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Inactivated H5 antigens of H5N8 protect chickens from lethal infections by the highly pathogenic H5N8 and H5N6 avian influenza viruses
2018
Jin, Myongha | Jang, Yunyueng | Seo, Taehyun | Seo, Sang Heui
Introduction: Highly pathogenic Asian H5-subtype avian influenza viruses have been found in poultry and wild birds worldwide since they were first detected in southern China in 1996. Extensive control efforts have not eradicated them. Vaccination prevents such viruses infecting poultry and reduces the number lost to compulsory slaughter. The study showed the efficacy of inactivated H5 vaccine from the H5N8 virus against highly pathogenic H5N8 and H5N6 avian influenza viruses in chickens. Material and Methods: Reverse genetics constructed an H5 vaccine virus using the HA gene of the 2014 H5N8 avian influenza virus and the rest of the genes from A/PR/8/34 (H1N1). The vaccine viruses were grown in fertilised eggs, partially purified through a sucrose gradient, and inactivated with formalin. Chickens were immunised i.m. with 1 µg of oil-adjuvanted inactivated H5 antigens. Results: Single dose H5 vaccine recipients were completely protected from lethal infections by homologous H5N8 avian influenza virus and shed no virus from the respiratory or intestinal tracts but were not protected from lethal infections by heterologous H5N6. When chickens were immunised with two doses and challenged with homologous H5N8 or heterologous H5N6, all survived and shed no virus. Conclusion: Our results indicate that two-dose immunisations of chickens with H5 antigens with oil adjuvant are needed to provide broad protection against different highly pathogenic H5 avian influenza viruses.
显示更多 [+] 显示较少 [-]Screening for circulating miR-208a and -b in different cardiac arrhythmias of dogs
2018
Noszczyk-Nowak, Agnieszka | Zacharski, Maciej | Michałek, Marcin
In recent years, the high sensitivity and specificity of novel miRNA biomarkers have been utilised for early diagnosis and treatment monitoring of various diseases. Previous reports showed that abnormal expression of miR-208 in mice resulted in the development of an aberrant cardiac conduction system and consecutive arrhythmias. On the other hand, a study on infarcted human heart tissue showed upregulation of miR-208a in subjects with ventricular tachyarrhythmias compared to healthy controls. We prospectively investigated the expression of miR-208a and -208b in the serum of dogs presenting different cardiac arrhythmias. A total of 28 dogs with atrial fibrillation (n = 8), ventricular premature contractions (n=6), conduction system disturbances (n = 7), and free of heart conditions (as controls) (n = 7) were enrolled in the study. Total RNA was extracted from serum samples and miR-208a and -b, miR-16 as well as a cel-miR-39-5p spike-in were analysed with qPCR and ddPCR. miR-208a and miR-208b were not expressed in any of the samples. The calculated ddPCR miR-16 relative expression (normalised with cel-miR-39 spike-in) showed a good correlation (r = 0.82; P < 0.001) with the qPCR results. This outcome warrants further investigation, possibly focusing on tissue expression of miR-208 in the canine heart.
显示更多 [+] 显示较少 [-]Toxicological evaluation of flumequine in pubertal male rats after oral administration for six weeks
2018
Kang, JeongWoo | Hossain, Md Akil | Choi, Byungkook | Cho, Joon-Hyoung | Kang, Seok-Jin | Ku, Hyun-Ok | Jeong, Sang-Hee | Kang, Hwan-Goo
Veterinarians use flumequine (FLU) widely but its toxicological effects are still unclear. FLU doses of 53, 200, or 750 mg/kg were administered orally for six weeks to pubertal male rats for evaluation of their toxicity. Weight gain was poorer after seven days of exposure to FLU 750, but relative weights of the brain, adrenal and thyroid glands, and testes were notably higher. Haematological and lipid profile parameters, cardiac markers, and inorganic phosphate significantly increased in the FLU 750 group. Blood glucose, oestradiol and serum concentrations of immunoglobulins G (IgG) and E (IgE) significantly decreased after treatment. The levels of interleukins 10 (IL-10) and 6 (IL-6) fell significantly in the FLU 200 and FLU 750 groups. Cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) and cyclooxygenase-2 (Cox-2) expression amplified after treatment. Serum levels of free triiodothyronine (fT3) and free thyroxine (fT4) reduced in the FLU 200 and FLU 750 groups without changes in total T3 or T4 level. All doses of FLU significantly depressed concentrations of thyroid-stimulating hormone (TSH) and testosterone. Histopathology of thyroid glands from rats treated with FLU 750 showed degeneration and depletion of thyroid follicular epithelial cells. Expression of 8-hydroxydeoxyguanosine (8-OHdG) was increased in a dose-dependent manner in the brain, but decreased in the testes. Expression of CYP1A1 increased in the adrenal and pituitary glands. The results of this study suggest that the toxicity of FLU in rats is an effect of its disruptive influence on the pituitary-thyroid hormonal system and on the dysfunction of the immune system.
显示更多 [+] 显示较少 [-]Analysis of haematological and biochemical blood parameters after electrical cardioversion of atrial fibrillation in dogs
2018
Noszczyk-Nowak, Agnieszka | Michałek, Marcin | Janiszewski, Adrian | Kurosad, Agnieszka | Sławuta, Agnieszka | Cepiel, Alicja | Pasławska, Urszula
Electrical cardioversion is a therapeutic procedure used to convert various types of arrhythmias back to sinus rhythm. It is used to restore the sinus rhythm in dogs with atrial fibrillation. The effect of the electrical energy used during cardioversion on red blood cells (RBC) is not fully understood. Studies on humans reported lysis of RBC following electrical cardioversion. Similar studies have not been carried out on dogs. The aim of the study was to assess the effect of electrical cardioversion on chosen RBC parameters. The study was carried out on 14 large and giant breed dogs weighing from 30 to 84 kg with lone atrial fibrillation (lone AF). Electrical cardioversion was carried out under general anaesthesia by biphasic shock with 70–360 J of energy. Blood was collected at T0 – during atrial fibrillation, prior to cardioversion, and at T1 – 30 min after electrical cardioversion. Complete blood counts as well as total and direct bilirubin concentrations were evaluated. A maximum output of 360 J was used. In all cases, electrical cardioversion was effective, and no significant changes in the number of RBC and RBC indices were noted. Similarly, there were no statistically significant differences in the levels of total and direct bilirubin. Electrical cardioversion in dogs led neither to statistically nor clinically significant RBC lysis.
显示更多 [+] 显示较少 [-]Cloning and expression of NS3 gene of Pakistani isolate type 2 dengue virus
2018
Yasmin, Farkhanda | Yaqub, Tahir | Idrees, Muhammad | Shahzad, Wasim | Hashmi, Abu Saeed | Aqil, Kiran | Mukhtar, Nadia | Zahoor, Muhammad Yasir | Akhtar, Naeem | Umar, Sajid
Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines. Blood samples from dengue fever (DF) patients were collected and subjected to PCR amplification of the NS3 gene of dengue virus serotype-2 (DENV-2). The NS3 gene was amplified using gene specific primers and cloned in the TA cloning vectors. The gene was successfully expressed in mammalian expression vector pcDNA3.1. The current finding was different from a previously reported DENV-2 strain replicon constructed in different cells, in which the whole genetic material of the virus was used instead of an active protease gene, and which gave a low yield of replicon expressing cells. Recombinant NS3 could be used to produce an antibody that is possibly helpful for developing a single step diagnostic assay to detect the dengue virus NS3 antigen in sera of dengue patients.
显示更多 [+] 显示较少 [-]Histamine content in rennet ripening cheeses during storage at different temperatures and times
2018
Madejska, Anna | Michalski, Mirosław | Pawul-Gruba, Marzena | Osek, Jacek
In recent years, there has been a great interest in biogenic amines such histamine, as they are associated with the quality and safety of some kinds of fermented foods. The aim of this study was to evaluate the effect of temperature and storage time on the content of histamine in cheeses. Samples of mould and hard cheeses were examined with RP-HPLC with an organic-aqueous mobile phase containing acidic buffer and chaotropic salt. The samples were stored either at 22 ± 2°C for 42 days (mould and hard cheeses) or at 4 ± 2°C for 112 days (mould cheeses) and 133 days (hard cheeses). The mean total histamine content in cheeses stored at 22°C was higher than the content in those stored at 4°C, with the highest concentrations found in Gorgonzola Piccante cheese (730.47 mg/kg). Histamine concentration in some types of cheeses exceeded the toxic threshold dose, indicating that after long or inadequately cool storage they may not be safe for consumers. To protect cheeses from contamination with histamine-producing bacteria and to safeguard consumers from poisoning, factors conducive to this amine’s formation should be minimised during cheese processing. Suitable temperature and time during storage of cheeses are recommended to avoid the intoxication. Monitoring of this toxin in food is necessary to ensure safety of consumers.
显示更多 [+] 显示较少 [-]Influence of inosine pranobex on cell viability in normal fibroblasts and liver cancer cells
2018
Tobólska, Sylwia | Terpiłowska, Sylwia | Jaroszewski, Jerzy | Siwicki, Andrzej Krzysztof
Inosine pranobex (Isoprinosine) stimulates cell-mediated immune responses to viral infections in humans and might have also therapeutic use in animals. The aim of this study was to compare three in vitro cytotoxicity assays on mouse embryo fibroblasts and liver cancer cells and determine their ability to detect early cytotoxic effects for inosine pranobex. BALB/3T3 clone A31and HepG2 cells were incubated with inosine pranobex at concentrations from 0.1 to 1,000 μg/mL. Cell viability was determined with the MTT reduction, the LHD release, and the NRU tests. A decrease in the cell viability was observed after incubating the BALB/3T3 clone A31and HepG2 cells with inosine pranobex. Based on the cytotoxicity endpoints measured in these investigations in BALB/3T3 clone A31cells, it can be concluded that the cell membrane may be the first part of the cell to be affected by inosine pranobex. The disintegration of lysosomes and mitochondria follows mitochondria damage. In HepG2 cells likewise, the cell membrane may be the first part of the cell to be affected by inosine pranobex. Also in liver cancer cells, the disintegration of mitochondria (assessed with the MTT reduction assay) and next of lysosomes (assessed with the NRU assay) follows mitochondria damage.
显示更多 [+] 显示较少 [-]Cytological evaluation of the influence of high and low doses of bisphenol A on an erythroblastic cell line of porcine bone marrow
2018
Snarska, Anna | Wysocka, Dominika | Rytel, Liliana | Makowska, Krystyna | Gonkowski, Sławomir
Introduction: Bisphenol A (BPA) is a substance widely used in industry for the production of polycarbonates and epoxy resins used in packaging and containers for beverages, contact lenses, compact discs (CDs), window panes, and many other elements. This compound belongs to the group of polyphenols and xenoestrogens commonly found in the human environment. What we know about BPA is still insufficient to enable us to protect our health against its adverse effects, and current knowledge of the influence of BPA on erythroblastic cell lines in bone marrow is rather fragmentary. The aim of the experiment was to assess the effect of two doses of BPA (0.05 mg/kg and 0.5 mg/kg b.w. per day) on myeloid haematopoiesis. Material and Methods: During this experiment, the number of all types of cells in the erythroblastic cell line was evaluated in porcine bone marrow before and after BPA administration. Results: The obtained results clearly indicate changes in haematopoietic activity of the bone marrow, which was demonstrated by a decrease in erythroblastic cell line production in both experimental groups. The haematological effects of the bone marrow changes were anaemia, caused by a number of erythrocytes which was depressed due to their immaturity, and a significant decrease in mean cellular volume in both groups. Conclusion: The harmful effect of high and low doses of BPA on haematopoietic processes was proved.
显示更多 [+] 显示较少 [-]Effects of natural antioxidants on the stability of omega-3 fatty acids in dog food
2018
Glodde, Florentina | Günal, Mevlüt | Kinsel, Mary E. | AbuGhazaleh, Amer
The efficiency of five natural antioxidants (curcumin, cranberry, pomegranate, grape seed extract (GSE), and açai berry) in reducing lipid oxidation in dog food was compared to that of the synthetic antioxidant butylated hydroxyanisole (BHA). In two different experiments content parameters were measured after 12 days of storage at 55°C. In experiment one, the natural antioxidants were added at 0.2% and BHA at 0.02% of the food (DM basis), and samples were analysed for thiobarbituric acid-reactive substances (TBARS). In experiment two, the effects of GSE and curcumin at two admixture proportions (0.1% and 0.2% of food DM) on omega-3 fatty acid (FA) content were evaluated. TBARS values were lower than the control (P < 0.01) for curcumin, cranberry, pomegranate, and GSE but not for the açai berry (P > 0.05). By day 12, although there were no significant differences (P > 0.05) between the two curcumin treatments, they preserved higher concentrations of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (P < 0.05) than the BHA and control treatments. The addition of GSE or BHA to dog food held (P < 0.05) the concentrations of EPA higher than the control. The concentrations of EPA and DHA for the 0.2% GSE treatment were greater (P < 0.05) than the 0.1% GSE treatment. Grape seed extract at 0.2% lost less (P < 0.05) EPA concentration than BHA. The present results showed that, except for açai berry, the tested natural antioxidants could be used as a substitute for BHA in dog food.
显示更多 [+] 显示较少 [-]Ready-to-eat meat products as a source of Listeria monocytogenes
2018
Kurpas, Monika | Wieczorek, Kinga | Osek, Jacek
In 2015 in the European Union member states listeriosis caused 270 deaths. Food is the route of transmission in 99% of all human infection cases. Several studies from different countries have shown that the presence of Listeria monocytogenes in food can be as high as 58.3%. One of the most important ways to protect food from these microorganisms is to prevent the spread of the bacteria at processing plants at different stages of food production chain. The ability of L. monocytogenes to survive in extreme conditions and to form biofilms on various surfaces is a significant challenge for food safety. Removal of these bacteria from niches in processing plants is difficult and requires the use of sanitisers and precise equipment cleaning. The presence of L. monocytogenes in processing environment at slaughterhouses, deli meat factories or in retail may be a reason of cross-contamination. Proper hygienic systems applied by workers in food preparing places and knowledge about different routes of spreading of these bacteria may effectively decrease the risk of food contamination. Standardised legal regulations and control of meat product manufacture should be a fundamental way to protect food from L. monocytogenes contamination.
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