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11.
Proteins from two species of the genusArtocarpus (A. integrifolia L. andA. incisa L.) were compared by ammonium sulphate fractionation, molecular sieve chromatography and SDS-polyacrylamide gel electrophoresis,
with special attention to the lectins. The protein content and hemagglutinating activity were markedly different in the two
seeds. The protein pattern obtained by both molecular sieve chromatography and SDS-polyacrylamide gel electrophoresis were
quite different. The only similarities found were the elution volume of the lectins in the Sephadex G-100 column and the lectin
bands (11 500 and 15 000 daltons) in SDS-polyacrylamide gel electrophoresis. 相似文献
12.
Filipe Pereira Cláudia Moreira Luís Fonseca Barbara van Asch Manuel Mota Isabel Abrantes António Amorim 《PloS one》2013,8(2)
The pinewood nematode, Bursaphelenchus xylophilus, is one of the greatest threats to coniferous forests worldwide, causing severe ecological damage and economic loss. The biology of B. xylophilus is similar to that of its closest relative, B. mucronatus, as both species share food resources and insect vectors, and have very similar morphological characteristics, although little pathogenicity to conifers has been associated with B. mucronatus. Using both nuclear and mitochondrial DNA markers, we show that B. xylophilus and B. mucronatus form distinct phylogenetic groups with contrasting phylogeographic patterns. B. xylophilus presents lower levels of intraspecific diversity than B. mucronatus, as expected for a species that evolved relatively recently through geographical or reproductive isolation. Genetic diversity was particularly low in recently colonised areas, such as in southwestern Europe. By contrast, B. mucronatus displays high levels of genetic diversity and two well-differentiated clades in both mitochondrial and nuclear DNA phylogenies. The lack of correlation between genetic and geographic distances in B. mucronatus suggests intense gene flow among distant regions, a phenomenon that may have remained unnoticed due to the reduced pathogenicity of the species. Overall, our findings suggest that B. xylophilus and B. mucronatus have different demographic histories despite their morphological resemblance and ecological overlap. These results suggest that Bursaphelenchus species are a valuable model for understanding the dispersion of invasive species and the risks posed to native biodiversity and ecosystems. 相似文献
13.
Felipe F.D. Oliveira Diego C.B.D. Santos Alexandre A.M. Lapis José R. Corrêa Alexandre F. Gomes Fabio C. Gozzo Paulo F. Moreira Virgínia C. de Oliveira Frank H. Quina Brenno A.D. Neto 《Bioorganic & medicinal chemistry letters》2010,20(20):6001-6007
Newly designed 2,1,3-benzothiadiazole-containing fluorescent probes with four excited state intramolecular proton transfer (ESIPT) sites were successfully tested in live cell-imaging assays using a confluent monolayer of human stem-cells (tissue). All tested dyes were compared with the commercially available DAPI and gave far better results. 相似文献
14.
Nunney L Yuan X Bromley R Hartung J Montero-Astúa M Moreira L Ortiz B Stouthamer R 《PloS one》2010,5(11):e15488
Invasive diseases present an increasing problem worldwide; however, genomic techniques are now available to investigate the timing and geographical origin of such introductions. We employed genomic techniques to demonstrate that the bacterial pathogen causing Pierce's disease of grapevine (PD) is not native to the US as previously assumed, but descended from a single genotype introduced from Central America. PD has posed a serious threat to the US wine industry ever since its first outbreak in Anaheim, California in the 1880s and continues to inhibit grape cultivation in a large area of the country. It is caused by infection of xylem vessels by the bacterium Xylella fastidiosa subsp. fastidiosa, a genetically distinct subspecies at least 15,000 years old. We present five independent kinds of evidence that strongly support our invasion hypothesis: 1) a genome-wide lack of genetic variability in X. fastidiosa subsp. fastidiosa found in the US, consistent with a recent common ancestor; 2) evidence for historical allopatry of the North American subspecies X. fastidiosa subsp. multiplex and X. fastidiosa subsp. fastidiosa; 3) evidence that X. fastidiosa subsp. fastidiosa evolved in a more tropical climate than X. fastidiosa subsp. multiplex; 4) much greater genetic variability in the proposed source population in Central America, variation within which the US genotypes are phylogenetically nested; and 5) the circumstantial evidence of importation of known hosts (coffee plants) from Central America directly into southern California just prior to the first known outbreak of the disease. The lack of genetic variation in X. fastidiosa subsp. fastidiosa in the US suggests that preventing additional introductions is important since new genetic variation may undermine PD control measures, or may lead to infection of other crop plants through the creation of novel genotypes via inter-subspecific recombination. In general, geographically mixing of previously isolated subspecies should be avoided. 相似文献
15.
Luiz Henrique Soares de Andrade Wilson Max Almeida Monteiro de Moraes Eduardo Hiroshi Matsuo Junior Elizabeth de Orleans Carvalho de Moura Hanna Karen Moreira Antunes Jairo Montemor Ednei Luiz Antonio Danilo Sales Bocalini Andrey Jorge Serra Paulo José Ferreira Tucci Patricia Chakur Brum Alessandra Medeiros 《Molecular and cellular biochemistry》2015,402(1-2):193-202
16.
A. I. Rodarte-Morales G. Feijoo M. T. Moreira J. M. Lema 《World journal of microbiology & biotechnology》2011,27(8):1839-1846
Today, more than 3,000 pharmaceutical and personal care products (PPCPs) are used and released into the environment at low
doses but they are barely degraded in wastewater treatment plants. One of the potential alternatives to effectively degrade
PPCPs is based on the use of white-rot fungi (WRF) and involves the oxidative action of extracellular fungal enzymes. The
aim of this work is to study the potential ability of three WRF strains, an anamorph species of Bjerkandera sp. R1, Bjerkandera adusta and Phanerochaete chrysosporium, to degrade PPCPs belonging to different therapeutic groups: anti-depressants (citalopram and fluoxetine), antibiotics (sulfamethoxazole),
anti-inflammatory drugs (diclofenac, ibuprofen and naproxen), anti-epileptics (carbamazepine), tranquilizers (diazepam) and
fragrances (celestolide, galaxolide and tonalide). The results reported complete degradation of all the PPCPs except for fluoxetine
and diazepam, which were partially removed in percentages from 23 to 57%. In the case of fragrances, these compounds were
neither detected in the fungal cultures nor in the abiotic controls, indicating the possibility of volatilization during the
experiment. 相似文献
17.
18.
In this work a model envisaging the integrated optimization of bioreaction and downstream processing is presented. This model extends the work presented in part 1 of this pair of papers by adding ultrafiltration to process optimization. The new operational parameters include ultrafiltration time, pressure, and stirring rate. For global optimization, the model uses as constraints the final product titer and quality to be achieved after downstream processing. This extended model was validated with the same system used in part 1, i.e., PA317 cells producing a recombinant retrovirus containing the LacZ gene as a marker in stirred tanks using porous supports. Optimization of the extended model led to the conclusion that bioreaction should have two steps, batch and perfusion, similar to what was found in part 1. Ultrafiltration in a stirred cell should be performed at low pressures and stirring rates to reduce the losses of infective retroviruses. Sensitivity analysis performed on the results of the integrated optimization showed that under optimal conditions the productivity is less sensitive to the parameters related to ultrafiltration than to those associated with bioreaction. These results were interpreted as reflecting the high yield of ultrafiltration (90%). The relevance of the model extension to perform integrated optimization was also demonstrated since a restriction in the specific ultrafiltration area in downstream processing conditioned perfusion duration and perfusion rate in bioreaction. This clearly indicates that overall process optimization cannot be achieved without integrated optimization. 相似文献
19.
Maria Ieda Siqueira Linhares Yoshito Eizuru Gildete Patriota de Andrade Ivailda Barbosa Fonseca Luiz Bezerra Carvalho Ivanildo Tenorio Moreira Yoichi Minamishima 《Microbiology and immunology》1994,38(6):475-478
The seroprevalence of human T cell leukemia virus type 1 (HTLV-1) infection was investigated in Brazilians (570): native inhabitants (298) and descendants from Japanese (272) living in Recife and its neighborhoods—North-east of Brazil. Furthermore, polytransfused renal transplanted patients (54) were also examined for the serological status to this virus. The seropositivity to HTLV-1, screened by enzyme-linked immunosorbent assay (ELISA), was low: 1.34% for the local population and 0.73% for the descendants from Japanese. However, the seropositivity for the renal transplanted patients was found to be 11.1%. This higher value suggests that this retrovirus infection seems to be of importance in this clinical condition. 相似文献
20.
Hemiodus iratapuru, a new species of the Hemiodontidae from the Rio Iratapuru, a left bank tributary of the Rio Jari, Amazon Basin, Brazil, is described. The new species is diagnosed from other species of Hemiodus by modifications in the ectopterygoid, tooth form, scale counts, dorsal‐fin form and colour pattern. The new species is proposed to be related to the Hemiodus quadrimaculatus species group. 相似文献