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bench-to-bedside review: platelets and active immune functions - new clues for immunopathology?platelets display a number of properties besides the crucial function of repairing damaged vascular endothelium and stopping bleeding; these are exploited to benefit patients receiving platelet component transfusions, which might categorize them as innate immune cells. for example, platelets specialize in pro-inflammatory activities, and can secrete a large number of molecules, many of which display biological response modifier functions. platelets also express receptors for non-self-infectious ...201323998653
use of staged molecular analysis to determine causes of unexplained central nervous system infections.no agent is implicated in most central nervous system (cns) infections. to investigate cerebrospinal fluid samples from patients with cns infections of unknown cause in 1 hospital in taiwan, we used a staged molecular approach, incorporating techniques including multiplex masstag pcr, 16s rrna pcr, dna microarray, and high-throughput pyrosequencing. we determined the infectious agent for 31 (24%) of 131 previously negative samples. candidate pathogens were identified for 25 (27%) of 94 unexplain ...201323965845
transcriptional profiling of staphylococcus aureus during growth in 2 m nacl leads to clarification of physiological roles for kdp and ktr k+ uptake systems.staphylococcus aureus exhibits an unusually high level of osmotolerance and na(+) tolerance, properties that support survival in various host niches and in preserved foods. the genetic basis of these traits is not well understood. we compared the transcriptional profiles of s. aureus grown in complex medium with and without 2 m nacl. the stimulon for growth in high-osmolality media and na(+) included genes involved in uptake of k(+), other compatible solutes, sialic acid, and sugars; capsule bio ...201323963175
characterization of three novel adhesins of leptospira interrogans.we report cloning, expression, purification, and characterization of three predicted leptospiral membrane proteins (lic11360, lic11009, and lic11975). in silico analysis and proteinase k accessibility data suggest that these proteins might be surface exposed. we show that proteins encoded by lic11360, lic11009 and lic11975 genes interact with laminin in a dose-dependent and saturable manner. the proteins are referred to as leptospiral surface adhesions 23, 26, and 36 (lsa23, lsa26, and lsa36), r ...201323958908
human hemorrhagic pulmonary leptospirosis: pathological findings and pathophysiological correlations.leptospirosis is a re-emerging zoonosis with protean clinical manifestations. recently, the importance of pulmonary hemorrhage as a lethal complication of this disease has been recognized. in the present study, five human necropsies of leptospirosis (weil's syndrome) with extensive pulmonary manifestations were analysed, and the antibodies expressed in blood vessels and cells involved in ion and water transport were used, seeking to better understand the pathophysiology of the lung injury associ ...201323951234
genetic and molecular biological characterization of two homologous cher genes from leptospira interrogans.the leptospira interrogans genome encodes two copies of cher genes and each of them is able to complement for the swarming defective phenotype of escherichia coli cher null mutant rp1254 to certain extent, while over-expression of either of them inhibits the swarming of the chemotactic wild-type e. coli strain, rp437. therefore, both cher1 and cher2 ought to bear the methyltransferase activities, although cher1 has only one instead of two conserved basic amino acid residues located on the positi ...201323934012
contribution of leptospira, neospora caninum and bovine viral diarrhea virus to fetal loss of beef cattle in new zealand.the profitability of beef breeding farms in new zealand depends principally on optimal reproductive performance. the aim of this study was to estimate the impact of four major pathogens, bovine viral diarrhea virus (bvdv), neospora caninum (n. caninum), leptospira borgpetersenii serovar hardjo (hardjo), and leptospira interrogans serovar pomona (pomona), on rates of fetal loss in commercial beef breeding herds. farms reporting fetal loss were recruited, and a blood sample from aborting cows (cas ...201323932894
complement-mediated opsonization of invasive group a streptococcus pyogenes strain ap53 is regulated by the bacterial two-component cluster of virulence responder/sensor (covrs) system.group a streptococcus pyogenes (gas) strain ap53 is a primary isolate from a patient with necrotizing fasciitis. these ap53 cells contain an inactivating mutation in the sensor component of the cluster of virulence (cov) responder (r)/sensor (s) two-component gene regulatory system (covrs), which enhances the virulence of the primary strain, ap53/covr(+)s(-). however, specific mechanisms by which the covrs system regulates the survival of gas in humans are incomplete. here, we show a key role fo ...201323928307
identification of novel adhesins of m. tuberculosis h37rv using integrated approach of multiple computational algorithms and experimental analysis.pathogenic bacteria interacting with eukaryotic host express adhesins on their surface. these adhesins aid in bacterial attachment to the host cell receptors during colonization. a few adhesins such as heparin binding hemagglutinin adhesin (hbha), apa, malate synthase of m. tuberculosis have been identified using specific experimental interaction models based on the biological knowledge of the pathogen. in the present work, we carried out computational screening for adhesins of m. tuberculosis. ...201323922800
cryo-electron tomography: the challenge of doing structural biology in situ.electron microscopy played a key role in establishing cell biology as a discipline, by producing fundamental insights into cellular organization and ultrastructure. many seminal discoveries were made possible by the development of new sample preparation methods and imaging modalities. recent technical advances include sample vitrification that faithfully preserves molecular structures, three-dimensional imaging by electron tomography, and improved image-processing methods. these new techniques h ...201323918936
leptospiral lrua is required for virulence and modulates an interaction with mammalian apolipoprotein ai.leptospirosis is a worldwide zoonosis caused by spirochetes of the genus leptospira. while understanding of pathogenesis remains limited, the development of mutagenesis in leptospira has provided a powerful tool for identifying novel virulence factors. lrua is a lipoprotein that has been implicated in leptospiral uveitis as a target of the immune response. in this study, two lrua mutants, m754 and m765, generated by transposon mutagenesis from leptospira interrogans serovar manilae, were charact ...201323918777
a phylogenomic and molecular signature based approach for characterization of the phylum spirochaetes and its major clades: proposal for a taxonomic revision of the phylum.the spirochaetes species cause many important diseases including syphilis and lyme disease. except for their containing a distinctive endoflagella, no other molecular or biochemical characteristics are presently known that are specific for either all spirochaetes or its different families. we report detailed comparative and phylogenomic analyses of protein sequences from spirochaetes genomes to understand their evolutionary relationships and to identify molecular signatures for this group. these ...201323908650
prozone effects in microscopic agglutination tests for leptospirosis in the sera of mice infected with the pathogenic leptospira interrogans serovar canicola.mice experimentally infected with a pathogenic strain of leptospira interrogans serovar canicola produced false negative results (prozone effect) in a microscopic agglutination test (mat). this prozone effect occurred in several serum samples collected at different post-infection times, but it was more prominent in samples collected from seven-42 days post-infection and for 1:50 and 1:100 sample dilutions. this phenomenon was correlated with increased antibody titres in the early post-infection ...201323903987
bridging the gap between systems biology and synthetic biology.systems biology is an inter-disciplinary science that studies the complex interactions and the collective behavior of a cell or an organism. synthetic biology, as a technological subject, combines biological science and engineering, allowing the design and manipulation of a system for certain applications. both systems and synthetic biology have played important roles in the recent development of microbial platforms for energy, materials, and environmental applications. more importantly, systems ...201323898328
extracellular proteome analysis of leptospira interrogans serovar lai.abstract leptospirosis is one of the most important zoonoses. leptospira interrogans serovar lai is a pathogenic spirochete that is responsible for leptospirosis. extracellular proteins play an important role in the pathogenicity of this bacterium. in this study, l. interrogans serovar lai was grown in protein-free medium; the supernatant was collected and subsequently analyzed as the extracellular proteome. a total of 66 proteins with more than two unique peptides were detected by ms/ms, and 33 ...201323895271
sporadic urban leptospirosis.severe leptospirosis (weil syndrome) was diagnosed in an otherwise healthy environmental worker in baltimore alleys in late november 2010. he developed multiple organ failure but responded to antibiotic therapy and experienced a full recovery within 4 weeks. his diagnosis was confirmed by a rise in indirect hemagglutinin titer (acute 0, convalescent 400). the subject had close contact with baltimore alley rats; a similar epidemiologic exposure and location reported in an outbreak 15 years ago.201123882321
toll-like receptors in atherosclerosis.atherosclerosis, the leading cause of cardiovascular disease (cvd), is driven by inflammation. increasing evidence suggests that toll-like receptors (tlrs) are key orchestrators of the atherosclerotic disease process. interestingly, a distinct picture is being revealed for individual receptors in atherosclerosis. tlrs exhibit a complex nature enabling the detection of multiple motifs named danger-associated molecular patterns (damps) and pathogen-associated molecular patterns (pamps). activation ...201323880853
development of leptospira in vitro potency assays: eu/industry experience and perspectives.nobivac® lepto (msd animal health) is a non-adjuvanted canine leptospirosis vaccine containing inactivated whole cells of leptospira interrogans serogroup canicola serovar portlandvere and l. interrogans serogroup icterohaemorrhagiae serovar copenhageni. the current standard in vivo potency test is a hamster challenge test associated with major drawbacks such as animal suffering and poor reproducibility. here, the quantification of antigenic mass by elisa as a new in vitro potency test is descri ...201323867758
bba70 of borrelia burgdorferi is a novel plasminogen-binding protein.the lyme disease spirochete borrelia burgdorferi lacks endogenous, surface-exposed proteases. in order to efficiently disseminate throughout the host and penetrate tissue barriers, borreliae rely on recruitment of host proteases, such as plasmin(ogen). here we report the identification of a novel plasminogen-binding protein, bba70. binding of plasminogen is dose-dependent and is affected by ionic strength. the bba70-plasminogen interaction is mediated by lysine residues, primarily located in a p ...201323861404
monocyte human leukocyte antigen-dr expression-a tool to distinguish intestinal bacterial infections from inflammatory bowel disease?we sought to determine the quantitative expression of human leukocyte antigen-dr (hla-dr) on monocytes in patients with acute intestinal bacterial infections and inflammatory bowel disease (ibd).201323860582
expansion of the in vitro assay for leptospira potency testing to other serovars: case study with leptospira hardjo.evaluation of leptospiral vaccines for potency against leptospira interrogans serovars pomona, icterohaemorrhagiae, canicola, and grippotyphosa is accomplished using the hamster potency test method described in 9 cfr 113.101-104. applicability of this method to evaluation of bacterins developed for immunization against infection with l. interrogans serovar hardjo or leptospira borgpetersenii serovar hardjo is complicated by several issues. information from research on target host animal efficacy ...201323838569
ionic imbalance and lack of effect of adjuvant treatment with methylene blue in the hamster model of leptospirosis.leptospirosis in humans usually involves hypokalaemia and hypomagnesaemia and the putative mechanism underlying such ionic imbalances may be related to nitric oxide (no) production. we previously demonstrated the correlation between serum levels of no and the severity of renal disease in patients with severe leptospirosis. methylene blue inhibits soluble guanylyl cyclase (downstream of the action of any no synthase isoforms) and was recently reported to have beneficial effects on clinical and ex ...201323827990
ecology of leptospira interrogans in norway rats (rattus norvegicus) in an inner-city neighborhood of vancouver, canada.leptospira interrogans is a bacterial zoonosis with a worldwide distribution for which rats (rattus spp.) are the primary reservoir in urban settings. in order to assess, monitor, and mitigate the risk to humans, it is important to understand the ecology of this pathogen in rats. the objective of this study was to characterize the ecology of l. interrogans in norway rats (rattus norvegicus) in an impoverished inner-city neighborhood of vancouver, canada.201323818996
automated target segmentation and real space fast alignment methods for high-throughput classification and averaging of crowded cryo-electron subtomograms.cryo-electron tomography allows the imaging of macromolecular complexes in near living conditions. to enhance the nominal resolution of a structure it is necessary to align and average individual subtomograms each containing identical complexes. however, if the sample of complexes is heterogeneous, it is necessary to first classify subtomograms into groups of identical complexes. this task becomes challenging when tomograms contain mixtures of unknown complexes extracted from a crowded environme ...201323812994
leptospirosis in fox squirrels (sciurus niger) of larimer county, colorado, usa.leptospirosis is a zoonotic disease caused by the bacterium leptospira interrogans. the organism is typically maintained within a geographic region by colonizing renal tubules of carrier animals and shed into the environment in urine. we assessed whether l. interrogans was present in fox squirrels (sciurus niger) in larimer county, colorado, usa, and whether it is associated with disease. twenty-two squirrels were trapped from 29 november 2011 to 15 december 2011 for use in an unrelated study. t ...201323778614
characterization of streptococcal platelet-activating factor acetylhydrolase variants that are involved in innate immune evasion.human pathogen group a streptococcus (gas) has developed mechanisms to subvert innate immunity. we recently reported that the secreted esterase produced by serotype m1 gas (sse(m1)) reduces neutrophil recruitment by targeting platelet-activating factor (paf). sse(m1) and sse produced by serotype m28 gas (sse(m28)) have a 37% sequence difference. this study aims at determining whether sse(m28) is also a paf acetylhydrolase and participates in innate immune evasion. we also examined whether sse ev ...201323774595
scrub typhus with sepsis and acute respiratory distress syndrome.scrub typhus is a major infectious threat in the asia-pacific region. we report an unusual case of scrub typhus in a patient in singapore who presented with sepsis and acute respiratory distress syndrome but lacked the pathognomonic eschar. the patient recovered after appropriate diagnosis and doxycycline treatment. rickettsial diseases should be included in the differential diagnosis of febrile illnesses in regions where the diseases are endemic, and absence of eschar should not be the criterio ...201323761149
a call to order at the spirochaetal host-pathogen interface.as the lyme disease spirochaete borrelia burgdorferi shuttles back and forth between arthropod vector and vertebrate host, it encounters vastly different and hostile environments. major mechanisms contributing to the success of this pathogen throughout this complex transmission cycle are phase and antigenic variation of abundant and serotype-defining surface lipoproteins. these peripherally membrane-anchored virulence factors mediate niche-specific interactions with vector/host factors and prote ...201323750784
serosurvey of dogs for human, livestock, and wildlife pathogens, uganda. 201323750507
cell extract-containing medium for culture of intracellular fastidious bacteria.the culture of fastidious microorganisms is a critical step in infectious disease studies. as a proof-of-concept experiment, we evaluated an empirical medium containing eukaryotic cell extracts for its ability to support the growth of coxiella burnetii. here, we demonstrate the exponential growth of several bacterial strains, including the c. burnetii nine mile phase i and phase ii strains, and c. burnetii isolates from humans and animals. low-oxygen-tension conditions and the presence of small ...201323740722
haemoglobin and red cell counts in leptospirosis patients infected with different serovars.the aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars.201323740067
a review of pig pathology in tanzania.the approximately 1.58 million pigs in tanzania represent 3.7% of the national population of quadruped meat-producing animals. pigs are kept mainly by small producers who own 99.5% of the national stock in units that average 3.04 animals (range 2-48). government policy has had little practical application. african swine fever, foot-and-mouth disease and cysticercosis are important diseases. the first two are notifiable diseases under tanzania legislation; the last has widespread distribution and ...201323733144
development of an enzyme-linked immunosorbent assay using a recombinant liga fragment comprising repeat domains 4 to 7.5 as an antigen for diagnosis of equine leptospirosis.leptospira immunoglobulin (ig)-like (lig) proteins are a novel family of surface-associated proteins in which the n-terminal 630 amino acids are conserved. in this study, we truncated the liga conserved region into 7 fragments comprising the 1st to 3rd (ligacon1-3), 4th to 7.5th (ligacon4-7.5), 4th (ligacon4), 4.5th to 5.5th (ligacon4.5-5.5), 5.5th to 6.5th (ligacon5.5-6.5), 4th to 5th (ligacon4-5), and 6th to 7.5th (ligacon6-7.5) repeat domains. all 7 recombinant lig proteins were screened usin ...201323720368
precipitation of iron on the surface of leptospira interrogans is associated with mutation of the stress response metalloprotease htpx.high concentrations of free metal ions in the environment can be detrimental to bacterial survival. however, bacteria utilize strategies, including the activation of stress response pathways and immobilizing chemical elements on their surface, to limit this toxicity. in this study, we characterized la4131, the htpx-like m48 metalloprotease from leptospira interrogans, with a putative role in bacterial stress response and membrane homeostasis. growth of the la4131 transposon mutant strain (l522) ...201323709510
acyltransferases in bacteria.long-chain-length hydrophobic acyl residues play a vital role in a multitude of essential biological structures and processes. they build the inner hydrophobic layers of biological membranes, are converted to intracellular storage compounds, and are used to modify protein properties or function as membrane anchors, to name only a few functions. acyl thioesters are transferred by acyltransferases or transacylases to a variety of different substrates or are polymerized to lipophilic storage compou ...201323699259
leptospiral outer membrane protein lipl41 is not essential for acute leptospirosis but requires a small chaperone protein, lep, for stable expression.leptospirosis is a worldwide zoonosis caused by pathogenic leptospira spp., but knowledge of leptospiral pathogenesis remains limited. however, the development of mutagenesis systems has allowed the investigation of putative virulence factors and their involvement in leptospirosis. lipl41 is the third most abundant lipoprotein found in the outer membranes of pathogenic leptospires and has been considered a putative virulence factor. lipl41 is encoded on the large chromosome 28 bp upstream of a s ...201323690405
the mtb proteome library: a resource of assays to quantify the complete proteome of mycobacterium tuberculosis.research advancing our understanding of mycobacterium tuberculosis (mtb) biology and complex host-mtb interactions requires consistent and precise quantitative measurements of mtb proteins. we describe the generation and validation of a compendium of assays to quantify 97% of the 4,012 annotated mtb proteins by the targeted mass spectrometric method selected reaction monitoring (srm). furthermore, we estimate the absolute abundance for 55% of all mtb proteins, revealing a dynamic range within th ...201323684311
detection of lipl32-specific igm by elisa in sera of patients with a clinical diagnosis of leptospirosis.successful treatment of leptospirosis is heavily dependent on early diagnosis and prompt initiation of antibiotic therapy. an elisa test to detect specific igm antibodies against lipl32 for early diagnosis of leptospirosis is described and evaluated here. one thousand one hundred and eighty sera from clinically suspected leptospirosis cases were enrolled together with 109 healthy volunteers selected from an endemic area between october 2007 and january 2010. patients were categorized based on th ...201323683367
chemogenomics profiling of drug targets of peptidoglycan biosynthesis pathway in leptospira interrogans by virtual screening approaches.leptospirosis is a worldwide zoonosis of global concern caused by leptospira interrogans. the availability of ligand libraries has facilitated the search for novel drug targets using chemogenomics approaches, compared with the traditional method of drug discovery, which is time consuming and yields few leads with little intracellular information for guiding target selection. recent subtractive genomics studies have revealed the putative drug targets in peptidoglycan biosynthesis pathways in lept ...201323676922
incidence of leptospirosis infection in the east zone of sao paulo city, brazil.leptospirosis is a zoonosis which is spread through contamined running water. this contaminations is seriously affected by the flooding which occurs in the area surrounding the aricanduva river. the transmission of the disease results mainly from the contact of water with soil contaminated by the urine of infected animals. we aimed to conduct an epidemiological survey on leptospirosis cases in sao paulo east zone area.201323672682
leptospira interrogans at the human-wildlife interface in northern botswana: a newly identified public health threat.leptospirosis is the most widespread zoonosis in the world. in northern botswana, humans live in close proximity to a diversity of wildlife and peridomestic rodents and may be exposed to a variety of zoonotic pathogens. little is known regarding the occurrence and epidemiology of l. interrogans in africa despite the recognized global importance of this zoonotic disease and the threat it poses to public health. in botswana, banded mongooses (mungos mungo) live in close proximity to humans across ...201423672285
aggregate-reactivation activity of the molecular chaperone clpb from ehrlichia chaffeensis.rickettsiale diseases, including human monocytic ehrlichiosis caused by ehrlichia chaffeensis, are the second leading cause of the tick-borne infections in the usa and a growing health concern. little is known about how e. chaffeensis survives the host-induced stress in vertebrate and tick hosts. a molecular chaperone clpb from several microorganisms has been reported to reactivate aggregated proteins in cooperation with the co-chaperones dnak/dnaj/grpe (kje). in this study, we performed the fir ...201323667479
evaluation of the elastinolytic activity and protective effect of leptallo i, a protein composed by metalloprotease and fa5/8c domains, from leptospira interrogans copenhageni.leptospirosis is a re-emergent zoonosis, caused by pathogenic spirochetes from the genus lepstospira. to date, there is no protein described to be involved in leptospiral hemorrhagic manifestations, although several proteases have been reported for other bacterial infections. in this study we identified 12 putative metalloproteases from the genome of leptospira interrogans, and characterized for the first time a putative metalloprotease, here named leptallo i, as a potential zn(2+) dependent gly ...201323665291
a chimeric udp-glucose pyrophosphorylase produced by protein engineering exhibits sensitivity to allosteric regulators.in bacteria, glycogen or oligosaccharide accumulation involves glucose-1-phosphate partitioning into either adp-glucose (adp-glc) or udp-glc. their respective synthesis is catalyzed by allosterically regulated adp-glc pyrophosphorylase (ec 2.7.7.27, adp-glc ppase) or unregulated udp-glc ppase (ec 2.7.7.9). in this work, we characterized the udp-glc ppase from streptococcus mutans. in addition, we constructed a chimeric protein by cutting the c-terminal domain of the adp-glc ppase from escherichi ...201323648478
climate variability and outbreaks of infectious diseases in europe.several studies provide evidence of a link between vector-borne disease outbreaks and el niño driven climate anomalies. less investigated are the effects of the north atlantic oscillation (nao). here, we test its impact on outbreak occurrences of 13 infectious diseases over europe during the last fifty years, controlling for potential bias due to increased surveillance and detection. nao variation statistically influenced the outbreak occurrence of eleven of the infectious diseases. seven diseas ...201323639950
sex bias in infectious disease epidemiology: patterns and processes.infectious disease incidence is often male-biased. two main hypotheses have been proposed to explain this observation. the physiological hypothesis (ph) emphasizes differences in sex hormones and genetic architecture, while the behavioral hypothesis (bh) stresses gender-related differences in exposure. surprisingly, the population-level predictions of these hypotheses are yet to be thoroughly tested in humans.201323638062
rats, cities, people, and pathogens: a systematic review and narrative synthesis of literature regarding the ecology of rat-associated zoonoses in urban centers.urban norway and black rats (rattus norvegicus and rattus rattus) are the source of a number of pathogens responsible for significant human morbidity and mortality in cities around the world. these pathogens include zoonotic bacteria (leptospira interrogans, yersina pestis, rickettsia typhi, bartonella spp., streptobacillus moniliformis), viruses (seoul hantavirus), and parasites (angiostrongylus cantonensis). a more complete understanding of the ecology of these pathogens in people and rats is ...201323590323
a ubiquitous method for street scale spatial data collection and analysis in challenging urban environments: mapping health risks using spatial video in haiti.fine-scale and longitudinal geospatial analysis of health risks in challenging urban areas is often limited by the lack of other spatial layers even if case data are available. underlying population counts, residential context, and associated causative factors such as standing water or trash locations are often missing unless collected through logistically difficult, and often expensive, surveys. the lack of spatial context also hinders the interpretation of results and designing intervention st ...201323587358
[prokaryotic expression of leptospira interrogans groel gene and immunoprotection of its products in hamsters].to construct a prokaryotic expression system of groel gene of leptospira interrogans serogroup icterohaemorrhagia serovar lai strain lai, and to determine the immunoprotective effect of recombinant groel protein (rgroel) in lvg hamsters.201323585002
[expression changes of major outer membrane protein antigens in leptospira interrogans during infection and its mechanism].to determine expression changes of major outer membrane protein(omp) antigens of leptospira interrogans serogroup icterohaemorrhagiae serovar lai strain lai during infection of human macrophages and its mechanism.201323585001
a survey of zoonotic diseases in trade cattle slaughtered at tanga city abattoir: a cause of public health concern.to estimate the prevalence of hydatidosis, cysticercosis, tuberculosis, leptospirosis, brucellosis and toxoplasmosis in slaughtered bovine stock (aged ±3 years) at tanga city abattoir, tanzania.201223569835
detection of leptospiral antibodies by microscopic agglutination test in north-east of iran.to detect leptospiral antibodies by microscopic agglutination test (mat) in north-east of iran.201123569764
the htra protease of borrelia burgdorferi degrades outer membrane protein bmpd and chemotaxis phosphatase chex.borrelia burgdorferi, the spirochaetal agent of lyme disease, codes for a single htra protein, htrabb (bb0104) that is homologous to degp of escherichia coli (41% amino acid identity). htrabb shows physical and biochemical similarities to degp in that it has the trimer as its fundamental unit and can degrade casein via its catalytic serine. recombinant htrabb exhibits proteolytic activity in vitro, while a mutant (htrabbs198a) does not. however, htrabb and degp have some important differences as ...201323565798
detection of reactive canines to leptospira in campeche city, mexico.leptospira reactivity in stray and household dogs in campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. the survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. nine leptospira interrogans serovars were tested by the microagglutination test. reactivity was 21.3 % (69/323), 17.2 % corresponded to household dogs and 26.7 % to stray dogs. leptospira canicola (29 %), leptospira hardjo (22.58 %), and leptospira ic ...201323560786
multiple single-cell genomes provide insight into functions of uncultured deltaproteobacteria in the human oral cavity.despite a long history of investigation, many bacteria associated with the human oral cavity have yet to be cultured. studies that correlate the presence or abundance of uncultured species with oral health or disease highlight the importance of these community members. thus, we sequenced several single-cell genomic amplicons from desulfobulbus and desulfovibrio (class deltaproteobacteria) to better understand their function within the human oral community and their association with periodontitis ...201323555659
a gene transfer agent and a dynamic repertoire of secretion systems hold the keys to the explosive radiation of the emerging pathogen bartonella.gene transfer agents (gtas) randomly transfer short fragments of a bacterial genome. a novel putative gta was recently discovered in the mouse-infecting bacterium bartonella grahamii. although gtas are widespread in phylogenetically diverse bacteria, their role in evolution is largely unknown. here, we present a comparative analysis of 16 bartonella genomes ranging from 1.4 to 2.6 mb in size, including six novel genomes from bartonella isolated from a cow, two moose, two dogs, and a kangaroo. a ...201323555299
in vitro assessment of functional properties of lactic acid bacteria isolated from faecal microbiota of healthy dogs for potential use as probiotics.lactic acid bacteria were isolated and identified in the faeces of chinese crested and yorkshire terrier pups and their probiotic features were investigated in vitro. thirty seven isolates were identified as lactobacillus or enterococcus. out of these isolates, 31 were lactic acid bacteria (lab) and belonged to the species lactobacillus reuteri (16/37; 43.3%), lactobacillus animalis (7/37; 18.9%), lactobacillus acidophilus (3/37; 8.1%), lactobacillus sanfranciscensis (2/37; 5.4%), lactobacillus ...201323538205
leptospirosis risk increases with changes in species composition of rat populations.rats are major reservoirs of leptospirosis and considered as a main threat to biodiversity. a recent introduction of rattus rattus to the island of futuna (western polynesia) provided the opportunity to test if a possible change in species composition of rat populations would increase the risk of leptospirosis to humans. we trapped rodents on wallis and futuna and assessed leptospira carriage in 357 rodents (rattus norvegicus, r. rattus, rattus exulans, and mus domesticus) from 2008 to 2012. whi ...201323535996
a case of mixed infections in a patient presenting with acute febrile illness in the tropics.concurrent infections with more than one etiological agent can result in an illness with overlapping symptoms, resulting in a situation where the diagnosis and management of such a patient could be challenging. we report a case of vivax malaria in a patient who was also serologically positive for leptospirosis and dengue.201323533853
structure and activity of the flagellar rotor protein fliy: a member of the chec phosphatase family.fliy is a flagellar rotor protein of the chec phosphatase family.201323532838
toll-like receptors as therapeutic targets for autoimmune connective tissue diseases.autoimmune connective tissue diseases (actds) are a family of consistent systemic autoimmune inflammatory disorders, including systemic lupus erythematosus (sle), rheumatoid arthritis (ra), systemic sclerosis (ssc) and sjögren's syndrome (ss). il-1r-like receptors (tlrs) are located on various cellular membranes and sense exogenous and endogenous danger-associated molecular patterns (damps) and pathogen-associated molecular patterns (pamps), playing a critical role in innate immune responses. du ...201323531543
p53 signalling controls cell cycle arrest and caspase-independent apoptosis in macrophages infected with pathogenic leptospira species.pathogenic leptospira species, the causative agents of leptospirosis, have been shown to induce macrophage apoptosis through caspase-independent, mitochondrion-related apoptosis inducing factor (aif) and endonuclease g (endog), but the signalling pathway leading to aif/endog-based macrophage apoptosis remains unknown. here we show that infection of leptospira interrogans caused a rapid increase in reactive oxygen species (ros), dna damage, and intranuclear foci of 53bp1 and phosphorylation of h2 ...201323521874
a prime-boost strategy using the novel vaccine candidate, lema, protects hamsters against leptospirosis.toward developing an effective vaccine capable of conferring heterologous protection, the putative lipoprotein lema, which presents an m3 epitope similar to that of listeria, was evaluated as a vaccine candidate in the hamster model of leptospirosis. lema is conserved (>70% pairwise identity) among the pathogenic leptospira spp., indicating its potential in stimulating a cross-protective immune response. using different vaccination strategies, including prime-boost, dna vaccine, and a subunit pr ...201323515012
evolutionary history of the plant pathogenic bacterium xanthomonas axonopodis.deciphering mechanisms shaping bacterial diversity should help to build tools to predict the emergence of infectious diseases. xanthomonads are plant pathogenic bacteria found worldwide. xanthomonas axonopodis is a genetically heterogeneous species clustering, into six groups, strains that are collectively pathogenic on a large number of plants. however, each strain displays a narrow host range. we address the question of the nature of the evolutionary processes--geographical and ecological spec ...201323505513
essential calcium-binding cluster of leptospira lipl32 protein for inflammatory responses through the toll-like receptor 2 pathway.leptospirosis is the most widespread zoonosis caused by the pathogenic leptospira worldwide. lipl32, a 32-kda lipoprotein, is the most abundant protein on the outer membrane of leptospira and has an atypical poly(asp) motif ((161)dddddgdd(168)). the x-ray crystallographic structure of lipl32 revealed that the calcium-binding cluster of lipl32 includes several essential residues asp(132), thr(133), asp(164), asp(165), and tyr(178). the goals of this study were to determine possible roles of the c ...201323486465
a conserved region of leptospiral immunoglobulin-like a and b proteins as a dna vaccine elicits a prophylactic immune response against leptospirosis.the leptospiral immunoglobulin-like (lig) proteins liga and ligb possess immunoglobulin-like domains with 90-amino-acid repeats and are adhesion molecules involved in pathogenicity. they are conserved in pathogenic leptospira spp. and thus are of interest for use as serodiagnostic antigens and in recombinant vaccine formulations. the n-terminal amino acid sequences of the liga and ligb proteins are identical, but the c-terminal sequences vary. in this study, we evaluated the protective potential ...201323486420
interaction of leptospira interrogans with human proteolytic systems enhances dissemination through endothelial cells and protease levels.we have recently reported the ability of leptospira to capture plasminogen (plg) and generate plasmin (pla) bound on the microbial surface in the presence of exogenous activators. in this work, we examined the effects of leptospiral plg binding for active penetration through the endothelial cell barrier and activation. the results indicate that leptospires with plg association or pla activation have enhanced migration activity through human umbilical vein endothelial cell (huvec) monolayers comp ...201323478319
development of immunochromatography-based methods for detection of leptospiral lipopolysaccharide antigen in urine.leptospirosis is an infectious disease caused by the spirochete bacteria leptospira spp. and is commonly found throughout the world. diagnosis of leptospirosis performed by culture and microscopic agglutination tests is laborious and time-consuming. therefore, we aimed to develop a novel immunochromatography (icg)-based method for detecting leptospira antigen in the urine of patients and animals. we used the 1h6 monoclonal antibody (mab), which is specific to the lipopolysaccharide (lps) that is ...201323467776
protein analysis by shotgun/bottom-up proteomics. 201323438204
molecular characterization of virulent leptospira interrogans serogroup icterohaemorrhagiae isolated from cavia aperea.leptospirosis is a worldwide zoonotic infection caused by pathogenic leptospira. synanthropic rodents are recognized carriers of leptospires; however, the role of wild rodents in the epidemiology of the disease is still incipient. in this work, we describe leptospira strain isolated from cavia aperea (brazilian guinea pig). the isolated strain was characterized by partial rpob gene sequencing, variable-number tandem-repeats and histopathological analysis. the strain was identified as leptospira ...201323435256
[preservation for vaccinal strains of leptospira at liquid nitrogen].leptospira interrogans strains of cuban vaccine vax-spiral are preserved in fletcher's semi-solid medium, which guarantees the preservation of the cell viability for a few months.201323431625
leptospira interrogans survey by pcr in wild rodents coming from different urban areas of palermo, italy.dna extracted from the kidneys of rodents captured in different urban areas of palermo, italy, had been analysed for the presence of pathogenic l. interrogans sensu latu dna. pcr analysis had shown that in rodents captured close to green areas and small river up to 40 % animals give positive pcr results. not many cases of human leptospirosis are reported in sicilian island in which hot season is usually dry. but considering climate change toward subtropical aspect in sicily, with hot humid summe ...201323427420
asymptomatic and chronic carriage of leptospira interrogans serovar pomona in california sea lions (zalophus californianus).since 1970, periodic outbreaks of leptospirosis, caused by pathogenic spirochetes in the genus leptospira, have caused morbidity and mortality of california sea lions (zalophus californianus) along the pacific coast of north america. yearly seasonal epizootics of varying magnitude occur between the months of july and december, with major epizootics occurring every 3-5 years. genetic and serological data suggest that leptospira interrogans serovar pomona is the infecting serovar and is enzootic i ...201323419822
the origin of 8-amino-3,8-dideoxy-d-manno-octulosonic acid (kdo8n) in the lipopolysaccharide of shewanella oneidensis.lipopolysaccharide (lps; endotoxin) is an essential component of the outer monolayer of nearly all gram-negative bacteria. lps is composed of a hydrophobic anchor, known as lipid a, an inner core oligosaccharide, and a repeating o-antigen polysaccharide. in nearly all species, the first sugar bridging the hydrophobic lipid a and the polysaccharide domain is 3-deoxy-d-manno-octulosonic acid (kdo), and thus it is critically important for lps biosynthesis. modifications to lipid a have been shown t ...201323413030
crystallographic study to determine the substrate specificity of an l-serine-acetylating enzyme found in the d-cycloserine biosynthetic pathway.dcse, one of the enzymes found in the d-cycloserine biosynthetic pathway, displays a high sequence homology to l-homoserine o-acetyltransferase (hat), but it prefers l-serine over l-homoserine as the substrate. to clarify the substrate specificity, in the present study we determined the crystal structure of dcse at a 1.81-å resolution, showing that the overall structure of dcse is similar to that of hat, whereas a turn region to form an oxyanion hole is obviously different between dcse and hat: ...201323396912
para-(benzoyl)-phenylalanine as a potential inhibitor against lpxc of leptospira spp.: homology modeling, docking, and molecular dynamics study.leptospira interrogans, a gram-negative bacterial pathogen is the main cause of human leptospirosis. lipid a is a highly immunoreactive endotoxic center of lipopolysaccharide (lps) that anchors lps into the outer membrane of leptospira. discovery of compounds inhibiting lipid-a biosynthetic pathway would be promising for dissolving the structural integrity of membrane leading to cell lysis and death of leptospira. lpxc, a unique enzyme of lipid-a biosynthetic pathway was identified as common dru ...201423383626
importance of uncharged polar residues and proline in the proximal two-thirds (pro107-ser128) of the highly conserved region of mouse ileal na+-dependent bile acid transporter, slc10a2, in transport activity and cellular expression.slc10a2-mediated reabsorption of bile acids at the distal end of the ileum is the first step in enterohepatic circulation. because bile acids act not only as detergents but also as signaling molecules in lipid metabolism and energy production, slc10a2 is important as the key transporter for understanding the in vivo kinetics of bile acids. slc10a family members and the homologous genes of various species share a highly conserved region corresponding to gly104-pro142 of slc10a2. the functional im ...201323374508
pathogenic and saprophytic leptospira species in water and soils from selected urban sites in peninsular malaysia.leptospira species were studied in water and soils from selected urban sites in malaysia. a total of 151 water (n=121) and soil (n=30) samples were collected from 12 recreational lakes and wet markets. all samples were filtered and inoculated into semi-solid ellinghausen and mccullough modified by johnson and harris (emjh) media supplemented with additional 5-fluorouracil. the cultures were then incubated at 30°c and observed under a dark field microscope with intervals of 10 days. a pcr assay t ...201323363618
isolation and molecular characterization of leptospira interrogans and leptospira borgpetersenii isolates from the urban rat populations of kuala lumpur, malaysia.rats are considered the principal maintenance hosts of leptospira. the objectives of this study were isolation and identification of leptospira serovars circulating among urban rat populations in kuala lumpur. three hundred urban rats (73% rattus rattus and 27% r. norvegicus) from three different sites were trapped. twenty cultures were positive for leptospira using dark-field microscopy. r. rattus was the dominant carrier (70%). polymerase chain reaction (pcr) confirmed that all isolates were p ...201323358635
pancreatitis and myocarditis followed by pulmonary hemorrhage, a rare presentation of leptospirosis- a case report and literature survey.leptospirosis is a potentially fatal disease which can cause multi-organ dysfunction. it can rarely present as acute pancreatitis. this is the first ever report of leptospirosis presenting with acute pancreatitis and myocarditis followed by diffuse pulmonary hemorrhages to the best of our knowledge.201323347428
the gain and loss of chromosomal integron systems in the treponema species.integron systems are now recognized as important agents of bacterial evolution and are prevalent in most environments. one of the human pathogens known to harbor chromosomal integrons, the treponema spirochetes are the only clade among spirochete species found to carry integrons. with the recent release of many new treponema genomes, we were able to study the distribution of chromosomal integrons in this genus.201323339550
seroprevalence of leptospirosis in dogs in urban harare and selected rural communities in zimbabwe.a cross-sectional study was conducted to investigate seroprevalence of canine leptospirosis in urban harare and five selected rural communities in zimbabwe and to assess public awareness of the disease. sera from randomly selected dogs were tested for antibodies to the serovars canicola, grippotyphosa, icterohaemorrhagiae and pomona of leptospira interrogans using an enzyme-linked immunosorbent assay. clinical chemistry was performed on all seropositive and selected seronegative sera to screen f ...201223327324
solution structure of the big domain from streptococcus pneumoniae reveals a novel ca2+-binding module.streptococcus pneumoniae is a pathogen causing acute respiratory infection, otitis media and some other severe diseases in human. in this study, the solution structure of a bacterial immunoglobulin-like (big) domain from a putative s. pneumoniae surface protein sp0498 was determined by nmr spectroscopy. sp0498 big domain adopts an eight-β-strand barrel-like fold, which is different in some aspects from the two-sheet sandwich-like fold of the canonical ig-like domains. intriguingly, we identified ...201323326635
risk factors and predictors of severe leptospirosis in new caledonia.leptospirosis is a major public health concern in new caledonia (nc) and in other tropical countries. severe manifestations of the disease are estimated to occur in 5-15% of all human infections worldwide and factors associated with these forms are poorly understood. our objectives were to identify risk factors and predictors of severe forms of leptospirosis in adults.201323326614
lipl32 is a subsurface lipoprotein of leptospira interrogans: presentation of new data and reevaluation of previous studies.the agents of leptospirosis, a zoonosis with worldwide distribution, are pathogenic spirochetes belonging to the genus leptospira. the leptospiral life cycle involves transmission via fresh water and colonization of the renal tubules of their reservoir hosts. infection of accidental hosts, including humans, may result in life-threatening sequelae. bacterial outer membrane proteins (omps), particularly those with surface-exposed regions, play crucial roles in pathogen virulence mechanisms and ada ...201323323152
first isolation of leptospira interrogans from lycalopex griseus (south american gray fox) in argentina shows new mlva genotype.to identify carriers of leptospira spp. in argentina, wild animals were trapped in buenos aires province during three nights, capturing 12 didelphis albiventris (white-eared opossum), six chaetophractus villosus (big hairy armadillo), five lycalopex griseus (south american gray fox), and two conepatus chinga (molina's hog-nosed skunk). all were tested by microscopic agglutination test, and five (two gray foxes, two armadillos, and one skunk) were positive for leptospira interrogans serovars cani ...201323307384
in vivo gene expression and immunoreactivity of leptospira collagenase.pulmonary hemorrhage is an increasing cause of death of leptospirosis patients. bacterial collagenase has been shown to be involved in lung hemorrhage induced by various infectious agents. according to leptospira whole genome study, cola, a gene suggested to code for bacterial collagenase has been identified. we investigated cola gene expression in lung tissues of leptospira infected hamsters. golden syrian hamsters were injected intraperitoneally with leptospira interrogans serovar pyrogenes. t ...201323305770
immunoproteomics: the key to discovery of new vaccine antigens against bacterial respiratory infections.the increase in antibiotic resistance and the shortage of new antimicrobials to prevent difficult bacterial infections underlines the importance of prophylactic therapies to prevent infection by bacterial pathogens. vaccination has reduced the incidence of many serious diseases, including respiratory bacterial infections. however, there are many pathogens for which no vaccine is available and some vaccines are not effective among all age groups or among immunocompromised individuals. immunoprote ...201223305366
adhesin activity of leptospira interrogans lipoprotein identified by in vivo and in vitro shotgun phage display.leptospira interrogans causes leptospirosis, one of the most common zoonotic diseases in the world. this pathogenic spirochete is able to bind to extracellular matrix, to express virulent factors and to cause host death. until now, there is no effective human vaccine for the disease. shotgun phage display genomic libraries of l. interrogans were constructed and used for in vivo biopanning in hamsters and screened for ligands able to bind to llc-pk1 epithelial cells. in both panning procedures, c ...201323291183
effect of osmolarity and viscosity on the motility of pathogenic and saprophytic leptospira.the motility of bacteria is an important factor in their infectivity. in this study, the motility of leptospira, a member of the spirochete family that causes a zoonotic disease known as leptospirosis, was analyzed in different viscous or osmotic conditions. motility assays revealed that both pathogenic and saprophytic strains increase their swimming speeds with increasing viscosity. however, only pathogenic leptospira interrogans maintained vigorous motility near physiological osmotic condition ...201323278547
comparative seroprevalence of leptospira interrogans in colombian mammals along a climatic gradient.leptospirosis is a widespread zoonotic disease with well-established impacts on human health in tropical and subtropical regions. although leptospira spp. are known to readily infect many wildlife species, the understanding of interspecies and climatic variability in patterns of infection in neotropical mammals is limited. to improve the understanding of this interplay, 85 mammals representing 17 species were sampled from four colombian zoos along a climatic gradient. prevalence of the 21 primar ...201223272343
molecular and serological investigation of leptospira and leptospirosis in dogs in japan.canine leptospirosis, which is caused by infection with pathogenic leptospira species, occurs worldwide, but information regarding the causative leptospira serotypes and genotypes and their effects on virulence in dogs remains limited. monitoring acute leptospirosis in dogs as sentinels can also aid in estimating the risk of human leptospirosis, particularly when the disease is rare, as it currently is in japan. among 283 clinically suspected cases of leptospirosis diagnosed from august 2007 to ...201223264455
serosurveillance for livestock pathogens in free-ranging mule deer (odocoileus hemionus).routine disease surveillance has been conducted for decades in mule deer (odocoileus hemionus) in california for pathogens shared between wildlife and domestic ruminants that may have implications for the animal production industry and wildlife health. deer sampled from 1990 to 2007 (n = 2,619) were tested for exposure to six pathogens: bluetongue virus (btv), epizootic hemorrhagic disease virus (ehdv), bovine viral diarrhea virus (bvdv), leptospira spp., anaplasma spp. and brucella spp. we eval ...201223209790
leptospirosis outbreaks in nicaragua: identifying critical areas and exploring drivers for evidence-based planning.leptospirosis is an epidemic-prone zoonotic disease that occurs worldwide. in central america, leptospirosis outbreaks have been reported in almost all countries; nicaragua in particular has faced several outbreaks. the objective of this study was to stratify the risk and identify "critical areas" for leptospirosis outbreaks in nicaragua, and to perform an exploratory analysis of potential "drivers". this ecological study includes the entire country (153 municipalities). cases from 2004 to 2010 ...201223202822
identification of epitopes in leptospira borgpetersenii leucine-rich repeat proteins.leptospirosis is considered to be a re-emerging disease that has impacts on public health both globally and in and thailand. the leptospires outbreak in thailand during 1999 was largely due to the etiologic agent leptospira borgpetersenii serogroup sejroe. this had a related immunity profile in cows from thailand, which serovars tarassovi and sejroe were prevalent. development of a vaccine protecting against leptospiral infection in livestock has been considered. one family of proteins being tar ...201323201041
cluster of leptospirosis cases among military personnel in rio de janeiro, brazil.we report two cases of leptospirosis in military personnel in southeastern brazil. the cases were hospitalized following field training exercises, and presented with acute meningoencephalitis, respiratory illnesses, and skin rash. leptospira interrogans serovars icterohaemorrhagiae, hebdomadis, patoc, and cynopteri were identified in the cases by microscopic agglutination test and pcr.201323195639
structure determination of lpxa from the lipopolysaccharide-synthesis pathway of acinetobacter baumannii.acinetobacter baumannii is a gram-negative pathogenic bacterium which is resistant to most currently available antibiotics and that poses a significant health threat to hospital patients. lpxa is a key enzyme in the biosynthetic pathway of the lipopolysaccharides that are components of the bacterial outer membrane. it is a potential target for antibacterial agents that might be used to fight a. baumannii infections. this paper describes the structure determination of the apo form of lpxa in spac ...201223192027
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
evaluation of immunoprotective activity of six leptospiral proteins in the hamster model of leptospirosis.leptospirosis is a worldwide zoonosis caused by pathogenic leptospira. the whole-genome sequence of l. interrogans serovar copenhageni together with bioinformatics tools represent a great opportunity to search for novel antigen candidates that could be used as subunit vaccine against leptospirosis. we focused on six genes encoding for conserved hypothetical proteins predicted to be exported to the outer membrane. the genes were amplified by pcr from leptospira interrogans genomic dna and were cl ...201223173023
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