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861.
862.
863.
K. J. Nytko M. S. Weyland S. Dressel-Böhm S. Scheidegger L. Salvermoser C. Werner S. Stangl A. C. Carpinteiro B. Alkotub G. Multhoff S. Bodis C. Rohrer Bley 《Veterinary and comparative oncology》2023,21(4):605-615
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. 相似文献
864.
865.
Miguel Mellado Lucía M. Treviño María I. Chavez Francisco G. Véliz Ulises Macías-Cruz Leonel Avendaño-Reyes José E. García 《Reproduction in domestic animals》2023,58(1):39-47
The objective of this retrospective study was to assess the effect of receiving a single (n = 50,285) or double (n = 4392) artificial insemination (AI), 12 h apart, within a timed artificial insemination protocol on pregnancy per AI (P/AI) in nulliparous heifers (inseminated with either sex-sorted or conventional semen) and pluriparous Holstein cows in a commercial dairy herd. Also, this study aimed to investigate the relationship between temperature-humidity index (THI) and time of the first AI and fertility. Fertility of cows receiving two AI with normothermia (THI <68) was higher (p < .05) than cows receiving a single AI (42.9% vs. 36.4%). P/AI of cows receiving two AI with severe heat stress (THI >85) was higher (p < .05) than cows receiving a single AI (21.0% vs. 12.6%). Regardless of heat stress conditions, applying the first AI in the morning increased (p < .05) P/AI in cows with double AI than in cows whose first AI occurred in the afternoon (38.4 vs. 33.3%). With moderate heat stress, and sexed-sorted semen, P/AI to timed AI was higher (65.0 vs. 51.9%; p < .05) in heifers receiving double AI than those serviced once. It was concluded that double AI, 12 h apart, enhanced fertility at timed AI than herd mates with a single AI, particularly with heat stress at breeding. 相似文献
866.
Sophie Miyumo Chrilukovian B. Wasike Evans D. Ilatsia Jörn Bennewitz Mizeck G. Chagunda 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2023,140(1):106-120
This study aimed at investigating the influence of genetic and non-genetic factors on immune traits to inform on possibilities of genetic improvement of disease resistance traits in local chicken of Kenya. Immune traits such as natural and specific antibodies are considered suitable indicators of an individual's health status and consequently, used as indicator traits of disease resistance. In this study, natural antibodies binding to Keyhole Limpet Hemocyanin (KLH-NAbs) was used to measure general disease resistance. Specific antibodies binding to Newcastle disease virus (NDV-IgG) post vaccination was used to measure specific disease resistance. Titers of KLH-NAbs isotypes (KLH-IgM, KLH-IgG and KLH-IgA) and NDV-IgG were measured in 1,540 chickens of different ages ranging from 12 to 56 weeks. A general linear model was fitted to determine the effect of sex, generation, population type, phylogenetic cluster, line, genotype and age on the antibody traits. A multivariate animal mixed model was fitted to estimate heritability and genetic correlations among the antibody traits. The model constituted of non-genetic factors found to have a significant influence on the antibody traits as fixed effects, and animal and residual effects as random variables. Overall mean (±SE) concentration levels for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 10.33 ± 0.04, 9.08 ± 0.02, 6.00 ± 0.02 and 10.12 ± 0.03, respectively. Sex, generation and age (linear covariate) significantly (p < 0.05) influenced variation across all the antibody traits. Genotype effects (p < 0.05) were present in all antibody traits, apart from KLH-IgA. Interaction between generation and line was significant (p < 0.05) in KLH-IgM and NDV-IgG while nesting phylogenetic cluster within population significantly (p < 0.05) influenced all antibody traits, apart from KLH-IgA. Heritability estimates for KLH-IgM, KLH-IgG, KLH-IgA and NDV-IgG were 0.28 ± 0.08, 0.14 ± 0.06, 0.07 ± 0.04 and 0.31 ± 0.06, respectively. There were positive genetic correlations (0.40–0.61) among the KLH-NAbs while negative genetic correlations (−0.26 to −0.98) were observed between the KLH-NAbs and NDV-IgG. Results from this study indicate that non-genetic effects due to biological and environmental factors influence natural and specific antibodies and should be accounted for to reduce bias and improve accuracy when evaluating the traits. Subsequently, the moderate heritability estimates in KLH-IgM and NDV-IgG suggest selection possibilities for genetic improvement of general and specific immunity, respectively, and consequently disease resistance. However, the negative correlations between KLH-NAbs and NDV-IgG indicate the need to consider a suitable approach that can optimally combine both traits in a multiple trait selection strategies. 相似文献
867.
Zoledronate is a bisphosphonate frequently used for the treatment of hypercalcaemia of malignancy and tumour-associated bone pain in dogs, however, there is a paucity of information regarding its use in veterinary medicine. The aim of this retrospective study was to report the tolerability of zoledronate in the palliative treatment of cancer-bearing dogs and secondarily to to assess the efficacy of zoledronate for the treatment of hypercalcaemia of malignancy. Thirty-seven dogs (22 with tumour-associated bone pain and 15 with hypercalcaemia of malignancy) that received 114 zoledronate infusions were included. Tolerability was assessed by the absence of post-zoledronate hypocalcaemia or other adverse events as defined by Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events criteria. Efficacy was assessed by comparison of available ionized calcium levels before and after zoledronate administration in hypercalcaemic dogs. In 79% of zoledronate infusions, no adverse events were reported. The majority of adverse events which occurred in the other 21% of infusions could be attributed to concurrent chemotherapy or the underlying neoplastic disease. There was a small but significant increase in creatinine following treatment with zoledronate, however, none of the dogs developed clinically significant renal disease. In eight hypercalcaemic dogs with available ionized calcium following zoledronate administration, ionized calcium decreased rapidly within 7 days following treatment with zoledronate. Zoledronate is well-tolerated with few recorded adverse events, however, monitoring of serum creatinine is advised. Zoledronate seems to be effective in the treatment of hypercalcaemia of malignancy. 相似文献
868.
869.
870.
G. S. Chaturvedi P. K. Aggarwal A. K. Singh M. G. Joshi S. K. Sinha 《Irrigation Science》1981,2(4):225-235
Summary The effect of irrigation on tillering and tiller mortality in varieties of wheat (Triticum aestivum and T. durum), triticale and barley was studied under field conditions. Low temperature in the early stages of growth promoted production of tillers whereas increase in temperature during extension growth phase increased tiller mortality. More than 1000 tillers m–2 were produced with five irrigations but 40% or more died. With limited water availability tiller production was reduced but so was their mortality. Grain yield in wheat and triticale was positively correlated with productive tillers and negatively correlated with the maximum number of tillers produced in wheat and barley grown under limited irrigation conditions. Varieties with a capacity to produce fewer tillers were identified. Some of them proved more stable in yield. No correlation was found between tiller number and grain yield in the frequently irrigated treatment. 相似文献