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Immunomodulatory effects of staphylococcal antigen and antigen-antibody complexes on canine mononuclear and polymorphonuclear leukocytes.
1994
DeBoer D.J.
Staphylococcal antigens and immune complexes (IC) prepared from antigen and hyperimmune canine serum were tested for their effects on certain functions of mononuclear (MN) and polymorphonuclear (PMN) leukocytes (cells) obtained from healthy dogs. The effect on MN cells was studied by determining the ability of antigen or IC to augment or inhibit mitogenesis induced by phytohemagglutinin (PHA). The effect of antigen or IC on PHA cells was studied by measurement of H2O2 production as an indicator of respiratory burst. Neither the antigen nor the IC, when cultured with MN cells, was mitogenic. Coincubation of antigen or IC with MN cells and PHA resulted in a concentration-dependent decrease in mitogenesis. The decreased mitogenesis could not be overcome by addition of excess PHA, and may in part have been related to toxic effects of the antigen or IC on MN cells. When MN cells were instead preincubated with antigen or IC, then washed and stimulated with PHA, there was still a concentration-dependent inhibition of mitogenesis, although toxicity to the cells was not observed. Low concentrations of staphylococcal antigen or IC stimulated slight H2O2 production by PHA cells. When PHA cells were coincubated with IC and another stimulus (opsonized zymosan or phorbol myristate acetate), IC appeared to augment phorbol myristate acetate-, but not zymosan-induced stimulation. These results suggest that staphylococcal antigens, either alone or complexed with antibody, have the ability to stimulate PMN cells and inhibit MN cell function. Such actions may have a role in the pathogenesis of recurrent staphylococcal infection in canine patients.
اظهر المزيد [+] اقل [-]Role of an intramammary device in protection against experimentally induced staphylococcal mastitis in ewes.
1993
Penades J.R. | Albizu I. | Baselga R. | Marco J. | Barberan M. | Amorena B.
An intramammary device (IMD) was adapted for use in ewes; this device was made of abraded poly. ethylene material (1.7 mm in diameter, 47 mm long) and formed a 15-mm-diameter loop in the gland cistern. The IMD was inserted in 1 gland in each of 43 ewes. A significant (P < 0.0001) increase in milk somatic cell count (SCC) was observed in glands provided with an IMD. This increase was attributable to an increase in neutrophil numbers and was observed during the first 12 weeks after insertion. The IMD had a protective effect against experimentally induced staphylococcal mastitis (Staphylococcus aureus and S epidermidis), although different milk SCC were required for protection from each bacterial species in most ewes (10(6) and 2 X 10(5) cells/ml, respectively). Histologic studies revealed that the IMD induced local squamous metaplasia in the glandular part of the lactiferous sinus. Erythrocytes were found in milk from glands provided with an IMD throughout the studied period (35 days of the 45-day lactation) and, in some cases, blood clots were observed during the first 2 weeks of lactation. Glands with IMD also had lower milk production and quality at 30 and 32 days of lactation. Eight ewes with IMD were studied throughout a subsequent lactation. Milk from the IMD-containing glands had an increase in SCC, as in the previous lactation period; did not contain blood clots or erythrocytes; and had normal composition (similar to that in glands without the IMD).
اظهر المزيد [+] اقل [-]Identification of Staphylococcus hyicus subsp hyicus of swine and poultry origin by API STAPH-IDENT system.
1994
Park C.K.
Pathological studies on exudative epidermitis in experimentally infected pigs-(1)-Macroscopical and histopathological observations.
1994
Oh K.S. | Lee C.S.
Investigation of high fatality among lambs in sheep farms in Pekan, Pahang, Malaysia
2016
Rosilawati K. | Nurul Faizah Z. | Saipul Bahari A. R.
This study was conducted to investigate the high mortality of young lambs in two sheep farms in Pekan, Pahang over a period of 3 years. Samples from postmortem of 1,451 lambs below one year of age by a farm veterinarian were submitted for laboratory diagnosis at the Bacteriology Section of the Regional Veterinary Diagnostic Laboratory in Kuantan. Escherichia coli is the most commonly recorded bacteria with 161 lambs diagnosed in 2013. In 2014 and 2015, there was a decrease in occurrence of E. coli related deaths, with 120 and 75lambs respectively. A total of 25% of the cases showed Escherichia coli positive by culture on blood agar and MacConkey agar, and confirmed by biochemical tests. A total of 21% of the cases were positive for staphylococcus sp, 3% and 6% for Streptococcus sp and Klebsiella pneumonia, respectively. Other bacteria were isolated in 45% of the cases. It was further noted that a total of 285 lambs between the ages of one to four months of age followed by 58 lambs (20%) less than one month old had E.coli isolation. It is also noteworthy that there were 10 lambs with E.coli infection in one to fourteen day-old lambs during the 3-year period from January 2013 to December 2015. This information was collated as a result of routine diagnosis of field cases submitted and with the intention of highlighting the common pathogens causing high mortality in local small ruminant farms so that preventive action may be taken for future farming ventures. E. coli infections or Colibacillosis is an important finding and indicator of poor management including poor nutrition, hygiene and environmental contamination which can reduce animal immunity and render it susceptible to other infections.
اظهر المزيد [+] اقل [-]Relationship between biofilm formation and the antimicrobial resistance in the Staphylococcus spp. isolated from animal and air
2009
Seo, Y.S., Seoul National University, Seoul, Republic of Korea | Lee, D.Y., Seoul National University, Seoul, Republic of Korea | Kang, M.L., Seoul National University, Seoul, Republic of Korea | Lee, W.J., Seoul National University, Seoul, Republic of Korea | Yoo, H.S., Seoul National University, Seoul, Republic of Korea
Biofilm has been described as a barrier, which produced by microorganisms to survive and protect themselves against various environments, like antibiotic agents. Staphylococcus spp. is a common cause of nosocomial and environmental infection. Thirty-six and thirty-five Staphylococci were isolated from animals and air, respectively. Based on the biofilm forming ability of the bacterium reported in our previous report, relationship between biofilm formation and antibiotic-resistance was investigated in this study. Regarding antibiotics susceptibility, cefazolin was the most effective agent to the bacteria. Strong biofilm-forming Staphylococcus spp. isolates might have a higher antibiotic resistance than weak biofilm isolates regardless of the presence of antibiotic resistance genes (p less than 0.05). This result suggested that the chemical complexity of the biofilm might increase the antibiotic resistance due to the decrease of antibiotic diffusion into cells through the extensive matrix.
اظهر المزيد [+] اقل [-]Microorganisms isolated from the corneal surface before and during topical cyclosporine treatment in dogs with keratoconjunctivitis sicca
1995
Salisbury, M.A.R. | Kaswan, R.L. | Brown, J.
The effect that topical administration of cyclosporine would have on the number and type of microorganisms isolated from the corneal surface of dogs with keratoconjunctivitis sicca was studied. Schirmer tear tests were performed on and corneal swab specimens were collected from 61 eyes of 31 dogs with keratoconjunctivitis sicca prior to and after 3, 6, and 12 months of treatment with cyclosporine. In eyes that responded to cyclosporine treatment (Schirmer tear test value increased by greater than or equal to 5 mm/min, compared with pretreatment value), the percentage of eyes from which bacteria were isolated after 3, 6, and 12 months of treatment was significantly (P < 0.001) less than the percentage from which bacteria were isolated prior to treatment. However, among eyes that did not respond to treatment, we did not detect a significant change over time in prevalence of bacteria or type of bacteria isolated. The percentage of eyes from which fungi were isolated decreased during treatment; however, the small number of eyes in which fungal culture results were initially positive precluded demonstration of a significant change. For all eyes, we did not detect any significant differences over time in the frequency with which specific bacterial genera were isolated, with the exception of beta-hemolytic Streptococcus spp. Opportunistic corneal infections were not detected even though none of the dogs received antibiotics. An increase in production of tears, which contain anti-infection proteins, was believed to be the primary factor responsible for the decrease in the percentage of eyes from which microorganisms could be isolated.
اظهر المزيد [+] اقل [-]Invastigation of 16S rRNA, mecA and nuc genes in coagulase-positive and negative Staphylococci by Real-Time PCR
2022
Aksakal, Abdulbaki | Onalan, Sukru | Okali̇n, Seyda Silan
Staphylococcus aureus is a Gram-positive and round-shaped bacterium. It is often positive for catalase and nitrate reduction. Pathogenic isolates support infections by producing protein toxins and the expression of a cell-surface protein virulence factors. Sepsis-related to methicillin-resistant S. aureus (MRSA) has significant morbidity and high mortality rates (15-30%). The methicillin resistance for S. aureus is coded with the MecA gene, while the methicillin sensitivity is coded with the Nuc gene, and they are chromosomal. Similarly, it is coded with the coagulase gene for S. aureus (Coa). In this study, the 16S rRNA gene identification by Real-Time PCR was investigated in forty S. aureus isolates, which were cultured at different times in terms of MIC and SIR tests. The isolates used in the study were determined at the gene level in terms of their differences in methicillin resistance gene (MecA), methicillin susceptibility gene (Nuc), coagulase gene (Coa) and intraspecies differences were examined.As a result of the study, Staphylococcus spp. yielded positive results with 16S rRNA gene-specific primers in all isolates. Real-Time PCR analysis of the isolates with SYBRGreen-based PCR analysis was performed with 16S rRNA gene-specific primers, and the samples were confirmed to be Staphylococcus. Analysis at the family level was followed by Coa, Nuc, and MecA gene Real-Time PCR results, and it was found that, in terms of Coa and Nuc genes, 19 isolates were positive and 21 isolates were negative. In terms of MecA gene, 16 isolates were positive according to the positive sigmoidal curves and to the single peak melting values, whereas 24 isolates were found to be negative.It is thought that this study will benefit the community by contributing to the rapid and effective treatment and diagnosis of infections caused by coagulase-positive/negative Staphylococci.
اظهر المزيد [+] اقل [-]Activation of swine plasminogen by staphylokinase of Staphylococcus hyicus subsp. hyicus
1999
Park, C.K. | Jang, E.H. (Kyungpook National University, Taegu (Korea Republic). College of Betrinary Medicine)
Swine plasminogen is not activated by staphylokinase of Staphylococcus aureus. In this study, the activation of swine plasminogen by staphylokinase of Staph hyicus subsp. hyicus was investigated and the effect of EDTA(disodium) on plasminogen activation was also studied. When the activation of swine plasminogen by staphylokinase of Staph hyicus subsp. hyicus was examined in fresh swine plasma, swine plasminogen could be weakly activated. However, when EDTA was added to the swine plasma, plasminogen activation was markedly enhanced, but this enhancement was not observed on bovine fibrin-dog plasminogen agar plate containing EDTA. Chicken and bovine plasminogens were not activated by staphylokinase of Staph hyicus subsp. hyicus. Using fresh swine plasma agar containing 0.07% EDTA, staphylokinase activity was detected in 96.3% of Staph hyicus subsp. hyicus strains isolated from pigs and in none of the chicken and bovine strains.
اظهر المزيد [+] اقل [-]Immunomodulatory effects of staphylococcal antigen and antigen-antibody complexes on canine mononuclear and polymorphonuclear leukocytes
1994
DeBoer, D.J.
Staphylococcal antigens and immune complexes (IC) prepared from antigen and hyperimmune canine serum were tested for their effects on certain functions of mononuclear (MN) and polymorphonuclear (PMN) leukocytes (cells) obtained from healthy dogs. The effect on MN cells was studied by determining the ability of antigen or IC to augment or inhibit mitogenesis induced by phytohemagglutinin (PHA). The effect of antigen or IC on PHA cells was studied by measurement of H2O2 production as an indicator of respiratory burst. Neither the antigen nor the IC, when cultured with MN cells, was mitogenic. Coincubation of antigen or IC with MN cells and PHA resulted in a concentration-dependent decrease in mitogenesis. The decreased mitogenesis could not be overcome by addition of excess PHA, and may in part have been related to toxic effects of the antigen or IC on MN cells. When MN cells were instead preincubated with antigen or IC, then washed and stimulated with PHA, there was still a concentration-dependent inhibition of mitogenesis, although toxicity to the cells was not observed. Low concentrations of staphylococcal antigen or IC stimulated slight H2O2 production by PHA cells. When PHA cells were coincubated with IC and another stimulus (opsonized zymosan or phorbol myristate acetate), IC appeared to augment phorbol myristate acetate-, but not zymosan-induced stimulation. These results suggest that staphylococcal antigens, either alone or complexed with antibody, have the ability to stimulate PMN cells and inhibit MN cell function. Such actions may have a role in the pathogenesis of recurrent staphylococcal infection in canine patients.
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