Sequestration of N-acetyl-beta-D-glucosaminidase in somatic cells during experimental bovine mastitis induced by endotoxin, Staphylococcus aureus or Streptococcus agalactiae

Experimental mastitis was induced in cows by intramammary infusion of endotoxin, Staphylococcus aureus or Streptococcus agalactiae. The inflammatory response was monitored by somatic cell counting and N-acetyl-beta-D-glucosaminidase (NAGase). NAGase activity was analysed in fresh milk samples in parallel with samples treated by a cycle of freezing and thawing combined with detergent treatment to release the cell-bound NAGase. Before the udder reacted by inflammation, the total NAGase activity consisted of free extracellular activity. Later on when the inflammation was established, much of the milk NAGase remained sequestered intracellularly. S agalactiae was linked with a high degree of cellular NAGase sequestration indicating a blockage of the lysosomal release function from the phagocytes. S aureus delayed the inflammatory response.     

Somatic embryogenesis from floral tissue of cassava (Manihot esculenta Crantz)

The aim of this study was to examine the embryogenic potential of floral material of the cassava cultivar MCOL 1505. Macerated immature inflorescences were found to be highly embryogenic, with almost 78% of the explants producing somatic embryos. Somatic embryos were also produced from whole male florets and half florets although at much lower rates. No regeneration was obtained from anther, microspore or floret wall tissue. Somatic embryos derived from immature inflorescences were regenerated via organogenesis and the plants derived from this process were assessed in terms of phenotype and ploidy level. If haploid plants could be produced by this method, this would have significant implications in assisting traditional cassava breeding, as this would allow homozygosity to be reached more rapidly. In a crop such as cassava, which is highly heterozygous in nature, the use of haploids in a breeding programme could considerably shorten the time taken to produce new desirable cultivars. This is the first report on plant regeneration through somatic embryogenesis from floral tissue of cassava. This revised version was published online in July 2006 with corrections to the Cover Date.     

Antioxidative properties of the essential oil from Pinus mugo

The essential oil from Pinus mugo (PMEO) was tested on its antioxidative capacity. For this purpose, several biochemical test systems were chosen (e.g., the Fenton System, the xanthine oxidase assay, or the copper-induced oxidation of low-density lipoprotein (LDL)). The results show that there is moderate or weak antioxidative activity when tested in aqueous environments, like in the Fenton system, xanthine oxidase induced superoxide radical formation, or in the HOCl driven fragmentation of 1-aminocyclopropane-1-carboxylic acid (ACC). In contrast, when tested in more lipophilic environments (e.g., the ACC-cleavage by activated neutrophils in whole blood) the PMEO exhibits good antioxidative activity. PMEO does also show good antioxidative capacity in another lipophilic test system (i.e., the copper induced oxidation of LDL). Some components of PMEO (i.e., Delta(3)-carene, camphene, alpha-pinene, (+)-limonene and terpinolene) were also tested. As the PMEO, they showed weak or no antioxidant activity in aqueous environments, but some of them were effective antioxidants regarding ACC-cleavage by activated neutrophils in whole blood or copper-induced LDL-oxidation. Terpinolene, a minor component of PMEO, exhibited remarkable protection against LDL-oxidation.     

Vertical profiles reveal impact of ozone and temperature on carbon assimilation of Betula pendula and Populus tremula

Rising temperature and tropospheric ozone (O(3)) concentrations are likely to affect carbon assimilation processes and thus the carbon sink strength of trees. In this study, we investigated the joint action of elevated ozone and temperature on silver birch (Betula pendula) and European aspen (Populus tremula) saplings in field conditions by combining free-air ozone exposure (1.2?×?ambient) and infrared heaters (ambient +1.2 °C). At leaf level measurements, elevated ozone decreased leaf net photosynthesis (P(n)), while the response to elevated temperature was dependent on leaf position within the foliage. This indicates that leaf position has to be taken into account when leaf level data are collected and applied. The ozone effect on P(n) was partly compensated for at elevated temperature, showing an interactive effect of the treatments. In addition, the ratio of photosynthesis to stomatal conductance (P(n)/g(s) ratio) was decreased by ozone, which suggests decreasing water use efficiency. At the plant level, the increasing leaf area at elevated temperature resulted in a considerable increase in photosynthesis and growth in both species.     

Population differentiation and genetic variation inform translocation decisions for Liatris scariosa var. novae-angliae, a rare New England grassland perennial

Augmentation of small rare species populations is sometimes suggested on genetic grounds. However, outbreeding depression via dilution of local adaptation or break-up of genomic coadaptation may occur. These effects depend on the causes of population divergence. Here, we compare genetic measures of population divergence in Liatris scariosa var. novae-angliae, a rare New England perennial. We measured G_ST, neutral marker subdivision, and Q_ST, quantitative subdivision of propagule and juvenile plant traits. G_ST was relatively high. Q_ST for leaf shape exceeded G_ST, indicating local adaptation, while Q_ST for other traits fell within or below the G_ST range. Local adaptation appears low for juvenile traits, although the high G_ST cautions against translocation because of potential coadaptation. If translocation is still required, however, donor populations should contain high quantitative genetic diversity. We assess population size and allozyme diversity as predictors of quantitative genetic variation, but find these poor proxies for direct measurement.     

Genetic regulation of conidiation in Trichoderma hamatun

Achieving a balance between vegetative growth and spore production is essential for successful biocontrol by fungi. Low sporulation rates in the field can result in poor establishment and survival,whereas failure of conidia to recognise hosts can lead to persistence without efficacy. Commercial biocontrol products involve bulk preparations of conidia, however considerable variability in conidiation rates exists between biocontrol agents, which can restrict choice of strain for production. The majority of studies on Trichoderma conidiation have focused on the species T. viride and T. atroviride.These species form conidia in response to blue and near-UV light and/or nutrient deprivation and conidiation proceeds in a highly co-ordinated fashion, however relatively little is known on the genetic basis of Trichoderrma conidiation. In addition, whilst photoconidiation appears to be a general response detailed studies in other Trichoderma species are absent. In this study, conidiation in the lesser known biocontrol species T. hamatum is being investigated using a combined morphological and molecular approach. In contrast to T. atroviride, conidiation in response to blue-light was weaker and variable and suggested that additional triggers may be required for the T. hamatum photoresponse. A series of comparative photoconidiation assays are currently being undertaken investigating the effect of inoculum type and abiotic factors on timing and intensity of the response.Results will be discussed in relation to the current knowledge on conidial morphogenesis in Trichoderma. In addition to these morphological assays, a selection of genes implicated in sporulation and the blue-light responses are currently being isolated and characterised from T. hamatum. Two genes, phr1 and cmp1 , which were isolated previously from T. atroviride will be used as early and late markers of gene expression during the photoresponse in T. hamatum in order to define time points for harvesting comparable stage-specific RNA from T. hamatum and T. atroviride. Using degenerate PCR putative sporulation gene orthologues have also been identified in T. hamatum.Work is currently underway to isolate genomic clones of these genes from T. hamatum and T.atroviride. Sequence and expression analysis of orthologues, including expression in response to abiotic factors will be presented and discussed in relation to the current knowledge of the molecular basis of conidiation in Trichoderma and other filamentous fungi.……     

Multi-time scale analysis of sugarcane within-field variability: improved crop diagnosis using satellite time series?

Within-field spatial variability is related to multiple factors that can be time-independent or time-dependent. In this study, our working hypothesis is that a multi-time scale analysis of the dynamics of spatial patterns can help establish a diagnosis of crop condition. To test this hypothesis, we analyzed the within-field variability of a sugarcane crop at seasonal and annual time scales, and tried to link this variability to environmental (climate, topography, and soil depth) and cropping (harvest date) factors. The analysis was based on a sugarcane field vegetation index (NDVI) time series of fifteen SPOT images acquired in the French West Indies (Guadeloupe) in 2002 and 2003, and on an original classification method that enabled us to focus on crop spatial variability independently of crop growth stages. We showed that at the seasonal scale, the within-field growth pattern depended on the phenological stage of the crop and on cropping operations. At the annual scale, NDVI maps revealed a stable pattern for the two consecutive years at peak vegetation, despite very different rainfall amounts, but with inverse NDVI values. This inversion is linked with the topography and consequently to the plant water status. We conclude that (1) it is necessary to know the crop growing cycle to correctly interpret the spatial pattern, (2) single-date images may be insufficient for the diagnosis of crop condition or for prediction, and (3) the pattern of vigour occurrence within fields can help diagnose growth anomalies.

LC-MS/MS quantification of sulforaphane and indole-3-carbinol metabolites in human plasma and urine after dietary intake of selenium-fortified broccoli

This study aimed at developing a sensitive LC-MS/MS method for the quantification of sulforaphane (SFN) and indole-3-carbinol metabolites in plasma and urine after dietary intake of regular and selenium-fertilized broccoli using stable isotope dilution analysis. In a three-armed, placebo-controlled, randomized human intervention study with 76 healthy volunteers, 200 g of regular (485 μg of total glucosinolates and <0.01 μg of selenium per gram fresh weight) or selenium-fertilized broccoli (589 μg of total glucosinolates and 0.25 μg of selenium per gram fresh weight) was administered daily for 4 weeks. Glucoraphanin and glucobrassicin metabolites quantified in plasma and urine were SFN-glutathione, SFN-cysteine, SFN-cysteinylglycine, SFN-acetylcysteine, and indole-3-carboxaldehyde, indole-3-carboxylic acid, and ascorbigen, respectively. Dietary intake of selenium-fertilized broccoli increased serum selenium concentration analyzed by means of atomic absorption spectroscopy by up to 25% (p < 0.001), but affected neither glucosinolate concentrations in broccoli nor their metabolite concentrations in plasma and urine compared to regular broccoli.     

Ultrasound findings in horses with severe eyelid swelling, and recognition of acute dacryoadenitis: 10 cases (2004-2010)

Objective To report the sonographic findings, treatment, and outcome of horses with severe eyelid swelling, to describe the sonographic appearance of enlarged lacrimal glands, and to describe the clinical features of acute dacryoadenitis. Materials and methods Medical records of all horses with severe eyelid swelling that underwent an ultrasound evaluation of the globe and periorbital structures from 2004–2010 were examined. Cases were limited to those in which the eyelid swelling was so severe that the globe could not be visualized. Results Ten horses met the criteria for inclusion in the study. All cases were unilateral and acute. Marked enlargement of the lacrimal gland was found in five cases, and supported the diagnosis of acute dacryoadenitis. Eyelid abscessation was found in three horses, accompanied by mild to moderate lacrimal gland enlargement in two of the three. Enlarged lacrimal glands were slightly heterogeneous in appearance and could be differentiated from an abscess by imaging the protrusion of the gland from beneath the supraorbital rim. Only two cases of severe eyelid swelling were soley traumatic. Conclusions Severe eyelid swelling was often associated with dacryoadenitis and/or eyelid abscessation. The detection of marked lacrimal gland enlargement in horses with an acute onset of severe painful eyelid swelling is consistent with a diagnosis of acute dacryoadenitis. Ultrasonographic evaluation of eyelid swelling of any degree is warranted to determine if enlargement of the lacrimal gland, etiology notwithstanding, is an underlying or contributing cause.