Serum concentrations of methimazole in cats after a single oral dose of controlled-release carbimazole or sugar-coated methimazole (thiamazole)

In the past 5 years, the incidence of canine skin infections caused by resistant strains of Staphylococcus (pseud)intermedius has increased. Many older antibiotics are used to treat these infections because the sensitivity can be demonstrated in vitro. Additionally, many of these older drugs are efficacious and unlikely to induce multidrug resistance. More than a decade ago, the antibiotic tylosin tartrate was reported to be efficacious in vitro and in vivo against Staphylococcus intermedius. The purpose of this study was to determine whether S. (pseud)intermedius isolated from untreated pyoderma cases at veterinary referral centers across the United States are sensitive in vitro to this antibiotic. Minimum inhibitory concentrations for tylosin tartrate and other commonly used antibiotics were determined for 103 isolates. Most (82.61%) of the isolates not exposed to antibiotics in the 3 months before submission were sensitive to tylosin tartrate. These findings suggest that tylosin tartrate warrants further study as a first-line option for the treatment of dogs initially presenting with pyoderma.     

Methionine oxidation enhances κ-casein amyloid fibril formation

The effects of protein oxidation, for example of methionine residues, are linked to many diseases, including those of protein misfolding, such as Alzheimer's disease. Protein misfolding diseases are characterized by the accumulation of insoluble proteinaceous aggregates comprised mainly of amyloid fibrils. Amyloid-containing bodies known as corpora amylacea (CA) are also found in mammary secretory tissue, where their presence slows milk flow. The major milk protein κ-casein readily forms amyloid fibrils under physiological conditions. Milk exists in an extracellular oxidizing environment. Accordingly, the two methionine residues in κ-casein (Met(95) and Met(106)) were selectively oxidized and the effects on the fibril-forming propensity, cellular toxicity, chaperone ability, and structure of κ-casein were determined. Oxidation resulted in an increase in the rate of fibril formation and a greater level of cellular toxicity. β-Casein, which inhibits κ-casein fibril formation in vitro, was less effective at suppressing fibril formation of oxidized κ-casein. The ability of κ-casein to prevent the amorphous aggregation of target proteins was slightly enhanced upon methionine oxidation, which may arise from the protein's greater exposed surface hydrophobicity. No significant changes to κ-casein's intrinsically disordered structure occurred upon oxidation. The enhanced rate of fibril formation of oxidized κ-casein, coupled with the reduced chaperone ability of β-casein to prevent this aggregation, may affect casein-casein interaction within the casein micelle and thereby promote κ-casein aggregation and contribute to the formation of CA.     

New insights into an ancient antibrowning agent: formation of sulfophenolics in sodium hydrogen sulfite-treated potato extracts

The effect of sodium hydrogen sulfite (S), used as antibrowning agent, on the phenolic profile of potato extracts was investigated. This extract was compared to one obtained in the presence of ascorbic acid (A). In the presence of A, two major compounds were obtained, 5-O-caffeoylquinic acid (5-CQA) and 4-O-caffeoyl quinic acid. With S, their 2'-sulfo-adducts were found instead, the structures of which were confirmed by nuclear magnetic resonance spectroscopy and mass spectrometry. Also, for minor caffeoyl derivatives and quercetin glycosides, the corresponding sulfo-adducts were observed. Feruloyl and sinapoyl derivatives were not chemically affected by the presence of S. Polyphenol oxidase (PPO) was thought to be responsible for the formation of the sulfo-adducts. This was confirmed by preparing 2'-sulfo-5-O-caffeoyl quinic acid in a model system using 5-CQA, sodium hydrogen sulfite, and PPO. This sulfo-adduct exhibited a small bathochromic shift (λmax 329 nm) as compared to 5-CQA (λmax 325 nm) and a strong hypochromic shift with an extinction coefficient of 9357±395 M(-1) cm(-1) as compared to 18494±196 M(-1) cm(-1), respectively. The results suggest that whenever S is used as an antibrowning agent, the O-quinone formed with PPO reacts with S to produce sulfo-O-diphenol, which does not participate in browning reactions.     

Nitrogen fertilization does not affect micronutrient uptake in grain maize (Zea mays L.)

Abstract

Due to continuous single nitrogen fertilization, we hypothesized a built-up deficiency of micronutrients in crops that would limit plant growth and crop quality. In 2-year field experiments using urea-N fertilized grain maize (Zea mays L.), hybrid KWS 2376 at 0, 120 and 240 kg N ha^?1 crop uptake of Zn, Mn, Cu and Fe was studied at DC 32, DC 61 and in the grain harvested. Micronutrient contents at DC 32 stage – 1st node (aboveground phytomass) and DC 61 – flowering (ear leaf) were all at levels indicative of adequate micronutrient supply to the crop. At both sampling occasions the Fe:Zn and Fe:Mn ratios were adequate implying that Fe did not inhibit the uptake of Zn and Mn. The application of nitrogen increased the Fe content at the 1st sampling in both years; in the second year the same was also the case for the Zn content. Nitrogen nutrition increased the contents of Mn and Fe at the 2nd sampling only in year 2; in the other treatments no changes were observed in the micronutrient contents. Micronutrient correlations in the grain were discovered between Zn and Mn contents and between Fe and Mn contents. In the second year the highest N-rate significantly increased the Fe and Zn content of the grain compared with the lower rates of nitrogen fertilization. Grain yields were not affected by the rate of nitrogen and ranged between 13.65 and 14.34 t ha^?1 (1st year) and between 13.68 and 14.18 t ha^?1 (2nd year). Nitrogen fertilization did not reduce the content of micronutrients in the plant or grain of maize. It is evident that the continuous single use of N fertilization so far has not resulted in a micronutrient deficiency of the plants limiting the nutrient density of the grain or reducing its quality.     

Effects of seedbed properties on crop emergence: 3. Effects of firming of seedbeds with various sowing depths and water contents

Abstract

Extensive experiments were carried out in shallow plastic boxes placed directly on the ground in the field to study the effects of seedbed properties on the emergence of various crops in a cool temperate climate. In a group of experiments with barley (Hordeum vulgare L.), we studied the effects on crop emergence of firming (slight compaction) of the seedbed, simulating the recompacting effects of rolling after sowing or press wheels on the seed coulters. Most of the experiments were carried out without irrigation after sowing. The firming usually had a slightly positive effect on emergence when the water content in the surface layer at sowing was below the wilting point. When the water content in the surface layer was higher, firming often reduced emergence drastically, particularly with deep sowing and in coarse-textured soils. The main reason for negative effects was harmful hardening of the surface layer when the more firm seedbed gradually dried out. When irrigation kept the seedbed continuously moist, the negative effect of firming was almost eliminated. Very high initial water content in the basal layer tended to delay surface layer drying and hardening, and to reduce the negative effect of firming. Firming only slightly influenced the evaporative water losses from the soil. In contrast to the results presented here, previous field trials with cereals have usually resulted in more positive effects of rolling after sowing. This indicates that other effects than firming, such as modification of sowing depth and reshaping of the soil surface, are other important effects of rolling.     

Collection and morphological characterization of Panicum coloratum L. in Argentina

Panicum coloratum (Poaceae) is a perennial grass native to South Africa, distributed all over the world, but poorly adopted by ranchers in Argentina. Adapted to a wide range of soil and climatic conditions, it constitutes a good forage resource for zones with edaphic and climatic restrictions, where cattle rising activities are here displaced. The high polymorphism in the species has made it difficult to delineate sub specific taxonomic categories. It has been classified in botanical varieties, types and/or cultivars. In order to document the morphological variability in P. coloratum and to investigate the differences between var. makarikariense and var. coloratum, a collection was gathered in INTA Rafaela composed by fourteen accessions from different provinces of Argentina: six accessions of var. makarikariense and eight from var. coloratum. The evaluation of 152 individuals gives evidence of a wide morphological variation in the collection in traits related to forage and caryopses production; seven out of nine traits showed significant differences between var. makarikariense and var. coloratum. Based on the study of local type specimens, a morphological key to distinguish between P. coloratum varieties is provided. These results report new information about the diversity in P. coloratum in Argentina and provide valuable insights for future use of the collection as the base material of a breeding program.     

Fusarium head blight progression and yield response of bread wheat as affected by fungicides and spray regimes under field condition in southern Ethiopia

Journal of Crop Science and Biotechnology - Fusarium head blight (FHB) is one of the destructive diseases in wheat-producing areas of the world. Field experiments were conducted during the 2019...