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71.
del Río ML Navas J Martín AJ Gutiérrez CB Rodríguez-Barbosa JI Rodríguez Ferri EF 《Veterinary research》2006,37(1):49-59
Bacteria have evolved a set of highly specialized proteins to capture iron in iron-depleted environments. The acquisition and uptake of iron present in the extracellular milieu of eukaryotic organisms is indispensable for the growth and survival of microbial pathogens in the course of infection. Haemophilus parasuis is the causative agent of Gl?sser disease, which is responsible for considerable financial losses in pig-rearing worldwide. To gain insight into the mechanisms involved in siderophore-mediated iron uptake in H. parasuis, genes in the H. parasuis ferric hydroxamate uptake (Fhu) region were amplified in the work being reported here. As has been described in A. pleuropneumoniae, an Fhu genomic region was also present in H. parasuis, being composed of four potential consecutive open reading frames (ORF) designated as fhuC, fhuD, fhuB, and fhuA, respectively. By immunoblotting, using a cross-reactive polyclonal antibody raised against Actinobacillus pleuropneumoniae FhuA protein, it was demonstrated that this protein was constitutively expressed in H. parasuis and its level of expression was not modified under conditions of restricted iron availability. This is the first report describing the presence of the fhu genes in H. parasuis. Our results indicate that FhuA protein expression is not affected under iron-restricted conditions, however, it is one of the targets of the humoral immune response. 相似文献
72.
Baker BJ Tyson GW Webb RI Flanagan J Hugenholtz P Allen EE Banfield JF 《Science (New York, N.Y.)》2006,314(5807):1933-1935
Novel, low-abundance microbial species can be easily overlooked in standard polymerase chain reaction (PCR)-based surveys. We used community genomic data obtained without PCR or cultivation to reconstruct DNA fragments bearing unusual 16S ribosomal RNA (rRNA) and protein-coding genes from organisms belonging to novel archaeal lineages. The organisms are minor components of all biofilms growing in pH 0.5 to 1.5 solutions within the Richmond Mine, California. Probes specific for 16S rRNA showed that the fraction less than 0.45 micrometers in diameter is dominated by these organisms. Transmission electron microscope images revealed that the cells are pleomorphic with unusual folded membrane protrusions and have apparent volumes of <0.006 cubic micrometer. 相似文献
73.
74.
DeRossi R Silva-Neto AB Pompermeyer CT Frazílio FO Jardim PH de Barros AC 《Research in veterinary science》2012,92(2):278-282
The aim of this study was to evaluate 3 doses of levobupivacaine (LB) epidurally administered in sheep. Six adult male 24-36 month-old sheep received levobupivacaine at 3 doses, LB05 (0.05 mg/kg), LB15 (0.15 mg/kg), and LB25 (0.25mg/kg), and saline solution into the lumbosacral epidural space. Heart rate, arterial blood pressure (systolic, diastolic, and mean), respiratory rate, rectal, and skin temperature, local anesthesia, and ataxia were determined before treatment and at predetermined intervals. The duration of local anesthesia was 30±5 min, 145±27 min, and 290±18 min for LB05, LB15, and LB25, respectively (P<0.05). Ataxia determined for LB05, LB15, or LB25 was similar to the anesthetic times. There was an increase in heart rate and reduction in arterial pressure in LB25 (P<0.05), whereas LB05 or LB15 did not affect these parameters. Lumbosacral epidural levobupivacaine is an appropriate choice for local anesthesia in sheep. 相似文献
75.
76.
A. R. Chaves M. P. de Campos M. B. L. Barros C. N. do Carmo I. D. F. Gremião S. A. Pereira T. M. P. Schubach 《Zoonoses and public health》2013,60(2):149-153
This study describes the epidemiological, clinical and mycological aspects of feline sporotrichosis cases attending the Laboratory of Clinical Research on Dermatozoonosis in Domestic Animals – Evandro Chagas Clinical Research Institute (LAPCLIN‐DERMZOO/IPEC/FIOCRUZ), from 1998 to 2005. It was possible to get in contact with 147 (19.2%) cat owners. One hundred and thirteen (76.9%) cats were male, 117 (79.6%) had no defined race and 87 (59.2%) were sexually intact. The age ranged from 72 to 216 months (median = 108 months). Nineteen cats were reassessed: eleven (57.8%) were male, thirteen (36.8%) were breed and fifteen (47.3%) castrated. Fourteen (52.6%) animals lived at home and did not roamed the streets. Seven (36.8%) had normal clinical findings and negative mycological examination. Twelve (63.1%) cats had skin lesions compatible with sporotrichosis. Thirty‐one (21%, n = 147) cats disappeared after abandoning treatment, 36 (24.5%, n = 147) were alive and 80 (54.4%, n = 147) had died. Causes of death informed by the owners were: sporotrichosis in 35 (43.7%, n = 80), accidental death in 27 (33.7%, n = 80) and other diseases in 18 (22.5%, n = 80). Withdrawal of treatment occurred mainly at the time of clinical improvement and may represent a serious obstacle to the control of sporotrichosis. 相似文献
77.
Santos OC Barros EM Brito MA Bastos Mdo C Dos Santos KR Giambiagi-Demarval M 《Veterinary microbiology》2008,130(1-2):134-140
Coagulase-negative staphylococci (CNS) have become the predominant pathogens causing bovine mastitis in many countries. CNS infections are associated with damage to milk secretory tissue of the mammary gland by increased connective tissue stroma, moderate increases of somatic cells count in milk and significant production decreases. These consequences impose serious economic losses for the farmers and the dairy industry. Routine veterinary laboratories do not usually identify CNS at the species level. Thereby, the aims of this study were to identify the most common staphylococcal pathogens involved in bovine mastitis using PCR-restriction fragment length polymorphism (RFLP) analysis of a partial groEL gene sequence and to compare our results with the identification carried out by the conventional method. A total of 54 isolates of Staphylococcus, involved in bovine mastitis, were analyzed by this method. The size and number of the fragments obtained by either AluI or HindIII/PvuII digestions made possible to form clear patterns differentiating, among the isolates, 11 of the most common species of animal staphylococcal pathogens. Most of the isolates clustered together with the reference strain of Staphylococcus chromogenes (28) and the type strain of Staphylococcus epidermidis (8). Besides, some isolates clustered together with the type strain of Staphylococcus aureus (5). All patterns were confirmed by the conventional biochemical method, showing concordant results. Thus, the PCR-RFLP of the groEL gene constitutes a reliable and reproducible molecular method for identification of CNS species responsible for bovine mastitis. 相似文献
78.
79.
Cardoso Daniel Barros Véras Robson Magno Liberal de Carvalho Francisco Fernando Ramos Magalhães André Luiz Rodrigues de Vasconcelos Gustavo Araújo Maciel Maria Inês Sucupira Madruga Marta Suely Urbano Stela Antas de Lima Silva Janaina 《Tropical animal health and production》2019,51(6):1515-1521
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the replacement of corn by cassava dregs (0, 33, 66, and 100%) in the diet of lamb on... 相似文献