Genes similar to naphthalene dioxygenase genes in trifluralin-degrading bacteria     

Bellinaso Mde L  Henriques JA  Gaylarde CC  Greer CW 《Pest management science》2004,60(5):474-478

Trifluralin (alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine) is a dinitroaniline compound which was first produced in the 1960s and has been used extensively as an agricultural herbicide. There are a few publications on the biodegradation of this xenobiotic compound, but to our knowledge nothing has been documented on the genetic aspects of its catabolism. In this article, we report the analysis of DNA isolated from bacteria previously shown to degrade trifluralin, using as probes the catabolic genes ndoB, todC, xyIX, catA and xyIE which encode the enzymes naphthalene 1,2-dioxygenase, toluene dioxygenase, toluate 1,2-dioxygenase, catechol 1,2-dioxygenase and catechol 2,3-dioxygenase respectively. Using PCR and hybridization analysis, the strong hybridization of the ndoB gene with DNA extracted from four trifluralin-degrading isolates was demonstrated, although none of them was able to degrade naphthalene, as indicated by the 'clear zone' test. The results indicated the presence in these bacteria of a dioxygenase gene, whose product could act on trifluralin as its principal substrate, or fortuitously, by cometabolism. This is the first publication on genes in trifluralin-degrading bacteria.  相似文献   

The use of low‐dose metronomic chemotherapy in dogs—insight into a modern cancer field          下载免费PDF全文

T. B. Gaspar  J. Henriques  L. Marconato  F. L. Queiroga 《Veterinary and comparative oncology》2018,16(1):2-11

The era of chemotherapy, which started in the middle of the last century, has been ruled by the routine use of dose‐intense protocols, based on the “maximum‐tolerated dose” concept. By promoting a balance between patient's quality of life and the goal of rapidly killing as many tumour cells as possible, these protocols still play a prominent role in veterinary oncology. However, with the opening of a new millennium, metronomic chemotherapy (MC) started to be considered a possible alternative to traditional dose‐intense chemotherapy. Characterized by a long‐term daily administration of lower doses of cytotoxic drugs, this new modality stands out for its unique combination of effects, namely on neovascularization, immune response and tumour dormancy. This article reviews the rationale for treatment with MC, its mechanism of action and the main studies conducted in veterinary medicine, and discusses the key challenges yet to be solved.  相似文献   

Handbook of Veterinary Drugs     

AT Hart 《Australian veterinary journal》1999,77(12):783-783

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Assessment of neuropeptide binding sites and the impact of biostable kinin and CAP2b analogue treatment on aphid (Myzus persicae and Macrosiphum rosae) stress tolerance     

Lucy Alford  Richard Marley  Anthony Dornan  Jean‐Sbastien Pierre  Julian AT Dow  Ronald J Nachman  Shireen A Davies 《Pest management science》2019,75(6):1750-1759

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Response of tomato (Solanum L. section Lycopersicon Mill.) germplasm to begomovirus inoculation under controlled and field conditions     

Jorge González Aguilera  Francisco Dueñas Hurtado  Roberto Ramos Sobrinho  Victor de Souza Almeida  Sheila S. Tavares  Carlos Nick  Marcelo Oliveira Soares  Cesar A. Diniz Xavier  Renata Dias de Freitas  Martha Alvarez Gil  Francisco Murilo Zerbini  Derly J. Henriques da Silva 《Genetic Resources and Crop Evolution》2014,61(2):435-450

Ninety-five tomato accessions belonging to the Vegetable Crops Germplasm Bank of the Federal University of Viçosa (BGH-UFV) were evaluated in a protected environment (biolistic inoculation under greenhouse conditions) and in the field (natural infection) for resistance to bipartite begomoviruses present in Brazil. Plants were assessed by the visual evaluation of symptoms, and viral infection was confirmed by non-radioactive molecular hybridization. Univariate statistical analyses and correlations were made between the traits. High and significant correlations were found between the percentages of visual symptoms and of viral replication, with values of 0.67 in the protected environment and 0.60 in the field. We concluded that under the protected environment, the accessions BGH-2144, BGH-2150, BGH-6878 and BGH-6881 displayed resistance to infection. Under field conditions with natural infection, the best results were obtained for the accessions BGH-2080 and BGH-6881. Only the BGH-6881 (Solanum peruvianum L.) accession excelled in both conditions; this resistance was attributed to the presence of the Ty-2 and Ty-3 resistance gene alleles in heterozygosity. In general, all of the accessions selected in both experimental conditions can serve as sources for the development of cultivars tolerant or resistant to the bipartite begomoviruses present in Brazil.  相似文献   

Microbiology. A pathogen attacks while keeping up defense     

Normark S  Nilsson C  Normark BH 《Science (New York, N.Y.)》2005,307(5713):1211-1212

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Metal contamination in leaves and fruits of holm-oak (Quercus rotundifolia Lam.) trees growing in a pyrites mining area at Aljustrel,Portugal     

José Carlos Fernandes  Fernando S. Henriques 《Water, air, and soil pollution》1989,48(3-4):409-415

Pyrites extraction at Aljustrel mines, south Portugal, is causing severe metal pollution of soil, water and air, leading to a growing concern with environmental degradation in the mining area and its surroundings. In this work we measured levels of Fe, Mn, Zn, Cu, and Pb in leaves and fruits of holm-oak (Quercus rotundifolia Lam.) trees growing at the outskirts of the mining area. The trees showed pronounced stunting, reduced leaf size and extensive necrotic and chlorotic spotting. The leaves from trees growing in the area under study had much higher concentrations of metals than the controls — ca. 50 times higher for Cu, 20 times for Pb and Zn, 10 times for Fe, and 2 times for Mn — but is is possible that part of the metals associated with the leaves are actually retained in the dense hair cover present on their lower surface. The acorns from the contaminated areas were also metal polluted, particularly with Fe, Zn, and Cu, and this finding raises the threat of animal and human health hazards, since these fruits are commonly used for feeding livestock and are occasionally consumed directly by man.  相似文献   

OCT4 Expression in Outgrowth Colonies Derived from Porcine Inner Cell Masses and Epiblasts     

K Schauser  AT Jensen  M Schmidt  P Hyttel 《Reproduction in domestic animals》2011,46(3):385-392

The present study was conducted to test different methods for porcine inner cell mass (ICM) and epiblast isolation and to evaluate the morphology and expression of pluripotency genes in ICM‐ and epiblast‐derived outgrowth colonies (OCs) and passages thereof with particular attention on the relationship between OCT4 expression and embryonic stem cell (ESC)‐like morphology. A total of 104 zona pellucida‐enclosed and 101 hatched blastocysts were subjected to four different methods of ICM and epiblast isolation, respectively: Manual isolation, immunosurgery, immunosurgery with manual cleaning, or whole blastocyst culture. OCs were established on mouse embryonic fibroblast (MEF) cells and categorized according to morphology and OCT4 staining. Although all isolation methods resulted in ESC‐like OCs, immunosurgery with manual cleaning yielded significantly higher rates of ICM/epiblast attachment and subsequent ESC‐like morphology, whereas no significant difference was found between ICM and epiblasts with respect to these characteristics. All ESC‐like OCs showed nuclear OCT4 staining and expression of OCT4, NANOG and SOX2 as evaluated by RT‐PCR. Upon initial passages, the expression of pluripotency markers was, however, gradually lost in spite of maintained ESC‐like morphology. In conclusion, we have established a robust system for derivation of ESC‐like OCs from porcine ICM and epiblasts and we have shown that localization of OCT4 is associated with an ESC‐like morphology although this relationship is lost during early passages.  相似文献   

Phenology and growth dynamics in Mediterranean evergreen oaks: Effects of environmental conditions and water relations     

C.A. Pinto  M.O. Henriques  J.P. Figueiredo  J.S. David  F.G. Abreu  I. Correia  T.S. David 《Forest Ecology and Management》2011,262(3):500-508

Budburst date and shoot elongation were measured in two mature Mediterranean evergreen oaks (Quercus suber and Quercus ilex) and their relationships with meteorological and tree water status (predawn leaf water potential) data were analysed. Experimental work took place at two sites: Mitra 2 - Southern Portugal (2002-2003) and Lezirias - Central Portugal (2007-2010). Quercus suber phenology was studied at both sites whereas Q. ilex was only studied at Mitra 2. Quercus suber budburst date occurred at a photoperiod around 13.8 h (± 0.26) - late April/early May - and was highly related to the average daily temperature in the period 25 March - budburst date (ca. 1.5 months prior to budburst), irrespective of site location. In that period, budburst date was much more dependent on average maximum than average minimum daily temperature. Base temperature and thermal time for Q. suber were estimated as 6.2 °C (within the reported literature values) and 323 degree-days, respectively. Q. ilex budburst occurred about 6 weeks earlier than in Q. suber (photoperiod: 12.3 h (±0.3)). Relationships of Q. ilex budburst date and temperature were not studied since only 2 years of data were available for this species. Q. suber shoot elongation underlying mechanisms were quite different in the two sites. At Mitra 2 (Q. suber and Q. ilex), there was a considerable tree water stress during the dry season which restricted shoot elongation. Shoot growth was resumed later in the wet autumn when tree water status recovered again. At the Lezirias site Q. suber water status was not restrictive. Therefore, shoot elongation was mainly dependent on nutrient availability in top soil, as suggested by the strong and positive relationships between annual shoot growth and long-term cumulative rainfall (2-4 months) and short-term average temperature (1 month) prior to budburst. Annual shoot elongation at this well-watered site was higher than in Mitra 2, and variability of growth between trees was enhanced after warm, wet springs when shoot elongation was higher. Results obtained are relevant to the carbon balance, productivity and management of evergreen Mediterranean oak woodlands, particularly under the foreseen climate change scenarios.  相似文献   

Growth and fruit production of the tree <Emphasis Type="Italic">Caryocar brasiliense</Emphasis> in the Cerrado of central Brazil     

Rafael Nunes Zardo  Raimundo Paulo Barros Henriques 《Agroforestry Systems》2011,82(1):15-23

Caryocar brasiliense is a native tree found throughout the Cerrado savanna biome in central Brazil, and is exploited by rural population as food and industry. Although the abundance and popularity of this species in Cerrado have been an important component of local extractive economy, several aspects of sustainability as fruit production per tree size and growth rate have received little attention. We monitored, during two growing seasons, the stem growth rates and fruit production of tree in a wild population in Distrito Federal, central Brazil. The results showed a low growth rate of trees. The proportion of adult population fruiting was higher in 2006 than in 2007. For the smallest size (7.3-cm stem diameter) to begin fruiting, the estimated age was between 30 and 51 years old, and for tree with the largest stem diameter in the plot (43-cm diameter) the age was estimated to be between 110 and 153 years old. The whole fruit production by hectare was highly variable between years and was associated with differences in annual precipitation. The total fruit production was 1,004 fruits per ha (72.9 kg ha⁻¹) in 2006, and 299 fruits per ha (21.7 kg ha⁻¹) in 2007. The fruit production per tree was significantly positively correlated between 2006 and 2007 fruit season. Although an estimated fruit yield for whole Cerrado region is more than enough to support the actual demand, the slow growth rates and intensive harvesting indicates that more attention to sustainable management is required to avert demographic collapse of this cornerstone of the Cerrado extractive economy.  相似文献