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1.
J Dairy Sci ; 107(3): 1821-1824, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38423729

RESUMO

Staphylococcus chromogenes TA showed significantly lower growth under iron-deprived conditions, and adding an iron supplement (lactoferrin or ferritin) resulted in no improvement in growth; in contrast, growth of S. chromogenes IM was significantly recovered with ferritin iron supplementation. OnlyStaphylococcus hominis strains originating from quarter milk were able to significantly utilize ferritin as an iron source to reverse the growth inhibition caused by chelating agent 2,2'-bipyridyl in varying degrees. Both S. chromogenes strains (IM and TA) and all S. hominis strains were unable to significantly use lactoferrin as an iron source for growth recovery.

2.
J Dairy Sci ; 105(12): 9995-10006, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36270870

RESUMO

Staphylococcus hominis, a member of the non-aureus staphylococci (NAS) group, is part of the human and animal microbiota. Although it has been isolated from multiple bovine-associated habitats, its relevance as a cause of bovine mastitis is currently not well described. To successfully colonize and proliferate in the bovine mammary gland, a bacterial species must be able to acquire iron from host iron-binding proteins. The aims of this study were (1) to assess the genetic diversity of S. hominis isolated from bovine quarter milk, rectal feces, and teat apices, and (2) to investigate the capacity of bovine S. hominis isolates belonging to these different habitats to utilize ferritin and lactoferrin as iron sources. To expand on an available collection of bovine S. hominis isolates (2 from quarter milk, 8 from rectal feces, and 19 from teat apices) from one commercial dairy herd, a subsequent single cross-sectional quarter milk sampling (n = 360) was performed on all lactating cows (n = 90) of the same herd. In total, 514 NAS isolates were recovered and identified by MALDI-TOF mass spectrometry; the 6 most prevalent NAS species were S. cohnii (33.9%), S. sciuri (16.7%), S. haemolyticus (16.3%), S. xylosus (9.6%), S. equorum (9.4%), and S. hominis (3.5%). A random amplified polymorphic DNA (RAPD) analysis was performed on 46 S. hominis isolates (19 from quarter milk, 8 from rectal feces, and 19 from teat apices). Eighteen distinct RAPD fingerprint groups were distinguished although we were unable to detect the presence of the same RAPD type in all 3 habitats. One S. hominis isolate of a distinct RAPD type unique to a specific habitat (8 from quarter milk, 3 from rectal feces, and 4 from teat apices) along with the quality control strain Staphylococcus aureus ATCC 25923 and 2 well-studied Staphylococcus chromogenes isolates ("IM" and "TA") were included in the phenotypical iron test. All isolates were grown in 4 types of media: iron-rich tryptic soy broth, iron-rich tryptic soy broth deferrated by 2,2'-bipyridyl, and deferrated tryptic soy broth supplemented with human recombinant lactoferrin or equine spleen-derived ferritin. The growth of the different strains was modified by the medium in which they were grown. Staphylococcus chromogenes TA showed significantly lower growth under iron-deprived conditions, and adding an iron supplement (lactoferrin or ferritin) resulted in no improvement in growth; in contrast, growth of S. chromogenes IM was significantly recovered with iron supplementation. Staphylococcus hominis strains from all 3 habitats were able to significantly utilize ferritin but not lactoferrin as an iron source to reverse the growth inhibition, in varying degrees, caused by the chelating agent 2,2'-bipyridyl.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Reto , Infecções Estafilocócicas , Animais , Bovinos , Feminino , Humanos , 2,2'-Dipiridil , Doenças dos Bovinos/microbiologia , Estudos Transversais , Fezes/microbiologia , Ferritinas , Variação Genética , Cavalos , Ferro , Lactação , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Leite/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico/veterinária , Infecções Estafilocócicas/veterinária , Staphylococcus hominis , Reto/microbiologia
3.
Acta Gastroenterol Belg ; 85(2): 403-405, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35709787

RESUMO

Carbohydrate antigen 19-9 (CA 19-9) is a biological marker used to diagnose and monitor the progression of various cancers. Elevated CA 19-9 has also been sporadically observed in Helicobacter pylori infected patients. Similar to H. pylori, animalhosted non-H. pylori Helicobacter (NHPH) species can induce gastroduodenal lesions in humans. We report the first case of CA 19-9 elevation related to H. suis gastritis and its normalisation after eradication. A CA 19-9 screening prescribed as part of a regular check up by the general practitioner was found elevated in a 68-year-old man presenting chronic dyspeptic symptoms. Medical investigations were negative for presence of neoplasia or biliary obstruction. Upper gastrointestinal endoscopy confirmed the presence of chronic gastritis and H. suis was identified in gastric biopsies. The standard treatment for H. pylori successfully eradicated H. suis with normalisation of CA 19-9 levels. In addition to H. pylori, infection with NHPH species should be considered as an additional cause of elevated CA19-9.


Assuntos
Gastrite , Infecções por Helicobacter , Helicobacter heilmannii , Helicobacter pylori , Infecções Intra-Abdominais , Idoso , Carboidratos , Gastrite/diagnóstico , Gastrite/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/patologia , Humanos , Masculino
4.
Acta Gastroenterol Belg ; 81(3): 436-438, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30350536

RESUMO

Helicobacter pylori is a Gram negative bacterium that has been associated with a wide variety of gastric pathologies in humans. Besides this well studied gastric pathogen, other Helicobacter spp. have been detected in a minority of patients with gastric disease. These species, also referred to as "H. heilmanii sensu lato" or "non Helicobacter pylori Helicobacter spp. (NHPH)", have a very fastidious nature which makes their in vitro isolation difficult. This group compromises several different Helicobacter species which naturally colonize the stomach of animals. In this article we present a case of a patient with severe gastritis in which H. felis was identified. The necrotic lesions observed at gastroscopy differ from the less active and less severe lesions generally associated with NHPH infections in human patients. The patient was successfully treated with a combination of amoxicillin, clarithromycin and pantoprazole. Infections with NHPH should be included in the differential diagnosis of gastritis when anatomopathological findings show an atypically shaped helicobacter.


Assuntos
Gastrite/diagnóstico , Gastroscopia , Infecções por Helicobacter/diagnóstico , Doença Aguda , Adulto , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Biópsia , Claritromicina/uso terapêutico , Quimioterapia Combinada , Gastrite/tratamento farmacológico , Gastrite/patologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/patologia , Helicobacter felis/genética , Humanos , Masculino , Pantoprazol/uso terapêutico , Reação em Cadeia da Polimerase , Inibidores da Bomba de Prótons/uso terapêutico , Tomografia Computadorizada por Raios X
5.
Aliment Pharmacol Ther ; 38(11-12): 1347-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24117797

RESUMO

BACKGROUND: There is increased proportional mortality from Parkinson's disease amongst livestock farmers. The hypokinesia of Parkinson's disease has been linked to Helicobacter pylori. H. suis is the most common zoonotic helicobacter in man. AIM: To compare the frequency of H. suis, relative to H. pylori, in gastric biopsies of patients with idiopathic parkinsonism (IP) and controls from gastroenterology services. METHODS: DNA extracts, archived at a Helicobacter Reference Laboratory, from IP patient and gastroenterology service biopsies were examined anonymously for H. suis, using species-specific RT-PCR. RESULTS: Relative risk of having H. suis in 60 IP patients compared with 256 controls was 10 times greater than that of having H. pylori. In patients with IP and controls, respectively, frequencies of H. suis were 27 (exact binomial 95% C.I. 15, 38) and 2 (0, 3)%, and of H. pylori, 28 (17, 40) and 16 (12, 21)%. Excess of H. suis in IP held when only the antral or corporal biopsy was considered. Of 16 IP patients with H. suis, 11 were from 19 with proven H. pylori eradication, 3 from 17 pre-H. pylori eradication, 2 from 24 H. pylori culture/PCR-negative. Frequency was different between groups (P = 0.001), greatest where H. pylori had been eradicated. Even without known exposure to anti-H. pylori therapy, H. suis was more frequent in IP patients (5/41) than in controls (1/155) (P = 0.002). Partial multilocus sequence typing confirmed that strains from IP patients (6) and control (1) differed from RT-PCR standard strain. CONCLUSIONS: Greater frequency of H. suis in idiopathic parkinsonism appears exaggerated following H. pylori eradication. Multilocus sequence testing comparison with porcine strains may clarify whether transmission is from pigs/porcine products or of human-adapted, H. suis-like, bacteria.


Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter heilmannii/isolamento & purificação , Helicobacter pylori/isolamento & purificação , Transtornos Parkinsonianos/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , DNA Bacteriano/análise , Feminino , Infecções por Helicobacter/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Risco , Adulto Jovem
6.
Poult Sci ; 92(5): 1202-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23571329

RESUMO

Cecal enteritis due to Brachyspira infections tends to be chronic in laying hens. Limited availability of antimicrobial drugs for use in laying hens emphasizes the need for alternative control measures. A broth microdilution method was used to determine the antimicrobial susceptibility of 20 Brachyspira intermedia field isolates from laying hen flocks to components of essential oils (EO). Minimal inhibitory concentration (MIC) distributions, obtained for 8 EO components, were all monomodal. Cinnamaldehyde had the lowest MIC values (40 to 80 mg/L), followed by nerolidol, capsaicin, carvacrol, and thymol (80 to 320 mg/L), eugenol (160 to 640 mg/L), and linalool (320 to 1,280 mg/L). The MIC ranges of piperine were mostly above the test range of 1,280 mg/L. In an in vivo experiment, coated trans-cinnamaldehyde was supplemented to the feed of rearing pullets. A completely randomized experimental design with 4 treatments and 3 replicates each (replicate = group of seven 1-d-old laying hen chickens) was applied. The negative and positive controls received a conventional feed during the whole trial. The positive controls were orally inoculated on 3 consecutive days (d 22, 23, and 24) with 1 mL of 1.0 × 10(8) cfu/mL of a B. intermedia field isolate. Two treatment groups (preventive and curative), identically inoculated, received the coated trans-cinnamaldehyde-supplemented feed (500 mg/kg of trans-cinnamaldehyde), the preventive group from d 1, the curative from d 25. On d 32, ceca were collected for bacteriologic Brachyspira enumeration. The mean enumeration of Brachyspira cells was decreased (P < 0.05) in the curative treated group versus the positive control group. The in vitro results of the present study demonstrate the potential of EO components as antimicrobials against poultry Brachyspira isolates, including isolates with acquired resistance for classic antimicrobial drugs. Reduction of Brachyspira colonization in young pullets was obtained, in a curative way, in an in vivo study using feed supplemented with coated trans-cinnamaldehyde. Further studies are necessary to investigate the mode of action of the coated trans-cinnamaldehyde in reducing Brachyspira colonization of the ceca.


Assuntos
Acroleína/análogos & derivados , Ração Animal , Brachyspira/efeitos dos fármacos , Galinhas , Infecções por Bactérias Gram-Negativas/veterinária , Óleos Voláteis/administração & dosagem , Doenças das Aves Domésticas/prevenção & controle , Acroleína/administração & dosagem , Ração Animal/análise , Animais , Bélgica , Ceco/microbiologia , Suplementos Nutricionais , Feminino , Infecções por Bactérias Gram-Negativas/prevenção & controle , Infecções por Bactérias Gram-Negativas/transmissão , Testes de Sensibilidade Microbiana/veterinária , Países Baixos , Óleos de Plantas/administração & dosagem , Doenças das Aves Domésticas/transmissão
7.
Avian Pathol ; 41(6): 563-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23237369

RESUMO

Aspergillosis caused by Aspergillus fumigatus seems to be more prevalent in some avian species than in others. We compared the development of aspergillosis in 8-month-old Gyr-Saker hybrid falcons and 8-month-old pigeons after a single intratracheal inoculation of different dosages of A. fumigatus conidia (10(7), 10(5) and 10(3)). Clinical signs, including vomiting, discoloration of the urates, loss of appetite and dyspnoea, were observed in four out of five falcons and in four out of five pigeons inoculated with 10(7) A. fumigatus conidia. Necropsy revealed the presence of granulomas in the air sacs and/or lungs in four out of five falcons and in four out of five pigeons in the high dosage group. A. fumigatus was isolated from these granulomas in three falcons and in three pigeons. The presence of fungal hyphae was detected with Periodic acid Shiff reagent staining in three out of five falcons and in three out of five pigeons in the high dosage group. Avian respiratory macrophages were clearly present in and around the fungal granulomas. In the other dosage groups, no granulomas, positive A. fumigatus cultures or fungal hyphae were present, except for one falcon in the middle dosage group in which a sterile granuloma without fungal hyphae was noticed. In conclusion, the study shows that adult falcons and pigeons are susceptible to aspergillosis after inoculation of a single dose of conidia intratracheally.


Assuntos
Aspergilose/veterinária , Aspergillus fumigatus/patogenicidade , Doenças das Aves/microbiologia , Columbidae , Falconiformes , Sacos Aéreos/microbiologia , Sacos Aéreos/patologia , Animais , Aspergilose/imunologia , Aspergilose/microbiologia , Aspergillus fumigatus/isolamento & purificação , Doenças das Aves/imunologia , Quimera , DNA Fúngico/genética , Suscetibilidade a Doenças , Genótipo , Granuloma/microbiologia , Granuloma/patologia , Granuloma/veterinária , Hifas , Larva , Pulmão/microbiologia , Pulmão/patologia , Masculino , Repetições de Microssatélites/genética , Mariposas/microbiologia , Polimorfismo Genético , Esporos Fúngicos , Virulência , Redução de Peso
8.
Int J Syst Evol Microbiol ; 62(Pt 2): 299-306, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21421932

RESUMO

Three gram-negative, microaerophilic bacteria, strains ASB1(T), ASB2 and ASB3, with a corkscrew-like morphology isolated from the gastric mucosa of cats were studied using a polyphasic taxonomic approach. The isolates grew on biphasic culture plates under microaerobic conditions at 37 °C and exhibited urease, oxidase and catalase activities. They were also able to grow in colonies on dry agar plates. Based on 16S rRNA gene sequence analysis, ASB1(T), ASB2 and ASB3 were identified as members of the genus Helicobacter and showed 98 to 99 % sequence similarity to strains of Helicobacter felis, Helicobacter bizzozeronii, 'Candidatus Helicobacter heilmannii', Helicobacter cynogastricus, Helicobacter baculiformis and Helicobacter salomonis, six related Helicobacter species previously detected in feline or canine gastric mucosa. Sequencing of the partial hsp60 gene demonstrated that ASB1(T), ASB2 and ASB3 constitute a separate taxon among the feline and canine Helicobacter species. The urease gene sequences of ASB1(T), ASB2 and ASB3 showed approximately 91 % similarity to those of 'Candidatus Helicobacter heilmannii'. Protein profiling, the absence of alkaline phosphatase activity and several other biochemical characteristics also allowed strains ASB1(T), ASB2 and ASB3 to be differentiated from other Helicobacter species of feline or canine gastric origin. The results of this polyphasic taxonomic study show that the cultured isolates constitute a new taxon corresponding to 'Candidatus Helicobacter heilmannii', which was previously demonstrated in the stomach of humans, wild felidae, cats and dogs. The name Helicobacter heilmannii sp. nov. is proposed for these isolates; the type strain is ASB1(T) (=DSM 24751 (T) =LMG 26292(T)) [corrected].


Assuntos
Doenças do Gato/microbiologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/veterinária , Helicobacter heilmannii/classificação , Helicobacter heilmannii/isolamento & purificação , Animais , Proteínas de Bactérias/química , Técnicas de Tipagem Bacteriana , Gatos , Chaperonina 60/genética , Chaperonina 60/metabolismo , DNA Bacteriano/análise , DNA Ribossômico/análise , Cães , Eletroforese/métodos , Genes de RNAr , Infecções por Helicobacter/microbiologia , Helicobacter heilmannii/genética , Helicobacter heilmannii/metabolismo , Humanos , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Urease/genética
9.
J Microbiol Methods ; 83(3): 335-40, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20851152

RESUMO

Limited reports are available on the growth response of Mycoplasma hyopneumoniae in Friis medium and the routinely used color changing units (CCU) assay has not yet been profoundly compared with other titration methods. Firstly, growth kinetics of 7 diverse M. hyopneumoniae isolates were followed by ATP luminometry in five Friis medium batches. Secondly, results of the CCU and ATP assays were compared hereby evaluating the methods. Growth curves of all isolates had log, stationary and senescence phases, and reached similar maximal titres when cultured in the same batch of Friis medium. Doubling times (Tds) of the isolates grown in slowly shaken cultures varied between 4.8 and 7.8 h. Maximal titres, Tds, growth phase in which the phenol red indicator turned from red to yellow due to acidification by mycoplasmal metabolism, and the length of the stationary phase varied depending on the Friis medium batch. The effect of static vs. shaking culture conditions on the Td depended on the isolate. ATP and CCU assays obtained similar growth curves, but when maximal levels were reached the CCU titre dropped earlier than the ATP titre. During log phase, CCU and ATP titres were strongly linearly linked. We developed a model enabling transformation of ATP into CCU titres or vice versa. The calculated amount of ATP per CCU (1.77 amol ATP/ml) indicated that the CCU assay likely underestimates the actual cell concentration. When titres were determined as means of 3 measurements, the ATP assay was 7 times more accurate and had 11-fold lower outliers than the CCU assay. Unlike the CCU assay, luminometry only requires one measurement to obtain sufficient accuracy. It was concluded that the ATP assay constitutes a valuable robust alternative for reproducible real-time titre assessment of freshly grown M. hyopneumoniae cultures. It is faster, more accurate and time, work and cost efficient compared to the CCU assay. The assay is preferred to better standardise and describe M. hyopneumoniae cultures used in various experiments.


Assuntos
Medições Luminescentes/métodos , Mycoplasma hyopneumoniae/crescimento & desenvolvimento , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Animais , Meios de Cultura/metabolismo , Mycoplasma hyopneumoniae/química , Mycoplasma hyopneumoniae/metabolismo , Pneumonia Suína Micoplasmática/microbiologia , Suínos
10.
J Appl Microbiol ; 106(6): 1951-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19228252

RESUMO

AIMS: Adherence of Mycoplasma hyopneumoniae to the ciliated epithelial cells of the porcine respiratory tract is considered an important first step in the pathogenesis of enzootic pneumonia. It was the aim of this study to verify the usefulness of in vitro adhesion as a virulence marker. METHODS AND RESULTS: Adherence capacity to immobilized cilia from porcine tracheal epithelial cells of three low, two moderately and two highly virulent M. hyopneumoniae field isolates was determined by a microtitre plate adherence assay. CONCLUSIONS: No significant differences between the isolates were demonstrated. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that mechanisms other than adherence might be responsible for the observed differences in virulence of these field isolates or that the in vitro assay does not adequately reproduce in vivo adherence conditions.


Assuntos
Aderência Bacteriana/fisiologia , Cílios/microbiologia , Mycoplasma hyopneumoniae/patogenicidade , Doenças Respiratórias/veterinária , Traqueia/microbiologia , Animais , Células Epiteliais , Epitélio/microbiologia , Suínos , Traqueia/citologia
11.
Lab Anim ; 43(1): 46-52, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18987064

RESUMO

Salmonella Typhimurium infections in pigs pose an important human health hazard. One promising control measure is the development of live attenuated vaccine strains using defined knockout mutants. Preferably, screening of candidate knockout vaccine strains for attenuation should first be done in models allowing testing of a large number of strains. Thereafter, a limited number of selected strains should be further characterized in an experimental infection model in pigs. The aim of the present study was to develop such models. The invasive and proliferative characteristics of S. Typhimurium were assessed in both a non-polarized and a polarized porcine intestinal epithelial cell line. Neutrophils obtained from porcine blood were used to study the capacity of Salmonella to withstand killing by these phagocytes. The ability to induce an intestinal inflammatory response was investigated in a terminal intestinal loop model. The systemic phase of infection was mimicked by studying the uptake and intracellular survival of S. Typhimurium in porcine pulmonary alveolar macrophages and peripheral blood monocytes. These models should allow screening for attenuated strains. For further characterization, an experimental infection model was established, providing extensive data on the course of an oral infection and the optimal time points for colonization (day 5 postinoculation [pi]) and persistency (days 21-28 pi) in pigs. In conclusion, screening for virulence of S. Typhimurium strains with subsequent confirmation for a subset of strains in a well-defined experimental infection model would significantly reduce the number of experimental pigs required.


Assuntos
Salmonelose Animal/microbiologia , Salmonella typhimurium/patogenicidade , Suínos/microbiologia , Animais , Linhagem Celular , Contagem de Colônia Microbiana , Enterite/microbiologia , Células Epiteliais/microbiologia , Feminino , Leucócitos Mononucleares/microbiologia , Macrófagos Alveolares/microbiologia , Masculino , Modelos Animais , Neutrófilos/microbiologia , Salmonella typhimurium/isolamento & purificação , Virulência
12.
Int J Syst Evol Microbiol ; 58(Pt 6): 1350-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18523177

RESUMO

A new cultivation method was successfully applied for the in vitro isolation of a hitherto uncultured spiral Helicobacter species associated with ulceration of the non-glandular stomach and gastritis in pigs and formerly described as 'Candidatus Helicobacter suis'. Three isolates, HS1(T), HS2 and HS3, were subcultured from the stomach mucosa of three pigs after slaughter and were analysed using a polyphasic taxonomic approach. The novel isolates grew on biphasic culture plates or very moist agar bases in microaerobic conditions and exhibited urease, oxidase and catalase activities. Sequencing of the 16S rRNA gene, the 23S rRNA gene, the partial hsp60 gene and partial ureAB genes confirmed that the strains present in the gastric mucosa of pigs constituted a separate taxon, corresponding to 'Helicobacter heilmannii' type 1 strains as detected in the gastric mucosa of humans and other primates. For all genes sequenced, the highest sequence similarities were obtained with Helicobacter felis, Helicobacter bizzozeronii and Helicobacter salomonis, Helicobacter species isolated from the gastric mucosa of dogs and cats, which have also been detected in the human gastric mucosa and which are commonly referred to as 'Helicobacter heilmannii' type 2. SDS-PAGE of whole-cell proteins of strains HS1(T), HS2 and HS3 differentiated them from other Helicobacter species of gastric origin. The results of the polyphasic taxonomic analysis confirmed that the novel isolates constitute a novel taxon corresponding to 'Helicobacter heilmannii' type 1 strains from humans and to 'Candidatus H. suis' from pigs. The name Helicobacter suis sp. nov. is proposed for the novel isolates with the type strain HS1(T) (=LMG 23995(T)=DSM 19735(T)).


Assuntos
Mucosa Gástrica/microbiologia , Infecções por Helicobacter/veterinária , Helicobacter/isolamento & purificação , Doenças dos Suínos/microbiologia , Suínos/microbiologia , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Técnicas Bacteriológicas , Chaperonina 60/genética , Meios de Cultura , DNA Bacteriano/análise , Eletroforese em Gel de Poliacrilamida , Feminino , Gastrite/microbiologia , Gastrite/veterinária , Helicobacter/classificação , Helicobacter/genética , Helicobacter/fisiologia , Infecções por Helicobacter/microbiologia , Humanos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Urease/genética
13.
Int J Syst Evol Microbiol ; 58(Pt 2): 357-64, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18218931

RESUMO

A Gram-negative, microaerophilic slender rod, measuring approximately 10 mum long and approximately 1 microm wide, isolated from the gastric mucosa of a cat and designated strain M50(T), was subjected to a polyphasic taxonomic study. Despite its apparent lack of helical coils, the organism showed a corkscrew-like motion by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril coiled around the body. Strain M50(T) grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 37 degrees C, but not at 25 or 42 degrees C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed about 98 to 99 % sequence similarity to Helicobacter felis, Helicobacter bizzozeronii, Helicobacter salomonis, Helicobacter cynogastricus and 'Candidatus Helicobacter heilmannii', five highly related species previously detected in the feline or canine gastric mucosa. Protein profiling of strain M50(T) using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin. Additionally, the urease and HSP60 gene sequences of strain M50(T) were different from those of H. felis, H. bizzozeronii, H. salomonis, H. cynogastricus and 'Ca. H. heilmannii'. It is thus proposed that strain M50(T) (=LMG 23839(T)=CCUG 53816(T)) represents a novel species within this genus, for which the name Helicobacter baculiformis sp. nov. is proposed.


Assuntos
Doenças do Gato/microbiologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/veterinária , Helicobacter/classificação , Animais , Técnicas de Tipagem Bacteriana , Gatos , Chaperonina 60/genética , Chaperonina 60/metabolismo , DNA Bacteriano/análise , Genes de RNAr , Helicobacter/genética , Helicobacter/isolamento & purificação , Infecções por Helicobacter/microbiologia , Dados de Sequência Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Urease/genética , Urease/metabolismo
14.
Vet Microbiol ; 125(3-4): 333-40, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17644278

RESUMO

In the present study, an in vivo rabbit skin infection model was developed to reproduce the lesions caused by high and low virulence Staphylococcus aureus strains from rabbits. "O"-shaped dermal skin lesions were induced on the shaved flanks of anaesthetised rabbits using a tattoo pin and pincers. The induced lesions on the flanks of four groups of 10 rabbits were then inoculated by topical application of 0.1 ml of 10(8)cfu S. aureus bacteria. One group was inoculated with a typical high virulence (HV) S. aureus strain from rabbits, one group received an atypical HV strain and two groups were inoculated with low virulence (LV) strains. Five animals were kept as negative controls. The development, appearance and size of abscesses were scored daily for a period of 2 weeks. The infection model showed reproducible results for the different S. aureus inoculation groups. Inoculation of the skin with the typical HV strain resulted in significantly larger abscesses than those caused by the LV strains. The atypical HV strain caused abscesses of a size intermediate to that obtained with the HV and LV strains. In rabbits infected with LV strains, most of the lesions had healed by day 14 post-inoculation. The devised infection model is able to reliably reproduce the virulence properties of HV and LV S. aureus strains.


Assuntos
Abscesso/veterinária , Coelhos/microbiologia , Dermatopatias Bacterianas/veterinária , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/patogenicidade , Abscesso/microbiologia , Abscesso/patologia , Animais , Biópsia/veterinária , Modelos Animais de Doenças , Feminino , Histocitoquímica/veterinária , Masculino , Distribuição Aleatória , Dermatopatias Bacterianas/microbiologia , Dermatopatias Bacterianas/patologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Estatísticas não Paramétricas , Virulência
15.
J Comp Pathol ; 135(4): 226-36, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17069831

RESUMO

In contrast to Helicobacter(H.) pylori, little is known about the pathogenic mechanisms of gastric non-H. pylori Helicobacter species. Mongolian gerbils were inoculated intragastrically with H. felis or H. bizzozeronii and killed at different timepoints post-inoculation (p.i.), stomach tissue being taken for light and transmission electron microscopy (TEM) and polymerase chain reaction (PCR) analysis. Parietal cells (PCs), apoptosis, cell proliferation and nuclear factor-kappaB (NF-kappaB) activation were "visualized" immunohistochemically. Inflammation consisted of neutrophilic granulocytes, mainly in the antrum, and lymphocytic infiltrates around the limiting ridge and throughout the stomach mucosa and submucosa. From day 11 p.i. onwards, H. felis-inoculated animals showed moderate to severe loss of PCs extending from the limiting ridge into the fundus. Apoptotic cells, spiral bacteria, cell proliferation, and NF-kappaB activation were detected at the transition zone between affected and normal PCs. TEM revealed interaction of H. felis flagella with PCs and chief cells. Moreover, H. felis was seen in proximity to, and inside, necrotic cells. At 10 weeks p.i., some H. felis-infected gerbils showed complete loss of fundic glands, and mucous metaplasia of the epithelium. H. bizzozeronii, which made no flagellar contact with epithelial cells, was associated with only mild PC loss. The mechanism by which H. felis induces PC necrosis and apoptosis remains unclear. The observed flagellar contact and NF-kappaB activation may play an important role in H. felis-associated inflammation.


Assuntos
Mucosa Gástrica/microbiologia , Gerbillinae , Infecções por Helicobacter/patologia , Helicobacter felis , Helicobacter , Células Parietais Gástricas/microbiologia , Animais , Modelos Animais de Doenças , Feminino , Mucosa Gástrica/anatomia & histologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/induzido quimicamente , Técnicas Histológicas , Imuno-Histoquímica , Microscopia Eletrônica de Transmissão , Células Parietais Gástricas/patologia
16.
Vet Res Commun ; 30(7): 707-15, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17004035

RESUMO

The aim of the present study was to determine which Pasteurella and Mannheimia species are present in the upper respiratory tract of healthy calves with no history of antimicrobial treatment prior to sampling. The presence of subpopulations of tetracycline-resistant Pasteurellaceae was also investigated. Nasal swabs from 61 loose group-housed, clinically healthy calves, 1 to 4 months old, from 16 dairy herds were inoculated aerobically on a selective medium (Columbia agar with 5% ovine blood and 16 mg/L bacitracin) with or without 4 mg/L oxytetracycline (OTC). A total of 43 strains belonging to the family Pasteurellaceae were isolated from 38 calves (62.3%) out of 13 herds (81.3%). The predominant organisms were Pasteurella multocida subsp. multocida (57.4%), Mannheimia varigena (4.9%) and M. haemolytica (3.2%). Growth of Pasteurellaceae on the OTC-containing medium was seen only with samples from two herds (6 animals; 9.8%), and on only one farm this proved to be an OTC-resistant subpopulation. Minimum inhibitory concentration (MIC) determinations by means of agar dilution confirmed a low prevalence of OTC-resistant Pasteurellaceae, with overall MIC(50) and MIC(90) values of 0.25 and 32 mg/L, respectively. These data do not support the hypothesis that the relative high frequency of tetracycline-resistant P. multocida isolates from fatal cases of bovine respiratory disease is related to the presence of minor tetracycline-resistance subpopulations within this species.


Assuntos
Antibacterianos/farmacologia , Doenças dos Bovinos/tratamento farmacológico , Nasofaringe/microbiologia , Infecções por Pasteurellaceae/veterinária , Pasteurellaceae/efeitos dos fármacos , Resistência a Tetraciclina , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Contagem de Colônia Microbiana/veterinária , Relação Dose-Resposta a Droga , Mannheimia/efeitos dos fármacos , Testes de Sensibilidade Microbiana/veterinária , Pasteurella/efeitos dos fármacos , Infecções por Pasteurellaceae/tratamento farmacológico , Infecções por Pasteurellaceae/microbiologia , Prevalência
17.
Int J Syst Evol Microbiol ; 56(Pt 7): 1559-1564, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16825630

RESUMO

A Gram-negative, microaerophilic helical rod, isolated from the gastric mucosa of a dog and designated strain JKM4(T), was subjected to a polyphasic taxonomic study. The tightly coiled organism, measuring 10-18 mum long and up to 1 mum wide, was motile by means of multiple sheathed flagella located at both ends of the cell and by a periplasmic fibril running along the external side of the helix. Strain JKM4(T) grew preferably on biphasic culture plates or on very moist agar. Coccoid forms predominated in cultures older than 4 days as well as in growth obtained on dry agar plates. The strain grew at 30 and 37 degrees C, but not at 25 or 42 degrees C and exhibited urease, oxidase and catalase activities. On the basis of 16S rRNA gene sequence analysis, the novel isolate was identified as a member of the genus Helicobacter and showed > 97 % similarity to Helicobacter felis, Helicobacter bizzozeronii and Helicobacter salomonis, three species previously isolated from the canine gastric mucosa. Protein profiling of strain JKM4(T) using SDS-PAGE revealed a pattern different from those of other Helicobacter species of mammalian gastric origin and from Helicobacter canis. Additionally, the urease gene sequence of strain JKM4(T) was different from those of urease genes of H. felis, H. bizzozeronii, H. salomonis and "Candidatus Helicobacter heilmannii". It is thus proposed that strain JKM4(T) (=LMG 23188(T)) represents a novel species within this genus, Helicobacter cynogastricus sp. nov.


Assuntos
Doenças do Cão/microbiologia , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/veterinária , Helicobacter/classificação , Helicobacter/isolamento & purificação , Animais , Proteínas de Bactérias/análise , Proteínas de Bactérias/isolamento & purificação , Catalase/análise , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Cães , Eletroforese em Gel de Poliacrilamida , Flagelos/fisiologia , Genes de RNAr/genética , Helicobacter/citologia , Helicobacter/fisiologia , Dados de Sequência Molecular , Movimento , Oxirredutases/análise , Filogenia , Proteoma/análise , Proteoma/isolamento & purificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Temperatura , Urease/análise , Urease/genética
18.
Vet Res Commun ; 29(4): 271-9, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15751578

RESUMO

Gastric Helicobacter spp. have been described in a wide range of animal species, including dogs, cats, primates, swine, cattle and rodents. However, in lagomorphs--more specifically rabbits--gastric Helicobacter infections have never been reported. Biopsy specimens were collected from different stomach regions of 23 rabbits, including 10 pet rabbits, 10 industrial animals and 3 research animals. These were subjected to a PCR assay for the detection of Helicobacter DNA. Identification up to the species level was based on 16S rRNA sequence analysis and a recently developed multiplex PCR. Seven rabbits (four pet, one research animal and two industrial animals) tested positive in the Helicobacter genus-specific PCR in the stomach, with the corpus being predominantly positive. H. felis and H. salomonis, hitherto presumed to be naturally hosted by cats and dogs, were detected in three animals and one animal, respectively. One of these animals had been completely devoid of any form of contact with cats or dogs. A H. pullorum/H. rappini-like organism (96% 16S rDNA sequence similarity) was found in an industrially held rabbit. The helicobacters of the two remaining rabbits could not be identified up to the species level. To conclude, this is the first report on the occurrence of Helicobacter spp. in the stomach of rabbits. In view of the fact that H. felis and H. salomonis are put forward as having zoonotic potential, further research is necessary to investigate the implications of these findings not only for the rabbit but also for human health.


Assuntos
Helicobacter heilmannii/isolamento & purificação , Coelhos/microbiologia , Estômago/microbiologia , Animais , Reservatórios de Doenças , Helicobacter heilmannii/genética , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética
19.
Res Vet Sci ; 77(3): 187-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15276768

RESUMO

Mannheimia varigena was identified as the etiologic agent of meningitis in a young Belgian White Blue heifer calf. Species identification of the bacterium was done by phenotyping and molecularly confirmed by tDNA-PCR. Standard bacteriological examination might fail to differentiate species belonging to the genus Mannheimia.


Assuntos
Doenças dos Bovinos/microbiologia , Mannheimia/isolamento & purificação , Meningites Bacterianas/veterinária , Infecções por Pasteurellaceae/veterinária , Animais , Técnicas de Tipagem Bacteriana/veterinária , Bovinos , DNA Bacteriano/análise , Resistência Microbiana a Medicamentos/fisiologia , Evolução Fatal , Feminino , Mannheimia/classificação , Mannheimia/genética , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/microbiologia , Infecções por Pasteurellaceae/diagnóstico , Infecções por Pasteurellaceae/microbiologia , Reação em Cadeia da Polimerase/veterinária
20.
Appl Environ Microbiol ; 70(6): 3582-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15184160

RESUMO

The most common source of Salmonella infections in humans is food of poultry origin. Salmonella enterica serovar Enteritidis has a particular affinity for the contamination of the egg supply. In this study, the medium-chain fatty acids (MCFA), caproic, caprylic, and capric acid, were evaluated for the control of Salmonella serovar Enteritidis in chickens. All MCFA were growth inhibiting at low concentrations in vitro, with caproic acid being the most potent. Contact of Salmonella serovar Enteritidis with low concentrations of MCFA decreased invasion in the intestinal epithelial cell line T84. By using transcriptional fusions between the promoter of the regulatory gene of the Salmonella pathogenicity island I, hilA, and luxCDABE genes, it was shown that all MCFA decreased the expression of hilA, a key regulator related to the invasive capacity of Salmonella. The addition of caproic acid (3 g/kg of feed) to the feed of chicks led to a significant decrease in the level of colonization of ceca and internal organs by Salmonella serovar Enteritidis at 3 days after infection of 5-day-old chicks. These results suggest that MCFA have a synergistic ability to suppress the expression of the genes required for invasion and to reduce the numbers of bacteria in vivo. Thus, MCFA are potentially useful products for reducing the level of colonization of chicks and could ultimately aid in the reduction of the number of contaminated eggs in the food supply.


Assuntos
Galinhas/microbiologia , Ácidos Graxos/farmacologia , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella enteritidis/patogenicidade , Transativadores/efeitos dos fármacos , Animais , Proteínas de Bactérias/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Caproatos/farmacologia , Caprilatos/farmacologia , Linhagem Celular Tumoral , Contagem de Colônia Microbiana , Ácidos Decanoicos/farmacologia , Humanos , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/microbiologia , Salmonelose Animal/prevenção & controle , Salmonella enteritidis/efeitos dos fármacos , Transativadores/metabolismo
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