Immunological and pathological investigations in equine experimental uveitis

Background

The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined and many variations between experimental animal models and spontaneous disease exist.

Objectives

The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings.

Methods

Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation.

Results

CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction.

Conclusions

Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans.

     

Optimal dietary methionine requirement of juvenile Chinese sucker,Myxocyprinus asiaticus

A total of 630 juvenile Chinese sucker, with an average initial weight of 1.72 ± 0.05 g, were fed seven diets for 56 days to study the effect of dietary methionine levels on growth, feed utilization, body composition and haematological parameters on juvenile Chinese sucker. Diet 1 using fish meal as the sole protein source and diets 2–7 using fish meal and fermented soybean meal as intact protein sources supplemented with crystalline amino acids contained six levels of l ‐methionine ranging from 6.4 to 18.9 g kg^?1 of dry diet at a constant dietary cystine level of 3.7 g kg^?1. Each diet was randomly assigned to three aquaria. Results indicated that the highest weight gain, specific growth rate (SGR), feed efficiency ratio, protein efficiency ratio and protein productive value occurred at 13.9 g methionine kg^?1 diet among the methionine supplemented dietary groups, beyond which they showed declining tendency. The whole body and muscle protein contents of juvenile Chinese sucker were positively correlated with dietary methionine level, while muscle lipid content was negatively correlated with it. The total essential amino acids content of muscle was increased significantly with increasing dietary methionine level from 6.4 to 13.9 g kg^?1 (P < 0.05). Apparent digestibility coefficients of dietary protein were significantly affected by dietary treatments. Serum protein, cholesterol and triacylglycerol increased with increasing dietary methionine levels, but showed a relatively lower value for fish fed the 18.9 g methionine kg^?1 diet. Quadratic regression analysis of SGR against dietary methionine level indicated that optimal dietary methionine requirement for juvenile Chinese sucker was 14.1 g kg^?1 of the diet in the presence of 3.7 g kg^?1 cystine (corresponding to 32.0 g kg^?1 of dietary protein on a dry‐weight basis).     

Mitochondrial DNA RFLP in genus Oryza and cultivated rice

Summary Ninety-three accessions representing 23 species from the genus Oryza were surveyed for restriction fragment length polymorphism (RFLP) in mitochondrial (mt) DNA by probing total DNA with 15 known mt sequences cloned in plasmids from higher plants, and five mt genomic cosmid clones from maize. Very low levels of intra-specific and even intra-cytologically-defined nuclear genome mt DNA RFLP were found. High between-genome differentiation appeared, suggesting phylogenetic relationships consistent with data from previous nuclear and chloroplast (cp) DNA studies. Parallel inheritance of cp and mt DNA was found. There was one major exception: the mt DNA of the allotetraploid CD genome is apparently equally related to two putative diploid progenitors, which is suggestive of an interspecific recombination.RRLP in mt DNA was also probed in 82 cultivars, with four plasmid probes. Some bands not seen in the wild species appeared in O. sativa, with intra-specific polymorphism relatively higher than in the wild species. The pattern of variation paralleled that at the cp DNA level between the indica and japonica subspecies.     

Emerging coherence in a population of chemical oscillators

Coherence of interacting oscillating entities has importance in biological, chemical, and physical systems. We report experiments on populations of chemical oscillators and verify a 25-year-old theory of Kuramoto that predicts that global coupling in a set of smooth limit-cycle oscillators with different frequencies produces a phase transition in which some of the elements synchronize. Both the critical point and the predicted dependence of order on coupling are seen in the experiments. We extend the studies both to relaxation and to chaotic oscillators and characterize the quantitative similarities and differences among the types of systems.     

Portal hypertension in a dog due to circumscribed fibrosis of the wall of the extrahepatic portal vein

A two-and-a-half-year-old German shepherd dog with ascites and a high concentration of blood ammonia was investigated. Sonographically, its liver was normal but the portal vein was dilated and the flow of blood within it was slow. A liver biopsy showed that the liver was normal, and did not reveal any possible cause of portal hypertension or ascites. Postmortem, the cranial part of the portal vein was dilated with a cross-striped internal surface, but the caudal part looked normal; there was a stenotic ring between the normal and dilated parts. Histology of the dilated segment revealed marked hypertrophy of both the internal circular and the external longitudinal smooth muscle layers. At the site of the stenosis, the longitudinal muscular layer was replaced by connective tissue. Circumscribed fibrosis in the wall of the portal vein was responsible for the stenosis and the subsequent prehepatic portal hypertension. The cross-striped pattern in the dilated part of the vein was the result of hypertrophy of the inner circular smooth muscle layer.     

Erythroid progenitor cells from pig bone marrow and peripheral blood

With the intention of using the pig as a large animal model in haematopoietic research, a clonal assay in methylcellulose was developed and the optimal conditions for raising erythroid progenitors from adult pig bone marrow (BM) and peripheral blood (PB) have been established. Progenitor cells were stimulated to proliferate and differentiate in vitro by growth factors containing leucocyte condition medium (LCM), and with recombinant human erythropoietin (rhEpo). The number of PB BFU-E (burst forming units - erythroid) directly depended on the concentration of LCM, but BM BFU-E were not dependent on LCM. Both CFU-E (colony forming units - erythroid) and BFU-E were rhEpo dependent. Despite relatively high but expected individual variations, the mean number of colonies, as well as the functional characteristics of progenitor cells investigated, were similar to those of miniature pigs and some other mammals.     

Bioavailable potassium in river-bed sediments and release of interlayer potassium in irrigated arid soils

Abstract. Crop responses to applied potassium fertilizers are erratic in many arid and semi-arid soils. The potassium supplying potential of river-bed sediments and release of interlayer potassium from eleven alkaline soils were measured in two separate experiments. Sediments from the Chenab and Ravi Rivers in Pakistan were exhausted of potassium by successively growing wheat, maize, mungbean, and wheat in them for a total of 200 days, using Hoagland solution to supply optimum amounts of other nutrients. Cumulative plant dry matter yield was significantly greater on the Chenab sediments. The quantities of potassium supplied to plants from the sediments of the two rivers were also significantly different. Interlayer potassium was extracted for 1230 minutes from a Udic Haplustalf (Pindorian series) by twelve different solutions each with the same electrolyte content (100 cmol). The sodium adsorption ratios (SAR) of the solutions were adjusted to 5, 10, 25, and 50, each with Ca: Mg ratios of 25:75, 50: 50 or 75:25, using solutions of sodium, calcium and magnesium chloride. The potassium released from the soil was inversely related to solution SAR. Increasing proportions of magnesium relative to calcium in solution favoured the release of potassium, except in the SAR 50 solution. Significantly different quantities of potassium were extracted by various solutions. Maximum potassium (442 mg/kg) was extracted by SAR 5 solution with a Ca: Mg ratio of 25:75. Interlayer potassium subsequently removed by this solution from 11 alkaline soils ranged from 407 to 499 mg/kg. The potassium released from all but three of the soils was related to their clay content (r= 0.72; n= 8). The release of potassium from the soils followed the Elovich function. The intercept (X₁) and slope (X₂) estimated for the function was related to potassium released (y) by the equation: y=?1.13 + 2.74X₁?0.014X₂ (r= 0.998; n= 8) The results imply that river sediments treated with irrigation water containing magnesium and sodium ions can contribute substantial amounts of available potassium for plant growth.     

Vigour evaluation for genetics and breeding in rose

Breeding of cut and pot rose cultivars for efficient production under low-energy conditions in greenhouses will be facilitated by understanding the inheritance of vigour. To get insight into the genetic variation of vigour-related traits, a diploid rose population was employed for an evaluation study in greenhouses in The Netherlands and Denmark. For all the traits investigated the population showed a continuous quantitative variation as well as a considerable transgression. For most of the traits, the genetic variation found among the tested entries was highly significant and tended to be large in comparison to the effects of genotype by environment interaction. The heritability based on means of the traits was high and ranged from 68 to 92%. Strong simple correlations (r = 0.65 to 0.95) were found among the traits shoot length, leaf area, leaf dry weight, stem dry weight, total dry weight and growth rate. The total dry weight and leaf area are suggested to be good parameters for early selection of rose genotypes with vigorous growth under suboptimal growth conditions.