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Comparative study of leptospiral strains ictero No. 1 and RGA by restriction endonuclease DNA analysis.
1988
Hata K. | Yamaguchi T. | Ono E. | Yanagawa R.
Characteristics and application of monoclonal antibody to progesterone, 2; Development of progesterone enzyme-linked immunosorbent assay (ELISA).
1991
Kang C.B. | Kim J.S.
Histamine and other biogenic amines in food
2020
Durak-Dados, Agata | Michalski, Mirosław | Osek, Jacek
The aim of this paper is to give an overview of the presence of biogenic amines, particularly histamine, in various food products, discuss the most important factors influencing their accumulation, and address potential toxicity and safe limits in food. Biogenic amines are natural components of animal and plant raw materials, where they are present at concentrations appearing non-harmful to human health. Their increased content in foods results from the activity of endogenous enzymes or from the microbial decarboxylation of amino acids during controlled or spontaneous fermentation, processing, storage, and distribution. General knowledge of biogenic amines, factors favouring their formation and their safe limits in food are useful in preventing exposure to their toxic effects on the human body. Based on this information, appropriate prophylaxis can be applied, which will consist primarily of maintenance of good hygiene standards of raw materials and products, employment of appropriate processing procedures and upkeep of sanitary food storage conditions.
显示更多 [+] 显示较少 [-]Cytotoxicity of iron (III), molybdenum (III), and their mixtures in BALB/3T3 and HepG2 cells
2018
Terpiłowska, Sylwia | Siwicka-Gieroba, Dorota | Siwicki, Andrzej Krzysztof
Introduction: Iron and molybdenum are essential trace elements for cell metabolism. They are involved in maintaining proper functions of enzymes, cell proliferation, and metabolism of DNA. Material and Methods: BALB/3T3 and HepG2 cells were incubated with iron chloride or molybdenum trioxide at concentrations from 100 to 1,400 µM. The cells were also incubated in mixtures of iron chloride at 200 μM plus molybdenum trioxide at 1,000 μM or iron chloride at 1,000 μM plus molybdenum trioxide at 200 μM. Cell viability was determined with MTT reduction, LHD release, and NRU tests. Results: A decrease in cell viability was observed after incubating both cell lines with iron chloride or molybdenum trioxide. In cells incubated with mixtures of these trace elements, a decrease in cell viability was observed, assessed by all the used assays. Conclusions: Iron (III) and molybdenum (III) decrease cell viability in normal and cancer cells. A synergistic effect of the mixture of these elements was observed.
显示更多 [+] 显示较少 [-]Phenotypic diversity and potential virulence factors of the Shewanella putrefaciens group isolated from freshwater fish
2019
Paździor, Ewa | Pękala-Safińska, Agnieszka | Wasyl, Dariusz
The Shewanella putrefaciens group are ubiquitous microorganisms recently isolated from different freshwater fish species and causing serious health disorders. The purpose of the study was to characterise isolates of the S. putrefaciens group with special emphasis on elucidating serological diversity and determining putative virulence factors. Isolates collected from freshwater fish (n = 44) and reference strains were used. The identification of bacteria was carried out using biochemical kits and 16S rRNA sequencing. Polyclonal antibodies were prepared against the S. putrefaciens group. The bacterium’s susceptibility to antimicrobial agents, its enzymatic properties, and its adhesion ability to fish cell lines were also tested. Finally, selected isolates were used in challenge experiments in common carp and rainbow trout. Excluding six isolates undeterminable for species, the bacteria were classified to three species: S. putrefaciens, S. xiamenensis, and S. oneidensis, and showed some phenotypic diversity. Fourteen serological variants of the S. putrefaciens group were determined with the newly developed serotyping scheme. Serodiversity may play an important role in the virulence of particular isolates. Further, S. putrefaciens group members adhere to epithelial cells and produce enzymes which may contribute to their virulence. Challenge tests confirmed the pathogenicity of the S. putrefaciens group for fish.
显示更多 [+] 显示较少 [-]Coronaviruses in avian species – review with focus on epidemiology and diagnosis in wild birds
2018
Miłek, Justyna | Blicharz-Domańska, Katarzyna
Coronaviruses (CoVs) are a large group of enveloped viruses with a single-strand RNA genome, which continuously circulate in mammals and birds and pose a threat to livestock, companion animals, and humans. CoVs harboured by avian species are classified to the genera gamma- and deltacoronaviruses. Within the gamma-CoVs the main representative is avian coronavirus, a taxonomic name which includes the highly contagious infectious bronchitis viruses (IBVs) in chickens and similar viruses infecting other domestic birds such as turkeys, guinea fowls, or quails. Additionally, IBVs have been detected in healthy wild birds, demonstrating that they may act as the vector between domestic and free-living birds. Moreover, CoVs other than IBVs, are identified in wild birds, which suggests that wild birds play a key role in the epidemiology of other gammaCoVs and deltaCoVs. Development of molecular techniques has significantly improved knowledge of the prevalence of CoVs in avian species. The methods adopted in monitoring studies of CoVs in different avian species are mainly based on detection of conservative regions within the viral replicase, nucleocapsid genes, and 3’UTR or 5’UTR. The purpose of this review is to summarise recent discoveries in the areas of epidemiology and diagnosis of CoVs in avian species and to understand the role of wild birds in the virus distribution.
显示更多 [+] 显示较少 [-]Beef tenderness improvement by dietary vitamin D3 supplementation in the last stage of fattening of cattle
2017
Półtorak, Andrzej | Moczkowska, Małgorzata | Wyrwisz, Jarosław | Wierzbicka, Agnieszka
Tenderness is the most important characteristic of meat, determining consumer approval. There are numerous methods of its improvement, although of diverse effectiveness. addition of vitamin D₃ to the feed for a short period before slaughter (7–10 days) is one of the natural ways to enhance the tenderness. Vitamin D₃ is responsible for Ca²⁺ mobilisation in serum and increase in activity of proteolytic enzymes belonging to calpains, which results in significant improvement of beef tenderness and reduction of ageing time. The use of vitamin D₃ is an application tool determining tenderness improvement of beef with substantial reduction in processing costs. Moreover, shorter post mortem ageing process will exceed the retail display time, which will consequently reduce losses due to unsold meat being returned from shops to the manufacturers. Based on the results of studies conducted over the last 15 years, this paper presents the possibility and the effects of the use of vitamin D₃ to improve beef tenderness.
显示更多 [+] 显示较少 [-]Weaning induces changes in behavior and stress indicators in young New Zealand rabbits
2018
Heba S. A. Gharib | Azhar F. Abdel-Fattah | Haiam A. Mohammed | Doaa M. Abdel-Fattah
Objective: The present study was carried out to investigate the influence of weaning on the abnormal behavior, behavioral problems and some stress indicators in young rabbits. Materials and methods: The study was conducted on seventy two New Zealand rabbit kits which were divided into two groups, one reared with their dams (Unweaned rabbits) and the other group reared without their dams (Weaned rabbits). Rabbits are reared on traditional wire net batteries. A scan sample technique was used during the observation period of the recorded traits. Rabbits behavior was observed three times per day at (from 8.00 to 9.00 h.), (from 12.00 to 13.00 h) and (from 15.00 : 16.00 h) for three days weekly to each group during the experimental period (6 weeks). The observed activities were recorded at 10 min interval for rabbits in each subgroup (6 subgroups for each group). Two blood samplings were taken after weaning process for monitoring some stress indicators.Results: The results showed that the bare biting and lixite bite were significantly affected by weaning which were increased in the weaned group than the unweaned group. Other abnormal behavioral traits and behavioral problems were not influenced by weaning process. The results found that cortisol, growth hormone levels, superoxide dismutase and catalase enzyme activities were significantly increased in serum after weaning.Conclusion: The weaning process has negative effect on some behavioral and physiological responses. So, rearing the young rabbits with their mothers is advantageous from the viewpoint of animal welfare. The findings of this study may help to find out suitable strategies to minimize post weaning stress in both human beings and domestic animals. [J Adv Vet Anim Res 2018; 5(2.000): 166-172]
显示更多 [+] 显示较少 [-]Inhibition of cytochrome P450 enzymes involved in ketamine metabolism by use of liver microsomes and specific cytochrome P450 enzymes from horses, dogs, and humans
2011
Mossner, Lone D. | Schmitz, Andrea | Theurillat, Regula | Thormann, W (Wolfgang) | Mevissen, Meike
Objective—To identify and characterize cytochrome P450 enzymes (CYPs) responsible for the metabolism of racemic ketamine in 3 mammalian species in vitro by use of chemical inhibitors and antibodies. Sample—Human, canine, and equine liver microsomes and human single CYP3A4 and CYP2C9 and their canine orthologs. Procedures—Chemical inhibitors selective for human CYP enzymes and anti-CYP antibodies were incubated with racemic ketamine and liver microsomes or specific CYPs. Ketamine N-demethylation to norketamine was determined via enantioselective capillary electrophoresis. Results—The general CYP inhibitor 1-aminobenzotriazole almost completely blocked ketamine metabolism in human and canine liver microsomes but not in equine microsomes. Chemical inhibition of norketamine formation was dependent on inhibitor concentration in most circumstances. For all 3 species, inhibitors of CYP3A4, CYP2A6, CYP2C19, CYP2B6, and CYP2C9 diminished N-demethylation of ketamine. Anti-CYP3A4, anti-CYP2C9, and anti-CYP2B6 antibodies also inhibited ketamine N-demethylation. Chemical inhibition was strongest with inhibitors of CYP2A6 and CYP2C19 in canine and equine microsomes and with the CYP3A4 inhibitor in human microsomes. No significant contribution of CYP2D6 to ketamine biotransformation was observed. Although the human CYP2C9 inhibitor blocked ketamine N-demethylation completely in the canine ortholog CYP2C21, a strong inhibition was also obtained by the chemical inhibitors of CYP2C19 and CYP2B6. Ketamine N-demethylation was stereoselective in single human CYP3A4 and canine CYP2C21 enzymes. Conclusions and Clinical Relevance—Human-specific inhibitors of CYP2A6, CYP2C19, CYP3A4, CYP2B6, and CYP2C9 diminished ketamine N-demethylation in dogs and horses. To address drug-drug interactions in these animal species, investigations with single CYPs are needed.
显示更多 [+] 显示较少 [-]Ontogeny, distributions and relative frequencies of the somatostatin-immunoreactive cells in the proventriculus of the chicken embryos with incubation periods
1999
Chang, J.W. | Lee, H.S. (Kyunsan University, Kyungsan (Korea Republic). Department of Biology, Faculty of Natural Science) | Ku, S.K. | Lee, J.H. (Kyungpook National University, Taegu (Korea Republic). Laboratory of Histology, College of Veterinary Medicine)
Ontogeny, distributions and relative frequencies of somatostatin-immunoreactive cells were investigated in the proventriculus of the chicken embryos with incubation periods. Samples were taken from 10 groups(10 days of incubation to hatching) and studied by immunogistochemical methods. The findings were as follows. Somatostatin-immunoreactive cells were observed from 12 days of incubation in the proventricular glands and after that increased with incubation periods. The first observation time of these cells in the epithelium were at 15 days of incubation in the basal portion but in 16 and 17 days of incubation, no immunoreactive cells were observed in the epithelium but after that a few immunoreactive cells were observed in the basal portion and gastric gland regions. The shpaes of these cells were spherical to spindle in the proventricular glands and spherical to round in the epithlium and gastric gland.
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