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Apoptosis in natural rabies virus infection in dogs
2016
Vural, Sevil Atalay | Bozkurt, Mehmet Fatih | Ozkara, Ali | Alcigir, Mehmet Eray | Ilhan, Fatma Sayin
Introduction: In the present study apoptosis was investigated in the cornu ammonis and cerebellum of 10 dogs naturally infected with rabies virus. Diagnosis of rabies was based on the results of fluorescent antibody staining and experimental inoculation.Material and Methods: The paraffin tissue sections were stained with haematoxylin and eosin, avidin-biotin complex peroxidase (ABC-P), and terminal deoxynucleotidyl transferase biotin-dUTP nick end-labelling (TUNEL) methods.Results: Histopathological examination revealed encephalomyelitis of varying severity and the presence of Negri bodies. Dense rabies antigens were determined in the motor neurons with ABC-P method. On the other hand, Bcl-2 protein and Bax protein gave positive reaction in seven and five cases, respectively. TUNEL staining demonstrated very marked apoptotic changes in the nuclei of neurons localised deep in the substantia alba of the cerebellum. Similar changes were also determined in perivascular mononuclear cells and glia cells within the substantia alba. No apoptopic changes were found in the motor neurons of the cornu ammonis.Conclusion: The absence of apoptotic changes in the neurons was considered to be the consequence of the necrotic changes that developed in these neurons.
Afficher plus [+] Moins [-]First report of Leptospira infections in red deer, roe deer, and fallow deer in Poland
2016
Żmudzki, Jacek | Jabłoński, Artur | Arent, Zbigniew | Zębek, Sylwia | Nowak, Agnieszka | Stolarek, Agnieszka | Parzeniecka-Jaworska, Marta
Introduction: Recently in Europe an increase in the population of red deer (Cervus elaphus), roe deer (Capreolus capreolus), and fallow deer (Dama dama) has been observed. Research on the prevalence of Leptospira infections in Polish cervids has been performed for the first time.Material and Methods: During 2014/2015 hunting season, 147 blood samples from red deer, roe deer, and fallow deer were collected. The animals originated from different geographical regions across Poland. Serum samples were tested by microscopic agglutination test (MAT) for the presence of specific antibodies to the following Leptospira serovars: Icterohaemorrhagiae, Grippotyphosa, Sejroe, Tarassovi, Pomona, Canicola, Bratislava, Hardjo, Ballum, Zanoni, Hebdomadis, and Poi.Results: Serum antibody titres specific to Grippotyphosa, Pomona, and Zanoni serovars were found; none of the sera were positive for any of the other serovars. Out of 147 serum samples only 7 were positive, which gave an overall prevalence of 4.8% in the tested animal population.Conclusion: The low Leptospira antibody titres along with the low number of positive serum samples in deer indicate that these animals may not act as significant reservoirs of Leptospira for either humans or animals in Poland.
Afficher plus [+] Moins [-]Mastitis associated with Prototheca zopfii - an emerging health and economic problem on dairy farms
2016
Milanov, Dubravka | Petrović, Tamaš | Polaček, Vladimir | Suvajdžić, Ljiljana | Bojkovski, Jovan
Increased incidence of protothecal mastitis has been recorded in several countries in the past ten years. The main goal of this article is to draw the attention of scientific and professional community to the emerging issue of mammary protothecosis. The article collates currently known facts about infection reservoirs, predisposing factors for the development of mastitis, clinical manifestations of the disease, and potential transmission routes within the herd as well as the measures for control and eradication. We would like to point out that identification of protothecal mastitis on a dairy farm is associated with a range of problems. Early detection of infected animals can be difficult because of predominantly subclinical course of early-stage infection, which easily spreads between cows via the milking system. Spontaneous recovery has not been recorded and infected cows typically develop chronic mastitis with granulomatous infiltration and progressive loss of functional parenchyma of the mammary gland. Substantial economic losses and health damages associated with mammary protothecosis strongly emphasise the need for developing effective prevention strategies aimed at control of the infection.
Afficher plus [+] Moins [-]Influence of post-mortem muscle glycogen content on the quality of beef during aging
2016
Onopiuk, Anna | Półtorak, Andrzej | Wierzbicka, Agnieszka
Introduction: Glycolic changes which occur post-mortem have an impact on the physical and sensory features of beef, which in turn determine the successive processes and influence such beef quality traits as colour, tenderness, and cooling loss. The aim of this study was evaluation of the post-mortem changes in bovine meat during aging, quantitative analysis of glycogen and lactic acid, as well as examination of their impact on technological and sensory quality of selected muscles from Holstein-Friesian × Limousin breed carcasses.Material and Methods: The study included three muscles of different metabolic qualities and sarcomere length: m. semitendinosus, m. longissimus dorsi, and m. psoas major, collected from nine bull carcasses aged 24 ±2 months.Results: Significant correlations were found between the volume of cooling loss on individual days of aging and the pH value of muscle tissue, lactic acid and glycogen content, as well as beef lightness. However, no significant dependency between the volume of glycogen and the intensity of red and yellow colours was detected.Conclusion: The colorimetric analysis of glycogen and lactic acid can be an effective tool in predicting the quality of beef.
Afficher plus [+] Moins [-]Molecular characterisation of Leptospira strains in Pakistan
2016
Sohail, Muhammad Luqman | Khan, Muhammad Sarwar | Avais, Muhammad | Zahoor, Muhammad Yasir | Khattak, Irfan | Ashraf, Aqeela | Naseer, Omer
Introduction: Leptospirosis affects a wide range of mammals, humans, and even a few poikilothermic animal species. In Pakistan, serological studies of equine leptospirosis have reported a prevalence of over 40%, but no study has ever been conducted towards molecular detection of Leptospira in horses. Material and Methods: Blood samples from 128 horses were screened using ELISA and 41 positive samples were examined for the presence of leptospiral DNA using specific primers for 16S rRNA gene. Results: Out of 41 tested samples, 20 samples were found to be PCR-positive, revealing a fragment of 306 bp after gel electrophoresis. Sequencing and phylogenetic analysis of positive samples revealed circulation of pathogenic Leptospira spp. in Pakistani horses. No evidence of circulation of intermediate species was found in this study. Conclusion: This study reports the first molecular evidence of equine leptospirosis in Pakistan and lays ground for further research in this area. It also confirms the efficiency of 16S rRNA for the diagnosis of equine leptospirosis.
Afficher plus [+] Moins [-]Differential toxicities of albendazole and its two main metabolites to Balb/c 3T3, HepG2, and FaO lines and rat hepatocytes
2016
Radko, Lidia | Minta, Maria | Stypuła-Trębas, Sylwia
Introduction: The cytotoxicity of anthelmintic agent, albendazole (ABZ) and its two major metabolites, sulfoxide (ABZSO) and sulfone (ABZ-SO₂), on non-hepatic Balb/c 3T3 line, two hepatoma cell lines (FaO, HepG2), and isolated rat hepatocytes was investigated. Material and Methods: Cell cultures were exposed for 24, 48, and 72 h to eight concentrations of the compounds ranging from 0.05 to 100 μg/mL (ABZ) and from 0.78 to 100 μg/mL (ABZ-SO and ABZ-SO₂). Three different assays were applied in which various biochemical endpoints were assessed: lysosomal activity - neutral red uptake (NRU) assay, proliferation - total protein contents (TPC) assay and lactate dehydrogenase (LDH) leakage assay. Results: The most toxic was albendazole whose EC₅₀ values calculated from the concentration effect curves ranged from 0.2 to 0.5 μg/mL (Balb/c 3T3) and from 0.4 to 73.3 μg/mL (HepG2). Rat hepatoma line and isolated rat hepatocytes were less sensitive to the impact of ABZ. Toxic action expressed as EC₅₀ was recorded after 72 h exposure only in LDH release assay at 0.8 μg/mL and 9.7 μg/mL respectively. The toxicity of metabolites was much lower. The most sensitive to ABZ-SO were fibroblasts and EC₅₀₋₇₂ₕ values were similar in all three assays used, i.e. NRU (14.1 μg/mL), TPC (15.8 μg/mL), and LDH (20.9 μg/mL). In the case of ABZ-SO₂ the mean effective concentrations were the highest, and could be reached only in one LDH assay. These values (μg/mL) were as follows: 65.3 (FaO), 65.4 (HepG2), 75.8 (hepatocytes), and 77.4 (Balb/c 3T3). Conclusion: The differences in in vitro toxicity of albendazole depend on metabolic ability of the cellular models. Primary cultured rat hepatocytes represent a valuable tool to study the impact of biotransformation on the cytotoxicity of drugs.
Afficher plus [+] Moins [-]Isolation and characterisation of peroxiredoxin 6 promoter from sheep (Ovis aries)
2016
Liu, Nan-Nan | Liu, Zeng-Shan | Lu, Shi-Ying | Hu, Pan | Zhang, Ying | Fu, Bao-Quan | Li, Yan-Song | Zhou, Yu | Zhang, Yu | Ren, Hong-Lin
Introduction: Peroxiredoxin 6 (Prdx6) is a bifunctional protein and a unique 1-Cys Prdx of the peroxiredoxin family. The expression and regulation of Prdx6 are implicated in numerous physiological and pathological processes.Material and Methods: Eight stepwise truncated DNA fragments obtained from the 5′-flank region of the Prdx6 gene were prepared and subcloned into the pSEAP2-Enhancer vectors. To investigate the transcriptional activity of the truncated DNA fragments, the recombinant plasmids were transfected into the COS-1 cells and the transcriptional activity was measured via assaying the expression of the reporter gene of the secreted alkaline phosphatase.Results: A 3.4 kb 5′-upstream flank region of the Prdx6 gene was cloned and sequenced. The region from −108 nt to −36 nt of the 5′-flanking region of the Prdx6 gene contained basal transcriptional activity.Conclusion: This result provides the basis for further studies on the gene regulation of the Prdx6-mediated biological processes and on screening for the transacting factors that interact with cis-acting elements of the Prdx6 gene promoter.
Afficher plus [+] Moins [-]Assessment of stallion semen morphology using two different staining methods, microscopic techniques, and sample sizes
2016
Łącka, Katarzyna | Kondracki, Stanisław | Iwanina, Maria | Wysokińska, Anna
Introduction: The aim of this study was to propose the optimal methodology for stallion semen morphology analysis while taking into consideration the staining method, the microscopic techniques, and the workload generated by a number of samples. Material and Methods: Ejaculates from eight pure-bred Arabian horses were tested microscopically for the incidence of morphological defects in the spermatozoa. Two different staining methods (eosin-nigrosin and eosin-gentian dye), two different techniques of microscopic analysis (1000× and 400× magnifications), and two sample sizes (200 and 500 spermatozoa) were used. Results: Well-formed spermatozoa and those with major and minor defects according to Blom’s classification were identified. The applied staining methods gave similar results and could be used in stallion sperm morphology analysis. However, the eosin-nigrosin method was more recommendable, because it allowed to limit the number of visible artefacts without hindering the identification of protoplasm drops and enables the differentiation of living and dead spermatozoa. Conclusion: The applied microscopic techniques proved to be equally efficacious. Therefore, it is practically possible to opt for the simpler and faster 400x technique of analysing sperm morphology to examine stallion semen. We also found that the number of spermatozoa clearly affects the results of sperm morphology evaluation. Reducing the number of spermatozoa from 500 to 200 causes a decrease in the percentage of spermatozoa identified as normal and an increase in the percentage of spermatozoa determined as morphologically defective.
Afficher plus [+] Moins [-]Fluorescein as a diagnostic marker of bladder ruptures: an experimental study on rabbit model
2016
Aksoy, Özgür | Kurt, Başak | Ermutlu, Celal Şahin | Çeçen, Kürşat | Yayla, Sadık | Ekinci, Metin | Özaydin, İsa | Ünlüer, Süleyman Erdinç
Introduction: The aim of this study was to investigate fluorescein use in the diagnosis of bladder ruptures in rabbits as an experimental model.Material and Methods: The study was conducted on male New Zealand rabbits divided into a retrograde fluorescein group (n = 8) and an intravenous (IV) fluorescein group (n = 8). Following general anaesthesia, 10 mL of 10% fluorescein dye (sodium fluoresceine powder) was administered via ureterorenoscope to the bladder of the first group, and 0.5 mL of 10% fluorescein was administered intravenously to the second group. Then, the bladder was viewed through the cystoscope by urethral aspect. After experimental bladder perforation, groups were comparatively evaluated by paracentesis and laparotomy.Results: Following IV injection of fluorescein dye, the bladder veins were stained green within 10 s and then fluorescein mixed with urine flowed into bladder lumen. The green fluid flow was observed in the abdominal cavity after the perforation of the bladder in both groups.Conclusion: Fluorescein can be used as a marker in diagnosis of bladder ruptures. If there is no bleeding or intestinal content in the abdominal cavity, although a smoky yellow-green image is observed, bladder rupture can be suspected.
Afficher plus [+] Moins [-]Pharmacokinetic - pharmacodynamic model and ampicillin residue depletion after intramammary administration in cows
2016
Burmańczuk, Artur | Roliński, Zbigniew | Kowalski, Cezary | Zań, Rafał
Introduction: The objective of this study was to describe a pharmacokinetic–pharmacodynamic (PK/PD) approach for determination of a rational dosage of ampicillin (AMP) and depletion of the antibiotic residues in milk after intramammary administration to cows.Material and Methods: The cows came from different farms from the Lublin Province area. They (n = 9) received 5 g of the drug, containing 75 mg of AMP sodium in physiological solution, through a syringe tube by intramammary administration. Following single intramammary administration, the milk samples (5 mL) were collected after 2, 4, 6, 8, 10, 24, 36, 48, and 60 h. The liquid chromatography-mass spectrometry analysis was performed on the Agilent 1200 system connected to an AB Sciex API 4000™ mass spectrometer. The pharmacokinetic analysis of the concentrations of the antibiotic in milk was performed using software Phoenix® WinNonlin® 6.4. Calculations were made in non-compartmental (slopes, highest, amounts, and moments) and compartmental analysis.Results: The pharmacokinetic characteristics of AMP after intramammary administration indicate rapid elimination of the drug from milk. The mean residence time had a several-fold lower value than the designated elimination half-life and amounts to only 3.4 h. The concentration of the drug in the milk dropped relatively quickly and the process was very dynamic.Conclusion: The conducted research confirms the rationale of using the PK/PD model in order to verify the dosing regimen for other antibiotic groups and various indicators of the applied PK/PD model.
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