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A pot incubation experiment under natural conditions was designed to investigate the effects of three biodegradable chelating agents, namely; the [S,S]-isomer of ethylenediamine disuccinate (EDDS), citric acid (CA), and tetrasodium N,N-Bis(carboxymethyl)-L-glutamate acid (GLDA), on two plant species (Brassica juncea and Brassica rapa) in terms of plant foliar growth, dry matter yield, and heavy metal (HM) accumulation. Both plant species exhibited diminished growth and symptoms of phytotoxicity under HM stress. The application of EDDS and CA affected plant foliar growth, biomass production, and led to the development of chlorotic lesions on leaves. EDDS and CA also decreased the shoot length by 38.5% and 45.2% in B. juncea, and 60.1% and 100% in B. rapa, respectively. In contrast, GLDA relieved HM stress by significantly increasing plant growth (P &gt; 0.05) and was shown to be well tolerated (tolerance index [TI]; B. juncea = 99% and B. rapa = 123%). Among both plants, B. juncea displayed the ability to accumulate a wider range of HMs at higher concentrations. Amongst the three chelators, EDDS induced the highest bioconcentration (BCF) of Pb (2.45), Zn (2.68), and Cd (3.36) while CA achieved better results for Ni (4.01) and Cr (1.45). However, the current results showed that even with the application of chelating agents, HMs were predominantly accumulated in roots and translocation factor was generally less then 1. [https://www.selleckchem.com/products/2-6-dihydroxypurine.html buy 2,6-Dihydroxypurine] The findings of this investigation emphasize that chelate-assisted phytoextraction with Brassica spp. is highly limited in multi-metal settings, making it an unsuitable option for severely contaminated sites.The freely dissolved concentration (Cfree) of hydrophobic organic chemicals (HOCs) in pore water is an important parameter in the risk assessment and management of contaminated sediments and soils. It can be determined most conveniently through ex situ passive sampling, i.e., in the laboratory. For this purpose, samples are taken from the field and transported to the laboratory, where they are stored and possibly manipulated by sieving, freezing, drying and/or grinding. Although the objective of ex situ passive sampling often is to determine a Cfree that reflects the metric under in situ conditions, hardly any information is available on possible effects of sample manipulation. Hence, the present study investigated the impact of freezing, freeze-drying, and grinding on Cfree of HOCs in field sediments, as determined with solid phase microextraction (SPME). Freezing increased the Cfree of 3- and 4-ring polycyclic aromatic hydrocarbons (PAHs) with up to a factor of 4, whereas for 5- and 6-ring PAHs hardly any effects were observed. Generally, additional freeze-drying did not further increase Cfree, but subsequently grinding the samples (further) increased Cfree of all PAHs with up to a factor of 4, leading to an overall maximum observed increase in Cfree of a factor of 16. Probably, these effects are caused by a structural change in the sorption matrix, enhancing PAH availability. The results indicate that freezing, freeze-drying, and grinding prior to ex situ Cfree determinations should be avoided, as these treatments may considerably increase the Cfree of HOCs, leading to an overestimation of risks.Copper toxicosis is a major cause of hepatitis in dogs. We have shown that variants in ATP7A and ATP7B modulate hepatic copper levels in Labrador retrievers and Dobermans. However, these variants cannot fully explain the observed variation in hepatic copper levels in these dog breeds. Homozygous deletion of exon 2 of COMMD1 causes copper toxicosis in Bedlington terriers. We investigated the possible involvement of COMMD1 in the multifactorial aetiology of copper toxicosis in Labrador retrievers and Dobermans. Thirty dogs of each breed with known hepatic copper status were selected for DNA sequence analysis of the three exons and flanking intronic regions of COMMD1. The observed variants were tested for association with hepatic copper levels by linear model analysis. Several variants were observed in the DNA sequence of COMMD1 in both Labrador retrievers (nine variants) and Dobermans (11 variants) but none of these was associated with variations of hepatic copper concentrations. We conclude that COMMD1 did not play a major role in the aetiology of copper associated hepatitis in Labrador retrievers and Dobermans.Mammary tumours occur frequently in female dogs, where such tumours exhibit complexity when examined histologically. These tumours are composed not only of proliferative luminal epithelial cells, but also of myoepithelial cells and/or mesenchymal cells with cartilage and osseous tissues in a solitary mass. The origin of this complexed histogenesis remains speculative, but cancer stem cells (CSCs) are likely involved. CSCs possess self-renewing capacity, differentiation potential, high tumourigenicity in immunodeficient mice, and resistance to chemotherapy and radiation. These cells are at the apex of a hierarchy in cancer tissues and are involved in tumour initiation, recurrence, and metastasis. For these reasons, understanding the properties of CSCs is of paramount importance. Analysis of the characteristics of CSCs may contribute to the elucidation of the histogenesis underlying canine mammary tumours, formulation of novel CSC-targeted therapeutic strategies, and development of biomarkers for early diagnostic and prognostic applications. Here, we review research on CSCs in canine mammary tumours, focusing on (1) identification and properties of CSCs; (2) hypotheses regarding hierarchal structures in simple type, complex type and mixed tumours of the canine mammary gland; and (3) current and prospective studies of CSC metabolism.Hypocobalaminaemia is common in dogs and cats with exocrine pancreatic insufficiency and/or chronic enteropathy. While hypocobalaminaemia has been extensively studied, naturally-occurring serum hypercobalaminaemia (i.e. without supplementation) might be an underestimated finding in small animal medicine. Studies in human medicine have associated hypercobalaminaemia with neoplastic, hepatic and renal disease. Medical records of all dogs and cats with serum cobalamin concentration measurements (2007-2019) were retrospectively analysed; any that had received supplemental cobalamin were excluded from the analysis. Of 654 dogs, 3% (n = 21) were hypercobalaminaemic (median serum cobalamin concentration, 1307 ng/L [965 pmol/L]; range, 914-3561 ng/L [675-2628 pmol/L]). Chronic gastrointestinal signs were common in hypercobalaminaemic dogs (48%). Two of the 21 hypercobalaminaemic dogs were diagnosed with hypoadrenocorticism. Of 323 cats, 11% (n = 34) were hypercobalaminaemic (median serum cobalamin concentration, 1713 ng/L [1264 pmol/L]; range, 1370-3107 ng/L [1011-2293 pmol/L]). The following comorbidities were diagnosed in hypercobalaminaemic cats chronic enteropathy, 65% (n = 22); acute or chronic pancreatitis, 24% (n = 8); cholangiohepatopathy, 18% (n = 6); gastric lymphoma, 6% (n = 2); and 3% hyperthyroidism (n = 1). Naturally-occurring increased serum cobalamin concentrations occurred infrequently in cats and even less often in dogs. Since hypercobalaminaemia can occur in dogs and cats with severe inflammatory, immune-mediated, and neoplastic conditions, it should not be ignored.A commercial Aspergillus galactomannan antigen (GMA) enzyme linked immunosorbent assay (ELISA) is used to support a diagnosis of systemic aspergillosis in dogs. In human patients, false positive results have been associated with administration of medications derived from molds. We sought to determine the effect of administration of a commercially available oral probiotic nutraceutical that contained Aspergillus-derived ingredients on serum and urine Aspergillus GMA levels in dogs by conducting a prospective, cross-over study. Galactomannan index (GMI) was measured on the solubilized probiotic nutraceutical and was positive (GMI ≥ 0.5) with a mean of 7.91. Serum and urine galactomannan indices were measured in 10 healthy dogs before (day 0) and after 1 week (day 7) of probiotic nutraceutical administration, then again 2 weeks after the probiotic nutraceutical was discontinued (day 21). Median (range) serum GMI were 0.19 (0.08-0.62), 0.22 (0.07-1.15) and 0.17 (0.14-0.63) at day 0, 7 and 21, respectively. Two of 10 dogs developed positive GMI (≥0.5) results after probiotic nutraceutical administration; however, no significant changes were noted over the study period. Median (range) urine GMI results were 0.06 (0.04-0.22), 0.07 (0.05-0.41) and 0.06 (0.03-0.16) at day 0, 7 and 21, respectively. A trend towards an increase urine GMI was noted between day 0 and 7 (P = 0.18), and decrease was noted between day 7 and 21 (P = 0.09). Administration of probiotics containing Aspergillus-derived ingredients to dogs did not reliably result in elevated Aspergillus GMA levels.Atrial fibrillation (AF) is the most common non-physiological arrhythmia in dogs and humans. Its high prevalence in both species and the impact it has on survival time and quality of life of affected patients, makes it a very relevant topic for medical research. In dogs, the diagnosis of AF is usually fairly straightforward, but optimal management can be complicated. Rate control is the most commonly used strategy; rhythm control can also be considered in very specific cases. Concurrent congestive heart failure is frequently identified, which represents an extra challenge for the clinicians. This article reviews the current recommendations for the diagnosis and management considerations of AF in dogs. Future perspectives, focusing on new drugs that may prevent development of AF based on recent discoveries, will also be discussed.Atrial fibrillation (AF) is the most common non-physiological arrhythmia in dogs and humans. Its high prevalence in both species and the impact it has on survival time and quality of life of affected patients, makes it a very relevant topic of medical research. Significant developments in understanding the mechanisms underlying this arrhythmia in humans has occurred over the last decades and some of this knowledge is being applied to veterinary medicine, despite the many differences between species. This article reviews the current understanding of the pathophysiology of AF. The epidemiology and classification of AF in dogs will also be discussed.Amyloidosis in Siamese/Oriental cats is a lethal condition with variable age of clinical onset. There is no sex predisposition and clinical signs of disease usually become apparent by 1-7 years of age. In the terminal stages, the liver is enlarged and pale, and contains parenchymal hemorrhages. In the present study, pedigree data from 17 cats with clinical signs consistent with amyloidosis underwent genetic analysis. Necropsy and histopathological data were available for 10 of the 17 cats. Necropsy findings included pale, fragile and enlarged livers with capsular ruptures and parenchymal hemorrhages, and sanguineous effusions in the abdominal cavity. Congo red staining with birefringence confirmed systemic amyloidosis mostly involving the liver and thyroid gland. In four of the 10 cases, protein deposits were classified as amyloid A protein (AA-amyloid) by immunostaining. Pedigree data for all 17 affected cats indicated a familial trait. Animal threshold model analysis demonstrated that the heritability for amyloidosis was 0.