23 resultados para seed pathology

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Various factors affect spatial genetic structure in plant populations, including adult density and primary and secondary seed dispersal mechanisms. We evaluated pollen and seed dispersal distances and spatial genetic structure of Carapa guianensis Aublet. (Meliaceae) in occasionally inundated and terra firme forest environments that differed in tree densities and secondary seed dispersal agents. We used parentage analysis to obtain contemporary gene flow estimates and assessed the spatial genetic structure of adults and juveniles. Despite the higher density of adults (diameter at breast height >= 25 cm) and spatial aggregation in occasionally inundated forest, the average pollen dispersal distance was similar in both types of forest (195 +/- 106 m in terra firme and 175 +/- 87 m in occasionally inundated plots). Higher seed flow rates (36.7% of juveniles were from outside the plot) and distances (155 +/- 84 m) were found in terra firme compared to the occasionally inundated plot (25.4% and 114 +/- 69 m). There was a weak spatial genetic structure in juveniles and in terra firme adults. These results indicate that inundation may not have had a significant role in seed dispersal in the occasionally inundated plot, probably because of the higher levels of seedling mortality.

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(Isothermal seed germination of Adenanthera pavonina). This work reports aspects of seed germination at different temperatures of Adenanthera pavonina L., a woody Southeast Asian Leguminosae. Germination was studied by measuring the final percentages, the rate, the rate variance and the synchronisation of the individual seeds calculated by the minimal informational entropy of frequencies distribution of seed germination. Overlapping the germinability range with the range for the highest values of germination rates and the minimal informational entropy of frequencies distribution of seed germination, we found that the best temperature for the germination of A. pavonina seeds is 35 degrees C. The slope mu of the Arrhenius plot of the germination rates is positive for T < 35 degrees C and negative for T > 35 degrees C. The activation enthalpies, estimated from closely-spaced points, shows that vertical bar Delta H-vertical bar < 12 Cal mol(-1) occur for temperatures in the range between 25 degrees C and 40 degrees C. The ecological implication of these results are that this species may germinate very fast in tropical areas during the summer season. This may be an advantage to the establishment of this species under the climatic conditions in those areas.

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The objective of this study was to evaluate the genetic differences among three matrix groups of Cedrela fissilis based on quantitative juvenile variables on a progeny test to define seed collecting zones and use of seeds of this species in the study region as well as to evaluate genetic variability of the sampled material. A progeny test was established in a nursery with seeds from 48 seed trees collected in the municipalities of Rio Negrinho, Mafra and Sao Bento do Sul, state of Santa Catarina, and in the municipalities of Lapa, Rio Negro, Campo do Tenente and Antonio Olinto, state of Parana. Of the collected seed trees, 33 sampled trees were distributed in three sites and 15 trees were dispersed in the studied region. It was used a complete random block design, with 8 replicates and 20 plants per plot. Evaluated data included: emergency rate; seedling base diameter and height (61, 102 and 145 days after the seeds were sowed); seedling survival; number of leaves per seedling; aerial section dry mass and root dry mass; and the foliar area of the third fully expanded leaf measured from the apical meristem. The Maximum Restricted Likelihood Method (REML) was used, using the software SELEGEN for analysis. It was found that the juvenile characters are strongly genetically controlled and they can be used to estimate genetic variability of population samples of Cedrela fissilis. The three groups of trees spatially limited did not significantly differ among each other, allowing to conclude that the three areas are part of the same tree seed transfer zone.

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Several proteins have been isolated from seeds of leguminous, but this is the first report that a protease was obtained from seeds of Caesalpinia echinata Lam., a tree belonging to the Fabaceae family. This enzyme was purified to homogeneity by hydrophobic interaction and anion exchange chromatographies and gel filtration. This 61-kDa serine protease (CeSP) hydrolyses H-D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide (K-m 55.7 mu M) in an optimum pH of 7.1, and this activity is effectively retained until 50 degrees C. CeSP remained stable in the presence of kosmotropic anions (PO43-, SO42-, and CH3COO-) or chaotropic cations (K+ and Na+). It is strongly inhibited by TLCK, a serine protease inhibitor, but not by E-64, EDTA or pepstatin A. The characteristics of the purified enzyme allowed us to classify it as a serine protease. The role of CeSP in the seeds cannot be assigned yet but is possible to infer that it is involved in the mobilization of seed storage proteins.

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High-diversity reforestation can help jumpstart tropical forest restoration, but obtaining viable seedlings is a major constraint: if nurseries do not offer them, it is hard to plant all the species one would like. From 2007 to 2009, we investigated five different seed acquisition strategies employed by a well-established tree nursery in southeastern Brazil, namely (1) in-house seed harvesters; (2) hiring a professional harvester; (3) amateur seed harvesters; or (4) a seed production cooperative, as well as (5) participating in a seed exchange program. In addition, we evaluated two strategies not dependent on seeds: harvesting seedlings from native tree species found regenerating under Eucalyptus plantations, and in a native forest remnant. A total of 344 native tree and shrub species were collected as seeds or seedlings, including 2,465 seed lots. Among these, a subset of 120 species was obtained through seed harvesting in each year. Overall, combining several strategies for obtaining planting stocks was an effective way to increase species richness, representation of some functional groups (dispersal syndromes, planting group, and shade tolerance), and genetic diversity of seedlings produced in forest tree nurseries. Such outcomes are greatly desirable to support high-diversity reforestation as part of tropical forest restoration. In addition, community-based seed harvesting strategies fostered greater socioeconomic integration of traditional communities in restoration projects and programs, which is an important bottleneck for the advance of ecological restoration, especially in developing countries. Finally, we discuss some of the limitations of the various strategies for obtaining planting stocks and the way forward for their improvement.

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Non-destructive procedures are desirable for a precise internal seed morphology assessment. In this research the efficiency of X-ray densitometry for internal seed morphology analysis and physical quality of squash, melon and watermelon was evaluated. Seeds were submitted to X-ray densitometry and a typical density profile for each seed was generated. Based on the detailed densitometry profiles it was possible indicate density values for specific seed regions of the seeds and identify causes of poor germination. X-ray densitometry was considered as a promising non-destructive procedure to evaluate internal seed morphology of squash, melon and watermelon and demonstrated a strong potential for further research in seed testing.

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Diatraea saccharalis, is a major sugarcane pest, causing damage to the stalks of sugarcane plants. In this study, a trypsin inhibitor (ApTI) was purified from Adenanthera pavonina seeds and was tested for its insect growth regulatory effect. ApTI showed a dose-dependent effect on average larval weight and survival. 0.1% ApTI produced approximately 67% and 50% decreases in weight and survival larval, respectively. The results from dietary utilization experiments with D. saccharalis larvae showed a reduction in the efficiency of conversion of ingested food and digested food, and an increase in approximate digestibility and metabolic cost. The level of trypsin was significantly decreased (ca. 55%) in the midgut of larvae reared on a diet containing 0.05% ApTI and the trypsin activity in ApTI-fed larvae demonstrated sensitivity to ApTI. The action of ApTI on the development of D. saccharalis larvae shows that this protein may have great toxic potential. (C) 2011 Elsevier Ltd. All rights reserved.

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Calcium (Ca) and boron (B) have been reported as the major macro-and micronutrient required for castor bean plant yield. The objective of this study was to determine the Ca: B ratios (in the growth media and plant tissue) for fruit yield and shoot dry weight of the castor bean (Ricinus communis L.), grown in a nutrient solution, and to evaluate Ca and B supply on concentration and total uptake of Ca, potassium (K), magnesium (Mg), and B, as well on the seed oil content. The treatments were arranged in a 3 x 3 factorial fashion, consisting of three rates of Ca (40, 80, and 160 mg L-1) and three of B (0.32, 0.96, and 1.60 mg L-1). Calcium and B rates increased the shoot and root dry weight and fruit yield at a Ca: B ratio in the nutrient solution of 166 and 100, respectively. Symptoms of B deficiency were observed in plants supplied with 0.32 mg B L-1, regardless of the Ca concentration in the nutrient solution. Plants which showed visual symptoms of Ca deficiency cultivated with 40 mg Ca L-1 presented concentration of Ca in plant tissue up to 10 g kg(-1). The concentration and total Ca and B uptake increased with the rates of them. Notwithstanding, the shoot Ca accumulation was improved by B rates. In addition, there were no decreases in K and Mg uptake due to Ca rates. Furthermore, addition of 80 mg L-1 of Ca and 1.60 mg L-1 of B in the growth media increased the seed oil content. The Ca: B ratio in the diagnostic leaf associated with the highest plant dry weight (shoot and root) and fruit yield, was 500 (16 to 20 g kg(-1) of Ca, and for 30 to 40 mg kg(-1) of B).

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Cirrhosis is a moiphologic term that has been used for almost 200 years to denote the end stage of a variety of chronic liver diseases. The term implies a condition with adverse prognosis due to the well-known complications of portal hypertension, hepatocellular carcinoma, and liver failure. However, recent advances in the diagnosis and treatment of chronic liver diseases have changed the natural history of cirrhosis significantly. This consensus document by the International Liver Pathology Study Group challenges the usefulness of the word cirrhosis in modern medicine and suggests that this is an appropriate time to consider discontinuing the use of this term. The role of pathologists should evolve to the diagnosis of advanced stage of chronic liver disease, with emphasis on etiology, grade of activity, features suggestive of progression or regression, presence of other diseases, and risk factors for malignancy, within the perspective of an integrated clinicopathologic assessment.

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Questions What are the main features of the seed rain in a fragmented Atlantic forest landscape? Can seed rain species attributes (life form, dispersal mode, successional status) relate to the spatial arrangement (size and number of fragments, edge density and presence of corridor) of forest fragments in the landscape? How does the rain forest landscape structure affect the seed rain? Location Atlantic rainforest, Sao Paulo State, Southeastern Brazil. Methods Seed rain samples were collected monthly throughout 1yr, counted, identified and classified according to species dispersal mode, successional status and life form. Seed rain composition was compared with woody species near the seed traps. Relationships between seed rain composition and landscape spatial arrangement (fragment area, presence of corridor, number of fragments in the surroundings, proximity of fragments, and edge density) were tested using canonical correspondence analysis (CCA). Results We collected 20142 seeds belonging to 115 taxa, most of them early successional and anemochorous trees. In general, the seed rain had a species composition distinct from that of the nearby forest tree community. Small isolated fragments contained more seeds, mainly of anemochorous, epiphytic and early-successional species; large fragments showed higher association with zoochorous and late-successional species compared to small fragments. The CCA significantly distinguished the species dispersal mode according to fragment size and isolation, anemochorous species being associated to small and isolated fragments, and zoochorous species to larger areas and fragment aggregation. Nevertheless, a gradient driven by proximity (PROX) and edge density (ED) segregated lianas (in the positive extremity), early successional and epiphyte species (in the negative end); large fragments were positively associated to PROX and ED. Conclusions The results highlight the importance of the size and spatial arrangement of forest patches to promote habitat connectivity and improve the flux of animal-dispersed seeds. Landscape structure controls seed fluxes and affects plant dispersal capacity, potentially influencing the composition and structure of forest fragments. The seed rain composition may be used to assess the effects of landscape spatial structure on plant assemblages, and provide relevant information for biodiversity conservation.

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This study describes the hypocholesterolaemic effect of whole lupin and its protein in hamsters. The diets were: casein (control group HC), lupin protein isolate (group HPI) and whole lupin seed (group HWS). Diets from HPI and HWS promoted a significant reduction of total cholesterol and non-HDL cholesterol in the hamsters' plasma as compared with HC. The true digestibility of HPI and HC groups were similar and differed significantly from the HWS one, which in turn showed a significant difference in total sterol excretion as compared to the former groups. Histological analysis of the liver revealed that animals fed on HPI and HWS diets presented a low level of steatosis (level 1) as compared to the ones fed on HC diet (level 4). Our findings demonstrate that protein isolate from Lupinus albus from Brazil has a metabolic effect on endogenous cholesterol metabolism and a protector effect on development of hepatic steatosis. (C) 2011 Elsevier Ltd. All rights reserved.

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We sought to evaluate the performance of diagnostic tools to establish an affordable setting for early detection of cervical cancer in developing countries. We compared the performance of different screening tests and their feasibility in a cohort of over 12,000 women: conventional Pap smear, liquid-based cytology, visual inspection with acetic acid (VIA), visual inspection with Iodine solution (VILI), cervicography, screening colposcopy, and high-risk human papillomavirus (HPV) testing (HR-HPV) collected by physician and by self-sampling. HR-HPV assay collected by the physician has the highest sensitivity (80 %), but high unnecessary referrals to colposcopy (15.1 %). HR-HPV test in self-sampling had a markedly lower (57.1 %) sensitivity. VIA, VILI, and cervicography had a poor sensitivity (47.4, 55, and 28.6 %, respectively). Colposcopy presented with sensitivity of 100 % in detecting CIN2+, but the lowest specificity (66.9 %). Co-testing with VIA and VILI Pap test increased the sensitivity of stand-alone Pap test from 71.6 to 87.1 % and 71.6 to 95 %, respectively, but with high number of unnecessary colposcopies. Co-testing with HR-HPV importantly increased the sensitivity of Pap test (to 86 %), but with high number of unnecessary colposcopies (17.5 %). Molecular tests adjunct to Pap test seems a realistic option to improve the detection of high-grade lesions in population-based screening programs.

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Background: Placental malaria (PM) is one major feature of malaria during pregnancy. A murine model of experimental PM using BALB/c mice infected with Plasmodium berghei ANKA was recently established, but there is need for additional PM models with different parasite/host combinations that allow to interrogate the involvement of specific host genetic factors in the placental inflammatory response to Plasmodium infection. Methods: A mid-term infection protocol was used to test PM induction by three P. berghei parasite lines, derived from the K173, NK65 and ANKA strains of P. berghei that fail to induce experimental cerebral malaria (ECM) in the susceptible C57BL/6 mice. Parasitaemia course, pregnancy outcome and placenta pathology induced by the three parasite lines were compared. Results: The three P. berghei lines were able to evoke severe PM pathology and poor pregnancy outcome features. The results indicate that parasite components required to induce PM are distinct from ECM. Nevertheless, infection with parasites of the ANKA Delta pm4 line, which lack expression of plasmepsin 4, displayed milder disease phenotypes associated with a strong innate immune response as compared to infections with NK65 and K173 parasites. Conclusions: Infection of pregnant C57BL/6 females with K173, NK65 and ANKA Delta pm4 P. berghei parasites provide experimental systems to identify host molecular components involved in PM pathogenesis mechanisms.

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FAPESP (BIOTA Program) [2007/03392-6, 2010/04927-3]

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Rationale and aim: This paper has the object to present the impact of nuts' and seeds' injuries withdrawing data from the Susy Safe registry, highlighting that as for other foreign bodies the main item efficiently and substantially susceptible to changes to decrease the accidents' rates is the education of adults and children, that can be shared with parents both from pediatricians and general practitioners. Indeed labeling and age related warnings have also a fundamental relevance in prevention. Methods: The present study draws its data from the Susy Safe registry. Details on injuries are entered in the Susy Safe Web-registry through a standardized case report form, that includes information regarding: children age and gender, features of the object, circumstances of injury (presence of parents and activity) and hospitalization's details (lasting, complications and removal details). Cases are prospectively collected using the Susy Safe system from 06/2005; moreover, also information regarding past consecutive cases available in each centre adhering to the project have been entered in the Susy Safe registry. Results: Nuts and seeds are one of the most common food item retrieved in foreign bodies injuries in children. In Susy Safe registry they represent the 38% in food group, and almost the 10% in general cases. Trachea, bronchi and lungs were the main location of FB's retrieval, showing an incidence of 68%. Hospitalization occurred in 83% of cases, showing the major frequency for foreign bodies located in trachea. This location was also the principal site of complications, with a frequency of 68%. There were no significant associations between these outcomes and the age class of the children. The most common complications seen (22.4%) was bronchitis, followed by pneumonia (19.7%). Adult presence was recorded as positive in 71.2% of cases, showing an association (p value 0.009) between the adult supervision and the hospitalization outcome. On the contrary there was a non significant association between adult presence and the occurrence of complications. In 80.7% of cases, the incident happened while the child was eating. Among those cases, 88.6% interested trachea, lungs and bronchi. Conclusions: Food-related aspiration injuries are common events for young children, particularly under 4 years of age, and may lead to severe complication. There is a need to study in more depth specific characteristics of foreign bodies associated with increased hazard, such as size, shape, hardness or firmness, lubricity, pliability and elasticity, in order to better identify risky foods, and more precisely described the pathogenetic pathway. Parents are not adequately conscious and aware toward this risk; therefore, the number and severity of the injuries could be reduced by educating parents and children. Information about food safety should be included in all visits to pediatricians in order to make parents able to understand, select, and identify key characteristics of hazardous foods and better control the hazard level of various foods. Finally, preventive measures including warning labels on high-risk foods could be implemented. (C) 2012 Elsevier Ireland Ltd. All rights reserved.