Temporal localization of immunoreactive transforming growth factor beta1 in normal equine skin and in full-thickness dermal wounds

OBJECTIVE: To describe the localization of immunoreactive transforming growth factor (TGF)-beta1 in both normal skin and full-thickness dermal wounds of the limb and the thorax of the horse. STUDY DESIGN: Six full-thickness excisional wounds were created on the lateral aspect of one metacarpal region and on the midthoracic area of each horse. Sequentially collected tissue specimens from wound margins were assessed for TGF-beta1 expression by immunohistochemistry. ANIMALS: Four horses (2 to 4 years of age). METHODS: A neutralizing monoclonal anti-human TGF-beta1 antibody was used to detect the spatial expression of TGF-beta1 protein by immunohistochemical localization in biopsies obtained before wounding and at 12 and 24 hours, and 5, 10, and 14 days. RESULTS: No differences in localization of immunoreactive TGF-beta1 were detected between limb and thorax, for either intact skin or wounds. Unwounded epidermis stained moderately for TGF-beta1 protein throughout all layers, whereas the dermis was relatively devoid of immunoreactivity. During the acute stage of repair, migrating epithelium lost its stain, whereas cells of epidermal appendages remained strongly immunoreactive. The epithelium recovered its TGF-beta1 immunoreactivity during wound remodeling, although cells of the stratum corneum remained negative. Macrophages of the inflammatory exudate had positive cytoplasmic staining that diminished with time. Immunoreactivity of granulation tissue fibroblasts was evident early on and increased throughout the repair process. CONCLUSIONS: TGF-beta1 is constitutively expressed in normal, unwounded equine epithelium. Its expression is upregulated within the skin on injury and is associated with the cells involved in wound repair. CLINICAL RELEVANCE: A more precise understanding of the temporal and spatial expression of TGF-beta1 during wound repair in horses should provide the groundwork for possible future manipulations of both normal and aberrant tissue repair.     

Uncommon associations in target resistance among French populations of Myzus persicae from oilseed rape crops

Within the framework of a molecular exploration of target resistance in populations of Myzus persicae on oilseed rapes in France, (1) the S431F mutation (coding gene ace2), although previously reckoned to be rare, revealed to be frequent, (2) M918L (phenotypically characterised) and L932F (both on para) were found for the first time in M. persicae, and (3) a linkage was revealed between M918L and S431F. While until recently populations developing on French oilseed rapes were dominated by genotypes possessing pyrethroid target resistance and esterase overproduction, to date a different type of dominating genotype, equipped with carbamate and pyrethroid target resistance, seems to be invading such fields.     

Large-scale deployment of a rice 6 K SNP array for genetics and breeding applications

Background

Fixed arrays of single nucleotide polymorphism (SNP) markers have advantages over reduced representation sequencing in their ease of data analysis, consistently higher call rates, and rapid turnaround times. A 6 K SNP array represents a cost-benefit “sweet spot” for routine genetics and breeding applications in rice. Selection of informative SNPs across species and subpopulations during chip design is essential to obtain useful polymorphism rates for target germplasm groups. This paper summarizes results from large-scale deployment of an Illumina 6 K SNP array for rice.

Results

Design of the Illumina Infinium 6 K SNP chip for rice, referred to as the Cornell_6K_Array_Infinium_Rice (C6AIR), includes 4429 SNPs from re-sequencing data and 1571 SNP markers from previous BeadXpress 384-SNP sets, selected based on polymorphism rate and allele frequency within and between target germplasm groups. Of the 6000 attempted bead types, 5274 passed Illumina’s production quality control. The C6AIR was widely deployed at the International Rice Research Institute (IRRI) for genetic diversity analysis, QTL mapping, and tracking introgressions and was intensively used at Cornell University for QTL analysis and developing libraries of interspecific chromosome segment substitution lines (CSSLs) between O. sativa and diverse accessions of O. rufipogon or O. meridionalis. Collectively, the array was used to genotype over 40,000 rice samples. A set of 4606 SNP markers was used to provide high quality data for O. sativa germplasm, while a slightly expanded set of 4940 SNPs was used for O. sativa X O. rufipogon populations. Biparental polymorphism rates were generally between 1900 and 2500 well-distributed SNP markers for indica x japonica or interspecific populations and between 1300 and 1500 markers for crosses within indica, while polymorphism rates were lower for pairwise crosses within U.S. tropical japonica germplasm. Recently, a second-generation array containing ~7000 SNP markers, referred to as the C7AIR, was designed by removing poor-performing SNPs from the C6AIR and adding markers selected to increase the utility of the array for elite tropical japonica material.

Conclusions

The C6AIR has been successfully used to generate rapid and high-quality genotype data for diverse genetics and breeding applications in rice, and provides the basis for an optimized design in the C7AIR.

     

Landscape context and selection for forest edge by breeding Brown-headed Cowbirds

We evaluated support for four alternate hypotheses explaining the distribution of breeding Brown-headed Cowbirds (Molothrus ater) in forests at varying distances from the forest edge in three Midwestern USA landscapes with varying amounts of forest fragmentation (core forest area ranged from 5 to 70%). We focused on breeding cowbirds’ use of forest because of the risk of nest parasitism to forest-dwelling hosts and to identify factors affecting breeding cowbird habitat selection. We compared distances of cowbird locations in the forest from the forest edge (“edge distances”) to distances of random forest locations in the entire landscape or within individual cowbird home ranges. We analyzed 1322 locations of 84 cowbirds across three landscapes. We found support for the landscape context hypothesis that breeding cowbird preference for forest edge varied with landscape context. Ninety percent of cowbird locations were within 150–350 m of forest edge, despite the overall availability of forest at greater distances from edge (as far as 500–1450 m) both within cowbird home ranges and the entire forested landscape. Cowbird preference for edge varied by landscape context largely due to differences in the availability of forest edge. In a highly fragmented forest cowbirds utilized the entire forest and likely viewed it as “all edge.” In less fragmented forests, cowbirds preferred edge. We consider how variation in cowbird edge preference might relate to patterns in host abundance, host diversity, and host quality because cowbird movements indicate they are capable of using forest farther from edges.     

Comparison of field- and laboratory-developed estuarine benthic communities for toxicant-exposure studies

The structures of macrobenthic communities that colonized sand-filled boxes in laboratory and field were compared to learn if laboratory-developed assemblages of animals used in toxicity studies realistically simulate those in nature. Laboratory boxes were colonized for eight weeks in the Spring and Fall by planktonic larvae from continuously-supplied unfiltered seawater; field boxes, by naturally-occurring estuarine animals. Laboratory communities had larger numbers, but fewer species than field communities. One-fourth of the species found in field boxes also occured in laboratory boxes. Species density, diversity, and dominance were similar in both environments in the Fall, but differed in the Spring. The degree of similarity of laboratory assemblages of benthic animals to the highly variable assemblages in the field indicates applicability of laboratory toxicity studies to nature.     

Effects of past and current crop management on soil microbial biomass and activity

Because soil biota is influenced by a number of factors, including land use and management techniques, changing management practices could have significant effects on the soil microbial properties and processes. An experiment was conducted to investigate differences in soil microbiological properties caused by long- and short-term management practices. Intact monolith lysimeters (0.2 m² surface area) were taken from two sites of the same soil type that had been under long-term organic or conventional crop management and were then subjected to the same 2.5-year crop rotation [winter barley (Hordeum vulgare L.), maize (Zea mais L.), lupin (Lupinus angustifolius L.), and rape (Brassica napus L. ssp. oleifera)] and two fertilizer regimes (following common organic and conventional practices). Soil samples were taken after crop harvest and analyzed for microbial biomass C and N, microbial activity (fluorescein diacetate hydrolysis, arginine deaminase activity, and dehydrogenase activity), and total C and N. The incorporation of the green manure stimulated growth and activity of the microbial communities in soils of both management histories. Soil microbial properties did not show any differences between organically and conventionally fertilized soils, indicating that crop rotation and plant type had a larger influence on the microbial biomass and enzyme activities than fertilization. Initial differences in microbial biomass declined, while the effects of farm management history were still evident in enzyme activities and total C and N. Links between enzyme activities and microbial biomass C varied depending on treatment, indicating differences in microbial community composition.     

Influence of saponin plants on the volatile fraction of thyme in herbal teas

Combinations of thyme, cowslip and liquorice roots are often used in the treatment of upper respiratory tract infections. Therefore the volatile fraction of herbal teas prepared from thyme (Thymus vulgaris) and the effect of combining with cowslip (Primula veris/P. elatior) and liquorice roots (Glycyrrhiza glabra) on the volatiles were analyzed. Volatile compounds were isolated by hydrodistillation and solid phase extraction and analyzed by GC-MS. Thymol was also quantified by HPLC. The total amount of volatiles as well the thymol content was decreased with increasing proportions of cowslip or liquorice in the infusion extracts whereas the proportion of monoterpene hydrocarbons increased.     

Free galactose concentrations in fresh and stored apples (Malus domestica) and processed apple products

Gas chromatography was used to quantitate free galactose in Braeburn, Fuji, Red Delicious, and Spartan apples during cold storage, after thermal processing of apple slices and in juice produced using clarification and/or liquifaction enzymes. Spartan had significantly higher galactose levels as compared to Red Delicious apples, but changes in galactose in all varieties during 9 months of cold storage were insignificant. Blanching and canning decreased galactose levels, but doubling the thermal processing during canning increased the free galactose concentration detected in plant tissue. An enzymatic liquefaction aid used to prepare apple juice dramatically increased the free galactose content while a clarification aid caused only a slight increase due to its selective action on soluble pectin. These findings provide useful information for dietitians to base diet recommendations for galactosemic patients.     

Ordering of quantum dots using genetically engineered viruses

A liquid crystal system was used for the fabrication of a highly ordered composite material from genetically engineered M13 bacteriophage and zinc sulfide (ZnS) nanocrystals. The bacteriophage, which formed the basis of the self-ordering system, were selected to have a specific recognition moiety for ZnS crystal surfaces. The bacteriophage were coupled with ZnS solution precursors and spontaneously evolved a self-supporting hybrid film material that was ordered at the nanoscale and at the micrometer scale into approximately 72-micrometer domains, which were continuous over a centimeter length scale. In addition, suspensions were prepared in which the lyotropic liquid crystalline phase behavior of the hybrid material was controlled by solvent concentration and by the use of a magnetic field.