Estadual Carlos Botelho (PECB). The higher As, Fe, Hg and Zn mass fractions in the tree leaves of PESM indicated anthropogenic influence on this conservation unit.
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The controlled disposal of tannery sludge in agricultural soils is a viable alternative for recycling such waste; however, the impact of this practice on the arbuscular mycorrhizal fungi (AMF) communities is not well understood. We studied the effects of low-chromium tannery sludge amendment in soils on AMF spore density, species richness and diversity, and root colonization levels. Sludge was applied at four doses to an agricultural field in Rolandia, Parana state, Brazil. The sludge was left undisturbed on the soil surface and then the area was harrowed and planted with corn. The soil was sampled at four intervals and corn roots once within a year (2007/2008). AMF spore density was low (1 to 49 spores per 50 cm(3) of soil) and decreased as doses of tannery sludge increased. AMF root colonization was high (64%) and unaffected by tannery sludge. Eighteen AMF species belonging to six genera (Acaulospora, Glomus, Gigaspora, Scutellospora, Paraglomus, and Ambispora) were recorded. At the sludge doses of 9.0 and 22.6 Mg ha(-1), we observed a decrease in AMF species richness and diversity, and changes in their relative frequencies. Hierarchical grouping analysis showed that adding tannery waste to the soil altered AMF spore community in relation to the control, modifying the mycorrhizal status of soil and selectively favoring the sporulation of certain species.
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An adequate supply of nitrogen is essential for high yield of common bean seeds; however, the responses to this nutrient in no-tillage systems can vary in function of the species and the amount of straw present. The aim of this research was to evaluate response of the common bean to N in no-tillage systems over maize, millet and Brachiaria brizantha crop residues. Three experiments were conducted, one for each gramineous species. The experimental design was a randomized block in a 5x2x2 factorial scheme, with five N doses (0, 30, 60, 90, 120 kg ha(-1)), in two distinct stadia during the vegetative development (3(rd) and 6(th) trifoliate leaf) and two common bean cultivars (IPR Juriti and Perola), with four replications. The IPR Juriti produced a greater number of pods per plant and showed lower mass per 100 seeds than Perola. It did not show variation in bean yield when the sidedressing N application was carried out in the 3(rd) or 6(th) trifoliate leaf stadia. Based on the obtained results, one concludes that the seed productivity of common beans increases linearly with N doses in a no-tillage system over maize residues.
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Absence of the horizontal segment of the left portal vein (PV) or absence of bifurcation of the portal vein (ABPV) is extremely rare anomaly. The aim of this study was to study the extra-hepatic PV demonstrating the importance of its careful assessment for the purpose of split-liver transplantation. Human cadaver livers (n = 60) were obtained from routine autopsies. The cutting plane of the liver consisted of a longitudinal section made immediately on the left of the supra-hepatic inferior vena cava through the gallbladder bed preserving the arterial, portal and biliary branches in order to obtain two viable grafts (right lobe-segments V, VI, VII, and VIII and left lobe-segments II, III, and IV) as defined by the main portal scissure. The PV was dissected out and recorded for application of the liver splitting. The PV trunk has been divided into right and left branch in 50 (83.3%) cases. A trifurcation of the PV was found in 9 (15.2%) cases, 3 (5%) was a right anterior segmental PV arising from the left PV and 6 (10%) a right posterior segmental PV arising from the main PV. ABPV occurred in 1 (1.6%) case. Absence of bifurcation of the portal vein is a rare anatomic variation, the surgeon must be cautious and aware of the existence of this exceptional PV anomaly either pre or intra-operatively for the purpose of hepatectomies or even split-liver transplantation.
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Purpose We quantified variations of the lingual artery origin, measured the lingual artery origin distance from clinical relevant landmarks and compared the lingual artery diameters with normal and variable origin. Methods Forty-two formalin fixed male cadavers were bilaterally evaluated. Measurements were performed with the aid of an electronic digital caliper. Results The origin distances from the common carotid artery bifurcation was 1.05 +/- 0.11 and 1.02 +/- 0.11 cm for the right and left lingual arteries respectively with no differences compared to the lingual-facial trunks. The diameters of the lingual arteries were 0.25 +/- 0.01 and 0.26 +/- 0.01 cm for the right and left sides, respectively, while the lingual facial trunks showed diameters of 0.21 +/- 0.02 and 0.24 +/- 0.02 cm for the right and left sides, respectively. Conclusions The present study adds information on the lingual artery diameter and its anatomical relation to clinically useful landmarks.
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Background: This pilot study assessed the effect of short-duration treatment with etoricoxib as adjuvant therapy to scaling and root planing (SRP) on the clinical and radiographic parameters and prostaglandin E-2 (PGE(2)) levels in aggressive periodontitis. Methods: Subjects were randomly allocated to test or control treatment (n = 10 in each group) and submitted to SRP and treatment with etoricoxib, 120 mg/day, or placebo for 7 days. Probing depth, clinical attachment level (CAL), gingival recession, visible plaque index, bleeding on probing, linear distance (LD) from the cemento-enamel junction to the alveolar crest, and analysis of the gray levels were recorded before and 1 month after the therapies. The prostaglandin E-2 (PGE(2)) level in the gingival crevicular fluid (GCF) was measured by radioimmunoassay at the beginning of the study and 7 and 30 days after treatment. Results: No significant difference in the clinical parameters was observed between the groups at the end of the experimental period, although both groups presented significant improvement in all variables examined. There was a decrease in CAL from 5.54 +/- 0.47 mm to 3.59 +/- 0.53 mm in the test group and from 5.92 +/- 1.10 mmto 3.69 +/- 0.80 mm in the control group. A significant reduction in PGE(2) was found after 7 days of treatment. LD differed between the groups. Conclusion: Etoricoxib did not promote additional improvement in the clinical parameters; however, it produced an initial reduction in the PGE(2) levels in the GCF, which could be related to the discrete improvement in the bone condition.
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Purpose: The aim of this in vitro study was to evaluate the microtensile bond strength (mu TBS) and hybrid layer morphology of different adhesive systems, either followed by treatment with Nd:YAG laser irradiation or not. Previous studies have shown the effects of Nd:YAG laser irradiation on the dentin surface at restoration margins, but there are few reports about the significance of the irradiation on the hybrid layer. Materials and Methods: The flattened coronal and root dentin samples of 24 bovine teeth were randomly divided into 8 groups, according to the adhesive system used - Scotchbond Multi Purpose (SBMP) or Clearfil SE Bond (CSEB) - and were either irradiated with Nd:YAG or not, with different parameters: 0.8 W/10 Hz, 0.8 W/20 Hz, 1.2 W/10 Hz, 1.2 W/20 Hz. The left sides of specimens were the control groups, and right sides were irradiated. A composite crown was built over bonded surfaces and stored in water (24 h at 37 degrees C). Specimens were sectioned vertically into slabs that were subjected to mu TBS testing and observed by SEM. Results: Control groups (27.81 +/- 1.38) showed statistically higher values than lased groups (21.37 +/- 0.99), and CSEB control group values (31.26 +/- 15.71) were statistically higher than those of SBMP (24.3 +/- 10.66). There were no significant differences between CSEB (20.34 +/- 10.01) and SBMP (22.43 +/- 9.82) lased groups. Among parameters tested, 0.8 W/10 Hz showed the highest value (25.54 +/- 11.74). Nd:YAG laser irradiation caused dentin to melt under the adhesive layer of both adhesive systems tested. Conclusion: With the parameters used in this study, Nd:YAG laser irradiation of the hybrid layer promoted morphological changes in dentin and negatively influenced the bond strength of both adhesive systems.
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Metalloproteinases (MMPs) have been implicated with metabolism of collagen in physiological and pathological processes in human dentine. As bovine teeth have been used as a substitute for human teeth in laboratory analysis, this study evaluated the activity of MMP-2 and -9 in bovine versus human dentine. Bovine and human dentine fragments, from crowns and roots, were powderized. Protein extraction was performed by two protocols: a neutral extraction with guanidine-HCl/EDTA (pH 7.4) and an acidic extraction with citric acid (pH 2.3). Gelatinolytic activities of extracts were revealed by zymography. MMP-2 and -9 were detected in crown and root dentine from bovine and human teeth. Total activities of MMP-2 were 11.4 +/- 2.2, 14.6 +/- 2.0, 9.7 +/- 1.2 and 12.4 +/- 0.9 ng/ml for bovine root, human root, bovine crown and human crown dentine, respectively. Corresponding activities for MMP-9 were 14.9 +/- 2.0, 15.3 +/- 1.3, 15.4 +/- 1.3 and 15.5 +/- 1.3 ng/ml, respectively. Bovine dentine was found to be a reliable substrate for studies involving the activity of MMP-2 and -9. Copyright (C) 2011 S. Karger AG, Basel
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Genial tubercles usually are small bony protuberances on the lingual aspect of the mandible symphysis. Conversely, this case shows 3D tomographic reconstruction images of genial tubercles as an oversized projection causing pain and discomfort to the patient.
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Central giant cell granuloma (CGCG) is a benign lesion with unpredictable biological behaviour ranging from a slow-growing asymptomatic swelling to an aggressive lesion associated with pain, bone and root resorption and also tooth displacement. The aetiology of the disease is unclear with controversies in the literature on whether it is mainly of reactional, inflammatory, infectious, neoplasic or genetic origin. To test the hypothesis that mutations in the SH3BP2 gene, as the principal cause of cherubism, are also responsible for, or at least associated with, giant cell lesions, 30 patients with CGCG were recruited for this study and subjected to analysis of germ line and/or somatic alterations. In the blood samples of nine patients, one codon alteration in exon 4 was found, but this alteration did not lead to changes at the amino acid level. In conclusion, if a primary genetic defect is the cause for CGCG it is either located in SH3BP2 gene exons not yet related to cherubism or in a different gene.
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Background: Aggressive periodontitis is a specific form of periodontal disease that is characterized by rapid attachment loss and bone destruction. Cytokine profiles are of considerable value when studying disease course during treatment. The aim of this trial was to investigate cytokine levels in the gingival crevicular fluid (GCF) of patients with aggressive periodontitis, after treatment with photodynamic therapy (PDT) or scaling and root planing (SRP), in a split-mouth design on -7, 0, +1, +7, +30, and +90 days. Methods: Ten patients were randomly treated with PDT using a laser source associated with a photosensitizer or SRP with hand instruments. GCF samples were collected, and the concentrations of tumor necrosis factor-alpha (TNF-alpha) and receptor activator of nuclear factor-kappa B ligand (RANKL) were determined by enzyme-linked immunosorbent assays. The data were analyzed using generalized estimating equations to test the associations among treatments, evaluated parameters, and experimental times (alpha = 0.05). Results: Non-surgical periodontal treatment with PDT or SRP led to statistically significant reductions in TNF-alpha level 30 days following treatment. There were similar levels of TNF-alpha and RANKL at the different time points in both groups, with no statistically significant differences. Conclusion: SRP and PDT had similar effects on crevicular TNF-alpha and RANKL levels in patients with aggressive periodontitis. J Periodontol 2009;80:98-105.
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The efficient fertilizer use contend micronutrient depends, also, of the interactions that occur with some nutrients. The objective was to study the interaction of zinc with the excessively nutrient ones in function of the application of different doses and sources of Zn saw seed in the culture of the rice. The experiment was carried through in conditions of vegetation house, in the FCAV/Unesp. The used experimental delineation was entirely cazualized, with three repetitions. The treatments had been five doses: 0; 1,0; 2,0; 4,0 and 8,0 g of Zn for kg of seed; e two zinc sources; sulphate of zinc (22% of Zn) and zinc oxide (50% of Zn). The experimental unit was a translucent polyethylene tray, filled with 5 washed thick sand, where 50 seeds of rice had been sown (to var. Caiapo). To the 30 days after the sowing, effected the cut of the plants, separating them in aerial part and roots. From the results of the dry substance and text of nutrients of the aerial part and root of the rice, the accumulation of the nutrients in the respective agencies of the plants was calculated. Becoming fullfilled it variance analysis and the when necessary unfoldings. It had effect of the interactions in distinguishing way between root and aerial part of rice, with regard to the doses and sources.
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The Nd:YAG laser efficacy associated with conventional treatment for bacterial reduction has been investigated throughout literature. The purpose of this study was to evaluate the bacterial reduction after Nd:YAG laser irradiation associated with scaling and root planning in class II furcation defects in patients with chronic periodontitis. Thirty-four furcation lesions were selected from 17 subjects. The control group received conventional treatment, and the experimental group received the same treatment followed by Nd:YAG laser irradiation (100 mJ/pulse; 15 Hz; 1.5 W, 60 s, 141.5 J/cm(2)). Both treatments resulted in improvements of most clinical parameters. A significant reduction of colony forming unit (CFU) of total bacteria number was observed in both groups. The highest reduction was noted in the experimental group immediately after the treatment. The number of dark pigmented bacteria and the percentage of patients with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans reduced immediately after the treatment and returned to values close to the initial ones 6 weeks after the baseline for both groups. The Nd:YAG laser associated with conventional treatment promoted significant bacterial reduction in class II furcation immediately after irradiation, although this reduction was not observed 6 weeks after the baseline.