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141.
Priscilla Patrocínio Abreu Margarete Magalhães Souza Eileen Azevedo Santos Marcel Viana Pires Mônica Moura Pires Alex-Alan Furtado de Almeida 《Euphytica》2009,166(3):307-315
The Passiflora L. (Passifloraceae) genus consists of about 500 species widely distributed throughout tropical and subtropical regions, commonly
known as the passion flower. The passion flowers are considered ornamental plants because of the exotic beauty of their flowers
and variant foliage. Since their introduction to the Old World, around 1625, seventeenth century, they have been used to decorate
European glasshouses and gardens. Interspecific hybridization is used to produce single ornamental plants. However in some
countries, such as Brazil, being centre of origin of many species, the potential value of these species has hardly been exploited.
The beauty of these wild species and their hybrids is little known in Brazil. Therefore it is here intended to highlight the
productive and commercial potential of the passion flowers for the purpose to generate an income in family agriculture, while
maintaining the ecological balance and optimizing the use of natural resources. 相似文献
142.
Rodrigo Favreto Ricardo Silva Pereira Mello Luís Rios de Moura Baptista 《Agroforestry Systems》2010,80(2):303-313
The palm Euterpe edulis has high ecological and economic importance in Brazil. Currently, this species is being cultivated and managed for spontaneous
regeneration in banana plantations. However, there are no data comparing its plantation growth performance to its native forest
growth. We evaluated growth and mortality (M) of individuals of E. edulis planted in secondary dense ombrophilous forest and in banana plantations, as well as their relationships with site variables
(canopy opening, soil nutrient availability, density of existing E. edulis, and herbivory). Twelve banana plantation sites and 12 sites in secondary dense ombrophilous forests were selected. At each
site, 25 young individuals of E. edulis were planted in 2003. Annually until 2008, morphometric, herbivory, and M of the individuals were evaluated. In 2008, canopy
and soil variables were measured at each plot. E. edulis growth was five times higher in banana plots compared to forest plots; current annual increment on height reached 38.9 cm
in banana plots, compared to 7.3 cm in forest plots. M was relatively low and similar at both sites, presenting an intraspecific
density-dependence pattern. Significant correlations were found between morphometric variables, M, and herbivory of E. edulis and canopy and soil variables. Euterpe edulis presented plasticity that allows for its establishment in banana plantations, indicating high potential for management in
agroforestry consortia. Such management may be a useful conservation strategy for this and other shade-tolerant species. 相似文献
143.
CEA Souza AA Araújo JTA Oliveira AC Lima Souza JNM Neiva AA Moura 《Reproduction in domestic animals》2010,45(4):644-653
We have investigated the reproductive development of the tropically adapted Santa Inês ram, the most common hair sheep in Brazil. From 8 to 48 weeks of age, 16 animals were evaluated for body and testis growth, semen parameters, testosterone concentrations and seminal plasma proteins, using two‐dimensional SDS‐PAGE. Animals were weaned at 30 days and kept in feedlots thereafter, receiving hay, concentrate (18% of crude protein) and mineral supplement. Body weight increased from 12.3 ± 0.7 to 54.3 ± 1.6 kg between 8 and 48 weeks (p < 0.05), but changes in thoracic perimeter and scrotal circumference were non‐significant after 36 weeks (p > 0.05). The percentage of motile sperm increased slowly until 23 weeks and more rapidly after that age, but significant changes in progressive motility occurred after 25 weeks. Presence of abnormal sperm related inversely to age. Most significant changes in sperm concentration occurred between 38 and 44 weeks (0.38 ± 0.05 to 1.14 ± 0.24 × 109 cells/ml, p < 0.05) and testosterone reached its highest concentrations at 42 weeks, decreasing afterwards. Rams reached puberty at 28.2 ± 0.8 weeks. The number of protein spots on seminal plasma gels was similar from 15 to 18 weeks (45 and 47 spots; p > 0.05), increased until 24 weeks (141 spots) and 28 weeks (170 spots; p < 0.05) and remained without significant (p > 0.05) changes from 28 to 48 weeks (186 ± 10 spots). Furthermore, the intensity of selected spots on 2D maps increased (p < 0.05) between 15 and 28 weeks, which preceded or coincided with the main developmental changes in sperm motility and percentage of defective sperm in the ejaculates. These results will support future studies designed to characterize specific seminal plasma proteins whose expression relate to the development of testis, epididymis and accessory sex glands. 相似文献
144.
Brachiola algerae, a parasite of Anopheles mosquitoes, has also been isolated from a human cornea, a cutaneous nodule and deep muscle tissue. All three human isolates of B. algerae are morphologically, serologically, and genetically similar to the mosquito-derived isolates including the original isolate of Vavra and Undeen. All of these isolates grew well in mammalian cell cultures at 37 degrees C and produced spores. Transmission electron microscopy revealed that all developmental stages including meronts, sporoblasts and spores were diplokaryotic and developed in direct contact with the host cell cytoplasm, a feature characteristic of the genus Brachiola. Spores of all isolates reacted well, in the immunofluorescence assay, with the rabbit anti-B. algerae serum. In the immunoblot assay, although the overall banding patterns of the human and mosquito isolates were similar, minor differences could be discerned. Sequencing of the PCR products of the amplified SSU rRNA gene revealed the existence of two distinct genotypes; the original mosquito (Undeen) isolate belonged to genotype 1 and the isolate from cornea and that from the deep muscle biopsy to genotype 2, whereas the isolates from a mosquito and one of the other two human isolates (one from skin abscess) had both genotypes, 1 and 2. It is known that spores of mosquito-derived B. algerae can not only proliferate in mammalian cell cultures at 37 degrees C but also can infect mice when injected into footpads or deposited on the corneal surface. These observations indicate that the spores have potential to be a risk factor for humans, especially those with immunodeficiency. 相似文献
145.
Thyrocalcitonin has been suspected of containing iodine, because its analytical behavior and method of extraction are similar to that of iodinated peptides. The iodine content of increasingly pure thyrocalcitonin extracts was determined by two methods, Kolthoff's procedure and activation analysis, with good agreement. A possible link between calcium and iodine metabolism is suggested by these findings. 相似文献
146.
P. Moura S. Marques L. Alves J.P.B. Freire L.F. Cunha M.P. Esteves 《Livestock Science》2007,108(1-3):244-248
The effect of xylo-oligosaccharides (XOS), a probiotic culture of Saccharomyces cerevisiae (SC) and the combined administration of XOS and SC on the piglet intestinal microbiota was investigated. Twenty four weaned piglets were fed during 4 weeks with one of the following diets: (BD) basal diet; (BD + XOS) basal diet supplemented with xylo-oligosaccharides (20 g kg− 1); (BD + SC) basal diet supplemented with S. cerevisiae (6 × 109 CFU kg− 1); and (BD + XOS + SC) basal diet supplemented with xylo-oligosaccharides and S. cerevisiae. Samples from the ileum, caecum and colon were collected and analysed for total anaerobes growing in XOS or glucose, xylose and arabinose (GXA) containing media. Specific primers were used to evaluate differences in Bifidobacterium and Lactobacillus populations and ERIC PCR to fingerprint the intestinal microbiota.
The lowest number of culturable bacteria was obtained from the ileum of animals fed BD + XOS. The highest PCR titres with Lactobacillus group-specific primers in BD and BD + SC were obtained in the caecal contents. In XOS-supplemented diets the PCR titres were increased or maintained, from the caecum to the colon. Bifidobacteria were not detected in any samples using genus-specific primers. In the dendrogram from ERIC PCR, the piglets fed with XOS diets presented the highest similarity between samples and probiotic reference strains. 相似文献
147.
Freitas DR Rosa RM Moura DJ Seitz AL Colodel EM Driemeier D Da Silva Vaz I Masuda A 《Veterinary parasitology》2007,144(3-4):321-327
Programmed cell death (PCD) is present during the development of multicellular organisms and occurs from embryogenesis to death. In females of Boophilus microplus, the mass of several organs is reduced after the detachment from the host. In order to better characterize the cell death process that eliminates unnecessary tissues, the degeneration of salivary glands, ovaries and synganglia was investigated using DNA fragmentation in agarose gel, comet and TUNEL assays, and apoptosis activation pathway by the caspase assay. DNA fragmentation and enzymatic activity of caspase-3 were observed in salivary glands and ovaries at 48 and 72h after tick removal from the host; in synganglia these parameters were maintained at low levels upon 48h. The results obtained suggest that there is a refined control of tissue maintenance through apoptosis. 相似文献
148.
Failla ML Chitchumroonchokchai C Siritunga D De Moura FF Fregene M Manary MJ Sayre RT 《Journal of agricultural and food chemistry》2012,60(15):3861-3866
Cassava is a root crop that serves as a primary caloric source for many African communities despite its low content of β-carotene (βC). Carotenoid content of roots from wild type (WT) and three transgenic lines with high βC were compared after cooking and preparation of nonfermented and fermented flours according to traditional African methods. The various methods of processing all decreased βC content per gram dry weight regardless of genotype. The greatest loss of βC occurred during preparation of gari (dry fermentation followed by roasting) from WT and transgenic lines. The quantities of βC in cooked transgenic cassava root that partitioned into mixed micelles during in vitro digestion and transported into Caco-2 cells were significantly greater than those for identically processed WT root. These results suggest that transgenic high βC cassava will provide individuals with greater quantities of bioaccessible βC. 相似文献
149.
Moura FT Oliveira AS Macedo LL Vianna AL Andrade LB Martins-Miranda AS Oliveira JT Santos EA de Sales MP 《Journal of agricultural and food chemistry》2007,55(2):260-266
Chitin-binding vicilin from Enterolobium contortisiliquum seeds was purified by ammonium sulfate followed by gel filtration on Sephacryl 300-SH and on Sephacryl 200-SH. The vicilin, called EcV, is a dimeric glycoprotein composed of 1.03% carbohydrates and a Mr of 151 kDa, consisting of two subunits of Mr of 66.2 and 63.8 kDa. The EcV homogeneity was confirmed in a PAGE where it was observed to be a unique acid protein band with slow mobility in this native gel. E. contortisiliquum vicilin (EcV) was tested for anti-insect activity against C. maculatus and Zabrotes subfasciatus larvae and for phytopathogenic fungi, F. solani and C. lindemuntianum. EcV was very effective against both bruchids, producing 50% mortality for Z. subfasciatus at an LD50 of 0.43% and affected 50% of the larvae mass with an ED50 of 0.65%. In artificial diets given to C. maculatus, 50% of the larvae mass was affected with an ED50 of 1.03%, and larva mortality was 50% at LD50 of 1.11%. EcV was not digested by midgut homogenates of C. maculatus and Z. Subfasciatus until 12 h of incubation, and at 24 h EcV was more resistant to Z. subfasciatus larval proteases. The binding to chitin present in larvae gut associated to low EcV digestibility could explain its lethal effects. EcV also exerted an inhibitory effect on the germination of F. solani at concentrations of 10 and 20 microg mL-1. The effect of EcV on fungi is possibly due to binding to chitin-containing structures of the fungal cell wall. 相似文献
150.
Luis Otavio Brito Luis Alejandro Vinatea Arana Roberta Borda Soares William Severi Rayzza Helena Miranda Suzianny Maria Bezerra Cabral da Silva Maria Raquel Moura Coimbra Alfredo Olivera Gálvez 《Aquaculture International》2014,22(5):1649-1664
A 28-day indoor trial was conducted to evaluate the water quality, phytoplankton composition and growth of Litopenaeus vannamei in an integrated biofloc system with Gracilaria birdiae and Gracilaria domingensis. The experimental design was completely randomized with three treatments: control (shrimp monoculture); SB (shrimp and G. birdiae) and SD (shrimp and G. domingensis), all with three replicates. Random sampling was done (6 % of total population per experimental unit) to confirm white spot syndrome Virus (WSSV) infection using nested-PCR analysis due to suspicion of presence of the virus in the experiment (treatment and control groups). Shrimp L. vannamei (2.63 ± 0.10 g) were stocked in experimental tanks at a density of 425 shrimp m?3, and the Gracilaria was stocked at a biomass of 2.0 kg m?3. Shrimp mortality began in both the experimental and control groups at 10 days of culture. The integrated biofloc system (shrimp and seaweed) increased settleable solids (by 26–52 %); final weight (by 6–21 %); weekly growth (by 17–43 %); weight gain (by 17–43 %); specific growth rate (by 16–36 %); and yield (by 5–7 %) and decreased feed conversion ratio (by 21–28 %) and Cyanobacteria density about 16 % as compared to the control (shrimp monoculture). The use of red seaweed Gracilaria in an integrated biofloc system can enhance shrimp growth and reduce Cyanobacteria density in the presence of WSSV. 相似文献