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a strange lupus-like malar rash with renal involvement: an angioimmunoblastic t-cell lymphoma - a case report.cutaneous malar rash and kidney involvement has not previously been reported as presenting symptoms of an angioimmunoblastic t-cell lymphoma (aitl). we report a case of a woman with erythematous rash. a pet-ct revealed a lymphadenopathy and splenomegaly. an inguinal lymph node biopsy showed an aitl. there was clinical improvement after prednisone.201425678974
identification of cell-binding adhesins of leptospira interrogans.leptospirosis is a globally distributed bacterial infectious disease caused by pathogenic members of the genus leptospira. infection can lead to illness ranging from mild and non-specific to severe, with jaundice, kidney and liver dysfunction, and widespread endothelial damage. the adhesion of pathogenic leptospira species (spp.), the causative agent of leptospirosis, to host tissue components is necessary for infection and pathogenesis. while it is well-established that extracellular matrix (ec ...201425275630
liver involvement in systemic infection.the liver is often involved in systemic infections, resulting in various types of abnormal liver function test results. in particular, hyperbilirubinemia in the range of 2-10 mg/dl is often seen in patients with sepsis, and several mechanisms for this phenomenon have been proposed. in this review, we summarize how the liver is involved in various systemic infections that are not considered to be primarily hepatotropic. in most patients with systemic infections, treatment for the invading microbe ...201425276279
evolution of the f0f1 atp synthase complex in light of the patchy distribution of different bioenergetic pathways across prokaryotes.bacteria and archaea are characterized by an amazing metabolic diversity, which allows them to persist in diverse and often extreme habitats. apart from oxygenic photosynthesis and oxidative phosphorylation, well-studied processes from chloroplasts and mitochondria of plants and animals, prokaryotes utilize various chemo- or lithotrophic modes, such as anoxygenic photosynthesis, iron oxidation and reduction, sulfate reduction, and methanogenesis. most bioenergetic pathways have a similar general ...201425188293
microbe-specific unconventional t cells induce human neutrophil differentiation into antigen cross-presenting cells.the early immune response to microbes is dominated by the recruitment of neutrophils whose primary function is to clear invading pathogens. however, there is emerging evidence that neutrophils play additional effector and regulatory roles. the present study demonstrates that human neutrophils assume ag cross-presenting functions and suggests a plausible scenario for the local generation of apc-like neutrophils through the mobilization of unconventional t cells in response to microbial metabolite ...201425165152
the cross-talk between spirochetal lipoproteins and immunity.spirochetal diseases such as syphilis, lyme disease, and leptospirosis are major threats to public health. however, the immunopathogenesis of these diseases has not been fully elucidated. spirochetes interact with the host through various structural components such as lipopolysaccharides (lps), surface lipoproteins, and glycolipids. although spirochetal antigens such as lps and glycolipids may contribute to the inflammatory response during spirochetal infections, spirochetes such as treponema pa ...201425071771
adult-onset still's disease presenting as myopericarditis.a 24-year-old man presented to the emergency department with fever, maculopapular rash, myalgia and polyarthralgia, thoracic pain and dry cough, which had been present for 24 h. at the time of observation he had high fever (39°c), maculopapular rash on the torso, arms and legs proximally, axillary adenopathies and pharyngitis. laboratorial data showed elevated inflammation markers (leukocytosis, c reactive protein of 44 mg/dl, erythrocyte sedimentation rate of 120 mm), elevated transaminases, la ...201424898998
a putative regulatory genetic locus modulates virulence in the pathogen leptospira interrogans.limited research has been conducted on the role of transcriptional regulators in relation to virulence in leptospira interrogans, the etiological agent of leptospirosis. here, we identify an l. interrogans locus that encodes a sensor protein, an anti-sigma factor antagonist, and two genes encoding proteins of unknown function. transposon insertion into the gene encoding the sensor protein led to dampened transcription of the other 3 genes in this locus. this lb139 insertion mutant (the lb139(-) ...201424686063
development of a recombinase polymerase amplification assay for the detection of pathogenic leptospira.detection of leptospires based on dna amplification techniques is essential for the early diagnosis of leptospirosis when anti-leptospira antibodies are below the detection limit of most serological tests. in middle and low income countries where leptospirosis is endemic, routine implementation of real-time pcr is financially and technically challenging due to the requirement of expensive thermocycler equipment. in this study we report the development and evaluation of a novel isothermal recombi ...201424814943
abstracts from the 37th annual meeting of the society of general internal medicine, 2014, san diego, ca, usa. 201424737224
molecular architecture of the bacterial flagellar motor in cells.the flagellum is one of the most sophisticated self-assembling molecular machines in bacteria. powered by the proton-motive force, the flagellum rapidly rotates in either a clockwise or counterclockwise direction, which ultimately controls bacterial motility and behavior. escherichia coli and salmonella enterica have served as important model systems for extensive genetic, biochemical, and structural analysis of the flagellum, providing unparalleled insights into its structure, function, and gen ...201424697492
a model system for studying the transcriptomic and physiological changes associated with mammalian host-adaptation by leptospira interrogans serovar copenhageni.leptospirosis, an emerging zoonotic disease with worldwide distribution, is caused by spirochetes belonging to the genus leptospira. more than 500,000 cases of severe leptospirosis are reported annually, with >10% of these being fatal. leptospires can survive for weeks in suitably moist conditions before encountering a new host. reservoir hosts, typically rodents, exhibit little to no signs of disease but shed large numbers of organisms in their urine. transmission occurs when mucosal surfaces o ...201424626166
b-cell-specific peptides of leptospira interrogans liga for diagnosis of patients with acute leptospirosis.leptospirosis is a reemerging infectious disease that is underdiagnosed and under-recognized due to low-sensitivity and cumbersome serological tests. rapid reliable alternative tests are needed for early diagnosis of the disease. considering the importance of the pathogenesis-associated leptospiral liga protein expressed in vivo, we have evaluated its application in the diagnosis of the acute form of leptospirosis. the c-terminal coding sequence of liga (liga-c) was cloned into pet15b and expres ...201424403522
identification of borrelia species after creation of an in-house maldi-tof ms database.lyme borreliosis (lb) is a multisystemic disease caused by borrelia burgdorferi sensu lato (sl) complex transmitted to humans by ixodes ticks. b. burgdorferi sl complex, currently comprising at least 19 genospecies, includes the main pathogenic species responsible for human disease in europe: b. burgdorferi sensu stricto (ss), b. afzelii, and b. garinii. in this study, for the first time, maldi-tof ms was applied to borrelia spp., supplementing the existing database, limited to the species b. bu ...201424533160
oral immunization with escherichia coli expressing a lipidated form of liga protects hamsters against challenge with leptospira interrogans serovar copenhageni.leptospirosis is a potentially fatal zoonosis transmitted by reservoir host animals that harbor leptospires in their renal tubules and shed the bacteria in their urine. leptospira interrogans serovar copenhageni transmitted from rattus norvegicus to humans is the most prevalent cause of urban leptospirosis. we examined l. interrogans liga, domains 7 to 13 (liga7-13), as an oral vaccine delivered by escherichia coli as a lipidated, membrane-associated protein. the efficacy of the vaccine was eval ...201424478102
the multifunctional role of the pallilysin-associated treponema pallidum protein, tp0750, in promoting fibrinolysis and extracellular matrix component degradation.the mechanisms that facilitate dissemination of the highly invasive spirochaete, treponema pallidum, are incompletely understood. previous studies showed the treponemal metalloprotease pallilysin (tp0751) possesses fibrin clot degradation capability, suggesting a role in treponemal dissemination. in the current study we report characterization of the functionally linked protein tp0750. structural modelling predicts tp0750 contains a von willebrand factor type a (vwfa) domain, a protein-protein i ...201424303899
pyruvate protects pathogenic spirochetes from h2o2 killing.pathogenic spirochetes cause clinically relevant diseases in humans and animals, such as lyme disease and leptospirosis. the causative agent of lyme disease, borrelia burgdorferi, and the causative agent of leptospirosis, leptospria interrogans, encounter reactive oxygen species (ros) during their enzootic cycles. this report demonstrated that physiologically relevant concentrations of pyruvate, a potent h2o2 scavenger, and provided passive protection to b. burgdorferi and l. interrogans against ...201424392147
association between footwear use and neglected tropical diseases: a systematic review and meta-analysis.the control of neglected tropical diseases (ntds) has primarily focused on preventive chemotherapy and case management. less attention has been placed on the role of ensuring access to adequate water, sanitation, and hygiene and personal preventive measures in reducing exposure to infection. our aim was to assess whether footwear use was associated with a lower risk of selected ntds.201425393620
viability of leptospira isolates from a human outbreak in thailand in various water types, ph, and temperature conditions.leptospira spp. isolated from patients during a multiyear outbreak in thailand were genotyped using multilocus sequence typing and a majority were identified as st34, especially in earlier years. we tested whether st34 isolates were better adapted to survive in various ph levels, temperatures, and water sources. motility and growth were monitored over a 12-week period. early year st34 isolates did not appear to have a significant fitness advantage over non-st34, however, this may have been becau ...201425200260
serological and molecular survey of leptospira spp. among cart horses from an endemic area of human leptospirosis in curitiba, southern brazil.cart horses are a re-emerging population employed to carry recyclable material in cities.201425351539
leptospirosis: the microscopic danger in paradise.leptospirosis is a zoonotic infection endemic in hawai'i. this review discusses the incidence of documented human cases in hawai'i and current recommendations for diagnosis, prevention, and treatment of leptospirosis.201425478298
proteomic features predict seroreactivity against leptospiral antigens in leptospirosis patients.with increasing efficiency, accuracy, and speed we can access complete genome sequences from thousands of infectious microorganisms; however, the ability to predict antigenic targets of the immune system based on amino acid sequence alone is still needed. here we use a leptospira interrogans microarray expressing 91% (3359) of all leptospiral predicted orfs (3667) and make an empirical accounting of all antibody reactive antigens recognized in sera from naturally infected humans; 191 antigens el ...201425358092
proteomic features predict seroreactivity against leptospiral antigens in leptospirosis patients.with increasing efficiency, accuracy, and speed we can access complete genome sequences from thousands of infectious microorganisms; however, the ability to predict antigenic targets of the immune system based on amino acid sequence alone is still needed. here we use a leptospira interrogans microarray expressing 91% (3359) of all leptospiral predicted orfs (3667) and make an empirical accounting of all antibody reactive antigens recognized in sera from naturally infected humans; 191 antigens el ...201425358092
decay-accelerating factor 1 deficiency exacerbates leptospiral-induced murine chronic nephritis and renal fibrosis.leptospirosis is a global zoonosis caused by pathogenic leptospira, which can colonize the proximal renal tubules and persist for long periods in the kidneys of infected hosts. here, we characterized the infection of c57bl/6j wild-type and daf1-/- mice, which have an enhanced host response, with a virulent leptospira interrogans strain at 14 days post-infection, its persistence in the kidney, and its link to kidney fibrosis at 90 days post-infection. we found that leptospira interrogans can indu ...201425032961
increasing incidence of canine leptospirosis in switzerland.a marked increase in canine leptospirosis was observed in switzerland over 10 years with a peak incidence of 28.1 diagnosed cases/100,000 dogs/year in the most affected canton. with 95% affected dogs living at altitudes <800 m, the disease presented a seasonal pattern associated with temperature (r2 0.73) and rainfall (r2 0.39), >90% cases being diagnosed between may and october. the increasing yearly incidence however was only weakly correlated with climatic data including number of summer (r2 ...201425032740
a questionnaire-based survey on the uptake and use of cattle vaccines in the uk.vaccination is a widely used strategy for disease control in cattle in the uk and abroad. however, there has been limited research describing the uptake and use of cattle vaccines on uk farms.201426392877
an ortholog of the leptospira interrogans lipoprotein lipl32 aids in the colonization of pseudoalteromonas tunicata to host surfaces.the bacterium pseudoalteromonas tunicata is a common surface colonizer of marine eukaryotes, including the macroalga ulva australis.genomic analysis of p. tunicata identified genes potentially involved in surface colonization, including genes with homology to bacterial virulence factors that mediate attachment. of particular interest is the presence of a gene, designated ptll32, encoding an ortholog to the leptospira lipoprotein lipl32, which has been shown to facilitate the interaction of lepto ...201425071736
strengthening public health laboratory capacity in thailand for international health regulations (ihr) (2005).thailand conducted a national laboratory assessment of core capacities related to the international health regulations (ihr) (2005), and thereby established a baseline to measure future progress. the assessment was limited to public laboratories found within the thai bureau of quality and safety of food, national institute of health and regional medical science centres.201426693144
comparing the different morphotypes of a fish pathogen--implications for key virulence factors in flavobacterium columnare.flavobacterium columnare (bacteroidetes) is the causative agent of columnaris disease in farmed freshwater fish around the world. the bacterium forms three colony morphotypes (rhizoid, rough and soft), but the differences of the morphotypes are poorly known. we studied the virulence of the morphotypes produced by f. columnare strain b067 in rainbow trout (onconrhynchus mykiss) and used high-resolution scanning electron microscopy to identify the fine structures of the cells grown in liquid and o ...201424964840
leptospirosis in vellore: a clinical and serological study.leptospirosis is a severe spirochetal zoonosis in the world. it is considered an occupational disease of persons engaged in agriculture, sewage works, forestry, and animal slaughtering. a study was conducted with an objective of assessing the seroprevalence of leptospirosis in and around vellore district, tamil nadu. the study was based on the signs and symptoms of the patients reporting fever in vellore municipal clinic (urban malarial scheme). blood samples were collected from 129 patients. an ...201425050124
'black sheep' that don't leave the double-stranded rna-binding domain fold.the canonical double-stranded rna (dsrna)-binding domain (dsrbd) is composed of an α1-β1-β2-β3-α2 secondary structure that folds in three dimensions to recognize dsrna. recently, structural and functional studies of divergent dsrbds revealed adaptations that include intra- and/or intermolecular protein interactions, sometimes in the absence of detectable dsrna-binding ability. we describe here how discrete dsrbd components can accommodate pronounced amino-acid sequence changes while maintaining ...201424954387
using peptideatlas, srmatlas, and passel: comprehensive resources for discovery and targeted proteomics.peptideatlas, srmatlas, and passel are web-accessible resources to support discovery and targeted proteomics research. peptideatlas is a multi-species compendium of shotgun proteomic data provided by the scientific community; srmatlas is a resource of high-quality, complete proteome srm assays generated in a consistent manner for the targeted identification and quantification of proteins; and passel is a repository that compiles and represents selected reaction monitoring data, all in an easy-to ...201424939129
approach to clinical syndrome of jaundice and encephalopathy in tropics.a large number of patients present with jaundice and encephalopathy in tropical country like india and acute liver failure is the usual cause. clinical presentation like alf is also a complication of many tropical infections, and these conditions may mimic alf but may have subtle differences from alf. moreover, what hepatologists see as acute liver failure in tropics is different from what is commonly described in western textbooks. paracetamol overdose, which is possibly the commonest cause of ...201426041951
approach to clinical syndrome of jaundice and encephalopathy in tropics.a large number of patients present with jaundice and encephalopathy in tropical country like india and acute liver failure is the usual cause. clinical presentation like alf is also a complication of many tropical infections, and these conditions may mimic alf but may have subtle differences from alf. moreover, what hepatologists see as acute liver failure in tropics is different from what is commonly described in western textbooks. paracetamol overdose, which is possibly the commonest cause of ...201426041951
modelling the efficiency of codon-trna interactions based on codon usage bias.the trna adaptation index (tai) is a widely used measure of the efficiency by which a coding sequence is recognized by the intra-cellular trna pool. this index includes among others weights that represent wobble interactions between codons and trna molecules. currently, these weights are based only on the gene expression in saccharomyces cerevisiae. however, the efficiencies of the different codon-trna interactions are expected to vary among different organisms. in this study, we suggest a new a ...201424906480
a cross sectional observational study to estimate herd level risk factors for leptospira spp. serovars in small holder dairy cattle farms in southern chile.the south of chile constitutes the main cattle milk producing area of the country. regarding leptospirosis control in chile, there is neither an official program nor an epidemiological characterization of smallholder dairy farms. this study was carried out to determine leptospira seroprevalence and to evaluate risk factors associated with seropositivity at herd level in smallholder bovine dairy herds in southern chile.a cross-sectional study was conducted, and a convenient sample of 1,537 appare ...201424906684
regional and temporal variations of leptospira seropositivity in dogs in the united states, 2000-2010.previous studies have reported a seasonal increased risk for leptospirosis, but there is no consistent seasonality reported across regions in the united states.201424597659
diagnostic efficacy of lsa63 antigen for human leptospirosis.timely diagnosis of leptospirosis is essential for early and effective treatment, for there are many differential diagnoses for it.. leptospiral researchers have an increasing interest in developing new serological methods with recombinant antigens to improve the leptospirosis diagnosis. several serological tests have been developed for the proper diagnosis of leptospirosis.201424829775
purification and biophysical characterization of the capa membrane protein ftt0807 from francisella tularensis.the capa gene (ftt0807) from francisella tularensis subsp. tularensis schu s4 encodes a 44.4 kda integral membrane protein composed of 403 amino acid residues that is part of an apparent operon that encodes at least two other membrane proteins, capb, and capc, which together play a critical role in the virulence and pathogenesis of this bacterium. the capa gene was overexpressed in escherichia coli as a c-terminal his6-tagged fusion with a folding reporter green fluorescent protein (frgfp). puri ...201424593131
loop-mediated isothermal amplification for rickettsia typhi (the causal agent of murine typhus): problems with diagnosis at the limit of detection.murine typhus is a flea-borne disease of worldwide distribution caused by rickettsia typhi. although treatment with tetracycline antibiotics is effective, treatment is often misguided or delayed due to diagnostic difficulties. as the gold standard immunofluorescence assay is imperfect, we aimed to develop and evaluate a loop-mediated isothermal amplification (lamp) assay. lamp assays have the potential to fulfill the who assured criteria (affordable, sensitive, specific, user friendly, robust an ...201424371248
detection of leptospira spp. in wildlife reservoir hosts in ontario through comparison of immunohistochemical and polymerase chain reaction genotyping methods.a total of 460 kidney samples from wildlife (beavers, coyotes, deer, foxes, opossums, otters, raccoons, skunks) were obtained from road-kill and hunter/trapper donations in ontario between january 2010 and november 2012. the objectives of the study were to detect leptospira spp. by immunohistochemistry and polymerase chain reaction (pcr), to map presence of leptospires in wildlife relative to livestock and human populations, and to characterize positive samples by sequencing and comparison to le ...201424587507
diagnosis of canine leptospirosis by a highly sensitive fret-pcr targeting the lig genes.canine leptospirosis is underdiagnosed due to its wide spectrum of clinical presentations and the lack of a rapid and sensitive test for the accurate diagnosis of acute and chronic infections. in this study, we developed a highly sensitive and specific fluorescence resonance energy transfer (fret)-pcr to detect common pathogenic leptospires in dogs, including leptospira interrogans serovars autumnalis, canicola, copenhageni (icterohaemorrhagiae serogroup) and pomona, and leptospira kirschneri se ...201424586833
haemophilus ducreyi hfq contributes to virulence gene regulation as cells enter stationary phase.to adapt to stresses encountered in stationary phase, gram-negative bacteria utilize the alternative sigma factor rpos. however, some species lack rpos; thus, it is unclear how stationary-phase adaptation is regulated in these organisms. here we defined the growth-phase-dependent transcriptomes of haemophilus ducreyi, which lacks an rpos homolog. compared to mid-log-phase organisms, cells harvested from the stationary phase upregulated genes encoding several virulence determinants and a homolog ...201424520065
genotypes of pathogenic leptospira spp isolated from rodents in argentina.leptospirosis is the most widespread zoonosis in the world and significant efforts have been made to determine and classify pathogenic leptospira strains. this zoonosis is maintained in nature through chronic renal infections of carrier animals, with rodents and other small mammals serving as the most important reservoirs. additionally, domestic animals, such as livestock and dogs, are significant sources of human infection. in this study, a multiple-locus variable-number tandem repeat analysis ...201424676656
sero-prevalence and risk factors for leptospirosis in abattoir workers in new zealand.leptospirosis is an important occupational disease in new zealand. the objectives of this study were to determine risk factors for sero-prevalence of leptospiral antibodies in abattoir workers. sera were collected from 567 abattoir workers and tested by microscopic agglutination for leptospira interrogans sv. pomona and leptospira borgpetersenii sv. hardjobovis. association between prevalence and risk factors were determined by species specific multivariable analysis. eleven percent of workers h ...201424503973
seroprevalence of leptospira hardjo in cattle and african buffalos in southwestern uganda.leptospirosis, caused by the spirochete bacterium leptospira spp. is a zoonosis, distributed worldwide and classified as an emerging infectious disease. fatal outcomes to leptospiral infection do occur and the disease can cause abortion and other reproductive problems in cattle, goats, and pigs. in humans the symptoms range from subclinical infection to acute febrile illness, pulmonary hemorrhage and renal failure. leptospirosis has never been officially reported to the world health organization ...201424323512
leptospirosis in pregnancy with pathological fetal cardiotocography changes.we report the case of a 33-year-old primigravida who presented at 37 weeks of gestation with symptoms suggestive of acute fatty liver of pregnancy, but was later diagnosed with leptospirosis (i.e. weil’s disease or syndrome) on serological testing. cardiotocography showed fetal distress, and an emergency caesarean section was performed. a healthy neonate with no evidence of congenital leptospirosis was delivered. the patient was treated with intravenous ceftriaxone and discharged well 13 days af ...201424712035
identification of a proton-chloride antiporter (eric) by himar1 transposon mutagenesis in lactobacillus reuteri and its role in histamine production.the gut microbiome may modulate intestinal immunity by luminal conversion of dietary amino acids to biologically active signals. the model probiotic organism lactobacillus reuteri atcc pta 6475 is indigenous to the human microbiome, and converts the amino acid l-histidine to the biogenic amine, histamine. histamine suppresses tumor necrosis factor (tnf) production by human myeloid cells and is a product of l-histidine decarboxylation, which is a proton-facilitated reaction. a transposon mutagene ...201424488273
role of 72 kda protein of leptospira interrogans as a diagnostic marker in acute leptospirosis.leptospirosis is a widespread zoonotic disease and a public health problem, particularly in tropical and subtropical countries. varied clinical manifestations of the disease frequently lead to misdiagnosis resulting in life-threatening multi-organ complications. therefore, early laboratory investigation using an appropriate diagnostic approach is crucial. in the present study, a potential protein marker was identified and evaluated for its usefulness in the serodiagnosis of acute leptospirosis.201424718408
tropical fevers: management guidelines.tropical fevers were defined as infections that are prevalent in, or are unique to tropical and subtropical regions. some of these occur throughout the year and some especially in rainy and post-rainy season. concerned about high prevalence and morbidity and mortality caused by these infections, and overlapping clinical presentations, difficulties in arriving at specific diagnoses and need for early empiric treatment, indian society of critical care medicine (isccm) constituted an expert committ ...201424678147
bacteria isolated from conspecific bite wounds in norway and black rats: implications for rat bite-associated infections in people.bites associated with wild and domestic norway and black rats (rattus norvegicus and rattus rattus) may have a variety of health consequences in people. bite-related infections are among the most significant of these consequences; however, there is little data on the infectious agents that can be transmitted from rats to people through biting. this is problematic because without an accurate understanding of bite-related infection risks, it is difficult for health professionals to evaluate the ad ...201424528094
factors associated with thrombocytopenia in severe leptospirosis (weil's disease).this study was conducted to investigate factors associated with thrombocytopenia in a large cohort of patients with leptospirosis in an endemic area.201424519201
high-resolution typing of leptospira interrogans strains by multispacer sequence typing.leptospirosis is a worldwide zoonosis which is responsible for the typical form of weil's disease. the epidemiological surveillance of the leptospira species agent is important for host prevalence control. although the genotyping methods have progressed, the identification of some serovars remains ambiguous. we investigated the multispacer sequence typing (mst) method for genotyping strains belonging to the species leptospira interrogans, which is the main agent of leptospirosis worldwide. a tot ...201424478489
carriage of clostridium difficile by wild urban norway rats (rattus norvegicus) and black rats (rattus rattus).clostridium difficile is an important cause of enteric infections in humans. recently, concerns have been raised regarding whether animals could be a source of c. difficile spores. although colonization has been identified in a number of domestic species, the ability of commensal pests to serve as a reservoir for c. difficile has not been well investigated. the objective of this study was to determine whether urban rats (rattus spp.) from vancouver, canada, carry c. difficile. clostridium diffic ...201424317079
comprehensive absolute quantification of the cytosolic proteome of bacillus subtilis by data independent, parallel fragmentation in liquid chromatography/mass spectrometry (lc/ms(e)).in the growing field of systems biology, the knowledge of protein concentrations is highly required to truly understand metabolic and adaptational networks within the cells. therefore we established a workflow relying on long chromatographic separation and mass spectrometric analysis by data independent, parallel fragmentation of all precursor ions at the same time (lc/ms(e)). by prevention of discrimination of co-eluting low and high abundant peptides a high average sequence coverage of 40% cou ...201424696501
leptospira interrogans binds to cadherins.leptospirosis, caused by pathogenic species of leptospira, is the most widespread zoonosis and has emerged as a major public health problem worldwide. the adhesion of pathogenic leptospira to host cells, and to extracellular matrix (ecm) components, is likely to be necessary for the ability of leptospires to penetrate, disseminate and persist in mammalian host tissues. previous work demonstrated that pathogenic l. interrogans binds to host cells more efficiently than to ecm. using two independen ...201424498454
leptospira interrogans induces fibrosis in the mouse kidney through inos-dependent, tlr- and nlr-independent signaling pathways.leptospira (l.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. rodents carry l. interrogans asymptomatically in their kidneys and excrete bacteria in the urine, contaminating the environment. humans get infected through skin contact and develop a mild or severe leptospirosis that may lead to renal failure and fibrosis. l. interrogans provoke an interstitial nephritis, but the induction of fibrosis caused by l. interrogans has not been studied in murine models. innate i ...201424498450
central cavity of fructose-1,6-bisphosphatase and the evolution of amp/fructose 2,6-bisphosphate synergism in eukaryotic organisms.the effects of amp and fructose 2,6-bisphosphate (fru-2,6-p2) on porcine fructose-1,6-bisphosphatase (pfbpase) and escherichia coli fbpase (efbpase) differ in three respects. amp/fru-2,6-p2 synergism in pfbpase is absent in efbpase. fru-2,6-p2 induces a 13° subunit pair rotation in pfbpase but no rotation in efbpase. hydrophilic side chains in efbpase occupy what otherwise would be a central aqueous cavity observed in pfbpase. explored here is the linkage of amp/fru-2,6-p2 synergism to the centr ...201424436333
serologic and urinary pcr survey of leptospirosis in healthy cats and in cats with kidney disease.although there is serologic evidence of exposure of cats to leptospira spp., clinical disease is rarely reported in cats.201424417764
human leptospirosis on reunion island: past and current burden.since 1953, leptospirosis has been recognized as a public health problem on reunion island. in 2004, was implemented a specific surveillance system that included systematic reporting and the realization of environmental investigations around hospitalized cases. here, we present the synthesis of historical data and the assessment of 9 years of leptospirosis surveillance. from 2004 to 2012, 414 hospitalized cases were reported. cases of leptospirosis occurred mostly during the rainy season from de ...201424434593
identification and characterization of a putative chemotaxis protein, chey, from the oral pathogen campylobacter rectus.campylobacter rectus is an understudied oral bacterium that contributes to periodontitis. processes that contribute to the disease-causing capabilities of pathogens, such as chemotaxis, are largely unknown in c. rectus. the aim of this study was to better understand c. rectus chemotaxis, by examining the c. rectus genome for the presence of a chey gene. chey proteins play a part in chemotaxis by acting as two-component response regulators. significantly, chey proteins from several pathogens, inc ...201425598863
infections by leptospira interrogans, seoul virus, and bartonella spp. among norway rats (rattus norvegicus) from the urban slum environment in brazil.norway rats (rattus norvegicus) are reservoir hosts for zoonotic pathogens that cause significant morbidity and mortality in humans. studies evaluating the prevalence of zoonotic pathogens in tropical norway rat populations are rare, and data on co-infection with multiple pathogens are nonexistent. herein, we describe the prevalence of leptospiral carriage, seoul virus (seov), and bartonella spp. infection independently, in addition to the rates of co-infection among urban, slum-dwelling norway ...201424359425
kinetics of leptospira interrogans infection in hamsters after intradermal and subcutaneous challenge.leptospirosis is a zoonosis caused by highly motile, helically shaped bacteria that penetrate the skin and mucous membranes through lesions or abrasions, and rapidly disseminate throughout the body. although the intraperitoneal route of infection is widely used to experimentally inoculate hamsters, this challenge route does not represent a natural route of infection.201425411782
staphylococcus aureus manganese transport protein c (mntc) is an extracellular matrix- and plasminogen-binding protein.infections caused by staphylococcus aureus--particularly nosocomial infections--represent a great concern. usually, the early stage of pathogenesis consists on asymptomatic nasopharynx colonization, which could result in dissemination to other mucosal niches or invasion of sterile sites, such as blood. this pathogenic route depends on scavenging of nutrients as well as binding to and disrupting extracellular matrix (ecm). manganese transport protein c (mntc), a conserved manganese-binding protei ...201425409527
direct detection and differentiation of pathogenic leptospira species using a multi-gene targeted real time pcr approach.leptospirosis is a growing public and veterinary health concern caused by pathogenic species of leptospira. rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. in this work we describe a novel and simple taqman-based multi-gene targeted real-time pcr approach able to detect and differentiate leptospira interrogans, l. kirschneri, l. borgpetere ...201425398140
maintenance of leptospira species in leptospira vanaporn wuthiekanun agar.the maintenance of leptospira species in liquid or semisolid medium is time-consuming and at risk of contamination due to the needs of routine subculture and dark field microscopy. using leptospira vanaporn wuthiekanun (lvw) agar, we maintained 100 pathogenic leptospira isolates for 12 months without the need for subculture and confirmed the viability of all isolates by the naked eye.201425253789
using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the iberian wolf and leptospires.the iberian wolf (canis lupus) is the top predator in the iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. therefore, the wolf can serve as sentinel of environmental contamination with pathogens. we investigated the exposure of free-living wolves to 14 serovars of leptospira interrogans sensu lato. kidney samples from 49 wolves collected from 2010-2013 in northwestern spain were analysed by culture, direct immunofluores ...201425494467
leptospira mayottensis sp. nov., a pathogenic species of the genus leptospira isolated from humans.a group of strains representing species of the genus leptospira, isolated from patients with leptospirosis in mayotte (indian ocean), were previously found to be considerably divergent from other known species of the genus leptospira. this was inferred from sequence analysis of rrs (16s rrna) and other genetic loci and suggests that they belong to a novel species. two strains from each serogroup currently identified within this novel species were studied. spirochaete, aerobic, motile, helix-shap ...201425249563
identification of immunodominant antigens in canine leptospirosis by multi-antigen print immunoassay (mapia).the microscopic agglutination test (mat), the standard method for serological diagnosis of leptospirosis, may present limitations regarding its sensitivity. current studies suggest that leptospira immunoglobulin-like (lig) proteins and lipl32 are of particular interest as serodiagnostic markers since they are present only in pathogenic species of the leptospira genus. the purpose of this study was to identify leptospiral immunodominant proteins that are recognized by canine sera from diseased do ...201425466383
live imaging of bioluminescent leptospira interrogans in mice reveals renal colonization as a stealth escape from the blood defenses and antibiotics.leptospira (l.) interrogans are bacteria responsible for a worldwide reemerging zoonosis. some animals asymptomatically carry l. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. humans are infected through skin contact with leptospires and develop mild to severe leptospirosis. previous attempts to construct fluorescent or bioluminescent leptospires, which would permit in vivo visualization and investigation of host defense mechanisms during in ...201425474719
how water molecules affect the catalytic activity of hydrolases--a xanes study of the local structures of peptide deformylase.peptide deformylase (pdf) is a prokaryotic enzyme that catalyzes the deformylation of nascent peptides generated during protein synthesis and water molecules play a key role in these hydrolases. using x-ray absorption near edge spectroscopy (xanes) and ab initio calculations we accurately probe the local atomic environment of the metal ion binding in the active site of pdf at different ph values and with different metal ions. this new approach is an effective way to monitor existing correlations ...201425503313
detection of zoonotic pathogens and characterization of novel viruses carried by commensal rattus norvegicus in new york city.norway rats (rattus norvegicus) are globally distributed and concentrate in urban environments, where they live and feed in closer proximity to human populations than most other mammals. despite the potential role of rats as reservoirs of zoonotic diseases, the microbial diversity present in urban rat populations remains unexplored. in this study, we used targeted molecular assays to detect known bacterial, viral, and protozoan human pathogens and unbiased high-throughput sequencing to identify ...201425316698
cross-protection between experimental anti-leptospirosis bacterins.we investigated the existence of cross-protection between two anti-leptospirosis monovalent experimental bacterins produced with two strains of leptospira serogroup pomona: fromm strain of serovar kennewicky, isolated from pigs in the united states, and strain gr6 of serovar pomona isolated from pigs in brazil. both were added of aluminum hydroxide as an adjuvant. experimental bacterins were tested with the hamster potency test in order to assess protection provided against the disease and again ...201425477946
leptospirosis from water sources.leptospirosis outbreaks have been associated with many common water events including water consumption, water sports, environmental disasters, and occupational exposure. the ability of leptospires to survive in moist environments makes them a high-risk agent for infection following contact with any contaminated water source. water treatment processes reduce the likelihood of leptospirosis or other microbial agents causing infection provided that they do not malfunction and the distribution netwo ...201425348115
distribution of leptospira serogroups in cattle herds and dogs in france.a retrospective study was conducted to identify and describe the distribution pattern of leptospira serogroups in domestic animals in france. the population consisted of cattle herds and dogs with clinically suspected leptospirosis that were tested at the "laboratoire des leptospires" between 2008 and 2011. the laboratory database was queried for records of cattle and dogs in which seroreactivity in leptospira microagglutination tests was consistent with a recent or current infection, excluding ...201425092816
l,l-diaminopimelate aminotransferase (dapl): a putative target for the development of narrow-spectrum antibacterial compounds.despite the urgent need for sustained development of novel antibacterial compounds to combat the drastic rise in antibiotic resistant and emerging bacterial infections, only a few clinically relevant antibacterial drugs have been recently developed. one of the bottlenecks impeding the development of novel antibacterial compounds is the identification of new enzymatic targets. the nutritionally essential amino acid anabolic pathways, for example lysine biosynthesis, provide an opportunity to expl ...201425309529
structure of homoserine o-acetyltransferase from staphylococcus aureus: the first gram-positive ortholog structure.homoserine o-acetyltransferase (hta) catalyzes the formation of l-o-acetyl-homoserine from l-homoserine through the transfer of an acetyl group from acetyl-coa. this is the first committed step required for the biosynthesis of methionine in many fungi, gram-positive bacteria and some gram-negative bacteria. the structure of hta from staphylococcus aureus (sahta) has been determined to a resolution of 2.45 å. the structure belongs to the α/β-hydrolase superfamily, consisting of two distinct domai ...201425286936
how to find rna thermometers.temperature is one of the decisive signals that a mammalian pathogen has entered its warm-blooded host. among the many ways to register temperature changes, bacteria often use temperature-modulated structures in the untranslated region of mrnas. in this article, we describe how such rna thermometers (rnats) have been discovered one by one upstream of heat shock and virulence genes in the past, and how next-generation sequencing approaches are able to reveal novel temperature-responsive rna struc ...201425279353
severe leptospira interrogans serovar icterohaemorrhagiae infection with hepato-renal-pulmonary involvement treated with corticosteroids.the traditional concept of immediate antibiotic treatment in suspected leptospirosis seems to be especially important for patients up to day 4 of clinical illness. as immune mechanisms probably play a crucial role in advanced leptospirosis with presumed pulmonary hemorrhages, patients might benefit from corticosteroids or other immunosuppressive agents beside antibiotics.201425614810
sage: string-overlap assembly of genomes.de novo genome assembly of next-generation sequencing data is one of the most important current problems in bioinformatics, essential in many biological applications. in spite of significant amount of work in this area, better solutions are still very much needed.201425225118
apoptosis in hep-2 cells infected with ureaplasma diversum.bacterial pathogens have many strategies for infecting and persisting in host cells. adhesion, invasion and intracellular life are important features in the biology of mollicutes. the intracellular location of ureaplasma diversum may trigger disturbances in the host cell. this includes activation or inhibition of pro and anti-apoptotic factors, which facilitate the development of host damage. the aim of the present study was to associate u. diversum infection in hep-2 cells and apoptosis inducti ...201425299837
molecular detection of leptospira spp. in the urine of cattle in northern iran.leptospirosis is a zoonosis of worldwide distribution, caused by leptospira interrogans and is considered as an emerging global public health problem. transmission usually results from direct or indirect exposure to the urine or other body fluids of leptospiruric animals which may become a source of infection for human or other animals. having a humid climate with plenty of annual rainfall, guilan province is a suitable environment for maintaining leptospira spp. hence, early detection of leptos ...201427175139
mammalian gut immunity.the mammalian intestinal tract is the largest immune organ in the body and comprises cells from non-hemopoietic (epithelia, paneth cells, goblet cells) and hemopoietic (macrophages, dendritic cells, t-cells) origin, and is also a dwelling for trillions of microbes collectively known as the microbiota. the homeostasis of this large microbial biomass is prerequisite to maintain host health by maximizing beneficial symbiotic relationships and minimizing the risks of living in such close proximity. ...201425163502
rat sightings in new york city are associated with neighborhood sociodemographics, housing characteristics, and proximity to open public space.rats are ubiquitous in urban environments and, as established reservoirs for infectious pathogens, present a control priority for public health agencies. new york city (nyc) harbors one of the largest rat populations in the united states, but surprising little study has been undertaken to define rat ecology across varied features of this urban landscape. more importantly, factors that may contribute to increased encounters between rats and humans have rarely been explored. using city-wide record ...201425237595
isolation and characterization of two novel plasmids from pathogenic leptospira interrogans serogroup canicola serovar canicola strain gui44.previous genomic analysis of pathogenic leptospira has identified two circular chromosomes but no plasmid. this study aims to investigate potential extrachromosomal elements of l.interrogans serovar canicola strain gui44.201425144555
human leptospirosis trends: northeast thailand, 2001-2012.the objective of this study was to determine the changing trend of leptospirosis over time in thailand using two prospective hospital-based studies conducted amongst adult patients with acute undifferentiated fever (aufi) admitted to maharat nakhon ratchasima hospital, nakhon ratchasima province, thailand between july 2001 to december 2002 and between july 2011 to december 2012. during the first period, leptospirosis (98 patients, 40%) and scrub typhus (59 patients, 24.1%) were the two major cau ...201425141000
role of toll-like receptors in helicobacter pylori infection and immunity.the gram-negative bacterium helicobacter pylori (h. pylori) infects the stomachs of approximately half of the world's population. although infection induces an immune response that contributes to chronic gastric inflammation, the response is not sufficient to eliminate the bacterium. h. pylori infection causes peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma. disease outcome is linked to the severity of the host inflammatory response. gastric epithelial cells represen ...201425133016
murine lung injury caused by leptospira interrogans glycolipoprotein, a specific na/k-atpase inhibitor.leptospiral glycolipoprotein (glp) is a potent and specific na/k-atpase inhibitor. severe pulmonary form of leptospirosis is characterized by edema, inflammation and intra-alveolar hemorrhage having a dismal prognosis. resolution of edema and inflammation determines the outcome of lung injury. na/k-atpase activity is responsible for edema clearance. this enzyme works as a cell receptor that triggers activation of mitogen-activated protein kinase (mapk) intracellular signaling pathway. therefore, ...201425265888
toll-like receptors in the pathogenesis of human b cell malignancies.toll-like receptors (tlrs) are important players in b-cell activation, maturation and memory and may be involved in the pathogenesis of b-cell lymphomas. accumulating studies show differential expression in this heterogeneous group of cancers. stimulation with tlr specific ligands, or agonists of their ligands, leads to aberrant responses in the malignant b-cells. according to current data, tlrs can be implicated in malignant transformation, tumor progression and immune evasion processes. most o ...201425112836
molecular detection of leptospiral dna in environmental water on st. kitts.leptospirosis is an important waterborne zoonotic disease caused by pathogenic leptospira. the pathogen is maintained in a population due to chronic colonization and shedding from renal tubules of domestic and wild animals. humans and other animals become infected when they come in contact with urine from infected animals, either directly or through urine-contaminated surface water. in this study, we screened environmental water on the island of st. kitts by using a taqman based real time quanti ...201425105546
sensitivity of real-time pcr performed on dried sera spotted on filter paper for diagnosis of leptospirosis.in remote countries, leptospirosis confirmation is difficult because it requires the shipment of frozen samples to reference laboratories. the sensitivity of leptospirosis real-time pcr performed on filter paper-dried serum samples stored at ambient temperature was evaluated at 2 × 10(2) equivalent leptospires/ml (eqleptospires/ml). this easy alternative procedure can be used to enhance the surveillance of leptospirosis.201424899024
recognition of lps by tlr4: potential for anti-inflammatory therapies.lps molecules of marine bacteria show structures distinct from terrestrial bacteria, due to the different environment that marine bacteria live in. because of these different structures, lipid a molecules from marine bacteria are most often poor stimulators of the toll-like receptor 4 (tlr4) pathway. due to their low stimulatory potential, these lipid a molecules are suggested to be applicable as antagonists of tlr4 signaling in sepsis patients, where this immune response is amplified and unregu ...201425056632
vapc from the leptospiral vapbc toxin-antitoxin module displays ribonuclease activity on the initiator trna.the prokaryotic ubiquitous toxin-antitoxin (ta) operons encode a stable toxin and an unstable antitoxin. the most accepted hypothesis of the physiological function of the ta system is the reversible cessation of cellular growth under stress conditions. the major ta family, vapbc is present in the spirochaete leptospira interrogans. vapbc modules are classified based on the presence of a predicted ribonucleasic pin domain in the vapc toxin. the expression of the leptospiral vapc in e. coli promot ...201425047537
a facile and sensitive method for quantification of cyclic nucleotide monophosphates in mammalian organs: basal levels of eight cnmps and identification of 2',3'-cimp.a sensitive, versatile and economical method to extract and quantify cyclic nucleotide monophosphates (cnmps) using lc-ms/ms, including both 3',5'-cnmps and 2',3'-cnmps, in mammalian tissues and cellular systems has been developed. problems, such as matrix effects from complex biological samples, are addressed and have been optimized. this protocol allows for comparison of multiple cnmps in the same system and was used to examine the relationship between tissue levels of cnmps in a panel of rat ...201425513747
update on refseq microbial genomes resources.ncbi refseq genome collection http://www.ncbi.nlm.nih.gov/genome represents all three major domains of life: eukarya, bacteria and archaea as well as viruses. prokaryotic genome sequences are the most rapidly growing part of the collection. during the year of 2014 more than 10,000 microbial genome assemblies have been publicly released bringing the total number of prokaryotic genomes close to 30,000. we continue to improve the quality and usability of the microbial genome resources by providing ...201425510495
update on refseq microbial genomes resources.ncbi refseq genome collection http://www.ncbi.nlm.nih.gov/genome represents all three major domains of life: eukarya, bacteria and archaea as well as viruses. prokaryotic genome sequences are the most rapidly growing part of the collection. during the year of 2014 more than 10,000 microbial genome assemblies have been publicly released bringing the total number of prokaryotic genomes close to 30,000. we continue to improve the quality and usability of the microbial genome resources by providing ...201425510495
dimeric structure of the bacterial extracellular foldase prsa.secretion of proteins into the membrane-cell wall space is essential for cell wall biosynthesis and pathogenicity in gram-positive bacteria. folding and maturation of many secreted proteins depend on a single extracellular foldase, the prsa protein. prsa is a 30-kda protein, lipid anchored to the outer leaflet of the cell membrane. the crystal structure of bacillus subtilis prsa reveals a central catalytic parvulin-type prolyl isomerase domain, which is inserted into a larger composite nc domain ...201425525259
dimeric structure of the bacterial extracellular foldase prsa.secretion of proteins into the membrane-cell wall space is essential for cell wall biosynthesis and pathogenicity in gram-positive bacteria. folding and maturation of many secreted proteins depend on a single extracellular foldase, the prsa protein. prsa is a 30-kda protein, lipid anchored to the outer leaflet of the cell membrane. the crystal structure of bacillus subtilis prsa reveals a central catalytic parvulin-type prolyl isomerase domain, which is inserted into a larger composite nc domain ...201425525259
rapid and sensitive detection of bartonella bacilliformis in experimentally infected sand flies by loop-mediated isothermal amplification (lamp) of the pap31 gene.carrion' disease, caused by bartonella bacilliformis, remains truly neglected due to its focal geographical nature. a wide spectrum of clinical manifestations, including asymptomatic bacteremia, and lack of a sensitive diagnostic test can potentially lead to a spread of the disease into non-endemic regions where competent sand fly vectors may be present. a reliable test capable of detecting b. bacilliformis is urgently needed. our objective is to develop a loop-mediated isothermal amplification ...201425522230
recombinant antigens rlipl21, rloa22, rlipl32 and rligacon4-8 for serological diagnosis of leptospirosis by enzyme-linked immunosorbent assays in dogs.animal leptospirosis is one of the most common zoonotic diseases in the united states and around the world. in a previous study, we applied four recombinant antigens, rlipl21, rloa22, rlipl32 and rligacon4-8 of leptospira interrogans (l. interrogans) for the serological diagnosis of equine leptospirosis (ye et al, serodiagnosis of equine leptospirosis by elisa using four recombinant protein markers, clin. vaccine. immunol. 21:478-483). in this study, the same four recombinant antigens were evalu ...201425526513
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