Chondroitin sulfate extracted from ascidian tunic inhibits phorbol ester-induced expression of Inflammatory factors VCAM-1 and COX-2 by blocking NF-kappaB activation in mouse skin

Inflammatory factors are known to play a key role in promoting tumorigenesis; therefore, it is a promising strategy to inhibit the inflammation for cancer prevention. The current study was performed to investigate the potential effects of chondroitin sulfate (CS) extracted from ascidian tunic on the expression of inflammatory factors induced by treatment with 12- O-tetradecanoylphorbol-13-acetate (TPA) and to elucidate the underlying molecular mechanism of CS action in mouse skin inflammation. TPA was topically applied to the shaven backs of ICR mice with or without CS (1 or 2 mg) for 4 h. The results demonstrated that CS suppressed TPA-induced edema and reduced the expression of cyclooxygenase-2, vascular cell adhesion molecule-1, and Akt signaling in mouse skin. These studies suggest that CS from ascidian tunic may be developed as an effective natural anti-inflammatory agent.     

Production of fertile hybrid germplasm with diploid Australian Gossypium species for cotton improvement

The 17 wild Australian Gossypium species are distant diploid relatives of the commercial tetraploid cottons, G. barbadense L. and G. hirsutum L. They interest cotton breeders as a source of terpenoid-aldehyde-free seeds, a trait only found in five Australian Gossypium species. They elicit further interest because some species grow near current and projected cotton growing areas in Australia and thus could serve as unintentional recipients of transgenes from genetically engineered cotton cultivars. The utility of the wild Australian Gossypium species in cotton breeding depends on the ability to generate fertile hybrids, and to the extent this is possible under glasshouse conditions, it allows predictions regarding the probability that fertile hybrids between the transgenic cottons and spatially associated populations of wild species will arise without human manipulation. The Australian Gossypium species fall into three morphologically and cytologically distinct groups designated the C, G, and K genomes, The G-genome species hybridize most readily with G. arboretum (a diploid A-genome cultivated cotton), while the C- and K-genome species are more compatible with G. hirsutum (a tetraploid AD-genome cultivated cotton). These intergenomic hybrids are sterile, and the chromosome complement of the hybrids must be doubled prior to backcrossing to G. hirsutum. The only exceptions were four G. hirsutum × K-genome triploids, which exhibited limited female fertility when backcrossed to G. hirsutum. Two of the three diploid species geographically associated with commercial cotton fields (G. australe F. Mueller & G. rotundifolium Fryxell, Craven & Stewart) failed to produce hybrid progeny when pollinated with G. hirsutum pollen; the third species (G. sturtianum J.H. Willis) produced only 5 sterile triploids from 25 pollinations. Thus, the probability that wild species could serve as recipients of transgenes is functionally zero, especially in conjunction with the profound prezygotic barriers that separate the cultivated tetraploid cottons from their wild Australian relatives. Eighteen new fertile synthetic polyploids and 23 self-fertile derivatives of two synthetic hexaploids were produced. Synthetic tetraploids require greater effort to backcross than do synthetic hexaploids. These fertile hybrids represent a new avenue of introgression of genes from wild Australian Gossypium species into commercial cotton cultivars, an avenue limited only by the level of recombination. This revised version was published online in July 2006 with corrections to the Cover Date.     

Bud activity of decapitated, nursery-grown plants ofTriplochiton scleroxylon in Nigeria: effects of light, temperature and humidity

This study is a continuation of earlier work on apical dominance inTriplochiton scleroxylon K. Schum., aimed at the development of an early clonal selection test for branching habit and yield in tree improvement programmes. Decapitated plants of five to seven clones were treated with either: (i) two photon flux densities (photosynthetically active radiation at full or 10% sunlight, approximately 2000 and 200 μmol quanta m⁻²s⁻¹ measured at midday on a clear day); (ii) two temperatures (ambient 30°C or 40°C in a polythene tent); (iii) two humidities (ambient=40–70% relative humidity at 30°C or with humidification=95–100% relative humidity at 28°C). Bud activity, shoot length and numbers of leaves produced following decapitation were all increased by high photon flux density and high humidity. In contrast to similar studies under glasshouse conditions in Britain, dominance was not re-established following the initial period of sprouting. The sprouting phase was similar in Nigeria and Britain. Clonal differences in bud activity were similar under different treatments, although there were minor changes in ranking. Increasing the air temperatures from 30 to 40°C resulted in leaf areas of 165 cm² and 23 cm², respectively. Normal polarity of lateral shoot production following decapitation was completely inverted by high temperature.     

The relationship of resting S-T segment depression to the severity of subvalvular aortic stenosis and the presence of ventricular premature complexes in the dog

Electrocardiograms (ECG) from 35 dogs with subvalvular aortic stenosis (SAS) with a left ventricular outflow tract pressure gradient (PG) of > or =50 mm Hg were retrospectively evaluated for S-T segment depression (STD, > or =0.2 mV in lead II). Pressure gradient, age, heart rate (HR), and number of ventricular premature complexes (VPCs) on a 24-hour ambulatory ECG for dogs with STD were not significantly different from those for dogs without STD. The S-T segment deviation did not correlate significantly with PG, age, HR, or VPCs. The significance of STD in the dog with SAS remains uncertain. Long-term prospective studies are needed to fully understand this observation.     

Evaluation of intraruminal devices for combined facial eczema control and trace element supplementation in sheep

Intraruminal devices containing zinc oxide are very effective in preventing facial eczema in sheep. In the present study such devices augmented with various amounts of selenium and cobalt have been evaluated for their ability to improve the Se and CO status of pregnant ewes, as reflected by changes in blood Se and serum Vitamin B12 concentrations. Devices containing 16.4 mg of Se (as sodium selenate) and 20.4 mg of Co (as cobalt sulphate) were effective in increasing and maintaining elevated blood Se concentrations for at least 84 days and serum Vitamin B12 for 42 days. Such devices will therefore prevent trace element deficiencies in sheep as well as providing protection against facial eczema.     

The efficacy of selenium dioxide as a selenium supplement for dairy cattle

The efficacy of selenium dioxide (SeO2) was similar to sodium selenate (Na2SeO4 x 10H2O), in terms of increasing and maintaining blood Se concentrations, when administered orally twice daily to give 0.64 mg of Se/day to grazing dairy cows for 55 days.     

A study of dendritic cell and MHC class II expression in dogs with immunomodulatory-responsive lymphocytic-plasmacytic pododermatitis

The term immunomodulatory-responsive lymphocytic-plasmacytic pododermatitis (ImR-LPP) has previously been proposed to denote a sub-population of dogs with idiopathic pododermatitis. The objective of this study was to investigate dendritic cell (DC) and MHC class II antigen expression in lesional skin of dogs with ImR-LPP (n = 47). Median epidermal CD1c⁺ cell counts were 37.8 and 12.5 mm⁻¹ in ImR-LPP dogs and healthy controls (n = 27), respectively (P < 0.01), while the corresponding dermal cell counts were 180.9 and 45.0 mm⁻², respectively (P < 0.01).Intra-epidermal clusters of DCs were observed in 18/47 dogs with ImR-LPP. Median epidermal MHC class II⁺ cell counts were 32.5 and 10.5 mm⁻¹ in ImR-LPP dogs and healthy controls, respectively (P < 0.01), while the corresponding dermal cell counts were 216.9 and 46.9 mm⁻², respectively (P < 0.01). Dermal MHC class II⁺ staining was primarily associated with DCs (47/47 dogs), mononuclear inflammatory cells (45/47), fibroblast-like cells (19/47) and vascular endothelium (14/47). The DC hyperplasia and increased MHC class II expression in lesional ImR-LPP skin are consistent with enhanced antigen presentation, and suggest that both parameters may contribute to the pathogenesis of ImR-LPP through the priming and activation of CD4⁺ T cells. Equally, it is possible that the enhanced DC numbers observed in this study may contribute to the immunoregulation of steady-state pathology in lesional ImR-LPP skin through additional expanded, although as yet unresolved, mechanisms.     

Training farmers in rational drug-use improves their management of cattle trypanosomosis: a cluster-randomised trial in south Mali

We carried out a stratified, cluster-randomised, controlled trial in south Mali in 2004 to evaluate the impact of providing information on the diagnosis and treatment of bovine trypanosomosis by farmers. We recruited cattle farmers (444) in 46 villages and used stratified, restricted-randomisation to assign villages to either the test or control group. Farmers in the test group received an information leaflet designed to address gaps in farmer knowledge likely to lead to inadequate treatment; their knowledge was assessed before the intervention, and at 2 weeks and 5 months after the intervention. We assessed the quality of farmer treatments by measuring clinical outcomes in cattle 2 weeks after selection and treatment. As an indicator of herd health, we assessed the mean hematocrit of the village herd before, and 5 months after, the intervention. To account for clustering, we analysed data using generalised estimating equations. Improvements in farmer knowledge of trypanosomosis diagnosis and treatment at 2 weeks and 5 months in the group receiving information were 23% and 14% greater at 2 weeks and 5 months, respectively. In the test group, 84% of farmer treatments were successful, compared to 73% in the control group. Giving rational drug-use information to farmers improved their knowledge and management of trypanosomosis as well as clinical outcomes in cattle they treated and had no discernible negative impacts.