Affiner votre recherche
Résultats 1-10 de 144
Acrylamide-induced changes of granulopoiesis in porcine bone marrow
2021
Grzybowska, Dominika | Snarska, Anna
Due to the widely documented and diverse toxic effects of acrylamide, the authors decided to evaluate the impact of high and low doses of this compound on the process of granulopoiesis in porcine bone marrow. The experiment was conducted on 15 Danish Landrace pigs at the age of 8 weeks. The animals were randomly assigned into three equal groups (n = 5). Control animals received empty gelatine capsules as placebo. Animals in the first experimental group (the LD group) received a low dose of acrylamide of 0.5 μg/kg b.w./day, and animals in the second experimental group (the HD group) received a tenfold higher dose of acrylamide of 5 μg/kg b.w./day. Placebo and acrylamide capsules were administered with feed every morning for 28 days. Bone marrow was collected into tubes without an anticoagulant twice – before the first capsule administration (day 0) and on the 28ᵗʰ day of the study. After drying and staining, bone marrow smears were subjected to detailed cytological evaluation under a light microscope. Changes in cell morphology, i.e. degenerative changes in the cellular nuclei, were observed in both experimental groups. Both low and high doses of acrylamide decreased the number of segmented eosinophils, neutrophilic and segmented metamyelocytes, neutrophils, as well as basophils and basophilic metamyelocytes. Acrylamide at doses of 0.5 μg/kg b.w./day and 5 μg/kg b.w./day clearly influences porcine granulopoiesis.
Afficher plus [+] Moins [-]Influence of Beta-Endorphin on Oxygen Activity of Neutrophils and Total Antioxidant Status in Rats after Chronic Administration of Methimazole
2013
Gołyński Marcin | Lutnicki Krzysztof
The aim of the study was to evaluate the effect of β-endorphin on oxygen activity of polimorphonuclear neutrophils and to investigate the total antioxidant status of blood serum in rats subjected to chronic treatment with methimazole. The study was carried out on 15 male Wistar rats weighing 270-290 g, divided into two groups. The animals from experimental group were administered a 0.05% drinking water solution of methimazole. The oxygen activity of peripheral blood neutrophils was examined using a modified RBA test. The extra-receptor effect of β-endorphin on the respiratory burst of neutrophils was evaluated. The incubation of neutrophils in the presence of phorbol myristate acetate (PMA) in the control group caused a nearly threefold increase in the oxygen activity of the cells compared to the control. Slightly higher values were obtained after addition of β-endorphin at the concentration of 10-6. Lower concentrations of this opioid (10-8 and 10-10) also stimulated oxygen activity but at a lower level than PMA. Naloxone did not affect the oxygen activity only when using β-endorphin in the concentration of 10-6. Naloxone and β-endorphin in the concentrations of 10-8 and 10-10 evoked a linear decrease in the oxygen activity of neutrophils, below the values obtained for PMA. The obtained results suggest that methimazole significantly modulates the generation of reactive oxygen species under the influence of β-endorphin, which stimulates the respiratory burst via the receptor pathway and inhibits it via the extra-cellular pathway. Methimazole also stimulates the anti-free radical defence.
Afficher plus [+] Moins [-]The influence of probiotic administration on the phagocytic and oxidative burst activity of neutrophils and monocytes in the peripheral blood of dairy cows during different lactation periods
2024
Brodzki Piotr | Gorzkoś Hubert | Marczuk Jan | Lisiecka Urszula | Junkuszew Andrzej | Krakowski Leszek | Szczubiał Marek | Brodzki Nikodem | Głodkowska Katarzyna
The objective of this bovine peripheral blood study was a comparative assessment of the phagocytic activity of neutrophils and monocytes and of the intracellular killing capacity of neutrophils from cows given no probiotic and from cows which were administered a probiotic consisting of Saccharomyces cerevisiae, Lactobacillus acidophilus, Lactobacillus plantarum and Rhodopseudomonas palustris. These activity types were compared during different lactation periods.
Afficher plus [+] Moins [-]Effects of repeated lipopolysaccharide treatment on growth performance, immune organ index, and blood parameters of Sprague-Dawley rats
2018
Zhong, Youbao | Zhang, Xianlai | Hu, Xiaofen | Li, Yong
The study was designed to investigate the effects of repeated lipopolysaccharide (LPS) treatment on growth performance, lymphoid organ indexes, and blood cells in Sprague-Dawley rats. Forty healthy weaned Sprague-Dawley rats were randomly equally divided into LPS and control groups. Each rat in the LPS group was injected via the caudal vein with LPS (100 μg/kg b.w.) for 10 days, and the control group was treated with an equal volume of normal saline. On the 1ˢᵗ, 4ᵗʰ, 7ᵗʰ, and 10ᵗʰ days, growth performance, lymphoid organ indexes, and blood cells were evaluated in five necropsied rats. When rats were treated 3–10 times with LPS, their body weight and average daily gains increased more slowly than in the control group (P < 0.05). Repeated LPS treatment significantly increased spleen weight and the ratio of spleen to body weight (P < 0.05). White blood cells, neutrophils, and neutrophil percentage increased (P < 0.05) remarkably, but lymphocyte percentage, haemoglobin, and blood platelet counts decreased significantly (P < 0.05). LPS treatment obviously suppresses growth and promotes peripheral immune organ proliferation. It is indicated that host protective mechanism can be activated by multiple small doses of LPS and prevents organs from further damage during stress status.
Afficher plus [+] Moins [-]Evaluation of serum and urine neutrophil gelatinase-associated lipocalin and cystatin C as biomarkers of acute kidney injury in horses
2021
Siwińska, Natalia | Żak, Agnieszka | Pasławska, Urszula
Diagnosis of acute kidney injury (AKI) in horses is difficult at the subclinical stage, due to nonspecific clinical signs. The aim of this study was to evaluate the concentrations of selected serum and urinary biomarkers in healthy horses, horses at risk of AKI, and those with clinical AKI. Thirty healthy horses, 30 horses at risk of AKI and 11 horses with clinical AKI and azotaemia were included in the study. Serum and urinary neutrophil gelatinase-associated lipocalin (NGAL) and cystatin C were measured using commercially available enzyme immunoassay tests. The median and (in parentheses) first and third quartile concentrations of selected biomarkers in healthy horses, horses at risk of AKI and horses with AKI were respectively as follows: serum cystatin C – 0.25 (0.19–0.37), 0.23 (0.15–0.37) and 0.61 (0.37–1.13) mg/L; serum NGAL – 50.5 (38.8–58.8), 51.1 (40.4–66.9) and 98.1 (59.4–128.2) ng/mL; urinary NGAL – 20.7 (17.9–24.5), 32.3 (32.7–55.8) and 36.6 (26.8–89.9) ng/mL; and urinary cystatin C – 0.1 (0.07–0.13), 0.13 (0.1–0.2) and 0.34 (0.22–0.37) mg/L. There were significant differences in the concentration of all biomarkers between the healthy and AKI-affected horses. Horses with AKI all had biomarker concentrations higher than the healthy horses. None of the biomarkers made azotaemia recognisable in all affected horses. The obtained results indicate the need to create a serum and urinary biomarker panel to detect AKI.
Afficher plus [+] Moins [-]Screening of early diagnostic markers of gentamicin-induced acute kidney injury in canines
2019
Zheng, Jia-San | Jing-Nie, | Zhu, Ting-Ting | Ruan, Hong-Ri | Xue, Wei | Rui-Wu,
The value of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (Kim-1), and liver-type fatty acid binding protein (L-FABP) was assessed in early diagnosis of gentamicin-induced acute kidney injury (AKI) in dogs. Subcutaneous gentamicin injection in 16 healthy adult beagles made the AKI model. Blood was sampled every 6 h to detect NGAL, Kim-1, L-FABP, and serum creatinine (SCr) concentrations. Kidney tissue of two dogs was taken before the injection, as soon as SCr was elevated (78 μmol/L), and when it had risen to 1.5 times the baseline, and haematoxylin-eosin staining and transmission electron microscopy (TEM) were used to observe changes. NGAL, Kim-1, and SCr levels were significantly increased (P < 0.05) at 18, 30, and 78 h post injection, but L-FABP concentration was not associated with renal injury. At the earliest SCr elevation stage, findings were mild oedema, degeneration, and vacuolisation in renal tubular epithelial cells in pathology, and mild cytoplasmic and mitochondrial oedema in TEM. At this time point, NGAL and Kim-1 concentrations were significantly increased (P < 0.05), indicating that these two molecules biomark early kidney injury in dogs. Using receiver operating characteristic curve analysis, their warning levels were > 25.31 ng/mL and > 48.52 pg/mL. Plasma NGAL and Kim-1 above warning levels are early indicators of gentamicin-induced AKI in dogs.
Afficher plus [+] Moins [-]Elastase, Myeloperoxidase, and Alkaline Phosphatase Release and Free Radical Generation in Neutrophils Isolated from Blood of Sows at Different Stages of Oestrous Cycle
2013
Wessely-Szponder Joanna | Bobowiec Ryszard
The aim of the study was to assess the influence of the oestrous cycle phase on neutrophil secretory activity and to extrapolate it to susceptibility to uterine infections. The obtained results indicate that the highest enzyme release seen in the late follicular phase (elastase release was 42.18 ±3.11% of maximal release, myeloperoxidase was 45.0 ±5.12%, and alkaline phosphatase was 44.75 ±9.0%) was related to the level of 17β-oestradiol in plasma. Similarly, a free radical generation was also the most enhanced during this phase. Significantly lower values were obtained from sows during the luteal phase in regard to both enzyme release (36.62 ±3.58% for elastase, 27.87 ±8.7% for myeloperoxidase, and 22.12 ±2.4% for alkaline phosphatase), and that of free radicals (2.28 1.6 μM/106 cells for nitric oxide and 2.47 0.6 nM/106 cells for superoxide).
Afficher plus [+] Moins [-]Use of a biopolymer delivery system to investigate the influence of interleukin-4 on recruitment of neutrophils in equids
2020
Godbout, Mireille | Vargas, Amandine | Helie, Pierre | Bullone, Michela | Lavoie, Jean-Pierre
OBJECTIVE To use a biopolymer delivery system to investigate the ability of interleukin (IL)-4 to recruit neutrophils into subcutaneous tissues of equids. ANIMALS 16 horses and 2 ponies. PROCEDURES Animals were assigned to 3 experiments (6/experiment). Effects of recombinant equine (Req) IL-4 (100, 250, or 500 ng/site) versus a positive control (ReqIL-8; 100 ng, 250 ng, or 1 μg/site) and a negative control (Dulbecco PBSS or culture medium) on neutrophil chemotaxis were assessed after SC injection into the neck with an injectable biopolymer used as the vehicle. Tissue samples including the biopolymer plug were collected by biopsy at various time points from 3 hours to 7 days after injection. Neutrophil infiltration was evaluated by histologic scoring (experiments 1, 2, and 3) or flow cytometry (experiment 3). RESULTS Histologic neutrophil infiltration scores did not differ significantly among treatments at most evaluated time points. On flow cytometric analysis, log-transformed neutrophil counts in biopsy specimens were significantly greater for the ReqIL-8 treatment (1 μg/site) than the negative control treatment at 3 but not 6 hours after injection; results did not differ between ReqIL-4 and control treatments at either time point. Negative control treatments induced an inflammatory response in most equids in all experiments. CONCLUSIONS AND CLINICAL RELEVANCE Flow cytometry was a more reliable method to estimate neutrophil migration than histologic score analysis. The ReqIL-4 treatment did not induce a detectable neutrophil response, compared with the negative control treatment in this study. Evidence of inflammation in negative control samples suggested the biopolymer is not a suitable vehicle for use in equids.
Afficher plus [+] Moins [-]Use of standard diagnostic techniques to determine eradication of infection in experimental equine septic arthritis
2019
Koziv, R. V. | Yoshimura, S. | Dickinson, R. | Rybicka, J. M. | Moshynskyy, I. | Ngeleka, M. | Bracamonte, J. L. | Simko, E.
Septic arthritis is an important disease in horses, necessitating aggressive and prolonged therapy. In order to guide therapy, reliable methods of detecting the eradication of infection are needed. Therefore, the objective of this study was to investigate detection of eradication of infection in an experimental model of equine septic arthritis using standard diagnostic techniques. For this purpose, 17 adult horses were assigned to 3 experimental groups. The middle carpal joint of each horse was injected with Escherichia coli (Septic group, n = 8), lipopolysaccharide (LPS) (LPS group, n = 6), or sterile saline (Control group, n = 3) at day 0. Contralateral joints were not injected. Standard therapy was applied to all joints except non-injected joints in the Control group at day 1. Sequential samples of synovial fluid (SF) were collected for bacterial culture using 3 culture media [Columbia blood agar (CBA), brain heart infusion broth (BHI), and Signal blood culture medium] and for cytological evaluation [percentage neutrophils (PN), total nucleated cell count (TNCC), and total protein (TP)]. Escherichia coli-specific polymerase chain reaction (PCR) was carried out to detect E. coli DNA in synovial fluid. Culture and PCR were positive for E. coli in all joints injected with E. coli at day 1 and 1 joint was positive on BHI at day 4. Based on the results of bacterial culture, PCR, and TNCC, the elimination of infection in our experimental model occurred by day 4 post-infection in 6 out of 7 cases. Total protein (TP) and PN remained elevated at clinical threshold used for diagnosis of septic arthritis until day 14. In our experimental model of E. coli-induced arthritis, we conclude that TP and PN may not be good indicators for detecting the eradication of bacterial infection caused by E. coli from infected and subsequently treated joints.
Afficher plus [+] Moins [-]Clinicopathologic, hemodynamic, and echocardiographic effects of short-term oral administration of anti-inflammatory doses of prednisolone to systemically normal cats
2019
Khelik, Imal A. | Berger, Darren J. | Mochel, Jonathan P. | Seo, Yeon-Jung | Palerme, Jean-Sebastein | Ware, Wendy A. | Ward, Jessica L.
OBJECTIVE To evaluate the clinicopathologic, hemodynamic, and echocardiographic effects of short-term administration of anti-inflammatory dosages of prednisolone to systemically normal cats. ANIMALS 10 cats with allergic dermatitis and 10 healthy control cats. PROCEDURES Cats with allergic dermatitis were randomly allocated to 2 groups and received 2 dosages of prednisolone (1 and 2 mg/kg/d, PO, for 7 days) in a crossover design followed by 9-day tapering and 14-day washout periods. Each prednisolone-treated cat was matched to a healthy control cat on the basis of sex, neuter status, age (± 1 year), and body weight (± 10%). Control cats received no treatment during the 35-day observation period. Clinicopathologic, echocardiographic, and hemodynamic variables were measured at baseline (day 0) and predetermined times during and after prednisolone administration and compared within and between the 2 treatment groups. RESULTS Prednisolone-treated cats had expected clinicopathologic alterations (mild increases in neutrophil and monocyte counts and serum concentrations of albumin, cholesterol, and triglycerides) but systolic arterial blood pressure; blood glucose, serum potassium, and cardiac biomarker concentrations; urinary sodium excretion; and echocardiographic variables did not differ significantly from baseline at any time. Statistically significant, albeit clinically irrelevant, increases in blood glucose and N-terminal pro-B-type natriuretic peptide concentrations were observed between baseline and the prednisolone pharmacokinetic steady state (7 days after initiation) only when the 2-mg/kg dosage was administered. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated short-term oral administration of anti-inflammatory dosages of prednisolone did not cause relevant hemodynamic, echocardiographic, or diabetogenic effects in systemically normal cats with allergic dermatitis.
Afficher plus [+] Moins [-]