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why do so many calves die on modern dairy farms and what can we do about calf welfare in the future?poor bovine neonatal survival rates are an international animal welfare issue. the key modifiable risk factors associated with such loss are age at first calving in primiparae, calf breed, gender and gestation length and calving management. the primary causes of mortality in the perinatal period are calving problems, in particular dystocia, defined as both difficult and abnormal calvings. calf loss rates are rising on modern dairy farms in many countries internationally. high calf loss rates are ...201326479751
evolutionary diversification and characterization of the eubacterial gene family encoding dxr type ii, an alternative isoprenoid biosynthetic enzyme.isoprenoids constitute a vast family of natural compounds performing diverse and essential functions in all domains of life. in most eubacteria, isoprenoids are synthesized through the methylerythritol 4-phosphate (mep) pathway. the production of mep is usually catalyzed by deoxyxylulose 5-phosphate reductoisomerase (dxr-i) but a few organisms use an alternative dxr-like enzyme (dxr-ii).201324004839
brucella bior regulator defines a complex regulatory mechanism for bacterial biotin metabolism.the enzyme cofactor biotin (vitamin h or b7) is an energetically expensive molecule whose de novo biosynthesis requires 20 atp equivalents. it seems quite likely that diverse mechanisms have evolved to tightly regulate its biosynthesis. unlike the model regulator bira, a bifunctional biotin protein ligase with the capability of repressing the biotin biosynthetic pathway, bior has been recently reported by us as an alternative machinery and a new type of gntr family transcriptional factor that ca ...201323729648
the lysr-type transcription factor hbrl is a global regulator of iron homeostasis and porphyrin synthesis in rhodobacter capsulatus.the purple bacterium rhodobacter capsulatus is unique among rhodobacteriacae as it contains a putative iron response regulator (irr) but does not possess a copy of the ferric uptake regulator (fur). interestingly, an in-frame deletion mutant of irr shows no major role in iron homeostasis. instead, we showed that the previously identified activator of haem gene expression hbrl is a crucial regulator of iron homeostasis. we demonstrated that an hbrl deletion strain is unable to grow in iron-limite ...201324134691
detection, distribution and characterization of novel superoxide dismutases from yersinia enterocolitica biovar 1a.superoxide dismutases (sods) cause dismutation of superoxide radicals to hydrogen peroxide and oxygen. besides protecting the cells against oxidative damage by endogenously generated oxygen radicals, sods play an important role in intraphagocytic survival of pathogenic bacteria. the complete genome sequences of yersinia enterocolitica strains show presence of three different sod genes. however, not much is known about the types of sods present in y. enterocolitica, their characteristics and role ...201323704955
prevalence of bovine genital campylobacteriosis and trichomonosis of bulls in northern nigeria.a survey was conducted to determine the prevalence of campylobacteriosis and trichomonosis, and their concurrence with brucellosis, in cattle in three states of northern nigeria.201323927676
antimicrobial resistance and virulence: a successful or deleterious association in the bacterial world?hosts and bacteria have coevolved over millions of years, during which pathogenic bacteria have modified their virulence mechanisms to adapt to host defense systems. although the spread of pathogens has been hindered by the discovery and widespread use of antimicrobial agents, antimicrobial resistance has increased globally. the emergence of resistant bacteria has accelerated in recent years, mainly as a result of increased selective pressure. however, although antimicrobial resistance and bacte ...201323554414
bacterial protein n-glycosylation: new perspectives and applications.protein glycosylation is widespread throughout all three domains of life. bacterial protein n-glycosylation and its application to engineering recombinant glycoproteins continue to be actively studied. here, we focus on advances made in the last 2 years, including the characterization of novel bacterial n-glycosylation pathways, examination of pathway enzymes and evolution, biological roles of protein modification in the native host, and exploitation of the n-glycosylation pathways to create nov ...201323329827
characterization of an ntrx mutant of neisseria gonorrhoeae reveals a response regulator that controls expression of respiratory enzymes in oxidase-positive proteobacteria.ntryx is a sensor-histidine kinase/response regulator two-component system that has had limited characterization in a small number of alphaproteobacteria. phylogenetic analysis of the response regulator ntrx showed that this two-component system is extensively distributed across the bacterial domain, and it is present in a variety of betaproteobacteria, including the human pathogen neisseria gonorrhoeae. microarray analysis revealed that the expression of several components of the respiratory ch ...201323564168
analytical and theranostic applications of gold nanoparticles and multifunctional nanocomposites.gold nanoparticles (gnps) and gnp-based multifunctional nanocomposites are the subject of intensive studies and biomedical applications. this minireview summarizes our recent efforts in analytical and theranostic applications of engineered gnps and nanocomposites by using plasmonic properties of gnps and various optical techniques. specifically, we consider analytical biosensing; visualization and bioimaging of bacterial, mammalian, and plant cells; photodynamic treatment of pathogenic bacteria; ...201323471188
competition for zinc binding in the host-pathogen interaction.due to its favorable chemical properties, zinc is used as a structural or catalytic cofactor in a very large number of proteins. despite the apparent abundance of this metal in all cell types, the intracellular pool of loosely bound zinc ions available for biological exchanges is in the picomolar range and nearly all zinc is tightly bound to proteins. in addition, to limit bacterial growth, some zinc-sequestering proteins are produced by eukaryotic hosts in response to infections. therefore, to ...201324400228
transcriptional regulation by ferric uptake regulator (fur) in pathogenic bacteria.in the ancient anaerobic environment, ferrous iron (fe(2+)) was one of the first metal cofactors. oxygenation of the ancient world challenged bacteria to acquire the insoluble ferric iron (fe(3+)) and later to defend against reactive oxygen species (ros) generated by the fenton chemistry. to acquire fe(3+), bacteria produce low-molecular weight compounds, known as siderophores, which have extremely high affinity for fe(3+). however, during infection the host restricts iron from pathogens by prod ...201324106689
nitrite reductase nirbd is induced and plays an important role during in vitro dormancy of mycobacterium tuberculosis.mycobacterium tuberculosis is one of the strongest reducers of nitrate among all mycobacteria. reduction of nitrate to nitrite, mediated by nitrate reductase (narghji) of m. tuberculosis, is induced during the dormant stage, and the enzyme has a respiratory function in the absence of oxygen. nitrite reductase (nirbd) is also functional during aerobic growth when nitrite is the sole nitrogen source. however, the role of nirbd-mediated nitrite reduction during the dormancy is not yet characterized ...201323935045
helicobacter hepaticus, a new pathogenic species of the helicobacter genus: similarities and differences with h. pylori.helicobacter hepaticus was discovered in 1992 as a cause of liver cancer in the a/jcr mouse model. in susceptible mice, infection by h. hepaticus causes chronic gastrointestinal inflammation leading to neoplasia. it can also cause morphological changes in breast-glands leading to neoplasm and adenocarcinoma in mouse models. studies performed on humans have revealed that h. hepaticus may also be a human pathogen since infection by h. hepaticus can be associated with cholecystitis, cholelithiasis ...201324475322
mntabc and mnth contribute to systemic staphylococcus aureus infection by competing with calprotectin for nutrient manganese.during infection, vertebrates limit access to manganese and zinc, starving invading pathogens, such as staphylococcus aureus, of these essential metals in a process termed "nutritional immunity." the manganese and zinc binding protein calprotectin is a key component of the nutrient-withholding response, and mice lacking this protein do not sequester manganese from s. aureus liver abscesses. one potential mechanism utilized by s. aureus to minimize host-imposed manganese and zinc starvation is th ...201323817615
exploitation of bacterial n-linked glycosylation to develop a novel recombinant glycoconjugate vaccine against francisella tularensis.glycoconjugate-based vaccines have proved to be effective at producing long-lasting protection against numerous pathogens. here, we describe the application of bacterial protein glycan coupling technology (pgct) to generate a novel recombinant glycoconjugate vaccine. we demonstrate the conjugation of the francisella tularensis o-antigen to the pseudomonas aeruginosa carrier protein exotoxin a using the campylobacter jejuni pglb oligosaccharyltransferase. the resultant recombinant f. tularensis g ...201323697804
development and validation of a novel diagnostic test for human brucellosis using a glyco-engineered antigen coupled to magnetic beads.brucellosis is a highly contagious zoonosis and still a major human health problem in endemic areas of the world. although several diagnostic tools are available, most of them are difficult to implement especially in developing countries where complex health facilities are limited. taking advantage of the identical structure and composition of the brucella spp. and yersinia enterocolitica o:9 o-polysaccharide, we explored the application of a recombinant y. enterocolitica o:9-polysaccharide-prot ...201323459192
intracellularly induced cyclophilins play an important role in stress adaptation and virulence of brucella abortus.brucella is an intracellular bacterial pathogen that causes the worldwide zoonotic disease brucellosis. brucella virulence relies on its ability to transition to an intracellular lifestyle within host cells. thus, this pathogen must sense its intracellular localization and then reprogram gene expression for survival within the host cell. a comparative proteomic investigation was performed to identify differentially expressed proteins potentially relevant for brucella intracellular adaptation. tw ...201323230297
innate immune recognition of flagellin limits systemic persistence of brucella.brucella are facultative intracellular bacteria that cause chronic infections by limiting innate immune recognition. it is currently unknown whether brucella flic flagellin, the monomeric subunit of flagellar filament, is sensed by the host during infection. here, we used two mutants of brucella melitensis, either lacking or overexpressing flagellin, to show that flic hinders bacterial replication in vivo. the use of cells and mice genetically deficient for different components of inflammasomes ...201323227931
identification of burkholderia cenocepacia strain h111 virulence factors using nonmammalian infection hosts.burkholderia cenocepacia h111, a strain isolated from a cystic fibrosis patient, has been shown to effectively kill the nematode caenorhabditis elegans. we used the c. elegans model of infection to screen a mini-tn5 mutant library of b. cenocepacia h111 for attenuated virulence. of the approximately 5,500 b. cenocepacia h111 random mini-tn5 insertion mutants that were screened, 22 showed attenuated virulence in c. elegans. except for the quorum-sensing regulator cepr, none of the mutated genes c ...201323090963
identification of leptospira interrogans phospholipase c as a novel virulence factor responsible for intracellular free calcium ion elevation during macrophage death.leptospira-induced macrophage death has been confirmed to play a crucial role in pathogenesis of leptospirosis, a worldwide zoonotic infectious disease. intracellular free ca(2+) concentration ([ca(2+)]i) elevation induced by infection can cause cell death, but [ca(2+)]i changes and high [ca(2+)]i-induced death of macrophages due to infection of leptospira have not been previously reported.201324124502
a method for molecular analysis of catalase gene diversity in seawater.catalase plays an important role in the metabolism of marine bacteria and has potential impact on the marine environment. four pcr primers were designed to amplify the catalase gene fragments in marine bacteria by applying metagenomic dna from yellow sea surface water as the template. of the four reproducible target pcr products, the longest one with 900 bp were chosen for catalase gene library construction by the t-vector and the white escherichia coli colonies in the library was screened throu ...201324426153
first trimester typhoid fever with vertical transmission of salmonella typhi, an intracellular organism.we report a case in which placental abruption occurred at 16 weeks following first trimester diagnosis and treatment for typhoid fever. unexpectedly salmonella enterica serovar typhi (s. typhi) was found in fetal tissues at autopsy. using information from the murine model of typhoid fever in pregnancy, we draw parallels between s. typhi and l. monocytogenes to develop a plausible hypothesis to explain how this organism was able to cross the placenta in the first trimester to cause abruption, inf ...201324459469
characterization of a novel zinc transporter znua acquired by vibrio parahaemolyticus through horizontal gene transfer.vibrio parahaemolyticus is a clinically important foodborne pathogen that causes acute gastroenteritis worldwide. it has been shown that horizontal gene transfer (hgt) contributes significantly to virulence development of v. parahaemolyticus. in this study, we identified a novel znua homolog (vpa1307) that belongs to a novel subfamily of znua, a bacterial zinc transporter. the vpa1307 gene is located upstream of the v. parahaemolyticus pathogenicity island (vp-pais) in both tdh-positive and trh- ...201324133656
metagenome reveals potential microbial degradation of hydrocarbon coupled with sulfate reduction in an oil-immersed chimney from guaymas basin.deep-sea hydrothermal vent chimneys contain a high diversity of microorganisms, yet the metabolic activity and the ecological functions of the microbial communities remain largely unexplored. in this study, a metagenomic approach was applied to characterize the metabolic potential in a guaymas hydrothermal vent chimney and to conduct comparative genomic analysis among a variety of environments with sequenced metagenomes. complete clustering of functional gene categories with a comparative metage ...201323785357
functional genes to assess nitrogen cycling and aromatic hydrocarbon degradation: primers and processing matter.targeting sequencing to genes involved in key environmental processes, i.e., ecofunctional genes, provides an opportunity to sample nature's gene guilds to greater depth and help link community structure to process-level outcomes. vastly different approaches have been implemented for sequence processing and, ultimately, for taxonomic placement of these gene reads. the overall quality of next generation sequence analysis of functional genes is dependent on multiple steps and assumptions of unknow ...201324062736
relaxed cleavage specificity within the rele toxin family.bacterial type ii toxin-antitoxin systems are widespread in bacteria. among them, the rele toxin family is one of the most abundant. the rele(k-12) toxin of escherichia coli k-12 represents the paradigm for this family and has been extensively studied, both in vivo and in vitro. rele(k-12) is an endoribonuclease that cleaves mrnas that are translated by the ribosome machinery as these transcripts enter the a site. earlier in vivo reports showed that rele(k-12) cleaves preferentially in the 5'-en ...201323543711
evidence of bovine viral diarrhea, but absence of infectious bovine rhinotracheitis and bovine brucellosis in the endangered huemul deer (hippocamelus bisulcus) in chilean patagonia.we screened 18 endangered chilean huemul (hippocamelus bisulcus) for antibodies to infectious agents. we detected no antibody to bovine herpesvirus-1 (bhv-1) or brucella abortus (ba); two huemul had antibody to bovine viral diarrhea virus (bvdv). cattle (n=35) had antibody to bvdv and bhv-1 but not ba.201323778636
[construction of brucella abortus a19-delta virb12 mutant and evaluation of its protective efficacy against 2308 strain challenge in balb/c mice].a19-deltavirb12 deletion mutant of brucella abortus was constructed by using homologous recombination technology. balb/c mice were vaccinated intraperitoneally with the mutant to evaluate protective efficacy against brucella abortus 2308 challenge.201324617263
detection of volatile organic compounds in brucella abortus-seropositive bison.brucellosis is of great public health and economic importance worldwide. detection of brucellosis currently relies on serologic testing of an antibody response to brucella infection, which suffers from cross-sensitivities to other antibody responses. here we present a new method for identifying brucella exposure that is based on profiling volatile organic compounds (vocs) in exhaled breath. breath samples from brucella-seropositive bison and controls were chemically analyzed and demonstrated sta ...201324156543
brucella abortus induces collagen deposition and mmp-9 down-modulation in hepatic stellate cells via tgf-β1 production.in patients with active brucellosis, the liver is frequently affected by histopathologic lesions, such as granulomas, inflammatory infiltrations, and parenchymal necrosis. herein, we examine some potential mechanisms of liver damage in brucellosis. we demonstrate that brucella abortus infection inhibits matrix metalloproteinase-9 (mmp-9) secretion and induces collagen deposition and tissue inhibitor of matrix metalloproteinase-1 secretion induced by hepatic stellate cells (lx-2). these phenomena ...201324113459
serologic detection of antibodies to brucella spp. using a commercial elisa in cattle in grenada, west indies.bovine brucellosis, caused mainly by brucella abortus, a zoonotic bacterium, has been reported from many areas of the world, including central and south america, and the caribbean island state of trinidad and tobago. although brucellosis has been eradicated from domestic cattle in canada it still exists in one or two herds in the united states. serological tests are important in estimating prevalence of brucella exposure in order to target eradication programmes. in this study, serum samples fro ...201323959493
fixl-like sensor flbs of brucella abortus binds haem and is necessary for survival within eukaryotic cells.replication of brucella inside eukaryotic cells is essential for pathogenesis, and successful infection requires rapid adaptation to the intracellular milieu. close relatives of brucella use the two-component system fixlj to survive inside the host. we aimed to identify a homologous sensor in brucella abortus. a predicted protein with transmembrane and conserved histidine kinase domains was identified as the fix-like brucella sensor, flbs. although it lacks the pas domain, recombinant flbs binds ...201323954290
abortion and premature birth in cattle following vaccination with brucella abortus strain rb51.brucella abortus rb51 is the vaccine strain currently licensed for immunizing cattle against brucellosis in the united states. most cattle are vaccinated as heifer calves at 4-12 months of age. adult cattle may be vaccinated in selected high-risk situations. two herds of pregnant adult cattle in the brucellosis-endemic area of wyoming were vaccinated with a standard label dose (1.0-3.4 × 10(10) organisms) of rb51. reproductive losses in the vaccinated herds were 5.3% (herd a) and 0.6% (herd b) a ...201323942901
genetic stability of brucella abortus s19 and rb51 vaccine strains by multiple locus variable number tandem repeat analysis (mlva16).the aims of the present study were (i) to assess the in vitro genetic stability of s19 and rb51 brucella abortus vaccines strains and (ii) to evaluate the ability of multiple-locus variable-number tandem repeat (vntr) analysis (mlva) as a tool to be used in the quality control of live vaccines against brucellosis. sixty-three batches of commercial s19 (n=53) and rb51 (n=10) vaccines, produced between 2006 and 2009, were used in this study. s19 and rb51 vaccines were obtained from, respectively, ...201323933375
comparative brucella abortus antibody prevalence in cattle under contrasting husbandry practices in uganda.a study was conducted in the luwero and nakasongola districts in central uganda to determine and compare the prevalence and distribution of antibodies against brucella abortus in cattle under contrasting husbandry practices, using two serological tests. three hundred and fifteen serum samples were systematically sampled from 29 farms and subsequently tested using the rose bengal plate test (rbpt) and indirect antibody enzyme linked immunosorbent assay (i-elisa). the overall prevalence of antibod ...201323905210
the use of contraception as a disease management tool in wildlife.contraception offers potential as a tool for managing certain diseases in wildlife, most notably venereally transmitted diseases or diseases transmitted at parturition. brucellosis is an excellent example of an infectious disease present in wild populations that could potentially be managed through immunocontraception. previous studies in bison (bison bison) suggest that a single injection of gonacon (national wildlife research center, u.s. department of agriculture/animal and plant health inspe ...201324437094
protective effect of a dna vaccine containing an open reading frame with homology to an abc-type transporter present in the genomic island 3 of brucella abortus in balb/c mice.the immunogenicity of a dna vaccine containing an open reading frame (orf) of genomic island 3 (gi-3), specific for brucella abortus and brucella melitensis, has been examined. intramuscular injection of plasmid dna carrying the open reading frame with homology to an abc-type transporter (pv278a) into balb/c mice elicited both humoral and cellular immune responses. mice injected with pv278a had a dominant immunoglobulin g2a (igg2a) response. this dna vaccine elicited a t-cell-proliferative respo ...201323834811
investigating genetic diversity of brucella abortus and brucella melitensis in italy with mlva-16.despite the eradication of brucellosis from most of europe, the disease remains relatively common in a variety of livestock in southern european countries. it is therefore surprising that with such high prevalence rates, there have been few genetic characterizations of brucellosis outbreaks in this region. we conducted a genetic assessment of 206 isolates of brucella abortus and b. melitensis from italy using variable number tandem repeats (vntrs). we determined genetic diversity and geographic ...201323831636
evaluation of bison (bison bison) semen from yellowstone national park, montana, usa, bulls for brucella abortus shedding.to determine if bison (bison bison) bulls from yellowstone national park (ynp), montana, usa, shed an infective dose of brucella abortus in semen, 50 ynp bulls were captured on public lands in montana during the winter and early spring (april-may) of 2010 and 2011. the bulls were immobilized, and blood and semen samples were collected for serology and brucella culture. thirty-five bulls (70%) were antibody-positive, and b. abortus was cultured from semen in three (9%) of the 35 antibody-positive ...201323778628
evaluation of transmission of brucella abortus strain 19 in bison by intravaginal, intrauterine, and intraconjunctival inoculation.bovine brucellosis, caused by the bacterium brucella abortus, is endemic in bison (bison bison) and elk (cervus elaphus nelsoni) populations in the area of yellowstone national park, usa. two strategies have been proposed to reduce the risk of transmission of disease in bison: remote vaccination with the vaccine rb51, and the use of immunocontraception of bison to decrease shedding of organisms from infected females. the frequent occurrence of venereal transmission in bison would complicate eith ...201323778600
brucellosis in humans--etiology, diagnostics, clinical forms.brucellosis in humans is a zoonosis of greatly varied clinical image. it occurs on all inhabited continents. the course of the disease may be acute, sub-acute or chronic. the etiologic factors of brucellosis are small, aerobic gram-negative rods of the genus brucella, which currently contains ten species: b. abortus, b. suis, b. ovis, b. melitensis, b. canis, b. neotomae, b. pinnipedialis, b. ceti, b. microti and b. inopinata. in humans, the disease is caused mainly by: b. melitensis as the most ...201323772567
detection of antibodies against brucella abortus, leptospira spp., and apicomplexa protozoa in water buffaloes in the northeast of argentina.water buffalo industry has become a profitable activity worldwide, including the northeast of argentina (nea). however, research on diseases affecting this species is scarce. the aim of the present study was to detect antibodies against brucella abortus, leptospira spp., neospora caninum, toxoplasma gondii, and sarcocystis spp. in 500 water buffalo cows from five ranches (100 animals each) in the nea. serum samples were tested for b. abortus by fluorescence polarization assay, leptospira spp. by ...201323765549
a duplex pcr for rapid and simultaneous detection of brucella spp. in human blood samples.to design a duplex pcr for rapid and simultaneous detection of brucella species. in human blood samples.201323711705
protection to respiratory challenge of brucella abortus strain 2308 in the lung.brucella is amongst the top 5 causes of zoonotic disease worldwide. infection is through ingestion, inhalation or contact exposure. brucella is characterized as a class b pathogen by centers of disease control and prevention (cdc). currently, there are no efficacious vaccines available in people. currently available usda approved vaccines for animals include b. abortus strain rb51 and b. melitensis rev1. protection is mediated by a strong innate and cd4 th1, cd8 tc1 immune response. if protectiv ...201323845817
hidden behind autophagy: the unconventional roles of atg proteins.macroautophagy (hereafter referred to as autophagy) is an evolutionarily conserved intracellular catabolic transport route that generally allows the lysosomal degradation of cytoplasmic components, including bulk cytosol, protein aggregates, damaged or superfluous organelles and invading microbes. target structures are sequestered by double-membrane vesicles called autophagosomes, which are formed through the concerted action of the autophagy (atg)-related proteins. until recently it was assumed ...201323837619
integrating ecology with management to control wildlife brucellosis.bison (bison bison) and elk (cervus elaphus) in the greater yellowstone ecosystem have long been infected with brucella abortus. the continued culling of large numbers of yellowstone bison to reduce the risk of brucellosis transmission to cattle could negatively affect long-term conservation. a desirable management objective is to reduce the level of b. abortus infection while conserving wildlife populations. identifying the ecological factors that influence immune suppression and vulnerabilityt ...201323837381
the russian experience in brucellosis veterinary public health.russia has extensive experience in controlling brucellosis in large and small animals, based on systematic animal health and disease control measures, combined with the use of specific prophylaxis. widespread application of the live brucellosis vaccine brucella abortus strain 82 has led to a dramatic reduction in the prevalence of brucellosis. among the distinctive properties of this vaccine are weak agglutinogenicity and high anti-epizootic efficacy, which allow differentiation between infected ...201323837380
pathogenesis and pathobiology of zoonotic brucellosis in humans.although human brucellosis has protean clinical manifestations, affected tissues usually exhibit signs of inflammation. the cellular and molecular bases of some immunopathological phenomena probably involved in the pathogenesis of infection with brucellae have been elucidated recently. human osteoblasts and fibroblast-like synoviocytes produce cytokines, chemokines and matrix metalloproteinases in response to infection with brucellae and/or to stimulation by brucellae-infected monocytes. in turn ...201323837370
an ecological perspective on brucella abortus in the western united states.after a hiatus during the 1990s, outbreaks of brucella abortus in cattle are occurring more frequently in some of the western states of the united states, namely, montana, wyoming and idaho. this increase is coincidentwith increasing brucellosis seroprevalence in elk (cervus elaphus), which is correlated with elk density. vaccines are a seductive solution, but their use in wildlife systems remains limited by logistical, financial, and scientific constraints. cattle vaccination is ongoing in the ...201323837367
risks of brucella abortus spillover in the greater yellowstone area.recurrent spillover of brucella abortus from wildlife reservoirs to domestic cattle in the greater yellowstone area (gya) has prevented the united states from completely eradicating bovine brucellosis. risks to cattle are a function of the size and location of wildlife and livestock populations, the degree and nature of spatio-temporal interactions between the various hosts, the level of disease in wildlife, and the susceptibility of livestock herds. while the brucellosis prevalence in wild, fre ...201323837366
epidemiology of brucellosis in domestic animals caused by brucella melitensis, brucella suis and brucella abortus.brucellosis is a disease that causes severe economic losses for livestock farms worldwide. brucella melitensis, b. abortus and b. suis, which are transmitted between animals both vertically and horizontally, cause abortion and infertility in their primary natural hosts - goats and sheep (b. melitensis), cows (b. abortus) and sows (b. suis). brucella spp. infect not only their preferred hosts but also other domestic and wild animal species, which in turn can act as reservoirs of the disease for o ...201323837364
evaluation of brucella abortus s19 vaccines commercialized in brazil: immunogenicity, residual virulence and mlva15 genotyping.live attenuated brucella abortus s19 is the most effective vaccine against brucellosis in cattle. the assessment of the immunological parameters is essential to guarantee the biological quality of live anti-bacteria vaccines. the evaluation of genetic stability of live bacterial vaccines is also important in quality control. the aims of the present study were to compare (i) the immunogenicity and residual virulence, and (ii) the genotypic profile (mlva15) of the eight s19 vaccines commercialized ...201323664986
male rats transmit brucella abortus biotype 1 through sexual intercourse.the aim of this study was to evaluate transmission of brucella abortus biotype 1 via sexual intercourse in rats. male and female virgin sprague-dawley (sd) rats were experimentally infected intraperitoneally with 1×10(9)colony forming units (cfu) of b. abortus biotype 1, a korean bovine isolate. at 14 days after infection, infected male rats (n=10) were housed with uninfected female rats (n=10) and infected female rats (n=10) were housed with uninfected male rats (n=10) for a period of one month ...201323664185
the ferrous iron transporter ftrabcd is required for the virulence of brucella abortus 2308 in mice.iron transport has been linked to the virulence of brucella strains in both natural and experimental hosts. the genes designated bab2_0837-0840 in the brucella abortus 2308 genome sequence are predicted to encode a cupii-type ferrous iron transporter homologous to the ftrabcd transporter recently described in bordetella. to study the role of the brucella ftrabcd in iron transport, an isogenic ftra mutant was constructed from b. abortus 2308. compared with the parental strain, the b. abortus ftra ...201323647104
[establishment and preliminary application of a quantitative real-time pcr method for detecting the transcriptions of th1/th2 cytokines in raw264.7 cells].to establish a quantitative real-time pcr method to detect the transcriptions of th1/th2 cytokines in raw264.7 cells.201323643175
molecular strain typing of brucella abortus isolates from italy by two vntr allele sizing technologies.brucellosis, one of the most important re-emerging zoonoses in many countries, is caused by bacteria belonging to the genus brucella. furthermore these bacteria represent potential biological warfare agents and the identification of species and biovars of field strains may be crucial for tracing back source of infection, allowing to discriminate naturally occurring outbreaks instead of bioterrorist events. in the last years, multiple-locus variable-number tandem repeat analysis (mlva) has been p ...201323585050
epidemiologic relatedness between brucella abortus isolates from livestock and wildlife in south korea.to investigate the epidemiologic relatedness of brucella abortus isolates from chinese water deer (hydropotes inermis) and goral (naemorhedus goral raddeanus) in 2010-2011, 22l isolates from livestock (including domestic elk, cervus canadensis) were analyzed using the multilocus variable-number tandem repeats analysis. in the clustering analysis, korean b. abortus isolates were divided into 40 genotypes by 18 markers, and 2 b. abortus isolates from wildlife were clustered with those of domestic ...201323568927
use of serology and bacterial culture to determine prevalence of brucella spp. in feral swine (sus scrofa) in proximity to a beef cattle herd positive for brucella suis and brucella abortus.using serology and bacterial culture, we determined the prevalence of brucella spp. and the antibody to brucella spp. in a feral swine (sus scrofa) population in proximity to a cattle herd that was culture positive for brucella abortus and brucella suis in north-central texas, usa. during a prospective cross-sectional quantitative study in april 2005, we collected blood and tissue samples from 40 feral swine within a 30-km radius of the infected herd. serum samples were tested by the rose bengal ...201323568896
seroprevalence and risk factors associated with brucellosis as a professional hazard in pakistan.the present study was conducted to determine the seroprevalence and identify risk factors associated with brucellosis in humans at high risk in the potohar plateau of northeastern pakistan. a total of 262 serum samples were collected from persons of different occupational groups: veterinary personnel, milkers, abattoir workers, livestock farmers, and others (drivers, security guards, housewives). data related to gender, age, occupation, contact with animals, brucellosis-related symptoms, consump ...201323560424
the two-component systems prrba and ntryx co-ordinately regulate the adaptation of brucella abortus to an oxygen-limited environment.brucella is the causative agent of the zoonotic disease brucellosis, which is endemic in many parts of the world. the success of brucella as pathogen relies in its ability to adapt to the harsh environmental conditions found in mammalian hosts. one of its main adaptations is the induction of the expression of different genes involved in respiration at low oxygen tension. in this report we describe a regulatory network involved in this adaptation. we show that brucella abortus prrba is a function ...201323527685
inactivation of the abc transporter atpase gene in brucella abortus strain 2308 attenuated the virulence of the bacteria.brucella abortus is a gram-negative, facultative intracellular bacterial pathogen of human and other animals. brucella lipopolysaccharide has been identified as an important virulence factor. in this study, the abc transporter atpase gene (bab1_0542) of b. abortus strain s2308 was inactivated by deleting a 446-bp fragment from the gene, thereby generating the mutant strain, s2308δatp. real time pcr analysis confirmed the inactivation of this gene with no polar effect on the transcription of adja ...201323507429
serologic survey of infectious diseases in populations of maned wolf (chrysocyon brachyurus) and crab-eating fox (cerdocyon thous) from aguas emendadas ecological station, brazil.domestic dogs are reservoirs for many infectious diseases and may represent a potential source of infection for wild canid populations. a serologic investigation of antibodies to toxoplasma gondii, neospora caninum, brucella abortus, and leptospira spp. was conducted on three maned wolves (chrysocyon brachyurus) and seven crab-eating foxes (cerdocyon thous), all free-living, at the aguas emendadas ecological station (esecae), federal district, brazil, between february and october 2006. out of th ...201323505716
importance of identification and typing of brucellae from west african cattle: a review.bovine brucellosis is an endemic infectious disease which can impact cattle productivity and welfare negatively, as well as human health. sufficient knowledge on its epidemiology, particularly on species and biotypes of brucella at national and/or regional scale are important to set up and implement efficient control measures against brucellosis in a "one health" perspective. the main objective of this review was to investigate available literature on strains of brucella in order to provide a st ...201323499188
critical role of asc inflammasomes and bacterial type iv secretion system in caspase-1 activation and host innate resistance to brucella abortus infection.pathogens are detected by innate immune receptors that, upon activation, orchestrate an appropriate immune response. recent studies revealed the intracellular signaling cascades involved in the tlr-initiated immune response to brucella abortus infection. however, no report has elucidated the role of inflammasome receptors in brucella recognition. therefore, we decided to investigate the function of nlrc4, nlrp3, and aim2 in sensing brucella. in this study, we showed that nlrc4 is not required to ...201323460746
evaluation of four dna extraction protocols for brucella abortus detection by pcr in tissues from experimentally infected cows with the 2308 strain.this study compared 4 protocols for dna extraction from homogenates of 6 different organs of cows infected with the brucella abortus 2308 strain. the extraction protocols compared were as follows: gt (guanidine isothiocyanate lysis), boom (gt lysis with the carrying suspension diatomaceous earth), pk (proteinase k lysis), and santos (lysis by boiling and freezing with liquid nitrogen). positive and negative gold standard reference groups were generated by classical bacteriological methods. all s ...201323421881
natural is711 insertion causing omp31 gene inactivation in brucella ovis.the present report describes an atypical brucella ovis strain (bo10) isolated from the epididymis and testis of an infected ram. macroscopic and microscopic lesions characteristic for the infection, including positive brucella immunostaining, were observed within lesions in the genital organs. compared to other isolates, strain bo10 required an additional day (a total of 96 hr) of incubation to form visible colonies, showed a distinct carbon source utilization profile, agglutinated only weakly w ...201323404477
sequential real-time pcr assays applied to identification of genomic signatures in formalin-fixed paraffin-embedded tissues: a case report about brucella-induced osteomyelitis.brucellosis is a zoonotic infection transmitted from animals to human by ingestion of infected food products, direct contact with an infected animal, or inhalation of aerosols. brucella infection-induced osteomyelitis may present only with nonspecific clinical and radiographic findings, mild elevations in serum inflammatory markers, as well as nonspecific histological changes. we studied a case of an iraqi war veteran with multifocal vertebral body and left iliac bone lesions on radio nucleotide ...201323356125
tandem repeats of the extracellular domain of matrix 2 influenza protein exposed in brucella lumazine synthase decameric carrier molecule induce protection in mice.the antigenic variation of influenza virus represents a major prevention problem. however, the ectodomain of the protein matrix 2 (m2e) is nearly invariant in all human influenza a strains and has been considered as a promising candidate for a broadly protective vaccine because antibodies to m2e are protective in animal models. in this work we evaluated the possible use of brucella abortus lumazine synthase protein (bls), a highly immunogenic decameric protein, as a carrier of the m2e peptide. c ...201323246552
lipopolysaccharide as a target for brucellosis vaccine design.the gram-negative bacteria of the genus brucella are facultative intracellular parasites that cause brucellosis, a world wide-distributed zoonotic disease that represents a serious problem for animal and human health. there is no human-to-human contagion and, since there is no human vaccine, animal vaccination is essential to control brucellosis. however, current vaccines (all developed empirically) do not provide 100% protection and are infectious in humans. attempts to generate new vaccines by ...201323219811
renal cyst infection caused by brucella abortus.a 49-year-old man with a medical history of polycystic kidney disease was presented to the emergency department with fever and left flank pain. abdominal examination revealed an enlarged and painful left kidney. the c-reactive protein level was significantly high and the magnetic resonance imaging revealed areas of abnormal intensity and fluid-fluid levels in renal cysts. brucella abortus was yielded from both blood and cyst fluid culture. standard therapy (rifampicin plus doxycycline) of brucel ...201323176669
redundant effects of ketamine on the pathogenesis and severity of brucella abortus infection.brucella abortus is an intracellular bacterium and leading to a serious debilitating disease known as brucellosis. ketamine is an anesthetic and a sedative that affects the immunomodulatory activities of various immune cells. the current study was to elucidate the role of ketamine in b. abortus infection, focusing on the phagocytic activity and immune response of macrophages. following incubation of murine macrophages with ketamine, the phagocytosis of b. abortus was markedly reduced compared wi ...201323107514
brucella abortus induces intracellular retention of mhc-i molecules in human macrophages down-modulating cytotoxic cd8(+) t cell responses.brucella abortus elicits a vigorous th1 immune response which activates cytotoxic t lymphocytes. however, b. abortus persists in its hosts in the presence of cd8(+) t cells, establishing a chronic infection. here, we report that b. abortus infection of human monocytes/macrophages inhibited the ifn-γ-induced mhc-i cell surface expression. this phenomenon was dependent on metabolically active viable bacteria. mhc-i down-modulation correlated with the development of diminished cd8(+) cytotoxic t ce ...201323107169
genetic analysis of the 3' untranslated region of the bovine slc11a1 gene reveals novel polymorphisms.polymorphisms in microsatellites at the 3' untranslated region (3'utr) of the slc11a1 (solute carrier family 11 member a1) gene have been associated with natural resistance to brucella abortus and mycobacterium bovis infection in livestock species. here, we carried out an individual genetic analysis of the two microsatellites present at the 3'utr slc11a1 gene in 254 bos taurus purebred, 125 b. indicus purebred and 54 b. taurus × b. indicus crossbred cattle. the genotyping by capillary electropho ...201323065223
structural basis for the inhibition of human lysozyme by plic from brucella abortus.lysozymes are the first line of defense for a diverse range of organisms that catalyze the degradation of bacterial peptidoglycan. gram-negative bacteria produce proteinaceous lysozyme inhibitors to protect themselves from the action of lysozymes. to date, mlic or plic (membrane-bound or periplasmic inhibitor of c-type lysozyme, respectively) has been found in various gram-negative bacteria. here, we report the crystal structures of brucella abortus plic and its complex with human c-type lysozym ...201324308818
phellinus baumii extract influences pathogenesis of brucella abortus in phagocyte by disrupting the phagocytic and intracellular trafficking pathway.to clarify the effects of phellinus baumii ethanol extract (pbe) on brucella abortus pathogenesis in phagocytes focusing on the phagocytic and intracellular trafficking pathway.201323163237
the role of a brucella abortus lipoprotein in intracellular replication and pathogenicity in experimentally infected mice.brucella abortus, the causative agent of brucellosis, can survive and replicate within host cells. understanding bacterial virulence factors and bacteria-host cell interactions is critical for controlling brucellosis. however, little is known regarding the pathogenic mechanisms of brucellosis. a lipoprotein mutant (gene bank id: 3339351) of b. abortus showed a lower rate of intracellular replication than did the wild-type strain in hela cells and raw 264.7 macrophages. the adherent activity of t ...201323006628
molecular insights into bacteroid development during rhizobium-legume symbiosis.rhizobial soil bacteria can form a symbiosis with legumes in which the bacteria fix atmospheric nitrogen into ammonia that can be utilized by the host. the plant, in turn, supplies the rhizobia with a carbon source. after infecting the host cell, the bacteria differentiate into a distinct bacteroid form, which is able to fix nitrogen. the bacterial baca protein is essential for bacteroid differentiation in legumes producing nodule-specific cysteine-rich peptides (ncrs), which induce the terminal ...201322998605
isolation of a field strain of brucella abortus from rb51-vaccinated- and brucellosis-seronegative bovine yearlings that calved normally.a study was carried out in pichucalco, chiapas (mexico) to determine whether recently calved cows or those that aborted shed brucella. serological diagnosis of brucellosis was made in all animals (209). six of the cows that calved normally and two that aborted underwent a bacteriological study of milk and vaginal exudate. brucella abortus was isolated from vaginal exudate samples in two 3- to 4-year-old seronegative first-birth cows that had calved normally. this was confirmed through bacteriolo ...201322956439
neutrophils: potential therapeutic targets in tularemia?the central role of neutrophils in innate immunity and host defense has long been recognized, and the ability of these cells to efficiently engulf and kill invading bacteria has been extensively studied, as has the role of neutrophil apoptosis in resolution of the inflammatory response. in the past few years additional immunoregulatory properties of neutrophils were discovered, and it is now clear that these cells play a much greater role in control of the immune response than was previously app ...201324409419
draft genome sequence of the live vaccine strain brucella abortus 82.vaccination is a crucial part of the brucellosis eradication programs worldwide. a live vaccine strain of brucella abortus 82 has been successfully used for the vaccination of cattle against brucellosis in the former soviet republics for the last 39 years. here, we report the genome sequence of brucella abortus 82.201324371203
the contribution of the glycine cleavage system to the pathogenesis of francisella tularensis.biosynthesis and acquisition of nutrients during infection are integral to pathogenesis. members of a metabolic pathway, the glycine cleavage system, have been identified in virulence screens of the intracellular bacterium francisella tularensis but their role in pathogenesis remains unknown. this system generates 5,10-methylenetetrahydrofolate, a precursor of amino acid and dna synthesis, from glycine degradation. to characterize this pathway, deletion of the gcvt homolog, an essential member o ...201324374051
the contribution of the glycine cleavage system to the pathogenesis of francisella tularensis.biosynthesis and acquisition of nutrients during infection are integral to pathogenesis. members of a metabolic pathway, the glycine cleavage system, have been identified in virulence screens of the intracellular bacterium francisella tularensis but their role in pathogenesis remains unknown. this system generates 5,10-methylenetetrahydrofolate, a precursor of amino acid and dna synthesis, from glycine degradation. to characterize this pathway, deletion of the gcvt homolog, an essential member o ...201324374051
nmr-monitored titration of acid-stress bacterial chaperone hdea reveals that asp and glu charge neutralization produces a loosened dimer structure in preparation for protein unfolding and chaperone activation.hdea is a periplasmic chaperone found in several gram-negative pathogenic bacteria that are linked to millions of cases of dysentery per year worldwide. after the protein becomes activated at low ph, it can bind to other periplasmic proteins, protecting them from aggregation when the bacteria travel through the stomach on their way to colonize the intestines. it has been argued that one of the major driving forces for hdea activation is the protonation of aspartate and glutamate side chains. the ...201324375557
nmr-monitored titration of acid-stress bacterial chaperone hdea reveals that asp and glu charge neutralization produces a loosened dimer structure in preparation for protein unfolding and chaperone activation.hdea is a periplasmic chaperone found in several gram-negative pathogenic bacteria that are linked to millions of cases of dysentery per year worldwide. after the protein becomes activated at low ph, it can bind to other periplasmic proteins, protecting them from aggregation when the bacteria travel through the stomach on their way to colonize the intestines. it has been argued that one of the major driving forces for hdea activation is the protonation of aspartate and glutamate side chains. the ...201324375557
entrance and survival of brucella pinnipedialis hooded seal strain in human macrophages and epithelial cells.marine mammal brucella spp. have been isolated from pinnipeds (b. pinnipedialis) and cetaceans (b. ceti) from around the world. although the zoonotic potential of marine mammal brucellae is largely unknown, reports of human disease exist. there are few studies of the mechanisms of bacterial intracellular invasion and multiplication involving the marine mammal brucella spp. we examined the infective capacity of two genetically different b. pinnipedialis strains (reference strain; ntct 12890 and a ...201324376851
in vivo identification and characterization of cd4⁺ cytotoxic t cells induced by virulent brucella abortus infection.cd4(+) t cells display a variety of helper functions necessary for an efficient adaptive immune response against bacterial invaders. this work reports the in vivo identification and characterization of murine cytotoxic cd4(+) t cells (cd4(+) ctl) during brucella abortus infection. these cd4(+) ctls express granzyme b and exhibit immunophenotypic features consistent with fully differentiated t cells. they express cd25, cd44, cd62l ,cd43 molecules at their surface and produce ifn-γ. moreover, thes ...201324367519
apoptosis-associated uncoupling of bone formation and resorption in osteomyelitis.the mechanisms underlying the destruction of bone tissue in osteomyelitis are only now being elucidated. while some of the tissue damage associated with osteomyelitis likely results from the direct actions of bacteria and infiltrating leukocytes, perhaps exacerbated by bacterial manipulation of leukocyte survival pathways, infection-induced bone loss predominantly results from an uncoupling of the activities of osteoblasts and osteoclasts. bacteria or their products can directly increase osteocl ...201324392356
16s rrna and omp31 gene based molecular characterization of field strains of b. melitensis from aborted foetus of goats in india.brucellosis is a reemerging infectious zoonotic disease of worldwide importance. in human, it is mainly caused by brucella melitensis, a natural pathogen for goats. in india, a large number of goats are reared in semi-intensive to intensive system within the close vicinity of human being. at present, there is no vaccination and control strategy for caprine brucellosis in the country. thus, to formulate an effective control strategy, the status of etiological agent is essential. to cope up with t ...201324453799
camelus dromedarius brucellosis and its public health associated risks in the afar national regional state in northeastern ethiopia.a cross-sectional study was carried out in four districts of the afar region in ethiopia to determine the prevalence of brucellosis in camels, and to identify risky practices that would facilitate the transmission of zoonoses to humans. this study involved testing 461 camels and interviewing 120 livestock owners. the modified rose bengal plate test (mrbpt) and complement fixation test (cft) were used as screening and confirmatory tests, respectively. spss 16 was used to analyze the overall preva ...201324344729
lps inmobilization on porous and non-porous supports as an approach for the isolation of anti-lps host-defense peptides.lipopolysaccharides (lpss) are the major molecular component of the outer membrane of gram-negative bacteria. this molecule is recognized as a sign of bacterial infection, responsible for the development of local inflammatory response and, in extreme cases, septic shock. unfortunately, despite substantial advances in the pathophysiology of sepsis, there is no efficacious therapy against this syndrome yet. as a consequence, septic shock syndrome continues to increase, reaching mortality rates ove ...201324409171
seroprevalence and potential risk factors for brucella spp. infection in traditional cattle, sheep and goats reared in urban, periurban and rural areas of niger.in niamey, niger, interactions within the interface between animals, humans and the environment induce a potential risk of brucellosis transmission between animals and from animals to humans. currently, little is known about the transmission of brucella in this context.201324358261
propolis: a wonder bees product and its pharmacological potentials.propolis is a natural resinous mixture produced by honey bees from substances collected from parts of plants, buds, and exudates. due to its waxy nature and mechanical properties, bees use propolis in the construction and repair of their hives for sealing openings and cracks and smoothing out the internal walls and as a protective barrier against external invaders like snakes, lizards, and so forth, or against weathering threats like wind and rain. bees gather propolis from different plants, in ...201324382957
systems biology analysis of brucella infected peyer's patch reveals rapid invasion with modest transient perturbations of the host transcriptome.brucella melitensis causes the most severe and acute symptoms of all brucella species in human beings and infects hosts primarily through the oral route. the epithelium covering domed villi of jejunal-ileal peyer's patches is an important site of entry for several pathogens, including brucella. here, we use the calf ligated ileal loop model to study temporal in vivo brucella-infected host molecular and morphological responses. our results document brucella bacteremia occurring within 30 min afte ...201324349118
biotyping and genotyping (mlva16) of brucella abortus isolated from cattle in brazil, 1977 to 2008.brucellosis is a worldwide distributed zoonosis that causes important economic losses to animal production. in brazil, information on the distribution of biovars and genotypes of brucella spp. is scarce or unavailable. this study aimed (i) to biotype and genotype 137 brazilian cattle isolates (from 1977 to 2008) of b. abortus and (ii) to analyze their distribution. b. abortus biovars 1, 2 and 3 (subgroup 3b) were confirmed and biovars 4 and 6 were first described in brazil. genotyping by the pan ...201324324670
bayesian estimation of the seroprevalence of brucellosis in humans and livestock in kyrgyzstan.kyrgyzstan reported 77.5 new cases of human brucellosis per 100,000 inhabitants in 2007, which is one of the highest incidences in the world. however, because this number is based on official records, it is very likely that the incidence is underreported. the diagnostic tests most commonly used in kyrgyzstan are the rose bengal test in ruminants and the huddleson test in humans. the sensitivity and specificity of these tests have never been evaluated under field conditions in kyrgyzstan, where t ...201324761732
evolutionary analysis of burkholderia pseudomallei identifies putative novel virulence genes, including a microbial regulator of host cell autophagy.burkholderia pseudomallei, the causative agent of melioidosis, contains a large pathogen genome (7.2 mb) with ∼2,000 genes of putative or unknown function. interactions with potential hosts and environmental factors may induce rapid adaptations in these b. pseudomallei genes, which can be discerned through evolutionary analysis of multiple b. pseudomallei genomes. here we show that several previously uncharacterized b. pseudomallei genes bearing genetic signatures of rapid adaptation (positive s ...201324097950
transmission of brucellosis from elk to cattle and bison, greater yellowstone area, u.s.a., 2002-2012.bovine brucellosis has been nearly eliminated from livestock in the united states. bison and elk in the greater yellowstone area remain reservoirs for the disease. during 1990-2002, no known cases occurred in greater yellowstone area livestock. since then, 17 transmission events from wildlife to livestock have been investigated.201324274092
unexpected brucella suis biovar 2 infection in a dairy cow, belgium. 201324274041
comparison of cytokine immune responses to brucella abortus and yersinia enterocolitica serotype o:9 infections in balb/c mice.brucella abortus and yersinia enterocolitica serotype o:9 serologically cross-react in the immune response with the host; therefore, our aim was to compare the immune responses to these two pathogens. we selected typical b. abortus and y. enterocolitica o:9 strains to study the cytokine immune response and the histopathological changes in livers and spleens of balb/c mice. the data showed the cytokine responses to the two strains of pathogens were different, where the average levels of granulocy ...201324042115
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