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Laboratory reference values for a group of captive Ball pythons (Python regius).
1996
Johnson J.H. | Benson P.A.
Activity of β-lactam antibiotics against certain microorganisms which cause mastitis in cows Texto completo
2016
Burmańczuk Artur | Kowalski Cezary | Roliński Zbigniew | Zań Rafał | Krasucka Dorota
Introduction: The objective of this study was to determine the current profile of bacteria responsible for the infection of the mammary gland and to assess their sensitivity to selected β-lactam antibiotics.
Mostrar más [+] Menos [-]Chlamydiae – what’s new? Texto completo
2020
Zaręba-Marchewka, Kinga | Szymańska-Czerwińska, Monika | Niemczuk, Krzysztof
Chlamydiae – what’s new? Texto completo
2020
Zaręba-Marchewka, Kinga | Szymańska-Czerwińska, Monika | Niemczuk, Krzysztof
This paper provides an overview of the current knowledge of chlamydiae. These intracellular microorganisms belonging to the Chlamydiaceae family are widely distributed throughout the world. Constant development of culture-independent approaches for characterisation of microbial genomes enables new discoveries in the field of Chlamydia. The number of new taxa is continuously increasing as well as the range of hosts. New species and genotypes are constantly being discovered, particularly new avian and reptilian agents, which are discussed in this article. Interestingly, wild animals are the main hosts for new Chlamydia species including different species of bird, turtle and snake. The availability of next-generation sequencing opens up a new prospect for research and leads to deeper knowledge of these interesting microorganisms about which much is still to discover.
Mostrar más [+] Menos [-]Chlamydiae – what’s new? Texto completo
2020
Zaręba-Marchewka Kinga | Szymańska-Czerwińska Monika | Niemczuk Krzysztof
This paper provides an overview of the current knowledge of chlamydiae. These intracellular microorganisms belonging to the Chlamydiaceae family are widely distributed throughout the world. Constant development of culture-independent approaches for characterisation of microbial genomes enables new discoveries in the field of Chlamydia. The number of new taxa is continuously increasing as well as the range of hosts. New species and genotypes are constantly being discovered, particularly new avian and reptilian agents, which are discussed in this article. Interestingly, wild animals are the main hosts for new Chlamydia species including different species of bird, turtle and snake. The availability of next-generation sequencing opens up a new prospect for research and leads to deeper knowledge of these interesting microorganisms about which much is still to discover.
Mostrar más [+] Menos [-]Genetic diversity of Campylobacter jejuni isolated from the poultry food chain Texto completo
2019
Wieczorek, Kinga | Osek, Jacek
Genetic diversity of Campylobacter jejuni isolated from the poultry food chain Texto completo
2019
Wieczorek, Kinga | Osek, Jacek
Introduction: Campylobacter jejuni is one of the most frequently reported causes of foodborne bacterial enteric disease worldwide. The main source of these microorganisms is contaminated food, especially of poultry origin. There are several molecular methods for differentiation of Campylobacter isolates at the subgenus level, and one of these is porA-typing based on the sequencing of the major outer-membrane protein (MOMP) encoding gene. The aim of the study was to test the molecular relationship of C. jejuni strains isolated at different points along the poultry food chain and assess the population structure of the isolates. Material and Methods: A total of 451 C. jejuni were used in the study, and a DNA fragment of 630 bp of the MOMP encoding gene was amplified and sequenced. Results: One hundred and ten sequence types were identified, with 69 (62.7%) unique to the isolates' origin and 30 not present in the database. The most prevalent nucleotide variant 1 was detected in 37 (8.2%) strains. These isolates were identified in all poultry sources tested, especially in faeces (15 isolates) but also in poultry carcasses and meat (11 isolates in each). Conclusion: The porA typing method was highly discriminative for C. jejuni of poultry origin since the Simpson's diversity index (D) achieved a value of 0.876, indicating considerable diversity in the bacterial population tested. The method may be further used for epidemiological investigation purposes.
Mostrar más [+] Menos [-]Genetic diversity of Campylobacter jejuni isolated from the poultry food chain Texto completo
2019
Wieczorek Kinga | Osek Jacek
Introduction:Campylobacter jejuni is one of the most frequently reported causes of foodborne bacterial enteric disease worldwide. The main source of these microorganisms is contaminated food, especially of poultry origin. There are several molecular methods for differentiation of Campylobacter isolates at the subgenus level, and one of these is porA-typing based on the sequencing of the major outer-membrane protein (MOMP) encoding gene. The aim of the study was to test the molecular relationship of C. jejuni strains isolated at different points along the poultry food chain and assess the population structure of the isolates.
Mostrar más [+] Menos [-]Multiplex real-time PCRs for detection of Salmonella, Listeria monocytogenes, and verotoxigenic Escherichia coli in carcasses of slaughtered animals Texto completo
2016
Denis, Edyta | Bielińska, Katarzyna | Wieczorek, Kinga | Osek, Jacek
Multiplex real-time PCRs for detection of Salmonella, Listeria monocytogenes, and verotoxigenic Escherichia coli in carcasses of slaughtered animals Texto completo
2016
Denis, Edyta | Bielińska, Katarzyna | Wieczorek, Kinga | Osek, Jacek
Introduction: The study objective was to develop and evaluate a new TaqMan multiplex real-time PCR method for Salmonella, L. monocytogenes, and verotoxigenic Escherichia coli (VTEC) detection in slaughtered animal carcasses.Material and Methods: The procedure included an enrichment step, DNA extraction, and two multiplex real-time PCRs. The first PCR detected the invA and hly genes of Salmonella and L. monocytogenes respectively, the second the vtx1, vtx2, and eae genes of VTEC.Results: The validation of this method resulted in 100% relative sensitivity, specificity, and accuracy as compared to the reference ISO methods. The limit of detection per swab sample was established at 1 cfu for Salmonella and L. monocytogenes and 2 cfu for VTEC. The authors analysed 265 slaughterhouse-collected swabs from cattle, pig, and poultry carcasses. Among 125 from cattle, 51 were positive for VTEC, 29 for Salmonella, and 1 for L. monocytogenes. Among swabs from pig carcasses (n = 95), three, two, and one sample were positive for these pathogens respectively. None of the microorganisms tested for was identified in 45 samples of poultry origin.Conclusion: The obtained results showed that the method developed can rapidly identify the main bacterial pathogens that may contaminate carcasses of food-producing animals.
Mostrar más [+] Menos [-]Multiplex real-time PCRs for detection of Salmonella, Listeria monocytogenes, and verotoxigenic Escherichia coli in carcasses of slaughtered animals Texto completo
2016
Denis Edyta | Bielińska Katarzyna | Wieczorek Kinga | Osek Jacek
Introduction: The study objective was to develop and evaluate a new TaqMan multiplex real-time PCR method for Salmonella, L. monocytogenes, and verotoxigenic Escherichia coli (VTEC) detection in slaughtered animal carcasses.
Mostrar más [+] Menos [-]Description of the bacterial microbiota of anal sacs in healthy dogs Texto completo
2021
Bergeron, Camylle C. | Costa, Marcio C. | Souza, Lucilene B de | Sauve, Frederic
The aim of the present study was to characterize the bacterial microbiota of anal sacs in healthy dogs using NGS. Swabs were used to sample the rectum and secretions from each anal sac in 15 healthy dogs. DNA was extracted from swabs and the V4 hypervariable region of the 16S rRNA gene was amplified and sequenced with Illumina MiSeq. Overall, 14 different bacterial phyla were identified in the rectum and in both anal sacs, the 5 main ones being Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, and Fusobacteria. The rectum had higher microbial diversity and richness than the left and right anal sacs. Community membership and structure significantly differed between the rectum and both anal sacs, but not between the right and the left anal sacs. This study showed that the diversity and richness of the bacterial microbiota of the anal sacs in dogs is greater than what has been reported in previous studies with culture-based methods. In conclusion, the bacterial microbiota of the anal sacs in dogs varies between individuals and differs from the rectal bacterial microbiota.
Mostrar más [+] Menos [-]Occurrence of some pathogenic microorganisms in kareish cheese and their public health significance Texto completo
2018
G. M. Hassan | Samia I. Afify
A number of 50 Ardeola ibis ibis birds were found harboring six nematodes species; Tetrameres species, Microtteramere species, Synhimantus invaginatus, Synhimantus equispeculatus, Ascaridia species, Paracamallanus species,and five species of trematodes; Euclinostomum heterostomum, Nephrostomum ramosum, Apharyngostrigea ibis, Apatemon gracilis and Centrocestus armatus. The most common infection by nematodes was (46%) in which highest infection rate Synhimantus invaginatus recorded (30 %) while the trematode infection was (24 %) and Apatemon gracilis was the most prevalent (16 %). Experimental infection of buff backed heron by encysted metacercaria (EMC) and exysted metacercaria (ExMC) of Clinostomum complanatum from freshwater fish Tilapia nilotica, resulted in adult worms formed after 6 days. Where the infection by EMC recorded higher worm burden (14-18 worm) and hatching percent (78%) while the infection by ExMC gave lower worm burden (7-10 worm / bird ) and hatching (48 %). In the present study, it is worthy to mention that buff backed heron act as final host model for Clinostomum complanatum and this will be helpful in further biological and immunological studies for this trematode to decrease its economic losses in fish intermediate host.Fifty random samples of Kareish cheese were collected from different localities in Bani-suef Governorate. All samples were examined chemically for acidity, salt and moisture percent and bacteriologicaly for the presence of Escherichia coli, Staphylococcus aureus, Enterococci, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, Salmonella and Shigella species. The obtained results revealed that the mean values of acidity, salt and moisture % were 1.63 ± 0.095,3.55 ± 0.299 and 58.54 ± 0.599 in the examined kareish cheese samples, respectively.Escherichia coli, Staphylococcus aureus, Enterococci, Bacillus cereus, Clostridium perfringens were recovered from 16 (32%), 12(24%), 46 (92%), 25 (50 %) and 3 (6%) with a mean value of 4.86x102 ±4.21x10 2, 4.84x 10 5 ± 2.91x10 5, 3.74x10 6±1.55x10 6, 7.08x10 4±2.61x10 4 and 9.5x10 1 ± 7.37x10 1 of the examined samples , respectively. Yersinia enterocolitica could be isolated from 12% of the examined samples. Salmonella and Shigella species could not be detected in any of the examined samples. The isolated Escherichia coli were examined for serological identification, Enterotoxigenicity and the susceptibility of the isolated serovars to various chemotherapeutic agents. The public health significance and economical importance of the isolated organisms and the recommendations to be followed in the processing, handling and storage of such dairy product were discussed
Mostrar más [+] Menos [-]Bacterial strains isolated from Jeotgal (salted seafood) induce maturation and cytokine production in mouse bone marrow-derived dendritic cells
2014
Moon, S.Y., eju National University, Jeju, Republic of Korea | Park, E.J., eju National University, Jeju, Republic of Korea | Joo, H.G., eju National University, Jeju, Republic of Korea
Jeotgal (salted seafood) has been one of major fermented foods in Korea for long time. Although there are many studies about Jeotgal in various aspects of food, its immunological importance on hosts has not been elucidated yet. In this study, we investigated if several bacteria isolated from Jeotgal may modulate the function of dendritic cells (DCs), powerful antigen-presenting cells equipped with special immunological capabilities. 4 Jeotgal bacteria were selected as representatives and used for experiments. To treat viable DCs, those bacteria were killed at 60¡� for 30 min. The viability of DCs treated with Jeotgal bacteria was verified and two isolates significantly induced high production of interleukin-12, a representative cell-mediated cytokine of DCs. Surface activation and maturation markers (MHC class II, CD40, CD86) of DCs were analyzed by flow cytometer. In addition, the treated DCs showed significantly high lymphocyte stimulatory capability compared to control DCs based on allogeneic mixed lymphocyte reactions. These observations suggest that Jeotgal isolates can function as immunostimulating bacteria in hosts, like Lactobacillus. Taken together, these experimental evidences may broaden the use of Jeotgal isolates in immunological fields in addition to as a fermented food.
Mostrar más [+] Menos [-]A method to quantify infectious airborne pathogens at concentrations below the threshold of quantification by culture Texto completo
2013
Cutler, Timothy D. | Wang, Chong | Hoff, Steven J. | Zimmerman, Jeffrey J.
In aerobiology, dose-response studies are used to estimate the risk of infection to a susceptible host presented by exposure to a specific dose of an airborne pathogen. In the research setting, host- and pathogen-specific factors that affect the dose-response continuum can be accounted for by experimental design, but the requirement to precisely determine the dose of infectious pathogen to which the host was exposed is often challenging. By definition, quantification of viable airborne pathogens is based on the culture of micro-organisms, but some airborne pathogens are transmissible at concentrations below the threshold of quantification by culture. In this paper we present an approach to the calculation of exposure dose at microbiologically unquantifiable levels using an application of the “continuous-stirred tank reactor (CSTR) model” and the validation of this approach using rhodamine B dye as a surrogate for aerosolized microbial pathogens in a dynamic aerosol toroid (DAT).
Mostrar más [+] Menos [-]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.
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