Extracellular heat shock protein 70 levels in tumour-bearing dogs and cats treated with radiation therapy and hyperthermia

Hyperthermia is a form of a cancer treatment which is frequently applied in combination with radiotherapy (RT) to improve therapy responses and radiosensitivity. The mode of action of hyperthermia is multifactorial; the one hand by altering the amount of the blood circulation in the treated tissue, on the other hand by modulating molecular pathways involved in cell survival processes and immunogenic interactions. One of the most dominant proteins induced by hyperthermia is the major stress-inducible heat shock protein 70 (Hsp70). Hsp70 can be found in the blood either as a free-protein (free HSP70) derived from necrotic cells, or lipid-bound (liposomal Hsp70) when it is actively released in extracellular vesicles (EVs) by living cells. The aim of the study was to evaluate the levels of free and liposomal Hsp70 before and after treatment with RT alone or hyperthermia combined with radiotherapy (HTRT) in dogs and cats to evaluate therapy responses. Peripheral blood was collected from feline and canine patients before and at 2, 4, 6 and 24 h after treatment with RT or HTRT. Hsp70 enzyme-linked immunosorbent assays (ELISAs) were performed to determine the free and liposomal Hsp70 concentrations in the serum. The levels were analysed after the first fraction of radiation to study immediate effects and after all applied fractions to study cumulative effects. The levels of free and liposomal Hsp70 levels in the circulation were not affected by the first singular treatment and cumulative effects of RT in cats however, after finalizing all treatment cycles with HTRT free and liposomal Hsp70 levels significantly increased. In dogs, HTRT, but not treatment with RT alone, significantly affected liposomal Hsp70 levels during the first fraction. Free Hsp70 levels were significantly increased after RT, but not HTRT, during the first fraction in dogs. In dogs, on the other hand, RT alone resulted in a significant increase in liposomal Hsp70, but HTRT did not significantly affect the liposomal Hsp70 when cumulative effects were analysed. Free Hsp70 was significantly induced in dogs after both, RT and HTRT when cumulative effects were analysed. RT and HTRT treatments differentially affect the levels of free and liposomal Hsp70 in dogs and cats. Both forms of Hsp70 could potentially be further investigated as potential liquid biopsy markers to study responses to RT and HTRT treatment in companion animals.     

An acute case of Pimelea elongata toxicity in cattle in western New South Wales

In May 2019, 96 cattle died from Pimelea toxicity in a period of 19 days after potential exposure, with the first deaths occurring within 5 days. After examining the circumstances, we suspect that several factors contributed to the deaths. These included that recently purchased stock and transported had access to flooded land containing Pimelea elongata. This weed species contains simplexin and 18 other compounds. Roots, flowers and seeds are significantly more toxic than the stem, branches and leaves. We suspect that thirsty and hungry stock consumed seed and roots from flooded pastures and consumed lethal doses of simplexin. Blood tests were not good indicators of the conditions. Management strategies are suggested.     

Interpretation of solute profile dynamics in irrigated soils

Summary Knowledge of the flux of water flowing through macropores in soils is required to devise management strategies for efficient fertiliser use and to prevent fast movement of solutes and pollutants to groundwaters. Water and solute balances in soil profiles were used to develop a simple model for assessing the magnitude of macropore flow. Fluxes of water bypassing the soil matrix were calculated at 35 sites to be between 0 and 415 mm y^–1, with the flux being < 200 mm y^–1 at most sites. The maximum flux was three times the flux flowing through the soil matrix but only one third of that infiltrating the soil. The flux of macropore flow was not simply related to soil types or soil properties, although the highest fluxes did occur in cracking soils. A qualitative method of using soil chloride profiles to indicate the occurrence (but not magnitude) of bypass flux was also demonstrated. Both these quantitative and qualitative assessments of bypass flow should assist in interpreting root-zone hydrology in soils.     

Determination of soil water content by X-ray computed tomography and magnetic resonance imaging

Summary Experiments were conducted to compare the use of X-ray computed tomography (CT) and magnetic resonance imaging (MRI) methods for determining water content in soil. Soil cores of Mexico silt loam packed at bulk densities of 1.2, 1.3, 1.4, and 1.5 Mg/m³ and Crider silty clay packed at bulk densities of 1.3, 1.4, 1.5, and 1.6 Mg/m³ were evaluated using a CT scanner. Results indicate that the X-ray CT explained 98% of the variation in water content over a range from air-dry to saturation. Three attempts were made to obtain MRI scans of soil cores varying in soil water content. Two of these attempts were made with contrasting agents. No images were obtained of the soil cores during all three attempts. It is suggested that the failure to obtain images of soil cores is closely related to the settings of the pulse repetition time and the spin echo time on the MRI unit. The range in settings for these two parameters on the commercial MRI unit used in this study did not allow short increments to be selected and therefore it was not possible to obtain reconstructed images of the soil cores for this experiment. However accessibility to a prototype MRI unit should allow more conclusive work to determine the full capabilities of MRI for determining soil water content.Contribution from the Missouri Agricultural Experiment Station Journal No. 10424, Department of Agronomy, University of Missouri, Columbia, MO 65211, USA     

Simulation of the intake and partition of nutrients by the dairy cow: Part I — Management control in the dairy enterprise; philosophy and general model construction

The development of management control techniques for the dairy derd is discussed in this paper in relation to the rationale behind the construction of a detailed model of milk production in the individual cow. The movement towards a more flexible and individualised basis for predicting yield, which does not depend on historical records or standard energy systems, is highlighted.The overall concept and approach of the model are set out and the control aspects and structural framework of the program explained. Subsequent papers in the series will deal in more detail with the major sections of the program in order to illustrate how the mechanisms of the model actually operate and to provide results and an account of the validation procedure.